This Application claims the benefit of the Japanese Patent No. 10-109785, filed Apr. 20, 1998, the entire contents of which are hereby incorporated herein by reference.
The present invention relates to a vector quantization method used to quantize a linear predictive coefficient in speech encoding and, more particular, to a vector quantization method having constraints in quantization vectors.
A technique for performing linear prediction analysis of speech, decomposing the analysis result into a residual signal and a linear predictive coefficient representing a spectrum envelope, and processing them has been popular. A CELP (Code Exited Linear Prediction) scheme extensively studied recently in the fields of speech encoding is also based on the linear prediction analysis. A linear predictive coefficient and residual signal are quantized by VQ (Vector Quantization). In the CELP scheme, the linear predictive coefficient is often transformed into an LSP (Line Spectrum Pair) parameter, and then quantized. According to one of the reasons for this, stability of a synthesis filter can be easily discriminated.
In the CELP scheme, the synthesis filter is arranged on the basis of the LSP parameter on the decoding side. The quantized residual signal is passed through the synthesis filter to generate decoded speech. For this reason, unless the synthesis filter is stable, the decoded speech oscillates to greatly degrade the speech quality.
As is well known, if an LSP parameter w={w1, w2, . . . , wp} obtained by linear prediction analysis of degree p satisfies the following condition:
o less than w1 less than w2 less than . . .  less than wp less than xcfx80xe2x80x83xe2x80x83(1)
the synthesis filter is stable. The order of magnitudes of components of the LSP parameter represented by condition (1) (to be referred to as an LSP parameter order hereinafter) is checked to allow easily determining the stability of the synthesis filter.
When an interval between the parameter components w1, w2, . . . , wp decreases although the LSP parameter order is not reversed, the synthesis filter abruptly becomes unstable. Care must be taken for quantizing the LSP parameter components having small intervals. Small quantization errors generated by the LSP parameter components having small intervals greatly influence stability of the synthesis filter.
To solve the above problem, conventionally, a predetermined value D is defined for an interval between the adjacent LSP parameter components. When the interval between the adjacent components of the quantized LSP parameter is smaller than the predetermined value D, an appropriate countermeasure is made. Japanese Patent No. 2,659,605 (reference 1) describes a method of performing correction processing to increase a small interval between the adjacent components to assure the predetermined value D. This method is simple and easy, but distortion by correction processing is not evaluated in quantization.
Jpn. Pat. Appln. KOKAI Publication No. 6-120841 (reference 2) discloses a technique for solving the above problem. In reference 2, stability check and, as needed, correction processing are performed for each quantized LSP parameter obtained from a codebook. The distance between the corrected quantized LSP parameter and the input LSP parameter is calculated. With this technique, the distortion generated by correction processing can be included in quantization distortion and then evaluated, thereby improving quantization efficiency. According to this method, however, the calculation quantity increases because stability check must be performed for all quantized LSP parameters within the search loop of the codebook.
As described above, if a constraint such as the LSP parameter order or the interval between adjacent components is imposed on the quantization vector, it must be checked if the quantization vector satisfies the constraint after quantization or within the search loop of the codebook in order to assure stability of the synthesis filter. This check must desirably be performed in a smaller quantity of calculation. In particular, the calculation quantity increases with an increase in the number of candidates of the codebook in the check within the search loop. A small difference in calculation quantity becomes a large difference as a whole. A reduction in calculation quantity in the check is an important problem. According to the conventional methods, however, it is difficult to check if the quantization vector satisfies the constraint in a small calculation quantity, as described above.
In quantizing an LSP parameter upon nonlinear transform such as logarithmic transform, it is difficult to calculate the interval between the adjacent components in the transform range.
It is an object of the present invention to provide a vector quantization apparatus capable of efficiently obtaining a quantization vector satisfying a constraint in a smaller calculation quantity and a vector quantization method therefor.
According to the present invention ,there is provided a vector quantization apparatus comprising a codebook which stores a plurality of code vectors; a constraint relieving section which relieves a predetermined constraint imposed on a quantization vector from an input vector input to an input terminal to generate a target vector, a error calculating section which calculates an error between the target vector and a code vector extracted from the codebook, and an error evaluation section for evaluating this error, selecting from the codebook a code vector constituting an unconstrained quantized vector for approximating the target vector, and outputting an index representing the code vector.
According to the invention, there is provided a vector quantization method comprising quantizing an input vector upon appropriately transforming the input vector on an encoding side in advance, and transforming a decoding result in an inverse manner to the transform of the input vector to obtain a quantization vector satisfying a constraint, thereby reducing the calculation quantity as compared to the conventional case.
More specifically, on the encoding side, an input vector is transformed with a predetermined transform function to generate a target vector. At least one code vector constituting a first quantization vector that approximates this target vector is selected from a codebook, and an index representing the selected code vector is output. The transform function transforms the first quantization vector in an inverse manner to the transform of the input vector to generate a second quantization vector satisfying a predetermined constraint.
The decoding side receives the index representing at least one code vector constituting the first quantization vector that approximates the target vector generated by transforming the input vector with the predetermined transform function. This code vector is extracted from a codebook. The first quantization vector constituting the code vector is transformed in an inverse manner to the transform function to generate the second quantization vector. Note that the transform function is designed to allow the second quantization vector to satisfy the predetermined constraint.
The vector quantization method according to the present invention is particularly suitable for LSP parameter vector quantization. In quantizing an LSP parameter vector, an LSP parameter serves as an input vector on the encoding side. A constraint vector representing a predetermined constraint is subtracted from the input vector to generate a target vector. At least one code vector constituting a first quantization vector having a minimum error with respect to the target vector is selected from a codebook. An index representing the selected code vector is output. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting a second quantization vector generated by synthesizing the first quantization vector and the constraint vector has a predetermined value or more.
The decoding side receives the index representing at least one code vector constituting the first quantization vector having the minimum error with respect to the target vector obtained upon subtracting the constraint vector representing the predetermined constraint from the input vector made of the LSP parameter. This code vector is extracted from a codebook. The constraint vector is added to the first quantization vector made of this code vector to generate the second quantization vector. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting the second quantization vector is the predetermined value or more.
The vector quantization method according to the present invention is also applicable to LPC parameter predictive coding. In this case, on the encoding side, an LSP parameter serves as an input vector. A constraint vector representing a predetermined constraint is subtracted from the input vector to generate a target vector. At the same time, a predictive vector is generated using a vector obtained by subtracting the constraint vector from a previous quantization vector. At least one code vector synthesized with this predictive vector and constituting a first quantization vector having a minimum error with respect to the target vector is selected from a codebook. An index representing this code vector is output. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting the second quantization vector generated by putting together the first quantization vector and the constraint vector is a predetermined value or more in the same manner as described above.
The decoding side receives the index representing at least one code vector constituting the first quantization vector having the minimum error with respect to the target vector generated by subtracting the constraint vector representing the predetermined constraint from the input vector made of the LSP parameter. This code vector is extracted from a codebook, and at the same time, the predictive vector is generated using the vector obtained by subtracting the constraint vector from the past quantized vector. The first quantization vector is generated by synthesizing this code vector and the predictive vector. The first quantization vector and the constraint vector are synthesized to generate the second quantization vector. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting the second quantization vector has the predetermined value or more in the same manner as described above.
According to still another vector quantization method of the present invention, an LSP parameter serves as an input vector on the encoding side. A constraint vector representing a predetermined constraint is subtracted from this input vector. The difference is nonlinearly transformed to generate a target vector. The constraint vector is subtracted from a past quantized vector. The difference is nonlinearly transformed to generate a predictive vector. At least one code vector synthesized with this predictive vector and constituting a first quantization vector having a minimum error with respect to the target vector is selected from a codebook. An index representing this code vector is output. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting the second quantization vector generated by putting together the first quantization vector and the constraint vector is a predetermined value or more in the same manner as described above.
The decoding side receives the index representing at least one code vector constituting the first quantization vector having the minimum error with respect to the target vector generated by subtracting the constraint vector representing the predetermined constraint from the input vector made of the LSP parameter and nonlinearly transforming the difference. This code vector is extracted from a codebook, and at the same time, the predictive vector is generated using the vector obtained by subtracting the constraint vector from the past quantized vector and nonlinearly transforming the difference. The first quantization vector is generated by putting together this code vector and the predictive vector and then subjected to a nonlinear inverse transformation, and then the first quantization vector and the constraint vector are synthesized to generate the second quantization vector. Note that the constraint vector is designed such that the interval between the adjacent components of the quantized LSP parameter constituting the second quantization vector has the predetermined value or more in the same manner as described above.
As described above, according to the present invention, the input vector is transformed to relieve the predetermined constraint from the quantization vector in encoding. In decoding the quantization vector, the quantization vector is decoded and then transformed in an inverse manner to the transform in encoding the input vector to generate the quantization vector satisfying the constraint. Whether the quantization vector satisfies the constraint can be checked in a small calculation quantity.
More specifically, when LSP parameter vector quantization is taken into consideration, the constraint for keeping the interval between the adjacent components of the LSP parameter to the predetermined value must be imposed on the quantization LSP vector in addition to the condition of the LSP parameter order in order to assure stability of the synthesis filter. The calculation quantity necessary for checking if the latter condition is satisfied becomes an important problem. According to the present invention, this check can be performed by comparing the magnitudes of the adjacent components, thereby greatly reducing the calculation quantity.
In quantizing the LSP parameter upon its nonlinear transform such as logarithmic transform, the constraint is subtracted before the transform, thereby eliminating the calculation for the interval of the transformed LSP parameter in quantization.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.


The demand for systems that use a variety of devices at a location to monitor a variety of conditions, such as monitoring homes and businesses for alarm conditions, allowing users to centrally control various devices (such as thermostats, switches, cameras, appliances, etc.), monitor medical conditions, and the like has continued to grow as more home and business owners seek better control over their premises and to protect it from various hazards and threats. Such hazards and threats include intrusion, fire, carbon monoxide and flooding, among others dangers that may be monitored and reported to a monitoring station.
Conventional systems typically employ a control panel and/or gateway that receive “event” (such as triggering alarms) and other information from various sensors and devices, and is used to operate them. This may be done locally by the user, or remotely via a monitoring center. In the case of alarm events, the monitoring center can also take appropriate action, such as notifying emergency responders. Installation and servicing complexity associated with these systems tends to be high, as an installer has to physically position, mount, and configure the control panel and all of the various sensors, while taking into account a variety of performance characteristics and requirements for each device to ensure proper operation of the system. These systems also typically incorporate a manufacturer's specific technology designed for the manufacturer's security application, and only certain devices may only appropriately interoperate with other devices in certain ways. This is true as well for more recent all-in-one (AIO) security systems, in which the control panel and a user interface (such as a keypad) are combined in a single unit, even portable AIO systems where the control panel may be relocated around the premises and not permanently installed. For example, such units may sit on top of a table or on the floor, but nevertheless communicates with life safety sensors in a similar manner as a wall-mounted security panel.
However, these existing security systems suffer from the same problem, namely, a lack of health monitoring of the security system. In particular, these existing security systems only generate a system alert when the health levels of sensors or components fall below predefined minimum thresholds. For example, a battery alert for a sensor will only trigger an alert when the battery is falls below an operational threshold, but this operational threshold typically corresponds to a battery level of where the sensor or component is forced to turn off or will turn off shortly. In other words, health level thresholds in existing systems are only triggered when the levels are so bad such that at least one sensor or component of the system stops functioning properly.
Further, customers have no way of knowing when the heath levels of their security systems are going to degrade to the point that functionality, i.e., monitoring capabilities, of the security system are affected. Such a failure may come at an inopportune time such as when the customer is on vacation or otherwise away from the premise. Therefore, the user is not able to fix the problem, e.g., change batteries, or call for a service technician because the customer may not even know a problem exist until the customer returns to the premise. Such a sudden failure in monitoring capabilities of these existing security systems may inadvertently provide thieves the window of opportunity they have been waiting for.


Field
The present disclosure relates to an extension device for a bone anchor, in particular for use in minimally invasive surgery (MIS). The present disclosure also relates to a system including such an extension device and a bone anchor, where the bone anchor includes an anchoring section and a receiving part for receiving a rod to couple the rod to the anchoring section. The extension device includes a first sleeve and a second sleeve positioned within the first sleeve. The extension device also includes a coupling structure that allows the extension device to couple to the receiving part of the bone anchor and that inhibits translational and rotational movement of the extension device relative to the receiving part.
Description of Related Art
Extension devices, also called head extenders, for pedicle screws for use in minimally invasive surgery are known in the art. For example, U.S. Pat. No. 7,563,264 B2 describes a spinal stabilization system for a minimally invasive procedure wherein detachable sleeves may be coupled to a collar of a bone anchor to allow for formation of the spinal stabilization system through a small skin incision. The detachable sleeve members may allow for alignment of the collars to facilitate insertion of an elongated member in the collars. A coupling system is provided between the sleeve and the collar that inhibits translational movement of the sleeve relative to the collar. In one embodiment, the sleeve may be coupled to a collar of a bone fastener assembly with movable members that may be threaded into threaded openings in the collar.
WO 2013/112689 A2 describes a minimally invasive tower access device comprising an elongated outer sleeve that slidably receives an elongated inner sleeve. A lock nut is used to secure the inner sleeve and outer sleeve in a locked mode.


A considerable need exists for a dosage form useful for treating cardiovascular diseases. The dosage form should be therapeutically indicated for treating cardiovascular diseases including angina pectoris, hypertension, congestive heart failure, and possess vasodilation properties for decreasing systemic vascular resistance.
The beneficial drug isradipine is therapeutically indicated for treating cardiovascular diseases. The cardiovascular diseases include angina pectoris, hypertension and congestive heart failure as disclosed in a patient study reported in The American Journal of Cardiology, Vol. 59, pp 70B-74B, (1987). The drug was administered in the study in a bulk, nonrate uncontrolled dose that was subjected to the changing adverse environment of the gastrointestinal tract.
In light of the above presentation it will be appreciated by those versed in the dispensing art to which this invention pertains that a pressing need exists for a rate controlled dosage form that can deliver the valuable drug isradipine to a patient in critical need of cardiovascular therapy. The pressing need exists also for an oral dosage form that can deliver isradipine at a controlled rate in a constant dose per unit time over a prolonged period of time for its beneficial hemodynamic effects substantially independent of the variable environment of the gastrointestinal tract. It will be appreciated further by those versed in the dispensing art that such a novel and unique dosage form that can administer isradipine in a rate controlled dose over time, and simultaneously provide cardiovascular therapy, would represent an advancement and valuable contribution to the art.


1. Field of the Invention
The present invention relates to a method and an apparatus for detecting combustion pressure in an internal combustion engine. More particularly, the present invention concerns a combustion pressure detecting method and apparatus for an engine whereby errors in detection may be rectified.
2. Description of the Prior Art
There are various known pressure sensors for detecting combustion pressure in an engine such as those of piezo-electric type, semiconductor type, capacitive type and others. However, every one of these known sensors encounters difficulty in detecting the pressure of combustion with a reasonably high accuracy over an extended period (use life) under adverse environmental conditions such as high voltage, high temperature and high pressure. Thus none of these sensors is particularly suited for installation to motor vehicles. In addition to the aforementioned sensors, there may be mentioned a pressure sensor in which optical fibers are used. By way of example, Japanese Unexamined Patent Publication No. 59-60334 discloses a typical one of the hitherto known pressure sensor in which optical fibers are used.
The known pressure sensor employing optical fiber is generally intended for use in process controls. When this sensor is employed as a combustion pressure detecting device in an engine, there arises a problem that temperature of the pressure detecting device itself varies over a very wide range under the influence of combustion temperature in the engine so the device has the disadvantage that it is impossible to accurately measure the combustion pressure.


Along with social progress and technology development, more and more people use access terminals to wirelessly connect to the Internet or enterprise internal networks to acquire information. In order to improve browsing speed and experience of mobile device browsers, pre-reading function has already been achieved by the mobile device browsers, i.e. webpage pre-reading can be carried out by reading a keyword in advance, and after a pre-reading page is completely loaded, a webpage can be switched to enter the pre-reading page, and the contents of the pre-reading page can be displayed.
However, in implementing a webpage pre-reading process on existing mobile device browsers, due to the fact that nearly all the page contents (for example, pictures of products and the like) are loaded in a layzyload mode, JS (JavaScript) cannot load or display all of the contents (for example, part of the product pictures and the like) in the pre-reading webpage. Thus, the user experience is influenced.


High quality printing paper must have a number of physical properties. Two of the most important are a flat and smooth surface to facilitate printing in a press and gloss to produce a more attractive surface, particularly after printing. These properties can be obtained by a variety of techniques, such as coating the paper with pigments and binder and finishing it in one or more pressing operations.
One of the most common finishing operations employed in the manufacture of printing paper is supercalendering, in which paper is passed through a series of nips formed by steel rolls pressed against cotton filled rolls at very high pressures, typically at nip loads between 175 KN/M and 437.5 KN/M (1000 and 2500 pounds per lineal inch). This typically results in nip pressures of 13,780 KN/M.sup.2 to 27,560 KN/M.sup.2 (2000 to 4000 p.s.i.).
Traditional supercalender stacks are not externally heated, but heat is generated when the cotton filled rolls subjected to the extremely high pressures in the nip flex intermittently with each revolution. The nip temperatures in such supercalenders typically reach levels of about 71.degree. C. (160.degree. F.). Another important element in producing good results is having a high moisture content in the paper as it passes through the supercalender. Typically, the moisture content will be 7% to 9%, or higher, of the bone dry fiber weight. Flatness, smoothness and high gloss are obtained in supercalenders because of extreme compression and densification of the sheet. The densification undesirably results in reduced opacity and a blackening effect in overly moist portions.
Supercalenders commonly consist of a large number of rolls (9 to 14), alternating steel and resilient, in order to obtain the desired smoothness and gloss. In order to obtain smoothness on both sides it is necessary to run an even number of rolls and with two resilient rolls (so called "cushion rolls") running together midway in the stack to perform the necessary reversing of the side toward the steel rolls. This action is only partly successful at providing two smooth sides since the first side finished towards the steel is later deformed by the exposure to the resilient rolls.
Because of this shortcoming and the inherent mechanical problem associated with the "cushion roll" nip, many supercalenders operate today with an uneven number of nips and no "cushion roll" nip, which results in only one side being finished against the steel, and while gloss values may be manipulated to be close on the two sides, inevitably one side is noticeably rougher than the other.
Another form of finishing is machine calendering wherein the paper web is passed between two normally unheated steel rolls pressed together at high pressures. This process produces smoothness, but little gloss because of the absence of shear in the nip.
Another common finishing operation is gloss calendering, which uses heated finishing rolls to produce high gloss finishes on coated paper or board without the high pressure of supercalendering. The nip pressures for commercial machines are typically between about 87.5 to 175 KN/M (500 to 1000 pounds per lineal inch) of nip loading. This typically results in nip pressures of 6,890 KN/M.sup.2 to 13,780 KN/M.sup.2 (1000 to 2000 p.s.i.). The lower pressure causes less densification of the paper, and therefore, better opacity, while the higher temperature softens the coating and permits better gloss enchancement. However, the finishing effect is limited to the coating and the uppermost surface of the web. Thus, the surface of the sheet is not as smooth and flat as that produced in supercalendering and has generally been applied to coated board rather than high quality papers. As a result, gloss calendered sheets do not print as satisfactorily in a printing press as do supercalendered sheets.
In recent years, many modifications have been made to gloss calendering, machine calendering and supercalendering operations. Some supercalenders have been heated, primarily to improve the uniformity and control of the temperature. Typically, heated supercalenders reach nip temperatures of about 82.degree. C. (180.degree. F.). Temperatures of some machine calenders or supercalenders have been further increased in an attempt to allow a decrease in pressure to produce the same results. In spite of this modification of supercalendering in the direction of gloss calendering, the fundamental effects of the two processes have remained distinct. Supercalendering uniformly compacts the entire sheet to a high degree, thus flattening the surface fibers and all others, as well as producing gloss on the surface. In contrast, gloss calendering molds, flattens, and glosses the surface of the coating and, in the case of uncoated paper the top surface of the fibrous substrate, but compacts the remainder of the sheet much less than supercalendering.
Examples of gloss calendering are disclosed in U.S. Pat. Nos. 3,124,504; 3,124,480; 3,124,481; 3,190,212; and 3,254,593. These patents collectively describe apparatus capable of nip temperatures from below the boiling point of water to as high as 232.degree. C. (450.degree. F.) and nip pressures from 1,722 to 17,220 KN/M.sup.2 (250 to 2500 p.s.i.). U.S. Pat. No. 3,124,480 describes finishing steps designed to heat the coating on paper to a temperature which temporarily platicizes at least the surface of the coating in contact with the hot drum. A form of supercalendering in which the rolls are heated to relatively high temperatures is disclosed in U.S. Pat. Nos. 3,442,685 and 3,451,331. These patents disclose a method and apparatus capable of producing high gloss on coated paper by heating at least one roll of a supercalender stack to a temperature between 82.degree. C. and 163.degree. C. (180.degree. F. and 325.degree. F.) to plasticize the coating.
The one parameter which has been found to be the most critical in gloss calendering and supercalendering has been the moisture content of the paper. High moisture improves the smoothing and glossing effects of both the coating and the paper substrate. Many developments in supercalendering and gloss calendering involve techniques for increasing the moisture in the web or at least in some portions of it before finishing.
Unfortunately, moisture is an undesirable control parameter. Small variations in moisture cause large variations in the finished properties of the paper. Also, it is undesirable to have more than about 3.5% to about 4.5% moisture in the finished sheet to avoid uneven reel building and sheet curl from later drying. This amount of moisture is a stable amount, and the sheet will not dry significantly below this level under ambient conditions. To have a finished product with the desired low moisture content and still have the desired high moisture content (e.g. 7% to 9%) to facilitate calendering, many heated calendering operations have increased the drum temperature to dry the moister webs.
Nonuniformity of moisture in the sheet can be even a bigger problem than too much moisture. By nonuniformity, it is meant that the moisture content at one place on the sheet is higher or lower than at other locations across the width of the sheet. The nonuniformity can also exist in the machine direction and the thickness of the sheet. Nonuniformity is most severe when calendering takes place immediately after coating, which is to say when the calender is in line with the coater. If coating is done in a separate operation from calendering, the moisture content of the coated paper has time to equalize thoughout the web before calendering.
The above cited U.S. Pat. No. 3,124,504 is primarily concerned with very moist webs (up to 35% or 50% moisture) and includes the concept of drying the web while finishing it. Very high temperatures are employed for drying, but temperatures above the boiling point of water are said to be needed only if the web is wetter than 5% to 8% of the bone dry weight. The web moisture content is also noted as being an important element in the process disclosed in above cited U.S. Pat. Nos. 3,442,685 and 3,451,331. The patents teach that it is best for the paper to have about 7% moisture content, and moisture can be added before the supercalender to improve the finishing effects. The addition of moisture before finishing is also described in above cited U.S. Pat. No. 3,124,481 to manufacture glazed uncoated paper. U.S. Pat. No. 2,214,641 also moistens the surface of the web before finishing. In U.S. Pat. No. 4,012,543, gloss calendering is undertaken immediately after coating before too much of the moisture is lost from the coating. In this disclosure, finishing is carried out at a web moisture content of 9% to 10% of the bone dry weight. In contrast, U.S. Pat. No. 3,268,354, takes special steps to dry the surface of the coating, but to maintain a wet interface between the coating and the fibrous web before gloss calendering. The web in this disclosure has a moisture content of at least 15% at the interface.


FIG. 12 shows a perspective view schematically illustrating an embodiment of a card-type device (refer to Patent Document 1, for example). A card-type device 40 has a wireless communication function, and includes a circuit board 41, a flat housing 42 which accommodates the circuit board 41, and an antenna structure body 43 which is disposed outside of the housing 42 and which performs wireless communication utilizing radio waves. The antenna structure body 43 includes an antenna turning shaft 44 at a base end thereof, and the antenna turning shaft 44 projects from the antenna structure body 43. The housing 42 has a through-hole on one side which allows the antenna turning shaft 44 to be inserted into the housing 42. The housing 42 also has inside thereof a bearing (not shown) which receives the antenna turning shaft 44. With this configuration of the card-type device 40, the antenna structure body 43 turns on the antenna turning shaft 44, and the shaft 44 acts as the axis of turn. For example, when the card-type device 40 is used by being inserted into a card slot of an information terminal apparatus such as a personal computer, the antenna structure body 43 is turned so as to stand on an upper surface of the housing 42 as shown by a dashed line in FIG. 12. Thereby, the sensitivity to radio waves for transmission/reception is enhanced. On the other hand, when the card-type device 40 is detached from the card slot of the information terminal apparatus and is carried about, the antenna structure body 43 is turned into an accommodated flat position to be laid flat as shown by a solid line in FIG. 12. Thus, the card-type device 40 is readily carried.    Patent Document 1: Japanese Unexamined Patent Application Publication No. 2001-69029    Patent Document 2: Japanese Unexamined Patent Application Publication No. 2001-243435    Patent Document 3: Japanese Unexamined Patent Application Publication No. 6-21846
In the configuration of the card-type device 40 shown in FIG. 12, in order to turn the antenna structure body 43 from the flat position to the upright position, the antenna structure body 43 is turned upward manually, for example, drawn up using a nail. The manual operation of turning the antenna structure body 43 upright is troublesome, and therefore, the device 40 is not user-friendly.


1. Field
A method for function monitoring in medical accelerator systems is provided.
2. Related Art
Accelerator systems that generate high-energy electromagnetic radiation or particle radiation are used in medicine for radiation therapy. Radiation therapy exposes regions of a patient's body to the radiation. Energy is transmitted to these exposed regions in order to bring about changes in cell components. Radiation therapy is used particularly in treating cancer by killing tumor cells or reducing the capability of the cells to divide. Both linear and cyclic accelerators can be used in accelerator systems.
Conventionally, it has been necessary to manually connect an oscilloscope to a box in the control room of the accelerator system. This connection enables a user to monitor the signals from the accelerator system relevant for the operation. A proper connection requires time-consuming tuning of the oscilloscope. In addition, the signal information obtained by the oscilloscope must be separately recorded, for example, on paper.
Since the information obtained must be recorded separately, only a small portion of the signal data, for example the amplitude and width, can be picked up or acquired. Generally, this data acquisition is done only at relatively long maintenance intervals, for example, every three months.
Even with arrangements for transmitting the signals received to a servicing device by modem, intervention by the user is still required. The user must still connect the oscilloscope and forward the data. Data acquisition is limited to the brief times in which an oscilloscope is connected. Because of the difficulty of connecting the oscilloscope and tuning the signal, data acquisition generally only takes place when the accelerator system malfunctions or during routine maintenance at certain relatively long maintenance intervals. Thus, monitoring the accelerator system during the operation of the system is hardly possible because the presence of a system technician in the operation room could bother the medical personnel who are operating the system.
Thus, a method that permits improved function monitoring in medical accelerator systems is desired.


Conventional plug and play technology can be a contradiction in terms. In more detail, plug and play technology can enable creation of interfaces and establishment of communications between multiple devices. Ideally, the creation of the interfaces and subsequent communications occur with a minimal amount of user activity. However, for conventional plug and play technology, this may not always be the case.
For example, devices can include or be associated with different components, operating systems, protocols, etc. Thus, a user attempting to interface a personal organizer with a personal computer, for example, may not be able to initiate user interface creation and enable communications between the devices by physically connecting the devices. When interfacing the personal organizer with the personal computer for the first time, the communications protocols and associated software considerations must first be analyzed and configured on both machines before any useful communication between the devices can occur.
One drawback of conventional plug and play technology is that software is required for both devices. The software usually accompanies a device in packaging in which the device was purchased (e.g., encapsulated within a compact disk). Inclusion of the software together with the product is associated with various inefficiencies. For instance, it can be costly to create software and package it together with a device. For example, in order to place software together with a device within device packaging, costs associated with making, testing, developing, fixing bugs, customizing, branding, burning, etc. are incurred. Additionally, presenting the software on a storage media is associated with other problems. In order to establish compatibility between two devices, a compact disk or other media that includes the software must be present. This can be inconvenient for a traveler who is attempting to interface two devices for a first time, but did not remember to bring the compact disk that retains the requisite software. Inclusion of software is also inefficient because of increased effort required by the user.
To complicate matters, compatibility issues may exist between a device that is desirably interfaced and the compatibility software. For example, the compatibility software can be stored on a CD or DVD drive, whereas a personal computer to which a personal digital assistant is desirably interfaced may not be associated with either drive. Additionally, the personal computer upon which the traveler wishes to install compatibility software may have administrative passwords or some other security functionality that prevents the traveler from using the device. To further complicate matters, it is possible that the traveler lacks the technical knowledge to overcome problems associated with installing compatibility software on a personal computer.
The Internet is also a popular medium from which to obtain software that facilitates plug-and-play functionality between devices. The Internet solves some problems associated with conventional plug and play technology, such as not forcing an individual to retain physical possession of the storage media that houses the device compatibility software. Using the Internet, however, as a storage media for compatibility software is not without its faults. One such fault is that at least one of the desirably synchronized devices (e.g., a personal computer) requires an Internet connection in order to obtain the compatibility software. Furthermore, the user may be required to find the appropriate web site in order to locate the compatibility software. Again, the technically deficient user may encounter difficulties in finding the required software in the vastness of the Internet


1. Field of the Invention
The present invention relates to isocyanurate-modified polyisocyanate compositions, to a process for the preparation thereof, and to microcellular foams prepared from said polyisocyanate compositions. More particularly, the invention relates to polyisocyanate compositions containing isocyanurate linkages prepared by reacting said polyisocyanate in the presence of an alkali metal organo-hydroxamate or the metal salt-free acid complex, hereinafter referred to as the "half-salt."
2. Description of the Prior Art
The prior art generally teaches the preparation of isocyanurate-modified isocyanate products, employing a variety of catalysts. U.S. Pat. No. 3,996,223 teaches a process for the preparation of polyurethane quasi-prepolymers containing isocyanurate structures by polymerization in the presence of catalytic quantities of a mixture of Mannich bases and carbamic acid esters from isocyanate and alcohols containing secondary alcohol groups. U.S. Pat. No. 3,645,979 teaches the polymerization of an aromatic polyisocyanate and an aliphatic polyisocyanate in the presence of an organic phosphine catalyst. U.S. Pat. No. 3,652,424 teaches a process for the preparation of polyisocyanate compositions containing 5 to 19 percent by weight of toluene diisocyanate trimer by employing as trimerization catalysts substituted guanidines and isobiguanidines.


With increasing development of science and technology, the processing speed of a computing chip for an electronic device is gradually increased. Consequently, a great amount of waste heat is generated while the computing chip is operated. It is a critical issue to dissipate the heat. For example, a computer host comprises a main board and a display card. The display card is mounted on the main board. Generally, the chip of the display card generates more heat than the main board. Consequently, the heat generated by the chip of the display card has to be dissipated in high priority.
However, for most electronic devices, plural function circuit boards are mounted on the main board in parallel and arranged side by side. Since the airflow for convection is usually obstructed by the adjacent function circuit boards, the heat generated by the chip of the display card cannot be efficiently dissipated away by the existing heat-dissipating mechanism. Therefore, the heat-dissipating mechanism of the electronic device needs to be further improved.


1. Technical Field
The present invention relates to a liquid ejection head, such as an ink-jet type recording head, a liquid ejection apparatus, and a manufacturing method of a liquid ejection head, and more particularly to a liquid ejection head which includes a channel unit provided with a series of liquid channels extending from a common liquid chamber down to nozzle orifices through pressure chambers and which can discharge liquid in the form of liquid droplets from the nozzle orifices thereof, a liquid ejection apparatus, and a manufacturing method of a liquid ejection head.
2. Related Art
As for liquid ejection heads structured to discharge out liquid droplets from nozzle orifices thereof by causing pressure fluctuation to liquid accommodated in pressure chambers, there are known, for example, ink-jet type recording heads used for image recording apparatuses, such as printers, color material ejection heads used for manufacture of color filters of liquid crystal displays, electrode material ejection heads used for electrode formation of organic electroluminescence (EL) displays and field luminescence displays (FED), and living body organic matter ejection heads used for manufacture of biochips (biotip), etc.
There are various forms of such a liquid ejection head. One exemplary form of the ink-jet type recording head (hereinafter, referred to as a recording head) in an ink-jet type recording apparatus (hereinafter, referred to as a printer) includes a channel unit fixed to a head case, the channel unit having a structure in which a nozzle substrate provided with a plurality of nozzle orifices, a channel substrate provided with a channel section such as pressure chamber cavities or grooves which define a series of ink channels from a common ink chamber down to the nozzle orifices through pressure chambers, and a resilient plate (also called a sealing plate which seals an opening of the channel substrate) which causes elastic deformation to diaphragm sections corresponding to the pressure chambers in response to the operation of a pressure generating means (for example, piezoelectric vibrator) are laminated. Of composition components of the channel unit, the channel substrate is required to be machined at a high density with high precision so as to respond to high density of a recorded image and high speed of recording operation. Accordingly, the channel substrate is suitably made of a crystalline base material such as silicon single crystal base material (silicon wafer) by which a fine shape can be formed by, for example, an anisotropic etching process with sufficient accuracy of dimension.
Accordingly, it is important to assemble the above-described composition components with high positioning accuracy in order to control the discharge operation of the recording head with high precision. Thus, JP-A-2001-30490 discloses a recording head whose composition components are laminated on and combined with each other in the state in which relative positions of all the composition components are specified in a manner such that composition components of a channel unit and a head case are provided with two through-holes which are positioning references and positioning pins are inserted in the two through-holes.
By the way, when a channel substrate is made of a crystalline base material as described above, the through-holes of this channel substrate are formed by etching like pressure chamber cavities. In this case in which there is a difference between the interval of the through-holes of the channel substrate and the interval of the through-holes of the head case, mechanical stress is applied to the channel substrate via the positioning pins due to the difference of the intervals, and thus there was the probability that the channel substrate cracks or breaks.


1. Field of the Invention
The present invention relates, in general, to an electric generator using a permanent magnet in a shape of a tapered cone, especially, one which induces a useful equilibrium of magnetic force and, more particularly, to a magnetically balanced electric generator, in which a power-generating core unit and a power-generating magnet are spaced apart at constant intervals using a magnetically repulsive force, which is caused by a permanent magnet shaped like a tapered cone, and a magnetically attractive force, which is caused between the power-generating core unit and a power-generating magnet, and the interval is controlled depending on the intensity of wind, thereby improving power-generation efficiency, the lifetime of parts, and economical efficiency of products.
2. Description of the Related Art
Generally, an electric generator means a device that includes a rotor which rotates under external force, a fixing structure supporting the rotor, and an electricity-generating unit which operates upon rotation of the rotor. However, bearings of such electric generators have a problem in that a certain amount of oil should be regularly supplied to the bearings and the contamination of foreign substances causes damage to the bearings.
Further, in case of wind turbines using wind power as an external force, an electrical-connection controller should be installed in order to generate electricity as expressed by the formula E=Cp×(½)×ρ×A×v3, which however is difficult work, and thus problems such as the complexity of parts, burning-out of electric parts or the like occur. Wind turbines are the hardest kinds of electric generators to design because they have to deal with energy proportional to cubic wind velocity.
Meanwhile, the applicant developed a new construction electric generator in consideration of the fact that existing vertical type wind generators do not sufficiently utilize wind power, which generator was disclosed in Korean Patent Registration No. 0743475.
FIG. 1 shows the structure of the electric generator in a cross-sectional view.
The disclosed electric generator is called a variable electric generator for a wind turbine, which includes a group 11 of magnets which is installed on a lower end of a rotor 10 rotating with the wind, a plurality of core units 21 which is installed in a fixing structure in such a manner as to be arranged concentrically with the magnets of the group and which upon rotation of the rotor 10 interacts with the magnets to thereby generate electricity, an anemometer 30 detecting the magnitude of wind velocity, an electric accumulator 40 storing electricity generated by the core unit 21, and a terminal 50 connecting the respective core units 21 and the electric accumulator together such that the core units are selectively connected with the electric accumulator according to the wind velocity detected by the anemometer 30.
The variable electric generator of this type changes a power-generating condition depending on the intensity of wind, having such advantages as more efficiently utilizing wind power.
In the meantime, in order to generate electricity using interaction between the power-generating magnet and the core unit, in which a coil is wound around a silicon steel plate, an interval between the power-generating magnet and the core unit should be maintained to approximately 1 mm. Then, since the interval is maintained by a spherical steel bearing 61, which is mounted between the rotor and the fixing structure, the bearing should be periodically lubricated so that the interval can be maintained accurately and efficiently, which is troublesome work, otherwise the bearing may burn out during use, problematically requiring replacement with new one.
Furthermore, problems such as contact points burning out during manipulation of the power-generating coil, which may result in a reduction in lifetime, may occur.


This invention relates generally to a multi-stage barrel type centrifugal pump and more particularly to a preassembled unit or cartridge forming an inner assembly for a multi-stage barrel type centrifugal pump having all working pump parts including bearings, seals, and thrust balancing device, as well as the impeller and diffuser adaptable for insertion in and removal from the fixed outer casing for the pump.
It is well known that in the replacement of the working parts of prior art multi-stage barrel type pumps that it is first necessary to dismantle and remove the bearing seals, balancing device and inner elements, then replace the required working parts, and then reassemble all the elements and associated parts for the pump.
The replacement and reassembly process requires adjustments in axial and radial rotor position to obtain satisfactory running clearances between the moving and stationary parts of the pump, and the overall process of element replacement requires many hours of labor in the field where labor rates tend to be high and during which time the pump is not available for service. One effort to meet and overcome this problem is shown in U.S. Pat. No. 3,927,763.
The present invention overcomes this problem of barrel type centrifugal pumps by providing a preassembled, adjusted and aligned unit or cartridge having all the working parts of the pump; i.e., bearings, seals, and balancing device as well as the impellers and diffusers; which can be installed or removed easily from the barrel or outer casing for the pump, and renewal of the pump merely requires the removal and installation of a preassembled replacement unit or cartridge.
The unit or cartridge concept is made possible by means of a special rig or frame which duplicates the pump casing in supporting the unit or cartridge. This permits all adjustments to be made and checking of the rotor for free rotation to be done before installation in the pump.
The fixture can also be moved to the assembly point near the pump and in this context acts as a carrier for transporting the cartridge.
Thus, precise assembly and adjustment can be made at the machine or service shop where more highly trained personnel are located and where labor charges are less costly.


Solid golf balls are typically made with a solid core encased by a cover, both of which can have multiple layers, such as a dual core having a solid center (or inner core) and an outer core layer, or a multi-layer cover having inner and outer cover layers. Generally, golf ball cores and/or centers are constructed with a thermoset rubber, such as a polybutadiene-based composition.
Thermoset polymers, once formed, cannot be reprocessed because the molecular chains are covalently bonded to one another to form a three-dimensional (non-linear) crosslinked network. The physical properties of the uncrosslinked polymer (pre-cure) are dramatically different than the physical properties of the crosslinked polymer (post-cure). For the polymer chains to move, covalent bonds would need to be broken—this is only achieved via degradation of the polymer resulting in dramatic loss of physical properties.
Thermoset rubbers are heated and crosslinked in a variety of processing steps to create a golf ball core having certain desirable characteristics, such as higher or lower compression or hardness, that can impact the spin rate of the ball and/or provide better “feel.” These and other characteristics can be tailored to the needs of golfers of different abilities. Due to the nature of thermoset materials and the heating/curing cycles used to form them into cores, manufacturers can achieve varying properties across the core (i.e., from the core surface to the center of the core). For example, most conventional single core golf ball cores have a ‘hard-to-soft’ hardness gradient from the surface of the core towards the center of the core.
In a conventional, polybutadiene-based core, the physical properties of the molded core are highly dependent on the curing cycle (i.e., the time and temperature that the core is subjected to during molding). This time/temperature history, in turn, is inherently variable throughout the core, with the center of the core being exposed to a different time/temperature (i.e., shorter time at a different temperature) than the surface (because of the time it takes to get heat to the center of the core) allowing a property gradient to exist at points between the center and core surface. This physical property gradient is readily measured as a hardness gradient, with a typical range of 5 to 40 Shore C, and more commonly 10 to 30 Shore C, being present in virtually all golf ball cores made from about the year 1970 on.
The patent literature contains a number of references that discuss ‘hard-to-soft’ hardness gradients across a thermoset golf ball core. Additionally, a number of patents disclose multilayer thermoset golf ball cores, where each core layer has a different hardness in an attempt to artificially create a hardness ‘gradient’ between core layer and core layer. Because of the melt properties of thermoplastic materials, however, the ability to achieve varied properties across a golf ball core has not been possible.
Unlike thermoset materials, thermoplastic polymers can be heated and re-formed, repeatedly, with little or no change in physical properties. For example, when at least the crystalline portion of a high molecular weight polymer is softened and/or melted (allowing for flow and formability), then cooled, the initial (pre-melting) and final (post-melting) molecular weights are essentially the same. The structure of thermoplastic polymers are generally linear, or slightly branched, and there is no intermolecular crosslinking or covalent bonding, thereby lending these polymers their thermolabile characteristics. Therefore, with a thermoplastic core, the physical properties pre-molding are effectively the same as the physical properties post-molding. Time/temperature variations have essentially no effect on the physical properties of a thermoplastic polymer.
As such, there is a need to achieve a single layer core that has a gradient from the surface to the center, and to achieve a method of producing such a core that is inexpensive and efficient. The gradient may be either soft-to-hard (a “negative” gradient) or hard-to-soft (a “positive” gradient). A core exhibiting such characteristics would allow the golf ball designer to create a thermoplastic core golf ball with unique gradient properties allowing for differences in ball characteristics such as compression, “feel,” and spin.


The present invention relates generally to electronic circuits. More particularly, the present invention provides an adjustable bandwidth phase-locked loop.
A phase-locked loop (PLL) 10 is an electronic circuit having a phase detector 12, an amplifier 14 and a voltage-controlled oscillator (VCO) 16 generally connected as shown in FIG. 1. The PLL can be used in a wide variety of applications, including: frequency demodulation (both AM and FM signals); frequency synthesis; frequency multiplication; tone decoding and frequency-shift keyed (FSK) decoders. The PLL is a useful building block available from several manufacturers as a single integrated circuit.
Phase detector 12 provides a comparison between the frequency of input signal 18 and VCO output signal 20, and generates an phase error signal 22 that is a measure of the phase difference between the two input frequencies. Phase error signal 22 may be filtered by a low pass filter 13 then amplified by amplifier 14 resulting in output signal 24. Output signal 24 is Provided as an input to VCO 16 and causes the frequency of VCO output signal 20 to deviate in the direction of the frequency of input signal 18. Filtering of phase error signal 22 smooths swings on the VCO output signal 20. VCO 16 locks on the input frequency maintaining a fixed phase relationship with input signal 18. VCO output signal 18 may be of a different type, e.g., square wave, sine wave or other waveform, than input signal 18. The frequency of VCO output signal 20 is a clean replica of the frequency of input signal 18, which itself may be noisy.
A PLL circuit may be characterized by two interrelated measurements of the PLL circuit performance: bandwidth and acquisition time. The speed at which the VCO output will lock to the input signal is referred to as the acquisition or settling time for the PLL. A PLL may be configured to operate with a fast settling time by adjusting filter 13. Filter 13 typically includes a series resistor and capacitor coupled between the output of phase detector 12 and ground. Many other filter configurations are used as known in the art. The filter is often referred to as a loop filter. The selection of values for the filter loop capacitors and resistors determines the closed loop bandwidth, and thus the settling time for the PLL.
Bandwidth refers to the range over which the VCO output signal may vary with respect to the input signal from initialization until a lock has occurred. The bandwidth of the PLL circuit has a direct effect on whether lock can be achieved on a given reference signal and how long the acquisition time will be. Bandwidth is directly proportional to the filtering of the phase error signal. The more filtering that is provided, in the form of large RC (or LC) time constants in filter 13, the slower the response of the VCO output signal to variations in the input reference signal. Lock is achieved very slowly or may never be achieved if too much filtering is provided. Conversely, settling times may be improved if less filtering is provided but the output of the VCO may vary and be susceptible to noise in the input signal.
A wide bandwidth PLL circuit typically provides faster acquisition time while narrow bandwidth systems are slower to achieve lock. Thus, conventional PLL circuits are not well suited for applications requiring both fast settling times as well as narrow bandwidth performance.
In general, in one aspect, the invention provides an adjustable bandwidth phase-locked loop including a phase-locked loop having a first input node receiving an input signal having a first frequency, a second input node receiving a feedback signal and an output node which has a signal indicative of an error signal characterizing a frequency error between the input signal and the feedback signal. The adjustable bandwidth phase-locked loop includes a voltage controlled oscillator, coupled to the second input node, receiving the error signal and generating the feedback signal where the feedback signal has a frequency which tracks the first frequency. The adjustable bandwidth phaselocked loop includes a variable loop filter, coupled between the phase-locked loop and the voltage controlled oscillator, filtering the error signal. The variable loop filter is configurable to allow for the tracking of the input signal over both of a broad bandwidth and a narrow bandwidth.
Aspects of the invention include one or more of the following features. The phase-locked loop may include a phase detector which detects differences between frequencies of the input signal and the feedback signal and generates the error signal indicative thereof. The voltage controlled oscillator may include an output signal that tracks the frequency of the input signal. The output signal may be a different form than the input signal.
The variable loop filter may include a narrowband loop filter, a wideband loop filter and a switch which switches the narrowband loop filter between the phase-locked loop and the voltage controlled oscillator in accordance with receipt of a bandwidth adjustment signal. The bandwidth adjustment signal may be generated by the phase-locked loop after acquisition of the input signal. A charging circuit may be included to pre-charge the narrowband loop filter to a potential equal to a potential developed across the wideband loop filter so that at a time for switching in the narrowband loop filter the adjustable bandwidth phase-locked loop maintains lock on the input signal. The charging circuit may include an operational amplifier configured as a follower.
The narrowband loop filter may include a first capacitor and the wideband loop filter may include a second capacitor. The charging circuit may pre-charge the first capacitor to a voltage level approximately equal to the voltage developed across the second capacitor, where the voltage developed across the second capacitor is in response to the error signal.
In another aspect, the invention provides an adjustable bandwidth phase-locked loop including a phase-locked loop having a first input receiving an input signal having a first frequency, a second input for receiving a feedback signal and an output for generating an error signal characterizing a frequency error between the input signal and the feedback signal. The phase-locked loop includes a voltage controlled oscillator receiving the error signal and generating the feedback signal where the feedback signal has a frequency which tracks the first frequency. A wideband loop filter is coupled between the phase-locked loop and the voltage controlled oscillator for filtering the error signal to allow for the tracking of the input signal over a broad bandwidth. A narrowband loop filter is provided for filtering the error signal to allow for the tracking of the input signal over a narrow bandwidth. A controllable switch element is provided, operable to change a mode of the narrowband loop filter between the phase-locked loop and the voltage controlled oscillator wherein the narrowband loop filter effectively minimizes the effect of the wideband loop filter resulting in the tracking of the input signal over a narrow bandwidth.
In another aspect, the invention provides a method of adjusting bandwidth of a phase-locked loop circuit where the phase-locked loop circuit includes phase-locked loop for receiving an input signal having a first frequency, a voltage controlled oscillator for generating a locally developed signal having a frequency which tracks the first frequency and a wideband loop filter coupled between the phase-locked loop and the voltage controlled oscillator for dampening the response of the voltage controlled oscillator to allow for the tracking of the input signal over a broad bandwidth. The method includes providing a narrowband loop filter to allow for the tracking of the input signal over a narrow bandwidth and switching in the narrowband loop filter between the phase-locked loop and the voltage controlled oscillator wherein the narrowband loop filter effectively minimizes the effect of the wideband loop filter resulting in the tracking of the input signal over a narrow bandwidth.
In another aspect the invention provides a method for quickly locking a narrow bandwidth phase-locked loop circuit where the narrow bandwidth phase-locked loop circuit includes a phase-locked loop for receiving an input signal having a first frequency, a voltage controlled oscillator for generating a locally developed signal having a frequency which tracks the first frequency and a narrowband loop filter coupled between the phase-locked loop and the voltage controlled oscillator for dampening the response of the voltage controlled oscillator to allow for the tracking of the input signal over a narrow bandwidth. The method includes providing a wideband loop filter to allow for the tracking of the input signal over a wide bandwidth and switching in the wideband loop filter between the phase-locked loop and the voltage controlled oscillator while switching out the narrowband loop filter resulting in the tracking of the input signal over a wide bandwidth. Once lock onto the input signal is acquired, the narrowband loop filter is switched back in between the phase-locked loop and the voltage controlled oscillator resulting in the tracking of the input signal over a narrow bandwidth.
Aspects of the invention provide numerous advantages. Applications for the use of PLL devices may be expanded by providing an adjustable bandwidth PLL device. The invention provides for a fast PLL phase or frequency acquisition while maintaining a reduced PLL bandwidth in narrow bandwidth applications. Acquisition time for a narrow bandwidth PLL circuit may be improved by providing an adjustable PLL circuit that switches from wide band to a narrow band performance after acquisition. Other features will be apparent from the following description and claims.


In modern telecommunications, control information and data are typically carried in separate regions of the subframe or packet. For instance, in third generation partnership project (3GPP) long term evolution (LTE) networks, control information is carried in a physical downlink control channel (PDCCH) and/or enhanced PDDCH (ePDCCH) of the subframe, while data/traffic is carried in a physical shared control channel (PSCCH) of the subframe. Additionally, pilot signals are oftentimes communicated contemporaneously with the data transmission in order to facilitate demodulation. More specifically, a pilot signal consists of a series or collection of known reference symbols (i.e., a priori information) which the receiver evaluates upon reception in order to estimate parameters (e.g., fading, scattering) of the air channel. In 3GPP LTE networks, pilot signaling is achieved through the inclusion of cell-specific reference signals (CRS) and/or demodulation reference signals (DMRS) within the subframe.
Data recovery techniques/processes allow receivers to obtain data carried by an earlier data transmission with which the receiver was unable to successfully demodulate/decode. Conventional data recovery techniques rely on either re-transmitting the entire original data transmission or otherwise communicating additional forward error correction (FEC) bits related to the entire original data transmission, e.g., via hybrid automatic repeat request (HARQ) signaling. For instance, one conventional data recovery technique may re-transmit substantially all of the data/traffic carried in the PDSCH region of an LTE subframe. Another conventional data recovery technique may re-transmit FEC bits pertaining to the entire PDSCH region of the LTE subframe. These conventional techniques may consume significant bandwidth, particularly when the original data payload was large or when poor channel conditions necessitate a relatively low coding rate. As such, more efficient mechanisms for recovering data are desired.


The present invention pertains to fiber optical current and voltage sensors and, more particularly, to applications involving filters for use in such sensors.
One important aspect of electrical power systems deployed by the power generation industry is the ability to measure power carried over high voltage transmission lines. Power measurement has typically been performed on the high voltage side of the systems before the voltage is stepped down for distribution. However, the need is growing for more frequent and more accurate power measurements (e.g., voltage and current measurements) throughout the power distribution systems. Some recent innovations associated with making such power measurements involve the use of fiber optic sensors as described in more detail in, for example, the above-incorporated by reference U.S. Patent Publication 2011/0204875.
There are a number of different electrical power systems which require such monitoring. For example, in nuclear power applications, standby power transformers are employed to run critical equipment in the case of a failure. Normally, these standby power transformers are unloaded, but the high side is connected. By keeping their high sides connected, standby power transformers can be quickly switched on when needed. However, there have been several incidents where these generators were not fully connected at the high side (i.e., they had an open-phase condition), and it was not known until the emergency power was needed. In response to this problem, the Nuclear Regulatory Commission in the United States is implementing a requirement that all such standby generators have monitoring equipment installed to detect the open phase condition.
If unloaded, the current flowing into the high side of such standby power transformers is substantially the current attributable to the magnetization current of the power transformer's core, e.g., typically on the order of less than one ampere such as 50 to 800 mA. Alternatively, if the standby power transformer is slightly loaded, e.g., due to the presence of a monitoring load, then the current flowing into the high side of the standby power transformer might be a bit higher, e.g., on the order of an ampere. Regardless, when in the undesirable open-phase condition, the current flowing into the high side of the standby power transformer will drop to approximately zero (there may still be some very small capacitive current).
Thus, in order to tell if a standby power transformer is properly connected or not, a monitoring system can be used to determine when the high side current flow drops below some predetermined threshold, e.g., 25 to 500 mA. In order to reliably measure such small currents, the current sensor must be able to resolve currents several times lower than the low-level threshold, or typically about 10 mA. This value may vary according to the specific transformer under consideration. One way to design an optical current sensor to be able to detect current levels as low as 10 mA is by using a combination of a large number of fiber sensing turns in combination with a number of wire wraps around the sensing fiber loops. For example, Alstom has fielded a product which employs 60 wraps of sensing fiber together with 10 wraps of the primary conductor, yielding a multiplication factor of the current of 600.
However, in some applications it is not practical to employ multiple wraps of the primary conductor around the fiber optic current sensor. Also, it is quite expensive to install a large number of sensing fiber turns (e.g., 600 fiber turns) in a single optical current sensor, which would be needed absent the multiplicative effect provided by the multiple wraps of the primary conductor around the fiber optic current sensor.
Another approach to providing an optical current sensor which can detect such low levels of current involves passing the output of the optical current sensor through a comb filter as, for example, described in U.S. patent application Ser. No. 12/598,651, entitled “Adaptive Filters for Fiber Optic Sensors, also referred to herein as U.S. Patent Publication 2011/0204875, the disclosure of which is incorporated here by reference. In U.S. Patent Publication No. 2011/0204875, the comb filter is triggered off the current waveform that itself is being filtered. The raw current passes through a narrow band pass filter around the largest frequency component to be measured (normally the fundamental frequency). The zero crossings of the waveform at the output of this filter are used to track the frequency of the signal, and thus to provide the reset function required in the comb signal processing.
The system described in U.S. Patent Publication No. 2011/0204875 is therefore limited in its ability to accurately track the frequency (and thus properly time the resets of the comb filter) when the signal-to-noise ratio becomes too low. At some low level of primary signal, the noise coming through the band pass filter substantially interferes with the zero crossings of the resultant signal, distorting their location, or even adding extraneous zero crossings. Thus the system described in U.S. Patent Publication No. 2011/0204875 suffers a limitation in its ability to recover a small signal from a large noise.
Accordingly, it would be desirable to provide optical current sensors, transformers, systems and sensing methods which address the foregoing issues.


The human heart is the muscle that is responsible for pumping blood throughout the vascular network. Veins are vessels that carry blood toward the heart while arteries carry blood away from the heart. The human heart consists of two atrial chambers and two ventricular chambers. Atrial chambers receive blood from the body and the ventricular chambers, which include larger muscular walls, pump blood from the heart. A septum separates the left and the right sides of the heart. Movement of the blood is as follows: blood enters the right atrium from either the superior or inferior vena cava and moves into the right ventricle. From the right ventricle, blood is pumped to the lungs via pulmonary arteries to become oxygenated. Once the blood has been oxygenated, the blood returns to the heart by entering the left atrium, via the pulmonary veins, and into the left ventricle. Finally, the blood is pumped from the left ventricle into the aorta and the vascular network.
For the vast majority of the population, the events associated with the movement of blood happen without circumstance. However, for many people the heart fails to provide adequate pumping capabilities. These heart failures may include congestive heart failure (commonly referred to as heart disease), which is a condition that results in any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump blood throughout the body. Presently, there is no known cure for heart disease and long-term treatment is limited to a heart transplant. With only a little over 2,000 patients receiving a heart transplant each year, and over 16,600 more on the waiting list for a heart, there is a persisting need for a cure or at the minimum a means of improving the quality of life of those patients on the waiting list.
One such means of bridging the time gap while awaiting a transplant is a circulatory assist system. Circulatory assist systems may also be utilized as a destination therapy for individuals not eligible for a heart transplant. These systems, originally envisioned over thirty years ago, provide assistance to the heart by way of a mechanical pump. In this way, blood is circulated throughout the vascular network despite the diseased heart tissue. Traditionally, these circulatory assist systems include an implantable or extracorporeal pump, a controller (internal or external), and inflow and outflow tubes connecting the pump to the heart and the vascular network. Food and Drug Administration (FDA) approved circulatory assist systems can partially relieve symptoms of breathlessness and fatigue associated with severe heart failure and drastically improve quality of life.
Implantable pumps may reside in a “pump pocket,” which is a subcutaneous or submuscular space on the chest of a patient, near the clavicle or shoulder. Once the inflow tube is connected to the heart, it normally resides within the thoracic cavity until connected with the pump. In order to access the chest cavity and reach the tube, practitioners must tunnel through the intercostal space adjacent the pump pocket. Once in the thoracic cavity, the practitioner is able to grasp the inflow cannula and direct it to the pump pocket for connection to the pump. When tunneling through the intercostal space, surgeons may resort to general surgical tools at their disposal, such as an anastomotic clamp or forceps. However, such tools may tear or otherwise injure the intercostal tissue when being forced into the intercostal space. Moreover, due to the high amount of force required to tunnel through the intercostal muscle, there is a risk of harming the patient, such as rupturing a vessel. Alternatively, surgeons may use a tunneling device to tunnel through the intercostal space. However, such tools must be able to securely grasp the inflow cannula and direct it to the pump pocket, while still being able to easily disconnect from the inflow cannula so that it may be connected to the pump. Therefore, there is a need in the art for a system and method which allows for a more controlled procedure of connecting a blood pump with the necessary tubing.


A tensioner lever is generally mounted, by means of a mounting bolt or pin, on an engine block or other frame, in the vicinity of a tensioner which cooperates with the lever. The tensioner lever, in cooperation with the tensioner, maintains appropriate tension in the transmission medium to prevent transmission failure due to excess tension and excess loosening of the transmission medium.
In one well-known example of a conventional tensioner lever, described in Japanese Laid-open Patent Publication No. 2001-323976 (pages 1 to 4, FIG. 2), a sliding contact portion extending along the traveling plane of the chain, and a reinforcing body, which reinforces the sliding contact portion, are fused together. In another example of a conventional tensioner lever, described in Japanese Utility Model Registration Publication No. 2540896 (pages 1 to 3, FIG. 1), the lever includes a resin shoe for sliding contact with the transmission chain, and an aluminum arm for supporting the resin shoe.
In the first of the above two conventional chain levers, the reinforcing body is strengthened by glass fibers. As the reinforcing body continues to pivot about a pivoting shaft on an internal combustion engine, the internal surface of its mounting hole is subject to wear, and the glass fibers are exposed and crushed. The crushed glass fibers act as an abrasive, causing accelerated wear and damage to the mounting hole of the reinforcing body and the pivoting shaft. In the case of a lever incorporating an aluminum arm, the continued pivoting of the lever about a pivoting shaft on an engine causes the arm to be burned and thereby also subjected to wear and damage. The use of a bushing or the like, fitted to the pivoting hole, has been considered to avoid the problem of wear. However, this measure increases the number of parts, the difficulty of assembly, and the production cost. Moreover, in the case of an aluminum arm, recycling of a spent lever is troublesome because the resin shoe, the aluminum arm, and a resin pad, must be separated before disposal.
Accordingly, the objects of the invention are to solve the above-described problems, and to provide a tensioner lever having excellent mechanical strength and wear resistance, reduced production cost, reduced weight, and ease of recycling. A particular object of the invention is to reduce wear on the inner circumferential surface and the boss portion of the pivoting hole by which the lever is mounted on the engine block.


As optical radar apparatuses capable of setting a detection area in a widthwise direction of a road surface, there are apparatuses such as those disclosed in Japanese Utility Model Laid-Open Nos. 59-117980 and 59-117981.
In the apparatus disclosed in Japanese Utility Model Laid-Open No. 59-117980, shown in FIGS. 7A and 7B, light from a light source is condensed to some extent by a lens to obtain a first detection range .theta.T1, and the light source is suitably moved to obtain a second detection range .theta.T2 wider than the first detection range .theta.T1 in a widthwise direction of a road surface by changing the degree of condensing of the lens.
In the apparatus disclosed in Japanese Utility Model Laid-Open No. 59-117981, shown in FIG. 8, light from a light source traveling through a lens is diffused by a prism to increase an expansion angle in a road surface direction, thereby setting a detection range wide in a widthwise direction of a road surface.
In the apparatus disclosed in Japanese Utility Model Laid-Open No. 59-117980 among the above-described conventional apparatuses, shown in FIGS. 7A and 7B, however, light cannot be emitted simultaneously for the first detection range .theta.T1 and the second detection range .theta.T2, and the detection range is set one-sidedly, since the detection range is changed by moving the light source.
The apparatus disclosed in Japanese Utility Model Laid-Open No. 59-117981, shown in FIG. 8, entails the problem of a reduction in the maximum detection distance because light is uniformly diffused by the prism. Because of this problem, it is not possible to meet a demand heretofore made for widening the detection range in a widthwise direction of a road surface in a short-distance area without reducing the maximum detection distance when an optical radar apparatus is used for an inter-vehicle control or an obstacle detecting apparatus.
The present invention has been achieved in consideration of the above-described problems, and an object of the present invention is to provide an optical radar apparatus capable of increasing the expansion angle in a road surface direction in a short-distance range without setting the detection range one-sidedly and without sacrificing the maximum detection distance.


Traditionally, computer software is manufactured and distributed through a system where a developer creates software (by designing a solution to a problem and coding that solution), manufactures the software in mass at a production facility, packages the software and then distributes it to the consumer. The software, in the form of computer code, is stored on a secondary storage device, such as a disk. Software products are generally manufactured by copying the computer code to the required number of storage devices. In a normal distribution chain, the consumer, who may be a purchaser or licensee, generally acquires the software (i.e., a storage device containing a copy of the computer code) from wholesale or retail dealers who in turn have acquired the software from the manufacturer.
A problem with the traditional system for the manufacture and distribution of computer software is that each software developer has its own substantial production, packaging and transportation costs, plus fixed overhead costs for facilities and personnel. When added to the initial investment required to develop software, such costs often make the launching of a new product prohibitive for the developer, especially where the developer is an individual or small corporation. Production and distribution is costly, and these costs are passed on to the consumer by way of higher product prices or fees. Additionally, the developer, where demand for a product is uncertain, may not know how many copies of a piece of software no manufacture and distribute. Production of too many or too few copies results in lost profits.
One approach taken by a segment of the software industry in order to reduce the inherent costs associated with the traditional manufacture and distribution of software is to invite consumer participation through the concept of "shareware" software. Shareware is software available for copying by consumers free of charge or at nominal costs from electronic bulletin boards accessed using modems or through mail order catalogue services. If, after having had an opportunity to use the software for a short period of time, the user decides to keep the software, the user is then under a good faith obligation to register the software and return a fee to the developer or distributor. In practice, the consumer participation in copying and distributing the available software is good, but the honorarium is rarely paid. As a direct consequence of the poor returns to shareware developers in general, the quality of products and level of support is low.
Another and very significant problem facing the manufacturer of computer software is the unauthorized reproduction of software products. Computer software is expensive to design and code, but the duplication of an individual piece of software can be done swiftly and, relative to the initial production costs, at minimal cost. For example, by using operating system commands, a user can simply copy a program from a storage device such as a disk using one of the user's disk drives to another storage device. This illegal copying of software duplicates, on a small scale, a developer's manufacturing process. However, the unauthorized copying of computer software cannot be controlled by the manufacturer and the distribution of authorized copies cannot be traced.
The software manufacturing industry is placed in an unfortunate position. The purchase price of software is relatively high to reflect the cost of design and coding. The consumer is often averse to paying a high price for software, especially for software that cannot be evaluated before purchase (because the manufacturer will not allow access to the software before the purchase to prevent pre-purchase copying), and when the consumer is faced with a low risk of being detected and prosecuted for copying software, there is a strong incentive to make an unauthorized copy of the software. In effect, unlicensed, pirated software competes directly for the same market as legally manufactured software. The lost revenue to the manufacturer is passed on to the consumer via higher purchase prices, further increasing the incentive for piracy. With the current trend in the industry to develop software which has an intuitive, graphical interface, not requiring manuals to operate it, this problem can only increase as users do not require access to difficult to copy instruction manuals and tutorials. Further, pirated software can be quickly and widely distributed over telephone lines using modems.
One approach the industry has taken to improve the return on investment in the manufacture and distribution of software is to attempt to decrease the amount of software piracy. Software developers have used varying copy protection schemes. These schemes generally prevent a user from copying software or using an unauthorized copy of software. Schemes include "dongles", "code-wheels", storing the software on difficult to copy storage devices such as copy protected disks, using enabling access codes provided in user manuals or by the developer that must be entered before the software will work, or using hardware specific validation codes that allow a piece of software to operate only on one identified computer. Alternatively, a software developer could use a hardware copy protection scheme where an access code is supplied by a unique or difficult to copy hardware device able to be attached to only one computer at a time. Typically, when licensed software is not given an access code, the standard practice is for the software to refuse to operate. See, for example, U.S. Pat. Nos. 4,562,306 (Method and Apparatus for Protecting Computer Software Using an Active Coded Hardware Device) and U.S. Pat. No. 4,748,561 (Method of Protecting Computer Software).
Copy protection schemes have not been effective in stemming the tide of piracy, mainly because there are many specialized anti-copy products available to "unlock" the copy protection. Further, some copy protection schemes prevent consumers from legitimately making backup copies of the software for use when the authorized copy fails or is destroyed.
Another approach to prevent piracy of software is to require the authorized user, upon the first start-up of the software, to input the user's name (which is then stored in the software's code) such that the user's name will appear on the initialization screen on each successive re-use in order to identify the user to whom the software is licensed or sold. This practice is intended to discourage authorized software users from allowing their software to be reproduced, knowing that they can be identified readily from an unauthorized copy of the software. However, as the software producer is unlikely to know when the software is illegally copied and is unlikely to be able to track down unauthorized users, such a scheme does not discourage copying. Further, there is no identification of users who pirate pirated software.
An approach to reduce piracy prior to purchase but to allow a potential consumer to test a piece of software is to distribute demonstration software without the full functional features of the software program. This permits the user to sample the user interface and certain features of the software without having to purchase the software product "sight unseen". If the user likes the software, the user can contact the developer or distributor for the fully functional software upon registration and payment of a license fee or the purchase price. The problem with such demonstration software is that twice the number of software products have to be produced and distributed. One or more storage mediums containing software must be produced and distributed for demonstration and one or more storage mediums containing different software must be produced and distributed for full function operation. This increases the costs of production and distribution. Further, the user is inconvenienced by twice having to contact or visit the distributor and is delayed until the full function software is obtained.
One solution to the problem of having to obtain additional fully functional software is to initially provide to the user the full function program but to have only certain files active for demonstration purposes. Then, if the user wants to enable the full function, the user must contact the developer or distributor for registration and payment of the license fee or purchase price in return for an access code. However, once the access code is revealed, unauthorized copies can be made and the access code can be passed on with the unauthorized copy of the software. Therefore, this is not effective protection. Typically the process also requires the overhead of serializing each individual software copy at a central point of manufacture.
As a result of the high overhead costs of the traditional means of manufacture and distribution of software, and the significant level of unauthorized reproduction of software, there is a meed in the software industry for a system that takes advantage of the software consumers' ability to manufacture and distribute copies of software using their own equipment while at the same time controlling access to the software so that the person who designed and coded the software receives fees for its use. In other words, there is a need in the industry for a method of manufacture and distribution that invites rather than restricts consumer participation in the manufacture and distribution process but does not reduce the incentive of the original manufacturer to create the software.
Software is not the only product that suffers from these problems. Other developers and distributors in the information industry, such as developers and distributors of databases and other informational products, also have difficulties controlling access to their product where it can be loaded onto a user's own machine. They have a product that individual users find easy to copy and distribute, but which is costly for the developer to initially design, make and efficiently distribute. Developers and distributors of information products desire to harness the user's ability to copy and distribute their product but only where they can obtain a fee for their initial involvement.
As a result, there is a significant and substantial need in the information industry to allow developers to sell their information product to the full potential market efficiently, that encourages and takes advantage of consumer participation in the manufacture and distribution of the information products yet has centralized monitoring and control, that permits consumers to evaluate the product prior to the purchase decision, that effectively combats piracy, and that permits developer profit for funding of support and update services.


Many underdeveloped areas may not have access to broadband services such as satellite location services. Infrastructure expenses may prevent improvement in such areas.
Many aerial platforms such as airplanes and drones or Unmanned Aerial vehicles (UAVs) have been or will be deployed in various regions around the world for broadband access. Such platforms may be deployed in a more cost effective manner than typical satellite networks.
Thus, there is a need for an efficient way to determine location of and/or track elements using aerial platforms.