Arc discharge in aqueous electrolytes (for example, welding under seawater), is widely used in engineering and construction, and is at present the only known form of stationary plasma discharge in liquid media. In recent years, such discharge was also used in different physicochemical studies and in the synthesis of various materials. The specific feature of arc discharge in liquid media is the localization of a plasma region near the electrode ends and a “falling” form of volt-ampere characteristic as illustrated in FIG. 1.
In a gaseous phase, different kinds of discharges can be implemented, the external manifestation and electrical parameters of which are connected with a wide range of technical characteristics for devices used in their implementation and a variety of elementary processes determining the conditions of current passage through gas. The essential feature of electric discharge development in the gaseous phase is a profound effect of the properties of the gas medium on the current passages through the gas.
Under usual conditions, the concentration of charge carriers (electrons and ions) in the gas is very low: a gas is a very good dielectric. For a gas to have a high electrical conductivity (as a result of ionization) it is necessary for a high quantity of charge carriers to be present, requiring in turn a great quantity of energy. Gases have a steady electric conductivity when there is equilibrium between the origination and disappearance of charges. Thus, to create a means by which high electrical conductivity in a gas can be achieved through substantially lower energy requirements than has been taught in the prior art is highly desirable.
If the rate of movement of electrical charges is proportional to the field strength, the conductivity of gas approximately obeys Ohm's law (FIG. 2, section a). With increasing field strength, the decrease of electrical charges begins to have an influence (FIG. 2, section b) because of the migration of the charges to the electrodes. Further increases of the electrical field strength result in a steep increase of current due to the start of collision ionization (FIG. 2, section c). In spite of the avalanche-like character of current increases, the existence of external ionizer(s) is needed to sustain the electrical discharge, and the discharge remains being as not self-sustained (region 1). Eventually, a point is reached where for each electron leaving the cathode, one or more electrons arrive at the anode, in a phenomenon known as breakdown discharge (glow discharge or plasma discharge). This causes a self-sustained electrical current from the cathode to the anode. However, the current state-of-the-art process requires a large amount of energy to reach this self-sustaining threshold. Since high energy requirements directly and indirectly decrease the overall economy of the model, the requirement of high energy is undesirable. Therefore, it is highly desirable to have a new process having low energy demand in which the transition from non self-sustained discharge to self-sustained discharge (glow discharge) would occur with a low-energy input.
Again referring to FIG. 1, which illustrates the prior art, the voltage-current characteristic curve for glow discharge preferably comprises three sections, referred to for the sake of clarity as subnormal section or subnormal mode (FIG. 2, section d), normal section or normal mode (FIG. 2, section e) and abnormal section or abnormal mode (FIG. 2, section f).
Further increase of current density on the cathode causes the appearance of electric arc, as well as a drastic change of the main characteristics of the discharge (FIG. 2, section g).
It should be noted that the appearance or threshold of discharges in the gas phase depends considerably on the pressure of the gas. Thus, in the case of a uniform field of breakdown voltage (self-maintained discharge initiation voltage) the threshold is determined by the product of pressure by the distance between the electrodes, according to Paschen's Law. Pachen determined that breakdown voltage is determined by the following equation:
  V  =            a                    (        pd        )                            ln                          (          pd          )                    +      b      where V is the breakdown voltage in Volts, p is the pressure in atmospheres, d is the gap distance in meters, and a and b are constants that depend upon the particular gas between the electrodes. Thus, in contrast to liquids, which are relatively incompressible, different forms of electric discharge can be implemented in gases by varying the pressure of the gas between the electrodes.
Moreover, when ultrasonic cavitation, a sort of “cold boiling” resulting from the creation and collapse of zillions of microscopic bubbles in the liquid caused by ultrasonic waves, is implemented within a liquid, its phase composition and physical properties abruptly change, which can lead to some specific features for the formation of electric discharges within the liquid. In the region of intense cavitation, a gaseous component is formed which represents a significant fraction of the liquid. Therefore it can be assumed that the conditions for electric breakdown into the cavitation region should become easier, and the initiation of different forms of discharge could start through use of this invention. By varying the parameters of an ultrasonic field, it is possible to influence the processes of plasma glow within a cavitating liquid.
The prior art has several examples of attempts to resolve this problem.
However, few patent applications or patents work in the abnormal mode. In abnormal mode, also known as abnormal glow, effectively all of the gas molecules must be ionized to provide charge carriers for the current. Typically, the gas molecules are ionized multiple times meaning that more than one electron has been freed for most of the gas molecules. This creates a relatively uniformly distributed plasma across the electrodes. A higher density (or pressure) of gas molecules, on the other hand, would lead to a normal mode, or normal glow discharge. In this region, fewer than all of the molecules are ionized. This creates a situation where plasma forms in a relatively small region between the electrodes. A plasma discharge of this type can lead to concentrated energy in a relatively small area and possibly lead to electrode damage. Therefore, it is preferable to work in the abnormal mode.
Those patent applications or patents that do work in the abnormal mode, like U.S. Pat. No. 5,068,002, to Monroe, do not use an electrode as the radiator, in the same way that the instant application uses it, whereby the current application discloses a very low energy consumption jointly with a very low voltage to initiate and maintains a volumetric discharge which generates operational advantages in term of achieving the goals of this application. Monroe describes an ultrasonic glow discharge surface cleaning apparatus for abrading contaminants from the surface of a work piece using plasma glow discharge.
For example, in US Patent Application 2004/0265137 A1 to Bar-Gadda, a method is proposed for hydrogen production from water or steam by means of plasma discharge excited in the UHF, radio- or low-frequency range, as well as with arc discharge. This application describes the injection of water molecules into plasma discharge.
U.S. Pat. No. 7,070,634 B1 A1 to Wang describes a plasma apparatus for converting a gaseous mixture of water vapor and hydrocarbons into hydrogen.
US Patent Application 2006/0060464 to Chang teaches a fluid phase contained in a reactor, within which electrodes (anode and cathode) are placed. A flow of gas bubbles is introduced or generated in the medium in the region adjacent to the cathode. The potential difference necessary for the initiation of glow discharge and for the ionization of gas molecules in the bubbles is applied between the cathode and the anode.
U.S. Pat. No. 7,067,204 to Nomura et al., describes an apparatus comprising an ultrasonic generator for creation of bubbles within a liquid, and a generator providing the excitation of electromagnetic waves in the liquid phase, for the implementation of the plasma discharge.
Japanese Application JP2006273707 to Shibata et al. relates to the publication, “Synthesis of amorphous carbon nanoparticles and carbon-encapsulated metal nanoparticles in liquid benzene by an electric plasma discharge in ultrasonic cavitation field,” Ultrasonic Sonochemistry 13 (2006) 6-12, Institute of Multidisciplinary Research for Advanced Material (IMRAM), Tohoku University. This application illustrates a method and a device for producing a nanocarbon material that does not require an expensive production facility such as the ones normally required for dry treatment. It can easily produce the nanocarbon material because the application of high voltage is not needed and neither worsens nor deteriorates the working environment in a production premise, and at the same time considers safety factors. This method can remarkably reduce production costs by improving production efficiency because of its continuous production and recovery, and providing an alternative for mass productivity. The method comprises a process (A) for arranging electrodes, one cathode and one anode, connected to the power source; an ultrasonic horn connected to an ultrasonic generator within an organic solvent that fills a container; and a process (B) for generating an ultrasonic cavitation field by ultrasonic waves into the organic solvent, around the head of the ultrasonic horn; and effecting the thermal decomposition of the molecules in the organic solvent by applying a voltage to the electrodes so as to generate plasma discharge within the ultrasonic cavitation field adequate for the production of the nanocarbon material.
U.S. Pat. No. 6,835,523 to Yamazaki et al. describes a “Method for fabricating with ultrasonic vibration a carbon coating,” which is a process for fabricating a carbon coating in a medium disposed on one side of an electrode connected to a high-frequency power supply. Ultrasonic vibrations are then supplied to the object.
None of the prior art, however, either individually or in combination, provides a method by which initiating and maintaining an abnormal glow volumetric sonoplasma discharge can be performed using a substantially lower amount of electrical power.
Thus there has existed a long-felt need for a method by which the sonoplasma discharge can be initiated and maintained with substantially less electrical power than is currently needed to accomplish the same result using the prior art. This is accomplished with this invention.
The current invention provides just such a solution by having a method and apparatus for initiating and maintaining an abnormal glow volumetric sonoplasma discharge (VSPD). With certain parameters of the electrical discharge and of the intensity of elastic vibrations, it is possible to initiate VSPD within a cavitating liquid medium. The mechanism for the initiation of VSPD is related to the breakdown of gas-phase microchannels formed by the growth cavitation bubbles. The method uses elastic vibrations (EV) in the frequency range 1,000-100,000 Hz with enough intensity for the development of cavitation phenomena; these vibrations are introduced into the liquid-phase working medium, and a source of direct, alternating (hertz and kilohertz range), high frequency (HF) (megahertz range) and ultrahigh frequency (UHF) (gigahertz range) electric field in liquid (DPS) provides the initiation and stable glow of VSPD. Resulting VSPD is characterized by volumetric glow in the frequency range of visible light and ultraviolet radiation in the entire cavitation-electric field, and is characterized by a rising volt-ampere characteristic curve.
When a high-intensity ultrasonic field exceeding a cavitation threshold is induced within liquids, a new form of electric discharge is obtained, characterized by a volumetric glow electrical discharge throughout the space between the electrodes, having a rising volt-ampere characteristic curve that is inherent to abnormal glow discharge in gas. Such discharge within the liquid has the surface characteristic of micro bubbles, and can be used for the design of novel sonoplasma-chemical processes because of the extensive interface plasma. The heterogeneous liquid/gas-vapor system leads to a rise in diffusion rates of chemically active particles in the system and a more economical method to achieve the desired result(s).


Over the last two decades, mass spectrometry has made tremendous strides in analyzing protein samples derived from a variety of different sample types. Coupled with electrospray ionization and various separation techniques, thousands of proteins may be identified and quantitated in a single sample. The most common approach used in the laboratory today involves some form of protein extraction followed by proteolytic digestion of protein sample of interest. The use of proteolytic enzymes like trypsin produces peptides that can easily be analyzed by a variety of different instrument configurations. This approach termed “bottom-up” proteomics, can be used to study the state of living cells as a function of their environment. One of the major advantages of the “bottom-up” approach is that the peptides produced have very similar physiochemical properties which makes for a straight forward separation of thousands of peptides in complex samples. Any separation approach coupled with tandem mass spectrometry can then be used to produce amino acid sequence information that is utilized to identify the proteins in a given sample. Although this technique is routine in many laboratories, there are limitations as to the amount of information that can be obtained when reducing intact proteins to their constituent peptides.
In contrast to “bottom-up” proteomics, “top-down” proteomics refers to methods of analysis in which protein samples are introduced intact into a mass spectrometer, without enzymatic, chemical or other means of digestion. Top-down analysis enables the study of the intact protein, allowing identification, primary structure determination and localization of post-translational modifications (PTMs) directly at the protein level. Top-down proteomic analysis typically consists of introducing an intact protein into the ionization source of a mass spectrometer, fragmenting the protein ions and measuring the mass-to-charge ratios and abundances of the various fragments so-generated. The resulting fragmentation is many times more complex than a peptide fragmentation, which may, in the absence of the methods taught herein, necessitate the use of a mass spectrometer with very high mass accuracy and resolution capability in order to interpret the fragmentation pattern with acceptable certainty. The interpretation generally includes comparing the observed fragmentation pattern to either a protein sequence database that includes compiled experimental fragmentation results generated from known samples or, alternatively, to theoretically predicted fragmentation patterns. For example, Liu et al. (“Top-Down Protein Identification/Characterization of a Priori Unknown Proteins via Ion Trap Collision-Induced Dissociation and Ion/Ion Reactions in a Quadrupole/Time-of-Flight Tandem Mass Spectrometer”, Anal. Chem. 2009, 81, 1433-1441) have described top-down protein identification and characterization of both modified and unmodified unknown proteins with masses up to ≈28 kDa
An advantage of a top-down analysis over a bottom-up analysis is that a protein may be identified directly, rather than inferred as is the case with peptides in a bottom-up analysis. Another advantage is that alternative forms of a protein, e.g. post-translational modifications and splice variants, may be identified. However, top-down analysis has a disadvantage when compared to a bottom-up analysis in that many proteins can be difficult to isolate and purify. Thus, each protein in an incompletely separated mixture can yield, upon mass spectrometric analysis, multiple ion species, each species corresponding to a different respective degree of protonation and a different respective charge state, and each such ion species can give rise to multiple isotopic variants.
The process of analyzing intact proteins in cell lysates by mass spectrometry (MS) is associated with a number of difficulties. Firstly, electrospray ionization (ESI) of protein mixtures from cell lysates can generate extremely complex mass spectra due to the presence of multiple proteins, each comprising its own charge state envelope, where each charge state envelope is the collection of mass spectral lines corresponding to plural charge states, and where each charge state correlates directly with the number of positively charged protons that are adducted to an otherwise charge-free molecule. Consequently, multiple charge state envelopes may be overlapping within any given mass-to-charge (m/z) range. In this example, multiple proteins overlap at the same m/z value that have different molecular weights and charges. Commonly used techniques in MS are often insufficient for simplifying these spectra because of the inherent peak overlapping as well as the inherent wide range of magnitudes of MS lines of ionized constituents, where such constituents may range from uninteresting small molecules to interfering biomolecules to the proteins of interest, themselves. Isolation of a specified charge state of a protein within such complex spectra does not typically alleviate the burden of multiple protein peaks overlapping, since the isolation of ions of a particular protein charge state will generally result in co-isolation of one or more additional ions. This co-isolation makes it a challenge not only to dissociate the protein in an attempt to identify it based on the fragments produced, but also to accurately determine the intact mass and sequence coverage of that protein.
So-called “front-end” separation techniques, such as liquid chromatography (LC) or ion mobility spectrometry (IMS), performed prior to introduction of samples into a mass spectrometer, may be implemented to reduce the overall complexity and provide an additional major benefit, which is the reduction of ionization competition at an ionization source. Unlike mixtures of proteolytic peptides typically analyzed in bottom-up experiments, intact proteins mixtures contain a wide range of molecular weights, isoelectric points, hydrophobicities, and other physiochemical properties that make it challenging to analyze these mixtures via any single separation technique in a comprehensive manner. Both of the above separation methods are associated with their own benefits and pitfalls. Liquid chromatography tends to require significant amounts of time per sample to separate individual proteins, although it is still common to have two or more proteins co-elute. Enhanced separation can reach the point of becoming more of “an art” than a standardized method, and the enhanced separation may be dependent on the user skill in the state-of-the-art. The latter technique, IMS, can rapidly separate certain proteins and/or charge states from others but IMS spectra are at least partially correlative with (i.e., not “orthogonal to”) mass spectra. The IMS method also suffers from ionization competition, requires extensive optimization and typically involves dynamic conditions to observe a full mass spectrum containing all charge states.
Proton transfer reactions, a type of ion-ion reaction that has been used extensively in biological applications for rapid separations of complex mixtures, addresses many of these aforementioned concerns. Experimentally, proton transfer is accomplished by causing multiply-positively-charged protein ions from a sample to react with introduced singly-charged reagent anions so as to reduce the charge of the multiply-charged protein ions. These reactions proceed with pseudo-first order reaction kinetics when the anions are present in large excess over the protein ion population. The rate of reaction is directly proportional to the square of charge of the protein ion (or other multiply-charged cation) multiplied by the charge on the anion. The same relationship holds for reactions of the opposite polarity as well. This produces a series of pseudo-first order consecutive reaction curves as defined by the starting multiply-charged protein ion population. Although the reactions are highly exothermic (in excess of 100 kcal/mol), proton transfer is an even-electron process performed in the presence of 1 mtorr of background gas (i.e. helium) and thus does not fragment the starting multiply-charged protein ion population. The collision gas serves to remove the excess energy on the microsecond time scale (108 collisions per second), thus preventing fragmentation of the resulting product ion population.
Proton transfer reactions (PTR) have been used successfully to identify individual proteins in mixtures of proteins. This mixture simplification process has been employed to determine charge state and molecular weights of high mass proteins. PTR has also been utilized for simplifying product ion spectra derived from the collisional-activation of multiply-charged precursor protein ions. Although PTR reduces the overall signal derived from multiply-charged protein ions, this is more than offset by the significant gain in signal-to-noise ratio of the resulting PTR product ions. The PTR process is 100% efficient leading to only single series of reaction products, and no side reaction products that require special interpretation and data analysis.
Various aspects of the application of PTR to the analysis of peptides, polypeptides and proteins have been described in the following documents: U.S. Pat. No. 7,749,769 B2 in the names of inventors Hunt et al., U.S. Patent Pre-Grant Publication No. 2012/0156707 A1 in the names of inventors Hartmer et al., U.S. Pre-Grant Publication No. 2012/0205531 A1 in the name of inventor Zabrouskov; McLuckey et al., Anal. Chem. 1998, 70:1198-1202; Stephenson et al., J. Am. Soc. Mass Spectrom. 1998, 8:637-644; Stephenson et al., J. Am. Chem. Soc. 1996, 118:7390-7397; McLuckey et al., Anal. Chem. 1995, 67:2493-2497; Stephenson et al., Anal. Chem. 1996, 68:4026-4032; Stephenson et al., J. Am. Soc. Mass Spectrom. 1998, 9:585-596; Stephenson et al., J. Mass Spectrom. 1998, 33:664-672; Stephenson et al., Anal. Chem., 1998, 70:3533-3544 and Scalf et al., Anal. Chem. 2000, 72:52-60. Various aspects of general ion/ion chemistry have been described in McLuckey and Stephenson, Mass Spec Reviews 1998, 17:369-407 and U.S. Pat. No. 7,550,718 B2 in the names of inventors McLuckey et al. Apparatus for performing PTR and for reducing ion charge states in mass spectrometers have been described in U.S. Pre-Grant Publication No. 2011/0114835 A1 in the names of inventors Chen et al., U.S. Pre-Grant Publication No. 2011/0189788 A1 in the names of inventors Brown et al., U.S. Pat. No. 8,283,626 B2 in the names of inventors Brown et al. and U.S. Pat. No. 7,518,108 B2 in the names of inventors Frey et al. Adaptation of PTR charge reduction techniques to detection and identification of organisms has been described by McLuckey et al. (“Electrospray/Ion Trap Mass Spectrometry for the Detection and Identification of Organisms”, Proc. First Joint Services Workshop on Biological Mass Spectrometry, Baltimore, Md., 28-30 Jul. 1997, 127-132).
The product ions produced by the PTR process can be accumulated into one or into several charge states by the use of a technique known as “ion parking”. Ion parking uses supplementary AC voltages to consolidate the PTR product ions formed from the original variously protonated ions of any given protein molecule into a particular charge state or states at particular m/z values during the reaction period. This technique can be used to concentrate the product ion signal into a single or limited number of charge states (and, consequently, into a single or a few respective mass-to-charge [m/z] values) for higher sensitivity detection or further manipulation using collisional-activation, ETD, or other ion manipulation techniques. Various aspects of ion parking have been described in U.S. Pat. No. 8,440,962 B2 in the name of inventor Le Blanc and in the following documents: McLuckey et al., Anal. Chem. 2002, 74:336-346; Reid et al., J. Am. Chem. Soc. 2002, 124:7353-7362; He et al., Anal. Chem. 2002, 74:4653-4661; Xia et al., J. Am. Soc. Mass. Spectrom. 2005, 16:71-81; Chrisman et al., Anal. Chem. 2005, 77:3411-3414 and Chrisman et al., Anal. Chem. 2006, 78:310-316.
Another difficulty associated with the mass spectrometric analysis of proteins in cell lysates by (MS) is that the fragmentation behavior for each charge state of a protein is generally unknown prior to the dissociation event. In particular, ions comprising some charge states can dissociate well while ions comprising other charge states may dissociate poorly. Isolation and dissociation of ions of a particular charge state therefore does not guarantee efficient dissociation or dissociation into a set of diagnostic fragments.
A third challenge associated with intact protein analysis is the wide distribution of charge states produced for high molecular weight proteins typically in excess of 50 kDa. Here the starting signal can be divided into over 30 plus charge states, making tandem mass spectrometry of any given charge state produce a spectrum with low signal-to-noise ratio. The ability to produce ample sequence coverage for protein identification can therefore be difficult with a single tandem mass spectrum.
A variety of ion activation (fragmentation) techniques can be used to produce structural information on intact proteins. The most commonly used approach termed collision-induced dissociation (CID) involves collisions of an isolated population of multiply-charged precursor ions with a neutral background gas. Most commonly, the multiply-charged precursor ions are accelerated using the fundamental frequency of motion of the defined ion population in order to collide with the neutral background gas so as to produce unimolecular dissociation events. This process leads to fragmentation along the amide backbone of the protein thus yielding amino acid sequence information. More extensive fragmentation of proteins can be obtained with higher collision energy processes termed HCD or high energy collision induced dissociation. Many times this involves multiple fragmentation events inside the collision cell thus producing more extensive sequence coverage. Another approach used to produce protein sequence coverage via ion activation is that of photodissociation (PD), where photons of a defined wavelength are used to excite the ion of interest. Two common types employed include ultra-violet (UV-PD) and infrared multiphoton dissociation (IRMPD). The latter is a high energy process where the rate of energy deposition in the ion far exceeds that of the dissociation process. Here fragmentation can be produced along any point in the protein backbone, or may yield amino acid side chain fragmentation as well. For IRMPD, this is a much lower energy process that is characterized by the presence of cleavages at amide bonds and losses of ammonia and water from the intact protein and fragment ions generated during irradiation. The time frame of the IRMPD experiment can be expanded to produce more extensive fragmentation as well. Ion-ion reactions using electron transfer reagent ions can also be employed as a fragmentation approach for intact proteins. Here an electron transfer event from the multiple-charged protein to the singly-charged anion produces backbone fragmentation of the protein with any posttranslational modifications still intact.
Taken together, these ion activation approaches for tandem mass spectrometry produce many different complementary forms of fragmentation that can provide protein sequence information. Ideally, these approaches can be applied in a broad band fashion in order to increase sequence coverage of proteins and provide additional information on modifications, splice variants, and expression of single amino acid mutations. The application of these approaches in a broadband format (i.e. covering multiple charge states of the same intact protein) would provide a more comprehensive view of protein characterization and identification.


1. Technical Field
The present device is a system for protecting windows, doors, and similar openings to a building against hurricane-force winds, more particularly a system comprising specially designed wedge brackets, bolts or screws that project year-round from the corners the openings, and a protective panel of sufficient size to cover the opening.
2. Background Information
An estimated six million single and double family dwellings, and many more commercial buildings, along United States coastlines are potentially affected by hurricanes as they spin their way up across the Atlantic Ocean or up through the Gulf of Mexico. As a hurricane bears down, homeowners and business people frequently prepare by nailing or screwing wooden boards up over windows and doors. Preparations are particularly feverish when a Category 4 or 5 hurricane is expected to make landfall. When a hurricane is expected to make landfall in the vicinity, the lines at lumber stores often stretch out into the parking lot and supplies of wooden boards, screws, and the like often run out. At the same time they are trying to protect their homes and valuables from the approaching hurricane, many people are simultaneously trying to pack up their children, elderly relatives, pets, clothing, photos, and other items to travel out of the path of the storm. They are concerned about getting out of the area before traffic jams occur. An easier, quicker system for protecting their homes and businesses is therefore much needed.
The present invention is a system for the homeowner or business person to use to protect their residences and other buildings from wind and rain damage. Anyone who is capable of lifting a board can implement this system over the windows and doors of a building.


There are two quite different types of electronic networks that are evolving: a standard telephone network and a data network (e.g., the Internet). The standard telephone network, such as a wireless telephony network and the POTS network, is designed to carry real-time messaging content. Capacity is allocated in real-time bandwidth and, once you have a connection of adequate bandwidth established between two points, data that is delayed is viewed as a network fault. Examples of communications that may be carried via a standard telephone network(s) include voice communications, multi-party conference calls, video conference calls, or the like.
Another characteristic of standard telephone networks is that each network is typically owned and controlled by a small number (typically a single company in the case of wireless networks) of large companies that historically have provided service directly to end users of the network and therefore have a billing type relationship with them. Where a connection is made through the facilities of another provider, there is typically a commercial contract in place between the two companies. These standard telephone networks, in part because of the relatively close relationship between the service vendors and network users, have the characteristic that the originator of a call can be readily identified, allowing “caller ID” service to be readily implemented and to be widely known and in fact expected.
In contrast, the second type of network (e.g., data networks such as the Internet, LANs, WANs, VPNs, and the like) were designed to move mostly one-way, non-real time data from point to point. In this type of network, the delay of data has typically not been regarded as a network fault. Additionally, some data networks, particularly the Internet, are far more disjoint than a standard telephone network. There are many more companies involved, and there is much less control of individual point-to-point end-user connections. It is typical that a company that provides transmission of data on the Internet has a tenuous commercial relationship with the originators of most of the data packets that it is carrying. In fact, Internet service providers (ISPs) protect the privacy and anonymity of their subscribers.
This tenuous commercial relationship with end users coupled with the relative ease with which the end-user computers that originate much of the traffic on the Internet can be anonymously enlisted in the service of third parties, leads to the fact that a “caller ID” type service is nearly impossible to implement on the Internet.
In recent years, these data networks have begun to evolve to provide real-time, two-way communications between parties. The communications may include, for example, voice-over-IP (VOIP), instant messaging, interactive video conferencing (e.g., web meetings), or the like.
Using the electronic data networks for real-time, two-way communications provide several advantages. In particular, using these electronic networks for real-time, two-way communications is relatively low cost and easily accessible. The proliferation of networks throughout today's society, particularly the Internet, has ensured ready access to a communications device capable of communicating with any other individual communicatively coupled to the same network. Essentially anyone with a computer, a personal data assistant, a wireless telephone, or the like can connect to the Internet and communicate with someone at a remote location within seconds. Likewise, companies can use internal networks (e.g., WANs, VPNs, or the like) to allow geographically dispersed employees to communicate in real-time using many of the same technologies. Notably, the communications can frequently occur with equipment already purchased as networks and access devices are generally already in place to handle data needs.
As this type of communications becomes more widespread, it will inevitably become a target for advertisers and telemarketers as a method to distribute advertising messages in vast quantities. Because of the low cost of distributing massive amounts of advertising, advertisers can economically transmit advertising communications with response rates that are orders of magnitude less than would be necessary to support more traditional means of advertising. Additionally, as discussed above, anonymity given the sender prevents “do not call” lists and caller-ID type mechanisms from providing an adequate solution.
Electronic mail (e-mail) has already seen this problem. E-mail is a store-and-forward communications method in which one-way communications (as opposed to a two-way communications) are sent from one network node to another network node until the final destination is reached, where a recipient may or may not retrieve a message or respond. Because e-mail is inexpensive and advertisers can transmit massive amounts of e-mail quickly (and often automatically), e-mail advertisements (e.g., junk e-mail) are becoming a burden to networks and users alike. This use of e-mail to send massive amounts of advertisements is known as the e-mail “spam” problem.
Attempts have been made to reduce the effect of e-mail spam on the end users. One such attempt is described in U.S. Pat. No. 6,052,709, wherein a system that attempts to filter incoming e-mail to identify junk e-mail is described. This system, however, only applies to e-mail, which, as described above, is a one-way communication, and does not apply to two-way, real-time communications, such as voice, video, real-time text, or the like.
Therefore, there is a need for a method and system to identify and filter unsolicited real-time, two-way communications.


The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed.
In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling down process generally provides benefits by increasing production efficiency and lowering associated costs. Such scaling-down has also significantly decreased the space separating contact openings (or windows) from adjacent devices of ICs. Contact openings provide contact between various devices and features of the integrated circuit. Due to the scaled down devices and decreased space separation between devices, it has been observed that conventional processing provides a smaller than desirable contact process window, which leads to restrictive processing and design issues. For example, the smaller contact process window results in design rules requiring a minimum spacing between the contact openings and device features (e.g., gate structures), which provides a smaller than desirable margin of contact/gate structure overlay. Further, if the minimum spacing between the contact openings and such device features varies, poor device performance results, such as contact/gate structure short and contact open issues.
Accordingly, what is needed is a method for making a semiconductor device that addresses the above stated issues.


In hierarchical computer storage systems, fast and intensively used storage are paired with arrays of slower and less frequently accessed data devices. One example of high-speed, expensive memory is a direct access storage device file buffer (DASD). Slower storage devices include tape drives and disk drive arrays, which are less expensive than a DASD.
One such hierarchical storage system is a virtual tape storage system. Such a virtual tape storage system may include, for example, one or more virtual tape servers (“VTS”) in combination with one or more data storage and retrieval systems, such as the IBM TotalStorage® 3494 Enterprise Tape Library. During operation, each virtual tape storage system is communicating data from one or more hosts, and is providing data to a second VTS for copying.
Data disaster recovery solutions include various “peer-to-peer” copy routines where data is backed-up not only remotely, but also continuously (either synchronously or asynchronously). In order to communicate duplexed data from one host processor to another host processor, or from one storage controller to another storage controller, or some combination thereof, a substantial amount of control data is required for realizing the process. A high overhead, however, can interfere with a secondary site's ability to keep up with a primary site's processing, thus threatening the ability of the secondary site to be able to recover the primary in the event a disaster occurs.
Disaster recovery protection for the typical data processing system requires that primary data stored on primary DASDs be backed-up at a secondary or remote location. The physical distance separating the primary and secondary locations can be set depending upon the level of risk acceptable to the user, and can vary from several kilometers to thousands of kilometers.
Using prior art methods, in the case where, if the peer-to-peer subsystems, i.e. both virtual tape servers, are shutdown for normal service, and for some reason only one of those virtual tape servers becomes operational, then the peer-to-peer cluster must wait until both tape servers are again operational before going online to the host computer. Therefore using these prior art methods, if a second virtual tape server fails while the first virtual tape server is shutdown for maintenance, then the entire peer-to-peer system becomes unavailable until both virtual tape servers are again operational.
What is needed is a method to distribute information about the status of a peer-to-peer data storage system across a plurality of system components such that the system itself can use that stored system information to return to operation even if all the virtual tape servers are not operational.


This disclosure is related to the field of neutron well logging measurements for determining petrophysical properties of subsurface formations traversed by a wellbore. More specifically, the disclosure relates to methods and apparatus for determining whether signals generated by a radiation detector in a well logging instrument were induced by neutrons or gamma rays. The disclosure also relates to methods and apparatus for gain stabilization of radiation detectors.
Well logging instruments known in the art include various types of radiation detectors that are capable of detecting neutrons and gamma rays. Radiation detectors include gas-filled tubes in which the gas becomes ionized following a radiation event in the tube that the detector is configured to detect. Other types of radiation detectors include scintillation detectors, which may comprise a radiation sensitive scintillation crystal optically coupled to a photomultiplier tube. Scintillation detectors may be used, for example and without limitation, detecting gamma rays so as to be able to characterize the energy of the detected gamma rays by measuring the amplitude of each signal pulse generated by the photomultiplier tube.
There remains a need for a radiation detector, or a method or system utilizing a radiation detector, that delivers improved well logging performance.


Cellular communications systems are well known in the art. In a typical cellular communications system, a geographic area is divided into a series of regions that are referred to as “cells,” and each cell is served by one or more base stations. A base station may include baseband equipment, radios and antennas that are configured to provide two-way radio frequency (“RF”) communications with mobile subscribers that are geographically positioned within the cell. A common cellular communications system network plan involves a base station serving a cell using three base station antennas, wherein each base station antenna serves a 120 degree “sector” of the cell in the azimuth plane. The base station antennas are often mounted on a tower or other raised structure, with the radiation pattern (“antenna beam”) that is generated by each base station antenna directed outwardly to serve the respective sector. Typically, a base station antenna is implemented as a phase-controlled array of radiating elements, with the radiating elements arranged in one or more vertical columns. Herein, “vertical” refers to a direction that is perpendicular relative to the plane defined by the horizon.
As demand has grown for cellular communications systems to support increased capacity and provide enhanced capabilities, a variety of new cellular services have been introduced. These new services typically operate in different frequency bands from existing services to avoid interference. When new services are introduced, the existing “legacy” services typically must be maintained to support legacy mobile devices. Thus, as new services are introduced, either new cellular base stations must be deployed or existing cellular base stations must be upgraded to support the new services in the new frequency bands. In order to reduce cost and the total number of base station antennas deployed, base station antennas are now available that include at least two different arrays of radiating elements, where each array of radiating elements supports a different type of cellular service in a different frequency band. Such antennas are typically referred to as multi-band antennas.


1. Field of the Invention
This invention relates to the recovery of proteinaceous matter from such waste protein-containing liquids as whey and tannery unhairing waste.
2. Description of the Prior Art
Precipitation of proteins from whey by heat denaturation is an old and straightforward procedure. In fact, the various whey proteins have been shown to be heat-denatured at different rates (J. Dairy Sci. 38, 351, 1955). However, the major whey proteins, .alpha.-lactalbumin and .beta.-lactoglobulin are rather resistant to denaturation by heat at the pH and concentration at which they occur in acid whey (J. Dairy Sci. 49, 694, 1966; J. Dairy Res. 37, 233, 1970). Both of these proteins are stabilized in their native conformations by internal disulfide bonds (Biochem. Biophys. Acta 200, 184, 1970; J. Dairy Sci. 57, 1152, 1974) and, at least in the case of .beta.-lactoglobulin, irreversible denaturation and the simultaneous appearance of new sulfhydryl groups has been thoroughly established (J. Dairy Sci. 33, 890, 1950; JACS 79, 126, 1957; J. Dairy Sci. 52, 585, 1969).
Tannery unhairing waste is an opaque, noxious liquid that has a 5-day biological oxygen demand (BOD) of over 19,000 ppm (JALCA 69, 50, 1974). Methods of disposing of this waste, which contains quantities of proteinaceous materials, are the subject of world wide studies (J. Water Pollut. Contr. Fed. 44, 1080, 1972; ibid 43, 998, 1971).


1. Field of the Invention
This invention relates to punch presses, and more specifically to gaging used to locate a workpiece with respect to the die and hence with respect to a previously prepared program of punch press operation.
2. Prior Art
Various types of gaging have been provided on punch presses to orient a workpiece with respect to a program of press operations. The problem is to get an exact precise dimension of predetermined size between the gaging surface and the centerline of the die. For example, at typical dimension is 48.000 inches plus or minus 0.0005 inch. Thus with such a dimension, the entire range of permissible locating errors is only one part in 48,000. During usage, wear becomes an immediate problem necessitating removal, grinding and shimming. Further, prior X-axis gaging has been so constructed as to be virtually specialized for a specific punch press construction.


This invention relates to electrical connectors and more particularly to a female blade terminal comprising a part of an electrical connector.
Electrical connectors comprising interengaging male and female terminals are well known in the art and are in wide use for establishing electrical connection between various electrical components. One popular and widely used electrical connector comprises a male blade terminal adapted to be slidably received in a cage or socket defined by a female blade terminal.
There are many design parameters that must be considered when designing a connector of the blade type. Specifically, the connector must have a simple and inexpensive design; must have a relatively small size; must provide maximum current carrying capacity; must provide a low insertion force so as to allow easy connection and disconnection of the terminal elements; must provide sufficient grasping action as between the terminal elements to preclude inadvertent separation of the elements; must provide reliable and consistent operation for sustained periods of time; and must discourage corrosion and contamination of the electrical interface provided by the connector.
Whereas a myriad of electrical connectors of the blade type have been proposed and are in common usage, none of the prior art blade type connectors totally satisfy all of the noted design parameters.


1. Field of the Invention
The present invention relates to a receiving apparatus that receives radio image signals transmitted from a body-insertable apparatus, such as a swallowable capsule endoscope, inserted into a subject body by employing plural antennas arranged outside of the subject body. More particularly, the present invention relates to the receiving apparatus that performs image processing on the received radio image signals.
2. Description of the Related Art
In recent years, a capsule endoscope having an imaging function and a radio communication function makes an appearance in a field of endoscope. The capsule endoscope is swallowed from a mouth of a patient, i.e., the subject body for an observation (examination), and is eventually discharged naturally from a living body (human body) of the patient. While the capsule endoscope is inside the subject body, i.e., during an observation period, the capsule endoscope travels through organs (through body cavity) such as a stomach and a small intestine while following peristaltic motion of the organs, and the capsule endoscope sequentially images inside the organs by using the imaging function.
Further, during the observation period, i.e., while the capsule endoscope travels through the organs, image data obtained inside the body cavity by the capsule endoscope are sequentially transmitted outside of the subject body by the radio communication function such as Bluetooth, and stored in a memory that is provided inside an external receiving apparatus. When the patient carries around the receiving apparatus that has the radio communication function and a memory function, the patient can freely move without any inconveniences even during the observation period, i.e., after swallowing the capsule endoscope until discharging the capsule endoscope. After the observation, a doctor or a nurse can display an image inside the body cavity on a display unit such as a display based on the image data stored in the memory of the receiving apparatus to make a diagnosis.
In general, the receiving apparatus includes plural antennas dispersively arranged outside of the subject body to receive image signals transmitted from the capsule endoscope, and switchably selects one antenna that has small error in receiving the image signals to receive the image signals, and performs image processing on the received image signals. In a medical apparatus proposed in Japanese Patent Application Laid-Open No. 2003-325439, a capsule ID corresponding to a unique number such as a capsule serial number is superposed on image signals of the capsule, and externally transmitted in a frame format, so that a capsule-side switch for identifier setting is not necessary and an amount of information of the identifier is reduced.


1. Field of the Invention
The present invention relates to a method for the assembly of and the interconnection by diffusion of bodies of metal alloys. More particularly the invention relates to methods of the kind comprising a sequence of activation of parts to be joined and a sequence of applying pressure when hot which gives rise to interconnection by interdiffusion of the solids.
2. Summary of the Prior Art
Metal alloys of which interconnection can be effected by these methods are alloys of the kind which are resistant to heat or to corrosion comprising, having in proportions by weight, at least 50% of a metal of the group nickel, cobalt and iron or an alloy of at least two of these metals. Certain of these alloys are designated by the term "super-alloys" and in such alloys the remainder is constituted by elements such as chromium, aluminum, molybdenum, titanium, tungsten, niobium, etc., which form a solid solution and form intermetallic compounds or alternatively form with carbon dispersed phases providing the required functional characteristics (mechanical strength and resistance to corrosion) at elevated temperatures. These alloys are used, for example, in the construction of turbo machines.
By "body", there is to be understood herein and in that which follows, simultaneously, and indifferently, either relatively large parts of predetermined shape and dimensions, for example intended to form a welded assembly, or powder grains intended for the production of parts by sintering and by compaction when hot. In practice, the interconnections, junctions or joints envisaged by the invention concern simultaneously, either two relatively large parts, or such a part and a powder, or powders, and, for the interconnection or joining of two relatively large parts, the invention is applicable whether or not an external deposit element is incorporated and which is constituted, for example, by a brazing compound. The assembly method and interconnection concerned thus encompasses different assembly and connection methods either by welding/diffusion, or by brazing/diffusion or by sintering or by compaction when hot. Briefly, the principles of these methods generally known to the man skilled in the art are will now be summarized.
The method of welding/diffusion involves welding the solid phase in which the parts are kept in contact under a given pressure and brought to a predetermined temperature, lower than the initiation of the melting temperature, over a predetermined time period. These operational conditions lead to local plastic deformations of the contact surfaces, which, in turn, give rise to an intimate contact of the latter thus rendering possible the migration of atoms between elements and/or recyrstallisations at the interface. In the ideal case, once the operation is completed no presently available technique enables the initial contact interface to be distinguished, whether this is considered from the microphotographic, chemical or mechanical aspects.
As for brazing/diffusion, it consists in the insertion between the two parts to be assembled of a thin layer (foil or powder) of an alloy particularly with a nickel base comprising additions (fluxes) such that the temperature of the liquids of the alloy will be less than the temperature of the initiation of melting of the superalloy. Heating causes initially the fusion of this layer and its connection with the superficial contact layers of the parts, then the reduction in the local proportion of the or each flux by migration into adjacent zones of the parts. In fact, it does not relate to a welding method by solids interdiffusion but the application of a known brazing technique then the diffusion of the fluxes of the brazing material in order to elevate the temperature of fusion of the connecting layer.
Sintering is likewise shown to be of interest for the production of parts of super-alloys, given the difficulties encountered during the use of conventional methods such as machining or forging. Sintering enables the production of complex shaped parts starting from a superalloy powder which, after having been shaped, is submitted to the operation of sintering itself. The latter consists either in heating the powders to a predetermined temperature after compaction when cold in a mould or matrix, or to place the powders under pressure at a predetermined temperature, lower than the temperature of commencement of melting fusion or the latter enables the production of a consolidation of the part by a phenomenon analagous to welding by diffusion at the zone of each grain. The physical and mechanical properties of the sintered parts clearly depend upon the quality of the junctions or connections formed between the powdered grains.
The assembly of the bodies can be carried out either between similar materials, or between different materials by their composition or their nature: a dense material and a powdered material for example.
The superior mechanical characteristics of the alloy used, are accompanied on the negative side by difficulties of fabrication of the parts or of the assemblies, especially by sintering or diffusion welding.
It is in practice apparent during tests of the mechanical strength of assemblies of parts of alloys welded by diffusion, and micrographic examination, that for certain grades of super-alloys or for certain special alloys of the non-oxidizing type, the connection produced after welding by diffusion is of mediocre quality; similarly the strength of sintered parts produced by super-alloys is poor, the cohesion of the assembly being less than values conventionally obtained. In certain cases no joint or connection is possible.
Observations based on electron microscope pictures, and the study of constituents by microanalysis have enabled evidence to be produced that these defects were due to the formation in the superficial contact layers of segregations or precipitates which may harm and even prevent diffusion. These segregations or precipitations result from the migration of certain constituents during the increase in temperature preceding the operation which effects the joint or connection.
This phenomenon of the formation of a barrier to diffusion is more particularly apparent for super-alloys containing, in addition to a non-negligeable amount of carbon, a relatively high quantity of titanium, for example upwards of 0.15% of carbon and 1.5% of titanium. It has been shown in this case, after diffusion welding, for example on one hand the presence in the interface of a quasi-continuous boundary formed by segregation of titanium compounds comprising especially carbon and titanium and, on the other hand, the absence of recrystallisation. FIG. 1a shows a microphotograph, obtained at an enlargement of 2500 times, at one example of an assembly of parts in which the phenomena hereinbefore noted may be observed. Mechanical tests confirm that the joint or connection thus produced is defective.
In French Patent Specification No. 2 380 354, with the object of resolving these difficulties, a preparatory treatment before the connection operation is proposed, consisting in a roughening treatment by heating in an enclosure where a hydro-halogen atmosphere is circulated composed of a mixture of hydrogen and of a hydrogen halide. French Patent Specification Nos. 1 170 557 and 1 243 415 also set out the conditions for carrying out the treatment in a fluoride atmosphere produced from chromium fluoride and ammonium fluoride in the form of a cement in the treatment enclosure obtained under a reducing atmosphere, for example of hydrogen. The use of the atmosphere of hydrogen can, however, lead to certain difficulties and constraints particularly the way of putting the technique into practice.


Prior art cardiac monitoring devices such as cardioverter defibrillators, holter monitors, or ICU monitors often use the same criteria to detect and subclassify cardiac arrhythmias. Prior art devices commonly utilize a single criterion such as cycle length to detect tachyarrhythmias. These devices generally measure cardiac cycle length by measuring the time between the large electrical deflections produced when the ventricles depolarize. The electrical deflections are sensed when the signal amplitude exceeds the amplitude of a programmed threshold. Prior art devices detect tachyarrhythmias by determining when the cardiac cycle length, or time between consecutive ventricular contractions, falls below a programmed level. The programmed levels are typically as follows: a cycle length greater than 500 milliseconds (ms) is identified as normal, a cycle length between 500 and 333 ms is classified as monomorphic tachycardia, and a cycle length less than 333 ms is identified as polymorphic tachycardia.
Thus the effectiveness of prior art devices of this type depend on the accuracy of cycle length detection. There are two major disadvantages with these devices. First, these detectors sometimes miss low amplitude electrical activity, such as during ventricular fibrillation, which can cause the detector to miss dangerous polymorphic ventricular tachycardias. Second, cycle length is not an effective discriminator between monomorphic and polymorphic arrhythmias even when the threshold detectors sense the electrical events appropriately.
Other prior art devices have been developed to overcome these disadvantages by utilizing additional parameters which can be programmed by a physician. Examples of some detection parameters include cycle length cutoff for monomorphic ventricular tachycardias, cycle length cutoff for polymorphic ventricular tachycardias, cycle length regularity, and QRS width. The disadvantage with these programmable devices is that a large number of detection parameters must be programmed by a physician. Further, this programming process can be complex, time consuming and prone to physician error.
It is highly desirable to have a non-programmable device and method for detecting tachyarrhythmias, i.e., a device which does not require programming by a physician. Further, a device is needed for use with cardioverter defibrillators, or monitors which can more accurately classify and discriminate between normal, monomorphic and polymorphic arrhythmias. Still further yet, it is desirable to have a device which can accurately sub-classify and discriminate between different types of arrhythmias within the monomorphic arrhythmia class or the polymorphic arrhythmia class. Thus, it is highly desirable to have an improved device and method which eliminates the prior art problems of missing dangerous polymorphic ventricular tachycardias when there is low electrical activity, and discriminating between monomorphic and polymorphic arrhythmias.


Conventionally, as disclosed in a patent document, Japanese Patent Laid-Open No. JP H10-19156 A (Patent document 1) listed below, a control unit performs a feedback control for controlling an electric current flowing in a solenoid of an electromagnetic valve.
The control unit described above includes: a switching section (i.e., a Pulse Width Modulation (PWM) circuit) on a power supply path toward the solenoid for flowing an electric current to the solenoid when being turned ON; a detector (i.e., an electric current detection circuit) for detecting an actual electric current value flowing in the solenoid; and a feedback controller (i.e., a microcomputer) for setting a duty ratio, which allows the detected actual electric current value to follow a target electric current value, and generating a PWM signal having the set duty ratio in a preset cycle for supplying the signal to the switching section.
The oil pressure valve, which is operated by the solenoid, is provided in the hydraulic circuit of the automatic transmission. Therefore, the control unit disclosed in the patent document 1 is used for the control of the automatic transmission. In recent years, the hydraulic circuit has a complicated structure, and a configuration of such structure includes two or more hydraulic valves in the oil circulation portion of the circuit, among which one or more hydraulic valves may be operated by the solenoid.
In such a configuration, a coupled oscillation may occur, which results from an oil pressure effect bouncing around between the multiple hydraulic valves. The coupled oscillation in such a configuration/structure is confirmed by the inventor of the present application. The mechanism of how coupled oscillation occurs in the hydraulic circuit is understood as follows.
The propagation rate of oil pressure affects the characteristic of the coupled oscillation such as frequency, amplitude and the like. The propagation rate is determined by the viscosity of the oil, and the viscosity of the oil changes according to the oxidization of the oil and the environmental temperature of the oil in which the oil is used. Therefore, when the viscosity of the oil changes according to the change of the environmental temperature of the oil, for example, the oscillation of the oil in the circuit may become noticeable (i.e., the oscillation exceeding an allowable level has occurred), thereby coupling the oscillation of many parts of the oil and the circuit to result in the coupled oscillation.
For example, when the hydraulic circuit has three hydraulic valves in the circulation portion, an influence of the operation of the first oil pressure valve is transmitted to the second oil pressure valve through the oil. Therefore, an input pressure of the second oil pressure valve is not stabilized, and a valve position of the second oil pressure valve is not converged (i.e., is not stabilized). Further, an influence of the operation of the second oil pressure valve is transmitted to the third oil pressure valve through the oil. Therefore, an input pressure of the third oil pressure valve is not stabilized, and a valve position of the third oil pressure valve is also not converged. Furthermore, an influence of the operation of the third oil pressure valve is transmitted to the first oil pressure valve through the oil. Therefore, an input pressure of the first oil pressure valve is not stabilized, and a valve position of the first oil pressure valve is not converged.
Thus, the coupled oscillation occurs from the coupling of the effects from each of the hydraulic valves, which is understood as causing a continuous operation of the same valve. That is, as the convergence of the valve position of each of the hydraulic valves stays unachieved for a long time (i.e., the continuous operation of the valve lingers on), and the oil pressure does not really attenuate, causing a continuation of the oscillation of the oil. In such a situation, the controllability of the automatic transmission may deteriorate.


DE application 10222192 describes pentafluorosulfanylbenzoylguanidines as NHE1 inhibitors. The processes described therein for preparing these compounds, however, result in low yield and require reagents and reaction-conditions that necessitate great technical complexity or are unsuitable for preparation on a relatively large scale. It has now been found that said disadvantages can be avoided by a novel efficient synthesis which starts from commercially available 4-nitrophenylsulfur pentafluoride.


A programmable device (e.g., a programmable microcontroller) contains configuration registers which hold configuration data to establish functional blocks (e.g., which perform user-defined logic functions), I/O blocks (e.g., which configures input/output blocks interfacing to external devices), and/or signal routing resources (e.g., which connect the functional blocks to each other and/or the I/O blocks).
The configuration data may be represented as configuration bits of configuration registers (e.g., stored as volatile memory). Upon the boot-up of the programmable device, the configuration data stored in non-volatile memory may be copied to the configuration registers of the volatile memory. However, the configuration data residing in the configuration registers may be compromised due to several factors.
For example, an unintended software execution may create a write-over condition where improper data may be written to the configuration registers. Additionally, cosmic rays, X-rays, and/or other environmental factors may cause the configuration data to degrade (e.g., flip); these are known as soft errors. These errors (e.g., the write-over, soft errors, etc.) of the configuration data may compromise the functional block, the I/O blocks, and/or the routing resources, thereby rendering the programmable device inoperable for its intended purposes.
In case when the programmable device is used in a critical condition (e.g., involving an emergency situation) or life critical function, the reliability of the programmable device becomes ever more critical. For instance, the functionality of an airbag deployment system may rely on the operation of a programmable device. Furthermore, the configuration data (e.g., bits) become more susceptible to the soft errors as the feature size (e.g., a silicon geometry) of the programmable device gets smaller.


1. Field of the Invention
The present invention relates to a data recording apparatus for recording data on a record (recording, recordable or recorded) medium, a method therefor, a data reproducing apparatus for reproducing data recorded on a record medium, a method therefor and a record medium on which data has been recorded. More particularly, the present invention relates to an information providing/collecting apparatus for providing and collecting so-called multimedia information, such as video information and music information, or program information and a method therefor.
2. Related Background Art
As a data record medium on which information signals, such as Audio data, video data and various data items, are recorded, means for optically recording information signals, specifically, a so-called compact disk (CD) for use in the music field and a CD-ROM which meets the CD standard and which is used for data have been used all over the world in recent years.
Hitherto, information providing service has been realized as a so-called data base system and a personal computer communication system in each of which a user terminal (a terminal of an information collecting side) and an information provider are connected to each other through, for example, the telephone line to enable information required by the user to be taken out. Another information providing service has been realized with which a large-capacity medium, such as a so-called CD-ROM having encoded information recorded thereon is distributed and key information for decoding encoded information is transmitted to the user by, for example, communication so that encoded information recorded on the CD-ROM is decoded and decoded information is copied on a hard disk or the like so as to be used.
Moreover, a technique has been disclosed in Japanese Patent Publication No. 2-60007 in which a password formed by encoding a file key by using a code key is supplied to a computer; and a program written on the record medium is decoded by a coding mechanism to prevent copying and sharing of the software program.
Hitherto, all of information items recorded on the foregoing CD or the CD-ROM are read by a reproducing apparatus and copied onto, for example, a hard disk. Then, data copied onto the hard disk is supplied to an encoder system for the CD or the CD-ROM to newly make a CD or a CD-ROM so that a pirate edition is easily manufactured. As described above, the security function, such as the copy protection, has been unsatisfactory.
The foregoing problem is also critical for a so-called digital video disk (DVD), which is expected to be a data record medium for a next generation.
On the other hand, in the conventional information providing service, a method has been employed in which key information for decoding is transmitted to a user in such a manner that key information is transmitted by means of voice through a telephone line. Thus, key information has not been encoded particularly. However, the foregoing method has a risk in view of keeping security.
In the case where communication is employed to transmit key information, one-to-one connection is usually established. Therefore, there is substantially no risk of key information being stolen. However, in the case where key information is transmitted through a network, there arises a problem in protecting key information.
Therefore, in an information providing system, in which mediums, on each of which encoded information has been recorded in a large quantity, are distributed by the information provider; and only in a case where a user requires information to obtain from the medium, key information for decoding the code is supplied and accounting is performed, the problem in view of security when key information is transmitted results in a risk to arise in that key information can be obtained by a person except the subject user. In the foregoing case, the information providing system cannot be held. If whether or not the user is a formal user cannot be specified, there is a risk that account is put down to'another person. Also in the foregoing case, the information providing system cannot be held.
Thus, security improvement in transmitting key information from an information provider to a user and reliable specification of a user are important requirements.


1. Field of the Invention
The invention relates to the protection of integrated circuits from electrostatic discharge (ESD), and more particularly to the protection of NMOS transistors by an embedded parasitic silicon controlled rectifier (SCR) which triggers at a very low voltage.
2. Description of the Related Art
The protection of integrated circuits from electrostatic discharge (ESD) is a subject which has received a lot of attention from circuit designers because of the serious damage that ESD can wreak as device dimensions are reduced. Workers in the field and inventors have proposed many solutions, many trying to solve the problem of protecting sub-micron (1 micron=10xe2x88x926 meter) devices while still allowing them to function unencumbered and without undue, or zero, increase of silicon real estate. The main thrust of ESD protection for MOS devices is focused on the use of parasitic npn and pnp bipolar transistors, which together form a silicon controlled rectifier (SCR). Unwanted as this SCR normally is, it can safely discharge dangerous ESD voltages as long as its trigger voltage is low enough to prevent gate oxide breakdown of the MOS devices of which it is a part.
Among ESD protection devices SCR protection shows good clamping capability (a very low holding voltage) compared to Gated-NMOS, however, a larger trigger voltage and latch-up concerns are always the drawbacks. See below a discussion of the graph of FIG. 1. In the sub-micron technologies, the Gated-NMOS is mostly used for a robust ESD design. A problem exists for the 0.15 micron process because the Gated-NMOS snapback voltage (larger than 5 volt) is higher than the gate oxide breakdown of 10 Million volt/cm. For 0.6 and 0.5 micron high voltage technology, the Gated-NMOS will generally show its weakness on high voltage (12 volt, 40 volt) ESD due to higher drain junction breakdown and higher snapback voltage.
The following publications describe low voltage lateral SCR structures to protect the input and output circuitry of an integrated circuit during an ESD event:
xe2x80x9cA Low-Voltage Triggering SCR for On-Chip ESD Protection at Output and Input Pads,xe2x80x9d A. Chatterjee and T. Polgreen, IEEE Electron Device Letters, Vol. 12, No. 1, Jan., 1991.
xe2x80x9cLateral SCR Devices with Low-Voltage High-Current Triggering Characteristics for Output ESD Protection in Submicron CMOS Technology,xe2x80x9d Ker, IEEE Transactions On Electron Devices, Vol.45, No.4, April 1998, pp.849-860.
FIG. 1 is a graph of the I-V characteristics of a 0.15 micron process SCR/Gated-NMOS device. Curve 1 (dotted line) shows the characteristics for the SCR and Curve 2 (solid line) shows the characteristics for the Gated-NMOS. It is obvious that the SCR has the lower holding voltage while the Gated-NMOS has the lower trigger voltage. Another drawback of the SCR""s is the latch-up concern.
We now describe in FIG. 2 a prior art low-trigger SCR for on chip ESD (IEEE, Electron Device Letters, Vol. 12, No. 1, January, 1991, see reference above). In a substrate 21 is embedded an n-well 32. Also implanted in substrate 21 is gated NMOS T1, comprising n+ drain 22, gate 23, and n+ source 24. Implanted next to n+ source 24 is p+ diffusion 25. Implants 23, 24 and 25 are tied to a voltage reference 39 (typically ground). N+ drain 22 is connected to chip pad 38. Implanted in the n-well are n+ diffusion 26 and p+ diffusion 27 which also are connected to chip pad 38. Halfway straddling the n-well is n+ diffusion 28 which is the drain of gated NMOS T2. T2 further comprises gate 29 and n+ diffusion (source) 30. A p+ diffusion 31 is implanted next to n+ diffusion 30. 29, 30, and 31 are connected to 39. Therefore, both T1 and T2 are grounded gate NMOS transistors. 26, 27, 28, 30, 31, and 32 make up the external SCR (external because the SCR is largely external to the gated NMOS transistors T1, T3, and T4). The latter two transistors are not further described since they follow the pattern of T1. The SCR itself comprises a parasitic bipolar pnp transistor Q1 and a parasitic bipolar npn transistor Q2. Drawbacks of this layout are a) the external SCR and b) low current capacity resulting in poor protection efficiency.
FIG. 3 is a schematic diagram of the layout of FIG. 2 where the same numbers indicates the same items.
Another prior art lateral low-voltage, high-current SCR (IEEE Transactions On Electron Devices, Vol.45, No.4, April 1998, see reference above) is shown in FIG. 4 which is described in the cited IEEE document on page 851. Drawbacks of this design are:
a) poor I/O and VDD/GND connections causing latch-up concerns,
b) the SCR is still outside of the main protection area leading to poor efficiency. Latchup occurred, see Arrow A, at a voltage difference of larger than 0.7 volt caused by diode Dp2 because of P-N diode forward cut-in.
Other related art is described in the following U.S. Patents:
U.S. Pat. No. 5,872,379 (Lee) describes a low voltage turn-on SCR to provide protection to the input and output circuitry of an integrated circuit during an ESD event.
U.S. Pat. No. 5,907,462 (Chatterjee et. al) teaches a gate coupled SCR, where the stress voltage is coupled from a pad to a gate electrode causing a NMOS transistor to conduct, thus triggering the SCR.
U.S. Pat. No. 5,939,756 (Lee) discloses an added P-well implantation for uniform current distribution during an ESD event to provide improved protection to the input and output circuitry of an integrated circuit.
It should be noted that none of the above-cited examples of the related art show part of the drain and the p+ diffusion in the n-well, nor having the drain connection tightly tied together at the p+ diffusion and the n+ drain as in the presently disclosed invention.
It is an object of the present invention to provide circuits and methods for an embedded SCR implemented in either 5 volt or 12 volt I/O devices.
Another object of the present invention is to provide for an embedded SCR which operates at less than or equal to 2 volts to prevent gate oxide damage, particularly in 0.15 micron 5 volt technology.
A further object of the present invention is to provide for an embedded SCR where the ESD pass voltage of 8,000 volt is achieved for the 12 volt process.
Yet another object of the present invention is to provide a latch-up free SCR.
These objects have been achieved by inserting the p+ diffusion and the n-well in the drain side and a part of the drain to form a low-trigger, high efficiency SCR. Further, the layout is such that the drain connection is tightly tied together at the p+ diffusion and the n+ drain making that connection very short and thereby preventing latch-up. The parasitic SCR is made more efficient because it is entirely within the n+ diffusions (the source of the grounded gate NMOS transistor) at either side of the structure and, thus, called an embedded SCR. For the 12 volt I/O device the design is modified by placing each of two n+ drains in its own n-type doped drain (ndd) area and straddling halfway the n-well. The structure is repeated as required and a p+ diffusion is implanted at both perimeters and connected to the nearest n+ source and a reference voltage.