Damsterplein Groningen Netherlands
During Eurosonic 2016 Wednesday to Friday.

To be as fuel efficient as possible

Most outdoor events consume a huge amount of diesel and often this is unnecessary. How can festivals optimize their energy provisioning in order to save diesel and the environment in 2016?

Powerfest is a collaborative between different companies in the event industry. During Eurosonic we aim to be as fuel efficient as possible and inspire festival organizers to improve their energy consumption.

Matching supply and demand

First of all we need to know what kind of equipment is used. The more details we have the better we can match the supply and demand.

Efficient energy provisioning

Secondly we need the most efficient energy supply. The generators on the Damsterplein are equipped with smart power management, always running on the highest efficiency.

Finally it is crucial to know how the energy demand has been during the event. By monitoring and visualizing the energy demand we can come up with more efficient solutions, saving up to 40% on diesel consumption during upcoming editions.

Innofest & Eurosonic

A festival is a temporary city. And because it is rebuild every year it offers the opportunity to experiment with new technologies. Additionally festivals bring people with different backgrounds together, making it the perfect place for collaborations and the sharing of knowledge. The project Innofest – Festival Driven Innovation offers a variety of festivals within the north of The Netherlands to test, develop and present innovative technologies.

Eurosonic acknowledges the importance of stimulating innovation. Within that perspective they co-initiated Innofest and the Powerfest project during Eurosonic 2016.

Powerfest is brought to you by:


Format: Paperback

Language: English

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Downloadable formats: PDF

Our museum replicas of unsurpassed quality and lasting beauty have already become centerpiece of many home, office and garden collections. This was a time when several different kings ruled different parts of Egypt. Traces the development of Egyptology and includes interviews with Egyptologists and archaeologists currently working in Egypt. 1971. 52 min. Spanish words that begin with "al" are always suspicious, but in this case the word in Arabic begins with a "sun letter" ("t."), which means that it assimilates the pronunciation of the "l".

Pages: 64

Publisher: Shire Publications (March 4, 2008)

ISBN: 0852637888

Tutankhamen's Curse: The Developing History of an Egyptian King

The original NASA photo may also be viewed here. Images pointing to the Egyptian Ankh relic in the Curiosity rover photo were uploaded to YouTube on Jan. 14 online. Many of these are based on the analysis of individual cuneiform tablets. Only in recent years has a significant number of synthesizing monographs and collective works begun to appear. The limitations of Assyriology as a field, and hence of our knowledge of ancient Mesopotamian civilization, have been considered by Oppenheim (1964). This theme has been taken up by Bottero (1992), although in my opinion more ethnocentrically, and hence less successfully, than by Oppenheim A Journey Through Ancient Egypt. Being settled in one place made it possible to domesticate animals in order to provide other sources of food and clothing Egyptian Gods and Myths (Shire Egyptology) online. Ramses III constructed the enormous palace temple of Medinet Hebu but the empire had begun to disintegrate with strikes, assassination attempts and provincial unrest. His successors, who were all named Ramses, presided over the decline of their empire until Ramses XI withdrew from active control over his kingdom, delegating authority over Upper Egypt to his high priest of Amun, Herihor, and of Lower Egypt to his minister Smendes Song of Armageddon. She built a splendid temple dedicated to him and to her own funerary cult at Dayr al Bahri in western Thebes. One of the greatest temples still standing is that of Pharaoh Amenophis III at Thebes. With Amenophis III, statuary on an enormous scale makes its appearance. The most notable is the pair of colossi, the so-called Colossi of Memnon, which still dominate the Theban plain before the vanished portal of his funerary temple An Egyptian Princess : Volume VI (Illustrated). Their attire is solely for their royal status, copied from the Anunnaki whom they saw as the pinnacles of status Herodotus. Chinese accomplishments During the Zhou and Shang periods, the Chinese made remarkable achievements in astronomy and bronzework, learned to make silk and create books, and developed a complex system of writing E:Chinese invented silk Silk was exotic and expensive, so it was good for trading with the rest of the world Egypt Under the Pharaohs: A History Derived Entirely from the Monuments V2 1891.

Download Egyptian Gods and Myths (Shire Egyptology) pdf

The Nile water, rich silt, and semi-troical climate resulted in highly productive harvests that served as the basis for Egyptian civilization over several millenia. The average Egyptian lived and worked in his village and knew little of the wider world pdf. The leaders of Upper Egypt wore the white crown and took the sedge as their emblem. After the unification of the two kingdoms, the pharaoh wore the double crown symbolizing the unity of the two lands An Egyptian reading book for beginners. They say, “It took over 20 years to build the pyramids” and “ they were made of over 2 million blocks.” Houses were made of bricks and mud as glue download. In modern Egypt ‘It is a race against time to document, publish and conserve the inscribed wall surfaces of some of the most famous monuments of the ancient world. With the rising water table, increased pollution, urban expansion and agricultural encroachment threatening these priceless vestiges of Egypt’s past’ The Egyptian Pyramid Mystery Is Solved!: Volume 1: The Mysteries. The last type of physician called the magician-physician, was not trained in medicine and only used spells to cure the ill. This signifies that although the Egyptians made advances in the field of medicine, the aspect of magic never their medicine. All physicians of Egypt were regarded in high favor of the kings. They were given such titles as “Chief of all court physicians” The nobles also used the term “body physicians.” These “body physicians,” were permanently employed The Nocturnal Magic of the Pyramids.

The Jesus Legacy

Even in the New Kingdom the only opportunities offring advancement outside of the laboring caste was the army. [Aldred, p. 23.] Egyptian peasants were iliterate and attended no schools. The younger children were assigned tasks such as protecting the crop from birds or gleaning the stubble aftr harvest. Some Egyptians owned their own land, many toiled as tennants on the estates of the great temples or nobility Ancient Egypt: The Basics. Using 3 identical organizers for each topic, each student will write a 5-paragraph essay comparing the contrasting ancient Egyptian and modern civilization, using three aspects that mostinterested him/her. Students will peer-edit their paragraphs Cleopatra to Christ: Jesus: the great-grandson of Cleopatra. (King Jesus Trilogy) (Volume 1). They were originally covered in limestone and topped with gold. The tallest, the Great Pyramid, is 482 ft (147 m) high. A mummy is a dead body that has been carefully preserved, or mummified. Workers removed organs that might rot, then dried the body with natron (salty crystals) and wrapped it in resin-soaked bandages. Ancient Egyptians thought that people were made up of five elements An Oasis City (Institute for the Study of the Ancient World). Until recently, the history of those cultures has been largely ignored by modern civilization. Harder - Africa has been called the "birthplace of the human race." The oldest evidence of human-like creatures and people found anywhere in the world are the bones and other fossils discovered at many sites in eastern and southern Africa Die datierten und datierbaren Ostraka, Papyri und Graffiti von Deir el-Medineh (Agyptologische Abhandlungen). Their belief in the rebirth after death became their driving force behind their funeral practices. When a person died, the priests recited prayers and a final attempt was made to revive the deceased The Bishops of Faras: An Anthropological-Medical Study. The Sumerians contributed to the development of metalworking, wheeled carts, and potter's wheels. They may have invented the first form of writing. They engraved pictures on clay tablets in a form of writing known as cuneiform (wedge-shaped) Egypt from Alexander to the Early Christians: An Archaeological and Historical Guide.

Religion of the Ancient Egyptians

The Egyptian Book of Days: The Calendar of Ancient Egypt

Hieroglyphics: The Writings of Ancient Egypt

The Life and Times of Joseph in the Light of Egyptian Lore (Classic Reprint)

The Ancient Engineers

The Hyksos: The History of the Foreign Invaders Who Conquered Ancient Egypt and Established the Fifteenth Dynasty

Slab Stelae of the Giza Necropolis (Publications of the Pennsylvania-Yale Expedition to Egypt)

Sunken Cities: Egypt's Lost Worlds

In Search of the Woman Pharaoh Hatshepsut

Transactions of the Royal Historical Society, Volume 4

The Cat of Bubastes [Epic Audio Collection]

Ramesside Inscriptions, Translations: Merenptah and the Late Nineteenth Dynasty

The Tomb of Nyhetep-Ptah at Giza and the Tomb of Ankhmahor at Saqqara (University of California Publications : Occasional Papers ; No. 11)

Reflections of Osiris: Lives from Ancient Egypt

New Classical Fragments and Other Greek and Latin Papyri (Classic Reprint)

ATLANTIS:Encrypted Of The Missing Links For Today`s Survival.: By: Dr. Malachi K.York

Tutankhamen: Amenism, Atenism and Egyptian Montheism, With Hieroglyphic Texts of Hymns to Amen and Aten

Yet, even if Eyre (1987a:38) is correct that ancient Egyptians believed that vertical mobility was right, both up and down the social ladder, this was almost certainly an ideal that was realized only to a very limited degree, if at all, in the lives of most Egyptians Cleopatra: (Spanish Edition). T-shaped or L-shaped with a raised end bar, these shadow clocks measured the morning hours as the sun swept overhead. Then, they were turned around to count down the afternoon. It's important to keep in mind that the Egyptians weren't developing methods for timekeeping in a void. The practice of studying the passage of time -- whether minutes, hours, days, seasons, years or much longer -- was a passion of several ancient civilizations Egypt The World of the Pharaohs. C (300-400 years before the people of Kemet, Egypt began the Pyramid of Djoser). These cities flourished peacefully for more than 1,200 years. Something very different from all other civilizations is that this people lived without fears, in peace. No traces of warfare have been found, a finding that had to make archaeologists in the world to re-invent their thinking and theories about why tribal people built and moved into large cities download Egyptian Gods and Myths (Shire Egyptology) pdf. The vessels which crossed the Atlantic about 1500 B. C. (during the early Afro-Olmec period) were most likely the same types of ships shown in the sahara cave paintings of ships dating to about 7,000 B A Palaeographic Study of Early Writing in Egypt (Orientalia Lovaniensia Analecta). During Peret, the growing season, which lasted October-February, farmers tended their fields. Shemu was the season of harvest and abundance. They would either carry water by hand, by camel, or would dig irrigation canals from the Nile River to water the rich black kemet of the fields. Farmers cultivated all manner of crops: barely for beer, cotton for clothing, melons and pomegranates and figs for an evening meal Ancient Egyptian religion (Harper torchbooks: The Cloister library). Yet, the ancient Egyptian religion has never really completely died out. Even today, many Egyptians continue customs, including some aspects of religion, held over from thousands of years ago epub. If Afrocentrists upset you, then Eurocentrists should as well, and maybe even more, as their views have dominated the history books and popular culture (in film, the ancient Jews, Egyptians and even some Chinese and Japanese characters have been played by European actors�.and they always, always have British accents) The Laws of Moses and the Code O Hammurabi (Classic Reprint). In 332BC Egypt was invaded by Alexander the Great and was then ruled by Greek Kings. I will never give away, trade or sell your email address. My name is Mai and I’m the founder of EAE, an online platform dedicated to bringing you the magic and wonders of Ancient Egypt right to your screen. I am currently updating and rebranding the entire website so you won’t find all the old content right now Howard Carter and the Discovery of the Tomb of Tutankhamun (Guides). Egyptian life depended on what social class you were a part of Egyptian Women of the Old Kingdom and of the Heracleopalitan Period. In Frank's class, it is a symbol for archaeology itself because it unlocked the ancient Egyptian past. Big reason for the loss and destruction of societal history and culture throughout the world. A city state of the mayan empire located on the border of Honduras ruled by Yax Pahsaj who created many monuments to show his relationship to the 15 kings that preceded him. "the Boy King" Serving as the pharaoh of Egypt as a child from 1334 bc to 1325 bc HUMANITY: ITS FOUNTAIN AND STREAM.


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The president of Bashkortostan visited JSC "Gas-service"

On November 2, the President of Bashkortostan Rustem Khamitov visited JSC "Gas-service". The head of the republic examined the company shops, the central warehouse, the central emergency dispatching service, estimated construction of a gas distribution station. Also he had a conversation with the company collective and visited a museum of the enterprise history.

Rustem Khamitov showed an interest in new technologies which are used in JSC "Gas-service". The geo-information system is introduced at the enterprise, allowing to carry out dimensional analysis and modelling of engineering networks, to carry out hydraulic calculation of any site. Telemetry technologies are successfully being implemented enabling to operate gas supply processes.

18 central emergency dispatching services and 65 branches of emergency services work in the gas system. JSC "Gas-service" branches annually spend trainings of controls and emergency-dispatching services, localisation of failures where also other engineering services from republican cities and areas participate. The enterprise actively solves the task on transition to complete gasification of the region.

According to the President of Bashkortostan, JSC "Gas-service" has good base and prospects for development.

Яндекс цитирования
Рейтинг ресурсов "УралWeb" -->


Women and Feminism in Sir Thomas More's Utopia

First published in 1516, Sir Thomas More's Utopia is considered as one of the most influential works of Western humanism. Through the first-person narrative of Raphael Hythloday, More's mysterious traveler, Utopia is described as a pagan communist city-state or polis governed by intellect and rationality. By addressing such issues as religious pluralism, women's rights, state-sponsored education, colonialism and justified warfare, the main protagonist seems to be a very recognizable character to many contemporary readers even after more than five centuries while Utopia itself remains a foundational text in human philosophy and political ideology through the world.

In his description of the religious practices held within More's perfectly structured Utopia, Raphael Hythloday informs the reader that "Women are not debarred from the priesthood, but only a widow of advanced years is ever chosen, and it doesn't happen often" (Utopia 78). Examples of this rather discriminatory, symbolic remark can be found throughout the text of Utopia which is embedded with many inconsistencies and conflicts related to philosophy. At the conclusion of Utopia when Hythloday has terminated his extremely detailed narrative...

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Explore Scientific TDM Version 2.5
Explore Scientific TDM Version 2.5
DKK 7.699,00

Explore Scientific TDM Version 2.5

Telescope Drive Master (TDM) er udviklet til at kompensere for periodiske og ikke-periodiske tracking fejl på masseproduceret ækvatorial monteringer, hvis tracking fejl stammer fra mekaniske og monterings unøjagtigheder.

Produkt beskrivelse:
Sættet består af følgende dele: 1 stk. høj præcision rotary encoder som monteres direkte på RA aksen uden kobling eller gear, samt en elektronisk kontrol boks. Bemærk venligst at der ikke medfølger adapter til montering - købes separat.

The electronic controller unit compares the signals incoming from the high precision rotary encoder mounted onto the RA shaft with time signal of the internal quartz oscillator. If the angular velocity of the RA shaft deviates from the prescribed (sidereal or
average King-rate) velocity value, it accelerates or delays telescope’s driving clock. In this way, a high precision, feedback regulated, real-time rotational speed control has been created. Corrective action happens via auto-guider input port of telescope’s driver unit of its own.

Advantages of using TDM:

- Eliminates telescope mounts’ tracking error down to negligibly small values. The followed object (without large scale proper motion) deviates from its theoretical position on the CCD surface in smaller degree than ±0.5” (or less than 1” p-v amplitude) during 5-10 minutes long observation more than in 95% of duration of total exposure time. (The data above depends on the object position observed in the sky, type of certain mount and accuracy of its polar alignment.)

- It is not necessary to install auto-guider telescope or to use guider chip/camera.

- It does not need to find bright guide star for tracking (the observation process can be automated on much easier way).

- TDM can speed up the high volume observation work on remarkable way since exposition can be started immediately after the scope turned onto its target (and potential RA-gear backlash worked off).

- TDM is very easy to use due to its self-test functions.

- TDM compensates each element of tracking errors coming from the whole RA drive chain (between motor shaft and RA shaft) since the rotational sensor has been mounted onto the RA shaft directly. It means that TDM inspects very slow rotation of RA shaft continuously in real-time and will correct it immediately if it is necessary.

- TDM is a standalone application so it does not need any PC support or other external device for using it.

- Thanks for the built in, high stability and high precision quartz-oscillator based clock-signal the tracking accuracy of the telescope’s drive system is not a relevant parameter.

- The electronic module of TDM can be used for other mounts as well so you need to change the mechanical adaptor only if you have several mounts or want to change the type of your permanent mount.

- It is possible to create a high precision periodic error (PE) curve of your mount using the serial (USART) port of TDM connected to your PC in your room without “in-situ” test under the night sky. You just need to download and use the software (TDM Monitor.exe) from the companion CD.

TDM has been developed as “easy-to-use” device, so you can subsequently attach its mechanical adopter onto the RA shaft of most popular mass-produced telescope mechanics easily, without disassembling mount. This is a “Plug-and-Play” device so you do not need any special mechanical or electronic study or background to install and use it.

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Galilean Nights in Argentina

Longtime S&T reader, amateur astronomer, and science journalist Mariano Ribas writes from Buenos Aires, Argentina:

Mariano Ribas
The first Galilean Night (Thursday, Oct. 22) was a total success at the planetarium in Buenos Aires. Five hundred people gathered here to look at the Moon and Jupiter with our two biggest scopes (11- and 12-inch SCTs, and to learn something about Galileo´s life and contributions to the modern astronomy. Half of them had never seen the sky with a big telescope, including more than 100 children, who observed the Moon and Jupiter shouting "Wow," "Wonderful," "Incredible"!

On Friday it was cloudy. But our second Galilean Night, on Saturday, was even better, with 700 visitors.

For us these Galilean Nights are very, very special, because our planetarium´s name is... Galileo Galilei!

One thought on “Galilean Nights in Argentina

  1. Graham Wolf

    Well done Argentina! Here in New Zealand’s Capital City (Wellington) we had similar sucess right in the CBD… it’s all about taking astronomy to the streets!

    Here in Wellington on the 24th, from 7pm -11:30pm; countless folk walked past, or stopped their cars on the main street, got out, walk over and view both the Moon and Jupiter through am “armada” of locally owned telescopes, for NO COST! What a great way to honour Galileo, what a great freebie for the Kiwi public (and a few dozen tourists included). Astronomy crosses so many cultural barriers… astronomers (professional AND amateur) just love sharing their passion for the night sky.

    Galileo would have been proud to learn that worldwide, there are countless astrronomers-of-the-future inspired by such public events, eager to take up the “torch”, and further his immortal work. After 400 long years, Astronomy’s “founding ancestor” is being appropriately commemorated via IYA. Astronomy continues (through international collaborations) to bring humankind closer together, unite nations and cultures. Let’s have more such united international events!

    Graham Wolf (New Zealand)


Cassandra and Alex

My blogs

Blogs I follow

About me

Occupation Corporate drones
Location Madison, WI, United States
Introduction Cassandra and Alex met at work - where they slaved away together for 13 years (until Alex abandoned Cassandra for a new company). Cassandra likes to say that they were like "an old pair of shoes" - they just fit. As a designer and writer respectively, they have naturally dove-tailing creative abilities. However, their shared inability to focus does, occasionally, make it tough to get anything done efficiently.
Interests knitting, cooking, reading, sewing, building stuff, making things pretty, making things sound good, movies, gardening, kids (Cassandra), dogs (Alex), anything shiny


Pinterest • The world’s catalogue of ideas

READ - Muslim Brotherhood Launches Political Network to Promote Sharia Law in the US. How can we be okay with this?!?!

Republican Slugfest - "Last week’s NY Times article highlighting Republican’s continued efforts to mount legal challenges to the new healthcare law are embarrassing me as a Republican-leaning independent. For one, this ship has sailed. The opposition may have future victories in court but they’ll be minor in comparison to the Supreme Court’s decision to uphold the Act. The Affordable Care Act, for all its failings and incompetent rollout is the new norm – whether you like it (50% of…

Angela Davis, looking fierce and beautiful. What Emmy Hughes's mom might look like: from The Last King, a fantasy/romance novel by A. Yamina Collins

The Democrat party was the first political party in the US & they owned slaves & made so much profit from slavery that they fought tooth & nail to keep slavery legal. The Republican party was started to END SLAVERY & the Democratic party continued to put

Well I do prefer my wine red and my mountains white (politically libertaRian), love blue skies! Especially in the fall contrasted with a New England fall

Why don't people understand this? It's old news, something I learned in school when a kid. What the hell are schools teaching that they don't have time for Phys Ed etc, but they also don't teach REAL history or read classics or how to think and gain a foundation to succeed in life, either? Is a school day focused solely on liberal, socialist indoctrination? What ARE they doing all day?!

Wanted poster for Angela Davis, 1970. Angela Davis (born January 26, 1944) is an American political activist, scholar, and author. Davis emerged as a nationally prominent activist in the 1960s, when she was associated with the Communist Party USA, the Black Panther Party. She is a retired professor with the History of Consciousness Department at the University of California, Santa Cruz and is the former director of the university’s Feminist Studies department.

Washington, D.C.

REJECT THE #NULL:There R not 2major political parties in USA;there is only 1 #TyrantClass pretending2B 2major parties


Problem Statement:
Demonstrate the usage of threading in python.

Let’s consider an example where we have two scripts, one of them is the “main.py” script that can be considered as parent and the other that would run in threads “log.py”.

Let’s first take a look at
import time

class log:
def __init__(self, times):
self.times = times
self._bOn = True

def start(self):
while (self._bOn):
print “in start”

def stop(self):
self._bOn = False
print “in stop”

log.py contains a class log with constructor that takes argument for time and sets the bOn variable to True.
start() – starts printing “in start” till the time bOn is True.
stop() – prints “in stop” when it is called. It would also stop the start() function as bOn is set to False now.

Now on to the parent script that would call log.py to run in thread.
import os
import log
import time
import thread

obj = log.log(5)

def startlog():
print “in thread”

Main.py, imports log.py with constructor argument as “5”.
startlog() – prints “in thread” and then would call start() of log.py
startlog() is now run as a thread
Main script sleeps for 11 seconds and then
calls the stop() of log.py

In this example, when Main.py starts running, it imports log.py and sets the argument(time) of the constructor to 5. It then starts a thread for the function startlog() and goes to sleep for 11 seconds.
Now that a thread has started with startlog() function, it prints “in thread”, then calls start() of log.py. Now that bOn is True, it prints “in start” and sleeps for 5 seconds as set by Main.py. After 5 seonds again it prints “in start”.
During this time the Main.py is still sleeping. When 11 seconds pass by, Main.py comes out of sleep (log.py is still running though) and calls the stop() of log.py. Because of which, start() gets stopped as bOn is now set to False and it prints “in stop”.
Thus we have seen, Main.py and log.py both ran in parallel and Main.py could control the execution of log.py as it was run in thread.


Marshmallow Hydroglyceric Extract

EPO S.r.l.

Marshmallow Hydroglyceric Extract (CAS 73049-65-7) is a brown to yellow opalescent liquid that is produced from the roots of Althaea officinalis L. which belongs to the botanical family Malvaceae. This product contains active ingredients such as mucilages, tannins, and flavonoids. It can be used as an additive in the food industry due to its ability to improve the functionality of the mucous membranes of the respiratory tract and regulate functionality of the digestive system.

产品技术规格书 TDS

EPO S.r.l.


Terminology related to nuts and bolts

Presented below is a glossary of terminology on topics related to nuts and bolts, threaded fasteners and tightening techniques. If you have any questions about any of the content or you think we've missed something why not send us an Email on the topic.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

We have a web site dedicated to training, have a look at - for additional information on bolting technology.
Acorn Nut
A nut (so-called because of its shape) that has a domed top so that it prevents contact with the external thread.
A torque prevailing nut of all metal construction. The nut is slotted in two places which, after the nut has been tapped, are bent slightly inwards and downwards. When the nut is screwed onto the bolt thread the two slotted parts are forced back to their original position. Their stiffness causes the nut threads to bind onto the bolt threads and thus provides a prevailing torque. Aerotight is a registered trade mark of The Premier Screw and Repitition Co. Ltd of Woodgate, Leicester, United Kingdom, LE3 5GJ.
AF coatings are dry lubricants consisting of suspensions of solid lubricants, such as graphite, PTFE or molydbenum disulphide of small particle size in a binder. Such coatings can be applied to fastener threads to replace metallic coatings such as zinc and cadmium and offer maintenance free permanent lubrication. By careful selection of the lubricants, AF coatings can be designed to meet specific applications. The coatings are permanently bonded to the metal surface and provide a lubricating film preventing direct metal to metal contact.
An anti-seize compound is used on the threads of fasteners in some applications. The purpose of the compound depends upon the application. It can prevent galling of mating surfaces - such compounds are frequently used with stainless steel fasteners to prevent this effect from occurring. In some applications it is used to improve corrosion resistance to allow the parts to be subsequently dis-assembled Thirdly, it can provide a barrier to water penetration since the threads are sealed by use of the compound.
A torque prevailing nut of an all metal construction. Covered by UK patent 1180842 the nut is marketed by GKN Screws and Fasteners Limited.
An intentional clearance between internal or external thread and the design form of the thread when the thread form is on it's maximum metal condition. Not all classes of fit have an allowance. For metric threads the allowance is called the fundamental deviation.
An adhesive which hardens in the absence of air, such adhesives are often used as a thread locking medium.
A tightening procedure in which a fastener is first tightened by a pre-selected torque (called the snug torque) so that the clamped surfaces are pulled together, and then is further tightened by giving the nut an additional measured rotation. Frequently bolts are tightened beyond their yield point by this method in order to ensure that a precise preload is achieved. Bolts of short length can be elongated too much by this method and the bolt material must be sufficiently ductile to cater for the plastic deformation involved. Because of the bolt being tightened beyond yield, its re-use is limited.
This is the theoretical profile of external and internal threads with no manufacturing tolerance applied.
The surface pressure acting on a joint face directly as a result of the force applied by a fastener.
A bolt or screw whose cross section of its head is in the shape of a 12 pointed star.
The word black refers to the comparatively wider tolerances employed and not necessarily to the colour of the surface finish of the fastener.
A bolt is the term used for a threaded fastener, with a head, designed to be used in conjunction with a nut.
The torque necessary to put into reverse rotation a bolt that has not been tightened.
The torque required to effect reverse rotation when a pre-stressed threaded assembly is loosened.
A specialist thread form based upon the Whitworth thread and consisting of 26 threads per inch whatever the thread diameter.
British Standard Fine. A thread form based upon the British Standard Whitworth form but with a finer thread (more threads per inch for a given diameter). This thread form was first introduced in 1908, the thread form is specified in BS 84: 1956.
British Standard Whitworth. A thread form developed by Sir Joseph Whitworth in 1841. The thread form has rounded roots and crests, the thread form is specified in BS 84: 1956. This thread form was superceded by the Unified thread in 1948 and then the metric thread form.
A modified thread profile patented and trade mark of the Bosco Tool Inc. The thread form has a small projection at the pitch diameter that eliminates the clearance from the thread assembly on both flanks. By doing this it is claimed that resistance to vibration loosening is significantly improved.
Coating of threaded fasteners with cadmium can provide the parts with excellent corrosion resistance. The appearance of the coating is bright silver or yellow if subsequently passivated. The friction values associated with this coating are also comparatively low. A chromate conversion coating is frequently applied to the surface to improve corrosion resistance. Cadmium is not now frequently used because of the environmental and worker health problems associated with the coating process and should not be used in applications above 250C or when contact with food is possible.
The compressive force which a fastener exerts on the joint.
The Class of Fit is a measure of the degree of fit between mating internal and external threads. Three main Classes of Fit are defined for metric screw threads :
FINE: This has a tolerance class of 5H for internal threads and 4h for external threads.
MEDIUM: This has a tolerance class of 6H for internal threads and 6g for external threads.
COARSE: This has a tolerance class of 7H for internal threads and 8g for external threads.
For Unified threads, a similar designation as for metric threads is used. The thread classes used are 1A, 2A and 3A for external threads and 1B, 2B and 3B for internal threads.
Cleveloc Nut
A torque prevailing nut of all metal construction. The collar of the nut is elliptical in cross section and it is this that provides the flexible locking element. The nut is pre-lubricated to reduce the torque needed when tightening and to minimise galling.
A dimensionless number representing the ratio of the friction force to normal force. Typically for threaded connections it is between 0.10 to 0,18 but can vary significantly depending upon the materials used and whether a lubricant has been used. In relation to threaded fasteners, the coefficent of friction can be further sub-divided into the coefficient of friction between the threads and the coefficient of friction under the nut face. There is in general a difference in values between the two coefficients due to typically the contact surfaces being different. For example, a zinc plated nut on a zinc plated bolt, the thread coefficent of friction would be due to zinc plating contacting zinc plating. The nut face coefficient of friction would be due to zinc plating contacting the joint surface finish.
A term used to describe the undesirable practice of mixing fasteners from different batches that are the same size and grade in the same container.
Cleveloc NutThe Coneloc is an all metal prevailing torque type self-locking nut. The locking action is achieved by localised precision deformation of the thread in the cone section on top of the nut. When the nut is tightened onto the bolt, the thread is gripped on the flanks providing the locking action. Coneloc is a trade mark of NUTS BOLTS Limited
This is an axial applied force applied to a nut when it is seated on a cone shaped washer which has an included angle of 120 degrees. Failure in this test is usually due to the nut splitting. The intention of the test is to introduce a nut dilation operation which will assess the potential detrimental effects of surface discontinuities. This type of test is sometimes applied to nuts which are intended for high temperature service.
Creep is deformation with time when a part is subjected to constant stress. Metals creep can occur at elevated temperature however with gasket materials it can occur at normal ambient temperatures. Creep resistance is an important property of gasket materials. Gasket materials are designed to flow under stress to fill any irregularities in the flange surface. The amount of creep sustained tends to increase with temperature. . However once the tightening is completed it is important that no further flow occurs since such deformation will lead to a reduction in bolt extension and subsequently the stress acting on the gasket. If this stress is reduced to below a certain minimum, which depends upon the type and construction of the gasket and the operating temperature, a high rate of leakage can be anticipated to occur.
The point at which there is zero pressure at the joint interface as a result of forces applied to the joint. If the applied force is increased beyond the decompression point, a gap will form at the interface. Analytically, a criteria of joint failure is often taken as when the applied force on the joint reaches the decompression point. This is because forces acting on the bolt(s) can dramatically increase at this point. Loading beyond this point can also result in fretting at the interface that will lead to bolt tension loss that will subsequently lower the decompression point. This process can continue until bolt failure does occur. The failure can be by fatigue or other mechanism but the underlying cause was loading of the joint beyond the decompression point. It is for this reason that it is frequently taken as a failure criteria in analysis work.
A high performance surface coating that can be applied to fasteners. The coating consists of passivated zinc flakes that are stoved onto the metal surface. The coating can be coloured and eliminates the risk of hydrogen embrittlement associated with electroplated metal. DACROMET is a registered trademark of Metal Coatings International, Inc. of Chardon Ohio
The design form of an internal or external thread is the thread form in it's maximum metal condition. It is the same as the basic thread profile except that the thread roots are rounded. If either the internal or external thread form exceeds the design form of the thread profile then a potential interference exists.
Direct Tension Indicators (DTI's) is a term sometimes used to describe load indicating washers. Projections on the face of the washer (usually on the face abuting the bolt head or nut) that deform under loading as the bolt is tensioned. An indication of the tension in the bolt can be made by measuring the gap between the washer face and the nut or bolt head. The smaller the gap - the greater the tension in the bolt. Commonly used in civil rather than mechanical engineering applications.
Resistance to relative movement of two bodies that are already in motion.
This is the diameter of an imaginary cylinder coaxial with the thread, which has equal metal and space widths. It is often referred to as pitch diameter. Sometimes referred to as the simple effective diameter to differentiate from the virtual effective diameter.
Twice the effective nut radius.
The radius from the centre of the nut to the point where the contact forces, generated when the nut is turned, can be considered to act.
A relatively thin, hard coating that can be applied to threads and deposited uniformly. Bright metallic in appearance this coating has excellent resistance to wear and corrosion.
Localized plastic deformation which occurs in the vicinity of clamped fasteners or in the fastener threads. . Embedding is local plastic deformations that occur under the nut face, in the joint faces and in the threads as a result of plastic flattening of the surface roughness. This occurs even when the loading is below the yield point of the bolt or limiting surface pressure of the joint material and is the result of the real area of contact between surfaces being less than the apparent area.
The lap that can be formed at the thread crest due to thread rolling.
A process that can occur with the use of high strength steel fasteners in which crack initiation and growth occurs in the fastener at a comparatively low stress level as a result of interactions that occur with the environment. Hydrogen is suspected of causing EAC in high strength steel fasteners, the hydrogen being produced as a result of chemical reactions (galvanic corrosion in a moist environment) or being present from a plating process that may have been applied to the fastener.
Forces exerted on a fastener as a result of an applied loading to the joint.
A screw thread which is formed on an external cylinder, such as on bolts, screws, studs etc.
A conventional flanged joint in which a gasket is compressed by bolts - the gasket is not rigidly located. Calculation methods such as the ASME code in the USA and the EN1591 code in Europe.
A low friction coating applied to threads. This type of coating is frequently used to prevent thread fouling when an assembly containing threaded fasteners is painted. Unless masked in some way before painting, electro deposited primers can cover the threads. If this occurs assembly difficulties can result unless the expensive chore of cleaning the threads is completed. A fluoro-carbon thread coating eliminates the need for masking or cleaning since paint will not adhere to the coating. This type of coating can also prevent problems caused by weld splatter obstructing the threads of weld nuts during their placement. Such coatings also have the property of reducing the torque-tension scatter during tightening.
Mechanical resistance to the relative movement of two surfaces. There are two main types of friction; STATIC FRICTION and DYNAMIC FRICTION. Typically static friction is greater than dynamic friction.
Coating materials used on fasteners with the intention of reducing the scatter in the thread and bearing surface friction coefficients.
An intentional clearance between internal or external thread and the design form of the thread when the thread form is on it's maximum metal condition. For metric threads the fundamental deviation are designated by letters, capitals for internal threads and small letters for external threads. Some tolerance classes have a fundamental deviation of zero. For imperial threads the fundamental deviation is called the allowance.
The fundamental triangle height is normally designated with the letter H. This is the height of the thread when the profile is extended to a sharp vee form. For 60 degree thread forms such as metric and Unified thread series, H equals 0.866025 times the thread pitch.
A severe form of adhesive wear which occurs during sliding contact of one surface relative to another. Clumps of one part stick to the mating part and break away from the surface. (Can frequently occur when both the nut and bolt are made from stainless or high alloy steels, titanium or zinc coated fasteners.)
Total distance between the underside of the nut to the bearing face of the bolt head; includes washer, gasket thickness etc.
A joint in which the plates and material between the nut and bolt bearing surfaces have a high stiffness when subjected to compression by the bolt load. A joint is usually defined as hard if the bolt is tightened to its full torque and it rotates through an angle of 30 degrees or less after it has been tightened to its snug condition.
The force under the head of a bolt or nut can exceed, at high preloads, the compressive yield strength of the clamped material. If this occurs excessive embedding and deformation can result in bolt preload loss. To overcome this hardened washers under the bolt head can be used to distribute the force over a wider area into the clamped material. A more modern alternative is to use a flange headed nuts and bolts.
Heat tightening utilises the thermal expansion characteristics of the bolt. The bolt is heated and expands: the nut is indexed (using the angle of turn method) and the system allowed to cool. As the bolt attempts to contract it is constrained longitudinally by the clamped material and a preload results. Methods of heating include direct flame, sheathed heating coil and carbon resistance elements. The process is slow, especially if the strain in the bolt is to be measured, since the system must return to ambient temperature for each measurement. This is not a widely used method and is generally used only on very large bolts.
A split type of spring washer whose purpose is to prevent self loosening of the nut or the bolt. The idea or principle behind the helical spring washer is for one end of the tang of the washer to indent into the fastener (the nut or bolt head) and the other into the joint surface so that any loosening rotation is prevented. Junker in his paper in 1969 on the cause of self-loosening of fasteners (reference:Junker, G., New criteria for self-loosening of fasteners under vibration. SAE Paper 690055, 1969) concluded that this type of lock washer has no ability to lock. This type of washer is sometimes called a spring lock washer or sometimes a standard lock washer.
Sometimes abbreviated to HSFG bolts. Bolts which are of high tensile strength used in conjunction with high strength nuts and hardened steel washers in structural steelwork. The bolts are tightened to a specified minimum shank tension so that transverse loads are transferred across the joint by friction between the plates rather than by shear across the bolt shank.
Special bolts that have a tang at the threaded end of the shank. This tang is gripped by the tightening tool during assembly so that the reaction torque is absorbed whilst the nut is tightened from the same side. Such bolts allow what used to have to be done by two men to become a one-man task.
This term is used for the completion of maintenance work on a bolted joint when the joint is under loading. This can involve the replacement of individual bolts. There are risks both to the joint itself and to health and safety associated with this technique.
A hydraulic tool used to tighten a fastener by stretching it rather than applying a large torque to the nut. After the fastener has been stretched, the nut is run down the thread to snug up with the joint, the hydraulically applied load is then removed resulting in tension being induced into the fastener.
Steel fasteners exposed to hydrogen can fail prematurely at a stress level well below the materials yield strength. Hydrogen embrittlement occurs in fasteners usually as a result of the part being exposed to hydrogen at some time during its manufacturing process but it can also occur through in-service corrosion. Electroplating is generally considered to be a major cause of hydrogen absorption in steel fasteners due to the release of hydrogen during this process. Higher strength steels are more susceptible to hydrogen embrittlement than lower strength steels, however it is considered that there is no lower strength limit. As a rule of thumb, steels below Rockwell C 35 are considered to be far less susceptible. Tests such as the incremental load hydrogen embrittlement test can be completed to assess if hydrogen embrittlement is present in a batch of fasteners.
A wrench, usually powered by electricity or air, in which repeated blows from little hammers are used to generate torque to tighten fasteners. The torque applied to the fastener depends upon the time and the air pressure applied to the tool (for pneumatic wrenches). The torque applied by an impact wrench to a fastener is influenced by the joint stiffness.
The point in space that an eccentrically shear loaded joint rotates about. The deformation and the load sustained by an individual bolt in a bolt group is dependent upon the distance that the bolt is from the instantaneous centre. The direction that the individual bolt force acts is perpendicular to a line joining that bolt to the instantaneous centre.
A term used to describe types of fasteners which are highly resistant to vibration loosening and/or removal. Some types have special thread forms.
A screw thread which is formed in holes, such as in nuts.
The name given to the reduction in the frictional resistance that occurs in a direction different to that inwhich slip is occurring. This effect is used in many applications including the removal of corks from bottles. If the cork is first rotated the force needed to pull the cork from the bottle is significantly reduced. It is also the fundamental reason why threaded fasteners experience self-loosening. Frictional resistance is first overcome in the transverse direction by slip occurring on the joint resulting in the frictional resistance in the circumferential direction reducing to a small value. The torque acting on the fastener in the loosening direction (as a result of its preload) that when coupled with the Jost Effect results in self-loosening occurring.

The term is named after the Institute that completed research into this effect, the Jost Institute of Tribotechnology at the University of Central Lancashire in the UK.

The factor in the torque tightening equation: T=KDF where T is the fastener tightening torque in Newton metres, D is the fastener diameter in metres, F is the fasteners preload in Newtons and K is a factor whose value is often taken as 0.2. The formula gives the approximate tightening torque for standard fasteners used under normal conditions. The K factor is also known as the nut factor and the torque coefficient.
A pre-assembled nut and washer assembly (the washer is attached to the nut so that it won't fall off)- a trademark of ITW Shakeproof. The origin of the word came from ShaKEProof. The s on the end being acquired due to them being purchased in quantities usually greater than one.
A screw thread that is screwed in by rotating counterclockwise.
The axial distance over which an external thread is in contact with an internal thread.
There are two common usage's of this term:
1. A nut which provides extra resistance to vibration loosening by either providing some form of prevailing torque, or, in free spinning nuts, by deforming and/or biting into mating parts when fully tightened.
2. The term is sometimes used for thin (or jam) nuts used to lock a thicker nut. When used in this way the thin nut should be adjacent to the joint surface and tightened against the thick nut. If placed on top of the thick nut the thin nut would sustain loads it was not designed to sustain.
This is the diameter of an imaginary cylinder parallel with the crests of the thread; in other words it is the distance from crest to crest for an external thread, or root to root for an internal thread.
The difference in tightening torque values produced by the same tightening tool on hard and soft joints. A hard joint typically gives a higher torque value than a soft joint. Generally speaking, the lower the meanshift of a tightening tool, the better it will be in achieving a specified torque value irrespective of the joint condition.
A flanged joint in which a gasket is compressed by bolts - the gasket being located in a recess within the joint so that it is compressed by the bolt loads until metal to metal contact occurs. Unlike the FLOATING TYPE FLANGE JOINT, for metal to metal type joints there are no standardised gasket factor definitions, test procedures, nor generally acknowledged calculation procedures available.
This is the diameter of an imaginary cylinder which just touches the roots of an external thread, or the crests of an internal thread.
A thread based upon the Whitworth thread form that was established in 1912. A very fine thread (a 3/32 inch thread having 60 tpi for example).
A solid lubricant that acts as a high pressure resistant film. Can be used by itself as a dry lubricant as well as in with other solid lubricants and in oils and greases. Used in threads, such lubricants act as a separating film to prevent corrosion formation on the thread surface (even under adverse temperature and environmental conditions) ensuring the release of the threaded connection. Such films can also act as friction stabilisers.
Nicks or indentations in threads can occur during the manufacturing process and during fastener transportation. In general, nicked thread problems tend to increase as the thread diameter increases and for fine pitches.
There are acceptance tests for nicked threads that involve measuring the maximum torque required to drive a GO gauge down the thread. Examples of acceptance tests are SAE J123 and the Ford Motor specification WA990 1993. Nicks and indentations in threads are sometimes referred to as gouges.
The diameter equal to the external diameter of the threads.
Under load, the wedging action of the threads causes dilation of the nut resulting in an increase in the minor diameter of the nut, and reducing the effective shear areas of both the external and internal threads.
A torque control fastener tightening tool that is usually powered by compressed air. The design of the tool is such that attempts are made to ensure that the applied torque is independent of joint stiffness.
Nyloc Nut
A torque prevailing nut that uses a nylon patented insert to provide a locking feature. The nylon insert, it is claimed, helps to seal the bolt thread against seepage of water, oil, petrol, paraffin and other liquids. The nut is covered by UK patent 8028437 and European patent 81303450-1. Nyloc is a registered trade name of Forest Fasteners.
A bolt or screw whose head cross section is a regular polygon with 8 sides.
Tapping of a thread following a plating operation so that the thread tolerances comply within specification allowing the internal and external threads to assemble. It is normal practice to overtap the internal rather than the external thread.
Term used in structural engineering for the joint plates.
The nominal distance between two adjacent thread roots or crests.
A single thickness of steel forming part of a structural joint.
Pooching is a term sometimes used to describe the effect of the area immediately surrounding a tapped hole being raised up as a result of the tension from the stud. Tapped holes are often bored out for the first couple of threads to eliminate this problem.
The tension created in a fastener when first tightened. Reduces after a period of time due to embedding and other factors.
The torque required to run a nut down a thread on certain types of nuts designed to resist vibration loosening. The resistance can be provided by a plastic insert or a noncircular head.
A type of lock nut which has a prevailing torque to assist in preventing self loosening. There are two main categories of prevailing torque nuts, all metal and nylon insert. All metal torque prevailing nuts generally gain a prevailing torque by distorting the threads at the top of the nut by some means. Nylon insert torque prevailing nuts ultilise a nylon (or other polymer) insert to achieve a prevailing torque.
The proof load of a nut is the axially applied load the nut must withstand without thread stripping or rupture. The proof load of a bolt, screw or stud is the specified load the product must withstand without permanent set.
A designation system which defines the strength of a bolt or nut. For metric fasteners, property classes are designated by numbers where increasing numbers generally represent increasing tensile strengths. The designation symbol for bolts consists of two parts:
1. The first numeral of a two digit symbol or the first two numerals of a three digit symbol approximates 1/100 of the minimum tensile strength in MPa.
2. The last numeral approximates 1/10 of the ratio expressed as a percentage between minimum yield stress and minimum tensile stress.
Hence a fastener with a property class of 8.8 has a minimum tensile strength of 800 MPa and a yield stress of 0.8x800=640 MPa.
The designation system for metric nuts is a single or double digit symbol. The numerals approximate 1/100 of the minimum tensile strength in MPa. For example a nut of property class 8 has a minimum tensile strength of 800 MPa. A bolt or screw of a particular property class should be assembled with the equivalent or higher property class of nut to ensure that thread stripping does not occur.
The amplification of an external force acting on a bolt by a lever action which can occur when that force is an eccentric tensile load.
A bolt whose shank diameter is smaller than the nominal diameter of the bolt (normally the shank diameter of such a bolt is approximately equal to the effective diameter of the thread).
The loss of clamping force in a bolt that occurs typically without any nut rotation occurring. Commonly occurs as a result of embedment but can also be due to gasket creep, metal creep (at elevated temperatures), differential thermal expansion and stress relaxation.
A screw thread that is screwed in by rotating clockwise. The majority of screw threads are right handed.
A thread formed by plastically deforming a blank rather than by cutting. The majority of standard fasteners have their threads formed by rolling. Most threads are rolled before any heat treatment operation. Significant improvements in fatigue life can be achieved by rolling the thread after heat treatment, this improvement is due to compressive stresses being induced in the roots of the thread. However, because of the increased hardness of the bolt blank, the die life can be significantly reduced. Rolling the thread also generally improves the surface finish which can have a beneficial effect on fatigue life.
A headed threaded fastener that is designed to be used in conjunction with a pre formed internal thread or alternatively forming its own thread. Historically, it was a threaded fastener with the thread running up to the head of the fastener that has no plain shank. However this definition has largely been superseded to avoid confusion over the difference between a bolt and a screw.
A ridge of constant section which is manufactured so that a helix is developed on the internal or external surface of a cylinder.
Threaded fasteners can come loose on occasions without human intervention. This loosening can be due to creep, embedding, stress relaxation or the fastener self-rotating (which is often called vibration loosening). Creep, embedding and stress relaxation will generally not completely loosen a fastener, these loosening mechanisms occur without the nut rotating relative to the bolt. The term self loosening is sometimes used for the nut rotating relative to the bolt without human intervention. It is know that the fastener can self rotate under the action of transverse joint movement that can completely loosen a tightened fastener such that the nut will become detached from the bolt.
A screw and washer assembly. A screw or bolt which has a captive washer. The washer is frequently loose on the plain shank of the fastener, the shank diameter being equal to the effective diameter of the thread; the thread being rolled from this diameter. The origin of the word is a frequent question. In the 1930's E. C. Crowther was a representative for a company that sold both shakeproof washers and screws. He came up with the idea of placing the washer on the screw before it was thread rolled. The major diameter of the screw being larger than the washer hole prevents it from coming off. The Illinois Tool Works made machines that produced these patented pre-asSEMbled washers and screws. The s at the end of SEMs is thought to have been subsequently picked up because they are not usually purchased individually. In spite of the original patents and trademarks the word SEMS is generally recognised as a generic term applicable to screw and washer assemblies.
A set screw is a threaded fastener that is typically used to hold a sleeve, collar or gear on a shaft to prevent relative motion. It is a threaded member that normally does not have a head. Unlike most other threaded fasteners it is basically a compression device normally used to generate axial thrust. Various socket types are provided to allow the set screw to be rotated. These types include hexagon socket, fluted socket, screwdriver slot and square head. Various point designs are available (the part of the set screw that rotates against the shaft being secured) and include:
Cup - Hollowed end, is the most commonly used point style. Used when the digging in of the point is not undesirable.
Cone - Pointed end, this type generates the highest torsional holding power and is typically used for a permanent connection.
Oval - Rounded end that is typically used when frequent adjustment is required. The oval end prevents/reduces indentation.
Flat - Cause little damage to the shaft and are used when frequent adjustment is required.
Dog - Flat end with the threads stopping short of the end with the end fitting into a hole.
That portion of a bolt between the head and the threaded portion.
A threaded fastener with a plain, precision machined, shank that is used for location purposes. They are typically used for pulleys and linkages.
The Skidmore-Wilhelm bolt tension calibrator is a hydraulic load cell used to determine the tension in a bolt or other threaded fastener. The tension in the bolt compresses fluid in a hydraulic cylinder, a pressure gauge connected to the cylinder is then calibrated to read in terms of force rather than pressure.
The torque required to pull plates together so that direct contact occurs; often used in angle control tightening. The snug torque ensures that metal to metal contact occurs at all the interfaces within the joint. It is only at this point that the required angle of rotation start in order that the bolt is tightened sufficiently. The snug torque is usually determined experimentally on the actual joint.
The process of pulling parts of a joint together, most of the input turn during this process is absorbed in the joint with little tension being given to the bolt.
A screw with a round head, usually with a hexagon indentation in the head for tightening purposes. Used on machine parts and is typically made from high strength steel (grade 12.9 in metric).
A joint in which the plates and material between the nut and bolt bearing surfaces have a low stiffness when subjected to compression by the bolt load. In such a joint, the bolt (or nut) typically has to be tightened by two or more complete turns, after it has been torqued to the snug condition, before the full tightening torque is achieved. Often the placement of a gasket in a joint results in a soft joint.
An alternative name, used by some manufacturers, for snug torque.
A type of gasket that is made by winding V-section metal strip and a softer filler material together. Support or retaining rings, inside and/or outside the spiral, improve the gasket's handling and fitting. The filler material used is typically graphite or PTFE. The metal strip and retaining rings being typically made from stainless steel.
Friction at rest; a force is required to initiate relative movement between two bodies - static friction is the force that resists such relative movement. Sometimes referred to as stiction.
The Step-Lock Bolt (SLB) is a thread form that has been modified to resist vibration loosening. The thread has several horizontal portions (i.e. no lead angle) whose purpose is to prevent torsion being developed in the bolt as a result of the loosening purpose. It is these horizontal portions that are known as steps. Published literature indicates that the thread form performs well when tested on a transverse vibration test machine. However manufacturing difficulties may prevent its widespread adoption.
A term used to describe a lock nut which has a prevailing torque.
The effective cross sectional area of a thread when subjected to a tensile force. It is based upon a diameter which is the mean of the pitch (or effective) and the minor (or root) diameters of the thread. The use of this diameter stems from the work of E. M. Slaughter in the 1930's. He completed carefully controlled tests using various sizes of standard threads and compared their strength with machined bars made from the same bar of material. He found that this mean diameter gave results that agreed with the tensile test results to within about 3%. The error on the minor and pitch diameters was about 15%. Tests completed subsequent to these by other investigators have also shown that the stress diameter is a reasonable approximation to a thread's tensile strength. (Referance: 'Tests on Thread Sections Show Exact Strengthening Effect of Threads.' by E. M. Slaughter, Metal Progress, vol 23, March 1933 pp. 18-20)
A significant problem with bolting at high temperatures is a phenomenon known as stress relaxation. Creep occurs when a material is subjected to high temperature and a constant load. Stress relaxation occurs when a high stress is present that is relieved over time; the stress is relaxed with a subsequent reduction in the bolt’s preload. The only way to minimise the effects of stress relaxation is to use materials that have an adequate resistance to it at the product’s operating temperature. The effect of bolt stress relaxation is to reduce the clamp force provided by the bolts; this phenomena alone will not fully loosen a joint.
A structural bolt is a heavy hexagon head bolt having a controlled thread length intended for use in structural connections and assembly of such structures as buildings and bridges. The controlled thread length is to enable the thread to stop before the joint ply interface to improve the fastener's direct shear performance.This term is used in civil and structural engineering but is not frequently used in mechanical engineering.
A fastener which is threaded at both ends with an unthreaded shank in between. One end (which often has a thread tolerance which results in more thread interference) is secured into a tapped hole, the other is used with a nut.
A symmetrical thread is one which has both flanks of the thread profile inclined at the same angle.
A method developed by four engineers of the Taylor-Forge Company in Chicago in the 1930's that subsequently formed the basis of the ASME code for flanged joint design. The assumptions made by the method are now generally regarded as too simplistic. This method gives rise to the m and y gasket factors.
A general name given to spring washers, curved washers, Belleville washers and disc springs. This type of washer provides a relatively low stiffness (compared to the joint stiffness) and can be used to act as a spring take-up with a bolt to prevent movement between parts.
The top part of the thread. For external threads, the crest is the region of the thread which is on it's outer surface, for internal threads it is the region which forms the inner diameter.
The thread flanks join the thread roots to the crest.
This is the distance between the minor and major diameters of the thread measured radially.
Length the portion of the fastener with threads.
The thread root is the bottom of the thread, on external threads the roots are usually rounded so that fatigue performance is improved.
The portion at the end of a threaded shank which is not cut or rolled to full depth, but which provides a transition between full depth threads and the fastener shank or head.
Can be a term used for a number of vibration resistant products but is now usually reserved for threadlocking adhesives. Specifically, a liquid anaerobic adhesive applied to nut or bolt thread, once hardened it fills the inner spaces between the threads to produce a solid plastic of a known shear strength.
Tin/zinc alloy coatings (typically 70% tin and 30% zinc) are applied to threaded fasteners to provide a corrosion resistant coating. One of the advantages of such coatings is that bimetallic corrosion will not occur when placed into contact with such metals as aluminium or steel.
A combination of tolerance grade and a fundamental deviation which is given to an internal or external thread. A tolerance class for an internal thread when combined with the tolerance class for an external thread gives the class of fit for the mating threads.
The difference between maximum and minimum metal conditions for a tolerance applied to a screw thread. For metric threads the tolerance grade is given a number.
A rotational moment; it is a measure of how much twisting is applied to a fastener. The units used to measure torque are in the form of force times length. Usually measured in newton-metres (Nm) if metric units are used or pounds feet (lb-ft) when imperial units are used.
A gearbox used to increase the torque produced by a small hand wrench.
A manual wrench which incorporates a gauge or other method to indicate the amount of torque transferred to the nut or bolt.
A U shaped fastener threaded at both ends used primarily in suspension and related areas of vehicles.
An instrument which can measure the change in length of a fastener ultrasonically as the fastener is tightened or measure the length before and after it is tightened).
Unified National Coarse (UNC) is a thread form with a 60 degree flank angle rounded roots and flat crests. For a given diameter it has a larger thread pitch than an equivalent diameter UNF thread. The unified thread is based on inch sizes and was first standardised in 1948 unifying the Whitworth and American standard thread forms.
Unified National Extra Fine (UNEF) is a Unified thread form with a very fine (small) pitch that are typically used on instruments and parts requiring a fine adjustment.
Unified National Fine (UNF) is a thread form with a 60 degree flank angle rounded roots and flat crests. For a given diameter it has a smaller thread pitch than an equivalent diameter UNC thread.
Unified National (UN) thread form with a rounded root contour, applies only to external threads. (The UN thread form has a flat, or optionally, a rounded root contour.) The majority of fasteners with a Unified thread form have a rounded root contour i.e. are UNR threads.
The effective diameter of a thread but allowing for errors in pitch and flank angles.
A bolt whose diameter is less than the minor diameter of the thread. Frequently the shank of the bolt is 0.9 times the root diameter.
A threaded insert that is typically used for tapped hole repair or to improve the thread stripping strength of softer metals such as zinc and aluminium. The inserts are assembled into a previously tapped hole using a special driving tool. A thread locking compound is frequently used to secure the insert if the assembly is subject to vibration.
A fastener tightening method which allows a fastener to be tightened to yield. The angle of rotation of the fastener is measured relative to the applied torque, yield being assessed when the slope of the relationship changes to below a certain value. Sometimes called joint controlled tightening.
Zinc electroplating is a common way to protect threaded fasteners from the effects of corrosion. Zinc electroplating can be completed in acid chloride, alkaline or cyanide baths. Supplemental coatings are frequently applied to zinc electroplating. These coatings, such as zinc phosphate or chromate conversion, provide a protective passivation layer on the zinc which assists in reducing the corrosion rate.
This coating is similar to zinc electroplating completed in an acid chloride bath - a small amount of cobalt (typically about 1%) is added to increase the plating speed.
A zinc phosphate conversion coating is frequently added to zinc electroplated parts, such as bolt threads, to improve corrosion resistance. This type of chemical conversion coating provides a protective passivation layer on the zinc improving its corrosion resistance.


Making its official debut this month, the new ExFab is a space where ideas are made into functioning devices.
Amin Arbabian
His team will develop a root imaging system where ultrasonic signals from roots are generated by radio signals and then recorded by a novel sensor array.
Recognized for contributions to cryptography and computer security, and to transactional memory and data center architecture.

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Realizing her fascination with neuroscience in the 8th grade, Iliana is laying a strong foundation to pursue her dreams. As an EE major, Iliana finds balance through the arts, and helping other undergraduates have a great Stanford experience. She's president of Fuse, the EE undergraduate student group, and she is involved with several other student groups and committees.


SHOULD COLLECTIVE BARGAINING BE DONE IN PUBLIC? At least when it comes to public workers negotiating for our tax dollars?  One initiative is aiming to do just that by requiring every school district to negotiate contracts in the sunshine.  I'll chat with Jon Caldara from the Independence Institute about just that.

DEAR BOULDER, DON'T BE SO STUPID PLEASE So Boulder is considering a "sustainability tax" that would fund things like composting programs, recycling, organic food production and other such nonsense.  During some recent polling, some idiots thought it would be a super idea to raise the millage rate on property tax to pay for this.  I just want to ask Boulderites if facing a lien on their home is worth supporting organic farming.  I'll explain.

SHOULD WHITES STOP TRYING TO "FIX" BLACK PEOPLE? The answer is yes according to this column by Wall Street Journal Editorial Board member Jason Riley, who is black.  I'll share some of this today because it's very interesting.  Of course it's racist, because Jason Riley is obviously some kind of Uncle Tom or something.

THE SOFT BIGOTRY OF LOW EXPECTATIONS Is it racist to think that young black men simply aren't reaching their potential?  Is it racist to assert they shouldn't be responsible for not reaching their potential?  This column certainly wants to maintain that young black men should not be held responsible for bad decision making.  It's not their fault and government should fix it.  Because that meme has worked so well for 50 years.  See the above column.

BEST CAMPAIGN AD EVER.  A young man in Alabama is running for the State House and he is challenging all kinds of preconceived notions about who he is as a Republican.  I. Love. This. Ad.

RUNNING SCARED AFTER WINNING BIG The oil and gas industry won big in Loveland when the fracking ban was voted down, but don't ask the anti fracktivists what happened.  In an unintentionally hilarious news story, they are trying really hard to turn those frowns upside down and come off as ridiculous in the process.  Read this quote:

“The oil and gas industry is running scared after nearly suffering a devastating loss on Tuesday,” Passanante said. “We are proud of the broad-based, bipartisan coalition of support that has come together to fight for clean air, pure water and a safe environment to raise our kids here in Colorado.”

That's right, they big victory has oil and gas "running scared".  I want to smoke what this guy is smoking.  For real.

NOT FOR NOTHING, BUT I SAID THIS And I wasn't alone.  Lots of conservatives made this point about Obamacare and the pressure it was going to put on primary care physicians.  See, there aren't enough doctors for everyone to have one.  That sounds horrible, but there simply aren't.  And according to this study, it's only going to get worse.  If you don't have a primary care doc, you may want to find one now before they all hit capacity.  Of course when I pointed this out years ago, it was because I was racist.  Or something.

WELL HERE'S AN UPSIDE TO LEGAL POT Speaking of things I've been saying for years, here's one.  Mexican drug cartels are hurting because of legal pot.  As in legal pot is putting some cartels out of business.  My heart bleeds for them.

THIS IS SO BAD I CAN'T EVEN MAKE FUN OF IT Watch what happens when Obama tries to show sympathy.  It's tragically, tragically pathetic.


This band's profile is 'invisible', meaning that it's much less prominent on the site - either because it's incomplete, or maybe doesn't entirely fit MS format.

NA-  Corky Gainsford - drums, vocals
2003-  Adrian Patrick - guitars, vocals
2003-  Ryan Patrick - guitars, vocals
2012-  Vassilios Metropoulos - bass, vocals
View timeline ››
NA-2012  Flavio Ivan Mendoza - bass
2003  Rainer Tuomikanto - drums
View timeline ››

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It's time for another "why the hell is this on a metal site?" moment, brought to you by Otherwise. True Love Never Dies - if that doesn't give a hint of what's in store, then chances you're the type of person who still uses child safety scissors as a grown adult. Or, you're like myself, and hoped prayed that the album title was conceived with some sense of irony. Too bad, here's some child-safety pop rock.   Review by Doc Godin ››

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Water Related Diseases And Contaminants In Private Wells

well water2Many people in the United States receive their water from private ground water wells. EPA regulations that protect public drinking water systems do not apply to privately owned wells. As a result, owners of private wells are responsible for ensuring that their water is safe from contaminants.

When rain falls, much of it is absorbed into the ground. Water that’s not used by plants moves downward through pores and spaces in the rock until it reaches a dense layer of rock. The water trapped below the ground in the pores and spaces above the dense rock barrier is called ground water, and this is the water we get when we drill wells. Another common term for ground water is “aquifer” or “ground water aquifer.”

Over 15 million U.S. households obtain their drinking water from private wells , which are not covered by the United States Environmental Protection Agency (EPA) regulations that protect public drinking water systems. Although the United States has one of the safest drinking water supplies in the world, sources of drinking water can still become contaminated through naturally occurring chemicals and minerals (for example, arsenic, radon), local land use practices (for example, pesticides, chemicals, animal feeding operations), malfunctioning waste water treatment systems (for example, sewer overflows), and other sources. Contamination of a private well can impact not only the household served by the well, but also nearby households using the same aquifer.

Owners of private wells are responsible for ensuring that their water is safe from contaminants. Private wells should be checked every year for mechanical problems, cleanliness, and the presence of coliform bacteria, nitrates, and any other contaminants of local concern. A local health department or water well systems professional can help ensure delivery of high-quality water from an existing well or, if needed, help locate and construct a new well in a safer area. Additional information about well maintenance and water testing is available at Healthy Water’s Well Testing page.

The presence of contaminants in water can lead to health issues, including gastrointestinal illness, reproductive problems, and neurological disorders. Infants, young children, pregnant women, the elderly, and people whose immune systems are compromised because of AIDS, chemotherapy, or transplant medications, may be especially susceptible to illness from some contaminants.

For more water-related diseases, see CDC Healthy Water’s Alphabetical Index of Water-related Health Data.

Source www.cdc.gov

Do it yourself test kits
DIY Water Testing kits from Amazon.com


TIME France

How France Has Changed Since the Charlie Hebdo Attack

January 7th marks the first anniversary of the attack

January 7th marks the first anniversary of the terror attack at the Charlie Hebdo offices in Paris. The attack, which killed eleven people and injured eleven others—including the satirical magazine’s cartoonist and editor-in-chief Stephane Charbonnier—devastated France and shook the entire world.

Vivienne Walt, a TIME correspondent in Paris, discusses how the people of France are still healing from the Charlie Hebdo attacks and the November terror attacks in Paris that killed 130 people. “This is a year that really redefined the way the French deal with just about everything,” she said.

Watch the video above to hear how a nation changed in one year.

Read about Charlie Hebdo’s special anniversary cover here.

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Table III Tool

The Table III Tool enables you to browse the United States Code Table III. For printing purposes, the PDF file is recommended. A detailed explanation of the Table is located here.

92d Cong.  ↑  86 Stat.  ↑  Feb. 15, 1972  ↑  92–231 92–233(pdf) 92–237
Act Section Stat. Pg. United States Code
Title Section Status
39 7 608c


24 Hours ONLY! $15 off your purchase. Get the code »

Inside Picture Books

Why do images from beloved childhood picture books linger in our minds? How do picture books shape our lives early on and even into adulthood? In this book Ellen Handler Spitz explores the profound impact of reading to children -- on the reader as well as the listener. She discusses well-known picture books and how they transmit psychological wisdom, convey moral lessons, shape tastes, and build a special bond between the child and the adult reader.

Currently there are no copies available. However, our inventory changes frequently. Please check back soon or try Book Fetch.


Canadian home prices hit a record high last month, with prices in already sky-high cities like Vancouver and Toronto driving the growth.

But, at the same time, the average income in Canada is not going up.

So how are Canadians paying for those expensive homes?

The CBC's Chris Brown went to find out. Click the video above to watch as he uncovers some creative solutions.


7 critical things to cover in your disaster-recovery plan

As always, you never know when a disaster will strike, so better to have a checklist on hand so that panic doesn’t set in when the network goes down.

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Edwards v Pepsico Company and Product Safety Essay

  • Length: 6 pages
  • Sources: 6
  • Subject: Business - Law
  • Type: Essay
  • Paper: #78776195

Excerpt from Essay :

Edwards v. Pepsico

Company and Product Safety Issue

In the case of Edwards v. Pepsico, 268 Fed. Appx. 756, 2008 U.S. App, Mr. Edwards had three fingers cut off of his dominant hand while working on a bulk bag unloading unit (BBU) at his place of employment, Whitlock Packaging Corporation, Inc. (Whitlock). His lawsuit claimed that, under Oklahoma state-law theories of manufacturers' product liability and gross negligence, defendants were responsible for design flaws in the BBU and a failure to warn of safety concerns.

At trial, the jury learned about the BBU and the roles played by the various defendants. The BBU was designed for Pepsi-Cola Company, a division of Pepsico, Inc. (Pepsi), as part of a system for the production of ready-to-drink beverages bottled under the Lipton Tea name. Pepsi pressed for a hastened manufacturing schedule because it had acknowledged bottled tea as a profitable product. The BBU holds a 1,600-pound sack of tea leaves and allows the leaves to flow through its rotary feeder component to unload a specified weight into a large brew basket.

Lockwood Greene Engineers (LGE), a design and procurement firm, created the initial design and, as Pepsi's agent, hired B.W. Sinclair, Inc. To manufacture ten of the systems. Wm. W. Meyer & Sons, Inc. (Meyer) entered into a contract with Sinclair to supply the BBU feeder component. During the bidding process, Meyer deleted a discharge guard for the feeder component from the quote at the request of a Sinclair manufacturing representative. Meyer delivered the feeders, with attached warning stickers, additional warning stickers, and manuals warning against operating the feeder without a guard on the discharge end and warning the user to keep hands away from the feeder. Sinclair integrated the feeders into the systems and delivered them to designated facilities. One of the ten systems was installed at Whitlock, which installed a guard on the feeder approximately two years before Mr. Edwards' injury but later took it off because it interfered with the flow of tea.

At the time of the incident, Mr. Edwards believed there was a clog in the BBU. He tried to fix the problem without shutting off the power or noticing the warning signs. He knelt down and placed his dominant hand into the unguarded discharge opening of the feeder. The rotating vanes inside the feeder sliced off his fingers. Mr. Edwards' experts testified that the unguarded moving blades of the feeder were unreasonably dangerous and that defendants had cost-effective, alternative-design options. They also claimed that the existing warnings were too small, blocked by hardware, or in the wrong place. Plaintiff's theory of the case was that speed and greed controlled the project rather than current engineering standards.

Defendants put on evidence indicating that, prior to Mr. Edwards' incident, there had been no reports of similar injuries to workers on any of the ten manufactured systems. An experienced manufacturing manager testified that he had never seen a guard on the discharge outlet of a BBU because there was no expectation that an operator would be near it. In addition, they established that Mr. Edwards was aware of Whitlock's safety rules prohibiting employees from putting their hands into moving machines and requiring employees to shut off power before working on equipment. The district court denied the defendants' motions for judgment as a matter of law on Mr. Edwards' claims for negligence and manufacturers' product liability. Before sending the case to the jury, however, the court dismissed the claim for punitive damages. The court also declined to give Mr. Edwards' two proposed instructions on the law of agency.

The jury returned a verdict against the Pepsi defendants and Sinclair, but in favor of LGE and Meyer. The jury awarded Mr. Edwards a total of $1,500,000. In allocating fault with regard to the negligence claim, the jury found Mr. Edwards 10% negligent, Pepsi 50% negligent, Sinclair 20% negligent, Whitlock (a non-party) 20% negligent, and LGE and Meyer 0% negligent. The district court entered judgment on the jury verdict.

Legal Theories

According to Oklahoma manufacturers' product liability law a plaintiff has to demonstrate three elements in order to be victorious: (1) the product was the cause of the plaintiff's injury; (2) a defect in the product existed at the time it left the defendants' ownership and control; and (3) the defect rendered the product unreasonably dangerous. The alleged defect may be the result of a problem in the product's design or manufacture, or it may be the result of inadequate warnings regarding use of the product. Also under Oklahoma law, a manufacturer's product liability claim applies to manufacturers, processors, assemblers, and all other persons who are likewise positioned in processing and distribution of the product. There is no legal support, however, for extending this principle and making all defendants within the chain of distribution automatically liable for a defective product. Rather, responsibility for the defect must still be traced to the proper defendant. Thus, which defendant is responsible for an alleged defect is determined in the trial court (Edwards v. Pepsico, 2008).

"A person required to pay damages to another must owe a legal duty to the injured person. This duty can be imposed by the federal or state constitution, federal or state statutes passed by the U.S. Congress or a state legislature, or the "common law." When an appeals court establishes a legal principle, this is known as the "common law" and is effective until it is overturned by a later decision or in some cases by Congress or the legislature. Manufacturers' products liability is part of the common law" (Walters, 2012).

In 1974, the Oklahoma Supreme Court recognized the theory of manufacturers' products liability in the case of Kirkland v. General Motors. Manufacturers' products liability is unlike than other forms of liability because it is strict liability. This means the defendant can be found legally responsible without fault. Therefore, a manufacturer can be legally responsible without bad intention, even if it followed present standards for its product. The statute of limitations, or time limit within which a case can be filed, goes from the date of personal injury or damage to property, and not from the time the product is sold to the end user (Walters, 2012).

In Kirkland, the court noted that the plaintiff must prove three elements to prevail in a product liability action:

"First, Plaintiff must prove that the product was the cause of the injury; the mere possibility that it might have caused the injury is not enough.

Secondly, Plaintiff must prove that the defect existed in the product, if the action is against the manufacturer, at the time the product left the manufacturer's possession and control. If the action is against the retailer or supplier of the article, the Plaintiff must prove that the article was defective at the time of sale for public use or consumption or at the time it left the retailer's possession and control.

Thirdly, Plaintiff must prove that the defect made the article unreasonably dangerous to him or his property as the term "unreasonably dangerous is ... defined" (Pearson, Wolfe, Whitmire & Anderson, 2002).

Oklahoma follows the consumer expectations test for figuring out if a manufacturer is legally responsible. This requires the claimant to establish that the product was (1) unreasonably hazardous (2) beyond the anticipation of the ordinary user (3) at the time it left the control and power of the manufacturer and (4) caused the damage. It is not enough that the product is hazardous. It must be unfairly dangerous from the point-of-view of its ordinary user. "Chain saws, lawn mowers, welding machines, gasoline, pesticides, kitchen utensils, natural gas and numerous other products are dangerous, but usually not unreasonably so. The ordinary consumer of the product is one who has knowledge of the characteristics of the product. Thus, whether a piece of construction or agricultural equipment is unreasonably dangerous is considered from the perspective of the average construction worker or farmer, not that of a teacher, accountant or clergy person" (Walters, 2012).

Although this is known as manufacturer's products liability, the theory of liability applies to everybody in the distribution network from the factory to the retail outlet. Therefore, an injured person has a claim against the retail seller, wholesaler, and importer of any product that causes harm without suing the manufacturer, which may be located in a part of the world where it is hard to serve with process. Each person who distributes the product, though, has a claim upstream against its resource for compensation for any costs of defending the claim and damages paid to the injured party (Walters, 2012).

The theory of liability applies to all products. Many cases today concern drugs, even though special rules apply to pharmaceuticals because customers rely on their health care providers and the FDA for their information about the effectiveness and safety of the drugs. Manufacturers' products liability is usually fair to sellers and customers. Yet, like all human activity, there are extraordinary cases which produce adverse publicity for the legal…

Cite This Essay:

"Edwards V Pepsico Company And Product Safety" (2012, May 16) Retrieved January 14, 2017, from

"Edwards V Pepsico Company And Product Safety" 16 May 2012. Web.14 January. 2017. <

"Edwards V Pepsico Company And Product Safety", 16 May 2012, Accessed.14 January. 2017,


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{system, computer, user}
{rate, high, increase}
{math, number, function}

In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. In other words a photon is a little packet of energy which can carry electromagnetic radiation. It is also the force carrier for the electromagnetic force. The effects of this force are easily observable at both the microscopic and macroscopic level, because the photon has no rest mass; this allows for interactions at long distances. Like all elementary particles, photons are currently best explained by quantum mechanics and will exhibit wave–particle duality, exhibiting properties of both waves and particles. For example, a single photon may be refracted by a lens or exhibit wave interference with itself, but also act as a particle giving a definite result when quantitative momentum is measured.

The modern concept of the photon was developed gradually by Albert Einstein to explain experimental observations that did not fit the classical wave model of light. In particular, the photon model accounted for the frequency dependence of light's energy, and explained the ability of matter and radiation to be in thermal equilibrium. It also accounted for anomalous observations, including the properties of black body radiation, that other physicists, most notably Max Planck, had sought to explain using semiclassical models, in which light is still described by Maxwell's equations, but the material objects that emit and absorb light are quantized. Although these semiclassical models contributed to the development of quantum mechanics, further experiments validated Einstein's hypothesis that light itself is quantized; the quanta of light are photons.

In the modern Standard Model of particle physics, photons are described as a necessary consequence of physical laws having a certain symmetry at every point in spacetime. The intrinsic properties of photons, such as charge, mass and spin, are determined by the properties of this gauge symmetry. The neutrino theory of light, which attempts to describe the photon as a composite structure, has been unsuccessful so far.

The photon concept has led to momentous advances in experimental and theoretical physics, such as lasers, Bose–Einstein condensation, quantum field theory, and the probabilistic interpretation of quantum mechanics. It has been applied to photochemistry, high-resolution microscopy, and measurements of molecular distances. Recently, photons have been studied as elements of quantum computers and for sophisticated applications in optical communication such as quantum cryptography.

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The 'voICe' App Eases Patient Communication in Clinical Environments

By: Rahul Kalvapalle - Oct 14, 2016
References: voice-intensivecare &
A group of Dutch innovators have created a new smartphone app, dubbed 'voICe', that is designed to ease patient communication among pediatric and adult patients who are unable to speak because they are on a ventilator or are breathing through a tracheostoma.

What makes this patient communication app so novel is the fact that it makes use of pictorial representations to represent speech and text at the same time, with the images being adapted to serve the needs of child patients. The app also allows for the incorporation of video messages from loved ones.

Good patient communication is key to improving patient comfort as well as boosting caregivers' ability to do their jobs, and this is exactly what the voICe app promotes.