2008年12月17日星期三

Marc Almond


Childhood and early life
Marc Almond was born on 9th July 1956 in Southport on the Lancashire coast between Liverpool and Blackpool, the son of Sandra Mary Almond (formerly Dieson) and Peter John Sinclair Almond, Second Lieutenant in the King's Liverpool Regiment. He was brought up at his grandparent's house in Birkdale with his younger sister Julia, and as a child suffered from bronchitis and asthma. When he was 4, they left their grandparent's house and moved to Starbeck on the edge of Harrogate, North Yorkshire. Two years later they returned to Southport, and then moved to Horsforth (near Leeds). Due to a car crash at the age of 14, Almond is nearly completely deaf in his left ear.
He just managed to scrape into King George V Grammar School in Southport. By this time his father was suffering from alcoholism, and Almond found solace in music, listening to British radio pioneer John Peel. The first album he purchased was the soundtrack of the stage musical Hair and the first single Green Manalishi by Fleetwood Mac. He became a great fan of Marc Bolan, Brian Eno and David Bowie and got a part-time job as a stable boy to fund his musical tastes.
He managed to gain two O-Levels in Art and English and was accepted onto a General Art and Design course at Southport College, specialising in Performance Art. He applied to Leeds Polytechnic where he was interviewed by Jeff Nuttall, also a performance artist, who accepted him on the strength of his mime skills.
It was whilst at Leeds Polytechnic that that Marc met David Ball a fellow student, forming Soft Cell in 1979.

Musical influences
As a child Marc listened to his parent's record collection, which included his mother's Let's Dance by Chris Montez and The Twist by Chubby Checker, also his father's collection of jazz including Dave Brubeck and Eartha Kitt. As an adolescent Marc listened to Radio Caroline and Radio Luxembourg. The first single he bought was The Green Manalishi by Fleetwood Mac, the first









帖子选项
本帖标签:
例如,踏板车、假期、秋天

album the soundtrack to the stage musical Hair. He became a great fan of Marc Bolan after hearing him on the John Peel Show, buying the T.Rex single Ride a White Swan, from then on he 'followed everything Marc Bolan did'. He was also a great fan of David Bowie, Roxy Music, Alice Cooper, Iggy Pop, Nico, the New York Dolls, Wayne County and Brian Eno. He went to Lou Reed, Captain Beefheart, and Cockney Rebel concerts in Liverpool. But the highlight was when he climbed over the barriers at the front of a David Bowie concert, reached out and was touched by the man himself.

Career and later life
Marc Almond has had a long and varied career spanning almost 30 years. During this time, after a career with Soft Cell and Marc and the Mambas, he has collaborated with an extremely wide range of artists including Antony and The Johnsons, Jools Holland, Siouxsie Sioux, Nick Cave, P.J. Proby, Nico, Kelli Ali of the Sneaker Pimps, Neal X (on the albums Fantastic Star and Open All Night), Marie France, Agnes Bernelle, Lydia Lunch, Gene Pitney on the #1 UK single "Something's Gotten Hold of My Heart", Foetus (a.k.a. J. G. Thirlwell), Jimmy Somerville of The Communards and Bronski Beat, Psychic TV, Coil, Sally Timms of the Mekons, King Roc, John Cale, David Johansen of The New York Dolls and German band Rosenstolz.
Almond initially shot to fame in the early 1980s as one half of synth duo Soft Cell, whose combination of drama and peep show sleaze set to an electronic beat gave them hits such as "Tainted Love" (UK #1), "Bedsitter" (UK #3), "Torch" (UK #2), "Say Hello Wave Goodbye" (UK #3), "Soul Inside" (UK # 16), "What?" (UK #3) and the club hit "Memorabilia". They were first spotted by David Oddie, boss of Wakefield based Ambergris Records in a Bradford club, who passed his enthusiasm onto Dead Good Records in Lincoln, famous for their Hicks From The Sticks compilation, who in turn approached Polygram , the newly formed amalgam of Polydor and Phonogram. Although Soft Cell disbanded in 1984 just before the release of fourth album, This Last Night In Sodom, the duo reunited in 2001 for live shows and in 2002 released a new album entitled Cruelty Without Beauty, from which the single "The Night" (UK #39) was taken.
His biggest UK hits as a solo artist have been cover versions; the aforementioned 1989 number one duet with Gene Pitney and another near chart-topper in 1991 with David McWilliams' "The Days of Pearly Spencer", which peaked at #4. In 1985, he duetted with Jimmy Somerville and Bronski Beat on a cover of Donna Summer's "I Feel Love (Medley)" and it hit #3. The highest UK positions his self-penned singles have reached so far have been "Stories of Johnny" (#23 in 1985), "Tears Run Rings" (#28 in 1988) and "Adored and Explored" (#25 in 1995).
Almond's work runs the gamut from electronica and dance music to French chanson, traditional piano ballads, and Russian romance songs, as exhibited on his 2003 album Heart on Snow. Influences include David Bowie, a childhood hero of his, as well as early 1960s Northern Soul and disco. Other major influences have been Scott Walker from the Walker Brothers and Jacques Brel, 12 of whose songs Almond reworked in English for his 1989 album Jacques. Almond's own lyrics are a creative expression of what he sees and are not to be confused with his own life. He also operates a record label, Blue Star Music, on which he has released many of his solo and collaborative records in the UK.
In 1999, Almond received attention and accolades for his autobiography, entitled Tainted Life, which confronts details of his early life, creative ventures, his sexuality (Almond is gay), and drug addiction, for which he was hospitalized in 1994. Almond wrote the autobiography without a ghost writer and his publishers subsequently commissioned him to write a travel book, In Search of the Pleasure Palace: Disreputable Travels, whose publication in 2004 was accompanied by a book-signing tour.
On 17 October 2004, Almond was badly injured in a motorbike accident in London, in which he was a pillion passenger. Although the initial prognosis was considered poor, he was discharged from Royal London Hospital on around 6 November 2004 and was said to be making a "remarkable" recovery. Two months later he was giving press and TV interviews saying he could not wait to get back on stage. His recovery was, however, to take longer than he thought, involving several operations and counseling for post traumatic stress disorder.
In 2005, he continued his recovery, did some DJ gigs all over Europe and guested at the Meltdown Festival in London in June 2005, hosted by Patti Smith. Almond contributed two songs to this night of Brecht music, "Bilbao Song" and "What Keeps a Man Alive". In October, November and December 2005, Almond went on tour with Jools Holland and his Rhythm & Blues Orchestra, singing two songs during the shows, "Say Hello Wave Goodbye" and "Tainted Love", which had a new arrangement done by Holland. 2006 saw Almond concentrate on recording, making few public appearances, though he did headline the Manchester Gay Pride Festival in August of that year. In 2005 he also contributed a track to the Serge Gainsbourg tribute album Monsieur Gainsbourg Revisited.
Almond's new album of cover songs, Stardom Road, was released on 4 June 2007, and features artists such as St Etienne's Sarah Cracknell and Antony from Antony and the Johnsons. Two of the cover versions included in this new album are Dusty Springfield's "I Close My Eyes and Count to Ten", which he has recorded with Sarah Cracknell, and Gene Pitney's over the top "Backstage (I'm Lonely)", as a tribute to the late crooner, featuring a guest appearance by Jools Holland. The album also includes one new self-penned song, "Redeem Me (Beauty Will Redeem the World)", his first composition since the near-fatal motorbike accident.
Marc also appears on the 2006 album Black Ships Ate the Sky by experimental band Current 93. He is also working on a DVD compilation of all his promotional video clips as well as his last ever self-penned album, tentatively titled Dining with Panthers, which is due to be completed in 2008.
Almond made his return to the London stage for a three-night run at the historic Wilton's Music Hall from May 4-6 2007, his first full-length UK shows since his accident. He had been warming up with shows in Barcelona, Athens and Moscow. He then recorded a BBC Radio special which was broadcast on Radio 2 on 1st June, and played a mini-tour in June and July, culminating in a 50th birthday concert before 2,000 fans and friends at Shepherd's Bush Empire in London on July 9th. The concert, a tour de force at nearly three hours on stage, had the audience in rapture. Marc himself was overcome with emotion on a couple of occasions especially when paying tribute to Gene Pitney.
On July 29, Marc made his first ever live appearance in his home town of Southport as a guest of Jools Holland's Rhythm and Blues Orchestra. He performed "Say Hello Wave Goodbye" and "Tainted Love".
Almond has been booked to perform at the British International Motor Show on August 1, 2008 at the ExCeL Exhibition Centre with Jools Holland.
Almond currently lives in the Bermondsey area of south east London. In his autobiography he describes previously living in Earl's Court, in a converted church in Fulham and most memorably in Soho's Berwick Street, where he lived in a flat overlooking the Raymond Revuebar.




Primary Lithium Battery


Magnetic Door Alarm


double coin tires


Handheld Metal Detectors


ash baseball bat


Roof Mount DVD


pex tubing fitting


Cotton Sateen Fabric


gas blow torch


Biodegradable Packing Material


heat press mug


Ratchet Tie Downs


Microwave Oven Bracket


Self Aligning Bearings


Bamboo Folding Chairs


DVB-T USB Receiver


threaded steel rod


CCTV Color Monitor


Nylon Fishing Line


replica wrist watches


hair extension kit


UHF TV Antenna


led under-cabinet light


jeep leaf springs


corrugated board box


nonstick broiler pan


Stained Glass Craft


floating golf balls


inflatable water ball


Polar Fleece Coat


Handmade Fabric Handbags


Double Wall Corrugated


evil eye beads


acrylic plastic beads


Short Sleeve Blouse


cotton children socks


curtain fabric silk


foam rubber cushion


dvbt usb receiver


Fastener Nut Bolt


jordan motorcycle jacket


moen replacement parts

ICT 1900

1900 Series computers
These varied in computing power and the models included:
ICT 1901
ICT 1902
ICT 1903
ICT 1904
ICT 1905
ICT 1906
ICT 1907
ICT 1909 (this machine had a hardware floating point arithmetic engine so it was suitable for scientific use.)
The first machine was in fact the 1904 which was a Canadian design from the Ferranti-Packard company, originally called the FP6000, although commonly referred to within West Gorton as the FP1. It is said that this machine with 'core store memory' fired up with its program still in store after its sea freight journey from Canada.[citation needed]
One feature of these mainframes was the common instruction set throughout the range meaning that programs written and compiled on one machine would run unchanged on any other. In fact the hardware was different between machines. To achieve this a program termed "the executive" or exec encapsulated the hardware and supplied software routines to supplement the hardware supplied instructions.
By 1968 ICT had merged with English Electric computers and become ICL.
Enhanced versions of the 1900 series subsequently appeared with an A suffix, an E suffix, an F suffix (for floating point), a T suffix, and an S suffix, e.g.
Stevenage designed and built machines, typically smaller system using the E3RM executive software
ICL 1901A
ICL 1901S/T
ICL 1902A
ICL 1902S
ICL 1902T
ICL 1903A
ICL 1903S
West Gorton (Manchester) built machines, typically larger system using the E6RM executive software
ICL 1903T
ICL 1904A
ICL 1904T
ICL 1904S
ICL 1906S
The 1900 Series were 24-bit word machines (supporting 4 6-bit characters per word) and using octal for binary short-hand, as opposed to the IBM Systems using 8-bit bytes and hex. Basic memory on the smaller machines was 16K words (or 64 kilobytes equivalent), and there were even 8K word versions sold (although most actually had 16K memory factory installed in readiness for the certain upgrade order that followed!) - early machines using 'core-store' memory (ferrite rings on a copper wire matrix) and operated on binary hand-switches on the mainframe cabinet. Despite the apparent small memory size, quite sophisticated applications were run on the equipment and computer programmers paid great attention to the efficient use (and reuse) of memory.
Input and output (I/O) consisted of 80 column cards (40 column cards - with round holes - were unable to cope with the full 64 character set), a card punch and 8-track paper tape; printed output was produced on a solid barrel line printer (120 columns wide).
The first commercial sale was made in 1964 to the Morgan Crucible Company and consisted of a 16k word 1902 with an 80-column 980 card/minute reader, a card punch, a 600 line/min printer and 4 x 20Kbs tape drives. It was soon upgraded to a 32K word memory and a floating point unit to allow for some scientific work. Incidentally this company was also the first business to order ICT's previous computer, the HEC4 (later ICT 1201) in 1955.
Disk capacity was also very limited, with early units supporting 4 or 8Mb removable multi-disc packs (first introduced on 1903 systems) (and Steve Hillel crashed the first unit when demonstrating it to his manager) and careful attention to ensuring the efficient use of disk space was common. Early machines used storage on reels of magnetic tape and were then augmented by direct access devices (disks) typically with disk capacities of 1.6Mb, 4Mb and 8Mb were the order of the day. By the time 30Mb packs were available they occupied a cabinet 4 feet (1.2 m) high (MEDS - Multiple Exchangeable Disk Store).
After ICL had introduced the "New Range" (NR) series of computers during the 70s, marketed as the 2900 series, the 1900 series actually lived on as there was such a wealth of software written for it:
The ICL 2903/2904, designed and built in Stevenage, which were really successors to the 1902A/3A machines as they had the same target instruction set (albeit with a native 32 bit rather than 24 bit architecture)
Second generation "S3E" (microcoded) versions of the larger NR systems (such as the 2960/2966 from West Gorton, and the later 2940/50 from Stevenage), could run 1900 series code under DME (Direct Machine Environment) as an emulation as well as the New Range instruction set under the newer VME (Virtual Machine Environment)
The later availability of CME (Concurrent Machine Environment) microcode, which allowed DME and VME to co-exist (and run) concurrently on the same platform, similar to the functionality offered by virtualisation software such as VMware today
The replacement for the 2903/4 was the ME29 (Machine Environment 29) with its own operating system, TME (Transaction Machine Environment), which could still execute 1900 applications
An update of CME to CME* in the 1980s to support a small VME range called DM1 that replaced the ME29, which could run TME within a VME VM (virtual machine)
Programming languages included the assembly type language PLAN (Programming LAnguage Nineteen-hundred) and latterly COBOL for the development of commercial-orientated systems while ALGOL and FORTRAN were used for scientific work.
The basic operating System was called "Executive" and supported "multiprogramming", i.e. it was capable of running as many as 4 programs concurrently, on the 1904 and larger machines. Later on (starting about 1968) advanced features (e.g. batch processing, spooling) were provided by a privileged ("trusted") program called GEORGE.

Instruction Set (1900)
The 1900 series machines were designed around a 'load-and-store' architecture.
Two address-modes were supported, one which used 15-bits and one which used 22-bits. This meant that a normal program written in '15AM' could use a maximum of 32768 words of data (32k) while a program written in '22AM' could address up to 4194304 (4m) words of data.
There were eight 24-bit registers (denoted r0 to r7), to address which three bits were required; the instruction code took up seven bits (000 to 177 in octal) of the word; registers 1, 2 and 3 could be used as 'modifiers' to the operand (requiring a further two bits, zero meaning no modifier) which left twelve bits for the operand itself. The registers occupied and were addressable as the first 8 words of memory.
If it was required to use more than a 12-bit operand, the required value could be loaded into r1,r2 or r3 and the respective register used as a modifier (index), which was added to whatever was put in the operand.
The instruction set was heavily word oriented - machine addresses represented words rather than 6-bit characters. Two instructions were provided for character manipulation: LDCH (LoaD CHaracter) and DCH (Deposit CHaracter). These used the two most significant bits of the address to specify which of the 4 six-bit characters of a word was to be loaded into, or deposited from, a register. As an instruction operand was only 12 bits long, these instructions were only useful if a modifier was also used.

Character Set
The basic character set was based around a 6-bit byte, which meant that only 64 different characters could be represented: upper case letters, the numbers 0 to 9 and a handful of other symbols. In the early days most output devices printed only in uppercase, and it was only with the advent of VDUs (Visual Display Units) that lower-case output started to become possible and printers began to support a 96-character set. To change case or output control codes a "3 shift" coding was used, character #74 (octal 74, "$" in the 64 character set) was used as "α shift" to indicate subsequent characters were uppercase, #75 ("]" in the 64 character set) was "β shift", indicating subsequent characters were lowercase and #76 ("↑") was "δ shift" and indicated the subsequent character was a control character (or one of "$", "]" or "↑"). For example the text "$200! You MUST be joking" would be encoded as ↑T200! Y]OU $MUST ]BE JOKING (Text was assumed to start in α shift (uppercase), δ shift "T" was displayed as "$").
The ICL ASCII codes for the symbols $ (dollar) £ (pound) and (hash) were different from the other major suppliers of computer equipment.


equipment ultrasonic welding


encapsulated o rings


rhinestone hair clip


Primary Lithium Battery


Magnetic Door Alarm


double coin tires


Handheld Metal Detectors


ash baseball bat


Roof Mount DVD


pex tubing fitting


Cotton Sateen Fabric


gas blow torch


Biodegradable Packing Material


heat press mug


Ratchet Tie Downs


Microwave Oven Bracket


Self Aligning Bearings


Bamboo Folding Chairs


DVB-T USB Receiver


threaded steel rod


CCTV Color Monitor


Nylon Fishing Line


replica wrist watches


hair extension kit


UHF TV Antenna

2008年12月12日星期五

Gas cylinder

Regulations and Testing
The transportation of high pressure cylinders is regulated by many governments throughout the world. Various levels of testing are generally required by the governing authority for the country in which it is to be transported. In the United States, this authority is the United States Department of Transportation (DOT). For Canada, this authority is Transport Canada (TC). Cylinders may have additional requirements placed on design and or performance from independent testing agencies such as Underwriter's Laboratory (UL). Each manufacturer of high pressure cylinders is required to have independent quality agent that will inspect the product for quality and safety.
There are a variety of tests that may be performed on various cylinders. Some of the most common types of tests are hydrostatic test, burst test, tensile strength, Charpy impact test and pressure cycling.
During the manufacturing process, vital information is usually stamped or permanently marked on the cylinder. This information usually includes the type of cylinder, the working or service pressure, the serial number, date of manufacture, the manufacture's registered code and sometimes the test pressure. Other information may also be stamped depending on the regulation requirements.
High pressure cylinders that are used multiple times--as most are--are hydrostatically or ultrasonically tested and visually examined every few years. In the U.S., hydrostatic/ultrasonic testing is required either every five years or every ten years, depending on cylinder and its service. Helium Gas tanks have the highest pressures possible when full around 1000 atmospheres.

Valve Connections When gases are supplied in gas cylinders, the cylinders have a stop angle valve at the end on top. Often, gas cylinders are somewhat long and narrow and may stand upright on a flattened bottom at one end with the valve at the top. During storage, transportation, and handling when the gas is not in use, a cap may be screwed over the protruding valve to protect it from damage or breaking off in case the cylinder were to fall over. Instead of a cap, cylinders commonly have a protective collar or neck ring around the service valve assembly.
When the gas in the cylinder is ready to be used, the cap is taken off and a pressure-regulating assembly is attached to the stop valve. This attachment typically has a pressure regulator with upstream (inlet) and downstream (outlet) pressure gauges and a further downstream needle valve and outlet connection. The upstream pressure gauge indicates how much gas is left in the cylinder according to pressure. The regulator could be adjusted to control the flow of gas out of the cylinder according to pressure shown by the downstream gauge. The outlet connection is attached to whatever needs the gas supply, such as a balloon for example.
The valves on industrial, medical and diving cylinders are usually of different size and type, as are the valves for different products, making it more difficult to mistakenly misuse a gas.
In the US, valve connections are sometimes referred to as 'CGA connections,' since the Compressed Gas Association (CGA) publishes guidelines on what connections to use for what products (e.g., In the USA, an argon cylinder will have a CGA 580 connection on the valve).
Note: if the nut on a CGA connection has a notch in it, it uses a left-handed thread.
High purity gases will sometimes use CGA-DISS ('Diameter Index Safety System') connections.
In the EU, DIN connections are more common than in the US.

Color Coding
Gas cylinders are often color coded, but the codes are not standard across different jurisdictions, and sometimes are not regulated. Cylinder color should not be used for positive product identification. Gas cylinders have labels affixed to them which identify the product they contain and the label alone should be used for positive identification. When the identification provided by the label is dubious, it should be marked Contents Unknown and the manufacturer or distributor should be contacted to assist in identifying the cylinder contents.

Safety and standards
Because the contents are under pressure and are sometimes hazardous, there are special safety regulations for handling bottled gases. These include chaining bottles to prevent falling and breaking, proper ventilation to prevent injury or death in case of leaks and signage to indicate the potential hazards. Installing and replacing gas cylinders should be done by trained personnel.
In a fire, the pressure in a gas cylinder rises in direct proportion to its temperature (see the ideal gas law). If the internal pressure exceeds the mechanical limitations of the cylinder and there are no means to safely vent the pressurized gas to the atmosphere, the vessel will fail mechanically. If the vessel contents are ignitable, this event may result in a "fireball". If the cylinder's contents are liquid but become a gas at ambient conditions, this is commonly referred to as a Boiling Liquid Expanding Vapour Explosion (BLEVE).
Medical gas cylinders in the UK and other countries have a seal of Wood's metal between the valve block and the cylinder body. This seal melts at a comparatively low temperature (70°C) and allows the contents of the cylinder to escape in a controlled fashion, lessening the risk of explosion.
More common pressure relief devices are of a simple burst disc type. In these, a small burst disc is installed in the back of the valve. A burst disc is a small metal gasket engineered to rupture at a pre-determined pressure. Some of these burst disc are backed with a low-melting-point metal, so that the valve must be exposed to excessive heat before the burst disc can rupture.
If the valve of a compressed air cylinder is broken or sheared off, the released pressure will cause the cylinder to act like a rocket, shooting away quickly.
The Compressed Gas Association sells a number of booklets and pamphlets on safe handling and use of bottled gases. (Members of the CGA can get the pamphlets for free.)



electrical meter socket


exhaust pocket bike


Teak Garden Set


flexible duct connector


Intra Oral Camera


washed leather jacket


Knitting Machine Needles


chocolate fondue sets


zigzag sewing machine


Ladies' Casual Jacket


Citric Acid Anhydrous


christmas hanging ornament


rhinestone hair clips


Female USB Connector


CCTV DVR Card


Cast Iron Scrap


Steel Pipe Elbow


flanges forged steel


ear clip headphone


Ladies Casual Jacket


Backpacking Sleeping Bag


equipment ultrasonic welding


encapsulated o rings


rhinestone hair clip


Primary Lithium Battery


Magnetic Door Alarm

Nondestructive testing

The need for NDT
It is very difficult to weld or mold a solid object that has the risk of breaking in service, so testing at manufacture and during use is often essential. During the process of casting a metal object, for example, the metal may shrink as it cools, and crack or introduce voids inside the structure. Even the best welders (and welding machines) do not make 100% perfect welds. Some typical weld defects that need to be found and repaired are lack of fusion of the weld to the metal and porous bubbles inside the weld, both of which could cause a structure to break or a pipeline to rupture.
During their service lives, many industrial components need regular non-destructive tests to detect damage that may be difficult or expensive to find by everyday methods. For example:
Aircraft skins need regular checking to detect cracks;
Underground pipelines are subject to corrosion and stress corrosion cracking;
Pipes in industrial plants may be subject to erosion and corrosion from the products they carry;
Reinforced concrete structures may be weakened if the inner reinforcing steel is corroded;
Pressure vessels may develop cracks in welds;
The wire ropes in suspension bridges are subject to weather, vibration, and high loads, so testing for broken wires and other damage is important.
Finished machined parts, such as bearings, that have newly been assembled can be tested for missing pieces, such as a ball or roller bearing, or grease within the housing non-destructively with a checkweigher. A roller motor for a conveyor can be tested for the proper level of oil, without disassembling the finished product. Thousand of manufactured products can benefit from this form of testing.
Over the past centuries, swordsmiths, blacksmiths, and bell-makers would listen to the ring of the objects they were creating to get an indication of the soundness of the material. The wheel-tapper would test the wheels of locomotives for the presence of cracks, often caused by fatigue — a function that is now carried out by instrumentation and referred to as the acoustic impact technique.
Use of X-rays for NDT is a common way of examining the interior of products for voids and defects, although some skill is needed in using radiography to examine samples and interpret the results. Soft X-rays are needed for examining low density material like polymers, composites and ceramics.

Notable events in early industrial NDT
1854 Hartford, Connecticut: a boiler at the Fales and Gray Car works explodes, killing 21 people and seriously injuring 50. Within a decade, the State of Connecticut passes a law requiring annual inspection (in this case visual) of boilers.
1895 Wilhelm Conrad Röntgen discovers what are now known as X-rays. In his first paper he discusses the possibility of flaw detection.
1880 - 1920 The "Oil and Whiting" method of crack detection is used in the railroad industry to find cracks in heavy steel parts. (A part is soaked in thinned oil, then painted with a white coating that dries to a powder. Oil seeping out from cracks turns the white powder brown, allowing the cracks to be detected.) This was the precursor to modern liquid penetrant tests.
1920 Dr. H. H. Lester begins development of industrial radiography for metals. 1924 — Lester uses radiography to examine castings to be installed in a Boston Edison Company steam pressure power plant .
1926 The first electromagnetic eddy current instrument is available to measure material thicknesses.
1927 - 1928 Magnetic induction system to detect flaws in railroad track developed by Dr. Elmer Sperry and H.C. Drake.
1929 Magnetic particle methods and equipment pioneered (A.V. DeForest and F.B. Doane.)
1930s Robert F. Mehl demonstrates radiographic imaging using gamma radiation from Radium, which can examine thicker components than the low-energy X-ray machines available at the time.
1935 - 1940 Liquid penetrant tests developed (Betz, Doane, and DeForest)
1935 - 1940s Eddy current instruments developed (H.C. Knerr, C. Farrow, Theo Zuschlag, and Fr. F. Foerster).
1940 - 1944 Ultrasonic test method developed in USA by Dr. Floyd Firestone.
1950 J. Kaiser introduces acoustic emission as an NDT method.
(Source: Hellier, 2001) Note the number of advancements made during the WWII era, a time when industrial quality control was growing in importance.
Methods and techniques
NDT is divided into various methods of nondestructive testing, each based on a particular scientific principle. These methods may be further subdivided into various techniques. The various methods and techniques, due to their particular natures, may lend themselves especially well to certain applications and be of little or no value at all in other applications. Therefore choosing the right method and technique is an important part of the performance of NDT.
Terminology
Indication
The response or evidence from an examination, such as a blip on the screen of an instrument.
Interpretation
Determining if an indication is of a type to be investigated. For example, in electromagnetic testing, indications from metal loss are considered flaws because they should usually be investigated, but indications due to variations in the material properties may be harmless and nonrelevant.
Flaw
A type of discontinuity that must be investigated to see if it is rejectable. For example, porosity in a weld or metal loss.
Evaluation
Determining if a flaw is rejectable. For example, is porosity in a weld larger than acceptable by code?
Defect
A flaw that is rejectable — i.e. does not meet acceptance criteria. Defects are generally removed or repaired.
(Source: ASTM E1316 in 'Vol. 03.03 NDT)

Reliability and statistics
Defect detection tests are among the more commonly employed of non-destructive tests. The evaluation of NDT reliability commonly contains two statistical errors. First, most tests fail to define the objects that are called "sampling units" in statistics; it follows that the reliability of the tests cannot be established. Second, the literature usually misuses statistical terms in such a way as to make it sound as though sampling units are defined. These two errors may lead to incorrect estimates of probability of detection.


electrical meter socket


exhaust pocket bike


Teak Garden Set


flexible duct connector


Intra Oral Camera


washed leather jacket


Knitting Machine Needles


chocolate fondue sets


zigzag sewing machine


Ladies' Casual Jacket


Citric Acid Anhydrous


christmas hanging ornament


rhinestone hair clips


Female USB Connector


CCTV DVR Card


Cast Iron Scrap


Steel Pipe Elbow


flanges forged steel


ear clip headphone


Ladies Casual Jacket


Backpacking Sleeping Bag


equipment ultrasonic welding


encapsulated o rings


rhinestone hair clip


Primary Lithium Battery


Magnetic Door Alarm

GroEL

GroEL belongs to the chaperonin family of molecular chaperones, and is found in a large number of bacteria. It is required for the proper folding of many proteins. To function properly, GroEL requires the lid-like cochaperonin protein complex GroES. In eukaryotes the proteins Hsp60 and Hsp10 are structurally and functionally nearly identical to GroEL and GroES, respectively.
Mechanism
Within the cell, the process of GroEL/ES mediated protein folding involves multiple rounds of binding, encapsulation, and release of substrate protein. Unfolded substrate proteins bind to a hydrophobic binding patch on the interior rim of the open cavity of GroEL, forming a binary complex with the chaperonin. Binding of substrate protein in this manner, in addition to binding of ATP, induces a conformational change that allows association of the binary complex with a separate lid structure, GroES. Binding of GroES to the open cavity of the chaperonin induces the individual subunits of the chaperonin to rotate such that the hydrophobic substrate binding site is removed from the interior of the cavity, causing the substrate protein to be ejected from the rim into the now largely hydrophilic chamber. The hydrophilic environment of the chamber favors the burying of hydrophobic residues of the substrate, inducing substrate folding. Hydrolysis of ATP and binding of a new substrate protein to the opposite cavity sends an allosteric signal causing GroES and the encapsulated protein to be released into the cytosol. A given protein will undergo multiple rounds of folding, returning each time to its original unfolded state, until the native conformation or an intermediate structure committed to reaching the native state is achieved. Alternatively, the substrate may succumb to a competing reaction, such as misfolding and aggregation with other misfolded proteins.

Thermodynamics
The constricted nature of the interior of the molecular complex strongly favors compact molecular conformations of the substrate protein. Free in solution, long-range, non-polar interactions can only occur at a high cost in entropy. In the close quarters of the GroEL complex, the relative loss of entropy is much smaller. The method of capture also tends to concentrate the non-polar binding sites separately from the polar sites. When the GroEL non-polar surfaces are removed, the chance that any given non-polar group will encounter a non-polar intramolecular site are much greater than in bulk solution. The hydrophobic sites which were on the outside are gathered together at the top of the cis domain and bind each other. The geometry of GroEL requires that the polar structures lead, and they envelop the non-polar core as it emerges from the trans side.

Structure
Structurally, GroEL is a dual-ringed tetradecamer, with both the cis and trans rings consisting of seven subunits each. The inside of GroEL is hydrophobic, and is likely where protein folding takes place.
The key to the activity of GroEL is in the structure of the monomer. The Hsp60 monomer has three distinct sections separated by two hinge regions. The apical section contains a large number of hydrophobic binding sites for "native" (unfolded) protein substrates. Many globular proteins won't bind to the apical domain because their hydrophobic parts are clustered inside, away from the aqueous medium since this is the thermodynamically optimal conformation. Thus, these "substrate sites" will only bind to proteins which are not optimally folded. The apical domain also has binding sites for the Hsp10 monomers of GroES.
The equatorial domain has a slot near the hinge point for binding ATP, as well as two attachment points for the other half of the GroEL molecule. The rest of the equatorial section is moderately hydrophilic.
The addition of ATP and GroES has a drastic effect on the conformation of the cis domain. This effect is caused by flexion and rotation at the two hinge points on the Hsp60 monomers. The intermediate domain folds down and inward about 25° on the lower hinge. This effect, multiplied through the cooperative flexing of all monomers, increases the equatorial diameter of the GroEL cage. But the apical domain rotates a full 60° up and out on the upper hinge, and also rotates 90° around the hinge axis. This motion opens the cage very widely at the top of the cis domain, but completely removes the substrate binding sites from the inside of the cage.



electrical meter socket


exhaust pocket bike


Teak Garden Set


flexible duct connector


Intra Oral Camera


washed leather jacket


Knitting Machine Needles


chocolate fondue sets


zigzag sewing machine


Ladies' Casual Jacket


Citric Acid Anhydrous


christmas hanging ornament


rhinestone hair clips


Female USB Connector


CCTV DVR Card


Cast Iron Scrap


Steel Pipe Elbow


flanges forged steel


ear clip headphone


Ladies Casual Jacket


Backpacking Sleeping Bag


equipment ultrasonic welding


encapsulated o rings


rhinestone hair clip


Primary Lithium Battery


Magnetic Door Alarm

Backpack

Terminology
The word backpack was coined in the United States in the 1910s. Knapsack and packsack were used before; they now occur mainly as regionalisms in North America. The word rucksack is a German loanword mainly used in the UK: 'der Rücken' means 'the back' (the part of the body) in German. The name Rucksack is cognate with Danish Rygsæk, Norwegian Ryggsekk, Dutch Rugzak, and Swedish Ryggsäck. Alternative names include Haversack, and Bergen (from the manufacturer's name Bergens, used for a backpack supported by an external frame, usually associated with the British Armed Forces).
Backpacks can often simply be referred to as "packs", especially in outdoors contexts; though sometimes ambiguous compared to other bags such as saddlebags and duffel bags, context is generally sufficient for identification.

Backpack designs
Backpacks in general fall into one of three categories: frameless, external frame, and internal frame. A pack frame, when present, serves to support the pack and distribute the weight of its contents across the body more easily (generally by transferring much of the weight to the hips and legs), so most of the weight does not rest on the shoulders, restricting range of motion and possibly causing damage from pressure on the straps. Most are capable of being closed with either a buckle mechanism or a zipper, though a few models use a drawstring for the main compartment. Many Backpacks with shoulder straps can affect a humans posture if carrying more than 30 pounds.

Frameless
The simplest backpack design is a bag attached to a set of shoulder straps. Such packs are used for general transportation of goods, and have variable capacity. The simplest designs consist of one main pocket. This maybe combined with webbing or cordage straps; while more sophisticated models add extra pockets, waist straps, chest straps, padded shoulder straps, padded backs, and sometimes reflective materials for added safety when the wearer is out at night. In general these packs can be produced inexpensively.
Some outdoors packs, particularly those sold for day hikes, ultralight backpacking and mountaineering are sometimes frameless as well.

External frame packs

The more traditional type of frame pack uses a rigid external frame which is strapped on the back and in turn carries and supports a cloth or leather sack and potentially strapped on items. External frames were traditionally used to carry heavy loads (20 kg / 40 lb and more), giving the wearer more support and protection and better weight distribution than a simple, frameless strapped bag. Wooden pack frames have been used for centuries around the world (Ötzi the Iceman may have used one in Copper Age Alpine Italy , though some archaeologists believe the frame found with the body was part of a snowshoe), and such gear was common in military and mountaineering applications right up to the 20th century ; metal versions first appeared in the mid-20th century, and plastic designs towards the turn of the 21st. Modern pack frames are usually made from lightweight metal tubes, generally aluminium but sometimes also using titanium or scandium alloys. The frame typically has a system of straps and pads to keep the sack and the frame from contacting the body. The open structure has the added benefit of improved ventilation and decreased sweatiness. The fabric part of the pack occupies part of the frame's length, but the frame typically protrudes above and below. These areas of the frame allow bulky items (such tents, sleeping bags, and thermal pads) to be strapped on. Thus the main compartment is smaller than that of an internal-frame pack, because bulky items (tents, sleeping bags, thermal pads) are strapped to the parts of the frame not occupied by the main compartment itself. This may result in a less smooth load (annoying in dense forest) and less control over the movement of the center of gravity of the pack. While less popular than internal-frame gear, some manufacturers (such as Kelty, Jansport, and Coleman) continue to produce external packs, and military packs are often external-frame designs as well.

Internal frame packs
The internal frame backpack is a recent innovation, invented in 1967 by Greg Lowe, who went on to found Lowepro, a company specializing in backpacks and other carrying solutions for various equipment. An internal-frame pack has a large cloth section in which a small frame is integrated. This frame generally consists of strips of either metal or plastic that mold to one's back to provide a good fit, sometimes with additional metal stays to reinforce the frame. Usually a complex series of straps works with the frame to distribute the weight and hold it in place. The close fitting of the back section to the wearer's back allows the pack to be closely attached to the body, and gives a predictable movement of the load; on the downside, the tight fit reduces ventilation, so these type of packs tend to be more sweaty compared to external frame packs. The internal construction also allows for a large storage compartment. Internal-frame packs may provide a few lash points (including webbing loops and straps for sleeping bags and other large items), but as the frame is fully integrated and not available on the outside, it is difficult to lash a large, heavy item so that it stays fixed and does not bounce, so most cargo must fit inside. Internal-frame packs originally suffered from smaller load capacity and less comfortable fit during steady walking, but newer models have improved greatly in these respects. In addition, because of their snug fit, they ride better in activities that involve upper-body movement such as scrambling over rocky surfaces and skiing. The improved internal frame models have largely replaced external frame backpacks for many activities.

Backpacks in daily use
In many countries, backpacks are heavily identified with students, and are a primary means of transporting educational materials to and from school. In this context they are sometimes known as bookbags or schoolbags. The purchase of a suitably fashionable, attractive, and useful backpack is a crucial back-to-school ritual for many students.
Typical school backpacks generally lack the rigid frame of an outdoor-style backpack and include only a few pockets in addition to the main holding space of the pack. While traditionally very simple in design, school backpacks are often made with padded straps and backs as well as additional reinforcement to hold large numbers of heavy textbooks, as well as safety features such as reflective panels to make the wearer of the pack more visible at night. It is very common for schools (especially colleges and universities) to sell backpacks decorated with the school logo.
Specialist ergonomic back packs are available that are designed to protect young backs and distribute the weight across the strongest muscles and relieve pressure on the neck and spine.
Backpacks are sometimes worn as fashion accessories, in which they perform the same function as a purse.Some such backpacks designed specifically for women are no larger than a typical purse, and are generally associated with younger, often college-age women.

Special-purpose backpacks
Some backpacks are specifically designed to carry certain items. Common examples include backpacks for small, high-value items such as laptops and cameras (see photo); backpacks designed to hold laptop computers in particular generally have a padded compartment to hold the computer and are especially common in college and university settings. It is also possible to buy "picnic basket" backpacks that come with plastic dishes and utensils, a tablecloth, etc. In order to supply these devices with electricity, some backpacks are equipped with solar panels.
Backpacks (often made of clear plastic) are sometimes used as a type of packaging, particularly for educational toys and games targeted at children. In retail settings, loss prevention rules sometimes require employees to use clear plastic backpacks (as well as purses) to carry materials to and from work to prevent loss by employee theft.
There are also single-strap packs that are essentially a hybrid between a backpack and a messenger bag.
Inexpensive, very simple packs that combine the drawstring and straps into a single piece of cloth or webbing are occasionally sold for use at sporting events and the like. Some high-end retailers (notably Apple Stores) use a similar design for their shopping bags as well.
Rolling backpacks are backpacks with wheels on the bottom and an extending handle to ease carrying objects inside the backpacks. Because of its design, rolling backpacks reduce the strain on one's back, which is more ergonomic than regular backpacks, though rolling backpacks can be carried on the back as well.

Backpacks for professional use
Backpacks are a standard part of the carrying equipment of soldiers, especially infantry, in most countries, and military-style packs are regularly available to civilians in military surplus stores. Well-known examples include the United States ALICE field pack and the British Army PLCE rucksack attachment, both of which are widely available to civilian markets both as actual military surplus (new or used) and as replicas. Such packs are often, though not always (e.g. the USMC's ILBE pack), external-frame packs, with the pack itself lashed or pinned to a metal or plastic carrying frame.
Many police tactical units, as well as players of military-style combat games such as paintball and airsoft, use military-style backpacks and webbing for storing gear and ammunition. There is also a small but thriving industry devoted to creating historical reproductions of military gear; such companies generally produce period-appropriate uniforms and other gear in addition to backpacks.
Some more recent military/tactical designs, especially the MOLLE and ILBE packs used by the United States armed forces, are covered with webbing loop attachment points for increased carrying capacity.

Backpacks for leisure and travel
Backpacks are sometimes used as luggage, particularly as carry-on bags for airplane travel.
Backpacks form an essential part of the gear of the outdoor trekker and the urban backpacker, allowing more mobility and compactness than would be available to someone carrying most of their gear and clothing in a suitcase.
In addition to their use in outdoors pursuits, backpacks are sometimes used in other sports as well. Hydration packs, sometimes used by runners and bicyclists, carry water (in either a bladder or a rigid bottle) and have a tube connected to them from which the wearer can drink without removing the pack; this feature is also included in some more general-purpose hiking backpacks. Backpacks that carry skateboards have also become more popular in the youth culture.

Backpacks for outdoor activities
One common special type of backpack (sometimes referred to as a "technical pack" or "frame pack") is designed for backpacking and other outdoors activities. These type of packs are more complex than most other backpacks. Compared to backpacks used for more day-to-day purposes such as schoolbooks, such packs are designed to carry substantially heavier loads, and as a result most such packs attach not only at the shoulders but at the hips, using a padded hip belt to distribute the majority of the weight of the pack to the legs and not the back. The often heavily padded and sometimes semi-rigid shoulder straps are mainly for balancing the weight. They usually (except for those used in ultralight backpacking) have a metal or plastic frame to support and distribute the weight of the pack. Larger packs of this type tend to have a subdivided main compartment. These trekking packs often have several pockets on the outside; they may also have lash points on the exterior (either directly attached to the frame or webbing loops), so that bulky items may be strapped on, although depending on the pack design and type of trek most backpackers will try to stuff everything into the pack. Multiday packs typically have a content between 60 and 100 liters (and are about 3ft /1 meter tall). Smaller packs with similar features are available for shorter trips.
The most common materials for such packs are canvas and nylon, either ripstop fabric for lightweight packs or heavier fabric such as cordura for more typical usage. Most such packs are purpose-designed for the outdoors market; however, it is not uncommon for military surplus packing gear to be sold to outdoorspeople as well for the same purpose. The cheaper versions of the outdoor packs are often favoured by city trekkers; as they have a large volume and still carry relatively easily.
Outdoors packs, in addition to the distinction between external-frame and internal-frame, can be further subdivided based on the duration of trip a pack might be expected to be used on; daypacks hold supplies for a single day's hiking (size about 20-30 litres), while "weekender" bags can hold two to three day's worth of gear and supplies (sizes about 40-50 litres). Larger packs generally have no specific names but are designed to distribute the weight of increased numbers of gear and supplies for longer-duration trips (60-100 litres); such packs often include complex ergonomic support features to simplify the carrying of large amounts of weight. A third type with little or no frame at all, similar to the bookbags used by students and made of light fabric (often nylon ripstop, as mentioned above), is used in ultralight backpacking to eliminate the weight of the frame and heavy fabric used in more typical outdoors packs. Despite (or perhaps because of) their lesser weight, such packs are seldom less expensive than more typical, regular-weight packs.
In addition, outdoors packs are designed for specific purposes such as kayaking/canoeing, rock climbing, mountaineering, cross country skiing, and other such activities. Packs used in competitive strategic sports such as paintball and airsoft are often based on or actually are military gear.



electrical meter socket


exhaust pocket bike


Teak Garden Set


flexible duct connector


Intra Oral Camera


washed leather jacket


Knitting Machine Needles


chocolate fondue sets


zigzag sewing machine


Ladies' Casual Jacket


Citric Acid Anhydrous


christmas hanging ornament


rhinestone hair clips


Female USB Connector


CCTV DVR Card


Cast Iron Scrap


Steel Pipe Elbow


flanges forged steel


ear clip headphone


Ladies Casual Jacket


Backpacking Sleeping Bag


equipment ultrasonic welding


encapsulated o rings


rhinestone hair clip


Primary Lithium Battery


Magnetic Door Alarm

1880s in fashion


Women's fashion
Overview

As in the previous decade, emphasis remained on the back of the skirt, with fullness gradually rising from behind the knees to just below the waist. The fullness over the buttocks was balanced by a fuller, lower bosom, achieved by rigid corseting, creating an S-shaped silhouette.
Skirts were looped, draped, or tied up in various ways, and worn over matching or contrasting underskirts. The polonaise was a revival style based on a fashion of the 1780s, with a fitted, cutaway overdress caught up and draped over an underskirt. Long, jacket-like fitted bodices called basques were also popular for daywear.
Evening gowns were sleeveless and low-necked (except for matrons), and were worn with long over the elbow or shoulder length gloves of fine kid leather or suede.
Choker necklaces and jewelled collars were fashionable under the influence of Alexandra, Princess of Wales, who wore this fashion to disguise a scar on her neck.
Bodices were very tight fitted as a result of darts and princess seams.In the early 1800’s dropped waists were common; creating a very long torso. Most ended in a point just below the waist. Collars that were very high and banded were very popular. These types of collars were called “officers collars’.-Landis1234

Underwear
The bustle returned to fashion and reached its greatest proportions ca. 1886-1888, extending almost straight out from the back waist to support a profusion of drapery, frills, swags, and ribbons. The fashionable corset created a low, full bust with little separation of the breasts.
The usual undergarment was a combination, a camisole with attached knee- or calf-length drawers, worn under the corset, bustle, and petticoat. Woolen combinations were recommended for health, especially when engaging in fashionable sports such as riding or tennis.

Outerwear
Riding habits had become a "uniform" of matching jacket and skirt worn with a high-collared shirt or chemisette, with a top hat and veil. They were worn without bustles, but the cut of the jacket followed the silhouette of the day.
In contrast, hunting costumes were far more fashionably styled, with draped ankle-length skirts worn with boots or gaiters.
Tailored costumes consisting of a long jacket and skirt were worn for travel or walking; these were worn with the bustle and a small hat or bonnet. Travelers wore long coats like dusters to protect their clothes from dirt, rain, and soot.

Aesthetic dress
Artistic or Aesthetic dress remained an undercurrent in Bohemian circles throughout the 1880s. In reaction to the heavy drapery and rigid corseting of mainstream Paris fashion, aesthetic dress focused on beautiful fabrics made up simply, sometimes loosely fitted or with a belt at the waist. Aesthetic ideas influenced the tea gown, a frothy confection increasingly worn in the home, even to receive visitors.

Hairstyles and headgear
Hair was usually pulled back at the sides and worn in a low knot or cluster of ringlets; later hair was swept up to the top of the head. Fringe or bangs remained fashionable throughout the decade, usually curled or frizzled over the forehead.
Bonnets resembled hats except for their ribbons tied under the chin; both had curvy brims.

Men's fashion

Coats, jackets, and trousers
Three piece suits consisting of a sack coat with matching waistcoat (U.S. vest) and trousers (called in the UK a "lounge suit") continued as an informal alternative to the contrasting frock coat, waistcoat and trousers.
The cutaway morning coat was still worn for formal day occasions in Europe and major cities elsewhere, with a dress shirt and an ascot tie. The most formal evening dress remained a dark tail coat and trousers with a dark waistcoat. Evening wear was worn with a white bow tie and a shirt with a winged collar.
In mid-decade, a more relaxed formal coat appeared: the dinner jacket or tuxedo, which featured a shawl collar with silk or satin facings, and one or two buttons. Dinner jackets were appropriate when "dressing for dinner" at home or at a men's club.
The Norfolk jacket was popular for shooting and rugged outdoor pursuits. It was made of sturdy tweed or similar fabric and featured paired box pleats over the chest and back, with a fabric belt.
Full-length trousers were worn for most occasions; tweed or woollen breeches were worn for hunting and other outdoor pursuits.
Knee-length topcoats, often with contrasting velvet or fur collars, and calf-length overcoats were worn in winter.
By the 1880s the majority of the working class, even shepherds adopted jackets and waistcoats in fustian and corduroy with corduroy trousers, giving up their smock frocks.

Shirts and neckties
Shirt collars were turned over or pressed into "wings". Dress shirts had stiff fronts, sometimes decorated with shirt studs, and buttoned up the back.
The usual necktie was the four-in-hand and or the newly fashionable Ascot tie, made up as a neckband with wide wings attached and worn with a stickpin.
Narrow ribbon ties were tied in a bow, and white bowtie was correct with formal evening wear.

Accessories
As in the 1870s, top hats remained a requirement for upper class formal wear; bowlers and soft felt hats in a variety of shapes were worn for more casual occasions, and flat straw boaters were worn for yachting and other nautical pastimes.
Shoes of the 1880s had higher heels and a narrow toe.

Children's fashion
Young girls wore dresses with round collars and sashes. Fashionable dresses had dropped waists. Pinafores were worn for work and play. When going out, especially in the winter, girls wore lots of layers to keep warm. A warm coat was worn with kid leather gloves. A muff hand warmer was worn over the gloves, so when the girl removed her hands her gloves would keep them warm. Just like ladies, all upper-class Victorian girls wore gloves when going out. A hat or bonnet was worn as well, along with long, knee-length button-up boots or shorter boots with gaitors to give the appearance of wearing long boots.
Older boys wore knee-length breeches and jackets with round-collared shirts.

Bose headphones


Background

Acoustic Noise-Cancellation Development
The idea of personal noise protection by actively controlled headphones was originally documented in a 1960 Russian patent application. In the United States, the idea for active noise cancellation for helicopter and aircraft pilots was patented by Dr. Lawrence J. Fogel as early as the mid 1950s U.S. Patent 2,866,848 , U.S. Patent 2,920,138 , U.S. Patent 2,966,549 and Canadian patent 631,136. According to Bose, the company started noise-cancellation involvement after Dr. Amar Bose went on a 1978 flight to Europe, utilized the headphones provided during the flight only to conclude that he couldn't really enjoy the sound with the roar of engines in the background.".
In 1986, Bose applied their noise-cancellation technology to develop headphones to protect the hearing of pilots participating in the first non-stop around-the-world flight.
One source notes that "nearly simultaneously, the US company Bose and Sennheiser in Germany presented active headsets for aircraft pilots," citing a 1986 American Society of Mechanical Engineers paper about the Bose product and a 1988 Funkschau (see de:Funkschau) paper about the Sennheiser. Bose's first noise-cancelling headsets were released to the public in 1989.
After about 10 years of research and development Bose released their first consumer level noise reducing headphones for pilots called the Aviation Headset, released in 1989. The current revision provides active equalization as well as active noise reduction.
Like all such technology, it mixes an inverted sample of the ambient sound outside the headset with the sound that reaches the inside of the headset, partially cancelling out the noise. Active (battery-powered) noise cancellation is never perfect, and is better at low frequencies than at high frequencies.
As with all active noise cancellation technologies, it requires a source of power—a small battery inside the headset—to perform the cancellation.

Bose TriPort Earcup Structure
The "triport" earcup structure has three miniature air ducts that allow the drivers to make larger excursions without resulting in distortion. The design was first used in the Bose Aviation Headset X "Magellan" released in 1998 and is now used in all of the company's headphone products.
All Bose headphones are closed-air to provide passive noise reduction.
QuietComfort Headphones

Bose QuietComfort 2 Headphones "Second Edition"

The Bose QuietComfort 2 Second Edition was introduced August 2005. The earcup color was changed to silver, "acoustic equalization" was added, and the earcups now incorporate magnetic shielding.
The QC2 is powered by a single AAA battery inside the right earcup with a built-in attenuator. The cord can be detached at the user's discretion for stand-alone noise cancellation.
JAL provides Bose QuietComfort 2 Headphones for use by passengers in premium flight classes on some long-haul flights.
A cellphone adapter has been made available to users for the second edition and QC3 headphones.

Bose QuietComfort 3 Headphones

Bose released the QuietComfort 3 Acoustic Noise Cancelling Headphones on June 15, 2006, the company's first pair of supra-aural (on-the-ear) headphones.
Bose states that, although the supra-aural configuration provides less passive blocking than their circumaural headphones, the QC3s have the same amount of total noise reduction as the QC2s due to improved active noise cancellation. In 2006, they were the first headphones to receive a Sound & Vision Editor's Choice award.
The QC3 appears to achieve its active noise cancellation performance at the expense of stability of causing an unpleasant squealing noise as described on these following flaws:
Pressure on the earpads, such as that caused by the user leaning their head against a flat surface.
Manually pressing on the headphones.The QC3 uses memory foam to conform to the ear and provide a good acoustic seal without uncomfortable pressure.
The QC3's earcups are too small to contain a AAA battery, and are powered by a rechargeable lithium-ion battery instead. Bose claims a battery life of twenty hours, about half that of the QC2.
Bose QC3 headphones are provided by American Airlines for use by passengers in premium flight classes on some long-haul flights.On 11 January 2008, Engadget revealed that Bose was going to release a Bluetooth adapter for the QC3. No information was given on a QC2 Bluetooth version.

Bose TriPort Headphones

Bose Around-Ear (AE) Headphones

Introduced in 2002and originally called the TriPort headphones, they were renamed the Bose Around-Ear (AE) Headphones in October 2006. The Bose Around-Ear headphones don't have active noise cancellation (as opposed to the QuietComfort 2 headphones). For a short time, the Bose Around-Ear headphones were also sold with a Bose-badged CD player as a part of the company's "TriPort CD Music System".
A New York Times reviewer commented that "the research effort paid off: the [Bose Around-Ear Headphones] has very full sound and works equally well with all types of music," but judged a competitor's headset, priced at less than half the price of the AE's, to be "just as comfortable and just as light, and the sound it produced was just as full and clear."A few months after the release of the iPhone in 2007 Bose redesigned the AE's headphone jack to make it iPhone compatible

Bose On-Ear (OE) Headphones
The Bose On-Ear headphones were introduced on October 12, 2006. The Bose On-Ear is similar to the Bose QuietComfort 3 Headphones, but without active noise cancellation. The cord is detachable; both 43 and 16-inch cords are available.
Shortly after the release of the iPhone in 2007 Bose redesigned the OE's headphone jack on the detachable cords to make it iPhone compatible.

Bose In-Ear (IE) Headphones

The Bose In-Ear headphones were introduced on October 12, 2006 as the company's first earbud product. Three eartips of different sizes are included. Bose claims that the IE's silicone tips are shaped to fit the ear's natural curves more closely.

The TriPort airducts in this product consist of two air ducts in the large grille, and one "stand-alone" air duct on top of each earbud.
After customer complaints stating that the "silicone ear tips become detached under certain conditions" and that the "stability of the headphones during certain activities, such as exercise, could be improved", Bose setup a website to send redesigned ear tips and a new clip and the lanyard for free.

IE v2
On March 15th, 2007 Bose redesigned the headphones which fixed many of the issues with the silicone ear tip stability. The cord for the redesigned headphones is now black and white to signify the change.

IE v3
Shortly after the release of the iPhone, on October 11, 2007, Bose redesigned the IE's for a 3rd time. They made the headphone jack iPhone compatible and removed the circuit board from the headphone jack and moved it up the cord. Bose also included a clip and a lanyard on this revision as well.

Bose Aviation Headset X "Explorer"
The original Bose Aviation Headset X ("ten") was released in 1998. This was Bose's first product using "triport" technology, and according to Bose was lighter in weight, used less headband force, had better sound, and better noise reduction than Bose's previous aviation headset.
Aviation Headset X was voted #1 by Professional Pilot magazine's headset preference survey five years in a row from 2000 to 2005.
The July 2003 "Explorer" model added improvements in the "down cable" assembly (including the boom microphone and battery pack).
Bose offers an accessory for this model which allows the headphone to be permanently installed in the aircraft and eliminates the need for battery power, and offers trade-up programs for earlier models.

Combat Vehicle Crewman Headset
In 1993 Bose introduced an active noise reduction system for use by crews in United States Army armored vehicles.
At noise levels of 115dBA SPL, Bose noise cancelling headsets improves speech intelligibility scores to 95%, compared to 80% for conventional headsets.At low frequencies, Bose headsets are much more effective in attenuating noise than passive noise reduction headsets. A binaural talk-through feature allows crewmen to talk directly to each other without removing their headsets.
This product is not available to civilian consumers.

Bose QuietComfort and American Airlines
American Airlines provides QuietComfort 3 headphones to first- and business-class passengers on some long-haul flights. Bose has made American Airlines several special edition versions of the QuietComforts starting with the original QC1 that had blue ear cups and an American Airlines logo on them. American Airlines became the first airline to offer the QuietComforts.
American Airlines allows each of their First and Business Class passengers to use a pair of the QuietComfort 3 on long-haul flights to Europe, Asia, deep South America and select First Class transcontinental flights.
On 1 July 2006JAL started to offer QuietComfort 2 headphones to First class customers on some flights
Air-India also offers QuietComfort 3 headphones to its Premium Class customers on some long haul flights.

Awards
2000 to 2005 Aviation Headset X was voted #1 by Professional Pilot magazine's headset preference survey five years in a row.
2004 Red Dot Award for product design on QuietComfort 2
2006 QuietComfort 3 were the first headphones to receive a Sound & Vision Editor's Choice award.
2006 Potentials Magazine Gold Star Award] for the QuietComfort 3

2007 Red Dot Award for product design] on QuietComfort 3
Criticism
Critics have said:
The QuietComfort headphone models have a high price tag.
The QuietComfort headphones are incapable of unpowered operation, unlike some competitive products which operate passively, without noise reduction, when unpowered.
The QuietComfort 3 have "earcan" instability and has half the battery life of the QuietComfort 2.
Early versions of the TriPort headphones were fragile and subject to headband and earcup cracks.
in Late 2005 TriPort Headphones were re-designed to address these problems with a P3 label on the package. TriPorts are now called the Bose Around-Ear Headphones and have these improvements included.
Some complaints about the early production In-Ears have been that the "silicone ear tips become detached under certain conditions" and that the "stability of the headphones during certain activities, such as exercise, could be improved", Bose setup a website to send redesigned ear tips and a new clip and the lanyard for free.
The Bose in-ear headphones are only audio headphones and have no noise cancellation technology.

Hydraulic cylinder


Operation
Hydraulic cylinders get their power from pressurized hydraulic fluid, which is typically oil. The hydraulic cylinder consists of a cylinder barrel, in which a piston connected to a piston rod moves back and forth. The barrel is closed on each end by the cylinder bottom (also called the cap end) and by the cylinder head where the piston rod comes out of the cylinder. The piston has sliding rings and seals. The piston divides the inside of the cylinder in two chambers, the bottom chamber (cap end) and the piston rod side (rod end) chamber. The hydraulic pressure acts on the piston to do linear work and motion.
A hydraulic cylinder is the actuator or "motor" side of this system. The "generator" side of the hydraulic system is the hydraulic pump which brings a fixed or regulated flow of oil into the system. Mounting brackets in the form of flanges, trunnions, feet and clevisses are mounted to the cylinder body. The piston rod also has mounting attachments to connect the cylinder to the object or machine component that it is pushing. Trunnion mounts are sometimes fitted along the body of a hydraulic cylinder.
By pumping hydraulic oil to the bottom side of the hydraulic cylinder, the piston rod starts moving upward. The piston pushes the oil in the other chamber back to the reservoir. If we assume that the oil pressure in the piston rod chamber is zero, the force on the piston rod equals the pressure in the cylinder times the piston area (F=PA).
If the oil is pumped into the piston rod side chamber and the oil from the piston area flows back to the reservoir without pressure, the pressure in the piston rod area chamber is Pull Force/(piston area - piston rod area). In this way the hydraulic cylinder can both push and pull.

Parts of a hydraulic cylinder
A hydraulic cylinder consists of the following parts:

Cylinder barrel
The cylinder barrel is mostly a seamless thick walled forged pipe that must be machined internally. The cylinder barrel is ground and/or honed internally.

Cylinder Bottom or Cap
In most hydraulic cylinders, the barrel and the bottom are welded together. This can damage the inside of the barrel if done poorly. Therefore some cylinder designs have a screwed or flanged connection from the cylinder end cap to the barrel. (See "Tie Rod Cylinders" below) In this type the barrel can be disassembled and repaired in future.

Cylinder Head
The cylinder head is sometimes connected to the barrel with a sort of a simple lock (for simple cylinders). In general however the connection is screwed or flanged. Flange connections are the best, but also the most expensive. A flange has to be welded to the pipe before machining. The advantage is that the connection is bolted and always simple to remove. For larger cylinder sizes, the disconnection of a screw with a diameter of 300 to 600 mm is a huge problem as well as the alignment during mounting.

Piston
The piston is a short cylinder shaped metal component that separates the two sides of the cylinder barrel internally. The piston is usually machined with grooves to fit elastomeric seals. These seals are often O-rings or U-cups. They prevent the pressurized hydraulic oil from passing by the piston to the chamber on the opposite side. This difference in pressure between the two sides of the piston cause the cylinder to extend and retract. Piston seals vary in design and material according to the pressure and temperature requirements that the cylinder will see in service.

Piston Rod
The piston rod attaches to the piston and extends from the cylinder through the rod end head. In double rod end cylinders, the actuator has a rod extending from both sides of the piston and out both ends of the barrel. The piston rod connects the hydraulic actuator to the machine component doing the work. This connection can be in the form of a machine thread or a mounting attachment such as a rod clevis or rod eye. These mounting attachments can be threaded or welded to the piston rod or, in some cases, they are a machined part of the rod end.


Rod Gland
The cylinder head is fitted with seals to prevent the pressurized oil from leaking past the interface between the rod and the head. This area is called the rod gland. It often has another seal called a rod wiper which prevents contaminants from entering the cylinder when the extended rod retracts back into the cylinder. The rod gland also has a rod bearing. This bearing supports the weight of the piston rod and guides it as it passes back and forth through the rod gland. In some cases, especially in small hydraulic cylinders, the rod gland and the rod bearing are made from a single integral machined part.

Other parts
Cylinder bottom connection
Seals
Cushions
A hydraulic cylinder should be used for pushing and pulling only. No bending moments or side loads should be transmitted to the piston rod or the cylinder. For this reason, the ideal connection of a hydraulic cylinder is a single clevis with a spherical ball bearing. This allows the hydraulic actuator to move and allow for any misalignment between the actuator and the load it is pushing.

Hydraulic Cylinder Designs
There are primarily two styles of hydraulic cylinder construction used in industry: tie rod style cylinders and welded body style cylinders.

Tie Rod Cylinders
Tie rod style hydraulic cylinders use high strength threaded steel rods to hold the two end caps to the cylinder barrel. This method of construction is most often seen in industrial factory applications. Small bore cylinders usually have 4 tie rods, while large bore cylinders may require as many as 16 or 20 tie rods in order to retain the end caps under the tremendous forces produced. Tie rod style cylinders can be completely disassembled for service and repair.
The National Fluid Power Association (NFPA) has standardized the dimensions of hydraulic tie rod cylinders. This enables cylinders from different manufacturers to interchange within the same mountings.

Welded Body Cylinders
Welded body cylinders have no tie rods. The barrel is welded directly to the end caps. The ports are welded to the barrel. The front rod gland is usually threaded into or bolted to the cylinder barrel. This allows the piston rod assembly and the rod seals to be removed for service.


Welded body cylinders have a number of advantages over tie rod style cylinders. Welded cylinders have a narrower body and often a shorter overall length enabling them to fit better into the tight confines of machinery. Welded cylinders do not suffer from failure due to tie rod stretch at high pressures and long strokes. The welded design also lends itself to customization. Special features are easily added to the cylinder body. These may include special ports, custom mounts, valve manifolds, and so on.
The smooth outer body of welded cylinders also enables the design of multi-stage telescopic cylinders.
Welded body hydraulic cylinders dominate the mobile hydraulic equipmment market such as construction equipment (excavators, bull dozers, and road graders) and material handling equipment (fork lift trucks, telehandlers, and lift gates). They are also used in heavy industry such as cranes, oil rigs, and above ground mining.

Piston Rod construction
The piston rod of a hydraulic cylinder operates both inside and outside the barrel, and consequently both in and out of the hydraulic fluid and surrounding atmosphere.

Metallic coatings
Smooth and hard surfaces are desirable on the outer diameter of the piston rod and slide rings for proper sealing. Corrosion resistance is also advantageous. A chromium layer may often be applied on the outer surfaces of these parts. However, chromium layers may be porous, thereby attracting moisture and eventually causing oxidation. In harsh marine environments, the steel is often treated with both a nickel layer and a chromium layer. Often 40 to 150 micrometer thick layers are applied. Sometimes solid stainless steel rods are used. High quality stainless steel such as AISI 316 may be used for low stress applications. Other stainless steels such as AISI 431 may also be used where there are higher stresses, but lower corrosion concerns.

Ceramic coatings
Due to shortcomings of metallic materials, ceramic coatings were developed. Initially ceramic protection schemes seemed ideal, but porosity was higher than projected. Recently the corrosion resistant semi ceramic Lunac 2+ coatings were introduced. These hard coatings are non porous and do not suffer from high brittleness.

Lengths
Piston rods are generally available in lengths which are cut to suit the application. As the common rods have a soft or mild steel core, their ends can be welded or machined for a screw thread.