omniomni/omni-engineering huggingface dataset:
Modulation transformer. A modulation transformer is an audio-frequency transformer that forms a major part of most AM transmitters. The primary winding of a modulation transformer is fed by an audio amplifier that has about 1/2 of the rated input power of the transmitter's final amplifier stage. The secondary winding is in series with the power supply of that final radio-frequency amplifier stage, thereby allowing the audio signal to lower and raise the instantaneous DC supply voltage of the power amplifier (PA) tube or transistor. Considering that the PA device is operated as a class-C amplifier, i.e. as a switch, the modulation transformer is responsible for the amplitude modulation (AM) of the transmitter. There Is only one system of modulation that can be used without the modulation transformer with high power. "This is loop modulation"

Audio engineering
Roberts Cygnet. The Roberts Cygnet is an American high-wing, cruciform tail, single-seat, glider that was designed and produced by Donald Roberts as a contender for the IGC World Class sailplane.

Design and development
The Cygnet was the sole US entrant in the competition for the World Class sailplane, losing out to the Polish Politechnika Warszawska PW-5. As a result only one Cygnet was completed. The prototype was finished and first flown in 1992

The aircraft is made from steel tubing and aluminium, with fiberglass fairings. Its  span wing employs a Somers-Maughmer SM701 airfoil and features balanced top and bottom DFS-style air brakes for glidepath control. A ballistic parachute was to be standard equipment.

Operational history
In August 2011 the sole Cygnet built was still listed on the US Federal Aviation Administration registry.

Specifications (Cygnet)

See also

References

External links
Photo of the Cygnet

1990s United States sailplanes
Cruciform tail aircraft
Aircraft first flown in 1992
T-Engine Forum. T-Engine Forum was a non-profit organization which developed an open standard for real time embedded system development and developed ubiquitous computing environment. It maintained the open specification for ITRON Specification OS, and developed T-Kernel and ubiquitous ID architecture. The chair of T-Engine Forum was Dr. Ken Sakamura. T-Engine Forum was formed in 2002 and existed until its name was changed into TRON Forum in 2015.

History
In 1984 TRON Project was started by  Dr. Ken Sakamura of the University of Tokyo. The project's goal was to design an open real-time OS (RTOS) kernel(s). The TRON framework tries to define complete architecture for different computing application scenarios. For different scenarios, the need for different OS kernels was identified. (See, for example, papers written in English in TRON Project 1988)  ITRON specification OS for industrial applications became the most popular TRON RTOS. ITRON specification promotion was done by the various companies which sold the commercial implementations. The focus of these activities was a non-profit organization called TRON Association which acted as the communication hub for the parties concerned with the development of ITRON specification OS and its users in many fields including home electronics, smart house industry, etc.

In 2002, T-Engine Forum was formed to provide an open source RTOS implementation that supersedes the ITRON specification OS, and provides binary compatibility additionally. The new RTOS was  T-Kernel. The activities of TRON Association to support TRON Project  were taken over  by T-Engine Forum in 2010. 

In 2015, T-Engine Forum changed its name into  TRON Forum.

Organization
As of July 2011 there were 266 members in T-Engine Forum. Executive Committee members include Japanese companies such as Fujitsu, Hitachi, NTT DoCoMo and Denso. A-members were involved in the design and development of the specifications for T-Engine and T-Kernel, or of Ubiquitous ID technology. They  include companies such as NEC and Yamaha Corporation. B-members were involved in the development of products using T-Engine specification and T-Kernel. They include companies like ARM, Freescale, MIPS Technologies, Mitsubishi, Robert Bosch GmbH, Sony Corporation, Toshiba and Xilinx. The supporting members and academic members include many universities like the University of Tokyo, Japan and Dalian Maritime University, China.

As noted above, TRON Forum has overtaken the work which used to be done by former T-Engine Forum since 2015.

See also
TRON Project	
ITRON	
T-Kernel

References

External links 
 , TRON
 The Most Popular Operating System in the World
 Ken Sakamura
 ITRON Project Archive
 Introducing the μT-Kernel
 Information about T-Engine, T-Kernel and μT-Kernel Programming

TRON project
Standards organizations in Japan
Science and technology in Japan
Romney Duffey. Romney Beecher Duffey (born 1942, New Romney, Kent, England) is an American nuclear scientist. Duffey has worked on modern energy systems, in the areas of thermohydraulics, system design, system analysis, risk assessment, human factors, and technological safety in Britain, United States and Canada for about 40 years, and authored numerous publications, including several books.

Duffey is an ASME Fellow, former Chair of ASME Nuclear Engineering Division, former Chair of American Nuclear Society Thermal-Hydraulics Division, the Chief Scientist of Atomic Energy of Canada Limited, member of New York Academy of Sciences, member of American, Canadian and British Nuclear Associations. He served as advisor or program reviewer for numerous organizations, including NASA Ames, International Atomic Energy Agency, Natural Resources Canada, European Union, Generation IV International Forum, General Electric Corporation, Columbia University, StonyBrook University.

References

21st-century American physicists
Atomic Energy of Canada Limited
Alumni of the University of Exeter
Fellows of the American Society of Mechanical Engineers
Living people
1942 births
Lipscombite. Lipscombite (Fe2+,Mn2+)(Fe3+)2(PO4)2(OH)2 is a green gray, olive green, or black. phosphate-based mineral containing iron, manganese, and iron phosphate.

Lipscombite is often formed at meteorite impact sites where its crystals are microscopically small, because crystal-forming conditions of pressure and temperature are brief.

In the Classification of non-silicate minerals lipscombite is in the lipscombite group, which also includes zinclipscombite. This group is within the non-silicate, category 8, anhydrous phosphates, lazulite supergroup.

Discovery

The mineral lipscombite was first made artificially and then found in nature. It was named after chemist William Lipscomb by the mineralogist John W. Gruner who first made it artificially.

While investigating the stability relations of iron oxides small, black, shiny crystals were obtained when a spherical iron pressure-temperature vessel was contaminated with phosphorus.  The x-ray powder diffraction pattern was similar to lazulite, but unknown.

Gruner, a mineralogist at the University of Minnesota, gave Lipscomb, a chemistry professor there, the crystals for Lewis Katz and Lipscomb to determine the atomic structure using single-crystal x-ray diffraction.  They initially called the mineral iron lazulite.

References

External links

Gallery of lipscombite pictures at mindat.org.

Manganese(II) minerals
Phosphate minerals
Hydroxide minerals
Tetragonal minerals
Minerals in space group 96
Savage 1861 Navy. The Savage 1861 Navy was a cap and ball revolver manufactured by the Savage Revolving Firearms Company from 1861 to 1862. This company is unrelated to the later Savage Arms Company. It was used by both sides during the American Civil War.

Design
The Savage 1861 Navy is quite unique in appearance and is only comparable to its predecessor, the Savage 1859 Figure Eight. Both guns are recognized by its use of a kind of "proto double-action" with a second trigger underneath the first. When this trigger is pulled it rotates the cylinder and cocks the hammer.

History
Designed in 1860 by Henry S. North and Edward Savage, production began in Middletown, Connecticut in 1861 and ended in 1862 with a total of 20,000 units produced. An initial order of 5,500 units was placed in 1861 but was later extended to 12,000 units. The first units were delivered late 1861. The remaining units were sold to civilians and several ended up being used by the Confederates.

Use during the American Civil War

During the American Civil War the Savage 1861 Navy was officially used by the following United States army regiments: 1st Wisconsin U.S. Volunteer Cavalry, 2nd Wisconsin U.S. Volunteer Cavalry, 5th Kansas Volunteer Cavalry, and the 7th New York Cavalry.

Confederate States Army regiments: 34th Battalion of Virginia Cavalry, 35th Battalion of Virginia Cavalry, 11th Texas Cavalry, 7th Virginia Cavalry and the 7th Missouri Cavalry.

The United States Navy also used the revolver in small numbers, but it was never widely adopted due to a lack of consistency and low quality production material/machines. This amounted to a pistol that was more of a concept, being one of the only double triggered pistols in existence. The Savage Navy just couldn't compare to other models like the Colt Army 1860, and quickly became a high demand collectors item over an army pistol.

Post war use
Even though the gun was offered to the soldiers when the war ended, only 17 units were reported being bought.

References

External links
armscollectors.com
www.nramuseum.com
www.rebelstatescurrency.com
coolgunsite.com

American Civil War weapons
Revolvers of the United States
Weapons of the Confederate States of America
Double-action revolvers
Reconfigurable video coding. The Reconfigurable Video Coding (RVC) is an MPEG initiative to provide an innovative framework of video coding development. This framework offers a way to overcome the lack of interoperability between the many video codecs deployed in the market. Indeed, an RVC codec is described using the dataflow programming paradigm which permits flexibility and reusability. Two standards have been produced by the RVC working group:
 The codec configuration representation (ISO/IEC 23001-4 or MPEG-B pt. 4) describes the format with which an RVC decoder can be defined as a network of computational blocks, as well as a textual language for the definition of video coding blocks.
 A video tool library (ISO/IEC 23002-4 or MPEG-C pt. 4) that standardizes actors needed to describe existing video coding standards (currently MPEG-4 part 2 and MPEG-4 part 10).

Motivations
RVC was motivated by the following observations:
 In the last two decades, many video coding standards (MPEG-2, MPEG-4 AVC, VP8, etc.) have been specified to meet consumers' demands. These new technologies have been using increasingly complex algorithms and many of them share some common parts (a discrete cosine transform for example). Unfortunately, there was at the time no standard way to exploit these similarities.
 The specification of a video coding standard was previously provided with a textual document and reference software, without consideration for the effort needed to implement the standard on multi-core processors or hardware platforms.

History
Work on Reconfigurable Video Coding started in March 2004 during an MPEG meeting at Munich with the research of common elements among existing MPEG standards. After more than two years of work, it was found that even if their specifications were strictly different they had some very similar architectures and related data flow.
A Call for Proposals was made during the 76th MPEG meeting at Montreux, this call aimed to collect technologies to describe some unified descriptions of the MPEG video technology.
The next meeting saw the proposal to build a MPEG Reconfigurable Video Coding framework accepted, and work on the development of standard components started.

See also 
 Dataflow
 CAL Actor Language

External links
 ISO Standards 23001-4 and 23002-4
 Open RVC CAL Compiler

Video codecs
Image-based flow visualization. In scientific visualization, image-based flow visualization (or visualisation) is a computer modelling technique developed by Jarke van Wijk  to visualize two dimensional flows of liquids such as water and air, like the wind movement of a tornado. Compared with integration techniques it has the advantage of producing a whole image at every step, as the technique relies upon graphical computing methods for frame-by-frame capture of the model of advective transport of  a decaying dye. It is a method from the texture advection family.

Principle
The core idea is to create a noise texture on a regular grid and then bend this grid according to the flow (the vector field). The bent grid is then sampled at the original grid locations. Thus, the output is a version of the noise, that is displaced according to the flow.

The advantage of this approach is that it can be accelerated on modern graphics hardware, thus allowing for real-time or almost real-time simulation of 2D flow data. This is particularly handy if one wants to visualise multiple scaled versions of the vector field to first gain an overview and then concentrate on the details.

References

External links
 Website of Jarke van Wijk with demo software and pictures

Scientific visualization
Numerical function drawing
Fluid dynamics
Carveboarding. Carveboarding is a boardsport that takes place on hard surfaces such as roads and sidewalks. It combines elements of surfing, snowboarding, and skateboarding, providing a riding experience that resembles surfing and snowboarding.

The board used in carveboarding is equipped with small hinges that allow it to tilt up to approximately 45° relative to the horizontal position. This tilt capability, which is much greater than traditional skateboard trucks, enables more aggressive turns and reduces speed loss during carving. Unlike skateboarding, carveboarding/surfskating allows riders to accelerate without needing to push a foot against the ground (commonly known as tic-tac in skateboarding), keeping the front wheels off the ground.

The ability to quickly change edges (rail to rail) allows riders to generate speed through flexion and extension, similar to "shortboard" surfing and snowboarding. This carving effect helps develop the necessary skills for progressing in surfing and snowboarding.

Carveboarding aims to replicate the sensations of surfing, much like skateboarding did in its early stages. It also shares similarities with certain styles of snowboarding, given the historical connection between the two sports. Unlike the freebord and T-board, which were specifically designed to emulate snowboarding on a skateboard-like platform, the carveboard was developed by surfers/snowboarders, David Colley and Brad Gerlach, for surfers/snowboarders.

See also 
 Surfskating

References 

Surf culture
Boardsports
Staatsmijn Hendrik. The Dutch State Mine (DSM) Hendrik, in Dutch Staatsmijn Hendrik,  was a coal mine located in Brunssum. It was run by the Dutch state through its company DSM. The mine was in operation from 1915 until 1963, when it was integrated with DSM Emma. DSM Hendrik was named after Queen Wilhelmina's husband Henry of Mecklenburg-Schwerin.

The mine had four shafts. Shaft number 3 was a ventilation shaft on the Brunssummerheide near Nieuwenhagen. Shaft number 4 was the deepest at . Total production was 61.2 megatons of gas-rich coal that was used to produce coke.

NATO headquarters 
In 1967 when the mine was closed, the buildings were used to house the headquarters of the Allied Forces Central Europe (AFCENT). In 2012 this changed into the Allied Joint Force Command Brunssum, which still uses the site in 2023. Its facilities include a tax-free shop, a film theatre and sports facilities. Additional services are provided by the AAFES on US Army Garrison Brunssum.

References 

Coal mines in the Netherlands
Buildings and structures in Limburg (Netherlands)
Brunssum
Amber (processor). The Amber processor core is an ARM architecture-compatible 32-bit reduced instruction set computing (RISC) processor. It is open source, hosted on the OpenCores website, and is part of a movement to develop a library of open source hardware projects.

Overview
The Amber core is fully compatible with the ARMv2a instruction set and is thus supported by the GNU toolchain. This older version of the ARM instruction set is supported because it is not covered by patents, and so can be implemented with no license from ARM Holdings, unlike some prior open source projects (e.g., nnARM).  The cores were developed in Verilog 2001 and are optimized for field-programmable gate array (FPGA) synthesis. For example, there is no reset logic: all registers are reset as part of FPGA initialization.  The Amber project provides a complete embedded field-programmable gate array (FPGA) system incorporating the Amber core and several peripherals, including universal asynchronous receiver/transmitters (UARTs), timers, and an Ethernet MAC.

The Amber project provides two versions of the core.  Both cores implement the same instruction set architecture (ISA) and are fully software compatible.

 The Amber 23 has a 3-stage pipeline, a unified instruction and data cache, a Wishbone interface, and is capable of 0.75 DMIPS (Dhrystone) per MHz. The Amber 23 core is a very small 32-bit core that performs well.  Register-based instructions execute in one cycle, except for those involving multiplication. Load and store instructions require three cycles. The core's pipeline is stalled either when a cache miss occurs, or when the core performs a Wishbone access.
 The Amber 25 has a 5-stage pipeline, separate data and instruction caches, a Wishbone interface, and is capable of 1.0 DMIPS per MHz. The Amber 25 core provides 30 to 40% better performance than the Amber 23 core and is 30 to 40% larger. Register-based instructions execute in one cycle, except for instructions involving multiplication, or complex shift operations. Load and store instructions also execute in one cycle unless there is a register conflict with a following instruction. The core's pipeline is stalled when a cache miss occurs in either cache, when an instruction conflict is detected, when a complex shift is executed, or when the core performs a Wishbone access.

Both cores have been verified by booting a Linux 2.4 kernel. Versions of the Linux kernel from the 2.4 branch and earlier contain configurations for the supported ISA. Versions of the Linux kernel 2.6 and later do not explicitly support the ARM v2a ISA and so need more modifications to run. The cores do not contain a memory management unit (MMU) so they can only run a non-virtual memory variant of Linux, such as μClinux.

See also
 Acorn Computers

Further reading
For a description of the ARMv2a ISA, see Archimedes Operating System: A Dabhand Guide, or Acorn RISC Machine Family Data Manual.

References

External links
 
 Amber Core Specification
 Marsohod Blog
 

Open microprocessors
Embedded microprocessors
Soft microprocessors
The Chilling Stars. The Chilling Stars is a non-fiction book about the possible causes and effects of global climate change by Henrik Svensmark and Nigel Calder. The paperback version was published by Totem Books on March 19, 2003. An updated version titled The Chilling Stars: A New Theory of Climate Change was published in 2007. Svensmark is otherwise known as a Danish physicist and professor, while Calder had worked as a science journalist.

The authors argue that cloud cover changes caused by variations in cosmic rays are a major contributor to global temperature increases, and they state that human influences have been exaggerated.

Contents and background

The authors describe a cross-disciplinary theory that takes in elements of cosmology, particle physics, paleo-climatology, and meteorology. They label their concept 'cosmoclimatology', and they attempt to look back through prior climate trends such as the Medieval Warm Period and the Little Ice Age. They detail what they view as a close correlation between the rate of cosmic rays reaching the Earth, which varies based on electromagnetic fluctuation on the Sun's surface, and the Earth's temperature.

They write how the solar magnetic field grew over twice as strong as before over the 20th century, and they peg this as a primary driver of the approximately 0.6 °C warming over that time. Specifically, they state that fewer cosmic rays cause fewer clouds to form, and thus the climate becomes hotter, given that the individual water droplets that make up clouds collect when cosmic particles turn water into ions.

Reviews

The online magazine londonbookreview.com remarked, "For those who believe that the argument about the causes of climate change have been settled may find this a difficult book to read. But those who retain an open mind may find this an interesting read, even if it is only to confirm that the science is far from being settled."

Scientists have generally not found the published work of Svensmark et al. persuasive. For example, Lockwood et al. find that "The cloud-cosmic ray suggestion increasingly fails to match observations". A joint Spanish/Japanese collaboration of solar ray/astrophysics experts found that the change in global cloud cover is closely correlated with El Niño–Southern Oscillation and uncorrelated with solar rays.

See also
 Scientific opinion on climate change
 The Great Global Warming Swindle
 The Cloud Mystery

References

External links
Book Excerpt from news.bbc.co.uk

Climate change books
2003 non-fiction books
2003 in the environment
2007 in the environment
Environmental non-fiction books
Guillotine test. In safety engineering, a Guillotine Test simulates an arc fault condition between parallel conductors or a cut wire, replicating the conditions that result from arc faults and which can lead to fires in adjacent material and wires, for example during accidents. Based upon a dry arc test method used for testing wire insulation material, this test was originally developed for arc-fault circuit interrupters. Here is a sample test schematic, showing the logic flow of one guillotine test. It shows the guidelines on whether to retest or if the test was passed or failed.

Testing of this type plays an important role in helping researchers who are looking into wiring faults in aircraft, submarine communication cables, etc. This can lead to products that are able to quickly identify and locate these wiring faults for easier and less costly repairs and an overall safer environment.

See also
 Arc fault
 Arc-fault circuit interrupter

References 

Safety engineering