omniomni/omni-engineering huggingface dataset:
Urea nitrate. Urea nitrate is a fertilizer-based high explosive that has been used in improvised explosive devices in Afghanistan, Pakistan, Iraq, and various terrorist acts elsewhere in the world such as in the 1993 World Trade Center bombings.  It has a destructive power similar to better-known ammonium nitrate explosives, with a velocity of detonation between  and . It has chemical formula of  or . 

Urea nitrate is produced in one step by reaction of urea with nitric acid.  This is an exothermic reaction, so steps must be taken to control the temperature.

It was discovered in 1797 by William Cruickshank, inventor of the Chloralkali process.

Urea nitrate explosions may be initiated using a blasting cap.

Chemistry
Urea contains a carbonyl group. The more electronegative oxygen atom pulls electrons away from the carbon atom, forming a polar bond with greater electron density around the oxygen atom, giving it a partial negative charge. In a simplistic sense, nitric acid dissociates in aqueous solution into protons (hydrogen cations) and nitrate anions. The electrophilic proton contributed by the acid is attracted to the negatively charged oxygen atom on the urea molecule and the two form a covalent bond. The formed O-H bond is stabilized into a hydroxyl group when the oxygen abstracts an electron pair away from the central carbon atom, which leads to bond resonance between it and the two amino groups. As such, the urea cation can be thought of as a amidinium species. Paired with the spectator nitrate counteranion, it forms urea nitrate.

The compound is favored by many amateur explosive enthusiasts as a principal explosive for use in larger charges. In this role it acts as a substitute for ammonium nitrate based explosives. This is due to the ease of acquiring the materials necessary to synthesize it, and its greater sensitivity to initiation compared to ammonium nitrate based explosives.

References

Further reading

External links

Explosive chemicals
Nitrates
Ureas
Michael R. Fine. Michael R. Fine (born November 29, 1966) is a beta testing consultant, author, and inventor. He is the author of "Beta Testing for Better Software" (Wiley, 2002), and is a founder of and currently a senior test manager at Centercode, a beta testing software and services company. Fine is actively engaged in the promotion of beta testing as a concept, speaking  on the topic, teaching courses, and authoring  several articles on it.

Fine conducted beta tests on the first Palm handheld devices, as well as the original Bluetooth designs, and was significantly involved in the launch of xDSL and WiFi. He was also actively engaged in the testing of new modem standards, starting with V.32 up through V.92. Prior to helping found Centercode, Fine was the beta test manager for Megahertz, U.S. Robotics, and ultimately, 3Com Corporation. He was responsible for managing the beta testing of 3Com's networking and communications products for three of their global divisions.

In addition to technical writing for Iomega and several magazine articles, Fine is the author of three books:

 Beta Testing for Better Software ()
 Utah: The Complete Ski and Snowboard Guide ()
 Canoeing and Kayaking Utah ()

Fine contributed to U.S. Patent 6215799 for an ISDN analog interface, and U.S. Patent 6275933 for a security design.

Fine's experience in quality assurance, beta testing, alpha testing, and delta testing has him teaching courses on these subjects for LinkedIn Learning.

Fine graduated from Loyola Academy in 1984, then Weber State University in 1989, and currently serves as a member of its Alumni Association Board. Fine is a member of the Pi Kappa Alpha national fraternity.

References 

1966 births
American computer scientists
Living people
Software testing people
Weber State University alumni
Surfware. Surfware, Inc. is a Camarillo, CA-based company involved in the development of CAD/CAM software.

Company history
In 1950, Victor Diehl opened a mold shop in Southern California for machine tooling medical products. Throughout the 1950s, Victor Diehl focused on precision mold products for the medical industry. In the 1960s, Victor and Alan Diehl got a numerical control machine (CNC) to expedite tooling of components for aircraft manufacturing. Ten years later, Alan and his brother-in-law Jack Epps, a physicist, built a smart NC machine powered by a mini-computer.

In 1980, Bryan and Larry Diehl, joined the machining firm and wrote a UNIX program for surface modeling and machining. In 1988, Surfware, Inc. was formed by Alan and Larry, and SURFCAM was launched—a PC-based modeling and NC programming software to be offered to the CAD/CAM industry.

Over the next decade, SURFCAM's features advanced along with the capabilities of the PC. Started with NURBS surface technology on a PC, PC-based four-axis machining, CAM system for 32-bit architectures, PC CAM system with automatic rendering of blended surfaces, 2- and 3-axis rest machining.

In 2002, Surfware began work on what would become the TrueMill technology, a completely new toolpath strategy that controls the load on the tool to significantly increase CNC productivity extending also tool life for all materials, including aluminum, steels, titanium, Inconel and other exotics. SURFCAM Velocity Powered by Truemill was launched in 2005, this CAD/CAM software limits the maximum stepover to cut optimally everywhere along the toolpath on any part geometry. A patent (US 7,451,013) has been granted to Surfware.Inc for its “Engagement Milling” technology (TrueMill).

Surfware headquarters in Thousand Oaks, California. It maintains its own suite of milling machines to test the latest developments and innovations in the state-of-the-art TrueMill technology.

In 2013 Surfcam was acquired by Vero Software

In 2014 Vero Software was acquired by Hexagon

Release history

References

External links
 Surfware.Inc and Arkansas State University

Computer-aided manufacturing software
Companies based in Ventura County, California
Elliott Museum. The Elliott Museum, located at 825 N.E. Ocean Blvd. on Hutchinson Island in Stuart, Florida, United States, focuses on art, history, and technology. Named after the prolific inventor Sterling Elliott, the museum features a changing exhibition gallery and an art studio; maritime, baseball, and local history galleries; and bicycles, classic wooden boats, motorcycles, over 90 cars and trucks, and even an airplane. Over 50 vehicles are displayed in a unique robotic racking system which retrieves vehicles on demand for display on a turntable. The Elliott Museum has one of the largest collections of historic Ford Model A and Model AA commercial vehicles in the world.

History

The original Elliott Museum was built in 1961 by Harmon Elliott as a tribute to his father, Sterling Elliott.  On November 18, 1961, it was given to the non-profit Historical Society of Martin County, which has operated both the Museum and Gilbert’s Bar House of Refuge ever since. Some of the collection came from Sterling Elliott. Much of it was purchased by Harmon Elliott from an Americana Museum in Salem, Massachusetts for display in the Elliott Museum.

Over the years, the original building was in need of repair and the spaces no longer met the needs of the growing museum organization, so in June 2011 the original Elliott Museum building was torn down. The new, 48,000 square foot Elliott Museum opened to the public in March, 2013. The Museum opened with the donation of the Model A and Model AA commercial vehicle collection assembled by Elliott R. Donnelley. Shortly after opening, the Museum merged with the Classic Boat and Maritime Museum, taking on its collection of classic boats, boat models, and its mission of interpreting local maritime history.

The new Elliott Museum offers permanent and changing exhibitions, and the Museum hosts a number of programs and lectures throughout the course of the year. The Museum attracts a number of vintage car enthusiasts, and its annual car show Classics at the Beach has been held each Spring since 1996.

Footnotes

External links
 Museum website

Automobile museums in Florida
Sports museums in Florida
Technology museums in Florida
Biographical museums in Florida
History museums in Florida
Historical society museums in Florida
Museums in Martin County, Florida
Art museums and galleries established in 1961
1961 establishments in Florida
Stuart, Florida
Ofeq-7. Ofeq-7 (also known as Ofek 7 or Offek-7) is part of the Ofeq family of Earth observation satellites designed and built by Israel Aerospace Industries (IAI) for the Israel Ministry of Defense.

Launch 
The Ofeq-7 was launched by a Shavit 2 space launch vehicle on 10 June 2007 at 23:40 UTC. Equipped with advanced technology and a series of new enhancements to provide improved imagery, it is placed into an elliptical orbit of .

Mission 
Three days after its launch, on 13 June 2007, IAI MBT Space Division received the first images taken by the satellite. The Ofeq-7 is a follow-on spacecraft to Ofeq-5 that was placed into orbit in 2002.

References 

Reconnaissance satellites of Israel
Spacecraft launched in 2007
Spacecraft launched by Shavit rockets
2007 in Israel
Israel Aerospace Industries satellites
5th Space Launch Squadron. The United States Space Force's 5th Space Launch Squadron is a space launch unit located at Patrick Space Force Base, Florida. The 5th SLS is tasked with launch and support of the National Security Space Launch, Evolved Expendable Launch Vehicles.

History
The 5th Space Launch Squadron was activated on 14 April 1994 at Cape Canaveral Space Force Station, Florida as part of the Space Launch Delta 45, previously 45th Space Wing.  The squadron conducted Titan IV booster launch operations, launching classified military payloads into orbit until it was inactivated in June 1998.

The squadron was reactivated on 1 December 2003, and provides launch site mission assurance for all National Security Space Launch mission and has supervised assembly, testing and launch of commercial space boosters from Cape Canaveral since then.

Lineage
 Constituted as the 5th Space Launch Squadron on 29 March 1994
 Activated on 14 April 1994
 Inactivated on 29 June 1998
 Activated on 1 December 2003

Assignments
 45th Operations Group, 14 April 1994 – 29 June 1998
 45th Launch Group, 1 December 2003 – present
 Space Launch Delta 45, - present

Stations
 Cape Canaveral Air Force Station, Florida, 14 April 1994 – 29 June 1998
 Cape Canaveral Space Force Station, Florida, 1 December 2003 – present

Launch vehicles
 Titan IV, 1994-1998
 Delta IV, 2003-present
 Atlas V, 2003-present
 Falcon 9
 Falcon Heavy
 Vulcan

List of commanders

Lt Col David Schill, June 2021 - present

References

Bibliography

Squadrons of the United States Space Force
Military units and formations in Florida
Military units and formations established in 1994
John Tu. John Tu (; born August 12, 1941) is a Taiwanese-American billionaire businessman and philanthropist. He is the co-founder of Kingston Technology.

Early life
John Tu was born in Chongqing, China in 1941. He was the son of an official in China's Nationalist government. He moved to Shanghai with his parents in 1945, before going to Taiwan two years later as the Chinese Civil War neared the coast. 

Tu moved in 1960 to West Germany to study electrical engineering, and was educated at a language school in Munich. In Germany at that time, a two-year apprenticeship was required for everyone, so he worked at a shipbuilding factory. After working there for two years, he studied electrical engineering at the Department of Electrical Engineering and Information Technology of the Technische Hochschule Darmstadt in Germany and graduated in 1970. He then went to work for Motorola in Wiesbaden, Germany. In 1971 he moved to California.

Career
In 1982, he co-founded Camintonn with David Sun. In 1986, they sold it for $6 million. They then lost most their money in the 1987 stock market crash and founded Kingston Technology later that same year. In 1996, they sold 80 percent of the company to Softbank for $1.5 billion, before buying it back in 1999 for $450 million.

Philanthropy
In 2021 Tu made a donation to the Western Iowa Journalism Foundation that enabled the Pulitzer Prize-winning Storm Lake (Iowa) Times to buy its local competition and a weekly in an adjoining county. He has supported Erin Gruwell's Freedom Writers and the Freedom Writers Foundation. In 2011, he donated $1.2 million to give every first year medical student at UC Irvine an iPad.

Personal life
He is married with two children.

References

Living people
American billionaires
American computer businesspeople
American electrical engineers
American philanthropists
Chinese emigrants to the United States
Businesspeople from California
People from Rolling Hills, California
Businesspeople from Chongqing
1941 births
Technische Universität Darmstadt alumni
Chinese expatriates in Germany
SISC. SISC is an R5RS Scheme implementation, which includes a full number tower, hygienic macros, proper tail recursion, and first class continuations. SISC is short for Second Interpreter of Scheme Code, in reference to its predecessor LISC, the Lightweight Interpreter of Scheme Code.

SISC is free software, dual-licensed under the Mozilla Public License and the GNU General Public License, Version 2. It was developed by Scott G. Miller and Matthias Radestock.

Features
SISC depends on Sun Microsystems' Java programming language platform. This runtime environment allows SISC to provide many extensions and libraries such as networking, exception handling, a module system, and a Java foreign function interface.

The SISC website claims that it performs faster than any other Scheme interpreter based on the Java Virtual Machine (JVM).

Like GNU Guile, this Scheme is suitable for embedding into larger programs, where Guile is designed for inclusion in C programs, SISC is designed for the JVM.

References

Scheme (programming language) implementations
Scheme (programming language) interpreters
JVM programming languages
Software using the Mozilla Public License
PIK-26. PIK-26 Mini-Sytky is a low-wing monoplane, conventional landing gear aircraft. Designed by the Finnish aircraft designer Kai Mellen. Its high performance allows it to cruise at 173 km/h while burning 7 litres/hour. 
Several aircraft of this design are now flying.

The PIK-26 is mainly constructed from wood. While the skins are made of birch plywood, and the spars of pine, the wing ribs and some fuselage ribs are made of PVC foam. Construction time for the PIK-26 is about 2,300 hours.

Specifications (PIK-26 Mini-Sytky)

References

External links
Pik-26, Built by Paul Issaly
Pik-26, Panu Kääriäinen
Pik-26, Built by Janne
Pik-26 Construction Forum

Homebuilt aircraft
PIK aircraft
Aircraft first flown in 1996
Low-wing aircraft
Single-engined tractor aircraft
Astrobase. Johnny Astro Base was a toy made by the Ideal company in the early 1960s. The toy ran on 4 D Cell batteries. Besides a power switch, it had several features that includes the following modes of operation:

Modes of operation
 Astro Scope: Switch to Astro Scope and a scene of spaceships, rockets, and jets rotates through a viewfinder just below a radar dome on the top of the toy. A button on the console let the user "fire" at objects seen on the screen, which would pause the rotating images and emit a machine-gun style sound.
 Space Lock: A crane emerges from the hatch on one side of the toy. This crane has a hoist operation that can be used to raise or lower a plastic astronaut figure, or other objects that the user may have that can be connected to the hook at the end of a chain. The main purpose of this crane is to insert or remove the astronaut from a scout car.
 Scout Car: The scout car can be plugged into a port on the console and controlled by a two position switch marked "turn" and "drive" that can actually be used to steer the vehicle with a bit of practice. The scout car also has missiles that can be launched.

Ideal made two variations of the Astro Base. The original "all red" version featured a lighted Astro Scope that illuminated the pictures spinning around the Astro Scope. Ideal Toys discontinued this version and offered the common "red and white" version.

References

External links
 Astro Base

1960s toys
Motion diagram. A motion diagram represents the motion of an object by displaying its location at various equally spaced times on the same diagram. Motion diagrams are a pictorial description of an object's motion. They show an object's position and velocity initially, and present several spots in the center of the diagram. These spots reveal whether or not the object has accelerated or decelerated.

For simplicity, the object is represented by a simple shape, such as a filled circle. It contains information about object positions at particular time instances. Therefore, a motion diagram is more informative than a path.

Viewing motion diagrams
One of the major usages of motion diagrams is to present film through a series of frames taken by a camera. Viewing an object on a motion diagram allows one to determine if an object is at a constant rest, speeding up, or slowing down. As the frames are taken, it can be assumed that an object is at a constant rest if it occupies the same position over time. It can be assumed that an object is speeding up if there is a visible increase in the space between objects as time
passes. An object can be assumed to be slowing down if there is a visible decrease in the space between objects as time passes. The objects on the frame come very close together.

References
Bonham, Scott. (unknown year). Motion diagrams. Manuscript
submitted for publication, Department of Physics, Western Kentucky
University, Bowling Green, KY. Retrieved from
http://webphysics.davidson.edu/physlet_resources/western_kentucky/MotionDiagrams.html

Diagrams
China Railways BJ. The Beijing (), mostly referred to as BJ, is a diesel-hydraulic locomotive used in the People's Republic of China. It is named after the capital city of China, Beijing.

BJ were made in two different versions, a standard version and a kou'an (port) version. , a diesel electric locomotive based on DF7B, has a similar appearance to the Beijing locomotive.

North Korea

From 2002 the Korean State Railway has received a number of BJ class locomotives second-hand from China. They are used mostly for heavy shunting and on local freight trains around P'yŏngyang. At least 33 have been delivered, numbered in the 내연301 - 내연333 series (내연 = Naeyŏn, "internal combustion"); most are still painted in their original Chinese blue livery, but a few have been repainted into the standard North Korean scheme of light blue over dark green, and at least one, 내연310, is painted in a scheme identical to the Chinese green livery used on Chinese DF4 locomotives.

Gallery

References

BJ
Locomotives of North Korea
B-B locomotives
Standard gauge locomotives of China
Standard gauge locomotives of North Korea
Railway locomotives introduced in 1970
Rapid Attack Identification Detection Reporting System. The Rapid Attack Identification Detection Reporting System, also known as RAIDRS is a ground-based space control system that provides near real-time event detection.

Mission
RAIDRS will be a family of systems being designed to detect, report, identify, locate, and classify attacks against military space assets. RAIDRS will include detection sensors, information processors, and a reporting architecture. The RAIDRS system will detect and report attacks on both ground and space-based elements of operational space systems. It will notify operators and users, and carry information to decision-makers

Block 10
 Worldwide network of sensors; Centralized management
 Detect, Identify, Characterize SATCOM EMI interference
 Identify signal characteristics
 Geo-locate SATCOM EMI (Electro-Magnetic Interference)
 Report interference on blue space systems and/or services

Block 20
 Commander's decision support tool that provides Defensive Counterspace (DCS) attack assessment
 Integrates and processes critical Space Situation Awareness (SSA) information to provide the integrated space picture that enables DCS operations
 Multi-level distributed data fusion; Advanced visualization

Contract Information

The RAIDRS system is unique in the acquisitions process for being tailored to small businesses and utilizing commercial off-the-shelf (COTS) hardware and software.

According to the Air Force budget, the service intends to spend about $16 million in 2005 on the RAIDRS program; $16.4 million in 2006; $12.1 million in 2007; $12.4 million in 2008; and $66.6 million in 2009.

Contractor:
Kratos Defense & Security Solutions

Locations
 Peterson AFB, Colorado (2007–present) (Central Operating Location)

References

 16th Space Control Squadron
 380th Space Control Squadron

External links
 21st Space Wing Factsheet: 16th Space Control Squadron
 "U.S. Air Force System to Pinpoint Interference Sources", Space News 15 Nov 2004
 Air War College: Space Acquisition Projects
 "New squadron activates at Peterson", 21st Space Wing Public Affairs, 21 May 2007
 Space and Missile Systems Center: Transforming Military Space, 30 Nov 2006
 DefenseTech.org: "Pentagon's Plans for Space Control", 26 Jan 2007

Military space program of the United States
Equipment of the United States Air Force