omniomni/omni-engineering huggingface dataset:
Explorer S-56 (satellite). Explorer S-56 was a NASA satellite launched on 4 December 1960, at 21:14 GMT as part of the Explorer program. The satellite was composed of a  diameter inflatable sphere, and was intended to study the density of the upper atmosphere. The Scout X-1 rocket used to launch Explorer S-56 failed in flight, and the satellite never reached orbit.

Spacecraft design 
The spacecraft consisted of alternating layers of aluminium foil and Mylar polyester film. Uniformly distributed over the aluminium surface were -diameter dots of white paint for thermal control. The sphere was packed in a tube  in diameter and  long and mounted in the nose of the fourth stage of its Scout X-1 launch vehicle.

Upon separation of the fourth stage, the sphere will be inflated by a nitrogen gas bottle, and a separation spring will eject it out into its own orbit. The two hemispheres of aluminium foil will be separated with a gap of Mylar at the spacecraft's equator and will serve as the antenna. A 136 MHz, 15 mW beacon will be carried for tracking purposes, the beacon and the SAO Baker-Nunn camera network will be relied upon for tracking. Power will be supplied by solar cells and rechargeable batteries.

Launch 
Explorer S-56 was launched, at 21:14 GMT on 4 December 1960, from Launch Area 3 at the Wallops Flight Facility (WFF), atop a Scout X-1 launch vehicle with the serial number ST-3. It was the first attempt to place a satellite in orbit using an all-solid propellant launch vehicle and the first orbital attempt made from NASA's Wallops Island facility. It was the first spacecraft launched from Wallops Island, but failed to reach orbit due to the second stage not igniting and impacting in the Atlantic Ocean, at  at east of Wallops Island. It was replaced by the identical Explorer 9 (1961-004A) spacecraft.

The first of six identical air density research satellites to be launched.

See also 

 Explorer 9
 Explorer program

References 

Satellites of the United States
Explorers Program
Walter Blume. Walter Blume may refer to:

 Walter Blume (musician) (born in the 1880s; active 1910s–1930s), German kapellmeister, music critic, and scholar of Johannes Brahms
 Walter Blume (aircraft designer) (1896–1964), German fighter ace of World War I and aircraft designer
 Walter Blume (SS officer) (1906–1974), German Nazi SS-Standartenführer
List of aircraft at the Royal Air Force Museum Midlands. This list of aircraft at the Royal Air Force Museum Midlands summarises the collection of aircraft that is housed at the Royal Air Force Museum Midlands.

Collection

External display

Test Flight

War in the Air

National Cold War Exhibition

Hangar 1

Previously on display

See also
 Royal Air Force Museum London
 List of aircraft at the Royal Air Force Museum London

References

Aerospace museums in England
Royal Air Force Museum Cosford
Cosford
VFP-206. VFP-206 was a Light Photographic Squadron of the United States Navy Reserve established on 1 June 1970. The squadron was disestablished on 29 March 1987.

Operational history

1970's to Disestablishment
VFP-206 would be the last US Navy unit to operate the F-8 Crusader and was the last specialized photographic reconnaissance aircraft in Navy service. The last operational RF-8G #146860, was donated to the Smithsonian Institution on 30 March 1987, the day after VFP-206 was disestablished, it is now on display at the Steven F. Udvar-Hazy Center.

Home port assignments
NAF Washington

Aircraft assignment
RF-8G Crusader

See also
 Reconnaissance aircraft
 List of inactive United States Navy aircraft squadrons
 History of the United States Navy

References

External links

Fleet air reconnaissance squadrons of the United States Navy
Cisco IOS XE. IOS XE is a release train of Cisco Systems' widely deployed Internetworking Operating System (IOS), introduced with the ASR 1000 series.

It is built on Linux and provides a distributed software architecture that moves many operating system responsibilities out of the IOS process and has a copy of IOS running as a separate process. Since it runs a copy of IOS, all CLI commands are the same between Cisco IOS and IOS XE, in contrast to IOS XR, which has a completely different code base and whose developers implemented a different CLI command set.

Releases
IOS XE is released separately for ASR 1000 and Catalyst 3850.

Differences between IOS and IOS XE
Cisco IOS is a monolithic operating system running directly on the hardware while IOS XE is a combination of a Linux kernel and a monolithic application (IOSd) that runs on top of this kernel. On the other hand, IOS XR is based on QNX (since version 5.0 it's also based on Linux), where the IOSd application has been separated into many different applications. While IOS XE (IOSd) and IOS share a lot of the same code, IOS XR is a completely different code base.

Since IOS XE has IOSd running as an application on top of Linux, it becomes possible to also run different applications on the hardware, a good example of this is running Wireshark on a switch. Another example is the Cisco IOS XE Open Service Containers.

See also 
 Cisco NX-OS

References

External links
 Cisco Content Hub
 Cisco Feature Navigator
 

Cisco products
RoboValley. RoboValley is a centre for robotics, headquartered in Delft, Netherlands. RoboValley is powered by the Robotics Institute of Delft University of Technology. RoboValley aims to facilitate collaboration between researchers, governments and enterprises. Currently, RoboValley is looking to attract robotics companies and researchers in the field of robotics in order to facilitate this collaboration. Among others, TU Delft's Robotics Student Association is located in the centre.

The idea of RoboValley came from professor Martijn Wisse's vision of creating a Silicon Valley for robotics, which is how the name RoboValley came to be. Martijn Wisse soon presented his idea to Arie van den Ende, an entrepreneur and business developer.

Over the course of 2015, RoboValley continued its development, starting with the creation of the Robo Service Centre, a virtual office for start-up robotics companies and a shared service centre for all robotics activities in RoboValley. In September 2015, a delegation of RoboValley travelled to RoboBusiness in San Jose, California to officially present RoboValley to a worldwide audience.

On 31 May 2016, RoboValley and Chrysalix Venture Capital announced the launch of the RoboValley Investment Fund, raising 100 million Euro. The RoboValley Fund is intended to identify, invest in and commercialize new robotics technologies..

References

2015 establishments in the Netherlands
Robotics in the Netherlands
High Power User Equipment. High Power User Equipment (HPUE) is a special class of user equipment for the LTE cellular network.

In Release 11 of the LTE standard, 3GPP proposed so called High Power User Equipment (HPUE) for band 14 (700 MHz).

UE's outside of band 14 or 41 UE are only allowed to transmit at a maximum output power of 23 dBm, while on HPUE bands, they are allowed to transmit with an output power of up to 31 dBm. Since the transmission range depends on the transmit power, the cell range can be increased by nearly 80% and user devices can operate better in challenging RF environments, such as inside large concrete buildings.

The first HPUE was presented by the Finnish company Bittium Oyj formerly known as Elektrobit, together with Rohde & Schwarz at Mobile World Congress 2014. They implemented the test cases of 3GPP, to show that the use of HPUE does indeed not interfere with adjacent commercial LTE networks. Since then, HPUE has become much more commonplace and is available on a multitude of devices.

The first portable, battery-operated device to operate with HPUE capabilities in actual field operation is the HPUE Band 14 Personal Gateway device by Assured Wireless Corporation in early 2017. This device is fully compliant with 3GPP specifications for HPUE and operates at the full 31dBm maximum transmit power levels. Tests on networks around the U.S. and, specifically, actual public safety user experience at the 2017 Houston Livestock Show and Rodeo  showed the ability of this HPUE equipment to operate with any LTE Band 14 network with reliable performance that stays connected in areas where all existing standard-power LTE devices fail to connect, while also improving user data rates even in areas of good coverage and increasing overall cell capacity.

References

LTE (telecommunication)
Telecommunications equipment
Mohammed Rahif Hakmi. Mohammed Rahif Hakmi () is the founder and chairman of Armada Group, a UAE-based conglomerate.

Biography
Mohammed Rahif Hakmi is the founder and chairman of Armada Group and has been licensed by Dubai Land Department (RERA - Real Estate Regulatory Agency) as Developer back in 2008. Hakmi holds a degree in Civil Engineering, M.Phil. and a PhD in Structural Engineering from the University of Salford, United Kingdom.

In 1989, he was awarded a Ph.D. for his research into the Local Buckling of Sandwich Panels from the University of Salford in Manchester, England. He subsequently had been employed by the University of Salford where he conducted a series of research into numerical and experimental behaviour of materials, fire and blast  of Composite materials. Hakmi developed a design theory, one of his formula has been recommended by the CIB Working Commission W056 Sandwich Panels, ECCS/CIB Joint Committee to be used in codes of practice and has been adopted as design formula by the European recommendations for sandwich panels (CIB, 2000). He was also involved in the Marine-tech North West programme on cost-effective use of fibre reinforced composites offshore.

In 2008, he was appointed as the chairman of the Board of Honor of Al-Karamah SC Football Club in recognition of his support to the club.

Hakmi founded Armada in early 2000. He is its chairman. Under Hakmi the company has engaged in property development and other sectors, including hospitality and leisure, information technology and health care. Armada has developed some of Dubai's most notable landmarks, such as Armada Towers. The company has ongoing projects in Europe, Turkey and the Middle East.

Awards
 Science and Engineering Research Council Award, Overseas Research Scholarship (ORS) - United Kingdom.
 Institution of Structural Engineers Jubilee Award - United Kingdom.

See also
 Armada Group
 Al-Karamah SC
 Real Estate Regulatory Agency
 Armada Towers
 Sandwich plate system
 Metal faced insulating sandwich panels

References

External links
 Official website

1963 births
Businesspeople from Dubai
Living people
People associated with the University of Salford
People from Homs
AlphaCom. AlphaCom is a commercial SSH, Telnet and RS-232/modem client and terminal emulator by OmniCom Technologies. It is a Windows product but has been known to also run on Linux via emulation.

History
AlphaCom is a GUI-based RS-232/modem, Telnet and SSH client and terminal emulator. The earliest known version was released in 1999. It was previously part of a line of networking software which included a remote desktop client called winShadow, a Telnet server called AlphaServ, and a remote printing product called AlphaLPD. The company now offers only AlphaCom and AlphaLPD. All of the above are commercialware.

Features
 Wyse 50/50+, Wyse 60, SCO ANSI, Linux, IBM 3151, ANSI, VT220, VT102, VT100, VT52 emulations
 International keyboard and character set
 Built-in utilities includes file transfer, host look-up, ping, traceroute, FTP, time client and network scanner

OmniCom Technologies has further information on their web site.

Compatibility
AlphaCom runs on Windows XP, Windows Vista, Windows 7, Windows 8 and Windows 10. It also runs on the Windows Server series of operating systems. An experimental version for macOS was made available in January 2016.

Popularity
AlphaCom is a popular choice among system and network administrators.

 A free trial of AlphaCom is available. The trial version is valid for 30 days.

See also
 List of terminal emulators

References

External links
 AlphaCom product page at OmniCom Technologies

Telnet
Terminal emulators
Copper(I) thiocyanate. Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts.

Structure 
At least two polymorphs have been characterized by X-ray crystallography. They both feature copper(I) in a characteristic tetrahedral coordination geometry. The sulfur end of the SCN- ligand is triply bridging so that the coordination sphere for copper is CuS3N.

Synthesis 
Copper(I) thiocyanate forms from the spontaneous decomposition of black copper(II) thiocyanate, releasing thiocyanogen, especially when heated. It is also formed from copper(II) thiocyanate under water, releasing (among others) thiocyanic acid and the highly poisonous hydrogen cyanide. It is conveniently prepared from relatively dilute solutions of copper(II) in water, such as copper(II) sulphate. To a copper(II) solution sulphurous acid is added and then a soluble thiocyanate is added (preferably slowly, while stirring). Copper(I) thiocyanate is precipitated as a white powder. Alternatively, a thiosulfate solution may be used as a reducing agent.

Double salts 
Copper(I) thiocyanate forms one double salt with the group 1 elements, CsCu(SCN)2. The double salt only forms from concentrated solutions of CsSCN, into which CuSCN dissolves. From less concentrated solutions, solid CuSCN separates reflecting its low solubility. When brought together with potassium, sodium or barium thiocyanate, and brought to crystallisation by concentrating the solution, mixed salts will crystallise out. These are not considered true double salts. As with CsCu (SNC)2, copper(I) thiocyanate separates out when these mixed salts are redissolved or their solutions diluted.

Uses 
Copper(I) thiocyanate is a hole conductor, a semiconductor with a wide band gap (3.6 eV, therefore transparent to visible and near infrared light). It is used in photovoltaics in some third-generation cells as a hole transfer layer. It acts as a P-type semiconductor and as a solid-state electrolyte. It is often used in dye-sensitized solar cells. Its hole conductivity is however relatively poor (0.01 S·m−1). This can be improved by various treatments, e.g. exposure to gaseous chlorine or doping with (SCN)2.

CuSCN with NiO act synergically as a smoke suppressant additive in polyvinyl chloride (PVC).

CuSCN precipitated on carbon support can be used for conversion of aryl halides to aryl thiocyanates.

Copper thiocyanate is used in some anti-fouling paints. Advantages compared to cuprous oxide include that the compound is white and a more efficient biocide.

References 

Copper(I) compounds
Thiocyanates
Semiconductor materials
Coordination polymers
Boron carbides. Boron carbides are boron–carbon compounds.

Boron carbide (B4C)

B13C2

α-tetragonal boron
α-tetragonal boron is a boron-rich isotropic boron carbide (B50C2).

Borafullerenes

Borafullerenes are a class of heterofullerenes in which the element substituting for carbon is boron.

See also
 Crystal structure of boron-rich metal borides

References

Sources

 
 
 
 

Inorganic carbon compounds
Boron compounds
Map segmentation. In mathematics, the map segmentation problem is a kind of optimization problem. It involves a certain geographic region that has to be partitioned into smaller sub-regions in order to achieve a certain goal. Typical optimization objectives include:
 Minimizing the workload of a fleet of vehicles assigned to the sub-regions;
 Balancing the consumption of a resource, as in fair cake-cutting.
 Determining the optimal locations of supply depots;
 Maximizing the surveillance coverage.

Fair division of land has been an important issue since ancient times, e.g. in ancient Greece.

Notation 
There is a geographic region denoted by C ("cake").

A partition of C, denoted by X, is a list of disjoint subregions whose union is C:

There is a certain set of additional parameters (such as: obstacles, fixed points or probability density functions), denoted by P.

There is a real-valued function denoted by G ("goal") on the set of all partitions.

The map segmentation problem is to find:

where the minimization is on the set of all partitions of C.

Often, there are geometric shape constraints on the partitions, e.g., it may be required that each part be a convex set or a connected set or at least a measurable set.

Examples 
1. Red-blue partitioning: there is a set  of blue points and a set  of red points. Divide the plane into  regions such that each region contains approximately a fraction  of the blue points and  of the red points. Here:
 The cake C is the entire plane ;
 The parameters P are the two sets of points;
 The goal function G is
 
 It equals 0 if each region has exactly a fraction  of the points of each color.

Related problems 
 A Voronoi diagram is a specific type of map-segmentation problem.
 Fair cake-cutting, when the cake is two-dimensional, is another specific map-segmentation problem when the cake is two-dimensional, like in the Hill–Beck land division problem.
 The Stone–Tukey theorem is related to a specific map-segmentation problem.

References 

Fair division
Mathematical optimization
Unambiguous Turing machine. In theoretical computer science, a Turing machine is a theoretical machine that is used in thought experiments to examine the abilities and limitations of computers. An unambiguous Turing machine is a special kind of non-deterministic Turing machine, which, in some sense, is similar to a deterministic Turing machine.

Formal definition 
A non-deterministic Turing machine is represented formally by a 6-tuple,  , as explained in the page non-deterministic Turing machine.
An unambiguous Turing machine is a non-deterministic Turing machine such that, for every input , there exists at most one sequence of configurations  with the following conditions:
  is the initial configuration with input 
  is a successor of  and
  is an accepting configuration.
In other words, if  is accepted by , there is exactly one accepting computation.

Expressivity 

The language of an unambiguous Turing machine is defined to be the same language that is accepted by the nondeterministic Turing machine. A language of strings L can be defined to be unambiguously recognizable if it is recognizable by an unambiguous Turing machine.
The class of unambiguously recognizable languages is exactly the same as the class of recursively enumerable languages (RE).

In particular, every deterministic Turing machine is an unambiguous Turing machine, as for each input, there is exactly one computation possible.
Therefore, all recursively enumerable languages are unambiguously recognizable.

On the other hand, unambiguous non-deterministic polynomial time is suspected to be strictly less expressive than (potentially ambiguous) non-deterministic polynomial time.

References 
Lane A. Hemaspaandra and Jorg Rothe, Unambiguous Computation: Boolean Hierarchies and Sparse Turing-Complete Sets, SIAM J. Comput., 26(3), 634–653

Turing machine
Physical Review Accelerators and Beams. Physical Review Accelerators and Beams is a monthly peer-reviewed open-access scientific journal, published by the American Physical Society. The journal focuses on accelerator physics and engineering. Its lead editor is Frank Zimmermann (CERN). The journal was established in 1998 as Physical Review Special Topics – Accelerators and Beams, obtaining its current title in 2016. The journal does not require article processing charges, being sponsored by academic and industrial institutions.

Abstracting and indexing 
The journal is abstracted and indexed in:
Current Contents/Physical, Chemical & Earth Sciences
Inspec
Science Citation Index Expanded
Scopus
According to the Journal Citation Reports, the journal has a 2021 impact factor of 1.879.

References

External links

American Physical Society academic journals
Academic journals established in 1998
English-language journals
Monthly journals
Particle physics journals
Creative Commons Attribution-licensed journals
Bertha (drag boat). Bertha is a steam-powered boat built in 1844 to remove silt from the Port of Bridgwater in Somerset, England. It is the oldest operational steam vessel in Britain, and possibly in the world. It is part of the National Historic Fleet.

The boat was built, of riveted iron, in Bristol by Lunnel, G & Co copying a design, by John McLean, developed by Isambard Kingdom Brunel to deal with silt in the Floating Harbour. It is a bed leveler or plough dredger, with a large metal blade, which could be lowered at the stern of the boat, below the water similar to a bulldozer on land.

Bertha is  long and  wide, with a tonnage of 60 tons. The power is from a coal fired single cylinder steam engine providing steam at . A large flywheel and drive shaft drove a single-reduction spur wheel drive. It moved by being pulled along chains anchored on the quay.

Bertha worked in Bridgwater Docks, after the connection of the Bridgwater and Taunton Canal to the River Parrett, from 1844 until 1969. The vessel was initially owned by the Great Western Railway and then British Railways. She was then taken to the Exeter Maritime Museum, where she was shown working with the help of John Selby (welder and fabricator in Spaxton, Somerset). In 1997 it moved to the World of Boats at Eyemouth where it was restored. The Eyemouth Maritime Museum closed and Bertha is now in Bristol, but not on public display.

Notes 
1. It is unclear which type of ton is being referred to in the sources where a tonnage of 60 is reported. Gross register tonnage (GRT) represents the total internal volume of a vessel, where one register ton is equal to a volume of 100 cubic feet (2.83 m3)

References

Ships and vessels of the National Historic Fleet
Bridgwater
Ships designed by Isambard Kingdom Brunel
PathMinder. PathMinder is file manager software, or DOS shell originally designed for use under DOS disk operating systems. Published by Westlake Data Corporation of Austin, Texas, and designed by Albert Nurick and Brittain Fraley, it was first released on 30 September 1984 and became fairly popular. Although the user interface was composed of text characters, it had many graphical elements, especially when PathMinder Plus was released in 1989, and the Reconfigurable User Interface was introduced. 

PathMinder won numerous computer industry awards and product comparisons, and was nominated for PC Magazine's Technical Excellence award.

PathMinder was the first DOS shell to incorporate an integrated text editor, the first to include an application manager, and the first to include activity logging.

The program filled a required niche in the market, as DOS shipped with no graphical file manager, until the generally unsuccessful DOS Shell that was provided with MS-DOS 4. 

PathMinder had several key features which contributed to its success, including a virtual loader that required only 4 KB of RAM when other programs were running, an important feature when less than 640 KB of RAM were available on systems of the day.

A version of PathMinder was independently developed in 1988 to run on the CP/M operating system.

PathMinder suffered a terminal decline after the widespread usage of Microsoft Windows.  Westlake Data released a version of PathMinder designed for the Windows 3.1 operating system called PathMinder Does Windows, but it met with little critical or commercial success.

See also
 Comparison of file managers

References

External links
 InfoWorld Review
 Dabbling with DOS Directories
 Pathminder+ Utilities Include Crosstalk, Editor
 Arthur-PC

DOS software
File managers