omniomni/omni-engineering huggingface dataset:
Kolb Flyer. The Kolb Flyer is an American single seat, high wing, strut-braced, twin-engine, pusher configuration, conventional landing gear-equipped ultralight aircraft that was produced in kit form by Kolb Aircraft of Phoenixville, Pennsylvania, and intended for amateur construction.

The Flyer was the first design produced by Kolb Aircraft. Based on the Flyer's success, the company and its successor, New Kolb Aircraft, have gone on to produce over 3000 aircraft as of 2010.

Design and development
The Flyer was a very early ultralight design that first flew in 1970. The first aircraft designed by Homer Kolb, it was ahead of its time and was not produced commercially until 1980, when the ultralight boom hit North America.

The Flyer is a very light and simple aircraft with a standard empty weight of only . It features a completely open cockpit with the pilot exposed to the slipstream. Unusually for this period in aircraft history when most ultralights had two-axis control, the Flyer has standard three-axis controls, including half span ailerons.

When the Flyer was designed there were no suitable lightweight engines available, so the prototype aircraft first fitted Chrysler powerplants. Later these were exchanged for Solo 209 engines producing  each. The small Solo engines make the Flyer a very quiet aircraft in flight.

The design features a forward fuselage of welded 4130 steel tubing, mated to an aluminum tailboom. The horizontal stabilizer, tail fin and wings are also constructed of riveted aluminum tubing with all flying surfaces covered in doped aircraft fabric.

The conventional landing gear consists of sprung steel tubing for the main gear, with a sprung tail skid.

The Flyer was later improved and developed into a single engine aircraft, the Kolb Ultrastar, which succeeded it in production in 1982.

Specifications (Flyer)

See also

References

External links
Photos of Kolb Flyer

Flyer
1970s United States ultralight aircraft
High-wing aircraft
Aircraft first flown in 1970
Twin-engined piston aircraft
Aircraft with fixed conventional landing gear
Friedrich Seifert. Friedrich Alfred Seifert (born 8 May 1941) is a German mineralogist and geophysicist. He is the founding director of Bayerisches Geoinstitut at University of Bayreuth. A silicate mineral, seifertite, is named after him.

Life and work
Seifert was born in Dresden, Germany in 1941. He studied mineralogy at the University of Kiel and the University of Zurich and received his PhD degree from the University of Zurich in 1966 for his work on the rock metamorphosis at high temperatures and pressures. For his post-doctorate work, Seifert moved to University of Bochum and defended a habilitation thesis in 1970. In 1972, he became professor at the University of Bochum. He then stayed at the Carnegie Geophysical Laboratory in Washington, DC, where he applied Mössbauer spectroscopy to study the kinetics of the formation of rocks and minerals. After returning to Germany in 1974, he assumed a professor position at the University of Kiel. Seifert changed to the University of Bayreuth in 1986 and became the first director of the newly founded Bayerisches Geoinstitut at the university.

Awards and honors
Seifert is a member of several academic societies, including Academia Europaea (1990), German Academy of Sciences Leopoldina (1991), Göttingen Academy of Sciences (1992) and Bavarian Academy of Sciences and Humanities (2006). In 1987, he was awarded the Gottfried Wilhelm Leibniz Prize, worth 2.5 million euro. In 1994, he received an honorary doctorate from the Faculty of Science and Technology at Uppsala University, Sweden. In 2004, he received the Abraham Gottlob Werner Medal for achievements in the experimental and theoretical petrology and spectroscopy of minerals and silicate melts.

In 2008, a high-pressure polymorph of quartz (SiO2), seifertite, was named after Seifert. This mineral and its name are officially recognized by the International Mineralogical Association.

References

21st-century German geologists
German mineralogists
Gottfried Wilhelm Leibniz Prize winners
1941 births
Living people
German geophysicists
Members of Academia Europaea
20th-century German geologists
Signal Corps Dirigible No. 1. Signal Corps Dirigible No. 1 was the first powered aircraft ordered for the Signal Corps by the Aeronautical Division of the United States Army. The purchase of SC-1, a dirigible designed by Thomas Scott Baldwin, was the result of urgings by Chief Signal Officer Brigadier General James Allen. After seeing Baldwin demonstrate a dirigible at the St. Louis air meet in 1907, Allen had urged the U.S. Army to buy a dirigible, as many European armies had dirigibles by the turn of the century.

On 5 August 1908, the Army tested SC-1  at Fort Myer, Virginia. The craft fell short of a two-hour, 20 mph objective to meet a $8,000 per unit award. The Army formally accepted the craft as Signal Corps Dirigible No. 1, paying $5,737.50. On 28 August 1908 Lieutenants Frank Lahm, Michael "CC" Finney, Thomas Selfridge, and Benjamin Foulois were taught to fly the craft.

After Second Lieutenant John G Winter Jr of the 6th Cavalry was assigned to duty in the Aeronautical Division, the balloon detachment was transferred to Fort Omaha, Nebraska.

On 26 May, pilot Lieutenant Lahm and Lieutenant Foulois made a flight in SC-1 at Fort Omaha, and maneuvered the craft at will. SC-1 remained there until scrapped in 1912. The Army did not purchase another dirigible until after World War I.

Specifications (Signal Corps Dirigible No. 1)

References

Airships of the United States
1900s United States experimental aircraft
Baldwin aircraft
Pope Branch. Pope Branch is a tributary stream of the Anacostia River in Washington, DC, United States.  The headwaters of the stream originate near Fort Davis Drive, and the branch flows roughly northwest for about  to the Anacostia, which drains to the Potomac River and the Chesapeake Bay. The watershed area of Pope Branch is about .

Water quality issues
Pope Branch is in a highly urbanized area and the stream has been polluted by urban runoff (stormwater) and leaking sewer pipes. 

The District of Columbia Department of Energy and Environment has conducted stream restoration projects in Pope Branch Park. Regenerative stormwater conveyances were installed to capture runoff from adjacent streets. The restoration work is designed to reduce erosion and pollutant discharges to the stream.

The District of Columbia Water and Sewer Authority (DC Water) completed repairs on the sewer line in 2014. It began stream restoration in the sewer line area in January 2016 and the work was scheduled for completion in October 2016.

See also
List of District of Columbia rivers

References

External links
 Anacostia Watershed Society
 Anacostia Watershed Restoration Partnership

Anacostia River
Rivers of Washington, D.C.
Aichi AB-6. The Aichi AB-6, or Aichi Experimental 7-Shi Reconnaissance Seaplane, was a prototype Japanese reconnaissance floatplane. It was a single-engined, three-seat biplane intended for the Imperial Japanese Navy, but only one was built, the rival aircraft from Kawanishi, the E7K being preferred.

Design and development

In 1932, the Imperial Japanese Navy raised a specification for a long-range floatplane reconnaissance aircraft to replace its Yokosuka E1Y and E5Y operating from its seaplane tenders and  battleships, requesting prototypes from Aichi and Kawanishi.  Aichi's entry, the Aichi AB-6 or  Aichi Experimental 7-Shi Reconnaissance Seaplane, designed by Tetsuo Miki, was based on the Heinkel He 62, one example of which had been imported by Aichi the previous year for evaluation against a similar requirement.  The AB-6 was a biplane with folding wings for storage aboard ship, of all-metal construction with fabric covering, and powered by a single Hiro Type 91 W12 engine.  Its crew of three, pilot, observer and radio operator/gunner were accommodated in an enclosed cockpit.

Operational history

The prototype was completed in February 1933 and made its maiden flight from Nagoya harbor. While it had good handling in the air, its speed, take-off, and landing performance was disappointing, and the aircraft was modified to try to improve matters.  It was fitted with revised wings, of different aerofoil section and with full-span leading edge slats.  The original Hamilton-Standard two-bladed metal variable-pitch propeller was first replaced by a two-bladed wooden propeller and then a four-bladed wooden unit.  Despite these changes, Kawanishi's design remained superior, and in 1934, was ordered into production as the Navy Type 94 Reconnaissance Seaplane, or Kawanishi E7K.

Specifications (final configuration)

See also

Notes
 In the Japanese Navy designation system, specifications were given a Shi number based on the year of the Emperor's reign it was issued.  In this case 7-Shi stood for 1932, the 7th year of the Shōwa era.

References

Francillon, R.J. Japanese Aircraft of the Pacific War. London:Putnam, 1970. .
Mikesh, Robert and Shorzoe Abe. Japanese Aircraft 1910–1941. London:Putnam, 1990. .

1930s Japanese military reconnaissance aircraft
Floatplanes
AB-6
Biplanes
Single-engined tractor aircraft
Aircraft first flown in 1933
Melanophlogite. Melanophlogite (MEP) is a rare silicate mineral and a polymorph of silica (SiO2). It has a zeolite-like porous structure which results in relatively low and not well-defined values of its density and refractive index. Melanophlogite often overgrows crystals of sulfur or calcite and typically contains a few percent of organic and sulfur compounds. Darkening of organics in melanophlogite upon heating is a possible origin of its name, which comes from the Greek for "black" and "to be burned".

History
Melanophlogite was identified and named by Arnold von Lasaulx in 1876 although G. Alessi had described a very similar mineral as early as in 1827. The mineral had a cubic crystal structure; chemical analysis revealed that it is mainly composed of SiO2, but also contains up to 12% of carbon and sulfur. It was suggested that the decomposition of organic matter (carbon) in the mineral was responsible for its blackening upon heating. All studied samples originated from Sicily, and thus the mineral was called Girghenti, an old name for Agrigento town in Sicily. The name was officially changed to melanophlogite in 1927.

Synthesis and properties

Melanophlogite can be grown synthetically at low temperatures and elevated pressures (e.g. 160 °C and 60 bar). It has a zeolite-like porous structure composed of Si5O10 and Si6O12 rings. Its crystalline symmetry depends on the content of its voids: crystals with spherical guest molecules or atoms (e.g. CH4, Xe, Kr) are cubic and the symmetry lowers to tetragonal for non-spherical guests like tetrahydrofuran or tetrahydrothiophene. Since many molecules form unstable guests, the symmetry of melanophlogite can change between cubic and tetragonal upon mild heating (<100 °C).

Even the cubic melanophlogite often shows anisotropic optical properties. They were attributed not to tetragonal fragments but to the organic film in the mineral which could be removed by low-temperature annealing (~400 °C). Otherwise, melanophlogite is thermally stable and its physical properties do not change upon 20-day annealing at 800 °C, but it converts to cristobalite after heating at temperatures above 900 °C.

Occurrence

Melanophlogite is a rare mineral which usually forms round drops (see infobox) or complex intertwinned overgrowth structures over sulfur or calcite crystals. Rarely, it occurs as individual cubic crystallites a few millimeters in size. It is found in Parma, Torino, Caltanissetta and Livorno provinces of Italy; also in several mines of California in the US, in Crimea (Ukraine) and Pardubice Region (Czech Republic).

References

External links

Spectroscopic data on Melanophlogite
 - zeolite properties of melanophlogite

Silica polymorphs
Tahseen Ullah Khan. Tahseen Ullah Khan was a Pakistan Navy naval officer and served as director-general of the Pakistan Maritime Security Agency. A Navy engineer officer, Khan has previously served as a Defence Attaché at the Pakistan High Commission in Malaysia and as a military advisor to the Malaysian Navy.

Education
Khan attended the military high school Cadet College Kohat where he graduated with a pre-engineering advanced diploma. He is a graduate of Pakistan Navy Staff Course and Armed Forces War Course and holds degrees of B.Sc. (Hons) in Chemical engineering from Karachi University and Master's degree in War Studies from Quaid-e-Azam University, Islamabad. He also holds a diploma in French language from National University of Modern Languages, Islamabad.

Pakistan Navy career
Khan was commissioned in the Pakistan Navy on 1 December 1977. Upon attaining his commission, he was selected to undergo his training at Britannia Royal Naval College, Dartmouth, Devon, United Kingdom. On his return from UK, he joined the Submarine Service of the Pakistan Navy where-in he served onboard submarines in various capacities. He specialized in the Arms of Submarines from CIN, St. Mandrier, France in 1986. He also served as ADC to Chairman Joint Chiefs of Staff Committee from 1989–91.  He commanded two submarines; S-134 PNS Ghazi/M and S-133 PNS Mangro from 1994–96.

Defence attaché and military advisor
He served as Defence and Naval Advisor in Pakistan High Commission Kuala Lumpur (Malaysia) from 1996–1999.  On return, he was appointed at Naval Headquarters as Director Maritime Affairs and later as Director Submarine Operations.  He has also served as Deputy Director General Maritime Security Agency.  Upon his promotion to the rank of Commodore, he was appointed to the faculty of National Defence University, Islamabad in 2004 for two years from where he was appointed Commander North before being appointed as Commandant, PN War College, Lahore.

Before his appointment as Director General Maritime Security Agency, he was serving as Chief Staff Officer to Commander Pakistan Fleet. His interests include reading and relaxing by listening to music and golfing in leisure time. He is married and has a daughter and a son.

References

Living people
Year of birth missing (living people)
Pakistan Navy vice admirals
University of Karachi alumni
Pakistani military engineers
Pakistani naval attachés
Dependability state model. A dependability state diagram is a method for modelling a system as a Markov chain. It is used in reliability engineering for availability and reliability analysis.

It consists of creating a finite-state machine which represent the different
states a system may be in. Transitions between states happen as a result of events from underlying Poisson processes with different intensities.

Example 

A redundant computer system consist of identical two-compute nodes, which each fail with an intensity of . When failed, they are repaired one at the time by a single repairman with negative exponential distributed repair times with expectation .

 state 0: 0 failed units, normal state of the system.
 state 1: 1 failed unit, system operational.
 state 2: 2 failed units. system not operational.

Intensities from state 0 and state 1 are , since each compute node has a failure intensity of . Intensity from state 1 to state 2 is .
Transitions from state 2 to state 1 and state 1 to state 0 represent the repairs of the compute nodes and have the intensity , since only a single unit is repaired at the time.

Availability 

The asymptotic availability, i.e. availability over a long period, of the system is equal to the probability that the model is in state 1 or state 2. 

This is calculated by making a set of linear equations of the state transition and solving the linear system. 

The matrix is constructed with a row for each state. In a row, the intensity into the state is set in the column with the same index, with a negative term.

 

The identities cells balance the sum of their column to 0:

 

In addition the equality clause must be taken into account: 

By solving this equation, the probability of being in state 1 or state 2 can be found, which 
is equal to the long-term availability of the service.

Reliability 

The reliability of the system is found by making the failure states absorbing, i.e. removing all outgoing state transitions.

For this system the function is:

Criticism 

Finite state models of systems are subject to state explosion. To create
a realistic model of a system one ends up with a model with so many states that it is infeasible to solve or draw the model.

References 

Reliability engineering
Markov models
Graphical models
Berlin Mills Railway 7. Berlin Mills Railway 7 is a  steam locomotive at Steamtown National Historic Site in Scranton, Pennsylvania. It was built in 1911 by the Vulcan Iron Works for the Berlin Mills Railway, an industrial line in Berlin, New Hampshire. Number 7 worked there as a switcher until November 1944, when it was sold to the Groveton Papers Company of Groveton, New Hampshire. In 1956, it was finally replaced by a diesel locomotive, ending 45 years of use. After a few years of idleness, though, the locomotive was leased to the Woodsville, Blackmount and Haverhill Steam Railroad, a new tourist railroad near Haverhill. It operated as the only locomotive for this company until it folded after 1963.  It was ultimately donated to Steamtown by the Groveton Paper Company in 1969.

References 

Vulcan Iron Works locomotives
2-4-2ST locomotives
Preserved steam locomotives of Pennsylvania
Individual locomotives of the United States
Standard gauge locomotives of the United States
Railway locomotives introduced in 1911
Sakuragichō train fire. The  occurred on April 24, 1951, when a 63 series Keihin Line (now part of the Negishi Line) train approaching Sakuragichō Station in Yokohama hit a loose overhead wire causing a short circuit and starting a fire which killed 106 people and injured 92.

Accident
On the day in question, maintenance crews were renewing the electrical insulators of the overhead wires when at 1:38 PM a hanging wire (from which the contact wire is suspended) was accidentally cut allowing the contact wire to hang down. Four minutes later a 5-car MoHa 63 series train (1271B) approached from Yokohama Station and changed lines 50 metres before Sakuragichō but the pantograph of the leading carriage became tangled in the hanging contact wire. The driver attempted to lower the pantograph, but it fell sideways and hit the wooden carriage, causing sparks which started a fire on the roof which rapidly spread to the rest of the carriage.

The 150 people travelling in the carriage were unable to open the electrically operated doors. The connecting door to the second carriage only opened inwards, impossible with the crowd of panicking passengers inside. Finally, the windows of the carriage were too small to escape through: 63 series cars, of wartime design, employed many cost-cutting measures, one of which was a three-pane window design, where only lower and upper panes could be opened. Intended to escape an expense of a large, full-sized glass pane, this design left the openings too small to pass through. The passengers were therefore trapped; the first car, constructed soon after World War II of combustible materials (another cost-cutting measure was the wooden roof of these cars), was completely consumed by fire within ten minutes, killing 106 people and injuring 92 more.

Response
The investigation report resulted in improved fire-proofing of all such carriages and the provision of through-corridors between carriages. Although the electrically operated doors had manual overrides positioned under the passenger seats, this was poorly signed. The report resulted in their being marked with red signage.

This accident also caused the resignation of Hideo Shima, director of the railway's rolling stock department, in 1951. Shima was later employed with Japanese National Railways in 1955 to design and build Japan's first "bullet train" (Shinkansen).

A monument to the accident victims was subsequently built at Sōji-ji in Tsurumi-ku, Yokohama.

See also
List of transportation fires

References

Sources
Train Fire at Sakuragi-cho

1950s fires in Asia
1951 fires
Fires in Japan
Accidents and incidents involving Japanese National Railways
Railway accidents and incidents in Japan
Railway accidents in 1951
Train and rapid transit fires
History of Yokohama
Rail transport in Yokohama
1951 in Japan
April 1951 in Asia
1951 disasters in Japan
Vehicle fires in Asia
Intel Cluster Ready. The Intel Cluster Ready certification is a marketing program from Intel. It is aimed at hardware and software vendors in the low-end and mid-range cluster market. To get certified, systems have to fulfill a minimum set of cluster-specific requirements. This way, vendors of parallel software can build their applications on a basic cluster platform, trusting certain components to be present. Other drivers, libraries and tools will have to be provided by the software vendor or its partners, or by a system integrator.

Description 
The program was announced in June 2007.
The nodes of an Intel Cluster Ready compliant cluster are based on Xeon server processors and PC hardware, interconnected through Ethernet or InfiniBand. The operating system is a Linux distribution conforming to a specific file system layout. Also included are Intel's closed source but publicly available parallel libraries: the Message Passing Interface, Threading Building Blocks, and Math Kernel Library.

Intel only specifies the requirements a cluster has to fulfill to get certified. The specific implementation is the responsibility of the platform vendor. Intel's Cluster Checker checks the system's compliance. It is not only deployed by the vendor, the integrator and the end user to verify the system, it can also be used to troubleshoot an operational cluster.

While cluster hardware gets certified, software can be registered as well. Intel provides a minimal cluster infrastructure where software vendors can run their package, test scripts and test data. After successful completion, the application gets registered as being Intel Cluster Ready compliant. The Cluster Ready program is free for both hardware and software vendors.

The Intel Cluster Ready program does not primarily include the high-end clusters used for scientific calculations at universities and research institutes. It aims to commoditize the parallel systems used for industrial and commercial applications. According to IDC, more than half of the servers currently sold for technical applications is deployed as part of a cluster. For example, these systems are used for industrial computations, financial analyses, and modelling in engineering. IDC expects clustered systems to responsible for more than three-quarters of the high-performance technical computing market.

AMD-based clusters 
Although the Cluster Ready program is aimed at systems built on Intel's Xeon processors, the Cluster Checker can also be used to verify an Advanced Micro Devices-based system. Intel's parallel libraries run on AMD hardware with the same performance and are fully supported by Intel. According to Werner Krotz-Vogel, Technical Marketing Engineer at Intel's Cluster Ready team, the Math Kernel Library (MKL) runs even faster than the open source library Automatically Tuned Linear Algebra Software (ATLAS) on an AMD Opteron system.

References

External links 
http://www.intel.com/go/cluster

Intel