omniomni/omni-engineering huggingface dataset:
German submarine U-745. German submarine U-745 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II, and which was lost at sea on 31 January 1945.

U-745 was launched on 16 April 1943, under the command of Oberleutnant zur See Wilhelm von Trotha, who would remain its commanding officer for its entire service. U-745 had a crew of 45.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-745 had a displacement of  when at the surface and  while submerged. She had a total length of , a pressure hull length of , a beam of , a height of , and a draught of . The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of  for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of  for use while submerged. She had two shafts and two  propellers. The boat was capable of operating at depths of up to .

The submarine had a maximum surface speed of  and a maximum submerged speed of . When submerged, the boat could operate for  at ; when surfaced, she could travel  at . U-745 was fitted with five  torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one  SK C/35 naval gun, 220 rounds, and two twin  C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.

Service history
She undertook four patrols during her service, and sank one allied auxiliary ship, the Soviet minesweeping trawler T-45 Antikajnen (No. 48), and one allied warship, the Soviet fleet minesweeper T-76 Korall.

Fate
On 31 January 1945, she was lost with all hands in the Gulf of Finland by a mine laid by the Finnish minelayers  and  on 12 January 1945.

Wilhelm von Trotha's body was later found near Föglö, Finland, and was buried three days later. No other bodies were recovered. Unlike most U-boats, which suffered casualties during the course of service due to accidents or other causes, U-745 suffered no casualties at all, until the time of her disappearance.

In late 2012 the Finnish diving team 'Badewanne', after 10 years of searching, reported they had found both  and U-745 in the Gulf of Finland south of Hanko.

Summary of raiding history

References

Notes

Citations

Bibliography

External links

World War II submarines of Germany
German Type VIIC submarines
U-boats sunk in 1945
1943 ships
Ships built in Danzig
U-boats commissioned in 1943
World War II shipwrecks in the Baltic Sea
Shipwrecks in the Gulf of Finland
Ships built by Schichau
U-boats sunk by mines
Submarines lost with all hands
U-boat accidents
List of Hawker Tempest operators. The List of Hawker Tempest operators lists the counties and their air force units that have operated the aircraft:

Operators

Canada
Royal Canadian Air Force
Only one Hawker Tempest was ever operated by the RCAF. The aircraft was in service from 1946 to 1947.

Nazi Germany
One Mk.5 (EJ709) was salvaged by 2./Versuchsverband O.K.L. after getting shot down in October 1944 and ferried to Finow for repairs. It was repaired with parts of another Tempest which was shot down at Thiene near Hesepe on 29 December 1944.

India
Indian Air Force

No. 1 Squadron, Indian Air Force
No. 3 Squadron, Indian Air Force
No. 4 Squadron, Indian Air Force
No. 7 Squadron, Indian Air Force
No. 8 Squadron, Indian Air Force
No. 9 Squadron, Indian Air Force
No. 10 Squadron, Indian Air Force

New Zealand

Royal New Zealand Air Force
No. 486 Squadron RNZAF

Pakistan 
Royal Pakistan Air Force
 No. 5 Squadron Falcons
 No. 9 Squadron Griffins
No. 14 Squadron Tail Choppers

Inherited 16 Tempest Mk.IIs from the British Indian Air Force instead of the original 35 fighters in 1947.

United Kingdom
Royal Air Force
No. 3 Squadron RAF
No. 5 Squadron RAF
No. 6 Squadron RAF
No. 8 Squadron RAF
No. 16 Squadron RAF
No. 20 Squadron RAF
No. 23 Squadron RAF
No. 26 Squadron RAF
No. 30 Squadron RAF
No. 33 Squadron RAF
No. 39 Squadron RAF
No. 54 Squadron RAF
No. 56 Squadron RAF
No. 80 Squadron RAF
No. 152 Squadron RAF
No. 174 Squadron RAF
No. 181 Squadron RAF
No. 182 Squadron RAF
No. 183 Squadron RAF
No. 213 Squadron RAF
No. 222 Squadron RAF
No. 247 Squadron RAF
No. 249 Squadron RAF
No. 266 Squadron RAF
No. 274 Squadron RAF
No. 287 Squadron RAF
No. 349 Squadron RAF
No. 501 Squadron RAF

See also
Hawker Tempest

References

Hawker Tempest
Tempest
Hawker aircraft
Lasso Logic. Lasso Logic was a company formed in 2003 that pioneered continuous data protection (CDP) and an onsite–offsite backup technology for the small and medium enterprise market (SME). It was based in San Francisco.

Lasso Logic was the first company to provide a disk-based continuous data protection appliance, called Lasso CDP, which continually backed up servers, applications, PCs, and laptops to itself in real time. This allowed users who lost files to go back to various useful points in time. More recent backups were saved at more frequent intervals, but as backup versions receded in time, some of those versions were dropped by way of a complex algorithm which preserved theoretically more useful versions. Thus a user could always find a version to return to from the inception of backup, from minutes ago to years ago. Before Lasso Logic, the only backup options were single point in time (SPIT) snapshot software that allowed IT administrators to back up to tape or to disk, usually at a resolution of once a day.  The value proposition of the company was "set it and forget it" backup, thus eliminating the labor burden of tape-based backup.

The company was also the first to introduce onsite and offsite backup in a single device.  Lasso CDP continuously backed up data to itself, but then replicated data to an offsite location. This allowed for instant recovery of data because the files were stored locally on the Lasso CDP appliance.  However, in the event of a total loss of data locally, including the Lasso CDP appliance, the customer could pull the data back from Lasso's offsite data center.

Lasso Logic and another company, enKoo, were acquired by SonicWALL in November 2005 for approximately $20 million total.  Lasso Logic became the third of three business divisions at SonicWALL, and called the Business Continuity Unit. Lasso CDP was renamed to SonicWALL CDP. The founders of Lasso Logic became the founding team behind PacketTrap Networks, a network management software company located in Silicon Valley.

References

 Business Week, Karen E. Klein, April 2005. "Have You Backed Up Your Data Today?"
 InfoWorld, Sean McCown, Jan, 2006, "Lasso Logic offers real easy real-time" backups"
 Byte and Switch, "Lasso Logic Unveils CDP Appliance, Lasso Logic ships end-to-end CDP solution for SMB and remote office protection"
 

Computer companies established in 2003
2003 establishments in California
American companies established in 2003
American companies disestablished in 2005
2005 mergers and acquisitions
Computer companies disestablished in 2005
2005 disestablishments in California
DKW F89. The DKW Meisterklasse (English: "Master Class"), also known as the DKW F89, is a compact front-wheel drive saloon manufactured by Auto Union GmbH between 1950 and 1954. It was the first passenger car to be manufactured by the new Auto Union company in West Germany following the re-establishment of the business in the west in 1949.

The Factory
Apart from the former DKW factory at Berlin-Spandau, the Auto Union’s manufacturing plants had been located in Saxony at Zwickau, Chemnitz and Zschopau when war had put an end to passenger vehicle production in 1942. After the war the company was no longer able to access its production facilities in the Soviet occupation zone. The first post war DKWs were therefore built under contract in a refurbished plant by Rheinmetall-Borsig in Düsseldorf.

The Origins
The F89 shared its underpinnings with the DKW F8 / 'Meisterklasse' which had been available between 1939 and 1942, but the F89 has a steel body based on that of the DKW F9, a prototype which would have directly replaced the F8 on the Zwickau production lines had the war not intervened. Although many of the machine tools at that plant were crated up and shipped to the Soviet Union in 1945, Zwickau’s new controllers also built their own version of the DKW F9 prototype, and indeed the eastern version was put into production as the IFA F9, probably shortly before the Düsseldorf built F89.

The F89 was not the first vehicle built by Auto Union after the war. That honor goes to the DKW F89 L “Schnelllaster”, Rapid Transporter in English, a curiously modern light van built on the same chassis and using the same engine / transmission package, introduced in 1949.

The Body 
The form of the saloon’s body closely followed that of the prewar DKW F9. However, extensive ‘streamlining’ had been applied to the earlier design, and impressive claims were made for the F89’s lowered wind resistance.

In 1951 a two-seater hardtop coupe version, built by coach builders Hebmüller of Wuppertal became available, and the range was completed in October 1951 with the addition of a three-door estate version, employing a body conversion that made extensive use of timber, which was replaced in March 1953 by an all-steel body. The F89 estate, like its steel bodied, successors, was branded as the ‘Universal’.

Technical
The F89 featured a two-cylinder two-stroke engine of 684 cc with a stated output, at launch, of 23 bhp. A maximum speed of 100 km/h (62 mph) was claimed for the saloon (95 km/h / 59 mph for the 'Universal' estate). The engine was water-cooled, but there was no water pump. Cooling was by a convection-based  thermosiphon system. The front wheels were connected to the engine by means of a three-speed manual gear box controlled via a dash-board mounted Krückstockschaltung lever similar to that familiar to later generations from its application in the Citroën 2CV and Renault 4. Towards the end of the production run a four-speed manual box was offered on the Meisterklasse.

Data

See also
DKW Schnellaster

Sources and further reading

F89
Compact cars
Front-wheel-drive vehicles
Cars introduced in 1950
4,4'-Difluorobenzophenone. 4,4’-Difluorobenzophenone is an organic compound with the formula of (FC6H4)2CO.  This colorless solid is commonly used as a precursor to PEEK, or polyetherether ketone, a so-called high performance polymer.  Because PEEK is resistant to attack, it is commonly used in carbon fiber coatings and cable insulation.

Synthesis
4,4’-Difluorobenzophenone is prepared by the acylation of fluorobenzene with p-fluorobenzoyl chloride. The conversion is typically conducted in the presence of an aluminium chloride catalyst in a petroleum ether solvent.
FC6H4C(O)Cl + C6H5F → (FC6H4)2CO + HCl

Uses
The polymer PEEK is generated from the reaction of 4,4'-difluorobenzophenone with the salts of 1,4-benzenediol.
C6H4(ONa)2  +  (FC6H4)2CO   →  1/n[(C6H4O2)(C13H8O)]n  +  2 NaF

References

4-Fluorophenyl compounds
Benzophenones
Modeling Maturity Levels. Modeling Maturity Levels is a classification system defined by Anneke Kleppe and Jos Warmer in their book MDA Explained (published by Addison-Wesley). The levels characterize the role of modeling in a software project.

The concept shows resemblance to the way software processes are rated with the Capability Maturity Model.

There are 6 levels:
Level 0 No Specification: the specification of software is not written down. It is kept in the minds of the developers
Level 1 Textual Specification: the software is specified by a natural language text (be it English or Chinese or something else), written down in one or more documents
Level 2 Text with Models: a textual specification is enhanced with several models to show some of the main structures of the system
Level 3 Models with Text: the specification of software is written down in one or more models. In addition to these models, natural language text is used to explain details, the background, and the motivation of the models, but the core of the specifications lies in the models.
Level 4 Precise Models: the specification of the software is written down in one or more models. Natural language can still be used to explain the background and motivation of the models, but it takes on the same role as comments in source code.
Level 5 Models only: the models are precise and detailed enough to allow complete code generation. The code generators at this level have become as trustworthy as compilers, therefore no developer needs to even look at the generated code.

References
T. Mettler, Thinking in terms of design decisions when developing maturity models, International Journal of Strategic Decision Sciences, 1(4), 2010, pp. 76-87.
T. Mettler, P. Rohner, and R. Winter, Towards a Classification of Maturity Models in Information Systems, Management of the Interconnected World, in: A. D'Atri, M. De Marco, A.M. Braccini, and F. Cabiddu (Eds.), Berlin, Heidelberg: Physica, 2010, pp. 333-340.
Anneke Kleppe and Jos Warmer in their book MDA Explained Addison-Wesley
Book:   MDA Explained: The Model Driven Architecture : Practice and Promise" by Anneke G. Kleppe, Jos B. Warmer, Wim Bast, Publisher: Addison-Wesley Professional,  Release Date: April 2003,

External links
Getting Started with Modeling Maturity Levels

Unified Modeling Language
Maturity models
Android 207. Android 207 (2006) is a short stop motion-animated film. It was directed, produced, written and edited by Canadian filmmaker Paul Whittington.

Premise
A robot with human-like features finds himself in a vast labyrinth full of traps. As it tries to escape, it must face emotional and psychological challenges.

Release and awards
The film was first released in the United States at the Milwaukee Short Film Festival on 4 June 2006. On 28 September 2006 it was released in Canada at the Vancouver International Film Festival. In 2007, the film received the Best Film, Best Technical and People's Choice awards at the Vancouver Island Short Film Festival. It went on to be shown at international film festivals in Beloit, Arizona and Milwaukee.

References

External links

Canadian black-and-white films
Stop-motion animated short films
2006 films
Canadian animated short films
2006 animated short films
Films about androids
2000s English-language films
2000s Canadian animated films
English-language short films
Dynamic compaction. Dynamic compaction is a method that is used to increase the density of soils when certain subsurface constraints make other methods of soil compaction inappropriate. The process involves dropping a heavy weight repeatedly on the ground at regularly spaced points, usually laid out in a systematic fashion such as a grid. The weight and the height from which it is dropped determine the force delivered to the ground surface and thus the amount of compaction that occurs. Depending on the degree of compaction desired, the weight may vary between , and the height between .

The impact of the free fall creates stress waves that help in the densification of the soil. These stress waves can penetrate up to . In cohesionless soils, these waves create liquefaction that is followed by the compaction of the soil; in cohesive soils, they create an increased amount of pore water pressure that is followed by the compaction of the soil. Pore water pressure is the pressure of water that is trapped in the spaces between the solid particles of rocks and soils.

The degree of compaction depends on the weight of the hammer, the height from which the hammer is dropped, and the spacing of the locations at which the hammer is dropped. The initial weight dropping has the most impact, and penetrates up to a greater depth. The following drops, if spaced closer to one another, compact the shallower layers and the process is completed by compacting the soil at the surface.

Most soil types can be improved with dynamic compaction. Old fills and granular soils are most often treated. The soils that are below the water table have to be treated carefully to permit emission of the excess pore water pressure that is created when the weight is dropped onto the surface.

References
Dynamic Compaction. U.S. Department of Transportation. Washington, DC: Federal Highway Administration, 1995.

Soil improvers
Sikorsky S-434. The Sikorsky S-434 is a light, turbine-powered helicopter. The S-434 is an improved development of the Schweizer S333.

Design and development
The prototype S-434 first flew on 18 December 2008 at Horseheads, New York. The S-434 evolved from the S-333, and has many features developed for the MQ-8 Fire Scout. It shares its cockpit layout with the S-333, which gives the crew very good visual capacities and handling characteristics.

On June 15, 2009, Sikorsky announced the delivery of the first two S-434s to Saudi Arabia's Ministry of the Interior, the first of a total of nine.

Variants
S-434  based on improvements developed for the MQ-8B; powered by one Rolls-Royce 250-C20W turboshaft engine of 320 shp.

Operators

 Ministry of the Interior

Specifications (S-434)

See also

References

External links

2000s United States helicopters
2000s United States civil utility aircraft
S-434
Single-turbine helicopters
Aircraft first flown in 2008
Single-rotor helicopters
Aircraft with skid landing gear
Methylrhenium trioxide. Methylrhenium trioxide, also known as methyltrioxorhenium(VII), is an organometallic compound with the formula . It is a volatile, colourless solid that has been used as a catalyst in some laboratory experiments. In this compound, rhenium has a tetrahedral coordination geometry with one methyl and three oxo ligands. The oxidation state of rhenium is +7.

Synthesis
Methylrhenium trioxide is commercially available. It can be prepared by many routes, a typical method is the reaction of rhenium heptoxide and tetramethyltin:

Analogous alkyl and aryl derivatives are known. Compounds of the type  are Lewis acids, forming both 1:1 and 1:2 adducts with halides and amines.

Uses
Methylrhenium trioxide serves as a heterogeneous catalyst for a variety of transformations. Supported on alumina/silica, it catalyzes olefin metathesis at 25 °C.

In solution, methylrhenium trioxide catalyses for the oxidations with hydrogen peroxide. Terminal alkynes yield the corresponding carboxylic acid or ester, internal alkynes yield diketones, and alkenes give epoxides. Methylrhenium trioxide also catalyses the conversion of aldehydes and diazoalkanes into an alkene, and the oxidation of amines to N-oxides with sodium percarbonate.

References

Organorhenium compounds
Methyl complexes
Bruno (software). BRUNO was the first commercial computer software program for creating presentations (Presentation program) using a WYSIWYG user interface.  BRUNO, which originated on the Hewlett Packard HP 1000 F-Series computer, was developed by Jim Long and Philip Walden of Hewlett Packard. The application was finished in 1979 and was used around the world by HP customers.  BRUNO was later ported to the HP-3000 and renamed HP-Draw.

Trivia 

 Bruno was named after a hand puppet used to train field sales representatives.
 Bruno became HP-Draw mostly because Robert Dea, a HP-3000 team member, and Philip Walden shared work topics during their long van pool rides.

References

Presentation software
Dufaux triplane. The so-called Dufaux triplane was an unnamed experimental aircraft built in Switzerland in 1908. It was constructed by the brothers Armand and Henri Dufaux who had previously experimented with a model helicopter. This new aircraft incorporated a feature far ahead of its time; the concept of a tiltrotor. Based on what they had learned from their helicopter, the Dufaux brothers hoped to generate vertical as well as horizontal thrust from their engine installation, and conceived of an aircraft where the engine and propeller would be mounted at the centre of the airframe and would be able to pivot 180° to provide forward, upward, and even backward thrust (the latter to assist in braking). Experiments with a boxkite fitted with an engine in 1905 proved promising, so construction of a full-scale aircraft proceeded.

The resulting machine featured two sets of triplane wings in tandem with the engine installation between them, followed by a biplane tail unit with a span almost equal to that of the wings. There was no fin, but all eight flying surfaces had a marked dihedral, and the fuselage was open framework. A large and heavy aircraft for its day, it immediately posed a problem to the brothers in trying to find a field large enough to test it in, since relying on forward thrust alone, the take-off distance was estimated at 300 metres (1,000 ft). Eventually, they settled on a cavalry training field at Bière,  from their workshop in Geneva. The aircraft was relocated there in July 1909, and tests proceeded through the summer. Problems plagued the trials, and on no occasion did the aircraft appear to come close to leaving the ground. In August, it was badly damaged when it toppled sideways while taxiing, and although repaired, the Dufaux brothers abandoned the project at the end of the month.

Specifications

References
 
 
 Geneva aviation pioneers

1900s Swiss experimental aircraft
Triplane
Tiltrotor aircraft
Triplanes
Unflown aircraft
Single-engined piston aircraft
Shadow memory. In computing, shadow memory is a technique used to track and store information on computer memory used by a program during its execution. Shadow memory consists of shadow bytes that map to individual bits or one or more bytes in main memory. These shadow bytes are typically invisible to the original program and are used to record information about the original piece of data.

Technique
The technique is utilized by memory-error checkers that can store information on which parts of memory have been allocated to the program being checked. This shadow memory is then used for detecting and reporting incorrect accesses of memory, even though the program may not be crashing due to a segmentation fault or similar. An error checker may also store additional information on memory such as which bits have been defined and which ones do not. Memcheck, part of the Valgrind suite, uses this to detect undefined behavior resulting from acting on or printing undefined memory values.

Use of shadow memory is however not limited to memory-error checkers, as what information is stored in these shadow bytes is not fixed. It is for instance used by ThreadSanitizer, a data race detector.

Shadow memory can be both implemented and used a lot of different ways, and have different performance characteristics. Memcheck for instance tracks values with bit precision, while AddressSanitizer, part of the clang compiler, is comparatively very fast. Memcheck, like all Valgrind tools, uses binary translation and instrumentation to run code manipulating the shadow memory corresponding to program memory use. AddressSanitizer on the other hand is created on compile-time and inserts error-checking code inline into a program during compilation. Its shadow-memory implementation uses a huge reservation of virtual memory for its shadow memory, giving very different performance characteristics.

References

General

 http://research.google.com/pubs/pub37752.html

Memory management