omniomni/omni-engineering huggingface dataset:
SoloTrek XFV. The SoloTrek XFV (Exo-skeletal Flying Vehicle) was a single-person VTOL aircraft. It was first flown in December 2001 by Millennium Jet Inc, a private company run by Michael Moshier. Millennium Jet subsequently changed its name to Trek Aerospace Inc.  The SoloTrek pilot maintained a standing position and was propelled by two ducted fans located above and on either side of the user, leading some to class it as a type of backpack helicopter. It ran for around 2 hours on gasoline fuel. According to Michael Moshier, its inventor and designer, SoloTrek was capable of hovering for up to two hours, flying at 100 km/h and travelling more than 200 km.

One such model is featured in the 2003 movie Agent Cody Banks, though it is shown to be 'flying' only by the use of special effects. Early renderings of the SoloTrek were produced by Marc Ericksen, a Silicon Valley commercial artist and illustrator. Michael Moshier had commissioned Mark Ericksen to produce these renderings to help the company raise funding for the aircraft's development. Subsequently, the company was successful in receiving over $5 million of development funding from DARPA.

SoloTrek remains an extremely unusual design; to apply the name 'jet pack' is incorrect; the pilot was strapped into the exoskeleton frame which took the weight of the machine whilst landed, though it performed the same aim. In numerous trials at Trek Aerospace's facilities in Sunnyvale, California, the machine "appeared to perform perfectly".

During early flights, for safety reasons, the SoloTrek was 'tethered' to a crane during test flights, to prevent uncontrolled ascent or travel. The tethers were designed to retract during lift-off to avoid being sucked into the exposed ducted fans at the top of the machine, but during a flight shortly after a rain shower in December 2002, the tether failed to retract and became tangled in the propeller blades, which disintegrated. Pilot and machine dropped to the ground. The pilot walked away unharmed. Unable to stick to the tight development schedule that its backers demanded, Trek Aerospace lost funding, forcing reorganization in 2003.

After reorganization, Trek Aerospace extensively redesigned the aircraft, creating the Springtail EFV.  This machine first flew in October 2003, and went on to successfully complete its DARPA contract in 2005.

Trek Aerospace continues to develop ducted fan vehicles.

The original SoloTrek XFV is on display at the Hiller Aviation Museum in San Carlos, California.

See also
 Martin Jetpack
 Backpack helicopter
 NASA Puffin

References

External links
SoloTrek XFV
Ducted Rotor Test
http://www.unrealaircraft.com/qbranch/solotrek_xfv.php
http://www.trekaero.com/

VTOL aircraft
Trek Aerospace aircraft
Ducted fan-powered aircraft
2000s United States experimental aircraft
Atollo. ATOLLO is a construction toy invented by Scottish architect Donald Macdonald consisting of hinge and socket pieces.

Information
Its appeal lies in the flexibility of the three-dimensional shapes it can create. Atollo is sold by Tomy. It is also somewhat compatible with other construction products, such as LEGO or Uberstix. It was distributed throughout the world throughout the years of 1993-2003. It won awards such as the Dr. Toy Award and Parents Choice Award. The toy was developed and designed by architect Donald Macdonald and Euan Macdonald. The toy is recommended for children ages five and up.  It is possible that some of the pieces from Atollo can unintentionally get stuck together, but Atollo has created a tool that can separate them without breaking any pieces.

Kits
The kits that were available for purchase include:
Basic Starter Kit: a24-includes two colors and 24 pieces
Beginners Kit: a48-includes four colors and 48 pieces
a120 Kit- includes four colors and 120 pieces 
a240 Kit-includes four colors and 240 pieces

References

External links
ATOLLO

Takara Tomy
The India-Pakistan Air War of 1965. The India-Pakistan Air War of 1965 is a 2005 aviation history book written by PVS Jagan Mohan and Samir Chopra. The book deals with the Indian Air Force's role in the Indo-Pakistani War of 1965 that started on 1 September 1965 and came to an end on 23 September 1965.

Background
The air war was one of the last in which classic turning dogfights took place between the two belligerents. The Pakistan Air Force employed largely American hardware. The North American F-86 Sabre, the Lockheed F-104 Starfighter and the Martin B-57 Canberra (based on the British aircraft the English Electric Canberra). The Indian Air Force employed British, French & Russian aircraft like the Hawker Hunter, Folland Gnat, Canberra, de Havilland Vampire, MiG-21 and Dassault Mystere 

The book describes the day-to-day operations of the Indian Air Force and is the first detailed account of the airwar from the Indian side.

Reviews
Some reviews of the Book are available on the authors' web site  at BharatRakshak.com.
Review on Frontier India Journal

Further reading
The Class of '65 – Excerpts from Indian Express by Rakesh Sinha and Shiv Aroor
On a wing and a prayer – Excerpt from Rediff.com
The Wolfpack in action – Excerpt from Rediff.com

Aerial operations and battles of the Indo-Pakistani wars
2005 non-fiction books
Indo-Pakistani war of 1965
History of the Indian Air Force
Diazald. Diazald (N-methyl-N-nitroso-p-toluenesulfonamide) is used as a relatively safe and easily handled precursor to diazomethane, which is toxic and unstable. Diazald has become the favored commercially available precursor for the synthesis of diazomethane, compared to reagents like N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine, which are less thermally stable and more toxic and mutagenic, respectively.

Upon the addition of a base such as sodium hydroxide or potassium hydroxide and mild heating (65–70 °C) in a mixture of water, diethyl ether, and a high boiling polar cosolvent (e.g., diethylene glycol monomethyl ether), the N-nitrososulfonamide undergoes successive elimination reactions to produce diazomethane (which is codistilled as an ethereal solution) as well as a p-toluenesulfonate salt as a byproduct, according to the following mechanism:
Like other nitroso compounds, it is thermally sensitive, as a result of its weak N–NO bond whose bond dissociation energy was measured to be 33.4 kcal/mol.

References

Sulfonamides
Nitroso compounds
Alkyl-substituted benzenes
St-connectivity. In computer science, st-connectivity or STCON is a decision problem asking, for vertices s and t in a directed graph, if t is reachable from s.

Formally, the decision problem is given by
.

Complexity 
On a sequential computer, st-connectivity can easily be solved in linear time by either depth-first search or breadth-first search. The interest in this problem in computational complexity concerns its complexity with respect to more limited forms of computation. For instance, the complexity class of problems that can be solved by a non-deterministic Turing machine using only a logarithmic amount of memory is called NL. The st-connectivity problem can be shown to be in NL, as a non-deterministic Turing machine can guess the next node of the path, while the only information which has to be stored is the total length of the path and which node is  currently under consideration. The algorithm terminates if either the target node t is reached, or the length of the path so far exceeds n, the number of nodes in the graph.

The complement of st-connectivity, known as st-non-connectivity, is also in the class NL, since NL = coNL by the Immerman–Szelepcsényi theorem.

In particular, the problem of st-connectivity is actually NL-complete, that is, every problem in the class NL is reducible to connectivity under a log-space reduction. This remains true for the stronger case of first-order reductions . The log-space reduction from any language in NL to STCON proceeds as follows: Consider the non-deterministic log-space Turing machine M that accepts a language in NL. Since there is only logarithmic space on the work tape, all possible states of the Turing machine (where a state is the state of the internal finite state machine, the position of the head and the contents of the work tape) are polynomially many. Map all possible states of the deterministic log-space machine to vertices of a graph, and put an edge between u and v if the state v can be reached from u within one step of the non-deterministic machine. Now the problem of whether the machine accepts is the same as the problem of whether there exists a path from the start state to the accepting state.

Savitch's theorem guarantees that the algorithm can be simulated in O(log2 n) deterministic space. 

The same problem for undirected graphs is called undirected s-t connectivity and was shown to be in L by Omer Reingold.  This research won him the 2005 Grace Murray Hopper Award.  Undirected st-connectivity was previously known to be complete for the class SL, so Reingold's work showed that SL is the same class as L. On alternating graphs, the problem is P-complete .

References 

Graph connectivity
Directed graphs
NL-complete problems
Markman v. Westview Instruments, Inc.. Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996), is a United States Supreme Court case on whether the interpretation of patent claims is a matter of law or a question of fact. An issue designated as a matter of law is resolved by the judge, and an issue construed as a question of fact is determined by the jury.

Background 

Herbert Markman patented a system to track clothes through the dry cleaning process using barcode to generate receipts and track inventory.

The 7th Amendment guarantees the right to a jury trial in patent infringement cases. The 7th Amendment preserves the right to a jury trial as it existed in 1791. There is no dispute that infringement cases today must be tried by a jury as their predecessors were in 1791. However, the court held that the construction of the patent, including the terms of art within its claim, is exclusively within the court's province.

In general, the effectiveness of a particular patent depends on its potential to block competitors. The key for a patent holder is getting the proper definition of words used in the patent to allow blocking of the particular troublesome competitive product. Before this decision, juries were responsible for deciding the meaning of the words used in patent claims. Opposing results in cases with similar facts were common, and a perception arose that the outcome of such trials was somewhat arbitrary. In Markman, the Court held that judges, not juries, would evaluate and decide the meaning of the words used in patent claims. Judges were to look at four sources for definitions, in order of priority:

 the written description accompanying the patent claims is most relevant; 
 the documentation of the history of the patent as it went through the application;
 standard dictionaries of English; 
 finally, if all else fails, expert testimony from experts "skilled in the art" at issue.

This case has had a significant impact on the patent litigation process in the United States. Many jurisdictions now hold Markman hearings to construe patent claims before the actual trial. Patent infringement suits now often settle after this stage of the litigation process.

Supreme Court decision
In a unanimous ruling written by Justice David Souter, the court affirmed the judgment of the circuit court, holding that:

 The construction of a patent, including terms of art within its claim, is exclusively within the province of the court.

Law firms involved 
Markman was represented in the original trial by the law firm of Duane Morris, and by the law firm of Eckert Seamans on appeal. Defendants were represented by the law firm of Gollatz, Griffin, Ewing & McCarthy (now Flaster Greenberg) on appeal.

See also 

 List of United States Supreme Court cases, volume 517
 Markman hearing

References

External links
 

United States patent case law
United States Seventh Amendment case law
United States Supreme Court cases
United States Supreme Court cases of the Rehnquist Court
1996 in United States case law
Barcodes
Dry cleaning
Rolladen-Schneider LS5. The Rolladen-Schneider LS5 was an Open Class single seat glider aircraft designed by Rolladen-Schneider. Only a single unit was built.

Design and development
The LS5 was announced in 1980 as Rolladen-Schneider’s entry into the exclusive Open Class. The economic viability of the design was compromised, however, with the arrival in 1981 of the Schempp-Hirth Nimbus-3 and the Schleicher ASW 22, both of which outclassed the predicted performance of the yet-to-fly LS5. Although the moulds had already been completed, Rolladen-Schneider decided not to pursue further development. Klaus Mies from Kaiserslautern used these moulds to produce one glider of the type. This homebuilt prototype made its maiden flight in 1988, receiving the registration number D-7742. It is based at Marpingen in Germany.

Specifications

See also
List of gliders

References 

Geistmann D, Segelflugzeuge in Deutschland, Motorbuch Verlag
LS-Flugzeugbau website
sailplanedirectory.com

1980s German sailplanes
Rolladen-Schneider aircraft
Aircraft first flown in 1988
T-tail aircraft
KMS state. In the statistical mechanics of quantum mechanical systems and quantum field theory, the properties of a system in thermal equilibrium can be described by a mathematical object called a Kubo–Martin–Schwinger (KMS) state: a state satisfying the KMS condition.

Ryogo Kubo introduced the condition in 1957,  and Julian Schwinger  used it in 1959 to define thermodynamic Green's functions, and Rudolf Haag, Marinus Winnink and Nico Hugenholtz used the condition in 1967 to define equilibrium states and called it the KMS condition.

Overview 

The simplest case to study is that of a finite-dimensional Hilbert space, in which one does not encounter complications like phase transitions or spontaneous symmetry breaking. The density matrix of a thermal state is given by

where H is the Hamiltonian operator and N is the particle number operator (or charge operator, if we wish to be more general) and

is the partition function. We assume that N commutes with H, or in other words, that particle number is conserved.

In the Heisenberg picture, the density matrix does not change with time, but the operators are time-dependent. In particular, translating an operator A by τ into the future gives the operator

.

A combination of time translation with an internal symmetry "rotation" gives the more general

A bit of algebraic manipulation shows that the expected values

for any two operators A and B and any real τ (we are working with finite-dimensional Hilbert spaces after all). We used the fact that the density matrix commutes with any function of (H − μN) and that the trace is cyclic.

As hinted at earlier, with infinite dimensional Hilbert spaces, we run into a lot of problems like phase transitions, spontaneous symmetry breaking, operators that are not trace class, divergent partition functions, etc..

The complex functions of z,  converges in the complex strip  whereas  converges in the complex strip  if we make certain technical assumptions like the spectrum of H − μN is bounded from below and its density does not increase exponentially (see Hagedorn temperature). If the functions converge, then they have to be analytic within the strip they are defined over as their derivatives,

and

exist.

However, we can still define a KMS state as any state satisfying

with  and  being analytic functions of z within their domain strips.

 and  are the boundary distribution values of the analytic functions in question.

This gives the right large volume, large particle number thermodynamic limit. If there is a phase transition or spontaneous symmetry breaking, the KMS state is not unique.

The density matrix of a KMS state is related to unitary transformations involving time translations (or time translations and an internal symmetry transformation for nonzero chemical potentials) via the Tomita–Takesaki theory.

See also
 Gibbs state

References

Statistical mechanics
Quantum field theory
Quantum states
IBM 602. The IBM 602 Calculating Punch, introduced in 1946, was an electromechanical calculator capable of addition, subtraction, multiplication, and division. The 602 was IBM's first machine that did division. (The IBM 601, introduced in 1931, only multiplied.) Like other IBM calculators, it was programmed using a control panel. Input data was read from a punched card, the results could be punched in the same card or a trailing card.

The 602 was available in four models: Model 1, Model 2, Model 50, and Model 51. The "Series 50" models were low-cost versions that ran at a slower speed, with half as many program steps, and fewer storage registers and counters.

Two additional counters were available as an optional feature.

Program steps execute in one machine cycle, except for steps performing multiplication or division which take as many machine cycles as needed for the operation. Punching rate is roughly four columns per machine cycle. The total number of machine cycles required per card varies depending on the data and programming.

Programming the 602 for each problem involved two things:
A control panel wired for the sequence of the calculation
A Skip Bar with "inserts" placed for the first column of each field to punch

See also
 IBM 603
 IBM CPC
 IBM 604
 IBM 605
 IBM 608

References

External links
Columbia University Computing History: The IBM 602 Calculating Punch

602
Programmable calculators
Computer-related introductions in 1946
COSYSMO. The Constructive Systems Engineering Cost Model (COSYSMO) was created by Ricardo Valerdi while at the University of Southern California Center for Software Engineering. It gives an estimate of the number of person-months it will take to staff systems engineering resources on hardware and software projects.  Initially developed in 2002, the model now contains a calibration data set of more than 50 projects provided by major aerospace and defense companies such as Raytheon, Northrop Grumman, Lockheed Martin, SAIC, General Dynamics, and BAE Systems.

Similar to its predecessor COCOMO, COSYSMO computes effort (and cost) as a function of system functional size and adjusts it based on a number of environmental factors related to systems engineering.

COSYSMO's central cost estimating relationship, or CER is of the form:

where "Size" is one of four size additive size drivers, and EM represents one of fourteen multiplicative effort multipliers.

See also
 Comparison of development estimation software
 Software development effort estimation

Further reading
 Valerdi, R., Boehm, B., Reifer, D., COSYSMO: A Constructive Systems Engineering Cost Model Coming Age, 13th INCOSE Symposium, July 2003, Crystal City, VA.
 Valerdi, R., The Constructive Systems Engineering Cost Estimation Model (COSYSMO), University of Southern California, May 2005.
 Valerdi, R., The Constructive Systems Engineering Cost Model (COSYSMO): Quantifying the Costs of Systems Engineering Effort in Complex Systems, VDM Verlag, 2008.

External links
 COSYSMO
 SystemStar Tool
 True COSYSMO
 SEER for Systems Engineering

Software engineering costs
Features, events, and processes. Features, Events, and Processes (FEP) are terms used in the fields of radioactive waste management, carbon capture and storage, and hydraulic fracturing to define relevant scenarios for safety assessment studies.  For a radioactive waste repository, features would include the characteristics of the site, such as the type of soil or geological formation the repository is to be built on or under. Events would include things that may or will occur in the future, like, e.g., glaciations, droughts, earthquakes, or formation of faults. Processes are things that are ongoing, such as the erosion or subsidence of the landform where the site is located on, or near.

Several catalogues of FEP's are publicly available, a.o., this one elaborated for the NEA Clay Club dealing with the disposal of radioactive waste in deep clay formations,
and those compiled for deep crystalline rocks (granite) by Svensk Kärnbränslehantering AB, SKB, the Swedish Nuclear Fuel and Waste Management Company.

References

External links
Free PDF reports are accessible from here: 
 Nuclear Energy Agency
 SKB (Sweden) web site
 Posiva (Finland) Databank web site
 NAGRA (Switzerland) web site 

Radioactive waste
Nuclear safety and security
Klaus Holighaus. 

Klaus Holighaus  (14 July 1940 – 9 August 1994) was a glider designer, glider pilot and entrepreneur.

Klaus Holighaus was born in Eibelshausen, Germany.  He started his career in gliding when he was an engineering student at the Technische Hochschule Darmstadt, where he was a member of its Akaflieg. Fellow students Gerhard Waibel and Wolf Lemke had already developed the D-36 glider and he contributed to its refinement.  He joined Schempp-Hirth as an employee in 1965.  He became Chief Executive in 1972 and from 1977 Holighaus was the sole owner of the business. He designed most of the company's products, beginning with the Cirrus until the Nimbus-4.  

Holighaus flew in every German National Championship from 1968, winning six times in the Open Class. He became European Champion three times and finished in the top rankings of the nine World Championships in which he competed.  He held 16 World Records in various categories.

Holighaus was killed in the area of St. Gotthard when flying in the Alps from Samedan, Switzerland. The wreckage was not discovered for two days. The cause of the accident is not clear, but a possible factor was the deteriorating weather on the day and he may have unsuccessfully tried to cross a mountain pass. He had logged 8,168 hours in gliders.

He married Brigitte.  His son, Tilo, continues the Schempp-Hirth business.
After his death, a road in Kirchheim unter Teck was named Klaus-Holighaus-Straße.

References

External links 
Klaus Holighaus biography, Schempp-Hirth website  Retrieved: 15 March 2008

1940 births
1994 deaths
Aviators killed in aviation accidents or incidents in Switzerland
Engineers from Hesse
German aerospace engineers
German glider pilots
People from Lahn-Dill-Kreis
Recipients of the Order of Merit of Baden-Württemberg
Technische Universität Darmstadt alumni
Victims of aviation accidents or incidents in 1994