Aarhus University is the largest and second oldest research university in Denmark. The University is placed in the top 100 in most prestigious rankings of the world's best universities, belongs to the Coimbra Group and Utrecht Network of European universities and is a member of the European University Association; the university was founded in Aarhus, Denmark, in 1928 and comprises four faculties in Arts and Technology, Business and Social Sciences and has a total of twenty-seven departments and is home to over thirty internationally recognised research centres, including fifteen Centres of Excellence funded by the Danish National Research Foundation. The business school within Aarhus University, called Aarhus BSS, holds the EFMD Equis accreditation, the Association to Advance Collegiate Schools of Business and the Association of MBAs; this makes the business school of Aarhus University one of the few in the world to hold the so-called Triple Crown accreditation. Times Higher Education ranks Aarhus University in the top 10 of the most beautiful universities in Europe.
The university's alumni include Bjarne Stroustrup, the inventor of programming language C++, Queen Margrethe II of Denmark, Crown Prince Frederik of Denmark, Anders Fogh Rasmussen, former Prime Minister of Denmark and a Secretary General of NATO. It has affiliations with three Nobel Laureates: Jens Christian Skou in Chemistry, Trygve Haavelmo in Economics and Dale T. Mortensen in Economics. Aarhus University was founded on 11 September 1928 as Universitetsundervisningen i Jylland with a budget of 33,000 Dkr and an enrollment of 64 students, which rose to 78 during the first semester; the university was founded as a response to the increasing number of students at the University of Copenhagen after World War I. Classrooms were rented from the Technical College and the teaching corps consisted of one professor of philosophy and four associate professors of Danish, English and French. Along with Universitets-Samvirket which consisted of representatives of Aarhus' businesses and institutions, the municipality of Aarhus had fought since 1921 to have Denmark's next university located in the city.
In 1929, the municipality of Aarhus gave the university land with a landscape of rolling hills. The design of the university buildings and 12 ha campus area was assigned to architects C. F. Møller, Kay Fisker and Povl Stegmann, who won the architectural competition in 1931. Construction of the first buildings began a year but the campus was developed in stages and is still under development as of 2017. Since 1939, C. F. Møller Architects has been responsible for the architectural design of Aarhus University in accordance with the original functionalist design key best exemplified by the characteristic yellow brick and tile; the first buildings was finished in 1933 and housed the Departments of Chemistry and Anatomy. These departments moved to newer buildings at the campus and the original building complex now house Department of Psychology and Department of Political Science; the construction of the first stage was funded by donations which totaled 935,000 Dkr and the buildings covered an area of 4,190m2.
One of the most generous contributors to the first stage was De Forenede Teglværker i Aarhus led by director K. Nymark. Forenede Teglværker decided to donate 1 million yellow bricks and tiles worth c. 50,000 Dkr and decided to extend the donation to all bricks needed. The inauguration on 11 September 1933, marked the first official use of the name Aarhus University and was celebrated in a tent on campus, attended by King Christian X, Queen Alexandrine, their son Crown Prince Frederick and Prime Minister Stauning together with 1000 invited guests. On 23 April 1934, Aarhus University was given permission to hold examinations by the king and on 10 October 1935, Professor Dr. phil. Ernst Frandsen was appointed the first rector of the university. Shortages of materials and a stressed economy and delayed further development of Aarhus University. In 1941, construction of The Main Building commenced, a complex to house the university aula and canteen among academic and administrative purposes; the stringent minimalist and uncompromising functionalistic design of the first university buildings from 1933 had stirred some local dissatisfaction and it was decided that The Main Building should possess more traditional romantic and classical architectural inspirations - although in agreement with the original architectural plan -, make use of more lavish and expensive materials.
The Main Building was finished in 1946 and still stands out from the rest of the University campus as somewhat different in its architectural design. In comparison with the original 4,190m2 floor space of the first buildings, Aarhus University now holds a floor space of 246,000m2 in the University Park alone. A series of buildings outside the main campus adds an additional floor space of 59,000m2. From 1928, Aarhus University offered courses in languages and philosophy, but the students were unable to finish their studies without going to the University of Copenhagen for their final examinations. By request of the Ministry of Education, the Teachers' Association made a draft of how to conduct the final examinations in the humanistic subjects in Aarhus and in the draft, the Association proposed that the faculty was named the Faculty of Humanities by analogy with the corresponding faculties in Uppsala and Turku. After negotiations between the faculties in Aarhus and Copenhagen, the King declared on 8
Eli Biham is an Israeli cryptographer and cryptanalyst a professor at the Technion Israeli Institute of Technology Computer Science department. Starting from October 2008 and till 2013, Biham was the dean of the Technion Computer Science department, after serving for two years as chief of CS graduate school. Biham received his Ph. D. for inventing differential cryptanalysis, while working under Adi Shamir. It had, been invented at least twice before. A team at IBM discovered it during their work on DES, was requested/required to keep their discovery secret by the NSA, who evidently knew about it as well. Among his many contributions to cryptanalysis one can count: differential cryptanalysis - publicly invented during his Ph. D. studies under Adi Shamir Attacking all triple modes of operation. Impossible differential cryptanalysis - joint work with Adi Shamir and Alex Biryukov Breaking the ANSI X9.52 CBCM mode Breaking the GSM security mechanisms Co-invention of related-key attacks. Differential Fault Analysis - joint work with Adi Shamir Biham has taken part in the design of several new cryptographic primitives: Serpent, a block cipher, one of the final five contenders to become the Advanced Encryption Standard Tiger, a hash function fast on 64-bit machines, Py, one of a family of fast stream ciphers.
SHAvite-3, a hash function, one of the 14 semifinalists in the NIST hash function competition. Eli Biham's homepage at Technion
Data Encryption Standard
The Data Encryption Standard is a symmetric-key algorithm for the encryption of electronic data. Although its short key length of 56 bits, criticized from the beginning, makes it too insecure for most current applications, it was influential in the advancement of modern cryptography. Developed in the early 1970s at IBM and based on an earlier design by Horst Feistel, the algorithm was submitted to the National Bureau of Standards following the agency's invitation to propose a candidate for the protection of sensitive, unclassified electronic government data. In 1976, after consultation with the National Security Agency, the NBS selected a modified version, published as an official Federal Information Processing Standard for the United States in 1977; the publication of an NSA-approved encryption standard resulted in its quick international adoption and widespread academic scrutiny. Controversies arose out of classified design elements, a short key length of the symmetric-key block cipher design, the involvement of the NSA, nourishing suspicions about a backdoor.
Today it is known that the S-boxes that had raised those suspicions were in fact designed by the NSA to remove a backdoor they secretly knew. However, the NSA ensured that the key size was drastically reduced such that they could break it by brute force attack; the intense academic scrutiny the algorithm received over time led to the modern understanding of block ciphers and their cryptanalysis. DES, as stated above, is insecure; this is due to the 56-bit key size being too small. In January 1999, distributed.net and the Electronic Frontier Foundation collaborated to publicly break a DES key in 22 hours and 15 minutes. There are some analytical results which demonstrate theoretical weaknesses in the cipher, although they are infeasible to mount in practice; the algorithm is believed to be secure in the form of Triple DES, although there are theoretical attacks. This cipher has been superseded by the Advanced Encryption Standard. Furthermore, DES has been withdrawn as a standard by the National Institute of Standards and Technology.
Some documentation makes a distinction between DES as a standard and as an algorithm, referring to the algorithm as the DEA. The origins of DES go back to the early 1970s. In 1972, after concluding a study on the US government's computer security needs, the US standards body NBS —now named NIST —identified a need for a government-wide standard for encrypting unclassified, sensitive information. Accordingly, on 15 May 1973, after consulting with the NSA, NBS solicited proposals for a cipher that would meet rigorous design criteria. None of the submissions, turned out to be suitable. A second request was issued on 27 August 1974; this time, IBM submitted a candidate, deemed acceptable—a cipher developed during the period 1973–1974 based on an earlier algorithm, Horst Feistel's Lucifer cipher. The team at IBM involved in cipher design and analysis included Feistel, Walter Tuchman, Don Coppersmith, Alan Konheim, Carl Meyer, Mike Matyas, Roy Adler, Edna Grossman, Bill Notz, Lynn Smith, Bryant Tuckerman.
On 17 March 1975, the proposed DES was published in the Federal Register. Public comments were requested, in the following year two open workshops were held to discuss the proposed standard. There was some criticism from various parties, including from public-key cryptography pioneers Martin Hellman and Whitfield Diffie, citing a shortened key length and the mysterious "S-boxes" as evidence of improper interference from the NSA; the suspicion was that the algorithm had been covertly weakened by the intelligence agency so that they—but no-one else—could read encrypted messages. Alan Konheim commented, "We sent the S-boxes off to Washington, they came back and were all different." The United States Senate Select Committee on Intelligence reviewed the NSA's actions to determine whether there had been any improper involvement. In the unclassified summary of their findings, published in 1978, the Committee wrote: In the development of DES, NSA convinced IBM that a reduced key size was sufficient. However, it found that NSA did not tamper with the design of the algorithm in any way.
IBM invented and designed the algorithm, made all pertinent decisions regarding it, concurred that the agreed upon key size was more than adequate for all commercial applications for which the DES was intended. Another member of the DES team, Walter Tuchman, stated "We developed the DES algorithm within IBM using IBMers; the NSA did not dictate a single wire!" In contrast, a declassified NSA book on cryptologic history states: In 1973 NBS solicited private industry for a data encryption standard. The first offerings were disappointing, so NSA began working on its own algorithm. Howard Rosenblum, deputy director for research and engineering, discovered that Walter Tuchman of IBM was working on a modification to Lucifer for general use. NSA gave Tuchman a clearance and brought him in to work jointly with the Agency on his Lucifer modification." And NSA worked with IBM to strengthen the algorithm against all except brute-force attacks and to strengthen substitution tables, called S-boxes. Conversely, NSA tried to convince IBM to reduce the length of the key from 64 to 48 bi
Technical University of Denmark
The Technical University of Denmark simply referred to as DTU, is a university in Kongens Lyngby, just north of Copenhagen, Denmark. It was founded in 1829 at the initiative of Hans Christian Ørsted as Denmark's first polytechnic, is today ranked among Europe's leading engineering institutions. DTU, along with École Polytechnique, École Polytechnique Fédérale de Lausanne, Eindhoven University of Technology, Technical University of Munich, is a member of Eurotech Universities. DTU was founded in 1829 as the'College of Advanced Technology' with the physicist Hans Christian Ørsted a professor at the University of Copenhagen, as one of the driving forces; the inspiration was the École Polytechnique in Paris, France which Ørsted had visited as a young scientist. The new institution was inaugurated on 5 November 1829 with Ørsted as its principal, a position he held until his death in 1851; the new college's first home was two buildings in Studiestræde and St- Pederstræde in central Copenhagen. Although expanded several times, they remained inadequate and in 1890 a new building complex was inaugurated in Sølvgade in 1890.
The new buildings were designed by the architect Johan Daniel Herholdt. In 1903 the College of Advanced Technology commenced the education of electrical engineers in addition to the construction engineers, production engineers and mechanical engineers educated at the college. In the 1920s space had once again become insufficient and in 1929 the foundation stone was laid for a new school at Østervold. Completion of the building was delayed by World War II and it was not completed until 1954. From 1933 the institution was known as Danmarks tekniske Højskole, translated as the'Technical University of Denmark'. On 1 April 1994, in connection with the joining of Danmarks Ingeniørakademi and DTH, the Danish name was changed to Danmarks Tekniske Universitet, in order to include the word'University', thus giving rise to the initials DTU by which the university is known today; the formal name, Den Polytekniske Læreanstalt, Danmarks Tekniske Universitet, still includes the original name. In 1960 a decision was made to move the College of Advanced Technology to new and larger facilities in Lyngby north of Copenhagen.
They were inaugurated on 17 May 1974. On 23 and 24 November 1967 the University Computing Center hosted the NATO Science Committee's Study Group first meeting discussing the newly coined term'Software Engineering'. On 1 January 2007 the university was merged with the following Danish research centers: Forskningscenter Risø, Danmarks Fødevareforskning, Danmarks Fiskeriundersøgelser, Danmarks Rumcenter, Danmarks Transport-Forskning; the university is governed by a board consisting of 10 members: six members recruited outside the university form the majority of the board, one member is appointed by the scientific staff, one member is appointed by the administrative staff, two members are appointed by the university students. The President of DTU is appointed by the university board; the president in turn appoints deans, deans appoint heads of departments. In 2014, DTU was granted an institutional accreditation by the Danish Accreditation Institution; the institutional accreditation ensures that the quality assurance system of the institution is well-described, well-argued, well-functioning in practice.
Since DTU has no faculty senate, since the faculty is not involved in the appointment of president, deans, or department heads, the university has no faculty governance. The university is located on a plain known as Lundtoftesletten in the northeastern end of the city of Lyngby; the area was home to the airfield Lundtofte Flyveplads. The campus is divided in half by the road Anker Engelunds Vej going in the east-west direction, perpendicular to that, by two lengthy, collinear roads located on either side of a parking lot; the campus is thus divided into four parts, referred to as quadrants, numbered 1 through 4 in correspondence with the conventional numbering of quadrants in the Cartesian coordinate system with north upwards. In 2018 there were two gun shootings in the area; the shootings have happened on Lundtoftevej between cars. DTU was the subject of controversy in 2009 because the former institute director of the Department of Chemistry was a high-ranking member of Scientology. In relation to this, the university was accused of violating the principles of free speech by threatening to fire employees who voice their criticism of the institute director.
On 7 April 2010, his successor was announced, at a department meeting, as Erling Stenby, who took over as Director on 1 May 2010. Shortly thereafter, the university management threatened Rolf W. Berg with dismissal for publicly criticizing the university. In November 2007 the Times Higher Education Supplement put the university as number 130 in their ranking of the universities of the world and number 122 in 2010. In "The World's Most Innovative Universities" 2015 ranking by Thomson Reuters, DTU is ranked:No. 1 in the Nordic countries No. 43 in the World In the "engineering" category in the QS subject rankings, DTU is ranked: No. 2 in the Nordic countries No. 36 in the World On the Leiden Ranking's 2008 "crown indicator" list of Europe's 100 largest universities in terms of the number of Web of Science publications in the period 2000–2007, DTU is ranked:No. 1 in the Nordic countries No. 5 in Europe In the 2015 QS World University Rankings DTU is ranked: No. 112 in the World In the 2013 Leiden Ranking DTU is ranked: No. 45 in the World No. 7 in Europe In the 2013–2014 Times Hi
Computer science is the study of processes that interact with data and that can be represented as data in the form of programs. It enables the use of algorithms to manipulate and communicate digital information. A computer scientist studies the theory of computation and the practice of designing software systems, its fields can be divided into practical disciplines. Computational complexity theory is abstract, while computer graphics emphasizes real-world applications. Programming language theory considers approaches to the description of computational processes, while computer programming itself involves the use of programming languages and complex systems. Human–computer interaction considers the challenges in making computers useful and accessible; the earliest foundations of what would become computer science predate the invention of the modern digital computer. Machines for calculating fixed numerical tasks such as the abacus have existed since antiquity, aiding in computations such as multiplication and division.
Algorithms for performing computations have existed since antiquity before the development of sophisticated computing equipment. Wilhelm Schickard designed and constructed the first working mechanical calculator in 1623. In 1673, Gottfried Leibniz demonstrated a digital mechanical calculator, called the Stepped Reckoner, he may be considered the first computer scientist and information theorist, among other reasons, documenting the binary number system. In 1820, Thomas de Colmar launched the mechanical calculator industry when he released his simplified arithmometer, the first calculating machine strong enough and reliable enough to be used daily in an office environment. Charles Babbage started the design of the first automatic mechanical calculator, his Difference Engine, in 1822, which gave him the idea of the first programmable mechanical calculator, his Analytical Engine, he started developing this machine in 1834, "in less than two years, he had sketched out many of the salient features of the modern computer".
"A crucial step was the adoption of a punched card system derived from the Jacquard loom" making it infinitely programmable. In 1843, during the translation of a French article on the Analytical Engine, Ada Lovelace wrote, in one of the many notes she included, an algorithm to compute the Bernoulli numbers, considered to be the first computer program. Around 1885, Herman Hollerith invented the tabulator, which used punched cards to process statistical information. In 1937, one hundred years after Babbage's impossible dream, Howard Aiken convinced IBM, making all kinds of punched card equipment and was in the calculator business to develop his giant programmable calculator, the ASCC/Harvard Mark I, based on Babbage's Analytical Engine, which itself used cards and a central computing unit; when the machine was finished, some hailed it as "Babbage's dream come true". During the 1940s, as new and more powerful computing machines were developed, the term computer came to refer to the machines rather than their human predecessors.
As it became clear that computers could be used for more than just mathematical calculations, the field of computer science broadened to study computation in general. In 1945, IBM founded the Watson Scientific Computing Laboratory at Columbia University in New York City; the renovated fraternity house on Manhattan's West Side was IBM's first laboratory devoted to pure science. The lab is the forerunner of IBM's Research Division, which today operates research facilities around the world; the close relationship between IBM and the university was instrumental in the emergence of a new scientific discipline, with Columbia offering one of the first academic-credit courses in computer science in 1946. Computer science began to be established as a distinct academic discipline in the 1950s and early 1960s; the world's first computer science degree program, the Cambridge Diploma in Computer Science, began at the University of Cambridge Computer Laboratory in 1953. The first computer science degree program in the United States was formed at Purdue University in 1962.
Since practical computers became available, many applications of computing have become distinct areas of study in their own rights. Although many believed it was impossible that computers themselves could be a scientific field of study, in the late fifties it became accepted among the greater academic population, it is the now well-known IBM brand that formed part of the computer science revolution during this time. IBM released the IBM 704 and the IBM 709 computers, which were used during the exploration period of such devices. "Still, working with the IBM was frustrating if you had misplaced as much as one letter in one instruction, the program would crash, you would have to start the whole process over again". During the late 1950s, the computer science discipline was much in its developmental stages, such issues were commonplace. Time has seen significant improvements in the effectiveness of computing technology. Modern society has seen a significant shift in the users of computer technology, from usage only by experts and professionals, to a near-ubiquitous user base.
Computers were quite costly, some degree of humanitarian aid was needed for efficient use—in part from professional computer operators. As computer adoption became more widespread and affordable, less human assistance was needed for common usage. Despite its short history as a formal academic discipline, computer science has made a number of fundamental contributions to science and society—in fact, along with electronics, it is
In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called a block, with an unvarying transformation, specified by a symmetric key. Block ciphers operate as important elementary components in the design of many cryptographic protocols, are used to implement encryption of bulk data; the modern design of block ciphers is based on the concept of an iterated product cipher. In his seminal 1949 publication, Communication Theory of Secrecy Systems, Claude Shannon analyzed product ciphers and suggested them as a means of improving security by combining simple operations such as substitutions and permutations. Iterated product ciphers carry out encryption in multiple rounds, each of which uses a different subkey derived from the original key. One widespread implementation of such ciphers, named a Feistel network after Horst Feistel, is notably implemented in the DES cipher. Many other realizations of block ciphers, such as the AES, are classified as substitution–permutation networks.
The publication of the DES cipher by the United States National Bureau of Standards in 1977 was fundamental in the public understanding of modern block cipher design. It influenced the academic development of cryptanalytic attacks. Both differential and linear cryptanalysis arose out of studies on the DES design; as of 2016 there is a palette of attack techniques against which a block cipher must be secure, in addition to being robust against brute-force attacks. A secure block cipher is suitable only for the encryption of a single block under a fixed key. A multitude of modes of operation have been designed to allow their repeated use in a secure way to achieve the security goals of confidentiality and authenticity. However, block ciphers may feature as building blocks in other cryptographic protocols, such as universal hash functions and pseudo-random number generators. A block cipher consists of two paired algorithms, one for encryption, E, the other for decryption, D. Both algorithms accept a key of size k bits.
The decryption algorithm D is defined to be the inverse function of encryption, i.e. D = E−1. More formally, a block cipher is specified by an encryption function E K:= E: k × n → n, which takes as input a key K of bit length k, called the key size, a bit string P of length n, called the block size, returns a string C of n bits. P is called the plaintext, C is termed the ciphertext. For each K, the function EK is required to be an invertible mapping on n; the inverse for E is defined as a function E K − 1:= D K = D: k × n → n, taking a key K and a ciphertext C to return a plaintext value P, such that ∀ K: D K = P. For example, a block cipher encryption algorithm might take a 128-bit block of plaintext as input, output a corresponding 128-bit block of ciphertext; the exact transformation is controlled using a second input – the secret key. Decryption is similar: the decryption algorithm takes, in this example, a 128-bit block of ciphertext together with the secret key, yields the original 128-bit block of plain text.
For each key K, EK is a permutation over the set of input blocks. Each key selects one permutation from the set of! Possible permutations. Most block cipher algorithms are classified as iterated block ciphers which means that they transform fixed-size blocks of plaintext into identical size blocks of ciphertext, via the repeated application of an invertible transformation known as the round function, with each iteration referred to as a round; the round function R takes different round keys Ki as second input, which are derived from the original key: M i = R K i where M 0 is the plaintext and M r the ciphertext, with r being the number of rounds. Key whitening is used in addition to this. At the beginning and the end, the data is modified with key material: M 0 = M ⊕ K 0 M i = R K
Integrated Authority File
The Integrated Authority File or GND is an international authority file for the organisation of personal names, subject headings and corporate bodies from catalogues. It is used for documentation in libraries and also by archives and museums; the GND is managed by the German National Library in cooperation with various regional library networks in German-speaking Europe and other partners. The GND falls under the Creative Commons Zero licence; the GND specification provides a hierarchy of high-level entities and sub-classes, useful in library classification, an approach to unambiguous identification of single elements. It comprises an ontology intended for knowledge representation in the semantic web, available in the RDF format; the Integrated Authority File became operational in April 2012 and integrates the content of the following authority files, which have since been discontinued: Name Authority File Corporate Bodies Authority File Subject Headings Authority File Uniform Title File of the Deutsches Musikarchiv At the time of its introduction on 5 April 2012, the GND held 9,493,860 files, including 2,650,000 personalised names.
There are seven main types of GND entities: LIBRIS Virtual International Authority File Information pages about the GND from the German National Library Search via OGND Bereitstellung des ersten GND-Grundbestandes DNB, 19 April 2012 From Authority Control to Linked Authority Data Presentation given by Reinhold Heuvelmann to the ALA MARC Formats Interest Group, June 2012