From the bitsavers.org collection, a scanned-in computer-related document. computerResearchCorp :: 01 TS Sys Scorecard Spring65

Topics: system, california, systems, computer, ibm, denotes, storage, consoles, mit, fortran, project mac,...

From the bitsavers.org collection, a scanned-in computer-related document. computerResearchCorp :: 03 TS Sys Scorecard Spring66

Topics: ibm, system, fortran, mit, california, crt, computer, rand, storage, corporation, project mac, rand...

From the bitsavers.org collection, a scanned-in computer-related document. computerResearchCorp :: 02 TS Sys Scorecard Fall65

Topics: ibm, fortran, system, mit, california, computer, algol, systems, crt, languages, project mac,...

A complete classification is given of all (22,11) and (24,12) self- dual codes. For each code the authors give the order of its group, the number of codes equivalent to it, and its weight distribution. There is a unique (24, 12,6) self-dual code. Several theorems on the enumeration of self-orthogonal codes are used, including formulas for the number of such codes with minimum distance or = 4, and for the sum of the weight enumerators of all self-dual codes.

Topics: DTIC Archive, Pless, Vera, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *CODING,...

The design and specification of a common base language for procedures and information structures is discussed. The report envisions the meanings of programs expressed in practical source languages as defined by rules of translation into the base language. The meanings of programs in the base language are specified by a transition system that is an interpreter for the base language. The base language interpreter serves as the functional specification of a computer system with emphasis on...

Topics: DTIC Archive, Dennis, Jack B, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *PROGRAMMING...

From the bitsavers.org collection, a scanned-in computer-related document. computerResearchCorp :: 04 TS Sys Scorecard Fall66

Topics: ibm, system, fortran, systems, california, mit, crt, computer, rand, university, rand tablet,...

From the bitsavers.org collection, a scanned-in computer-related document. mit :: lcs :: tr :: MIT-LCS-TR-013

Topics: simulation, data, user, computer, operators, system, vector, ops, figure, programming, project mac,...

The report is an attempt to produce a bibliography covering all aspects of computer and data security, and having annotations that more than superficially describe each article's content. This bibliography contains 1,022 entries. About half of these entries are extensively annotated, another quarter being superficially annotated, and the rest being unannotated. All extensively annotated entries are rated as to their current usefulness and uniqueness. A subject index of 160 items is provided for...

Topics: DTIC Archive, Scherf, John A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *SECURITY,...

This memo describes a practical application within the framework of the ARPA computer network of the philosophy that a fully developed computer network should appear as a virtual extension of the user's own software environment. The application involves the design and implementation of a software facility that will permit users at MIT's Dynamic Modeling System to consider the retrieval component of the Datacomputer (developed and run by the Computer Corporation of America) as an extension of...

Topics: DTIC Archive, Bengelloun, Safwan A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER...

With the ever-increasing amount of data stored on computers, the need for security in transmission becomes greater and greater. The author considers some new stream enciphering schemes based on J-K flip-flops. The data is considered to be a stream of binary bits. There are two main types of encipherment schemes; a block scheme and a stream scheme. Since the aim of this paper is to present some new stream enciphering schemes, the author describes briefly a general stream enciphering scheme.

Topics: DTIC Archive, Pless, Vera, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA PROCESSING...

PILOT is a programming system constructed in LISP. It is designed to facilitate the development of programs by easing the familiar sequence: write some code, run the program, make some changes, write some more code, run the program again, etc. As a program becomes more complex, making these changes becomes harder and harder because the implications of changes are harder to anticipate. In the PILOT system, the computer plays an active role in this evolutionary process by providing the means...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER PROGRAMMING, *MAN MACHINE...

A new type of information retrieval system is suggested which utilizes data of the type generated by users of the system instead of data generated by indexers. The theoretical model on which the system is based consists of three basic elements. The first element is a measure of the relatedness between document-pairs. It is derived from information theory. The second element is a definition of what constitutes a set (cluster) of inter- related documents. This definition is based on the measure...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *INFORMATION RETRIEVAL, COMPUTERS,...

The report describes the use of new language for the control of Physical processes. Programs written in Macro Control Language are subjected to a translator/scheduler where they undergo a traditional compilation as well as automatic processor scheduling among the various processes which are controlled. The memo explains the syntax and semantics of the Macro Control Language. It also gives step-by-step instructions for writing programs and for running them on the M.I.T. Electrical Engineering...

Topics: DTIC Archive, Geiger, Steven P, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *PROGRAMMING...

The main purpose of the paper is to lay a mathematical basis for the study of flip-flops. A J-K flip-flop is a device with 2 inputs (zero or one) and two outputs, one of which is always the complement of the other. A counter is a set of J-K flip-flops whose inputs are either constants (0 or 1) or outputs of other flip-flops in the counter. The paper only considers J-K flip-flops whose inputs are outputs of the other flip-flops. Whenever an n-counter is referred to, it shall mean such a counter...

Topics: DTIC Archive, Pless, Vera, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *LOGIC CIRCUITS,...

Topics: DTIC Archive, Moll, Robert, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *RECURSIVE FUNCTIONS,...

Topics: DTIC Archive, Ferrante, Jeanne, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *MATHEMATICAL...

New and improved algorithms for computation in several fundamental polynomial operations are presented. The common basis for these algorithms are generalizations of the p-adic technique used in the constructive proof of the Hensel Lemma. Multivariate polynomial operations are stressed due to the special importance of the multivariate Hensel-type construction in replacing the modular evaluation-and-interpolation technique under certain conditions. Due to the availability of numerous methods for...

Topics: DTIC Archive, Yun, David Y, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *ALGEBRA,...

The paper defines and studies the invariant subcodes, (R sub sigma) (q) and (R sub mu)(q), of the symmetry code C(q) in order to be able to determine the algebraic properties of these codes. Every vector in (R sub sigma)(q) is invariant under a monomial transformation tau, odd order dividing (q + 1), in the group of C(q). Also (R sub mu)(q) is invariant under tau but not vector-wise. The dimensions of (R sub sigma)(q) and (R sub mu)(q) are determined and relations between these subcodes are...

Topics: DTIC Archive, Pless, Vera, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *CODING, ALGEBRA,...

The purpose of the paper is to give an alternative proof to the decidability of the emptiness problem for tree automata, as shown in another paper. The proof reduces the emptiness problem for automata on infinite trees to that for automata on finite trees, by showing that any automata definable set of infinite trees must contain a finitely-generable tree.

Topics: DTIC Archive, Hossley, Robert, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *AUTOMATA,...

The thesis describes a design for an automatic backup mechanism to be incorporated in a computer utility for the protection of on-line information against accidental or malicious destruction. This protection is achieved by preserving on magnetic tape recent copies of all items of information known to the on-line file system. In the event of a system failure, file system damage is automatically assessed and missing information is recovered from backup storage. For isolated mishaps, users may...

Topics: DTIC Archive, Stern, Jerry A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA PROCESSING...

Although deterministic top-down parsing is an attractive parsing technique, the grammars to which it is applicable (the LL(k) grammars) are but a small subset of the LR(k) grammars, those that can be parsed deterministically bottom-up. In this thesis, the problem of transforming LR(k) grammars into equivalent LL(k) grammars is studied. A new transformation procedure is devised which is more powerful than currently available techniques and which preserves the compiling ability of the grammar.

Topics: DTIC Archive, Hammer, Michael M, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC,...

In a previous paper Rabin defined Automata on Infinite Trees, and the body of that paper is concerned with proving two theorems about these automata. The result the author considers in the report states that there exists an effective procedure to determine, given an automaton on infinite trees, whether or not it accepts anything at all. An alternative proof is presented which reduces the emptiness problem for automata on infinite trees to that for automata on finite trees. This proof is much...

Topics: DTIC Archive, Rackoff, Charles Weill, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC,...

A model for the auxiliary memory function of a segmented, multi- processor, time-shared computer system is set up. A drum system in particular is discussed, although no loss of generality is implied by limiting the discussion to drums. Particular attention is given to the queue of requests waiting for drum use. It is shown that a shortest access time first queue discipline is the most efficient, with the access time being defined as the time required for the drum to be positioned, and is...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *QUEUEING THEORY, MILITARY...

This paper describes the implementation of a compiler for the programming language C. The compiler has been designed to be capable of producing assembly-language code for most register-oriented machines with only minor recoding. Most of the machine-dependent information used in code generation is contained in a set of tables which are constructed automatically from a machine description provided by the implementer. In the machine description, the implementer models the target machine by...

Topics: DTIC Archive, Snyder, Alan, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPILERS,...

A programming system is a computer system which supports a community of programmers who can make use of one another's work. A module is a (possibly complex) construction usually comprising both programs and data which will provide some service. A programming system is said to be modular if modules can be constructed within the system from existing modules using only knowledge about the behaviour of those existing modules. In such a system: mechanisms must exist which permit any module to be...

Topics: DTIC Archive, Henderson, Jr, D A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER...

The relationship between the page size, program behavior, and page fetch frequency in storage hierarchy systems is formalized and analyzed. It is proven that there exist cyclic program reference patterns that can cause page fetch frequency to increase significantly if the page size used is decreased (e. g., reduced by half). Furthermore, it is proven in Theorem 3 that the limit to this increase is a linear function of primary store size. Thus, for example, on a typical current-day paging system...

Topics: DTIC Archive, Madnick, Stuart E, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER...

The expressive power of a particular applicative language may be characterized by the set of abstract directly representable in that language. The common FUNARG and applicative order problems are scrutinized in this way, and the effects of these weaknesses are related to the inexpressibility of classes of functions. Certain computable functions which are inexpressible in the lambda calculus are identified, and it is established that the interpretation of these functions requires a mechanism...

Topics: DTIC Archive, Ward, Stephen A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *PROGRAMMING...

The research discusses a program which aids the user of an automatic programming system (APS) in the debugging of his model of his problem situation. The problem domain considered in the thesis is that of business games (i.e., the management simulation games which are used as a learning tool in the study of management). A language for describing models of these games is presented. The paper then describes the program's methods of simulating and finding bugs in models written in this language....

Topics: DTIC Archive, Mark, William S, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *ARTIFICIAL...

Modern, large-scale computer systems typically operate under the control of an operating system or executive program, and reserve for the exclusive use of the operating system a set of privileged instructions, which the normal users may not issue. This very necessary arrangement produces a problem of equipment availability for those who wish to develop or investigate operating systems programs, because such programs cannot be run as normal user jobs under an executive program. The thesis...

Topics: DTIC Archive, McCray, William A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA...

The report describes research into some properties of autonomous, synchronous counters constructed with only the simplest form of J-K Flip-Flop. The research revolved around a system with a special-purpose digital machine and a general-purpose computer. The special-purpose machine searched through all the possible counters constructed of five or fewer J-K Flip-Flops for all counters with a period equal to that specified by the input to the systems. The descriptions of the counters found were...

Topics: DTIC Archive, Manning, Frank, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *LOGIC CIRCUITS,...

The broad goal of Project MAC is experimental investigation of new ways in which on-line use of computers can aid people in their individual work; whether research, engineering design, management, or education. (Author)

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTERS, ARTIFICIAL...

The purpose of the work is to investigate the number of arithmetic operations required by algorithms which evaluate polynomials. Previous results show that a polynomial of degree n requires at least n/2 multiplication/ divisions and at least n addition/subtractions for its evaluation if the coefficients of the polynomial are suitably independent irrational numbers. However, the coefficients of any polynomial that would be evaluated in practice are represented only to a finite accuracy and are...

Topics: DTIC Archive, Stockmeyer, Larry Joseph, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC,...

The paper presents the design and implementation of a Language Implementation System (LIS) and investigates the use of that system in the development of artificial languages and their associated processors. The language Implementation System accepts the formal definition of the syntax and semantics of an artificial language, and synthesizes a processor for that language. The parsers (lexical and primary) of the processor are highly efficient Deterministic Push Down Automata (DPDAs) computed...

Topics: DTIC Archive, Altman, Vernon E, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *PROGRAMMING...

Blum's machine-independent treatment of the complexity of partial recursive functions is extended to relative algorithms (as represented by Turing machines with oracles). The author proves relativeizations of several results of Blum complexity theory. A recursive relatedness theorem is proved, showing that any two relative complexity measures are related by a fixed recursive function. This theorem allows one to obtain proofs of results for all measures from proofs for a particular measure. The...

Topics: DTIC Archive, Lynch, Nancy A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *MATHEMATICAL...

Recently IBM Corporation has declassified an algorithm for encryption usable for computer-to-computer or computer-to-terminal communications. Their algorithm was implemented in a hardware device called Lucifer. A software implementation of Lucifer for MULTICS is described. A proof of the algorithm's reversibility for deciphering is provided. A special hand-coded (assembly language) version of Lucifer is described whose goal is to attain performance as close as possible to that of the hardware...

Topics: DTIC Archive, Benedict, G G, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *CODING,...

The research addresses the problem of file organization for efficient information retrieval when each file item may be accessed through any one of a large number of identification keys. The emphasis is on library problems, namely large, low-update, directory-oriented files, but other types of files are discussed. The model used introduces the concept of an ideal directory against which all imperfect real implementations (catalogs) can be compared. The use of an ideal reference point serves to...

Topics: DTIC Archive, Welch, Terry A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *INFORMATION...

In many large systems, user I/O must be performed for the user by the system, in order to assure such system goals as security, response, and efficiency. However, reduced overhead and increased flexibility would result if the user could perform his I/O directly. This thesis presents a design for an I/O subsystem architecture which, in the context of a segmented, paged, time- shared computer system, allows the user direct access to I/O devices. Some conclusions of this thesis are: (1) that in...

Topics: DTIC Archive, Clark, David D, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *INPUT OUTPUT...

In order to enforce the security of the information stored in a computing utility, it is necessary to certify the correctness of the protection mechanism. Certification requires that the security kernel of the system be much smaller and simpler than the supervisor of present general purpose operating systems. The report explores one aspect of simplifying the kernel of a system by designing a dynamic linker that runs outside the kernel domain. The linker is designed to run in any user domain of...

Topics: DTIC Archive, Janson, Philippe A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA...

This document describes DALI (Display Algorithm Language Interpreter) , a special-purpose programming language for the creation and control of changing pictures which exhibit complex static and dynamic interactions among their elements. DALI allows complex organizations if interpolated (smooth) change, discrete change, and change in the structure of a picture to be generated in a modular way, in the sense that picture elements determine their own behavior and hence manner of change.

Topics: DTIC Archive, Pfister, Gregory F, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER...

The design of airplanes, ships, automobiles, and so-called 'sculptured parts' involves the design, delineation, and mathematical description of bounding surfaces. A method is described which makes possible the description of free-form doubly curved surfaces of a very general kind. An extension of these ideas to hyper-surfaces in higher dimensional spaces is also indicated. This surface technique has been specifically devised for use in the Computer-Aided Design Project at M.I.T., and has...

Topics: DTIC Archive, Coons, Steven A, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *SHELLS(STRUCTURAL...

The paper describes a system for the computer understanding of English. The system answers questions, executes commands, and accepts information in normal English dialog. It uses semantic information and context to understand discourse and to disambiguate sentences. It combines a complete syntactic analysis of each sentence with a 'heuristic understander' which uses different kinds of information about a sentence, other parts of the discourse, and general information about the world in deciding...

Topics: DTIC Archive, Winograd, Terry, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTER...

From the bitsavers.org collection, a scanned-in computer-related document. computerResearchCorp :: 05 TS Sys Scorecard Fall67

Topics: ibm, fortran, california, system, crt, cdc, sds, computer, systems, university, system named,...

The report describes practical protection mechanisms that allow mutually suspicious subsystems to cooperate in a single computation and still be protected from one another. The mechanisms are based on the division of a computation into independent domains of access privilege, each of which may encapsulate a protected subsystem. The central component of the mechanisms is a hardware processor that automatically enforces the access constraints associated with a multidomain computation implemented...

Topics: DTIC Archive, Schroeder, Michael D, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA...

The properties of capability-based extendible operating systems are described, and various aspects of such systems are discussed, with emphasis on the conflict between free distribution of access privileges and later revocation of those privileges. The discussion culminates in a set of goals for a new scheme. A new design is then proposed, which provides both type extension and revocation through the definition of generalized sealing of capabilities. The implementation of this design is...

Topics: DTIC Archive, Redell, David D, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA PROCESSING...

The notion of machine-aided cognition implies an intimate collaboration between a human user and a computer in a real-time dialogue on the solution of a problem, in which the two parties contribute their best capabilities. In order for this intimate collaboration to be possible, a computer system is needed that can serve simultaneously a large number of people, and that is easily accessible to them, both physically and intellectually. The present MAC System is a first step toward this goal. The...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTERS, COMPUTER PROGRAMMING,...

The paper traces the evolution of a segment based file system. The final system is typical of the virtual memory systems found in large general purpose time-sharing systems. The contents of the file system is a collection of symbolically named segments organized in a hierarchial structure. The user directly references segments in the file system. All movement of information between the different levels of physical memory is done automatically by the system using paging. Complete privacy of user...

Topics: DTIC Archive, Graham, Robert M, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *DATA PROCESSING,...

A requirement exists for a low-cost remote display terminal with alphanumeric and line-drawing capabilities for use with time-shared computer systems. A survey of existing devices and character generation techniques was carried out, and a design approach was chosen which takes advantage of mass- fabrication techniques. This includes using a five-by-seven dot matrix raster and a resistor array 'read-only' character memory for the 96 printable symbols of the Revised Proposed ASCII Code. Circuits...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *COMPUTERS, REAL TIME, COMPUTER...

Comparators which sort two numbers can be interconnected to form networks which sort N numbers for any N. The input and output characteristics of comparator networks are analyzed from several different points of view.

Topics: DTIC Archive, Smith, Burton J, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *LOGIC CIRCUITS,...

Deficiencies of various programming languages for dealing with quantities frequently encountered in cryptanalysis of simple cipher systems are discussed. A programming system is proposed which will permit a cryptanalyst to write and debug programs to aid in the solution of cryptograms or cryptographic systems. The basic elements of the proposed programming system are discussed in detail. They include: (1) a programming language to handle both algebraic quantities and character strings, (2) a...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE PROJECT MAC, *CRYPTOGRAPHY, *COMPUTERS,...

BCPL is a language which is readable and easy to learn, as well as admitting an efficient compiler capable of generating efficient code. It is made self consistent and easy to define accurately by an underlying structure based on a simple idealized object machine. The treatment of data types is unusual and it allows the power and convenience of a language with dynamically varying types and yet the efficiency of FORTRAN. BCPL has been used successfully to implement a number of languages and has...

Topics: DTIC Archive, Richards, Martin, Evans, Jr, Arthur, Mabee, Robert F, MASSACHUSETTS INST OF TECH...