Search

The article focuses on DigitalDesk, which is a real physical desk where one can stack papers, lay out their favorite pencils and markers, and leave coffee cup, but it is enhanced to provide some characteristics of an electronic workstation. A computer display is projected onto the desk, and video cameras pointed down at the desk feed an image-processing system that can sense what the user is doing. Three important characteristics of DigitalDesk are, it projects electronic images down onto the desk and onto paper documents, it responds to interaction with pens or bare fingers and it can read paper documents placed on the desk. The DigitalDesk provides a computer-augmented environment in which paper gains electronic properties that allow it to overcome some of its physical limitations. The calculator is a simple and familiar application that can benefit from the DigitalDesk. It allows people to place ordinary paper documents on the desk and simply point at a printed number to enter it into the calculator.

Invites several research papers for the forthcoming conferences related to the computing systems.

This article focuses on a conference on "Recent Advances in Computer Simulation Modeling and Statistical Analysis" that was held on April 21-22, 1980 at Columbia University. This conference was organized and chaired by the Guest Editor under the sponsorship of the Special Interest Committee on Simulation of the New York City Chapter of ACM. The first paper develops a unifying approach and a set of definitions to the time and space relationships in simulation modeling. The second and third papers are concerned with the acceptability of simulation models. The first of these two papers presents a framework of concepts and criteria for assessing the acceptability of simulation studies. The other paper presents a methodology for performing a cost-risk analysis in the statistical validation of simulation models of real and observable systems. The fourth paper explores the possibility of using a network of microprocessors for executing simulation models.

The article discusses the factors that affect the sharing of research artifacts relating to computer systems according to the authors. Topics covered include the importance of sharing research artifacts for repeatability and benefaction, the research studies the evaluated the willingness of computer science researchers in sharing code and data, and details relating to the three measures of weak repeatability determined by the authors.

In this paper, we study the problem of estimating the state of a switched linear system (SLS), when the observation of the system is subject to communication constraints. We introduce the concept of worst-case topological entropy of such systems, and we show that this quantity is equal to the minimal data rate (number of bits per second) required for the state estimation of the system under arbitrary switching. Furthermore, we provide a closed-form expression for the worst-case topological entropy of switched linear systems, showing that its evaluation reduces to the computation of the joint spectral radius (JSR) of some lifted switched linear system obtained from the original one by using tools from multilinear algebra, and thus can benefit from well-established algorithms for the stability analysis of switched linear systems. Finally, drawing on this expression, we describe a practical coder-decoder that estimates the state of the system and operates at a data rate arbitrarily close to the worst-case topological entropy. [ABSTRACT FROM AUTHOR]

The article discusses various issues related to academic computer science research. Topics include debates on software-development methodology in relation to independent faults, a debate on the evaluation of file system performance, and the use of software-based attestation (SWATT) as a protocol for checking memory images from remote systems.

The article outlines the professional activities of the Association of Computing Machinery (ACM). The ACM SIGUCCS Users Conference XII is planned for November 11-14, 1984 in Reno, Nevada. ACM SIGMETRICS Conference on Measurement and Modeling of Computer Systems will be held in Boston, Massachusetts on August 2-24, 1984. The 13th Annual Conference on Parallel Processing will be held on August 21-24, 1984 in Bellaire, Michigan. The Third International Conference on Systems Documentation will be held on May 16-18, 1984 in Mexico City.

The article offers information on several conferences related to Association for Computing Machinery (ACM) to be held in 2102 including fourth annual Conference on the Management of Data in San Jose, California on May 14-16, International Computing Symposium (ICS) in Antibes, France on June 2-4, and Annual Symposium on Theory of Computing in Albuquerque, New Mexico on May 5-7.

This article offers information on the Computing Practices section of the magazine "Communications of the ACM." The section focuses on articles with a message about general ideas and techniques that can be transferred from one place to another. Instead of technical papers, the section concentrates on discussions of how, what, why and when to use the computing methods and systems. Topics that cover areas of interest to readers of the section include improvement of the systems design process, future of computing, and implication of new theory to application systems.

Errors in dynamic random access memory (DRAM) are a common form of hardware failure in modern compute clusters. Failures are costly both in terms of hardware replacement costs and service disruption. While a large body of work exists on DRAM in laboratory conditions, little has been reported on real DRAM failures in large production clusters. In this paper, we analyze measurements of memory errors in a large fleet of commodity servers over a period of 2.5 years. The collected data covers multiple vendors, DRAM capacities and technologies, and comprises many millions of dual in-line memory module (DIMM) days. The goal of this paper is to answer questions such as the following: How common are memory errors in practice? What are their statistical properties? How are they affected by external factors, such as temperature and utilization, and by chipspecific factors, such as chip density, memory technology, and DIMM age? We find that DRAM error behavior in the field differs in many key aspects from commonly held assumptions. For example, we observe DRAM error rates that are orders of magnitude higher than previously reported, with 25,000- 70,000 errors per billion device hours per Mb and more than 8% of DIMMs affected by errors per year. We provide strong evidence that memory errors are dominated by hard errors, rather than soft errors, which previous work suspects to be the dominant error mode. We find that temperature, known to strongly impact DIMM error rates in lab conditions, has a surprisingly small effect on error behavior in the field, when taking all other factors into account. Finally, unlike commonly feared, we do not observe any indication that newer generations of DIMMs have worse error behavior. [ABSTRACT FROM AUTHOR]

Monitoring and troubleshooting distributed systems are notoriously difficult; potential problems are complex, varied, and unpredictable. The monitoring and diagnosis tools commonly used today—logs, counters, and metrics—have two important limitations: what gets recorded is defined a priori, and the information is recorded in a component- or machine-centric way, making it extremely hard to correlate events that cross these boundaries. This paper presents Pivot Tracing, a monitoring framework for distributed systems that addresses both limitations by combining dynamic instrumentation with a novel relational operator: the happened-before join. Pivot Tracing gives users, at runtime, the ability to define arbitrary metrics at one point of the system, while being able to select, filter, and group by events meaningful at other parts of the system, even when crossing component or machine boundaries. Pivot Tracing does not correlate cross-component events using expensive global aggregations, nor does it perform offline analysis. Instead, Pivot Tracing directly correlates events as they happen by piggybacking metadata alongside requests as they execute. This gives Pivot Tracing low runtime overhead—less than 1% for many cross-component monitoring queries. [ABSTRACT FROM AUTHOR]

This article focuses on conferences related to computer systems. The 1981 Winter Simulation Conference to be held on December 9-11 in Atlanta, Georgia, is to feature papers, panel discussions, and tutorials on discrete and combined (Discrete/Continuous) simulation modeling; The 15th Annual Simulation Symposium is planned for March 17-19, 1982 in Tampa, Florida; The Fifteenth Hawaii International Conference on System Sciences, Honolulu, January 6-8. 1982, is to cover developments in theory or practice in the areas of computer software and hardware and advanced systems applications; The National Educational Computing Conference 81 is set for June 17-19 at North Texas State University in Denton, Texas; An International Conference on Systems Methodology, organized by the Society for General Systems Research and sponsored by the International Federation for Systems Research, is planned for January 5-9, 1982, in Washington D.C.

The article offers information on several conferences and call for papers including the 1977 Association for Computing Machinery (ACM) Computer Science Conference on January 31-February 2, fifth annual Symposium on the Simulation of Computer System in Gaithersbug, Maryland on August 9-11, 1977, and the annual Simulation Symposium in Tampa, Florida on March 16-18, 1977.

The article presents a calendar of events related to computers. The 1985 National Computer Conference will be held on July 15 to 18 in Chicago, Illinois. The Artificial Intelligence in Economics and Management workshop will be held on March 12 to 14, 1985, in Zurich, Switzerland. The World Conference on Computers in Education (WCCE) will be held on July 29 to August 2, 1985, in Norwolk, Virginia.

The article offers information on various conferences for professionals. The Working Conference on Prototyping will be held on October 25-28, 1983 at Hotel Sofitel in Namur, Belgium. The International Workshop on Models and Languages for Software Specification and Design will be held on March 30, 1984 in Orlando, Florida. The 1984 National Education Computing Conference will be held on June 13-15 in Dayton, Ohio.

The article presents a calendar of professional activities and special events concerning the Association of Computing Machinery. Activities feature meetings and symposiums in programming languages, computer architecture, softair program, information technology, and other important meetings about computers.

In this paper an axiomatic, fundamental metamodel of data flow is constructed. The components of the metamodel are the states along the flow of data: physical events, language (data), stored data, human data processing, and decision making. Transfers front one state to another are performed by functions: coding, keying, processing, perception, and human acting. The entire flow is evaluated by a value function. Each of the states and functions is rigorously described by means of definitions, axioms, and theorems. The main purpose of the meta model is to provide a common framework for various models in MIS and consequently to remedy the "Tower of Babel" syndrome prevailing in this area. The way the metamodel can he used to develop other models in MIS is explained in the last part of the paper. [ABSTRACT FROM AUTHOR]

The article offers news briefs related to information technology. The Association for Systems Management (ASM) has announced a program to certify systems personnel and to recertify every three years those who continue their educations and comply with a code of conduct. The organization Information Age Institute has been formed to study the impact of information technology in Washington, D.C.

This paper discusses a family of algorithms for computing the volume, moments of inertia, and other integral properties of geometrically complex solids, e.g. typical mechanical parts. The algorithms produce approximate decompositions of solids into cuboid cells whose integral properties are easy to compute. The paper focuses on versions of the algorithms which operate on solids represented by Constructive Solid Geometry (CSG), i.e., as set-theoretical combinations of primitive solid "building blocks." Two known algorithms are summarized and a new algorithm is presented. The efficiencies and accuracies of the three algorithms are analyzed theoretically and compared experimentally. The new algorithm uses recursive subdivision to convert CSG representations of complex solids into approximate cellular decompositions based on variably sized blocks. Experimental data show that the new algorithm is efficient and has predictable accuracy. It also has other potential applications, e.g., in producing approximate octree representations of complex solids and in robot navigation. [ABSTRACT FROM AUTHOR]

This paper presents a model of an I/O subsystem in which devices can be accessed from multiple CPUs and/or via alternative channel and control unit paths. The model estimates access response times, given access rates for all CPU-device combinations. Central to the model's algorithm is the estimation of the rotational position sensing (RPS) miss probabilities by means of the maximum entropy principle. [ABSTRACT FROM AUTHOR]

The article presents news briefs concerning the Association of Computing Machinery (ACM). Mostek Corp. has become Corporate Member of ACM. ACM modified its own copyright procedures with respect to papers published in ACM journals. John Tartar has been appointed ACM Chairman of the External Activities Board.

Analytical results, related to the availability of a computer system constructed of unreliable processors, are presented in this paper. These results are obtained by using various computer-aided algebraic manipulation techniques. A major purpose of this paper is to demonstrate that the difficulties of obtaining analytical solutions to Markov processes can be considerably reduced by the application of symbol manipulation programs. Since many physical systems can be modeled by Markov and semi-Markov processes, the potential range of application of these techniques is much wider than the problem of availability analyzed here. [ABSTRACT FROM AUTHOR]

Foreword. At every standards meeting, in clear view on the table there should be a small plaque engraved: "Do it once, do it right, do it internationally." The many contributions of Douglas Ross exemplify this directive. If, for example, you look at the ASCII standard, ANSI-X3.4-1968, you will find that D.T. Ross represented ACM on the ANSI X3 Committee at that time. This paper is part of an argument that well-founded standards go hand in hand with an effective systems methodology. When first submitted for refereeing, "Homilies for Humble Standards" was oriented toward Computer Aided Manufacturing (CAM) applications. As it is now published, the context is elevated to consider all applications. In a similar manner, we can broaden the scope to show that it is the concern of all ACM members. Manufacturing is the application of tools and processes on materials to create a product. Languages are our tools, algorithms and procedures are our processes, data is our material. The product is an enhancement of the power and span of control of the customer. I commend this paper for your reading as one of the relatively few in ACM publications which tell why ACM and its members should be "involved", it discusses an unsolved problem, rather than a solution looking for a problem. [ABSTRACT FROM AUTHOR]

The article provides information on the origins of computer science and technology, in light of the 100th anniversary of the birth of computer scientist Alan Turing in 2012. The author emphasizes that Turing did not invent the computer. In 1936, Turing launched the concept called the Turing Machine, which has become the main abstract model of computation used by computer scientists. After the Second World War, he designed an electronic computer called the automatic computing engine (ACE) for the National Physical Laboratory in London, England. It discusses the role of Turing in the founding of theoretical computer science.

The article presents abstracts of research papers related to information technology. The research paper "Transactions and Consistency in Distributed Database Systems," discusses the concepts of transaction and data consistency for distributed computing systems. The cases of partitioned data, where fragments of a file are stored at multiple nodes, and replicated data, where a file is replicated at several nodes, are discussed. It has been argued that the distribution and replication of data should be transparent to the programs which use the data. That is, the programming interface should provide location transparency, replica transparency, and failure transparency. According to the research paper "On the Correct Translation of Update Operations on Relational Views," most relational database systems provide a facility for supporting user views. Permitting this level of abstraction has the danger, however, that update requests issued by a user within the context of his view may not translate correctly into equivalent updates on the underlying database.

The article offers information on several conferences of the Association for Computing Machinery (ACM) including the Sigmetrics Conference on Measurement and Modeling of Computer Systems to be held on August 30- September 1, 1982, the Northwest Conference to be held on June 23-26, 1982, and the International Conference on Management of Distribution Data Processing to be held on June 23-26, 1982.

The article focuses on the information for authors on the general topics for their contribution in the magazine "Communications of the ACM." categories of the papers include general interest articles, case studies, special sections and reports. There are also several channels for expressions of opinion. General interest articles cover material of substance and emphasize concepts and principles. An article sets the background, defines fundamental concepts, compares alternate approaches, and explains the significance or application of a particular theory or result by means of good written and visual material. Articles that deal with computing practices emphasize the skills arid techniques used daily in the practice of computing, including the design and construction of applications systems; discussion of computer systems and tools. Case studies are articles that report on experiences gained and lessons learned constructing and using major computer systems. They take a comprehensive view of selected systems, covering them from requirements through design, implementation, and use. Special sections and issues are collections of articles on a specific topic. Reports are official documents issued by committees, panels, and task forces.

It seems that the vision of the Internet grew out of the realization that users of the first, experimental time-sharing systems formed communities. The time-sharing experiments were funded by the Advanced Research Projects Agency of the U.S. Department of Defense, originally ARPA, now DARPA, under the leadership of J.C.R. Licklider, who had championed interactive computing in an influential paper on man-machine symbiosis. Licklider soon recognized the importance of electronic communities and the initial ARPANET development was funded. The ARPANET project refined the vision and pioneered techniques used on the Internet. It was followed by the Internet, which serves the research and education communities, and by many commercial and proprietary networks. The Internet, the major research and education network, grew from the 4-node ARPANET in 1969 to an estimated 992,000 hosts by September 1992. The growth rate is over 1,000 hosts per day, and it is accelerating. Its size can only be estimated, and continues to grow while, the estimation procedure runs.

The article presents a study on the impact of a computerized record system on work lives of customer service representatives in a large utility company. The study includes 10 offices employing a total of 485 service representatives in 6 cities. Top management decided to automate the customer service department to increase efficiency and cut labor costs. They installed equipment that would computerize information that service representatives had previously viewed on microfiche and altered by completing paper transaction records. Compared to the microfiche system it replaced, the interactive computer system was to provide service representatives with more recent billing information in a more convenient way and to allow interactive updating of customers' accounts. To provide the informational support for these customer contact tasks, each representative had a microfiche reader and a set of microfiche copies of recent bills for all accounts serviced by that office. Older bills were kept in a central storage area, and service representatives had to leave their desks to retrieve them.

Focuses on the issues related to computing and communications in the United States. Issuance of a directory of mandatory and voluntary standards activities; Establishment of a Software Engineering Institute; Public review of the American National Standard X3.30-1971.

Several letters to the editor commenting on the paper "Social Processes and Proofs of Theorems and Programs," by De Millo, Lipton and Perlis are presented.

This paper presents methods for empirical evaluation of features of Instruction Set Processors (ISPs). ISP features are evaluated in terms of the time used or saved by having or not having the feature. The methods are based on analysis of traces of program executions. The concept of a register life is introduced, and used to answer questions like: How many registers are used simultaneously? How many would be sufficient all of the time? Most of the time? What would the overhead be if the number of registers were reduced? What are registers used for during their lives? The paper also discusses the problem of detecting desirable but non-existing instructions. Other problems are briefly discussed. Experimental results are presented, obtained by analyzing 41 programs running on the DECsystem 10 ISP. [ABSTRACT FROM AUTHOR]

This article examines how the development of batteryless devices are the future of Internet of Things devices. The article first looks into the research that allows for intermittent computing. Necessary components for these batteryless systems, including new programming languages and wireless networks, are discussed. Then the article explores six required directions to make batteryless devices successful, including energy-minimal computer architecture and foundation experimental infrastructure.

Focuses on the issues related to computer policies in the United States. Assistance of the government in university research; Improvement of the information flow from the Federal laboratories to the industries; Emphasis of the Senate bill on the promotion of international trade.

The article offers information on events related to information processing including the 14th Annual Conference of the Association for Computing Machinery's (ACM) Special Interest Group Computer Personnel Research which will be held in Alexandria, Virginia on July 29 and 30, 1976 and the Fourth International Conference on the Implementation and Design of Algorithmic Languages to be held from June 14 to 16 at the New York University Courant Institute of Mathematical Sciences.

The article presents information on several events and conferences held during the year 1981. The Proceedings of the 18th Design Automation Conference was held in Nashville, Tennessee from June 29-July 1, 1981. The Proceedings of the 18th Annual Computer Personnel Research Conference was held in Washington D.C. from June 3-5, 1981. The Proceedings of the 13th Annual ACM Symposium on Theory of Computing was held in Milwaukee, Wisconsin from May 11-13, 1981. The Proceedings of the International Conference on Management of Data was held in Ann Arbor, Michigan from April 29-May 1, 1981. The Proceedings of the 5th International Conference on Software Engineering was held in San Diego, California from March 9-12, 1981. The Proceedings of the ACM SIGPLAN Symposium on the Ada Programming Language was held in Boston, Massachusetts from December 9-11, 1980. The Proceedings of the ACM SIGPLAN-SIGOA Symposium on Text Manipulation was held in Portland, Oregon from June 8-10, 1981.

This article offers information on the Computing Practices section of the magazine "Communications of the ACM." The section was initiated as a part of an effort of the Association for Computing Machinery (ACM) to publish more material of direct and immediate interest to computing practitioners. The general scope of the section includes the design and construction of application systems, discussion of computer systems, tools and techniques as they relate application systems to the larger computing environment, and methodologies for the management of the data processing function.

The article discusses about the dependence of human beings on complex automated systems. At work, at home, at play, on the streets, in sickness and in health, human beings are ever more dependent on computers and networks for support, even survival. If this is continued, human beings will not have the knowledge and skill to weather a major crash. Liberation from intellectual toil carries certain risks, since capacities can atrophy from disuse. Thus, one should render to computer what is the computer's, and to the human being what is the human being's. Everything has limitations. Commenting on the one-person-one-vote principle in a democracy, Bertrand Russell observed that in a population of n, a person has a 1/n share in the government of the community, but at the same time only a 1/n share in the governance of oneself. This does not argue against democracy, but in favor of parsimony in granting government jurisdiction over issues that could be handled by the individual. Similarly, care should be exercised in assigning tasks to the computer. No formula for such an allocation is at hand. There is no substitute for eternal vigilance.

The article presents a calendar of events of professional activities related to computing machineries in 1985. The Conference on Human Factors in Computing Systems will be held in San Francisco, California, from April 14 to 18. The National Computer Conference will be held in Chicago, Illinois, from July 15 to 18. The International Conference on Modeling Techniques and Tools for Performance Analysis will be held in Sophia-Antipolis, France, from June 5 to 7.

Contrary to recent claims that specification should be completed before implementation begins, this paper presents two arguments that the two processes must be intertwined. First, limitations of available implementation technology may force a specification change. For example, deciding to implement a stack as an array (rather than as a linked list) may impose a fixed limit on the depth of the stack. Second, implementation choices may suggest augmentations to the original specification. For example deciding to use an existing pattern-match routine to implement the search command in an editor may lead to incorporating some of the routine's features into the specification, such as the ability to include wild cards in the search key. This paper elaborates these points and illustrates how they arise in the specification of a con- troller for a package router. [ABSTRACT FROM AUTHOR]

An introduction is presented for a paper on the Naiad Dataflow System of computers.

The article presents a list of the top ten most popular papers available on ACM's Refereed Journals and Conference Proceedings digital library for the month of May 2006. Papers include "Architectures for a Temporal Workflow Management System," by Carlo Combi and Giuseppe Pozzi, "An Example Oriented On-line Java Tutorial for University Students," by Jianna J. Zhang and Huy Nguyen, "Evolution of Web Site Design Patterns," by Melody Y. Ivory and Rodrick Megraw, and "Events Not Equal to GUIs," by Stuart Hansen and Timothy Fossum.

This article focuses on the code of election law. Elections are governed by intricate and voluminous codes of law that, in turn, are transformed into the program code that governs the functionality of computer systems used in election processes. Voting systems reflect the interaction of technology and governance as grounded in the history of democracy in the locality in which they reside. Variances of election law are therefore as great as the differences in history of democratic nations and states. Voting technology is diffused in a context where the governmental parties in a democracy may have strong and vested interests in the reliability of the technology, or alternatively may wish to ensure that the technology can be allowed to be subverted to favor certain groups or individuals. In computerized voting, decisions intended to assist the voter can remove critical choices. Overvoting and undervoting are examples of actions, generally viewed as undesirable, that can be effectively prohibited or reduced by election system designs.

This article focuses on the use of electronic voting systems in Georgia. The history of elections and computers in Georgia is unique. DeKalb and Fulton counties in the metro-Atlanta area were the first jurisdictions in the U.S. to use computers to tally votes in a primary election in October 1964. Georgia was the first state to adopt a uniform, statewide direct-recording electronic (DRE) technology in 2002. Georgia has a model system for the deployment and management of elections technology, which combines the resources of its Secretary of State (SOS), its University system, and its county election officials. In the general election of 2000 the voters in Georgia voted on a variety of election devices. Two of the smallest counties used hand-counted paper ballots, 73 counties voted on mechanical lever machines, 17 counties voted on punch-card voting systems, and 67 counties voted on optical-scan voting systems. Deployment of the DRE technology in the summer of 2002 was characterized by the conviction of the SOS that Georgia should eliminate technological barriers to voting, such as undervotes or spoiled ballots.

The article discusses research on cache behavior and computer system performance. It references the study "Learning Your Limit: Managing Massively Multithreaded Caches Through Scheduling" by Timothy G. Rogers published in the current issue of the journal. Topics discussed include the different objectives for the cache that have led to different trade-offs in modern graphics processing unit (GPU) and central processing unit (CPU) systems.

The article presents a list of publications related to computer systems that were published during September 1-30, 1975. Some of the publications are SIGMINI (Minicomputers) in the SIGMINI Newsletter; SIGARCH (Architecture of Computer Systems) in the Computer Architecture News; SIGART (Artificial Intelligence) in the SIGART Newsletter; SIGCAS (Computers and Society) in the SIGCAS Newsletter; SIGCUE (Computer Uses in Education) in the SIGCUE Bulletin; and SIGMICRO (Microprogramming) in the SIGMICRO Newsletter.

English logician and mathematician Alan Turing, in an attempt to develop a working definition of intelligence free of the difficulties and philosophical pitfalls of defining exactly what constitutes the mental process of intelligent reasoning, devised a test, instead, of intelligent behavior. The idea, codified in his celebrated 1950 paper "Computing Machinery and intelligence," was specified as an "imitation game'' in which a judge attempts to distinguish which of two agents is a human and which a computer imitating human responses by engaging each in a wide ranging conversation of any topic and tenor. Turing's reasoning was, presuming that intelligence only practically determinable behaviorally, that any agent that was indistinguishable in behavior from an intelligent agent was, for all intents and purposes,intelligent. It is presumably uncontroversial that humans are intelligent as evidenced by their conversational behavior. Thus, any agent that can be mistaken by virtue of its conversational behavior with a human must he intelligent.

Flexible representations are required in order to understand and generate expert behavior. Although production rules with quantifiers can encode experiential knowledge, they often have assumptions implicit in them, making them brittle in problem scenarios where these assumptions do not hold. Qualitative models achieve flexibility by representing the domain entities and their interrelationships explicitly. However, in problem domains where assumptions underlying such models change periodically, it is necessary to be able to synthesize and maintain qualitative models in response to the changing assumptions. In this paper we argue for a representation that contains partial model components that are synthesized into qualitative models containing entities and relationships relevant to the domain. The model components can be replaced and rearranged in response to changes in the task environment. We have found this "model constructor" to be useful in synthesizing models that explain and generate expert behavior, and have explored its ability to support decision making in the problem domain of business resource planning, where reasoning is based on models that evolve in response to changing external conditions or internal policies. [ABSTRACT FROM AUTHOR]

The article presents abstracts related to computers. They include "The Format Model: A Theory of Database Organization," "Analysis of Interleaved Storage via a Constant-Service Queuing System with Markov-Chain-Driven Input," "Solving NP-Hard Problems on Graphs that Are Almost Trees and an Application to Facility Location Problems."

The article presents abstracts related to computers. They include "The Format Model: A Theory of Database Organization," "Analysis of Interleaved Storage via a Constant-Service Queuing System with Markov-Chain-Driven Input," "Solving NP-Hard Problems on Graphs that Are Almost Trees and an Application to Facility Location Problems."