One of the major difficulties in controlling software development project cost overruns and schedule delays has been developing practical and accurate software cost models. Software development could be modeled as an ...
详细信息
One of the major difficulties in controlling software development project cost overruns and schedule delays has been developing practical and accurate software cost models. Software development could be modeled as an economic production process and we therefore propose a theoretical approach to software cost modeling. Specifically, we present the Minimum Software Cost Model (MSCM), derived from economic production theory and systems optimization. The MSCM model is compared with other widely used software cost models, such as COCOMO and SLIM, on the basis of goodness of fit and quality of estimation using software project data sets available in the literature. Judged by both criteria, the MSCM model is comparable to, if not better than, the SLIM, and significantly better than the rest of the models. In addition, the MSCM model provides some insights about the behavior of software development processes and environment, which could be used to formulate guidelines for better software project management polic es and practices.
Query Refinement is an essential information retrieval tool that interactively recommends new terms related to a particular query. This paper introduces concept recall, an experimental measure of an algorithm's ab...
ISBN:
(纸本)0897918363
Query Refinement is an essential information retrieval tool that interactively recommends new terms related to a particular query. This paper introduces concept recall, an experimental measure of an algorithm's ability to suggest terms humans have judged to be semantically related to an information need. This study uses precision improvement experiments to measure the ability of an algorithm to produce single term query modifications that predict a user's information need as partially encoded by the query. An oracle algorithm produces ideal query modifications, providing a meaningful context for interpreting precision improvement results. This study also introduces RMAP, a fast and practical query refinement algorithm that refines multiple term queries by dynamically combining precomputed suggestions for single term queries. RMAP achieves accuracy comparable to a much slower algorithm, although both RMAP and the slower algorithm lag behind the best possible term suggestions offered by the oracle. We believe RMAP is fast enough to be integrated into present day Internet search engines: RMAP computes 100 term suggestions for a 160,000 document collection in 15 ms on a low-end PC.
作者：
Chris McDonaldKamran KazemiProgramming
Languages and Systems Group Department of Computer Science The University of Western Australia Crawley Western Australia 6907
The parallel programming community has long recognized the need for a simple programming environment offering interprocess communication between heterogeneous systems. As the Parallel Virtual Machine environment, PVM,...
ISBN:
(纸本)9780897918893
The parallel programming community has long recognized the need for a simple programming environment offering interprocess communication between heterogeneous systems. As the Parallel Virtual Machine environment, PVM, has emerged to meet this goal, an increasing number of educational institutions are choosing PVM to support their teaching of parallel and distributed computing using networks of workstations. However, it is often the nature of PVM's design and implementation that can severely limit its success in a teaching environment. This paper first motivates and then describes improvements to the PVM environment which increase both robustness and efficiency in an educational setting.
作者：
Sammons, DanielDaniel G. Sammons is a Systems Consultant in Walldorf
Germany currently on assignment to Bull AG. He graduated from programming school in 1965 in New York and has worked in Germany since 1968 having been stationed there while on active duty in the US Army
Giant awake - Lilliputians sleeping… It is striking to think that while a £3 million a year supercomputer complete with robot and human operator(s) is running all night on the ground floor, the floors above are ...
Giant awake - Lilliputians sleeping… It is striking to think that while a £3 million a year supercomputer complete with robot and human operator(s) is running all night on the ground floor, the floors above are mostly dark - although there is more disk capacity and MIPS in the building, turned off and silent up there, already purchased by the company, than are running downstairs. So how about shifting the work to the other computers, and getting rid of Madame Mainframe? Sounds like a good idea. But to move in that direction with any chance of ultimate success involves rethinking one's entire viewpoint on client/server architecture. The spectacles we put on to see solutions to other problems could prevent us from seeing the solution to this one
Object-oriented (OO) software development techniques have gained in popularity as an attractive alternative to the traditional, structured development approach. Fundamental to the OO approach is the object, which bund...
详细信息
Object-oriented (OO) software development techniques have gained in popularity as an attractive alternative to the traditional, structured development approach. Fundamental to the OO approach is the object, which bundles data with associated operations in a self-contained unit. The inherently modular object provides an excellent mechanism for creating reusable, stable, and easily maintainable code. In this paper, we present an introduction to OO development; discuss the challenges of large, complex systems; and document the procedures we developed to meet these challenges for our project.
作者：
Modell, DJDonald J. Modell:is a project manager and senior technical consultant with Smith Environmental Technologies Corporation (BCM Engineers
Inc.). Mr. Modell has extensive experience in process control systems (PLCs PCs distributed control systems and SCADA systems) and sensors used in the environmental and remedial engineering processes and operations. Mr. Modell has further experience with software and hardware configuration programming implementation and total quality management techniques. He has received master's degrees in environmental engineering and chemical engineering from The Johns Hopkins University and Case Western Reserve University. Mr. Modell also has an M.B.A. in finance from Case Western Reserve University. He is active in The American Industrial Hygiene Association the American Institute of Chemical Engineers the International Society of Measurement and Control the Sociely of American Military Engineers and is an officer in the National and Maryland Society of Professional Engineers. He serves as a director and advisor to the legdative board fm the Maryland Engineering Society Joint Council.
On-line real-time monitoring of marine and operational exhaust stacks and process streams can play a critical role in providing safe, environmentally sound operation of marine and industrial processes using volatile o...
详细信息
On-line real-time monitoring of marine and operational exhaust stacks and process streams can play a critical role in providing safe, environmentally sound operation of marine and industrial processes using volatile organic species. Monitoring systems are needed that are inexpensive and powerful to be effective. It has been demonstrated that two independent responses, wave velocity and wave attenuation can be obtained from surface acoustic wave devices coated with viscoelastic polymers. This output technique enables identification and concentration determination of isolated species with a single sensor. This paper discusses the development of the sensor devices and the basis of portable acoustic wave sensor systems (which are being used) to monitor volatile organic compounds from marine and industrial chemical processes. Furthermore, on-line monitoring of spray cleaning processes has been effective in quantifying how emissions can be decreased based on substituting solvents, optimizing worker protocols, and utilizing new spray nozzle configurations.
Fail-safety is a system attribute which ensures that a program either completes its execution satisfying its post-conditions in the normal manner or signals its failure to do so to its operating environment. Such an a...
详细信息
Fail-safety is a system attribute which ensures that a program either completes its execution satisfying its post-conditions in the normal manner or signals its failure to do so to its operating environment. Such an attribute is desirable of any system as it ensures the correctness of results which are produced. A very few modern sequential programming languages offer program fail-safety through the judicious use of a well designed exception handling mechanism. In this paper the exception handling techniques used in those sequential systems are developed to provide the guidelines for fail-safe concurrent system design. (C) 1997 Elsevier Science Ltd.
作者：
Smolka, GProgramming Systems Lab
German Research Center for Artificial Intelligence (DFKI) Universität des Saarlandes Geb. 45 Postfach 15 11 50 Saarbüicken D-66041 Germany
暂无评论