A distributed computing system is characterized as follows: 1. It has a number of hardware processors with each processor having a certain computing capability. 2. Communications links exist between or among the proce...
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A distributed computing system is characterized as follows: 1. It has a number of hardware processors with each processor having a certain computing capability. 2. Communications links exist between or among the processors. 3. A number of functional components reside on each processor, and the software components of different processors may be synchronous or asynchronous. 4. The functional components interact for the purpose of performing some system-wide functions. To deal with a distributed computing system as defined, the framework of an approach is presented for developing the system's design specifications. In this approach, data components and functional components are handled separately. A notation for the design is supplied, and performance estimates are given.
The typical design process for the relational database model develops the conceptual schema and each of the external schemas separately and independently from each other. This paper proposes a new design methodology t...
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The typical design process for the relational database model develops the conceptual schema and each of the external schemas separately and independently from each other. This paper proposes a new design methodology that constructs the conceptual schema in such a way that overlappings among external schemas are reflected. If the overlappings of external schemas do not produce transitivity at the conceptual level, then with our design method, the relations in the external schemas can be realized as a join over independent components. Thus, a one-to-one function can be defined for the mapping between tuples in the external schemas to tuples in the conceptual schema. If transitivity is produced, then we show that no such function is possible and a new technique is introduced to handle this special case.
As a result of recent technological developments there is an increasing interest in the interconnection of microcomputers through networks. For general computation the interconnection graphs should have short internod...
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As a result of recent technological developments there is an increasing interest in the interconnection of microcomputers through networks. For general computation the interconnection graphs should have short internode communication paths and should be of low degree, systematically structured, and incrementally extensible. A family of graphs, called multitree structured (MTS) having these properties is presented. The MTS graphs of degree three have the maximum number of nodes, known to date, for given diameters.
The modehng and analysis of drum-hke storage units are discussed. Two common forms of drum organizations and two common scheduhng dlsclphnes are considered the file drum and the paging drum;first-m-first-out (FIFO) sc...
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Moderate resolution imaging spectroradiometer(MODIS) imaging has various applications in the field of ground monitoring,cloud classification and meteorological ***,the limitations of the sensors and external disturban...
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Moderate resolution imaging spectroradiometer(MODIS) imaging has various applications in the field of ground monitoring,cloud classification and meteorological ***,the limitations of the sensors and external disturbance make the resolution of image still limited in a certain *** goal of this paper is to use a single image super-resolution(SISR) method to predict a high-resolution(HR) MODIS image from a single low-resolution(LR) ***,although the method based on sparse representation has tackled the ill-posed problem effectively,two fatal issues have been ***,many methods ignore the relationships among patches,resulting in some unfaithful ***,the high computational complexity of sparse coding using l_1 norm is needed in reconstruction *** this work,we discover the semantic relationships among LR patches and the corresponding HR patches and group the documents with similar semantic into topics by probabilistic Latent Semantic Analysis(p LSA).Then,we can learn dual dictionaries for each topic in the low-resolution(LR) patch space and high-resolution(HR) patch space and also pre-compute corresponding regression matrices for dictionary ***,for the test image,we infer locally which topic it corresponds to and adaptive to select the regression matrix to reconstruct HR image by semantic *** method discovered the relationships among patches and pre-computed the regression matrices for ***,our method can greatly reduce the artifacts and get some speed-up in the reconstruction *** manifests that our method performs MODIS image super-resolution effectively,results in higher PSNR,reconstructs faster,and gets better visual quality than some current state-of-art methods.
Analysis of biomedical images is an important step in quantification of various diseases such as human spontaneous intracerebral brain hemorrhage (ICH). In particular, the study of outcome in patients having ICH requi...
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Analysis of biomedical images is an important step in quantification of various diseases such as human spontaneous intracerebral brain hemorrhage (ICH). In particular, the study of outcome in patients having ICH requires measurements of various ICH parameters such as hemorrhage volume and their change over time. A multiresolution probabilistic approach for segmentation of CT head images is presented in this work. This method views the segmentation problem as a pixel labeling problem. In this application the labels are: background, skull, brain tissue, and ICH. The proposed method is based on the Maximum A-Posteriori (MAP) estimation of the unknown pixel labels. The MAP method maximizes the a-posterior probability of segmented image given the observed (input) image. Markov random field (MRF) model has been used for the posterior distribution. The MAP estimation of the segmented image has been determined using the simulated annealing (SA) algorithm. The SA algorithm is used to minimize the energy function associated with MRF posterior distribution function. A multiresolution SA (MSA) has been developed to speed up the annealing process. MSA is presented in detail in this work. A knowledge-based classification based on the brightness, size, shape and relative position toward other regions is performed at the end of the procedure. The regions are identified as background, skull, brain, ICH and calcifications.
In this paper a system for 3-D quantitative analysis of human spontaneous intracerebral brain hemorrhage (ICH) is described. The purpose of the developed system is to perform quantitative 3-D measurements of the param...
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In this paper a system for 3-D quantitative analysis of human spontaneous intracerebral brain hemorrhage (ICH) is described. The purpose of the developed system is to perform quantitative 3-D measurements of the parameters of ICH region and from computed tomography (CT) images. The measured parameter in this phase of the system development is volume of the hemorrhage region. The goal of the project is to measure parameters for a large number of patients having ICH and to correlate measured parameters to patient morbidity and mortality.
The UNIX operating system has been extended to support COCANET, a local network under development at the University of California, Berkeley. COCANET is used for research on distributed database systems and provides s...
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The UNIX operating system has been extended to support COCANET, a local network under development at the University of California, Berkeley. COCANET is used for research on distributed database systems and provides shared access to resources available on different computers in the Department of electricalengineering and computerscience. The extensions to UNIX were made to establish access for a user to a distributed network of files in the same manner that standard UNIX provides local access to a user's files. For example, COCANET UNIX extends the file system name space by including the host name. A core-resident message-switching process added to COCANET UNIX made possible the implementation of features added by the extension. Approximately 18 man-months of work went into the development of COCANET UNIX, which was implemented on a PDP 11/70 under UNIX Version 6.
This article was updated to correct Minghao Zhang’s affiliation from "Pritzker School of Molecular engineering, The University of Chicago, Chicago, USA" to "Pritzker School of Molecular engineering, Th...
We examine the problem of broadcasting in a point-to-point computer network where a message, originated by one node, is transmitted to all nodes, subject to the restriction that an informed node can call only one of i...
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We examine the problem of broadcasting in a point-to-point computer network where a message, originated by one node, is transmitted to all nodes, subject to the restriction that an informed node can call only one of its neighbors Auring a given time unit. A dynamic programming formulation for optimal broadcasting in general networks is given, and an exact algorithm based on it is developed. Since this algorithm is not very efficient for larger networks, we present a number of heuristics for achieving efficient near-optimal algorithms. In particular, we discuss in detail a class of heuristics which require finding at each step a least-weight maximum matching in a bipartite graph.
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