This issue of Computer is based on two workshops in distributed processing held at Brown University August 17-19, 1976, and August 3-5, 1977. Sponsored by the Army Research Office, the National Science Foundation, and...
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This issue of Computer is based on two workshops in distributed processing held at Brown University August 17-19, 1976, and August 3-5, 1977. Sponsored by the Army Research Office, the National Science Foundation, and the Office of Naval Research, the workshops attempted to define what distributed processing means and to develop a taxonomy of distributed processing applications and techniques. Achievements to date and outstanding research problems were examined in an attempt to find either commonality of problems and solutions or substantial differences.
There is a need for distributed processing that enables large-scale data processing, such as web applications. On the other hand, in order to improve the scalability and small-start nature of session control server pr...
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ISBN:
(数字)9798331521165
ISBN:
(纸本)9798331521172
There is a need for distributed processing that enables large-scale data processing, such as web applications. On the other hand, in order to improve the scalability and small-start nature of session control server provided by communication carriers, a data distribution management method using microservices architecture is established. Practical evaluation and verification conditions were applied to the simulation, and the effectiveness is evaluated and confirmed.
The sequential branch and bound algorithm is the most established method for solving mixed integer and discrete programming problems. It is based on the tree search of the possible subproblems of the original problem....
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The sequential branch and bound algorithm is the most established method for solving mixed integer and discrete programming problems. It is based on the tree search of the possible subproblems of the original problem. There are two goals in carrying out a tree search, namely, (i) finding a good and ultimately the best integer solution, and (ii) to prove that the best solution has been found or no integer feasible solution exists. We call these the stage 1 and stage 2 of tree search. In general it is extremely difficult to choose the ideal search strategy in stage 1 or stage 2 for a given integer programming (IP) problem. On the other hand by investigating a number of different strategies (and hence different search trees) a good solution can be reached quickly in respect of many practical IP problems. Starting from this observation a parallel branch and bound algorithm has been designed which exploits this two stage approach. In the first stage we investigate a number of alternative search trees (forest search) in the hope of finding a good solution quickly. This we call the multiple heuristic search (MHS). In this approach the best integer solution is broadcast to other processors involved in MHS tree development. In the second stage we reorganise the search to investigate branches of a chosen tree in parallel. This two stage algorithm has been implemented on a cluster of SUN workstations using the Parallel Virtual Machine (PVM) harness [12]. The results of our investigation for a range of well known test problems taken from the MIPLIB set and others from the literature are reported here.
The emergence and widespread availability of network computing have made it possible for many computationally intensive applications to take advantage of distributing processing techniques at almost no additional cost...
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The emergence and widespread availability of network computing have made it possible for many computationally intensive applications to take advantage of distributing processing techniques at almost no additional cost. In this paper, we present a successful implementation of distributed processing for screening all possible single contingencies in an electric network model. The implementation is based on the remote execution model that is available in most UNIX based workstations, Our testing results show that near ideal speedups can be achieved for the contingency screening applications.
This paper describes the design, implementation, and application examples of PLATINA, a distributed processing platform for telecommunication software. PLATINA is based on the distributed concurrent object-oriented pa...
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This paper describes the design, implementation, and application examples of PLATINA, a distributed processing platform for telecommunication software. PLATINA is based on the distributed concurrent object-oriented paradigm. This enhances the transportability and extensibility of the telecommunication software on distributed telecommunication nodes and provides high performance with little increase in execution overhead. We can easily implement enhanced telecommunication services, which utilize high-speed and wide-band networks and satisfy the various requirements for the services, by cooperative execution of objects distributed over the nodes with PLATINA. PLATINA provides test facilities suitable for the distributed objects and allows easy testing of enhanced telecommunication service software.
This paper surveys some of the issues involved in building useful distributed systems involving PC's and hosts. Alternative communications techniques for micro-mainframe communication are compared. The point of vi...
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This paper surveys some of the issues involved in building useful distributed systems involving PC's and hosts. Alternative communications techniques for micro-mainframe communication are compared. The point of view is presented that the PC user should be provided with a unified view of the heterogeneous distributed system to which he is connected. The proposed method is to formalize the notion of a service request and provide distributed services by function shipping service requests to remote nodes able to provide the service, e.g., personal computers will ship requests which they cannot satisfy locally to hosts on the network. Providing a unified view of data which allows PC application programs to access files on mainframes is an example of a service which can be built by intercepting and shipping service requests. Examples from current IBM products are used to illustrate approaches. The views presented are the authors' own, based on systems research in progress at the IBM Thomas J. Watson Research Center.
Orthogonal frequency-division multiplexing with index modulation (OFDM-IM) has become a high-profile modulation scheme for the fifth-generation (5G) wireless communications and has thus been extended to multi-hop scen...
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Orthogonal frequency-division multiplexing with index modulation (OFDM-IM) has become a high-profile modulation scheme for the fifth-generation (5G) wireless communications and has thus been extended to multi-hop scenarios in order to improve the network coverage and energy efficiency. However, the extension of OFDM-IM to multi-relay cooperative networks is not trivial, since it is required that a complete OFDM block should be received and decoded as an entity in one node. This requirement prevents the employment of multiple relays to forward fragmented OFDM blocks on individual subcarriers. In this regard, we propose a distributed processing scheme for multi-relay assisted OFDM-IM, by which multiple relays are selected to forward signals in a per-subcarrier manner to provide optimal error performance for two-hop decode-and-forward (DF) OFDM-IM systems. Specifically, a single selected relay only needs to decode partial information carried on certain active subcarriers and forward just as for traditional OFDM systems without IM. After receiving all signals on active subcarriers forwarded by different relays, the destination can reconstruct the complete OFDM block and retrieve the full information. We analyze the average block error rate and modulation capacity of the two-hop OFDM-IM system employing the proposed distributed DF protocol and verify the analysis by numerical simulations.
Ocean data exhibits interesting yet human critical features affecting all creatures around the world. Studies on Hydrology and Oceanology become the root of many disciplines, including global resource management, macr...
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Ocean data exhibits interesting yet human critical features affecting all creatures around the world. Studies on Hydrology and Oceanology become the root of many disciplines, including global resource management, macro economy, environment protection, climate predictions, etc, which motivates our further exploration on the underlying feature behind the ocean data. However, with high dimensionality, large quantities, heterogeneous sources, and especially, the spatiotemporal manner, the diversity between the specific knowledge required and massive data chunk puts forward unique challenges in data representation and knowledge mining, effectively. This paper tends to provide a summary of studies on these issues, including the data representation, data processing, knowledge discovery, and algorithms on finding unique patterns on ocean environment changes, such as temperature, tide height, waves, salinity, etc. In detail, we comprehensively discuss about ocean spatiotemporal data processing techniques. We further summarize related representation works on ocean spatiotemporal data, the construction of a ocean knowledge graph, and the management of ocean spatiotemporal data. At last, we combine and compare the collection of the evolution and multiple state-of-the-arts on ocean spatiotemporal data processing.
Hospitals deal with large amounts of data, which need to be accesed by different internal departments, each with its own particular needs. When information is passed within a District Health Authority from hospital to...
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Hospitals deal with large amounts of data, which need to be accesed by different internal departments, each with its own particular needs. When information is passed within a District Health Authority from hospital to hospital the situation is more complex. A network in a major London hospital with external links is described with particular emphasis on its evolution and the need for versatility with cost effectiveness. Future plans are also discussed.
In this work we analyze the problem of an optimal distribution of a computational task among a set of processors. We assume that the task can be arbitrarily divided and its parts can be processed in parallel on differ...
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In this work we analyze the problem of an optimal distribution of a computational task among a set of processors. We assume that the task can be arbitrarily divided and its parts can be processed in parallel on different processors. A wide range of interconnection architectures of distributed computer systems is taken into consideration: a chain, a loop, a tree, a star of processors, a set of processors using shared buses, and a hypercube of processors. It is assumed that the communication time is equal to some startup value plus some amount proportional to the volume of transferred data. Using a uniform methodology we present a method to find the distribution of the load so that the minimum completion time is achieved for the considered data distribution scheme. The results can also be used to find such parameters of the processor network as equivalent speed, speedup and utilization. Moreover, the methodology presented here can be a model of the application roll-in time, and can be applied in load balancing in a heterogeneous multiprocessor system.
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