This shows a host DBMS simulator that can simulate directly switching software having embedded SQL on a host computer, not switching systems. Execution files compiled on a host are loaded on the switching system, afte...
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ISBN:
(纸本)0818672250
This shows a host DBMS simulator that can simulate directly switching software having embedded SQL on a host computer, not switching systems. Execution files compiled on a host are loaded on the switching system, after testing on the switching testbed hardware. The testing on the testbed has difficult problems that cannot share more than one user simultaneously and can not test the relationship between two execution files. To solve the restriction, the host DBMS simulator has been developed. This is a simulator that can test execution files on the host without loading to the testbeds or switching systems, and can control simultaneously many query requests generated by multiple users on the same host. In this paper, we propose a DBMS simulator on the host system, and present in detail implementation methods of the simulator.
This paper presents dynamic modeling of flexible link manipulators using artificial neural networks. A state-space representation is considered for a neural identifier. The recurrent network configuration is obtained ...
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This paper presents dynamic modeling of flexible link manipulators using artificial neural networks. A state-space representation is considered for a neural identifier. The recurrent network configuration is obtained by a combination of feedforward network architectures with dynamical elements in the form of stable filters. To guarantee the boundedness of the states, joint PD control is introduced in the system. The method can be considered both as an online identifier that can be used as a basis for designing neural network controllers as well as an off-line learning scheme to compute deflections due to link flexibility for evaluating forward dynamics. The performance of the proposed neural identifier is evaluated by identifying the dynamics of different flexible-link manipulators. To demonstrate the effectiveness of the algorithm, simulation results for a single-link manipulator, a two-link planar manipulator and the Space Station Remote Manipulator System (SSRMS) are presented.
In this paper, implementation and evaluation of a printed circuit board assembly (PCBA) manufacturing system model based on fuzzy colored Petri nets (FCPN) modeling was performed. From the Petri nets simulation result...
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In this paper, implementation and evaluation of a printed circuit board assembly (PCBA) manufacturing system model based on fuzzy colored Petri nets (FCPN) modeling was performed. From the Petri nets simulation results, two contributions were claimed: (1) The successful application of our approach to evaluate systems that consist of complicated concurrent processes with embedded data structures and uncertainty reasoning. (2) An approach in automatic determination of the threshold values in the fuzzy production rules using FCPN. The details of the assembling processes and various manufacturing data were gathered from computer manufacturers located in China. Different resource allocation strategies were introduced in the experiments, and simulation results were obtained. The resources included screen printers, different pick and place machines, infrared soldering machines and component insertion robots. All the experiments were built by using the Petri net tool DESIGN/CPN. A number of hierarchy pages, color sets, places, arcs and transitions representing the PCBA and fuzzy production rules were constructed in the experiments. simulation runs of the Petri nets model were carried out. The result shows that our approach could be used to guide decision-makers in the design and selection of a suitable PCBA manufacturing strategy. Future extension of our work is described.
CUMULVS is a middleware library that provides application programmers with a simple API for describing viewable and steerable fields in large-scale distributed simulations. These descriptions provide the data type, a ...
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CUMULVS is a middleware library that provides application programmers with a simple API for describing viewable and steerable fields in large-scale distributed simulations. These descriptions provide the data type, a logical name of the field/parameter, and the mapping of global indices to local indices (processor and physical storage) for distributed data fields. The CUMULVS infrastructure uses these descriptions to allow an arbitrary number of front-end "viewer" programs to dynamically attach to a running simulation, select one or more fields for visualization, and up-date steerable variables. (Viewer programs can be built using commercial visualization software such as AVS or custom software based on GUI interface builders like Tcl/Tk.) Although these data field descriptions require a small effort on the part of the application programmer, the payoff is a high degree of flexibility for the infrastructure and end-user. This flexibility has allowed us to extend the infrastructure to include "application-directed" checkpointing, where the application determines the essential state that must be saved for a restart. This has the advantage that checkpoints can be smaller and made portable across heterogeneous architectures using the semantic description information that can be included in the checkpoint file.
The proceedings contains 52 papers from the 1997 IEEE internationalconference on Application Specific systems, architectures, and Processors. Topics discussed include: visual computing environment for very large scal...
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The proceedings contains 52 papers from the 1997 IEEE internationalconference on Application Specific systems, architectures, and Processors. Topics discussed include: visual computing environment for very large scale biomolecular modeling;computing with locally interconnected architectures;nonlinear digital filter on a digital signal filtering processor;linear array parallel image processor;massively parallel implementation of the watershed based on cellular automata;Jacobi specific dataflow processor;storage size reduction in embedded multimedia systems;full-search block matching algorithms;image geometrical transformations using an embedded core based processor;and data-interlacing architecture for full-search block-matching algorithm.
During the past decade, the military modeling and simulation (M&S) community has seen the formation of the Defense modeling and simulation Office (DMSO) in the Department of Defense (DoD). Subsequently, many other...
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During the past decade, the military modeling and simulation (M&S) community has seen the formation of the Defense modeling and simulation Office (DMSO) in the Department of Defense (DoD). Subsequently, many other offices have been formed within the Services to be Service focal points for M&S and to coordinate Service domains. Out of this has arisen the awareness of the need and benefits of a standard high level M&S architecture. Despite the current seemingly disparate and large number of architectures, the M&S environment within the DoD will settle down to a small set of modelingsystems that will interoperate. However, does this mean that modeling will be mindless;will interoperability be automatic;will all answers be available to everyone? No, organizations will need to come together and plan their experiments within the chosen M&S architecture (i.e., they will need to Federate). Wright Laboratory and Science Applications international Corporation (SAIC) have worked simulation technology extensively over the years and most recently with the DMSO High-Level Architecture (HLA) and the Joint modeling and simulation System (JMASS). This paper will discuss the issues associated with organizations coming together to build a significant simulation suite, provide an approach to this activity, and share results of two Federating efforts.
The view of processing as an integral part of function suggests that information systems must be embedded into the structure and dynamics of the functions they support. This requires that the architecture of the compu...
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The view of processing as an integral part of function suggests that information systems must be embedded into the structure and dynamics of the functions they support. This requires that the architecture of the computer-based information system be compatible with the structure and dynamics of the organization it supports. In this paper we propose a model-based approach to the development of information systems that uses models of the structure and dynamics of organizations in order to develop effective function support. The proposed approach uses a conceptual tool to model key features of the structure and dynamics of the organization and a methodology that maps such features into the architecture of its supporting information system. A modeling and simulation environment is suggested that includes an extensive model base that can be used for the simulation and analysis of organizational function in addition to its use in systems development.
This paper enables symbolic simulation of systems with large embedded memories. Each memory array is replaced with a behavioral model, where the number of symbolic variables used to characterize the initial state of t...
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ISBN:
(纸本)3540631666
This paper enables symbolic simulation of systems with large embedded memories. Each memory array is replaced with a behavioral model, where the number of symbolic variables used to characterize the initial state of the memory is proportional to the number of memory accesses. The memory state is represented by a list containing entries of the form [c, a, d], where c is a Boolean expression denoting the set of conditions for which the entry is defined, a is an address expression denoting a memory location, and d is a data expression denoting the contents of this location. Address and data expressions are represented as vectors of Boolean expressions. The list interacts with the rest of the circuit by means of a software interface developed as part of the symbolic simulation engine. The interface monitors the control lines of the memory array and translates read and write conditions into accesses to the list. This memory model was also incorporated into the Symbolic Trajectory Evaluation technique for formal verification. Experimental results show that the new model significantly outperforms the transistor level memory model when verifying a simple pipelined data path.
The development of network protocols, especially if designed for use in very large scale networks, generally requires extensive simulation and tests in operational environments to assess their performance and correctn...
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ISBN:
(纸本)3540631011
The development of network protocols, especially if designed for use in very large scale networks, generally requires extensive simulation and tests in operational environments to assess their performance and correctness. Both approaches have limitations: simulation because of possible lack of accuracy in modeling the system (and, especially, traffic generators), tests in operating networks because of the difficulty of setting up and controlling the experimental testbed. In this paper we propose to embed network simulators in operational systems, so as to get the advantages of both simulators and real testbeds. Such simulators can be built with minimal modifications to existing protocol stacks. They work by intercepting communications of the protocol layer under test and simulating the effects of finite queues, bandwidth limitations, communication delays, noisy channels. As a result, experiments can be run on a standalone system, while simulating arbitrarily complex networks. Thanks to the ability of using real traffic generators and protocol implementations, doing experiments becomes as simple as running the desired set of applications on a workstation. An implementation of such a simulator, targeted to TCP and compatible with BSD-derived systems, is available from the author.
Knowledge of the complex molecular structures of living cells is being accumulated at a tremendous rate. Key technologies enabling this success have been high performance computing and powerful molecular graphics appl...
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Knowledge of the complex molecular structures of living cells is being accumulated at a tremendous rate. Key technologies enabling this success have been high performance computing and powerful molecular graphics applications, but the technology is beginning to seriously lag behind challenges posed by the size and number of new structures and by the emerging opportunities in drug design and genetic engineering. A visual computing environment is being developed which permits interactive modeling of biopolymers by linking a 3D molecular graphics program with an efficient molecular dynamics simulation program executed on remote high-performance parallel computers. The system will be ideally suited for distributed computing environments, by utilizing both local 3D graphics facilities and the peak capacity of high-performance computers for the purpose of interactive biomolecular modeling. To create an interactive 3D environment three input methods will be explored: (1) a six degree of freedom `mouse' for controlling the space shared by the model and the user;(2) voice commands monitored through a microphone and recognized by a speech recognition interface;(3) hand gestures, detected through cameras and interpreted using computer vision techniques. Controlling 3D graphics connected to real time simulations and the use of voice with suitable language semantics, as well as hand gestures, promise great benefits for many types of problem solving environments. Our focus on structural biology takes advantage of existing sophisticated software, provides concrete objectives, defines a well-posed domain of tasks and offers a well-developed vocabulary for spoken communication.
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