• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.901-915
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• 1999

Parallel computers are known to be excellent in performance per cost also satisfying scalability and high performance. However parallel machines have enjoyed limited success because of difficulty in parallel programming and non-portability between parallel machines. Recently, researchers have sought to develop data parallel language that provides machine independent programming systems. Data parallel language such as High Performance Fortran provides a basis to write a parallel program based on a global name space by partitioning data and computation, generating message-passing function. In this paper, we describe the Parallel Programming Translator(PPTran), source-to-source data parallel compiler, generating MPI SPMD parallel program from HPF input program through four phases such as data dependence analysis, partitioning data, partitioning computation, and code generation with explicit message-passing and verify the performance of PPTran

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.555-560
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• 2003

Korean High Speed Train(KHST) has been tested on the high speed test line in Osung site of Korea High Speed Rail Construction Authority (KHRC). since it was developed as G7 Project Plan In 2002. This paper introduces the dynamic test devices in KHST and shows the comparison between the results of test and theoretical computing results which derive from the new model for KHST dynamic behavior. Previous computer simulation model for KHST was developed to review wether the vehicle system was satisfied with the dynamic performance requirements during the design procedure. But It should be applied the results of the parts test for suspension elements in order to compare between the results of computation and real test. Using VAMPIRE Program made by AEA Technology in UK. the new model also was modified. This paper shows that the static wheel loads calculated from new model is similar to test results. For test on high speed line, we prepared the test devices for evaluating the dynamic performances. which was consisted of the accelerometers( based on Kisler Co.) and the data aquisition systems (based on National instrument Co.), and test program coded by LabView 6i program. These lest devices and programs are flexible to extension the channels for adding sensors and connect to the ethernet network. The acceleration of car bodies, bogie frames and axle boxes were compared between the results of computation and test at 150km/. This paper shows that the results of test were high in high frequency band range but similar frequency band range. It might be considered that these differences were caused by the test which did not performed at constant speed for comparison analysis. Also. It will be able to understand the differences and make better results through a lot of tests planed in future.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.3
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• pp.143-153
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• 1998

In this reaserch, a program for real time simulation of a vehicle is developed. This program uses relative coordinates to save the computation time and BDF(Backward Difference Formula) to integrate system variables. Numerical tests were performed for J-turn and Lane change steering, respectively. The validity of the program is proved by the ADAMS package. Numerical results showed that the proposed implicit method is more stable in carrying out the numerical integration for vehicle dynamics than the explicit method. Hardware requirements for real time simulation are suggested.

• The Journal of Korean Society for Radiation Therapy
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• v.11 no.1
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• pp.28-32
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• 1999

Verifying the treatment value(Monitor Unit) unnecessarily involves too many simple and repetitive calculation processes, that is, individual computation process using the data(PDD value, Scp Factor, SSD Factor, Tray Factor) on the data book. We intend to minimize the time required to check the Monitor Unit through computerized calculation. Using $^{\ast}(multiplication)$, /(division), +(sum), if function, among others, which are present in the Excell program, MS office program, the Monitor Unit was obtainable through A/P value, Scp Factor and PDD value, Wedge Factor. From the verification of the computations of Monitor Unit for 60 patients previously treated, we were able to obtain an error rate of ${\pm}0.028MU$. Computerized calculation of the Monitor Unit could save the burden of Technologist.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.299-310
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• 1998

Actually mixed assembly line is mixed with open and close type workstation. This workstation is called hybridworkstation. The propose of this paper is to determine the sequencing of model that minimize line length for actual(hybridworkstation) mixed model assembly line. we developed three mathematical formulation of the problem to minimize the overall length of a line with hybrid station. Mathematical formulation classified model by operato schedule. Mixed model assembly line is combination program and NP-hard program. Thus computation time is often a critical factor in choosing a method of determining the sequence. This study suggests a tabu search technique which can provide a near optimal solution in real time and use the hill climbing heuristic method for selecting initial solution. Modified tabu search method is compared with MIP(Mixed Integer Program). Numerical results are reported to demonstrate the efficiency of the method.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.297-299
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• 1999

The B-coefficient method is well-known and universally used method for its simplicity and computation speed. However, the B-coefficient method has a weak point of accuracy when it is applied to the ill-conditioned systems where generators produce excessive reactive power. This paper describes the developed module to be applied to commercial program package of calculating the penalty factors by Jacobian method. The effectiveness of the proposed program has been demonstrated using the IEEE 30 bus system.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1880-1884
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• 2007

The Natural Resource Conservation Service Curve Number(NRCS-CN) method is one of the widely used methods for computation of runoff from a basin. However, NRCS-CN method has weak point in that the spatial land use distribution characteristics are ignored by using area weighted CN value. This study developed a program which can estimate runoff by considering spatial distribution of CN and flow accumulation at the outlet of the watershed by appling Moglen's method. Comparisons between the results from NRCS-CN method and this study showed good agreement with measured data of experimental watersheds. The developed program predicted lower runoff than the conventional NRCS-CN method. As a conclusion, this study proposes a new design direction which can simulate real runoff phenomena. And the developed program could be applied into runoff minimization design for a basin development.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.12
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• pp.1902-1918
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• 1993

Parallel architecture based on the von Neumann computation model has a limitation as a massively parallel architecture due to its inherent drawback of architectural features. The data-flow model of computation has a high programmability in software perspective and high scalability in hardware perspective. However, the practical programming and experimentaion of date-flow architectures are hardly available due to the absence of practical data-flow, we present a programming environment for performing the data-flow computation on conventional parallel machines in general, loosely compled multiprocessor system in particular. We build an emulator for tagged token data-flow architecture on the iPSC/2 hypercube, a loosely coupled multiprocessor system. The emulator is a shallow layer of software executing on an iPSC/2 system, and thus makes the iPSC/2 system work as a data-flow architecture from the programmer`s viewpoint. We implement various numerical and non-numerical algorithm in a data-flow assembler language, and then compare the performance of the program with those of the versions of conventional C language, Consequently, We verify the effectiveness of this programming environment based on the emulator in experimenting the data-flow computation on a conventional parallel machine.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.109-117
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• 2010

To enable high-performance computing (HPC) for applications with large datasets using a $Sony^{(R)}$ $PLAYSTATION^{(R)}$ 3 ($PS3^{TM}$) video game console, we configured a hybrid system consisting of a $Windows^{(R)}$ PC and a $PS3^{TM}$. To validate this system, we implemented the real-time multiplet identifier (RTMI) application, which identifies multiplets of microearthquakes in terms of the similarity of their waveforms. The cross-correlation computation, which is a core algorithm of the RTMI application, was optimised for the $PS3^{TM}$ platform, while the rest of the computation, including data input and output remained on the PC. With this configuration, the core part of the algorithm ran 69 times faster than the original program, accelerating total computation speed more than five times. As a result, the system processed up to 2100 total microseismic events, whereas the original implementation had a limit of 400 events. These results indicate that this system enables high-performance computing for large datasets using the $PS3^{TM}$, as long as data transfer time is negligible compared with computation time.

• Journal of Digital Contents Society
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• v.14 no.1
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• pp.65-72
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• 2013

Current and future parallel computing model has been suggested for running and solving large-scale application problems such as climate, bio, cryptology, and astronomy, etc. Parallel computing is a form of computation in which many calculations are carried out simultaneously. And we are able to shorten the execution time of the program, as well as can extend the scale of the problem that can be solved. In this paper, we perform the actual cryptographic algorithms through parallel processing and evaluate its efficiency. Length of the key, which is stable criterion of cryptographic algorithm, judged according to the amount of complete enumeration computation. So we present a detailed procedure of DES key search cryptographic algorithms for executing of enumeration computation in parallel processing environment. And then, we did the simulation through applying to clustering system. As a result, we can measure the safety and solidity of cryptographic algorithm.