• Journal of Information Processing Systems
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• v.8 no.2
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• pp.331-346
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• 2012

Task-based programming is becoming the state-of-the-art method of choice for extracting the desired performance from multi-core chips. It expresses a program in terms of lightweight logical tasks rather than heavyweight threads. Intel Threading Building Blocks (TBB) is a task-based parallel programming paradigm for multi-core processors. The performance gain of this paradigm depends to a great extent on the efficiency of its parallel constructs. The parallel overheads incurred by parallel constructs determine the ability for creating large-scale parallel programs, especially in the case of fine-grain parallelism. This paper presents a study of TBB parallelization overheads. For this purpose, a TBB micro-benchmarks suite called TBBench has been developed. We use TBBench to evaluate the parallelization overheads of TBB on different multi-core machines and different compilers. We report in detail in this paper on the relative overheads and analyze the running results.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.5
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• pp.1065-1075
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• 2001

It is common knowledge amongst electrical and marine engineers that short-circuit in electrical system may cause large mechanical torque on generator and prime mover However, it is not so widely known that the faulty synchronizing of generators may cause even higher torques than that of short-circuit. In this study, the transient phenomena related to the parallel running of synchronous generators are analyzed and the exact computer simulation method is proposed. In result, maximum transient torque and current take place in case of $120^{\circ}$ voltage angle difference between Master and Slave and that may develop higher torque than the short-circuit according to a condition of synchronizing. When synchronizing in power system using only two generators higher torque and current occur Master, but using multimachine system those occur to Slave. The short-circuit of marine generator does not happen frequently but faulty synchronizing sometimes takes place, therefore, it is necessary for designers to consider these phenomena.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.503-505
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• 2000

In general, the reason of the abnormal corrosion on oil tanks has been proved the MIC (Microbiologically Influenced Corrosion). The concern about MIC is increasing more and more now days. Therefore, this paper presents the results of basic study on the Microbiologically Influenced Corrosion of gas pipeline running parallel with 22.9kV D/L (Distribution Line).

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.352-359
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• 1999

This paper is a research for removing the alternators hunting which came about during the par-allel running. The four-pole six-phase alternator is equipped with the converter made out of twelve diodes to rectify all the waves. The hunting came about during the battery charging due to the hunting inducing point existed in r. p. m band 1575[rpm-1690[rpm] To remove the hunting inducing point We modified the four-pole six-phase alternator into the four-pole twevel-phase and increased the short-circuit ratio by decreasing the field coil pitch and increasing the field coil turns. But this method has two defects the first the alternator structure becomes complicating and the second the second the alternator equipped with the converter used in general purpose lately such as the car alternator can not be run in parallel wlthout modifying. To remove the defects the equalizing line was connected between the same phase of the alterna-tor to flow the synchronizing current which syncronize the phases of generator electromotive forces by which the alternator can be run in parallel without reference to the hunting inducing point and without modifying.

• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.3
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• pp.13-34
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• 1993

By operating on many part of a software system concurrently, the parallel processing computers may provide several orders of magnitude more computing power than traditional serial computers. If the Lagrangean approximation procedure is applied to a large scale manufacturing problem which is decomposable into many subproblems, the procedure is a perfect candidate for parallel processing. By distributing Lagrangean subproblems for given multiplier to multiple processors, concurrently running processors and modifying Lagrangean multipliers at the end of each iteration of a subgradient method,a parallel processing of a Lagrangean approximation procedure may provide a significant speedup. This purpose of this research is to investigate the potential of the parallelized Lagrangean approximation procedure (PLAP) for certain combinational optimization problems in manufacturing systems. The framework of a Plap is proposed for some combinatorial manufacturing problems which are decomposable into well-structured subproblems. The synchronous PLAP for the multistage dynamic lot-sizing problem is implemented on a parallel computer Alliant FX/4 and its computational experience is reported as a promising application of vector-concurrent computing.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.88-90
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• 2003

We implement Realtime Air Diffusion Prediction System which is designed for air diffusion simulations with four-dimensional data assimilation. For realtime running, we parallelize the system using MPI (Message Passing Interface) on distributed-memory parallel computers and build a cluster computer which links high-performance PCs with high-speed interconnection networks. We use 162­CPU nodes and a Myrinet network for the cluster

• Journal of the Korean Data and Information Science Society
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• v.10 no.2
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• pp.473-483
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• 1999

We introduce a way to construct a supercomputing capable system with some networked PCs, running the Linux operating system and computing power comparable with expensive commercial workstations, and with the Parallel Virtual Machine (PVM) software which enables one to control the total CPUs and memories of the networked PCs. By benchmarking the system using a PVM parallel program, we find that the system's parallel efficiency is close to 90 %.

• The Transactions of the Korea Information Processing Society
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• v.1 no.3
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• pp.290-298
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• 1994

In this paper we propose parallel sorting algorithm, taking 0( $n^{n}$ log n) time complexity, 0( $n^{x}$ log n) cost (parallel running time * number of processors) and 0( $n^{1-}$x＋ $n^{x}$ )data movement complexity under the ERWW- PRAM model. The methods for solving these problems similar. Parallel algorithm finds pivot for partitioning the data into ordered subsets of approximately equal size by using encording pointers..

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.2
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• pp.144-150
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• 2002

In this paper a design of neuro-fuzzy-based predictive controller for nonlinear systems with time-delay is proposed. The proposed control system contains two neuro-fuzzy systems called ANFIS(Adaptive Neuro-Fuzzy Inference System). One is run as a series-parallel mode and the other is run as a parallel mode. An ANFIS running in series-parallel mode emulates the response of the nonlinear system with time-delay. Another ANFIS running in parallel mode generates the predicted output of the nonlinear system to compensate for the time-delays. Therefore, the proposed control system can be thought of as an extension of Smith-predictor scheme to the nonlinear systems with time-delay. A detailed design Procedure is presented and finally computer simulations are executed for the effectiveness of the proposed control scheme.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.529-544
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• 2007

After rapid running is begun in domestic, problem by the train gust that was not considered at existent train running appeared. If the High-Speed railway business speed rises by 350km/h in the future, is going to become more big problem. This study conducts an experiment that measure in local about KTX train beside Gyeong-Bu High speed railroad track about aerodynamics effect that happen by passage of train and analyzed. In case KTX II runs with the 350km/h speed, forecasted effect that get in the simple vertical surfaces parallel to tracks according to distance from rail center. Compared construction size with structural analysis in case do not consider with case that consider the train gust about sound proof walls representatively. As a result, proposed wind load standard that apply at sound proof walls design.