• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.84-89
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• 2000

Thermal simulation of typical stack-type and newly proposed planar-type micro-gas sensors were studied by FEM method. The thermal analyses for the proposed planar structure including temperatur distribution over the sensing layer and power consumption of the heater were carried using finite element method by computer simulation and well compared with those of typical stack-type micro-gas sensor. The thermal properties of the microsensor from thermal simulation were compared with those of a actual device to investigate the acceptability of the computer simulation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.539-541
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• 2013

울산 신항 남항지구에 설치되는 SPM은 설치 위치와 공사의 특성상 제4항로 전면을 일정 기간 잠식함과 더불어 상당히 광범위한 공사구간이 요구됨으로써 제4항로 통항 선박 및 공사구간을 통항하는 선박들의 통항 안전 및 작업선들의 작업 안전에 대한 대책 마련이 필요한 바 이 연구에서는 제4항로의 임시항로 설정과 임시항로의 통항안전성 평가가 더불어 통항 선박 및 작업선의 해상교통 안전대책을 수립하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.41-42
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• 2009

현재 많은 임베디드 SoC(System-On-Chip)에는 캐시 메모리의 단점을 보완하기 위해 온-칩(On-Chip) SRAM, 즉, SPM(Scratchpad Memory)를 내장하고 있으며 SPM은 그 특성상 캐시 메모리와 달리 소프트웨어가 직접 관리해야 한다. 본 논문에서는 NUMA를 지원하는 Linux 상에서 이식성이 높으면서 단순하게 구현할 수 있는 SPM 관리 방법을 제안한다.

• Journal of electromagnetic engineering and science
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• v.3 no.2
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• pp.79-85
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• 2003

In this paper, we investigated the degree of compensation for distorted optical pulse of wavelength division multiplexed(WDM) channel with initial frequency chirp generated in optical transmitter. The WDM channel signal distortion is due to chromatic dispersion, self phase modulation(SPM) and cross phase modulation(XPM) in fiber. The considered system is 3 ${\times}$ 40 Gbps intensity modulation direct detection(IM/DD) WDM transmission systems, which adopted mid-span spectral inversion(MSSI) as compensation method. We confirmed that the effect of initial frequency chirp on compensation for signal distortion due to a SPM is gradually decreased as a dispersion coefficient of fiber becomes gradually small. But, in the aspect of a compensation for signal distortion due to both SPM and XPM, the effect of initial frequency chirp on compensation is gradually decreased as a dispersion coefficient of fiber becomes gradually large.

• Journal of Computing Science and Engineering
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• v.9 no.2
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• pp.51-72
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• 2015

Time predictability is crucial in hard real-time and safety-critical systems. Cache memories, while useful for improving the average-case memory performance, are not time predictable, especially when they are shared in multicore processors. To achieve time predictability while minimizing the impact on performance, this paper explores several time-predictable scratch-pad memory (SPM) based architectures for multicore processors. To support these architectures, we propose the dynamic memory objects allocation based partition, the static allocation based partition, and the static allocation based priority L2 SPM strategy to retain the characteristic of time predictability while attempting to maximize the performance and energy efficiency. The SPM based multicore architectural design and the related allocation methods thus form a comprehensive solution to hard real-time multicore based computing. Our experimental results indicate the strengths and weaknesses of each proposed architecture and the allocation method, which offers interesting on-chip memory design options to enable multicore platforms for hard real-time systems.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.4
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• pp.47-53
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• 2001

This study is to investigate the problem of the SPM(Skin Pass Mil7) system which is a finishing treatment of steel sheet. and to develop a PID control scheme to minimize process instability. An electrohydraulic servo system with conventional proportional controller used to regulate the force on the strip works inadequately to yield very undesirable transient responses at the moments welding parts of the strip conte into and pass through the rolls. Both linearized and nonlinear models of a typical SPM system ware simulated first by using Simulink. Then Ziegler-Nichols ultimate cycling method was used for an initial reference guide to tune PID gains, and further fine tuning was performed to get desirable response. The test result in the plant show that proposed PID control scheme successfully improves the process instability in a SPM system.

• Tribology and Lubricants
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• v.17 no.3
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• pp.191-197
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• 2001

Nano adhesion and friction characteristics between SPM(scanning electron microscope) tips and flat plates of different materials were experimentally studied. Tests were performed to measure adhesion and friction in AFM(atomic force microscope) and LFM(lateral force microscope) modes in different conditions of relative humidity. Three different Si$_3$N$_4$ tips (rdaii : 15nm, 22nm and 50 nm) and three different flat plates of Si-wafer(100), W-DLC(tungsten-incorporated diamond-like carbon) and DLC were used. Results generally showed that adhesion and friction increased with the tip radius, and W-DLC and DLC surfaces were superior to Si-wafer. But the adhesion force of Si-wafer showed non linearity with the tip radius while W-DLC and DLC surfaces showed good correlation to the “JKR model”. It was found that high adhesion force between Si-wafer and a large radius of tip was caused by a capillary action due to the condensed water.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.461-462
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• 2006

This paper reports on the development of a scanning probe microscopy(SPM) tip with caborn nanotubes. We used an electric field which causes dielectrophoresis(DEP), to align and deposit CNTs on a metal-coated SPM tip. Using the CNT attached SPM tip, we have obtained an enhanced resolution and wear property compared to that from the bare silicon tip through the scanning of the surface of the bio materials. The carbon nanotube tip align toward the source of the ion beam allowing their orientation to be changed at precise angles. By this technique, metal coated carbon nanotube tips that are several micrometer in length are prepared for scanning probe microscopy.

• Journal of Magnetics
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• v.15 no.1
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• pp.36-39
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• 2010

The multi-degrees of freedom surface permanent-magnet motor (Multi-D.O.F. SPM) has several degrees of freedom operations that are defined as the "roll", "yaw", and "pitch". Normally, the torque that is generated to rotate a rotor includes ripples. The analysis of the torque ripples is important for improving motor performance. In terms of the electric analysis, torque ripple occurs as a result of many factors, including the rotor and stator structures, the distribution of the air-gap flux density, and the waveform of the current in the coils. In particular, the torque ripple is an important factor in the stable operation of the Multi-D.O.F. SPM. Therefore, in this work, the torque ripple was analyzed using various types of magnetization for the permanent magnet. An improved model was proposed for the Multi-D.O.F. SPM based on this analysis.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.04a
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• pp.9-25
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• 2001

Fairchild has been developing a new class IPM called SPM consisting of dramatic Packaging technology to achieve the lowest cost rind better performance for low power home appliances and industrial AC drive applications. The first Fairchild SPM development with IGBT 600V/15A for washing machine application started in 1999 and was completed successfully. Fairchild SPMs are going to be the best solution for low power inverter-driven AC drive system after 2001. The new SPM Packages like SPM ∥ and SPIM for the next generation IPM with the highest competitiveness (cost & performance) shall be continuouslly developed.