• 전자공학회논문지CI
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• 제44권5호
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• pp.12-19
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• 2007

본 논문에서는 ASIP(Application Specific Instruction-set Processor) 기반의 실시간 H.264/AVC 구현 가능한 VSIP(Video Specific Instruction-set Processor) 을 제안한다. 제안한 VSIP은 H.264/AVC의 화면 내 예측, 디블록킹 필터, 정수 변환 등 새로운 기능들을 효율적으로 지원하기 위한 전용의 하드웨어 구조와 명령어를 가지고 있다. 또한 화면 간 예측 및 엔트로피 코딩과 같이 연산량이 많은 부분은 하드웨어 가속기로 만들어 연산 처리 속도 및 효율을 높였다. VSIP은 H.264/AVC에 적합한 하드웨어 구조와 명령어를 통해 기존의 디지털 신호처리 프로세서보다 작은 크기를 가지며, 메모리 접근 횟수를 줄여 전력 소비를 감소시켰다. 제안한 VSIP을 이용하여 실시간 영상 신호처리를 할 수 있으며, 다양한 프로파일과 표준을 지원할 수 있다.

• KEPCO Journal on Electric Power and Energy
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• 제1권1호
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• pp.99-104
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• 2015

In this study, it has been initiated to investigate the specific abnormal vibration signal that has been captured in the power equipment. Array Microphone can be used in order to detect the direction and the position of the noise source. It is possible to track the abnormal mechanical noise in the power plant by utilizing the program and the microphone array system developed from this research. Array microphone system can be operated as a constant monitoring system.

• KIEE International Transactions on Power Engineering
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• 제5A권3호
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• pp.280-285
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• 2005

This paper proposes a novel method for determining the kind and rating of power quality solutions. To determine the kind of solution, event cause and direction are utilized. According to the event cause and direction, an adequate type of solution is determined for effective compensation. To rate the required capacity of solution, the concept of lost energy is adopted. Lost voltage, lost power and lost energy are calculated and the rating of the solution is determined to compensate a specific event. The rating method that utilizes the result of stochastic diagnosis is also proposed. A power quality index such as CP95 is adopted for solution suggestion. The method developed in this paper is applied to the test system and proved to be useful for enhancing the power quality of the customer system. It can provide customers with information pertaining to what is a proper and cost-effective solution among various compensating devices.

• 전기저널
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• 10호통권166호
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• pp.7-11
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• 1990

• Korean Journal of Acupuncture
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• 제24권2호
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• pp.193-216
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• 2007

Objectives : The aim of this study was to examine the effect of electroacupuncture (EA) at the PC8 on normal human beings by using power spectral analysis. Methods : EEG (Electroencephalogram) power spectrum exhibits site-specific and state-related differences in specific frequency bands. In this study, power spectrum was used as a measure of complexity. 32 channels EEG study was carried out in 20 subjects (20 males; age=26.8 years old). Results : In ${\alpha}(alpha)$ band, the power values at F7, F8, P3 channels(p<0.05) during the $PC_8-acupoint$ treatment significantly decreased. In ${\beta}(beta)$ band, the power values at F4, F8, P3 channels(P<0.05) during the PC8-acupoint treatment significantly decreased. In ${\delta}(delta)$ band, the power values at F7, F8, P3 Po2 channels(p<0.05) during the $PC_8-acupoint$ treatment significantly decreased. In ${\theta}(theta)$ band, the power values at F7, Fz, F4 F8, FTC1, FTC2, CP2, TT2, P3, Pz, Po2 channels(p<0.05) during the PC8-acupoint treatment significantly decreased. Conclusions : This results suggest that Electroacupuncture at the PC8 mostly affect the change on theta(11 channels) bands.

• KEPCO Journal on Electric Power and Energy
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• 제7권2호
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• pp.329-333
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• 2021

V2G (Vehicle to Grid) technology for an EV (Electric Vehicle) has been assumed as so promising in a near future for its useful energy resource concept but still yet to be developed around the world for specific service purposes through various R&BD projects. Basically, V2G returns power stored in vehicle at a cheaper or unused time to the grid at more expensive or highly peaked time, and is accordingly supposed to provide such roles like peak shaving or load levelling according to customer load curve, frequency regulation or ancillary reserves, and balancing power fluctuation to grid from the weather-sensitive renewable sources like wind or solar generations. However, it has recently been debated over its prominent usage as diffusing EVs and the required charging/discharging infrastructure, partially for its addition of EV ownership costs with more frequent charging/discharging events and user inconvenience with a relative long-time participation in the previously engaged V2G program. This study suggests that a Korean DR (Demand Response) service integrated V2G system especially based upon a dynamic charge/pause/discharge scheme newly proposed to ISO/IEC 15118 rev. 2 can deal with these concerns with more profitable business model, while fully making up for the additional component (ex. battery) and service costs. It also indicates that the optimum economic, environmental, and grid impacts can be simulated for this V2G-DR service particularly designed for EV aggregators (V2G service providers) by proposing a specific V2G engagement program for the mediated DR service providers and the distributed EV owners.

• 한국환경보건학회지
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• 제36권2호
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• pp.128-135
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• 2010

The main purpose of this study was to develop the greenhouse gas emission factor for power plant using sub-bituminous coal. In Korea, Fired power plant are a major source of greenhouse gases within the fossil fuel combustion sectors, thus the development of emission factors is necessary to understand the characteristics of the national specific greenhouse gas emission and to develop nation specific emission factors. These emission factors were derived from the $CO_2$ concentrations measurement from stack and fuel analysis of sub-bituminous coal. Caloric value of sub-bituminous coal used in the power plants were 5,264 (as received basis), 5,936 (air-dried basis) and 6,575 kcal/kg (dry basis). The C emission factors by fuel analysis and $CO_2$ concentration measurement was estimated to be 26.7(${\pm}0.9$), 26.3(${\pm}2.8$)tC/MJ, respectively. Our estimates of C emission factors were comparable with IPCC default value.

• 전기학회논문지
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• 제59권1호
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• pp.33-39
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• 2010

In order to operate the power system satisfactory for both system operators and customers, it is important to limit the harmonic currents to the allowable levels which injected into the system from the distorting installations. In this regard, the principles for the allocation of emission limits on individual customer were introduced in the technical report of IEC61000-3-6. According to these general principles, the emission limits are dependent on the agreed power of the customer, the power of the harmonic-generating equipment, and the system characteristics. The considerations in this report are very comprehensive and the process introduced is practical enough to implement as it is. However, there is a fact not appropriately dealing in the report that could be a very tickle but has a huge impact on determining the emission limit. This is the effect of non-harmonic load currents. More precisely, these are from the equipments which do not emit any harmonic or may emit harmonics but this specific order under the consideration by themselves if the source power is sinusoidal. The load currents originated from these equipments have an effect of active filter against the specific order of harmonic therefore, these should be dealt as a significant factoron the process of determining the emission limits for individual customer.

• 농업과학연구
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• 제31권1호
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• pp.26-34
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• 2004

In this study, motion characteristics and power requirement of rotary tilling according to shape of conventional rotary blade were measured. This study was performed to establish factors which needed to develop energy saving rotary blade. Starting point of edged curve of imported rotary blade was faster than that of domestic rotary blade after measuring and analyzing edged curve of rotary blade. So domestic rotary blade tills much soil than imported rotary blade. In analyzing motion of rotary blade, Rotary blade of A, D type was begun to contact at part 3. Analyzing back surface of rotary blade which contact to soil at critical $\lambda$ results in contacting at e-f part. In measuring power requirement of rotary blade, specific torque and specific work of rotary blade are $160{\sim}170kgf{\cdot}m/m^2$, $3,700kgf{\cdot}m/m^3$. It shows power requirement of rotary blade according to shape of rotary blade are very different.

• Journal of Biosystems Engineering
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• 제37권6호
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• pp.385-397
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• 2012

Purpose: Drying characteristics of sawdust was studied under batch mode using lab scale microwave dryer. The objective of this study was to investigate the effect of material load and microwave output power on drying characteristics of sawdust. Methods: Material load and microwave output power were varied from 23 to 186 g and 530 to 370 W respectively. Different kinetic models were tested to fit the drying rates of sawdust. Similarly, the activation energy was calculated by employing the Arrhenius equation. Results: The drying efficiency increased considerably, whereas the specific energy consumption significantly decreased with increase in material load and microwave output power. The cumulative energy efficiency increased by 9%, and the specific energy consumption decreased by 8% when the material load was increased from 23 to 186 g. The effective diffusivity increased with decrease in material load and increase in microwave output power. The previously published model gave the best fit for data points with $R^2$ and RMSE values of 0.999 and 0.01, respectively. Conclusions: The data obtained from this study could be used as a basis for modeling of large scale industrial microwave dryers for the pellet production.