• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.394-397
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• 2003

최근의 system 내에서 동작속도가 급속히 증가함에 따라 단일 chip 내에서도 각부분의 clock 동기의 필요성이 요구되고 있다. 이러한 요구를 만족시키기 위해 PLL (Phase Locked Loop) 흑은 DLL (Delay Locked Loop)과 같은 clock를 동기 시켜 주는 회로가 사용되고 있다. PLL 내에서 주파수를 발생시키는 VCO (Voltage Controled Oscillator)는 jitter의 축적과 higher order system으로 인한 unstable한 특성과 설계하기 어렵다는 단점이 있다. 반면에 DLL에서 사용되는 VCDL (Voltage Controled Delay Line)은 first order system으로 동작이 stable하고 설계하기 쉬우며, no jitter의 장점을 가지고 있다. 본 연구에서는 기존의 VCDL의 단점을 개선하여 보다 안정적인 동작을 하는 VCDL을 제안하고자 한다.

• 반도체디스플레이기술학회지
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• 제14권3호
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• pp.27-31
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• 2015

It was the electrical properties of ZnS treated by the annealing in a vaccum and an atmosphere conditions to reseached the leakage current effect of semiconductor devices. Most samples were shown the non-linear with unipolar properties, but the ZnS annealed at $100^{\circ}C$ in a vaccum was only observed no leakage current in a range of -20 V< voltage < 15 V. The crystallinity of ZnS with no leakage current was improved and optical property was also improved. Because the ambipolar characteristics and low leakage currents originated from the extension effect of a depletion width by electron-hole combination in the depletion layer.

• Journal of Ginseng Research
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• 제20권1호
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• pp.7-14
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• 1996

This study was performed to examine the effect of red ginseng total saponin and extract on memory in mice using one trial step-down type passive avoidance method. Red ginseng total saponins (No. 1: PD/PT ratio=1.24, No. 2: PD/PT ratio=1.47) were prepared with the different mixing ratio by using the parts of red ginseng. In single administration of total saponin No. 1 (100 mg/ kg, bw) or No. 2 (50 mg/kg, bw) increased the latency time as compared with control group but was not statistically significant. Treatment of total saponin No. 1 (50 mg/kg, bw) for 10 days produced an increase of latency time but was not statistically significant. In scopolamine-induced memory deficient mice total saponin No. 1 (50 mg/kg, bw) and No. 2 (100 mg/kg, bw) significantly improved the latency time. These results show that red ginseng total saponin may improve the memory of sco-polamine-induced memory deficient mice and have nootropic activity.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.472-475
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• 1999

An improved series-parallel resonant converter using auxiliary winding of resonant is presented. The conventional series-parallel resonan converter and newly developed converter are compared for high voltage application. This proposed converter gives several merits such a wide load ranges, small circulating current, low peak voltage at no load. Two experimental results for the proposed converter and conventional one are presented for conventional LCC type converter and the proposed one.

• 한국항공운항학회:학술대회논문집
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• 한국항공운항학회 2005년도 추계학술발표대회 논문집
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• pp.217-222
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• 2005

• 대한화학회지
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• 제37권11호
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• pp.978-981
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• 1993

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2000년도 학술발표회 논문집
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• pp.997-1002
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• 2000

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• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.140-143
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• 2006

Load/Unload(L/UL) technology includes the benefits, that is, increased areal density, reduced power consumption and improved shock resistance. The main issues of L/UL are no slider-disk contact and no media damage. To make sure L/UL stability, we consider many design parameters in L/UL systems. This paper is focused on disk design parameters through designing a disk bump in outer guard band(OGB). In the case of bump design on the disk, we create a bump by changing bump design parameters as like size and amplitude. From dynamic analysis, we choose optimal bump model with the highest flying height and the longest rising time. When a slider passes over a bump in dynamic system, the slider rise above bump according to bump shape. On the basis of this rising effect on the bump, we apply bump design to classical L/UL system having slider-disk contact possibility. This study is based on the simulation, we finally realize improved slider unloading performance by applying slider dynamic result on unload simulation.

• 전력전자학회논문지
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• 제19권5호
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• pp.470-474
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• 2014

This study proposes an improved synchronization control scheme for a low-cost 400Hz power supply for a no-break power transfer system. In the case of aircraft applications, the 400Hz power supply called ground power units is accepted and used as the external electrical power system during stopovers on ground. A momentary break in the supply occurs when shifting from one power source to another. To allow shifting without a break in the supply, the two power sources are momentarily connected in parallel. The proposed synchronization control is achieved by connecting an existing synchronization bus to the voltage zero-crossing signal of a generator power with discrete logic ICs and analog circuits. Therefore, unlike expensive controllers, such as DSP and CAN, the proposed control scheme is rather simple and may decrease operational cost. The practical feasibility of the proposed control scheme is proven by experimental results.

• Asian-Australasian Journal of Animal Sciences
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• 제7권4호
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• pp.547-554
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• 1994

This paper presents the effects of supplementary feeding and internal parasites on the growth rates of female weaner goats raised under improved management. A completely randomized $3{\times}3{\times}2$ factorial design was used. Factors were genotype (Thai native: TN, 75% TN $\times$ 25% Anglo-Nubian: An and 50% TN $\times$ 50% AN), feeding grazing only, low (1.0% BW/d) and high (1.5% BW/d) supplementation and parasite control (undrenched and drenched). It was shown that native goats had significantly (p<0.05) higher growth rates than did the cross-bred goats from 12-24 weeks of the trial. The growth rate of goats grazing improved pasture depended on the amount of concentrate offered as a supplement. There was no significant difference in growth rates between undrenched and drenched goats. There was no interaction effect on growth rates between the treatments. Drenched goats had significantly (p<0.01) lower egg counts per gram of gastro-intestinal nematode than did undrenched goats. There was no significant difference between the treatments for blood constituents (total protein, haemoglobin, packed cell volume, eosinophils, lymphocytes, monocytes and basophils).