• 대한전자공학회논문지TC
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• 제49권7호
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• pp.1-5
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• 2012

자기 저장장치의 한계가 보이는 현 시점에서 홀로그래픽 저장장치는 빠른 데이터 전송율과 높은 기록밀도를 가지고 차세대 광 저장장치의 매력적인 후보로 떠오르고 있다. 본 논문에서는 HDSS (Holographic data storage system)의 채널 환경에서 발생하는 2차원 심볼간 간섭효과와 픽셀 어긋남 문제로 인해 발생하는 비트 오검출 문제를 효율적으로 해결하기 위해서 축약 사상 이론 (contraction mapping theorem) 기반의 반복 2차원 등화 기법을 제안한다. 제안하는 기법의 성능을 평가하기 위해 다양한 홀로그래픽 채널 환경을 구성하고 모의 실험을 수행하여 제안하는 기법의 BER 성능을 측정하여 기존의 threshold detection 기법과 비교함으로써 제안 기법의 우수성을 확인하였다.

• 한국수소및신에너지학회논문집
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• 제30권1호
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• pp.43-48
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• 2019

This study investigates the electrochemical characteristics of the hybrid cell that combined the advantageous characteristics of Li secondary battery and supercapacitor, high energy density and high power density, respectively. Electrochemical behaviors of the hybrid cell was characterized by charge/discharge, cycle and impedance tests. The hybrid cell using Li secondary battery and supercapacitor had better discharge capacity and cycle performance than that of using Li secondary battery only. Proper design of such a hybrid cell system is expected to result in substantial benefits to the well being of the Li secondary battery. The hybrid cell involving Li secondary battery for high energy density and supercapacitor for high power density may be the possible solution for future energy storage system.

• 조명전기설비학회논문지
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• 제28권9호
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• pp.60-66
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• 2014

In case of DC railway, value of ESS(Energy Storage System) is already approved. Whereas AC railway system, there are a lot of differences such as system design and operation pattern. Therefore there is doubt about AC ESS usefulness. Especially, regenerative energy can return to the source. So in case of AC 25kV system, it is necessary to consider different operation algorithm compare to DC railway system. In this paper ESS which is installed in AC high-speed railway was introduced. Power consumption pattern of High speed trains were analyzed, proper storage material was reviewed and operation algorithm was suggested. Super capacitor and Battery was used with hybrid type. Super capacitor was used to handle short term energy movement because of its prompt response and battery was used to handle long term energy movement because of its high energy density. Also in case of operation algorithm, phase control method was upgraded compare to voltage magnitude detection method.

• 정보저장시스템학회논문집
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• 제2권4호
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• pp.240-244
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• 2006

As high-definition television(HDTV) broadcasting becoming more generalized, there have been many researches and developments about a large storage capacity and a fast data transfer rate in optical disk drives (ODD). Pickup actuators must have high flexible mode frequencies and large gain margins. Flexible modes are caused by the flexibility of moving parts in the actuator and a servo bandwidth is limited by them. As a result, the system becomes unstable for high-speed operations in high density reading and recording. In this paper, we suggest improved modeling method in considering of the bonding layer. And, the flexible mode frequency of actuator is improved by Design of Experiments of lens holder. The Magnet circuit is designed considering the relation with the moving part. Through improving the yoke design, the magnetic flux is changed and the DC tilt is reduced. Consequently, we designed an actuator which has a high flexible mode frequency and a large gain margins.

• 한국식품과학회지
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• 제23권2호
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• pp.133-140
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• 1991

잎상추(Lactuca sativa L.) 저장 중 재배적요인(품종 및 재배시기) 및 저장요인(저온 및 high-density polyethylene film 포장)이 저장수명 및 품질에 미치는 영향을 구명하기 위하여 생체중량 감소, 외관품위, 황화, 클로로필 및 카로티노이드 함량, 비타민 C 및 nitrate 함량을 조사하였다. 생체중량 감소 및 외관품위의 열화는 포장처리에 의해, 그리고 $4{\sim}5^{\circ}C$ 보다는 $0{\sim}1^{\circ}C$가 더 억제 되었다. 품종간 비교에서는 "적축면" 보다는 "청치마"에서, 그리고 재배시기별 비교에서는 가을재배 보다는 겨울재배에서 이들의 변화가 다소 지연되었다. 저장 중 잎상추의 황화현상은 카로티노이드 함량변화 보다는 주로 클로로필의 파괴 때문이었다. Vitamin C의 저장 전 함량은 "적축면" 보다는 "청치마"에서, 그리고 가을재배 보다는 겨울재배 시 많은 양을 함유하고 있었다. 저장 중 비타민 C는 저장 초기부터 전처리구에서 급격히 감소하였으나, $4{\sim}5^{\circ}C$에 비해 $0{\sim}1^{\circ}C$에서 감소가 다소 지연되었다. Nitrate의 경우는 저장 전 함량은 "적축면"은 3812.6 ppm을 함유하고 있었고, "청치마"는 2856.6 ppm을 함유하고 있었다. 저장 중 nitrate 함량변화는 $4{\sim}5^{\circ}C$에 비해 $0{\sim}1^{\circ}C$에서 다소 억제되었다.

• Journal of Plant Biology
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• 제34권3호
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• pp.201-213
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• 1991

This study has been carried out to investigate the ultrastructural changes, formation of storage materials in endosperm cells with electron microscope during the seed formation of Panax ginseng C.A. Meyer. In the early stage of seed formation with green seed coat, the endosperm was cellular type. Cell plate was largely composed of dictyosome vesicles in early stage of wall formation after mitosis. Central vacuole was gradually subdivided into several small-sized vacuoles. During the differentiation of plastids, some proplastid was replaced by amyloplast with starch grains and lamellar structure. A number of mitochondria with well developed cristae were distributed in cytoplasm. Rough endoplasmc reticulum, dictyosome, microbody, free ribosomes and polysomes were evenly distributed in cytoplasm. Spherical spherosomes were formed from dictyosome containing the lipid materials of even electron density. Protein bodies were formed by interfusing between vacuoles and vesicles derived from rough endoplasmic reticulum which contained the amorphous protein of high electron density.

• 한국광학회:학술대회논문집
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• 한국광학회 2003년도 하계학술발표회
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• pp.36-37
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• 2003

To increase the high-density data storage, a new technique of Super-resolution near-field structure (Super-RENS) consisted of glass／SiN／Sb or AgOx／SiN has been proposed and investigated intensively as a promising structure for near-field ultrahigh-density optical storage. Hence it is important to determine the optical properties of AgOx by using ellipsometry. AgOx thin films were prepared by using magnetron sputtering technique while oxygen flow rate was varied, and the film growth of AgOx were monitored by using in situ ellipsometer. (omitted)

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.641-645
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• 2001

Storage drives for mobile devices, such as laptop computers or PDAs, are changing now. The data density of storage drives is becoming higher and sizes of those are becoming smaller and thinner. Spindle motors for rotating disk are also becoming smaller and thinner. But, large torque is required to reduce seek time. In this research, inner rotor type spindle motor suitable for thin thickness has been developed. Rotor and stator are optimized structurally for large torque performance with small size. Especially, high vibration and shock performances, which are essential to mobile devices, are analyzed in detail.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.105-111
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• 1996

The conditions of cold stroage of Citrus unshiu Marc. var. okitsu produced in Cheju were investigated. The changes of peel moisture contents soluble solids, total sugar, vitamin C and density were slightly occured, and decay ratio was below 20% on keeping freshness relatively till late of March during cold storage. After thats decayed citrus fruits were increased gradually mainly from cold injury with lower temperature and high humidity. The loss of fruit weight, decrease of fruit hardness, and decrease of acid content were occured gradually during cold stroage. Because of the difficulty of long term storage for Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits every year.

• 태양에너지
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• 제20권4호
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• pp.61-67
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• 2000

The purpose of this study is to improve heat transfer by attaching rectangular fins to tube. Experiments were carried out under the following conditions - Aspect ratio$(W_f/R_f)$ is 0.7, 1.2 and 1.8. Temperature conversion between high and low positions of water in the thermal storage appeared because maximum density point of water is about $4^{\circ}C$ and inlet direction of working fluid influenced conductive heat transfer Compared with the unfinned tube(bare tube), the rectangular tube increased the ice thermal storage energy and the ice thermal storage energy was increased as aspect ratio was increased.