• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.69-75
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• 2005

The storability of chicon was compared by packing it with PE box, wrap, LDPE (low density polyethylene) film that was 25 and 50um thickness, respectively and storing at 1 and $10^{\circ}C$ under light and dark conditions. The visual quality depending on dehydration was deteriorated at more than $2\%$ weight loss during storage. In packing treatments, chicon packed with PE box lost fresh weight to $3\%\;at\;10^{\circ}C\;and\;2\%\;at\;1^{\circ}C$, while non- penetrated film treatment, wrap, 25 and 50um thickness LDPE film, showed less than $1\%$ weight loss. The carbon dioxide concentration in package was $3\~4\%\;in\;50{\mu}m$ LDPE film at $1^{\circ}C\; and\;25um$ LDPE film at $10^{\circ}C$. The ethylene concentration in 50um LDPE film at $1^{\circ}C\;and\;25{\mu}m$ LDPE film at $10^{\circ}C$ was approximately 0.3 ppm and 0.5 ppm, respectively. Chiton stored in dark condition didn't turn to green, but it fumed green only in 3 days at $10^{\circ}C$ and in 6 days at $1^{\circ}C$ under light condition. The greening of chicon was less, the packing materials was thicker. The chlorophyll content represented the degree of greening showed less at $1^{\circ}C$ then at $10^{\circ}C$. The coefficient of correlation(r) between chlorophyll content and carbon dioxide concentration in package was 0.926 at $1^{\circ}C$ and 0.997 at $10^{\circ}C$. The visual quality except greening of packed chicon was maintained at $1^{\circ}C$ better than $10^{\circ}C$, and it was shown highest grade packed with $50{\mu}m$ LDPE film at $1^{\circ}C$ and packed with 25um LDPE film at $10^{\circ}C$. The vitamin C content in packed chicon was kept higher at $1^{\circ}C$ on storage temperatures, and 25um and 50um LDPE film on packing materials. According to these results, it can be proper condition for storage and marketing of chicon that 50um LDPE film at $1^{\circ}C$ and 25um LDPE film at $10^{\circ}C$. And dark condition is necessary to store chicon because it should turn green under tiny light condition.

• Korean Journal of Optics and Photonics
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• v.20 no.4
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• pp.230-235
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• 2009

Photopolymer is evaluated as better material than the others used for hologram storage, due to many advantages, such as high diffraction efficiency, easy processing, and self-developing. In this study, chalcogenide inorganic compound ($SeO_2$) which has optical activity, was added to polyvinyl alcohol/acrylamide photopolymer films. In order to optimize diffraction efficiency of these photopolymer films, we prepared the photopolymer films with various film thicknesses and Eosin Y content. Diffraction efficiency of the photopolymer films were measured using a 532 nm laser at $40^{\circ}$ incident angle. As a result, the phtopolymer film with Eosin Y content of 0.0045 g and thickness of $297{\mu}m$ showed the highest diffraction efficiency (78.70%).

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.451-452
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• 2016

최근 풍력 및 태양광 발전과 같은 분산전원 시스템의 설비가 증가함에 따라 전력 생산자가 늘어나고 있으며 발전량이 불규칙적인 신재생에너지 자원을 전력 수요에 따라 효율적으로 운용하고 관리하기 위한 에너지 저장장치(Energy storage system : ESS)의 필요성이 증가하고 있다. 최근에는 기존의 중앙집중 방식의 전력 시스템이 가지는 여러 문제를 해결하기 위해 여러 분산 발전 요소들과 에너지 저장장치, 부하 및 계통을 상호 연결한 마이크로그리드의 개념이 제안되고 있다. 마이크로그리드 내에서 분산전원과 계통에 ESS가 연계 되면 전력수급 상황에 따라 잉여전력이 발생할 때 전력을 저장할 수 있으며 전력수요가 클 때 저장된 전력을 부하에 공급하여 전력설비를 보다 안정적이고 효율적으로 운용할 수 있다. 본 논문에서는 풍력발전 시스템, 양방향 충/방전이 가능한 ESS, 부하 및 계통이 연계된 마이크로그리드를 대상으로 이를 효율적으로 운용하고 계통전력 사용을 최소화 할 수 있는 독립형 마이크로그리드의 자율적 제어기법에 대한 연구를 수행한다. 전력수급 상황에 따라 각 요소들의 운전 모드를 결정하는 기법이 제시되고 각 동작 모드에서의 분석 및 시뮬레이션에 의한 검증을 통하여 본 제어기법의 효용성을 입증한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.7
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• pp.1-5
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• 2012

At the present time when the limits of the magnetic storage systems appear, the holographic data storage (HDS) devices with high data transfer rate and high recording density are emerging as attractive candidates for next-generation optical storage devices. In this paper, to effectively improve the detection performance that is degraded by the two-dimensional inter-symbol interference under the HDS channel environment and the pixel misalignment, an iterative two-dimensional equalization scheme is proposed based on the contraction mapping theorem. In order to evaluate the performance of the proposed scheme, for various holographic channel environments we measure the BER performance using computer simulation and compare the proposed one with the conventional threshold detection scheme, which verifies the superiority of the proposed scheme.

• The Transactions of the Korea Information Processing Society
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• v.2 no.5
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• pp.787-796
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• 1995

In this paper, a mechanism to enhance the utilization of the tertiary storage devices such as optical disk, digital tape and so on is proposed. For this purpose, we suggest a storage structure with a CD-ROM and multiple disk and design an efficient mechanism to represent the continuous media stored in CD-ROM. The continuous media storage structure proposed in this pater can enhanced the retrieval capability of information by sending data using a shared bus with high bandwidth. And a continuous media representation mechanism not only can reduce the discontinuity of representation using parallel operation of fetch and representation but also minimize the variance of service time and the missing ratio of re-reference requirement by residing frequently accessed object on the disk.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.22-29
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• 2011

The experiment investigated effect of duration, temperature, and light condition during chilling treatment on growth and flowering of four Campanula species in a factorial experiment. Two parent species, Campanula punctata Lam. var. rubriflora Mak. and C. Punctata Lam., and their two $F_1$ hybrids, C. punctata Lam. ${\times}$ C. punctata Lam. var. rubriflora Mak. ('Jiknyeo') and C. punctata Lam. var. rubriflora Mak. ${\times}$ C. punctata Lam. ('Gyeonu'), were used. Plants were cultured in vitro for five weeks at $25^{\circ}C$ under about $75{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD before being chilled at 4 or $25^{\circ}C$ for 3, 6, or 9 weeks under a darkened or lighted (about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) condition. After chilling treatment, plants were transplanted to 10 cm pots filled with a commercial growing medium and were transferred to environment-controlled growth chambers and subsequently to a greenhouse to observe their reproductive growth. Growth of all species and flowering of a $F_1$ hybrid 'Jiknyeo' were affected by duration, temperature, and light condition during chilling treatment. The greatest growth and survival percentage were observed in C. punctata Lam. var. rubriflora Mak. The survival percentage was greater when plants were chilled in a lighted than darkened condition, whereas it decreased when plants were chilled more than six weeks in vitro. Among the four species tested, flowering was observed only in a $F_1$ hybrid 'Jiknyeo' with 62.5% flowering plants when it was chilled at $25^{\circ}C$ for three weeks under a lighted condition. Percent flowering plant was affected by duration, temperature, and light condition during chilling treatment. Three-week chilling at $4^{\circ}C$ under a darkened condition significantly reduced days to flowering. These results suggest that the low temperature requirement for flowering is not qualitative but quantitative in Campanula species. Further experiment with more number of plants is necessary to ascertain this conclusion.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.82-87
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• 2001

A study was performed to establish detection methods by viscometric and pulsed photostimulated luminescence (PPSL) methods for irradiated com powder. Viscosity was determined using a Brookfield DV-rotation viscometer at 3$0^{\circ}C$ and operated at 30, 60, 90, 120, 150, 180, and 210 rpm. All irradiated samples showed a decrease in Viscosity with increasing stirring speeds (rpm) and irradiation doses. Treatments at 1~3 kGy significantly decreased the viscosity. The photon counts of irradiated corn powder were measured by PPSL immediately after irradiation and exhibited an increase with increasing irradiation dose. The photon counts of irradiated com powder almost disappeared with lapse of time in room conditions, but detection of irradiation was still possible after one month at darkroom conditions. Consequently, these results suggest that the detection of irradiated com powder is possible by both viscometric and PPSL methods.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.6
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• pp.318-330
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• 2002

This paper discusses the design and implementation of a video server which uses tertiary device, such as magneto-optical jukebox or tape library, as a source of media archiving. In order to handle the tertiary device in the framework of disk-based stream service model, a sophisticated streaming model is required for server and it should consider the device-specific performance characteristics of tertiary storage. We have carefully designed the streaming mechanism for server whose key functionalities include stream scheduling, disk caching and admission control. The proposed system has been implemented on Windows 2000 platform which is equipped with a magneto-optical jukebox. The design principles of the server are validated with the experiments and the performance characteristics is analyzed.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.250-254
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• 1994

The quality characteristics of freeze-dried Chungkook-jang soup, stored at $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$ was investigated. Peroxide value(POV) was increased as the storage time was extended. Browning reaction occured earlier in the sample stored at $45^{\circ}C$ than those stored at $35^{\circ}C$ and $25^{\circ}C$. Red color developed more intensely in the sample stored at $45^{\circ}C$. However, moisture content was not changed during storage. Regression analyses between sensory scores and quality characteristics showed that the peroxide formation of oil contained in Chungkook-jang soup was the major quality index for the deterioration of Chungkoak-jang soup.

• Journal of Energy Engineering
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• v.26 no.4
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• pp.107-117
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• 2017

Since South Korea started to apply Renewable Portfolio Standard (RPS) in 2012, there have been huge investment for deploying renewable technologies. Recently, the government determined to incentivize battery energy storage system(BESS) with renewable generations in order to induce the improvement of dispatching capability. In this paper, the annual pattern of PV generation based on actual generation data in South Korea is analyzed and the duration curve of capacity factor is proposed in order to provide the simplified analyzing methodology of present support policy for additional BESS installation for decision maker who is responsible for supply and demand planning. With suggested methodology, the range of appropriate BESS size with respect to the variation of system marginal price(SMP) and renewable energy certificate(REC) price can be derived briefly, and decision makers easily evaluate the effect of support scheme. Current policy for BESS installation support present additional BESS-related installation policy may give incentives to developers partially, however, the dependence between BESS size and benefit components (SMP and REC) can limit the deployment of the various portfolios of the BESS. Therefore, when improving the current policy in future, addressing the dependence between the technical aspects of battery size and the benefit components separately by the technical and economical parts is needed to set the suitable compensation rules for the renewable generation and BESS.