• JSTS:Journal of Semiconductor Technology and Science
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• 제13권4호
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• pp.291-302
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• 2013

NAND flash memory (NFM) based storage devices, e.g. Solid State Drive (SSD), are rapidly replacing conventional storage devices, e.g. Hard Disk Drive (HDD). As NAND flash memory technology advances, its specification has evolved to support denser cells and larger pages and blocks. However, efforts to fully understand their impacts on design objectives such as performance, power, and cost for various applications are often neglected. Our research shows this recent trend can adversely affect the design objectives depending on the characteristics of applications. Past works mostly focused on improving the specific design objectives of NFM based systems via various architectural solutions when the specification of NFM is given. Several other works attempted to model and characterize NFM but did not access the system-level impacts of individual parameters. To the best of our knowledge, this paper is the first work that considers the specification of NFM as the design parameters of NAND flash storage devices (NFSDs) and analyzes the characteristics of various synthesized and real traces and their interaction with design parameters. Our research shows that optimizing design parameters depends heavily on the characteristics of applications. The main contribution of this research is to understand the effects of low-level specifications of NFM, e.g. cell type, page size, and block size, on system-level metrics such as performance, cost, and power consumption in various applications with different characteristics, e.g. request length, update ratios, read-and-modify ratios. Experimental results show that the optimized page and block size can achieve up to 15 times better performance than the conventional NFM configuration in various applications. The results can be used to optimize the system-level objectives of a system with specific applications, e.g. embedded systems with NFM chips, or predict the future direction of NFM.

• 한국경영과학회지
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• 제35권2호
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• pp.89-114
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• 2010

This study empirically investigated the effects of the target costing system as well as information technology(IT) infrastructure on the knowledge management processes(i.e., socialization, externalization, combination and internalization) and the performance of a firm. This study also examined an impact of the social capital(i.e., inter-departmental communication, trust, cooperation and integration) on the adoption and development of the target costing and the IT infrastructure. The results of this study showed that inter-departmental communication, trust and integration have a significant positive impact on the adoption of the target costing. It was also found that the effects of inter-departmental communication and integration on the development of storage and transfer infrastructure are significant and positive. However, in the adoption of search infrastructure, only the impact of inter-departmental integration was significant. The results of regression analyses presented that the target costing has significant influence on the four processes of knowledge management. It was also observed that the effects of storage and transfer infrastructure on combination are significant and positive. In search infrastructure, the impact on combination and internalization was significant. According to the results of this study, it was found that when the adoption level of the target costing is high, search infrastructure mainly affects the three processes(i.e., socialization, combination and internalization). However, under a low adoption level of the target costing, the impact of storage and transfer infrastructure on the whole processes was significant and positive. Thus, it is assumed that storage and transfer infrastructure complements a low level of the target costing adoption through the active transfer and sharing of explicit and tacit knowledge.

• 한국실내디자인학회논문집
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• 제25호
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• pp.253-261
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• 2000

Except the time when the relics of the museum are exhibited or loaned to the public, they are stored in a storage. Therefore, the environmental condition of a storage is a important factor. But in Korea, the appearance of the building and exhibition design are emphasized more than any other factors in planing museums, so the preservation technology has not yet reached the appropriate level and leaded to some environmental problem in the museum storage. The purpose of this study is to suggest guideline for an apt storage system by reconsidering practical notes in planning storage and give a efficient long-term plans examinable category. So this study based on the research had been stated from the recognition that the relics should be planned and placed differently in sorts, and developed this by researching the theory related to the matter throughout documents and to cope with the low efficiency in its essential role compared to the massive investment and through on-the-spot surveys emphasizing on the storage of the domestic museums in progress since 1995. Hereafter it compares the actual condition and problems of the domestic museum planning with the ones abroad, and analyzes the characteristic and difference between the two, and then establish an organized storage system.

• Industrial Engineering and Management Systems
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• 제11권4호
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• pp.331-338
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• 2012

This research proposes a Pareto-based multi-objective optimization approach to class-based storage warehouse design, considering a two-block warehouse that operates under the class-based storage policy in a low-level, picker-to-part and narrow aisle warehousing system. A mathematical model is formulated to determine the number of aisles, the length of aisle and the partial length of each pick aisle to allocate to each product class that minimizes the travel distance and maximizes the usable storage space. A solution approach based on multiple objective particle swarm optimization is proposed to find the Pareto front of the problems. Numerical examples are given to show how to apply the proposed algorithm. The results from the examples show that the proposed algorithm can provide design alternatives to conflicting warehouse design decisions.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.697-700
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• 2005

Aquifer Thermal Energy Storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop an ATES system which has certain hydrogeological characteristics, understanding of the thermo hydraulic processes of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermo hydraulic transfer for heat storage is simulated using FEFLOW according to two sets of pumping and waste water reinjection scenarios of heat pump operation in a two layered confined aquifer. In the first set of model, the movement of the thermal front and groundwater level are simulated by changing the locations of injection and pumping well in seasonal cycle. However, in the second set of model the simulation is performed in the state of fixing the locations of pumping and injection well. After 365 days simulation period, the temperature distribution is dominated by injected water temperature and the distance from injection well. The small temperature change is appears on the surface compared to other slices of depth because the first layer has very low porosity and the transfer of thermal energy are sensitive at the porosity of each layer. The groundwater levels and temperature changes in injection and pumping wells are monitored to validate the effectiveness of the used heat pump operation method and the thermal interference between wells is analyzed.

• 한국가스학회지
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• 제14권6호
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• pp.27-30
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• 2010

본 논문은 LNG 냉열에너지를 이용한 지역집단 냉방에너지 시스템을 공급하기 위한 시스템 공정설계에 관한 연구이다. 새로이 개발한 LNG 냉방시스템은 여러 개의 열교환기, LNG 저장탱크, 열매체 저장탱크, 여러 개의 냉열에너지 저장탱크, 가스냉방기, 압축기, 정압기, 저온 및 고온에너지 공급배관 등으로 구성되도록 설계하였다. 또한, 가스냉방기는 여름철에 도시가스 소모량에 의해 충분하지 못한 LNG 냉열에너지를 안정적으로 공급하기 위해 설치되었다. 냉방에너지 공급시스템은 공기라는 열매체와 200kcal/kg의 냉열에너지를 가진 LNG 사이의 열교환 작용에 의해 냉방에너지를 공급하는 효율성과 안전성을 함께 갖추고 있다. 또한, LNG 냉열에너지를 이용한 지역집단 냉방에너지 공급시스템은 공기중으로 CO2나 프레온 가스를 방출하기 않는다는 장점을 간고 있다.

• 전기학회논문지
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• 제64권1호
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• pp.196-200
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• 2015

The switching noise in the power electronics of the power conversion equipment (Power Conditioning System) for large energy storage devices are generated. Since the burst-level transient noise from being generated in the power system at a higher power change process influences the control circuit of the low voltage driver circuit. Noise may cause the malfunction of the control device even if no dielectric breakdown leads to a control circuit. To overcome this, this paper proposes the installation of an additional nano-surge protection device on the power supply DC output circuit of the battery management unit.

• 한국식품영양과학회지
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• 제30권5호
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• pp.858-864
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• 2001

젖산나트륨과 복합지방대체제가 저지방 볼로나의 품질과 냉장 중 저장안정성에 미치는 영향에 관하여 조사하였다. 유화형 볼로나를 대조구로 하여 일반성분을 분석한 결과 수분 600%, 지방 22% 및 단백질 함량이 12.4%를 함유하는, 반면 저지방 볼로나는 수분 73~76%, 지방 ~2% 및 단백질함량이 14~15%로 기존의 유화형 볼로나에 비하여 고단백, 저지방 소시지이었다. 저장 중 유화형 및 저지방(<3%) 볼로나의 유리수분량과 진공감량이 증가함에 따라 조직의 경도가 감소하였고(p<0.05), 총균수는 증가하였으나, 냉장 8주에 모두 가식 부위에 있었다. 젖산나트륨과 지방대체제를 첨가한 저지방 볼로나가 기존의 유화형 볼로나에 비해 가열 감량이 낮았으며(p<0.05) 경도를 비롯한 조직감은 높았다. 저지방 볼로나는 젖산나트륨의 첨가량이 증가할수록 유리수분량과 경도가 증가하였고, TBA값은 오히려 낮은 결과를 보여주었다. 냉장저장 중 젖산나트륨의 첨가에 따른 총균수에 영향이 나타났으며, 3.3% 젖산나트륨을 첨가한 처리구는 처리하지 않은 처리구보다 미생물의 성장억제 작용이 현저했다. 결론적으로 복합 지방대체제를 첨가한 저지방 볼로나의 젖산나트륨의 첨가량에 딸라 품질에 영향을 미쳤으며, 총균수와 TBA값을 낮출 수 있었다. 차후의 연구로 저지방 소시지에서 오염될 수 있는 Listeria monocytogenes 등과 같은 특정균을 일정균수($10^3$CFU/g) 접종함으로써 젖산나트륨의 특정미생물억제 효과에 관한 연구가 필요하다고 사료된다.

• 한국물환경학회지
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• 제23권4호
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• pp.490-497
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• 2007

A Combined sewer overflows (CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available (which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a continuous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban drainage system used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range $3{\times}DWF$ (dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a decision of storage volume for CSOs reduction and water quality protection.

• 한국물환경학회지
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• 제22권6호
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• pp.1068-1074
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• 2006

For receiving water quality protection a control systems of urban drainage for CSOs reduction is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as storm-water detention storage is highly dependant on the temporal variability of storage capacity available as well as the infiltration capacity of soil and recovery of depression storage. For the continuous long-term analysis of urban drainage system this study used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model has evolved that offers much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. Runoff characteristics manifested the unique characteristics of the subject area with the infiltration capacity of soil and recovery of depression storage and was examined appropriately by sensitivity analysis. This study presented the average annual CSOs, number of CSOs and event mean CSOs for the decision of storage volume.