• Journal of Ecology and Environment
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• 제37권2호
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• pp.69-79
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• 2014

Soil organic carbon (SOC) in the Arctic is vulnerable to climate change. However, research on SOC stored in the high Arctic regions is currently very limited. Thus, this study was aimed at understanding the distribution and characteristics of SOC with respect to geomorphology and vegetation in Svalbard. In August 2011, soil samples were collected near the Vestre Lov$\acute{e}$nbreen moraine. Sampling sites were chosen according to altitude (High, Mid, and Low) and differences in levels of vegetation establishment. Vegetation coverage, aboveground biomass, and SOC contents were measured, and density-size fractionation of SOC was conducted. The SOC content was the highest in the Mid site ($126.9mg\;g^{-1}$) and the lowest in the High site ($32.1mg\;g^{-1}$), although aboveground biomass and vegetation coverage were not different between these two sites. The low SOC content measured at the High site could be related to a slower soil development following glacial retreat. On the other hand, the Low site contained a high amount of SOC despite having low vegetative cover and a high ratio of sand particles. These incompatible relationships between SOC and vegetation in the Low site might be associated with past site disturbances such as runoff from snow/glacier melting. This study showed that geomorphological features combined with glacier retreat or melting snow/glacier effects could have affected the SOC distribution and vegetation establishment in the high Arctic.

• 한국콘텐츠학회논문지
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• 제5권1호
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• pp.229-236
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• 2005

System-On-a-Chip(SOC)을 테스트하는 동안에 요구되는 테스트 시간과 전력소모는 SOC내의 IP 코어의 개수가 증가함에 따라서 매우 중요하게 되었다. 본 논문에서는 수정된 스캔 래치 재배열을 사용하여 scan-in 전력소모와 테스트 데이터의 양을 줄일 수 있는 새로운 알고리즘을 제안한다. 스캔 벡터 내의 해밍거리를 최소화하도록 스캔 래치 재배열을 적용하였으며 스캔 래치 재배열을 하는 동안에 스캔 벡터 내에 존재하는 don't care 입력을 할당하여 저전력 및 테스트 데이터 압축을 하였으며 ISCAS 89 벤치마크 외호에 적용하여 모든 경우에 있어서 테스트 데이터를 압축하고 저전력 스캔 테스팅을 구현하였다.

• Journal of Electrochemical Science and Technology
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• 제13권4호
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• pp.472-478
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• 2022

Solar energy harvesting is practiced by various nations for the purpose of energy security and environment preservation in order to reduce overdependence on oil. Converting solar energy into electrical energy through Photovoltaic (PV) module can take place either in on-grid or off-grid applications. In recent time Lithium battery is exhibiting its presence in on-grid applications but its role in off-grid application is rarely discussed in the literature. The preliminary capacity and Peukert's study indicated that the battery quality is good and can be subjected for life cycle test. The capacity of the battery was 10.82 Ah at 1 A discharge current and the slope of 1.0117 in the Peukert's study indicated the reaction is very fast and independent on rate of discharge. In this study Lithium Iron Phosphate battery (LFP) after initial characterization was subjected to life cycle test which is specific to solar off-grid application as defined in IEC standard. The battery has delivered just 6 endurance units at room temperature before its capacity reached 75% of rated value. The low life of LFP battery in off-grid application is discussed based on State of Charge (SOC) operating window. The battery was operated both in high and low SOC's in off-grid application and both are detrimental to life of lithium battery. High SOC operation resulted in cell-to-cell variation and low SOC operation resulted in lithium plating on negative electrode. It is suggested that to make it more suitable for off-grid applications the battery by default has to be overdesigned by nearly 40% of its rated capacity.

• Journal of Power Electronics
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• 제18권1호
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• pp.129-136
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• 2018

An accurate state-of-charge (SOC) estimation ensures the reliable and efficient operation of a lithium-ion battery management system. On the basis of a combined electrochemical model, this study adopts the forgetting factor least squares algorithm to identify battery parameters and eliminate the influence of test conditions. Then, it implements online SOC estimation with high accuracy and low run time by utilizing the low computational complexity of the unscented Kalman filter (UKF) and the rapid convergence of a particle filter (PF). The PF algorithm is adopted to decrease convergence time when the initial error is large; otherwise, the UKF algorithm is used to approximate the actual SOC with low computational complexity. The effect of the number of sampling particles in the PF is also evaluated. Finally, experimental results are used to verify the superiority of the combined method over other individual algorithms.

• 한국산학기술학회논문지
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• 제21권3호
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• pp.585-593
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• 2020

현재까지 총 29건의 전기저장장치의 화재가 발생되었는데, 이 중 22건이 신재생에너지 연계용이며, 완전충전 이후, 운전대기 상태인 휴지기간 동안에 계절과 무관하게 화재사고가 발생되었다. 이것은 병렬로 연결된 셀들의 SOC 상태가 서로 다른 경우, 의도하지 않게 SOC가 높은 셀에서 낮은 셀로 전류가 이동하는 셀프에너지 밸런싱 현상으로, 일부 셀이 과충전되어 열폭주로 인한 화재의 원인으로 평가되고 있다. 따라서, 본 논문에서는 전기저장장치의 셀프에너지 밸런싱을 방지하는 새로운 BMS의 회로구성과 운용 알고리즘 그리고 SOC 평가알고리즘을 제안한다. 제안한 알고리즘과 구현한 BMS를 바탕으로 리튬이온전지의 열화 특성과 열화 및 정상 셀 간의 셀프에너지 밸런싱 특성을 분석한 결과, 정상 셀 대비 열화 셀의 방전 용량 비율은 91.75[%]이며, 열화율이 8.25[%]임을 알 수 있었고, SOC가 높은 정상 셀에서 SOC 낮은 열화 셀로 전류가 이동하는 셀프에너지 밸런싱 현상이 발생함을 확인하였다. 또한, 셀프에너지 밸런싱 전류가 과도하게 높아지는 경우, BMS가 확실하게 셀들의 병렬연결을 분리하여, 리튬이온전지의 안전성을 향상시킬 수 있어, 본 논문에서 제안한 BMS의 유용성을 확인하였다.

• Journal of Power Electronics
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• 제16권1호
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• pp.27-37
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• 2016

In this paper, a mixed algorithm is proposed to overcome the limitations of the conventional algorithms, which cannot be applied in various driving patterns of drivers. The proposed algorithm based on the coulomb counting method is mixed with reset algorithms that consist of the enhanced OCV reset method and the DCIR iterative calculation method. It has many advantages, such as a simple model structure, low computational overload in various profiles, and a low accumulated SOC error through the frequent SOC reset. In addition, the enhanced parameter based on a mathematical analysis of the second-order RC ladder model is calculated and is then applied to all of the methods. The proposed algorithm is verified by experimental results based on a 27-Ah LiPB. It is observed that the SOC RMSE of the proposed algorithm decreases by about 9.16% compared to the coulomb counting method.

• 여성건강간호학회지
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• 제7권3호
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• pp.348-358
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• 2001

This study was designed to identify the relationship between the level of sense of coherence(SOC) and coping resources of nurses working in hospital. The subjects of this study were 248 nurses working at C University hospital in Seoul. The data was collected during the period from July 1. to July 14. 2001. The insruments for this study were SOC scale by Antonovsky(1987) and Coping Resources Inventory by author. The analysis of data was done by simple statistics, ANOVA and Pearson correlation coefficient with SAS program. The results of this study were as follows: 1. Total mean SOC was 132.1/203.0 with a range 96.0 to 171.0. The mean score of this item was arranged according to three areas. The meaningfulness was 4.9, managability was 4.7, and comprehensibility was 4.2. 2. Total mean coping resources was 144.5/225.0 with a range 93.0 to 190.0. The highest mean score of item according to the area was social support 4.0 and the lowest mean score was self care coping 2.7. 3. A significant statistical difference between age, religion, spending money and SOC was found. 4. Significant statistical difference between age, educational level, spending money, working period and coping resources were found. 5. Coping resources by the level of SOC was high in the highest group of SOC(F=6.19, p=0.00). With respect to the area of coping resources, higher group of SOC was using much coping resources generally except area of leisure. 6. SOC was positively related to age(r=0.17), working periods(r=0.16), each SOC area, coping resources and all area of them except leisure. 7. The coping resources were positively related to age(r=0.21), working periods(r=0.21), SOC (r=0.49), each coping resources area, and each SOC area. In conclusion, we confirmed that the level of SOC of the subjects was low relatively and the high level of sense of coherence was related to the high score of coping resources. Therefore, it could also contribute to select suitable nurses in their fields. In the future, it's necessary to develop strategies improving SOC.

• 한국조경학회지
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• 제47권5호
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• pp.28-40
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• 2019

지역 및 인구집단의 사회경제적 지위에 따른 생활 SOC 공급의 불균형 문제를 해결하기 위해 포용도시 정책에 대한 논의가 확장하고 있다. 본 연구의 목적은 포용적 도시공원 정책 추진을 위한 대안적 지표로 공원결핍지수(Index of Park Derivation, IPD)를 제안하고, 이를 7대 광역시에 적용해 공원 정책 필요도가 상대적으로 높은 지역을 선정하는 것이다. 주요 연구결과는 다음과 같다. 첫째, 포용도시와 공원기능에 대한 관련 이론 및 선행연구 검토를 통해 포용적 도시공원 정책 개념을 "노인, 어린이, 저소득층, 폭염 미세먼지 등의 환경 재난 재해 취약계층 등 사회경제 및 환경적 지위가 낮은 지역 및 인구집단을 우선적으로 고려해 양질의 공원서비스를 공급 관리하는 정책"이라고 조작적으로 정의했다. 둘째, 공원서비스 수준, 인구구조 특성, 경제 및 교육 수준, 건강 수준, 환경적 취약성 등 5개 부문의 17개 변수를 종합하여 공원결핍지수(Index of Park Derivation, IPD)를 개발했다. 공원결핍지수를 구성하는 변수들은 체육시설, 어린이집, 유치원, 공공도서관 등 공원 외의 생활 SOC 정책에도 적용 가능할 것으로 판단된다. 셋째, 7대 광역시 1,148개 읍면동 지역에 공원결핍지수를 적용한 결과 광역시별 공원서비스 필요도가 상대적으로 높은 지역들이 도출되었다. 서울특별시 강북구 삼각산동, 부산광역시 강서구 대저1동, 대구광역시 동구 안심1동, 인천광역시 부평구 삼산1동, 광주광역시 광산구 신창동, 대전광역시 대덕구 회덕동, 울산광역시 북구 농소3동이 지역별 공원 정책필요도 1순위로 도출되었다. 본 연구는 정부 및 지자체가 쉽게 접근 활용할 수 있는 통계 및 지리정보 데이터에 기반해 포용적 도시 공원 정책을 추진할 수 있는 대안적 지표를 제안했다는 의의를 갖는다.

• 간호행정학회지
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• 제17권4호
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• pp.493-507
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• 2011

Purpose: The aim of this study was to investigate the effect of sense of coherence (SOC) on occupational stress, psychosocial stress and quality of life (QOL) of nurses working in a hospital. Methods: The participants were 401 nurses working in S hospital in Seoul. A stratified random sampling was performed for the all nurses in S hospital which were grouped by age and work unit. Data were collected by a self-report survey. Data analyses included descriptive statistics, t-test, Pearson correlations, multiple linear regressions, and ANOVA. Results: This study showed nurses' occupational stress was at high risk and their psychosocial stress, at low risk. It also showed that those two types of stress are mutual predictors for each other and that SOC was a predictor for both types of stress. For QOL, SOC was also a predictor in SF-36 and MCS (Mental Component Summary). Therefore, SOC may be considered as a major controlling factor for stress and QOL. Conclusion: The results indicate the need to develop programs that enhances nurses' SOC, programs that could be utilized as an intervention to reduce nurses' stress and to promote nurses' QOL.

• 대한전자공학회논문지SD
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• 제41권12호
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• pp.83-90
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• 2004

본 논문은 SOC의 테스트 데이터 압축과 전력소비를 단축시키기 위한 효율적인 스캔 테스트 방법을 제안한다. 제안된 테스트 방법은 deterministic 테스트 데이터와 그 출력응답을 분석하여 출력응답의 일부분이 차기에 입력될 테스트 데이터로 재사용될 수 있는지를 결정한다. 실험결과, 비압축된 deterministic 입력 테스트 데이터와 그 응답간에 높은 유사도가 있음을 알 수 있다. 제안된 테스트 방법은 ISCAS'89 벤치마크 회로를 대상으로 소요되는 클럭 시간을 기준으로 평균 29.4%의 전력소비단축과 69.7%의 테스트 데이터 압축을 가져온다.