• Journal of Ecology and Environment
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• v.37 no.2
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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.

• The Journal of the Korea Contents Association
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• v.5 no.1
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• pp.229-236
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• 2005

Testing time and power consumption during testing System-On-a-Chip (SOC) are becoming increasingly important as the IP core increases in a SOC. We present a new algorithm to reduce the scan-in power and test data volume using the modified scan latch reordering. We apply scan latch reordering technique for minimizing the hamming distance in scan vectors. Also, during scan latch reordering, the don't care inputs in scan vectors are assigned for low power and high compression. Experimental results for ISCAS 89 benchmark circuits show that reduced test data and low power scan testing can be achieved in all cases.

• Journal of Electrochemical Science and Technology
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• v.13 no.4
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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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• v.18 no.1
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.585-593
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• 2020

Until now, 29 fire accidents have occurred; 22 of them were caused by the interconnection of renewable energy sources that occurred during the rest period after the lithium-ion battery had been fully charged regardless of the seasons. The fire accidents of ESS were attributed to thermal runaway due to the overcharging of a few cells with the phenomenon of self-energy balancing, which is unintentional current flow from cells with a high SOC to the low cells if the SOC condition of each cell connected in parallel is different. Therefore, this paper proposes a novel configuration and operation algorithm of the BMS to prevent the self-energy balancing of ESS and presents a hybrid SOC estimation algorithm. From the test results of the self-energy balancing phenomenon between aging and normal cells based on the proposed algorithm and BMS, it was confirmed the possibility of self-energy balancing, which is unintentional current flow from cells with a high SOC to cells with a low SOC. In addition, the proposed configuration of the BMS is useful and practical to improve the safety of lithium-ion batteries because the BMS can reliably disconnect a parallel connection of the cells if the self-energy balancing current becomes excessively high.

• Journal of Power Electronics
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• v.16 no.1
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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.

• Women's Health Nursing
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• v.7 no.3
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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.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.5
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• pp.28-40
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• 2019

In order to resolve the imbalances in the supply of living SOCs according to socio-economic status, location, and population groups, the discussions on inclusive city policies are expanding. The purpose of this study is to propose an Index of Park Derivation (IPD) as an alternative indicator for the promotion of an inclusive urban park policy that can be applied in the 7 major metropolitan cities to select a region with a relatively high park needs. The main research results are as follows. First, the concept of an inclusive urban park policy is defined as "a policy to supply to manage high-quality park services with priority given to areas with low socio-economic and environmental status, such as a large amount of elderly, children, low-income families, areas vulnerable to disasters, such as heat and fine dust, and population groups." Second, we developed the index of park derivation (IPD), which is a combination of 17 variables including park service level, demographic characteristics, economic and educational level, health level, and environmental vulnerability. The variables that constitute the index of park deprivation (IPD) can be applied to SOC policies outside the parks, such as sports facilities, daycare centers, kindergartens, and public libraries. Third, applying index of park deprivation (IPD) to 1,148 Eup/Myeon/dong areas of the 7 metropolitan cities resulted in areas with relatively high park service needs. This study implies that the central and the local government suggest an alternative index to promote an inclusive urban park policy based on statistical and geographical information and data that can be easily accessed and utilized.

• Journal of Korean Academy of Nursing Administration
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• v.17 no.4
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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.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.12
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• pp.83-90
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• 2004

This paper proposes an efficient scan testing method for compression of test input data and reduction of test power for SOC. The proposed method determines whether some parts of a test response can be reused as a part of next input test data on the analysis of deterministic test data and its response. Our experimental results show that benchmark circuits have a high similarity between un-compacted deterministic input test data and its response. The proposed testing method achieves the average of 29.4% reduction of power dissipation based on the number of test clock and 69.7% reduction of test data for ISCAS'89 benchmark circuits.