• 전기학회논문지
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• 제65권8호
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• pp.1347-1354
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• 2016

This paper presents optimal operational scheduling model and economic assessment of Li-ion battery energy storage systems installed in non-residential customers. The operation schedule of a BESS is determined to minimize electric bill, which is composed of demand and energy charges. Dynamic programming is introduced to solve the nonlinear optimization problem. Based on the optimal operation schedule result, the economics of a BESS are evaluated in the investor and the social perspective respectively. Calculated benefits in the investor or customer perspective are the savings of demand charge, energy charge, and related taxes. The social benefits include fuel cost savings of generating units, construction deferral effects of the generation capacity and T&D infra, and incremental CO2 emission cost impacts, etc. Case studies are applied to an large industrial customer that shows similarly repeated load patterns according to days of the week.

• 천문학회보
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• 제44권2호
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• pp.60.4-60.4
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• 2019

Small bodies in the solar system are pristine leftovers of planetesimals since the formation epoch (~4.6 Gyr ago). After the formation, icy planetesimals have been preserved in the distant cold place beyond 30 au (i.e., Trans-Neptunian region) until recently without any catastrophic processes but have just been injected into inner region (<~5 au from the Sun) to be observed as comets. On the contrary, asteroids are rocky primitive objects (although some of them contains icy volatiles) distributing in the mainbelt between Mars and Jupiter orbits. Because of frequent encounters in the mainbelt, asteroids have experienced a number of repeated impacts until the present day. Namely, it is important to investigate thermal alternation process of cometary volatiles and refractories in the solar radiation field, whereas collisional and subsequence phenomena of asteroidal bodies. Although recent spacecraft observations revealed the physical natures on the surfaces of comets and asteroids, their interiors still remain largely unexplored. It is likely that a sudden brightening of a comet is associated with rapid sublimation of internal CO and CO2 or phase transition of amorphous H2O. An episodic dust ejection from an asteroid is causally related to an impact among asteroids, sudden sublimation of remaining subsurficial volatiles, etc. Because these transient phenomena provide rare opportunities to investigate their interiors, immediate observations using any optical instruments are particular important. In my presentation, I will review some examples of such transient phenomena in the solar system and propose possible collaborative research using the Korean Small Telescope Network.

• 생명과학회지
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• 제31권4호
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• pp.442-451
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• 2021

미세 플라스틱은 입자의 크기가 5 mm 이하인 플라스틱 조각을 말하며 미세 플라스틱의 오염은 해양 생태계와 인간의 건강과 관련되어 전 세계적인 관심사이다. 광범위하게 오염되어 있는 관계로, 미세 플라스틱은 물고기, 담치, 굴, 조개, 가리비와 같이 다양한 동물에 섭취되어 체내에 축적된다. 게다가, 섭취된 미세 플라스틱은 소장, 간, 신장 그리고 심지어 뇌에서도 높은 농도로 관찰된다. 해산물은 인간에게 있어 주요 단백질 공급원 중 하나이므로, 해산물의 소비는 인간이 미세 플라스틱에 노출되는 경로가 될 수 있다. 많은 근거들은 설치류에서 미세 플라스틱의 반복적인 경구 투여가 생식, 심장, 소화기, 내분비 그리고 심지어 신경계에서 병리적, 기능적 변화를 유도함을 가리킨다. 더욱이, 임신기와 수유기 동안 모체가 미세 플라스틱에 노출되면 새끼에서 대사의 항상성에 변화가 일어난다. 해산물은 세계적으로 3억 1천만 명 이상의 사람들에게 20% 이상의 단백질 공급원이라는 사실을 고려할 때, 미세 플라스틱은 인간의 몸에 축적되어 생리적 기능에 장애를 유발할 수 있다고 가정하는 것이 타당하다. 본 리뷰에서 우리는 해양에서 미세 플라스틱 오염의 현재 실태와 해양 동물 및 설치류에서 미세 플라스틱의 축적과 독성, 그리고 인간에게의 노출과 인간 건강에 미치는 잠재적인 영향에 대해 요약하였다.

• Asia pacific journal of information systems
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• 제10권2호
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• pp.71-95
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• 2000

Despite repeated exhortation about the importance of social and human dimensions of systems development, socio-organizational issues continue to be neglected and ignored in the current information systems practice. A review of the human information processing literature suggests that the reasons for this continuing lack of attention to social issues may be found in the limitations of human cognition and information processing capacities. Bostrom and Heinen(1978) and Kumar and Bjorn-Anderson(1990) also suggest that the inadequate attention to social problems and issues by the analyst could originate from the analysts limited problem perception. This research explores how the representation forms of information systems(IS) methodology used in understanding and modeling the problem situation affect such systems development problem perception. Typically, a system development methodology prescribes the use of system models(i.e., system representations) to understand, analyze, evaluate, and design the information system. Given the size and complexity of information systems, and the abstraction and simplification underlying the modeling process, system representations usually depict only a limited set of aspects of the system. Thus, a methodology whose representations are limited to technical aspects will tend to limit the analyst's perspective to a technical one only(Kumar & Welke, 1990). Following the same line of argument, in contrast, it is the conjecture of this study that a methodology which specifies both social and technical aspects of IS development will help the analyst develop a more comprehensive view of the IS problem domain. Based on the above concept, a theoretical model was first developed which explained the systems analysts cognitive process. Drawing on this model, a research model was developed hypothesizing the impacts of representation forms on problem identification. The model was tested using a laboratory experiment with 70 individual subjects. A special computer software was developed with a hypermedia authoring tool to conduct the experiments in order to avoid experimenter biases and to maintain consistency in administrating repeated experiments. The program, designed to replace the experimenter, consisted of functions such as presenting the subjects with problem material, asking the subjects questions, and saving the typed answers of the subjects. The results indicate that representation forms strongly influence problem identification. It was found that the use of the socio-technical representation form led to the findings of more social problems than the use of technical representation form. The results imply significant effects of representation forms on problem findings and also suggest that the use of adequate representation forms may help overcome dysfunctional effects of our limited information processing capacity.

• 대한간호학회지
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• 제45권2호
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• pp.221-230
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• 2015

Purpose: This study was done to examine how laughter therapy impacts serotonin levels, QOL and depression in middle-aged women and to perform a path analysis for verification of the effects. Methods: A quasi-experimental study employing a nonequivalent control group and pre-post design was conducted. Participants were 64 middle-aged women (control=14 and experimental=50 in 3 groups according to level of depression). The intervention was conducted five times a week for a period of 2 weeks and the data analysis was conducted using repeated measures ANOVA, ANCOVA and LISREL. Results: Results showed that pre serotonin and QOL in women with severe depression were the lowest. Serotonin in the experimental groups increased after the 10th intervention (p=.006) and the rise was the highest in the group with severe depression (p=.001). Depression in all groups decreased after the 5th intervention (p=.022) and the biggest decline was observed in group with severe depression (p=.007). QOL of the moderate and severe groups increased after the 10th intervention (p=.049), and the increase rate was highest in group with severe depression (p<.006). Path analysis revealed that laughter therapy did not directly affect depression, but its effect was indirectly meditated through serotonin variation (p<.001). Conclusion: Results indicate that serotonin activation through laughter therapy can help middle-aged women by lessening depression and providing important grounds for depression control.

• KIEAE Journal
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• 제12권4호
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• pp.13-19
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• 2012

The Earth's surface temperature still continues to rise, and extreme weather phenomena such as heat waves, drought, and precipitation have been repeated every year. It is reported that international communities attribute the main cause of the Earth's surface temperature rise to the excessive use of the fossil energy. Recently, the damage caused by climate change is getting worse, and the place where we live is suffering the most. Cities have been continuously growing not only meeting the basic functions of human habitation, work and leisure but also being places for various economic and social activities. But Cities, the victims of climate change, have grown only considering human needs and convenience rather than predicting their physical and ecological systems(Albedo effects, urban microclimate, resources and energy of the circulatory system, etc). In other words, the cities offer the cause of the problems of climate change, and even worsen the extreme weather phenomena without coping with them. Therefore, it is urgent priorities to protect the climate, to prevent the causes of the extreme weather phenomena and to enhance the adaptive capacity for the worse weather events. This study is to derive the concept for adapting to these climate changes which can make cities escape from exposure to these climate change impacts and make themselves safer places to live. And it analyzes some European cities and present developing models to implement planning methods. In this study, the concept of the climate adaptive cities will be suggested to prepare the adaptation measures for urban planners, and climate change adaptation models will be presented by analyzing some preliminary cases.

• 디지털융복합연구
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• 제18권6호
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• pp.187-196
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• 2020

IT 프로젝트 성과를 위한 두 가지(위험 기반, 지식 기반) 주요 관점을 통합적으로 연구하고자 하였으며, 민간부문보다 상대적으로 제약이 많은 공공부문 IT프로젝트가 성과를 확대하기 위해 관리할 요인으로 사용자 지식을 제안하고자 하였다. 이에 본 연구는 성과에 미치는 2가지 유형의 위험(사용자 관련 위험과 프로젝트 관리 위험) 요인을 실증분석하였으며, 사용자 지식을 조절효과로 검증하였다. 공공기관 IT 프로젝트 참여 경험이 있는 응답자를 대상으로, 132부의 데이터를 수집하여 Smart PLS 3.0으로 분석하였다. 연구결과, 낮은 사용자 관련 위험과 낮은 프로젝트 관리 위험은 IT 프로젝트 성과에 정(+)의 영향을 미치는 것으로 나타났다. 또한, 사용자 지식은 사용자 관련 위험과 낮은 프로젝트 관리 위험이 IT 프로젝트 성과에 미치는 영향을 강화하는 것으로 나타났다. 이러한 연구결과는 통합적 연구결과의 반복적인 검증이자, 공공부문 IT 프로젝트에서 갖는 사용자 지식의 중요성을 강조한다.

• 한국융합학회논문지
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• 제11권4호
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• pp.255-264
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• 2020

이 연구는 성과정보의 특성에 따른 의사결정자의 성과정보 활용 방식이 자원 배분과 관련한 의사결정에 미치는 영향을 실증적으로 분석하는 것이다. 이 연구는 이론적 논의를 토대로 일반행정, 경제정책, 환경정책의 3개 분야에 대한 성과시나리오를 설계하고, 각 시나리오에 대해 연구집단과 대조집단을 구분하였다. 연구집단은 측정지표를 활용한 성과정보를 제공하고, 대조집단에게는 달성여부에 대한 정보만을 제공하여 자원배분 의사결정 방식을 MANCOVA 비교분석한 결과 성과정보의 제공은 응답자들의 예산배분 행태의 차이를 유발하는 주요한 요인인 것으로 나타났다. 일반행정 분야의 경우 두 개 프로그램에서 연구집단과 대조집단의 예산배분 방향성에 차이가 나타났으며 나머지 두 개 시나리오에서는 동일한 방향성을 지니면서도 증액의 규모와 비율에 있어 대부분 유의미한 차이가 도출되었다. 이러한 결과를 토대로 성과정보 활용에 따른 일반적 의사결정 모형을 구축하기 위해 후속 연구에서 전문성의 편향 문제를 극복하기 위해 반복적인 실험 연구와 관료집단과 일반인의 행태를 비교-검증하는 연구를 수행할 것을 제안한다.

• 한방안이비인후피부과학회지
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• 제21권2호
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• pp.19-27
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• 2008

Objective : The side effect of prolonged use of topical corticosteroids to skin is well-known. Moreover, resent studies have shown that prolonged use of systemic corticosteroids also negatively impacts skin barrier function. Corticosteroids have a major role in the practical management of many variable conditions. So, it is important to find the drug or the method which could protect the skin from the damage caused by corticosteroids. At former study, we investigated that Insamyangyoung-tang has some effect on skin barrier function of DNCB induced contact dermatitis hairless mice. So, this study was performed to research the effect of Insamyangyoung-tang on the TEWL with high dose steroid injected hairless mice. Method : Hairless mice were divided into 4 groups ; Control group, Group A, Group B and Group C. All groups were injected triamcinolone O.4mg for 10 times. Control group was medicated distilled water during the experimental period. Group A was medicated distilled water for 5 days before the $1^{st}$ injection day, and then medicated Insamyangyoung-tang extract during the experimental period. Group B was medicated Insamyangyoung-tang extract for 5 days before the $1^{st}$ injection day, and then medicated distilled water during the experimental period. Group C was medicated Insamyangyoung-tang extract for 5 days before the $1^{st}$ injection day, and then medicated Insamyangyoung-tang extract during the experimental period. TEWL of each group was measured for 5 times. After the $10^{th}$ injection, the tissue sample was made and the damage of epithelial cell was examined. Statistical significance was set at p<0.05 by using non parametric methods and repeated-anova.. Results : Group C showed significant effect on TEWL change of hairless mice evoked by triamcinolone injection. Group A and Group B also showed some effect, but there was no statistical significance.

• 환경영향평가
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• 제19권3호
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• pp.357-365
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• 2010

This study evaluated current status of marine sand mining and related assessment systems in Korea for supporting effective policy development. The estimated total deposit of sand was ca. 10 billion $m^3$, while the estimated minable amount was ca. 5.5 billion $m^3$, in which marine sand accounted for 21%. The proportion of marine sand to the total mined aggregates has steadily increased by 15% in 1992 to 28% in 2002, but recently slightly decreased. Marine sand mining is regulated under a consultation system on the coastal development according to the "Marine Environmental Management Act". During 2002-2009, a total of 184 million $m^3$ of marine sand was mined, and the annual amount ranged from 17,440,000-33,698,000 $m^3$ the coastal area accounted for 64.5% and the Exclusive Economic Zones (EEZs) 35.5%. In the coastal area, the major area supplying the marine sand was Gyeonggi Bay (>62%) followed by some southwestern coastal areas. The South and the West EEZ explained 23.9% and 11.6% of the total mined sand. The extent of marine sand mining in Korea was evaluated to be greater compared with other countries. Large-scale concentrated and repeated sand mining can damage environmental changes and ecology with long-term accumulated impacts.