• Journal of Electrical Engineering and Technology
• /
• 제7권5호
• /
• pp.659-663
• /
• 2012

The application of large power transformer into a power distribution system was inevitable due to the increase of power demand and distributed generation. However, the decrease of the power transformer's impedance caused the short-circuit current of the power distribution system to be increase thus, the higher short-circuit current exceeded the cut-off ratings of the protective devices such as circuit breaker. To solve these problems, several countermeasures have been proposed to protect the power system effectively from higher fault current and the superconducting fault current limiter (SFCL) has been expected to be the promising countermeasure. In spite of excellent current limiting performances of the SFCL, on the other hand, the efforts to apply the SFCL into power system has been delayed due to both the limited spaces for the SFCL's installation and its long recovery time after the fault removal. In order to solve these problems, a hybrid SFCL, which can perform either first half cycle limiting of first half cycle non-limiting operation, has been developed by corporation of LSIS (LS Industrial System) and KEPCO (Korea Electric Power Corporation). In this paper, we tried to requirements hybrid SFCL by PSCAD/EMTDC. Simulation results of our analysis of the hybrid SFCL is that its accompanied the characteristics both the limit the fault current and quick recovery caused by the less impact from superconductor.

• 한국실내디자인학회논문집
• /
• 제27권3호
• /
• pp.49-61
• /
• 2018

Korea achieved compressed growth through rapid industrialization. However, the housing policy of this period was driven by the provision of large scale public rental housing and redevelopment of residential areas, resulting in community collapse and social exclusion. Meanwhile, Korean society needs new housing types and management methods as housing demand varies due to low birthrate, aging, and growing numbers of single-person households. Therefore, in order to realize social integration community that solves these problems by themselves, it is necessary to plan housing that can enhance community in residential space. In this reason, the purpose of this study is to derive the characteristics of social integration plan of community housing which is supplied mainly in the metropolitan area. Accordingly, the subjects of this study were housing cases designed to enhance social integration by promoting community activation in Seoul and Gyeonggi-do. The results of this study are as follows: First, it is necessary to flexibly apply the type and range of community housing. Second, It is needed to have a housing plan considering various characteristics of resident community. Third, social integrated community housing requires not only physical planning, but also mechanism to operate it.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
• /
• 제5권10호
• /
• pp.353-360
• /
• 2016

여러 개의 태양전지들이 붙어 있는 태양광 패널을 이용하여 전력을 생산하는 태양광 발전은 최근 신재생 에너지 기술로 빠르게 성장하고 있는 분야이다. 하지만 태양광발전의 단점 중 하나인 불규칙한 전력 생산문제로 인해, 장비 및 패널 결함에 빠르게 대응하지 못하는 문제가 발생한다. 이 연구에서는 다양한 기후데이터와 패널 정보를 이용하여 태양광발전량 예측 방법들을 비교하여 최적의 예측 알고리즘을 평가하고 이를 기반으로 태양광발전소 결함 검출 시스템을 개발하여 국내 태양광 발전소에 적용한 사례를 기술한다.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2002년도 제9차 국제심포지움 및 추계정기학술발표회
• /
• pp.12-12
• /
• 2002

The chlorophyll fluorescence combined with the O-J-I-P transients were examined in the leaves of the crinum plants (Crinum asiaticum var. japonicum BAK.), in order to satisfy the demand for rapid in vivo measurement of vitality, and to apply easily to approach questions of economical interest concerning the plant vitality. The photosynthetic efficiency, Fv/Fm, of crinum plants dramatically decreased depending on temperature drop in winter. In summer, the Fv/Fm values was lower in day time than at dawn and night, suggesting that photosynthetic efficiency is chronically photoinhibited in day time. In winter, there was no prominent diurnal fluctuations of Fv/Fm values. However, based on the O-J-I-P transient, PI$\_$NO/ and SFI$\_$NO/ dramatically increased at noon in summer, and $\psi$o/(1-$\psi$o) diurnally fluctuated in winter. These results indicated that vitality indexes such as PI$\_$NO/, SFI$\_$NO/ and $\psi$o/(1-$\psi$o) can be used as the indicators for in vivo measurement of environmental stresses.

• 한국실내디자인학회논문집
• /
• 제21권6호
• /
• pp.129-136
• /
• 2012

As the importance of eco-friendly and energy saving issues are emphasized in lighting as consciousness about energy saving is elated worldwide, demand for natural resources such as gas increases, supply of LED lighting is spread. Owing to white LED's development and price fall. It is expected to LED High Luminance Emitting Diode. LED's brightness and long life-time that surpass fluorescent light in the latest as well as is used by back light source of thin film LCD, low electric power attrition rate by advantage do and widen the market at the world lighting lamp market that is potential market. Accordingly, study about suitability of LED lighting is activated but space that apply actual LED lighting fixtures yet is less and advanced researches about LED fixtures' applied apaces are slight compared to existing light source up to now because is not many on this. The result of the experiment shows similar tendency with the existing light sources'. Through a psychological reaction experiment in the LED lighting experiencing space that can control of color temperature and lighting level, this study is wished to use to the data for lighting design of space that LED lighting fixtures are applied hereafter.

• 복식
• /
• 제58권9호
• /
• pp.166-175
• /
• 2008

For the structural firefighting protective clothing, it can show a synergy effect when it satisfies smart fabric to block off a harmful environmental element and ergonomics design that apply range of motion of human body and appropriate size system. There are various standards about the structural firefighting protective clothing, but it's difficult to find a rule about movement suitability because the performance of the material holds a lot of the rules. Therefore, the purpose of this study is to propose a scheme to evaluate the current structural firefighting protective clothing and to improve movement suitability by research on the actual condition. For this, the survey about wearer acceptability scale on design and size and about improvement requirements was executed gathering firefighters' opinion. Questionnaire was composed with 23 items about satisfaction on current structural firefighting protective clothing, body suitability, movement suitability, improvement requirement and subjective information. As a results, Korean firefighters demand ergonomics design of structural firefighting protective clothing which to minimize restriction of body movement and to maximize body suitability.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2002년도 심포지엄
• /
• pp.88-95
• /
• 2002

The chlorophyll fluorescence combined with the O-J-I-P transients were examined in the leaves of the crinum plants (Crinum asiaticum var.japonicum BAK.), in order to satisfy the demand for rapid in vivo measurement of vitality, and to apply easily to approach questions of economical interest concerning the plant vitality. The photosynthetic efficiency, Fv/Fm, of crinum plants dramatically decreased depending on temperature drop in winter. In summer, the Fv/Fm values was lower in day time than at dawn and night, suggesting that photosynthetic efficiency is chronically photoinhibited in day time. In winter, there was no prominent diurnal fluctuations of Fv/Fm values. However, based on the O-J-I-P transient, PI$\_$NO/ and SFI$\_$NO/ dramatically increased at noon in summer, and $\psi$ο/(1-$\psi$ο) diurnally fluctuated in winter. These results indicated that vitality indexes such as PI$\_$NO/, SFI$\_$NO/ and $\psi$ο/(1-$\psi$ο) can be used as the indicators for in vivo measurement of environmental stresses.

• 제어로봇시스템학회논문지
• /
• 제21권11호
• /
• pp.989-995
• /
• 2015

Due to the recent increase of the importance and demand of security services, the importance of a surveillance monitor system that makes an automatic security system possible is increasing. As the market for surveillance monitor systems is growing, price competitiveness is becoming important. As a result of this trend, surveillance monitor systems based on an embedded system are widely used. In this paper, an object detection algorithm based on an embedded system for a surveillance monitor system is introduced. To apply the object detection algorithm to the embedded system, the most important issue is the efficient use of resources, such as memory and processors. Therefore, designing an appropriate algorithm considering the limit of resources is required. The proposed algorithm uses two background models; therefore, the embedded system is designed to have two independent processors. One processor checks the sub-background models for if there are any changes with high update frequency, and another processor makes the main background model, which is used for object detection. In this way, a background model will be made with images that have no objects to detect and improve the object detection performance. The object detection algorithm utilizes one-dimensional histogram distribution, which makes the detection faster. The proposed object detection algorithm works fast and accurately even in a low-priced embedded system.

• 한국직업건강간호학회지
• /
• 제14권1호
• /
• pp.44-55
• /
• 2005

Purpose: The purpose of this study was to describe the current status of work-related back pain among nurses in the U.S. Method: Literature review and website searching were conducted. Key words as 'nurse and back pain (or back injury)' were used in searching the Medline, NIOSHTIC-2and reference list of selected studies. Total studies were selected of which subjects were nurses working in the U.S., and published since 1970. Results: Though there was variation in the measurement among studies, the prevalence rate of back pain among nurses in the U.S. could be estimated about 50%. Risk factors were confirmed as the frequency of patient lifting, ward, nursing shortage, overtime, work shift, stress on physical demand, but age and work experiences showed the inconsistent relation. It has been well known that educational approach is not enough to prevent back pain. Intervention studies to apply the ergonomic approach using mechanical devices reported the effects, but the devices were less diverse than European countries or Canada. The study for lifting team was rare. Federal government developed only the guideline for nursing home that had no legal obligation. As a professional nursing organization, ANA has been trying to educate and advocate for "No lift policy" since 2003. Meanwhile, two trade unions of nurses made efforts to establish the law strengthening the responsibility of health care facilities. Conclusion: The research and policy development will be needed to prepare to rapid increase of back pain among Korean nurses.

• 한국건축시공학회지
• /
• 제4권1호
• /
• pp.111-118
• /
• 2004

The need for this study must be considerable. as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction. which have enormously large impact on the durability.