• Journal of Electrical Engineering and Technology
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• 제10권6호
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• pp.2256-2261
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• 2015

In the power plant using high temperature fuel cells such as Molten Carbonate Fuel Cell(MCFC), and Solid Oxide Fuel Cell(SOFC), the generated electric power per area of power generation facilities is much higher than any other renewable energy sources. - High temperature fuel cell systems are capable of operating at MW rated power output. - It also has a feature that is short for length of the line for connecting the interior of the generation facilities. In normal condition, these points are advantages for voltage drops or power losses. However, in abnormal condition such as fault occurrence in electrical system, the fault currents are increased, because of the small impedance of the short length of power cable. Commonly, to minimize the thermal-mechanical stresses on the stack and increase the systems reliability, we divided the power plant configuration to several banks for parallel operation. However, when a fault occurs in the parallel operation system of power main transformer, the fault currents might exceed the interruption capacity of protective devices. In fact, although the internal voltage level of the fuel cell power plant is the voltage level of distribution systems, we should install the circuit breakers for transmission systems due to fault current. To resolve these problems, the SFCL has been studied as one of the noticeable devices. Therefore, we analyzed the effect of application of the SFCL on bus tie in a fuel cell power plants system using PSCAD/EMTDC.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권4호
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• pp.1-9
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• 2022

This study was conducted to supplement new-normal strategies on management plans of rural groundwater resources in the era of Post COVID-19. Global outbreak of COVID-19 has damaged across all areas including public policy, economics, industrial services, and others without exception, which has resulted in establishing new-normal strategies in order to restore balance and functions as for these areas. The new-normal ones were represented as enhancing preventative management on infectious diseases, expanding non face-to-face services, enhancing protective trades and food securities, and preparing growth policies on public services using the 4^th industrial revolution techniques. In this study, G-WASH_AD (Groundwater supply, sanitation, and hygiene with attraction and digitization) was suggested to be new-normal strategies on rural groundwater resources. The G-WASH_AD was consisted of three detailed action plans: a preventative plan on waterborne-diseases of groundwater (PP), a groundwater-tourism plan with rural heritage (GP), and an application plan of the 4^th industrial revolution techniques to groundwater facilities and its data (P4). The PP can contribute to protect human health from waterborne-diseases and minimize hazardous effects on crop cultivation. The GP accompanied with high-quality groundwater resources is able to strengthen rural tourism, to promote marketing activities on local agricultural products, and to increase household incomes of rural communities. The P4 can reinforce fast, comfortable, and scientific management on groundwater facilities and its data, creating a virtuous cycle between innovative management on groundwater and growth of technology related to it. Results of the G-WASH_AD strategies can encourage a green growth engine in field of rural groundwater management keeping up with Post COVID-19.

• Annals of Occupational and Environmental Medicine
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• 제34권
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• pp.29.1-29.14
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• 2022

Background: Hotel housekeepers are one of the most important occupational group within tourism hotel sector; various health problems related to their job have been described, above all musculoskeletal disorders. The objective of this study is to understand the experiences and perceptions of hotel housekeepers and key informants from the Balearic Islands (Spain) regarding occupational health conditions and the strategies employed to mitigate them. Methods: A qualitative study was carried out. Six focus groups with hotel housekeepers and 10 semi-structured interviews with key informants were conducted. Next, we carried out a content analysis. Results: Hotel housekeepers reported musculoskeletal disorders, anxiety and stress as main occupational health problems; health professionals underscored the physical problems. Hotel housekeepers perceived that their work (physically demanding and with repetitive movements) caused their health conditions. To solve health issues, they used medication (anti-inflammatory agents, painkillers, sedatives and anxiolytics), which allowed them to continue working; health public services, generally rated as satisfactory; individual protective equipment; ergonomics (with difficulties due to high work pace and hotel facilities) and physical activity. Two contrasting attitudes were identified regarding sick leave: HHs who refused to accept a doctor-prescribed sick leave (due to fear of being fired, sense of responsibility, ...), and those who accepted it (because they could not continue working, they prioritised health before work). Conclusions: Our results might contribute to plan improvement strategies and programs to address health problems among hotel housekeepers. These programs should include interventions, such as coping strategies for the work-related risk factors (i.e., stress) and strategies to reduce medicine consumption. Additionally, hotel facilities should adopt policies focused on making workplaces more ergonomic (i.e., furniture) and to diminish the work pace.

• 한국환경보건학회지
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• 제43권1호
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• pp.42-54
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• 2017

Objectives: The present study was conducted to investigate farm work environments among farmers and examine the level of management of safety and health, and to subsequently produce study result to serve as foundational data for the development of guidelines on safety and health as part of the improvement of farming work environments among farmers raising Korean native cattle. Methods: The present study conducted a survey on farm work environments and the management of safety and health with 407 farmers engaged in Korean native cattle farming in selected regions in eight provinces. It also visited 10 farmers to verify the current status of farm work. Results: The survey results showed that 16.4% of the respondents experienced safety-related accidents due to farm work. The locations of the accidents were inside the cattle shed (71.4%) and facilities outside the cattle shed (19.6%). The types of accident showed collision with animals (35.7%), collision or contact with obstacles (27.1%), and musculoskeletal accidents due to heavy object handling (12.9%). The causes of the accidents were cattle (38.3%), cultivators and tractors (25.4%), facility tools in cattle sheds (9.0%), and slippery floors (6.0%). The damaged areas were hand (21.0%), spine (19.8%), lower limb (18.5%), and foot (17.3%). A self-diagnostic survey on respiratory diseases showed that 11.5% of the respondents experienced respiratory-related symptoms. The survey on safety and health during farm work showed that wearing personal protective equipment and response to emergency situations, which were needed to prevent safety-related accidents, were relatively low compared to the level of recognition of the need and awareness of safety issues. Furthermore, the field survey identified the current status of safety and health issues such as prevention management of collision accidents with cattle, how to handle heavy objects, and wearing of personal protective equipment. Conclusions: The present study identified safety-related accidents and problems in the management of safety and health among Korean native cattle farmers. In order to address the problem, it is necessary to not only provide guidelines on safety and health management which are appropriate to the characteristics of Korean native cattle farming work, but also to study the development of personal protective equipment.

• 한국융합학회논문지
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• 제2권4호
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• pp.29-37
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• 2011

종래의 배전계통에 있어서의 전력조류는 변전소에서 선로말단을 향한 단 방향이었지만, 신에너지전원(분산전원)이 연계된 배전계통의 경우에는 그 출력용량의 여부에 따라 양방향의 전력조류가 발생할 가능성이 있어, 계통운용상 여러 가지의 문제점이 야기될 수 있다. 분산전원은 대규모전원의 보완적 역할과 배전선로 상의 국부적 부하 감당 역할을 부과하여 그의 적극적 활용을 꾀하기 위해서는, 분산전원으로부터 배전계통에 전력을 공급하는 역 조류의 기능을 허용할 수 있는 양방향 보호협조방식의 체제를 확립할 필요가 있다. 따라서 본 연구에서는 분산전원 연계에 따른 보호협조 기본 방안과 부하절체 운전에 따른 보호협조 방안, 변압기결선에 따른 보호협조 방안 등에 대한 알고리즘을 제시하였다. 또한, 이론적인 계산법(대칭좌표법)과 MATLAB/SIMULINK에 의하여 실 계통에서의 양방향 보호협조에 관련된 문제점을 분석하고, 해결방안을 제시하였다.

• 디자인융복합연구
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• 제15권3호
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• pp.171-186
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• 2016

지속적인 노인인구의 증가와 고령화가 급속하게 진행되면서 지역 내 노인복지관은 지역주민의 다양한 욕구를 충족시키는 대표적인 서비스 공간으로 그 중요성이 높아지고 있다. 또한, 과거세대에 비해 높은 학력수준, 경제능력의 향상, 가치관과 라이프스타일이 변화됨에 따라 이전 세대와는 다르게 양질의 서비스를 추구하는 성향이 나타나고 있다. 이에 본 연구에서는 노인 연륜적 특성 지표인 라이프스타일 측정도구를 사용하여 노인의 라이프스타일 유형에 따른 노인복지관의 만족도를 분석하였다. 본 연구는 서울에 위치한 7곳의 노인복지관 이용자를 대상으로 설문조사를 실시하였다. 조사결과 첫째, 군집분석을 통해 라이프스타일 유형을 독립활동형, 보호활동형, 적극도전형, 소극도전형으로 분류하였다. 둘째, 노인의 라이프스타일에 따른 노인복지관의 전반적인 만족도는 보호활동형이 가장 높게 나타났으며 그 다음으로는 소극도전형, 적극도전형, 독립활동형의 순으로 나타났다. 셋째, 노인의 라이프스타일 유형별로 노인복지관의 공간특성이 만족도에 미치는 영향을 살펴본 결과 독립활동형과 소극도전형은 친밀성, 보호활동형은 쾌적성, 적극도전형은 편의성이 가장 영향력이 큰 것으로 조사되었다.

• 한국사회복지학
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• 제43권
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• pp.42-75
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• 2000

Violence against women includes sexual violence, domestic violence, trafficking, etc. It is a serious problem that violates women's rights and basic freedom. In Korea, with the enactment of the laws on sexual violence and domestic violence in the 1990s, counseling centers and protective facilities for the victims began to be established and have been rapidly increasing in number recently. The purpose of this research was to investigate the current status of the counseling services with a focus on their linkage function. 78 out of 109 counselors working in the counseling centers for sexual and domestic violence throughout Korea responded to a mail survey. The questions included the general characteristics of the centers and the counselors, the structural, relationship and process dimensions of linkage function, and the subjective and objective aspects of the degree of linkage. The findings of the analysis highlighted the following problems. First, the counseling centers played limited role in serving the victims of violence due to lack of resources in the service network. Second, the linkage of services existed on a relatively small scale which was mostly based upon informal and unstructured relationship. Third, according to the multivariate analysis, the existence of potential partner agencies, the effort of the line staff to initiate the linkage relationship and mutual cooperation between agencies determined the degree of linkage among services. These findings suggest implications for establishing a more effective system to protect the victims of violence.

• 대한가정학회지
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• 제43권2호
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• pp.143-158
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• 2005

The purpose of this study was to determine the protective factors that strengthen the adaptation ability by analyzing individual, family, and social activities variables which impact on the adjustment of retired men. The sample for final data analysis was 233 questionnaires completed by retired men aged from 45 to 65 years living in Seoul and the Metropolitan area. Statistical analyses were carried out using SPSS/WIN which included Frequencies, t-test, one-way ANOVA, and regression analysis. The results were as follows: 1. The degree of the retired men's adaptation was 3.22 out of 5. 2. The retired men's adaptation was affected by the variables in the following order: marital satisfaction, economic life satisfaction, acceptance for retirement, recreational facilities satisfaction, recognition for retirement, and cohesion. These variables explained 65.3% of the retired men's adaptation to life. The findings of this study could be utilized as basic data for developing educational programs and guiding policy-making to help retired men achieve development.

• 수산해양교육연구
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• 제12권2호
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• pp.164-175
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• 2000

Port facilities and marine structures used in marine environment were encountered to corrosion damages because of the influence of Cl-. Generally, to protect these accidents, anti-corrosion paint and epoxy coating have been used. But they were still remained erosion-corrosion damage like impingement erosion, cavitation erosion and deposit attack. It is necessary to develope the new composite lining material in order to protective those corrosion damages. In this paper, polyester glass flake, vinylester glass flake lining and epoxy coating for SS400 were investigated by the electrochemical polarization test and the impingement-cavitation erosion test for corrosion behaviour under the sea water. The main results obtained are as follows ; 1) Epoxy coating appear potentiodynamic polarization behaviour, but polyester glass flake and vinylester glass flake lining do not appear potentiodynamic polarization behaviour. 2) Open circuit potential of polyester glass flake lining is more noble than that of epoxy coating and corrosion current density of polyester glass flake lining is less drained than that of epoxy coating in sea water. 3) Open circuit potential of vinylester glass flake lining is more noble than that of polyester glass flake lining and corrosion current density of vinylester glass flake lining is less drained than that of polyester glass flake lining in the sea water.

• 조명전기설비학회논문지
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• 제29권1호
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• pp.103-112
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• 2015

Recently, DC distribution system has come into the spotlight as the number of digital loads and the use of renewable energy increases. However, there are still challenges for the commercialization of DC distribution system such as a consideration for the safety. Thus, researches on protective coordination and grounding system for the safety of human bodies and facilities in Low-Voltage DC (LVDC) distribution system should be preferentially conducted. In this paper, therefore, we analyze characteristics of faults in LVDC system accroding to type of grounding system based on IEC 60364. Finally, the simulations for fault characteristic in different grounding scheme are conducted using ElectroMagnetic Transient Program(EMTP) and the results of simulation are shown.