• 한국철도학회논문집
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• 제14권5호
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• pp.404-410
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• 2011

AT 방식의 교류 급전시스템에서는 고장점 표정하기 위해 리액턴스 방식과 AT흡상전류비 방식을 채택하고 있다. 하지만 이 방식들은 여러 이유로 인해 표정 오차가 발생할 수 있다. 기존 방식의 이러한 단점을 해결하기 위해 전차선 전류 분류비를 이용하여 고장점을 표정하는 새로운 기법을 제안한다. 전차선 전류 분류비 방식은 기존에 전차선에 연결되어 있는 보호계전기를 사용하여 각 전차선의 전류를 측정하고 취합하여, 그 비(ratio)를 이용하여 고장지점을 표정한다. 이 방식은 기존의 기법보다 더 정확한 고장점을 표정할 수 있으며, 기존의 설치되어있는 계전기를 사용함으로써 추가 설비의 비용을 절감할 수 있다.

• 한국동물위생학회지
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• 제37권4호
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• pp.297-305
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• 2014

Animals and disease frequency of the rescued dogs were investigated in Incheon Veterinary Medical Association Animal Shelter from January in 2012 to December in 2013. Three zoonoses (rabies, brucellosis, and dirofilariosis) and three infectious diseases (canine distemper, canine parvoviral enteritis, and canine influenza) were examined for stray dogs. Among 5,603 heads, 647 (11.5%) went back to their owner and 969 (17.3%) were adopted to new families. Prevalence of dirofilariosis, canine distemper and canine parvoviral enteritis were 2.2% (16/718), 6.0% (24/399) and 6.1% (24/396), respectively. Positive antibody rates against rabies, B. canis and canine influenza virus were 20.5% (41/200), 0.1% (1/718) and 2.0% (4/200), respectively. Protective antibody for canine distemper virus and canine parvovirus were shown in 47.0% (94/200). The data indicate that control measures including facility standards and disease control program are one of the important aspects of the shelter management because stray dogs are exposed to various infectious agents.

• 한국공간구조학회논문집
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• 제4권1호
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• pp.49-59
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• 2004

이전 논문에서 미 중부 및 동남부 지역의 전형적인 다경간 단순효와 다경간 강거더 연속교의 지진 응답을 연구하였으며, 이런 교량에서 덱 사이의 충돌과 큰 연성이 요구되는 기둥은 취약하여 손상을 입을 수 있다는 것을 보여주었다. 더구나, 고정 및 가동 교조장치는 강한 지진운동에 쉽게 피해를 입을 수 있다. 이 논문에서는 몇 개의 개선된 고무 베어링, 납-고무 베어링 그리고 제지선을 사용하여 전형적인 다경간 단순교와 다경간 강거더 연속교의 지진 응답을 평가하였다. 납-고무 베어링은 지진에 취약한 전형적인 교량의 응답을 개선하는데 효과적인 방법으로 평가되었다. 고무 베어링은 기둥의 요구량을 줄이지만, 다경간 단순교 강거더 교량에서 덱 사이의 강한 충돌을 유발시킨다. 제지선은 일반적으로 사용되지만 다경간 단순교와 다경간 연속교의 지진에 대한 손상을 절감하는데 중간정도의 효과를 보여주었다.

• 한국융합학회논문지
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• 제8권6호
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• pp.291-297
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• 2017

본 연구는 감정노동, 직무소진, 목표중심 자기조절 간의 관계에 초점을 둔 대상별 복지 융합연구의 일환으로, 유아교사의 감정노동이 직무소진에 미치는 영향과 이러한 영향이 목표중심 자기조절에 의해 완충되는지의 여부를 규명하고자 하였다. 이를 위해 보육교사 231명을 대상으로 감정노동, 직무소진, 목표중심 자기조절에 관한 설문 조사를 실시하였으며, 자료분석을 위해서는 SPSS(PASW) 18.0과 SPSS용 PROCESS Macro를 사용하여 동시입력방식의 조절회귀분석이 이루어졌다. 연구결과, 첫째, 감정노동 수준이 증가할수록 유아교사의 직무소진도 증가하는 것으로 나타났다. 둘째, 목표중심 자기조절의 경우 감정노동이 직무소진에 미치는 부정적 영향을 완충함으로써 보호기능을 발휘하였다. 이에 본 연구는 유아교사 정신건강 관리의 중요성과 자기조절과 같은 내적자원 개발지원의 필요성을 제안한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 추계학술대회
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• pp.581-584
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• 2011

유도전압이 발생하려면 전력선과 통신선의 적정한 병행거리와 이격거리가 형성되어야 한다. 유도 방지 대책을 수행함에 있어서 이러한 규격 범위를 가능한 최악 조건상에서 고려하여야 할 정량성을 미리 파악해 둘 필요가 있다. 본 논문에서는 특별히 전력선중에서도 실제로 효과가 미약한 것으로 추정되고 있는 지중송 배전선에 대하여 이격거리와 병행거리에 따른 유도전압을 시뮬레이션하여 어느 정도 범위에서부터 유도 대책을 고려하여야 할 지를 추산하여 보았다. 이를 위하여는 전력시설의 파라미터를 조사하여 이격거리에 관하여는 칼슨식에 의하여 계산하고 병행거리에 대하여는 전파연구소고시 제2007-102호에 제시되어 있는 계산식을 기준으로 유도전압 유형별로 수행하였다. 이에 따르면 송전선 잡음전압에 있어서 이격거리 3m의 최악 조건으로서 병행거리 약 13km에서 법적 대책을 수행하여야 할 유도전압이 발생함을 알 수 있다.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.525-532
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• 2016

High-energy linear accelerators are increasingly used in the medical field. However, the unwanted photo-neutrons can also be contributed to the dose delivered to the patients during their treatments. In this study, neutron fluxes were measured in a solid water phantom placed at the isocenter 1-m distance from the head of an18-MV linac using the foil activation method. The produced activities were measured with a calibrated well-type Ge detector. From the measured fluxes, the total neutron fluence was found to be $(1.17{\pm}0.06){\times}10^7n/cm^2$ per Gy at the phantom surface in a $20{\times}20cm^2$ X-ray field size. The maximum photo-neutron dose was measured to be $0.67{\pm}0.04$ mSv/Gy at $d_{max}=5cm$ depth in the phantom at isocenter. The present results are compared with those obtained for different field sizes of $10{\times}10cm^2$, $15{\times}15cm^2$, and $20{\times}20cm^2$ from 10-, 15-, and 18-MV linacs. Additionally, ambient neutron dose equivalents were determined at different locations in the room and they were found to be negligibly low. The results indicate that the photo-neutron dose at the patient position is not a negligible fraction of the therapeutic photon dose. Thus, there is a need for reduction of the contaminated neutron dose by taking some additional measures, for instance, neutron absorbing-protective materials might be used as aprons during the treatment.

• 패션비즈니스
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• 제6권3호
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• pp.28-40
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• 2002

For modern man and woman, footwear is considered a fashion for expressing oneself, and not merely a protective tool for the feet. The purpose of this research is to increase the effect of sales promotional activities by emphasizing product image and by enhancing sales environment. Towards this end, this research focuses on the study of environment at footwear stores that meet the challenges incurred by the changing lifestyles of consumers and the ensuing dynamics of the society in general. Research is based on an in-depth, thorough study of the previous research works and entails examining theoretical background and the concept of Visual Merchandising Display (VMD). Research will focus on the analysis of current situation at footwear stores located in department store based on material research on footwear stores and theoretical examination. Research on the current situation of footwear stores at department store will be conducted from the VMD perspective. In the end, this research paper will make suggestions on the VMD measures for footwear stores with the aim of increasing sales by satisfying consumers' sensibility and purchasing desire. Suggestions will be made based on the results of the research. -Study of current VMD status per fixture centered on 18 brands at department store -Suggestions for VMD at footwear stores based on the survey results of customer purchasing behavior This research intends to develop structured VMD methodology for footwear stores based on the research centered on VMD research of footwear stores at department store. Significance of this research lies in its aim to contribute to the sales increase, no matter how trivial it might be. Going a step further, this research work could be considered one of the foundations for defining the role of VMD methodology at footwear stores. Suggested results are as follows. (1) Need to cast away from simple, one-dimensional type of display method at footwear stores and transform into product image oriented VMD (2) Need to highlight product image by fully leveraging props and by developing footwear display methods that are suitable for different types of fixtures (3) Need to stabilize VMD by developing footwear manual that enables efficient management by store operator.

• 방사선산업학회지
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• 제6권3호
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• pp.223-229
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• 2012

In this study, we investigated the biological damage and stress responses induced by ion beam (proton beam) irradiation as a basis for the development of protective measures against space radiation. We examined the biological effects of proton beam produced by MC-50 cyclotron at KIRAMS on the cultured cells and mice. The proton beam energy used in this study was 34.9 MeV and the absorption dose rate for cells and mice were $0.509Gy\;sec^{-1}$ and $0.65Gy\;sec^{-1}$, respectively. The cell survival rates measured by plating efficiency showed the different sensitivity and dose-relationship between CHO cells and Balb/3T3 cells. HGPRT gene mutation frequency in Balb/3T3 was $15{\times}10^{-6}Gy^{-1}$, which was similar to the reported value of X-ray. When stress signaling proteins were examined in Balb/3T3 cells, $I{\kappa}B-{\alpha}$ decreased markedly whereas p53, phospho-p53, and Rb increased after proton beam irradiation, which implied that the stress signaling pathways were activated by proton beam irradiation. In addition, cellular senescence was induced in IMR-90 cells. In the experiments with C57BL/6 mouse, the immune cells (white blood cells, lymphocytes) in the peripheral blood were greatly reduced following proton beam irradiation whereas red blood cells and platelets showed relatively little change. These results can be utilized as basic data for studying the biological effects of proton beam using MC-50 cyclotron with respect to proton therapy research as well as space radiation research.

• Safety and Health at Work
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• 제2권4호
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• pp.336-347
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• 2011

Objectives: In Korea, an average of 258 workers claim compensation for their noise-induced hearing loss (NIHL) on an annual basis. Indeed, hearing disorder ranks first in the number of diagnoses made by occupational medical check-ups. Against this backdrop, this study analyzed the impact of 19 types of noise-generating machines and equipment on the sound pressure levels in workplaces and NIHL occurrence based on a 2009 national survey on work environments. Methods: Through this analysis, a series of statistical models were built to determine posterior probabilities for each worksite with an aim to present risk ratings for noise levels at work. Results: It was found that air compressors and grinding machines came in first and second, respectively in the number of installed noise-generating machines and equipment. However, there was no direct relationship between workplace noise and NIHL among workers since noise-control equipment and protective gear had been in place. By building a logistic regression model and neural network, statistical models were set to identify the influence of the noise-generating machines and equipment on workplace noise levels and NIHL occurrence. Conclusion: This study offered NIHL prevention measures which are fit for the worksites in each risk grade.

• Safety and Health at Work
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• 제12권3호
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• pp.370-376
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• 2021

Backround: Working condition surveys are widely recognized as useful tools for monitoring the quality of working life and the improvements introduced by health and safety policy frameworks at the European and national level. The Italian Workers' Compensation Authority carried out a national survey (Insula) to investigate the employer's perceptions related to working conditions and their impact on health. Methods: The present study is based on the data collected from the Italian survey on health and safety at work (INSULA) conducted on a representative sample of the Italian workforce (n = 8,000). This focuses on the relationship between psychosocial risk factors and self-reported health using a set of logistic and linear regression models. Results: Working conditions such as managerial support, job satisfaction, and role act as protective factors on mental and physical health. On the contrary, workers' risk perceptions related to personal exposure to occupational safety and health risks, concern about health conditions, and work-related stress risk exposure determine a poorer state of health. Conclusions: This study highlights the link between working conditions and self-report health, and this aims to provide a contribution in the field of health at work. Findings show that working conditions must be object of specific preventive measures to improve the workers' health and well-being.