• 제목/요약/키워드: Investigation of Origin

검색결과 242건 처리시간 0.028초

조명등 화재사례 연구(전구 및 형광등 중심으로) (A Case Study on the Lights Fire(Focus on the Electric Bulbs and Fluorescent Lamps))

  • 송태현;이의평
    • 한국화재조사학회논문지
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    • 제11권1호
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    • pp.41-58
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    • 2008
  • 등불의 발견은 인간 생활에 커다란 변화를 가져 왔으며, 그 역사는 매우 오래되었다. 그러나 비약적으로 발전한 것은 1879년 에디슨이 탄소 필라멘트 진공 전구를 발명하여 조명에 사용하면서 시작되었다고 할 수 있다. 조명은 피로를 덜어주고 안전도를 높이며 사람의 활동 능률을 올리고 즐거운 분위기를 만들어 준다. 그러나 부주의나 관리소홀로 인해 소중한 재산과 인명을 앗아가는 화재의 원인이 되기도 한다. 본 연구에서는 조명등의 구조와 원리를 이해하고 일반가정에서 가장 많이 사용되고 있는 백열전구과 형광등을 중심으로 출화가능성과 조사확인사항에 대하여 발화사례를 중심으로 하여 배선과 가연물 접촉에 의한 사례 및 재현실험을 통하여 논문의 신뢰성을 확보하고자 하였다.

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Investigation of field emission mechanism of undoped polyucrystalline diamond films

  • Shim, Jae-Yeob;Chi, Eung-Joon;Song, Kie-Moon;Baik, Hong-Koo
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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    • pp.62-62
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    • 1999
  • Carbon based materials have many attractive properties such as a wide band gap, a low electron affinity, and a high chemical and mechanical stability. Therefore, researches on the carbon-based materials as field emitters have been drawn extensively to enhance the field emission properties. Especially, diamond gives high current density, high current stability high thermal conductivity durable for high temperature operation, and low field emission behaviors, Among these properties understanding the origin of low field emission is a key factor for the application of diamond to a filed emitter and the verification of the emission site and its distribution of diamond is helpful to clarify the origin of low field emission from diamond There have been many investigations on the origin of low field emission behavior of diamond crystal or chemical vapor deposition (CVD) diamond films that is intentionally doped or not. However, the origin of the low field emission behavior and the consequent field emission mechanism is still not converged and those may be different between diamond crystal and CVD diamond films as well as the diamond that is doped or not. In addition, there have been no systematic studies on the dependence of nondiamond carbon on the spatial distribution of emission sites and its uniformity. Thus, clarifying a possible mechanism for the low field emission covering the diamond with various properties might be indeed a difficult work. On the other hand, it is believed that electron emission mechanisms of diamond are closely related to the emission sites and its distributions. In this context, it will be helpful to compare the spatial distribution of emission sites and field emission properties of the diamond films prepared by systematic variations of structural property. In this study, we have focused on an understanding of the field emission variations of structural property. In this study, we have focused on an understanding of the field emission mechanism for the CVD grown undoped polycrystalline diamond films with significantly different structural properties. The structural properties of the films were systematically modified by varying the CH4/H2 ratio and/or applying positive substrate bias examined. It was confirmed from the present study that the field emission characteristics are strongly dependent on the nondiamond carbon contents of the undoped polycrystalline diamond films, and a possible field emission mechanism for the undoped polycrystalline diamond films is suggested.

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음식점 원산지표시 시행에 대한 호텔조리직원들의 지식에 관한 연구 (A Study on Knowledge of Country-of-Origin Labeling System in Hotel Culinary Staffs)

  • 권기완;정유경
    • 한국조리학회지
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    • 제21권3호
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    • pp.155-167
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    • 2015
  • 본 연구는 음식점 원산지표시에 대한 조리직원들의 지식 정도를 파악하고 평가할 수 있는 도구를 개발하여, 조리직원들이 음식점 원산지 표시제도에 대해 어느 정도 지식을 갖추고 있는지 파악하는데 목적을 두고 있다. 실증연구는 편의 표본추출법으로 서울소재 특급호텔 10곳에 재직 중인 7년차 이상의 조리직원들을 대상으로 2014년 11월 14일부터 11월 27일까지 14일간 진행되었으며, 설문지는 자기기입식방법으로 총 200부의 설문지를 배포하여 이중 192부를 회수하였으며, 최종 186(93 %)부를 연구 자료로 사용하였다. 조사 분석을 위해 SPSS 18.0 통계 프로그램을 활용하여 인구통계사항과 지식정도를 알아보기 위해 빈도분석을 실시하였으며, 조리직원들의 학력, 직급, 경영형태에 따른 음식점 원산지표시의 지식 차이를 알아보기 위하여 일원분산분석과 t-test 분석을 실시하였다. 조리직원들에게 음식점 원산지표시에 대한 지식을 조사한 연구결과, 전체 21문항에 대한 평균 정답률은 39.85%로 매우 낮게 조사되었고, 학력은 유의한 차이가 없었으나, 직급은 높을수록, 경영형태는 독립경영호텔이 높은 점수를 보여 조리직원들의 지식은 직급과 경영형태에 따라 차이가 있는 것으로 조사 되었다. 연구결과 향후 음식점 원산지표시에 대한 조리직원의 지식수준을 높이기 위하여 교육을 강화하여야 하며, 이를 업무에 적용할 수 있도록 지속적인 관리 감독을 해야 할 것으로 사료된다. 연구의 한계 및 향후 연구방향에 대해서도 논의 하였다.

사례를 통한 화재사(火災死)의 이해 (A Study on the Possibility of Ignition by Disposable Lighter)

  • 제진주;이창우;권현석;손정배;이정일;최돈묵
    • 한국화재조사학회지
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    • 제10권1호
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    • pp.59-75
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    • 2007
  • 산업화 이전의 화재사망자의 사망원인은 대부분 화염접촉에 의한 열화상이었다. 그러나 1990년대 이후 획기적으로 경제가 발전함에 따라 주거주공간이 대형화, 복잡화되고 내장재가 고급화되고 있다. 그러므로 최근의 화재에서는 열화상에 의한 사망보다 유독가스 흡입에 따른 질식 사망자가 대부분을 차지하고 있다. 또한 보험범죄가 증가하면서 보험금 등 경제적 이익을 사취하기 위한 방화로 인한 사망자가 크게 증가하고 있다. 소방방재청 발표에 의하면 2006년 전국적으로 31,778건의 화재가 발생하여 총 2,180명의 사상자가 발생하였고 이중 446명의 귀중한 인명이 사망하였다. 특히, 화재사망자가 발생한 화재는 민 형사상의 분쟁요인으로 작용할 수 있으므로 정확한 화재원인 및 사망원인 조사의 중요성이 강조되고 있다. 그러므로 본 연구에서는 최근 전국화재 통계를 중심으로 화재원인별, 발생장소별, 연령별 사망자를 분석하고 화재사의 감식 방법 및 화재 시 인간행동 특성, 화상사, 질식사 및 화재사 등의 원인을 중점으로 고찰하고 한다.

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A Nasal Myiasis in a 76-Year-Old Female in Korea

  • Kim, Jae-Soo;Seo, Pil-Won;Kim, Jong-Wan;Go, Jai-Hyang;Jang, Soon-Cheol;Lee, Hye-Jung;Seo, Min
    • Parasites, Hosts and Diseases
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    • 제47권4호
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    • pp.405-407
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    • 2009
  • On July 2009, 5 fly larvae were discovered inside the nose of a 76-year-old female. She was living in Cheonansi, and in a state of coma due to rupture of an aortic aneurysm. Surgery was performed on the day of admission, and the larvae were found 4 days later. By observing their posterior spiracle, the larvae were identified as Lucilia sericata. Considering the rapid development of this species, the infection was likely acquired during hospitalization. Further investigation on the hospital environment should be needed to know the origin of the infection.

Analysis of the Singular Point of Cyclic Voltammograms Recorded with Various Scan Rates

  • Chang, Byoung-Yong
    • Journal of Electrochemical Science and Technology
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    • 제8권3호
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    • pp.244-249
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    • 2017
  • This paper presents the results of an investigation into the isoamperic point of cyclic voltammograms, which is defined as the singular point where the voltammograms of various scan rates converge. The origin of the unique point is first considered from a theoretical perspective by formulating the voltammetric curves as a system of linear equations, the solution of which indicates that a trivial solution is only available at the potential at which the net current is zero during the reverse potential scan. In addition, by way of a mathematical formulation, it was also shown that the isoamperic point is dependent on the switching potential of the potential scanning. To validate these findings, theoretical and practical cyclic voltammmograms were studied using finite-element based digital simulations and 3-electrode cell experiments. The new understanding of the nature of the isoamperic point provides an opportunity to measure the charge transfer effects without the influence of the mass transfer effects when determining the thermodynamic and kinetic characteristics of a faradaic system.

A Theoretical Study of Gas-Surface Phonon Scattering: Model He-Si(100) Bulk and Reconstructed Surfaces

  • Seung Chul Park;Chang Hwan Rhee;Woong Lin Hwang;Yoon Sup Lee;Myung Soo Kim
    • Bulletin of the Korean Chemical Society
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    • 제12권4호
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    • pp.387-392
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    • 1991
  • We present a theoretical investigation of the inelastic atom-surface phonon scattering for a model He-Si(100) system by the classical trajectory-quantum forced oscillator(DECENT) method. Single and multi-phonon transition probabilities of normal modes are calculated for several initial beam orientations and several initial kinetic energies. In order to understand surface structure effects, the calculation has been done on both reconstructed and unreconstructed surfaces of the He/Si(100) system. The origin of mode specificity for energy transfer is discussed. The contribution of one, two, and multi-phonon events to the total energy transfer between 0 and 600 K is also given.

동서양(東西洋)의 패션 커뮤니케이션에 관(關)한 연구(硏究) (A Study on the Fashion Communicating of The East and The West)

  • 전혜정
    • 패션비즈니스
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    • 제1권3호
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    • pp.82-94
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    • 1997
  • The purpose of this study is to focus on the fashion communicating of the East and the west. For this purpose, the study will analyze the Visions of the East in Western Dress has long expressed an intense multiculturalism. This study is realized that clothing has served to consolidate more then to segregate. While never losing the characteristics of its place of origin, clothing has shown itself a reading assimilated object portability and ephemerality promote investigation, at the very least. Eastern ideas of textile, design, construction, and utility has been realized again as a positive contribution to the culture of the West. The East offers a larger concept in alternative to the Western propensity for tailoring. In giving primacy to the textile, Eastern dress emphasizes the flat terrain of cloth, the looping and Wrapping of the garment, and the integrity of the untailored textile. There values, antithetical to postmedieval Western dress, have offered a paradigm of dressing and dressmaking to the West that has been sporadically Influential, and notably so in our time.

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신경모세포종 (Neuroblastoma)

  • 강형진;유경하;신희영;안효섭
    • Advances in pediatric surgery
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    • 제14권1호
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    • pp.75-82
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    • 2008
  • Neuroblastoma arises from the primitive neural crest cells, and is a common malignancy in childhood. The clinical features are characterized by biological heterogeneity. Neuronal degeneration and differentiation occur in some patients. However treatment in the high risk group accounting for approximately half, has not been satisfactory despite a multimodal approach. Therefore, effective treatment is determined by the risk group of prognostic factors, such as age at diagnosis, stage of disease, pathological finding and N-myc amplification. Neuroblastoma can be diagnosed prenatally, which suggests its origin during the normal embryogenesis. Recent knowledge of molecular biology, such as Trk genes, and the concept of cancer stem cells have given us some improved understanding on this disease. Currently, targeted therapies based on the molecular biology of neuroblastoma are under investigation and increasing survival rate and decreasing late complications could be appreciated.

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노동재해에 대한 산업심리학적 고찰 (An Industrial Psychological Study On Labor Accidents)

  • 현영기
    • 산업경영시스템학회지
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    • 제3권3호
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    • pp.41-48
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    • 1980
  • Industrial Psychology is to study and analyze human behavior or working at operation, both to look into the rules in that and to make analysis of rules made from theological basis adapted to reality, wi th methods and knowledges that Psychology gives, by methods that are observation, experiment , investigation and so on, to contribute to improving the production efficiency and promoting the Laborer's welfare, In this paper, the side of Psychology in labor accidents will be studied as follows. 1.The Presentation of Problems 1.1. Concept prescription of Industrial Psychology 1.2. Relation between Industrial psychology and accidents 2.The Theorical approach of Industrial Psychology for accident study 2.1 Industrial Psychology in approach of accident study 2.2. Cooperative effort from other corvelative science 3. Industrial Psychologic observation on important safety policy 3.1. Study of accident origin 3.2. Safety of material equipment 3.3. Safety of work condition 4. Industrial psychological subject on safety instruction development 4.1. Safety instruction and attitude of laborers 4.2. Operation of safety rules 4.3. Safely counselling 4.4. Measures for the injured 5. Conclusion.

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