• 제목/요약/키워드: value at risk

검색결과 946건 처리시간 0.03초

환경 인쇄 기술의 발전과 인쇄물의 $CO_2$ 발생량에 관한 연구 (A Study about Development of Environment Printing Technology and $CO_2$)

  • 이문학
    • 한국인쇄학회지
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    • 제30권3호
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    • pp.89-114
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    • 2012
  • For as to world, the concern about the environment problem is enhanced than any other time in the past because of being 21 century. And the environment problem is highlighted as the world-wide issue. The time of the environment problem intimidates the alive of the mankind and presence of an earth over the time. It becomes the essentiality not being selection in the personal living or the economical viewpoint now to prepare for the climatic modification. As to the company management, the green growth period which it excludes the environment management considering an environment, cannot carry on the company the continued management comes. That is, in the change center of the management paradigm, there is the environment management. Nearly, the greenhouse gas which the publication industry is the environmental toxic material like all industries is generated. The greenhouse gas is ejected in the process of running the manufacturing process and print shop of the various kinds material used as the raw material of the book. Particularly, the tree felling for getting the material of the paper is known to reach the direct influence on the global warming. This study does according to an object it considers and organizes the environment parameter based on this kind of fact as to the publication industry. And it is determined as the reference which is used as the basic materials preparing the case that carbon exhaust right transaction(CAP and TRADE) drawing are enforced in all industries and is sustainable the management of the publication industry and reduces the environmental risk among the company many risk management elements and plans and enforces the publication related policy that there is a value. In the printing publication industry, this study tried to inquire into elements discharging the environmental pollutant or the greenhouse gas. Additionally, in the printed publication production process, it tried to inquire into the effort for an environment-friendly and necessity at the printing paper and the printers ink, regarded as the element discharging the greenhouse gas all kinds of the printing materials, operation of the print shop and all kinds of the machines and recycle process, and etc. These considerations make these industrial field employees aware of the significance about a conservation and environmental protection. They try to give a help in the subsequent study producing quantitatively each environmental parameter emission of green house gas. This makes the calculation of the relative $CO_2$ output reproached ultimately possible. Meanwhile, in a sense, many research protects and improving an environment in connection with the contents of research at the printing publication industrial field is in progress. There will be the voluntary human face that it has to protect an environment but this can not do by the outside factor according to all kinds of environment related law and regulation. Anyway, because of acting on company management as the factor of oppression, the increase of this environment-related correspondence cost could know that the research that the environment loading relates with a procurement and development, environment management system introduction, quality control standard, including, normalizing including a material, and etc. through the part of the effort to reduce the cost low was actively in progress. As to the green growth era, as follows, this paper prescribed the subject and alternative of the print publication industry. It is surrounded by the firstly new digital environment and the generation of the subject. And secondly the printing industry is caused by the point of time when the green growth leaves by the topic which is largest in the global industry and it increases. The printing publication industry has to prepare the bridgehead for the environment-friendly green growth as the alternative for this resolution with first. The support blown in each industry becomes the obligation not being selection. Prestek in which the print publishing was exposed to spend many energies and which is known as the practice of the sustainable print publishing insisted that it mentioned importance of the green printing through the white pages in 2008 and a company had to be the green growth comprised through the environment-friendly activity. The core management for the sustainable printing publication industry presented from Presstack white pages is compacted to 4 words that it is a remove, reduce, recover, and recycle. Second, positively the digital printing(POD) system should be utilized. In the worldwide print out market, the digital printing area stops at the level of 10% or so but the change over and growth of the market of an analog-to-digital will increase rapidly in the future. As to the CEO Jeff Hayes of the Infoland, the offset print referred to that it of the traditional method got old and infirm with the minor phase of the new printing application like the customer to be wanted publication and the print of the digital method led the market. In conclusion, print publishers have to grasp well the market flow in the situation where a digitalization cannot be generalized and a support cannot avoid. And it keeps pace with the flow of the digital age and the recognition about the effort for the development and environment problem have to be raised. Particularly, the active green strategy is employed for the active green strategy.

코스닥 상장 시 실패위험 결정요인과 주가반응에 관한 연구 (Determinants of IPO Failure Risk and Price Response in Kosdaq)

  • 오성배;남삼현;이화득
    • 벤처창업연구
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    • 제5권4호
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    • pp.1-34
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    • 2010
  • 우리나라 코스닥 시장은 1996년 처음 생긴 이래 상당한 양적 성장은 해왔으나 투자자의 두터운 신뢰를 받지 못하는 실정이다. 건전한 기업을 발굴하여 육성하고 코스닥 시장이 투자자들에게 신뢰를 주기 위해서는 코스닥 상장기업의 정확한 가치평가와 기업 생존 가능성 평가는 매우 중요하지만 코스닥 기업을 대상으로 실패위험을 분석한 논문은 많지 않은 실정이다. 본 연구에서는 코스닥 상장 시 기업의 실패위험 결정요인을 조사하고 이 실패위험이 주가에 반영되는지 분석하였다. 신규상장 시 실패위험 결정요인은 신규상장기업의 특성인 주관등록사와 회계감사인의 명성, 공모가와 공모규모, 기업의 나이 등을 고려하여 분석하였다. 또한 신규상장 시 실패위험이 상장 후 주가성과와 관련되는지 분석하였다. 표본은 코스닥 상장 폐지된 기업 중 인터넷 기업을 제외하고 부실과 관련된 86개 실패 기업과 실패기업과 같은 산업에 속하는 569개 건전기업을 선정하여 연구에 사용하였다. 실패위험 결정요인 분석에는 로짓모형을 이용하였다. 연구결과는 신규상장 시 실패위험 결정요인은 신규상장기업의 특성인 공모규모, 회계감사인의 명성, 기업의 나이 등이 유의한 영향을 주는 것으로 나타났다. 또한 재무레버리지는 실패위험에 유의한 영향을 주는 변수이지만 선행연구에서 유의한 변수로 지적된 기업규모나 수익성 변수는 실패위험에 유의한 영향을 주지 않는 것으로 나타나 신규상장 시 실패위험 분석에서는 신규상장기업의 특성을 반영하는 모형이 유효하다고 볼 수 있다. 신규상장시 실패위험과 상장 후 주가성과와의 관계 분석에서는 유의한 음(-)의 관련성이 나타나 비 인터넷기업의 실패위험이 주가에 반영된다고 해석할 수 있다. 코스닥 신규상장기업의 생존가능성이 낮은 편이며 정부의 각종 지원을 받는 벤처기업이 실패하는 경우 투자자들에게 극심한 손해를 끼칠 수 있고 나아가 경제에 악영향을 미칠 수 있기 때문에 본 연구의 결과는 정부의 규제당국이나 신용분석을 담당하는 실무자에게 상당한 도움이 될 것으로 생각된다.

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가와사키 병 환아에서 관상동맥 합병증의 예측인자 (Predictive indicators of coronary artery complications in Kawasaki disease)

  • 박민지;전인상;차한;조강호;정미진;최덕영
    • Clinical and Experimental Pediatrics
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    • 제52권10호
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    • pp.1161-1166
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    • 2009
  • 목 적 : 현재 소아 연령에서 가장 흔한 후천적 심질환의 원인이 되고 있는 가와사키 병은 해마다 발병률이 증가하고 있으며 합병증 발생 또한 증가될 것으로 예상된다. 따라서 가와사키 병 환아의 임상적 소견, 검사실 소견을 바탕으로 가와사키 병의 관상동맥 합병증을 예측할 수 있는 인자를 알아보고자 하였다. 방 법 : 가천의과학대학교 길병원 소아과에서 2005년 1월부터 2008년 3월까지 가와사키 병으로 진단 및 치료를 받은 환아 201명을 대상으로 관상동맥 병변이 없었던 군(group I; 150명)과 있었던 군(group II; 51명)로 나누어 임상적 소견과 검사실 소견을 비교하였고 이 때 선별된 인자들을 바탕으로 관상동맥 병변에 미치는 영향을 도출하였다. 임상적 소견으로는, 나이, 성별, 총 발열기간, IVIG 투여 후 지속된 발열기간, 발열 후 치료 시작되기까지 걸린 기간, IVIG 총 투여횟수, 관상동맥 병변 여부, 검사실 소견으로는, 총 백혈구 수, 중성구 수, 혈색소, 적혈구 용적, 혈소판 수, 혈구침강속도, CRP, 알부민, 총 콜레스테롤, 중성지방 등의 수치가 사용되었다. 결 과 : 두 집단 간의 비교분석에서는, 2군(group II) 이 총 발열기간(P<0.05), IVIG 투여 후 지속된 발열기간(P<0.05), 발열 후 IVIG 치료 시작되기까지 걸린 기간(P<0.05)에서 1군(group I)보다 유의하게 길었다. 치료기간 동안 IVIG 투여 횟수는 1군(group I)이 2군(group II)보다 통계적으로 유의하게 낮은 결과를 보였다(P<0.05). 검사실 소견은 CRP 수치가 2군(group II)에서 의미 있게 높았으나 그 외의 다른 수치들은 양 군 간의 유의한 차이를 보이지 않았다. 앞서 선별된 인자들 중에서, 총 발열기간이 10일 이상일 때, IVIG 투여 후 48시간동안 열이 지속될 때, 발열 후 10일 이상 치료가 지연된 경우에, 각각 약 6배(OR=5.95, P=0.003) 5배(OR=5.11, P=0.005) 3.5배(OR=3.47, P=0.049) 관상동맥 병변 위험이 증가하였다. 또한 IVIG 초 치료보다 IVIG 재 치료(2회 이상)인 경우가 관상동맥 병변 위험이 4배(OR=4.02, P=0.001) 증가하였다. CRP는 6 mg/dL 미만인 집단에 비해 관상동맥 병변 위험이 6-9 mg/dL인 집단에서는 2배(OR=2.32, P=0.049), 9 mg/dL 이상인 집단은 3배(OR=3.18, P=0.003)로 CRP 수치의 증가에 따라 위험도가 증가하는 양상을 보였다. 그러나 위의 다섯 인자를 다변량 분석을 시행하였을 때 의미 있는 위험인자는 IVIG 재 치료(2회 이상) 경우(OR=5.29, P=0.034)와 CRP 6-9 mg/dL (OR=2.63, P=0.040), 9 mg/dL 이상(OR=2.84, P=0.014)만이 확인되었다. 결 론 : 기존 연구와 마찬가지로, 본 연구에서도 발열기간은 관상동맥 병변의 위험도와 가장 관련이 깊은 것으로 나타났으며 가와사키 병의 치료에 있어서 발열 후 IVIG의 신속한 투여로 인해 총 발열기간을 줄이려는 노력의 중요성이 확인되었다. 관상동맥 합병증의 예측인자를 선별하기 위해서는 기존의 알려진 예측인자 간의 연관성을 밝히고 객관화된 평가법의 마련을 위한 추가적인 연구가 더 필요할 것으로 사료된다.

Numerical analysis of water flow characteristics after inrushing from the tunnel floor in process of karst tunnel excavation

  • Li, S.C.;Wu, J.;Xu, Z.H.;Li, L.P.;Huang, X.;Xue, Y.G.;Wang, Z.C.
    • Geomechanics and Engineering
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    • 제10권4호
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    • pp.471-526
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    • 2016
  • In order to investigate water flow characteristics after inrushing in process of karst tunnel excavation, numerical simulations for five case studies of water inrush from the tunnel floor are carried out by using the FLUENT software on the background of Qiyueshan high risk karst tunnel. Firstly, the velocity-distance curves and pressure-distance curves are drawn by selecting a series of probing lines in a plane. Then, the variation characteristics of velocity and pressure are analyzed and the respective optimized escape routes are made. Finally, water flow characteristics after inrushing from the tunnel floor are discussed and summarized by comparing case studies under the conditions of different water-inrush positions and excavation situations. The results show that: (1) Tunnel constructors should first move to the tunnel side wall and then escape quickly when water inrush happens. (2) Tunnel constructors must not stay at the intersection area of the cross passage and tunnels when escaping. (3) When water inrush from floor happens in the left tunnel, if tunnel constructors meet the cross passage during escaping, they should pass through it rapidly, turn to the right tunnel and run to the entrance. (4) When water inrush from floor happens in the left tunnel, if there is not enough time to escape, tunnel constructors can run to the trolley and other equipment in the vicinity of the right tunnel working face. In addition, some rescuing equipment can be set up at the high location of the cross passage. (5) When water inrush from floor happens in the cross passage, tunnel constructors should move to the tunnel side wall quickly, turn to the tunnel without water inrush and run to the entrance. (6) When water inrush from floor happens in the cross passage, if there is not enough time to escape, tunnel constructors can run to the trolley and other equipment near by the left or the right tunnel working face. The results are of important practical significance and engineering value to ensure the safety of tunnel construction.

하도준설이 사행하천에 미치는 수리학적 영향 분석 (Analysis of Hydraulic Effect by River Dredging in a Meandering Channel)

  • 김태형;김병현;한건연
    • 한국지리정보학회지
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    • 제18권4호
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    • pp.14-30
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    • 2015
  • 본 논문에서는 하상퇴적이 심한 사행하천에서의 월류로 인한 침수피해와 제방 세굴 및 제방유실에 대한 피해를 저감시키기 위한 구조적 대안으로, 준설이 얻을 수 있는 수리학적 효과를 분석하고자 하였다. 사행사천 구간에서의 수리해석을 위해 2차원 수리해석 모형인 RMA-2 모형을 선정하였고, 준설 전의 현재 단면과 준설 후의 가정 단면을 GIS tool을 이용하여 구현한 후 2차원 유한요소격자를 구성하여 모형을 구동하였다. 준설 전 후에 대해 계산된 수위, 수심, 유속, 그리고 소류력을 현재의 계획홍수위와 비교하였고, 편수위가 발생한 지점에서 최대홍수위를 비교 분석한 결과 계획홍수위 대비 최대 0.58m의 수위저감 효과를 나타내었다. 분석구간 내에 위치한 제방에서의 소류력은 전 구간에 대해 평균 42~67% 가량 감소됨을 확인할 수 있었다. 이와 같은 결과를 통해 하천 사행구간에 위치한 유수의 흐름을 방해하는 하상퇴적물의 준설이 만곡부에 위치한 제방에서의 월류 및 세굴에 대한 위험도를 저감시키고 주변 농경지의 침수피해를 경감시킬 수 있는 적절한 구조적 대책이 될 수 있음을 확인할 수 있었다.

급식장의 조리기구.용기 및 작업환경에 대한 미생물학적 위해분석 (Evaluation of Microbiological Hazards of Cooking Utensils and Environment of Mass Catering Establishments)

  • 박희경;김경립;신혜원;계승희;유화춘
    • 한국식품위생안전성학회지
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    • 제15권4호
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    • pp.315-323
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    • 2000
  • 국내 단체급식업체의 급식장 위생환경에 대한 기초 정보를 제공하고 단체급식에 적용할 수 있는 HACCP Plan개발시 급식장에서의 위해요소중 조리기구 및 용기, 조리종사자, 급식 작업장 등의 위해요소에 대한 정보를 제공하기 위하여 미생물학적인 분석이 실시되었다. 도마의 위생상태는 육류, 야채 및 생선용의 도마종류별 및 급식장별 차이가 있었으나 일반적으로 일반세균수가 검체 채취면적 10$\times$10 $ extrm{cm}^2$$10^2$~$10^4$ CFU 정도로 양호하였으며, 소독한 행주의 경우 일반세균은 상당히 낮았고 대장균균은 검출되지 않아 양호하였다. 반면 채와 탈피기 등의 조리기구는 기구별, 급식장별 및 분석횟수별로 차이는 있으나 일반세균이 $10^{6}$ CFU이상 검출되거나 대장균군도 $10^{6}$ CFU이상 검출된 곳도 있어 전반적으로 위생상태가 좋지 않았으며, 특히 칼의 경우 오염된 소독용액에 의한 이차오염이 문제되었다. 이러한 오염된 전처리기구는 원부재료를 전처리할 때 교차 오염시킬 수 있어 항상 세심한 주의와 관리.운영이 필요할 것으로 보인다. 조리종사자의 손에 대한 분석 결과 1차에서 $10^4$ CFU 이하의 일반세균 및 대장균관이 일부에서 검출되었으나 2차 및 3차 측정시 점차 줄어드는 경향을 보였으며 황색포도상구균은 전혀 검출되지 않았다. 급식환경의 위생관리실태를 파악하기 위한 공중낙하균을 측정한 결과 작업장의 경우 일반세균수는 모든 급식장에서 7 CFU/Plate 이하로 검출되었고 공중낙하 황색포도상구균은 단 1곳의 측정지점에서만 검출되었다.

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유해 무기질의 자연정화 : 지화학적 고찰 (NATURAL ATTENUATION OF HAZARDOUS INORGANIC COMPONENTS: GEOCHEMISTRY PROSPECTIVE)

  • Lee, Suk-Young;Lee, Chae-Young;Yun, Jun-Ki
    • 대한자원환경지질학회:학술대회논문집
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    • 대한자원환경지질학회 2002년도 제18차 공동학술강연회 자연저감고 지질학 (대한 자원 환경지질학회)
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    • pp.81-100
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    • 2002
  • While most of regulatory communities in abroad recognize ' 'natural attenuation " to include degradation, dispersion, dilution, sorption (including precipitation and transformation), and volatilization as governing Processes, regulators prefer "degradation" because this mechanism destroys the contaminant of concern. Unfortunately, true degradation only applies to organic contaminants and short- lived radionuclides, and leaves most metals and long-lived radionuclides. The natural attenuation Processes may reduce the potential risk Posed by site contaminants in three ways: (i)contaminants could be converted to a less toxic form througy destructive processes such as biodegradation or abiotic transformations; (ii) potential exposure levels may be reduced by lowering concentrations (dilution and dispersion); and (iii) contaminant mobility and bioavailability may be reduced by sorption to geomedia. In this review, authors will focus will focul on "sorption" among the natural attenuation processes of hazardous inorganic contaminants including radionuclides. Note though that sorption and transformation processes of inorganic contaminants in the natural setting could be influenced by biotic activities but our discussion would limit only to geochemical reactions involved in the natural attenuation. All of the geochemical reactions have been studied in-depth by numerous researchers for many years to understand "retardation" process of contaminants in the geomedia. The most common approach for estimating retardation is the determination of distrubution coefficiendts ($K_{d}$) of contaminants using parametric or mechanistic models. As typocally used in fate and contaminant transport calculations such as predictive models of the natural attenuation, the $K_{d}$ is defined as the ratio of the contaminant concentration in the surrounding aqueous solution when the system is at equilibrium. Unfortunately, generic or default $K_{d}$ values can result in significant error when used to predict contaminant migration rate and to select a site remediation alternative. Thus, to input the best $K_{d}$ value in the contaminant transport model, it is essential that important geochemical processes affecting the transport should be identified and understood. Precipitation/dissolution and adsorption/desorption are considered the most important geochemical processes affecting the interaction of inorganic and radionuclide contaminants with geomedia at the near and far field, respectively. Most of contaminants to be discussed in this presentation are relatively immobile, i.e., have very high $K_{d}$ values under natural geochemical environments. Unfortunately, the obvious containment in a source area may not be good enough to qualify as monitored natural attenuation site unless owner demonstrate the efficacy if institutional controls that were put in place to protect potential receptors. In this view, natural attenuation as a remedial alternative for some of sites contaminated by hazardous-inorganic components is regulatory and public acceptance issues rather than scientific issue.

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Expression of Hepatitis B Virus S Gene in Pichia pastoris and Application of the Product for Detection of Anti-HBs Antibody

  • Hu, Bo;Liang, Minjian;Hong, Guoqiang;Li, Zhaoxia;Zhu, Zhenyu;Li, Lin
    • BMB Reports
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    • 제38권6호
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    • pp.683-689
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    • 2005
  • Antibody to hepatitis B surface antigen (HBsAb) is the important serological marker of the hepatitis B virus (HBV) infection. Conventionally, the hepatitis B surface antigen (HBsAg) obtained from the plasma of HBV carriers is used as the diagnostic antigen for detection of HBsAb. This blood-origin antigen has some disadvantages involved in high cost, over-elaborate preparation, risk of infection, et al. In an attempt to explore the suitable recombinant HBsAg for the diagnostic purpose, the HBV S gene was expressed in Pichia pastoris and the product was applied for detection of HBsAb. Hepatitis B virus S gene was inserted into the yeast vector and the expressed product was analyzed by sodium dodecyl sulphate polyacrolamide gel electrophoresis (SDS-PAGE), immunoblot, electronic microscope and enzyme linked immunosorbent assay (ELISA). The preparations of synthesized S protein were applied to detect HBsAb by sandwich ELISA. The S gene encoding the 226 amino acid of HBsAg carrying ahexa-histidine tag at C terminus was successfully expressed in Pichia pastoris. The His-Tagged S protein in this strain was expressed at a level of about 14.5% of total cell protein. Immunoblot showed the recombinant HBsAg recognized by monoclonal HBsAb and there was no cross reaction between all proteins from the host and normal sera. HBsAb detection indicated that the sensitivity reached 10 mIu (micro international unit)/ml and the specificity was 100% with HBsAb standard of National Center for Clinical Laboratories. A total of 293 random sera were assayed using recombinant S protein and a commercial HBsAb ELISA kit (produced by blood-origin HBsAg), 35 HBsAb positive sera and 258 HBsAb negative sera were examined. The same results were obtained with two different reagents and there was no significant difference in the value of S/CO between the two reagents. The recombinant HBV S protein with good immunoreactivity and specificity was successfully expressed in Pichia pastoris. The reagent for HBsAb detection prepared by Pichia pastoris-derived S protein showed high sensitivity and specificity for detection of HBsAb standard. And a good correlation was obtained between the reagent produced by recombinant S protein and commercial kit produced by blood-origin HBsAg in random samples.

한 콘돔공장근로자들의 수근관증후군에 관한 연구 (Carpal Tunnel Syndrome among workers in a condom industry)

  • 강중구;백도명;이윤정;마효일;손미아;이홍기;최정근
    • Journal of Preventive Medicine and Public Health
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    • 제29권3호
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    • pp.507-519
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    • 1996
  • The objectives of this study are to investigate the prevalence of occupation related carpal tunnel syndrome(CTS) among workers in a condom industry : to analyse the sensitivity and specificity of clinical signs or symptoms such as hand diagram, Tinel's sign and Phalen's sign in carpal tunnel syndrome : and to test vibration threshold test using audiometry as a technically easy and noninvasive method in the diagnosis of carpal tunnel syndrome in stead of nerve conduction velocity (NCV). The study group was divided into exposed group(39 cases) and non-exposed group(48 cases) based on whether or not excessive use of wrist movements exsist. 1. There are stastically significant differences in symptoms and signs of carpal tunnel syndrome such as hand diagram, Tinel's sign and Phalen's sign between exposed and non-exposed group(p<0.05). 2. Six cases(9 hands) were comfirmed as carpal tunnel syndrome by NCV. Five cases(7 hands) belonged to exposed group, 1 case(2 hands) to nonexposed group. As there are significant differences in prevalence of carpal tunnel syndrome between two groups(p<0.05), excessive use of wrist in occupation is a risk factor of carpal tunnel syndrome. 3. When we use NCV as a gold standard in the diagnosis of carpal tunnel syndrome, sensitivity and specificity of hand diagram, Tinel's sign and Phalen's sign is as followed; hand diagram , sensitivity 88.9%, specificity 84.2% Tinel's sign ; sensitivity 55.6%, specificity 72.8% Phalen's sign ; sensitivity 14.3%, specificity 88.4%. Among above clinical signs and symptoms, hand diagram is the best clinical screening test. 4. The differences of vibration threshold between median and ulnar nerve at the same time are useful in the diagnosis of carpal tunnel syndrome but the time change of vibration threshold of median nerve over time are not sensitive enough. It is concluded that vibration threshold between median and ulnar nerve at the same time can be used as a supplementary or alternative criterion to indicate that the nerve dysfunction is located in the carpal tunnel.

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치위생과 학생들의 B형 간염 바이러스의 표지자와 인지도에 관한 연구 (A Study on occurrence rates from serologic marker of hepatitis B virus and on perception in dental hygiene students)

  • 강은주;신상희;장선희
    • 한국학교보건학회지
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    • 제15권2호
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    • pp.183-191
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    • 2002
  • This study is aimed at offering basic data about prevention of Hepatitis B virus and infection control to dental hygiene students who will work mostly at dental offices which are characteristically exposed to a high risk of HBV infection. For this study, surveyed were 188 sophomores and juniors of the dental hygiene department who volunteered to undergo the tests of HBsAg and HBsAb. The examination of the blood collected from the samples and analysis of their perception about hygiene resulted in following conclusion: Positive HBsAg Four was found in 4 testees(2.1%) while 118(62.8%) revealed positive HBsAb. Juniors showed higher positive rate in HBsAg whereas sophomores had higher positive rate in HBsAb. But such difference has statistically no significance. Generally, students seemed to pay little attention to HBV, judging from the survey of their perception about the present state of HBsAg and HBsAb(p>0.05), conduct of infection(p<0.05), completion of 3 requested vaccinations(p>0.05), and formation of antibody(p>0.05). With regard to the infection routes of HBV, most students(92.4%) replied "through blood", which is statistically insignificant, though. Next ratio goes to the reply "through contaminated injectors". This reply came more from sophomores than from juniors, a difference which is statistically significant(p<0.05). The lowest rate of possible infection(29.2%) was thought to be "through breast-feeding of a positive mother"(p<0.05). In general, it turned out that sophomores had more knowledge about the infection routes of HBV than juniors. In terms of clinical history among family members, 6(3.1%) reported that some of their family members are currently suffering from a liver complaint, 3(1.6%) replied their family members were once afflicted, and 4(2.1%) said their members died of hepatitis. Except 10(4.7%), all the surveyees replied that their states of health are better than normal. Generally, sophomores are healthier than juniors except for the very health case, a difference which is statistically of no value.