• 제목/요약/키워드: Stress indicators

검색결과 240건 처리시간 0.026초

Reliability Evaluation of Resilient Safety Culture Using Fault Tree Analysis

  • Garg, Arun;Tonmoy, Fahim;Mohamed, Sherif
    • 국제학술발표논문집
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    • The 8th International Conference on Construction Engineering and Project Management
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    • pp.303-312
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    • 2020
  • Safety culture is a collection of the beliefs, perceptions and values that employees share in relation to risks within an organisation. On the other hand, a resilient safety culture (RSC) means a culture with readiness of the organisation to respond effectively under stress, bounce back from shocks and continuously learn from them. RSC helps organisations to protect their interest which can be attributed to behavioural, psychological and managerial capabilities of the organization. Quantification of the degree of resilience in an organisation's safety culture can provide insights about the strong and weak links of the organisation's overall health and safety situation by identifying potential causes of system or sub-system failure. One of the major challenges of quantification of RSC is that the attributes that determine RSC need to be measured through constructs and indicators which are complex and often interrelated. In this paper, we address this challenge by applying a fault tree analysis (FTA) technique which can help analyse complex and interrelated constructs and indicators. The fault tree model of RSC is used to evaluate resilience levels of two organisations with remote and urban locations in order to demonstrate the failure path of the weak links in the RSC model.

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인터넷 중독 중재 프로그램으로서의 인지행동요법: 생리적 관점에서의 이론적 기틀 및 활용에 대한 고찰 (Review of Cognitive Behavioral Therapy as an Intervention Program for Internet Addicts: A Theoretical Framework and Implications with Physiological Perspectives)

  • 김나현;홍승희
    • Journal of Korean Biological Nursing Science
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    • 제17권3호
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    • pp.219-227
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    • 2015
  • Purpose: This study was conducted to review physiological mechanisms of internet addiction and to construct a theoretical framework for cognitive behavioral therapy for internet addicts. Methods: We searched for relevant literature in the PubMed and RISS databases using the terms "internet addiction", "internet game addiction", "internet abuser", and "online game". Only English, full-text articles published from 2000 to 2015 were included in this review of physiological indicators of internet addiction. Finally, 12 articles were selected for review. Results: The theoretical framework developed based on the review proposes that excessive internet use itself may induce physiological stress responses with an increase of stress-related hormones and neurotransmitters. Prolonged abnormal responses of these physiological features produce negative structural and functional changes in the prefrontal cortex, which is mainly involved in cognitive and executive functions. These changes may result in decreased cognitive function. As a stressor, excessive internet use leads to transforming voluntary use into involuntary, habitual use and thus promotes the development of internet addiction. Conclusion: The proposed theoretical framework encompasses cognitive processes that may contribute to the effects of internet use-induced physiological stress on internet addiction. We believe that this framework has important implications for developing cognitive behavioral strategies for internet addicts.

Evaluation of Erythrocyte Morphometric Indices in Juvenile Red Spotted Grouper, Epinephelus akaara under Elevated Water Temperature

  • Rahman, Md Mofizur;Baek, Hea Ja
    • 한국발생생물학회지:발생과생식
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    • 제23권4호
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    • pp.345-353
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    • 2019
  • Higher thermal exposure can influence the blood cell morphology and count. Hence, based on the previous results (Rahman et al., 2019), the present study evaluated the morphometric indices of erythrocytes and their nucleus under different water temperatures (25℃, 28℃, 31℃, and 34℃) to investigate their use as an indicator of thermal stress in red spotted grouper, Epinephelus akaara. 180 healthy specimens of E. akaara were exposed to four temperature conditions (25℃ as control, 28℃, 31℃, and 34℃) for 42 days, following 2 weeks of acclimation at 25℃. Erythrocyte major axis (EL), erythrocyte minor axis (EW), nucleus major axis (NL), and nucleus minor axis (NW) were examined from the blood smears on each sampling day (i.e., 2, 7, and 42 days of thermal exposure). EL and NL were significantly decreased, whereas EW and NW were increased at higher water temperature (31℃ and 34℃). The major-minor axis proportions of erythrocytes and their nucleus (EL/EW; NL/NW) were decreased with increasing water temperature (31℃ and 34℃). The strong relationships were observed among the morphometric indices of erythrocytes and their nucleus, especially in EL vs. NL and EW vs. NW. This study reveals that elevated water temperature (31℃ and 34℃) can influence the major and minor axis morphometry of erythrocytes and their nucleus in red spotted grouper. These indices may be used as stress indicators to monitor the health status of E. akaara and probably for other fish species.

지속가능한 자연생태계 보전을 위 한 평가지표 체계구축 (Construction of System on Assessment Indicators for Conservation of Sustainable Natural Ecosystem)

  • 유주한;정성관;오정학
    • 한국환경생태학회지
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    • 제19권3호
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    • pp.287-298
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    • 2005
  • 본 연구는 지속가능한 자연생태계를 객관적이고 합리적으로 평가할 수 있는 지표군을 구축함으로써 국토 및 자연환경 보전의 기초자료 제공과 더불어 환경정책 수립이나 입안을 위한 방향제시를 위해 수행되었다. 생물적 요인, 무생물적 요인, 질적 요인, 기능적 요인 등 4개의 평가항목을 선정하였으며, 평가지표는 밀도, 총 질소량, 헤메로비등급, 재화생산등56개로 추출하였다. 평가항목과 평가지표가 신뢰계수 0.6 이상으로 확인되어 설문지 설계에는 큰 문제가 없는 것으로 나타났다. 평가지표의 상관분석 결과, 생물적 요인의 경우 군도와 우점도, 무생물적 요인의 경우 토성과 방위, 질적 요인의 경우 귀화율과자연파괴도, 기능적 요인의 경우산사태 방지와토양침식 방지가 높은상관성을 보였다. 다차원 척도법에 의해 차원결정을 수행한 결과, 스트레스값은 $0.042\sim0.133$, 적합도 지수는 0.9 이상으로 나타나 통계적 문제는 발생하지 않았다. X축의 경우 생물적 요인은 구조, 무생물적 요인은 관점, 질적 요인은 구성, 기능적 요인은 대상이고 Y축은 형태, 범위, 구조, 활동으로 형성되었다.

웨브를 볼트로 접합한 보-기둥 접합부의 유한요소해석 (FEA of Beam-Column Connection with Bolted Web)

  • 신경재;임보혁;이수헌;최성모
    • 한국강구조학회 논문집
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    • 제23권3호
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    • pp.305-316
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    • 2011
  • 건축물이 크고 높아질수록 고강도 강재의 필요성이 부각 되었고 이러한 요구에 따라 강도와 항복비가 개선된 성능을 가진 강재들이 개발되고 있다. 본 연구에서는 고강도강재를 사용한 웨트볼트 접합방식을 가지는 모멘트접합부의 거동을 ABAQUS를 사용한 유한요소해석을 통하여 파악하였다. 해석모델은 이미 수행되어진 실험체를 대상으로 하였으며 파괴시까지의 반복하중을 해석모델에 가력하였다. 유한요소해석결과 실제실험으로는 얻기 힘든 여러 가지의 반응지수들을 구하였다. 이러한 지수들은 응력과 변형에 관계한 값으로 소성회전각이 0.003rad, 0.03rad 그리고 파괴시까지 3단계에서 구하였다. 특히 파괴단계에서 일정한 값을 가지는 변형지수는 충분한 소성거동을 하는 접합부의 강재에 요구되어지는 기계적 성질로 제시하였다.

Prediction of coal and gas outburst risk at driving working face based on Bayes discriminant analysis model

  • Chen, Liang;Yu, Liang;Ou, Jianchun;Zhou, Yinbo;Fu, Jiangwei;Wang, Fei
    • Earthquakes and Structures
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    • 제18권1호
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    • pp.73-82
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    • 2020
  • With the coal mining depth increasing, both stress and gas pressure rapidly enhance, causing coal and gas outburst risk to become more complex and severe. The conventional method for prediction of coal and gas outburst adopts one prediction index and corresponding critical value to forecast and cannot reflect all the factors impacting coal and gas outburst, thus it is characteristic of false and missing forecasts and poor accuracy. For the reason, based on analyses of both the prediction indicators and the factors impacting coal and gas outburst at the test site, this work carefully selected 6 prediction indicators such as the index of gas desorption from drill cuttings Δh2, the amount of drill cuttings S, gas content W, the gas initial diffusion velocity index ΔP, the intensity of electromagnetic radiation E and its number of pulse N, constructed the Bayes discriminant analysis (BDA) index system, studied the BDA-based multi-index comprehensive model for forecast of coal and gas outburst risk, and used the established discriminant model to conduct coal and gas outburst prediction. Results showed that the BDA - based multi-index comprehensive model for prediction of coal and gas outburst has an 100% of prediction accuracy, without wrong and omitted predictions, can also accurately forecast the outburst risk even for the low indicators outburst. The prediction method set up by this study has a broad application prospect in the prediction of coal and gas outburst risk.

해양경찰 파출소 조직의 건강성과 조직효과성에 관한 연구 - 근무자의 인식을 중심으로 - (A Study on the Health and Organizational Effectiveness of Korea Coast Guard Substation organization: Focused on Recognition of Workers)

  • 김상구;박재홍
    • 한국항해항만학회지
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    • 제34권1호
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    • pp.83-89
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    • 2010
  • 본 논문은 일선파출소에 근무하는 해양경찰관들을 조사대상으로 하여 해양경찰 파출소 조직의 건강성 수준을 파악하고, 조직효과성에 영향을 미치는 조직건강성 측정지표들을 분석하고자 하였다. 연구의 결과 첫째, 해양경찰 파출소 조직의 건강성 수준은 업무스트레스를 제외한 모든 측정지표들에서 평균 이상인 것으로 나타나, 조직건강성 수준은 양호한 것으로 판단되었다. 둘째, 조직효과성에 의미있는 영향을 미치는 조직건강성 측정지표들은 개발문화, 보수, 동료관계, 승진제도, 감독, 직무자율성, 직무자체, 조직신뢰감, 업무지향성 등으로 나타났다. 특히 보수, 동료관계, 직무자율성, 직무자체, 조직신뢰감, 업무지향성 등의 측정지표들은 조직효과성에 긍정적인 영향을 미치는 것으로 나타났고, 현행 해양경찰조직의 개발문화, 승진제도, 감독 등은 일선파출소에 근무하는 해양경찰관의 조직효과성에 부정적인 영향을 미치는 것으로 나타났다.

실내종 Chironomus riparious와 야외종 Chironomus plumosus의 중금속 노출에 따른 분자지표 유전자 발현 (The Molecular Biomarker Genes Expressions of Rearing Species Chironomus riparious and Field Species Chironomus plumosus Exposure to Heavy Metals)

  • 김원석;김로사;박기연;차밀라니;곽인실
    • 생태와환경
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    • 제48권2호
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    • pp.86-94
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    • 2015
  • Chironomous is aquatic insect belonging to order Diptera, family Chironomidae. Their larval stage can be found mainly in aquatic benthic environment, hence good model organism to study environmental toxicology assessments and consider as useful bio indicators of contamination of the aquatic environment. In this study, Chironomus Heat Shock Proteins, Cytochrome 450, Glutathione S-transferase, Serine-type endopeptidase gene expressions were compared between polluted field areas (Chironomus plumosus) and under laboratory conditions (Chironomus riparious) to investigate molecular indicators for environmental contaminant stress assessment. Heavy metal (Al, Fe, Mn, Cu, Cr, Zn, Se, Pb, As, Cd) concentrations in sediments collected from three study areas exceeded the reference values. Moreover, HSPs, CYP450 and GST gene expression except SP for C. plumosus showed higher expression than C. riparious gene expression. Similar gene expression pattern was observed in C. riparious that exposed environment waters up to 96 h when compared to C. plumosus exposed to waters that grown in lab conditions. In summary, this comparative gene expression analysis in Chironomous between field and laboratory condition gave useful information to select candidate molecular indicators in heavy metal contaminations in the environment.

Oxidative stress status and reproductive performance of sows during gestation and lactation under different thermal environments

  • Zhao, Yan;Kim, Sung Woo
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권5호
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    • pp.722-731
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    • 2020
  • Objective: Two experiments were conducted using 28 healthy multiparous sows to evaluate the oxidative stress status and reproductive performance of sows during gestation and lactation under different thermal environments. Methods: Fourteen multiparous sows were used in Exp. 1 under a high thermal environment, and the other 14 multiparous sows were used in Exp. 2 under a moderate thermal environment. In both experiments, reproductive performances of sows were recorded. Plasma samples were collected on d 35, 60, 90, and 109 of gestation, and d 1 and 18 of lactation for malondialdehyde, protein carbonyls, 8-hydroxy-deoxyguanosine, immunoglobulin g (IgG), and IgM analysis. Results: For sows in Exp. 1, plasma malondialdehyde concentration on d 109 of gestation tended to be greater (p<0.05) than it on d 18 of lactation. Plasma concentration of protein carbonyl on d 109 of gestation was the greatest (p<0.05) compared with all the other days. Plasma concentrations of 8-hydroxy-deoxyguanosine on d 109 of gestation was greater (p<0.05) than d 18 of lactation in Exp. 1. For sows in Exp. 2, there was no difference of malondialdehyde and protein carbonyl concentration during gestation and lactation. In both Exp. 1 and 2, litter size and litter weight were found to be negatively correlated with oxidative stress indicators. Conclusion: Sows under a high thermal environment had increased oxidative stress during late gestation indicating that increased oxidative damage to lipid, protein, and DNA could be one of the contributing factors for reduced reproductive performance of sows in this environment. This study indicates the importance of providing a moderate thermal environment to gestating and lactating sows to minimize the increase of oxidative stress during late gestation which can impair reproductive outcomes.

해일유발지진의 응력강하 특성 (Stress Drop Characteristics of the Tsunami Generating Earthquake)

  • 오석훈;윤용훈;양준모;김수경;이덕기
    • 한국지구과학회지
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    • 제24권8호
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    • pp.704-710
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    • 2003
  • 해일지진 및 해일유발지진의 특성을 기존의 연구결과인 규모, 모멘트, 에너지 그리고 단층의 길이 등의 자료를 이용하여 응력강하량 및 지체구조 관점에서 분석을 하였다. 해일지진(Tsunami Earthquake)은 일반 지진이나 해일유발지진(Tsunamigenic Earthquake)보다는 약 10bar 정도의 매우 낮은 응력강하량을 가지며 에너지/모멘트 비가 매우 작으며 주로 해구의 매우 낮은 경사의 스러스트 단층에서 발생하는 것으로 분석이 된다. 한편 동해에서 해일을 유발한 지진들은 약30${\sim}$50bar의 응력강하량로서 에너지/모멘트비가 세계평균과 비슷한 스러스트 단층에서 발생하는 것으로 유추된다. 따라서 응력강하, 에너지/모멘트 비, 그리고 스러스트 단층의 경사각은 지진해일 발생특성을 나타내는 인자로 대표될 수 있다.