• Safety and Health at Work
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• 제13권2호
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• pp.148-154
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• 2022

Background: Bus driving is a mentally demanding activity that requires prolonged attention to ensure safety. The aim of the study was to assess mental fatigue caused by driving a public bus and to find a profile of workers at higher risk. Methods: We evaluated changes of critical flicker fusion (CFF) (index of central arousal) and heart rate variability (HRV) (index of autonomic balance) in a 6-hour driving shift on a real route, in 31 professional bus drivers, and we tested the influence of personal factors such as sleep quality, BMI, and age. Paired t-test was used to test differences of CFF and HRV between both initial and final phase of driving, while multiple linear regression tested the influence of personal variables on the indexes of mental fatigue. Results: Results showed that CFF significantly decreased after 6 hours of bus driving (41.91 Hz, sd 3.31 vs. 41.15 Hz, sd 3.15; p = 0.041), and heart rate significantly decreased in the final phase of driving, with respect to the initial phase (85 vs. 78 bpm, p = 0.027). Increasing age (beta = -0.729, p = 0.022), risk of obstructive sleep apnea syndrome (beta = -0.530, p = 0.04), and diurnal sleepiness (beta = -0.406, p = 0.017) showed a significant effect on influencing mental fatigue. Conclusion: Elderly drivers at higher risk of sleep disorders are more prone to mental fatigue, when exposed to driving activity. Monitoring indexes of central arousal and autonomic balance, coupled with the use of structured questionnaires can represent a useful strategy to detect profile of workers at higher risk of mental fatigue in such duty.

• 대한토목학회논문집
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• 제34권2호
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• pp.667-676
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• 2014

본 연구는 제주특별자치도 내 실적공사비가 적용된 도로현장을 중심으로 물가변동에 따른 실적공사비 등락률 산정의 문제점을 분석하기 위하여 실시되었다. 본 연구를 위하여 제주특별자치도 내 9개 도로공사 현장을 중심으로 실적공사비방식, 표준품셈방식, 건설공사비지수방식에 따른 등락률을 비교 분석하였다. 분석결과 9개 현장 중 약 56%인 5개 현장에서 실적공사비의 지수조정률이 표준품셈과 건설공사비지수의 지수조정률에 비해 낮게 산정되었다. 이는 실적공사비가 적용됨에 따라 물가변동으로 인한 계약금액 조정 성립요건이 지연되고 있다는 것을 알 수 있으며, 이에 따라 공사 준공 전 물가변동으로 인한 계약금액 조정횟수의 감소와 함께 물가변동금액 역시 차이를 보일 수 있음을 의미한다. 또한, 건설공사비지수 사례분석 결과, 도로부문에 대한 지수를 적용하여 지수조정률을 산출하였으나 지수조정률이 2.0%~9.4%까지 산정되어 이는 공사금액 및 물가변동 적용시기에 따라 상당한 영향을 미치는 문제점이 나타났다.

• 한국환경생태학회지
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• 제23권6호
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• pp.516-527
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• 2009

금강수계에서 어류상과 서식지 적합도 지수(HSI: habitat suitability indexes)를 산정하기 위하여 2007년 10월부터 2009년 3월까지 23개 지점을 선정하여 어류 채집을 실시하였다. 이를 바탕으로 어류상, 상대풍부도 및 생물다양도 등을 포함한 하천의 건강성 평가를 실시하고, 우점종에 대하여 서식지 적합도 지수를 산정하였다. 모든 지점에서 채집된 어류는 총 11과 50종 6188개체였다. 한국고유종은 감돌고기(Pseudopungtungia nigra) 및 각시붕어(Rhodeus uyekii) 등 21종(42%)이 출현하였다. 출현어종중 개체수 구성비가 가장 높은 종은 피라미(Zacco platypus)로 34.3%를 차지하였고, 다음은 참갈겨니(Z. koreanus) 10.2%, 쉬리(Coreoleuciscus splendidus) 8.4% 등의 순으로 나타났다. 대부분 지점에서 우점종으로 나타난 피라미(Z. platypus)의 서식지 적합도 지수는 수심 0.1~0.9m, 유속 0~0.9m/s 및 하상재료 실트(<0.1mm)~호박돌(100.0~300.0mm)로 나타났다. 본 조사결과 금강수계 23개 지점에서 한국고유종 및 멸종위기종이 다수 출현하는 것으로 조사되어 보존 및 보호대책이 필요하다.

• 한국실내디자인학회논문집
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• 제22권1호
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• pp.339-349
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• 2013

The primary purpose of this research was to set up the standard guidelines for the planning of interior architectural environments of the detention facilities at the Korean Police Stations. By visit-studying the actual interior environmental conditions of 5 different kinds' domestic Correcting Facilities and 5 domestic police detention facilities and 2 foreign police detention facilities, comparing them to the existing Korean correctional institutions' cell facilities, that the strengths and weaknesses had been analyzed to extract the main concepts and the planning scheme for the Standard Korean Police Detention Facilities. By reserching the National human Right Commitee's Anual Reports, three different indexes were picked out for those analysis : the Environmental control index, the Detention Service support index, the Environmental support index. These three indexes will be used as Key factors for the planning of interior architectural environments of the detention facilities at the Korean Police Stations.: (1)the Environmental control index to establish the Space Program, the Spatial Hierarchy and the horizontal & vertical Security Blocks, (2)the Detention Service support index for the central Environmental Control & Security System, the Secured Privacy for both detainees & police offices, (3)the Environmental support index for the gender-respected segregation of cell zones, the psychological & physical safety design factors, the construction standards of all rooms in a detention facility. The result of this study should be used as the guidelines for "The Standard Plans and Regulations for the Korean Police Detention Facilities" to respect fundamental human rights.

• 한국환경과학회지
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• 제24권5호
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• pp.689-697
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• 2015

Based on the survey of 4 universities in Tai' an by questionnaire survey and interviews, this study acquired and analyzed the college student users' activity type, utilization frequency, retention time, companion, preference for landscape design style, the importance of the courtyard space's environment and landscape, as well as correlations between primary attributes and activity characteristics of student users. The weight of the university teaching area's courtyard space evaluation index was obtained by Analytical Hierarchy Process. The results indicated that nearly 60% college students select to study and to rest alone as the main activity type, 80% students' utilization frequency is at least two times or more a week. In addition, the relative weight of plant landscape is the highest in the 2nd class indexes of space garden landscape, and its value is 0.113; the relative weight of cleanliness is the highest in the 3rd class indexes of space environment quality, and its value is 0.143. Therefore, it should be attached much importance to constructing the environment and landscape for studying and relaxing, and the factors of cleanliness and plant landscape etc in the further design of courtyard space are taken into full consideration.

• 한국환경복원기술학회지
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• 제2권3호
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• pp.54-63
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• 1999

Quantifications of fish farm influences on stream water quality may provide basic informations on watershed management to reduce environmental impact due to fish farm development and to conserve stream water quality in forested watershed area. In this research stream water qualities around (Mt.) Paekun area were monitored by seasons and the following results were obtained. Due to the increase of pH in effluent water from the fish farm it was believed that alkalization of stream water can be accelerated by large scale development of fish farms in the forested watershed area. Negative effects on stream water quality was also observed by indications of increase in electrical conductivity and temperature of effluent water from the fish farm. Decreases of physicochemical indexes such as the amount of dissolved oxygen, percentage of dissolved oxygen and total amount of ion in effluent water from the fish farm were also negative aspects in downstream ecology. It is recommended that water purification system as well as eco-friendly fish farm design be incorporated to large scale fish farm development plan in forested watershed area.

• 한국환경보건학회지
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• 제33권1호
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• pp.1-10
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• 2007

This study accomplished to grasp the present condition of HAPs and to examine efficiently carcinogenic and non-carcinogenic health effects through health risk assessment in new apartments from June, 2004 to May,2005. Moreover, we performed uncertainty analysis by Monte-Carlo analysis to control uncertainty of exposure factors. The major results obtained from this study were as follows. Firstly, cancer risk of formaldehyde for male was $1.67{\times}10^{-5}$ in CTE in point estimation. Cancer risk of formaldehyde was showed $2.94{\times}10^{-3}$ in RME that applied worst case used results of 95 percentile in point estimation. It exceeds $10^{-6}$ of guide line in US EPA. Moreover, cancer risks of formaldehyde for female were $3.98{\times}10^{-5}$ in CTE and $3.93{\times}10^{-3}$ RME. Secondly, every hazard index for non-carcinogenic pollutants was less than 1 of permitted standards in CTE. However, in RME of male, hazard indexes of 1,2-Dichloropropane and Toluene were 1.3 and 2.0, respectively. Hazard indexes of 1,2-Dichloropropane and Totuene for female in RME were 1.7 and 2.6, respectively.

• 환경정책연구
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• 제4권1호
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• pp.113-127
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• 2005

토지이용 강도가 높은 도시비오톱을 대상으로 조류다양성 확보를 위한 비오톱 면적지수의 활용방안에 대한 연구를 수행하였다. 이 연구의 목적은 비오톱 평가지표들사이의 상관관계를 살펴보고 조류다양성을 보호하기 위한 비오톱 평가지표를 개발하여 생태적으로 건전한 도시비오톱의 효과적인 복원방법을 계획하는 데 있다. 도시 비오톱에서 조류 다양성에 영향을 주는 평가지수의 분석을 위해서, 각각의 사이트에 대해 비오톱 면적, 곤충종수, 인접도로와의 거리, 비오톱 면적지수를 조사하였다. 결론적으로, 비오톱평가 지수들 사이의 상관관계는 다음과 같은 결과가 나타났다. 조류종수와 곤층종수 > 조류종수와 비오톱 면적지수 > 곤충종수와 비오톱 면적지수 다시말해, 조류다양성은 실질적으로 곤충종수와 비오톱 면적지수에 의해 영향을 받는다. 결과로부터 얻어진 등식은 조류종수는 6.124 $\times$ 비오톱면적지수 + 0.095 $\times$ 곤충종수 - 1.197 이다. 그러므로, 비오톱면적지수와 곤충을 위한 수직적 경관다양성이 유지된다면, 작은 면적의 비오톱이라 할지라도 도시지 역에서 조류다양성을 증진시키는 데 도움을 줄 수 있을 것이다.

• 한국안전학회지
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• 제21권6호
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• pp.55-63
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• 2006

Rapid economic growth in Korea, on the other side, has generated increase of multiple complex dangers. To take off dangers scattered in the Korean society and to conduct safe society for better life, it is needed to develop social safety index. Social safety index analyzed by time series could compare and estimate various social disasters, thus it act as the foundation to set up safety policy. The research has focused on 8 social safety indexes; natural disaster, fire, traffic accident, crime, industry accident, forest fire, collapse and explosion, and environmental pollution. To find out Korean society safety index analyzed by time series, the research analyzed changes of each safety indexes in 10 years since 1994. Looking at the changes of each indexes, traffic accident showed the most improvement overall the nation, with industrial accident and collapse and explosion rating second and third place. However, crime, fire and natural disaster get worse, and especially crime has turned worsened than any other divisions.

• 한국가구학회지
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• 제26권2호
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• pp.138-144
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• 2015

Among several thermal wood modification methods German oil heating technology was applied for color changing larch and paulowniawood specimens. They were heat treated at $200^{\circ}C$ for 3 hours in an autoclave filled with linseed oil. The CIE $L^*a^*b^*$ color indexes of the shells and cores of the oil heated specimens were measured. The color difference indexes between the oil heated and the control specimens of larch and paulowniawood were in the range of 6 and 12, which implies considerably different. The color difference indexes between the core layers of the larch and paulowniawood specimens were 4.3 and 1.7, respectively. It could be concluded that the specimens of the two species were color changed uniformly by oil heating.