Distribution of airborne bacteria in the entire regions of South Korea was investigated and analyzed by region and type of multi-use facilities. At first, 10 public facilities were selected including general restaurant, retail store, public transport, retail market, apartment house, underground parking lot, financial institution, business facility, educational institution, and public toilet, which are located at the regions such as Seoul, Busan, Daejeon, Gwangju, Gyeonggi, Jeju, and Gangwon. The regional distribution of the floating bacteria was identified that Micrococcus sp. was highly prevalent in Seoul (21.5 percent). In Daejeon, Bacillus sp. was highly prevalent (12.4 percent). In Busan, Micrococcus sp. was highly prevalent (22.8 percent). In Gwangju, Bacillus sp. was 9.35%. In Gyeonggi, Micrococcus sp. was 13.7%, and in Gwangju and Jeju, Micrococcus sp. was 11.2 percent and 92%. All in all, Micrococcus sp. and Bacillus sp. were highly detected throughout the entire region and multi-use facilities. Next, whether or not these airborne bacteria could influence the health of people was examined using HaCat human skin cell line which is human epithermal Karatinocytes related to allergic dermatitis. Among these isolated microorganisms, the HaCat cell proliferation was decreased by Arthrobacter sp., Bacillus sp., Brachybacterium sp., Brevundimonas sp., Kocuria sp., Mammaliicoccus sp., Norcardia sp., Prestia sp., Phychrobacillus sp., and Rhodococcus sp., while it was affected by the other bacteria. Therefore, these results have suggested that the airborne floating bacteria could be considered as the marker for the environmental risk management against atopic dermatitis, and it is needed for controlling the bacteria number that suppressed the proliferation of HaCat cells.

The aim of this study is to consider the effect hydrogen on dezincification behavior of Cu-Zn alloys. The investigations include microstructural observations with scanning electron microscope and chemical composition analysis with energy dispersive spectrometer. The dezincification layer was found to occur in high pressure hydrogen atmosphere, not in air atmosphere. In addition, the layers penetrated into the inner side along the grain boundaries in the case of hydrogen condition. The shape of the dezincification layers was porous because of Zn dissolution from the α or β phase. In the case of stress corrosion cracks formed in the Cu-Zn microstructure, the dezincification phenomenon with porous voids was also accompanied by grain boundary cracking.

The purpose of this study is to detect metabolic syndrome components related to exposure of organic solventthrough comparison and analysis of metabolic syndrome components between workers at the workplace exposedto organic solvent (toluene, xylene, styrene) and workers at general workplace. During the period from Januaryto December 2010, the survey was conducted against male workers of 168,769 persons with age group 30-59completed medical checkup, dividing workers at organic solvent exposed work place and workers of generalworkplace against which comparisons were carried out about the result of general characteristics, blood test.Whether exposed to organic solvent and exposed period relationship with metabolic syndrome components wereidentified through execution of multiple logistic regression analysis. The prevalence rate of the metabolic syndromeby age was 15.0% for the 30s, 19.8% for the 40s, 22.9% for the 50s. For the whole workers, the prevalence rateof the metabolic syndrome was 17.4% in exposed workplace and 18.4% in general workplace that was higherthan the rate in exposed workplace. Even if age, drinking, smoking, exercise, region and BMI were corrected,the exposure to the organic solvent was the higher the significance of blood pressure and fasting glucose werestatistically and also the longer the period of exposure was, the higher the significance of blood pressure wasstatistically. In this study, the exposure to the organic solvent showed a statistically significant relevance with bloodpressure and fasting glucose among the metabolic syndrome components and the period of exposure showed astatistically significant relevance with blood pressure. Further researches should be conducted by prospective cohortstudy about the organic solvent and the metabolic syndrome components supplementing the defects.

This study examined the associations between job stress and psychosocial stress in telecommunication service workers. In this survey, four hundred seventy workers and six variables(general characteristics, state of health, job characteristics, personality, psychosocial characteristics, and job stress) were used to measure worker's subjective satisfaction and status of stress. The results of this study indicated that 135 workers(28%) were classified into a high risk group to stress, 317 workers(67%) were into a potential risk group, and only 18 workers(6%) were into a healthy group. Also the results indicated that job stress outcomes related to job characteristics, personality, and psychosocial characteristics.

본 연구는 하상재료의 종류와 유속에 따른 세굴변화에 대한 연구를 진행하였고, 유속, 구성방법 및 재료와 세굴에 대한 상관관계를 정의하여 호안 및 제방의 운용성을 검토하고자 실험을 통한 연구를 진행하였다. 본 연구의 실험에 사용된 재료는 제방에 사용되고 있는 재료로 모래, 황토를 이용 하였다. 실험실규모 고속수로에서 다양한 계측장비들을 이용하여 유속의 변화에 따른 재료의 세굴을 측정하였다. 이를 통해 세굴 전·후의 재료변 화를 수치적으로 분석하였다. 고유속흐름에서 하상재료에 따라 세굴의 정도를 비교·평가하여 안정성에 대한 연구도 진행하였다. 실험 결과 모래의 경우 응집력이 매우 약하여 1.0 m/s 이하에서도 40% 이상의 재료가 유실이 되고 황토의 경우 모래보다 유속이 빠른 2 m/s 이상에서도 6% 이하 의 재료가 유실이 되었다. 재료가 유실된 이유중 하나는 강한 응집력으로 건조균열이 발생하여 세굴에 취약한 결과를 보였다. 본 연구에서는 이러한 건조균열의 발생부터 재료가 유실되는 현상을 제거하는 방법부터 재료에 대한 구성과 유실정도를 평가 하였다.