• 한국생활과학회지
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• 제19권4호
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• pp.745-760
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• 2010

The purposes of this study were to investigate the state of indoor thermal and air environment during winter in the one-room type multi-family houses occupied by university students and to analyze factors which influenced this environment. Field survey was conducted in 10 houses between 30th January, 2009 and 13th February, 2009 which measured indoor thermal and air elements as well kept records of interviews with residents and other related factors. Measured elements were air temperature, relative humidity, as well as concentrations of $CO_2$, CO, TVOC, and PM-10. The results can be summarized as follows. 1) The mean air temperature in each house ranged from 19.3 to $25.3^{\circ}C$, so most houses were not suitable for evaluation criteria($20-22^{\circ}C$). The average $CO_2$ concentration in each house was 965~3259ppm, so most houses exceeded evaluation criteria(1000ppm). The average TVOC concentration in each house were 0.00~1.17ppm, 5 houses exceeded evaluation criteria(0.12ppm). 2) Relative humidity, CO concentration, and PM-10 concentration were suitable for evaluation criteria. Therefore, indoor thermal and air environment during winter in one-room type multi-family housing occupied by university students was found to be generally uncomfortable. Important factor which were found to influence air temperature and the concentration of $CO_2$ were smaller space capacity than general house. Other factors which were found to influence the environment of these houses were the existence of a balcony as well as factors relating to the behavior of occupants such whether or not heating were operated, whether windows were opened, whether fans used, whether occupants smoked or used cosmetics, and whether the space was dusted.

• 대한인간공학회지
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• 제29권3호
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• pp.347-356
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• 2010

The purpose of this study is to analyze the spine stability by comparing muscle activation in various scaffold working conditions. The independent working conditions were designed by two levels of working height, existence and absence of safety handrail, and the two levels of expertise. The corresponding activities of the agonist and antagonist muscles of spine were simultaneously recorded by using EMG. As results, novice worker showed increased muscle activity while doing the task on the 2nd floor, absence of handrail. And expert showed the increase of co-contraction while working on the 2nd floor without handrail. Such co-contraction was found to increase the spine stability when the working condition become risky. On the other hand, the co-contraction was prolonged, the spine muscle fatique and disc pressure could be increased, which would increase the risk of musculo-skeletal disorder. The results of co-contraction in this study indicates that the motor control system responds to maintain the stability of the spine particularly when workers cognitively recognize the danger of falling or imbalance. This study also quantitatively accounted for the biomechanical cause of LBP among workers who has to prevent themselves from falling. Therefore, if can be said that safe environment preventing falling can also prevent workers from MSDs as well. Such knowledge can be applied to design ergonomic workplace environment as well as movable scaffold.

• Journal of Preventive Medicine and Public Health
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• 제41권1호
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• pp.1-9
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• 2008

Objectives : This study evaluated knowledge structure and its effect factor by analysis of co-author and keyword networks in Korea's preventive medicine sector. Methods : The data was extracted from 873 papers listed in the Journal of Preventive Medicine and Public Health, and was transformed into a co-author and keyword matrix where the existence of a 'link' was judged by impact factors calculated by the weight value of the role and rate of author participation. Research achievement was dependent upon the author's status and networking index, as analyzed by neighborhood degree, multidimensional scaling, correspondence analysis, and multiple regression. Results : Co-author networks developed as randomness network in the center of a few high-productivity researchers. In particular, closeness centrality was more developed than degree centrality. Also, power law distribution was discovered in impact factor and research productivity by college affiliation. In multiple regression, the effect of the author's role was significant in both the impact factor calculated by the participatory rate and the number of listed articles. However, the number of listed articles varied by sex. Conclusions : This study shows that the small world phenomenon exists in co-author and keyword networks in a journal, as in citation networks. However, the differentiation of knowledge structure in the field of preventive medicine was relatively restricted by specialization.

• 셀메드
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• 제11권3호
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• pp.16.1-16.7
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• 2021

Cancer is an abnormal growth of cells in body which leads to death. These cells are born due to imbalance in cell proliferation mechanism. In 2018, WHO released new statistics on cancer incidence, mortality, and prevalence worldwide i.e., GLOBOCAN 2018 estimates for 28 types of cancer in which more prevalence of cervix and breast cancer. According to survey, in India about 7.8 million cancer deaths and 11.5 million new cases arise in 2018, which will increase to 19.3 million new cases per year by 2025. Though breast cancer as such is not explained anywhere in Ayurvedic compendia, correlations can be done with the Stana Arbuda. Ayurveda, the ancient system of medicine came into existence 1000's of years ago with an objective of maintaining the health of people and treating diseases. Many herbs used in Ayurveda have been screened for activity against cancer and in-vitro and in-vivo studies have given promising leads. The plant, called as "Mother of Medicine", Haritaki has been extensively studied for its various ailments because of its extraordinary healing potency. Haritaki (Terminalia chebula Retz.), Family: Combretaceae have a great therapeutic value and is widely distributed in India. Dried fruit of Terminalia chebula contains high quantities phenolic compounds consist of ellagic acid, gallic acid and chebulic acid. The fruit extract of T. chebula is having different biological properties like anticancer, antioxidant, hepatic and renal protective activities etc. In this study, we focus on the use of CO₂ extract of Terminalia chebula, on the breast cancer cell line MDA-MB-231. All tests proved that CO₂ extract of Terminalia chebula containing active chemical component, therefore our experiment showed the positive results for CO₂ extract of Terminalia chebula against breast cancer cell line cancer MDA-MB-231. The MTT assay results were used to evaluate the anti-cancer activity of the extract. The percentage of cell growth and cell viability were calculated from tabulated result values of MTT assay. Cell viability MTT assay also showed significant growth inhibition, at the same time statistical analysis of MTT assay also proved significant results.

• Journal of Preventive Medicine and Public Health
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• 제55권2호
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• pp.134-143
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• 2022

Objectives: Many governments have imposed-and are still imposing-mobility restrictions to contain the coronavirus disease 2019 (COVID-19) pandemic. However, there is no consensus on whether policy-induced reductions of human mobility effectively reduce the effective reproduction number (Rt) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several studies based on country-restricted data reported conflicting trends in the change of the SARS-CoV-2 Rt following mobility restrictions. The objective of this study was to examine, at the global scale, the existence of regional specificities in the correlations between Rt and human mobility. Methods: We computed the Rt of SARS-CoV-2 using data on worldwide infection cases reported by the Johns Hopkins University, and analyzed the correlation between Rt and mobility indicators from the Google COVID-19 Community Mobility Reports in 125 countries, as well as states/regions within the United States, using the Pearson correlation test, linear modeling, and quadratic modeling. Results: The correlation analysis identified countries where Rt negatively correlated with residential mobility, as expected by policymakers, but also countries where Rt positively correlated with residential mobility and countries with more complex correlation patterns. The correlations between Rt and residential mobility were non-linear in many countries, indicating an optimal level above which increasing residential mobility is counterproductive. Conclusions: Our results indicate that, in order to effectively reduce viral circulation, mobility restriction measures must be tailored by region, considering local cultural determinants and social behaviors. We believe that our results have the potential to guide differential refinement of mobility restriction policies at a country/regional resolution.

• 한국지반공학회논문집
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• 제26권5호
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• pp.37-48
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• 2010

본 연구에서는 침투압이 주기적으로 변화하는 연근해 가물막이 시공현장에 적용하기 위해서 수두손실그래프에 의한 침투류 감시기법을 개발하였다. 이 기법에서 새로이 정의된 수두손실율은 0~1 사이의 값으로 나타나며 0이면 완전통수상태, 1이면 완전차수상태를 나타낸다. 수두손실그래프의 결정계수가 1에 가까우면 침투경로상의 지반은 안정된 상태에 있음을 나타내고 0에 가까우면 공동이 존재할 수도 있고 파이핑이 진행 중일 수도 있다. 수두손실그래프에 의한 안전관리기법은 침투상태의 변화를 민감하게 감지할 수 있도록 하며 전체 현장에 적용할 경우 각 위치별 하부지반의 침투상태를 세부적으로 판단할 수 있도록 한다.

• 한국자기학회지
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• 제14권3호
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• pp.89-94
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• 2004

본 연구에서는 InP(2${\times}$4) 재구성된 표면 위에 원자층 단위로 증착된 Co 박막의 특성을 표면 자기광 커 효과(surface magneto-optical Kerr effect, SMOKE) 시스템, 반사 고에너지 전자 회절(reflection high energy electron diffraction), 주사 터널링 현미경(scanning tunneling microscope)이 장착된 초고진공 챔버를 이용하여 조사하였다. 실시간(in situ) SMOKE 연구 결과, Co 박막이 InP(2${\times}$4) 재구성된 표면 위에 성장할 때, Co박막의 두께에 따라 자성 특성이 대조적으로 구분되는 세 가지 두께 영역이 존재함을 확인할 수 있었다. 즉, Co 박막 두께가 7 단층(monolayer, ML)보다 작은 두께 영역에서는 가로 방향(longitudinal)과 수직방향(polar) 측정에서 모두 SMOKE신호를 관찰할 수 없었다. 8$m\ell$에서 15$m\ell$까지의 Co두께 영역에서는 수평 자기 이방성과 수직 자기 이방성이 공존하는 준안정상(metastable phase)을 관찰할 수 있었다. 그리고 마지막 영역은 16$m\ell$이상의 두께를 갖는 영역으로 수평 자기 이방 강자성을 확인할 수 있었다.

• 미생물학회지
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• 제32권3호
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• pp.192-197
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• 1994

말론산을 탄소원으로 하여 성장하는 Pseudomonas fluorescens에서 60 kb 정도의 plasmid를 발견하였다. 이 plasmid를 curing한 Pseudomonas는 malonate 배지에서 자라지 못하였고 plasmid도 소실되었다. 또한 이 plasmid를 transformation과 conjugation으로 각각 E. coli와 cured P. fluorescens로 이동시킨 결과 이 plasmid를 받은 transformed E. coli와 conjugant P. fluorescens는 malonate를 탄소원으로 하여 성장하였고 malonate 대사에 관련된 효소인 malonate decarboxylase와 acetyl-CoA synthetase의 활성이 측정되었다. Western blotting을 통하여 tansformed E. coli에서 P. fluorescens와 동일한 acetyl-CoA synthetase가 malonate에 의해 induction됨을 확인하였다.

• 한국정밀공학회지
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• 제18권4호
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• pp.142-150
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• 2001

Automotive manufactures have taken more interests in tailored sheet metals for improving the rigidity, weight reduction, crash durability, and cost savings so that their application to auto-bodies has been increased. However, since the tailored sheet metals do not behave like un-welded sheet metals in press forming operations, the stamping engineers no longer rely only on conventional forming techniques. Futhermore, there is no clear understanding of the characteristics of welded metal which influence the overall press formability of tailored sheet metals. Recently, the computer simulations are prevailing for the evaluation of the formability. Unfortunately, the mechanical property of tailored sheet metal has to be quantitatively defined in the simulation. In this study, the analytical equations are formulated in order to find the mechanical properties of the welded metal in the tailored sheet metal welded by co$_2$laser. Based on force distribution assumption, the constitutive behavior of the welded metal is investigated using uniaxial tensile test results of base metals and tailored sheet metal. Then, the strength coefficient, work-hardening exponent, and plastic strain ratio of laser-welded metal are calculate from those of base metals and tailored sheet metal. In addition, the existence of weld defects in the welded metal is indirectly detected by examining the slop of strength coefficient of the welded metal.

• 보험의학회지
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• 제2권1호
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• pp.182-194
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• 1985

Cholelithiasis, one of the digestive, disease is one of the subject to have to be solved in the medical field because it is very important health problem in clinic and gives people much pain. The formulative process of gall stone is not certainly known yet, but an approach to the size, location, bile sludge of gall ston and the existence of pus is very contributive to the cure and prediction of the disease. As above, the early diagnosis of gall stone is very important. A few study on the possessing rate of gall stone in normal Korean Group is reported. But no report has submitted to the Korean Life Insurance Medical Association until now. We, the Medical Dept. of Dae Han Kyouk Life Insurance Co. Ltd., practiced ultrasonic examination for the recent 17 months and obtained 84 data of gall stone potency out of 4201 examples. We analyzed them on the basis of sex, age, gall stone incidence rate and the results are as follows; 1) The possessing rate of gall stone in female showed 1.22 times higher than in in male. 2) The older the medical examined group grow, the more the frequency of gall stone incidence increase regardless of sex. 3) Our report coincides with foreign one in sex and age, but in total gall stone incident frequency our country has 2%, which is much less than foreign one.