• Asian Pacific Journal of Cancer Prevention
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• 제16권2호
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• pp.607-611
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• 2015

Background: Chronic respiratory disease is an important factor for development of lung cancer. To explore the influence of hazy weather on respiratory diseases and its variation the present study was conducted. Materials and Methods: Data from air pollution surveillance from January to October 2014 and case records of visiting patients in the $263^{th}$ Hospital of Chinese PLA in the corresponding period were collected to analyze the relevance between different degrees of air pollution (hazy weather) and the number of visiting patients in Department of Respiratory Disease. Results: Air quality index (AQI) of hazy weather had significantly positive association with particulate matter 2.5 ($PM_{2.5}$) and the number of patients with 5 kinds of respiratory diseases i and different pollutants had distinct influences on various respiratory diseases. Conclusions: The degree of air pollution in Beijing City is in close association with the number of patients with respiratory diseases, in which $PM_{2.5}$ and $SO_2$ are in more significant influences on all respiratory diseases. This could have essential implications for lung cancer development in China.

• 보건교육건강증진학회지
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• 제13권2호
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• pp.24-34
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• 1996

This study had been carried out to analyze the relationship among the personal variables, the variales of life style and physical and mental health status of workers. In order to analyze the influence of industrial worker's life-style on physical and mental health status of workers, explore the relaionship between healh status and their life-style. Special interest in this study was the assesment of worker's physical and mental health status measured by the Todai Health Index(THI)-a self-adminstered health stutus screening instrument developed by a University of and Gumma research team. Data were collected from an industry of 1,495 workers at city of Chang Won in Korea. 1. The young age group especially the group who had short work duraion less than two years had high THI scores which were statistically significant. 2. A worker who followed 6∼7 good life style scores were found to be associated with better health status than those who followed 0-3 bad life style scores in most of all dimensions of physical and mental health scales of THI. 3. According to the multiple regression analysis, the variable of life style scores had the greatest influence on physical and mental health status of industrial workers. The variable of age, duration of work, and life style were included in the regression model(R²= 18.8).

• 대한기계학회논문집B
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• 제33권5호
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• pp.358-364
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• 2009

This paper is to investigate the influence of driving patterns of slow and high speed vehicles on the performance of continuously regenerating diesel particulate filter(DPF) system matched with operating conditions in field application. The DPF performance test for field application was carried out for two identical DPFs installed to slow and high speed vehicles. A slow speed vehicle was selected among local buses which have driving patterns to repeat running and stop frequently, while a high speed vehicle was prepared to have long route of high speed over 60km/h like inter-city buses. In this test, the regeneration performance on the DPF of slow speed vehicle deteriorated because of high soot load index(SLI) in spite of same balance point temperature(BPT) distribution for high speed vehicle. The DPF of slow speed vehicle melted in the end because the rapid increase of back pressure caused high temperature over $1200^{\circ}C$ in the ceramic wall of DPF. The PM components like ash collected to the filter in the DPF were analyzed in order to investigate the cause of the defect and provide an operation performance of DPF system. In the result of the analysis, high levels of lubrication oil ash(Ca, Mg, P, Zn) were detected.

• Journal of Welding and Joining
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• 제15권6호
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• pp.41-48
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• 1997

For analyzing the characteristics of arc welding processes, an algorithm is necessary to determine the metal transfer mode, arc stability and weld quality. In this study, the weight of spatter during welding was selected for determining the arc stability, which is very relevant to the occurrence of spatter. Weld spatter occurs mainly at the moment when the short circuit is formed and also when it is broken causing the arc to restrike. Based on this fact, the arc stability can be determined by finding the suitable parameters of welding current and arc voltage which influence the weight of spatter. Through various welding experiments, the peak current, the arcing time, the short circuit time, the current and its slope at the start of short circuit were found mainly to influence the weight of spatter. For the convenient usage, an index was proposed by combining all these parameters. It was found that the index is very effective for determining the arc stability.

• 동력기계공학회지
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• 제20권5호
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• pp.78-85
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• 2016

This paper considers the influence of internal heat exchangers to the efficiency of a refrigerating system using R170. These liquid-gas heat exchangers(internal or suction-line heat exchangers) can, in some cases, yield improved system performance while in other cases they degrade system performance. A steady state mathematical model is used to analysis the performance characteristics of refrigeration system with internal heat exchanger. The influence of operating conditions, such as the mass flowrate of R170, inner diameter tube and length of internal heat exchanger, to optimal dimensions of the heat exchanger is also analyzed in the paper. The main results were summarized as follows : the mass flowrate of R170, inner diameter tube and length of internal heat exchanger, and effectiveness have an effect on the cooling capacity, compressor work and RCI(Relative Capacity Index) of this system. Exception for the effect of inner diameter, the RCI of R170 with respect to refrigerant mass flowrate, the length and effectiveness of internal heat exchanger is about 2.1~3.3% higher than that of R13 at the same experimental conditions. With a thorough grasp of these effect, it is necessary to design the R170 compression refrigeration cycle using internal heat exchanger.

• 수산경영론집
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• 제36권1호
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• pp.51-79
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• 2005

The main propose of this study is to analyze of the Chinese Fisheries Products competitiveness in Korean Market. This study was using a model of working partnerships by James C. Anderson & James A. Narus(1990). That is, Support is found for a number of the hypothesized construct relations and in both manufacture firm and distributor firm model, for the respecification of cooperation as an antecedent rather than a consequence of trust. This study was able to apply this model's intention for the relationship between Chinese fisheries products exporter and Korean importer, because I thought that competitiveness of trade market was based on relationship between the two countries traders. The results of this study are summarized as follows. As the above result, the several hypothesized correlation among the factors were significant. These results was tried to apply the competitiveness degree index as main factors among the countries, The method of measuring competitiveness .degree index was [(outcome + influence + communication + coopration + trust + satisfaction) - conflict, In result, China was 21.5583, USA was 20.2667, East Asia was 18.79126, EU was 18.4723, Russia was 16.3858.

• Journal of Information Science Theory and Practice
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• 제3권1호
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• pp.66-76
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• 2015

This research uses a new approach to analyze the extent of influence journal papers have on the progress of varied research fields by estimation of subject-based influence on research other than impact factor that relies on citation index. It is initiated with the hypothesis that earlier established citation relations between journal and citing paper, which reveals the research field that contains the highest citation index and hence has received the greatest contribution from a particular journal, would have inconsistent contribution to the research field over the year of journal publication. The target research is primarily 128 journal papers and 4,123 citing papers from Information Systems Research published in the years 2001, 2004, 2007, and 2010. The characteristics of citation history and hallmarks of research field of citing papers were studied and analysis on significant distinction between citing fields based on the year of publication was performed. The analysis results show the order of citation rate to be highest from Computer Science (2,221 cases), Business & Economics (2,191 cases), and Information Science & Library Science (1,901 cases). The citation history of the journal, nonetheless, indicates increase in citation during 2-3 years after the earliest publication till it achieves constant citation. The statistical analysis shows significant variation in citing fields in accordance with the publication year; especially in 2010, journal contribution has increased in the fields of Business & Economics, Operations Research & Management Science, and Health Care Sciences & Services but, however, is reduced in Education & Educational Research and Social Sciences - Other Topics.

• Steel and Composite Structures
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• 제38권6호
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• pp.617-635
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• 2021

This paper numerically investigated the behavior of built-up square concrete-filled steel tubular (CFST) columns under combined preload and axial compression. The finite element (FE) models of target columns were verified in terms of failure mode, axial load-deformation curve and ultimate strength. A full-range analysis on the axial load-deformation response as well as the interaction behavior was conducted to reveal the composite mechanism. The parametric study was performed to investigate the influences of material strengths and geometric sizes. Subsequently, influence of construction preload on the full-range behavior and confinement effect was investigated. Numerical results indicate that the axial load-deformation curve can be divided into four working stages where the contact pressure of curling rib arc gradually disappears as the steel tube buckles; increasing width-to-thickness (B/t) ratio can enhance the strength enhancement index (e.g., an increment of 1.88% from B/t=40 to B/t=100), though ultimate strength and ductility are decreased; stiffener length and lip inclination angle display a slight influence on strength enhancement index and ductility; construction preload can degrade the plastic deformation capacity and postpone the origin appearance of contact pressure, thus making a decrease of 14.81%~27.23% in ductility. Finally, a revised equation for determining strain εscy corresponding to ultimate strength was proposed to evaluate the plastic deformation capacity of built-up square CFST columns.

• 한국항해항만학회지
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• 제38권6호
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• pp.701-708
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• 2014

본 연구는 시스템 다이내믹스법을 이용하여 인천항 배후단지가 인천항 컨테이너 물동량에 미치는 영향을 분석하는 것을 연구의 목적으로 하였다. 시뮬레이션을 위해 사용된 변수는 환율(달러), 경상수지, 자본수지, 일본 교역량, 중국 교역량, 수출 단가지수, 수입 단가지수, 인천항 교역액 등의 거시 경제지표이며, 추가로 인천 항만배후 단지가 인천항 물동량에 어떠한 영향을 주는지를 검증하기 위하여 현인천항만 배후단지 입주기업의 매출액, 컨테이너물동량, 임대료, 종업원 수를 이용하여 민감도 분석을 시행하였다. 예측된 결과값의 정확도를 측정하기 위해 절대평균오차비율(MAPE) 검증을 실시하였으며, 10% 이내의 결과값을 얻어 매우 정확한 예측으로 판정되었다. 민감도 분석결과, 항만 배후단지 입주기업의 물동량이 인천항 컨테이너 물동량 증가에 가장 많이 기여하는 것으로 나타났으며, 임대료가 높을수록 물동량이 줄어드는 것으로 분석되었다.

• 한국의학물리학회지:의학물리
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• 제23권2호
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• pp.99-105
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• 2012

치료 테이블 회전, 아크 간 콜리메이터 회전 각도가 광자에너지별 전립선암 래피드아크 치료계획의 선량분포에 미치는 영향에 대해 조사하였다. 6 MV와 10 MV 광자 에너지에 대해 2 아크(two arcs)를 사용하여 아크 간 콜리메이터 각도 차이가 $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, $90^{\circ}$인 경우와 치료 테이블 회전 유무에 따라 치료계획을 시행하였다. 선량 최적화를 위한 표적 및 중요 장기의 선량 제한치(dose constraints)를 동일하게 적용하여 계산하였고 선량 분포를 평가하기 위해 CI (Conformity index), HI (Homogeneity index), QOC (Quality of Coverage) 등의 정량화된 선량 지표를 구하여 각 치료계획의 최적화 결과를 비교하였다. 그 결과 치료계획표적용적과 중요장기의 선량 지표 차이는 3.6% 이하로 광자에너지, 치료테이블, 아크 간 콜리메이터 각도의 영향은 크지 않았다. 그러나 표적에서 먼 정상조직의 경우 저 선량 영역 차이가 크게 나타났다. 좌우 대퇴골두의 V15%는 6 MV 일 때 각각 6.4%, 5.5% 높았고, 치료테이블 회전 시에는 23.4%, 24.1% 높게 나타났다. 표적에서 먼 영역(Far Region)의 V10%는 6 MV 일 때 54.2 cc, 치료테이블 회전이 없을 때 343.4 cc, 아크 간 콜리메이터 각도가 $0^{\circ}$일 때 457.8 cc 크게 나타났다.