• Journal of electromagnetic engineering and science
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• 제10권4호
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• pp.276-281
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• 2010

In this paper, an electromagnetic induction on a telecommunication line by the distribution line of a power provision system or a feeder line of an electrified railway system has been verified through experiments. The basic cause of induction occurrence by these practical power provision systems is the returning current through the earth. This principle has been confirmed by the experiments documented in this paper which implemented these mechanisms to incur an induction. Experimental methods were used to produce the returning current through the earth. The experiment to find a relationship between inducing strength and the distance between the two phase lines in a power provision line has also been included to confirm that, when the distance is enlarged, the induction effect increases as the cross-nullification effect of magnetic fluxes decreases. An experiment for the existence of a shielding effect by another conduction length material has been addedas a protection measure against the induction.

• 자원ㆍ환경경제연구
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• 제29권2호
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• pp.195-217
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• 2020

지속가능한 발전을 달성하기 위한 방안으로 에너지 집약도 개선이 주목받고 있다. 에너지 가격과 기술 수준은 에너지 집약도에 영향을 미치는 주요한 요인으로 세 변수의 연관성에 관한 실증연구는 해외를 중심으로 진행되어왔다. 그러나 우리나라를 대상으로 한 연구는 드물다. 이에 본 연구에서는 우리나라를 대상으로 에너지 집약도, 에너지 가격, 총요소생산성 간 동태적 관계를 분석하였다. 분석 결과 세 변수는 장기균형관계를 형성하며, 총요소생산성의 증가는 장·단기에서 모두 에너지 집약도를 감소시키는 것으로 나타났다. 총요소생산성의 증가가 에너지 집약도 개선에 미치는 효과는 단기보다 장기에 더 큰 것으로 나타났다. 반면 에너지 가격은 에너지 집약도에 유의미한 영향을 미치지 못하였다. Granger 인과성 검정 결과, 에너지 집약도와 총요소생산성은 상호 Granger 인과하지만, 에너지 가격은 약외생적인 것으로 나타났다. 우리나라의 에너지 집약도 개선을 위해서는 전반적인 기술 수준의 개선이 필요하며, 단기적인 처방보다 장기적인 관점에서 정책적 방안을 마련하는 게 바람직하다는 것을 확인할 수 있었다.

• Journal of Periodontal and Implant Science
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• 제36권4호
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• pp.829-837
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• 2006

Halitosis, defined as an unpleasant oral odor, is a commonly experienced condition with a variety of etiological factors and may cause a significant social or psychological handicap to those suffering from it, In most cases, halitosis originates within the oral cavity itself and patients with periodontal disease often suffer from oral malodor, The most common cause of this disease is related to microbiota which reside on the tongue and in the periodontal pocket, This study was undertaken to examine the effect of full mouth disinfection including tongue scraping on oral malodor in a group of patients with chronic periodontitis, The relationship between halitosis and oral health status was also investigated, The volatile sulfur compounds (VSC) scores were significantly correlated with Plaque Index, Bleeding Index, pocket depth, and tongue coating score, The organoleptic ratings were significantly associated with Plaque Index, Bleeding Index. and tongue coating score, The VSC scores and organoleptic ratings correlated strongly with each other. Full mouth disinfection resulted in a significant reduction in the VSC scores. organoleptic ratings, and self-perception of malodor up to 12 weeks, This study indicates that in patients with chronic periodontitis. a full mouth disinfection including tongue scraping has a significant effect in the treatment of oral malodor.

• 국제학술발표논문집
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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• pp.281-290
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• 2017

As various stakeholders are involved in construction projects, disputes between the parties are more likely to occur, which is a very important issue for the participants in the projects. Claims in construction projects, however, are very complex and thus difficult to manage. In particular, as the cause of a claim in the preceding stage that has not been resolved in a timely manner has an effect on the cause of a claim in the following stage, it is difficult to find a point of compromise regarding a claim caused by the relationship between the causes that occur in the preceding and following stages. In this regard, this study sought to examine the rules for the generation of change order claims, which occur most frequently among the construction claims, and thus to select the key management targets through the analysis of the relationship between the causes of claims arising in the preceding and following stages for the efficient management of claims. It is expected that the use of rules for the generation of change order claims as well as of representative and similar cases will help the construction practitioners in judging claims, considering the relationships among the causes of the claims. Meanwhile, in this study, association analysis was conducted regarding the causes of the occurrence of change order claims in a design-build delivery method, and therefore, it is necessary to verify the effectiveness of the method when applied to other delivery methods.

• 한국정밀공학회지
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• 제24권7호
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• pp.126-132
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• 2007

Pressure-induced decubitus is a serious disease among the elderly people. Interface pressure occluding vascular perfusion is known to be a cause of decubitus. Therefore, it is essential to quantify the relationship between vascular perfusion and interface pressure among the elderly people to understand more about decubitus. Nine healthy elderly people (57.8$\pm$ 5.6 years, 63.3$\pm$ 7.0kg, 1.68$\pm$ 0.05m) were participated. Three healthy young people (31.7$\pm$ 3.2 years, 74.7$\pm$ 8.4kg, 1.75$\pm$ 0.04m) were also examined to be compared with the elderly group. Capillary vascular perfusion on the ischial tuberosity was recorded in the sitting posture as pressures were applied from 15mmHg to 135mmHg. The average interface pressure to occlude vascular perfusion (the average occlusion pressure) under the ischial tuberosity was 115.7mmHg in the elderly group. This value was not significantly different from the average occlusion pressure of the young group. Obesity effect on the occlusion pressure was investigated among the elderly group. The result was not significantly different between the obesity and the normal group in this study. This is a preliminary study to unveil the complicated cause of pressure-induced decubitus associated with occlusion of vascular perfusion. More subjects are required for the future study.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권2호
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• pp.252-261
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• 2014

A Bayesian network (BN) based fault diagnosis framework for semiconductor etching equipment is presented. Suggested framework contains data preprocessing, data synchronization, time series modeling, and BN inference, and the established BNs show the cause and effect relationship in the equipment module level. Statistically significant state variable identification (SVID) data of etch equipment are preselected using principal component analysis (PCA) and derivative dynamic time warping (DDTW) is employed for data synchronization. Elman's recurrent neural networks (ERNNs) for individual SVID parameters are constructed, and the predicted errors of ERNNs are then used for assigning prior conditional probability in BN inference of the fault diagnosis. For the demonstration of the proposed methodology, 300 mm etch equipment model is reconstructed in subsystem levels, and several fault diagnosis scenarios are considered. BNs for the equipment fault diagnosis consists of three layers of nodes, such as root cause (RC), module (M), and data parameter (DP), and the constructed BN illustrates how the observed fault is related with possible root causes. Four out of five different types of fault scenarios are successfully diagnosed with the proposed inference methodology.

• 보건행정학회지
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• 제13권4호
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• pp.99-114
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• 2003

This study was performed to determine the effect of social class distribution as measured by lower social class rate on all cause and cause specific mortality in Korea. I obtained data on social class, fiscal autonomy of municipalities, number of medical doctors, region(Si/Gun) from 1955 Korea Census Data and Regional Statistics Data. And all of the data on mortality adjusted for age for 1995 for each district from the National Statistics Office. Lower social class rate ranged from 18.9％ for Kangnam gu to 85.7％ for Imsil gun and age standardized mortality ranged from 385/100,000 population for Kangnam go to 803/100,000 population for Sinan gun. Lower social class showed had a significant correlation with total mortality adjusted for age(r=0.81, p<0.0001). The association of the rate to total mortality remained highly significant after adjusted for number of medical doctors per 1,000 population, fiscal autonomy of municipalities and region(p<0.0001). Effects of the lower social class were also found for neoplasm (p=0.0008)； cardiovascular disease (p<0.0001)； infectious disease(p=0.0115)； respiratory disease(p=0.0085)； gastrointestinal disease(p<0.0001)； accident ＆ poisoning (p<0.0001). The findings suggest that policies that deal with the inequality in social class may have an important impact on the health of the population.

• Clinical and Experimental Pediatrics
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• 제45권12호
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• pp.1546-1550
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• 2002

목 적: 본 저자들은 VGB과 시야결손과의 관련성을 알기 위해 본 연구를 시행하였다. 방 법: 간질로 진단 받고 VGB을 추가 복용으로 치료를 시행한 환아 중 발달 연령이나 인지 연령이 8세 이상인 환아 78명을 대상으로 하였다. 시야검사는 Humphrey 자동 시야측정계로 시행한 후 결과가 의심이 되면 Goldman 시야측정계로 검사를 즉시 다시 시행하였으며, 이들은 다시 6개월 후에 재검을 실시하였다. 결 과 : 본 연구에서는 78명 중 5명에게 의증이 있었으나 재검시 다시 정상으로 나와 시야결손이 있는 환아는 없었다. 결 론: 본 조사에서 VGB은 시야결손을 일으키는 약물로 나타나지는 않았다. VGB의 시야결손으로 사용에 제한을 두기보다 다른 약으로 조절이 되지 않는 부분발작과 영아연축의 치료에 초기 선택 약물로 조심스럽게 사용하면 무방할 것으로 생각되어진다. 이와 함께 시야결손의 선별검사가 추천되며, VGB을 복용하는 소아에게 있어 정기적인 검사가 필요하겠다.

• 한국게임학회 논문지
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• 제11권6호
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• pp.115-125
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• 2011

최근 스마트폰 사용자의 급격한 증가는 스마트폰게임 시장의 큰 성장을 가져왔으며 고 부가가치 시장으로서의 입지를 굳히고 있다. 이에 새롭게 부각되는 스마트폰게임에 대한 다각적인 연구가 야기되고 있으나 기존 연구가 스마트폰 이전의 휴대폰을 대상으로 연구가 대부분 이루어져 스마트폰 중심의 새로운 확장 연구가 필요한 실정이다. 따라서 선행연구를 통해 도출한 스마트폰게임의 구매영향요인을 토대로 구매의도, 구매행동, 만족, 추천, 지속사용 간의 영향관계를 알아봄으로서 추천과 지속사용에 영향을 미치는 핵심 요인을 도출하고자 하였다. 이를 위해 스마트폰 사용자 커뮤니티 등을 통해 수집한 설문응답자료 293부를 분석에 이용하였으며 변인들 간의 영향관계 분석에 이점을 가진 구조방정식 모델을 채택하였다. 본 연구를 통하여 얻은 핵심 요인들은 차후 스마트폰게임 관련 비즈니스 시장에서 좀 더 효율적으로 개발을 수행하고 보다 가시적인 성과를 거둘 수 있는 유용한 시사를 제공해 줄 수 있을 것이다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2004년도 International Conference Global Environmental Problems and their Health Consequences
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• pp.217-222
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• 2004

This study was conducted to estimate if the level of several chemical ingredients including alkanolamines or ethanolamines (EA) examined in the specific synthetic metalworking fluid (MWF) ‘A’ can cause anti-microbial activity and health effect. Three water-based MWF products (‘A’, ‘B’, and ‘C’) were studied every week for two months. Chemical ingredients such as formaldehyde, boron, EA, and copper were examined. In the sump where MWF ‘A’ was used, not only the total level of EA, monoethanolamine(MEA), diethanolamine(DEA) and triethanolamine(TEA), but also boron level were significantly higher than those of the other MWFs. ANOVA statistical tests indicated that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF ‘A’ were significantly higher than those in other MWF types. Correlation tests also found that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF ‘A’ are significantly correlated. We suggested the assumptions that excessive concentrations of EA, and borate at a high pH level, may cause anti-microbial resistance synergically. To demonstrate this assumption, additional study is needed to examine the relationship between the levels of microbes and excessive concentrations of EA, and borate at a high pH level.