• Environmental Analysis Health and Toxicology
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• 제21권2호
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• pp.173-184
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• 2006

From the harmfulness expectation test conducted through a toxicity anticipation program, methylcyclohexane turned out to be harmful and simulative, but no carcinogenicity was anticipated. In a four-hour acute inhalation toxicity test, the result showed that lethal concentration ($LC_{50}$) was 3,750 ppm (15,054 mg/L), which was identified as a harmful substance on the basis of the harmful substance classification standard $2 of the Industrial safety and health law. methylcyclohexane fell under the category $4(2,500 substance from the GHS standard acute toxicity harmfulness classification. Also, from subchronic inhalation toxicity test that included 6 hours a day, five days a week, and for 13 weeks, we could observe weight, activity, long term weight, blood and blood biochemical influence from the exposure of test substance. No-observed effect level (NOEL) was determined below $100{\sim}400ppm$ inboth male and female. This material falls under the Category 2 ($50{\sim}250ppm/6hours/90days$) in the GHS (Globally Harmonized System) standard trace long-term whole body toxicity repeated exposure, and can be classified as a harmful substance in accordance with the Industrial Safety and Health Law harmful substance standard $NOEL{\leq}0.5mg/L/6hr/90day$ (rat).

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.94-98
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• 2009

정보 수준의 격차 해소 및 이분야간 정보 교류를 위한 목적으로 각 분야별 전문 용어를 표준화하는 움직임이 활발하게 진행되고 있다. 각 분야에서 생성되는 전문 용어를 등록/관리하고, 이를 표준 전문 용어로 재정하고 공유하는 과정은 매우 복잡할 뿐만 아니라, 전문 용어와 관련된 많은 사람들이 표준화 과정을 공유하면서 진행되어야 한다. 또한 시간의 흐름에 따라 전문 용어도 변화할 수 있기 때문에 전문 용어 표준화 과정에서의 이력 관리는 물론 세계화에 따른 다국어와의 대역 정보 관리도 필요하다. 많은 기관 및 다양한 분야에서 전문 용어 표준화 작업을 수행하고 있고, 이에 따라 용어 표준화, 용어 이력 관리 및 표준 용어의 공개 서비스를 효율적으로 지원할 수 있는 시스템에 대한 수요도 증가하고 있다. 본 연구에서는 전문 용어의 등록, 표준화 과정 지원, 표준 용어로 제정된 용어를 일반 사용자에게 서비스하는 것을 지원하는 전문 용어 표준화 관리 시스템을 개발하였다.

• 한국물환경학회지
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• 제34권2호
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• pp.157-163
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• 2018

This study aims to determine the pollution levels of nine kinds of heavy metals (As, Cd, Cu, Cr, Hg, Mn, Ni, Pb, and Zn) in Lake Shihwa, which is susceptible to the inflow of pollutants, and the levels of heavy metal exposure in its fish and shellfish. Shihwa Lake's water quality did not exceed the short-term standard for protection of marine ecosystems, but concentrations of As, Cu, Cr, Hg, Ni, and Zn exceeded the long-term standard for protection of a marine ecosystem. In comparison to findings in prior research, performed in 2010, levels of Cr, Ni, As, and Zn are now 4.1 times lower. However, when compared to Saemangeum Lake, the environment is similar to that of Lake Shihwa, Cu, Ni, Hg, Mn, and Zn were 244.4 times higher. The levels of Pb, Cd, and Hg in fish's muscles did not exceed the average values set by the marine safety standard. However, when compared to the fish from the Korean coast, the levels of heavy metals were 9.7 times higher, on average. The levels of heavy metals in fish's livers were on average 26.8 times higher than in the muscles. In the case of shellfish, the levels of Pb, Cd, and Hg did not exceed the standard values, but in comparison to the shellfish from the south coast, the levels of heavy metals were 6.2 times higher on average. In particular, Mn (153.5 times higher) from fish and Cd (14.7 times higher) from shellfish were found in high amounts, indicating a concerning level of these specific heavy metals.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(1)
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• pp.151-158
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• 2003

Recently, there has been considerable interest in the influence of El Nino/Southern Oscillation (ENSO) on a global scale. ENSO has been measured by a simple index called Southern Oscillation Index (SOI). The statistical characteristics of SOI have been also focused to reveal the influence of ENSO. The SOI trend shows that El Nino events are generally getting stronger and more frequently occurring than La Nina events. However, the variation of SOI has varied significantly in a long-term. The SOI values are computed using the mean value and its standard deviation of the base period from 1951 to 1980. In the present study, the different base periods are applied to compute the SOI values and the influence of the different base periods is investigated in detail to reveal the long-term variation of SOI From the results, we could conclude that the present SOI should be carefully considered as a criterion to judge whether the El Nino and La Nina events are occurring.

• 대한심미치과학회지
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• 제10권1호
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• pp.56-70
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• 2001

The use of resin-bonded fixed partial dentures described in the early 1980s caused an conservative way to preserve tooth structure in the restorative dental community. The treatment of patients with requires long term analysis of clinical application and basic research. Failure rates of these prosthesis ranged from 3% to 55%. These varieties were orginated by different techniques, materials, tooth preparation methods and diverse clinical situations. This article review was focused on the standard long term results and in vitro studies on bond strength between metal and teeth. From this, many useful clinical guidelines to RBFPD could be adopted to clinical dentistry. For successful results, careful case selection and good clinical skills are needed. And appropriate techniques for each situations should be adopted. Also, RBFPD using new materials like all-ceramics, FRC/Ceromer was introduced.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.41-76
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• 2001

Rheumatoid arthritis is an incurable chronic inflammatory and destructive arthopathy that affects 1% of the population world-wide. It has substantial personal, social and economic costs. The long-term prognosis is poor: 80 percent of affected patients will become disabled within 20 years after onset of disease. Medical costs of rheumatoid arthritis average ∼$ 6000 (US) per patient (1), Current antirheumatic drugs have limited efficacy and many side effects and more importantly they do not improve the long-term prognosis of rheumatoid arthritis (2). After a decade of few notable advances in therapy, several biological response modifiers that target pathophysiological processes in the disease have now emerged in the clinic. These new drugs are termed biological agents, and although information about their use in the clinic is still limited to short term treatment, they appear to have the ability to modify disease progress. In addition, COX-2 selective agents have now been approved that have comparable efficacy with standard NSAIDs, but fewer gastrointestinal side effects (3). Thus today many more therapeutic options are suddenly open to patients that even five years ago had little hope of relief from chronic pain and inflammation.

• 가정과삶의질연구
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• 제21권4호
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• pp.1-10
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• 2003

This paper compares the time perspective between Korean and American college students and examines the difference of it according to gender and social status of them. The subject of this study were 385 Korean students and 385 American counterparts. The data were collected by survey with questionnaires and analyzed by SPSS program for the frequency, percentile, mean, standard deviation, t-test, one-way ANOVA and Duncan test. The results indicate that American students have more long-term personal direction than Korean counterparts and the effects of gender and social status are different in Korea and America. Korean students showed no difference according to these two variables but female America students indicate more long-term personal direction than male students and the time perspectives were different according to social status in America.

• 전기학회논문지
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• 제58권9호
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• pp.1695-1699
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• 2009

This paper analyzed the characteristics of the demand of electric power in Jeju by year, day. For this analysis, this research used the correlation between the changes in the temperature and the demand of electric power in summer, and cleaned the data of the characteristics of the temperatures, using the coefficient of correlation as the standard. And it proposed the algorithm of forecasting the short-term electric power demand in Jeju, Therefore, in the case of summer, the data by each cleaned temperature section were used. Based on the data, this paper forecasted the short-term electric power demand in the exponential smoothing method. Through the forecast of the electric power demand, this paper verified the excellence of the proposed technique by comparing with the monthly report of Jeju power system operation result made by Korea Power Exchange-Jeju.

• Journal of Gastric Cancer
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• 제20권4호
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• pp.345-354
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• 2020

Early detection of gastric cancer is crucial because the survival rate can be improved through curative treatment. Although surgery and gastrectomy with lymph node dissection remain as the gold standard for curative treatment, early gastric cancer (EGC) with negligible risk of lymph node metastasis can be treated with endoscopic resection (ER), such as endoscopic submucosal dissection. Among gastric cancers, undifferentiated-type cancer is distinguished from differentiated-type cancer in various aspects in terms of clinical features and pathophysiology. The undifferentiated-type cancer is also known to be associated with an aggressive behavior and a poor prognosis. Therefore, the indication of ER for undifferentiated EGC is limited compared with differentiated-type. Recent studies have reported that ER for undifferentiated EGC is safe and shows favorable short- and long-term outcomes. However, it is necessary to understand the details of the research results and to selectively accept them. In this review, we aimed to evaluate the current practice guidelines and the short-term and long-term outcomes of ER for undifferentiated type EGC.

• 센서학회지
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• 제30권5호
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• pp.349-356
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• 2021

The Korea Research Institute of Standards and Science (KRISS), a National Metrology Institute of Korea, participated in the second-round of the international key comparison CCT-K7.2021 of triple point of water (TPW) cells. For the key comparison, three TPW cells, one of which had been used in the old CCT-K7 comparison, were assigned as the national standard of the TPW. The temperature difference (ΔT) between the average of the new and old national standards and ΔT between the new national standard and the transfer standard were measured. The comparison between the new and old national standards indicated a temperature increase of 69.5 µK after both the standards were corrected for the isotopic composition. The uncertainty of the national standard of the TPW temperature was 28 µK, and the uncertainty of ΔT was 14 µK. Three aspects of improvements in the new comparison compared to the old one were noted: (1) inclusion of two quartz cells in the national standard strengthens its long-term stability; (2) the standard deviation associated with the measurement of ΔT was reduced from 21 µK to 9.6 µK; (3) and the measured immersion profile of the TPW cells was much closer to the theoretically predicted dependence.