• The Journal of Engineering Geology
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• v.25 no.1
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• pp.115-129
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• 2015

The cut-slope of a large-sectional tunnel portal is recognized as a potential area of weakness due to unstable stress distribution and possible permanent displacement. This paper presents a case study of a slope failure and remediation for a large-scale cut-slope at a tunnel portal. Extensive rock-slope brittle failure occurred along discontinuities in the rock mass after 46 mm of rainfall, which caused instability of the upper part of the cut-slope. Based on a geological survey and face mapping, the reason for failure is believed to be the presence of thin clay fill in discontinuities in the weathered rock mass and consequent saturationinduced joint weakening. The granite-gneiss rock mass has a high content of alkali-feldspar, indicating a vulnerability to weathering. Immediately before the slope failure, a sharp increase in displacement rate was indicated by settlement-time histories, and this observation can contribute to the safety management criteria for slope stability. In this case study, emergency remediation was performed to prevent further hazard and to facilitate reconstruction, and counterweight fill and concrete filling of voids were successfully applied. For ultimate remediation, the grid anchor-blocks were used for slope stabilization, and additional rock bolts and grouting were applied inside the tunnel. Limit-equilibrium slope stability analysis and analyses of strereographic projections confirmed the instability of the original slope and the effectiveness of reinforcing methods. After the application of reinforcing measures, instrumental monitoring indicated that the slope and the tunnel remained stable. This case study is expected to serve as a valuable reference for similar engineering cases of large-sectional slope stability.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.145-148
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• 2003

The Kunang cave paleolithic site is located at Tanyang [$N37^{\circ}2'$, $128^{\circ}21'E$], Chungbuk Province, which is in the Central part of the Korean peninsula. The cave is developed at 312 amsl in a karstic mountainous area. The South Han River flows across this region and other caves can also be found near the river. The site was discovered in 1986 and excavated 3 times by the Chungbuk National University Museum until now. The cave was wellpreserved from modem human activities until the first discovery. The full length of the cave is estimated to be ca. 140 m. However, a spacious part up to 11 m from the entrance has been excavated. Eight lithological units are divided over the vertical profile at a depth of 5 m. Each unit is deposited in ascending order as follow: mud layer (Unit 9), lower complex (Unit 8) which is composed of angular blocks and fragments with a muddy matrix, lower travertine layer (Unit 7； flowstone), middle complex (Unit 6; cultural layer) which is composed of fragments with a muddy matrix, middle travertine layer (Unit 5； flowstone), yellowish muddy layer (Unit 4), upper complex (Unit 3； cultural layer) which has a similar composition to Unit 8. the upper travertine layer (Unit 2； flowstone), and finally surface soil layer (Unit 1). The most abundant vestiges in the cultural layers are the animal bones. They are small fractured pieces and mostly less than 3 cm in length. About 3,800 bone pieces from 25 animal species have been collected so far, 90 percent of them belonging to young deers. Previous archaeological study of these bone pieces shows thatprehistoric people occupied the cavenot for permanent dwelling but for temporary shelter during their seasonal hunting activity. More extensive studies of these bones together with pollen analysis are in progress to reconstruct the paleoenvironment of this cave. Only a single date (12,500 BP) obtained from a U-Th measurement of the upper travertine layer was previously available. In spite of the importance of the cave stratigraphy, there was no detail chronological investigation to establish the depositional process of the cultural layers and to understand the periodic structure of the cave strata, alternating travertine floor and complex layers. We have measured five 14C age dating (38900+/-1000, 36400+/-900, 40600+/-1600, more than 51000 and 52000 14C BP) using Seoul National University 14C AMS facility, conducted systematic process of the collagen extraction from bone fragments samples. From the result, we estimate that sedimentation rate of the cave earth is constant, and that the travertine layers, Unit 2 and Unit 3, was formed during MIS 5a(ca. 80 kBP) and MIS 5c (ca. 100 kBP) respectively. The Kunang Cave site is located at Yochonli of the region of Danyang in the mid-eastern part of Korea. This region is compased of limestones in which many caves were found and the Nam-han river flows meanderingly. The excavations were carried out three times in 1986, 1988, and 1998.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10505-10508
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• 2015

Background: Breast cancer is an important cause of death among women. One way of classifying different forms of breast cancer is by molecular features, usually in terms of the four subtypes: luminal A, luminal B, HER2-enriched, and triple negative. Objectives: This study aimed to investigate the association between molecular subtypes and survival among breast cancer patients treated with radiotherapy. Materials and Methods: A retrospective cohort study was conducted. The subjects were 272 breast cancer patients who had received treatment in the radiotherapy unit at Srinagarind Hospital, Thailand, between 1 January, 1999, and 31 May, 2009. The end of the study was 1 June, 2014. Overall survival was defined as the time elapsing between initial registration at the radiotherapy unit and death or the end of the study. Survival curves were estimated by the Kaplan-Meier method, and a multivariate analysis was performed using Cox's proportional hazard regression model. Results: The patient mean age was $47.5{\pm}10.4$ at the time of diagnosis. Of the 272 patients, 146 (53.7%) were classified as luminal A, 12 (4.4%) as luminal B, 30 (11.0%) as HER2-enriched, and 84 (30.9%) as triple negative. The overall survival rates at 1, 3 and 5 years were 87.1%, 68.4% and 59.2%, respectively. According to molecular subtypes, HER2-enriched patients had the lowest 5-year survival rate (30.0 %, 95%CI: 15.02-46.55). The median follow-up time was 8.37 years. In the Cox model analysis a higher risk of death was found for patients with HER2-enriched ($HR_{adj}=3.34$, 95%CI:1.96-5.67), triple negative ($HR_{adj}=2.17$, 95%CI: 1.44-3.27), and stage IIlB ($HR_{adj}=2.20$, 95%CI: 1.16-4.17) cancers. Conclusions: The worst survival rates were among patients classified as HER2-enriched, triple negative and at stage IIIB. Early detection and an advanced treatment modality are needed to help these patients.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.139-143
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• 2014

Although correlations between platelets and lung cancer has been recognized, effects on non-small cell lung cancer (NSCLC) metastasis remain to be determined in detail. In the present study, wound healing assays revealed a role of platelets in NSCLC cell migration. Thus the mean migration rate of lung adenocarcinoma A549 cells was significantly elevated after co-culture with platelets ($81.7{\pm}0.45%$ vs $41.0{\pm}3.50%$, P<0.01). Expression of GAPDH was examined by reverse transcription-polymerase chain reaction to study the effect of platelets on NSCLC cell proliferation. The result showed that the proliferation of A549 and SPC-A1 cells was not affected. Mouse models were established by transfusing A549 cells and SPC-A1 cells into mice lateral tail veins. We found tumor metastasis nodules in lungs to be increased significantly after co-transfusion with platelets (in A549, $4.33{\pm}0.33$ vs $0.33{\pm}0.33$, P=0.01; in SPC-A1, $2.67{\pm}0.33$ vs $0.00{\pm}0.00$, P=0.01). In addition, consecutive inoperable patients with newly diagnosed NSCLC (TNM stage III or IV) between January 2009 and December 2011 were retrospectively reviewed. Using the Kaplan-Meier method, NSCLC patients with a high platelet counts demonstrated a significantly shorter progression free survival compared with those with a low platelet count (> $200{\times}10^9/L$, 3 months versus ${\leq}200{\times}10^9/L$, 5 months, P=0.001). An elevated platelet count was also identified as an independent prognostic factor by Cox regression analysis for prgression free survival (adjusted hazard ratio: 1.69; 95% CI: 1.16, 2.46; P=0.006). This study suggested that platelets might contribute to the hematogenous metastatic process by promoting cancer cell migration, which eventually affects the prognosis of NSCLC.

• Korean Journal of Veterinary Service
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• v.25 no.2
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• pp.117-126
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• 2002

Contamination levels of pathogenic microorganisms in 145 cases of beef, which were distributed in Gwangju province, had been investigated in each distributed stage and also monitored by general bacterial count and E coli count index. General bacterial count of beef from the slaughterhouse was 10$^4$cfu/g less than the level of promotion(10 cfu/$\textrm{cm}^2$) and E coli count index was also under the level of 10$^2$cfu/$\textrm{cm}^2$ recommended level of the ministry of agriculture and forestry. Pathogenic microorganisms were detected from 23.2% of samples in the consumption stage, 12.5% in the slaughtering stage and 5.6% in the transporting and processing stage. Staphylococcus aureus was isolated in the largest number and its ratio was 9.0%, listeria monocytogenes 5.5% and salmonella spp 1.4%. There were no samples that bacteria had been detected dually. E coli O157:H7 and campylobacter jejuni were not isolated. In raw and chilled beef, isolation rate of pathogenic microorganisms were 13.3% and 16.5% each. Especially in raw beef, L monocytogenes was. isolated in 3 samples among 30 cases (10%) and S aureus in one sample (3.3%). According to a scale of meat store, isolation rates of pathogenic microorganisms were different. It was 28.6% in the small-scale meat store and 16.7% in the large-scale meat store each. Four cases (16.7%) of S aureus were isolated in the large-scale meat store and seven cases (20.0%) of L monocytogenes and 2 cases (5.7%) of salmonella spp were isolated in the small-scale meat store. S aureus was isolated in two places among 10 feeding facilities of the elementary school. This result shows that the sanitation of elementary school feeding facilities is so poor and more careful policy consideration is needed. Eleven strains of S aureus isolated showed ${\beta}$-hemolysis on blood agar, 1 strain ${\alpha}$-hemolysis, and 1 strain ${\gamma}$-hemolysis. Isolated strains of L monocytogenes were reconfirmed in 560 bp by PCR. Conclusively, these results show that the sanitary condition in the stages of slaughtering, transportation-processing and consumption influences the degree of pathogenic microorganisms contamination in beef severely It is necessary to apply thoroughly hazard analysis critical control point in a process of beef distribution and also to develop rapid test methods for microorganism diagnosis. This effort is very important for the supply of safe and clean meat from farm to table and helpful for the improvement of public health.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.490-494
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• 2008

본 연구에서는 상수도 배수관로의 내 외부적 특성에 따라 개별관로를 정의하는 방법을 연구대상 지역의 배수관로 파손 데이터베이스에 적용하여 비례위험모형을 구축하였다. 연구에 사용된 자료는 연구대상지역의 배수관로의 제원 및 파손시기를 포함하는 관로 파손데이터베이스, 관로매설지역의 급수인구 및 수압범위에 관한 자료를 포함하는 GRID 데이터베이스와 관로매설지역의 토지개발 정도에 관한 자료를 포함한다. 이러한 자료를 이용하여 관로를 순차적 파손경험에 따라 7개의 생존시간군(STG I $\sim$ VII)으로 구분하고 각 생존시간군에 대한 비례위험모형(Model I $\sim$ VII)을 구축하였다. 이러한 모형을 이용하여 관로의 파손횟수가 증가하는 동안 파손에 영향을 미치는 인자의 변화와 그 효과를 파악하였으며, 또한 추정된 공변수의 위험비율을 분석함으로써 관로의 제원 혹은 매설환경, 급수인구 등에 따른 위험률의 상대적인 변화를 분석하였다. 또한 비례 위험모형의 구축과정에서 관로의 파손에 영향을 미치는 공변수의 비례성 가정을 검토하여 시간종속형 공변수를 모형화하였으며, 모형의 이탈잔차(deviance residual)를 분석하여 모형의 적합성을 검토하였다. 본 연구에서 구축된 비례위험모형에 대해 Shoenfeld 잔차를 이용한 스코어 잔차의 변화(score process)를 검토한 결과, Model I 과 Model II 에 대해서는 공변수의 시간종속 효과가 발견되었다. Model I에 대해서는 관로재질과 급수인구의 영향이 시간에 따라 변하며 Model II에서는 급수인구의 영향만이 시간에 따라 변하는 것으로 나타났다. 한편 Model III $\sim$ Model VII 들에 대해서는 공변수의 영향이 시간에 따라 변하지 않는 것으로 나타났다. 각 생존시간군에 대해 관로재질, 토지개발정도, 관로길이 및 급수인구의 변화가 관로의 상대적 누수위험률에 미치는 영향을 상대위험률의 95% 신뢰구간을 고려하여 정량적으로 산정하였고, 시간 종속형 공변수로 모형화된 공변수는 시간에 따른 공변수 영향의 변화를 분석하였다. 순차적 파손사건에 대한 비례위험모형의 구축 결과 생존시간군(STG) I의 기저위험률은 매설 후 대략 450개월까지는 파손 위험률이 '0'에 가까우나 그 이후로 급격히 증가하다가 매설 후 약 700개월에 이르러서는 약간 감소하고 약 850개월 이후에는 다시 급격히 증가한다. STG II의 기저위험률은 첫 번째 파손 후 약 300개월이 되면 위험률이 급격히 증가하는 것으로 나타났다. STG III $\sim$ STG VII의 기저위험률은 이차함수의 형태를 띄며, 특히 STG V, STG VI 및 STG VII의 기저위험률은 욕조형 곡선(bathtub curve)의 형태를 가진다. 각 생존시간군의 기저생존함수의 생존확률 '0.5'에 해당하는 기저중간생존시간에 대한 분석으로부터 파손횟수가 많아질수록 순차적 파손사건 사이의 경과시간은 감소하는 것으로 나타났다. 이러한 기저생존시간에 대한 경향은 관로의 파손횟수가 많아질수록 관로의 일반적은 내구성은 감소하기 때문인 것으로 분석된다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.164-175
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• 2019

Installation of digital tachograph, black box, and ADAS have been enforced to commercial vehicles for preventing violent driving and accidents by the Traffic Safety Act in Korea. Nevertheless, the damage caused by road hazards has increased 1.5 times in 2016 compared to 2013. So, developing new technologies that can identify road hazard using the sensors installed in commercial vehicles are conducting by the Ministry of Land, Infrastructure and Transport. As a part of the technologies, this research analyze the error range of GPS installed in commercial vehicles that vary according to the driving speed. As a result, the average error was 9.72m at the driving speed of 100km/h, and the error was 2.1 times larger than the average error of 4.69m at the driving speed of 40km/h. The event point proper integration/separation range(m) was analyzed to be 20m with a recognition rate of 90% or more at the same point regardless of driving speed. The results of this research can be used as basic data for improving the accuracy of location-based data would be collected using commercial vehicles.

• Journal of Radiation Protection and Research
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• v.32 no.1
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• pp.27-34
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• 2007

In this paper, We are evaluated about bio-signal between general workers and nuclear medicine workers which is more radiation exposure relatively. In order to reciprocal evaluated two group, we experimented nuclear medicine workers in Chung-Buk National University Hospital at department of nuclear medicine and worker in Chon-Nam National University Hospital at CT room, general radiographic room, medical recording room, receipt room, general office room. Used of experimental Equipments as follows, for a level of radiation measurement by pocket dosimeter which made by Arrow-Tech company, for heart rate and blood pressure measurement by TONOPORT V which made by GE medical systems company, for heat flux and skin temperature and energy expenditure measurement by Armband senseware 2000 which made by Bodymedia company. Result of experiment obtains as follows: 1) Individual radiation exposure is recorded 3.05 uSv at department of nuclear medicine and order as follows CT room, general radiograpic room, medical recording room, receipt room, general office room. Department of nuclear medicine more 1.5 times than other places. 2) Radiation accumulated dose is not related to Heat flux, Skin temperature, Energy expenditure. 3) Blood pressure is recorded equal to nuclear medical workers, general officer, general people about systolic blood pressure and diastolic blood pressure. Compared to blood pressure between nuclear medical works which is more radiation exposure and other workers was not changed. Consequently, more radiation exposed workers at nuclear medicine field doesn't have hazard.

• Journal of Preventive Medicine and Public Health
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• v.49 no.6
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• pp.394-405
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• 2016

Objectives: The survival outcomes of antiretroviral treatment (ART) programs have not been systematically evaluated at the state level in India. This retrospective study assessed the survival rates and factors associated with survival among adult human immunodeficiency virus (HIV)-infected patients in Andhra Pradesh, India. Methods: The present study used data from 139 679 HIV patients aged ${\geq}15$ years on ART who were registered from 2007 to 2011 and were followed up through December 2013. The primary end point was death of the patient. Mortality densities (per 1000 person-years) were calculated. Kaplan-Meier and Cox-regression models were used to estimate survival and explore the factors associated with survival. Results: The overall median follow-up time was 16.0 months (2.0 months for the deceased and 14.0 months for those lost to follow-up). Approximately 13.2% of those newly initiated on ART died during follow-up. Of those deaths, 56% occurred in the first three months. The crude mortality rate was 80.9 per 1000 person-years at risk. The CD4 count (adjusted hazard ratio [aHR],4.88; 95% confidence interval [CI], 4.36 to 5.46 for < $100cells/mm^3$ vs. > $350cells/mm^3$), functional status (aHR, 3.05; 95% CI, 2.82 to 3.30 for bedridden vs. normal), and body weight (aHR, 3.69; 95% CI, 3.42 to 3.97 for <45 kg vs. >60 kg) were strongly associated with the survival of HIV patients. Conclusions: The study findings revealed that high mortality was observed within the first three months of ART initiation. Patients with poor baseline clinical characteristics had a higher risk of mortality. Expanded testing and counseling should be encouraged, with the goal of ensuring early enrollment into the program followed by the initiation of ART in HIV-infected patients.

• Fire Science and Engineering
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• v.15 no.1
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• pp.100-107
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• 2001

A Interior material, a main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Nonetheless, it has been used recklessly with undue attention to its contribution to fire in particular in entertainment occupancy and causes many victims in fire. Therefore, this study attempts to examine the current use of interior material in Korea and find out what to be improved and enhanced in terms of related regulations. Based on the comparison and analysis of the Korea regulation with those of advanced nations, suggestions are made for an effective and efficient improvement and complement to the current system. What can be suggested from this study are as follows. The use of interior material should be controlled under the unified regulation of fire-safety codes. Code should be set up so that the current construction enforcement should be applied in retroactive to those entertainment buildings that obtained a license prior to the implementation of the system certifying that the building is fire-resistant and fire-protective. The legislation should be made to control the fire-protection facilities of small-sized, underground entertainments. It should be obliged to present the blueprint displaying the use of interior material at the time of changing occupancy. Or, it should be compelled to report changes that go way without permit to the administrative office. A compulsory provision should be set up to have a fire-resistant performance to movable furniture. The classification index designating the fire hazard of interior material by flame spread rate and smoke toxicity and its test method should be established.