• 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.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.2
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• pp.91-101
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• 2007

In this study, domestic regulatory requirement was investigated for self-disposal of concrete waste from nuclear fuel processing facility. And after self-disposal as landfill or recycling/reuse, the exposure dose was evaluated by RESRAD Ver. 6.3 and RESRAD BUILD Ver.3.3 computing code for radiological assessments of the general public. Derived clearance level by the result of assessments for the exposure dose of the general public is 0.1071Bq/g (3.5% enriched uranium) for landfill and $0.05515Bq/cm^2$ (5% enriched uranium) for recycling/reuse respectively. Also, residual radioactivity of concrete waste after decontamination was investigated in this study. The result of surface activity is $0.01Bq/cm^2\;for\;{\alpha}-emitter$ and the result of radionuclide analysis for taken concrete samples from surface of concrete waste is 0.0297Bq/g for concentration of $^{238}U$, below 2w/o for enrichment of $^{235}U$ and 0.0089Bq/g for artificial contamination of $^{238}U$ respectively. Therefore, radiological hazard of concrete waste by self-disposal as landfill and recycling/reuse is below clearance level to comply with clearance criterion provided for Notice No.2001-30 of the MOST and Korea Atomic Energy Act.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.10-27
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• 2014

HAZUS-MH is a GIS-based computer program that estimates potential losses from multi-hazard phenomena: earthquakes, floods and hurricanes. With respect to seismic disaster, characteristics of a hypothetical or actual earthquake are entered into HAZUS. Then HAZUS estimates the intensity of ground shaking and calculates the correspondent losses. In this study, HAZUS was used as a part of the preparations of the future seismic events at a coastal plant facility area. To reliably characterize the target facility area, many geotechnical characteristics data were synthesized from the existing site investigation reports. And the buildings and facilities were sorted by analyzing their material and structural characteristics. In particular, the study area was divided into 17 blocks taking into account the situation of both land development and facility distribution. The ground conditions of blocks were categorized according to the site classification scheme for earthquake-resistant design. Moreover, seismic fragility curves of a main facilities were derived based on the numerical modeling and were incorporated into the database in HAZUS. The results estimated in the study area using HAZUS showed various seismic damage and loss potentials depending on site conditions and structural categories. This case study verified the usefulness of the HAZUS for estimating earthquake losses in coastal facility areas.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6715-6719
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• 2013

Objective: To explore the incidence, clinical characteristics, diagnosis and treatment strategies, prognosis of patients with malignancy-associated hypercalcemia (MAH). Methods: The data of 115 patients with MAH who were treated at the Medical Oncology Department of Chinese PLA General Hospital from Jan., 2001 to Dec., 2010 was retrospectively reviewed. Survival analysis was performed using the Kaplan-Meier method and the Cox proportional hazard model with statistic software SPSS 18.0. Results: The patients had blood calcium levels ranging from 2.77 to 4.87 mmol/L. Except for 9 cases who died or were discharged within 5 days after admission, all other patients recovered to normal blood calcium level after treatment with bisphosphonates or intravenous hydration and diuretics; their survival after occurrence of MAH was from 1 day to 4,051 days, and the median survival time was only 50 days. In the log-rank test, the male, renal metastasis, central nervous system symptoms and hypercalcemia occurring over 140 days after cancer diagnosis were predictors of poor survival (P=0.002, P=0.046, P=0.000, P=0.009). In the COX analysis, being male, central nervous system symptoms and hypercalcemia lasting over 140 days after cancer diagnosis were independent prognostic factors for survival time (RR=2.131, P=0.027; RR=3.054, P=0.002; RR=2.403, P=0.001). According to these factors, a score system was established to predict the patient prognosis and adjust the treatment. Conclusion: Cancer patients with MAH have an extremely poor median survival. Some independent factors indicate poor prognosis, including male gender, central nervous system symptoms and hypercalcemia lasting over 140 days after cancer diagnosis. The prognostic score can serve as a reference for MAH prognosis and treatment, worthy of further investigation.

• Journal of the Korean GEO-environmental Society
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• v.15 no.9
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• pp.77-85
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• 2014

Recently, the National Emergency Management Agency of Korea has been operating the National Disaster Management System. Nevertheless, there are numerous difficulties in systematic controlling the steep slope DB promptly, because the system's functions in input and control for steep slope information are merely simple. Futhermore, the hazard degrees of steep slope lands nowadays have risen suddenly in accordance with the increase rate of large scale landslides such as the landslide cases of Umyeonmountain, Chuncheon province and others or sever rain storm cases. these lead to rapid increases in frequencies of nature disasters nationally. therefore, it is needed to develop the GIS-based integrated management system for steep slope information in order to manage disasters in advance or high-degree control. This study shows the national GIS-based integrated management system to prevent the disasters that caused by steep slope lands. The integrated management system developed in this study consists of surface information input modules, realtime DB liaison modules of integrated underground information, V-world background map-based GIS, integrated management system for steep slope information user modules, realtime liaison interface modules designed for utilizing steep slope information. Also, tests about stability of data storage, system stability and consistency of processing speed were performed.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5231-5235
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• 2013

Objective: NF-E2-related factor 2 (Nrf2) is activated in several human malignancies. However, the role of Nrf2 in gastric cancer (GC) remains incompletely understood. In this study, we therefore analyzed associations of Nrf2 expression status with clinical features and chemotherapeutic resistance in GC. Materials and Methods: A total of 186 samples from GC patients who underwent gastrectomy were used for prognostic assessment. A further 142 samples from GC cases who received first-line combination chemotherapy were applied for investigation of chemoresistance. The Nrf2 expression was evaluated by immunohistochemistry in GC samples, and its relationship with clinicopathological parameters and chemotherapy sensitivity was analyzed. The effect of Nrf2 gene silencing on chemotherapy resistance was also examined by cell viability assay in vivo. Results: Of the 186 patients with GC, 104/186 (55.9%) showed high expression for Nrf2. The overexpression of Nrf2 was an independent predictor of overall survival [OS, hazard ratio (HR) 3.9; P=0.011] and disease-free survival (DFS, HR 4.3; P=0.002). The gene silencing of Nrf2 reduced resistance to cell death induced by 5-FU in GC cell lines. Conclusion: Our data show that Nrf2 is an independent prognostic factor in GC. Furthermore, Nrf2 confers resistance to chemotherapeutic drug 5-FU in GC cells. Taken together, Nrf2 is a potential prognostic marker and predictive for 5-FU resistance in GC.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.38-50
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• 2008

The site-specific seismic responses and corresponding seismic hazards are influenced mainly by the subsurface geologic and geotechnical dynamic characteristics. To estimate reliably the seismic responses in this study, a geotechnical information system (GTIS) within GIS framework was developed by introducing new concepts, which consist of the extended area containing the study area and the additional site visit for acquiring surface geo-knowledge data. The GIS-based GTIS was built for Gyeongju area, which has records of abundant historical seismic hazards reflecting the high potential of future earthquakes. At the study area, Gyeongju, intensive site investigations and pre-existing geotechnical data collections were performed and the site visits were additionally carried out for assessing geotechnical characteristics and shear wave velocity ($V_S$) representing dynamic property. Within the GTIS for Gyeongju area, the spatially distributed geotechnical layers and $V_S$ in the entire study area were reliably predicted from the site investigation data using the geostatistical kriging method. Based on the spatial geotechnical layers and $V_S$ predicted within the GTIS, a seismic zoning map on site period ($T_G$) from which the site-specific seismic responses according to the site effects can be estimated was created across the study area of Gyeongju. The spatial $T_G$ map at Gyeongju indicated seismic vulnerability of two- to five-storied buildings. In this study, the seismic zonation based on $T_G$ within the GIS-based GTIS was presented as regional efficient strategy for seismic hazard prediction and mitigation.

• Journal of Gastric Cancer
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• v.16 no.2
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• pp.105-110
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• 2016

Purpose: In the Adjuvant Chemoradiotherapy in Stomach Tumors (ARTIST) trial, we investigated whether chemoradiotherapy after D2 gastrectomy reduces the rate of recurrence. Recently, the ratio of metastatic lymph nodes to examined lymph nodes (N ratio) has been proposed as an independent prognostic factor in gastric cancer (GC). The aim of this study was to investigate the relationship between the metastatic N ratio and prognosis of GC after curative D2 surgery. Materials and Methods: We retrospectively reviewed the data of 458 ARTIST patients who underwent D2 gastrectomy followed by adjuvant chemotherapy (XP, n=228) or chemoradiotherapy (XPRT, n=230). The disease-free survival (DFS) rates of patients were used to evaluate the influence of N ratio on the treatment outcome. To achieve this, 4 different N ratio categories (0%, 1%~9%, 10%~25%, and >25%) were compared on the basis of their influence on the treatment outcome. Results: On multivariate analysis, the N ratio remained an independent prognostic factor for DFS. The hazard ratios (HRs) for the N ratio categories of 0%, 1%~9%, 10%~25%, and >25% were 1, 1.061, 1.202, and 3.571, respectively. In patients having N ratio >25%, the 5-year DFS rates were 55% and 28% for the XPRT and XP arms, respectively (HR, 0.527; 95% confidence interval, 0.307~0.904; P=0.020). Conclusions: In patients with curatively resected GC, the N ratio was independently associated with DFS. Although this finding warrants further investigation in future prospective studies, the benefit of chemoradiotherapy for D2 resected GC appears to be more beneficial in cancers having N ratios >25%.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.553-564
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• 2021

This study analyzed the the risk of halogen lamp for pigsty heating and its fire prevention. Halogen lamps are used for keeping warm in pen because of their excellent economy and convenience. However, there is a high risk of fire due to poor safety management and exposure to animal movements. In fact, after exploring old pigsty and cattle shed, it was easy to confirm that they were exposed to fire risks. We noted this point and studied the possibility of fire by experiment due to combustible contact with halogen lamp and carelessness in use. The experiment was conducted under conditions similar to the actual use environment. After installing halogen lamps to the height used in actual pen, the temperature change was observed with infrared camera with straw, sawdust and rice husks on the floor. And assuming abnormal conditions, the experiment was also conducted under conditions the lamp dropped on the floor or combustible material came into contact with the glass tube inside the lamp. If halogen lamps were used in normal condition, there was no risk of fire. However, in abnormal use environments, smoke comes out or even ignited. Even if it is convenient for use or highly utilized, high risk of fire will require setting up fire prevention measures or regulation of use. Through in-depth fire investigation and research, we should promote the risk of fire and make efforts to prevent fire to minimize human life and property damage.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.47-60
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• 2021

Hydrogen is a next-generation energy source, and according to the roadmap for activating the hydrogen economy, it is expected that industries to stably produce, store, and transport of hydrogen as well as the supply of hydrogen fuel cell vehicles will be made rapidly. Accordingly, safety measures for accidents of hydrogen vehicles in confined spaces such as tunnels are required. In this study, as part of a study to ensure the safety of hydrogen fuel cell vehicles in road tunnels, a basic investigation and research on the risk of fire and explosion due to gas leakage and hydrogen tank rupture among various hazards caused by hydrogen fuel cell vehicle accidents in tunnels was conducted. The following results were obtained. In the event of hydrogen fuel cell vehicle accidents, the gas release rate depends on the orifice diameter of TPRD, and when the gas is ignited, the maximum heat release rate reaches 3.22~51.36 MW (orifice diameter: 1~4 mm) depending on the orifice diameter but the duration times are short. Therefore, it was analyzed that there was little increase in risk due to fire. As the overpressure of the gas explosion was calculated by the equivalent TNT method, in the case of yield of VCE of 0.2 is applied, the safety threshold distance is analyzed to be about 35 m, and number of the equivalent fatalities are conservatively predicted to reach tens of people.