• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.3
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• pp.73-87
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• 2023

Furnishing traffic safety information can contribute to providing hazard warnings to drivers, thereby avoiding crashes. A smart road lighting platform that instantly recognizes road conditions using various sensors and provides appropriate traffic safety information has therefore been developed. This study analyzes the short-term traffic safety improvement effects of the smart road lighting's tunnel traffic safety information service using surrogate safety measures (SSM). Individual driving behavior was investigated by applying the vehicle trajectory data collected with RADAR in the Anin Avalanche 1 and 2 tunnel sections in Gangneung. Comparing accumulated speeding, speed variation, time-to-collision, and deceleration rate to avoid the crash before and after providing traffic safety information, all SSMs showed significant improvement, indicating that the tunnel traffic safety information service is beneficial in improving traffic safety. Analyzing potential crash risk in the subdivided tunnel and access road sections revealed that providing traffic safety information reduced the probability of traffic accidents in most segments. The results of this study will be valuable for analyzing the short-term quantitative effects of traffic safety information services.

• Journal of the Korean Society of Radiology
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• v.7 no.1
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• pp.37-44
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• 2013

In study suggested clinical availability to shoulder forced traction method in term of quality of image, the patient's convenience and stability, according to whether to use of shoulder forced traction bend using computed tomography(CT) that X-ray calibration and various mathematic calibration algorithm application can be applied by AEC. To achieve this, 79 patients is complaining of cervical pain oriented that shoulder forced traction bend use the before and after acquires lateral projection scout image and transverse image. transverse image of a fixed size in concern field of pixel and figure the average HU value compare that quantitative analysis. Artifact and pixel and resolution to qualitative clinical estimation image analysis. the patient feel inconvenience degree that self-diagnosis survey that estimate. As a result, lateral projection scout image if you used shoulder forced traction bend for the depicted has been an increase in the number of a cervical vertebrae. transverse image concern field shoulder forced traction bend use the before and after for pixel and the average HU-value changes was judged to be almost irrelevant. Artifact and resolution and contrast, in qualitative analysis of the results relating the observer to the unusual result. So, the patients of 82.27% complained discomfort that use of shoulder forced traction bend in self-diagnosis survey. No merit of medical image by using of bend from result was analyzed quality of image to quantitative and qualitative method judged. Nowadays, CT is supplied possible revision of quality of radiation by reduction of slice and automatic exposure controller, etc and application of preconditioning filter process due to various mathematic revision algorithm. So, image noise by beam hardening artifact should not be a problem. shoulder forced traction bend of use no longer judged clinically availability because have not influence of image quality and give discomfort, have extra dangerousness.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.64-73
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• 2015

The theft of construction equipments and materials at construction sites is one of the risk factors that may affect to the productivity as well as the progress of the project. However, managers of the construction site have paid little attention to the security measure, therefore the theft loss at construction sites has been occurred repeatedly every year. In this study the situation analysis has been carried out for the present condition of theft loss of construction equipments and materials as well as its prevention measure based on the questionnaire survey targeting field managers, experienced theft loss at the site, as a part of base study to set up a security measure of construction sites. The main content of this study is analyzing characteristics of theft loss and the degree of impact and risk by it at construction sites, then reviewing the direction of the prevention plan establishment for the future through the analysis of the importance and utilization level of prevention measures. The result of this study would give an opportunity to create an awareness against the theft loss at construction sites as well as can be utilized as a basic survey for the systematic development of concerned prevention measures.

• Journal of the Korean Geotechnical Society
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• v.31 no.8
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• pp.51-62
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• 2015

It is not possible to provide resonable evidence for embankment (or dam) overtopping in geotechnical engineering, and conventional analysis by hydrologic design has not provided the evidence for the overflow. However, hydrologic design analysis using Copula function demonstrates the possibility that dam overflow occurs when estimating rainfall probability with rainfall data for 40 years based on fluctuating water level of a dam. Hydrologic dam risk analysis depends on complex hydrologic analyses in that probabilistic relationship needs to be established to quantify various uncertainties associated with modeling process and inputs. The systematic approaches to uncertainty analysis for hydrologic risk analysis have not been addressed yet. In this paper, the initial level of a dam for stability of a dam is generally determined by normal pool level or limiting the level of the flood, but overflow of probability and instability of a dam depend on the sensitivity analysis of the initial level of a dam. In order to estimate the initial level, Copula function and HEC-5 rainfall-runoff model are used to estimate posterior distributions of the model parameters. For geotechnical engineering, slope stability analysis was performed to investigate the difference between rapid drawdown and overtopping of a dam. As a result, the slope instability in overtopping of a dam was more dangerous than that of rapid drawdown condition.

• Neonatal Medicine
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• v.17 no.2
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• pp.201-206
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• 2010

Purpose: Recently, after patent ductus arteriosus (PDA) ligation in preterm infants, unexplained hemodynamic instabilities are reported. To determine the incidence, risk factors and clinical manifestations of hemodynamic instability after PDA ligation in very low birth weight (VLBW) infants. Methods: This retrospective multicenter study enrolled 18 VLBW infants who underwent PDA ligation from January 2002 to February 2008. Hemodynamic instability defined as unexplained cardiopulmonary dysfunction with increased dependency on mechanical ventilation and decreased blood pressure. Results: The mean gestational age and birth weight (BW) of all infants were $27^{+6}{\pm}1^{+6}$ weeks and 951${\pm}$245 g. Hemodynamic instability group (HI) included seven infants (39%) and hemodynamic stability group (HS) included 11 infants (61%). Compared to HS, HI had lower BW (1,033${\pm}$285 g vs. 821${\pm}$126 g, P=0.048) and weight on operation day (1,195${\pm}$404 g vs. 893${\pm}$151 g, P=0.042), longer hospital days (105${\pm}$29 vs. 141${\pm}$39, P=0.038), more severe bronchopulmonary dysplasia (BPD), (no/mild/moderate/severe, 2/5/2/2 vs. 0/1/2/4, P=0.038) and higher preoperative $FiO_2$ (0.29${\pm}$0.06 vs. 0.38${\pm}$0.09, P=0.02). One case of mortality due to sepsis, which was not associated with ligation, was observed among HS. Conclusion: The incidence of hemodynamic instability after PDA ligation in VLBW infants was 39%. Low BW, low weight on operation day and preoperative high $FiO_2$ might be risk factors of hemodynamic instability after PDA ligation in VLBW infants. The hemodynamic instability could increase the severity of BPD and hospital days.

• Journal of Conservation Science
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• v.28 no.2
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• pp.153-164
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• 2012

The major petroglyphs of Bangudae site were composed mainly of hornfelsed shale. Surface of the rock was formed weathering layer (average porosity 25%) that discriminated mineral and chemical composition against fresh rock (average porosity 0.4%). The lost area of major petroglyphs in the past up images carved to the present was calculated about 23.8%. And occurrence area of exfoliation indicated 1.2% of the whole petroglyphs. As a result of the chromaticity analysis, color of the major petroglyphs was changed brighter and yellower than fresh rock by chemical and biological weathering factors. Average ultrasonic velocity of petroglyphs was measured 2,865m/s. This result indicated that ultrasonic velocity decreased especially bottom of petroglyphs than measured result in 2003 year. The results of the evaluation for slope stability, it identified the possibility of toppling, planar and wedge failure in host rock. The 3D image analysis and modeling data of the cavern obtained for structural reinforcement.

• Journal of Chest Surgery
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• v.38 no.5 s.250
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• pp.377-381
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• 2005

Background: Extra-anatomic bypass was performed in the patient who could not use anatomic bypass due to many causes. The purpose of this study is to evaluate the efficacy of extra-anatomic bypass surgery. Material and Method: We reviewed 31 patients who underwent extra-anatomic bypass surgery at Pusan national university hospital. We analysed the combined diseases, etiologic diseases, symptoms, patency rate and the factors affecting patency rate retrospectively. Result: There were 26 cases of femoro-femoral bypass and 5 cases of axillo-bifemoral bypass among 31 patients. The mean age was 70.23 years. Combined disease were hypertension, hyperlipidemia, and ischemic heart disease in order of frequency. The indications for surgery were disabled claudication, tissue necrosis, rest pain, and a cute ischemia. We analysed the ages, smoking history, hypertension, ischemic heart disease, severity of limb ischemia, and hyperlipidemia as factors affecting patency rate. We could not find any statistical differences between these factors. The primary graft patency rates were $73.65\%$ one year, $73.65\%$ two year, and $65.46\%$ three year respectively according to the Kaplan-Meier method. Conclusion: Nevertheless extra-anatomic bypass has a relatively low patency rate, it has good merits that is less dangerous, simple and easy re-do surgery compared to anatomic bypass. We think that extra-anatomic bypass is one of the good treatment modalities for the high risk vascular patients.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.81-90
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• 2009

The safety management of a road network comprises four basic inter-related components：identification of sites(black spot) requiring safety investigation, diagnosis of safety problems, selection of feasible treatments for potential treatment candidates, and prioritization of treatments given limited budgets(Persaud, 2001). Identification process of selecting black spot is very important for efficient investigation of sites. In this study, the accident prediction model for EB method was developed by using accident data and geometric conditions of black spots selected from four-leg signalized intersections in In-cheon City for three years (2004-2006). In addition, by comparing the rank nomination technique using EB method to that by using accident counts, we managed to show the problems which the existing method have and the necessity for developing rational prediction model. As a result, in terms of total number of accidents, both the counts predicted by existing non-linear regression model and that by EB method have high good of fitness, but EB method, considering both the accident counts by sites and total number of accident, has better good of fitness than non-linear poison model. According to the result of the comparison of ranks nominated for treatment between two methods, the rank for treatment of almost sites does not change but SeoHae intersection and a few other intersections have significant changes in their rank. This shows that, with the technique proposed in the study, the RTM problem caused by using real accident counts can be overcome.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.259-268
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• 2019

Dengue virus is a typical mosquito-borne virus, and the half of the world's population is exposed to infection. Dengue virus causes relatively mild symptoms such as dengue fever. However, when not treated properly, it is known to cause severe symptoms such as dengue hemorrhagic fever and dengue shock syndrome with a mortality rate of over 20%. Development of dengue virus detection technology is very important because it is reported that early diagnosis of dengue fever can lower the mortality rate to less than 1%. In this study, patent search related to dengue virus detection technology was conducted in Korea, USA, Europe, Japan, and China. The quantitative analysis of 69 validated patents from the searched patents was conducted by country, year, and patent holder. In addition, in-depth analysis was carried out by classifying into three categories: molecular diagnostics, immuno-diagnostics, and cell culture-based diagnostics from all validated patents. From these results, we analyzed the patent trend related to dengue virus detection and dengue fever diagnosis technology and discussed the features and limitations of molecular diagnostics and immuno-diagnostics at present level. Furthermore, we discussed the direction of technology development and future prospects to overcome limitations.

• Tuberculosis and Respiratory Diseases
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• v.61 no.1
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• pp.34-40
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• 2006

Background: Extubation failure was associated with poor prognosis and high hospital mortality. Cuff leak test (CLT) has been proposed as a relatively simple method for detecting laryngeal obstruction that predispose toward postextubation stridor (PES) and reintubation. We examined the risk factors of extubation failure and evaluated the usefulness and limitation of CLT for predicting PES and reintubation. Methods: Thirty-four consecutive patients intubated more than 24 hours were examined. The subjects were evaluated daily for extubation readiness, and CLT was performed prior to extubation. Several parameters in the extubation success and failure group were compared. The accuracy and limitation of CLT were evaluated after choosing the thresholds values of the cuff leak volume (CLV) and percentage (CLP). Results: Of the 34 patients studied, 6 (17.6%) developed extubation failure and 3 (8.8%) were accompanied by PES. The patients who had extubation failure were more likely to have a longer duration of intubation and more severe illness. The patients who developed PES had a smaller cuff leak than the others: according to the CLV ($22.5{\pm}23.8$ vs $233.3{\pm}147.1ml$, p=0.020) or CLP ($6.2{\pm}7.3$ vs $44.3{\pm}24.7%$, p=0.013). The best cut off values for the CLV and CLP were 50ml and 14.7%, respectively. The sensitivity, negative predictive value, and specificity of CLT were relatively high, but the positive predictive value was low. Conclusion: The likelihood of developing extubation failure increases with increasing severity of illness and duration of intubation. A low CLV or CLP (<50ml or 14.7%) is useful in identifying patients at risk of PES, but the CLT is not an absolute predictor and should not be used an indicator for delaying extubation.