• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.206-209
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• 2004

Mechanical behavior of a fuel stack was studied using an orthotropic material model. The fuel stack is essentially composed of a bipolar plate (BP), a gasket, an end plate, a membrane electrolyte assembly (MEA), and a gas diffusion layer (GDL). Each component is fastened with a suitable pressure. It is important to maintain a suitable contact pressure distribution of BP, because it influences the power efficiency of the fuel cell stack. When it is exposed to high temperature, its behavior must be stable. Hence, we performed stress analysis at high temperature as well as at room temperature. At high temperature, the contact pressure distribution becomes poor. Many patents have shown that using an elastomer can overcome this phenomena. Its effect was also studied. By using an elastomer, we found a good contact pressure distribution at high temperature as well as at room temperature.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.749-755
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• 2023

A new approximation method was proposed for treating the non-resonant spatial self-shielding effects of double heterogeneous region such as the double heterogeneous effect of VHTR fuel compact in the thermal energy range and that of BP compact with BISO. The method was developed based on the effective homogenization method and a spherical unit cell model with explicit coated layers and a matrix layer. The self-shielding factor was derived from the relation between the collision probabilities for a double heterogeneous compact and the effective cross section for the homogenized compact. First, the collision probabilities and transmission probabilities for all layers of the spherical model were calculated using conventional collision probability solver. Then, the effective cross section for the homogenized sphere cell representing the homogenized compact was obtained from the transmission probability calculated using the probability density function of a chord length. The verification calculations revealed that the proposed method can predict the self-shielding factor with a maximum error of 2.3% and the double heterogeneous effect with a maximum error of 200 pcm in the typical VHTR problems with various packing fractions and BP compact sizes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2819-2822
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• 2012

Objective: To assess induction effects of Chlamydia pneumoniae (Cpn) on lung cancer in rats. Methods: A lung cancer animal model was developed through repeated intratracheal injection of Cpn (TW-183) into the lungs of rats, with or without exposure to benzo(a)pyrene (Bp). Cpn antibodies (Cpn-IgA, -IgG, and -IgM) in serum were measured by microimmunofluorescence. Cpn-DNA or Cpn-Ag of rat lung cancer was detected through polymerase chain reaction or enzyme-linked immunosorbent assay. Results: The prevalence of Cpn infection was 72.9% (35/48) in the Cpn group and 76.7% (33/43) in the Cpn plus benzo(a)pyrene (Bp) group, with incidences of lung carcinomas in the two groups of 14.6% (7/48) and 44.2% (19/43), respectively (P-values 0.001 and <0.000 compared with normal controls). Conclusions: A rat model of lung carcinoma induced by Cpn infection was successfully established in the laboratory for future studies on the treatment, prevention, and mechanisms of the disease.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.301-312
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• 2017

Quality evaluation and control represent increasingly important concerns for construction quality management. There is an evident need for a standard data model to be used as the basis for computer-aided quality management. This study focuses on how to realize evaluation of construction quality based on BIM and database technology. In this paper, the reinforced concrete main structure is taken as an example, and the BP neural network evaluation model is established by inquiring current construction quality acceptance specification and evaluation standard. Furthermore, IFC standard is extended to integrate quality evaluation information and realize the mapping of evaluation information in BIM model, contributing to the visualization and transfer sharing of evaluation information. Furthermore, the conceptual entity model is designed to build quality evaluation database, and this paper select MySQL workbench system to achieve the establishment of the database. This study is organized to realize the requirement of visualization and data integration on construction quality evaluation which makes it more effective, convenient, intuitive, easy to find quality problems and provide more comprehensive and reliable data for the quality management of construction enterprises and official construction administratiors.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.513-520
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• 2000

Objectives : To estimate the prevalence of hypertension, rates of awareness, treatment modalities, and control of hypertension, and also to identify factors in rural Korea that are related to these aspects of hypertension. Methods : A cross-sectional survey, including blood pressure(BP) measurements and interviews, investigating the variables in the health belief model was peformed from August to November, 1999 on 1,426 (79.4%) study subjects out of 1,797 registered residents over 30 years old in Ibansong-Myun, Chinju City. A second survey was peformed from January to March, 2000 on 376 (80.0%) subjects out of 470 hypertensive (or suspected hypertensive) subjects found in the first survey. Two BP readings were taken in each survey using a standard mercury sphygmomanometer. Hypertension was defined as either a BP reading $\geq$ 140/90 mmHg in both surveys, or as subjects on oral hypertensive medication. Results : Estimated hypertension prevalence was 24.9% for men, and 30.4% for women. Rates of hypertension awareness, treatment (the regular use of oral hypertensives), and control (reduction of BP to <140/90 mmHg) were 52.5%, 34.4%, and 12.9%, respectively. The factors related to lower hypertension awareness in the logistic regression analysis were male gender, farming occupation, and higher perceived barrier to medical treatment (those for whom visiting health professionals is a burden). Conclusions : To improve the low awareness, treatment, and control of hypertension, a more active and out-reaching hypertension control program, including routine BP measurements for every visitor to primary care facilities, is needed in rural Korea.

• Journal of Acupuncture Research
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• v.39 no.2
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• pp.122-133
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• 2022

Background: This study was designed to statistically analyze the data of patients who had Bell's palsy (BP) who visited a Korean Medicine hospital in the last 3 years to determine the tendency or characteristics of their visit. Methods: This study retrospectively analyzed the medical records of 816 patients. Based on the data collected through medical records demographics, condition/disease, and therapeutic characteristics of the patients were analyzed using IBM SPSS Version 23.0. Results: Patients in their teens or younger, and 50s or older had a higher frequency of inpatient treatment, and 20s to 40s had a higher rate of outpatient treatment. The proportion of men who received steroid combination treatment was higher than women. The number of patients with BP, and the total treatment period of the patients has decreased every year. The total treatment period was shorter in the steroid group than the Korean medicine alone group. Inpatients were more likely to receive steroid combination therapy than outpatients. The proportion of patients who received steroid combination therapy was higher than patients with recurrence of BP. Patients with hypertension or diabetes had a higher rate of hospitalization and received more treatments than patients without the condition/disease. Conclusion: Visit characteristics and treatment methods preferred by patients with BP were identified. This research may help to establish a treatment model for BP in Korean Medicine institutions in the future.

• Journal of Korea Port Economic Association
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• v.30 no.1
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• pp.143-157
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• 2014

Most metropolitan shippers (MS) have used trans pacific route (TPR) or Asia-Europe route (AEP) through Busan port (BP). If Incheon new port (INP) sets up the deep water-depths under -16m, however, there might be a change in MS's port choice behavior (PCB). In this respect, the aim of this paper is to estimate an INP's allotment rate for metropolitan cargo using Logit Model (LM) considering changing global shipping and port environment. This paper reviews previous studies related to shippers' PCB then sets up the utility function (UF) including the dummied dependent variable which is comprised of BP and INP, and some independent variables such as the frequency of liner shipping route (TPR), inland transportation fare, and the rate of container terminal service. As a result of LM analysis, BP has 0.6618 and INP has 0,3382.

• ETRI Journal
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• v.35 no.6
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• pp.1105-1114
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• 2013

Owing to the large number of video programs available, a method for accessing preferred videos efficiently through personalized video summaries and clips is needed. The automatic recognition of user states when viewing a video is essential for extracting meaningful video segments. Although there have been many studies on emotion recognition using various user responses, electroencephalogram (EEG)-based research on preference recognition of videos is at its very early stages. This paper proposes classification models based on linear and nonlinear classifiers using EEG features of band power (BP) values and asymmetry scores for four preference classes. As a result, the quadratic-discriminant-analysis-based model using BP features achieves a classification accuracy of 97.39% (${\pm}0.73%$), and the models based on the other nonlinear classifiers using the BP features achieve an accuracy of over 96%, which is superior to that of previous work only for binary preference classification. The result proves that the proposed approach is sufficient for employment in personalized video segmentation with high accuracy and classification power.

• Biomedical Science Letters
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• v.12 no.3
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• pp.191-196
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• 2006

Cardiovascular disease (CVD) risk factors may be acting several decades before CVD becomes manifest. Data from young subjects may be valuable in further elucidating at this issue. We evaluated the association between baPWV (brachial-ankle pulse wave velocity) and cardiovascular risk factors in apparently healthy young adults. A total of 46 male and 91 female adolescents aged $18{\sim}25 years$ were studied. baPWV increased in a dose-responsive manner as the number of metabolic syndrome components. In both gender groups, baPWV was positively correlated with age. In males, waist, circumference total cholesterol, and LDL-cholesterol were positively correlated with baPWV, and in females, blood pressure (BP) was positively correlated with baPWV. Age, gender, mean BP, and Homeostasis model assessment insulin resistance (HOMA-IR) were found to be independent factors associated with baPWV levels. In conclusion, mean BP, age, gender, and HOMA-IR were associated with baPWV in young adults. This result suggests that multiple cardiovascular risk factors may be associated with an increased risk of arterial stiffness in young adults.

• International Journal of Quality Innovation
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• v.3 no.2
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• pp.113-131
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• 2002

The relationships among multi-dimensional data (such as medical examination data) with ambiguity and variation are difficult to explore. The traditional approach to building a data classification system requires the formulation of rules by which the input data can be analyzed. The formulation of such rules is very difficult with large sets of input data. This paper first describes two classification approaches using back-propagation (BP) neural network and Mahalanobis distance (MD) classifier, and then proposes two classification approaches for multi-dimensional feature selection. The first one proposed is a feature selection procedure from the trained back-propagation (BP) neural network. The basic idea of this procedure is to compare the multiplication weights between input and hidden layer and hidden and output layer. In order to simplify the structure, only the multiplication weights of large absolute values are used. The second approach is Mahalanobis-Taguchi system (MTS) originally suggested by Dr. Taguchi. The MTS performs Taguchi's fractional factorial design based on the Mahalanobis distance as a performance metric. We combine the automatic thresholding with MD: it can deal with a reduced model, which is the focus of this paper In this work, two case studies will be used as examples to compare and discuss the complete and reduced models employing BP neural network and MD classifier. The implementation results show that proposed approaches are effective and powerful for the classification.