• Structural Monitoring and Maintenance
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• v.7 no.3
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• pp.261-281
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• 2020

Civil structures may experience progressive deterioration and damage under environmental and operational conditions over their service life. Finite element (FE) model updating method is one of the most important approaches for damage identification in structures due to its capabilities in structural health monitoring. Although various damage detection approaches have been investigated on structures, there are limited studies on large-sized space structures. Thus, this paper aims to investigate the applicability and efficiency of sensitivity-based FE model updating framework for damage identification in large space structures from a distinct point of view. This framework facilitates modeling and model updating in large and geometric complicated space structures. Considering sensitivity-based FE model updating and vibration measurements, the discrepancy between acceleration response data in real damaged structure and hypothetical damaged structure have been minimized through adjusting the updating parameters. The feasibility and efficiency of the above-mentioned approach for damage identification has finally been demonstrated with two numerical examples: a flat double layer grid and a double layer diamatic dome. According to the results, this method can detect, localize, and quantify damages in large-scaled space structures very accurately which is robust to noisy data. Also, requiring a remarkably small number of iterations to converge, typically less than four, demonstrates the computational efficiency of this method.

• Proceedings of the KSRS Conference
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• v.1
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• pp.402-405
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• 2006

Radiometric calibration of optical image data is necessary to convert raw digital number (DN) value of each pixel into a physically meaningful measurement (radiance). To extract rather quantitative information regarding biophysical characteristics of the earth surface materials, radiometric calibration is often essential procedure. A sensor detects the radiation of sunlight interacted atmospheric constituents. Therefore, the amount of the energy reaching at the sensor is quite different from the initial amount reflected from the surface. To achieve the target reflectance after atmospheric correct, an initial step is to convert DN value to at-sensor radiance. A linear model, the simplest radiometric model, is applied to averaged spectral radiance for this conversion. This study purposes to analyze the sensitivity of several factors affecting on radiance for carrying out absolute radiometric calibration of panchromatic images from KOMPSAT2 launched at July, 2006. MODTRAN is used to calculate radiance at sensor and reflectance of target is measured by a portable spectro-radiometer at the same time the satellite is passing the target for the radiometric calibration. As using different contents of materials composing of atmosphere, the differences of radiance are investigated. Because the spectral sensitivity of panchromatic images of KOMPSAT2 ranges from 500 to 900 nm, the materials causing scattering in visible range are mainly considered to analyze the sensitivity. According to the verified sensitivity, direct measurement can be recommenced for absolute radiometric calibration.

• Journal of the Korea Institute of Building Construction
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• v.9 no.1
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• pp.123-129
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• 2009

The global financial crisis resulting from sub-prime mortgage crisis in the United States, beginning in 2007, has had dealt a blow to domestic economy. The economic downturn, coupled with a large number of apartments remaining unsold has resulted in contracted investment sentiment of the builders. Thus it's difficult to even implement the business, unless the investment project is thoroughly verified as well as the accurate profitability is granted. Viewing the current situation, forecasting and evaluating the business profitability is more than important today. The study was planned to identify the factors influencing the business success and to evaluate the sensitivity, relative risk of each factor was measured, and the scope of the study was limited to the commercial buildings among other buildings except apartment buildings. Hence, the study was aimed to analyze the factors affecting the business and the sensitivity so as to be able to systematically materialize the risk management of the commercial buildings. The outcome of the study is expected to serve the useful data in analyzing the business profitability and implementing the investment projects as well.

• Journal of Preventive Medicine and Public Health
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• v.22 no.1 s.25
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• pp.45-50
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• 1989

The purpose of this study was to select the manageable diseases which are prevalent in Korea for periodic health examinations and to evaluate the sensitivity and specificity of periodic health examination in detecting these diseases. The data was derived from reimbursement data of the Korea Medical Insurance Corporation over a two year period (April 15, 1986 to April 14,1988) and interviews with Yonsei Medical School professors. This study demonstrated that: 1. The manageable diseases which were selected for periodic health examinations are pulmonary tuberculosis, viral hepatitis, diabetes mellitus, syphilis groups, essential hypertension, renal disease groups, and iron deficiency anemia. 2. The sensitivity of the health screening for each disease was as follows: pulmonary tuberculosis 51.5%, viral hepatitis 60.3%, diabetes mellitus 64.7%, syphilis groups 63.3%, essential hypertension 49.9%, renal disease groups 44.0%, and iron deficiency anemia 80.9%. We conclude that peiodic health esaminations should focus on the manageable diseases that we have defined. The number of items in periodic health screening tests and hospital quality control should be increased for the diseases with a demonstrated low sensitivity.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.3
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• pp.741-750
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• 1995

The turbulent buoyancy-driven flow in 2-dimensional enclosed cavities heated from the vertical side is numerically calculated for both cases of a Rayleigh number of 5*10$^{10}$ for air and 2.5*10$^{10}$ for water. Three different turbulence models are considered : standard k-.epsilon. model of Ozoe and low-Reynolds-number model of Lam and Bremhorst, and another low-Reynolds-number model of Davidson. The results indicate that the use of low-Reynolds number models is recommended for the indoor airflow computation, and the results from Davidson model are reasonably close to the reported experimental data. A sensitivity study shows that the amounts of wall-heat transfer and the velocity profiles with the Lam and Bremhorst model largely depend on the choice of the wall function for .epsilon..

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.4
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• pp.455-465
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• 2015

Purpose: This study aimed to explore human rights sensitivity and the perception of patients' rights among nursing students. For the study, 253 nursing students from K and D universities located in Daegu and the Gyeongbuk region were asked to participate. Methods: Data were analyzed using IBM SPSS Statistics 20.0; in addition, descriptive statistics, a t-test, and a one-way ANOVA were used. Results: The average human rights sensitivity score was 2.40 out of 5 points. Human rights sensitivity was significantly different in education experiences in regards to human rights after getting into nursing school and in nursing courses, as well as experiences of clinical practice. Among the six episodes that measured human rights sensitivity, nursing students reported the highest score on the right to the pursuit of happiness of older people and the lowest score was reported on the right to privacy. The average score of patients' rights perception was 4.53 out of 5 points. In particular, nursing students considered the right to enjoy human worth/dignity and the right to equality to be the most important of patients' rights. Patients' rights perception, in general, was significantly different depending on the number of family members. Conclusion: It is needed to develop an effective nursing curriculum in order to improve nursing students' human rights sensitivity and foster positive perceptions regarding patients' rights.

• Korean Journal of Veterinary Research
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• v.50 no.1
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• pp.43-48
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• 2010

Animal disease surveillance system, defined as the continuous investigation of a given population to detect the occurrence of disease or infection for control purposes, has been key roles to assess the health status of an animal population and, more recently, in international trade of animal and animal products with regard to risk assessment. Especially, for a system aiming to determine whether or not a disease is present in a population sensitivity of the system should be maintained high enough not to miss an infected animal. Therefore, when planning the implementation of surveillance system a number of factors that affecting surveillance sensitivity should be taken into account. Of these parameters sample size is of important, and different approaches are used to calculate sample size, usually depending on the objective of surveillance systems. The purpose of this study was to evaluate the sensitivity of the current national serological surveillance programs for four selected bovine diseases assuming a specified sampling plan, to examine factors affecting the probability of detection, and to provide sample sizes required for achieving surveillance goal of detecting at least an infection in a given population. Our results showed that, for example, detecting low level of prevalence (0.2% for bovine tuberculosis) requires selection of all animals per typical Korean cattle farm (n = 17), and thus risk-based target surveillance for high risk groups can be an alternative strategy to increase sensitivity while not increasing overall sampling efforts. The minimum sample size required for detecting at least one positive animal was sharply increased as the disease prevalence is low. More importantly, high reliability of prevalence estimation was expected with increased sampling fraction even when zero-infected animal was identified. The effect of sample size is also discussed in terms of the maximum prevalence when zero-infected animals were identified and on the probability of failure to detect an infection. We suggest that for many serological surveillance systems, diagnostic performance of the testing method, sample size, prevalence, population size, and statistical confidence need to be considered to correctly interpret results of the system.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.387-392
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• 2011

Enzymes are being used in various fields due to their unique property of substrate specificity. Enzyme-linked immunosorbent assay(ELISA) has enabled the detection of various antigens by reporting the binding event of antigen and antibody via enzyme-catalyzed reaction. However, the sensitivity improvement of conventional ELISA has been limited because only one enzyme molecule is conjugated to one molecule of antibody. To overcome this limitation and further improve the sensitivity of ELISA, there have been efforts to increase the number ratio of enzymes to antibody. Recently, the nanobiocatalytic approaches, with their successful enzyme stabilization, improved the performance stability as well as sensitivity in a modified protocol of ELISA. The present paper introduces the basic principle of ELISA, and the recent efforts to improve sensitivity and performance stability of ELISA by using the nanobiocatalytic approaches.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.571-576
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• 2001

Hydroforming, the new production technology, has been used to manufacture many parts of vehicle in the recent auto industry. When Hydroforming is applied, it is possible to make parts simplification and flexible alteration of section shape in many advantages such as weight reduction, number of parts reduction or performance improvement. This research into shape optimization which reduces number of parts and weight maintaining performance was achieved. In this paper, the COWL CROSS BAA and MT'g BAKT parts of A car STEERING support SYSTEM was introduced by using Hydroforming.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.618-627
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• 2017

Recently, the number of cases of child abuse has been increasing and, consequently, the social interest in this issue is increasing. The purpose of this study is to examine the relationship between child abuse, rejection sensitivity and emotional regulation and to identify the mediating effects of rejection sensitivity in the relationship between child abuse and emotional regulation. For this purpose, a survey on child abuse, rejection sensitivity and emotional regulation was administered to 217 elementary school students in the fourth, fifth and sixth grades, who had been reported as victims of child abuse or managed as suspected child abuse victims in the Seoul, Gyeonggi, Gangwon, Chungcheong, and Gyeongsang regions. The data was analyzed using structural equation modelling and bootstrapping. The findings showed that child abuse was significantly negatively correlated with emotional regulation, but positively correlated with rejection sensitivity. Emotional regulation was significantly negatively correlated with rejection sensitivity. Second, the structural equation analysis also revealed that rejection sensitivity fully mediated the relationship between child abuse and emotional regulation. This means that child abuse has an indirect effect on emotional regulation through rejection sensitivity. Therefore, when counseling abused children with emotional regulation problems, it is important for the counselors to include interventions designed to lower their rejection sensitivity.