• Advances in Computational Design
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• 제7권1호
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• pp.81-98
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• 2022

This study presents the application of two indices for the locating of cracks in Reinforced Concrete (RC) structures, as well as the development of their modified forms to overcome limitations. The first index is based on mode shape curvature and the second index is based on the fourth derivative of the mode shape. In order to confirm the indices' effectiveness, both eigenvalues coupled with nonlinear static analyses were carried out and the eigenvectors for two different damage locations and intensities of load were obtained from the finite element model of RC beams. The values of the damage-locating indices derived using both indices were then compared. Generally, the mode shape curvature-based index suffered from insensitivity when attempting to detect the damage location; this also applied to the mode shape fourth derivative-based index at lower modes. However, at higher modes, the mode shape fourth derivative-based index gave an acceptable indication of the damage location. Both the indices showed inconsistencies and anomalies at the supports. This study proposed modification to both indices to overcome identified flaws. The results proved that modified forms exhibited better sensitivity for identifying the damage location. In addition, anomalies at the supports were eliminated.

• 한국콘텐츠학회논문지
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• 제21권5호
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• pp.446-464
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• 2021

본 연구는 청소년들의 스마트폰 사용이 증가됨에 따라 사이버폭력을 예방하기 위한 대안을 모색하기 위하여 청소년의 학교폭력 경험과 사이버폭력의 관계에서 인권감수성과 또래동조성의 다중매개효과를 검증하는데 연구 목적이 있다. 이러한 연구목적을 달성하기 위해 부산 시내에 소재한 교육청 별로 중학교 4곳을 선정하여 중학생 908명을 대상으로 분석하였다. 연구결과는 다음과 같다. 첫째, 학교폭력 경험은 사이버폭력에 영향을 미치는 것으로 나타났다. 둘째, 학교폭력 중 가해경험과 방관경험은 인권 감수성에 영향을 미쳤으나 피해경험은 인권감수성에 영향을 미치지 않았다. 셋째, 학교폭력경험 중 피해경험과 가해경험은 또래동조성에 영향을 미쳤으나 방관경험은 또래동조성에 영향을 미치지 않았다. 넷째, 인권감수성은 사이버폭력에 영향을 미쳤다. 다섯째, 또래동조성은 사이버폭력에 영향을 미쳤다. 여섯째, 인권감수성은 또래동조성에 영향을 미쳤다. 일곱째, 인권감수성 중 방관경험은 방관경험과 사이버폭력을 매개하는 것으로 나타났으나, 피해경험과 가해경험은 인권감수성과 사이버폭력에서 매개효과가 발생하지 않았다. 여덟째, 또래동조성은 피해경험, 가해경험 모두 사이버폭력을 매개하는 것으로 나타났으나 방관경험과 사이버폭력 사이에서는 매개효과 없는 것으로 나타났다. 아홉째, 인권감수성과 또래조성은 방관경험과 사이버폭력 관계를 순차적으로 매개하는 것으로 나타났다. 그러나 인권감수성과 또래조성은 피해경험과 가해경험 사이에서 사이버폭력을 순차적으로 매개하지 않았다. 본 연구의 시사점은 청소년의 학교폭력 피해경험, 가해경험, 방관경험이 사이버폭력에 미치는 효과와 인권감수성과 또래동조성의 다중매개효과를 검증하여 청소년의 학교폭력 경험이 사이버폭력에 미치는 영향에서 피해경험, 가해경험, 방관경험을 가진 청소년이 사이버폭력의 중복경험을 하지 않기 위한 사회복지 역할을 모색하고, 사이버폭력 예방을 위한 실천적, 정책적 방안을 제시하였다는데 의의가 있다.

• 한국소음진동공학회논문집
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• 제21권4호
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• pp.333-338
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• 2011

This paper describes the design process of floor damping material optimization to reduce structure borne noise. This process uses finite element analysis(FEA) along with experimental techniques to complement each other. The objective of this approach was to develop an optimized damping material application layout and thickness at the initial design stage. The first step is to find the sensitivity areas of vehicle body without damping material applied using FEA. In order to determine the high vibration areas of the floor panel, the velocity was measured using a scanning laser vibrometer from 20 Hz to 300 Hz. To excite the floor panel vibration, shaker was placed at the front suspension attachment point. The second step is the optimization process to determine the light weight solution of damping material. The design guideline of damping material was suggested that the lightweight solution was verified using test result of road noise. Design engineer could efficiently decide the design variable of damping material using parameter analysis results in early design stage.

• 대한지구과학교육학회지
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• 제6권1호
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• pp.60-68
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• 2013

The aim of the study is determined to find out how elementary science localization teaching strategy would influence environmental perception of students. In order to fulfill the research purpose, a total of 51 fifth graders from two classes in M Elementary School in U City were divided into a 26 of experimental group and a 25 of comparative group. The study was carried out from September to November of 2012. For the experimental group, an elementary science localization classes were conducted while for the comparative group, a general science classes were performed. The results of the research are presented as follows. First, it was learned that the experimental group with the elementary science localization class would have a significantly and statistically high environmental sensitivity comparing to that of the comparative group. That proves the elementary science localization class's being efficient at improving the students' environmental sensitivity. Second, the experimental group with the elementary science localization class turned out to have a significantly and statistically strong will to protect the environment than the comparative group would do. Such finding says that the elementary science localization class is helpful to enhance the students' will to preserve the environment. In conclusion, the study came to understand that the elementary science localization teaching strategy can improve the environmental perceptions of the students for such elementary science localization class would efficiently encourage environmental interest of the students.

• 한국태양에너지학회 논문집
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• 제39권5호
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• pp.53-63
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• 2019

This paper in order to efficiently operate zero energy buildings developed a methodology for optimal operation of PV + ESS active systems. This program consists of three steps. First step is PV optimal operation and second step is PV + ESS optimal operation. Third step is the analysis of the results by PV + ESS optimal operation. The optimal operation of PV + ESS was calculated by using Dynamic Programming (DP). Therefore, the optimal capacity and operating plan of PV + ESS in this study are calculated for electric load at building. This paper conducted case study to verify the validity of the developed algorithm. Also, the sensitivity analysis analyzed the effect of each variable on the optimal operation.

• Parasites, Hosts and Diseases
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• 제24권2호
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• pp.171-176
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• 1986

In order to obtain the most specific and sensitive antigen from crude antigens of Fasciola hepatica for the immunodiagnosis of bovine fascioliasis by the enzyme linked immunosorbent assay (ELISA), phosphate buffered saline extract of F. hepatica was prepared. The crude extract was fractionated into 7 antigens using sephadex G-100 column chromatography. Seven fractionated antigens were applied to ELISA, precipitation test and intradermal test, respectively. Results obtained are as follows: 1. The specificity (95% confidence interval in negative sera of bovine fascioliasis; Mean+$2{\times}SD$ of absorbence) of the first (MW>150,000) and the second antigens(MW 120,000) were 93.7%, but those of others including crude antigen showed 100%. 2. The sensitivity(positive sera of bovine fascioliasis having higher values with compared to the criterion) of the first, the sixth (MW 16,000) and the seventh antigen (MW<5,000) were 91.6%, 87.5% and 0%, respectively, but those of others showed all 100%. 3. The absorbance by ELISA using the fifth antigen (MW 26,000) was 8. 43-folds higher in the positive sera than that in the negative sera. This could be used as one of the most specific antigens for the immunodiagnosis of bovine fascioliasis. 4. In Ouchterlony test, precipitin lines were not found in the sera naturally infected with F. hepatica, but some were found in the sera of rabbits immunized with the crude antigens. The numbers of precipitin lines in the sera of rabbits were different in the different fractionated antigens. They were 6 in the crude, 2 in the second and the third antigens, 1 in the fourth, the fifth and the sixth antigens and absent in the seventh antigen, respectively. 5. The wheal size for bovine infected with F. hepatica was $2.46{\pm}0.15cm$ in the intradermal test antigen(saline extract of F. hepatica) supplied by the Veterinary Research Institute, Rural Development Administration, Korea. The wheal size of the first, the second and the third antigens were larger than that. of intradermal test antigen, whereas those of the fouth, the fifth, the sixth and the seventh antigens showed smaller than that of the intradermal test antigen. The results suggest that the fifth antigen may be specific antigen for the immunodiagnosis of bovine fascioliasis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제21권3호
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• pp.161-167
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• 2010

Objectives: In assessing behavioral/emotional problems in school-aged children, the importance of multi-informant reporting has been well documented. However, in clinical settings obtaining multiple informants' opinions has proven difficult. For that reason, we researched the agreement and predictive validity of the Child Problem-Behavior Screening Questionnaire (CPSQ) in order to reveal how accurate parents' assessments reflected teachers'opinions. Methods: We conducted the first screening for second- and third-grade children from 3 elementary schools in Seoul from 2003 to 2007 using the CPSQ. There were 1178 children included in the analysis. We then administered the Korean version of the Child Behavior Checklist (K-CBCL) as a second screening tool and subsequently, the ADHD Diagnostic System (ADS) and the Korean Educational Development Institute version of the Wechsler Intelligence Scale for Children (KEDI-WISC) was administered by a psychiatrist. We examined each item on the CPSQ and the subscale's agreement between parent and teacher as well as the predictive validity of the CPSQ in children diagnosed with emotional/behavioral problems. Results: The agreement rates between parents and teachers appeared high for questions 18 (0.433), 1 (0.385), and 2 (0.325). Among the subscales, a relatively high correlation was found for externalizing problems, attention deficit hyperactivity disorder, and cognitive problems. For all diagnosed children, their parents revealed a higher sensitivity and lower specificity than teachers. Conclusion: From these results, we confirmed that the CPSQ can be useful for sorting out externalizing and cognitive problems. There is a need for further study, however, with a larger sample size.

• 패션비즈니스
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• 제13권5호
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• pp.37-44
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• 2009

As the modern society has become highly industrialized and functionalized, the entry of women in public affairs has become brisk and extensive, and the studies of jackets which can satisfy the functions and designs for various activities have become important. Especially in the tailored collar which is the typical collar for female jackets, the studies such as scientific original form design, and design evaluation through analyzing functionality and sensitivity and others must be systematically carried out. In this study, therefore, the objective was placed in examining the actual state of the production of the tailored collar in the field of production first, and inquiring the general theories on the constituent elements of tailored-collar and production methods by analyzing it and comparing it with the educational tailored-collar production methods. First, in regard to the relation between the collar and the length of the backside neck of the bodice, in most cases, they were employing the method to enlarge the length of the backside neck of the bodice by shortening the length of the neck-base girth. That is, they were processing in order that the self collar band inside of the roll line and the fall of the collar can make a soft curved line. Second, when producing tailored-collar patterns, it is desirable to very the inclination according to the breath of the collar or thickness of the fabric because the stability of the inclination of the collar differs depending on the condition the collar is set, the girth of the collar edge. the broader the breath of the collar becomes, the thicker the fabric becomes, and the more the cloth is against the cold, it is necessary to make the inclination larger. Third, in the size relation between the upper collar and under collar, when sewing collars, it becomes thick and stabilized as it goes from the part in which extra pieces were put to the part in which extra pieces are not put. So you must make the upper collar larger by putting in extra pieces. The amount to be put in differs depending on characteristics of the materials.

• Structural Engineering and Mechanics
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• 제22권6호
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• pp.665-683
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• 2006

The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatly influenced by the properties of constitutive materials, the laminate structures, and load conditions etc, accompanied by many uncertainty factors. So the reliability study on FRP is an important subject of research. Many achievements have been made in reliability studies based on the probability theory, but little has been done on the roles played by fuzzy variables. In this paper, a fuzzy reliability model for FRP laminates is established first, in which the loads are considered as random variables and the strengths as fuzzy variables. Then a numerical model is developed to assess the fuzzy reliability. The Monte Carlo simulation method is utilized to compute the reliability of laminas under the maximum stress criterion. In the second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of the fact that there may exist a series of states between the failure state and the function state, a fuzzy assumption for the structure state together with the probabilistic assumption for strength parameters is adopted to construct the GFRM of composite materials. By defining a generalized limit state function, the problem is converted to the conventional reliability formula that enables the first-order reliability method (FORM) applicable in calculating the reliability index. Several examples are worked out to show the validity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivity analysis shows that some of the mean values of the strength parameters have great influence on the laminated composites' reliability. The differences resulting from the application of different failure criteria and different fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, and can provide an effective and synthetic method to evaluate the reliability of a system with different types of uncertainty factors.

• 대한전자공학회논문지SP
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• 제38권6호
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• pp.721-734
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• 2001

제안된 연구는 유방촬영영상(Mammogram)에서 종양의 추출에 관한 연구로서, 맘모그램의 특성을 파악하여 종양에 대한 자동적인 추출을 시행하였다. 처리과정에서 동질성 특성을 이용하여 정상조직인 Cooper's ligament로부터 종양조직을 분리하였고 고밀도 후보에 대한 처리방법으로 다중 문턱값 적용방식을 사용하였다. 추출된 부분을 8-연결성 관계를 사용하여 1차 후보를 추출하였다. 1차 추출된 각 후보에 대하여 명암값을 지형적 높이정보로 해석한 이분화영상으로 표현하여 이중원형성과 분포 비율을 비교하는 방법을 통하여 2차 후보 추출을 시행하였다. 최종적인 종양의 결정은 공간원형성 판단을 위한 반구 형태의 템플리트를 생성하여 비교하는 방법을 이용하여 후보에 대한 순위를 결정하였다. 알고리즘을 실제 종양이 확진된 환자의 136 예에 적용하여 추출된 결과와 전문의가 지적한 결과를 비교하여 93.38%의 민감도를 얻었으며, 최종추출 단계에서는 124 예에서 1 순위로 종양을 추출하여 97.63%의 FP(False positive)의 결과를 나타냈다.