• Journal of Navigation and Port Research
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• v.47 no.4
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• pp.231-238
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• 2023

The position of a light buoy is always flexible due to the influence of external forces such as tides and wind. The position can be checked through AIS (Automatic Identification System) or RTU (Remote Terminal Unit) for AtoN. As a result of analyzing the position data for the last five years (2017-2021) of a light buoy, the average position error was 15.4%. It is necessary to detect position error data and obtain refined position data to prevent navigation safety accidents and management. This study aimed to detect position error data and obtain refined position data by DBSCAN Clustering position data obtained through AIS or RTU for AtoN. For this purpose, 21 position data of Gunsan Port No. 1 light buoy where RTU was installed among western waters with the most position errors were DBSCAN clustered using Python library. The minPts required for DBSCAN Clustering applied the value commonly used for two-dimensional data. Epsilon was calculated and its value was applied using the k-NN (nearest neighbor) algorithm. As a result of DBSCAN Clustering, position error data that did not satisfy minPts and epsilon were detected and refined position data were acquired. This study can be used as asic data for obtaining reliable position data of a light buoy installed with AIS or RTU for AtoN. It is expected to be of great help in preventing navigation safety accidents.

• Journal of Industrial Convergence
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• v.21 no.5
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• pp.77-85
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• 2023

Suicide is the leading cause of death among Korean adolescents. There is a growing interest in the role of loneliness as a risk factor for suicide ideation and depressive symptoms. However, little is known in the Korean context. This study analyzed a total of 109,796 respondents from the Korea Youth Health Behavior Survey in 2020 and 2021. Multiple logistic regression models were implemented to test the association between loneliness and either of suicidal ideation and depressive mood. Covariates included demographic characteristics, school enrolled, household income, living arrangement, self-rated health, and the number of times treated for violence. Adjusted odd ratio (OR) and 95% confidence intervals (CI) were computed. 12.0% of adolescents reported to have felt lonely frequently and 3.0% always. 11.8% and 26.0% had suicidal ideation and depressive mood, respectively. The prevalence of suicidal ideation was higher in the always-lonely adolescents (52.6%) than in the frequently-lonely adolescents (35.1%). The always-lonely adolescents were nearly 30 times more likely to have suicidal ideation (OR=30.7; 95% CI, 27.1 - 34.8) and to feel depressed (OR=32.5; 95% CI, 29.2 - 36.4) than adolescents who felt never lonely. In conclusion, Loneliness was a major risk factor for suicidal ideation and depressive mood among Korean adolescents. Monitoring and addressing the condition of loneliness may help reduce suicidal ideation and depressive mood.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.4
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• pp.169-179
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• 2016

This study was to investigate special education teachers' teaching in reading and writing to university students with intellectual disabilities. For this study, we surveyed 71special education teachers who work in Gwangju, Daegu and Busan. As a result, in order to identify students' reading and writing abilities, they were more likely to use their own tests which they made for themselves than standardized tests. When teaching students, they used their own teaching experiences and advices from colleagues and senior teachers regarding problem-solving methods and reliable information while the knowledge they learned at school showed low frequency in use. Despite using mainly whole-word approach when instructing reading and writing, it appeared that teachers' teaching experiences and diversity of textbooks also have an influence. Regarding needs of education participation for teaching students, there were high needs and interests in teaching methods of writing, textbooks and teaching materials by the characteristics of disability, reading and writing development, reading and writing disabilities. In case of difficulties and needs in teaching students, there was a high demand of development of a wide variety of teaching materials and tools and, preparation for sufficient textbooks and test tools, while difficulties in teaching appeared in lack of knowledge about reading and writing, lack of screening/evaluating tools, and evaluating and teaching oriented to each disability characteristic.

• 한국체육학회지인문사회과학편
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• v.55 no.3
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• pp.43-57
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• 2016

This narrative study aims to describe the experience of P.E. assessment that was conducted by P.E. teachers of Korea Science Academy of KAIST, and interpret the educational significance that was found in the process. The study participants were two P.E. teachers who were selected by decisive case sampling method. Data were collected mainly through official interviews with study participants, and through researcher's field notes, informal interviews, various minutes, students' evaluation of teaching, and emails between the researcher and study participants. Data were analyzed through inductive categorization, and to gain veracity of the study, there were integration of diverse materials, advice and suggestions of fellow researchers, continuous confirmation of study texts by study participants. Study participants, while conducting P.E. assessment in Korea Science Academy of KAIST, experienced effectiveness of evaluation such as qualitative development of P,E. classes in accordance with the simplified assessment, freedom from the chores of handling assessment results, students' improved perceptions of P.E. class, realization of safe classes without excessive competition, and the possibility of giving alternative evaluations to pass/fail system but at the same time experienced limitations such as concerns over gaining validity and reliability of P.E. evaluation, the students' attitude who take lightly of P.E. class, and the reality that teachers cannot fail students. The evaluation experiences of the two P.E teachers were educationally interpreted as encounter with good P.E. classes, invitation to P.E. class criticism, and the start of school P.E. culture that is led by students.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.475-485
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• 2008

This paper intends to enhance the reliability and performance of domestic elastomeric bearings through the proposal of directions for the improvement of their stiffness regard to the Korean industrial standard KS F 4420 relative to the evaluation of design/fabrication/quality. Therefore, comparative analysis of the compressive elastic modulus, stiffness measurement method and performance evaluation method of KS F 4420 with those of Eurocode, Japanese bearing manual, and ISO code was performed, and measurement tests on the compressive stiffness and shear stiffness of common elastomeric bearings produced in Korea were conducted. The experimental results reveal that differences of about 20% and 13% occurred respectively for the compressive stiffness and shear stiffness according to the definition adopted for the stiffness. The measured values for the stiffness of the domestic elastomeric bearings were also verified to exhibit large deviation from the formula proposed by KS F 4420. Elastomeric bearings that does not have appropriate compressive stiffness required at the design can result in uneven deflection at supports of bridges and excessive stress in girders. Accordingly, the establishment of compressive elastic modulus formula and performance evaluation criteria fitted to the domestic circumstances through the execution of performance evaluation of bearings presenting diversified shapes and shape factors appears to be necessary for the domestic bearings to meet the performance required in design.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.687-693
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• 2006

Image co-registration is the process of overlaying two images of the same scene, one of which represents a reference image, while the other is geometrically transformed to the one. In order to improve efficiency and effectiveness of the co-registration approach, the author proposed a pre-qualified area matching algorithm which is composed of feature extraction with canny operator and area matching algorithm with cross correlation coefficient. For refining matching points, outlier detection using studentized residual was used and iteratively removes outliers at the level of three standard deviation. Throughout the pre-qualification and the refining processes, the computation time was significantly improved and the registration accuracy is enhanced. A prototype of the proposed algorithm was implemented and the performance test of 3 Landsat images of Korea. showed: (1) average RMSE error of the approach was 0.435 pixel; (2) the average number of matching points was over 25,573; (3) the average processing time was 4.2 min per image with a regular workstation equipped with a 3 GHz Intel Pentium 4 CPU and 1 Gbytes Ram. The proposed approach achieved robustness, full automation, and time efficiency.

• Journal of Ethics
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• no.77
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• pp.191-215
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• 2010

In dieser vorliegenden Arbeit wird die eigentliche Bedeutung des Hauses in bezug auf M. Heidegger, G. Bachelard und O. F. Bollnow analysiert. Bei Heidegger ist das Wohnen ein Wesensmerkmal des Menschen und das Haus ein Raum des Wohnens als das Pflegen und Schonen. Insbesondre Bachelard hat die schuetzend Funktion des Hauses und das Haus als das Glueck des Wohnens behauptet. Fuer Bollnow bedeutet das Haus eine Mitte des menschlichen Lebens und der Welt. Heidegger behauptet, dass wir so in der eigentlichen Not des Wohnens, d.h. in der Heimatlosigkieit sind. Wir muessen nach die Bedeutung des Hauses nicht als einen wirtschaftlichen Wert sondern als den eigentlichen Wohnraum denken und das Wohnen lernen. Bachelard weist darauf hin, dass das Haus als ein gluekliche Raum ein wesentliches Trauen voraussetzt. Und er versteht das Haus mit dem dialektischen Zusammenhang zwischen dem Haus und der Welt. Bollnow versucht ueber dem Raum in anthropologische Hinsicht zu betrachten. Er behauptet, dass der Mensch seine wesentlichen Bedeutung durch das Wohnen hat. Durch die Vermenschlichung des Raumes muss der Mensch die Verantwortlichkeit ueber den Raum uebernehmen. In der heutigen Gesellschaft bemessen das Haus sich nur mit einem wirtschaftlichen Wert. Wir muessen das Haus lesen, und die eigentliche Bedeutung des Hauses.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.125-125
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• 2022

저수지 운영자료는 다목적 댐 경우와 마찬가지로, 유입량, 저수량, 방류량 자료로 구성된다. 여기에 강우량을 포함하여, 실시간으로 관리돼야 한다. 그러나 우리나라 저수지는 저수율 자료만 관리하고 있다. 유입량, 방류량이 없는 것이 아니고 관리를 하지 않는다. 강우량은 전혀 없다. 큰 문제인데, 아직도 그 심각성을 모르고, 대충하면 되는 줄 알고 있다. 가장 기초가 되는 일을 무시하고 물관리를 하고 있는 상황이고, 누구도 그 신뢰성을 믿지 않고 있다. 여기서는 이를 해결하는 방안으로 준 실시간 물수지 모형을 구축하여, 10분 단위, 30분 단위, 1시간 단위로 저수위, 저수량, 유입량, 방류량, 강우량을 연속하여 생산하고 검증하는 체제를 제시한다. 준 실시간의 뜻은 계산에 의하지 않고 유입량을 모의에 의해 적용하고 검증하는 과정이 필요하여, 실시간 보다 하루 이틀 늦게 자료를 생산한다는 의미다. 대상 저수지는 유역 내 강우량 수집이 가능한 유역면적 218.80km², 유효저수량 3,494만m³, 수혜면적 5,117 ha인 탑정지를 선정했다. 탑정지 방류량은 탑정1(폭 7.5m×높이 1.5m), 탑정2(4m×1.6m), 양수장(3m×1.6m) 수로로 관개용수 공급량과, 9연의 수문(9m×7.5m)으로 홍수기 방류량으로 구성된다. 분석기간은 1월1일부터 1시간 단위로 연속하여 기간은 자유롭게 설정하여 검정하는 체제를 갖추고 검증된 결과를 제시토록 했다. 2021년 9월의 1시간 단위의 탑정지 저수지 물수지 모의 결과를 요약하면 다음과 같다. 첫째, 탑정지 유역의 환경부 관리 장선, 양촌, 연산 관측소의 면적우량은 최대 15.3mm, 총 160.4mm(3,510만m³)였고, ONE 모형에 의해 연속유량을 모의한 결과, 유입량은 최대 35.6m³/s, 총 1,464만m³로 유출률 41.7%였다. 둘째, 탑정1, 탑정2, 양수장 수로의 수위자료에 수위-유량 관계식을 적용해 수로유량을 산정한 결과 합하여 최대 16.8m³/s였고, 총 548만m³였으며, 수문 방류량은 최대 20.0m³/s였고, 총 108만m³였다. 셋째, 저수지 수위는 관측수위는 EL.28.21~29.38m, 평균 EL.28.87m, 모의수위는 EL.28.08~29.62m, 평균 EL.28.80m로 나타났고, R²는 0.910로 만족한 결과를 얻었다. 정리하면 저수지 운영자료가 없는데도, 10분, 1시간 단위로 연속으로 유입량, 저수량을 모의하여 관측저수량과 비교한 결과가 괄목할 신뢰도를 나타냈다. 이를 바탕으로 저수량, 유입량, 방류량, 강우량 등 준 실시간 저수지 운영자료 생산체제를 마련한 것으로 결론을 내렸다.

• 한국노년학
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• v.34 no.2
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• pp.215-228
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• 2014

This study aims to develop a scale to measure the elderly's intention on home renovation and to verify its validity. As a methodological study based on the theory of planned behavior, this study provides 26 preliminary items in the pre-test. The first main test, performed to verify the content validity of the developed items, was followed by a second test of construct validity and reliability. As the result of the content validity test targeting experts, some of the original 26 items were excluded, while others were combined for a total of 22. As the result of the construct validity test of the scale, targeting the elderly aged 65 and over, the 22 items were narrowed down to 14 items, excluding the items that were unsuitable for communality and Eigen value. After once more conducting a factor analysis, the items were classified into five factors with a total cumulative variance of 72.5% and a Cronbach's α of 0.75. This study will contribute to the discussion of housing for the elderly by giving force to environmental regeneration activities through facilitating the identification of the home owners' intentions to renovate in order to improve the physical environment in decayed areas at a public level.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.6
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• pp.355-364
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• 2023

The arbitrary Lagrangian-Eulerian (ALE) method has been extensively researched owing to its capability to accurately predict the propagation of blast shock waves. Although the use of the ALE method for dynamic analysis can produce unreliable results depending on the mesh size of the finite element, few studies have explored the relationship between the mesh size for the air domain and the accuracy of numerical analysis. In this study, we propose a procedure to calculate the optimal mesh size based on the mean squared error between the maximum blast pressure values obtained from numerical simulations and experiments. Furthermore, we analyze the relationship between the weight of explosive material (TNT) and the optimal mesh size of the air domain. The findings from this study can contribute to estimating the optimal mesh size in blast simulations with various explosion weights and promote the development of advanced blast numerical analysis models.