• Title, Summary, Keyword: 사전-사후 비교 평가

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The Risk Assessment and Prediction for the Mixed Deterioration in Cable Bridges Using a Stochastic Bayesian Modeling (확률론적 베이지언 모델링에 의한 케이블 교량의 복합열화 리스크 평가 및 예측시스템)

  • Cho, Tae Jun;Lee, Jeong Bae;Kim, Seong Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.5
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    • pp.29-39
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    • 2012
  • The main objective is to predict the future degradation and maintenance budget for a suspension bridge system. Bayesian inference is applied to find the posterior probability density function of the source parameters (damage indices and serviceability), given ten years of maintenance data. The posterior distribution of the parameters is sampled using a Markov chain Monte Carlo method. The simulated risk prediction for decreased serviceability conditions are posterior distributions based on prior distribution and likelihood of data updated from annual maintenance tasks. Compared with conventional linear prediction model, the proposed quadratic model provides highly improved convergence and closeness to measured data in terms of serviceability, risky factors, and maintenance budget for bridge components, which allows forecasting a future performance and financial management of complex infrastructures based on the proposed quadratic stochastic regression model.

Study on Improving the Environmental Performance of a Railway Vehicle through a Life Cycle Assessment of the Tilting Train (틸팅열차의 전과정평가를 통한 철도차량 환경성 개선방안연구)

  • Lee, Cheul Kyu;Kim, Yong-Ki;Lee, Jae-Young;Choi, Yo-Han;Kim, Cho-Young
    • Journal of the Korean Society for Railway
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    • v.17 no.1
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    • pp.1-6
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    • 2014
  • Recent international environmental regulations are focused on reducing pre-contamination and on sustainable development prior to the usage stage of a product. The Environmental Performance Declaration is being used as a tool for quantifying the environmental performance of products, to reduce contamination in advance, and for advertising the results of railway vehicles in Europe. In this study, a life cycle assessment of the tilting train was conducted, the first such case study in Korea, according to the ISO 14025 standard and Korea EDP (Environmental Declaration of the Product) rule. As a result of the LCA, the life cycle carbon emission of the tilting train was determined to be $3.54{\times}10^7kgCO_2eq.$ which is higher than that of a European train. Also, the amount of $CO_2$ emission of the Mcp and car body is higher than that of the other car and bogie.

구조물 축소 모형시험과 수치해석에 의한 구조물 안전도 평가

  • 이명규
    • Computational Structural Engineering
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    • v.11 no.1
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    • pp.80-89
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    • 1998
  • 본 기사에서는 기존 구조물의 구조를 변경하여 사용하는 경우 구조물 축소모형시험과 수치해석을 이용하여 안전도를 합리적으로 평가하는 절차에 관하여 지하철 정차장 구조물을 예로하여 살펴보았다. 구조물의 안전도를 평가하기 위한 구조물 축소모형 시험에서는 원형구조물의 실제 거동을 나타내는 모형의 제작이 가장 중요한 사항이다. 이를 위해서 적절한 상사율을 가지는 구조재료의 선정, 합리적인 경계조건의 설정, 실제하중을 고려한 재하방법 등을 결정하여야 한다. 구조재료의 선정과 모형의 축소율은 모형구조의 거동이 탄성범위 내인가 또는 극한거동인가에 따라 결정되는 것이 일반적이다. 안전도 평가를 위한 모형구조물의 제작과정에서는 원형구조물 거동을 수치해석을 통하여 예측하는 과정이 필요하며 이러한 사전해석(pre-analysis)을 통하여 구조물의 개략적인 거동과 측정항목을 정하며, 또한 합리적인 재하방법을 결정하게 된다. 모형구조물에 대한 재하시험을 통하여 원형구조물의 거동을 상사비를 적용하여 바로 예측할 수 있으나 재하하시험후 측정된 사항에 대하여는 모형구조물에 대한 사후해석(post-analysis)를 수행하여 측정값과 비교 검토하여 거동의 일치성을 입증하는 것이 일반적이다. 이런 과정을 거쳐 검증된 수치해석모델을 이용하여 실험에서 고려하지 않은 여러가지 하중조건에 수치적으로 검토할 수 있으며, 이를 이용하여 안전도검토와 적절한 대책을 수립할 수 있게 된다. 사전해석-모형시험-사후해석의 절차에 따른 구조물의 모형실험의 사례는 미국과 유럽에서 찾아볼 수 있으며 이를 통하여 수치해석기법의 발전이 이루어지고 있다. 현재까지 우리나라에서는 구조물 모형실험에 관련된 연구가 활발하지 못한 편이며, 상대적으로 경험이 적게 축적되어 있는 실정이다. 그러나 수치해석기법의 발전과 실제구조물의 안전도를 합리적으로 파악하기 위해서는 구조물모형 실험이 필수적이며 앞으로 연구가 활발히 이루어져야 할 분야로 사료된다.leic acid와 palmitic acid가 주요 지방산이었으나 싸리버섯은 중성지질에서 oleic acid의 함량이 높았다.n the part of special landscape management area, it is necessary to introduce landscape impact assessment system to more effective landscape management.ch served as supporting organizations. The control of the construction and management of the royal garden and landscape was held by decision makers, executors of works and management. 2) The general process of the construction and management of the royal garden and landscape included Sangji and Kyuho다 as the first step; In case of buildings and facilities, according to former examples and drawings, the most of the planning and design was already fixed. In the case of landscape, those things aimed at construction according to the existing lie of the land. The works in the 2nd step; This process was divided into the construction of facilities and planting. In case of construction of facilities, those works were done by Togam and

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Traffic Accident Reduction Effects of the All-Red Clearance Interval (ARCI) Operation (전적색신호시간 운영에 따른 교통사고 감소효과)

  • Park, Byung-Ho;Jung, Yong-Il;Kim, Kyung-Hwan
    • Journal of Korean Society of Transportation
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    • v.30 no.2
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    • pp.21-27
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    • 2012
  • This study deals with the relationships between signal operation and traffic accident of signalized intersections. The objective of this study is to analyze the traffic accident reduction effects on the operation of all-red clearance interval (ARCI). This study gives particular attentions to evaluating the traffic accident reduction effects of ARCI at 37 signalized intersections in Cheongju using before-after evaluation with comparison group. The main results are as follows. First, the number of traffic accidents, fatalities and injuries has changed before operating ARCI and thereafter. Second, the result of before-and-after evaluation with comparison group showed that the number of accidents was reduced by 20.0% and that the number of fatalities and injuries was reduced by 28.0%. Finally, reduction effects from operating ARCI were evaluated to be 6.0~35.0% in the number of accidents and 18.0~37.0% in the number of fatalities and injuries.

Exploring the Use of Melody During RAS Gait Training for Adolescents with Traumatic Brain Injury: A Case Study (외상성 뇌손상 청소년 대상 리듬청각자극(RAS) 보행 훈련 시 선율 적용 사례)

  • Park, Hye Ji
    • Journal of Music and Human Behavior
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    • v.12 no.2
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    • pp.19-36
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    • 2015
  • The purpose of this study was to examine the effects of rhythmic auditory stimulation (RAS) on gait parameters, with and without the presence of a melody, for adolescents with traumatic brain injury (TBI). Three adolescents with TBI received a total of ten individual RAS training sessions. At pre and posttest, spatiotemporal parameters including cadence, velocity and kinematic parameters were measured using the VICON 370 Motion Analysis System. The results showed no significant difference in gait velocity between the two conditions, thus the presence of the melody condition did not impact the outcome of RAS gait training. On the other hand, all participants showed improvement in gait function after RAS training. The cadence, velocity, stride length, and symmetry were increased and the stride time was reduced after training. The motion analysis demonstrated that the movement patterns of hip and knee joints improved, as they were more similar to normal gait, which indicates that the walkings tance became more stable. The research findings indicate that rhythm is the primary factor in mediating gait functions via RAS training. This study also supports that RAS training can effectively improve the gait function for adolescents with TBI.

A study on the development of family resilience enhancement program for couples in early stage of marriage (결혼초기부부의 가족레질리언스 강화 프로그램 개발 연구)

  • Choi, Jung Sook
    • Korean Journal of Family Social Work
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    • no.23
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    • pp.103-152
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    • 2008
  • The purpose of this study was to develop a program for couples in early stage of marriage for enhancing family resilience based on the concept of 'Family Resilience' by Walsh. Based on the literature review of couples in early stage of marriage, marital enrichment, and Family Resilience, a program focused on belief system, organizational pattern, and communication process was designed and implemented. The program was applied to seven couples in early stage of marriage for four (3hours/session/week) sessions. The Wilcoxon Signed Ranks Test was used to compare the pre and post effects of the program. By operating a focus group composed of the program participants, a qualitative analysis of the participant's evaluation was performed. The pre and post comparative analysis showed a significant enhancement in belief system, organizational pattern, communication process, and dyadic adjustment. The results of the qualitative study in the focus group also reinforced the effectiveness of the program. The evaluation showed that the 3 hour/ 4 session program was appropriate in terms program format. The significances of this study are the concretion of the concept of Family Resilience and providing practice tools for the daily practitioner.

Development and application of a Teaching and Learning Plan and Practical Performance Assessment Tools to Promote Communication Between Teenagers Children and Their Parents: focusing on conversation analysis of real conversation in UCC video projects (청소년 자녀와 부모간 의사소통 개선을 위한 교수학습 과정안과 실제 상황적 수행평가 개발 및 적용 - 부모자녀의 실제대화 UCC동영상을 활용한 대화분석을 토대로 -)

  • You, Hye-Jung;Cho, Byung-Eun
    • Journal of Korean Home Economics Education Association
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    • v.23 no.3
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    • pp.139-160
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    • 2011
  • The purpose of this study is twofold: (i) to develop a teaching and learning plan and practical performance assessment tools for the improvement of teenager-parent communication and relationships as well as explore their effects on the communication in the everyday family life; and (ii) to find the underlying problems of teenager- parent communication through conversation analysis and to provide a improved dialogue model. We provided the experimental group with a performance task of communication training between teenagers and their parents in the real family situation while the control group practiced communication skills in a learning situation. However for both classes, before and after performance tasks were equally provided. The experimental group exhibited a longer conversation time with their parents, better communication skills, and higher degrees of relational satisfaction than the control group. Conversation analysis revealed that the experimental group reduced the use of blocking techniques in the teenager-parent conversations more than the control group, and all so raised the frequency of functional communications more than the control group. In both areas of communication in the experimental group was significantly improved, Most notably, a problem-solving case through no-lose conflict resolution methods was effective, succeeding by 70% in the e experimental group and 43.3% in the control group. Parents use blocking techniques like admonition, lecturing, blaming. sarcastic remarking, ordering and so forth, while teenagers use dispute, avoidance, blaming, and teasing in this order. The communication problems during the conversation process, teenagers' evasive and rebellious way of speaking instigates adverse communication responses from parents, so their conversation tends to unfold as ambiguous evasion opposed to: inquiring or evasion by short answers vs. ordering-preaching, or disputing vs. criticizing-making sarcastic, disputing vs. disputing-teaching, and criticizing vs. criticizing.

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Safety Evaluation of Flashing Yellow Operation at Night (야간 황색점멸신호 운영에 따른 안전성 평가)

  • Beak, Tae Hun;Park, Byung Ho
    • Journal of Korean Society of Transportation
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    • v.31 no.5
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    • pp.16-25
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    • 2013
  • This study deals with the relationships between flashing operation and traffic accident at signalized intersections. The objective of this study is to analyze safety effects of the yellow flashing operation at night. In pursuing the above, this study gives particular attention to evaluating the safety results from signal operation of Cheongju's 190 signalized intersections using before-after evaluation with comparison group that are categorized by highway function. The main results are as follow. First, the numbers of traffic accidents and of fatalities/injuries in two highway types (arterial and collector road) have increased after operating the yellow flashing signal at night. Second, the numbers of accidents, fatalities/injuries, severe accidents and of fatalities/severe injuries in group A(arterial) have increased by 19%, 36%, 15% and 14%, respectively. Finally, the numbers of accidents, fatalities/injuries, severe accidents and fatalities/severe injuries in group B (collector) have increased by 50%, 64%, 41% and 77%, respectively.

Exploring the Impact on Problem Solving Ability according to the Level of Structuring of Curriculum Tasks in PBL Activities (PBL 활동에서 교육과정 편성 과제의 구조화 정도가 문제해결력에 미치는 영향 탐색)

  • Lee, Eun-Chul
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.282-291
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    • 2020
  • This study was conducted to explore the effects of students' problem solving ability according to the level of structuring of curriculum tasks in PBL activities. The study was conducted on 60 college students in curriculum classes. Problem solving ability was measured at the beginning of the semester. And after the midterm exam, PBL activities were conducted. 30 experimental groups performed unstructured tasks. 30 comparison groups performed semi-structured problems. After the task was completed, problem solving ability was measured at the end of the semester. Collected data were analyzed using ANCOVA. As a result, it was verified that the experimental group had a statistically significant improvement in information collection, evaluation, and feedback level than the comparative group.

A study on applying Problem-Based Learning to a course entitled 'Teaching practice' for prospective Home Economics teachers (예비가정과교사를 위한 <교직실무> 수업에 문제중심학습을 적용한 연구)

  • Yu, Nan Sook
    • Journal of Korean Home Economics Education Association
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    • v.27 no.4
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    • pp.1-18
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    • 2015
  • The purpose of this study was to conduct a course entitled 'Teaching practice' applying Problem Based Learning(hereafter PBL) for perspective Home Economics teachers to explore the applicability of PBL to the course. A course entitled 'Teaching practice' was carried out for 17 undergraduate students from the 2nd of March till 11th of June in 2014. Pre- and post-tests to measure teacher disposition were performed to investigate the effectiveness of the course applying PBL. Three questions for PBL were developed, were determined after obtaining verification of the questions from 5 experts, and were used for the course entitled 'Teaching practice'; Developing teaching-learning plan, establishing plan for homeroom class management, and designing assessment of Technology & Home Economics. The processes of PBL include defining the problem, planning problem solutions, reassessing the problem, identifying possible solutions, and performance presentation. Procedures for solving one problem of PBL took 4 weeks and teacher disposition assessment for effectiveness of PBL was carried out for pre- and post tests. The reflection journal showed that even though it was their first experience of PBL, instructor's feedback, group activities, and individual activities were helpful for solving the problems of PBL. The result of dependent t-test for paired samples revealed significant differences between the pre- and post tests, which means that there was effectiveness of the course applying to PBL on teacher disposition of prospective Home Economics teachers.