• Journal of the Korean Geosynthetics Society
• /
• v.10 no.2
• /
• pp.35-43
• /
• 2011

Permeable Reactive Barriers (PRB) method is an economical method that does not require any other methods to be operated once it is installed as it controls of groundwater flow in the barrier, which is inserted a reactive material on the way of pollutant. The major dominant element of PRB is a reactive material in the reactive wall, and such factors as purification efficiency and used time based on the chemical and physical features in between the reactant and pollutant. High purification efficiency can be expected when a rational design that is synthetically considered in features of packing density, operation period, and adsorption reactant of pollutant. A column test was conducted for an application test using CFW as its adsorption reactant in order to remove copper($Cu^{2+}$) in the PRB system. The CFW was used for the reactant and selected inflow speed, density and thickness of PRB as its necessary factors for design of PRB. As a result of the experiment, the removal efficiency decreased as operating time of PRB increased and the efficiency linearly increased upon the length. Therefore, it is confirmed that the thickness of reactive materials in PRB system can be designed using the proposed formula considering purification time and density of CFW.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.5
• /
• pp.2041-2048
• /
• 2013

It is necessary to evaluate methods for reasonable diagnosis for public transportation. However, previous studies have the problems in evaluation ground and propriety. Therefore, this research develop the method and equation for evaluating bus route considering interregional equity and route doubleness. This study developed in bus route evaluation method using Seoul bus Zone, and included the result of evaluation test using 199 route Seoul trunk bus (blue bus). Zone (0) (Jongno-gu, Jung-gu and Yongsan-gu) has the highest score in Evaluation result. Also this zone has good bus route, so it is easy to move to other Zone. It is possible to change and add the bus route to use the equation in this study, considering interregional equity.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.14-14
• /
• 2017

안정하도란 하도형성유량이 발생하는 조건에 대해 단면내에서 발생하는 유사량과 유입되는 유사량이 평형상태를 유지하는 단면을 의미하며, 안정하도 평가 및 설계란 현재 단면을 안정하도 단면과 비교하여 평가하거나 안정하도를 만족하는 하상경사와 하폭, 수심을 도출하는 과정을 의미한다. 이러한 안정하도 평가 및 설계는 하천을 정비하거나 복원하는 과정에서 장기적인 하상 평형상태를 고려하기 위해 적용할 수 있으며, 하상 침식 혹은 퇴적에 대해 지점별 평가방법으로 활용 할 수 있다. 안정하도 단면은 상류에서 유입되는 유사량과 대상구간의 발생 유사량의 평형조건에 의해 결정되기 때문에 유입되는 유사량 자료의 정확성과 대상구간 발생 유사량 산정의 정확도가 전체 평가 결과의 신뢰도에 가장 중요한 요소로 작용한다. 그러나 현재까지 활용되어 온 안정하도 단면 계산 방법의 경우 대상구간 발생 유사량 결정을 위한 유사이송공식의 선택이 특정 공식으로 한정되어있어 국내 하상과 적합한 유사이송공식의 적용이 매우 제한적이었다. 따라서 본 연구에서는 이러한 기존의 안정하도 평가 및 설계 방법을 개선하기 위해 다양한 유사이송공식의 적용이 가능한 안정하도 평가 모델의 알고리즘을 제시하였으며, 관련 분야의 실무자가 쉽게 활용 할 수 있도록 사용자 친화적인 사용자 친화적인 안정하도 평가 및 설계 프로그램(Stable Channel Analysis and Design, SCAD)을 개발하였다. 본 연구에서는 기존의 안정하도 단면 계산 방법인 Copeland 방법을 분석하여 새로운 알고리즘을 개발하였으며, 단면 유사량 분석 계산과정에서 자갈하상 공식을 포함한 총 다섯 가지의 유사이송공식을 새롭게 추가하였다. 개발된 SCAD 프로그램은 정확도 및 적용성 향상을 위해 청미천과 내성천 모래하상 구간 그리고 원주천 자갈하상 구간에 대해 시험계산을 수행하였고 평가 결과를 프로그램 개선을 위해 적극 활용하였다. 또한 웹 포팅 프로그램 구축을 통해 다양한 사용자가 특정 웹사이트에서 프로그램에 쉽게 접근할 수 있도록 하였다. 본 연구에서는 개선된 안정하도 평가 및 설계 프로그램을 활용하여 다양한 유사이송공식 선택에 따른 안정하도 산정 결과 값의 변화를 분석하고 그 범위를 정량적으로 제시하였다.

• Journal of Convergence Society for SMB
• /
• v.6 no.1
• /
• pp.25-32
• /
• 2016

With the change and development of modem architecture, architectural configurations are increasingly diversified and irregular. However, the building configurations without proper seismic considerations may cause severe damages under earthquake loads. Therefore, it is necessary to establish and implement more properly classified, specific and advanced conceptual seismic design strategies. This study explores the relationship between building configurations and seismic performance by adopting several horizontal building configurations with various re-entrant corners. For the clear comparison of five different horizontal configuration models, almost aspects of structural properties are equalized. The equivalent static analyses are conducted with the aim of understanding the characteristics of various re-entrant comers under standard earthquake loads. The seismic advantages of regular configuration model are clearly approved and the structural weak points at the re-entrant comers are investigated numerically and graphically.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.237-237
• /
• 2022

우리나라 하천 내에 설치된 횡단구조물은 보 35,000개소 이상으로 전국 하천의 0.6 km마다 수공구조물이 위치해 있으며 이로 인해 종적(longitudinal) 연결성에 영향을 미치는 것으로 나타났다. 농어촌연구원의 조사에 따르면 하천 횡단구조물이 설치된 구간에 어도 설치율은 14.9%로 나타났으며 이는 수생태 관점에서 연속성이 매우 열악한 상태임을 확인 할 수 있다. 이에 우리나라 각 부처 국토교통부, 환경부 등에서는 수생태 연속성을 확보하고자하는 노력이 지속되고 있으며 대표적으로 어류의 이동통로인 어도를 설치하거나 기존 어도의 효율을 향상시키기 위하여 개보수 작업을 지속적으로 실시하고 있다. 어도의 기능을 평가하기 위해서는 어도 내의 수리특성을 정확히 파악하는 것이 중요한데 연속적인 구조물로 구성된 어도 내 흐름은 매우 복잡하다. 특히 어도 내 구조물간 상호작용에 의하여 비정상 흐름이 발생하며 구조물 뒤에서는 사수역(dead zone)이 형성된다. 사수역에서 나타나는 와류의 거동은 구조물의 기하학적 특성에 따라 변화한다. 본 연구에서는 2차원 수심적분 수치모형을 활용하였으며 벽면 근처 점성저층의 유속분포을 재현하기 위하여와 점성항에 감쇠함수(damping function)를 고려하였다. 수치모형의 검증을 위해 실내 실험수로의 직선 개수로에서 PIV(particle image velocimetry)를 활용하여 연속적으로 배치된 구조물에 의한 유속자료를 활용하였다. 이 결과는 향후 새로운 어도설계 혹은 기 설치된 어도의 수리학적 기능을 평가하는데 활용이 가능할 것으로 보인다.

• Journal of Internet Computing and Services
• /
• v.8 no.5
• /
• pp.1-10
• /
• 2007

Recently, the web 2.0 services which appear by exponential extension of the Internet can be expressed with the changes in the quality of structural evolution and in the quantity of increasing users. The structural base is in user participational architecture, the web 2.0 services such as Blog, UCC, SNS(Social Networking Service), Mash-up, Long tail, etc. play a important role in organization of web, and grouping and searching of user participational data in web 2.0 is broadly used by folksonomy. Folksonomy is a new form that categorizes by tags, not classic taxonomy skill. it is made by user participation. Searching based on tag is now done by a simple text or a tag cloud method. But searching to consider and express the relations among each tags is imperfect yet. Thus, this paper provides the relational searching based on tags using the relational graph of tags. It should improve the trust of the searching and provide the convenience of the searching.

• Journal of Korean Home Economics Education Association
• /
• v.33 no.4
• /
• pp.119-137
• /
• 2021

This study aimed to develop a teaching-learning process plan for the 'adolescent nutrition and dietary behavior' unit of middle school technology and home economics through blended learning teaching method. "Analysis-Design-Development-Evaluation and Revision" model developed by Korea Institute of Curriculum and Evaluation(KICE) was applied to developing the teaching-learning process plan. The authors analyzed subject contents suitable for blended learning, and then designed a teaching-learning process plan by selecting the topics, developing the teaching strategies, and deciding on the media and evaluation tools for each class. Based on the plan for each week, the final version of the teaching-learning process plan, handouts for activities, and evaluation tools were developed. The teaching-learning process plan was revised and supplemented based on the expert verification results. The developed teaching-learning process plan which applied blended learning method was considered suitable for the current curriculum, and the group presentation activities implimented in the online classes were found to encourage learners' participation and interest. Also, the developed teaching-learning process plan could be used in the online only environment without any issues depending on the intention of the classes, by the appropriate use of distance learning tools such as Paddles or Thinkerbells. The developed teaching-learning course plan is expected to be effectively used in either online or blended learning environment, as a means of helping adolescent students improve their dietary life.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.7
• /
• pp.577-582
• /
• 2020

Electricity produced at power plants is distributed to consumers through several stages of substations. At this time, an ultra-high voltage transformer is needed in the initial transmission stage to transmit a voltage suitable for each consumer. A high voltage, non-uniform electric field is formed at the end of the winding of the ultra-high voltage transformer, which carries a risk of dielectric breakdown. The winding of the ultra-high voltage transformer is an electrode, which is the key to converting the magnitude of the voltage. A non-uniform electric field is formed along the shape of the winding end, resulting in high electrical stress. The static ring installed at the upper and lower ends of the winding is used to disperse the stress at the winding end. Several variables should be considered when designing a static ring. Among them, this study examined how the curvature of the static ring, the thickness of the insulating paper, the number of barriers, and barrier thickness affect the electrical stress of the static ring using the Finite Element Method. Suggestions to be considered when designing the static ring are proposed through the FEM results.

• Computational Structural Engineering
• /
• v.10 no.2
• /
• pp.255-263
• /
• 1997

The optimum design of most structural systems used in practice requires considering design variables as discrete quantities. The present paper shows that the linear approximation method is very effective as a tool for the discrete optimum designs of unsymmetric composite laminates. The formulated design problem is subjected to a multiple in-plane loading condition due to shear and axial forces, bending and twisting moments, which is controlled by maximum strain criterion for each of the plys of a composite laminate. As an initial approach, the process of continuous variable optimization by FDM is required only once in operating discrete optimization. The nonlinear discrete optimization problem that has the discrete and continuous variables is transformed into the mixed integer programming problem by SLDP. In numerical examples, the discrete optimum solutions for the unsymmetric composite laminates consisted of six plys according to rotated stacking sequence were found, and then compared the results with the nonlinear branch and bound method to verify the efficiency of present method.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.37 no.6
• /
• pp.66-72
• /
• 2010

Seoul City planned "Dreamland" to be in harmony with the huge woods and park. It is located in the life zone in the northern region of Seoul as part of an extensive park development plan that the municipal government has promoted. The space configuration technique of the aesthetics of "Empty" rather than "Full" gives the potentiality to cope with the uncertain changes in the city. Furthermore, the traditional element of the mountain landscape of Seoul was introduced and appropriated as the axis of the landscape for landscape configuration. In that configuration, the images of tree, sky, wind, water and soil are elegantly unfolded like a landscape painting. The purpose was to create a dominant landmark in the city landscape with the figures of Korean mountains and hills which were differentiated from architectural landmarks in the western cities by making nature, which was excluded from the urbanization plans up to now, an important subject for consideration. As a result, this study madethe space in a park including existing yards and streets in a city have the traditional hierarchy by applying the facility arrangement technique and elements extracted from Korean space types and traditional landscape concepts. Moreover, the North Seoul Dream Forest was designed by pursuing diversity and potentiality in the experience of space using a large open field in a city.