• Title/Summary/Keyword: 완충기능

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Development of a Stance Phase Control Transfemoral Prosthesis Using the 5-Axes Link (5축 링크를 이용한 입각기 제어 대퇴의지의 개발)

  • 김신기;홍정화;김경훈;문무성;이순걸;백영남
    • Journal of Biomedical Engineering Research
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    • v.22 no.1
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    • pp.29-34
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    • 2001
  • 본 연구의 목적은 대퇴부가 절단된 다리의 생체 역학적 기능을 복구할 수 있게 하는 의지의 개발을 위하여 5축 링크, 슬관절 완충장치를 사용하여 보행시 입각기를 제어할 수 있는 대퇴 의지 시스템 개발에 있다. 이를 위하여 입각기시 대퇴의지와 지면간 접촉 중 충격 에너지 흡수를 하는 슬관절 완충장치의 기계적 특성 및 거동을 분석하였다. 임상시험을 통하여 개발된 대퇴의지의 성능을 검증한 결과 대퇴 절단 피검자들의 보행특성은 정상인의 보행에 근접한 경향을 보였다. 결론적으로 본 연구에서 개발된 입각기 대퇴의지는 입각기시 현저한 보행 안전성을 보였다.

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Thermal Effects on the Physicochemical Properties of Domestic Bentonite as a Buffer Material of Spent Fuel Repository (사용후핵연료 처분장 완충재로서 국산벤토나이트의 물리화학적 특성에 대한 열적효과)

  • Park, Jong-Won;Whang, Joo-Ho;Chun, Kwan-Sik;Lee, Byung-hun
    • Nuclear Engineering and Technology
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    • v.23 no.4
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    • pp.456-464
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    • 1991
  • To investigate the thermal effects on functional properties of domestic bentonite, XRD patterns, TG /DSC curves, swelling rates and distribution coefficients of heat-treated Dong-Hae A bentonite were studied. In the XRD patterns, (001) peak disappeared at above 20$0^{\circ}C$ and Dong-Hae A was identified as Ca-bentonite through the DSC curve. The loss of swelling capacity and CEC began at 10$0^{\circ}C$. The distribution coefficients of Am-241, Co-60 and Cs-137 onto heat-treated Dong-Hae A showed negligible variance as temperature was raised and that of Sr-85 decreased at about 15$0^{\circ}C$. Reviewing these data, it was evaluated that Dong-Hae A colud be used as a buffer material at below 10$0^{\circ}C$.

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The Impact of Psychosocial Protective and Risk Factors on Problem Drinking among American Adolescents: Focused on Compensatory and Buffering Effects of Protective Factors (미국 청소년의 문제성 음주에 대한 심리사회적 보호변인과 위험변인의 역할 - 보호변인의 보상효과와 완충효과를 중심으로 -)

  • Kim, Young-Mi
    • Korean Journal of Social Welfare
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    • v.56 no.4
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    • pp.269-290
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    • 2004
  • The purpose of this study was to examine the impact of psychosocial protective and risk factors on problem drinking among American adolescents. In addition, this study investigated the compensatory and buffering effects of psychosocial protective factors. The sample consisted 4,362 10th graders taken from the Monitoring the Future Study 2002. This study performed the hierarchical regression analysis for data analyses. The main findings provided that friend influence, sensation-seeking, and tolerance of deviance had significant positive relationships with problem drinking as risk factors. This study also revealed that negative perception on drinking, parental bonding, school bonding, and prosocial activity had significant direct impacts in decreasing problem drinking, which explains the compensatory effect of protective factors. Additionally, this study showed that negative perception on drinking had a significant buffering effect moderating friend influence on adolescents' opportunities exposed to problem drinking. The results of this study suggest some practical implications for preventive intervention programs that target adolescent problem drinking.

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Convergence Study on the Relationship between Emotional Labor and Burnout in Early Childhood Teachers : The Buffering Effect of Goal-Focused Self-Regulation (유아교사의 감정노동과 직무소진에 있어 목표중심 자기조절의 완충역할에 대한 융합연구)

  • Chung, Myung-Sun
    • Journal of the Korea Convergence Society
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    • v.8 no.6
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    • pp.291-297
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    • 2017
  • As part of the target-specific convergence study of welfare focusing on the relationships between emotional labor, burnout, and goal-focused self-regulation, this study was designed to examine whether goal-focused self-regulation of the early childhood teachers buffers in the relation between emotional labor and burnout. A total of 231 childcare teachers participated in this study and by responding to a questionnaire including measures of emotional labor, burnout, and goal-focused self-regulation. Moderated multiple regression through simultaneously entry was performed for analysis using SPSS (PASW) 18.0 and PROCESS Macro for SPSS. First, the results indicated that the level of emotional labor increase, burnout of the early childhood teachers also increase. Second, goal-focused self-regulation was found to have a protective function in terms of buffering the negative effect of emotional labor on burnout. Based on the results, this study suggests the importance of mental healthcare and the need for internal resources development such as self-regulation.

Planting Evaluations for the Landscaping Tree and Application Plan by Assessment Grade in the City Park - A Case Study of Haedoji Park, Songdo, Incheon Metropolitan City - (도시공원 조경수목 식재 평가 및 평가등급 적용 방안 - 인천광역시 송도 해돋이공원을 대상으로 -)

  • Han, Bong-Ho;Cho, Hun-Gum;Kwak, Jeong-In;Park, Seok-Cheol
    • Korean Journal of Environment and Ecology
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    • v.28 no.4
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    • pp.457-471
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    • 2014
  • This study aims to present an evaluation scheme to improve the problems in tree shapes and tree growth which were identified through shape and growth assessments of landscape trees currently planted in Haedoji Park, Songdo, Incheon Metropolitan City after plant structure status and propriety review for funtion of space and concept of planting. Suitability the planting concept was evaluated according to function of space. The result indicated that the shade planting areas accounted for 29.5% of the the shade spaces area. 58.7%, respectively planting areas of visual landscape. And 11.8%, respectively planting areas of buffer. Because the planting areas was lacked according to the park established spatial configuration of central facilities and the result of plant young trees. Plant structure status required consideration with plant structure, density, size, growth status for improve planting function. The tree assessment was performed on a total of 28 species and 600 trees of which 22 species and 209 trees were planted in the buffer zone, 8 species and 71 trees in the shade zone, 16 species and 266 trees in the visual landscape zone, and 4 species and 54 trees in the ecological landscape zone. The trees were divided into grades based on their assessment score and were statistically grouped by the functional zone in where they are planted and by tree species to verify their significance. The tree shape assessment was an average of 56.6 points and the tree growth assessment was an average of 76.0 points. Using the results of the tree assessments, the tree standards for each functional space were identified and a concept of optimum planting and cultivating was applied. When applying the shape assessment results by zone to the concept of planting, since trees for buffering require high functionality they received E's, the lowest grade; as trees for ecological landscaping require diverseness and naturalness, they received D's; since trees for shading require utilization, they received C's as trees with branching at the main stems were considered; and since trees for visual landscaping required aesthetical value, they received A's and B's. When applying the growth assessment results by zone to the concept of planting, based on planting foundations of favorable and poor, for buffering, visual landscaping, and ecological landscaping, trees from grades A to E could be planted, and for shading, trees from grades A to C could be planted. For a cultivation plan that could improve the growth of the trees, we proposed that the topography of the land be selected considering the tree's characteristics and that a method of pot seeding be used. Also, to improve the shape of the trees, we proposed that poles be used to improve the growth of vertically-straight stems, an appropriate planting density be applied for reasonable branch growth, manage tree shape to maintain good crowning, and better manage fertilization to maintain a reasonable crown density.

A Prediction of Saturated Hydraulic Conductivity for Compacted Bentonite Buffer in a High-level Radioactive Waste Disposal System (고준위방사성폐기물 처분시스템의 압축 벤토나이트 완충재의 포화 수리전도도 추정)

  • Park, Seunghun;Yoon, Seok;Kwon, Sangki;Kim, Geon-Young
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.2
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    • pp.133-141
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    • 2020
  • A geological repository comprises a natural barrier and an engineered barrier system. Its design components consist of canisters, buffers, backfill, and near-field rock. Among the engineered barrier system components, bentonite buffers minimize the groundwater flow from near-field rock and prevent the release of nuclide. Investigation of the hydraulic conductivity of the buffer to groundwater flow is an important factor in the performance evaluation of the stability and integrity of the engineered barrier of the repository. In this study, saturated hydraulic conductivity tests were performed using Gyeongju bentonite at various dry densities and temperatures, and a hydraulic conductivity prediction model was developed through multiple regression analysis using the 120 result sets of hydraulic conductivity. The test results showed that the hydraulic conductivity tends to decrease as the dry density increases. In addition, the hydraulic conductivity increased with increasing temperature. The multiple regression analysis results showed that the coefficient of determination (R2) of the hydraulic conductivity prediction equation was as high as 0.93. The hydraulic conductivity prediction equation presented in this study could be used for the design of engineered barrier systems.

Research on Landscape Plan Strategy of Urban Waterside Space Buffer Zone - Focused on the Case of the Resilient Perspective of Plan - (도시 수변 완충지역의 경관 계획에 관한 연구 - 탄성 (resilient) 관점의 계획 사례분석을 중심으로 -)

  • Yang, Meng;Hong, Kwan-Seon
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.404-416
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    • 2020
  • Flooding is an unavoidable natural disaster for the city. Flood disasters seriously undermine the city's economy, safety, and sustained development. In the course of development and construction of waterfront space in the same city, the construction of basic disaster prevention facilities cannot be avoided completely even if huge amounts of capital are invested to reduce the economic damage of flooding. The cost of rebuilding the city after the disaster is much higher than the cost of building disaster prevention facilities. In recent years, the theory of elasticity in urban reconstruction and so on has been a subject of city problem solving, creating widespread discussion and attention in academia. In other words, how to transform the concept of elasticity into practice based on theoretical and empirical factors is a real problem facing urban disaster. Through theoretical literature on the waterfront (space) buffer zone of a city (flood-weak area) and the case study of the city's practice, this paper tries to clarify the element of 5R, the theory of elastomeric fire prevention, and present detailed measures accordingly. In addition, the following two problems are addressed while emphasizing the feasibility of implementing the urban waterfront (space) plan of the elastomeric element around the urban water buffer zone. First, the means of disaster prevention planning are used to mitigate conflicts between individual utility of urban waterfront and disaster prevention functions in waterfront buffer zones, and second, the waterfront buffer zone can respond to flood-causing problems in terms of disaster prevention as much as possible through the elastic disaster prevention plan.

pH Dependence on EC in Soils Amended with Fertilizer and Organic Materials and in Soil of Plastic Film House (비료와 퇴구비를 처리한 토양과 시설재배지 토양에서 토양의 EC에 따른 pH변화)

  • Kim, Yoo-Hak;Kim, Myeong-Sook;Kwak, Han-Kang
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.5
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    • pp.247-252
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    • 2005
  • Soil pH is an intensity factor of releasing hydrogen ion which is buffered by aluminum. It depends on pH buffer capacity of Al whether soil pH is governed directly by cations or not. A study was conducted to elucidate the pattern of pH changes by soil EC. Fertilizer and three kinds of organic manures composed of cow and pig and fowl dropping and one kind of rice straw compost were added independently into upland sandy loam soil. This treated soils and four upland soils under plastic film house having different levels in electrical conductivity (EC) were incubated with field capacity at $30^{\circ}C$ for 5, 10, 20 and 40 days. Soil pH varied directly as the cations contained in organic materials according to degree of saturating pH buffer capacity (pBC) of sandy loam soil. pH of the soils under plastic film house was lowered by soil EC due to governing by overplus of cation beyond pBC.

A Study on the Direction of Planting Renewal in the Green Area of Seoul Children's Grand Park Reflecting Functional Changes (기능변화를 반영한 서울어린이대공원 조성녹지의 식재 리뉴얼 방향성 연구)

  • Park, Jeong-Ah;Han, Bong-Ho;Park, Seok-Cheol
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.3
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    • pp.21-36
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    • 2023
  • As a solution to environmental issues, such as climate change response, the carbon neutrality strategy, urban heat islands, fine dust, and biodiversity enhancement, the value of urban green spaces and trees are becoming important, and various studies dealing with the effects of trees for environmental improvement are being conducted. This study comprehensively considers the preceding studies on planting tree species, planting structure, planting density, and planting base to propose a direction for the planting renewal of green areas in urban parks and applies the findings to a renewal plan to improve the urban environment through landscaping trees. A field survey was conducted on the planting status of Seoul Children's Grand Park, a large-scale neighborhood park in Seoul, and based on the survey data, a planting function evaluation was conducted, and areas needing improvement in planting function were identified. The planting function evaluation was carried out considering the park function setting, planting concept according to spatial function, and planting status. As a result of the study, the direction of planting renewal according to functional change was derived for each stage of planting function evaluation. Increasing the green area ratio is a priority in setting up park functions, but user convenience should also be considered. As a concept of planting, visual landscape planting involves planting species with beautiful tree shapes, high carbon absorption, and fine dust reduction effects. Ecological landscape planting should create a multi-layered planting site on a slope. Buffer planting should be created as multi-layered forests to improve carbon absorption and fine dust reduction effects. Green planting should consist of broad-leaved trees and herbaceous layers and aim for the natural planting of herbaceous species. For plant species, species with high urban environment improvement effects, local native species, and wild bird preferred species should be selected. As for the planting structure, landscape planting sites and green planting sites should be composed of trees, shrubs, and trees and herbaceous layers that emphasize ecology or require multi-layered buffer functions. A higher standard is applied based on the planting interval for planting density. Installing a rainwater recycling facility and using soil loam for the planting base improves performance. The results of this study are meaningful in that they can be applied to derive areas needing functional improvement by performing planting function evaluation when planning planting renewal of aging urban parks and can suggest renewal directions that reflect the paradigm of functional change of created green areas.

Design of Riparian Buffer Zone by Citizen's Participation for Ecosystem Service - Case Study of Purchased Land along Gyeongan-cheon in Han River Basin - (생태계 서비스를 위한 주민 참여형 수변완충녹지 설계 고찰 - 한강수계 경안천변 매수토지 사례 연구 -)

  • Bahn, Gwon-Soo
    • Journal of Wetlands Research
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    • v.24 no.3
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    • pp.170-184
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    • 2022
  • The Riparian Buffer Zone(RBZ) is a sustainable social-ecological system created in the middle zone between water and land. For the RBZ, close communication with the local community is important, and it is necessary to promote it as a communicative environmental planning process. In this study, for the RBZ project, three strategies are presented as a communicative act to understand and implement planning. First, government-led projects were avoided and improved to a process in which citizens and stakeholders participated together, centered on local partnership. Second, it was intended to introduce design criterias in terms of enhancing the function of ecosystem services that citizens can sympathize with, and to increase acceptance and awareness through the planning of preferred spaces and facilities. Third, after a balanced plan for habitats, water cycle-based ecological environment, ecological experience and open space, citizens felt the restoration effect and value as an ecological resources, and a system was prepared to participate in the operation and management. This study will work as a process model based on citizens's participation. In addition, it will be possible to provide lessons for the change of the policy paradigm for the RBZ and the implementation of similar projects in the future.