• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.6
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• pp.98-108
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• 2015

The purpose of this study is to analyze the effect of neighborhood environmental perception on park use for health. The study area is focused on neighborhood parks in Suseong-gu, Daegu city. The analysis results are based on questionnaires of 303 respondents. According to the results, park use for health improvement was significantly associated with the perceptions of accessibility to a marketplace, availability of public transit, accessibility to the park, enough sidewalks, number of crosswalks, and athletic population. The probability of park use increased by 2.326 times as the satisfaction of accessibility to the park increased. Also, greater athletic population, fewer crosswalks, and more sidewalks lead to increase of park use by 1.701, 1.617, and 1.642 times, respectively. Therefore, it is important to increase the available neighborhood parks around residences and to develop exercise programs that people can use continuously in order to vitalize park use for health improvement. Also, it is necessary to improve the convenience of walking such as development of pedestrian streets or malls between residences and parks.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.43-50
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• 2012

The Green Infrastructure Framework refers to an interconnected network formed by greenways that links gardens, parks, green spaces, streams, wetlands, agricultural lands, and green belts. Green infrastructure supports diverse functions to environment, provides various benefits to people, and helps in the community's health and viability. It can store stormwater runoff and abate its non-point source pollutants. Due to its advantages and profits, advanced countries in environment policies have adopted green infrastructure in planning and implementing urban and regional development. The Korean government and municipalities have focused upon grey infrastructure investment in the past, which causes occurrence of natural disasters such as draught, flood, and landslides, degradation of water and air quality, decline of biodiversity, and even inhibition of economic activities. In order to alleviate these problems, it is requested to formulate and implement policies for green infrastructure at the national government level. USA and Korean situation of green infrastructure were investigated; forty components of green infrastructure were drawn. Nine policies utilized in the USA cases were identified, which are applicable to Korea. Among them, five policies can be implemented in public sector and four in private one. The green infrastructure law needed in Korea was suggested. The amendments of laws regarding green infrastructure and alternatives expending it were proposed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1055-1067
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• 1994

This paper is presented to perform linear dynamic analysis of bridges due to vehicle moving on bridges. The road surface roughness and bridge/vehicle interaction are also considered. The bridge and vehicle are modeled as 3-D bridge and vehicle model, respectively. The road surface roughness of the roadway and bridge decks are generated from power spectral density(PSD) function for good road. The PSD function proposed by C.J. Dodds and J.D. Robson is used to describe the road surface roughness for good road condition. The vehicles are modeled as two nonlinear vehicle model with 7-D.O.F of truck and 12-D.O.F of tractor-trailer and the equations of motion of the vehicles are derived using Lagrange's equation. The main girder and concrete deck are modeled as beam and shell element, respectively and rigid link is used between main girder and concrete deck. The equations of motion of the vehicles are solved by Newmark ${\beta}$ method and the equations of the motion of the bridges are solved by mode-superposition procedures. The validity of the proposed procedure is demonstrated by comparing the results with the experimental data reported by the AASHO Road Test. The comparison shows that the agreement between experiment and theory is quite satisfactory.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.444-449
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• 1995

한국형 표준 원자력발전소의 정지냉각운전시 최대냉각율은 75$^{\circ}$F/hr(41.7$^{\circ}C$/hr)로 기술사양서에 규정되어 있다. 정지냉각운전 냉각율에 가장 큰 영향을 미치는 2가지 중요한 변수는 정지냉각계통 열교환기를 지나는 원자로냉각재 유량과 기기냉각수의 온도다. 이중 열교환기를 지나는 원자로냉각재 유량은 butterfly형 정지냉각계통 유량조절밸브의 개도에 의하여 조절되는데 개도에 따른 throttle 능력이 중요한 인자다. 또 기기냉각수의 온도는 해수온도의 변화에 따라 편차가 발생하므로 유량조절밸브의 개도와 기기냉각수 온도의 상관관계에 따라 냉각능력이 달라진다. 본 논문에서는 현 울진 3&4호기 정지냉각계통 열 교환기 및 조절밸브 둥의 설비를 기준으로 기술사양서 상의 냉각율 75$^{\circ}$F/hr(41.7$^{\circ}C$/hr) 유지가 가능한 최저 기기냉각수의 온도를 찾아보았고, 아울러 기기냉각수의 온도와 조절밸브의 개도 사이의 관계를 조사하였다. 그 결과 현재의 울진 3&4호기 조절밸브를 최저개도로 조절할 때 약 57$^{\circ}$F(13.9$^{\circ}C$)의 기기냉각수가 공급되어도 냉각율 제한치를 넘지 않는 것으로 분석되었다. 한편, 최저조절가능 유량이 약 2000 gpm(7570 l/min)일 경우에는 낮은 기기냉각수가 공급될 경우 최대냉각율을 초과하므로 한 train을 정지시키고 한 train만으로 운전할 것을 고려하여야 할 것으로 보인다. 이 경우 최저 약 56.5$^{\circ}$F(13.6$^{\circ}C$)의 기기냉각수가 공급되어야 한다. 본 논문의 분석결과는 향후 기기설계사양서나 운전지침서 등에 반영되어 실제 발전소 설계 및 운전절차 수립에 기여할 수 있을 것으로 생각된다.공감대의 형성이 요구된다. 질적 측면에서는 공원 녹지의 기능성의 회복이라는 측면과 시대에 부합되는 새로운 기능 및 가치의 부여가 필요하며, 이를 위해서는 공원의 매력, 공원의 시설기능 증진, 녹지의 질의 향상 및 녹지 가치의 증진에 대한 다양한 시책이 요구된다. 구성적 측면에서는 공원녹지의 개별적 존재보다는 공원 녹지를 상호간 유기적인 계통을 확보하여 공원 녹지의 네트워크를 형성하여 도시 속의 산재된 고립된 섬으로서의 공원 녹지가 아닌 시민생활에 늘 가까이 있는 생활 속의 공원녹지로 재편되어야 한다. 이러한 정책의 의제는 양적 측면에서 보전(CONSERVATION)과 창출(CREATION), 질적 측면에서 쇄신(RENOVATION)과 복구(RESTORATION), 그리고 구성적 측면에서 공원 녹지의 연결(CONNECTION)과 시민 참여에 의한 운동(MOVEMENT)이라는 정책 개념의 구현을 통해 가능하다. 이러한 정책 개념과 의제를 가지고 서울시 공원 녹지 정책을 구체화시키기 위해서 푸르름의 새로운 탄생이라는 기치 아래 풍요로운 서울, 사랑 받는 공원, 생활 속의 녹지의 3대 목표, 공원 녹지의 보전, 잠재 공원 녹지의 창출, 공원의 활성화, 녹지의 복구, 경관 보전 및 복구, 공원 녹지의 네트워크, 도시 녹화의 7대 과제를 설정하고 미시설 공원 녹지 집행, 개발 사업시 공원 녹지의 확보, 환경 녹지의 총량 보호 관리, 도시 소공원 개발, 역사 문화 공원 조성, 하천 공간 복원, 공원 시설 기능 개선, 이용 프로그램 개발, 공원 관리 개선, 환경 피해 녹지의 회복, 도시 환경 림 조성, 녹지 기능 증진, 도시 자연 경관 보전, 공원 녹지체계 구성, 공원 녹지 공급 균형, 주변 환경 녹화, 가로 녹화의 17개 시책을 제안하였다. 이러한 정책사업의 원활한 추진을 위해서는 기존의 관주도의 일방적인 공원 녹지 행정이 아닌 시민의 참여를 통한 시민이 함께 하는 정 책 사업의 추진이 요구되며, 특히 민간 부문의

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.3
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• pp.202-208
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• 2017

The recently developed marine engines for propulsion of ships have higher torsional exciting force than previous engines to improve the propulsion efficiency and to reduce specific fuel oil consumption. As a result, a viscous damper or viscous-spring damper is installed in front of marine engine to control the torsional vibration. In the case of viscous damper, it is supposed that there is no elastic connection in the silicon oil, which is filled between the damper housing and inertia ring. However, In reality, the silicon oil with high viscosity possesses torsional stiffness and has non-linear dynamic characteristics according to the operating temperature and frequency of the viscous damper. In this study, the damping characteristics of a viscous damper used to control the torsional vibration of the shafting system have been reviewed and the characteristics of torsional vibration of the shafting system equipped with a corresponding viscous damper have been examined. In addition, it is examined how to interpret the theoretically optimal dynamic characteristics of a viscous damper for this purpose, and the optimum design for the propulsion shafting system has been suggested considering the operating temperature and aging. when the torsional vibration of the shafting system is controlled by a viscous damper filled with highly viscous silicon oil.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.35-40
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• 1978

The uptake ratio of supplying $P^{32}$ labelled double superphosphate and the hastening efficiency of the uptake by addition of magnesium sulfate to the fertilizer were studied on the ${\times}Populus $ albaglandulosa planted with 0/1 cutting in 1975. The results are summerized as follows. 1. Average 13% of supplying double superphosphate was absorbed into ${\times}Populus$ albaglandulosa planted on the reddish heavy clay soil in Institute of Forest Genetics. 2. The accumulation of absorbed magnesium was more amount in leaf than in stem. 3. The uptake ratio of supplying double superphosphate was able to increase up to 16%~33% by the addition of magnesium sulfate to the fertilizer. 4. It might be possible to increase the tree growth following the acceleration of photosynthesis due to the increasing amount of magnesium known to be a component of chlorophyll in leaf as well as to hasten the efficiency of uptake of phosphorus by the addition of magnesium to double superphosphate.

• Applied Microscopy
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• v.31 no.2
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• pp.207-214
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• 2001

Anatomy and ultrastructure of the modifeid Krana pattern have been studied in succulent Salsola collina Pall. Cylindrical leaves exhibited the Salsoloid Kranz type containing two layers of peripheral chlorenchyma that surrounded the water storage cells and vascular tissues. Small veins were also peripherally arranged, but mostly embedded in the vicinity of the inner chlorenchma without the orderly arrangement of the concentric layering of bundle sheath and mesophyll cells. The current study mainly focused on the chlorenchyma tissue abutting such minor veins. The outer columnar layer exhibited features similar to the characteristics of palisade mesophyll cells, while the inner cuboid layer to the bundle sheath cells of a typical $C_4$ Kranz pattern. Cellular components of the inner chlorenchyma were centripetal and numerous, but starch-laden chloroplasts were rudimentary in the thylakoidal system. The outer chlorenchyma demonstrated normally developed chloroplasts having well-stacked thylakoids and plastoglobuli. Branched and complicated plasmodesmata frequently occurred in thick interfaces of the two layers, implying the active movement of the photosynthates between them. The present data were mostly congruent with one of the structural features of the C4 subtypes , NADP-ME type, reported in the $C_4$ pattern. The Kranz pattern encountered in this Salsola probably has been directly related to the structural modification that occurred during a functional adaptation to the $C_4$ photosynthesis.

• Journal of Educational Research in Mathematics
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• v.16 no.4
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• pp.367-386
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• 2006

There are two strands for considering tile relationships between education and technology. One is the viewpoint of 'learning from computers' and the other is that of 'learning with computers'. In this paper, we call mathematics education with computers as 'computers and mathematics education' and this computer environments as microworlds. In this paper, we first suggest theoretical backgrounds ai constructionism, mathematization, and computer interaction. These theoretical backgrounds are related to students, school mathematics and computers, relatively As specific strategies to design a microworld, we consider a physical construction, fuctiionization, and internet interaction. Next we survey the different microworlds such as Logo and Dynamic Geometry System(DGS), and reform each microworlds for mathematical level-up of representation. First, we introduce the concept of action letters and its manipulation for representing turtle actions and recursive patterns in turtle microworld. Also we introduce another algebraic representation for representing DGS relation and consider educational moaning in dynamic geometry microworld. We design an integrating microworld between Logo and DGS. First, we design a same command system and we get together in a microworld. Second, these microworlds interact each other and collaborate to construct and manipulate new objects such as tiles and folding nets.

• School Mathematics
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• v.9 no.1
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• pp.119-139
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• 2007

The purpose of this study is to analyze students' misconception in the teaming of the conic sections with the cognitive and pedagogical point of view. The conics sections is very important concept in the high school geometry. High school students approach the conic sections only with algebraic perspective or analytic geometry perspective. So they have various misconception in the conic sections. To achieve the purpose of this study, the research on the following questions is conducted: First, what types of misconceptions do the students have in the loaming of conic sections? Second, what types of errors appear in the problem-solving process related to the conic sections? With the preliminary research, the testing worksheet and the student interviews, the cause of error and the misconception of conic sections were analyzed: First, students lacked the experience in the constructing and manipulating of the conic sections. Second, students didn't link the process of constructing and the application of conic sections with the equation of tangent line of the conic sections. The conclusion of this study ls: First, students should have the experience to manipulate and construct the conic sections to understand mathematical formula instead of rote memorization. Second, as the process of mathematising about the conic sections, students should use the dynamic geometry and the process of constructing in learning conic sections. And the process of constructing should be linked with the equation of tangent line of the conic sections. Third, the mathematical misconception is not the conception to be corrected but the basic conception to be developed toward the precise one.

• Journal of Life Science
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• v.27 no.7
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• pp.840-848
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• 2017

Proper intracellular transport is essential for normal cell function. Intracellular transport is mediated by microtubule-dependent molecular motor proteins, as well as kinesin and cytoplasmic dynein, which move their cargo along long, microtubule tracks in cells. Kinesins are ATP-dependent plus-end-directed motor proteins in the intracellular transport of organelles, vesicles, RNA complexes, and protein complexes. The mislocalization of these different types of cargo has been linked to cell dysfunction and degeneration. The cargo transport of kinesins can be described by the following steps: binding to the appropriate cargo and/or adaptor proteins, activation of the kinesin's motility and movement along the microtubule, and the release of the cargo at the correct destination. Recently, several studies have revealed the mechanisms for the regulation of kinesin motor activity, including cargo loading and unloading. Intracellular cargo transport is also modulated by adaptor proteins, which link the kinesins to their cargo. The regulatory proteins, which include protein kinases and phosphatases, regulate kinesin motor activity directly through the phosphorylation or dephosphorylation of kinesins and indirectly through the modification of adaptor proteins, such as c-Jun NH-terminal kinase-interacting proteins, or of the microtubule network. These findings lay the groundwork for understanding how kinesins are differentially engaged in intracellular cargo transport. In addition, understanding the regulatory mechanisms of each kinesin is an area of key interest within cell biology and neurophysiology. In this study, we reviewed kinesins' regulation proteins and discuss how their regulation affects cargo recognition and transport.