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A Study on the Effect of the Changes of Play Facilities on Rules Changes - Focusing on the City of Seoul - (관련법규 변천이 아파트단지 내 어린이놀이터 변화에 미치는 영향 연구 - 서울시 소재 현장을 중심으로 -)

  • Kim, Dong-Chan;Suh, Joo-Hwan;Park, You-Jeong
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.2
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    • pp.26-35
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    • 2009
  • This study is an analysis of the design changes of children's play facilities and the related rules and regulations which causes these changes. Accordingly, it is noticed that a site's change of design by legislation and by yearly alternation influences playground design. First, after revising the provisions for the distance from roads and parking lots, the constructing of safety fences between play facilities and the using of durable materials, alterations of the designs have been made a reality. Second, the design changes after the period of regulation transitions were caused by provisions related to the shelter of evergreens and conditions of the sun. Third, the changes of the playgrounds were related to the substitution of exercise facilities for the local residents and in carrying out a hygiene exam more than twice a year. Because a lack of regulatory standards for the design of playgrounds resulted in compliance based on individual interpretation and because a substitution of exercise facilities is part of the way to alleviate these regulations, the conditions of the site under investigation could be projeced. By such changes of regulations and analysis of alterations of playground design, programs for improvement were suggested. It turned out that the composition of the concrete standard in conformity with regulations required closer observance. Moreover, design standards for children's playgrounds are needed, such as the provision of variation in external appearance, the creation of more flexible layouts and the outlining of spaces by themes.

Channel Model and Wireless Link Performance Analysis for Short-Range Wireless Communication Applications in the Terahertz Frequency (테라헤르츠 대역 주파수에서 근거리 무선 통신 응용을 위한 채널 모델 및 무선 링크 성능 분석)

  • Chung, Tae-Jin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.9
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    • pp.868-882
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    • 2009
  • In this paper, channel model and wireless link performance analysis for the short-range wireless communication system applications in the terahertz frequency which is currently interested in many countries will be described. In order to realize high data rates above 10 Gbps, the more wide bandwidths will be required than the currently available bandwidths of millimeter-wave frequencies, therefore, the carrier frequencies will be pushed to THz range to obtain larger bandwidths. From the THz atmospheric propagation characteristics based on ITU-R P.676-7, the available bandwidths were calculated to be 68, 48 and 45 GHz at the center frequencies of 220, 300 and 350 GHz, respectively. With these larger bandwidths, it was shown from the simulation that higher data rate above 10 Gbps can be achieved using lower order modulation schemes which have spectral efficiency of below 1. The indoor propagation delay spread characteristics were analyzed using a simplified PDP model with respect to building materials. The RMS delay spread was calculated to be 9.23 ns in a room size of $6\;m(L){\times}5\;m(W){\times}2.5\;m(H)$ for the concrete plaster with TE polarization, which is a similar result of below 10 ns from the Ray-Tracing simulation in the reference paper. The indoor wireless link performance analysis results showed that receiver sensitivity was $-56{\sim}-46\;dBm$ over bandwidth of $5{\sim}50\;GHz$ and antenna gain was calculated to be $26.6{\sim}31.6\;dBi$ at link distance of 10m under the BPSK modulation scheme. The maximum achievable data rates were estimated to be 30, 16 and 12 Gbps at the carrier frequencies of 220, 300 and 350 GHz, respectively, under the A WGN and LOS conditions, where it was assumed that the output power of the transmitter is -15 dBm and link distance of 1 m with BER of $10^{-12}$. If the output power of transmitter is increased, the more higher data rate can be achieved than the above results.

Development of Solar Warehouse for Drying and Storing the Agricultural Products (농산물(農産物) 건조(乾燥) 및 저장(貯藏)을 위(爲)한 태양열(太陽熱) 저장고(貯藏庫)의 개발(開發)에 관(關)한 연구(硏究))

  • Kim, Man Soo;Chang, Kyu Seob;Kim, Soung Rai;Jeon, Byeong Seon
    • Korean Journal of Agricultural Science
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    • v.9 no.1
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    • pp.357-370
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    • 1982
  • Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.

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A Study on Establishment for Archival Management and Training of Archivists (기록관리학의 정립과 기록전문가 양성교육에 관한 연구)

  • Choe, Jung-Tai;Yoon, Song-Won
    • Journal of Korean Society of Archives and Records Management
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    • v.1 no.1
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    • pp.95-129
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    • 2001
  • The treatise is a follow-up thesis of "The Archival Management : destination of its education" published by The Research Institute for Korean Archives and Records in June 17, 2000, and it was written to secure its original temper of the "Archival Management" which has established at first as the domestic collegiate educational course. Presently, we are mixed up for interpretation of terminology by facing unfamiliar words: such as, Archives, Documents, Manuscripts, Records / Archival Management, Archival Preservation / Archivist, Archival Conservator, Manuscripts Curator and Record Manager. Also, tile treatise has confirmed scholars' various opinion about its education and curriculum not only domestic but overseas scholars, and examined realities and course of studies of 4 overseas countries, and also have purpose to pursue domestic universities' actual condition of curriculum and its reform measure. And since dispositon of Archivist and the professional organization of the Archivist was based on the Laws, therefore, establishment of an educational institution for Archival Management from now on will be expanded more and need to be accelerated. Accordingly, the universities that already established or to be established from now on, shall be needed educational quality and its contents to be ascended. Its concrete plan is as follows : (1) Now, disarranged archive and record words, and to make publish 'Glossary of Archives & Records' as soon as possible. (2) Remind the substance of the Record and Archival Management and its sphere again and need to be considered alteration of the studies' name. (3) There needs to establish the role and establishment of conception of Archivists. (4) Refer to the theory and practical educational method of overseas professional Archivist Scholars, but to be needed to develop the curriculum which is accorded with am tradition and way of thinking. (5) Confer for development of teaching materials and educational method jointly through 'Academic Society', and there needs reorganize the subject which is fit for each university's characteristics. (6) Recently, "Cultural Resources Studies" for research specialization which has established in Graduate School of Tokyo University was very useful to us. We also need to be considered such establishment of process.

Land Cover Classification of Coastal Area by SAM from Airborne Hyperspectral Images (항공 초분광 영상으로부터 연안지역의 SAM 토지피복분류)

  • LEE, Jin-Duk;BANG, Kon-Joon;KIM, Hyun-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.1
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    • pp.35-45
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    • 2018
  • Image data collected by an airborne hyperspectral camera system have a great usability in coastal line mapping, detection of facilities composed of specific materials, detailed land use analysis, change monitoring and so forh in a complex coastal area because the system provides almost complete spectral and spatial information for each image pixel of tens to hundreds of spectral bands. A few approaches after classifying by a few approaches based on SAM(Spectral Angle Mapper) supervised classification were applied for extracting optimal land cover information from hyperspectral images acquired by CASI-1500 airborne hyperspectral camera on the object of a coastal area which includes both land and sea water areas. We applied three different approaches, that is to say firstly the classification approach of combined land and sea areas, secondly the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas, and thirdly the land area-only classification approach using atmospheric correction images and compared classification results and accuracies. Land cover classification was conducted respectively by selecting not only four band images with the same wavelength range as IKONOS, QuickBird, KOMPSAT and GeoEye satelllite images but also eight band images with the same wavelength range as WorldView-2 from 48 band hyperspectral images and then compared with the classification result conducted with all of 48 band images. As a result, the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas is more effective than classification approach of combined land and sea areas. It is showed the bigger the number of bands, the higher accuracy and reliability in the reclassification approach referred above. The results of higher spectral resolution showed asphalt or concrete roads was able to be classified more accurately.

Deterioration Diagnosis and Source Area of Rock Properties at the West Stone Pagoda, Gameunsaji Temple Site, Korea (감은사지 서탑의 풍화훼손도 진단 및 석재의 산지추정)

  • Lee Chan Hee;Lee Myeong Seong;Suh Mancheol;Choi Seok-Won;Kim Man Gap
    • Economic and Environmental Geology
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    • v.37 no.5
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    • pp.569-583
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    • 2004
  • The rock properties of the West pagoda in the Gameunsaji temple site are composed mainly of dark grey porphyritic granodiorite with medium grained equigranular texture and developed with small numerous dioritic xenoliths. These xenoliths occurred with small holes due to different weathering processes. As a weathering results, the rock properties of this pagoda occur wholly softened to physical hardness because of a complex result of petrological, meteorological and biological causes. Southeastern part of the pagoda deteriorated seriously that the surface of rock blocks showed partially exfoliations, fractures, open cavities in course of granular decomposition of minerals, sea water spray and crystallization of salt from the eastern coast. The Joint between blocks has small or large fracture cross each other, contaminated and corrupted for inserting with concrete, cement mortar, rock fragments and iron plates, and partially accelerated coloration and fractures. There are serious contamination materials of algae, fungus, lichen and bryophytes on the margin and the surface on the roof stone of the pagoda, so it'll require conservation treatment biochemically for releasing vegetation inhabiting on the surface and the discontinuous plane of the blocks because of adding the weathering activity of stones and growing weeds naturally by soil processing on the fissure zone. Consisting rock for the conservation and restoration of the pagoda would be careful choice of new rock properties and epoxy to reinforce for the deterioration surfaces. For the attenuation of secondary contamination and surface humidity, the possible conservation treatments are needed.

Sensitivity of NOx Removal on Recycled TiO2 in Cement Mortar (재생 이산화티탄을 혼입한 모르타르의 NOx 저감률 민감도 분석)

  • Rhee, Inkyu;Kim, Jin-Hee;Kim, Jong-Ho;Roh, Young-Sook
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.4
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    • pp.388-395
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    • 2016
  • This paper explores the photocatalytic sensitivity of cement mortar incorporated with recycled $TiO_2$ from waste water sludge. Basically, $TiO_2$ cluster sank down slowly to the bottom of cement mortar specimen before setting and hardening process. This leads the mismatch of $TiO_2$ concentration on the top and the bottom faces of a specimen. This poorly dispersed $TiO_2$-cement mortar naturally exhibits poor NOx removal efficiency especially on the top of cementitious structure. In architectural engineering application such as building or housing structures, one can simply filp over from the bottom so that more $TiO_2$ concentrated surface can be placed outward into the air. However, in highway pavement case, this could not be applicable due to in-situ installation of concrete pavement. Hence, the dispersion of $TiO_2$ cluster inside the cementitous material is getting important issue onto road construction application. To elaborate this issue, according to our results, silica fume, high-ranged water reducer, viscosity agent, blast furnace slag were not enhanced much of dispersion characteristics of $TiO_2$ cluster. The combination of foaming agent and accelerator of hardening with viscosity agent and small grain size of fine aggregate may help the dispersion of $TiO_2$ inside cementitious materials. Even though the enhanced dispersion were applied to the specimen, NOx removal efficiency doest not change much for the top surface of the specimen. This concurrently affected by the presence of tiny air voids and the dispersion of $TiO_2$ in that these voids could easily adsorbed NOx gas with the aid of large surface area.

An Analysis of the Difference in Awareness on Visual Landscape Control Elements among the Expert Groups (경관제어요소에 관한 전문가집단 간 인식차이 분석)

  • Cho, You-Kyung;Kong, Eun-Mi;Kim, Young-Ook
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.2
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    • pp.29-39
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    • 2011
  • Recent interests in the quality of urban space have raised awareness on the role and importance of landscape planning. Although laws and guidelines are officially ready to be imposed as for landscape planning, we do not have concrete materials that can be utilized in the course of practices. The aim of this paper in this regard is to disclose the possible difference in awareness on 'visual landscape control elements' among experts engaged with urban space planning. The expert groups are distinguished to three which are for a planning, design and engineering and the survey is made by questionnaires. The results are analyzed through basic technology statistics in SPSS and independent-sample t-test provided. The survey is done by tens of 'control elements' and the result is that specially, group 1 and group 2 in mixed landscape has the most discrepancy in awareness on those elements but relatively, they has less discrepancy in awareness on compare with other groups through all landscape area. In case of artificial landscape and mixed landscape in 'landscape controled area', the result for comparing between G1 and G2 is that there are the most discrepancy in awareness which are 7 control elements. In case of mixed landscape in 'landscape promoted area', there are 4 control elements for discrepancy in awareness between G2 and G3 which is quite different. The control elements which show the most discrepancy in awareness is height, floor space and building to land ratio in order. The shape elements has only discrepancy in awareness for comparing between G1 and G2 of artificial landscape in 'landscape controled area'. In terms of the average evaluation score of the appropriateness of these control elements, G1 seems to appreciate the role of these elements in systematic landscape planning more than the other group does. In other words, relatively low scores are given by G2 as for the overall functionality of visual landscape control elements. The texture, floor space and building of land ratio has low evaluation score for all area and types. It means that it should reverify for appropriateness of performance for landscape planning as visual landscape control elements.

Three Teaching-Learning Plans for Integrated Science Teaching of 'Energy' Applying Knowledge-, Social Problem-, and Individual Interest-Centered Approaches (지식내용, 사회문제, 개인흥미 중심의 통합과학교육 접근법을 적용한 '에너지' 주제의 교수.학습 방안 개발(II))

  • Lee, Mi-Hye;Son, Yeon-A;Young, Donald B.;Choi, Don-Hyung
    • Journal of The Korean Association For Science Education
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    • v.21 no.2
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    • pp.357-384
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    • 2001
  • In this paper, we described practical teaching-learning plans based on three different theoretical approaches to Integrated Science Education (ISE): a knowledge centered ISE, a social problem centered ISE, and an individual interest centered ISE. We believe that science teachers can understand integrated science education through this paper and they are able to apply simultaneously our integrated science teaching materials to their real instruction in classroom. For this we developed integrated science teaching-learning plans for the topic of energy which has a integrated feature strongly among integrated science subject contents. These modules were based upon the teaching strategies of 'Energy' following each integrated directions organized in the previous paper (Three Strategies for Integrated Science Teaching of "Energy" Applying Knowledge, Social Problem, and Individual Interest Centered Approaches) and we applied instruction models fitting each features of integrated directions to the teaching strategies of 'Energy'. There is a concrete describing on the above three integrated science teaching-learning plans as follows. 1. For the knowledge centered integration, we selected the topic, 'Journey of Energy' and we tried to integrate the knowledge of physics, chemistry, biology, and earth science applying the instruction model of 'Free Discovery Learning' which is emphasized on concepts and inquiry. 2. For the social problem centered integration, we selected the topic, 'Future of Energy' to resolve the science-related social problems and we applied the instruction model of 'Project Learning' which is emphasized on learner's cognitive process to the topic. 3. For the individual interest centered integration, we selected the topic, 'Transformation of Energy' for the integration of science and individual interest and we applied the instruction model of 'Project Learning' centering learner's interest and concern. Based upon the above direction, we developed the integrated science teaching-learning plans as following steps. First, we organized 'Integrated Teaching-Learning Contents' according to the topics. Second, based upon the above organization, we designed 'Instructional procedures' to integrate within the topics. Third, in accordance with the above 'Instructional Procedures', we created 'Instructional Coaching Plan' that can be applied in the practical world of real classrooms. These plans can be used as models for the further development of integrated science instruction for teacher preparation, textbook development, and classroom learning.

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Middle School Home Economics Teachers' Perception and Needs of Self Supervision Related to Home Economics Subject Matter (중학교 가정과교사의 가정교과관련 자기장학에 대한 인식과 자기장학 활성화를 위한 요구)

  • Nam, Yun-Jin;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.20 no.1
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    • pp.45-62
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    • 2008
  • The purpose of this study was to investigate middle school home economics(HE) teachers' perception and needs on self supervision related to HE subject matter, Using the methods of survey and interview, 177 samples were collected. For collected surveys, mean value, standard deviation, frequency, percentage analysis were performed by using an SPSS/Win (ver10.1) program. The results of this study were as follows. First, the middle school HE teachers recognized that self supervision related to HE subject matter was absolutely needed to expand the improvement of techniques for teaching instructions and the width of knowledge on the studies on textbook. Second, the middle school HE teachers recognized the necessary parts of self supervision related to HE subject matter as HE teaching-learning methods, the studies on textbook contents, and HE education philosophy in order. Third, the middle school HE teachers recognized that it would be helpful in improving their HE class and expertise in order of field survey, participation in various training programs, utilization of mass media, participation in societies for researches and meetings and information sharing with co-teachers among the types of self supervision. Fourth, the middle school HE teachers needed the reduction in miscellaneous duties, less pressure for time, restoration of teachers' desire, support of physical resources (improvement of various environments such as classrooms and special rooms), economic support and various support programs (expanding the opportunities to participate in training and society and establishment of a database for relevant materials, etc.) to facilitate self supervision. As such, the middle school HE teachers' overall recognition on HE-related self supervision became significantly higher. To enhance the HE-related expertise, however, it would be necessary to conduct concrete and active support for HE education, philosophical area and the studies on textbook contents as well as the teaching-learning methods for HE in which teachers' demand was high. In addition, the HE teachers wanted to have an easy and quick access to various HE-related data; therefore, it would be urgent to summarize scattered relevant data and support the HE teachers more systematically.

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