• Title/Summary/Keyword: space form

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Geographic Conditions and Garden Designs of Byeol-seo Scenic Site of Gimcheon Bangcho-Pavilion and Mrs Choi's Pond (별서 명승 김천 방초정(芳草亭)과 최씨담(崔氏潭)의 입지 및 조영 특성)

  • Rho, Jae-Hyun;Lee, Hyun-Woo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.1
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    • pp.71-82
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    • 2016
  • Through literature review and on-site survey of Gimcheon Bangcho pavilion(芳草亭), the features of garden design(庭園意匠) including geographic conditions, landscape modeling of Nujeong(樓亭) and Jidang(池塘, Pond), and scenic interpretations in Nujeong Jeiyoung poetry(樓亭題詠詩) have been carefully researched and the findings are presented below. Bangcho pavilion is located in a village called Wonteomaeul, which belongs to the feng shui state of golden hairpin and floating lotus. It has long been the cultural hub of communication and social interactions among the villagers. The Head House of Jeongyanggong(靖襄公宗宅), the main house(本第) of the Yeonan Yi Clan(延安李氏), is about 150m away from Bangcho pavilion, an artistic space whose landscape modeling is of the form called Nujeong. The name 'Bangcho' reflects the noble man(君子)'s determination: "I yearn for the place where honey parrots fly and the fragrant grass grow." From the two story structure of the pavilion where there is an additional floor installed to the central ondol room by a four-sided subdivision door, one can detect the aspiration of the men for pursuing an open view. One can also observe the efforts in designing the room to be used for multiple purposes from a private place to an office for periodic publication of a family lineage document called "Garyejunghae(家禮增解)". Bangcho pavilion's main sight of interest is Mrs Choi's Pond(崔氏潭), the one and only garden structure that comprises the twin round island of square pond(方池雙圓島) among the existing Jidangs in Korea. In this special Jidang, there are two coexisting islands that represent a well thought out garden facility for symbolizing conjugal affection and unyielding fidelity between master and servent(主從). In addition, the three inflows and one outflow facing the Ramcheon valley is regarded as an ideal garden design optimized for performing the function of a village bangjuk which is the site for undercurrent creation and ecological reprocessing. At present, Giant pussy willow is the only circular vegetation identified in the area of Bangcho pavilion, although this plant species is about to wither away judging from the signs of decrepitude that seems to persist for two out of three weeks. The old pine tree that appears in the 1872 Jeiyoung poetry of Byeongseon Song(宋秉璿) no longer exists. Anjae(安齋) Jang Yoo(張瑠)'s "Eight Scenary on Bangcho pavilion(芳草亭八詠)" and its expansive reproduction "Ten Scenary on Bangcho pavilion(芳草亭十景)" from Gwagang(守岡) Lee Manyoung(李晩永) depict vividly the pastoric scenery of an idyll(田園景) that stretches throughout the natural and cultural landscape of the province of Gimcheon and Guseong surrounding the Bangcho pavilion. The Bangcho pavilion sutra aims to establish Bangcho pavilion and the village of Wonteomaeul as the centre of microcosmos by dividing and allocating its scenic features according to the four seasons and times(四季四時), the eight courses(八方) and the meteorological phenomena, and it is the incarnation(顯現) of landscape perception upon the Byeol-seo Scenic site of Bangcho pavilion, the cultural hub of the region.

Interpretation of Landscape Elements in Borimsa Temple after 17th Century (17세기 이후 장흥 보림사(長興 寶林寺)의 경관요소 해석)

  • Kim, Kyu-Won;Sim, Woo-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.1
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    • pp.110-118
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    • 2015
  • Borimsa Temple in Jangheung, one of the Goosanseonmoon of Shilla Dynasty, calls for a study in the field of landscape architecture because it has very significant elements in cultural and ecological landscaping aspects. This study examined the changes in landscaping elements of Borimsa Temple since the 17th century in order to newly recognize cultural landscaping value of space composition elements for traditional temple and to verify landscape architectural position. For research method, literatures such as Sajeonggi (事蹟記), Joongchanggi, a surveyed map by Fujishima Gaijiro in 1928 and Joseon Gojeogdobo (朝鮮古蹟圖譜) and modern documents including Borimsa Temple Precision Ground Survey Report and photographic records of National Archives of Korea and provincial governments were examined together with a field survey in order to trace changes in landscape elements such as buildings within the temple site, pond and temple forest. The results are as the following: First, for geographical locations of Borimsa Temple, it is located in an auspicious location and Shipyuknahansang and Cheonbul were placed in a supplementary purpose according to the contents of Bojoseonsatapbi. Compared to Namhwaseonsa Temple in China, it has a similar environmental composition but the fact that buildings were placed on platforms is a distinctive difference. Second, architectural landscape of Borimsa Temple went through the Japanese colonial era and Korean War and still going through changes today. Thus, there shall be some appropriate measures such as to establish an archive of past landscape data. Third, the contents of Borimsa Temple Sajeonggi suggests that the pond of Borimsa Temple had been in a indeterminate form with stones on the outer edge. Its name could have been Yongcheon (湧泉) according to the contents of Joongchanggi. Also, the current landscape, in comparison with past photographs, is a result of changes from surface raise occurred by ground reinforcement within the temple site. Fourth, Jangsaengpyoju (長生標柱) mentioned in Bojoseonsatapbi and Borimsa Temple Sajeonggi was thought to be the dried juniper tree in front of Daewoongbojeon, which can be found in past photographic documents but, it is now assumed to be Seokbihyeong (石碑形) considering the Gukjangsaeng and Hwangjangsaeng of Dogapsa Temple of the similar time period. Moreover, Hongsalmoon mentioned in Joongchanggi was established by King's order after the Manchu war of 1636 in praising of Buddhist monks those who had volunteered to fight for the country. Fifth, it is apparent in Borimsa Temple Joongchanggi that geomancy was a consideration in landscaping process of Borimsa Temple, and the record indicates that pine trees, bo trees and persimmon trees were planted. Sixth, tea tree forest was verified of its historical root that is Seongchailyeo from Unified Shilla through passing down of Jeong Yak-yong's Goojeunggoopo method and relevant documents of Seon Master Choui and Yi Yu-won. Seventh, nutmeg tree forest suggests that nutmegs were used in national ceremonies and for medical uses. The nutmeg tree forest was also verified of its role as Naehwasoorimdae (a forest built to prevent fire from spreading) through aerial photographs and placement of a forest reserve.

Development of Agent-based Platform for Coordinated Scheduling in Global Supply Chain (글로벌 공급사슬에서 경쟁협력 스케줄링을 위한 에이전트 기반 플랫폼 구축)

  • Lee, Jung-Seung;Choi, Seong-Woo
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.213-226
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    • 2011
  • In global supply chain, the scheduling problems of large products such as ships, airplanes, space shuttles, assembled constructions, and/or automobiles are complicated by nature. New scheduling systems are often developed in order to reduce inherent computational complexity. As a result, a problem can be decomposed into small sub-problems, problems that contain independently small scheduling systems integrating into the initial problem. As one of the authors experienced, DAS (Daewoo Shipbuilding Scheduling System) has adopted a two-layered hierarchical architecture. In the hierarchical architecture, individual scheduling systems composed of a high-level dock scheduler, DAS-ERECT and low-level assembly plant schedulers, DAS-PBS, DAS-3DS, DAS-NPS, and DAS-A7 try to search the best schedules under their own constraints. Moreover, the steep growth of communication technology and logistics enables it to introduce distributed multi-nation production plants by which different parts are produced by designated plants. Therefore vertical and lateral coordination among decomposed scheduling systems is necessary. No standard coordination mechanism of multiple scheduling systems exists, even though there are various scheduling systems existing in the area of scheduling research. Previous research regarding the coordination mechanism has mainly focused on external conversation without capacity model. Prior research has heavily focuses on agent-based coordination in the area of agent research. Yet, no scheduling domain has been developed. Previous research regarding the agent-based scheduling has paid its ample attention to internal coordination of scheduling process, a process that has not been efficient. In this study, we suggest a general framework for agent-based coordination of multiple scheduling systems in global supply chain. The purpose of this study was to design a standard coordination mechanism. To do so, we first define an individual scheduling agent responsible for their own plants and a meta-level coordination agent involved with each individual scheduling agent. We then suggest variables and values describing the individual scheduling agent and meta-level coordination agent. These variables and values are represented by Backus-Naur Form. Second, we suggest scheduling agent communication protocols for each scheduling agent topology classified into the system architectures, existence or nonexistence of coordinator, and directions of coordination. If there was a coordinating agent, an individual scheduling agent could communicate with another individual agent indirectly through the coordinator. On the other hand, if there was not any coordinating agent existing, an individual scheduling agent should communicate with another individual agent directly. To apply agent communication language specifically to the scheduling coordination domain, we had to additionally define an inner language, a language that suitably expresses scheduling coordination. A scheduling agent communication language is devised for the communication among agents independent of domain. We adopt three message layers which are ACL layer, scheduling coordination layer, and industry-specific layer. The ACL layer is a domain independent outer language layer. The scheduling coordination layer has terms necessary for scheduling coordination. The industry-specific layer expresses the industry specification. Third, in order to improve the efficiency of communication among scheduling agents and avoid possible infinite loops, we suggest a look-ahead load balancing model which supports to monitor participating agents and to analyze the status of the agents. To build the look-ahead load balancing model, the status of participating agents should be monitored. Most of all, the amount of sharing information should be considered. If complete information is collected, updating and maintenance cost of sharing information will be increasing although the frequency of communication will be decreasing. Therefore the level of detail and updating period of sharing information should be decided contingently. By means of this standard coordination mechanism, we can easily model coordination processes of multiple scheduling systems into supply chain. Finally, we apply this mechanism to shipbuilding domain and develop a prototype system which consists of a dock-scheduling agent, four assembly- plant-scheduling agents, and a meta-level coordination agent. A series of experiments using the real world data are used to empirically examine this mechanism. The results of this study show that the effect of agent-based platform on coordinated scheduling is evident in terms of the number of tardy jobs, tardiness, and makespan.

A Real-Time Stock Market Prediction Using Knowledge Accumulation (지식 누적을 이용한 실시간 주식시장 예측)

  • Kim, Jin-Hwa;Hong, Kwang-Hun;Min, Jin-Young
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.109-130
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    • 2011
  • One of the major problems in the area of data mining is the size of the data, as most data set has huge volume these days. Streams of data are normally accumulated into data storages or databases. Transactions in internet, mobile devices and ubiquitous environment produce streams of data continuously. Some data set are just buried un-used inside huge data storage due to its huge size. Some data set is quickly lost as soon as it is created as it is not saved due to many reasons. How to use this large size data and to use data on stream efficiently are challenging questions in the study of data mining. Stream data is a data set that is accumulated to the data storage from a data source continuously. The size of this data set, in many cases, becomes increasingly large over time. To mine information from this massive data, it takes too many resources such as storage, money and time. These unique characteristics of the stream data make it difficult and expensive to store all the stream data sets accumulated over time. Otherwise, if one uses only recent or partial of data to mine information or pattern, there can be losses of valuable information, which can be useful. To avoid these problems, this study suggests a method efficiently accumulates information or patterns in the form of rule set over time. A rule set is mined from a data set in stream and this rule set is accumulated into a master rule set storage, which is also a model for real-time decision making. One of the main advantages of this method is that it takes much smaller storage space compared to the traditional method, which saves the whole data set. Another advantage of using this method is that the accumulated rule set is used as a prediction model. Prompt response to the request from users is possible anytime as the rule set is ready anytime to be used to make decisions. This makes real-time decision making possible, which is the greatest advantage of this method. Based on theories of ensemble approaches, combination of many different models can produce better prediction model in performance. The consolidated rule set actually covers all the data set while the traditional sampling approach only covers part of the whole data set. This study uses a stock market data that has a heterogeneous data set as the characteristic of data varies over time. The indexes in stock market data can fluctuate in different situations whenever there is an event influencing the stock market index. Therefore the variance of the values in each variable is large compared to that of the homogeneous data set. Prediction with heterogeneous data set is naturally much more difficult, compared to that of homogeneous data set as it is more difficult to predict in unpredictable situation. This study tests two general mining approaches and compare prediction performances of these two suggested methods with the method we suggest in this study. The first approach is inducing a rule set from the recent data set to predict new data set. The seocnd one is inducing a rule set from all the data which have been accumulated from the beginning every time one has to predict new data set. We found neither of these two is as good as the method of accumulated rule set in its performance. Furthermore, the study shows experiments with different prediction models. The first approach is building a prediction model only with more important rule sets and the second approach is the method using all the rule sets by assigning weights on the rules based on their performance. The second approach shows better performance compared to the first one. The experiments also show that the suggested method in this study can be an efficient approach for mining information and pattern with stream data. This method has a limitation of bounding its application to stock market data. More dynamic real-time steam data set is desirable for the application of this method. There is also another problem in this study. When the number of rules is increasing over time, it has to manage special rules such as redundant rules or conflicting rules efficiently.

Network Planning on the Open Spaces in Geumho-dong, Seoul (서울 금호동 오픈스페이스 네트워크 계획)

  • Kang, Yon-Ju;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.5
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    • pp.51-62
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    • 2012
  • Geumho-dong, Seoul, a redeveloped residential area, is located in the foothills of Mt. Eungbong. The geographical undulation, the composition of a large apartment complex, and the partial implementation of the redevelopment project have caused the severe physical and social disconnections in this area. In order to recover functioning in the disconnected community, this study pays attention to the regeneration of the open spaces as an everyday place and in the form a network system among those open spaces. Various types of the open spaces are classified into points or faces, 'bases' and linear 'paths' analyze the network status. More than half of the open space have connecting-distance of 500m or more. Furthermore, many areas are not even included in the service-area of the open spaces. Analysis of the connectivity and integration value using the axial map has carried out to check weak linkages and to choose the sections where additional bases are required. In addition, to improve the quality of the bases and the paths, a field investigation is conducted and problems are diagnosed. The network planning of the open spaces in Geumho-dong is established, ensuring the quality and quantity of bases and paths. The plan includes the construction of an additional major base in the central area and six secondary bases in other parts, and comes up with ways to improve the environment of underdeveloped secondary bases. In the neighborhood parks at Mt. Daehyun areas, the major path are added, and the environment of the paths is improved in certain areas. Because of the network planning, the connecting-distances between bases are reduced significantly, the connectivity and integration value of the area are increased, and the service areas of the open spaces cover the whole area properly. Although this study has some limitations such as the needs for the legal and institutional supports and difficulties of a quantitative indexing process, its significance lies in the suggestion of a more reasonable and practical plan for the overall network system by defining complex types of open spaces simply and clearly and by examining the organic relationships quantitatively and qualitatively.

Social Learning Values in the Justification Discourses for One Million-pyeong Park, Busan, South Korea (담론분석을 통한 100만평공원운동의 사회학습적 가치)

  • Lee, Sungkyung;Kim, Seung-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.5
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    • pp.19-27
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    • 2013
  • This paper claims that the One Million-peyong Park(hereafter abbreviated as OMP) project is different from a typical citizen participatory park project by recognizing the exceptional leadership of the Civic Committee for the One Million-pyeong Park Construction(CCOMPC) in promoting and developing the OMP project. Since 2001 the CCOMPC has published a variety of written promotional materials to inform and educate the public about the project. In terms of approaching the promotional materials, this research focuses on the use of language on how the CCOMPC justifies the OMP project, namely the OMP justification discourse, and considers the discourse as a unique form of social document that represents the perspective of the CCOMPC in explaining the local environmental issues and values of urban parks to the public. Using a discourse analysis method, this research analyzes the justification discourses and investigates how they changed over the three main development phases of the OMP: the initiation and preliminary development phase(1999-2001.2), the development phase (2001.2-2008), and the time period after the greenbelt policy release on Dunchi Island(2008-present). In each discourse, the OMP project is rationalized as a citizen participation park project that (1) aims to enhance the quality of public green space in Busan, (2) is accompanied by various community engagement programs that emphasize the value of urban nature and environmental education to expand citizen participation, and (3) has contributed to the National Urban Park Bill. This research emphasizes the role of the discourses in helping the public gain a critical understanding about the local environment and values of urban parks. By analyzing the contents of the discourses, it explains the social learning values of the OMP expressed in the discourses.

Heterogeneous Oxidation of Liquid-phase TCE over $CoO_x/TiO_2$ Catalysts (액상 TCE 제거반응을 위한 $CoO_x/TiO_2$ 촉매)

  • Kim, Moon-Hyeon;Choo, Kwang-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.3
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    • pp.253-261
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    • 2005
  • Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

A Study on Needs of 'Strolling (Yu)' at the Fine Arts Education - Focused on Oriental Painting - (미술교육에 있어서 '노닐음(遊)'에 대한 필요성 연구 - 동양화를 중심으로 -)

  • Jeong, Gyeong-Cheol
    • Journal of Science of Art and Design
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    • v.12
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    • pp.97-124
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    • 2007
  • The paper examined whether the fine arts education needed concept of 'Yu' that was suggested by, 'Soyoyu' of Jangja, a representative philosopher of Doka. At first, the paper defined concept of 'Yu' of Jangja as well as background and needs of the fine arts education, and investigated values of 'Yu' of the Oriental painting in aesthetic way to examine whether today's Yu concept can be applied to modern Oriental fine arts education to express. Chapter 2 examined concept and thought of 'strolling (Yu)', and Chapter 3 did background and needs of the fine arts education. Chapter 4 examined an access to practical technique education of the Oriental painting through 'strolling (Yu)': At first, the chapter investigated 'Heosil' of space concept that was researched at Chapter 2, 'Pilmuk' of expression technique, and 'Saeui' of state of spiritual canvas of painters. The findings were as follow: Firstly, when relation between Yu and Oriental paintings was investigated based on formative idea, 'Heo' reminded appreciators of association of ideas, hint and imagination, etc by, 'Sil' that other objects disclosed intrinsic attributes so that it indicated border of positive forgetfulness expressed by artists to have same border between 'Heo' and 'Yu'. Therefore, both 'Heo' and 'Sil' could build up expression as well as appreciation ability by experiencing formative idea to develop creativity and to build emotion and to cognize needs of the fine arts education. Secondly, the artistic state of 'Shin', 'Ki (Simjae)', 'Jeonshin' and, Saeui', etc could be expressed with strength and weakness of both Yin and Yang of Pilmuk. Therefore, the Pilmuk were linked even with creation of both Hyeongsa and artistic form of Saeui. Therefore, freedom at border of spiritual 'strolling' could produce creative power being expressed by thinking, natural appreciation ability, and education that could judge values of aesthetic culture. Therefore, cultivation of aesthetic eye, development of creativity, build up of formative ability and education of human nature, etc could keep identity of the Oriental fine arts education at various modern fine arts.

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The Relationship with Electronic Trust, Web Site Commitment and Service Transaction Intention in Public Shipping B2B e-marketplace (해운 B2B e-marketplace의 전자적 신뢰, 사이트몰입 및 서비스 거래의도와의 관계성)

  • Kim, Yong-Man;Kim, Seog-Yong;Lee, Jong-Hwan;Shim, Gyu-Yeol
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.4
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    • pp.113-139
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    • 2007
  • This study aims to, looking from a standpoint of network, has investigated the shipping industry's B2B e-marketplace, the characteristics that can earn electronic trust from the users, and characteristics of the web-site. It has examined the mechanism whereby electronic trust be earned and how it affects web-site involvement and service transaction intention. Ultimately, The study attempts to make proposals whereby such trust can lead for a cooperative trading community in the shipping industry's B2B e-marketplace The Covalence structural equation modeling was designed and empirically tested for the shipping industry's B2B e-marketplace. The shipping industry employees were given questionnaires and data were analyzed. Except for perceived security of the three characteristic factors on the web-site, the perceived site quality and characteristics factors in operation only affected co-variables. Transaction Fairness was determined to be the most important factor among exogenous factors increasing electronic trust. With regards to transaction rules, if a transaction is beneficial only to one side, then no long term transaction will not take place. If the concerned parties properly recognize that transaction fairness is crucial to electronic transaction, then it will enormously contribute to successful operations of shipping e-marketplace. Also, Perceived efficiency in transaction also affects electronic trust. This reduces transaction costs and speeds up and simplifies the transaction process. It has reduced greater time and costs than existing off-line transaction, and would positively affect electronic trust. By making an open forum for participants to obtain information for transaction, they can gather useful information, and at the same time, the web-site operator can provide information, which, in turn, will increase electronic trust in electronic transaction. Furthermore, such formation of trust in electronic transaction influences shipping companies in such a way that they will want to continuously participate in the transaction, raising web-site involvement. The result of increased trust is that shipping companies in the future will do business with each other and form a foundation for continuous transactions amongst themselves. Consequently, the formation of trust in electronic transaction greatly influences web-site involvement and service transaction intention. The results of the study have again proved that in order to maintain continuous business relationship with the current clients, electronic trust in virtual space, which operates the shipping industry's B2B e-marketplace, is important for the interested parties.

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Application of CMP Process to Improving Thickness-Uniformity of Sputtering-deposited CdTe Thin Film for Improvement of Optical Properties (스퍼터링 증확 CdTe 박막의 두께 불균일 현상 개선을 위한 화학적기계적연마 공정 적용 및 광특성 향상)

  • Park, Ju-Sun;Lim, Chae-Hyun;Ryu, Seung-Han;Myung, Kuk-Do;Kim, Nam-Hoon;Lee, Woo-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.375-375
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    • 2010
  • CdTe as an absorber material is widely used in thin film solar cells with the heterostructure due to its almost ideal band gap energy of 1.45 eV, high photovoltaic conversion efficiency, low cost and stable performance. The deposition methods and preparation conditions for the fabrication of CdTe are very important for the achievement of high solar cell conversion efficiency. There are some rearranged reports about the deposition methods available for the preparation of CdTe thin films such as close spaced sublimation (CSS), physical vapor deposition (PVD), vacuum evaporation, vapor transport deposition (VTD), closed space vapor transport, electrodeposition, screen printing, spray pyrolysis, metalorganic chemical vapor deposition (MOCVD), and RF sputtering. The RF sputtering method for the preparation of CdTe thin films has important advantages in that the thin films can be prepared at low growth temperatures with large-area deposition suitable for mass-production. The authors reported that the optical and electrical properties of CdTe thin film were closely connected by the thickness-uniformity of the film in the previous study [1], which means that the better optical absorbance and the higher carrier concentration could be obtained in the better condition of thickness-uniformity for CdTe thin film. The thickness-uniformity could be controlled and improved by the some process parameters such as vacuum level and RF power in the sputtering process of CdTe thin films. However, there is a limitation to improve the thickness-uniformity only in the preparation process [1]. So it is necessary to introduce the external or additional method for improving the thickness-uniformity of CdTe thin film because the cell size of thin film solar cell will be enlarged. Therefore, the authors firstly applied the chemical mechanical polishing (CMP) process to improving the thickness-uniformity of CdTe thin films with a G&P POLI-450 CMP polisher [2]. CMP process is the most important process in semiconductor manufacturing processes in order to planarize the surface of the wafer even over 300 mm and to form the copper interconnects with damascene process. Some important CMP characteristics for CdTe were obtained including removal rate (RR), WIWNU%, RMS roughness, and peak-to-valley roughness [2]. With these important results, the CMP process for CdTe thin films was performed to improve the thickness-uniformity of the sputtering-deposited CdTe thin film which had the worst two thickness-uniformities of them. Some optical properties including optical transmittance and absorbance of the CdTe thin films were measured by using a UV-Visible spectrophotometer (Varian Techtron, Cary500scan) in the range of 400 - 800 nm. After CMP process, the thickness-uniformities became better than that of the best condition in the previous sputtering process of CdTe thin films. Consequently, the optical properties were directly affected by the thickness-uniformity of CdTe thin film. The absorbance of CdTe thin films was improved although the thickness of CdTe thin film was not changed.

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