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A Geographical Study of Therapeutic Spaces after the Disaster of the MV Sewol in a Local Community (세월호 참사 이후 지역 커뮤니티에 형성된 치유의 공간에 대한 지리적 고찰)

  • Park, Sookyung
    • Journal of the Korean Geographical Society
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    • v.52 no.1
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    • pp.25-53
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    • 2017
  • The ultimate goal of this research is to examine the geographical characteristics of therapeutic spaces where have been appeared in Wa-dong and Gojan-dong, Ansan-si after the disaster of the MV Sewol. As looking into the inside, the aim of the therapeutic spaces, which cover each target group (victims) individually, is various and different because the disaster of the MV Sewol generated various direct and indirect victims requiring healing. The therapeutic spaces are estimated at about 10 organizations and are leaded by private agents predominantly. Furthermore, the therapeutic spaces are located near, but are aside from Danwon high school where many students are reported killed and injured in the incident. And the therapeutic spaces provide simple and repetitive diversions, for example, having a meal, knitting and studying, rather than special programs to restore a broken daily life to the original state. On the basis of such a background, the geographical characteristics of the therapeutic spaces related to the disaster of the MV Sewol can be summarized as follows; first, it seems that target groups accept the therapeutic spaces as the concept of place gradually. Even though most of the therapeutic spaces were suggested by third parties at first, target groups are involved in the management and recollection of their own therapeutic spaces as well as the plan for a future direction now; and consider the therapeutic spaces as exclusive properties. Second, the disaster of the MV Sewol have embedded collective trauma to not only direct victims, but extensive groups such as parents, brothers and sisters, relatives, friends and neighbors as noted earlier. Therefore, the therapeutic spaces support comprehensive target groups; but each therapeutic space is not overlapped each other. However, to solve collective trauma in a local community effectively, the therapeutic spaces are networked closely and build a regular cooperative system. Third, a continuous memory is mentioned as an important point to overcome collective trauma, but some phenomena such as fatigue and conflict with neighbors, out-migrants and a faded atmosphere as time passes act as risk factors in Ansan-si. To keep a continuous memory, the therapeutic spaces attempt the recovery of local communities and devise various events, for example, cultural performances; furthermore, are closely connected with external organizations.

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Hardware Approach to Fuzzy Inference―ASIC and RISC―

  • Watanabe, Hiroyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.975-976
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    • 1993
  • This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

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A Study on the Administration for the Han River Water Quality Control (漢江 水質保全 行政에 관한 硏究)

  • Kim, Kwang Hyop
    • Journal of Environmental Health Sciences
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    • v.10 no.2
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    • pp.9-40
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    • 1984
  • This thesis purports to overview the diverse administrative and organizational factors and plannings developed by the government organizations, municipal or otherwise, to tackle the Han River water pollution issues in the past years. This thesis also looks into the ever-worsening Han River water pollution problems, in particular, in terms of the various government plans ostensibly designed to reduce the pollution level but with little success. Also dealt with are the efficiencies with which the laws and decrees on water pollution the administrative organizations put to use in the prosecution of the diverse antiwater pollution projects involving the Han River basin. From the early 1960's up to the 1970's the government had concentrated on the growth-oriented economic policy with the result that little attention had been paid to the water pollution and other environmental issues that are bound to arise from the massive economic growth. Belatedly, the five-year Hah River Development Project was initiated in 1982 with emphasis on reducing the water pollution level at Hah River to the minimum. The following are the gists of the thesis and recommendations for the future antiwater pollution plans by the administrative organizations: 1. Documents to date indicate that the irrigation projects along the Han River area had been the main focus of attention during the Yi Dynasty and under the Japanese rule of the country. 2. Despite that the water pollution issue became the subject of many debates among the academic and research institutions in the 1960's and in the 1970's, the administrative organizations in charge of the Han River water quality control failed to come up with a concrete plan for the river's water quality control. 3. Nevertheless, the water pollution of the Han River area in fact began in the 1950's, with the unprecedented concentration into Seoul of population and the industrial facilities on a larger scale, in particular, enforced by the government's strong growthoriented policy in its Economic Development plans in the 1960's. 4. Starting in the 1960's, the Han River water pollution level dramatically increased, but the government was reluctant to promulgate or put into effect strong measures to curb the many factors contributing to the river water pollution, thus worsening the environmental issues along the Han River basin. 5. The environmental protection law and other laws and decrees relating to the antiwater and air pollution issues that were subsequently put into effect underwent so many changes that efficient anti-water pollution policies could not be effected for the Han River basin. The frequent organizational reshuffle within the administrative units concerned with environmental problems has resulted in the undue waste in personnel management and finance. 6. The administration on the environmental protection could not be efficiently carried out due to the organizational overlapping. Under the existing law, frequent organizational frictions and inefficiency are bound to occur among the central government offices themselves, as well as between the central government and the Seoul city administration, and among the city's administrative offices over the conservation of the Han River basin and over the river's anti-water pollution issue. 7. In the planning and prosecution of the Han River project, political influences from the president down to the lower-level politicious appear to have been involved. These political influences in the past had certainly had negative influence on the project, nevertheless, it appears that in the recent years, these political influences are not all that negative in view of the fact that they serve as a positive contributing factor in developing a better water quality control project along the Han River basin. The following are a few recommendations based on the data from the thesis: First, officials in charge of the Han River water quality control should pay attention to a careful screening of the opinions and recommendations from the academic circles and from the public should be made so that the government could better grasp the core issues in the environmental problems that require preventive and other necessary measures. Second, vigorous redistribution policies of population and industrial facilities away from the Seoul area should be pursued. Third, the government should refrain from revising or revamping too frequently the laws and decrees on the anti-water pollution, which is feared to cause undue inconveniences in the environmental administration. Fourth, a large-scale streamlining should be made to the existing administrative organization in an effort to do away with the inter- and intra-organizational friction. It is recommended that a secretariat for the Hah River basis conservation be established. Fifth, High-level administrative officials, with a thorough knowledge and vision on the Han River water quality control, should be prepared to better deal with the budgeting and personnel management for the Han River water pollution control not only at the control government, but also at the Seoul city municipal government levels. Environmental issues should be kept distinct from political issues. Environmental issues should not serve as a window-dressing for sheer political purposes. Sixth, the Hah River proiect should also include, along with the main Han River basin, those areas covering North Han River, South Han River, and the tributaries to the main river basin. The 'Han River Basin Water Quality Control Board' should be established immediately as a means of strengthening the current Han River basin water quality control policy. Seventh, in drawing up the Han River proiect, the administrative officials should be aware that Han River basin is a life line for those people in the region, providing them with not only a sheer physical space, but with a psychological living space for their everyday life.

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Social Welfare Policy Expansion and Generational Equity: Generational Accounting Approach (복지지출 확대가 세대 간 형평성에 미치는 효과 분석: 세대 간 회계를 이용한 접근)

  • Chun, Young Jun
    • KDI Journal of Economic Policy
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    • v.34 no.3
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    • pp.31-65
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    • 2012
  • We study the sustainability of the current fiscal policy of Korea, and the effects of the social welfare policy expansion, which has been recently discussed among the political circles, on the government budget and the generational equity, using generational accounting. We follow the generational accounting approach, considering the fact that most of the social welfare policies are the entitlement programs, which imposes the limitation of the policy maker's discretion to control the cost of their provision. The social welfare expenditure will change due to the change in the policy environments of the future, such as population aging. Therefore, we need to take into account the government cash flow of the future as well as of the present to investigate its effects on the fiscal sustainability, which implies that the national debt or the budget balance is not a proper index for the investigation. Our findings are as follows. The current fiscal policies are not sustainable, and the long-term budgetary imbalance is shown very serious. The required tax adjustment, which is defined as the percentage change of tax burden required to attain the long-term budgetary balance, is very large. Unless the level of the government expenditure is properly controlled, the tax burden and the social contribution level will rise to the untolerable level. Moreover, the expansion of the social welfare policies, which has been discussed among the political circles, will substantially increase the fiscal burden of the future generations. Even though the provision of the free lunch to the primary and the secondary school students, the free child care, and the discounted college tuition do not increase the fiscal burden much, because their magnitude at present is not large and will decrease due to the decrease in the number of the newborns and the students resulting from the fall in the fertility rate, that of the free health care service will increase tax burden of the future generations very much, because the magnitude of the government expenditure needed at present is very large and the population aging will further increase the magnitude of the health care expenditure. The findings indicate that the structural reforms, to prevent the explosive increase in the social welfare expenditure in the future, are necessary before the implementation of the welfare policy expansion. In particular, the cost control of the social transfers to the elderly needs to be made, because the speed of the population aging of Korea is among the highest in the world. The findings also indicate that the budget balance or the national debt can cause the fiscal illusion, which makes the Korean government budget look sound, even though the fiscal policy will rapidly increase the social welfare expenditure in the future, as the population ages. The generational accounting, which takes into account the cash flow of the future as well as of the present, unlike the budgetary balance and the national debt, which shows the results of the government financial activities of the past and the present, is a useful method to overcome the fiscal illusion.

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A Study on the Relationship of Children's Development and Book Preference (아동의 심리발달과 도서선호의 변화)

  • Han Yoon Ok
    • Journal of the Korean Society for Library and Information Science
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    • v.17
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    • pp.105-159
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    • 1989
  • The purpose of this study is (a) to identify physical and content elements of children's books that seem to interest second and fifth graders to read, and (b) to observe how the influence of those elements on children's reading interest shifts as children develop. For the purpose of this study, children's books are classified into two groups: 'books of low preference' and 'books of high preference' as determined by second graders, and fifth graders' library circulation record in the library chosen as the sample for the present study. The physical and content elements of the books belonging to these two groups are analyzed and compared. Main findings and conclusions made in this study are summarised as follows: (1) The physical elements of children's books which have significant relationship with second graders' reading preference are illustration quantity, size of types, space between lines, and size of the book. (2) The content elements of children's books which have significant relationship with second graders' reading preference are the readability level of sentences, and the sex of heroes. (3) The physical elements of children's books which have significant relationship with fifth graders' reading preference are illustration quantity, illustration styles, and size of the book. (4) The content elements of children's books which have significant relationship with fifth graders' reading preference are the readability level, the sex of heroes, subject matters, themes and the environmental settings as the background of stories. (5) Reading preference of the pupils at the second and fifth grades are influenced by the quantity of illustration. Second grade pupils prefer reading books which contain a larger quantity of illustrations, whereas 5th grade pupils prefer books which contain less quantity of illustrations. (6) The relationship between second graders' reading preference and the illustration style are rejected at the $10\%$ significance level. A strong relationship, however, appears to exist between 5th graders' reading preference and the illustration style. The 5th grade pupils prefer more realistic illustrations, while cartoons and semi-abstract drawings do not appeal to them. (7) The type size, and space between lines which have had great influence on the book preference of 2nd grade pupils influence little on the 5th grade pupils book preference. (8) Second grade pupils prefer the book of a small Size, whereas 5th grade pupils whose reading taste has developed at a primary stage prefer the book of a large size beyond a certain standard. (9) Second grade pupils prefer reading books which can be easily read, whreeas 5th grade pupils prefer reading books containing difficult sentences. (10) Second grade pupils and the 5th grade pupils both prefer books in accordance with the sex of there heroes. (11) Relationship between second graders' reading preference and the subject matters are rejected at the 10% significance level. A strong relationship, however, appears to exist between 5th graders' reading preference and the subject matter. Fifth grade pupils prefer reading books of which the themes are mystery, exploration and adventure. (12) The theme of books is not proved to relate with the book preference of the 2nd grade pupils, but it is closely related with the book preference of 5th grade pupils. Fifth grade pupils prefer reading books which contain exploratory stories. (13) Second grade pupils are not influenced by the environmental setting of the story, but 5th grade pupils prefer reading stories with the environmental setting in the air. (14) The quantity of illustrations is the element influencing most on .the book preference of the 2nd grade pupils, followed by the space between the lines, which influences least on the book preference of the 5th grade pupils. (15) The physical element influencing most on the book preference of the 2nd grade pupils is the quantity of the illustrations. The physical element which has the most strong influence on the book preference of the 5th graders is illustration styles. (16) The content elements which has much influence on the book preference of the 5th grade pupils are certain kinds of characteristics of heroes. In case of the 2nd grade pupils book preference, striking evidence of such characteristics of heroes is not traced.

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Perception of Visitors on Traditional Marketplaces becoming Tourist Attractions and Supporting Policies - Focused on Tongin Market, Seoul - (전통시장의 관광지화 및 지원정책에 대한 이용객들의 인식 - 서울 통인시장을 중심으로 -)

  • Kim, Yelim
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.6
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    • pp.76-89
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    • 2017
  • Tourism is being used as a tool to regenerate declining spaces. Therefore, the government is carrying out various projects to create tourist attractions to revitalize the traditional marketplace, which is declining nationwide. Because of these government-led projects, traditional marketplaces have been transformed into tourist attractions, and some markets have received enough positive feedback that they have been successfully revitalized economically. However, as marketplaces have become tourist destinations, negative views about government support projects are also increasing. This also leads to conflicts due to differences in perception and interests of stakeholders. This paper examines the process of the marketplace becoming a tourist destination focused on the Tongin Market, in Seoul which has been regenerated as a tourist attraction through a government support project. The purpose of this study is, first, to examine the background of tourist markets becoming tourist attractions and the issues surrounding them. The second was to explore in depth the types of conflict perceptions of visitors, residents and tourists, and the perception of their responses. As a research method, the process of the revitalization of traditional markets through news and existing literature, issues and the difference of perceptions about tourist-centric traditional marketplaces were examined. In addition, the Q methodology was used, which is a qualitative research methodology that can measure the difference of viewpoints and perceptions of specific events in order to analyze the difference of perception among visitors in traditional marketplaces. The results of the study show that there are three main perspectives of difference among visitors' perceptions about government support projects in traditional marketplaces and the marketplace becoming a tourist attraction. The 'policy dependent perspective' emphasizes the necessity of government regulations, a 'critical perspective' criticizes the government's traditional marketplace support policy, and the 'neutral perspective' acknowledges the need for government-led projects and accentuating the internal competitiveness of the marketplace. The study provided the environment for academic discussion about traditional marketplaces, which are becoming tourist attractions nationwide. In addition, this paper can contribute to providing implications for future government projects by analyzing the perception of marketplace visitors.

A Protection Management Characteristic and Preservation Plan of World Heritage Mt. Huangshan (세계유산 황산의 보호관리 특성 및 보전방안)

  • Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.120-128
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    • 2018
  • The purpose of this study is to establish basic data for the continuous protection management policy of domestic natural world heritage and mixed world heritage, and to examine the present situation and characteristics of the protection management according to the World Heritage Convention on the World Heritage listed Huangshan. The results of this study are as follows. First, Huangshan began to be protected by the establishment of the Huangshan Construction Committee in 1933, and after the designation of national park in 1982, laws and regulations were established in the central ministries, And various projects related to utilization have been implemented. Secondly, the establishment of the boundary for protection was actively intervened by the central government, such as the reorganization of the boundary of Huangshan through the administrative district plan. In order to protect the ecological and landscape value as well as the cultural factor, And designated a heritage designated area. Third, the protection management of Huangshan was divided into four major stages. The first phase was divided into the period when administrative measures were taken to manage the protection of Huangshan. The second phase was designated as a national park in Huangshan. The third period was the time of the protection-oriented project according to the recommendation of the international organizations after the World Heritage listed. The fourth period was the expansion of the tourism industry for the continuous use of protection of Huangshan city, My preservation business was being implemented. Fourth, Huangshan is managed by the central government and the city government. Huangshan, which is a mixed heritage, is managed jointly by the Ministry of Cultural Heritage Administration and the Ministry of Natural Heritage Administration. The protection and management of Huangshan promoted the efficiency and expertise of the heritage-related work through the establishment of the administrative unit-specific management system, and the local governments were entrusted with the authority to implement the protection management policies that meet local characteristics. Fifth, the preservation area of Huangshan has been destroyed by the development policy centered on the mountain. In addition, according to the operation of accommodation facilities, there are problems such as sewage, garbage disposal, and environmental pollution caused by tourists, and the damage caused by pests and diseases in planted plantations around the area and changes in ecosystem due to the composition of cable cars. Sixth, for the continuous protection of Huangshan, strict regulations on new construction, extension and management of accommodation are required, and it is necessary to install facilities to limit and control the number of visitors.

Review of the Modern Values of East and West Moat Culture (동·서양 해자(垓字) 문화의 현대적 가치 재조명)

  • Jung, Yong-Jo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.1
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    • pp.25-35
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    • 2017
  • The purpose of this study is to re-exam of the modern values of a moat to utilize it with various functions such as a military defense on the outskirts of the castle, dividing the space by its boundary, controlling the micro-climate in the worsening modern environment with temperature rise due to climate change and habitat reduction of animals, and providing the habitat of animals to modern urban space, etc. The scope of the study is focusing on the castles with the moat installed to prevent the enemy from accessing directly to the wall using a pond or water path for military defense on the outskirts of the castle or to divide it into boundaries. In the Orient, the Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan were selected. In the West, Edinburgh Castle in Britain, Blois Castle in France, Chillon Castle in Switzerland, and Frederiksborg Castle in Denmark were selected for the study. As a research method, literature research and field research were conducted. For the Orient, it was conducted in parallel with the literature research and field research. For the western, it was mainly conducted with literature research. For the literature research, the origin of the moat, the concept of the moat, the function of the moat, the history and culture of the western moat are based on the data from the related institutions and previous studies. For the Orient field research, exploring was conducted in two to three times from Jan. 2016 to Dec. 2016 in each of the target areas of Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan. The contents of the research were analyzed through interviews, photographs, measurements, and observations on the function, size, and characteristics of the moat of each target. The results of this study are as follows. The moat was a structure installed to set a boundary for military defense facilities on the outskirts of a castle and it played an important role as a part of the city in the ancient times of Asia and the West through the Middle Ages. The role of the moat is gradually disappearing due to the disappearance of the purpose of military defense. However, moats are excluded from modern landscape planning, despite the fact that a moat filled with water is a hydrophilic space with great historical and cultural value such as various cultural activities and providing habitats for animals. By reflecting on the moats various functions in modern cities and utilizing it, it is expected to be utilized to bring pleasant air into the city where the circulation of air is blocked and energize the city as a hydroponic element.

PREPARATION OF AMORPHOUS CARBON NITRIDE FILMS AND DLC FILMS BY SHIELDED ARC ION PLATING AND THEIR TRIBOLOGICAL PROPERTIES

  • Takai, Osamu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2000.11a
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    • pp.3-4
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    • 2000
  • Many researchers are interested in the synthesis and characterization of carbon nitride and diamond-like carbon (DLq because they show excellent mechanical properties such as low friction and high wear resistance and excellent electrical properties such as controllable electical resistivity and good field electron emission. We have deposited amorphous carbon nitride (a-C:N) thin films and DLC thin films by shielded arc ion plating (SAIP) and evaluated the structural and tribological properties. The application of appropriate negative bias on substrates is effective to increase the film hardness and wear resistance. This paper reports on the deposition and tribological OLC films in relation to the substrate bias voltage (Vs). films are compared with those of the OLC films. A high purity sintered graphite target was mounted on a cathode as a carbon source. Nitrogen or argon was introduced into a deposition chamber through each mass flow controller. After the initiation of an arc plasma at 60 A and 1 Pa, the target surface was heated and evaporated by the plasma. Carbon atoms and clusters evaporated from the target were ionized partially and reacted with activated nitrogen species, and a carbon nitride film was deposited onto a Si (100) substrate when we used nitrogen as a reactant gas. The surface of the growing film also reacted with activated nitrogen species. Carbon macropartic1es (0.1 -100 maicro-m) evaporated from the target at the same time were not ionized and did not react fully with nitrogen species. These macroparticles interfered with the formation of the carbon nitride film. Therefore we set a shielding plate made of stainless steel between the target and the substrate to trap the macropartic1es. This shielding method is very effective to prepare smooth a-CN films. We, therefore, call this method "shielded arc ion plating (SAIP)". For the deposition of DLC films we used argon instead of nitrogen. Films of about 150 nm in thickness were deposited onto Si substrates. Their structures, chemical compositions and chemical bonding states were analyzed by using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and infrared spectroscopy. Hardness of the films was measured with a nanointender interfaced with an atomic force microscope (AFM). A Berkovich-type diamond tip whose radius was less than 100 nm was used for the measurement. A force-displacement curve of each film was measured at a peak load force of 250 maicro-N. Load, hold and unload times for each indentation were 2.5, 0 and 2.5 s, respectively. Hardness of each film was determined from five force-displacement curves. Wear resistance of the films was analyzed as follows. First, each film surface was scanned with the diamond tip at a constant load force of 20 maicro-N. The tip scanning was repeated 30 times in a 1 urn-square region with 512 lines at a scanning rate of 2 um/ s. After this tip-scanning, the film surface was observed in the AFM mode at a constant force of 5 maicro-N with the same Berkovich-type tip. The hardness of a-CN films was less dependent on Vs. The hardness of the film deposited at Vs=O V in a nitrogen plasma was about 10 GPa and almost similar to that of Si. It slightly increased to 12 - 15 GPa when a bias voltage of -100 - -500 V was applied to the substrate with showing its maximum at Vs=-300 V. The film deposited at Vs=O V was least wear resistant which was consistent with its lowest hardness. The biased films became more wear resistant. Particularly the film deposited at Vs=-300 V showed remarkable wear resistance. Its wear depth was too shallow to be measured with AFM. On the other hand, the DLC film, deposited at Vs=-l00 V in an argon plasma, whose hardness was 35 GPa was obviously worn under the same wear test conditions. The a-C:N films show higher wear resistance than DLC films and are useful for wear resistant coatings on various mechanical and electronic parts.nic parts.

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The Making of Local Socio-economic Space and the Role of Local Government, In Case of Taegu and textile industry (지역사회.경제 공간의 형성과 지방정부의 역할, 대구시와 섬유산업의 경우)

  • Park, Kyu-Taeg
    • Journal of the Korean association of regional geographers
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    • v.7 no.3
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    • pp.91-106
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    • 2001
  • Local government takes an active role in the (re)making of local socio-economic space. To support such an argument, the three different actions by the local government of Taegu, urban planning and local industrial districts, the establishment of special educational institutions, and textile festival are analyzed. The division of the city's space into residential, commercial, and industrial area by local government constrained the location of local manufacturing industries. It also forced textile industry to move to the outskirts of Taegu. As the education level in South Korea rose after the late 1970s, the local government of Taegu as well as local industrial capitalists had to do something to acquire a stable supply of labor to local manufacturing industries, particularly textile one. After the late 1970s, the special classes for the education of local workers, especially textile ones were established within vocational high school and company-operated high schools were also built in Taegu. Finally, local government started a program of textile festival in 1985. Through textile festival, local government as well as local textile business people tried to reproduce textile industry as the main economic activity of Taegu.

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