• Title/Summary/Keyword: local field

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A study on conduction current and D.C. breakdown characteristics in dielectric liquids (절연유의 도전전류와 직류절연파괴특성에 관한 연구)

  • 서국철
    • 전기의세계
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    • v.30 no.4
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    • pp.231-236
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    • 1981
  • It has been known that D.C. breakdown Voltage is lower than A.C. breakdown Voltage in insulatingoil, but there are still many unvivid points at electric conduction in breakdown or under of high electric field. This study measured the electric current-electric field characteristics (I-E characteristics) and the breakdown Voltage under of D.C. electric field of insulating oil using the system of electrodes that are near the Uniform electric field with a result. I can study, electric conduction in area of high electric field depends upon the Schottky effect. The liquidity of breakdown electric field takes place by the local concentration of electric field. The longer gap is and the more electric current is the more breakdown Voltage decreased. There are not almost the change of electric current-electric field characteristics by materials of electrode.

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A Study of Appropriate Devolution of Environmental Administrative Functions in Korea - Focused on the Transition of Environmental Official's Perception between 2001 and 2003 years - (한국 환경행정기능의 정부간 적정배분에 관한 연구 - $2001{\cdot}2003$년 환경행정공무원의 인식에 대한 비교를 중심으로 -)

  • Chung Yong-Taik;Lee Sung-Bock;Kim Jong-O;Son Bu-Soon
    • Journal of environmental and Sanitary engineering
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    • v.20 no.4 s.58
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    • pp.31-37
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    • 2005
  • The objective of this study is to analyze and suggest the policy on devolution of environmental administrative function between central and local government in Korea. This study also research to make the prospect of power from central government to local government's officers by analyzing the characteristics and contents, standards of local devolution and the attitudes of central and local governments on its process from September 2001 to April 2003. The date collected from the more than 675 questionnairs of government officers included as the Ministry of Environment and local government. The date also collected from interview and field survey. The questionnaire had collected in two times between 2001 and 2003. The environmental administrative function has reallocated from central government to local government since 2001. The devolution focused on simple implemental services and institutional delegated services might result in the lack of initiative and locality of local governments. Therefore, devolution should be proceed towards reinforcing the decision-making capacity and financial and manpower of local government. This paper also showed the weakness on speciality and experience on local bureaucratic in Korean society. This study announced that local government's officer has appeared the negative impact on environmental regulation and the conflict between central and local government.

A Case Study on Storytelling Application of Native Local Foods (향토음식의 스토리텔링 적용 사례연구)

  • Choe, Jeong-Sook;Park, Han-Sik
    • Journal of the Korean Society of Food Culture
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    • v.24 no.2
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    • pp.137-145
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    • 2009
  • The purpose of this study is to present the scheme that can enhance the value of native local foods by analyzing the case into which storytelling is incorporated in order to revitalize native local foods. Towards this end, the cases of native local foods throughout the country were recommended through professional survey and one region among them was finally selected through the field study. The survey on the native local foods was conducted through qualitative study. The four stages of storytelling: the findings of storytelling, the production of storytelling, the experience of storytelling, and sharing of storytelling were analyzed by stage and the contents of the survey by stage were developed. In the findings of story, the origins and background of the main family's foods and food-related stories were derived. The production of stories deals with how to convey the stories of surveyed native local foods to consumers and it presented the stories about the place and food menu. In the experience of storytelling, the physical environment and non-physical environment, in which people visit native local eating houses and experience native local foods were analyzed. Finally, in the sharing of story, how the tourists who have experienced the native local foods make stories and disseminate and share them was analyzed. The significance of this study is that through the storytelling technique it presented the findings, production, experience and sharing of native local foods in the level that can apply to practical business. Although the research is in the stage of inquiry, this study is meaningful in that it presented the basic methodology that can induce the revitalization of the native local food industry through examining the tradition and significance of native local foods that can be found in all the regions of the country.

Collective Forest Management System in Japan: a Case Study in Osawa Property Ward Forest

  • De Zoysa, Mangala Premakumara;Inoue, Makoto;Yamashita, Utako;Hironori, Okuda
    • Journal of Forest and Environmental Science
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    • v.29 no.1
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    • pp.58-70
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    • 2013
  • Iriai an Indigenous forest management system in Japan from the viewpoint of "common pool resources" was a success resilient institution and resulted with sustainable production system and environmental conservation. This study was conducted in Osawa of the Nagano prefecture through group discussions, field observations and an in-depth field survey. Osawa Property Ward Forest is managed under the concept very much similarly to traditional "Iriai". This study firstly examined the changes of collective forest management system in terms of awareness and interest in forest management; forest management activities; role of forest; and collection of forest products. Then it analyzed the current threats for collective forest management have been identified as: land abandonment due to loss of benefits and lack of active community participation; deterioration of forest environment particularly the micro-climate and aesthetic values; conflict with local government authorities restraining the use of money in property ward forest and conflict with outsiders on damping of the garbage. Community cantered forestry management rules; livelihood contribution; protection of environment; local initiatives for protection and economic activities are the prevailing opportunities for collective forest management. The main requirements for revitalization of collective forest management are explained as local reciprocity; imposition of community based forest rules; encouraging local innovations; and building partnerships with stakeholders. Collective forest management system addresses the limitations of conventional forestry models, which had invalidated traditional 'iriai' institutions, and key to restoring sustainable use of forest and environmental resources. Cross-institutional collaborations together with responsibilities of local communities would ensure the revitalization of forest resources.

Study of Materials and Stress Ratios on Fatigue Crack Propagation Rate Using Parameter ΔA (.DELTA.A를 파라미터로 이용한 피로크랙전파속도에 미치는 재료 및 응력비의 영향에 대한 연구)

  • 박영철;오세욱;김광영;허정원;강정호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.7
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    • pp.1373-1380
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    • 1992
  • The local cyclic strain distribution near the crack tip has been investigated by the fine Dot Grid Strain Measurement Method, which had been suggested strain measurement method to resolve experimental difficulties by authors. It has been found that the magnitude of the local cyclic strain distribution(.DELTA..epsilon.$_{eq}$ )near a crack tip has been varied by the applied cyclic load level and material, but the shape of the local cyclic strain distribution near the crack tip has been experimentally scrarcely altered : that is .DELTA..epsilon.$_{eq}$ = .DELTA.A.f(.theta.). $r^{-1}$ . Consequently, the local cyclic strain field near the crack tip could be favorably characterized by a single parameter fatigue strain intensity factor .DELTA.A. In addition, with the viewpoint that .DELTA.A depends on material and load level, .DELTA.A has been applied to evaluate the fatigue crack propagation rate and usefulness of the result has been considered. As a result, it has been ascertained that .DELTA.A has been a useful parameter to evaluate the fatigue crack propagation rate.

Adaptive De-interlacing Algorithm using Method Selection based on Degree of Local Complexity (지역 복잡도 기반 방법 선택을 이용한 적응적 디인터레이싱 알고리듬)

  • Hong, Sung-Min;Park, Sang-Jun;Jeong, Je-Chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.4C
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    • pp.217-225
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    • 2011
  • In this paper, we propose an adaptive de-interlacing algorithm that is based on the degree of local complexity. The conventional intra field de-interlacing algorithms show the different performance according to the ways which find the edge direction. Furthermore, FDD (Fine Directional De-interlacing) algorithm has the better performance than other algorithms but the computational complexity of FDD algorithm is too high. In order to alleviate these problems, the proposed algorithm selects the most efficient de-interacing algorithm among LA (Line Average), MELA (Modified Edge-based Line Average), and LCID (Low-Complexity Interpolation Method for De-interlacing) algorithms which have low complexity and good performance. The proposed algorithm is trained by the DoLC (Degree of Local Complexity) for selection of the algorithms mentioned above. Simulation results show that the proposed algorithm not only has the low complexity but also performs better objective and subjective image quality performances compared with the conventional intra-field methods.

Profile Analysis on Signal Measured Local Ice Load during Icebreaking in Arctic Sea (북극해에서의 쇄빙시 국부 빙하중 계측 신호에 대한 파형 분석)

  • Jeon, Young-Ju;Rim, Chae-Whan;Lee, Tak-Kee
    • Journal of Navigation and Port Research
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    • v.37 no.2
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    • pp.143-148
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    • 2013
  • The aim of this study is to investigate the characteristics on the profile of local ice load acting on side shell of port side in bow part due to broken ice during icebreaking of ships in ice covered waters. The first Korean icebreaking research vessel 'ARAON' had a sea ice field trial in the Arctic Sea during early August, 2010, and the signals due to local ice impact measured from several strain gauges installed at bow part were gathered. It is known that these data with structural response characteristics due to local ice impact have some different characteristics with a typical hydraulic impact pressure - time history. In this study, the time history on the measured signals was analyzed and the characteristic values were presented using non-dimensional parameters.

Mid-IR Luminosity Functions of Local Galaxies in the North Ecliptic Pole Field

  • Kim, Seong Jin;Lee, Hyung Mok;Jeong, Woong-Seob
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.72.3-72.3
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    • 2015
  • We present the mid-infrared (MIR) luminosity function (LF) of local (z < 0.3) star forming (SF) galaxies based on the AKARI's NEP-Wide Survey data. We utilized a combination of the NEP-Wide point source catalogue containing a large number (114,000) of infrared (IR) sources distributed over the wide (5.4 sq. deg) field and spectroscopic redshift (z) data for 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI's continuous $2{\sim}24{\mu}m$ wavelength coverage and the spectroscopic redshifts for sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the mid-infrared. We carried out SED-fit analysis and employed 1/Vmax method to derive the mid-IR (e.g., $8{\mu}m$, $12{\mu}m$, and $15{\mu}m$ rest-frame) luminosity functions. Our results for local galaxies from the NEP region generally consistent with various previous works for other fields over wide luminosity ranges. The comparison with the results of the NEP-Deep data implies the luminosity evolution from higher redshifts towards the present epoch. We attempted to fit our derived LFs to the double power-laws and present the resulting power indices. We also examined the correlation between mid-IR luminosity and total IR luminosity.

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Local Minimum Free Motion Planning for Mobile Robots within Dynamic Environmetns

  • Choi, Jong-Suk;Kim, Mun-Sang;Lee, Chong-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1921-1926
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    • 2003
  • We build a local minimum free motion planning for mobile robots considering dynamic environments by simple sensor fusion assuming that there are unknown obstacles which can be detected only partially at a time by proximity sensors and can be cleaned up or moved slowly (dynamic environments). Potential field is used as a basic platform for the motion planning. To clear local minimum problem, the partial information on the obstacles should be memorized and integrated effectively. Sets of linked line segments (SLLS) are proposed as the integration method. Then robot's target point is replaced by virtual target considering the integrated sensing information. As for the main proximity sensors, we use laser slit emission and simple web camera since the system gives more continuous data information. Also, we use ultrasonic sensors as the auxiliary sensors for simple sensor fusion considering the advantages in that they give exact information about the presence of any obstacle within certain range. By using this sensor fusion, the dynamic environments can be dealt easily. The performance of our algorithm is validated via simulations and experiments.

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Fault Plane Solutions for the Recent Earthquakes in the Central Region of South Korea

  • Hoe, Seo-Yun;Kyung, Jai-Bok
    • Journal of the Korean earth science society
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    • v.29 no.5
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    • pp.437-445
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    • 2008
  • We analyzed fault plane solutions of the recent twenty-two earthquakes which occurred from 2004 to 2006 in the central part of the Korean Peninsula by using P- and S-wave polarities along with SH/P amplitude ratios. The fault plane solution shows that strike-slip fault is dominant here, especially for the events with local magnitude equal to or greater than 3.0. However, some events with local magnitude less than 3.0 show normal fault or strike-slip fault with normal components. In the case of strike-slip fault, its orientation is almost in the direction of NNE-SSW to NE-SW almost parallel to the general trend of faults, while the compressional axis of the stress field trends ENE to E-W. The result is almost consistent with the stress field in and around the Korean peninsula, as reported previously. We cannot give any appropriate explanations to the normal faulting events along the western offshore and inland areas whether it is related to the local stress changes or tectonically unidentified extensional structures. Thus, an extension of investigations is desirable to clarify the cause of such phenomena.