• 제목/요약/키워드: Local Light

검색결과 663건 처리시간 0.028초

선형유도모터형식 경전철 신호제어시스템 표준사양 연구 (Signalling System Standardization for Linear Induction Motor Type Light Rail Transit)

  • 조봉관;황현철;조홍식;홍재성;류상환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1183-1184
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    • 2007
  • Light Rail Transit (LRT) is optimized vehicle system for complex urban circumstance. LRT systems have many merits such as improved accuracy and safety. There are many LRT systems such as monorail, tram, automated guideway transit, linear induction motor propulsion and so on. These systems have been operated in Japan and other advanced countries. In Korea, local government has many projects to apply the advanced LRT system. But there are no standards regulation, performance test regulation and construction regulation for monorail system, linear induction motor system and tram in Korea. We expect that standardization brings economical construction and safety. The linear induction motor system has been usually applied to subway in Japan and ART(Advanced Rapid Transit) in Canada. In Korea, the linear induction motor system has been adopted for Yong-In LRT and currently under construction. This paper presents signalling system and TCMS(train control and monitoring system) of linear induction motor system.

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Gapped Nearly Free-Standing Graphene on an SiC(0001) Substrate Induced by Manganese Atoms

  • Hwang, Jinwoong;Lee, Ji-Eun;Kang, Minhee;Park, Byeong-Gyu;Denlinger, Jonathan;Mo, Sung-Kwan;Hwang, Choongyu
    • Applied Science and Convergence Technology
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    • 제27권5호
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    • pp.90-94
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    • 2018
  • The electron band structure of manganese-adsorbed graphene on an SiC(0001) substrate has been studied using angle-resolved photoemission spectroscopy. Upon introducing manganese atoms, the conduction band of graphene, that is observed in pristine graphene indicating intrinsic electron-doping by the substrate, completely disappears and the valence band maximum is observed at 0.4 eV below Fermi energy. At the same time, the slope of the valence band decreases by the presence of manganese atoms, approaching the electron band structure calculated using the local density approximation method. The former provides experimental evidence of the formation of nearly free-standing graphene on an SiC substrate, concomitant with a metal-to-insulator transition. The latter suggests that its electronic correlations are efficiently screened, suggesting that the dielectric property of the substrate is modified by manganese atoms and indicating that electronic correlations in grpahene can also be tuned by foreign atoms. These results pave the way for promising device application using graphene that is semiconducting and charge neutral.

Design and Fabrication of an Off-axis Elliptical Zone Plate in Visible Light

  • Anh, Nguyen Nu Hoang;Rhee, Hyug-Gyo;Kang, Pilseong;Ghim, Young-Sik
    • Current Optics and Photonics
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    • 제6권1호
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    • pp.44-50
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    • 2022
  • An off-axis zone plate is able to focus on a single order while neglecting the zeroth order in a visible imaging system. This allows one to enhance the contrast quality in diffractive images, which is the major advantage of this type of zone plate. However, most previous reflection zone plates are used in focusing X-rays with a small grazing incident angle and are intricately designed with the use of a local grating period. In this study, we suggest the design of an off-axis elliptical zone plate (EZP) that is used to focus a monochromatic light beam with separation between the first and unfocused orders under a large grazing incident angle of 45°. An assumption using the total grating period, which depends on the average and constant grating period, is proposed to calculate the desired distance between the first and zeroth order and to simplify the construction of a novel model off-center EZP. Four diffractive optical elements (DOEs) with different parameters were subsequently fabricated by direct laser lithography and then verified using a performance evaluation system to compare the results from the assumption with the experimental results.

부산 감천문화마을 재생을 위해 도입된 공공미술의 지역활성화 효과 (The Local Revitalization Effects of Public Arts Introduction to Gamcheon Culture Village Regeneration)

  • 박재현;이연숙
    • 한국주거학회논문집
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    • 제25권5호
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    • pp.33-41
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    • 2014
  • Today, modern society pursues the paradigm of creative city and regeneration. Cultural regeneration of revitalizing locality by utilizing culture catches attention, is a major approach. Public arts is considered as a catalyst of cultural regeneration, and it inspires vitality to declined districts. Gamcheon Culture Village, Busan has accelerated propagation of revitalization only in recent couple of years, and it has been developing with residents' participation continuously. The purpose of this research is to analyse the revitalizing effects of public arts introduction to Gamcheon Culture Village regeneration. In specific, social, cultural, economical, physical and environmental revitalization effects of the village were defined. The research method is questionnaire survey and 320 reponses from residents and visitors were collected. Data were statistically analyzed with SPSS18.0. The effects of public arts introduction to Gamcheon Culture Village regeneration are positive overall. However, according to the districts of the village, having diversity of art projects in both quantity and quality, the perceptions were different. Regeneration with utilizing public arts for revitalizing declined district, the Gamcheon case shed light on the future. The research indicated the value of public arts and some strategies of allocating art projects.

Standards of architectural design for the ecological certification of the rural settlements

  • Kavas, Kemal Reha;Danaci, Hacer Mutlu;Cal, Isa
    • Advances in Energy Research
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    • 제7권1호
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    • pp.53-66
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    • 2020
  • Before the industrial revolution architecture has been shaped by the natural and cultural inputs. Local constraints become more effective determinants of architecture in the rural contexts because by being disengaged from the webs of transportation and communication, rural settlements have achieved sustainability in difficult conditions. The examples of rural settlement and architecture have provided sustainability through integration with natural inputs within the geographical context because they have reached the goals of ecological design within the local constraints. Although this feature of the rural cultural landscapes has been emphasized frequently, tangible standards could not be developed in order to interpret their ecological design principles from the perspectives of the contemporary building sector and planning. However, the historical experience indicates that the sustenance of ecological performance can be possible as a result of integrated planning at the overall scale of the settlement. Therefore, the existing standards are not qualified for interpreting the rural contexts. This study develops a method for analysing, interpreting and evaluating traditional rural settlements and certifying new implementations in the rural environments in the light of the given literature review, discussion and methodological proposal.

LED Backlight Driving Circuits and Dimming Method

  • Kwon, Oh-Kyong;Jung, Young-Ho;Lee, Yong-Hak;Cho, Hyun-Suk;Nam, Ki-Soo;In, Hai-Jung
    • Journal of Information Display
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    • 제11권4호
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    • pp.173-181
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    • 2010
  • In this paper, light-emitting-diode (LED) backlight driving circuits and dimming method for medium-sized and large liquid crystal displays (LCDs) are proposed. The double loop control method, the intelligent-phase-shifted PWM dimming method, the fast-switching current regulator, and the current matching techniques are proposed to improve not only the current regulation characteristics and the power efficiency but also the current matching characteristics and the transient response of the LED current. The brightness of the backlight using the proposed local dimming method was determined from the histogram of the local block to reduce the power consumption of the backlight without image distortion. The measured maximum power efficiency of the LED backlight driving circuit for medium-sized LCDs was 90%, and the simulation results showed an 88% maximum power efficiency of the LED backlight driving circuit for large LCDs. The maximum backlight power-saving ratio of the proposed dimming method was 41.7% in the simulation with a high-contrast image. The experiment and simulation results showed that the performance of LEDs as LCD backlight units (BLUs) improved with the proposed circuits and method.

Factors Affecting the Extent of Economic Empowerment of Women in Farm Households: Experiences from Rural Bangladesh

  • Parveen, Shahnaj;Leonhauser, Ingrid-Ute
    • International Journal of Human Ecology
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    • 제9권2호
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    • pp.117-126
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    • 2008
  • The study identifies gender stereotypes, examines the level of women's economic empowerment at the household level and explores the influence of factors on it. Data were collected from 159 randomly selected farm women using both qualitative and quantitative survey methods between January and March 2007 from three villages of the Mymensingh District of Bangladesh. Four key informants (2 local leaders and 2 development personnel) were questioned to elicit views in the light of boosting women's empowerment. Five constructs of empowerment covering 30 indicators were aggregated together to develop a cumulative economic empowerment index (CEEI) to obtain multidimensional views of women's empowerment. The findings show that there were some prejudices against women in allocating divisions of labour and access to education, food, property, decision-making and institutions. The distribution of the CEEI demonstrates that the majority of the respondents (86%) had a low to moderate level of empowerment. A multiple regression analysis showed positive significant effects of education, training, media contact and freedom of mobility on women's CEEI, while domestic abuse restrained it. It is concluded that interventions by development agencies in co-ordination with the local community was necessary to attain women's self-reliance in the study area. Development actors can undertake some core strategies to enhance women's level of awarencess, knowledge, skills, and productive resources through providing training, loans, and information. To change traditional beliefs, it is important to create awareness of various gender issues amongst rural people through different methods and media.

Determinants of Economic Segregation and Spatial Distribution of Poverty

  • Park, Yoonhwan
    • 유통과학연구
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    • 제17권3호
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    • pp.21-30
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    • 2019
  • Purpose - While many related prior studies have focused on the segregation by race and ethnicity, the academic interest in the separation of residence by income and social class is gradually increasing. This study aims to not only investigate spatial pattern of economic segregation and poverty rate in South Korea, but also shed light on what affect residential distribution of the poor. Research design, data, and methodology - The unit of analysis is Si-Gun-Gu municipal level entities of South Korea. Most demographic, socioeconomic, and residential variables were derived from Korean Census Data in 2015. In order to examine spatial patterns of economic segregation and poverty rate in South Korea, a series of measurements and visualization was conducted through the Geo-Segregation Analyzer and ArcGIS programs. Determinants of economic segregation and local poverty rates were investigated by regression analyses using STATA. Results - The spatial patterns of areas with high poverty rates were extremely clustered, while the distribution of areas with high economic segregation was relatively evenly distributed. Demographic, residential, and local factors appeared to affect whether the poor live in particular area or spread evenly. Conclusions - The factors that raise the poverty rate result in lower level of economic segregation, while factors that reduce the poverty rate lead to severe level of economic segregation.

광 섬유내의 광유도 위상격자가 형성되는 자기조직 역학에 관한 연구 (Self-Organized Dynamics of Photoinduced Phase Grating formation in Optical Fibers)

  • 안성혁
    • 한국광학회지
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    • 제4권4호
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    • pp.464-473
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    • 1993
  • 본 논문에서는 광섬유에 아르곤 레이저 빔이 입사될 때 생기는 위상격자 형성에 관한 역학을 다룬다. 간단한 쌍광자 표백모델(two-photon bleaching model)을 이용하여 위상격자가 시간이 지남에 따라 이상적인(ideal) 격자로 자기조직됨(self-organized)을 보인다. 광섬유의 각점에서의 시간에 따른 상태전개는 하나의 보편 매개변수(universial parameter)에 의해 나타내어지고 또한 이 광섬유계를 기술하는 연립편미분 방정식이 이 매개변수에 의해 연립 상 미분 방정식으로 간소화 된다. 이 연립 상 미분 방정식을 이용하여 위상격자가 자라나는 상태는 한 고정점(a fixed point)를 향해 가는 과정이고 이 고정점은 완벽히 위상맞춤(phase-matched)된 격자에 해당된다는 것을 보인다.

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도시공원의 정체성 확립을 위한 도입시설 연구 (Searching for Facilities and Service Programs for the Establishment of Urban Park Identification)

  • 홍성권;이민우;이상민;안명준
    • 한국조경학회지
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    • 제35권5호
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    • pp.29-36
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    • 2007
  • The new Urban Park Regulation encourages local governments to introduce new types of urban parte such as historic parte, cultural parks and neighborhood parte. However ambiguity among those parks in terms of main facilities and providing recreational programs makes it difficult for local governments, as well as landscape designers and planners, to adopt this new regulations. In this light, the present study aims to search for park facilities and programs defined by the new regulations, in order to satisfy users' demands for those parks with consideration to parks' unique characteristics. For these purposes, a conjoint analysis was carried out with three hundreds participants. Sampled participants include the citizens of Seoul as well as current residents of Paju. The study results indicate that participants would like to have distinctive programs and facilities at these three new types of parks. However, no considerable differences were observed among the levels of programs and facilities participants wish to have, due to unfamiliarity with, in particular, cultural and historic parks. Despite this insignificant difference among attribute levels, study results clearly suggest that residents wold like to have new types of facilities and recreational programs.