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Flora and Distribution of Mt. nam Park, Seoul (서울 남산공원의 식물상과 그 분포)

  • 길봉섭;유현경;김병삼;김현철;전의식;김영식;김창환;윤경원
    • The Korean Journal of Ecology
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    • v.21 no.5_3
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    • pp.603-631
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    • 1998
  • Flora and distribution of vascular plants included introduced species of Mt. Nam park in Seoul were investigated from 1997 to 1998. The flora was composed of 112 families, 338 genera, 487 species, 1 subspecies, 60 varieties, 11 forma or 559 taca. Whole taxa of Mt. Nam calculated with the other reports were recorded 125 families, 461 genera, 832 species, 2 subspecies, 115 varieties, 14 forma or 963 taxa. Mt. nam area has lost its properties because of road and promenade construction, several park reclaimation, introduction of foreign species and exotic plants, and so on. The urbanized index (UI) was comparatively high at 18.3%. Eupatorium rugosum which shown high shade tolerance comparatively was occupied dominantly in road sides. The natural ecosystem and biodiversity of Mt. Nam were under threatened by introduced species. DBH mode of Pinus densiflora community was shown bell shape but that of Quercus mongolica was shown reverse J shape, therefore, it will be occupied in the future this area dominantly by Q. mongolica community. However the vegetation of Mt. nam park area are repressing by superior position in their growth of introduced species included R. pseudo-acacia, Ailanthus altissima and E. rugosum, etc.

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Novel Switching Strategy of 1MVar STATCON using Cascade Multilevel Voltage Source Inverter for FACTS Application (FACTS 적용을 위한 직렬형 멀티레벨 전압형 인버터를 사용한 1MVar STATCON의 새로운 스위칭기법)

  • Min, Wan-Gi;Min, Jun-Gi;Choe, Jae-Ho
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.48 no.12
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    • pp.691-700
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    • 1999
  • This paper proposes a novel switching strategy of 1Mvar STATCON using cascade multilevel H-bridge inverter(HBI) for FACTS application. To control the reactive power instantaneously, the d-q dynamic system model is described and analyzed. A single pulse pattern based on the SHEM(Selective Harmonic Elimination Method) technique is determined from the look-up table to reduce the line current harmonics and a rotating fundamental frequency switching scheme is presented to adjust the DC voltage of each inverter capacitor at the same value. So the voltage unbalance problem between separately DC bus voltage is improved by using the proposed switching scheme. As a result, the presented inverter configuration not only reduces the system complexity by eliminating the isolation at the AC input side transformer but also improves the dynamic response to the step change of reactive power.

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The Study on Pictures of Daoist exercises of Euibangyoochi (『의방유취』의 도인도(導引圖)에 관한 연구)

  • Jung, Ji-Hun;Han, Bong-Jae;Kim, Dong-Ryul
    • The Journal of Korean Medical History
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    • v.27 no.1
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    • pp.41-50
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    • 2014
  • This article is about the study on pictures of Daoist exercises described in Euibangyoochi- which is the largest book in Joseon Dynasty. Daoist exercises are the active exercises to prevent disease by training their body. In Euibangyoochi, there are lots of information of Daoist exercises. Specially, pictures of Daoist exercises are from '$q{\acute{u}}xi{\bar{a}}nhu{\acute{o}}r{\acute{e}}$nxīnf$\bar{a}$ng'. There are movements of body, methods of respiration, tooth brushing, and hand clapping in Daoist exercises this book. On the other hand, the pictures of Daoist exercises were composed with simple explanations so that readers actually might follow the directions at ease. There are 8 pictures of Daoist exercises left in Euibangyoochi. Those are Daoist exercises tradition in the midium of Joseon Dynasty which led to Hwalinshimbang of Yi-hwang. Also with the trend of preventing disease in these days, the importance of Daoist exercises is emphasized and these pictures became a tool of teaching the old Daoist exercises.

Empty Container Distribution and reassignment problem due to demand of freight depot (국내 화물 거점별 수요에 따른 공컨테이너 분배 및 재배치 연구)

  • Park, Jong-Won;Shin, Jae-Young
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2009.10a
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    • pp.185-186
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    • 2009
  • According to increase of container transportation, demands of empty container handling has been increasing, so research of empty container has been studied steadily. However, the handling of containers and empty containers is not handled simultaneously. Moreover, as Korean ICD(Inland Container Depot) and ODCY(Off-Dock Container Yard), the inland depot in many environments, relocation research due to demand of empty container has not been studied sufficiently. This paper formulates and analyzes logical mathematical relocation model according to demands of empty container which are required in container terminal, ICD, and ODCY as cargo depots. This paper also aims to help reduce cost by improving q current empty container relocation as same as the past procedure.

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Advanced Method for an Initial Pole Position Estimation of a PMLSM (PMLSM의 개선된 초기 자극위치 추정방법)

  • Lee Jin-Woo
    • The Transactions of the Korean Institute of Power Electronics
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    • v.10 no.2
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    • pp.124-129
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    • 2005
  • This paper presents an advanced method for an initial pole position estimation of a Permanent Magnet Linear Synchronous Motor(PMLSM) that has an accurate incremental encoder for servo applications but does not have Hall sensors as a magnetic pole sensor. By appropriately using the secant method as a numerical method the proposed algorithm finds either of two zero force positions and then the correct d-axis by applying a q-axis test current. It only requires the tuned current controller and the relative position information md so it can be simply applicable to a rotary PMSM. The experimental results show the validity of the proposed method, which has an excellent performance with respect to an accurate pole position estimation under the minimal moving distance(average of about 85㎛) during the estimation process.

3차원적 도핑 분포 측정을 위한 SCM 응용 방법 (The SCM Method for Three-Dimensional Dopant Profiles)

  • Lee Jun-Ha;Lee Hoong-Joo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.1
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    • pp.7-11
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    • 2006
  • Through SCM modeling, we found that the depletion layer in silicon was of a form of a spherical capacitor with the SCM tip biased. Two-dimensional (2D) finite differential method code with a successive over relaxation (SOR) solver has been developed to model the measurements by SCM of a semiconductor wafer that contains an ion-implanted impurity region. Then, we theoretically analyzed the spherical capacitor and determined the total depleted-volume charge Q, capacitance C, and the rate of capacitance change with bias dC/dV. It is very important to observe the depleted carriers' movement in the silicon layer by applying the bias to the tip. So, we calculated the depleted-volume charge, considering different factors such as tip size, oxide thickness, and applied bias (dc+ac), which have an influence on potential and depletion charges.

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Robust algorithm for estimating voltage stability by the modified method of sensitivity index dP/de of real value on voltage vector (전압벡터의 유효분 감도지표 dP/de 수정법에 의한 견고한 전압안정도 평가에 관한 연구)

  • 송길영;김세영;김용하
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.1
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    • pp.1-8
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    • 1996
  • Recently, much attention has been paid to problems which is concerned with voltage instability phenomena and much works on these phenomena have been made. In this paper, by substituting d $P_{k}$ d $e_{k}$ ( $v^{\rarw}$= e +j f) for $P_{k}$ in conventional load flow, direct method for finging the limit of voltage stability is proposed. Here, by using the fact that taylor se- ries expansion in .DELTA. $P_{k}$ and .DELTA. $Q_{k}$ is terminated at the second-order terms, constraint equation (d $P_{k}$ d $e_{k}$ =0) and power flow equations are formulated with new variables .DSLTA. e and .DELTA.f, so partial differentiations for constraint equation are precisely calculated. The fact that iteratively calculated equations are reformulated with new variables .DELTA.e and .DELTA.f means that limit of voltage stability can be traced precisely through recalculation of jacobian matrix at e+.DELTA.e and f+.DELTA.f state. Then, during iterative process divergence may be avoid. Also, as elements of Hessian mat rix are constant, its computations are required only once during iterative process. Results of application of the proposed method to sample systems are presented. (author). 13 refs., 11 figs., 4 tab.

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Parameter and Brightness Characteristic of Antena according to Coil turns on Electrodeless Fluorescent Lamp (무전극 램프 안테나의 권선수에 따른 휘도와 파라미터 특성)

  • Yang, Jong-Kyung;Choi, Gi-Seung;Pack, Gwang-Hyeon;Choi, Yong-Sung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 2004.11a
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    • pp.281-284
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    • 2004
  • In Recent, it became necessary to envelope the technology about electrodeless fluorescent lamp according to demand of the electrodeless fluorescent lamp system that used higher efficiency and advantage of long-lifetime. Especially, in the electrodeless fluorescent lamp which used H-mode, efficiency of lamp is decided from matching parameter of antena and inverter So it is of the utmost importance to design antena and inverter. Therefore, this paper used a transformer principle for efficiency rising of electrodeless fluorescent lamp and interpreted an equivalent circuit, used an impedance analyzer in order to confirm a performance enhancement of lamp along design of antenna, and confirmed parameter characteristic of R, L, C, Z, Phase, Q-factor along a change of magnetic flux density. Also, this paper confirmed a luminance characteristic of electrodeless lamp along parameter change with measuring optical characteristic along a change of magnetic flux density.

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Selection of Optimum Fulcrum Type for Measurement and Geo-statistical Analyze of Elevation within Rice Paddy Field (수도작 포장의 고저차 측정을 위한 최적 받침대 선정)

  • Sung J. H.;Jang S. W.
    • Journal of Biosystems Engineering
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    • v.30 no.5 s.112
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    • pp.268-273
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    • 2005
  • This study was conducted to investigate the specificities of four fulcrum types for geo-statistical analysis of elevation within rice paddy field. In Korea, the spaces between inter-rows and between hills for rice transplanting are 30cm and 11cm to 14cm, respectively. So, the size and shape of fulcrum for field elevation measurement should be considered according to the inter-row and the hill spaces. Four kinds of fulcrum were chosen such as round-shape with 2.5cm diameter, circular-shape with 10cm diameter, 10cm (one third of inter-row space) by 24cm (double of hill space) rectangular-shape, and 20cm (two-thirds of inter-row space) by 24cm rectangular-shape. The resulting descriptive statistics couldn't determine the best fulcrum type to measure the rice paddy field elevation. But the results of geo-statistical analysis could determine the best fulcrum type. In the case of 10cm by 24cm rectangular-shape fulcrum, Nugget and range, meaning measurement error and/or noise, and limit of spatial connection, respectively, were minimum; Q value meaning weight of spatial structure and $r^2$ value were minimum, and residual sum of squares was minimum. It means that 10cm by 24 cm rectangular-shape fulcrum could best describe the rice paddy field elevation.

A Study on Self-Assessment Model Development for the Local-Industry Promotion Project (향토산업육성사업의 자가진단모델 개발에 관한 연구)

  • Son, Eun-Il;Satohi, Hoshino
    • Journal of Korean Society of Rural Planning
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    • v.18 no.3
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    • pp.43-55
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    • 2012
  • This study proposes a self-assessment model and its implementing procedure for the local industry promotion project, the purpose of which is to develop strategies for successful carrying-out of the project by diagnosing carrying capacities of its interested parties. The model, developed principally based on Eckes' $Q{\times}A=E$ Evaluation Model, was applied to 85 project-concerned persons which had been participated in the local industry promotion project from 2009 to 2011. Through the applicability test works of this model, its usefulness and importance for better implementation of the project was ascertained, especially to reflect cultural changes of project actors positively. The actors' recognition level of the project should be one of the critical factors for the successful implementation of the local industry promotion project. So, the higher understanding in the local industry promotion project, the more positive assessment in all respects of the project. Finally, it should be considered that the assessment results might differ for the same assessment standards from assessers' different perspectives.