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Design of a GIS-Based Distribution System with Service Consideration (서비스수준을 고려한 GIS기반의 차량 운송시스템)

  • 황흥석;조규성
    • Korean Management Science Review
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    • v.18 no.2
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    • pp.125-134
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    • 2001
  • This paper is concerned with the development of a GIS-based distribution system with service consideration. The proposed model could be used for a wide range of logistics applications in planning, engineering and operational purpose for logistics system. This research addresses the formulation of those complex prob1ems of two-echelon logistics system to plan the incorporating supply center locations and distribution problems based on GIS. We propose an integrated logistics model for determining the optimal patterns of supply centers and inventory allocations (customers) with a three-step sequential approach. 1) First step, Developing GIS-distance model and stochastic set-covering program to determine Optimel pattern of supply center location. 2) Second step, Optimal sector-clustering to support customers. 3) Third step, Optimal vehicle rouse scheduling based on GIS, GIS-VRP In this research we developed GUI-tree program, the GIS-VRP provide the vehicle to users and freight information in real time. We applied a set of sample examples to this model and demonstrated samp1e results. It has been found that the proposed model is potentially efficient and useful in solving multi-depot problem through examples. However the proposed model can provide logistics decision makers to get the best supply schedule.

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On the Optical Characteristics of Solar X-Ray Telescopes: Possible Relation between Vignetting Effect and Mirror Scattering

  • Shin, Jun-Ho;Sakurai, Takashi
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.87.1-87.1
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    • 2011
  • Since early 90's, the solar X-ray telescopes such as Yohkoh SXT and Hinode XRT have observed coronal magnetic structures on the Sun's surface in the range of about $40'{\times}40'$ field-of-view (FOV) covering the full solar disk. Thus it has been stressed by the scientists that the optical structure of solar telescopes should be designed with care for improving the uniformity over a wide FOV. There would be, however, no unique solution in designing the optical system of a telescope for overcoming perfectly the problem of off-axis response variation. As a consequence, the correction of optical imperfectness of telescopes has become an important calibration step that should be performed beforehand when the observed images are to be used for photometric purposes. In particular, a special care should be taken when performing the temperature analysis with thin and thick filters for flaring activities observed at the periphery of the full FOV. From the analyses of both pre-launch calibration and in-flight observation data, the optical characteristics for describing the performance of solar X-ray telescopes, especially in view of their energy dependence, will be introduced and discussed in our presentation.

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Pin Power Reconstruction of HANARO Fuel Assembly via Gamma Scanning and Tomography Method

  • Seo, Chul-Gyo;Park, Chang-Je;Cho, Nam-Zin;Kim, Hark-Rho
    • Nuclear Engineering and Technology
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    • v.33 no.1
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    • pp.25-33
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    • 2001
  • To determine the pin power distribution without disassembling, HANARO fuel assemblies are gamma-scanned and then the distribution is reconstructed tv using the tomography method. The iterative least squares method (ILSM and the wavelet singular value decomposition method (WSVD) are chosen to solve the problem. An optimal convergence criterion is used to stop the iteration algorithm to overcome the potential divergence in ILSM. WSVD gives better results than ILSM , and the average values from the two methods give the best results. The RMSE (root mean square errors) to the reference data are 5.1, 6.6, 5.0, 6.5, and 6.4% and the maximum relative errors are 10.2, 13.7, 12.2, 13.6, and 14.3%, respectively. It is found that the effect of random positions of the pins is important. Although the effect can be accommodated by the iterative calculations simulating the random positions, the use of experimental equipment with a slit covering the whole range of the assembly horizontally is recommended to obtain more accurate results. We made a new apparatus using the results of this study and are conducting an experiment in order to obtain more accurate results.

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A Social Study Approach to Education for Environmental Administration Specialists (환경행정전문가 양성을 위한 사회교육적 접근)

  • 신현덕
    • Hwankyungkyoyuk
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    • v.2 no.1
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    • pp.100-106
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    • 1991
  • Environmental professional education in Korea has been mostly concentrated on the scientific and technological approaches to environmental problems. Many undergraduate majors in environmental engineering or sciences are designed to produce more technical manpowers in environmental fields. Most graduate schools on the environment also place an emphasis on teaching the technical aspects of environmental problems. Some environmental administration related courses, such as environmental law, environmental administration, environmental policy, environmental economics, environmental impact assessments, etc. are partically reflected in some curricula of very limited graduate or undergraduate environment majors. However, teaching environmental administration related courses in science or engineering major institutions has not been successfully carried out so far because lack of interests in such courses by most students and the shortage of competent teachers as well. Furthermore, those courses are not widely accepted by the departments of law, political science, public administration, etc. because their major interests are not in the environment-oriented. Environmental problems cannot be solved by the technical approach along. They should be systematically dealt with through interdisciplinary or multidisciplinary approaches, including natural and social sciences covering all relevant disciplines. in this respect, undergraduate environmental education should preferably cover broader courses on the environment, and the education for environmental professionals, including environmental administration specialists, is preferably handled by graduate schools offering many specialty area courses. Education for environmental administration specialist at graduate level is urgently needed in order to supply the competent manpower at government, business, and private organization levels dealing with environmental administration related problem. This is a new challenging area and the education for such specialists will become more important in the near future than technical manpowers which we ate now concentrating on their education.

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A basic study on Improvement for Biotops Area Ratio through the Post Evaluation Plan for Outdoor Space of Apartment Housings (공동주택의 외부공간 시공 후 평가를 통한 생태면적률 개선 방안도출을 위한 기초 연구 - 현장시공시 생태면적률 공간유형 반영을 중심으로 -)

  • Jang, Dae-hee;Kim, Hyeon-soo;Kang, Byoung Keun
    • KIEAE Journal
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    • v.10 no.6
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    • pp.91-96
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    • 2010
  • The problem of urban climate change and destruction of wildlife habitats space which is becoming more serious day by day, has to do with the impervious area(surface area) in urban space. The destruction of natural ground and indiscreet soil covering due to compact development is causing urban desertification in urban residential areas. With biotops area ratio being variously used and extended as a pre planning index, this study aims to analyze the elements of biotop area ratio that need to be supplemented in order to emerge as a realistic planning index for post evaluation measure and not act only as a examining tool in the planning stage. In particular, this study aims to examine the possibility of biotops area ratio to be used as a system to evaluate the outer space of apartment housings, in which biotops area ratio is most actively used, as a tool to secure ecological soundness of the development area after construction is finished.

Some Comments on Revision of Memorandum of Understanding on Port State Control in Asia-Pacific Region and Actualities of Korean PSC Regime (아태지역항만국통제에 관한 양해각서의 개정과 비판)

  • 강동수
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.7 no.3
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    • pp.93-106
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    • 2001
  • Whether a ship is sub-standard or not shall be finally decided by the minimum standards laid down in international conventions or national standards having the same effects. The flag State is primarily responsible for implementing these standards as far as its own ships are concerned. And the port State shall, in the exercise of its rights under international law, take appropriate measures (including detention of ships identified as sub-standard), which are regarded as port State's supplementary role aiming at implementing these standards. The international standards are implemented by the regional co-operation in the form of the MOU(Memorandum of Understanding) on Port State Control in the Asia-Pacific Region on the ground that the PSC enforcement of only one country does not enable the eradication of sub-standard ships. Recently, EQUASIS which is an international database covering the whole world fleet change the regionalism of PSC into the globalization of PSC. However, there are many problems in Tokyo MOV and Korean PSC regime. In order to ensure the implementation of the standards laid down in international conventions and Tokyo MOU, the Korean and other country in Asia-Pacific shall settle the alienation from the actuality of the law, namely the problem of maritime administrative structure of non unifying PSC affairs.

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Education of Power Electronics in Japan

  • Matsui, Mikihiko;Ueda, Akiteru;Oguch, Kuniomi
    • Journal of Power Electronics
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    • v.2 no.4
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    • pp.268-277
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    • 2002
  • Power electronics is an interdisciplinary area that is interstitial to all of the major disciplines of electrical engineering including power, electronics and control. Today, the covering field of power electronics has more widely spread out with the help of ever evolving microelectronics and computer science. Whereas, in Japan the tendency is becoming remarkable nowadays that science, especially "mathematics" and "hardware work", are falling into disfavor with the young people. For these reasons, it has become a very important problem to find out "what are the truest essentials of power electronics\ulcorner" and "How to give students incentives to learn power electronics\ulcorner " from an educational point of view In under-graduate and graduate courses in universities. On the other hand, the power electronics engineers in companies are always required to comply with the ever changing trend of global and open market. However, it takes long time to cultivate their skills. Against the background, "The Cooperative Research Committee on Education of Power Electronics" was established in the IEEJ Industry Applications Society during 2000-2001. The present status of the power electronics education in Japan is surveyed in this paper, and some problems with remedy are pointed out based on the discussions performed in the committee.sed on the discussions performed in the committee.

Utilizing Pedicled Muscle Flap for Defect Coverage after External Auditory Canal Cancer Resection (외이도에 발생한 악성종양에서 유경근육피판을 이용한 결손 재건)

  • Lee, Kangwoo Nathan;Kim, Eun Key
    • Archives of Craniofacial Surgery
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    • v.12 no.1
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    • pp.37-42
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    • 2011
  • Purpose: Cancer arising from the external auditory canal is a rare disease. A lesion that seems harmless in someway, can be lethal when inadequately excised, the tumor may infiltrate nerves, the parotid and auditory tissues before re-invading the skin. Wide resection of the lesion surrounding the structure and reconstruction with an adequate plan is crucial for the treatment of this disease. Methods: Two patients with external auditory canal cancer were treated with muscle flaps and skin grafts. Lateral temporal bone resection (LTBR) was performed for complete resection of the cancer. The defect cavity was obliterated with highly vascularized tissue using pedicled sternocleidomastoid muscle, and temporalis muscle individually, combined with full thickness skin graft for covering the skin defect of the ear. Results: Clear resection margin was obtained, and both patients showed disease free survival during the follow up. There was no complications of hematoma, infection, flap loss, or wound problem in both patients. Both patient received radiation therapy, there was no osteoradionecrosis or any other complication related to radiation therapy. Conclusion: Utilizing pedicled muscle flaps for managing defects after wide resection of the external auditory canal cancer is an effective method for managing this difficult disease.

Real-time estimation of break sizes during LOCA in nuclear power plants using NARX neural network

  • Saghafi, Mahdi;Ghofrani, Mohammad B.
    • Nuclear Engineering and Technology
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    • v.51 no.3
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    • pp.702-708
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    • 2019
  • This paper deals with break size estimation of loss of coolant accidents (LOCA) using a nonlinear autoregressive with exogenous inputs (NARX) neural network. Previous studies used static approaches, requiring time-integrated parameters and independent firing algorithms. NARX neural network is able to directly deal with time-dependent signals for dynamic estimation of break sizes in real-time. The case studied is a LOCA in the primary system of Bushehr nuclear power plant (NPP). In this study, number of hidden layers, neurons, feedbacks, inputs, and training duration of transients are selected by performing parametric studies to determine the network architecture with minimum error. The developed NARX neural network is trained by error back propagation algorithm with different break sizes, covering 5% -100% of main coolant pipeline area. This database of LOCA scenarios is developed using RELAP5 thermal-hydraulic code. The results are satisfactory and indicate feasibility of implementing NARX neural network for break size estimation in NPPs. It is able to find a general solution for break size estimation problem in real-time, using a limited number of training data sets. This study has been performed in the framework of a research project, aiming to develop an appropriate accident management support tool for Bushehr NPP.

JPEG Pleno: Providing representation interoperability for holographic applications and devices

  • Schelkens, Peter;Ebrahimi, Touradj;Gilles, Antonin;Gioia, Patrick;Oh, Kwan-Jung;Pereira, Fernando;Perra, Cristian;Pinheiro, Antonio M.G.
    • ETRI Journal
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    • v.41 no.1
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    • pp.93-108
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    • 2019
  • Guaranteeing interoperability between devices and applications is the core role of standards organizations. Since its first JPEG standard in 1992, the Joint Photographic Experts Group (JPEG) has published several image coding standards that have been successful in a plethora of imaging markets. Recently, these markets have become subject to potentially disruptive innovations owing to the rise of new imaging modalities such as light fields, point clouds, and holography. These so-called plenoptic modalities hold the promise of facilitating a more efficient and complete representation of 3D scenes when compared to classic 2D modalities. However, due to the heterogeneity of plenoptic products that will hit the market, serious interoperability concerns have arisen. In this paper, we particularly focus on the holographic modality and outline how the JPEG committee has addressed these tremendous challenges. We discuss the main use cases and provide a preliminary list of requirements. In addition, based on the discussion of real-valued and complex data representations, we elaborate on potential coding technologies that range from approaches utilizing classical 2D coding technologies to holographic content-aware coding solutions. Finally, we address the problem of visual quality assessment of holographic data covering both visual quality metrics and subjective assessment methodologies.