• Title/Summary/Keyword: 공간영역

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A Propose on the Propagation Prediction Model for Service in the Sea of CDMA Mobile Communication (CDMA 이동통신의 해상 서비스를 위한 전파예측모델 제안)

  • Kim, Young-Gon;Park, Chang-Kyun
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.6
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    • pp.106-112
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    • 2001
  • Unfortunately, the area without economical efficiency, especially the far distance sea, is much lower than that of a urban area-built-up area. It should be promoted the equivalent level to a urban area in the light of future-oriented universal service. Actually, Because propagation environment of mobile communication in the sea is greatly different from that for inland focused on built-up area, a propagation prediction model in the sea should be distinguished from inland-based one. Accordingly, the purpose of this study is to suggest the propagation prediction model for the sea service as a method to minimize unnecessary facilities investment and maintenance caused by additional or new building of a base station. If mobile phone service for far distance sea is provided by expanding limited communication zone of narrow band CDMA mobile communication whose spread band FA is 1.2288MHz. Suggested propagation prediction model includes five parameters to minimize facilities investment of a base station and maximize channel capacity: equivalent line of sight, chip delay by PN code, antenna altitude, power of base station and gain of antennas. Finally, suggested propagation prediction model is simulated and, the results are examined for its utility by comparing with loss of free space.

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Contents Based Partial Encryption of GIS Vector Map (GIS 벡터맵의 콘텐츠 기반 선택적 암호화 기술)

  • Jang, Bong-Joo;Lee, Suk-Hwan;Moon, Kwang-Seok;Kwon, Ki-Ryong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.5
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    • pp.88-98
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    • 2011
  • Recently, according as the importance of GIS(geography information system) database security is embossed, much researches had been achieved about GIS network security. But most such researches are weak against sourceful illegal reproductions and distributions of GIS vector data map. In this paper, we proposed an efficient layer unit contents based partial encryption technique in the vector map compression domain to prevent illegal distributions and unauthorized accesses. This method achieves a partial encryption about each central coordinate and directional parameters of a MCA(minimum coding attribute) that is created at the vector map compression processing in the vector space. First, the position encryption is applied as permutating randomly the center coordinate of each record that is minimum unit of vector map shape. And second, the direction encryption that changing shapes of vector map topography is applied as encrypting the direction of vertices's coordinates of each record. In experimental results, we confirmed that our proposed method can encipher the large volumed vector map data effectively in low computational complexity. Also, we could minimize the decline of compression efficiency that occurred by conventional contents based encryption schemes using AES or DES algorithms.

Simulation of Energy Resolution of Time of Flight System for Measuring Positron-annihilation induced Auger Electrons (양전자 소멸 Auger 전자 에너지 측정을 위한 Time of Flight의 분해도 향상에 관한 이론적 연구)

  • Kim, J.H.;Yang, T.K.;Lee, C.Y.;Lee, B.C.
    • Journal of the Korean Vacuum Society
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    • v.17 no.4
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    • pp.311-316
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    • 2008
  • Since the presence of the chemical impurities and defect at surfaces and interfaces greatly influence the properties of various semiconductor devices, an unambiguous chemical characterization of the metal and semiconductor surfaces become more important in the view of the miniaturization of the devices toward nano scale. Among the various conventional surface characterization tools, Electron-induced Auger Electron Spectroscopy (EAES), X-ray Photoelectron Spectroscopy (XPS) and Secondary Electron Ion Mass Spectroscopy (SIMS) are being used for the identification of the surface chemical impurities. Recently, a novel surface characterizaion technique, Positron-annihilation induced Auger Electron Spectroscopy (PAES) is introduced to provide a unique method for the analysis of the elemental composition of the top-most atomic layer. In PAES, monoenergetic positron of a few eV are implanted to the surface under study and these positrons become thermalized near the surface. A fraction of the thermalized positron trapped at the surface state annihilate with the neighboring core-level electrons, creating core-hole excitations, which initiate the Auger process with the emission of Auger electrons almost simultaneously with the emission of annihilating gamma-rays. The energy of electrons is generally determined by employing ExB energy selector, which shows a poor resolution of $6{\sim}10eV$. In this paper, time-of-flight system is employed to measure the electrons energy with an enhanced energy resolution. The experimental result is compared with simulation results in the case of both linear (with retarding tube) and reflected TOF systems.

Actual Condition & the Need of Education for Elderly Housing Education Perceived by Adolescents (청소년이 인식하는 중학교 노년기 주생활 교육 실태와 교육 필요도)

  • Lee, Young-Ja;Jang, Sang-Ock
    • Journal of Korean Home Economics Education Association
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    • v.20 no.4
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    • pp.59-75
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    • 2008
  • This study is designed to support the development and the teaching of revised curriculum of 2007 "Technology & Home Economics" by investigating the actual condition and the necessity of education for elderly housing education. Questionnaire survey was conducted with 488 high school students in Gyeongnam in 2008. The data analyzed by descriptive statistics, t-test, One-way ANOVA, Duncan's multiple range test by using SPSS 14 program. The results showed that most of the students were dissatisfied with their middle school education of elderly housing due to the lack of interesting and practical contents. Thus, various teaching-learning methods where student can experience and experiment is needed. Also, the students demanded more of factors of elderly housing, spacing plan, elderly welfare service and less of three-generation housing and senior housing in their elderly housing education. The needs of education contents differed among students depending on variables such as sex, graduated middle school, household income, dwelling space and length of residential years. Therefore, revised 2007 curriculum of "Technology & Home Economics" should include required contents in related chapters. Because there are significant differences among textbooks about elderly housing, further attention needs to be paid to the new textbooks in order to include education contents evenly. At the same time, teachers should organize their teaching contents considering the divergence of variables. The effect of elderly housing education will be maximized if the revised curriculum consists of more experimental activities such as elderly simulation in the local community.

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Fuzzy discretization with spatial distribution of data and Its application to feature selection (데이터의 공간적 분포를 고려한 퍼지 이산화와 특징선택에의 응용)

  • Son, Chang-Sik;Shin, A-Mi;Lee, In-Hee;Park, Hee-Joon;Park, Hyoung-Seob;Kim, Yoon-Nyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.2
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    • pp.165-172
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    • 2010
  • In clinical data minig, choosing the optimal subset of features is such important, not only to reduce the computational complexity but also to improve the usefulness of the model constructed from the given data. Moreover the threshold values (i.e., cut-off points) of selected features are used in a clinical decision criteria of experts for differential diagnosis of diseases. In this paper, we propose a fuzzy discretization approach, which is evaluated by measuring the degree of separation of redundant attribute values in overlapping region, based on spatial distribution of data with continuous attributes. The weighted average of the redundant attribute values is then used to determine the threshold value for each feature and rough set theory is utilized to select a subset of relevant features from the overall features. To verify the validity of the proposed method, we compared experimental results, which applied to classification problem using 668 patients with a chief complaint of dyspnea, based on three discretization methods (i.e., equal-width, equal-frequency, and entropy-based) and proposed discretization method. From the experimental results, we confirm that the discretization methods with fuzzy partition give better results in two evaluation measures, average classification accuracy and G-mean, than those with hard partition.

Development of Generating Technique for Triangular Mesh by using Distinct Element Method (개별요소법을 이용한 삼각망 생성기법 개발)

  • Kim, Nam-Hyeong;Yun, Hyeon-Cheol;Hur, Young-Teck
    • Journal of Navigation and Port Research
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    • v.34 no.5
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    • pp.367-373
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    • 2010
  • When the numerical analysis is carried out, it is necessary to set proper elements as a feature of analysis domains for more accurate simulations. In this study, Distinct Element Method(DEM) is applied, only considering repulsive force and tensile force except for frictional force and resisting force of particle. When the filled particles with initial Quad-tree type is relocated by DEM, a blank space existing among the particles can be minimized because the shape of particle is circular. Finally, it is the effective feature that the centroidal disposion of the particles is similar to an equilateral triangle. Triangular mesh are formed by using the Delaunay triangular technique on these relocated particles, the quality of triangular mesh is more improved by carrying out Laplace interpolations. The compared result of Aspect Ratio before and after the Laplace interpolation is shown that although the quality of triangular mesh made by DEM is good, the later triangular mesh are higher quality than the formers. In this study, although the developed technique takes a longer calculational time than the previous technique to generate triangular mesh, it is considered that the applicable possibility is very high in the generation of finite element mesh about wave analysis and various numerical simulation to need a complex or reappearance of exact topography.

Effective Graph-Based Heuristics for Contingent Planning (조건부 계획수립을 위한 효과적인 그래프 기반의 휴리스틱)

  • Kim, Hyun-Sik;Kim, In-Cheol;Park, Young-Tack
    • The KIPS Transactions:PartB
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    • v.18B no.1
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    • pp.29-38
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    • 2011
  • In order to derive domain-independent heuristics from the specification of a planning problem, it is required to relax the given problem and then solve the relaxed one. In this paper, we present a new planning graph, Merged Planning Graph(MPG), and GD heuristics for solving contingent planning problems with both uncertainty about the initial state and non-deterministic action effects. The merged planning graph is an extended one to be applied to the contingent planning problems from the relaxed planning graph, which is a common means to get effective heuristics for solving the classical planning problems. In order to get heuristics for solving the contingent planning problems with sensing actions and non-deterministic actions, the new graph utilizes additionally the effect-merge relaxations of these actions as well as the traditional delete relaxations. Proceeding parallel to the forward expansion of the merged planning graph, the computation of GD heuristic excludes the unnecessary redundant cost from estimating the minimal reachability cost to achieve the overall set of goals by analyzing interdependencies among goals or subgoals. Therefore, GD heuristics have the advantage that they usually require less computation time than the overlap heuristics, but are more informative than the max and the additive heuristics. In this paper, we explain the experimental analysis to show the accuracy and the search efficiency of the GD heuristics.

A Study on the Name of East Sea in the Francophone Media Source (불어권 언론 매체의 동해 표기 명칭 고찰)

  • Lim, Eunjin;Yi, Saangkyun
    • Journal of the Korean association of regional geographers
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    • v.22 no.4
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    • pp.745-760
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    • 2016
  • The name of a place represents the social and political power relations as well as showing a certain physical space. In particular, the East Sea is not only a representative name of areas represent our country, but also the name of place being in competition with the Sea of Japan internationally. Korea is committed in many ways to spread the name of East Sea in the international community, and gradually expand its name power. The purpose of this study was to investigate the names used in the newspapers and broadcasting in Francophone countries except France by analyzing the newspaper articles and broadcasting contents, and to illuminate how the names of the East Sea produced in France, and the discussion about the names were diffused in Francophone countries and what kind of influence they had on those countries. This study selected Algeria in North Africa, Belgium and Luxembourg in West Europe, and Quebec in Canada for the research areas. As a result, while Algeria in North Africa and Luxembourg are showing inhospitality to the name East Sea, Belgium and Quebec are taking a flexible attitude toward this name. In general, most Francophone countries are provided with press releases from AFP in France. Even in same article provided by AFP, The result shows that some media stick to use the name Sea of Japan solely, and others demonstrate a will to use both name East Sea and Sea of Japan simultaneously. This study was able to show that the diffusion and spread of the place name was significantly influenced by social, political interests and powers, the mess geopolitics in pop cultural materials.

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Photorealism Effect of 3D Technical Realization - With an Emphasis on Image Reproduction of (3D 기술구현에서의 포토리얼리즘 효과 - 겨울왕국의 이미지 재현성을 중심으로)

  • Park, Kyung Mi;Yang, Jong Hoon
    • Cartoon and Animation Studies
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    • s.36
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    • pp.259-280
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    • 2014
  • Animation is showing the highest record in entertainment around the world and writing the history of 3D animation again. The image contents effect thanks to the proper introduction of the state-of-art digital technology, which is one of the causes of the outstanding entertainment and the factual reproduction of the images, provided an opportunity to transmit the meaning of image aesthetics, which is a virtual reality and image reproduction through the reality realization of photo medium, and to reinterpret the boundary of virtual reality. Especially, the development of digital contents technology due to scientific technologies demolishes the boundary of virtual reality and reality and creates the effect of making viewers be absorbed by realizing the virtual reality by means of 3D reality images which highlight the special characteristic of photos. The aspect of the contents technology and image aesthetics which can be interpreted in a view point beyond the existing concept of reality is found in the aura theory of Benjamin and in the Simulacres of Baudrillard. The 3D image by photo-reality herein presents various suggestions in the aspect of real existence of spatial expression, the meaning creation process of reality, the existence value of virtual images.

Application of an Automated Time Domain Reflectometry to Solute Transport Study at Field Scale: Experimental Methodology and Calibration of TDR (시간영역 광전자파 분석기(Automatic TDR System)를 이용한 오염물질의 거동에 관한 연구: 실험방법 및 검정)

  • Kim, Dong-Ju
    • Economic and Environmental Geology
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    • v.29 no.6
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    • pp.699-712
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    • 1996
  • Field scale experiments using an automated 144-channel TDR system were conducted which monitored the movement of solute through unsaturated loamy soils. The experiments were carried out on two different field plots of 0.54 ha to study the vertical movement of solute plume created by applying a square pulse of $CaCl_2$ as a tracer. The residence concentration was monitored at 24 locations on a transect and 5 depths per location by horizontally-positioning 50 cm long triple wire TDR probes to study the heterogeneity of solute travel times and the governing transport concept at field scale. This paper describes details of experimental methodology and calibration aspects of the TDR system. Three different calibration methods for estimation of solute concentration from TDR-measured bulk soil electrical conductivity were used for each field site. Data analysis of mean breakthrough curves (BTCs) and parameters estimated using the convection-dispersion model (CDE) and the convective-lognormal transfer function model (CLT) reveals that the automated TDR system is a viable technique to study the field scale solute transport providing a normal distribution of resident concentration in a high resolution of time series, and that calibration method does not significantly affect both the shape of BTC and the parameters related to the peak travel time. Among the calibration methods, the simple linear model (SLM), a modified version of Rhoades' model, appears to be promising in the calibration of horizontally-positioned TDR probes at field condition.

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