• Title/Summary/Keyword: Log-MAP

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Performance Improvement of the battening Effect of the new Asymmetric Turbo Codes (새로운 비대칭 구조를 갖는 터보부호의 Flattening Effect의 성능향상에 관한 연구)

  • 정대호;정성태;김환용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.6A
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    • pp.533-539
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    • 2002
  • It is well known the fact that turbo lodes has better performance as the number of iteration and the interleaver size increases in the AWGN channel environment. However, as the number of iteration and the interleaver size are increased, it is required much delay and computation for iterative decoding, and caused the flattening effect phenomenon which is very litter BER performance improvement at the arbitrary SNR. In this paper, We proposed the new asymmetric turbo codes, which consist of parallel concatenated turbo codes that use mixed types of component codes with different not only constraint length but also generate polynomial and analyzed its BER performance for log-MAP decoding algorithm with frame size of 128, 256, 512 and 1024 bits, and coding rate of 1/3. As a results of simulation, proposed asymmetric turbo codes verify that its BER performance is superior to conventional symmetric turbo codes. It can be also observed that the flattening effect phenomenon is very reduced by applying the proposed asymmetric turbo codes. It gains respectively 1.7dB ~2.5dB and 2.0dB~2.5dB SNR improvements in the case of short frame(128, 256) and large frame(512, 1024) size for the BER $10_{-4}$>/TEX> region.

An Illumination-Insensitive Stereo Matching Scheme Based on Weighted Mutual Information (조명 변화에 강인한 상호 정보량 기반 스테레오 정합 기법)

  • Heo, Yong Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.11
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    • pp.2271-2283
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    • 2015
  • In this paper, we propose a method which infers an accurate disparity map for radiometrically varying stereo images. For this end, firstly, we transform the input color images to the log-chromaticity color space from which a linear relationship can be established during constructing a joint pdf between input stereo images. Based on this linear property, we present a new stereo matching cost by combining weighted mutual information and the SIFT (Scale Invariant Feature Transform) descriptor with segment-based plane-fitting constraints to robustly find correspondences for stereo image pairs which undergo radiometric variations. Experimental results show that our method outperforms previous methods and produces accurate disparity maps even for stereo images with severe radiometric differences.

Decomposition of Sediment size Curves into Log-Normal components: An Example from Cheju Strait Continental shelf (퇴적물입도곡선의 정규성분으로의 분해:제주해협의 예)

  • 공영세;김원식
    • 한국해양학회지
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    • v.28 no.2
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    • pp.114-120
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    • 1993
  • Numerical method of nonlinear regression was introduced to characterize grain-size distribution more effectively than using the traditional textural parameters. This technique proved critical particularly to multimodal size distributions, as exemplified by samples from Cheju strait continental shelf. Grain-size analysis of samples collected from the Cheju Strait continental shelf reveals that 86% of the grain-size distributions are multimodal. As multimodal grain-size distribution deviates from the statistical (log) normal distribution, the grain-size parameters traditionally used in sediment studies do not describe the distribution efficiently. Therefore, the use of grain-size curves into elementary normal component curves was used. Means and standard deviations of 387 decomposed normal components were decided by a decomposition method (nonlinear least square regression) from 167 size curves of the Cheju Strait sediments. The mean values of decomposed normal components show peaks at 1-3 phi and 8-9 phi size classes. The plot of mean values of the coarse fraction normal components on the map shows a characteristic and complex areal distribution. On the basis of the areal distribution of the mean values of the components and that of isopach of total Plenipotence sediment, the areal distribution of layers composing a transgressive sand of Late Plenipotence age were revealed.

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Development of an Optimized Class Space and Map based on the Metaverse ZEP Platform (메타버스 ZEP 플랫폼 기반의 최적화된 수업 공간 및 맵 개발)

  • Ae-ran Park;Myung-suk Lee
    • Journal of Practical Engineering Education
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    • v.15 no.2
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    • pp.439 -447
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    • 2023
  • This paper aims to develop a map for optimized class space using ZEP among the metaverse platforms. As a research method, the classroom space was organized so that the subject of learning became a learner, and the classroom space was modified and supplemented to optimize while being applied to elementary school computer classes. The contents of the study investigated learners' prior perception of metaverse, and compared and analyzed the advantages and disadvantages of the metaverse platform. In addition, the map was designed by reflecting the results of the survey, and after applying the map to the class, necessary APIs and apps were installed to supplement it. As a result, the learner became the subject of learning in the metaverse space, freely identified the space, and actively participated in the class. In particular, we found that students who were passive offline and those who had a low participation rate due to lack of skills participated more actively. In particular, students who were passive offline or whose participation was low due to lack of skills participated more actively. If API and JavaScript programs are added to collect log data of learners for learning analysis, real-time feedback is possible for learners, and learner feedback is possible for instructors with statistical data. If this is possible, the metaverse space can fully expect the role of a learning assistant for learners and a teaching assistant for instructors.

SuperDepthTransfer: Depth Extraction from Image Using Instance-Based Learning with Superpixels

  • Zhu, Yuesheng;Jiang, Yifeng;Huang, Zhuandi;Luo, Guibo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.10
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    • pp.4968-4986
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    • 2017
  • In this paper, we primarily address the difficulty of automatic generation of a plausible depth map from a single image in an unstructured environment. The aim is to extrapolate a depth map with a more correct, rich, and distinct depth order, which is both quantitatively accurate as well as visually pleasing. Our technique, which is fundamentally based on a preexisting DepthTransfer algorithm, transfers depth information at the level of superpixels. This occurs within a framework that replaces a pixel basis with one of instance-based learning. A vital superpixels feature enhancing matching precision is posterior incorporation of predictive semantic labels into the depth extraction procedure. Finally, a modified Cross Bilateral Filter is leveraged to augment the final depth field. For training and evaluation, experiments were conducted using the Make3D Range Image Dataset and vividly demonstrate that this depth estimation method outperforms state-of-the-art methods for the correlation coefficient metric, mean log10 error and root mean squared error, and achieves comparable performance for the average relative error metric in both efficacy and computational efficiency. This approach can be utilized to automatically convert 2D images into stereo for 3D visualization, producing anaglyph images that are visually superior in realism and simultaneously more immersive.

Development of the Computer-assisted Nutrition Education Program of Eating-out Guidance for Teenagers (올바른 외식지도를 위한 청소년용 영양교육 사이트(Health14.net) 개발)

  • Bae, Eun-Young;Lee, Kyung-Hea;Lyu, Eun-Soon;Her, Eun-Sil
    • Korean Journal of Community Nutrition
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    • v.12 no.4
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    • pp.462-476
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    • 2007
  • This study aimed to develop a nutrition education internet program for correcting the eating-out behaviorial problems of youth. A survey was performed to investigate the eating-out behavior patterns of youth by questionnaires. A nutrition education program was developed on the basis of the survey results, and evaluated by teenagers. The results of the developed homepage are summarized as follows: The contents of this program (www.health14.net) consist of '${\times}$ Health (Teenager, My Health, Healthy life, Beautiful life)', '+ Nutrition (To find slow foods, Fast foods campaign, Selecting fast foods, The best menu for eating-out, Recipes for health, Golden bell nutrition quiz)', '${\div}$ Information (Diet mini-homepage, Q & A, My knowhow, Game, Community)' and 'Basic Menu (home, Log in, Information and news, Mini-homepage, Site map, Free bulletin board)'. It can be used as educational material for dietary behaviorial changes in school. Also teachers and parents could get information on eating-out menus. Through this site, we anticipate contributing to nutritional health promotion by correcting the eating-out habits of youth.

Estimation of Probability rainfall isohyetal map of Gyengbuk Province (경북지역의 확률강우량도 산정)

  • Park, Ki-Bum;Lee, Su-Hyung;Kim, Do-Hun;Lee, Hyo-Jin;Cha, Sang-Hwa
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.939-942
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    • 2009
  • 본 연구는 경북지역의 11개 관측소와 인근 9개의 관측소의 강우자료를 이용하여 경북지역에 한정된 확률강우량도를 작성하였다. 최근 행정구역별 치수계획의 수립이 빈번해지고 소규모 유역의 개발로 인한 홍수량 산정 등이 빈번해지고 있다. 그러나 대부분이 강우관측소가 유역내에 위치해 있지 않고 인접한 기상관측소의 자료를 이용하고 있는 실정이고, 공공기관이나 실무를 수행함에 있어 유역의 강우량 적용에 있어 소규모 유역의 강우량이 지점강우량에 의해 결정되므로 어느 정도의 편차를 보이는지 추정이 사실상 곤란하였다. 따라서 본 연구에서는 경북지역에 한정하여 지점강우량을 빈도해석하여 확률강우량도를 작성하여 강우관측소가 인접하지 않아도 소규모 유역의 확률강우량의 근사치를 추정하여 지점빈도해석과 비교할 수 있도록 확률강우량도를 작성하였다. 경북지역인근 강우관측소의 자료를 강우 분석하여 확률분포형을 선정한 결과 거창, 구미, 대구, 문경, 밀양, 봉화, 안동, 영덕, 영주, 울산, 의성, 제천 충주, 추풍령, 합천은 Gumbel 분포가 적합한 것으로 나타났으며, 보은은 2변수 Log-Gumbel 분포가 적합한 것으로 나타났으며, 영천, 울진, 태백은 Gamma 분포가 적합한 것으로 나타나고 포항은 GEV 분포가 적합한 것으로 나타났다.

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COMPOSITION OPERATORS ON THE PRIVALOV SPACES OF THE UNIT BALL OF ℂn

  • UEKI SEI-ICHIRO
    • Journal of the Korean Mathematical Society
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    • v.42 no.1
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    • pp.111-127
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    • 2005
  • Let B and S be the unit ball and the unit sphere in $\mathbb{C}^n$, respectively. Let ${\sigma}$ be the normalized Lebesgue measure on S. Define the Privalov spaces $N^P(B)\;(1\;<\;p\;<\;{\infty})$ by $$N^P(B)\;=\;\{\;f\;{\in}\;H(B) : \sup_{0 where H(B) is the space of all holomorphic functions in B. Let ${\varphi}$ be a holomorphic self-map of B. Let ${\mu}$ denote the pull-back measure ${\sigma}o({\varphi}^{\ast})^{-1}$. In this paper, we prove that the composition operator $C_{\varphi}$ is metrically bounded on $N^P$(B) if and only if ${\mu}(S(\zeta,\delta)){\le}C{\delta}^n$ for some constant C and $C_{\varphi}$ is metrically compact on $N^P(B)$ if and only if ${\mu}(S(\zeta,\delta))=o({\delta}^n)$ as ${\delta}\;{\downarrow}\;0$ uniformly in ${\zeta}\;\in\;S. Our results are an analogous results for Mac Cluer's Carleson-measure criterion for the boundedness or compactness of $C_{\varphi}$ on the Hardy spaces $H^P(B)$.

Simulation of 1983 Central East Sea Tsunami by Parallel FEM Model (병렬 FEM 모형을 이용한 1983년 동해 중부 지진해일 시뮬레이션)

  • Choi Byung-Ho;Pelinovsky Efim;Hong Sung-Jin
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.18 no.1
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    • pp.21-34
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    • 2006
  • The simulation of tsunami inundation using detailed bathymetry and topography is required to establish the countermeasure of disaster mitigation and the tsunami hazard map. In this study, a simulation of the 1983 tsunami event in the East Sea using parallel finite element model, which is possible to simulate with suitable accuracy by the Beowulf parallel computation method, is performed to produce detailed features of coastal inundation. Results of simulations are compared with measured data. The evolution of statistic distribution of tsunami heights is studied numerically and the distribution functions of tsunami heights show a tendency to the log-normal curve along coastal area.

Simulation of 1993 East Sea Tsunami by Parallel FEM Model (병렬 FEM 모형을 이용한 1993년 동해 지진해일 시뮬레이션)

  • Hong, Sung-Jin;Choi, Byung-Ho;Pelinovsky, Efim
    • Journal of the Earthquake Engineering Society of Korea
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    • v.10 no.3 s.49
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    • pp.35-45
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    • 2006
  • The simulation of tsunami using detailed bathymetry and topography is required to establish the countermeasure of disaster mitigation and the tsunami hazard map. In this study, a simulation of the 1993 tsunami event in the East Sea using parallel finite element model, which is possible to simulate with suitable accuracy by the Beowulf parallel computation method, is performed to produce detailed features of coastal inundation. Results of simulation are compared with measured data. The evolution of statistic distribution of tsunami heights is studied numerically and the distribution functions of tsunami heights show a tendency to the log-normal curve along coastal area.