• Title/Summary/Keyword: Ordering scheme

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Optimal Parameters Estimation of Diffusion-Analogy Geomorphologic Instantaneous Unit Hydrograph Model (확산-유추 지형학적 순간단위도 모형의 최적매개변수 추정)

  • Kim, Joo-Cheol;Choi, Yong-Joon
    • Journal of Wetlands Research
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    • v.13 no.3
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    • pp.385-394
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    • 2011
  • In this study, optimal parameters of diffusion-analogy GIUH were calculated by separating channel and hillslope from drainage structures in the basin. Parameters of the model were composed of channel and hillslope, each velocity($u_c$, $u_h$) and diffusion coefficient($D_c$, $D_h$). Tanbu subwatershed in Bocheong river basin as a target basin was classified as 4th rivers by Strahler's ordering scheme. The optimization technique was applied to the SCE-UA, the estimated optimal parameters are as follows. $u_c$ : 0.589 m/s, $u_h$ : 0.021 m/s, $D_c$ : $34.469m^2/s$, $D_h$ : $0.1333m^2/s$. As a verification for the estimated parameters, the error of average peak flow was about 11 % and the error of peaktime was 0.3 hr. By examining the variability of parameters, the channel diffusion coefficient didn't have significant effect on hydrological response function. by considering these results, the model is expected to be simplified in the future.

The Geometric Properties of the Drainage Structures based on Fractal Tree (Fractal 나무를 기반으로 한 배수구조의 기하학적 특성)

  • Kim, Joo-Cheol;Kim, Jae-Han
    • Journal of Korea Water Resources Association
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    • v.41 no.8
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    • pp.797-806
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    • 2008
  • The geometric properties of the drainage structures are analyzed through depicting the drainage network which is composed of the whole drainage paths in the natural basin defined at the specific scale. The theoretical consideration is performed on the general structures of networks organized by ramification process based on Fractal tree and Horton's law. The drainage network is generated via ArcGIS, ordered by Strahler's ordering scheme and investigated with Strahler's order. As a results of the Richardson's method it is shown that there may exist the distinct behavioral characteristics between overland-flow and channel flow and the natural stream networks would be space-filling Fractals. As a result, it is shown that the values estimated by considering the overland-flow on being applied to the field data give the different results from the empirical method applied until now. As expected, therefore the results obtained from this study are sure to be devoted further researches on the channel networks.

A Study on the Improvement of Multitree Pattern Recognition Algorithm (Multitree 형상 인식 기법의 성능 개선에 관한 연구)

  • 김태성;이정희;김성대
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.14 no.4
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    • pp.348-359
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    • 1989
  • The multitree pattern recognition algorithm proposed by [1] and [2] is modified in order to improve its performance. The basic idea of the multitree pattern classification algorithm is that the binary dceision tree used to classify an unknow pattern is constructed for each feature and that at each stage, classification rule decides whether to classify the unknown pattern or to extract the feature value according to the feature ordet. So the feature ordering needed in the calssification procedure is simple and the number of features used in the classification procedure is small compared with other classification algorithms. Thus the algorithm can be easily applied to real pattern recognition problems even when the number of features and that of the classes are very large. In this paper, the wighting factor assignment scheme in the decision procedure is modified and various classification rules are proposed by means of the weighting factor. And the branch and bound method is applied to feature subset selection and feature ordering. Several experimental results show that the performance of the multitree pattern classification algorithm is improved by the proposed scheme.

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Performance Analysis of the Optimal Turbo Coded V-BLAST technique in Adaptive Modulation System (적응 변조 시스템에서 최적의 터보 부호화된 V-BLAST 기법의 성능 분석)

  • Lee, Kyung-Hwan;Choi, Kwang-Wook;Ryoo, Sang-Jin;Kang, Min-Goo;Hong, Dae-Ki;You, Cheol-Woo;Hwang, In-Tae;Kim, Cheol-Sung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.2
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    • pp.385-391
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    • 2007
  • In this paper, we propose and observe the Adaptive Modulation system with optimal Turbo Coded V-BLAST (Vertical-Bell-lab Layered Space-Time) technique that is applied the extrinsic information from MAP (Maximum A Posteriori) Decoder with Iterative Decoding to use as a priori probability in two decoding procedures of V-BLAST: ordering and slicing. Also, comparing with the Adaptive Modulation system using conventional Turbo Coded V-BLAST technique that is simply combined V-BLAST with Turbo Coding scheme, we observe how much throughput performance has been improved. As a result of simulation, in the Adaptive Modulation systems with several Turbo Coded V-BLAST techniques, the optimal Turbo Coded V-BLAST technique has higher throughput gain than the conventional Turbo Coded V-BLAST technique. Especially, the results show that the proposed scheme achieves the gain of 1.5 dB SNR compared to the conventional system at 2.5 Mbps throughput.

Experimental Optimal Choice Of Initial Candidate Inliers Of The Feature Pairs With Well-Ordering Property For The Sample Consensus Method In The Stitching Of Drone-based Aerial Images

  • Shin, Byeong-Chun;Seo, Jeong-Kweon
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.4
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    • pp.1648-1672
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    • 2020
  • There are several types of image registration in the sense of stitching separated images that overlap each other. One of these is feature-based registration by a common feature descriptor. In this study, we generate a mosaic of images using feature-based registration for drone aerial images. As a feature descriptor, we apply the scale-invariant feature transform descriptor. In order to investigate the authenticity of the feature points and to have the mapping function, we employ the sample consensus method; we consider the sensed image's inherent characteristic such as the geometric congruence between the feature points of the images to propose a novel hypothesis estimation of the mapping function of the stitching via some optimally chosen initial candidate inliers in the sample consensus method. Based on the experimental results, we show the efficiency of the proposed method compared with benchmark methodologies of random sampling consensus method (RANSAC); the well-ordering property defined in the context and the extensive stitching examples have supported the utility. Moreover, the sample consensus scheme proposed in this study is uncomplicated and robust, and some fatal miss stitching by RANSAC is remarkably reduced in the measure of the pixel difference.

Error Resilient Performance Evaluation of MPEG-4 and H.264/AVC (MPEG-4 와 H.264/AVC의 에러 강인 기술 성능 평가)

  • 정봉수;황영휘;전병우;김명돈;최송인
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.5
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    • pp.203-216
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    • 2004
  • Recent advances in video coding technology have resulted in rapid growth of application in mobile communication, With this explosive growth reliable transmission and error resilient technique become increasingly necessary to offer high quality multimedia service. In this paper, we present the result of our investigation on the error resilient performance evaluation of the MPEG-4 simple profile under the H.324/M and the H.264/AVC baseline under the IP packet networks. Especially, we have tested error resilient tools of MPEG-4 simple profile such as resynchronization marker insertion, data partitioning, and of H.264/AVC baseline such as the flexible macroblock ordering (FMO) scheme. The objective quality of decoded video is measured in terms of rate and PSNR under various random bit and burst error conditions.

A International Comparative Study on the Bidding System & Policy for the Public IT Project (공공 IT 프로젝트 수발주 제도와 정책의 국제간 비고)

  • Noh, Kyoo-Sung
    • Journal of Digital Convergence
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    • v.6 no.1
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    • pp.11-19
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    • 2008
  • The Bidding System of the public IT project in Korea is fallen behind, because of the ordering habitual practice based old system, overcompetition based sealed bid and subcontract practice. To innovate this old-fashioned practice for public IT project bidding, this paper wants to generate a proper improvement direction of the public IT project contract law and the related policy through the literature review about the ordering and receiving system in Korea, the practical survey about bidding marketplace in Korea, and competition between bidding system and/or policy of major countries: USA, UK, France and Japan. As a result of practical survey, many problems of the current public IT project bidding system came out and improvement ideas toward future situation turned up. These outputs implicate that the current law and system related public IT project demands better improvement work for the future ubiquitous Korea. Therefore, this paper, to solve these problems about bidding systems and practice, propose the new public IT project contract law and the related policy, reflecting these improvement ideas by the practical survey and the literature review, and benchmarking points from bidding system of other countries.

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Search space pruning technique for optimization of decision diagrams (결정 다이어그램의 최적화를 위한 탐색공간 축소 기법)

  • Song, Moon-Bae;Dong, Gyun-Tak;Chang, Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.8
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    • pp.2113-2119
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    • 1998
  • The optimization problem of BDDs plays an improtant role in the area of logic synthesis and formal verification. Since the variable ordering has great impacts on the size and form of BDD, finding a good variable order is very important problem. In this paper, a new variable ordering scheme called incremental optimization algorithm is presented. The proposed algorithm reduces search space more than a half of that of the conventional sifting algorithm, and computing time has been greatly reduced withoug depreciating the performance. Moreover, the incremental optimization algorithm is very simple than other variable reordering algorithms including the sifting algorithm. The proposed algorithm has been implemented and the efficiency has been show using may benchmark circuits.

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An Analysis on the Color Characteristics for Improving Childhood Children's Learning Spaces and Furniture Design (유아의 학습공간 및 가구 디자인 개선을 위한 색채특성 분석)

  • Kim, Ja Kyung;Moon, Sun Wook
    • Journal of the Korea Furniture Society
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    • v.28 no.4
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    • pp.294-304
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    • 2017
  • The purpose of this study is to analyse and derive the color characteristics of childhood children's learning spaces and furniture for improving the color design of those and to present the direction of design and to build up the DB. The study covers products from domestic and overseas infant furniture manufacturers and 11 preschool learning rooms. The study method uses the collected furniture and spatial images to derive a palette of colors and compare color characteristics. The analysis results show that, the domestic infant furniture tend to use a variety of colors with pale tone or use consistent hard wood furniture according to the requirements of adult taste and marketability. Also, it attempts to create a very negative color scheme, but it looks like disorganized, and there is not much color design integrated with the architecture. Thus, color designs ensure that the ordering elements of the color scheme are clearly recognized by applying preferred color tones of childhood, like vivid and bright tone with high chroma and middle or hight Brightness value. Lastly, it should establish guidelines for specific palettes and color scheme, which can be utilized in the design of childhood children's learning spaces and furniture.

Low Complexity MMSE with Successive Interference Cancellation for OFDM Systems over Time-selective Channels (시변 채널 환경에서 OFDM 시스템을 위한 복잡도가 감소된 MMSE-SIC 등화기법)

  • Park, Ji-Hyun;Hwang, Seung-Hoon;Whang, Keum-Chan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.7A
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    • pp.743-750
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    • 2008
  • Orthogonal frequency division multiplexing (OFDM) is a attractive modulation scheme for high data rate transmission in frequency-selective channels. However, the time selectivity of wireless channel introduces intercarrier interference (ICI), and consequently degrades system performance. In this paper, we first propose a novel recursive algorithm for minimum mean squared error (MMSE) with successive interference cancellation (SIC). The proposed algorithm can significantly reduce the complexity of the MMSE-SIC scheme and achieve the same performance when optimal ordering is known. Also, the further reduced scheme of the proposed algorithm can be developed based on ICI properties, while preserving performance.