• 제목/요약/키워드: reference for selection

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Fast Multiple Reference Frame Selection for H.264 Encoding (H.264 부호화를 위한 고속 다중 참조 화면 결정 기법)

  • Jeong, Jin-Woo;Cheo, Yoon-Sik
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.419-420
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    • 2006
  • In the new video coding standard H.264/AVC, motion estimation (ME) is allowed to search multiple reference frames for improve the rate-distortion performance. The complexity of multi-frame motion estimation increases linearly with the number of used reference frame. However, the distortion gain given by each reference frame varies with the video sequence, and it is not efficient to search through all the candidate frames. In this paper, we propose a fast mult-frame selection method using all zero coefficient block (AZCB) prediction and sum of difference (SAD) of neighbor block. Simulation results show that the speed of the proposed algorithm is up to two times faster than exhaustive search of multiple reference frames with similar quality and bit-rate.

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Fast and Accurate Visual Place Recognition Using Street-View Images

  • Lee, Keundong;Lee, Seungjae;Jung, Won Jo;Kim, Kee Tae
    • ETRI Journal
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    • v.39 no.1
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    • pp.97-107
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    • 2017
  • A fast and accurate building-level visual place recognition method built on an image-retrieval scheme using street-view images is proposed. Reference images generated from street-view images usually depict multiple buildings and confusing regions, such as roads, sky, and vehicles, which degrades retrieval accuracy and causes matching ambiguity. The proposed practical database refinement method uses informative reference image and keypoint selection. For database refinement, the method uses a spatial layout of the buildings in the reference image, specifically a building-identification mask image, which is obtained from a prebuilt three-dimensional model of the site. A global-positioning-system-aware retrieval structure is incorporated in it. To evaluate the method, we constructed a dataset over an area of $0.26km^2$. It was comprised of 38,700 reference images and corresponding building-identification mask images. The proposed method removed 25% of the database images using informative reference image selection. It achieved 85.6% recall of the top five candidates in 1.25 s of full processing. The method thus achieved high accuracy at a low computational complexity.

Fast Reference Frame Selection Method Based on Best Reference Frame Index Correlation

  • Kim, Hyungwook;Lim, Sojeong;Yu, Sungwook
    • ETRI Journal
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    • v.36 no.1
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    • pp.179-182
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    • 2014
  • This letter presents a very simple yet very effective solution for fast reference frame (RF) selection in H.264/AVC. By efficiently making use of the correlation between the best RF indices in various inter modes, the proposed method significantly reduces the number of RFs to be examined at the expense of a very small miss rate. Simulation results show that the proposed method not only improves upon the coding performance of conventional methods but also reduces the encoding time significantly.

A Study on the Records Management Reference Table of Environmental Authorities from the Perspective of Appraisal and Selection of National Archives (국가기록평가의 관점에서 본 환경 분야 기록관리기준표 분석)

  • Hyun, Moonsoo
    • The Korean Journal of Archival Studies
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    • no.67
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    • pp.139-203
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    • 2021
  • The study aims to analyze the records management reference tables currently being utilized and to provide directions on how should be redesigned in the future to operate as a appraisal tool for national archives. From the perspective of "what records should be the national archives", it was intended to analyze the records management reference tables, particularly in the environmental public authorities, and to propose future improvements. The main focus of the analysis is on appraising records that need to be preserved as national archives, and therefore, prior to analysis of the tables, it examines whether the archival selection criteria are clearly presented. Subsequently, the study is conducted how to implement this criteria through the records management reference table of each agency and how its implementation system will be constructed. The analysis will be focused on Ministry of Environment's records management reference table and records schedules or appraisal/selection tools of the central and federal institutions that perform environmental functions in U.S., Australia, and UK.

Selection and evaluation of reference genes for gene expression using quantitative real-time PCR in Mythimna separata walker (Lepidoptera: Noctuidae)

  • ZHANG, Bai-Zhong;LIU, Jun-Jie;CHEN, Xi-Ling;YUAN, Guo-Hui
    • Entomological Research
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    • v.48 no.5
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    • pp.390-399
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    • 2018
  • In order to precisely assess gene expression levels, the suitable internal reference genes must be served to quantify real-time reverse transcription polymerase chain reaction (RT-qPCR) data. For armyworm, Mythimna separata, which reference genes are suitable for assessing the level of transcriptional expression of target genes have yet to be explored. In this study, eight common reference genes, including ${\beta}$-actin (${\beta}$-ACT), 18 s ribosomal (18S), 28S ribosomal (28S), glyceraldehyde-3-phosphate (GAPDH), elongation fator-alpha ($EF1{\alpha}$), TATA box binding protein (TBP), ribosomal protein L7 (RPL7), and alpha-tubulin (${\alpha}$-TUB) that in different developmental stages, tissues and insecticide treatments of M. separata were evaluated. To further explore whether these genes were suitable to serve as endogenous controls, three software-based approaches (geNorm, BestKeeper, and NormFinder), the delta Ct method, and one web-based comprehensive tool (RefFinder) were employed to analyze and rank the tested genes. The optimal number of reference genes was determined using the geNorm program, and the suitability of particular reference genes was empirically validated according to normalized HSP70, and MsepCYP321A10 gene expression data. We found that the most suitable reference genes for the different experimental conditions. For developmental stages, 28S/RPL7 were the optimal reference genes, both $RPL7/EF1{\alpha}$ were suitable for experiments of different tissues, whereas for insecticide treatments, $28S/{\alpha}-TUB$ were suitable for normalizations of expression data. In addition, $28S/{\alpha}-TUB$ were the suitable reference genes because they have the most stable expression among different developmental stages, tissues and insecticide treatments. Our work is the first report on reference gene selection in M. separata, and might serve as a precedent for future gene expression studies.

Improvement Target SW Process Selection for Small and Medium Size Software Organizations (중소 소프트웨어 기업의 개선 대상 SW 프로세스 선정)

  • Lee, Yang-Kyu;Kim, Jong-Woo;Kwon, Won-Il;Jung, Chang-Sin;Bae, Se-Jin
    • The KIPS Transactions:PartD
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    • v.9D no.5
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    • pp.887-896
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    • 2002
  • Based on SPICE (Software Process Improvement and Capability dEtermination) evaluation model, SPIRE (Software Process Improvement in Regions of Europe) is developed and published as a process improvement model for small and medium size organizations. However, practical selection guidelines or mapping rules between business goals and software processes do not exist within SPIRE. This research aims to construct an objective reference mapping table between business goals and software processes, and to propose a process selection method using the mapping table. The mapping table is constructed by the convergence of domestic software process experts' opinions using Delphi techniques. In the suggested process selection method, target processes are selected using the intuition of project participants or project managers as well as the reference mapping table. The feasibility of the proposed selection method has been reviewed by applying to two small software companies. Using the reference mapping table, we could select key processes which were passed over by project managers.

Bayesian Model Selection for Inverse Gaussian Populations with Heterogeneity

  • Kang, Sang-Gil;Kim, Dal-Ho;Lee, Woo-Dong
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.2
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    • pp.621-634
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    • 2008
  • This paper addresses the problem of testing whether the means in several inverse Gaussian populations with heterogeneity are equal. The analysis of reciprocals for the equality of inverse Gaussian means needs the assumption of equal scale parameters. We propose Bayesian model selection procedures for testing equality of the inverse Gaussian means under the noninformative prior without the assumption of equal scale parameters. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. So we propose the objective Bayesian model selection procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Simulation study and real data analysis are provided.

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Fuzzy Logic Based Temporal Error Concealment for H.264 Video

  • Lee, Pei-Jun;Lin, Ming-Long
    • ETRI Journal
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    • v.28 no.5
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    • pp.574-582
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    • 2006
  • In this paper, a new error concealment algorithm is proposed for the H.264 standard. The algorithm consists of two processes. The first process uses a fuzzy logic method to select the size type of lost blocks. The motion vector of a lost block is calculated from the current frame, if the motion vectors of the neighboring blocks surrounding the lost block are discontinuous. Otherwise, the size type of the lost block can be determined from the preceding frame. The second process is an error concealment algorithm via a proposed adapted multiple-reference-frames selection for finding the lost motion vector. The adapted multiple-reference-frames selection is based on the motion estimation analysis of H.264 coding so that the number of searched frames can be reduced. Therefore the most accurate mode of the lost block can be determined with much less computation time in the selection of the lost motion vector. Experimental results show that the proposed algorithm achieves from 0.5 to 4.52 dB improvement when compared to the method in VM 9.0.

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Observer-based Feedback Controller Design for Robust Tracking of Discrete-time Polytopic Uncertain LTI Systems

  • Oh, Sangrok;Kim, Jung-Su;Shim, Hyungbo
    • Journal of Electrical Engineering and Technology
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    • v.10 no.6
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    • pp.2427-2433
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    • 2015
  • This paper presents an observer-based robust controller for constant reference tracking of linear time invariant systems with polytopic model uncertainties. To this end, this paper not only designs a robust integral controller gain but also suggests how to determine the robust observer gain and the observer model used in the observer. Since the observer model selection is not obvious due to the polytopic uncertainties, particular attention needs to be paid to that. This paper computes the robust controller and observer gains first. Then, the observer model is selected in a way that the whole closedloop is stable and LMIs are used in the middle of choosing the gains and observer model. Simulation examples show that the proposed observer-based feedback control successfully achieves robust reference tracking.

A Study on the Serials Evaluation Based on the Reference Analysis of SCI Articles (SCI 논문의 참고문헌 분석을 통한 학술지 평가에 관한 연구)

  • Choi, Kwi-Suk;Hwang, Nam-Gu
    • Journal of Information Management
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    • v.33 no.2
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    • pp.33-48
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    • 2002
  • This paper describes evaluation methods of serials and also introduces a case study related to the selection and evaluation of serials. A total of 1,291 titles of serials, which were subscription titles of POSTECH in the field of science and technology in 2002, were analyzed. This study employs the analysis of POSTECH SCI Article reference data to suggest the models for evaluating serials and to identify the guideline for journal selection and collection development.