• Title/Summary/Keyword: reference for selection

Search Result 518, Processing Time 0.027 seconds

Disparity-based Error Concealment for Stereoscopic Images with Superpixel Segmentation

  • Zhang, Yizhang;Tang, Guijin;Liu, Xiaohua;Sun, Changming
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.9
    • /
    • pp.4375-4388
    • /
    • 2018
  • To solve the problem of transmission errors in stereoscopic images, this paper proposes a novel error concealment (EC) method using superpixel segmentation and adaptive disparity selection (SSADS). Our algorithm consists of two steps. The first step is disparity estimation for each pixel in a reference image. In this step, the numbers of superpixel segmentation labels of stereoscopic images are used as a new constraint for disparity matching to reduce the effect of mismatching. The second step is disparity selection for a lost block. In this step, a strategy based on boundary smoothness is proposed to adaptively select the optimal disparity which is used for error concealment. Experimental results demonstrate that compared with other methods, the proposed method has significant advantages in both objective and subjective quality assessment.

Extrema-based Band Selection for Hyperion Data (극단화소 기반의 Hyperion 데이터 밴드선택)

  • Han Dong-Yeop;Kim Dae-Sung;Kim Yong-Il
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2006.04a
    • /
    • pp.193-198
    • /
    • 2006
  • Among 242 Hyperion bands, there are 46 bands that contain completely no information and some other bands with various kinds of noise. It is mainly due to the atmosphenc absorption and the low signal-to-noise ratio. The visual inspection for selecting clean and stable bands is a simple practice, but is a manual, inefficient, and subjective Process. Though uncalibrated, overlapping, and all deep water absorption bands are removed, there still exist noisy bands. In this paper, we propose that the extrema ratio be measured for noise estimation and the unsupervised band selection be performed using the Expectation-Maximization algorithm. The Hyperion data were classified into 5 categories according to the image quality by visual inspection, and used as the reference data. The accuracy of the proposed method was compared with signal-to-noise ranking and entropy ranking. As a result, the proposed mettled was effective as preprocessing step for band selection.

  • PDF

A Study on the Development of Reference Criteria for Airport Selection in the Establishment of the Gadeok New Airport Corporation using Delphi Techniques (델파이기법을 이용한 가덕신공항 운영당국 설립시 참조공항 선정기준 도출에 관한 연구)

  • Kwangil Kim
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.32 no.2
    • /
    • pp.65-71
    • /
    • 2024
  • It is anticipated that Gadeok New Airport will be constructed, and the entity responsible for its operation will be a new airport authority, not the existing airport corporation, as the Ministry of Land, Infrastructure and Transport has announced its plan to establish the Gadeok New Airport Construction Authority. Based on the precedents of existing airport corporations, it is expected that the future authority will undergo organizational changes to become an airport corporation. This study seeks to establish criteria for selecting overseas airports for benchmarking when researching the entity that will operate the newly established Gadeok New Airport authority. To provide a specific basis for selecting overseas airports for the future operation of Gadeok Airport, the Delphi survey method will be used to derive criteria. Currently, when examining the participation of local governments in regional airports, Gimhae International Airport is operated solely by the Korea Airports Corporation, receiving criticism for the lack of participation by the local government, such as Busan City, in decision-making related to airport operation and local reinvestment. Therefore, it is deemed necessary to provide early direction for improvement in this regard.

Macroblock-based Adaptive Interpolation Filter Method Using New Filter Selection Criterion in H.264/AVC (H.264/AVC에서 새로운 필터 선택 기준을 이용한 매크로 블록 기반 적응 보간 필터 방법)

  • Yoon, Kun-Su;Moon, Yong-Ho;Kim, Jae-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.33 no.4C
    • /
    • pp.312-320
    • /
    • 2008
  • The macroblock-based adaptive interpolation filter method has been considered to be able to achieve high coding efficiency in H.264/AVC. In this method, although the filter selection criterion considered in terms of rate and distortion have showed a good performance, it still leaves room for improvement. To improve high coding efficiency better than conventional method, we propose a new filter selection criterion which considers two bit rates, motion vector and prediction error, and reconstruction error. In addition, the algorithm for reducing the overhead of transmitting the selected filter information is presented. Experimental results show that the proposed method significantly improves the coding efficiency compared to ones using conventional criterion. It leads to about a 5.19% (1 reference frame) and 5.14% (5 reference frames) bit rate savings on average compared to H.264/AVC, respectively.

Effects of Corpus Use on Error Identification in L2 Writing

  • Yoshiho Satake
    • Asia Pacific Journal of Corpus Research
    • /
    • v.4 no.1
    • /
    • pp.61-71
    • /
    • 2023
  • This study examines the effects of data-driven learning (DDL)-an approach employing corpora for inductive language pattern learning-on error identification in second language (L2) writing. The data consists of error identification instances from fifty-five participants, compared across different reference materials: the Corpus of Contemporary American English (COCA), dictionaries, and no use of reference materials. There are three significant findings. First, the use of COCA effectively identified collocational and form-related errors due to inductive inference drawn from multiple example sentences. Secondly, dictionaries were beneficial for identifying lexical errors, where providing meaning information was helpful. Finally, the participants often employed a strategic approach, identifying many simple errors without reference materials. However, while maximizing error identification, this strategy also led to mislabeling correct expressions as errors. The author has concluded that the strategic selection of reference materials can significantly enhance the effectiveness of error identification in L2 writing. The use of a corpus offers advantages such as easy access to target phrases and frequency information-features especially useful given that most errors were collocational and form-related. The findings suggest that teachers should guide learners to effectively use appropriate reference materials to identify errors based on error types.

Development of an Expert System for Rapid Prototyping Machine Selection (쾌속조형장비 선정을 위한 전문가시스템 개발)

  • 정일용;이일랑;최병욱
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2002.10a
    • /
    • pp.632-635
    • /
    • 2002
  • There are more than five dozen different RP(rapid prototyping) systems in the world and they are fairly expensive. All those systems have different capabilities and requirements in that each of them gives different tolerance, application field and part strength, etc. This situation may cause a problem of selecting an appropriate RP system. This paper presents an expert system, utilizing an algorithm that is composed up of rules to derive recommendations and answers to queries of the RP users. The expert system incorporates RP machines commercially available and adopts multi-selection criteria, namely, machine price, accuracy, build size, adopted process, etc. In the expert system, forward reasoning method is adopted and external spreadsheet for sub-data of the RP systems is used. The rules and knowledge are obtained from interviews and discussions with RP vendors and users, appropriate research publications and other reference materials.

  • PDF

Error-Resilient Video Transmission Techniques over Unreliable Networks (비 신뢰성 네트워크에서 에러를 극복하는 비디오 전송 기법)

  • 노경택
    • Journal of the Korea Society of Computer and Information
    • /
    • v.6 no.3
    • /
    • pp.50-55
    • /
    • 2001
  • We review error resilience techniques for real-time video transport over unreliable networks. For error control on the source coding level, each decoder has to make provisions for error detection, resynchronization. and error concealment. and we review techniques suitable for that purpose. Further, techniques are discussed for intelligent processing of acknowledgment information by the coding control to adapt the source coder to the channel. We review and compare error tracking, error confinement. and reference picture selection techniques for channel-adaptive source coding. We review how feedback-based source codings are related with the precompressed video stored on a media server

  • PDF

A Site Environment Analysis of NDGPS Reference Stations Co-operating for SBAS (NDGPS 기준국의 SBAS 기준국으로의 공동 활용을 위한 기준국 환경 분석)

  • Han, Young-hoon;Park, Sul-gee;Park, Sang-hyun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.9
    • /
    • pp.1696-1703
    • /
    • 2016
  • In this paper, it verifies site environment aspect that NDGPS (Nationwide Differential Global Positioning System) operated by MOF (Ministry of Oceans and Fisheries) will be used as the same site of reference stations for SBAS (Satellite Based Augmentation System). In order to prove this feasibility, we analyze the site environment requirements for SBAS reference stations, as well as we establish the procedure for the verification of the site environment requirements. With this procedure of the site environment survey, we perform site survey in the real field and analyze the results. We select interim candidate sites for survey which currently operating 17 NDGPS reference stations. This paper could be utilized in the process of selection or installation of reference stations in the field of GNSS(Global Navigation Satellite System) and the drawing the consideration which NDGPS reference stations will be co-operated as SBAS reference stations.

Evaluation of reference genes for RT-qPCR study in abalone Haliotis discus hannai during heavy metal overload stress

  • Lee, Sang Yoon;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
    • /
    • v.19 no.4
    • /
    • pp.21.1-21.11
    • /
    • 2016
  • Background: The evaluation of suitable reference genes as normalization controls is a prerequisite requirement for launching quantitative reverse transcription-PCR (RT-qPCR)-based expression study. In order to select the stable reference genes in abalone Haliotis discus hannai tissues (gill and hepatopancreas) under heavy metal exposure conditions (Cu, Zn, and Cd), 12 potential candidate housekeeping genes were subjected to expression stability based on the comprehensive ranking while integrating four different statistical algorithms (geNorm, NormFinder, BestKeeper, and ${\Delta}CT$ method). Results: Expression stability in the gill subset was determined as RPL7 > RPL8 > ACTB > RPL3 > PPIB > RPL7A > EF1A > RPL4 > GAPDH > RPL5 > UBE2 > B-TU. On the other hand, the ranking in the subset for hepatopancreas was RPL7 > RPL3 > RPL8 > ACTB > RPL4 > EF1A > RPL5 > RPL7A > B-TU > UBE2 > PPIB > GAPDH. The pairwise variation assessed by the geNorm program indicates that two reference genes could be sufficient for accurate normalization in both gill and hepatopancreas subsets. Overall, both gill and hepatopancreas subsets recommended ribosomal protein genes (particularly RPL7) as stable references, whereas traditional housekeepers such as ${\beta}-tubulin$ (B-TU) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were ranked as unstable genes. The validation of reference gene selection was confirmed with the quantitative assay of MT transcripts. Conclusions: The present analysis showed the importance of validating reference genes with multiple algorithmic approaches to select genes that are truly stable. Our results indicate that expression stability of a given reference gene could not always have consensus across tissue types. The data from this study could be a good guide for the future design of RT-qPCR studies with respect to metal regulation/detoxification and other related physiologies in this abalone species.

Comparison of genomic predictions for carcass and reproduction traits in Berkshire, Duroc and Yorkshire populations in Korea

  • Iqbal, Asif;Choi, Tae-Jeong;Kim, You-Sam;Lee, Yun-Mi;Alam, M. Zahangir;Jung, Jong-Hyun;Choe, Ho-Sung;Kim, Jong-Joo
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.11
    • /
    • pp.1657-1663
    • /
    • 2019
  • Objective: A genome-based best linear unbiased prediction (GBLUP) method was applied to evaluate accuracies of genomic estimated breeding value (GEBV) of carcass and reproductive traits in Berkshire, Duroc and Yorkshire populations in Korean swine breeding farms. Methods: The data comprised a total of 1,870, 696, and 1,723 genotyped pigs belonging to Berkshire, Duroc and Yorkshire breeds, respectively. Reference populations for carcass traits consisted of 888 Berkshire, 466 Duroc, and 1,208 Yorkshire pigs, and those for reproductive traits comprised 210, 154, and 890 dams for the respective breeds. The carcass traits analyzed were backfat thickness (BFT) and carcass weight (CWT), and the reproductive traits were total number born (TNB) and number born alive (NBA). For each trait, GEBV accuracies were evaluated with a GEBV BLUP model and realized GEBVs. Results: The accuracies under the GBLUP model for BFT and CWT ranged from 0.33-0.72 and 0.33-0.63, respectively. For NBA and TNB, the model accuracies ranged 0.32 to 0.54 and 0.39 to 0.56, respectively. The realized accuracy estimates for BFT and CWT ranged 0.30 to 0.46 and 0.09 to 0.27, respectively, and 0.50 to 0.70 and 0.70 to 0.87 for NBA and TNB, respectively. For the carcass traits, the GEBV accuracies under the GBLUP model were higher than the realized GEBV accuracies across the breed populations, while for reproductive traits the realized accuracies were higher than the model based GEBV accuracies. Conclusion: The genomic prediction accuracy increased with reference population size and heritability of the trait. The GEBV accuracies were also influenced by GEBV estimation method, such that careful selection of animals based on the estimated GEBVs is needed. GEBV accuracy will increase with a larger sized reference population, which would be more beneficial for traits with low heritability such as reproductive traits.