• Title/Summary/Keyword: Robust Estimation

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Evaluation of the Degrees of Genetic Connectedness Among Duroc Breed Herds (국내 두록종 농장간 유전적 연결성 추정)

  • Cho, Chungil;Choi, Jaekwan;Park, Byoungho;Kim, Sidong;Kwon, Ohsub;Choi, Youlim;Choy, Yunho
    • Journal of Animal Science and Technology
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    • v.54 no.5
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    • pp.337-340
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    • 2012
  • The genetic connectedness between herds is an essential requirement to make robust across-herd estimation of the breeding values of the animals. In this study, genetic connectedness between herds was evaluated by a connectedness rating method. A total of 24,971 records of days to 90 kg (D90KG) of the pigs on performance testing programs collected from six herds (labeled from 'A' to 'F') of Duroc breed along with pedigree information comprising 456,697 families were used. Results showed that a total of eight boars were used for semen exchange programs among participant farms. Herds 'A' through 'E' were found strongly connected among them. But 'F' herd was genetically connected strongly only with 'A' herd. The highest average connectedness rating was 91.7% between 'A' herd and 'C' herd. The lowest average connectedness rating was 65.1% between 'D' and 'F'. The concept of a single genetic group comprising six Duroc herds studied is meaningful due to high connectedness rates among them. Therefore, with this high genetic ties between participant Duroc farms, the more accurate genetic evaluation would be possible.

Development of technology in estimating of high-risk driver's behavior (고위험군 운전자의 운행행태 판단기술 개발)

  • Jin, Ju-Hyun;Yoo, Bong-Seok;Lee, Wook-Soo;Kim, Gyu-Ho
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.5
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    • pp.531-538
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    • 2016
  • Driving behaviors such as speeding and illegal u-turn which violate traffic rules are main causes of car accidents, and they can lead to serious accidents. Bus drivers are less aware of dangers of illegal u-turn, and infrastructures such as traffic enforcement equipment and watchmen are deficient. This research aims to develop technology for estimating driving behaviors based on map-matching in order to prevent illegal u-turns. For this research, 23,782 of u-turn permit data and 146,000 of speed limit data are collected nationwide, and an estimation algorithm is built with these data. Then, an application based on android is developed, and finally, tests are conducted to assess the accuracy in data computations and GPS data map-matching, and to extrapolate driving behavior. As a result of the tests, the accuracy results in the map-matching is 86% and the assessment of driving behavior is 83%, while the display of the data output yielded 100% accuracy. Additional research should focus on improvement in accuracy through the development of a robust monitoring system, and study of service scenarios for technology application.

Estimation of the relationship between below-ground root and above-ground canopy development by measuring dynamic change of soil ammonium-N concentration in rice

  • Fushimi, Erina;Yoshida, Hiroe;Tokida, Takeshi;Nakagawa, Hiroshi
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.183-183
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    • 2017
  • In the early part of rice growth, root volume primarily limits the amount of plant-accessible nitrogen (N). Therefore, knowledge of the root development is important for modeling N uptake of rice. The timing when the volume of rhizosphere cover the whole soil is also important to carry out timely top dressing. However, information about initial root expansion and associated N uptake is limited due to intrinsic technical difficulties in assessing below-ground processes. Some studies, however, showed a close relationship between below-ground root and above-ground leaf development, suggesting a possibility that above-ground attributes could serve as surrogates for the root processes. In this study, we investigated the relationship between below-ground and above-ground development of rice. Field experiments were conducted where we cultivated Koshihikari (a leading cultivar in Japan) for four different cropping schedules in 2012. In 2016, Gimbozu (HEG4) and three flowering time mutant lines of Gimbozu (X61 (se13), HS276 (ef7), DMG9 (se13, ef7)) were examined for a single season. Experiments were performed with three replications in a completely randomized design. We monitored ammonium-N concentration ([NH4+-N]) in soil solution by repeatedly taking samples from a porous tubing (10-cm long) vertically inserted at the most distant point from surrounding rice hills. Samples were taken in triplicate (= triplicate tubes) and every three days from transplanting in each experimental unit. For above-ground attributes, leaf area index (LAI) was measured in 2012, whereas soil coverage ratio was estimated by image processing in 2016. Results showed that [NH4+-N] increased gradually after transplanting and then rapidly decreased from a certain day. This distinct drop in [NH4+-N] informed us the timing at which the rice root system reached the point of porous tubing and thus essentially covered the whole soil volume. The LAI at the dropping point was about 0.43 regardless of the cropping schedules in 2012 experiment. In 2016, the coverage ratio at the N dropping point was within the range of 0.12 to 0.19 for four genotypes having different growth durations. In addition, the coverage ratios at seven weeks after the transplanting showed a good correspondence to LAI across the four genotypes. We therefore conclude that both LAI and coverage ratio may serve as robust indicators for root development and might be useful to estimate the timing when the root system fully cover the soil volume. Results obtained here will also contribute to develop models that can predict not only above-ground canopy development but also associated below-ground processes.

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A Fast Error Concealment Using a Data Hiding Technique and a Robust Error Resilience for Video (데이터 숨김과 오류 내성 기법을 이용한 빠른 비디오 오류 은닉)

  • Kim, Jin-Ok
    • The KIPS Transactions:PartB
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    • v.10B no.2
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    • pp.143-150
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    • 2003
  • Error concealment plays an important role in combating transmission errors. Methods of error concealment which produce better quality are generally of higher complexity, thus making some of the more sophisticated algorithms is not suitable for real-time applications. In this paper, we develop temporal and spatial error resilient video encoding and data hiding approach to facilitate the error concealment at the decoder. Block interleaving scheme is introduced to isolate erroneous blocks caused by packet losses for spatial area of error resilience. For temporal area of error resilience, data hiding is applied to the transmission of parity bits to protect motion vectors. To do error concealment quickly, a set of edge features extracted from a block is embedded imperceptibly using data hiding into the host media and transmitted to decoder. If some part of the media data is damaged during transmission, the embedded features are used for concealment of lost data at decoder. This method decreases a complexity of error concealment by reducing the estimation process of lost data from neighbor blocks. The proposed data hiding method of parity bits and block features is not influence much to the complexity of standard encoder. Experimental results show that proposed method conceals properly and effectively burst errors occurred on transmission channel like Internet.

A Bayesian Approach to Gumbel Mixture Distribution for the Estimation of Parameter and its use to the Rainfall Frequency Analysis (Bayesian 기법을 이용한 혼합 Gumbel 분포 매개변수 추정 및 강우빈도해석 기법 개발)

  • Choi, Hong-Geun;Uranchimeg, Sumiya;Kim, Yong-Tak;Kwon, Hyun-Han
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.38 no.2
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    • pp.249-259
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    • 2018
  • More than half of annual rainfall occurs in summer season in Korea due to its climate condition and geographical location. A frequency analysis is mostly adopted for designing hydraulic structure under the such concentrated rainfall condition. Among the various distributions, univariate Gumbel distribution has been routinely used for rainfall frequency analysis in Korea. However, the distributional changes in extreme rainfall have been globally observed including Korea. More specifically, the univariate Gumbel distribution based rainfall frequency analysis is often fail to describe multimodal behaviors which are mainly influenced by distinct climate conditions during the wet season. In this context, we purposed a Gumbel mixture distribution based rainfall frequency analysis with a Bayesian framework, and further the results were compared to that of the univariate. It was found that the proposed model showed better performance in describing underlying distributions, leading to the lower Bayesian information criterion (BIC) values. The mixed Gumbel distribution was more robust for describing the upper tail of the distribution which playes a crucial role in estimating more reliable estimates of design rainfall uncertainty occurred by peak of upper tail than single Gumbel distribution. Therefore, it can be concluded that the mixed Gumbel distribution is more compatible for extreme frequency analysis rainfall data with two or more peaks on its distribution.

Detection Method for Bean Cotyledon Locations under Vinyl Mulch Using Multiple Infrared Sensors

  • Lee, Kyou-Seung;Cho, Yong-jin;Lee, Dong-Hoon
    • Journal of Biosystems Engineering
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    • v.41 no.3
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    • pp.263-272
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    • 2016
  • Purpose: Pulse crop damage due to wild birds is a serious problem, to the extent that the rate of damage during the period of time between seeding and the stage of cotyledon reaches 45.4% on average. This study investigated a method of fundamentally blocking birds from eating crops by conducting vinyl mulching after seeding and identifying the growing locations for beans to perform punching. Methods: Infrared (IR) sensors that could measure the temperature without contact were used to recognize the locations of soybean cotyledons below vinyl mulch. To expand the measurable range, 10 IR sensors were arranged in a linear array. A sliding mechanical device was used to reconstruct the two-dimensional spatial variance information of targets. Spatial interpolation was applied to the two-dimensional temperature distribution information measured in real time to improve the resolution of the bean coleoptile locations. The temperature distributions above the vinyl mulch for five species of soybeans over a period of six days from the appearance of the cotyledon stage were analyzed. Results: During the experimental period, cases where bean cotyledons did and did not come into contact with the bottom of the vinyl mulch were both observed, and depended on the degree of growth of the bean cotyledons. Although the locations of bean cotyledons could be estimated through temperature distribution analyses in cases where they came into contact with the bottom of the vinyl mulch, this estimation showed somewhat large errors according to the time that had passed after the cotyledon stage. The detection results were similar for similar types of crops. Thus, this method could be applied to crops with similar growth patterns. According to the results of 360 experiments that were conducted (five species of bean ${\times}$ six days ${\times}$ four speed levels ${\times}$ three repetitions), the location detection performance had an accuracy of 36.9%, and the range of location errors was 0-4.9 cm (RMSE = 3.1 cm). During a period of 3-5 days after the cotyledon stage, the location detection performance had an accuracy of 59% (RMSE = 3.9 cm). Conclusions: In the present study, to fundamentally solve the problem of damage to beans from birds in the early stage after seeding, a working method was proposed in which punching is carried out after seeding, thereby breaking away from the existing method in which seeding is carried out after punching. Methods for the accurate detection of soybean growing locations were studied to allow punching to promote the continuous growth of soybeans that had reached the cotyledon stage. Through experiments using multiple IR sensors and a sliding mechanical device, it was found that the locations of the crop could be partially identified 3-5 days after reaching the cotyledon stage regardless of the kind of pulse crop. It can be concluded that additional studies of robust detection methods considering environmental factors and factors for crop growth are necessary.

Application of Cyber Physical System (CPS) for Risk Management of a CO2 Storage Site (이산화탄소 저장부지 위해성 관리를 위한 가상물리시스템 적용성 평가)

  • Jeong, Jina;Park, Eungyu;Jun, Seong-Chun;Kim, Hyun-Jun;Yun, Seong-Taek
    • Economic and Environmental Geology
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    • v.50 no.5
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    • pp.363-373
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    • 2017
  • In the present study, adaptability of cyber-physical system (CPS) for risk management of $CO_2$ storage site is examined and the subagging regression (SBR) method is proposed as a key component of the cyber-twin to estimate the risk due to potential $CO_2$ leakage. For these purposes, $CO_2$ concentration data monitored from a controlled $CO_2$ release field experiment is employed to validate the potentialities of the SBR method. From the validation study, it is found that the SBR method has robust estimation capability by showing minimal influence from anomalous measurements, and makes stable and sound predictions for the forthcoming $CO_2$ concentration trend. In addition, the method is found to be well suited as a tool of operational risk assessment based on real-time monitoring data due to the computational efficiency. The overall results suggest that the SBR method has potential to be an important component comprising the cyber twin of CPS for risk management of $CO_2$ storage site.

Frame Synchronization Algorithm based on Differential Correlation for Burst OFDM System (Burst OFDM 시스템을 위한 차동 상관 기반의 프레임 동기 알고리즘)

  • Um Jung-Sun;Do Joo-Hyun;Kim Min-Gu;Choi Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10C
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    • pp.1017-1026
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    • 2005
  • In burst OFDM system, the frame synchronization should be performed first for the acquisition of received frame and the estimation of the correct FFT-window position. The conventional frame synchronization algorithms using design features of the preamble symbol, the repetition pattern of the OFDM symbol by pilot sub-carrier allocation rule and Cyclic Prefix(CP), has difficulty in the detection of precise frame timing because its correlation characteristics would increase and decrease gradually. Also, the algorithm based on the correlation between the reference signal and the received signal has performance degradation due to frequency offset. Therefore, we adopt a differential correlation method that is robust to frequency offset and has the clear peak value at the correct frame timing for frame synchronization. However, performance improvement is essential for differential correlation methods, since it usually shows multiple peak values due to the repetition pattern. In this paper, we propose an enhanced frame synchronization algorithm based on the differential correlation method that shows a clear single peak value by using differential correlation between samples of identical repeating pattern. We also introduce a normalization scheme which normalizes the result of differential correlation with signal power to reduce the frame timing error in the high speed mobile channel environments.

Traveltime estimation of first arrivals and later phases using the modified graph method for a crustal structure analysis (지각구조 해석을 위한 수정 그래프법을 이용한 초동 및 후기 시간대 위상의 주시 추정)

  • Kubota, Ryuji;Nishiyama, Eiichiro;Murase, Kei;Kasahara, Junzo
    • Geophysics and Geophysical Exploration
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    • v.12 no.1
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    • pp.105-113
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    • 2009
  • The interpretation of observed waveform characteristics identified in refraction and wide-angle reflection data increases confidence in the crustal structure model obtained. When calculating traveltimes and raypaths, wavefront methods on a regular grid based on graph theory are robust even with complicated structures, but basically compute only first arrivals. In this paper, we develop new algorithms to compute traveltimes and raypaths not only for first arrivals, but also for fast and later reflection arrivals, later refraction arrivals, and converted waves between P and S, using the modified wavefront method based on slowness network nodes mapped on a multi-layer model. Using the new algorithm, we can interpret reflected arrivals, Pg-later arrivals, strong arrivals appearing behind Pn, triplicated Moho reflected arrivals (PmP) to obtain the shape of the Moho, and phases involving conversion between P and S. Using two models of an ocean-continent transition zone and an oceanic ridge or seamount, we show the usefulness of this algorithm, which is confirmed by synthetic seismograms using the 2D Finite Difference Method (2D-FDM). Characteristics of arrivals and raypaths of the two models differ from each other in that using only first-arrival traveltime data for crustal structure analysis involves risk of erroneous interpretation in the ocean-continent transition zone, or the region around a ridge or seamount.

Application of Inference Models for Estimating Parameters of a Catchment Modelling System (추론모델을 통한 강우-유출모형 매개변수의 간접추정법 적용)

  • Choi, Kyung-Sook
    • Journal of Korea Water Resources Association
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    • v.36 no.4
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    • pp.587-596
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    • 2003
  • Application of a catchment modelling system requires recorded information to ascertain the reliability and robustness of the predicted flow conditions. Where this recorded information is not available, the necessary information for reliable and robust predictions must be obtained from other available information sources. The alternative approach presented in this paper used inference models for getting this necessary information that is required to calibrate and validate the catchment modelling system for both an ungauged and a gauged catchments. In this study, inference models were developed for determination of control parameters of the Storm Water Management Model (SWMM), mainly based on landuse component of the catchment, which is a major factor to impact on quantity and quality of catchment runoff. Results from the study show that the new approach for determination of the spatially variable control parameters produced more accurate estimates than a traditional approach. Also, the number of control parameters estimated can be reduced significantly as the proposed method only requires determination of control parameters associated with each land use of the catchment while a traditional approach needs to assign a number of control parameters for a number of subcatchment.