• 제목/요약/키워드: model averaging

검색결과 300건 처리시간 0.03초

오차 계산 방식에 따른 사료용 벼 품종의 품종모수 추정치 불확도 비교 (Comparison between Uncertainties of Cultivar Parameter Estimates Obtained Using Error Calculation Methods for Forage Rice Cultivars)

  • 조영상;현신우;김광수
    • 한국농림기상학회지
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    • 제25권3호
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    • pp.129-141
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    • 2023
  • 작물 모형은 작물의 유전적 특성을 나타내는 품종모수를 요구하며, 품종모수는 작물의 개별 품종별로 추정되어야 한다. 품종모수의 추정에는 고품질의 많은 생육 자료가 요구되지만, 자료의 생산에 상당한 비용이 필요하다. 비교적 낮은 품질의 가용성이 높은 자료를 활용하는 대신, 대량의 랜덤 모수를 생성하고 이를 평가하여 품종모수를 추정할 수 있다. 본 연구에서는 SIMPLE 작물 모델의 불확도를 최소화하기 위해 품종모수 추정 방식을 비교하고, 두 앙상블 방식과 대한 비교를 하였다. 모수 추정을 위한 Metropolis-Hastings (MH) 알고리즘에 대한 목적함수로 로그 가능도(log-likelihood: LL)와 generic composite similarity measure (GCSM)를 사용하였다. 또한 품종모수의 평균값을 사용한 예측(Epm)과 개별 모수들로부터 얻어진 추정값의 평균값(Eem)의 일치도를 분석하여 앙상블 방식에 따른 불확도 변화를 파악하였다. 국내에서 재배되는 사료용 벼 품종인 조우 벼와 영우 벼를 대상으로 품종모수를 추정하였다. 2013년, 2014년, 2016년에 대한 수원, 전주, 나주, 익산에 위치한 실험포장에서 얻은 수량 관측 자료를 사용하였다. 또한 2016년부터 2018년까지 수원에서 보고된 별도의 수량 관측 자료를 사용하였다. 목적함수에 따라 추정된 품종모수의 분포에 차이가 있었다. LL을 통해 얻은 품종모수는 GCSM으로 얻은 품종모수보다 좁은 범위에 분포하였다. 두 가지 앙상블 접근법은 통계적으로 유의한 차이가 나타나지 않음을 확인하였다. GCSM의 상대적으로 높은 불확도는 수용확률을 조정하여 낮출 수 있다고 사료되고, Epm의 결과는 기존과 다른 앙상블 방식을 통해 적은 연산을 통해 불확도를 낮출 수 있음을 보인다.

Responses of Dairy Cows to Supplemental Highly Digestible Rumen Undegradable Protein and Rumen-protected Forms of Methionine

  • Sun, T.;Yu, X.;Li, S.L.;Dong, Y.X.;Zhang, H.T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권5호
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    • pp.659-666
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    • 2009
  • Metabolizable protein (MP) supply and amino acid balance in the intestine were manipulated through selection of highly digestible rumen-undegradable protein (RUP) sources and protected methionine (Met) supplementation. Four ruminallycannulated, multiparous Holstein cows averaging 193${\pm}$13 days in milk were used in a 4${\times}$4 Latin square design to assess N utilization and milk production responses to changes in RUP level, post-ruminal RUP digestibility and protected Met supplementation. Treatments were A) 14.0% crude protein (CP), 8.0% rumen degradable protein (RDP) and 6.0% RUP of low intestinal digestibility (HiRUP-LoDRUP); B) 14.1% CP, 8.1% RDP and 6.0% RUP of high intestinal digestibility (HiRUP-HiDRUP); C) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility (LoRUP-HiDRUP), and D) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility plus rumen escape sources of Met (LoRUP-HiDRUP+Met). Experimental diets were formulated to have similar concentrations of RDP, net energy of lactation ($NE_L$), neutral detergent fiber (NDF), acid detergent fiber (ADF), calcium, phosphorus and ether extract using the NRC model (2001). Results showed that dry matter intake (DMI), production of milk fat and protein were similar among treatments. Milk production was similar for diet HiRUP-LoDRUP, HiRUP-HiDRUP and LoRUP-HiDRUP+Met, and significantly higher than diet LoRUP-HiDRUP. Milk fat and protein percentage were higher for cows receiving HiDRUP treatments, with the greatest increases in the diet LoRUP-HiDRUP+Met. There was no significant change in ruminal pH, $NH_3g-N$ and volatile fatty acid (VFA) concentration among all treatments. Apparent digestibility of dry matter (DM), CP, NDF and ADF and estimated bacterial CP synthesis were similar for all treatments. Nitrogen intakes, blood and milk urea-N concentrations were significantly higher for cows receiving HiRUP diets. Urine volume and total urinary N excretion were significantly lowered by LoRUP diets. Lowering dietary RUP level while supplementing the highly digestible RUP source with rumen escape sources of Met resulted in similar milk production, maximal milk fat and protein concentration and maximum N efficiency, indicating that post-ruminal digestibility of RUP and amino acid balance in the small intestine can be more important than total RUP supplementation.

쇄파에 의한 월파의 기포분율에 대한 실험적 연구 (Experimental Study of Overtopping Void Ratio by Wave Breaking)

  • 유용욱;이종인
    • 한국해안·해양공학회논문집
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    • 제20권2호
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    • pp.157-167
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    • 2008
  • 본 연구에서는 직립 구조물 전면에서 발생하는 권파에 의한 월파의 기포분율을 수리모형실험으로 검토하였다. 구조물 직립벽 전면에서 쇄파되는 내습파랑은 쇄파와 월파 과정동안 기포를 연행하거나 액적화되며 강한 난류세기를 갖는 다위상흐름이 된다. 본 연구에서는 광섬유반사율계와 기포를 이용한 영상유속계기법으로 월파의 기포분율, 유속, 그리고 층두께를 측정하였다. 반복된 실험으로 얻어진 기포분율과 유속은 조화평균과 시간평균을 적용하여 분석하였다. 평균된 기포분율의 분포로부터 높은 기포분율은 주로 월파수괴의 전면부에서 발생하는 것을 알 수 있었으며, 구조물 상단표면에 접한 영역과 월파수괴의 후면부 영역은 상대적으로 낮은 기포분율을 보여주었다. 측정된 월파의 기포분율, 유속, 그리고 층두께로부터 월파의 흐름율과 운동량을 산정하였고, 실험결과로부터 기포분율이 중요한 인자임을 알 수 있었다. 수심평균된 기포분율, 유속, 두께의 상사적 분포특성을 이용하여 경험식을 제시하였고, 1차원적 경험식을 이용하여 흐름율과 운동량을 검토하였다.

나노웹 섬유형 전극 인터페이스와 KHU Mark2 EIT 시스템을 이용한 생체신호 동기 도전율 영상법 (Gated Conductivity Imaging using KHU Mark2 EIT System with Nano-web Fabric Electrode Interface)

  • 김태의;김현지;위헌;오동인;우응제
    • 대한의용생체공학회:의공학회지
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    • 제33권1호
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    • pp.39-46
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    • 2012
  • Electrical impedance tomography(EIT) can produce functional images with conductivity distributions associated with physiological events such as cardiac and respiratory cycles. EIT has been proposed as a clinical imaging tool for the detection of stroke and breast cancer, pulmonary function monitoring, cardiac imaging and other clinical applications. However EIT still suffers from technical challenges such as the electrode interface, hardware limitations, lack of animal or human trials, and interpretation of conductivity variations in reconstructed images. We improved the KHU Mark2 EIT system by introducing an EIT electrode interface consisting of nano-web fabric electrodes and by adding a synchronized biosignal measurement system for gated conductivity imaging. ECG and respiration signals are collected to analyze the relationship between the changes in conductivity images and cardiac activity or respiration. The biosignal measurement system provides a trigger to the EIT system to commence imaging and the EIT system produces an output trigger. This EIT acquisition time trigger signal will also allow us to operate the EIT system synchronously with other clinical devices. This type of biosignal gated conductivity imaging enables capture of fast cardiac events and may also improve images and the signal-to-noise ratio (SNR) by using signal averaging methods at the same point in cardiac or respiration cycles. As an example we monitored the beat by beat cardiac-related change of conductivity in the EIT images obtained at a common state over multiple respiration cycles. We showed that the gated conductivity imaging method reveals cardiac perfusion changes in the heart region of the EIT images on a canine animal model. These changes appear to have the expected timing relationship to the ECG and ventilator settings that were used to control respiration. As EIT is radiation free and displays high timing resolution its ability to reveal perfusion changes may be of use in intensive care units for continuous monitoring of cardiopulmonary function.

영상 기반 3차원 점군과 FUSION S/W 기반의 임분고 분석 모듈 개발 (Development of Mean Stand Height Module Using Image-Based Point Cloud and FUSION S/W)

  • 김경민
    • 한국지리정보학회지
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    • 제19권4호
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    • pp.169-185
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    • 2016
  • 최근 임상도의 신규 속성으로 임분의 평균 수고인 임분고를 추가하기 시작하였으나 전국 940만개의 포인트를 스테레오 항공사진에서 수동 측정해야 하는 어려움이 예상된다. 아울러, 항공사진에서 수고 측정 시 임연부나 묘지 주변의 수고를 측정하기 쉬워 임분 대표성이 떨어지는 한계를 가지고 있다. 본 연구에서는 고해상도 스테레오 항공사진에서 추출한 영상 기반 3차원 점군과 FUSION S/W를 활용한 임분고 추정 방법을 제안하고 임분고를 자동 분석할 수 있는 모듈을 개발하였다. 스테레오 항공사진에서 수치표면모델 3차원 점군을 추출한 후 지면점 필터링을 거쳐 수치지면모델을 추출하고 이 두 모델을 차분하여 정규수치표면모델을 제작하였다. 정규수치표면모델에서 표본점별 개체목 수관을 육안판독한 후 수관별 최고점을 추출하여 정규수치표면모델 수고를 산출하였다. 표본점에서의 실측 수고와 정규수치표면모델 수고의 RMSE를 분석한 결과 전체 표본점 평균 수고의 RMSE는 0.96m로 나타났다. 대상지 전체의 개체목 수고를 추출하기 위해 FUSION S/W를 이용하여 항공사진의 정규수치표면모델에서 개체목 수고를 자동 추출하고 이를 임상도의 임분 폴리곤 단위로 평균하여 최종 임분고를 산출하였다. 마지막으로 임분고를 보다 손쉽게 분석할 수 있는 환경을 구현하기 위해 임분고 분석 프로세스를 ArcGIS add-in 모듈 형태로 자동화하였다.

Effects of Dietary Arachidonic Acid (20:4n-6) Levels on Growth Performance and Fatty Acid Composition of Juvenile Eel, Anguilla japonica

  • Bae, Jun-Young;Kim, Dae-Jung;Yoo, Kwang-Yeol;Kim, Sun-Gyu;Lee, Jeong-Yeol;Bai, Sungchul C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권4호
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    • pp.508-514
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    • 2010
  • This study was conducted to evaluate the effects of dietary arachidonic acid (AA, 20:4n-6) levels on growth performance and body composition in juvenile eel, Anguilla japonica. Six semi-purified experimental diets were formulated to be isonitrogenous and iso-caloric containing 55.0% crude protein and 15% crude lipid (18.3 kJ of available energy $g^{-1}$). Six different levels of AA were added to the basal diet, with 0, 0.2, 0.4, 0.6, 0.8 or 1.2% on a dry matter (DM) basis, respectively ($AA_{0.07},\;AA_{0.22},\;AA_{0.43},\;AA_{0.57},\;AA_{0.78}\;or\;AA_{1.23}$). After a conditioning period, fish initially averaging 27${\pm}$0.5 g (mean${\pm}$SD) were randomly distributed into each aquarium as triplicate groups of 20 fish each. One of six experimental diets was fed on a DM basis to fish in three randomly selected aquaria at a rate of 2-3% of total body weight twice a day. At the end of the 12-week feeding trial, weight gain (WG) and feed efficiency (FE) of fish fed $AA_{0.78}$ and $AA_{1.23}$ diets were significantly higher than of fish fed $AA_{0.07},\;AA_{0.22},\;AA_{0.43}$ diets (p<0.05). Specific growth rate (SGR) of fish fed the $AA_{0.78}$ diet was significantly higher than of fish fed $AA_{0.07},\;AA_{0.22},\;AA_{0.43}$ diets (p<0.05). However, there were no significant differences in WG, SGR and FE among fish fed $AA_{0.57},\;AA_{0.78}\;or\;AA_{1.23}$ diets (p>0.05). Whole body AA deposition of fish fed the $AA_{1.23}$ diet was significantly higher than for the other diets (p<0.05). Broken-line model analysis on the basis of WG and SGR indicated that the dietary AA requirement could be greater than 0.69% but less than 0.71% of the diet in juvenile eel. The growth-promoting activity of AA observed in the present study provides strong support for the contention that dietary AA is essential for juvenile eel.

Re-evaluation of Dietary Methionine Requirement by Plasma Methionine and Ammonia Concentrations in Surgically Modified Rainbow Trout, Oncorhynchus mykiss

  • Bae, Jun-Young;Ok, Im-Ho;Lee, Seung-Hyung;Hung, Silas S.O.;Min, Tae-Sun;Bai, Sung-Chul C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제24권7호
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    • pp.974-981
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    • 2011
  • This study was designed to re-evaluate the dietary methionine requirement by means of the plasma methionine and ammonia concentrations in surgically modified rainbow trout, Oncorhynchus mykiss. A total of 35 rainbow trout averaging $505{\pm}6.5$ g (initial body weight, mean${\pm}$SD) were randomly distributed into seven groups with five fish in each group. After 48 h of feed deprivation, each group of fish was fed one of seven L-amino acid based diets containing 0.5% cystine and graded levels of methionine (0.25, 0.40, 0.50, 0.60, 0.70, 0.80 or 0.95% of diet, dry matter bases) by intubation at 1% body weight on dry matter basis. Blood samples were taken at 0, 5 and 24 h after intubation. Post-prandial plasma free methionine concentrations (PPmet, 5 h after intubation) and post-absorptive plasma free methionine concentrations (PAmet, 24 h after intubation) of fish fed diets containing 0.60% or higher methionine were significantly (p<0.05) higher than those of fish fed diets containing 0.50% or lower methionine. PPmet and PAmet in fish fed diets containing 0.60% or higher methionine were not significantly different except PPmet of fish fed diet containing 0.95% methionine. Post-prandial plasma ammonia concentrations (PPA, 5 h after intubation) of fish fed diets containing 0.70% or higher methionine were significantly higher than those of fish fed diets containing 0.60% or lower methionine, and PPA of fish fed diets containing 0.25 and up to 0.60% methionine were not significantly different from each other. Broken-line model analyses on PPmet, PAmet, and PPA indicated that the dietary methionine requirement of rainbow trout was between 0.59 (1.69) and 0.67 (1.91) % of diets (% dietary protein bases) when the diets contained 0.5% cystine.

바이트 평균의 Gray-Scale화를 통한 Signature가 존재하지 않는 멀티미디어 데이터 조각 파일 타입 분류 연구 (Classification of Non-Signature Multimedia Data Fragment File Types With Byte Averaging Gray-Scale)

  • 윤현호;김재헌;조현수;원종은;김견우;조재현
    • 정보보호학회논문지
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    • 제30권2호
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    • pp.189-196
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    • 2020
  • 일반적으로 시그니처와 파일 메타정보가 없는 파편화된 파일은 복구가 어렵다. 특히 멀티미디어 파일은 파편화 가능성이 크고 높은 엔트로피를 가지고 있으므로 현재 시그니처 기반의 카빙으로는 복구하는 것이 거의 불가능하다. 이러한 문제를 해결하기 위해 파편화된 파일에 대한 연구가 진행되고 있지만 멀티미디어 파일에 대한 연구는 부족한 실정이다. 본 논문은 시그니처(Signature)와 파일 메타정보가 없는 파편화된 멀티미디어 파일의 타입을 분류하는 연구이다. 파일 타입에 따라 특정 바이트 값의 빈도 차이를 통해 각 파일 타입의 특징값을 추출하며, 그에 맞는 Gray-Scale 테이블을 설계하고 CNN(Convolutional Neural Networks) 모델을 이용하여 JPG, PNG, H.264, WAV 총 4가지 멀티미디어의 파일 타입을 분류하는 방법을 제시한다. 본 논문을 통해 시그니처와 파일 메타정보가 없는 파편화된 파일 타입의 분류 연구를 촉진하여 다양한 파일의 복구 가능성을 높일 수 있을 것으로 기대된다.

Determination of the dietary lysine requirement by measuring plasma free lysine concentrations in rainbow trout Oncorhynchus mykiss after dorsal aorta cannulation

  • Yun, Hyeonho;Park, Gunjun;Ok, Imho;Katya, Kumar;Hung, Silas SO;Bai, Sungchul C.
    • Fisheries and Aquatic Sciences
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    • 제19권1호
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    • pp.4.1-4.7
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    • 2016
  • This study evaluated the dietary lysine requirement by measuring the plasma free lysine concentrations in rainbow trout, Oncorhynchus mykiss after dorsal aorta cannulation. A basal diet containing 36.6 % crude protein (29.6 % crystalline amino acids mixture, 5 % casein and 2 % gelatin) was formulated to one of the seven L-amino acid based diets containing graded levels of lysine (0.72, 1.12, 1.52, 1.92, 2.32, 2.72 or 3.52 % dry diet). A total of 35 fish averaging $512{\pm}6.8g$ ($mean{\pm}SD$) were randomly distributed into seven groups with five fish in each group. After 48 h of feed deprivation, each group of fish was fed one of the experimental diets by intubation at 1 % body weight. Blood samples were taken at 0, 5 and 24 h after intubation. Post-prandial plasma free lysine concentrations (PPlys, 5 h after intubation) of fish fed diets containing ${\geq}2.32%$ lysine were higher than those of fish fed diets containing ${\leq}1.92%$ lysine. Post-absorptive free lysine concentrations (PAlys, 24 h after intubation) of fish fed diets containing 2.32 and 3.52 % lysine were higher than those of fish fed diets containing ${\leq}1.52%$ lysine. The brokenline regression analysis on the basis of PPlys and PAlys indicated that the lysine requirement of rainbow trout could be 2.34 and 2.20 % in diet. Therefore, these results strongly suggested that the dietary lysine requirement based on the broken-line model analyses of PPlys and PAlys could be greater than 2.20 % but less than 2.34 % (corresponding to be $6.01%{\leq},but{\leq}6.39%$ in dietary protein basis, respectively) in rainbow trout. Also, these results shown that the quantitative estimation of lysine requirement by using PPlys and PAlys could be an acceptable method in fish.

양어사료의 어분대체품 개발의 경제성 분석 (Economic Evaluation of The Newly Developed Fish Meal Analog (BAIFA-M))

  • 김기수;배승철;최재영;김우경
    • 수산경영론집
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    • 제29권1호
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    • pp.121-137
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    • 1998
  • This study was conducted to examine the economic evaluation of the newly developed fish meal analog (BAIFA-M) in Korean rockfish feed. A raw fish feed (MP) and two commercially formulated diets (EP) were employed to compare weight gain (WG), feed conversion ratio (FCR) and survival rate (SR) from the sea cage culture system. By using the economic model in the practical sea cage culture system, feed cost, production cost and gross profit per kg production, rate of profit to gross revenue (RPGR), and internal rate of return (IRR) were calculated based upon the results of the experiment and the information of the private aquaculture farm (Young Chang) in Tong young, Korean. IRR criteria is one of the popular economic feasibility analysis methods applicable far aquaculture industry. This is an economic evaluation method to compare the given interest rate or the discount rate with IRR which can be calculated by the difference between the present value of the benefit stream and of the cost stream. The benefits of using EP on WG, FCR, SR, and production cost will be emphasized in this study. Fish averaging 20$\pm$3.6g (Mean$\pm$SD) were randomly distributed in each small cage (6m$\times$6m) as groups of 2,000 fish. By using 3 large size cages (12m$\times$12m), 12 small cages were constructed, and only 9 small cages were employed for three replicates of each diet treatment. To compare with MP diet, two sinking EP diets were designed by our laboratory and produced by the local feed company who wanted to promote these EP diets for the mass cage culture of Korean rockfish in the future. Two EP diets contain white fish meal and/or BAIFA-M as the main animal protein sources : WFM diet, maximum 43% of white fish meal : BAIEA- M diet, 30% of white fish meal nab replaced by BAIFA- M from WFM diet. Results are summarized in Table 1. Fish fed MP diet showed significantly lower SR than does fish fed two EP diets(P<0.05). However, there Were no significant difference on FCR among fish fed three practical diets. Table 1. Average feed conversion ratio (FCR), accumulative average survival rate (SR) and economic evaluation data far three practical diets. As we expected, BAIFA-M diet is more economical than WFM diet as well as MP diet. Feed cost and production cost per kg production from BAIEA - M diet were lower than those from WFM and MP diets. Moreover, gross profit per Kg production, RPGR and IRR from BAIFA- M diet were higher than those from WFM and MP diets. This economic evaluation study clearly indicated that MP diet should be replaced by the commerical formulated EP diets as soon as possible in the near future because MP diet is not economical in the practical sea cage culture system.

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