• Title/Summary/Keyword: Model variability

Search Result 956, Processing Time 0.03 seconds

A Method for Deriving an Optimal Product Feature Configuration Considering Feature Interaction (상호작용을 고려한 최적의 제품휘처형상 도출 방법)

  • Lee, Kwanwoo
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.2
    • /
    • pp.115-120
    • /
    • 2014
  • Many product line engineering methods use the feature model to structure commonality and variability among products in terms of features and to derive a product feature configuration, which is the set of features required for the development of a product. Features to be selected during product derivation are mainly determined based on the quality attributes required for a product. Most methods published so far derived an optimal product feature configuration through linear co-relationship between features and quality attributes. However, the co-relationship between features and quality attributes can be formulated as a non-linear function because of feature interactions. This paper proposes a method that derives an optimal product feature configuration considering feature interactions. Four product line cases are used to validate the proposed methods.

Production of Future Wind Resource Map under Climate Change over Korea (기후변화를 고려한 한반도 미래 풍력자원 지도 생산)

  • Kim, Jin Young;Kim, Do Yong
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.25 no.1
    • /
    • pp.3-8
    • /
    • 2017
  • In this study future wind resource maps have been produced under climate change scenario using ensemble regional climate model weather research and forecasting(WRF) for the period from 2045 to 2054(mid 21st century). Then various spatiotemporal analysis has been conducted in terms of monthly and diurnal. As a result, monthly variation(monsoon circulation) was larger than diurnal variation(land-sea circulation) throughout the South Korea. Strong wind area with high wind power energy was varied on months and regions. During whole years, strong wind with high wind resource was pronounced at cold(warm) months in particular Gangwon mountainous and coastal areas(southwestern coastal area) driven by strong northwesterly(southwesterly). Projected strong and weak wind were presented in January and September, respectively. Diurnal variation were large over inland and mountainous area while coastal area were small. This new monthly and diurnal variation would be useful to high resource area analysis and long-term operation of wind power according to wind variability in future.

The National Forest Inventory of the United States of America

  • McRoberts, Ronald E.
    • Journal of Forest and Environmental Science
    • /
    • v.24 no.3
    • /
    • pp.127-135
    • /
    • 2008
  • The mission of the Forest Inventory and Analyis (FIA) program of the Forest Service, U.S. Department of Agriculture, is to conduct the national forest inventory of the United States of America for purposes of estimating the area of forest land; the volume, growth, and removal of forest resources; and the health of the forest. Users of FIA data, estimates, and related products include land managers, policy and decision-makers, forest industry, environmental organizations, and university researchers. To accomplish its mission, the FIA program has established a sampling design with an intensity of approximately one permanent plot per 2,400 ha across the entire country. Depending on the region of the country, each plot is remeasured at intervals of five or 10 years. The program releases data annually and reports estimates at the county level for each state every five years. Due to budgetary constraints and natural variability among plot observations, sufficient numbers of plots cannot be measured to satisfy precision guidelines for the estimates of many variables unless the estimation process is enhanced using ancillary data. Classified satellite imagery has been demonstrated to be a source of ancillary data that can be used with stratified estimation techniques to increase the precision of estimates with little corresponding increase in costs. A crucial factor restricting the utility of FIA data is that the exact locations of inventory plots cannot be released to the public. Thus, users are generally not able to obtain estimates for small areas or for their own areas of interest if exact plot locations are required. To compensate, satellite imagery, inventory plot data, and the k-Nearest Neighbors technique are being used to construct Internet-based maps of forest attributes from which estimates for arbitrary user-defined areas of interest may be obtained.

  • PDF

Subsequent application of self-organizing map and hidden Markov models infer community states of stream benthic macroinvertebrates

  • Kim, Dong-Hwan;Nguyen, Tuyen Van;Heo, Muyoung;Chon, Tae-Soo
    • Journal of Ecology and Environment
    • /
    • v.38 no.1
    • /
    • pp.95-107
    • /
    • 2015
  • Because an ecological community consists of diverse species that vary nonlinearly with environmental variability, its dynamics are complex and difficult to analyze. To investigate temporal variations of benthic macroinvertebrate community, we used the community data that were collected at the sampling site in Baenae Stream near Busan, Korea, which is a clean stream with minimum pollution, from July 2006 to July 2013. First, we used a self-organizing map (SOM) to heuristically derive the states that characterizes the biotic condition of the benthic macroinvertebrate communities in forms of time series data. Next, we applied the hidden Markov model (HMM) to fine-tune the states objectively and to obtain the transition probabilities between the states and the emission probabilities that show the connection of the states with observable events such as the number of species, the diversity measured by Shannon entropy, and the biological water quality index (BMWP). While the number of species apparently addressed the state of the community, the diversity reflected the state changes after the HMM training along with seasonal variations in cyclic manners. The BMWP showed clear characterization of events that correspond to the different states based on the emission probabilities. The environmental factors such as temperature and precipitation also indicated the seasonal and cyclic changes according to the HMM. Though the usage of the HMM alone can guarantee the convergence of the training or the precision of the derived states based on field data in this study, the derivation of the states by the SOM that followed the fine-tuning by the HMM well elucidated the states of the community and could serve as an alternative reference system to reveal the ecological structures in stream communities.

Genetic parameters for marbling and body score in Anglonubian goats using Bayesian inference via threshold and linear models

  • Figueiredo Filho, Luiz Antonio Silva;Sarmento, Jose Lindenberg Rocha;Campelo, Jose Elivalto Guimaraes;de Oliveira Almeida, Marcos Jacob;de Sousa, Antonio Junior;da Silva Santos, Natanael Pereira;da Silva Costa, Marcio;Torres, Tatiana Saraiva;Sena, Luciano Silva
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.9
    • /
    • pp.1407-1414
    • /
    • 2018
  • Objective: The aim of this study was to estimate (co) variance components and genetic parameters for categorical carcass traits using Bayesian inference via mixed linear and threshold animal models in Anglonubian goats. Methods: Data were obtained from Anglonubian goats reared in the Brazilian Mid-North region. The traits in study were body condition score, marbling in the rib eye, ribeye area, fat thickness of the sternum, hip height, leg perimeter, and body weight. The numerator relationship matrix contained information from 793 animals. The single- and two-trait analyses were performed to estimate (co) variance components and genetic parameters via linear and threshold animal models. For estimation of genetic parameters, chains with 2 and 4 million cycles were tested. An 1,000,000-cycle initial burn-in was considered with values taken every 250 cycles, in a total of 4,000 samples. Convergence was monitored by Geweke criteria and Monte Carlo error chain. Results: Threshold model best fits categorical data since it is more efficient to detect genetic variability. In two-trait analysis the contribution of the increase in information and the correlations between traits contributed to increase the estimated values for (co) variance components and heritability, in comparison to single-trait analysis. Heritability estimates for the study traits were from low to moderate magnitude. Conclusion: Direct selection of the continuous distribution of traits such as thickness sternal fat and hip height allows obtaining the indirect selection for marbling of ribeye.

Source of the Variation in Meat and Bone Meal Nutritional Quality

  • Hendriks, W.H.;Cottam, Y.H.;Morel, P.C.H.;Thomas, D.V.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.1
    • /
    • pp.94-101
    • /
    • 2004
  • The gross composition, gross amino acid content, apparent ileal amino acid digestibility and apparent ileal digestible amino acid content from 64 commercially produced meat and bone meals were statistically analysed. The samples were produced by 22 plants over a 2.5 year period with eight plants using batch dry rendering and 14 plants using low temperature rendering. A linear model with method and time of year (period) as fixed effects, plant within method as a random effect and sheep percent as a covariate was fitted to the composition data. The majority of the variation in the gross composition, amino acid digestibility and digestible amino acid content was explained by differences between plants using the same method. Neither rendering season nor origin of the raw materials contributed significantly to the observed variation in meat and bone meal protein quality. Rendering method (low temperature or batch rendering) had a significant effect on the variation observed in gross fat content, gross energy content, pepsin nitrogen digestibility, protein solubility and total lanthionine content. The digestibility of a number of amino acids and the apparent digestible content of arginine, cysteine, aspartic acid, proline and hydroxyproline were also significantly affected by rendering method. On average, batch dry and low temperature rendering systems produce meat and bone meals of similar nutritional quality. The variation between plant and within plant, however, is large, indicating that purchasing meat and bone meal from the same plant does not guarantee a consistent quality.

Hypergraph model based Scene Image Classification Method (하이퍼그래프 모델 기반의 장면 이미지 분류 기법)

  • Choi, Sun-Wook;Lee, Chong Ho
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.24 no.2
    • /
    • pp.166-172
    • /
    • 2014
  • Image classification is an important problem in computer vision. However, it is a very challenging problem due to the variability, ambiguity and scale change that exists in images. In this paper, we propose a method of a hypergraph based modeling can consider the higher-order relationships of semantic attributes of a scene image and apply it to a scene image classification. In order to generate the hypergraph optimized for specific scene category, we propose a novel search method based on a probabilistic subspace method and also propose a method to aggregate the expression values of the member semantic attributes that belongs to the searched subsets based on a linear transformation method via likelihood based estimation. To verify the superiority of the proposed method, we showed that the discrimination power of the feature vector generated by the proposed method is better than existing methods through experiments. And also, in a scene classification experiment, the proposed method shows a competitive classification performance compared with the conventional methods.

Genetic Parameters for Linear Type Traits and Milk, Fat, and Protein Production in Holstein Cows in Brazil

  • Campos, Rafael Viegas;Cobuci, Jaime Araujo;Kern, Elisandra Lurdes;Costa, Claudio Napolis;McManus, Concepta Margaret
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.28 no.4
    • /
    • pp.476-484
    • /
    • 2015
  • The objective of this study was to estimate genetic and phenotypic parameters for linear type traits, as well as milk yield (MY), fat yield (FY) and protein yield (PY) in 18,831 Holstein cows reared in 495 herds in Brazil. Restricted maximum likelihood with a bivariate model was used for estimation genetic parameters, including fixed effects of herd-year of classification, period of classification, classifier and stage of lactation for linear type traits and herd-year of calving, season of calving and lactation order effects for production traits. The age of cow at calving was fitted as a covariate (with linear and quadratic terms), common to both models. Heritability estimates varied from 0.09 to 0.38 for linear type traits and from 0.17 to 0.24 for production traits, indicating sufficient genetic variability to achieve genetic gain through selection. In general, estimates of genetic correlations between type and production traits were low, except for udder texture and angularity that showed positive genetic correlations (>0.29) with MY, FY, and PY. Udder depth had the highest negative genetic correlation (-0.30) with production traits. Selection for final score, commonly used by farmers as a practical selection tool to improve type traits, does not lead to significant improvements in production traits, thus the use of selection indices that consider both sets of traits (production and type) seems to be the most adequate to carry out genetic selection of animals in the Brazilian herd.

A Preliminary Study on UAV Photogrammetry for the Hyanho Coast Near the Military Reservation Zone, Eastern Coast of Korea (동해안 군사시설보호구역 주변 향호 연안역을 대상으로 무인항공사진측량에 관한 예비 연구)

  • Kim, Baeck-Oon;Yun, Kong-Hyun;Chang, Tae-Soo;Bahk, Jang-Jun;Kim, Seong-Pil
    • Ocean and Polar Research
    • /
    • v.39 no.2
    • /
    • pp.159-168
    • /
    • 2017
  • To evaluate the accuracy of UAV photogrammetry for Hyangho coast, eastern coast of Korea, we conducted a field experiment wherein UAV photogrammetry test was repeated three times. Since the Haygho coast is located within a military reservation zone, it was necessary to obtain permission to gain access to the beach and to have sensitive aerial photographs showing military facilities inspected and cropped. The standard deviation of the UAV shooting position between the three tests was less than 1 m, but repeatability of footprint on the ground was low due to wind-driven variability of the UAV pose. Self-calibrating bundle adjustment(SCBA) of implementing non-metric camera calibration was failed in one test. In two tests, the vertical error was twice as large as the pixel size except for those areas that were subject to security inspection and cropping. Given the problems that can arise with regard to the repeatability of the shooting area as well as the possibility of failure with regard to SCBA, we strongly recommend that UAV photogrammetry in coastal areas needs to be repeated at least twice.

An Analysis of SEASAT Altimeter Measurements over the East China Sea (동지나해(東支那海)의 SEASAT 위성(衛星) 고도계(高度計) 자료분석(資料分析))

  • Choi, Byung Ho
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.5 no.3
    • /
    • pp.85-93
    • /
    • 1985
  • An initial attempt was made to investigate sea surface topography in the East China Sea using the SEASAT-A altimeter data. Over the study area for the two major typhoon surges generated during the SEASAT mission, space and time variability of the shallow water tides, meteorological effects and earth tides were removed from the altimetric measurements using the systematic procedures which include the two-dimensional sea model of the East China Sea. The analysis of ten flights over the ground track for the typhoon periods were presented and discussions were made for further studies. This initial study has been undertaken in association with the programme of establishment of systematic altimeter data reduction system for the study of shelf dynamics in the East China Sea.

  • PDF