• Title, Summary, Keyword: logistic curve

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Estimation of Growth Curve Parameters for Body Weight and Measurements in Castrated Hanwoo (Bostaurus Coreanae) (한우 거세우의 체중 및 체형에 대한 성장곡선 모수 추정)

  • Choi, Te-Jeong;Seo, Kang-Seok;Kim, Si-Dong;Cho, Kwang-Hyun;Choi, Jae-Gwan;Hwang, In-Ho;Choi, Ho-Sung;Park, Chul-Jin
    • Journal of Animal Science and Technology
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    • v.50 no.5
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    • pp.601-612
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    • 2008
  • This study was conducted to figure out how the shape of Hanwoo changes over time, examine the rank correlations between the carcass traits which are the selection traits and parameters of growth curve, and determine the correlation between body shape and carcass. Body weight, body measurements and carcass traits were measured from 161 castrated Hanwoo, and 12 growth traits and 5 carcass traits were investigated in total. The logistic model(Nelder, 1961) used for the estimation of growth curve parameters and growth characteristics at inflection point were calculated by these growth curve parameters. The value of this parameter was greatest for pinbone width, which suggests that it is an early ripening trait, while it was lowest for chest girth, suggesting it to be a late ripening trait. The rank correlations of chest depth, chest width, and hip width with backfat thickness steadily increased from 6 to 24 months, while the rank correlations of other traits decreased after 18 months until 24 months of age. Only phenotypic records were analyzed in this study, but for examine the genetic changes over growth phase in Hanwoo, if another additional genetic analysis like as estimation of genetic parameters should achieve, body measurements may be useful traits in proven bull selection.

Estimation of Compressive Strength of Fly Ash Concrete subjected to High Temperature (고온조건하에서 플라이애시를 사용한 콘크리트의 압축강도증진 해석)

  • Han Min-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.6 no.3
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    • pp.99-105
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    • 2006
  • In this paper, the estimation of compressive strength of concrete incorporating fly ash subjected to high temperature is discussed. Ordinary Portland cement and fly ash cement(30% of fly ash) were used, respectively. Water to binder ration ranging from 30% to 60% and curing temperature ranging from $20^{\circ}C{\sim}65^{\circ}C$ were also adopted for the experimental parameters. According to results, at the high temperature, FAC had higher strength development at early age than OPC concrete and it kept its high strength development at later age due to accelerated pozzolanic reaction subjected to high temperature. For strength estimation, Logistic model based on maturity equation and Carino model based on equivalent age were applied to verify the availability of estimation model. It shows that fair agreements between calculated values and measured values were obtained evaluating compressive strength with logistic curve. The application of logistic model at high temperature had remarkable deviations in the same maturity. Whereas, the application of Carino model showed good agreements between calculated values and measured ones regardless of type of cement and W/B. However, some correction factors should be considered to enhance the accuracy of strength estimation of concrete.

Estimation of Compressive Strength of Concrete Using Blast Furnace Slag Subjected to High Temperature Environment (고온환경 조건하에서 고로슬래그를 사용한 콘크리트의 압축강도 증진 해석)

  • Han, Min-Cheol;Shin, Byung-Cheol
    • Journal of Environmental Science International
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    • v.16 no.3
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    • pp.347-355
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    • 2007
  • In this paper, estimation of the compressive strength of the concrete incorporating blast furnace slag subjected to high temperature was discussed. Ordinary Portland cement and blast furnace slag cement (BSC;30% of blast furnace slag) were used, respectively. Water to binder ratio ranging from 30% to 60% and curing temperature ranging from $20^{\circ}C{\sim}65^{\circ}C$ were also chosen for the experimental parameters, respectively. At the high temperature, BSC had higher strength development at early age than OPC concrete and it kept its high strength development at later age due to accelerated latent hydration reaction subjected to high temperature. For the strength estimation, the Logistic model based on maturity equation and the Carino model based on equivalent age were applied to verify the availability of estimation model. It was found that fair agreements between calculated values and measured values were obtained evaluating compressive strength with logistic curve. The application of logistic model at high temperature had remarkable deviations in the same maturity. Whereas, the application of Carino model showed good agreements between calculated values and measured ones regardless of type of cement and W/B. However, some correction factors should be considered to enhance the accuracy of strength estimation of concrete.

Proposition of the Removal Time of From Based on the Analysis of Strength Development of Concrete Using Blast-furnace Slag Cement (고로슬래그 시멘트를 사용한 콘크리트의 강도 증진 해석에 의한 거푸집 존치기간의 제안)

  • 표대수;유호범;한민철;윤기원;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.163-168
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    • 2000
  • In this paper, removal times of from from concrete using OPC( Ordinary Portland Cement) and BSC(Blast-furnace Slag cement) are suggested by appling logistic curve, which evaluates the strength development of concrete with maturity. W/B, kinds of cement and curing temperatures are selected as test parameters. According to the results, the estimation of strength development by logistic curve has a good agreement between calculated values. As for the removal time of from suggested in this paper, as W/B increase, curing temperature decrease and BSC in used, removal they times of from are shown to be kept longer. Removal times of from from concrete using OPC suggested in this paper are shorter by about 2~3day than those of standard specifications provided in KCI in the rang of over $20^{\circ}C$, while they takes 4~5 day shorter compared with those of standard specifications Provided in KCI in the range of 10~$20^{\circ}C$. Removal times of from for concrete using OPC are longer than those using BSC by about 1 day.

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A Study on the Development of Strength Control Model of Concrete Structure using Maturity Method (적산온도 기법을 활용한 콘크리트구조물의 강도관리모델 개발에 관한 연구)

  • 길배수;윤종기;김재환;김정일;남재현;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.711-716
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    • 2002
  • The purpose of this study is to develop a strength control model for application of variety internal condition at construction field. The results of this study were shown as follows ; 1) According to results of compressive strength of concrete by using equivalent age, new curve is applicable of construction field because there is similar relation with logistic curve. 2) It is shown that the construction period is shorten by reduction of the formwork removal time, because a predicted compressive strength of using the new curve is high than proposed compressive strength of standard.

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Modeling of The Learning-Curve Effects on Count Responses (개수형 자료에 대한 학습곡선효과의 모형화)

  • Choi, Minji;Park, Man Sik
    • The Korean Journal of Applied Statistics
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    • v.27 no.3
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    • pp.445-459
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    • 2014
  • As a certain job is repeatedly done by a worker, the outcome comparative to the effort to complete the job gets more remarkable. The outcome may be the time required and fraction defective. This phenomenon is referred to a learning-curve effect. We focus on the parametric modeling of the learning-curve effects on count data using a logistic cumulative distribution function and some probability mass functions such as a Poisson and negative binomial. We conduct various simulation scenarios to clarify the characteristics of the proposed model. We also consider a real application to compare the two discrete-type distribution functions.

The probabilistic estimation of inundation region using a multiple logistic regression analysis (다중 Logistic 회귀분석을 통한 침수지역의 확률적 도출)

  • Jung, Minkyu;Kim, Jin-Guk;Uranchimeg, Sumiya;Kwon, Hyun-Han
    • Journal of Korea Water Resources Association
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    • v.53 no.2
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    • pp.121-129
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    • 2020
  • The increase of impervious surface and development along the river due to urbanization not only causes an increase in the number of associated flood risk factors but also exacerbates flood damage, leading to difficulties in flood management. Flood control measures should be prioritized based on various geographical information in urban areas. In this study, a probabilistic flood hazard assessment was applied to flood-prone areas near an urban river. Flood hazard maps were alternatively considered and used to describe the expected inundation areas for a given set of predictors such as elevation, slope, runoff curve number, and distance to river. This study proposes a Bayesian logistic regression-based flood risk model that aims to provide a probabilistic risk metric such as population-at-risk (PAR). Finally, the logistic regression model demonstrates the probabilistic flood hazard maps for the entire area.

Case Study on Measuring Technology Level Applying Growth Curve Model: Three Core Areas of Fishery Science and Technology (성장곡선 모형 적용을 통한 기술수준평가 사례 연구 : 특정 수산과학기술 분야를 중심으로)

  • Kim, Wan-Min;Park, Ju-Chan;Bark, Pyeng-Mu
    • The Journal of Fisheries Business Administration
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    • v.46 no.3
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    • pp.103-118
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    • 2015
  • The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.

Ecological Buffer Analysis of Western DMZ and Vicinity using Logistic Function Derived from TVI-Distance Curve (TVI-거리함수를 이용한 서부 DMZ 및 민통지역의 생태적 보전폭원 조사)

  • Kim, Sang-Wook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.4
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    • pp.95-104
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    • 2006
  • The DMZ is a 248km long thin green line which has various landscapes of fields, hills and mountains. This study focused on western part of DMZ and vicinity which consist of abandoned rice paddy, wetlands and fields. The main purpose of this study is to detect the vegetation vitality from the western part of MDL to DMZ vicinity and identify and quantify ecological buffer(ecotone) width adopting logistic function derived from 'Vegetation Index-distance curve' using an Landsat ETM+ image acquired on June of 2002. Green leaf vegetation was quantified to identify the ecotone buffer in western DMZ and vicinity(civilian control area: CCA) using Transformed Vegetation Index(TVI) which is one of common measurement among various indices. Vegetation measurement from Military Demarcation Line(MDL) to vicinity area was investigated at 500m intervals to 10kms of southern and northern part of western DMZ and vicinity. The Logistic function models the sigmoid curve of growth with three stages of growth of initial competition and maturity. In the TVI-distance logistic curve, the maturity is high vegetation vitality, the competition is vitality changing, and the initial is low vitality. In the TVI-distance curve, maturity area of high TVI value is core area for ecological conservation, and the competition area between inflection points can be an ecotone(ecological buffer). In case of southern part, maximum TVI value is 221.92 and minimum is 207.16, and maximum TVI of northen part is 215.32 and minimum is 188.35. That means forest devastation of north Korean part of DMZ and vicinity is severer than that of south Korea. The width of core area for ecological conservation is 2,311m, and ecotone in the southern part is 5,339m, so minimum width from MDL for ecological conservation can be computed as 7,651m. In case of Northern part, the width of core area is 1,841m, and ecotone buffer is 5,014m, so ecological conservation width can be estimated as 6,855m. In case of northen part, width of estimated core area is less than that of DMZ width, which means ecological disturbance is very severe in northern part of western DMZ.

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A Software Reliability Growth Model Based on Gompertz Growth Curve (Gompertz 성장곡선 기반 소프트웨어 신뢰성 성장 모델)

  • Park Seok-Gyu;Lee Sang-Un
    • The KIPS Transactions:PartD
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    • v.11D no.7
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    • pp.1451-1458
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    • 2004
  • Current software reliability growth models based on Gompertz growth curve are all logarithmic type. Software reliability growth models based on logarithmic type Gompertz growth curve has difficulties in parameter estimation. Therefore this paper proposes a software reliability growth model based on the logistic type Gompertz growth curie. Its usefulness is empirically verified by analyzing the failure data sets obtained from 13 different software projects. The parameters of model are estimated by linear regression through variable transformation or Virene's method. The proposed model is compared with respect to the average relative prediction error criterion. Experimental results show that the pro-posed model performs better the models based on the logarithmic type Gompertz growth curve.