• 제목/요약/키워드: The Logistic Curve

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토종닭 순계 12계통과 성별에 따른 성장능력 비교 연구 (A Comparative Study on the Growth Performance of Korean Indigenous Chicken Pure Line by Sex and Twelve Strains)

  • 김기곤;박병호;전익수;추효준;함진주;박건;차재범
    • 한국가금학회지
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    • 제48권4호
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    • pp.193-206
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    • 2021
  • 이 연구는 국립축산과학원 가금연구소에서 보유하고 있는 토종닭 순계 12계통의 육성기 성장능력을 파악하기 위해 생시(0주령)부터 16주령까지 2주 간격으로 체중, 증체량을 측정하고, 성장곡선을 추정하여 제시하였다. 각 주령별 체중에 대한 성별 효과와 계통 효과는 전 기간에서 각각 유의적인 차이를 보였으며 전 기간 체중은 수컷이 암컷보다 유의적으로 무겁게 나타났다. 계통별 체중 차이는 코니쉬 품종과 그 외 품종으로 구분되어 나타났고, 코니쉬 품종이 생시 체중을 제외하고 다른 품종에 비해 약 2배 정도 체중이 무거운 경향을 보였다. 증체량의 경우 생시부터 6주령까지 증체량이 빠르게 증가하는 경향과 이후 피크에 도달하고 12주령부터 14주령까지 기간에 증체량이 감소하는 경향은 모든 성별과 계통에서 공통적으로 나타났다. 그러나 성별과 계통에 따라 증체량의 피크 도달 시점과 횟수의 차이를 보였다. 주령별 체중 간 상관분석 결과, 토종닭 시장 출하 주령인 10주령과 8주령 체중에서 가장 높은 표현형 상관계수를 나타났다. 증체량과 증체량 간의 상관분석 결과는 0-2주령 증체량과 2~4주령 증체량 간 표현형 상관계수를 제외하고 -0.16에서 0.29로 낮은 표현형 상관을 보였다. 성장곡선 모형의 결정계수와 수정된 결정계수는 99.1~99.9로 계통과 성별에 상관없이 모두 높은 적합도를 나타냈다. 그러나 각 모형별 적합도는 성별과 계통에 따라 차이가 나타났다. 암컷의 성장 곡선은 D계통을 제외한 모든 계통에서 Von Betalanffy 모형이 가장 높은 적합도를 보였다. 반면에 수컷의 성장 곡선은 C계통을 제외한 모든 계통에서 Gompertz 모형이 가장 높은 적합도를 보였다. Logistic 모형은 모든 성별과 계통에서 모든 모형 중 가장 낮은 모형 적합도를 보였다. 성숙체중(α)의 경우 모든 성별과 계통에서 Von Bertalanffy, Gompertz, Logistic 모형 순으로 높게 나타났으며, 성장비(β)와 성숙률(γ)은 Logistic, Gompertz, Von Bertalanffy 모형 순으로 높게 나타났다. 성장곡선 모수인 α, β, γ는 암컷보다 수컷에서 높게 나타나는 경향을 보였다. 이 연구에서 수행한 가금연구소 보유 토종닭 순계 12계통의 육성기 성장 특성은 향후 토종닭 종계, 실용계를 생산하기 위한 교배조합 시험 설계와 순계의 개량방향, 그리고 사료 제한급이를 위한 기초자료로 활용될 것이다.

Receiver Operating Characteristic Analysis for Prediction of Postpartum Metabolic Diseases in Dairy Cows in an Organic Farm in Korea

  • Kim, Dohee;Choi, Woojae;Ro, Younghye;Hong, Leegon;Kim, Seongdae;Yoon, Ilsu;Choe, Eunhui;Kim, Danil
    • 한국임상수의학회지
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    • 제39권5호
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    • pp.199-206
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    • 2022
  • Postpartum diseases should be predicted to prevent productivity loss before calving especially in organic dairy farms. This study was aimed to investigate the incidence of postpartum metabolic diseases in an organic dairy farm in Korea, to confirm the association between diseases and prepartum blood biochemical parameters, and to evaluate the accuracy of these parameters with a receiver operating characteristic (ROC) analysis for identifying vulnerable cows. Data were collected from 58 Holstein cows (16 primiparous and 42 multiparous) having calved for 2 years on an organic farm. During a transition period from 4 weeks prepartum to 4 weeks postpartum, blood biochemistry was performed through blood collection every 2 weeks with a physical examination. Thirty-one (53.4%) cows (9 primiparous and 22 multiparous) were diagnosed with at least one postpartum disease. Each incidence was 27.6% for subclinical ketosis, 22.4% for subclinical hypocalcemia, 12.1% for retained placenta, 10.3% for displaced abomasum and 5.2% for clinical ketosis. Between at least one disease and no disease, there were significant differences in the prepartum levels of parameters like body condition score (BCS), non-esterified fatty acid (NEFA), total bilirubin (T-bil), direct bilirubin (D-bil) and NEFA to total cholesterol (T-chol) ratio (p < 0.05). The ROC analysis of each of these prepartum parameters had the area under the curve (AUC) <0.7. However, the ROC analysis with logistic regression including all these parameters revealed a higher AUC (0.769), sensitivity (71.0%), and specificity (77.8%). The ROC analysis with logistic regression including the prepartum BCS, NEFA, T-bil, D-bil, and NEFA to T-chol ratio can be used to identify cows that are vulnerable to postpartum diseases with moderate accuracy.

중환자실 환자의 건강결과 예측을 위한 중증도 평가도구의 정확도 비교분석 (Comparative Analysis of the Accuracy of Severity Scoring Systems for the Prediction of Healthcare Outcomes of Intensive Care Unit Patients)

  • 성지숙;소희영
    • 중환자간호학회지
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    • 제8권1호
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    • pp.71-79
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    • 2015
  • Purpose: The purpose of this study was to compare the applicability of the Charlson Comorbidity Index (CCI) and Acute Physiology, Age, Chronic Health Evaluation III (APACHE III) to the prediction of the healthcare outcomes of intensive care unit (ICU) patients. Methods: This research was performed with 136 adult patients (age>18 years) who were admitted to the ICU between May and June 2012. Data were measured using the CCI score with a comorbidity index of 19 and the APACHE III score on the standard of the worst result with vital signs and laboratory results. Discrimination was evaluated using receiver operating characteristic (ROC) curves and area under an ROC curve (AUC). Calibration was performed using logistic regression. Results: The overall mortality was 25.7%. The mean CCI and APACHE III scores for survivors were found to be significantly lower than those of non-survivors. The AUC was 0.835 for the APACHE III score and remained high, at 0.688, for the CCI score. The rate of concordance according to the CCI and the APACHE III score was 69.1%. Conclusion: The route of admission, days in ICU, CCI, and APACHE III score are associated with an increased mortality risk in ICU patients.

Lab-based Simulation of Carton Clamp Truck Handling - Frictional Characteristics between Corrugated Packages

  • Park, Jong Min;Choi, Sang Il;Kim, Jong Soon;Jung, Hyun Mo
    • 한국포장학회지
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    • 제25권3호
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    • pp.131-137
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    • 2019
  • Carton clamps, one of forklift attachments, allow users to quickly handle shipping units such as unitized loads, large shipping cases, or crates without the requirement of pallets. As the use of palletless handling by clamp trucks increases, so does the need for simulation research on clamp truck handling. The frictional characteristics for various contact conditions of corrugated paperboards and their constituent boards were analyzed to obtain the data needed in the computer simulation for the handling of carton clamp truck. The overall mean of static-frictional coefficients between selected corrugated paperboards was 0.38 (±0.01), which was 1.3~1.6 times greater than 0.23~0.29 of the frictional coefficients between boards. The overall mean of static-frictional coefficients between the corrugated paperboards and the rubber contact pad was 0.82 (±0.02), which was about 1.1 to 2.8 times greater than 0.29~0.78 of the static-frictional coefficient between the linerboard and the rubber contact pad. The overall mean of kinetic-frictional coefficients between the corrugated paperboards was 0.35 (±0.01), and 0.76 (±0.02) between the corrugated paperboards and the rubber contact pad.

Damage evolution of red-bed soft rock: Progressive change from meso-texture to macro-deformation

  • Guangjun Cui;Cuiying Zhou;Zhen Liu;Lihai Zhang
    • Geomechanics and Engineering
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    • 제36권2호
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    • pp.121-130
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    • 2024
  • Many foundation projects are built on red-bed soft rocks, and the damage evolution of this kind of rocks affects the safety of these projects. At present, there is insufficient research on the damage evolution of red-bed soft rocks, especially the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation. Therefore, based on the dual-porosity characteristics of pores and fissures in soft rock, we adopted a cellular automata model to simulate the propagation of these voids in soft rocks under an external load. Further, we established a macro-mesoscopic damage model of red-bed soft rocks, and its reliability was verified by tests. The results indicate that the relationship between the number and voids size conformed to a quartic polynomial, whereas the relationship between the damage variable and damage porosity conformed to a logistic curve. The damage porosity was affected by dual-porosity parameters such as the fractal dimension of pores and fissures. We verified the reliability of the model by comparing the test results with an established damage model. Our research results described the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation and provided a theoretical basis for the damage evolution of these rocks.

Selecting the Best Prediction Model for Readmission

  • Lee, Eun-Whan
    • Journal of Preventive Medicine and Public Health
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    • 제45권4호
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    • pp.259-266
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    • 2012
  • Objectives: This study aims to determine the risk factors predicting rehospitalization by comparing three models and selecting the most successful model. Methods: In order to predict the risk of rehospitalization within 28 days after discharge, 11 951 inpatients were recruited into this study between January and December 2009. Predictive models were constructed with three methods, logistic regression analysis, a decision tree, and a neural network, and the models were compared and evaluated in light of their misclassification rate, root asymptotic standard error, lift chart, and receiver operating characteristic curve. Results: The decision tree was selected as the final model. The risk of rehospitalization was higher when the length of stay (LOS) was less than 2 days, route of admission was through the out-patient department (OPD), medical department was in internal medicine, 10th revision of the International Classification of Diseases code was neoplasm, LOS was relatively shorter, and the frequency of OPD visit was greater. Conclusions: When a patient is to be discharged within 2 days, the appropriateness of discharge should be considered, with special concern of undiscovered complications and co-morbidities. In particular, if the patient is admitted through the OPD, any suspected disease should be appropriately examined and prompt outcomes of tests should be secured. Moreover, for patients of internal medicine practitioners, co-morbidity and complications caused by chronic illness should be given greater attention.

Diagnostic value of eosinopenia and neutrophil to lymphocyte ratio on early onset neonatal sepsis

  • Wilar, Rocky
    • Clinical and Experimental Pediatrics
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    • 제62권6호
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    • pp.217-223
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    • 2019
  • Purpose: To determine the diagnostic value of eosinopenia and the neutrophil-to-lymphocyte ratio (NLR) in the diagnosis of early onset neonatal sepsis (EONS). Methods: This cross-sectional study was conducted in the Neonatology Ward of R.D. Kandou General Hospital Manado between July and October 2017. Samples were obtained from all neonates meeting the inclusion criteria for EONS. Data were encoded using logistic regression analysis, the point-biserial correlation coefficient, chi-square test, and receiver operating characteristic curve analysis, with a P value <0.05 considered significant. Results: Of 120 neonates who met the inclusion criteria, 73 (60.8%) were males and 47 (39.2%) were females. Ninety (75%) were included in the sepsis group and 30 (25%) in the nonsepsis group. The mean eosinophil count in EONS and non-EONS groups was $169.8{\pm}197.1cells/mm^3$ and $405.7{\pm}288.9cells/mm^3$, respectively, with statistically significant difference (P<0.001). The diagnostic value of eosinopenia in the EONS group (cutoff point: $140cells/mm^3$) showed 60.0% sensitivity and 90.0% specificity. The mean NLR in EONS and non-EONS groups was $2.82{\pm}2.29$ and $0.82{\pm}0.32$, respectively, with statistically significant difference (P<0.001). The diagnostic value of NLR in the EONS group (cutoff point, 1.24) showed 83.3% sensitivity and 93.3% specificity. Conclusion: Eosinopenia has high specificity as a diagnostic marker for EONS and an increased NLR has high sensitivity and specificity as a diagnostic marker for EONS.

영상정보를 활용한 소셜 미디어상에서의 가짜 뉴스 탐지: 유튜브를 중심으로 (Fake News Detection on Social Media using Video Information: Focused on YouTube)

  • 장윤호;최병구
    • 한국정보시스템학회지:정보시스템연구
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    • 제32권2호
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    • pp.87-108
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    • 2023
  • Purpose The main purpose of this study is to improve fake news detection performance by using video information to overcome the limitations of extant text- and image-oriented studies that do not reflect the latest news consumption trend. Design/methodology/approach This study collected video clips and related information including news scripts, speakers' facial expression, and video metadata from YouTube to develop fake news detection model. Based on the collected data, seven combinations of related information (i.e. scripts, video metadata, facial expression, scripts and video metadata, scripts and facial expression, and scripts, video metadata, and facial expression) were used as an input for taining and evaluation. The input data was analyzed using six models such as support vector machine and deep neural network. The area under the curve(AUC) was used to evaluate the performance of classification model. Findings The results showed that the ACU and accuracy values of three features combination (scripts, video metadata, and facial expression) were the highest in logistic regression, naïve bayes, and deep neural network models. This result implied that the fake news detection could be improved by using video information(video metadata and facial expression). Sample size of this study was relatively small. The generalizablity of the results would be enhanced with a larger sample size.

머신러닝을 활용한 코스닥 관리종목지정 예측 (Predicting Administrative Issue Designation in KOSDAQ Market Using Machine Learning Techniques)

  • 채승일;이동주
    • 아태비즈니스연구
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    • 제13권2호
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    • pp.107-122
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    • 2022
  • Purpose - This study aims to develop machine learning models to predict administrative issue designation in KOSDAQ Market using financial data. Design/methodology/approach - Employing four classification techniques including logistic regression, support vector machine, random forest, and gradient boosting to a matched sample of five hundred and thirty-six firms over an eight-year period, the authors develop prediction models and explore the practicality of the models. Findings - The resulting four binary selection models reveal overall satisfactory classification performance in terms of various measures including AUC (area under the receiver operating characteristic curve), accuracy, F1-score, and top quartile lift, while the ensemble models (random forest and gradienct boosting) outperform the others in terms of most measures. Research implications or Originality - Although the assessment of administrative issue potential of firms is critical information to investors and financial institutions, detailed empirical investigation has lagged behind. The current research fills this gap in the literature by proposing parsimonious prediction models based on a few financial variables and validating the applicability of the models.

Comparative Study of Contrast-Enhanced Ultrasound Qualitative and Quantitative Analysis for Identifying Benign and Malignant Breast Tumor Lumps

  • Liu, Jian;Gao, Yun-Hua;Li, Ding-Dong;Gao, Yan-Chun;Hou, Ling-Mi;Xie, Ting
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8149-8153
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    • 2014
  • Background: To compare the value of contrast-enhanced ultrasound (CEUS) qualitative and quantitative analysis in the identification of breast tumor lumps. Materials and Methods: Qualitative and quantitative indicators of CEUS for 73 cases of breast tumor lumps were retrospectively analyzed by univariate and multivariate approaches. Logistic regression was applied and ROC curves were drawn for evaluation and comparison. Results: The CEUS qualitative indicator-generated regression equation contained three indicators, namely enhanced homogeneity, diameter line expansion and peak intensity grading, which demonstrated prediction accuracy for benign and malignant breast tumor lumps of 91.8%; the quantitative indicator-generated regression equation only contained one indicator, namely the relative peak intensity, and its prediction accuracy was 61.5%. The corresponding areas under the ROC curve for qualitative and quantitative analyses were 91.3% and 75.7%, respectively, which exhibited a statistically significant difference by the Z test (P<0.05). Conclusions: The ability of CEUS qualitative analysis to identify breast tumor lumps is better than with quantitative analysis.