• Title/Summary/Keyword: logistic curve

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Estimation of Growth Curves and Suitable Slaughter Weight of the Liangshan Pig

  • Luo, Jia;Lei, Huaigang;Shen, Linyuan;Yang, Runlin;Pu, Qiang;Zhu, Kangping;Li, Mingzhou;Tang, Guoqing;Li, Xuewei;Zhang, Shunhua;Zhu, Li
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.9
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    • pp.1252-1258
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    • 2015
  • The Liangshan pig is a traditional Chinese small-sized breed; it has a relatively long feeding period and low meat production ability but superior meat quality. This study utilized three non-linear growth models (Von Bertalanffy, Gompertz, and logistic) to fit the growth curve of Liangshan pigs from an unselected, random-bred pig population and estimate the pigs most suitable slaughter weight. The growth development data at 20 time points of 275 Liangshan pigs (from birth to 250 d) were collected. To analyze the relative gene expression related to development, seven slaughter weight phases (50, 58, 66, 74, 82, 90, and 98 kg) (20 pigs per phase) were examined. We found that the Liangshan pig growth curve fit the typical S-curve well and that their growth turning point was 193.4 days at a weight of 62.5 kg, according to the best fit Von Bertalanffy model based on the goodness of fit criteria. Furthermore, we estimated that the most suitable slaughter weight was 62.5 to 74.9 kg based on the growth curve and the relative expression levels of growth-related genes.

A Study on the Selectivity of the Trawl Net for the Demersal Fishes in the East China Sea-III (동지나해 저서 어자원에 대한 트롤어구의 어획선택성에 관한 연구-III)

  • Lee, Ju-Hee;Kim, Sam-Gon;Kim, Min-Seok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.29 no.3
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    • pp.177-182
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    • 1993
  • In order to estimate the mesh selectivity master curves and the optimum mesh size, experiments were made by the cover net method with the cod-ends of the five different the opening mesh sizes(51.2mm, 70.2mm, 77.6mm, 88.0mm and 111.3mm). After that 163 hauling were performed and there by investigated, on the training vessel Saebada in the Southern Korean Sea and East China Sea from June 1991 to August 1992. In this report, the mesh selectivity master curves were fitted by using logistic function(S=1/(1+exp super(-(aR+b))), R=(L-L sub(0))/(M-M sub(0)) and the optimum mesh sizes were estimated from each master curve. In this case, a and b are the selection parameters, M is the mesh size of each experimental cod-end. L is body length, L sub(0) and M sub(0) is the distance from the coordinate origine to intersection of linear regression between 25% and 50% selection length. The results obtained are summarized as follows; 1. Trachurus japonicus: Mesh selectivity master curve parameters: a and b were 2. 25, -4.73 respectively and optimum mesh size was estimated to be 79.3mm. 2. Trichiurus lepturus: Mesh selectivity master curve parameters: a and b were 0.81, -3.17 respectively and optimum mesh size was estimated to be 64.5mm. 3. Photololigo edulis: Mesh selectivity master curve parameters: a and b were 1.30m, -4.10 respectively and optimum mesh size was estimated to be 89.9mm. 4. Todarodes pacificus: Mesh selectivity master curve parameters: a and b were 1. 35, -3.45 respectively and optimum mesh size was estimated to be 89.4mm.

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Tooth selectivity on venus clam (Gomphina melanaegis) dredge (민들조개 (Gomphina melanaegis) 형망의 갈퀴에 의한 어획선택성)

  • 박해훈;김승환
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.36 no.4
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    • pp.267-273
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    • 2000
  • The tooth selectivity of the dredge for catching venus clam (Gomphina melanaegis) was described in which the teeth penetrated the bottom and lifted the shell into the bag. Some factors affecting the selection action of the teeth of the dredge were analyzed related to shell length and shell height. The retention probability of venus clam not sifting through the gaps between the teeth was calculated for various shell lengths and was fitted to two parameter logistic selection curve. The formula obtained is as follows: $P= \frac{1}{1+exp[8.24](\frac{d}{L_1}-0.649)}$, where d is distance between teeth and $L_1$ is a shell length. For biological minimum size(25mm) of venus clam to be catchability 50% the distance between teeth was estimated 16.2mm from the logistic curve. Therefore it is desirable to extend that current spacing between teeth from 12mm to 16mm for the venus clam dredge. That space increasing enables fuel oil of vessel to drag a dredge to be reduced and also man power to sift through sifter smaller venus clams on boards to be reduced.

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Build the nomogram by risk factors of chronic obstructive pulmonary disease (COPD) (만성 폐쇄성 폐질환의 위험요인 선별을 통한 노모그램 구축)

  • Seo, Ju-Hyun;Oh, Dong-Yep;Park, Yong-Soo;Lee, Jea-Young
    • The Korean Journal of Applied Statistics
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    • v.30 no.4
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    • pp.591-602
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    • 2017
  • The concentration of fine dust has increased in Korea and people have become more concerned with respiratory diseases. This study selected risk factors for chronic obstructive pulmonary disease (COPD) through demographic and clinical features and constructed a nomogram. First, logistic regression analysis was performed using demographic and clinical feature and the pulmonary function test results of the Korean National Health and Nutrition Examination Survey (KNHANES) $6^{th}$ (2013-2015) and the nomogram was constructed to visualize the risk factors of chronic obstructive pulmonary disease in order to facilitate the interpretation of the analysis results. The ROC curve and calibration plot were also used to verify the nomogram of chronic obstructive pulmonary disease.

An experimental study on the size selectivity of fusiform fish by the netting characteristics (망지 특성에 따른 방추형 어류의 크기 선택성에 대한 실험적 연구)

  • Sena BAEK;Hyungseok KIM;Kyung-Jin RYU;Seonghun KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.3
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    • pp.189-195
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    • 2023
  • This study quantitatively evaluated size selectivity for three netting shapes (T0; regular, T45, T90) and hanging ratio (35%, 70%) of T0 netting used for trawl codend. The size selectivity experiment was performed in a tank using a cube experimental model with a length of 50 cm on one side and 389 experimental individuals, jack mackerel (Trachurus japonicus). In the selectivity analysis, a selectivity curve was created based on the selection ratio using a logistic function, and the 25%, 50%, and 70% selection length and selection range (SR) were obtained. The T0 netting was 19.54 cm when the 50% selective length, which is a selectivity evaluation index, had a hanging ratio of 35%, a selection range of 0.51 cm, and 22.70 cm and 3.08 cm for the hanging ratio of 70%. The T45 netting was 24.34 cm and 2.13 cm, and the T90 netting was 23.51 cm and 2.84 cm. The results of the T45 netting and the T90 netting are similar, and the 50% selection length and selection range were relatively larger than the T0 netting. There was a significant difference in the correlation between the circumference of the inner circle of the mesh by the shape of the netting and the body girth of the experimental individual (Pearson test, r = 0.86, p < 0.05). There was no significant difference in the correlation between the selection ratio by the T0 netting, T45 netting, and T90 netting with a 70% hanging ratio (one-way ANOVA, p > 0.05). The results of this study showed that selectivity such as T45 netting and T90 netting appeared when the hanging ratio, which maximizes the area of T0 netting, was maintained at 70%.

Susceptibility Mapping of Umyeonsan Using Logistic Regression (LR) Model and Post-validation through Field Investigation (로지스틱 회귀 모델을 이용한 우면산 산사태 취약성도 제작 및 현장조사를 통한 사후검증)

  • Lee, Sunmin;Lee, Moung-Jin
    • Korean Journal of Remote Sensing
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    • v.33 no.6_2
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    • pp.1047-1060
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    • 2017
  • In recent years, global warming has been continuing and abnormal weather phenomena are occurring frequently. Especially in the 21st century, the intensity and frequency of hydrological disasters are increasing due to the regional trend of water. Since the damage caused by disasters in urban areas is likely to be extreme, it is necessary to prepare a landslide susceptibility maps to predict and prepare the future damage. Therefore, in this study, we analyzed the landslide vulnerability using the logistic model and assessed the management plan after the landslide through the field survey. The landslide area was extracted from aerial photographs and interpretation of the field survey data at the time of the landslides by local government. Landslide-related factors were extracted topographical maps generated from aerial photographs and forest map. Logistic regression (LR) model has been used to identify areas where landslides are likely to occur in geographic information systems (GIS). A landslide susceptibility map was constructed by applying a LR model to a spatial database constructed through a total of 13 factors affecting landslides. The validation accuracy of 77.79% was derived by using the receiver operating characteristic (ROC) curve for the logistic model. In addition, a field investigation was performed to validate how landslides were managed after the landslide. The results of this study can provide a scientific basis for urban governments for policy recommendations on urban landslide management.

Mortality and Morbidity of Aneurysmal Neck Clipping during the Learning Curve

  • Lee, Sang-Ho;Hwang, Hyung-Sik;Moon, Seung-Myung;Kim, Sung-Min;Choi, Sun-Kil
    • Journal of Korean Neurosurgical Society
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    • v.40 no.1
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    • pp.16-21
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    • 2006
  • Objective : Young neurosurgeons need to focus on the mortality and morbidity of aneurysmal neck clipping to develop a personal experience with an initial series. Methods : Total 88 aneurysms from 75 patients who underwent neck clipping by the same operator from 2001 to 2004 were reviewed. Patients were divided into three groups : first year [Group I], second year [Group II], and third year [Group III] in each group. Location of aneurysm, age, Fisher grade, Hunter-Hess grade [H-H grade], postoperative Glasgow outcome scale [GOS], and complications related to surgical procedures were evaluated with Chi-square and logistic regression analyses. Results : Fourteen patients had complications related to surgery [18.7%]. The major causes of mortality and morbidity related to surgery were cerebral infarction, hemorrhage and brain swelling due to intraoperative rupture, brain retraction and vasospasm. Among the 4 cases of mortality were 2 patients in Group I, 1 patient in Group II and 1 patient in Group III, and location of aneurysms were 2 internal carotid artery[ICA] and 2 posterior communicating artery[PCoA] aneurysms. There were 4 morbidity and new neurological deficits in Group I, 4 in Group II and 2 in Group III. Although mortality and morbidity during the learning curve had a statistical significance in H-H grade, age [>60 years old], and aneurysm location [especially ICA aneurysm] as variables, mortality mainly occurred in ICA and PCoA aneurysms. Conclusion : Experienced supervision or endovascular approach should be considered for the treatment of ICA and PCoA aneurysms during the learning curve.

Perceptual Boundary on a Synthesized Korean Vowel /o/-/u/ Continuum by Chinese Learners of Korean Language (/오/-/우/ 합성모음 연속체에 대한 중국인 한국어 학습자의 청지각적 경계)

  • Yun, Jihyeon;Kim, EunKyung;Seong, Cheoljae
    • Phonetics and Speech Sciences
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    • v.7 no.4
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    • pp.111-121
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    • 2015
  • The present study examines the auditory boundary between Korean /o/ and /u/ on a synthesized vowel continuum by Chinese learners of Korean language. Preceding researches reported that the Chinese learners have difficulty pronouncing Korean monophthongs /o/ and /u/. In this experiment, a nine-step continuum was resynthesized using Praat from a vowel token from a recording of a male announcer who produced it in isolated form. F1 and F2 were synchronously shifted in equal steps in qtone (quarter tone), while F3 and F4 values were held constant for the entire stimuli. A forced choice identification task was performed by the advanced learners who speak Mandarin Chinese as their native language. Their experiment data were compared to a Korean native group. ROC (Receiver Operating Characteristic) analysis and logistic regression were performed to estimate the perceptual boundary. The result indicated the learner group has a different auditory criterion on the continuum from the Korean native group. This suggests that more importance should be placed on hearing and listening training in order to acquire the phoneme categories of the two vowels.

Railway Noise Exposure-response Model based on Predicted Noise Level and Survey Results (예측소음도와 설문결과를 이용한 철도소음 노출-반응 모델)

  • Son, Jin-Hee;Lee, Kun;Chang, Seo-Il
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.5
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    • pp.400-407
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    • 2011
  • The suggested method of previous Son's study dichotomized subjective response data to modeling noise exposure-response. The method used maximum liklihood estimation instead of least square estimation and the noise exposure-response curve of the study was logistic regression analysis result. The method was originated to modeling community response rate such as %HA or %A. It can be useful when the subjective response was investigated based on predicted noise level. It is difficult to measure the single source emitting noise such as railway because various traffic noise sources combined in our life. The suggested method was adopted to model in this study and railway noise-exposure response curves were modeled because the noise level of this area was predicted data. The data of this study was used by previous Ko's paper but he dealt the area as combined noise area and divided the data by dominant noise source. But this study used all data of this area because the annoyance response to railway noise was higher than other noise according to the result of correlation analysis. The trend of the %HA and %A prediction model to train noise of this study is almost same as the model based on measured noise of previous Lim's study although the investigated areas and methods were different.

The Relation between Verbal Aggression by Parents and Children's Maladjusted Emotional Behavior (부모의 언어적 학대와 아동의 정서적 부적응행동과의 관계)

  • Kim, Hye Ryun;Lee, Jae Yeon
    • Korean Journal of Child Studies
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    • v.15 no.1
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    • pp.91-108
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    • 1994
  • This study investigated the relation between verbal abuse by parents and children's maladjusted emotional behavior. The sampling consisted of 628 children in 16 classes out of every three elementary schools and one middle school. Instruments used for this study were the Verbal Abuse Measure, Parent-to-child violence items of the Conflict Tactics Scales, Emotional Maladjustment Behavior Scale, and Socioeconmic Status. Methods applied to data analysis were multiple regression, logistic regression and logistic curve graphic display. The major findings were ; (1) Of all subjects, almost 20% experienced at least one instance in which they were victims of verbal abuse during the year covered by this study. (2) As the amount of physical abuse by parents increased the verbal abuse by parents increased. The older children experienced more verbal abuse than the younger ones. (3) Verbal abuse by parents was more highly related to maladjusted emotional behavior of the children than physical abuse by parents. (4) Regardless of the physical violence by parents, verbal abuse by parents was associated with maladjusted emotional behavior of children. Children who were subjected to both verbal and physical abuse were more strongly related to withdrawal, hyperactivity, and obsessive-compulsions than children experienced either one or the other.

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