• Journal of fish pathology
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• v.26 no.2
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• pp.65-75
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• 2013

Population growth equation of scuticociliate Miamiensis avidus was obtained from the experimental results of in vitro culture condition to estimate the growth rate and carrying capacity from the growth equation. In addition, intraperitoneal infections into olive flounder Paralichthys olivaceus were carried out into 2 different conditions: different concentrations of M. avidus in same water temperature and same concentration of M. avidus in different water temperatures. Olive flounder mortality was threshold dependent with both the temperature and M. avidus density parameters. In this paper, we propose a mathematical model to study M. avidus growth in olive flounder based upon the interactions between parasite and host. The mathematical model was logistic growth differential equation (1.2). The parameters were found with Matlab program through the Levenberge-Marquardt method. In theorem, equilibrium values between the infected fish population and dead population could found. Our equilibrium points were a stable equilibrium and an unstable equilibrium. From the equation (1.6), it was possible to predict the amount of cumulative mortality of olive flounder along with the time after M. avidus infection.

• Journal of Korean Academy of Nursing
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• v.27 no.4
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• pp.796-806
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• 1997

The majority of studies on breastfeeding consists of descriptive correlational studies identifying the incidence and correlates of breastfeeding. The theory of planned behavior has been shown to yield great predictive power for behavioral goals over which individuals have only limited control such as improving school grades and weight loss. The purpose of this study was to test the "theory of planned behavior" in the prediction of breastfeeding of mothers who delivered vaginally, One hundred mothers who delivered vaginally in one general hospital in Seoul and one general hospital and three private hospitals in Taejeon participated in this study. The instruments used for data collection in this study were developed by the researchers following the guidelines suggested by Ajzen & Fishbein(1980) and Ajzen & Madden(1986). The instruments included measurement of attitude, subjective norm, perceived behavioral control and intention. The collected data were analyzed using descriptive statistics, Pearson product moment correlation, hierachical multiple regression and logistic regression. The results are as follows ; 1. Intention to breastfeed correlated significantly with attitude, subjective norm and perceived behavioral control. Both attitude and subjective norm did not make a significant contribution to the prediction of intention, but the addition of perceived behavioral control to the regression equation greatly improved the model's predictive power, increasing the R²from .05 to .52. 2. Intention to breastfeed alone had a significant predictive effect on actual breastfeeding, resulting in a regression coefficient of .16(X²=8 60, p<.01), but when perceived behavioral control was added to the equation, intention was not a significant predictive variable and only perceived behavioral control showed significant predictive power on actual breastfeeding, resulting in a regression coefficient of .12(X²=4.69, p<.05). In sum, breastfeeding behavior lent only partial support to the second version of the theory of planned behavior, and because perceived behavioral control had a strong effect on intention to breastfeed and actual breastfeeding, It would be desirable to develop nursing intervention programs which focus on strengthening the perceived behavioral control for the promotion of breastfeeding.

• Journal of Preventive Medicine and Public Health
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• v.51 no.3
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• pp.154-162
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• 2018

Objectives: Early retirement occurs when one's job satisfaction suffers due to employment mismatch resulting from factors such as inadequate compensation. Medical doctors report high levels of job stress and burnout relative to other professionals. These levels are highest among emergency physicians (EPs), and despite general improvements in their working conditions, early retirement continues to become more common in this population. The purpose of this study was to identify the factors influencing EPs intention to retire early and to develop a probability equation for its prediction. Methods: A secondary analysis of data from the 2015 Korean Society of Emergency Physicians Survey was performed. The variables potentially influencing early retirement were organized into personal characteristics, extrinsic factors, and intrinsic factors. Logistic regression analysis was performed to identify risk factors and to develop a probability equation; these findings were then arranged in a nomogram. Results: Of the 377 survey respondents included in the analysis, 48.0% intended to retire early. Risk factors for early retirement included level of satisfaction with the specialty and its outlook, slanderous reviews, emergency room safety, health status, workload intensity, age, and hospital type. Intrinsic factors (i.e., slanderous reviews and satisfaction with the specialty and its outlook) had a stronger influence on early retirement than did extrinsic factors. Conclusions: To promote career longevity among EPs, it is vital to improve emergency room safety and workload intensity, to enhance medical professionalism through a stronger vision of emergency medicine, and to strengthen the patient-doctor relationship.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.302-308
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• 1998

The growth of the purple sea urchin, Anthocidaris crassispina, has been investigated using reproduction plates as a chararter of the age determination. The samples were collected on the coast of Daepo, in the southern part of Cheju Island from August, 1995 to July, 1996. Monthly growth of test diameter mainly occurred from December to March. The obvious growth, however, were not observed between April and June which seemed to be the resting period. This resting period well corresponded to the time of annual ring formation which was estimated from the analysis of the marginal growth rate. The growth curve fitted well with Bertalanffy equation: $$L_t=46.65 (1-e^{-0.283(t+9.210)}),\;W_t=44.90 (1-e^{-0.283(t+9.210)})^3$$

• Health Policy and Management
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• v.31 no.4
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• pp.451-461
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• 2021

Background: Readmissions related to lack of quality care harm both patients and health insurance finances. If the factors affecting readmission are identified, the readmission can be managed by controlling those factors. This paper aims to identify factors that affect readmissions of convalescent rehabilitation patients. Methods: Health Insurance Review and Assessment Service claims data were used to identify readmissions of convalescent patients who were admitted in hospitals and long-term care hospitals nationwide in 2018. Based on prior research, the socio-demographics, clinical, medical institution, and staffing levels characteristics were included in the research model as independent variables. Readmissions for convalescent rehabilitation treatment within 30 days after discharge were analyzed using logistic regression and generalization estimation equation. Results: The average readmission rate of the study subjects was 24.4%, and the risk of readmission decreases as age, length of stay, and the number of patients per physical therapist increase. In the patient group, the risk of readmission is lower in the spinal cord injury group and the musculoskeletal system group than in the brain injury group. The risk of readmission increases as the severity of patients and the number of patients per rehabilitation medicine specialist increases. Besides, the readmission risk is higher in men than women and long-term care hospitals than hospitals. Conclusion: "Reducing the readmission rate" is consistent with the ultimate goal of the convalescent rehabilitation system. Thus, it is necessary to prepare a mechanism for policy management of readmission.

• Health Policy and Management
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• v.27 no.2
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• pp.128-138
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• 2017

Background: The purpose of this study is to analyze the effects of differential coinsurance policy on prescription drug coverage of outpatients by types of medical institutions. Methods: In this study, we used a sample cohort database of the National Health Insurance Service and frequency analysis and marginal logistic regression model using generalized estimating equation were used for statistical analysis. Results: The summary on the major research is followed. First, about 16% of patients who used only tertiary or general hospital due to 52 ambulatory care sensitive conditions before policy implementation moved to hospitals and clinics. However, about 57% of them still use tertiary or general hospital. Second, the factors influencing the utilization of hospitals and clinics after the implementation of the policy were gender, age, and income level. As a result, the policy is effective to reduce the medical use of outpatient mental patients in tertiary or general hospital, but the effect is not significant. Conclusion: Therefore, in order to achieve the purpose of the policy for establishing the health care delivery system, it is necessary to adjust the co-payment so as to feel the burden on the co-payment when the outpatient for 52 ambulatory care sensitive conditions is used at the tertiary or general hospital.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.3
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• pp.193-201
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• 2020

The mesh selectivity of a drum shaped pot for finely-striate buccinum (Buccinum striatissimum) was conducted a total of eight times with four different mesh sizes (22, 35, 50 and 60 mm) from May to September, 2019 in the eastern coastal waters of Korea. The size selectivity analysis was estimated by the SELECT method to express logistic selectivity curves. In the results, the catch of finely-striate buccinum was occupied about 90% in the total catch weight. The equation of the master curve of selectivity was estimated to s(R) = exp(-7.778R+9.983)/[1+exp(-7.778R+9.983)]. The relative shell height of 50% selection was 1.284 and the selection range (SR) was 0.282. The optimal mesh size for 50% selection on the minimum maturation size (75 mm, Shell height) was estimated more than 60 mm by the master selectivity curve.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.89-95
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• 2018

The maturation and spawning of black scraper, Thamnaconus modestus were studied using samples collected monthly from March, 2015 to February, 2016 in the coastal waters off Middle East Sea, Korea. The gonadosomatic index (GSI) of female was the highest in June. The spawning periods lasted from March to September based on histological observation of female gonad development. The percentage of sexually mature females estimated from a logistic function was over 50% for the size group 18.02 cm (total length, TL). The size of eggs spawned was between 0.40 to 0.58 mm. Fecundity varied between 185,648 and 9,747,250 eggs. The relationship between the fecundity and TL of the fish was expressed in the fecundity equation as $F=0.0297TL^{5.4835}$.

• Communications for Statistical Applications and Methods
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• v.15 no.5
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• pp.687-695
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• 2008

It is widely known that the home advantage plays an important factor for determining victory or defeat in sport leagues. Thus a ranking system of sport league should take account of the home advantage as a key factor. Various statistical models are studied to rate the Korean Basketball league teams in 2006-2007 season. Among them, the model equation provided by Harville and Smith (1994) is useful for constructing two ranking systems. Both systems give quite reasonable quantifications of the team's ability and the home advantage.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2209-2211
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• 2004

Unlike the wavelet neural network, since a mother wavelet layer of the self-recurrent wavelet neural network (SRWNN) is composed of self-feedback neurons, it has the ability to store past information of the wavelet. Therefore we propose the prediction method for the nonlinear chaotic time series model using a SRWNN. The SRWNN model is learned for the modeling of a function such that the inputs arc known values of the time series and the output is the value in the future. The parameters of the network are tuned to minimize the difference between the nonlinear mapping of the chaotic time series and the output of SRWNN using the gradient-descent method for the adaptive backpropagation algorithm. Through the computer simulations, we demonstrate the feasibility and the effectiveness of our method for the prediction of the logistic map and the Mackey-Glass delay-differential equation as a nonlinear chaotic time series.