• 보건행정학회지
• /
• 제14권2호
• /
• pp.78-98
• /
• 2004

The purpose of this study was to categorize the contribution evasion and develop the expected models for contribution arrears in National Health Care System. The modified logistic regression model in non-payments was used as logistic regression model based on the statistical method. By using this model, we arranged non-payment types and typical branches those are appeared by statistical technique. First fact, sex and age branches those are able to take a part in economy had effect mostly. Also they had difference in non-payment probability by existence of their incomes and property. Especially people who didn't have their own house and car were appeared in high non-payment probability, disease and reduction characteristic(rare diseases, reduction of seniors, handicaps, numbers of medical treatments) didn't effect much in probability. The reason for some characteristic of non-payment which is higher than the correct threshold value of Logistic Regression Model (a suggested model for predicting non-payment)'s distribution of probability was mostly moral hazard. Living difficulty was the bigger reason for non-payment, but moral slackening was the bigger reason for non-payment. But it is careless to decide that moral hazard is just the reason, there is a necessity to examine on the side of sociology based in family. By the reason, the member's non-payment reason can be classified by economy, population, and psychology, but there was a comprehension that losing of work desire could be one reason. So we analyzed informations for composition of family of members. In conclusion, we grasped that family conflict makes non-payment and conversion of member in the National Basic Livelihood Protection System difficult.

• Journal of Korean Neurosurgical Society
• /
• 제67권2호
• /
• pp.177-185
• /
• 2024

Objective : Delayed cerebral ischemia (DCI) is a major cause of disability in patients who survive aneurysmal subarachnoid hemorrhage (aSAH). Systemic inflammatory markers, such as peripheral leukocyte count and systemic immune-inflammatory index (SII) score, have been considered predictors of DCI in previous studies. This study aims to investigate which systemic biomarkers are significant predictors of DCI. Methods : We conducted a retrospective, observational, single-center study of 170 patients with SAH admitted between May 2018 and March 2022. We analyzed the patients' clinical and laboratory parameters within 1 hour and 3-4 and 5-7 days after admission. The DCI and non-DCI groups were compared. Variables showing statistical significance in the univariate logistic analysis (p<0.05) were entered into a multivariate regression model. Results : Hunt-Hess grade "4-5" at admission, modified Fisher scale grade "3-4" at admission, hydrocephalus, intraventricular hemorrhage, and infection showed statistical significance (p<0.05) on a univariate logistic regression. Lymphocyte and monocyte count at admission, SII scores and C-reactive protein levels on days 3-4, and leukocyte and neutrophil counts on days 5-7 exhibited statistical significance on the univariate logistic regression. Multivariate logistic regression analysis revealed that monocyte count at admission (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.04-2.65; p=0.036) and SII score at days 3-4 (OR, 1.55; 95% CI, 1.02-2.47; p=0.049) were independent predictors of DCI. Conclusion : Monocyte count at admission and SII score 3-4 days after rupture are independent predictors of clinical deterioration caused by DCI after aSAH. Peripheral monocytosis may be the primer for the innate immune reaction, and the SII score at days 3-4 can promptly represent the propagated systemic immune reaction toward DCI.

• 응용통계연구
• /
• 제15권2호
• /
• pp.323-336
• /
• 2002

최근에 1상 임상실험 에서 사용되는 continual reassessment method (CRM)에 대한 연구가 활발히 이루어지고 있다. 본 논문에서는 세 명의 환자를 하나의 환자 군으로 삼아 동일한 용량을 투여하는 수정된 CRM에 대한 연구를 실행하였다. 지금까지 CRM에 대한연구는 대부분 시뮬레이션에 의존하여 왔지만, 본 논문에서는 모든 가능한 경우를 고려하는 방법(complete enumeration)을 사용하였다. 이 새로운 방법은 시뮬레이션을 대체할 유용한 방법이라 사료된다. 이 새로운 방법을 이용하여, 용량독성곡선이 logistic함수, hyperbolic tangent 함수, power 함수일 때, 수정된 CRM에서 결정한 최대허용용량에서의 독성 확률이 목표 독성 확률로 잘 수렴함을 보였다. 하지만, 실험 전에 용량들을 적절히 선택하지 못하면, 최대허용용량에서의 독성 확률이 목표 독성 확률과 상당한 차이를 낼 수도 있음을 발견하였다.

• 정보관리연구
• /
• 제37권1호
• /
• pp.1-16
• /
• 2006

인터넷이 빠르게 확산됨에 따라서 기존의 통신 서비스 시장이 급격하게 변화하고 있어서 음성 중심의 통신 서비스에서 데이터 중심의 통신 서비스로 이행되고 있다. 이 과정에서 대표적인 정보 통신 서비스인 유선전화, 휴대전화, 인터넷 서비스는 서로 영향을 주고받으며 성장하고 있다. 본 연구는 유선전화, 휴대전화와 인터넷의 확산과정을 기술들의 상호관계를 고려하여 여러 국가의 사례를 통해서 분석해 보고자 한다. 이를 위해 1975년부터 2002년까지의 국가별 시계열 자료(time series data)를 이용하여 수정된 로지스틱 성장모형(modified logistic growth model)을 통해 통신 기술의 확산과정을 살펴본다. 이를 통해서 통신기술 간의 상호관계가 국가적으로 어떤 형태를 보이고 있는 지 확인할 수 있을 것이다. 또한, 본 연구는 기존 통신 서비스의 확산과정을 토대로 신규 통신 서비스가 출현했을 때의 수요예측에 필요한 핵심적인 정보를 도출하며, 인프라 투자의 비중이 높은 네트워크 산업의 시장진출 전략에 함의를 제공할 것이다.

• 한국통신학회논문지
• /
• 제25권1B호
• /
• pp.99-104
• /
• 2000

본 논문은에서는 저작권 보호를 위한 디지털 워터마크 삽입방법에서 워터마크로 많이 사용하는 정규 가우시안 시퀀스를 카오스 시퀀스로 대체하고 그 성능을 비교하여 분석한다. 카오스 시퀀스는 만들기가 쉽고, 초기 치의 변화에 따라 전혀 다른 시퀀스를 만들 수 있다. 본 논문에서 사용한 카오스 시퀀스는 Chebyshev map의 시퀀스 분포를 갖도록 Logistic map을 수정하였다. 실험방법은 원 영상을 웨이브릿 변환하여 카오스 시퀀스와 가우시안 시퀀스로 워터마킹한 후 여러 가지 영상처리와, 반복적인 실험의 결과로 나타난 유사도의 분포를 측정, 비교하였다. DCT-기반 워터마킹 시스템의 결과와 마찬가지로 카오스 시퀀스는 일반적인 신호처리에 있어서 가우시안 시퀀스 못지 않게 강하다. 또한 연속적인 반복 실험에 의한 유사도 편차가 가우시안의 경우보다 작고, 손실 압축에 있어서는 가우시안 시퀀스 보다 좋은 성능을 보였다.

• Smart Structures and Systems
• /
• 제24권3호
• /
• pp.361-377
• /
• 2019

The stiffness of shape memory alloy (SMA) spring while in actuation is represented by an empirical model that is derived from the logistic differential equation. This model correlates the stiffness to the alloy temperature and the functionality of SMA spring as active variable stiffness actuator (VSA) is analyzed based on factors that are the input conditions (activation current, duty cycle and excitation frequency) and operating conditions (pre-stress and mechanical connection). The model parameters are estimated by adopting the nonlinear least square method, henceforth, the model is validated experimentally. The average correlation factor of 0.95 between the model response and experimental results validates the proposed model. In furtherance, the justification is augmented from the comparison with existing stiffness models (logistic curve model and polynomial model). The important distinction from several observations regarding the comparison of the model prediction with the experimental states that it is more superior, flexible and adaptable than the existing. The nature of stiffness variation in the SMA spring is assessed also from the Dynamic Mechanical Thermal Analysis (DMTA), which as well proves the proposal. This model advances the ability to use SMA integrated mechanism for enhanced variable stiffness actuation. The investigation proves that the stiffness of SMA spring may be altered under controlled conditions.

• 농업과학연구
• /
• 제48권4호
• /
• pp.987-1001
• /
• 2021

One of the most critical issues in the dairy industry, alongside the low birth rate and the aging population, is the decrease in demand for milk. In this study, the consumption trends of 12 major dairy products distributed in Korea were predicted using a logistic model, the Gompertz model, and the Bass diffusion model, which are representative S-shaped growth models. The 12 dairy products are fermented milk (liquid type, cream type), butter, milk powder (modified, whole, skim), liquid milk (market, flavored), condensed milk, cheese (natural, processed), and cream. As a result of the analysis, the growth potential of butter, condensed milk, natural cheese, processed cheese, and cream consumption among the 12 dairy products is relatively high, whereas the growth of the remaining dairy product consumption is expected to stagnate or decrease. However, butter and cream are by-products of the skim milk powder manufacturing process. Therefore, even if the consumption of butter and cream grows, it is difficult to increase the demand of domestic milk unless the production of skim milk powder produced from domestic milk is also increased. Therefore, in order to support the domestic dairy industry, policy support should be focused on increasing domestic milk usage for the production of condensed milk, natural cheese, and processed cheese.

• Journal of the Korean Data and Information Science Society
• /
• 제26권6호
• /
• pp.1305-1315
• /
• 2015

ROC 곡선을 구성하는 한 개의 스코어 변수로 이루어진 분류모형을 확장하여 선형 스코어의 함수인 리스크 스코어를 고려하고, 선형 스코어의 계수를 추정하기 위한 방법으로 AUC를 최대화하는 방법을 사용한다. 이런 AUC 접근방법으로 구한 스코어의 계수 추정량은 로지스틱모형을 이용한 선형 스코어의 모수의 최대가능도 추정량보다 자료가 로지스틱 가정이 맞지 않는 일반적인 상황에서도 좋은 추정 결과를 보인다. 본 연구에서는 다항범주로 분류되어 현실적인 판별 및 예측 상황을 고려하여 AUC 접근방법을 확장한 VUS와 HUM 접근방법을 제안한다. 연결함수로는 로짓, complementary log-log와 로짓을 변형한 함수의 세 종류와 그리고 다양한 분류점의 분포인 경우에 대하여도 모의실험을 실시하였다. 본 논문에서는 다항범주 판별결과에 대하여 VUS와 HUM 접근방법도 AUC 접근방법과 유사하게 다양한 연결함수에 대하여 로지스틱모형 추정방법보다 동등하거나 더 나은 모수추정 결과를 보이는 것을 확인하였다.

• Animal Bioscience
• /
• 제35권5호
• /
• pp.648-658
• /
• 2022

Objective: The identification of nonlinear mixed models that describe the growth trajectory of New Zealand rabbits was performed based on weight records and carcass measures obtained using ultrasonography. Methods: Phenotypic records of body weight (BW) and loin eye area (LEA) were collected from 66 animals raised in a didactic-productive module of cuniculture located in the southern Piaui state, Brazil. The following nonlinear models were tested considering fixed parameters: Brody, Gompertz, Logistic, Richards, Meloun 1, modified Michaelis-Menten, Santana, and von Bertalanffy. The coefficient of determination (R²), mean squared error, percentage of convergence of each model (%C), mean absolute deviation of residuals, Akaike information criterion (AIC), and Bayesian information criterion (BIC) were used to determine the best model. The model that best described the growth trajectory for each trait was also used under the context of mixed models, considering two parameters that admit biological interpretation (A and k) with random effects. Results: The von Bertalanffy model was the best fitting model for BW according to the highest value of R² (0.98) and lowest values of AIC (6,675.30) and BIC (6,691.90). For LEA, the Logistic model was the most appropriate due to the results of R² (0.52), AIC (783.90), and BIC (798.40) obtained using this model. The absolute growth rates estimated using the von Bertalanffy and Logistic models for BW and LEA were 21.51g/d and 3.16 cm², respectively. The relative growth rates at the inflection point were 0.028 for BW (von Bertalanffy) and 0.014 for LEA (Logistic). Conclusion: The von Bertalanffy and Logistic models with random effect at the asymptotic weight are recommended for analysis of ponderal and carcass growth trajectories in New Zealand rabbits. The inclusion of random effects in the asymptotic weight and maturity rate improves the quality of fit in comparison to fixed models.

• 한국병원경영학회지
• /
• 제21권2호
• /
• pp.24-36
• /
• 2016

The aims of this study is to investigate the status of nursing care delivery systems and nurse staffing levels and to analyze differences in the quality of nursing care by the type of nursing care delivery system. This research was based on data from 723 nurses working in 55 medical and surgical units in 26 general hospitals. Descriptive statistics on nurse staffing levels and the nursing care delivery system, and multi-level logistic regression were used to estimate the determinants of quality of nursing care. The number of patients per nurse is 17.74 patients in functional nursing care and 15.56 patients in total nursing care. In comparison to hospitals adopting total nursing care, hospitals with functional nursing care had greater patients. The nurses rated units using total nursing care as significantly better quality of nursing care than the units with functional nursing care. Total nursing care or modified total nursing care, rather than functional nursing care, could lead to improvement in the quality of care(total nursing care OR=3.895, modified total nursing care OR=2.475). Patient-centered approaches under proper circumstances can be successfully implemented and the positive effects demonstrated.