• 제목/요약/키워드: logistic function

검색결과 445건 처리시간 0.023초

Examining the Quality of Life Related to Fall Experience in Chronic Stroke Patients

  • Lee, Ju-Hwan;Park, Shin-Jun
    • 대한물리의학회지
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    • 제11권3호
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    • pp.73-80
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    • 2016
  • PURPOSE: The purpose of this study was to investigate the quality of life related to fall experiences in chronic stroke patients. METHODS: This cross-sectional study included 117 patients with stroke from 3 hospitals in D metropolitan city. General characteristics, including fall experiences and quality of life, were assessed through a face-to-face interviews conducted in a quiet place using a questionnaire. Measurement of quality of life in stroke patients was conducted using the Korean Stroke Specific Quality of Life Scale (SS-QOL). To identify the SS-QOL items related to fall experiences, the items of the SS-QOL were considered as independent variables, and the variables that were significantly different according to fall experiences were identified using a univariate analysis. A binary logistic regression was then performed using fall experiences as the independent variable. RESULTS: According to the univariate analysis, self help activities, social role, and upper extremity function were significantly lower in the fall group than that in the non-fall group (p<.05). The findings of the binary logistic regression confirmed that social roles and upper extremity function were the SS-QOL items that were related to fall experience in chronic stroke patients. CONCLUSION: These findings suggest that social roles and upper extremity function may be risk factors for fall experience in patients with chronic stroke.

Estimating Suitable Probability Distribution Function for Multimodal Traffic Distribution Function

  • Yoo, Sang-Lok;Jeong, Jae-Yong;Yim, Jeong-Bin
    • 해양환경안전학회지
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    • 제21권3호
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    • pp.253-258
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    • 2015
  • The purpose of this study is to find suitable probability distribution function of complex distribution data like multimodal. Normal distribution is broadly used to assume probability distribution function. However, complex distribution data like multimodal are very hard to be estimated by using normal distribution function only, and there might be errors when other distribution functions including normal distribution function are used. In this study, we experimented to find fit probability distribution function in multimodal area, by using AIS(Automatic Identification System) observation data gathered in Mokpo port for a year of 2013. By using chi-squared statistic, gaussian mixture model(GMM) is the fittest model rather than other distribution functions, such as extreme value, generalized extreme value, logistic, and normal distribution. GMM was found to the fit model regard to multimodal data of maritime traffic flow distribution. Probability density function for collision probability and traffic flow distribution will be calculated much precisely in the future.

랜탈 물류산업의 효율적 운영방안 (Efficient Management of Rental Logistics Industry)

  • 김준효;양광모;강경식
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2002년도 추계학술대회
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    • pp.227-232
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    • 2002
  • Enormous flocks by the reduced life cycle of products caused by the technological innovation if later 20 century, development of new materials and diversified demands of customers appeared as the pressing element causing the trouble in management of companies, and when considering the logistic costs that are imposed to companies in terms of function, the costs related to the stock topped the list of costs, followed by the transportation ones, and for pallet pool system, inventory of stocks is very difficult by the number of companies. Reducing the logistic cost may be accomplished by numbers of logistic management methods, but the most fundamental and essential one is the accomplishment of the consistent pallet system that is the core of unit load system, and the purpose of consistent pallet system is the treatment of logistic functions such as transportation, storage and unloading with consistent pallet system, and increasing the turnover ratio is required for the improvement of the system. As the turnover ratios is increased, more pallets will be used so, numbers of empty pallets will be increased accordingly by returning the pallet. Therefore, in this study, we will establish the effective stock management system by comparing with the other existing stock management system after looking at the concept and examples of pallet full system in order to resolved this kind of problem.

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파렛트 풀 시스템의 효율적인 운영에 관한 연구 (A Study on Efficient Management of Pal1et Pool System)

  • 김준효;양광모;강경식
    • 대한안전경영과학회지
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    • 제5권1호
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    • pp.33-43
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    • 2003
  • Enormous stocks by the reduced life cycle of products caused by the technological innovation in later 20 century, development of new materials and diversified demands of customers appeared as the pressing element causing the trouble in management of companies, and when considering the logistic costs that are imposed to companies in terms of function, the costs related to the stock topped the list of costs, followed by the transportation ones, and for pallet pool system, inventory of stocks is very difficult by the number of companies. Reducing the logistic cost may be accomplished by numbers of logistic management methods, but the most fundamental and essential one is the accomplishment of the consistent pallet system that is the core of unit load system, and the purpose of consistent pallet system is the treatment of logistic functions such as transportation, storage and unloading with consistent pallet system, and increasing the turnover ratio is required for the improvement of the system. As the turnover ratios is increased, more pallets will be used so, numbers of empty pallets will be increased accordingly by returning the pallet. Therefore, in this study, we will establish the effective stock management system by comparing with the other existing stock management system after looking at the concept and examples of pallet full system in order to resolved this kind of problem.

소프트웨어 개발단계의 신뢰도에 관한 연구 (A Study on the Reliability of S/W during the Developing Stage)

  • 양계탁
    • 한국산업정보학회논문지
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    • 제14권5호
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    • pp.61-73
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    • 2009
  • 1972년에 소프트웨어의 신뢰도 문제가 제기되면서부터 개발 중인 소프트웨어의 신뢰도를 평가하고 목표치까지 신뢰도를 성장시키는 방법이 연구되었으며, 테스트 기간 동안에 소요되는 비용 문제까지를 포함하여 적정 인도시기를 결정하는 여러 방법이 제안되었다. 이러한 모델들 중 많은 연구에서 소프트웨어 테스트 전 단계를 거쳐서 테스트 노력이 상수인 것으로 가정하거나 또는 아예 고려하지도 않았으나, 그 후 몇몇 논문을 통하여 테스트 노력을 고려한 소프트웨어의 신뢰도 평가가 중요한 인자인 것으로 발포되었다. 여러 산업 현장의 경험 데이터에 의하면 그 형태가 지수함수형, 레일레이형, 웨이불형, 로지스틱형 테스트 노력 함수 중 하나인 것으로 보고되었다. 따라서 본 논문에서는 이 네 가지 형태의 테스트 노력을 가진 소프트웨어의 신뢰도 성장에 필요한 각종 파라미터를 구하는 방법에 대하여 제안한다. 개발 현장에서 관찰된 테스트 노력 데이터와 결함검출을 비교하여 어느 형태의 테스트 노력 곡선이 그 경우에 적합한가를 연구하는 한편, 목표 신뢰도에 맞는 발행 시기를 결정하는 문제를 연구한다.

Occupational factors affecting the decline in pulmonary function among male farmers using occupational pesticide in Gyeonggi-do, South Korea

  • Sooyeon Lee;Jiyoung Han;Seung Hee Woo;Soo-Jin Lee
    • Annals of Occupational and Environmental Medicine
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    • 제34권
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    • pp.42.1-42.11
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    • 2022
  • Background: Occupational pesticide exposure is a potential risk for respiratory health effects. Most clinical studies on pesticide exposure were related to acute exposure, and only a few studies on chronic exposure have been conducted. This study investigated the chronic respiratory health status and the chronic effects of occupational pesticide exposures of farmers in Gyeonggi-do. Methods: Surveys and pulmonary function tests were conducted on 1,697 farmers in 16 regions of Gyeonggi-do. The structured questionnaire included demographic characteristics, medical history, recent respiratory symptoms and diseases, and work-related conditions, and was conducted through one-on-one interviews. The prevalence of respiratory diseases was compared by the odds ratios (ORs) at 95% confidence intervals (CIs) estimated by logistic regression analysis. Additional multivariate logistic regression analysis was also conducted. Results: Pesticide work groups showed significant association with an obstructive pattern in the lung function test (unadjusted OR, 2.38; 95% CI, 1.17-5.52). Selected work-related variables of pesticide exposure were 'start age,' 'cumulative duration,' 'mixing pesticides,' and 'protection(goggle).' The obstructive pattern of lung function test showed significant associations with mixing pesticides (OR, 2.30; 95% CI,1.07-5.46), and protection (goggle) use (OR, 0.34; 95% CI, 0.12-0.79). Conclusions: Mixing two or more pesticides showed a significant association. Wearing goggles can be seen as an indicator of awareness of the protective equipment and proper wearing of protective equipment, and loss of pulmonary function can be prevented when appropriate protection is worn.

효율적인 국방물자 보급체인을 위한 웹 기반 정보체계의 설계 및 구현 ((The Design and Development of a Web Based Information System for Effective Military Material Supply Chains))

  • 우훈식;이봉호;박정갑
    • 한국국방경영분석학회지
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    • 제35권1호
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    • pp.83-93
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    • 2009
  • 미래전은 정밀 타격과 같은 첨단 군 기술에 의한 효과 중심의 마비전이다. 이러한 미래전에서 작전 주도권과 집중력 강화를 지원하기 위한 새로운 개념의 군수 역할이 요구되고 있으며 전투원 및 전투부대 중심의 집중군수가 대안으로 제시되고 있다. 이와 같은 집중 군수를 실현하기 위해서는 전 제대의 자산을 실시간으로 파악 할 수 있는 자산가시화가 선행되어야 하지만 현재 우리 군에서 사용하고 있는 군수정보체계는 제한적인 정보만을 제공하고 있다. 본 연구에서는 웹 기반 2종 및 4종 군수품 관리 시스템의 구현 방안을 제시하였다. 제시된 대안 체계 시제는 전투원 및 전투부대 중심으로 군수가 지원될 수 있도록 전투부대 중심의 업무 프로세스 통합과 군수 기능간 동기화를 추구하였다. 또한 집중 군수의 필수 요소인 자산 가시화를 제공함으로써 이를 통한 신속하고 효율적인 군수 지원이 가능함을 확인하였다.

Mapping the Spatial Distribution of IRG Growth Based on UAV

  • Na, Sang-Il;Park, Chan-Won;Kim, Young-Jin;Lee, Kyung-Do
    • 한국토양비료학회지
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    • 제49권5호
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    • pp.495-502
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    • 2016
  • Italian Ryegrass (IRG), which is known as high yielding and the highest quality winter annual forage crop, is grown in mid-south area in Korea. The objective of this study was to evaluate the use of unmanned aerial vehicle (UAV) for the monitoring IRG growth. Unmanned aerial vehicle imagery obtained from middle March to late May in Nonsan, Chungcheongnam-do. Unmanned aerial vehicle imagery corrected geometrically and atmospherically to calculate normalized difference vegetation index (NDVI). We analyzed the relationships between $NDVI_{UAV}$ of IRG and biophysical measurements such as plant height, fresh weight, and dry weight over an entire IRG growth period. The similar trend between $NDVI_{UAV}$ and growth parameters was shown. Correlation analysis between $NDVI_{UAV}$ and IRG growth parameters revealed that $NDVI_{UAV}$ was highly correlated with fresh weight (r=0.988), plant height (r=0.925), and dry weight (r=0.853). According to the relationship among growth parameters and $NDVI_{UAV}$, the temporal variation of $NDVI_{UAV}$ was significant to interpret IRG growth. Four different regression models, such as (1) Linear regression function, (2) Linear regression through the origin, (3) Power function, and (4) Logistic function were developed to evaluate the relationship between temporal $NDVI_{UAV}$ and measured IRG growth parameters. The power function provided higher accurate results to predict growth parameters than linear or logistic functions using coefficient of determination. The spatial distribution map of IRG growth was in strong agreement with the field measurements in terms of geographical variation and relative numerical values when $NDVI_{UAV}$ was applied to power function. From these results, $NDVI_{UAV}$ can be used as a new tool for monitoring IRG growth.

Some Exponentiated Distributions

  • Ali, M. Masoom;Pal, Manisha;Woo, Jung-Soo
    • Communications for Statistical Applications and Methods
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    • 제14권1호
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    • pp.93-109
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    • 2007
  • In this paper we study a number of new exponentiated distributions. The survival function, failure rate and moments of the distributions have been derived using certain special functions. The behavior of the failure rate has also been studied.

On Chaotic Behavior of Fuzzy Inferdence Rule Based Nonlinear Functions

  • Ikoma, Norikazu
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.861-864
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    • 1993
  • This research provides the results of a trial to generate the chaos by using nonlinear function constructed by fuzzy inference rules. The chaos generation function or chaotic behavior can be obtained by using Takagi-Sugeno fuzzy model with some constraint of the relationship of its parameters. Two examples are shown in this research. The first is simple example that construct of logistic image by fuzzy model. The second is more complicated one that provide the chaotic time series by non-linear autoregression based on fuzzy model. Simulated results are shown in these examples.

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