• Title/Summary/Keyword: Chi-Square

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Performance of APACHE IV in Medical Intensive Care Unit Patients: Comparisons with APACHE II, SAPS 3, and MPM0 III

  • Ko, Mihye;Shim, Miyoung;Lee, Sang-Min;Kim, Yujin;Yoon, Soyoung
    • Acute and Critical Care
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    • v.33 no.4
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    • pp.216-221
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    • 2018
  • Background: In this study, we analyze the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) II, APACHE IV, Simplified Acute Physiology Score (SAPS) 3, and Mortality Probability Model $(MPM)_0$ III in order to determine which system best implements data related to the severity of medical intensive care unit (ICU) patients. Methods: The present study was a retrospective investigation analyzing the discrimination and calibration of APACHE II, APACHE IV, SAPS 3, and $MPM_0$ III when used to evaluate medical ICU patients. Data were collected for 788 patients admitted to the ICU from January 1, 2015 to December 31, 2015. All patients were aged 18 years or older with ICU stays of at least 24 hours. The discrimination abilities of the three systems were evaluated using c-statistics, while calibration was evaluated by the Hosmer-Lemeshow test. A severity correction model was created using logistics regression analysis. Results: For the APACHE IV, SAPS 3, $MPM_0$ III, and APACHE II systems, the area under the receiver operating characteristic curves was 0.745 for APACHE IV, resulting in the highest discrimination among all four scoring systems. The value was 0.729 for APACHE II, 0.700 for SAP 3, and 0.670 for $MPM_0$ III. All severity scoring systems showed good calibrations: APACHE II (chi-square, 12.540; P=0.129), APACHE IV (chi-square, 6.959; P=0.541), SAPS 3 (chi-square, 9.290; P=0.318), and $MPM_0$ III (chi-square, 11.128; P=0.133). Conclusions: APACHE IV provided the best discrimination and calibration abilities and was useful for quality assessment and predicting mortality in medical ICU patients.

Robust Scheme of Segmenting Characters of License Plate on Irregular Illumination Condition (불규칙 조명 환경에 강인한 번호판 문자 분리 기법)

  • Kim, Byoung-Hyun;Han, Young-Joon;Hahn, Hern-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.11
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    • pp.61-71
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    • 2009
  • Vehicle license plate is the only way to check the registrated information of a vehicle. Many works have been devoted to the vision system of recognizing the license plate, which has been widely used to control an illegal parking. However, it is difficult to correctly segment characters on the license plate since an illumination is affected by a weather change and a neighboring obstacles. This paper proposes a robust method of segmenting the character of the license plate on irregular illumination condition. The proposed method enhance the contrast of license plate images using the Chi-Square probability density function. For segmenting characters on the license plate, binary images with the high quality are gained by applying the adaptive threshold. Preprocessing and labeling algorithm are used to eliminate noises existing during the whole segmentation process. Finally, profiling method is applied to segment characters on license plate from binary images.

A Study on Personality and Ordinary Symptoms according to Soyangin's Major Constitutional Medicine (소양인(少陽人) 주요(主要) 처방(處方) 간의 성격(性格) 및 소증(素證) 차이(差異)에 관한 연구(硏究))

  • Kim, Seong-Tae;Choi, Ae-Ryun
    • Journal of Sasang Constitutional Medicine
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    • v.26 no.1
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    • pp.82-97
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    • 2014
  • Objectives The purpose of this study was to survey the Personality and Ordinary Symptoms of Soyangin and to compare the tendency of their personality and symptoms according to Soyangin's major prescription. Methods 331 Soyangin's personality and ordinary symptoms data registered to SCIB(Sasang Constitutional Information Bank) were used. All data were analyzed with Chi square test. Some data were ranked and analyzed with Kruskal-Wallis test and Mann-Whitney test(with Bonferroni correction). Chi square and Kruskal-Wallis test's significant P value was 0.05. Mann-Whitney test's significant P value was 0.005. Results & Conclusions In Chi square test, there is difference in personality and symptoms in Soyangin's major prescription as followed, the degree of masculinity and femininity, the degree of patience, the condition of stool, the degree of appetite, good or bad in digesting, amount of meal, the speed of eating, amount of drinking water, the temperature of drinking water, coldness and hotness in abdomen or not. In Kruskal-Wallis test and Mann-Whitney test, Yanggyuksanhwa-tang is more masculine than Dokhwaljihwang-tang, Hyeongbangsabaek-san, Hyeongbangjihwangtang. Dokhwaljihwang-tang is less appetite than Yanggyuksanhwa-tang and Hyeongbangsabaek-san. Yanggyuksanhwa- tang is more fast in eating than Hyeongbangjihwang-tang.

The Analysis of Association between Learning Styles and a Model of IoT-based Education : Chi-Square Test for Association

  • Sayassatov, Dulan;Cho, Namjae
    • Journal of Information Technology Applications and Management
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    • v.27 no.3
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    • pp.19-36
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    • 2020
  • The Internet of things (IoT) is a system of interrelated computed devices, digital machines and any physical objects which are provided with unique identifiers and the potential to transmit data to people or machine (M2M) without requiring human interaction. IoT devices can be used to monitor and control the electrical and electronic systems used in different fields like smart home, smart city, smart healthcare and etc. In this study we introduce four imaginary IoT devices as a learning support assistants according to students' dominant learning styles measured by Honey and Mumford Learning Styles: Activists, Reflectors, Theorists and Pragmatists. This research emphasizes the association between students' strong learning styles and a preference to appropriate IoT devices with specific characteristics. Moreover, different levels of IoT devices' architecture are clearly explained in this study where all the artificial devices are designed based on this structure. Data analysis of experiment were measured by the use of chi square test for association and research results showed the statistical significance of the estimated model and the impacts of each category over the model where we finally got accurate estimates for our research variables. This study revealed the importance of considering the students' dominant learning styles before inventing a new IoT device.

On Some Distributions Generated by Riff-Shuffle Sampling

  • Son M.S.;Hamdy H.I.
    • International Journal of Contents
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    • v.2 no.2
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    • pp.17-24
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    • 2006
  • The work presented in this paper is divided into two parts. The first part presents finite urn problems which generate truncated negative binomial random variables. Some combinatorial identities that arose from the negative binomial sampling and truncated negative binomial sampling are established. These identities are constructed and serve important roles when we deal with these distributions and their characteristics. Other important results including cumulants and moments of the distributions are given in somewhat simple forms. Second, the distributions of the maximum of two chi-square variables and the distributions of the maximum correlated F-variables are then derived within the negative binomial sampling scheme. Although multinomial theory applied to order statistics and standard transformation techniques can be used to derive these distributions, the negative binomial sampling approach provides more information and deeper insight regarding the nature of the relationship between the sampling vehicle and the probability distributions of these functions of chi-square variables. We also provide an algorithm to compute the percentage points of these distributions. We supplement our findings with exact simple computational methods where no interpolations are involved.

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Analysis of the Statistical Techniques and Errors in the Field of Sasang Constitution Researches: from 2011 to 2015 (최근 5년간(2011~2015) 사상체질분야 논문의 통계기법 분석 및 오류에 관한 연구)

  • Kim, Sujung;Kim, Sanghyuk;Lee, Siwoo
    • Journal of Sasang Constitutional Medicine
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    • v.28 no.1
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    • pp.51-56
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    • 2016
  • Objectives This study was to identify the types of errors in the statistical analysis and trends of previous reported papers that used various statistical techniques.Methods We have selected 118 original articles for statistical review from the OASIS(http://oasis.kiom.re.kr) and the Pubmed(http://www.pubmed.gov) in the field of Sasang constitutional medicine. Published year was restricted from 2011 to 2015.Results 1. The ANOVA(25.72%) was the statistic of choice overall, followed by the chi-square test(21.74%), regression analysis(14.13%), t-test(11.59%), and etc. 2. By examining the errors of the statistical methods, there were 42(59.2%) thesis with errors among 71 thesis using ANOVA, 19(31.7%) thesis among 60 thesis using chi-square test, and 35(89.7%) over 39 thesis using regression analysis.Conclusions To improve the quality of Sasang Constitution, the participation of statisticians in research design will reduce the significant errors in statistical interpretation of the results.

Wetland transformation through Water Resource Users Association; The case of Rwamuthambi Sub Catchment area, Kenya

  • Kumunga, Eunice Muthoni;Ndiwa, Titus Chemandwa;Muthama, Nzioka John
    • Journal of Wetlands Research
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    • v.22 no.3
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    • pp.200-216
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    • 2020
  • Many studies conducted in Kenya regarding water resource governance have focused on the mandate of Water Resource Users Associations (WRUAs) with less attention being accorded to their effectiveness in conservation of wetlands. This study assessed the effectiveness of WRUA committees, and challenges faced in conservation of Rwamuthambi Sub-catchment. The study employed exploratory descriptive research design. Data was collected through questionnaires, semi-structured interviews, observations and review of secondary data. Chi square and descriptive statistics was used to analyze the data. The survey results revealed that only 15% of WRUA committee understood water resources management while 35% were aware of relevant legislations. Factors of wetland degradation showed significant association with existence of WRUA (χ2 (4, N=180) = 20.46, p< .01) where (χ2- chi square (degrees of freedom, N = sample size) = chi-square statistic value, p = p value), although WRUA contributions were perceived differently per agro-ecological zone (χ2 (8, N=147) = 15.51, p>.05). Challenges unearthed were inadequate financial and human resources, lack of understanding, ineffective collaborative governance, poor support from county government and private ownership of riparian land reserve. There is need for WRUAs to embrace collaborative governance for effective conservation of wetlands. Integration of sub catchment management plan with county land use plans and policy review is also required.

On spectral and statistical characteristics of sea waves by the typhoons (태풍에 의한 파랑의 스펙트럼 및 통계적 특성)

  • Shim, Jae-Seol;Oh, Byung-Chul;Kim, Sang-Ik
    • Water for future
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    • v.22 no.4
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    • pp.441-451
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    • 1989
  • Using the wave data by typhoons LEE, VERA, THELMA which gave great damages in the Korean penisula, the significant waves based on zero-up & down crossing and Tucker-Draper method are compared with those from the wave energy spectrum. And the histograms of individual waves obtained from zero-up crossing method are presented and compared with the Rayleigh, Weibull, Gluhovski, Ibrageemov and Goda distributions, and also the Chi-square goodness of fit test is applied to each theoretical distributions. It is shown that the significant wave heights by zero-up crossing method are very well agreed to those by energy spectrum method. The wave heights are found to well follow the Rayleigh and Goda distributions by the Chi-square test.

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A Study on the Construction and Use of CD-ROM Network Systems at University Libraries (대학도서관의 CD-ROM 네트워크 시스템 구축 현황 및 이용에 관한 연구)

  • Kim Soon-Won;Chung Young-Mee
    • Journal of the Korean Society for Library and Information Science
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    • v.33 no.3
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    • pp.145-167
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    • 1999
  • This study aims to identify factors to be considered in designing and operating CD-ROM network systems efficiently and provide designers and operators with basic guidelines. In this study, the current status and problems of CD-ROM network systems at 72 domestic university libraries are examined, and user behavior and satisfaction of 64 actual users in 3 universities are analyzed. In addition, to examine the influenced correlation among the factors such as user satisfaction, system operating policy, system resources and system performance, $\chi^2(Chi-Square)$ test, F test and regression analysis are carried out and the factors influencing user satisfaction are examined.

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A Study on the State Estimation for Distribution Substations (변전소 상태변수 추정에 관한 연구)

  • 이흥재;박성민;이경섭
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.3
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    • pp.103-109
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    • 2003
  • The validity of measured data is fundamental factor for the power system automation Measured values could have errors that are caused by the communication errors and malfunctioning measuring devices. The accuracy and reliability of measured values at a substation is an important condition for robust and fault tolerant automata. Errors can be reduced by state estimation, however, global reliability of state estimation goes down in case of the existence of some bad data In this paper, a least square state estimation and bad sensor detection algorithm based on chi-square theory, ale proposed and it is applied to a domestic 154kV distribution substations. A simulator together with user friendly graphic users interface is developed using C language and Visual Basic. TCP/IP is equipped for future connection with other operation systems.