• Title, Summary, Keyword: Test of heterogeneity

Search Result 155, Processing Time 0.043 seconds

Assessment of Cognition in Schizophrenia Using Trail Making Test: A Meta-Analysis

  • Laere, Erna;Tee, Shiau Foon;Tang, Pek Yee
    • Psychiatry investigation
    • /
    • v.15 no.10
    • /
    • pp.945-955
    • /
    • 2018
  • Objective The present meta-analysis aimed to analyze the cognitive performance of schizophrenia patients measured by Trail Making Tests (TMT) and the contribution of socio-demographic factors to cognitive impairments. Methods PubMed and PsycARTICLES databases were searched for the studies published between January 1985 and November 2017. Data were drawn from 19 studies encompassing 1095 patients and 324 controls. The effect size and heterogeneity were assessed with Comprehensive Meta-Analysis version 2 using random-effect model. Results Overall, the results showed that the schizophrenia patients performed significantly (p<0.001) worse than healthy controls in both TMT-A and B. However, concurrent substance abuse, clinical status (inpatient or outpatient), duration of education and duration of illness were not associated with cognitive impairment among the schizophrenia patients. Conclusion The present meta-analysis confirmed the cognitive processing speed and flexibility of schizophrenia patients were impaired. However, their duration of education, duration of illness and clinical status (inpatient or outpatient) were not the risk factors.

Variation in Demography of Taraxacum officinale Seeds Harvested from Different Seasons

  • Yang, Hyo-Sik;Oh, Man-Ho
    • The Korean Journal of Ecology
    • /
    • v.26 no.2
    • /
    • pp.82-86
    • /
    • 2003
  • We investigated the variation in adaptation to growth for four ecotypically-differentiated population of Taraxacum officinale found naturally in temporal environmental heterogeneity. Seeds collected from the four seasons were germinated in incubators and were grown for four months in greenhouse to test genetic variation among biotypes. Biotypes, segregated by seeds collected seasonally, were the part of natural population in Mokpo, South Korea. Each biotype was different in total dry weight of seeds, biomass, and leaf area, confirming previous finding. Differences between biotypes grown under a common environment indicated a genetic basis to their distinct demographic rates. Therefore, biotypes with similar annual rates of growth and contrasting seasonal rates should persist in the population. This differential response suggests that temporal variation in environment may be responsible, in part, for the maintenance of genetic variation within populations.

Analysis of the shear failure process of masonry by means of a meso-scopic mechanical modeling approach

  • Wang, Shuhong;Tang, Chun'an;Jia, Peng
    • Structural Engineering and Mechanics
    • /
    • v.24 no.2
    • /
    • pp.181-194
    • /
    • 2006
  • The masonry is a complex heterogeneous material and its shear deformation and fracture is associated with very complicated progressive failures in masonry structure, and is investigated in this paper using a mesoscopic mechanical modelling, Considering the heterogeneity of masonry material, based on the damage mechanics and elastic-brittle theory, the newly developed Material Failure Process Analysis (MFPA) system was brought out to simulate the cracking process of masonry, which was considered as a three-phase composite of the block phase, the mortar phase and the block-mortar interfaces. The crack propagation processes simulated with this model shows good agreement with those of experimental observations by other researchers. This finding indicates that the shear fracture of masonry observed at the macroscopic level is predominantly caused by tensile damage at the mesoscopic level. Some brittle materials are so weak in tension relative to shear that tensile rather than shear fractures are generated in pure shear loading.

A Predictive Two-Group Multinormal Classification Rule Accounting for Model Uncertainty

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
    • /
    • v.26 no.4
    • /
    • pp.477-491
    • /
    • 1997
  • A new predictive classification rule for assigning future cases into one of two multivariate normal population (with unknown normal mixture model) is considered. The development involves calculation of posterior probability of each possible normal-mixture model via a default Bayesian test criterion, called intrinsic Bayes factor, and suggests predictive distribution for future cases to be classified that accounts for model uncertainty by weighting the effect of each model by its posterior probabiliy. In this paper, our interest is focused on constructing the classification rule that takes care of uncertainty about the types of covariance matrices (homogeneity/heterogeneity) involved in the model. For the constructed rule, a Monte Carlo simulation study demonstrates routine application and notes benefits over traditional predictive calssification rule by Geisser (1982).

  • PDF

Impact of Different Green-Ampt Model Parameters on the Distributed Rainfall-Runoff Model FLO-2D owing to Scale Heterogeneity (분포형 강우-유출 모형에서 토양도 격자크기 효과가 Green-Ampt 모형의 매개변수와 모의된 강우손실에 미치는 영향)

  • Hwang, Ji-hyeong;Lee, Khil-Ha
    • Journal of Environmental Science International
    • /
    • v.29 no.1
    • /
    • pp.15-23
    • /
    • 2020
  • The determination of soil characteristics is important in the simulation of rainfall runoff using a distributed FLO-2D model in catchment analysis. Digital maps acquired using remote sensing techniques have been widely used in modern hydrology. However, the determination of a representative parameter with spatial scaling mismatch is difficult. In this investigation, the FLO-2D rainfall-runoff model is utilized in the Yongdam catchment to test sensitivity based on three different methods (mosaic, arithmetic, and predominant) that describe soil surface characteristics in real systems. The results show that the mosaic method is costly, but provides a reasonably realistic description and exhibits superior performance compared to other methods in terms of both the amount and time to peak flow.

Ontology-based Knowledge Framework for Product Development (제품개발을 위한 온톨로지 기반 지식 프레임워크)

  • Suh H.W.;Lee J.H.
    • Korean Journal of Computational Design and Engineering
    • /
    • v.11 no.2
    • /
    • pp.88-96
    • /
    • 2006
  • This paper introduces an approach to ontology-based framework for knowledge management in a product development domain. The participants in a product life cycle want to share the product knowledge without any heterogeneity. However, previous knowledge management systems do not have any conceptual specifications of their knowledge. We suggest the three levels of knowledge framework. First level is an axiom, which specifies the semantics of concepts and relations. Second level is a product development knowledge map. It defines the common domain knowledge which domain experts agree with. Third level is a specialized knowledge for domain, which includes three knowledge types; expert knowledge, engineering function and data-analysis-based knowledge. We propose an ontology-based knowledge framework based on the three levels of knowledge. The framework has a uniform representation; first order logic to increase integrity of the framework. We implement the framework using prolog and test example queries to show the effectiveness of the framework.

Local Feature Learning using Deep Canonical Correlation Analysis for Heterogeneous Face Recognition (이질적 얼굴인식을 위한 심층 정준상관분석을 이용한 지역적 얼굴 특징 학습 방법)

  • Choi, Yeoreum;Kim, Hyung-Il;Ro, Yong Man
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.5
    • /
    • pp.848-855
    • /
    • 2016
  • Face recognition has received a great deal of attention for the wide range of applications in real-world scenario. In this scenario, mismatches (so called heterogeneity) in terms of resolution and illumination between gallery and test face images are inevitable due to the different capturing conditions. In order to deal with the mismatch problem, we propose a local feature learning method using deep canonical correlation analysis (DCCA) for heterogeneous face recognition. By the DCCA, we can effectively reduce the mismatch between the gallery and the test face images. Furthermore, the proposed local feature learned by the DCCA is able to enhance the discriminative power by using facial local structure information. Through the experiments on two different scenarios (i.e., matching near-infrared to visible face images and matching low-resolution to high-resolution face images), we could validate the effectiveness of the proposed method in terms of recognition accuracy using publicly available databases.

The Analysis of Oceans and Fisheries Human Resources Development Education Efficiency Using Bootstrap-DEA (Bootstrap-DEA를 이용한 해양수산 인재 양성교육의 효율성 분석에 관한 연구)

  • Kim, Jong-Cheon;KIM, Byoung-Ho
    • The Journal of Fisheries Business Administration
    • /
    • v.47 no.1
    • /
    • pp.63-86
    • /
    • 2016
  • The purpose of this study is to investigate production efficiency of Oceans and Fisheries Human Resources Development Programs Efficiency using Bootstrap-DEA. The study extracts 33 officials curriculum, 11 fisheries managers curriculum for its analytical. First, the study estimates technical, pure technical, and scale efficiency of each curriculums based on traditional DEA under the assumption of CRS and VRS. 8(official 7, managers 1) curriculums are identified as efficient DMUs under the CCR-model, and 13(official 10, managers 3) under the BCC-model. We provide inputs that allow inefficient curriculum to be efficient DMUs on a production frontier, and a reference set for their bench-marking. Second, rank test, Wilcoxon-Mann-Whitney test to find a statistical significance of heterogeneity existing in efficiences between Bootstrap-DEA tenical vs Bootstrap-DEA pure technical was no significant difference. We have identified that G10, 11, 12 13, 25, 31, 33, 39 curriculums are the most efficiently produced in the technical and pure technical efficiency. Also we managed to measure the inefficiency which exists in efficiently produced curriculums when estimating the bias corrected efficiency scores. In Technical efficiency, Operation and facility was significant at the 10%. In Pure technical efficiency, facility was significant at the 10%.

A Study on the Chemical Integration between Coating Sheets of Complex Waterproofing Method Using Modified Amine-Treated Nonwoven Fabric (변성아민 처리된 부직포를 이용한 복합방수공법의 도막·시트 간 화학적 일체화에 관한 연구)

  • Kim, Sun-Do;Kim, Jin-Sung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • /
    • pp.118-119
    • /
    • 2017
  • The combined waterproofing method is an excellent method to overcome the disadvantages of the single waterproofing method by composing two or more materials to complement each other, but it is a method that can cause defects such as separation and peeling between materials due to the heterogeneity of the applied two materials. In order to improve this, in this study, we aimed to develop a technology for inducing chemical unification between materials through a urea reaction with a coating material applied on the lower side by laminating a nonwoven fabric treated with a modified amine on the back surface of the sheet material, The adhesion performance test was carried out with the presence or absence of denatured amine treated nonwovens as variables. As a result of the test, it was confirmed that the adhesion performance of the specimen to which the modified amin - treated nonwoven fabric was applied was improved by about 60% or more as compared with the specimens not having the denatured amine treated specimen.

  • PDF

Application of Impact Echo Method to Civil Engineering Fields (토목공학 분야에서의 충격반향법의 응용)

  • Jung, Yun-Moon;Ha, Hee-Sang
    • Geophysics and Geophysical Exploration
    • /
    • v.3 no.3
    • /
    • pp.94-100
    • /
    • 2000
  • Many nondestructive test methods used for metallic materials have some limit in application to concrete materials due to their heterogeneity. Impact echo method utilizes the resonance frequency of reflected seismic waves from defects or the boundary between two materials and can be applied to investigate the interior of concrete structures. In this study, a field data acquisition system for the impact echo method was assembled and field tests under various conditions were performed. The impact echo method was applied for investigating thickness/defects/backfilling of concrete structures/tunnel lining/airport pavement. The applicability of the impact echo method to the civil engineering field was substantiated by providing results within $10\%$ errors.

  • PDF