• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.359-366
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• 2005

Most engineering optimization are based on numerical linear and nonlinear programming methods that require substantial gradient information and usually seek to improve the solution in the neighborhood of a starting point. These algorithm, however, reveal a limited approach to complicated real-world optimization problems. If there is more than one local optimum in the problem, the result may depend on the selection of an initial point, and the obtained optimal solution may not necessarily be the global optimum. This paper describes a new harmony search(HS) meta-heuristic algorithm-based approach for structural size optimization problems with continuous design variables. This recently developed HS algorithm is conceptualized using the musical process of searching for a perfect state of harmony. It uses a stochastic random search instead of a gradient search so that derivative information is unnecessary. Two classical space truss optimization problems are presented to demonstrate the effectiveness and robustness of the HS algorithm. The results indicate that the proposed approach is a powerful search and optimization technique that may yield better solutions to structural engineering problems than those obtained using current algorithms.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.612-620
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• 2017

Relay coordination in power system is a complex problem and so far, meta-heuristic algorithms and other methods as an alternative approach may not properly deal with large scale relay coordination due to their huge time consuming computation. In some cases the relay coordination could be unachievable. As the urgency for a proper approach is essential, in this paper an innovative and simple relay coordination method is introduced that is able to be applied on optimization algorithms for relay protection coordination. The objective function equation of operating time of relays are divided into two separate functions with less constraints. As the analytical results show here, this equivalent method has a remarkable speed with high accuracy to coordinate directional relays. Two distribution systems including directional overcurrent relays are studied in DigSILENT software and the collected data are examined in MATLAB. The relay settings of this method are compared with particle swarm optimization and genetic algorithm. The analytical results show the correctness of this mathematical and practical approach. This fast coordination method has a proper velocity of convergence with low iteration that can be used in large scale systems in practice and also to provide a feasible solution for protection coordination in smart grids as online or offline protection coordination.

• Structural Engineering and Mechanics
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• v.61 no.2
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• pp.283-293
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• 2017

The main contribution of the present paper is to propose an intelligent fuzzy inference system approach for modeling the debonding strength of masonry elements retrofitted with Fiber Reinforced Polymer (FRP). To achieve this, the hybrid of meta-heuristic optimization methods and adaptive-network-based fuzzy inference system (ANFIS) is implemented. In this study, particle swarm optimization with passive congregation (PSOPC) and real coded genetic algorithm (RCGA) are used to determine the best parameters of ANFIS from which better bond strength models in terms of modeling accuracy can be generated. To evaluate the accuracy of the proposed PSOPC-ANFIS and RCGA-ANFIS approaches, the numerical results are compared based on a database from laboratory testing results of 109 sub-assemblages. The statistical evaluation results demonstrate that PSOPC-ANFIS in comparison with ANFIS-RCGA considerably enhances the accuracy of the ANFIS approach. Furthermore, the comparison between the proposed approaches and other soft computing methods indicate that the approaches can effectively predict the debonding strength and that their modeling results outperform those based on the other methods.

• Advances in nano research
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• v.13 no.5
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• pp.499-512
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• 2022

This study investigates the efficiency of ensemble machine learning for predicting the lightweight-aggregate concrete (LWC) characteristics. A stacking ensemble (STEN) approach was proposed to estimate the dry density (DD) and 28 days compressive strength (Fc-28) of LWC using two meta-models called random forest regressor (RFR) and extra tree regressor (ETR), and two novel ensemble models called STEN-RFR and STEN-ETR, were constructed. Four standalone machine learning models including artificial neural network, gradient boosting regression, K neighbor regression, and support vector regression were used to compare the performance of the proposed models. For this purpose, a sum of 140 LWC mixtures with 21 influencing parameters for producing LWC with a density less than 1000 kg/m³, were used. Based on the experimental results with multiple performance criteria, it can be concluded that the proposed STEN-ETR model can be used to estimate the DD and Fc-28 of LWC. Moreover, the STEN-ETR approach was found to be a significant technique in prediction DD and Fc-28 of LWC with minimal prediction error. In the validation phase, the accuracy of the proposed STEN-ETR model in predicting DD and Fc-28 was found to be 96.79% and 81.50%, respectively. In addition, the significance of cement, water-cement ratio, silica fume, and aggregate with expanded glass variables is efficient in modeling DD and Fc-28 of LWC.

• Journal of Distribution Science
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• v.22 no.5
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• pp.131-138
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• 2024

Purpose: This study aims to fill the existing gap in the existing literature by investigating the mediating effect of psychological empowerment between leadership and motivation for workers at retail stores, and to extend the previous research to determine the preferences of the researchers and practitioners in leadership and employee motivation in retail through a systematic approach. Research design, data and methodology: This study used a systematic approach to the mediation effect of psychological empowerment on the relationship between leadership and employee motivation in retail stores. To ensure completeness, systematization, and transparency, the preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach was applied. Results: The research findings (Total Four Mediating Roles) suggest that psychological empowerment may mediate between leadership and employee motivation. These mediation roles (Empowering Leadership Styles, Organizational Culture and Psychological Empowerment, Customer Psychological Empowerment, and High-Performance Work Systems (HPWS) and Psychological Empowerment) will help practitioners comprehend how these empowerment and motivation leadership styles are interconnected in the retail industry. Conclusions: The research results indicate that psychological empowerment is essential for employee motivation in the retail sector. Through this knowledge, retail store managers can implement strategies designed to empower employees and create a motivated workforce, bolstering organizational effectiveness.

• Journal of Korean Medicine for Obesity Research
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• v.17 no.1
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• pp.37-45
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• 2017

Recently the global epidemic problem of obesity has stimulated intense interest in the study of physiological mechanisms using animal models as a way to gain crucial data required for translation to human studies. Panax ginseng has been reported to have anti-obesity or antidiabetic effects in many animal studies; however, there have been few studies investigating human obesity. Herein, we will assess and examine the evidence supporting the anti-obesity effect of Panax ginseng in animal models with respect to anthropometric and metabolic outcomes. We will include controlled, comparative studies assessing the effect of Panax ginseng in preclinical studies of obesity. Panax ginseng will be administered during or following the induction of experimental obesity. The primary outcome measure will be anthropometric assessment and the secondary outcome measures will include adipose tissue weight, total amount of food consumed and metabolic parameters. We will search MEDLINE, Embase, PubMed, Web of Science, and Scopus without language, publication date, or other restrictions. Ethical approval will not be necessary as the data collected in this study will not be individual patient data, consequently there will be no concerns about violations of privacy. After finishing the whole procedure, the results will be disseminated by publication in a peer-reviewed journal or presented at a relevant conference. This protocol has been registered on the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES) website (http://www.camarades.info).

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.311-316
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• 2009

The purpose of this meta-analysis was to collect data from the literatures reporting prevalence of canine heartworm (HW) infection in an effort to emphasize the preventive importance of the disease and to serve as baseline data for further studies related to the disease management. Fourteen studies regarding the prevalence of HW infection published during the 1996-2007 were identified using the meta-analytic approach, involving a total of 1,790 cases by microfilarial test and 3,277 cases by enzyme-linked immunosorbent assay (ELISA) antigen test for adult worms. Data analysis was performed separately for pet and military dogs. The overall apparent prevalence of HW infection in pet dogs by microfilarial test and ELISA was 11.7% (183/1,563) and 16.5% (379/2,302), respectively (p < 0.001). No significant difference in prevalence by microfilaria and ELISA was observed between sexes whether assessed by data separately or pooled together. Compared to before 2000, the prevalence by microfilaria after 2000 has increased from 2.5% to 13.1% (p < 0.001), and the rate of adult worm has also increased from 9.9% to 20.3% (p < 0.001). The prevalence determined by ELISA was found to increase with age: 20.7% (n = 1,003) of dogs older than 2 years were positive, compared with 5.0% of dogs (n = 701) under 2 years of age (p < 0.001). Also, outdoor dogs showed significantly higher prevalence than indoor dogs (37.9% versus 3.4%; p < 0.001). For military dogs, the overall prevalence was 38.3% (87/227; 95% CI, 32.1 - 44.7%) by microfilarial test and 38.5% (375/975; 95% CI, 35.4 - 41.6%) by ELISA. This rate was significantly higher than that of pet dogs (p < 0.001). Occult infection rate of 37.5% and 66.7% was found in pet and military dogs, respectively.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.165-196
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• 2008

This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

• Journal of Gifted/Talented Education
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• v.26 no.1
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• pp.1-20
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• 2016

This study explored the cognitive characteristics and learning needs of economically disadvantaged gifted students. Gifted students(n=99), economically disadvantaged gifted students(n=43), and non-gifted students(n=50) participated in intelligence and creativity tests, and took self assessments of meta-cognition, epistemological beliefs, learning style preferences, and personal time usage. Superior abstract reasoning ability of economically disadvantaged gifted students was found because their scores on Raven's Test had risen rapidly compared to the other groups. Economically disadvantaged gifted students showed similar high scores as the gifted student on the Torrance Tests of Creativity Thinking-Figural, but not on Verbal. They were found to have a perception of the positive relationships among effort, learning abilities, and values of learning integrated knowledge with a general plan. However, they showed lower meta-cognitive control abilities than the gifted students in learning management and strategies, epistemological beliefs in value of rational operations, and time usage for learning. It is necessary to assign economically disadvantaged gifted students a task with various step by step methods of approach because these students prefer a new and creative task to difficult ones. Instruction plans such as developing language and meta-cognitive abilities and practical application of learning content was proposed.

• Journal of Korean Elementary Science Education
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• v.42 no.3
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• pp.434-454
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• 2023

This study explored the composition and attributes of modeling instructions and factors of teacher competence in elementary science classes. The study also examined educational research papers regarding modeling instruction cases in elementary schools and elementary teachers' perceptions of modeling instructions using qualitative meta-analysis, which can integrate findings from qualitative research. This investigation led to creating a small group to compose modeling instructions. Furthermore, the modeling approach was demonstrated to go through the process of generating, evaluating, and modifying the model. The attributes of modeling instructions can be divided into factors that affect modeling instructions and competence factors necessary for students participating in modeling instructions. The factors affecting modeling instructions included "small group interactions" and "time limitation in classes." The competence factors necessary for students participating in modeling instructions included "scientific knowledge," "meta-modeling knowledge," and the "ability to control emotions." The teacher competence factors in modeling instructions regarding knowledge, function, and attitude were explored. The teacher competence factors in elementary modeling instructions included "meta-modeling knowledge," "knowledge of modeling assessment," "emotional support for students," and the "awareness of modeling value." Accordingly, this study offered some recommendations for effective modeling instructions.