• Journal of Preventive Medicine and Public Health
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• 제15권1호
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• pp.179-186
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• 1982

The methods controlling the confounding factors were discussed using the data of secondary infertility with induced abortion. Mantel-Haenszel method and logistic model were applied in the analysis to find out which factors were confounding and/or effect modification variables. In the logistic analysis, the main effect of induced abortion, spontaneous abortion, age and interaction effect between induced abortion and spontaneous abortion were chosen as independent variables being regressed into logistic functions. Spontaneons abortion was interpreted as a potential confounder and at the same time potential effect modifier and age was interpreted as potential confounder. Spontaneous abortion was shown to be more important influencing factor than age to the secondary infertility. In the course of logistic analysis, the problem of parameter estimation and hypothesis testing, assessing the fitness of a model, and selection of the best model were briefly explained. For the program of logistic model, FUNCAT Procedure of SAS package was chosen.

• 소음진동
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• 제8권6호
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• pp.1113-1120
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• 1998

For an analysis of some Helmholtz resonators, it is likely to be more appropriate to consider acoustic field within cavity than just the 1-DOF analogous model. However, a design method that considers increased parameters than the lumped model. is not a trivial process due to the trade-off effect among the parameters. In this paper. the genetic algorithm. one of the optimization technique that rapidly converges to global fittest solution and robust convergence. is applied to the design process of Helmholtz resonators. Results show that the genetic algorithm can be successfully and efficiently used to find the resonant frequencies for both lumped model and distributed model.

• 경영과학
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• 제28권1호
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• pp.25-42
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• 2011

The mobile industry is the key foundation of digital convergence, and its constant growth is expected. Among mobile industries, new products leading the development of devices are the Emerging Device. This study is conducted to find out factors making differentiated by comparing the structural equation model(SEM) of the Tablet PC and the e-Book Reader. The main findings are as follows. First, the application of TAM to the Emerging Device shows that fitness of the model is generally high but the effect of Perceived Ease of Use has not been verified or found insignificant. Second, the acceptance model of the Tablet PC and the e-Book Reader has found that playfulness stimulates acceptance intentions. Third, the cost level of the Emerging Device acceptance model is not a factor stimulating consumers' acceptance intentions. Fourth, product attributes of the Tablet PC and the e-Book Reader to differentiate themselves from the other device are Functionality and Playfulness respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.292-294
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• 2000

This paper is presented the method peak load forecast based on multiple regression Model. Forecasting model was composed with the temperature-humidity and the discomfort index. Also the week periodicity was excluded from weekday change coefficient of two types. Forecasting result was good with about 3[%]. And, utility of presented forecast model using statistical tests has been proved. Therefore, This results establish appropriateness and fitness of forecast models using peak power demand forecasting.

• 반도체디스플레이기술학회지
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• 제12권1호
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• pp.1-7
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• 2013

Grey-level statistical models have been widely used in many applications for object location and identification. However, conventional models yield some problems in model refinement when training images are not properly aligned, and have difficulties for real-time recognition of arbitrarily rotated models. This paper presents improved grey-level statistical models that align training images using image or feature matching to overcome problems in model refinement of conventional models, and that enable real-time recognition of arbitrarily rotated objects using efficient hierarchical search methods. Edges or features extracted from a mean training image are used for accurate alignment of models in the search image. On the aligned position and orientation, fitness measure based on grey-level statistical models is computed for object recognition. It is demonstrated in various experiments in PCB inspection that proposed methods are superior to conventional methods in recognition accuracy and speed.

• 자원환경지질
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• 제28권4호
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• pp.425-431
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• 1995

Genetic algorithms are so named because they are analogous to biological processes. The model parameters are coded in binary form. The algorithm then starts with a randomly chosen population of models called chromosomes. The second step is to evaluate the fitness values of these models, measured by a correlation between data and synthetic for a particular model. Then, the three genetic processes of selection, crossover, and mutation are performed upon the model in sequence. Genetic algorithms share the favorable characteristics of random Monte Carlo over local optimization methods in that they do not require linearizing assumptions nor the calculation of partial derivatives, are independent of the misfit criterion, and avoid numerical instabilities associated with matrix inversion. An additional advantage over converntional methods such as iterative least squares is that the sampling is global, rather than local, thereby reducing the tendency to become entrapped in local minima and avoiding the dependency on an assumed starting model.

• International Journal of Aeronautical and Space Sciences
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• 제7권1호
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• pp.1-12
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• 2006

In this study, a surrogate model is applied to multi-objective aerodynamic optimization design. For the balanced exploration and exploitation, each objective function is converted into the Expected Improvement (EI) and this value is used as fitness value in the multi-objective optimization instead of the objective function itself. Among the non-dominated solutions about EIs, additional sample points for the update of the Kriging model are selected. The present method was applied to a transonic airfoil design. Design results showed the validity of the present method. In order to obtain the information about design space, two data mining techniques are applied to design results: Analysis of Variance (ANOVA) and the Self-Organizing Map (SOM).

• 대한가정학회지
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• 제40권9호
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• pp.175-189
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• 2002

The purpose of this study was to test a structural model about family income as causally related to family hardiness, pile-up stress, communication, and family adaptation in families of children with disabilities. 250 families of children with disabilities participated as subjects. The models were developed on the basis of confirmatory factor analysis and compared using covariance structure modeling(LISREL). Adequate fitness of the model was observed. Family income showed negative effect on pile-up stress and positive effect on family adaptation. Pile-up stress showed negative effect on family hardiness. Family hardiness showed positive effect on family communication, and family communication showed positive effect on family adaptation.

• Journal of Information Technology Applications and Management
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• 제13권2호
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• pp.145-162
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• 2006

Despite the careful attention paid by managers and researchers to the effective administration of the S/W Development Project, there are cases where the project goes over-budget or misses deadlines. Existing research blames these problems on task complexity or mismanagement. In order to verify the results that varied according to the fitness between the Task Characteristics and the Project Management Types, a contingency model was employed. The verification of the contingency model demonstrated that the greater the task complexity, the greater the effectiveness of the project coordination, and the lesser the task complexity, the greater the effectiveness of project control. This research is theoretically important in that it develops a composite model to verify the relation between the three factors of Task Characteristics, Project Management Types, and Project Performance that compose the S/W Development Project.

• Journal of Preventive Medicine and Public Health
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• 제46권sup1호
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• pp.35-42
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• 2013

A commitment to physical activity is necessary for personal health, and is a primary goal of physical activity practitioners. Effective practitioners rely on theory and research as a guide to best practices. Thus, sound theory, which is both practical and parsimonious, is a key to effective practice. The purpose of this paper is to review the literature in search of such a theory - one that applies to and explains commitment to physical activity in the form of sport and exercise for youths and adults. The Sport Commitment Model has been commonly used to study commitment to sport and has more recently been applied to the exercise context. In this paper, research using the Sport Commitment Model is reviewed relative to its utility in both the sport and exercise contexts. Through this process, the relevance of the Investment Model for study of physical activity commitment emerged, and a more parsimonious framework for studying of commitment to physical activity is suggested. Lastly, links between the models of commitment and individuals' participation motives in physical activity are suggested and practical implications forwarded.