• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.4A
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• pp.399-414
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• 2004

In this paper, an evolution of software reliability engineering in a large-scale software project is summarized. The considered software consists of many components, called functional blocks in software of switching system. These functional blocks are served as the unit of coding and test, and the software is continuously updated by adding new functional blocks. We are mainly concerned with the analysis of the effects of these software components in software reliability and reliability evolution. We analyze the static characteristics of the software related to software reliability using collected failure data during system test. We also discussed a pattern which represents a local and global growth of the software reliability as version evolves. To find the pattern of system software, we apply the S-shaped model to a collection of failure data sets of each evolutionary version and the Goel-Okumoto(G-O) model to a grouped overall failure data set. We expect this pattern analysis will be helpful to plan and manage necessary human/resources fur a new similar software project which is developed under the same developing circumstances by estimating the total software failures with respect to its size and time.

• Food Science and Industry
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• v.51 no.1
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• pp.8-15
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• 2018

Functional food research has been struggling to demonstrate their beneficial effects in human, however, the physiological changes in humans who are in the target for functional food are very subtle and long term. In addition, it is difficult to obtain significant beneficial effect because of the necessity of using relatively healthy subjects. Relatively healthy subjects are homeostatic, and most of the biomarkers maintain a certain level under the "normal" or "resting" state. Moreover, due to wide inter-individual variation, it is difficult to detect significant changes. To address this problem, research has been actively conducted to identify the efficacy of natural products using 'omics' and 'bioinformatics' technology. In this review, we would like to introduce the human intervention studies applied homeostatic challenge model.

• Journal of Korea Planning Association
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• v.54 no.7
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• pp.5-23
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• 2019

The central government has implemented policies to strengthen the competitiveness of small and medium sized cities for balanced development at the national scale. However, since it is often difficult to enhance the competitiveness through partial projects of each jurisdiction, many local governments collaborate at the regional scale. This suggests that a regional approach is important for the management of small and medium sized cities. On the one hand, the concept of network city suggests that various functional networks can affect the growth of small and medium sized cities. Given this background, the purposes of this study are to delineate regional boundaries at national scale and identify their relations of growth by using functional network and Moran's I index. The study uses the Markov-chain model and cluster analysis to delineate the regions, and Moran's I is employed to identify the relations of growth. The results show that interactions between jurisdictions through networks could be crucial factors for growth of small and medium sized cities, while the networks based on passenger travel and freight movement have different implications. The results suggest that policy makers should not only consider local level investments, but also take the characteristics of networks between cities into account for achieving balanced development and developing regeneration policies.

• Communications for Statistical Applications and Methods
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• v.27 no.6
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• pp.603-624
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• 2020

There is an emerging interest in brain functional connectivity (FC) based on functional Magnetic Resonance Imaging in Alzheimer's disease (AD) studies. The complex and high-dimensional structure of FC makes it challenging to explore the association between altered connectivity and AD susceptibility. We develop a pipeline to refine FC as proper covariates in a penalized logistic regression model and classify normal and AD susceptible groups. Three different quantification methods are proposed for FC refinement. One of the methods is dimension reduction based on common component analysis (CCA), which is employed to address the limitations of the other methods. We applied the proposed pipeline to the Alzheimer's Disease Neuroimaging Initiative (ADNI) data and deduced pathogenic FC biomarkers associated with AD susceptibility. The refined FC biomarkers were related to brain regions for cognition, stimuli processing, and sensorimotor skills. We also demonstrated that a model using CCA performed better than others in terms of classification performance and goodness-of-fit.

• Journal of Korea Foundry Society
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• v.20 no.5
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• pp.330-335
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• 2000

Functional metal prototypes are often required in numerous industrial applications. These components are typically needed in the early stage of a project to determine form, fit and function. Recent R/P(Rapid Prototyping) part are made of soft materials such as plastics, wax, paper, these master models cannot be employed durable test in real harsh working environment. Parts by direct metal rapid tooling method, such as laser sintering, by now are hard to get net shape, pores of the green parts of powder casting method must be infiltrated to get proper strength as tool, and new type of 3D direct tooling system combining fabrication welding arc and cutting process is reported. But a system which can build directly 3D parts of high performance functional material as metal park would get long period of system development, massive investment and other serious obstacles, such as patent. In this paper, through the rapid tooling process as silicon rubber molding using R/P master model, and fabricate wax pattern in that silicon rubber mold using vacuum casting method, then we translated the wax patterns to numerous metal tool prototypes by new investment casting process combined conventional investment casting with rapid prototyping & rapid tooling process. With this wax-injection-mold-free investment casting, we developed new investment casting process of fabricating numerous functional metal prototypes from one master model, combined 3-D CAD, R/P and conventional investment casting and tried to expect net shape measuring total dimension shrinkage from R/P pare to metal part.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2252-2257
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• 2003

In this paper, we develop the so-called functional test model for magnetic bearing reaction wheels. The functional test model has three degree of freedom, which consists of one axial suspension from gravity and the other two axes gimbaling capability to small angle, and does not include the motor. For the control of the functional test model, we derive the optimal electromagnetic forces based on the least squares method, and use the proportional-integral-derivative controller. Then, we develop a hardware setup, which mainly consists of the digital signal processor and the 12-bit analog-to-digital and digital-to-analog converters, and show the experimental results.

• The Transactions of the Korea Information Processing Society
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• v.5 no.9
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• pp.2435-2446
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• 1998

In this paper. We describe a dataflow model for efficient execution of a functional logic language and a method of translation a functional logic language into a dataflow graph. To explore parallelism and intelligent backtracking, we us model in which clause and function are represented as independent dataflow graph. The node denotes basic actions to be performed when the clause and function are executed. The dataflow mechanism allows an operation to be executed as soon as all its operands are available. Since the operations can never be executed earlier, a dataflow model is an excellent base for increasing execution speed. We did decrease a delay time with concurrent execution of dependency analysis and subgoal.

• International Journal of Aeronautical and Space Sciences
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• v.4 no.2
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• pp.69-78
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• 2003

In this paper, we develop the so-called functional test model for magnetic bearing wheels. The functional test model developed in this paper is a kind of electromagnetic suspension systems and has three degree of freedom, which consists of one axial suspension from gravity and the other two axes gimbaling capability to small angle, and does not include the motor. For the control of the functional test model, we derive the optimal electromagnetic forces based on the least squares method, and use the proportional-integral derivative controller. Then, we develop a hardware setup, which mainly consists of the digital signal processor and the 12-bit analog-to-digital and digital-to-analog converters, and show the experimental results.

• Korean Journal of Child Studies
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• v.13 no.2
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• pp.145-160
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• 1992

The purpose of this study was to investigate the relationships between children's self-concepts and (1) types of functional family systems. (2) family cohesion and adaptability levels, and (3) the satisfaction of children with their current family systems. The subjects of this study were 347 middle S. E. S. children (168 boys, 179 girls) in grade 6. Analysis of functional family systems was by The Family Adaptability and Cohesion Evaluation Scales III(1985) of the Circuplex Model (Olson et al., 1979). The Self-concept Inventory (Lim Jae Leun, 1987) was used to assess children's self-concepts. The data were analyzed with one-way ANOVA, $Scheff{\acute{e}}$ and Pearson correlation. It was found that there were no differences in children's self-concepts by types of functional systems. There were differences in children's self-concepts by family cohesion and adaptability levels. That is, the higher the level of cohesion and adaptability the more positive the child's self-concept. The more the child was satisfied with his/her current family system, the more positive the child's self-concept. Children whose family systems were at a high level of family cohesion and adaptability were more satisfied with their current family systems.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.1
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• pp.183-194
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• 2018

This study investigated the characteristics of Omni Channel and examined the influence of them on consumers' perceived functional value and emotional value as well as the effect of perceived functional value and emotional value on user's intention of use through Omni Channel. To verify the research model, the questionnaire survey was conducted on 20's to 40's men and women residing in Seoul and the metropolitan area by convenience sampling. The number of copies used for data analysis was 696. To verify the research model, factor analysis, reliability analysis, and structural equation model analysis were performed using AMOS 20.0. First, Omni Channel characteristics consisted of four factors: instant connectivity, location-based provability, interactivity, and entertainment. Second, the instant connectivity, location-based provability and entertainment positively influenced functional value and emotional value; however, the interactivity was significant only to the emotional value. Third, consumers' perceived value of Omni Channel characteristics had a significant effect on attitude. Fourth, the more favorable the attitude toward Omni Channel is higher for the intention to use Omni Channel.