• Korean Management Science Review
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• v.22 no.1
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• pp.15-26
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• 2005

The bootstrap is a method of computational inference that simulates the creation of new data by resampling from a single data set. We propose a new job for the bootstrap: generating inputs from one historical trace using Threshold Bootstrap. In this regard, the most important quality of bootstrap samples is that they be functionally indistinguishable from independent samples of the same stochastic process. We describe a quantitative measure of difference between two time series, and demonstrate the sensitivity of this measure for discriminating between two data generating processes. Utilizing this distance measure for the task of generating inputs, we show a way of tuning the bootstrap using a single observed trace. This application of the threshold bootstrap will be a powerful tool for Monte Carlo simulation. Monte Carlo simulation analysis relies on built-in input generators. These generators make unrealistic assumptions about independence and marginal distributions. The alternative source of inputs, historical trace data, though realistic by definition, provides only a single input stream for simulation. One benefit of our method would be expanding the number of inputs achieving reality by driving system models with actual historical input series. Another benefit might be the automatic generation of lifelike scenarios for the field of finance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.94-101
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• 1998

This paper presents the psychoacoustic analyses on the vehicle interior, noise generated when accelerating. Following the objective quantification for vehicle noises of different classes, the subjective decision process by the jury test is adopted to interrelate these results based on two different approaches. In particular, the paired comparison method is employed in assessing the sound quality in terms of the quietness, the powerfulness, and the pleasantness of the human auditory sensation. Special attention is paid to the physical interpretation of psychoacoutic parameters and their interrelation to the subjective assessment scores. In order to ensure the integrity of statistics of the survey, various tests are performed. The results show that the consistency of the "quiet" sensation is far higher than that of the "powerful" and the "pleasant" sensations. Also, it is found that the most significant parameter determining these feelings turns out to be the inherent loudness of the noise instead of the conventional indicators such as the weighted sound pressure level. It may be concluded that the psychoacoustic analysis offers more realistic evaluation for vehicle noise and assists the improvement of NVH more efficiently.ement of NVH more efficiently.

• Journal of KSNVE
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• v.8 no.2
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• pp.361-368
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• 1998

Complex and large lattice type structures are frequently used in design of bridge, tower, crane and aerospace structures. In general, in order to analyze these structures we have used the finite element method(FEM). This method is the most widely used and powerful tool for structural analysis. However, it is necessary to use a large amount of computer memory and computation time because the FEM resuires many degrees of freedom for solving dynamic problems exactly for these complex and large structures. For overcoming this problem, the authors developed the transfer stiffness coefficient method(TSCM). This method is based on the concept of the transfer of the nodal dynamic stiffness coefficient which is related to force and displacement vector at each node. In this paper, the authors formulate vibration analysis algorithm for a complex and large lattice type structure using the transfer of the nodal dynamic stiffness coefficient. And we confirmed the validity of TSCM through numerical computational and experimental results for a lattice type structure.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.154-154
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• 2001

2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin(TCDD), a prototype of many halogenated aromatic hydrocarbons, is a ubiquitous, persistent environmental contaminant and the most powerful carcinogen categorized by IARC. Despite extensive research, the mechanisms of TCDD-induced carcinogenesis are poorly understood, and its carcinogenic potential in human is not clear.(omitted)

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1073-1085
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• 2012

Soil microbial communities are immensely diverse and complex with respect to species richness and community size. These communities play essential roles in agricultural soil because they are responsible for most of the nutrient cycles in the soil and influence the plant diversity and productivity. However, the majority of these microbes remain uncharacterized because of poor culturability. Next-generation sequencing techniques have revolutionized many areas of biology by providing cheaper and faster alternatives to Sanger sequencing. Among them, amplicon pyrosequencing is a powerful tool developed by 454 Life Sciences for assessing the diversity of complex microbial communities by sequencing PCR products or amplicons. This review summarizes the current opinions in amplicon sequencing of soil microbial communities, and provides practical guidance and advice on sequence quality control, aligning, clustering, OTU- and taxon-based analysis. The last section of this article includes a few representative studies conducted using amplicon pyrosequencing.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.6
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• pp.899-909
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• 2015

TV home shopping maintains annual growth in the midst of harsh competition by numerous fashion retail channels. This study investigated the dimensions of service quality of TV home shopping for fashion products as well as the effect of service quality on relationship commitment and customer loyalty. Questionnaires were distributed to consumers in their 20s to 40s who purchased fashion products via TV home shopping in the past 6 months. A total of 240 questionnaires were put into the analysis. The results are as follows. First, four dimensions of service quality of TV home shopping were found: convenience, economy, entertainment, and information seeking. Relationship commitment had two dimensions of affective commitment and calculative commitment. Second, the service quality of TV home shopping affected customer loyalty through a relationship commitment. The predictors of affective commitment were entertainment, economy, and information seeking; in addition, those of calculative commitment were economy and entertainment. Third, both affective commitment and calculative commitment predicted customer loyalty to TV home shopping. The affective commitment had more predictive power. The findings show that the service quality of TV home shopping did not directly affect customer loyalty, but they had influence through relationship commitment variables. Entertainment and economy were the most powerful predictors among service quality dimensions.

• Environmental Engineering Research
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• v.14 no.1
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• pp.3-9
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• 2009

Microorganisms play an important role in the geochemical cycles, industry, environmental cleanup, and biotechnology among other fields. Given the high microbial diversity, identification of the microorganism is essential in understanding and managing the processes. One of the most popular and powerful method for microbial identification is comparative 16S rRNA gene analysis. Due to the highly conserved nature of this essential gene, sequencing and later comparison of it against known rRNA databases can provide assignment of the bacteria into the taxonomy, and the identity of its closest relatives. Isolation and sequencing of 16S rRNA genes directly from natural environments (either from DNA or RNA) can also be used to study the structure of the whole microbial community. Nowadays, novel sequencing technologies with massive outputs are giving researchers worldwide the chance to study the microbial world with a depth that was previously too expensive to achieve. In this article we describe commonly used research approaches for the study of individual microorganisms and microbial communities using the tools provided by Ribosomal Database Project website.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.05a
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• pp.210-215
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• 2007

In terms of cultural history, museum architecture represents culture of society in an era. exhibition space which represents the society and culture can't be fixed in the same way in a current mobile era. Especially, mobility of exhibition can be able to give audience even opportunities to enjoy. As a result, mobile exhibition space that functions as total space for everybody and the study of this issue is necessary. As mobile exhibition space is in the middle of development, there are many things to make up for the weak points. In order to make mobile exhibition space more competitive, development of new form and material is needed most. besides, limited development on interior plans which has been overlooked in terms of mobility is needed. Also, there should be more aggressive and powerful marketing and promotion for mobile exhibition space. To equalize the metropolitan area and local exhibition space and revitalize domestic exhibition space, the utility of mobile exhibition space which is movable and economic is highly expected more than previous fixed exhibition space.

• IE interfaces
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• v.10 no.1
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• pp.145-154
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• 1997

In developing the HMI(Human-Machine Interface) evaluation system for the IVNS(In-Vehicle Navigation System), design guidelines and evaluation methods are the most crucial problems for its use and efficiency. As the part of this system, focused on the final product of the database, subjective mental workload assessment is seriously considered to evaluate the driver's own driving task using the IVNS. This paper suggests the methodology for the ergonomic assessment of the IVNS that corresponds to the subjective measurement of the driver's mental workload by rating his or her own driving task. For this approach, Revision of NASA-Task Load Index(RNASA-TLX) was developed which translated and revised the version of NASA-TLX that is generally accepted an efficient and powerful method for evaluating the in-vehicle information systems. To verify the RNASA-TLX, an experiment was conducted in a real road situation, because the result of the laboratory approach is uncertain and has the differences from the real road test.

• Korean Journal of Human Ecology
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• v.11 no.2
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• pp.135-147
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• 2002

This study was to examine the differences in the levels of etiquette consciousness and performance of adolescents according to individual variables (sex, school, and self-esteem), family-related variables (parents' age and education level, and subjectively perceived living standard), and. etiquette-related variables (communication on etiquette, experience of etiquette education, parents' interest of and necessity. of etiquette education). The subjects were 394 middle and high school students in Jeonju. Such statistictical methods as t-test, F-test, Pearson's correlation analysis, and stepwise regression analysis were performed for this research. Results showed that the levels of etiquette consciousness and performance were slightly high. Among the domains of etiquette consciousness and performance, the levels of bowing manner and public etiquette were found to be relatively high. The etiquette consciousness and performance were different. according to adolescents' self-esteem, subjective living standard, and such etiquette variables as communication on etiquette, experience of etiquette education, parent's interest and necessity of etiquette education. Communication on etiquette was the most powerful variable influencing adolescents' etiquette performance. The results implied that the etiquette education need to be performed both in family and in school.