• Journal of the Korean Mathematical Society
• /
• v.45 no.3
• /
• pp.859-870
• /
• 2008

In the present paper, we investigate the geometric structures of the Dirichlet manifold composed of the Dirichlet distribution. We show that the Dirichlet distribution is an exponential family distribution. We consider its dual structures and give its geometric metrics, and obtain the geometric structures of the lower dimension cases of the Dirichlet manifold. In particularly, the Beta distribution is a 2-dimensional Dirich-let distribution. Also, we construct an affine immersion of the Dirichlet manifold. At last, we give the e-flat hierarchical structures and the orthogonal foliations of the Dirichlet manifold. All these work will enrich the theoretical work of the Dirichlet distribution and will be great help for its further applications.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.4
• /
• pp.355-359
• /
• 2014

In this paper, we proposed the new fuzzy pattern classifier which combines several fuzzy models with simple consequent parts hierarchically. The basic component of the proposed fuzzy pattern classifier with hierarchical structure is a fuzzy model with simple consequent part so that the complexity of the proposed fuzzy pattern classifier is not high. In order to analyze and divide the input space, we use Fuzzy C-Means clustering algorithm. In addition, we exploit Conditional Fuzzy C-Means clustering algorithm to analyze the sub space which is divided by Fuzzy C-Means clustering algorithm. At each clustered region, we apply a fuzzy model with simple consequent part and build the fuzzy pattern classifier with hierarchical structure. Because of the hierarchical structure of the proposed pattern classifier, the data distribution of the input space can be analyzed in the macroscopic point of view and the microscopic point of view. Finally, in order to evaluate the classification ability of the proposed pattern classifier, the machine learning data sets are used.

• Proceedings of the Korean Information Science Society Conference
• /
• 2007.06a
• /
• pp.143-144
• /
• 2007

• Communications for Statistical Applications and Methods
• /
• v.22 no.3
• /
• pp.265-276
• /
• 2015

In this paper, we propose hierarchical cluster analysis and multidimensional scaling for joint distribution valued data. Information technology is increasing the necessity of statistical methods for large and complex data. Symbolic Data Analysis (SDA) is an attractive framework for the data. In SDA, target objects are typically represented by aggregated data. Most methods on SDA deal with objects represented as intervals and histograms. However, those methods cannot consider information among variables including correlation. In addition, objects represented as a joint distribution can contain information among variables. Therefore, we focus on methods for joint distribution valued data. We expanded the two well-known exploratory methods using the dissimilarities adopted Hall Type relative projection index among joint distribution valued data. We show a simulation study and an actual example of proposed methods.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2007.05a
• /
• pp.1081-1083
• /
• 2007

The study in river basin has been performed for the identify water quality impaired stream segments, to create a priority ranking of those segments, and to calculate the heavy metal ion distribution for each impaired segment based on chemical and physical water quality standards. Two methods for modeling the potential area-specific heavy metal distribution are pursued in this study. First, a novel approach focuses on distance. Heavy metal distribution can be associated with a particular small geographic area. Based on the derived estimates an distribution map can be generated. Second, the approach is used the near watershed by means of kriging interpolation algorithm. These approaches provide an alternative distribution mapping of the area. The exposure estimates from both of these modeling methods are then compared with other environmental monitoring data. A GIS-based model will be used to mimic the hierarchical stream structure and processes found in natural watershed. Specifically, the relationship between landscape variables and reach scale habitat conditions most influential found in the Abandoned mine will be explored.

• Journal of Families and Better Life
• /
• v.26 no.5
• /
• pp.195-209
• /
• 2008

The purpose of this study was to provide basic information about design guidelines of activity areas in elderly nursing facilities. For the study, the activity areas of 44 facilities in Korea were investigated to categorize their spatial compositions and forms, and then a case study about 19 facilities was conducted to analyse their hierarchical characteristics. The results of the study were as follows: First, the major type of spatial composition among 44 research facilities was concentration, but compartment type was the main among unit-care facilities. By the year, all the types of spatial composition were evenly distributed during recent five years, while concentration type was about 40% before 2003. Second, the major form of activity areas was hall or corridor extension for large group. But there was more alcove or separation form among small group spaces. Third, in the case analysis about hierarchical characteristics, hall and corridor extension form met the requirements of accessibility and openness of public and semi-public areas. On the other hand, separation form had a problem in satisfying both requirements. The semi-private areas, which were around the elderly bedrooms and the elderly were able to watch activities in, were not sufficient in many facilities. Fourth, the division of public and semi-public area was mainly by furniture, and the individuality of semi-private area was defined by dead-end place and corner seats of the window or the corridor. The diversity of semi-private area was likely to be appeared in connection or distribution type. On the basis of the results, the basic design guidelines for activity areas in elderly nursing facilities could be suggested as follows: On the whole, connection or distribution type in spatial composition is more efficient for hierarchical flow than concentration or compartment type is, especially in Korean facilities having many elderly residents per floor. In detail, the design of public and semi-public area should be focused on their openness and accessibility. The recommended forms of activity areas were hall or corridor extension in public area, and living room, corridor extension, or large corridor in semi-public area to effectively function as large or small group spaces. In semi-private areas, the spatial diversity and individuality should be considered.

• Journal of the Korean Statistical Society
• /
• v.30 no.2
• /
• pp.179-192
• /
• 2001

When a statistical model has a hierarchical structure such as multilayer perceptrons in neural networks or Gaussian mixture density representation, the model includes distribution with unidentifiable parameters when the structure becomes redundant. Since the exact structure is unknown, we need to carry out statistical estimation or learning of parameters in such a model. From the geometrical point of view, distributions specified by unidentifiable parameters become a singular point in the parameter space. The problem has been remarked in many statistical models, and strange behaviors of the likelihood ratio statistics, when the null hypothesis is at a singular point, have been analyzed so far. The present paper studies asymptotic behaviors of the maximum likelihood estimator and the Bayesian predictive estimator, by using a simple cone model, and show that they are completely different from regular statistical models where the Cramer-Rao paradigm holds. At singularities, the Fisher information metric degenerates, implying that the cramer-Rao paradigm does no more hold, and that he classical model selection theory such as AIC and MDL cannot be applied. This paper is a first step to establish a new theory for analyzing the accuracy of estimation or learning at around singularities.

• Journal of Distribution Science
• /
• v.18 no.3
• /
• pp.53-65
• /
• 2020

Purpose: This study tests the suitability of a new technology acceptance model for a mobile payment system by checking how statistically significant the change is from the UTAUT (Unified Theory of Acceptance and Use of Technology) and UTAUT 2 models. Research, Data, and Methodology: We surveyed 250 students at Incheon University who are using the mobile payment system. The analysis was conducted on 243 valid questionnaires. The survey was conducted for one month in October 2018. The collected data were analyzed using SPSS and hierarchical regression analysis was applied. Results: Using hierarchical regression analysis, this study confirmed whether the newly added hedonic motivation, switching cost, and perceived risk variables in the UTAUT2 model are good explanatory variables. Mobile payment usage experience was found to have a moderating effect on mobile payment reuse intention. According to the analysis, the UTAUT2 model brought about more influential change than the variables of the UTAUT model. Conclusions: This study found that consumers' psychological factors added in the UTAUT2 model greatly influenced the reuse intention for mobile payment. As an implication of this study, mobile payment providers need to develop strategies that could meet hedonic motivation, switching cost and perceived risk for their customers.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2004.11a
• /
• pp.39-49
• /
• 2004

When there is a lack of detailed kinetic information, dFBA(dynamic flux balance analysis) has correctly predicted cellular behavior under given environmental conditions with FBA and different ial equations. However, until now, dFBA has centered on substrate concentration, cell growth, and gene on/off, but a detailed hierarchical structure of a regulatory network has not been taken into account. For this reason, the dFBA has limited the represen tation of interactions between specific regulatory proteins and genes and the whole transcriptional regulation mechanism with environmental change. Moreover, to calculate optimal metabolic flux distribution which maximizes the growth flux and predict the b ehavior of cell system, linear programming package(LINDO) and spreadsheet package(EXCEL) have been used simultaneously. thses two software package have limited in the visual representation of simulation results and it can be difficult for a user to look at the effects of changing inputs to the models. Here, we descirbes the construction of hierarchical regulatory network with defined symbolsand the development of an integrated system that can predict the total control mechanism of regulatory elements (opero ns, genes, effectors, etc.), substrate concentration, growth rate, and optimal flux distribution with time. All programming procedures were accoplished in a visual programming environment (LabVIEW).

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.5
• /
• pp.1257-1263
• /
• 1998

To realize a highly reliable satellite-base data distribution system efficiently, a hierarchical distributed control network which utilizers a sub control station(SCS) in addition to a hub and a user station(US) is proposed and evaluated. The results show that there exists an optimum number of sub control stations that minimizes the polling processing time as a parameter of the processing time ratio between US-SCS and SCS-CS links. From a viewpoint of the control network cost, it is shown that the cost can be less compared to the conventional one, when the communication cost between the US and SCS is slightly reduced.