• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.710-715
• /
• 2004

The design problem of manufacturing system is addressed, adopting the closed queueing network model with multiple loops and re-entrant flows. The entire design problem is divided into two hierarchical sub-problems of (1) determining the station configuration and (2) optimizing the lot constitution; then they are tackled by neighbor search algorithm (NSA) and greedy mean value analysis (GMVA), respectively. Unlike the conventional MVA concerning multi-class closed queueing networks, the GMVA doesn't stick to a fixed lot proportion; rather it tries to find the optimal balance. The NSA, on the other hand, improves the object function value by altering the station configuration successively with its superior neighbor. The moderate time complexity, presented in big-${o}$ notation, enables us to apply the method even to the large-size practical cases, and the CPU time of an enlarged problem can be approximated by the same equation. The validity of our analytic approach is backed up by simulation studies with a widespread simulation package.

• Journal of Korean Society for Atmospheric Environment
• /
• v.13 no.1
• /
• pp.51-63
• /
• 1997

Total suspended particulate matters in the ambient air were analyzed for eight chemical elements (Ca, Co, Cu, Fe, Mn, Pb, Si, and Zn) using an x-ray fluorescence spectrometry (XRF) at the Kyung Hee University - Suwon Campus during 1989 to 1994. To use these data as basis for source identification study, membership of each sample was selected to represent one of the well defined sample groups. The data sets consisting of 83 objects and 8 variables were initially separated into two groups, fine (d$_{p}$<3.3 ${\mu}{\textrm}{m}$) and coarse particle groups (d$_{p}$>3.3 ${\mu}{\textrm}{m}$). A hierarchical clustering method was examined to obtain possible member of homogeneous sample classes for each of the two groups by transforming raw data and by applying various distances. A disjoint principal component analysis was then used to define homogeneous sample classes after deleting outliers. Each of five homogeneous sample classes was determined for the fine and the coarse particle group, respectively. The data were properly classified via an application of logarithmic transformation and Euclidean distance concept. After determining homogeneous classes, correlation coefficients among eight chemical variables within all the homogeneous classes for calculated and meteorological variables (temperature. relative humidity, wind speed, wind direction, and precipitation) were examined as well to intensively interpret environmental factors influencing the characteristics of each class for each group. According to our analysis, we found that each class had its own distinct seasonal pattern that was affected most sensitively by wind direction.ion.

• The Journal of the Korea Contents Association
• /
• v.8 no.1
• /
• pp.169-176
• /
• 2008

In this paper, we develop radio resource management queueing model in IEEE 802.IS networks considering both connection and packet level. In the upper level connection, we model connection admission control depending on availability of bandwidth and priority queue in each service class. In the lower level packet, we model dynamic bandwidth allocation considering threshold and availability of bandwidth in each service class simultaneously. Hierarchical model is built using an extended Petri Nets, SRN (Stochastic Reward Nets). Bandwidth utilization and normal throughput as performance index for all service classes of traffic are calculated and numerical results are obtained.

• Proceedings of the KSRS Conference
• /
• 2008.03a
• /
• pp.195-200
• /
• 2008

The accuracy of classifying pixels in HIRIS images is usually degraded by noisy bands since noisy bands may deform the typical shape of spectral reflectance. Proposed in this paper is a statistical method for noisy band removal which mainly makes use of the correlation coefficients between bands. Considering each band as a random variable, the correlation coefficient measures the strength and direction of a linear relationship between two random variables. While the correlation between two signal bands is high, existence of a noisy band will produce a low correlation due to ill-correlativeness and undirectedness. The application of the correlation coefficient as a measure for detecting noisy bands is under a two-pass screening scheme. This method is independent of the prior knowledge of the sensor or the cause resulted in the noise. The classification in this experiment uses the unsupervised k-nearest neighbor algorithm in accordance with the well-accepted Euclidean distance measure and the spectral angle mapper measure. This paper also proposes a hierarchical combination of these measures for spectral matching. Finally, a separability assessment based on the between-class and within-class scatter matrices is followed to evaluate the performance.

• Korean Journal of Health Education and Promotion
• /
• v.31 no.1
• /
• pp.27-43
• /
• 2014

Objectives: The purpose of this study was to evaluate depression of mothers with children in early childhood and to identify predictors by income level. Methods: The research was conducted with 1,761 data from the 3rd wave of the Panel Study of Korean Children(PSKC) data. Independent variables were socio-demographic data, self-esteem, normative life-events, non-normative life events, parenting stress, marital conflict, social support. Data were analyzed by t-test, ANOVA, hierarchical multiple regression analysis were conducted. Results: Significant factors of depression of female in low-income were non-normative life events, parenting stress, marital conflict. In middle class, significant factors were education, birth order of children, self-esteem, normative and non-normative life events, parenting stress, marital conflict, sociable support. At last, we found that marital conflict was the biggest factor for depression of female in low-income and parenting stress was the most powerful predictor in middle class. Conclusions: Mother's depression has a enormous impacts on development of children in early childhood. Therefore It is required to prevent depression in mothers and it is important to intervene at the early stage of depression. Results of this study showed a different pattern of predictors by income level. Therefore, Intervention and services for a mother's depression should change the direction depending on the level of income.

• Proceedings of the Zoological Society Korea Conference
• /
• 1997.10a
• /
• pp.42-57
• /
• 1997

The multicriterion matrix technique (MM-technique) was proposed for a method of monitoring and assessment about vegetation naturalness. Four criteria and 10 subcriteria were selected and two evaluation indices such as VN-value and VN-class were used. The criteria were characterized by syntaxonomical informations of hemeroby concept and potential natural vegetation, hierarchical system between criteria, and ordinal scale of VN-values. VN-values were classified into 11 ordinal levels and condensed to five VN-classes for facilitating practical use. A vegetation map of naturalness described by combination o( two indices was proposed as an alternative resolution of the DGN map. We also discuss the organization of the map content which is a matter of grid size (unit-area). In the case study, a grid size proper to show a full account of real information of actual vegetation is less 250-grid (250 $\times$ 250 $m^2$) in a medium size of city area containing relatively fragmented ecosystems. In conclusion, it was recognized that this new assessment technique was useful and vegetation assessment was accomplished with the smaller grid size in Korea.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.47 no.2
• /
• pp.232-243
• /
• 2023

The boundaries between fashion and contemporary art are increasingly blurred showing their interchangeability. This study examines Judith Butler and Athena Athanasiou's concept of dispossession to analyze expressions of gender, racial, and class identity in Martine Gutierrez's representative work, Indigenous Woman. First, gender expressions in Indigenous Woman emphasize the possibility of performative and practical gender as an image that rejects norms that grant authority according to the possession of innate body parts. Second, racial identity is expressed through resistance to the ideology of whiteness and imperialism reinforced by fashion media. The author aims to overcome normative stereotypes through the media she creates, which reveals her identity as a person of color. Third, class identity is represented through stereotypes that limit the lives of indigenous people to primitive and natural things. The author reveals a critical awareness of the hierarchical structure and cultural appropriation these stereotypes have created. This study analyzed contemporary artworks using fashion media through the concept of dispossession. The significance of this study lies in raising a critical awareness of the practices that diffuse minority identities in fashion media.

• The KIPS Transactions:PartB
• /
• v.16B no.4
• /
• pp.281-288
• /
• 2009

This paper proposes a novel algorithm for the efficient classification and annotation of medical images, especially X-ray images. Since X-ray images have a bright foreground against a dark background, we need to extract the different visual descriptors compare with general nature images. In this paper, a Color Structure Descriptor (CSD) based on Harris Corner Detector is only extracted from salient points, and an Edge Histogram Descriptor (EHD) used for a textual feature of image. These two feature vectors are then applied to a multi-class Support Vector Machine (SVM), respectively, to classify images into one of 20 categories. Finally, an image has the Annotation Code Array based on the pre-defined hierarchical relations of categories and priority code order, which is given the several optimal keywords by the Annotation Code Array. Our experiments show that our annotation results have better annotation performance when compared to other method.

• The Korean Journal of Applied Statistics
• /
• v.29 no.5
• /
• pp.961-975
• /
• 2016

The hierarchically penalized support vector machine (H-SVM) has been developed to perform simultaneous classification and input variable selection when input variables are naturally grouped or generated by factors. However, the H-SVM may suffer from estimation inefficiency because it applies the same amount of shrinkage to each variable without assessing its relative importance. In addition, when analyzing imbalanced data with uneven class sizes, the classification accuracy of the H-SVM may drop significantly in predicting minority class because its classifiers are undesirably biased toward the majority class. To remedy such problems, we propose the weighted adaptive H-SVM (WAH-SVM) method, which uses a adaptive tuning parameters to improve the performance of variable selection and the weights to differentiate the misclassification of data points between classes. Numerical results are presented to demonstrate the competitive performance of the proposed WAH-SVM over existing SVM methods.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.20 no.3
• /
• pp.149-161
• /
• 2009

The purpose of this study is to investigate and analyse the revised contents of the history class in the Korean Decimal Classification(KDC), 5th edition, and then identify problems and propose the revised contents for the KDC, 6the edition. Major analysed areas are divided into four. First, geographic area table is discussed. It includes extension of the geographic area table, emphasis of hierarchical structure in the geographical area, revision of North Korean geographical names, extension of subgeographical structure of major nations in the world, and revision of nations in the central and west Asia. Second, Korean time period is extended. Third, the notes of entries of the Chinese and Japanese history areas are shorten. Fourth, the geographical and personal names are changed their native pronunciation, specially Chinese and Japanese. For the revision of the KDC, 6th edition, four areas are discussed: first, Korean geographic areas would be categorized by broaden area, second, the areas are arranged from the capital of the nation to others, third, foreign geographical names would be used their native names, and last, time period would be categorized by years.