• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.1
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• pp.1-7
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• 2005

Cluster analysis of microarray data has been often used to find biologically relevant Broups of genes based on their expression levels. Since many functionally related genes tend to be co-expressed, by identifying groups of genes with similar expression profiles, the functionalities of unknown genes can be inferred from those of known genes in the same group. In this Paper we address a novel clustering approach, called seed clustering, and investigate its applicability for microarray data analysis. In the seed clustering method, seed genes are first extracted by computational analysis of their expression profiles and then clusters are generated by taking the seed genes as prototype vectors for target clusters. Since it has strong mathematical foundations, the seed clustering method produces the stable and consistent results in a systematic way. Also, our empirical results indicate that the automatically extracted seed genes are well representative of potential clusters hidden in the data, and that its performance is favorable compared to current approaches.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.2
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• pp.136-141
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• 2004

There has been enormous growth in the amount of commercial and scientific data, such as retail transactions, protein sequences, and web-logs. Such datasets consist of sequence data that have an inherent sequential nature. However, few clustering algorithms consider sequentiality. In this paper, we study how to cluster sequence datasets. We propose a new similarity measure to compute the similarity between two sequences. We also present an efficient method for determining the similarity measure and develop a clustering algorithm. Due to the high computational complexity of hierarchical clustering algorithms for clustering large datasets, a new clustering method is required. Therefore, we propose a new scalable clustering method using sampling and a k-nearest-neighbor method. Using a real dataset and a synthetic dataset, we show that the quality of clusters generated by our proposed approach is better than that of clusters produced by traditional algorithms.

• Journal of Communications and Networks
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• v.10 no.2
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• pp.137-147
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• 2008

This paper proposes a novel approach to interference avoidance via inter-cell relaying in cellular OFDMA-TDD (orthogonal frequency division multiple access - time division duplex) systems. The proposed scheme, termed asymmetry balancing, is targeted towards next-generation cellular wireless systems which are envisaged to have ad hoc and multi-hop capabilities. Asymmetry balancing resolves the detrimental base station (BS)-to-BS interference problem inherent to TDD networks by synchronizing the TDD switching points (SPs) across cells. In order to maintain the flexibility of TDD in serving the asymmetry demands of individual cells, inter-cell relaying is employed. Mobile stations (MSs) in a cell which has a shortage of uplink (UL) resources and spare downlink (DL) resources use free DL resources to off-load UL traffic to cooperating MSs in a neighboring cell using ad hoc communication. In an analogous fashion DL traffic can be balanced. The purpose of this paper is to introduce the asymmetry balancing concept by considering a seven-cell cluster and a single overloaded cell in the center. A mathematical model is developed to quantify the envisaged gains in using asymmetry balancing and is verified via Monte Carlo simulations. It is demonstrated that asymmetry balancing offers great flexibility in UL-DL resource allocation. In addition, results show that a spectral efficiency improvement of more than 100% can be obtained with respect to a case where the TDD SPs are adapted to the cell-specific demands.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.45-51
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• 2011

In this paper, we propose an unsupervised learning method for modeling motion trajectory patterns effectively. In our approach, observations of an object on a trajectory are treated as words in a document for latent dirichlet allocation algorithm which is used for clustering words on the topic in natural language process. This allows clustering topics (e.g. go straight, turn left, turn right) effectively in complex scenes, such as crossroads. After this procedure, we learn patterns of word sequences in each cluster using Baum-Welch algorithm used to find the unknown parameters in a hidden markov model. Evaluation of abnormality can be done using forward algorithm by comparing learned sequence and input sequence. Results of experiments show that modeling of semantic region is robust against noise in various scene.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.826-831
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• 1988

This paper presents an approach to segment an image into areas of surfaces, and to compute the surface properties from a gray-scale image in order to describe the surfaces for reconstruction of the 3-D shape of the objects. In general, an rigid body has several surfaces and many edges. But if it is not polyhedoron, it is necessary not only to describe the relation between surfaces, i.e. its line drawings but also to represent the surfaces' equations itself. In order to compute the surfaces' equation we use a probability of edge distribution. At first it is extracted edges from a gray-level image as much as possible. These are not only the points that maximize the change of an image intensuty but candidates which can be seemed to be edges. Next, other character of a surface (color, coordinates and image intensity) are extracted. In our study, we call the all feature of a surface as "texture", for example color, intensity level, orientation of an edge, shape of a surface and so on. These features of a surface on a pixel of an image plane are mapped to a point of the feature space, and segmented to each groups by cluster analysis on this space. These groups are considered to represent object surface in an image plane. Finally, the states of object surface in 3-D space are computed from distributional probability of local and overall statistical features of a surface, and from shape of a surface.a surface.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.125-125
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• 2017

The roots of Platycodon grandiflorum are commonly used for treating bronchitis, asthma, tuberculosis, diabetes, and other inflammatory diseases. Since the molecular mechanism underlying the roots of the plant is unclear. Therefore, the present study was conducted to profile proteins from liquid cultured tetraploid roots of Platycodon grandi orum fl using high throughput proteome approach. Two-dimensional gels stained with CBB, a total of 659 differentially expressed proteins were identified from the liquid medium cultured tetraploid roots of which 32 proteins spots (${\geq}1.5-fold$) were sorted for mass spectrometry analysis. Out of these 32 proteins, a total of 15 proteins were up-regulated such as Serine carboxypeptidase-like 27, Transcription factor bHLH150, 60 kDa jasmonate-induced protein, Cytosolic Fe-S cluster assembly factor NBP35, Regulatory associated protein of TOR 2 and a total of 17 proteins were down-regulated such as Protein G1-like2, Phenylalanine ammonia-lyase, Fructokinase-2, Trihelix transcription factor GT-3a, Guanine nucleotide-binding protein alpha-1 subunit. However, the frequency distribution of identified proteins was carried out within functional categories based on molecular functions, cellular components, and biological processes. Functional categorization revealed that the most of the identified proteins from the explants were mainly associated with the nucleic acid binding, oxidoreductase, transferase activity, protein binding and hydrolase activity. In addition, the proteomic feedback of tetraploid roots of P. grandiflorum may potentially be used to understand the characteristics of proteins and their functions.

• Health Policy and Management
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• v.20 no.2
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• pp.40-52
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• 2010

Health insurance fees are set by relative value scales and conversion factors. Since 2008 the conversion factor has been classified into 7 according to the provider type, and a separate contract has been made respectively. As such classification of the conversion factor reflects only the different characteristics of providers, however, further classification to reflect the different cost structures of providers is proposed. Cost varies according to the type of not only providers but also services each provider supply. In fact different cost structures of providers are the result of their different services. This study analyzed the cost structure of medical services to propose a new approach to the classification of the conversion factor. This study analyzed the cost structure of medical services using cost data constructed in the revision study of relative value scales. The cost data consist of doctor's fee, support staff's fee, cost of medical equipments, cost of medical supplies and indirect cost. The proportion of each cost component to the total cost was analyzed in terms of service department and service type. 72 service groups are defined in terms of the combination of service department and service type. Through cluster analysis, 72 service groups were reduced into 7 clusters each of which has a similar cost structure. Conversion factor is contracted annually to reflect the change in the cost of providing medical services. So the classification of conversion factor has to be based on the cost structures of medical services, not the characteristics of providers. Service clusters derived in this study can be used as a new classification for health insurance fee contract.

• Journal of the Korea Furniture Society
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• v.24 no.4
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• pp.433-443
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• 2013

The furniture industry of the northern region of Gyeonggi Province consists of several regional complexes which was just autogenously, that is, not based on the organized and planned movements cultivated and clustered, so it stays small businesses. This fact certainly requires to find right courses for future policy direction, in order to develop the furniture industry centering in the northern region of Gyeonggi Province internationally competitive. Consequently the aim of the present study was to investigate the characteristics of the furniture industry in the northern region of Gyeonggi Province first and to present right development directions for the innovation of the structure of furniture industry according to the change of the times, i.e. to connect the industry, university and the authorities concerned well and to strengthen the technology level of furniture industry accordingly. In addition, this requires education and training of the excellent designers being able to create high added-value industrial sectors, including finding a new Korean national brand which should preoccupy the global market. Furthermore, the high-tech furniture industrial complex specialized in manufacture, distribution and marketing such as the division of work between business to business should be built and finally a Korean traditional & unique furniture culture should be created on the basis of a cultural approach of furniture industry. It would be the timing for entire business sectors related to Korea's furniture industry to establish an international standard certification like ISO, in order to upgrade the quality of furniture steadily while keeping our own tradition, and this belongs to a meaningful attempt for the high-tech lifestyles and the improvement in the quality of life of customers.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.3
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• pp.279-289
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• 2017

Purpose: The purpose of this study is to investigate the learning experience, self-directed learning ability and self-efficacy of Japanese nursing students undergoing portfolio-based clinical practicums. Methods: The self-directed learning ability and self-efficacy of nursing students were examined using two scales. And using a text-mining approach, we constructed correspondence analysis followed by cluster analysis of open-ended responses forms. Results: The mean score of the self-directed learning ability was $60.89{\pm}5.28$ and the generalized self-efficacy was $68.37{\pm}11.56$. Moreover, the scores in the self-directed learning ability were positively correlated with scores in the generalized self-efficacy. In correspondence analysis, the distribution of extracted words showed that record was located on the negative side of the third quadrant, to the first principal component and that patient was located on the positive side of the first quadrant, contributing greatly to the second principal component. Conclusion: The results of this study contribute to approaching to "confidence, pride, stability," "growth and intention to development'' offers a key in developing self-directed learning ability. Students record what they see and learn the importance of visualizing it in learning portfolios. "Expression in detail of the learned contents" and "concerning to which objective evaluation is suggested" are important to the students.

• Clinical and Experimental Pediatrics
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• v.63 no.8
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• pp.321-328
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• 2020

Background: Pediatric hypertension is the main cause of morbidity and mortality in pediatric populations. Purpose: To examine pediatric hypertension in a clinical setting, we used the percentile rank approach and defined hypertension as that above the 95th percentile. Methods: The present study was linked to the a national analytical cross-sectional community-based Iranian Children and Adolescents' Psychiatric Disorders (IRCAP) survey. The survey was nationwide and funded by the National Institute of Medical Research Development. The IRCAP survey included 31,000 children and adolescents aged 6-18 years in all 31 Iran provinces. The current study included 1,035 children and adolescents and linked the data of the risk factors of cardiovascular disease only in Yazd province via random cluster sampling. Results: Of the total participants, 456 (44.1%) were male and 579 (55.9%) were female. The mean age was 11.2±3.8 years (11.7±3.7 years for males, 11.0±3.6 years for females), while mean height was 146±20.0 cm overall, 147.2±22.0 cm for males, and 144.6±17.0 cm for females (P=0.009). The blood pressure distributions and percentiles were evaluated. Conclusion: Here we determined age- and height-specific 50th, 90th, 95th, and 99th percentiles of systolic and diastolic blood pressures in Yazd boys and girls using 10-cm height intervals.