• Title/Summary/Keyword: Data Clustering

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Identification of Fuzzy Inference System Based on Information Granulation

  • Huang, Wei;Ding, Lixin;Oh, Sung-Kwun;Jeong, Chang-Won;Joo, Su-Chong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.4
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    • pp.575-594
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    • 2010
  • In this study, we propose a space search algorithm (SSA) and then introduce a hybrid optimization of fuzzy inference systems based on SSA and information granulation (IG). In comparison with "conventional" evolutionary algorithms (such as PSO), SSA leads no.t only to better search performance to find global optimization but is also more computationally effective when dealing with the optimization of the fuzzy models. In the hybrid optimization of fuzzy inference system, SSA is exploited to carry out the parametric optimization of the fuzzy model as well as to realize its structural optimization. IG realized with the aid of C-Means clustering helps determine the initial values of the apex parameters of the membership function of fuzzy model. The overall hybrid identification of fuzzy inference systems comes in the form of two optimization mechanisms: structure identification (such as the number of input variables to be used, a specific subset of input variables, the number of membership functions, and polyno.mial type) and parameter identification (viz. the apexes of membership function). The structure identification is developed by SSA and C-Means while the parameter estimation is realized via SSA and a standard least square method. The evaluation of the performance of the proposed model was carried out by using four representative numerical examples such as No.n-linear function, gas furnace, NO.x emission process data, and Mackey-Glass time series. A comparative study of SSA and PSO demonstrates that SSA leads to improved performance both in terms of the quality of the model and the computing time required. The proposed model is also contrasted with the quality of some "conventional" fuzzy models already encountered in the literature.

Literature Review and Network Analysis on the Pain Disease Approach of Saam Acupuncture Method (사암도인침법의 통증 질환 접근법에 대한 고찰)

  • Park, Ji-Yeun;Lee, Soon-Ho;Kim, Song-Yi;Park, Hi-Joon
    • Korean Journal of Acupuncture
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    • v.34 no.2
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    • pp.88-99
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    • 2017
  • Objectives : Saam acupuncture initiated by Saamdoin in $17^{th}$ century is one of the most widely adopted acupuncture techniques used by Korean medical doctors in clinic. Our study aimed to analyze the application of the Saam acupuncture method to pain diseases based on the literature data. Methods : Based on the contents described in "(Do Hae Kyo Kam) Saam's acupuncture method", the texts related to pain condition were analyzed. The frequency of prescription of Saam acupuncture method was analyzed, and then the relationships between each acupoint were visualized by network analysis and hierarchical cluster analysis for the quantitative aspect. Results and conclusions: In our study, Lung tonifying and Liver tonifying acupuncture were the most frequently used method for the treatment of pain disease. As the acupoints, BL66 and SI5 were used the most frequently. It was found that visceral pattern identification was considered as the most important factor in the selection of the Saam acupuncture method. Network analysis and hierarchical clustering analysis showed that each acupoint was closely related to other acupoints, and most of them were connected more closely according to the method of Saam acupuncture operation. The experiential prescriptions of Saam acupuncture were classified as an independent group. In the future, fundamental research on the principle of Saam acupuncture method is needed for the various diseases, and research for the clinical efficacy and the mechanism of Saam acupuncture method should be preceded.

Computer나 Calculator를 이용한 계산에서 오류 교정을 위한 어림셈 지도에 관한 연구

  • Gang Si Jung
    • The Mathematical Education
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    • v.29 no.1
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    • pp.21-34
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    • 1990
  • This is a study on an instruction of estimation for error correction in the calculation with a computer or a calculator. The aim of this study is to survey a new aspect of calaulation teaching and the teaching strategy of estimation and finally to frame a new curriculum model of estimation instruction. This research required a year and the outcomes of the research can be listed as follows: 1. Social utilities of estimation were made clear, and a new trend of calculation teaching related to estimation instruction was shown. 2. The definition of estimation was given and actual examples of conducting an estimation among pupils in lower grades were given for them to have abundant experiences. 3. The ways of finding estimating values in fraction and decimal fraction were presented for the pupils to be able to conduct an estimation. 4. The following contents were given as a basic strategy for estimation. 1) Front-end strategy 2) Clustering strategy 3) Rounding strategy 4) Compatible numbers strategy 5) Special numbers strategy 5. In an instuction of estimation the meaning, method. and process of calculation and calculating algorithm were reviewed for the cultivation of children's creativity through promoting their basic skill, mathematical thinking and problem-solving ability. 6. The following contents were also covered as an estimation strategy for measurement 1) Calculating the sense of quantity on the size of unit. 2) Estimating the total quantity by frequent repetition of unit quantity. 3) Estimating the length and the volume by weighing. 4) Estimating unknown quantity based on the quatity already known. 5) Estimating the area by means of equivalent area transformation. 7. The ways of instructing mental computation were presented. 8. Reviews were made on the curricular and the textbook contents concerning estimation instructions both in Korea and Japan. and a new model of curriculum was devised with reference to estimation instruction data of the United States.

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An Exploratory Study of Developing a Measurement Tool for the Quality of Information Commons (정보공유공간의 품질 측정지표 개발에 관한 탐색적 연구)

  • Park, Ji-Hong;Key, Sun-Ah
    • Journal of the Korean Society for Library and Information Science
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    • v.46 no.4
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    • pp.5-25
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    • 2012
  • The purpose of this study is to develop a measurement tool for the quality of information commons. Information commons is a physical, technological, social, and intellectual place where library users can experience various educational, research, and cultural activities. It is recently gaining popularity and several libraries have implemented it to help users share knowledge and interact with each other. It also intends to provide a place for collaboration, learning, and rest. Despite its benefits and usefulness, there is no measurement tool explicitly designed for the quality of information commons. This study used in-depth personal interview, compared prior studies, and conducted a pilot study to elicit library users' perceptions on information commons and factors influencing on the perceived quality of information commons. Groups of initial items were emerged through classifying and clustering key concepts in the data. Then, the validity of the items were verified through a pilot study. The findings of this study will be useful for developing more reliable and valid survey measurement tool.

Automatic Photovoltaic Panel Area Extraction from UAV Thermal Infrared Images

  • Kim, Dusik;Youn, Junhee;Kim, Changyoon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.6
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    • pp.559-568
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    • 2016
  • For the economic management of photovoltaic power plants, it is necessary to regularly monitor the panels within the plants to detect malfunctions. Thermal infrared image cameras are generally used for monitoring, since malfunctioning panels emit higher temperatures compared to those that are functioning. Recently, technologies that observe photovoltaic arrays by mounting thermal infrared cameras on UAVs (Unmanned Aerial Vehicle) are being developed for the efficient monitoring of large-scale photovoltaic power plants. However, the technologies developed until now have had the shortcomings of having to analyze the images manually to detect malfunctioning panels, which is time-consuming. In this paper, we propose an automatic photovoltaic panel area extraction algorithm for thermal infrared images acquired via a UAV. In the thermal infrared images, panel boundaries are presented as obvious linear features, and the panels are regularly arranged. Therefore, we exaggerate the linear features with a vertical and horizontal filtering algorithm, and apply a modified hierarchical histogram clustering method to extract candidates of panel boundaries. Among the candidates, initial panel areas are extracted by exclusion editing with the results of the photovoltaic array area detection. In this step, thresholding and image morphological algorithms are applied. Finally, panel areas are refined with the geometry of the surrounding panels. The accuracy of the results is evaluated quantitatively by manually digitized data, and a mean completeness of 95.0%, a mean correctness of 96.9%, and mean quality of 92.1 percent are obtained with the proposed algorithm.

Prevalence and Risk Factors of Mood Disorders among One University Freshmen (일 대학 신입생들의 기분장애 유병률과 위험요인)

  • Song, Jung-Hee;Min, Kyung-Jun;Park, Jung-Duck;Choi, Byung-Sun
    • Journal of the Korean Society of School Health
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    • v.22 no.2
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    • pp.169-181
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    • 2009
  • Purpose: Mood disorders such as depression and bipolar disorder are a major mental health problem in college students. We investigate the prevalence of depression and bipolar disorder and the relevance of risk factors for these mood disorders among one college freshmen. Methods: The subjects were 2,865 college students who entered one university located in Seoul and Ansung in 2009. We used BDI (Beck Depression Inventory) for depression assessment and K-MDQ (Mood Disorder Questionnaire) for bipolar disorder assessment. Demographic and socioeconomic factors were measured by questionnaire. Height, weight, blood pressure, total cholesterol, complete blood cell count, and liver function test data were obtained by physical examination for freshmen. Chi-square test and multiple logistic regression were performed to analyze the possible risk factors for depression and bipolar disorder. Results: With different BDI cutoff value, 16 and 21, the prevalence of depression was 8.7% (male: 7.6%, female: 10.1%) and 2.4% (male: 2.5%, female: 2.3%), separately. 'Low economic status', 'urban birth place', and 'low grade at entrance' were significantly associated with depression. Using the original cutoff criterion, defined as clustering of 7 or more symptoms that caused moderate or severe problems, the prevalence of bipolar disorder was 1.3% (male: 1.4%, female: 1.1%). The risk factor of bipolar disorder was academic fields (art fields). Conclusion: Depression and bipolar disorder are common disease in college freshmen. Therefore, Campus-based mental health service program is needed to help with prevention of and early intervention of these mood disorders.

Gene Expression Profiling of Early Renal Toxicity Induced by Gentamicin in Mice

  • Oh, Jung-Hwa;Park, Han-Jin;Lim, Jung-Sun;Jeong, Sun-Young;Hwang, Ji-Yoon;Kim, Yong-Bum;Yoon, Seok-Joo
    • Molecular & Cellular Toxicology
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    • v.2 no.3
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    • pp.185-192
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    • 2006
  • To elucidate the molecular mechanisms associated with early renal injury induced by gentamicin, the most commonly used antibiotics worldwide in the treatment of Gram-negative bacterial infections. We have identified genes differentially expressed at different duration of gentamicin administration. C57BL/6 female mice were treated daily with gentamicin (20 mg/kg, 100 mg/kg, and 200mg/kg) for 7 days and then sacrificed at day 1, 3, and 7 after administration. Standard blood biochemistry and histopathological observation indicative of nephrotoxicity were made. Total RNA was extracted from the kidney for microarray analysis using Affymetrix $GeneChip^{\circledR}$. Five hundred and seventy eight genes were identified as being either up-or down-regulated over 2-fold changes during early renal injury (p<0.05) and were analyzed by hierarchical clustering. The results showed that the genes involved in early immune responses were differentially regulated during early renal injury. Principal component analysis (PCA) confirmed sample separation according to the degree of renal toxicity. In addition, we identified two potential biomarkers that may predict early renal toxicity. This data may contribute to elucidate of the genetic events during early renal injury and to discover the potential biomarkers for nephrotoxicity induced by gentamicin.

A Unique Gene Expression Signature of 5-fluorouracil

  • Kim, Ja-Eun;Yoo, Chang-Hyuk;Park, Dong-Yoon;Lee, Han-Yong;Yoon, Jeong-Ho;Kim, Se-Nyun
    • Molecular & Cellular Toxicology
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    • v.1 no.4
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    • pp.248-255
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    • 2005
  • To understand the response of cancer cells to anticancer drugs at the gene expression level, we examined the gene expression changes in response to five anticancer drugs, 5-fluorouracil, cytarabine, cisplatin, paclitaxel, and cytochalasin D in NCI-H460 human lung cancer cells. Of the five drugs, 5-fluorouracil had the most distinctive gene expression signature. By clustering genes whose expression changed significantly, we identified three clusters with unique gene expression patterns. The first cluster reflected the up-regulation of gene expression by cisplatin, and included genes involved in cell death and DNA repair. The second cluster pointed to a general reduction of gene expression by most of the anticancer drugs tested. A number of genes in this cluster are involved in signal transduction that is important for communication between cells and reception of extracellular signals. The last cluster represented reduced gene expression in response to 5-fluorouracil, the genes involved being implicated in DNA metabolism, the cell cycle, and RNA processing. Since the gene expression signature of 5-fluorouracil was unique, we investigated it in more detail. Significance analysis of microarray data (SAM) identified 808 genes whose expression was significantly altered by 5-fluorouracil. Among the up-regulated genes, those affecting apoptosis were the most noteworthy. The down-regulated genes were mainly associated with transcription-and translation-related processes which are known targets of 5-fluorouracil. These results suggest that the gene expression signature of an anticancer drug is closely related to its physiological action and the response of caner cells.

Prediction of Soluble Solids Content of Chestnut using VIS/NIR Spectroscopy

  • Park, Soo Hyun;Lim, Ki Taek;Lee, Hoyoung;Lee, Soo Hee;Noh, Sang Ha
    • Journal of Biosystems Engineering
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    • v.38 no.3
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    • pp.185-191
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    • 2013
  • Purpose: The present study focused on the estimation of soluble solids content (SSC) of chestnut using reflectance and transmittance spectra in range of VIS/NIR. Methods: Four species intact/peeled chestnuts were used for acquisition of spectral data. Transmittance and reflectance spectra were used to develop the best PLS model to estimate SSC of chestnut. Results: The model developed with the transmitted energy spectra of peeled chestnuts rather than intact chestnuts and with range of NIR rather than VIS performed better. The best $R^2$ and RMSEP of cross validation were represented as 0.54 and $1.85^{\circ}Brix$. The results presented that the reflectance spectra of peeled chestnuts by species showed the best performance to predict SSC of chestnut. $R^2$ and RMSEP were 0.55 and $1.67^{\circ}Brix$. Conclusions: All developed models showed RMSEP around $1.44{\sim}2.54^{\circ}Brix$, which is considered not enough to estimate SSC accurately. It was noted that $R^2$ of cross validation that we found were not high. For all that, grading of the fruits in two or three classes of SSC during postharvest handling seems possible with an inexpensive spectrophotometer. Furthermore, the development of estimation of SSC by each chestnut species could be considered in that SSC distribution is clustering in different range by species.

Classification of Pollution Patterns in High School Classrooms using Disjoint Principal Component Analysis (분산주성분 분석을 이용한 고등학교교실 내 오염패턴분류에 관한 연구)

  • Jang, Choul-Soon;Lee, Tae-Jung;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.6
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    • pp.808-820
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    • 2006
  • In regard to indoor air quality patterns, the government introduced various polices that were about managing and monitoring quality of indoor air as a major assignment, and also executed 'Indoor Air Quality Management Act' which was presented in the May, 2004. However, among the multi-usage facilities controlled by the Act, the school was not included yet. This study goal was to investigate PM 10 pollution patterns of the high school classrooms using a pattern recognition method based on cluster analysis and disjoint principal component analysis, and further to survey levels of inorganic elements in May, June, and September, 2004. A hierarchical clustering method was examined to obtain possible objects in pseudo homogeneous sample classes by transformation raw data and by applying various distance. Following the analysis, the disjoint principal component analysis was used to define homogeneous sample class after deleting outliers. Then three homogeneous Patterns were obtained as follows: the first class had been separated and objects in the class were considered to be sampled under semi-open condition. This class had high concentration of Ca, Fe, Mg, K, Al, and Na which are related with a soil and a chalk compounds. The second class was obtained in which objects were sampled while working air-conditioners and was identified low concentration of PM 10 and elements. Objects in the last class were assigned during rainy day. A chalk, soil element and various types of anthropogenic sources including combustions and industrial influenced the third class. This methodology was thought to be helpful enough to classify indoor air quality patterns and indoor environmental categories when controlling an indoor air quality.