• Title/Summary/Keyword: Clustering Technique

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Design and Implementation of Unified Index for Moving Objects Databases (이동체 데이타베이스를 위한 통합 색인의 설계 및 구현)

  • Park Jae-Kwan;An Kyung-Hwan;Jung Ji-Won;Hong Bong-Hee
    • Journal of KIISE:Databases
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    • v.33 no.3
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    • pp.271-281
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    • 2006
  • Recently the need for Location-Based Service (LBS) has increased due to the development and widespread use of the mobile devices (e.g., PDAs, cellular phones, labtop computers, GPS, and RFID etc). The core technology of LBS is a moving-objects database that stores and manages the positions of moving objects. To search for information quickly, the database needs to contain an index that supports both real-time position tracking and management of large numbers of updates. As a result, the index requires a structure operating in the main memory for real-time processing and requires a technique to migrate part of the index from the main memory to disk storage (or from disk storage to the main memory) to manage large volumes of data. To satisfy these requirements, this paper suggests a unified index scheme unifying the main memory and the disk as well as migration policies for migrating part of the index from the memory to the disk during a restriction in memory space. Migration policy determines a group of nodes, called the migration subtree, and migrates the group as a unit to reduce disk I/O. This method takes advantage of bulk operations and dynamic clustering. The unified index is created by applying various migration policies. This paper measures and compares the performance of the migration policies using experimental evaluation.

Microarray Analysis of Gene Expression in the Uterine Endometrium during the Implantation Period in Pigs

  • Kim, Min-Goo;Seo, Hee-Won;Choi, Yo-Han;Shim, Jang-Soo;Kim, Hee-Bal;Lee, Chang-Kyu;Ka, Hak-Hyun
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.8
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    • pp.1102-1116
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    • 2012
  • During embryo implantation in pigs, the uterine endometrium undergoes dramatic morphological and functional changes accompanied with dynamic gene expression. Since the greatest amount of embryonic losses occur during this period, it is essential to understand the expression and function of genes in the uterine endometrium. Although many reports have studied gene expression in the uterine endometrium during the estrous cycle and pregnancy, the pattern of global gene expression in the uterine endometrium in response to the presence of a conceptus (embryo/fetus and associated extraembryonic membranes) has not been completely determined. To better understand the expression of pregnancy-specific genes in the endometrium during the implantation period, we analyzed global gene expression in the endometrium on day (D) 12 and D15 of pregnancy and the estrous cycle using a microarray technique in order to identify differentially expressed endometrial genes between D12 of pregnancy and D12 of the estrous cycle and between D15 of pregnancy and D15 of the estrous cycle. Results showed that the global pattern of gene expression varied with pregnancy status. Among 23,937 genes analyzed, 99 and 213 up-regulated genes and 92 and 231 down-regulated genes were identified as differentially expressed genes (DEGs) in the uterine endometrium on D12 and D15 of pregnancy compared to D12 and D15 of the estrous cycle, respectively. Functional annotation clustering analysis showed that those DEGs included genes involved in immunity, steroidogenesis, cell-to-cell interaction, and tissue remodeling. These findings suggest that the implantation process regulates differential endometrial gene expression to support the establishment of pregnancy in pigs. Further analysis of the genes identified in this study will provide insight into the cellular and molecular bases of the implantation process in pigs.

Security Design for Efficient Detection of Misbehavior Node in MANET (MANET에서 비정상 노드를 효율적으로 탐지하기 위한 보안 설계)

  • Hwang, Yoon-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3B
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    • pp.408-420
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    • 2010
  • On a Mobile Ad hoc NETwork(MANET), it is difficult to detect and prevent misbehaviors nodes existing between end nodes, as communication between remote nodes is made through multiple hop routes due to lack of a fixed networked structure. Therefore, to maintain MANET's performance and security, a technique to identify misbehaving middle nodes and nodes that are compromise by such nodes is required. However, previously proposed techniques assumed that nodes comprising MANET are in a friendly and cooperative relationship, and suggested only methods to identify misbehaving nodes. When these methods are applied to a larger-scale MANET, large overhead is induced. As such, this paper suggests a system model called Secure Cluster-based MANET(SecCBM) to provide secure communication between components aperANET and to ensure eed. As such, this pand managems suapemisbehavior nodes. SecCBM consists apetwo stages. The first is the preventis pstage, whereemisbehavior nodes are identified when rANET is comprised by using a cluster-based hierarchical control structure through dynamic authentication. The second is the post-preventis pstage, whereemisbehavior nodes created during the course apecommunication amongst nodes comprising the network are dh, thed by using FC and MN tables. Through this, MANET's communication safety and efficiency were improved and the proposed method was confirmed to be suitable for MANET through simulation performance evaluation.

Visualization of Korean Speech Based on the Distance of Acoustic Features (음성특징의 거리에 기반한 한국어 발음의 시각화)

  • Pok, Gou-Chol
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.3
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    • pp.197-205
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    • 2020
  • Korean language has the characteristics that the pronunciation of phoneme units such as vowels and consonants are fixed and the pronunciation associated with a notation does not change, so that foreign learners can approach rather easily Korean language. However, when one pronounces words, phrases, or sentences, the pronunciation changes in a manner of a wide variation and complexity at the boundaries of syllables, and the association of notation and pronunciation does not hold any more. Consequently, it is very difficult for foreign learners to study Korean standard pronunciations. Despite these difficulties, it is believed that systematic analysis of pronunciation errors for Korean words is possible according to the advantageous observations that the relationship between Korean notations and pronunciations can be described as a set of firm rules without exceptions unlike other languages including English. In this paper, we propose a visualization framework which shows the differences between standard pronunciations and erratic ones as quantitative measures on the computer screen. Previous researches only show color representation and 3D graphics of speech properties, or an animated view of changing shapes of lips and mouth cavity. Moreover, the features used in the analysis are only point data such as the average of a speech range. In this study, we propose a method which can directly use the time-series data instead of using summary or distorted data. This was realized by using the deep learning-based technique which combines Self-organizing map, variational autoencoder model, and Markov model, and we achieved a superior performance enhancement compared to the method using the point-based data.

Transcriptional Profiling of Differentially Expressed Genes in Porcine Satellite Cell

  • Jeong, Jin Young;Kim, Jang Mi;Rajesh, Ramanna Valmiki;Suresh, Sekar;Jang, Gul Won;Lee, Kyung-Tai;Kim, Tae Hun;Park, Mina;Jeong, Hak Jae;Kim, Kyung Woon;Cho, Yong Min;Lee, Hyun-Jeong
    • Reproductive and Developmental Biology
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    • v.37 no.4
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    • pp.233-245
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    • 2013
  • Muscle satellite cell (SC) is responsible for postnatal muscle growth, repair, and regeneration. Satellite cell is an important source of multi-potent stem cell process and differentiation into adipogenic, myogenic, and osteoblastogenic. The objective of this study was to identify alter of transcriptome during differentiation in porcine satellite cell and to elevated transcriptome at different stages of postnatal development to gain insight into the differences in differentiated PSC. We used RNA-seq technique to investigate the transcriptomes during differentiation in pig muscle. Sequence reads were obtained from Illumina HiSeq2000. Differentially expressed genes (DEG) were detected by EdgeR. Gene ontology (GO) terms are powerful tool for unification among representation genes or products. In study of GO biological terms, functional annotation clustering involved in cell cycle, apoptosis, extracellular matrix, phosphorylation, proteolysis, and cell signaling in differences stage. Taken together, these results would be contributed to a better understanding of muscle biology and processes underlying differentiation. Our results suggest that the source of DEGs could be better understanding of the mechanism of muscle differentiation and transdifferentiation.

The study of the stereo X-ray system for automated X-ray inspection system using 3D-reconstruction shape information (3차원 형상복원 정보 기반의 검색 자동화를 위한 스테레오 X-선 검색장치에 관한 연구)

  • Hwang, Young-Gwan;Lee, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.8
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    • pp.2043-2050
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    • 2014
  • As most the scanning systems developed until now provide radiation scan plane images of the inspected objects, there has been a limitation in judging exactly the shape of the objects inside a logistics container exactly with only 2-D radiation image information. As a radiation image is just the density information of the scanned object, the direct application of general stereo image processing techniques is inefficient. So we propose that a new volume-based 3-D reconstruction algorithm. Experimental results show the proposed new volume based reconstruction technique can provide more efficient visualization for X-ray inspection. For validation of the proposed shape reconstruction algorithm using volume, 15 samples were scanned and reconstructed to restore the shape using an X-ray stereo inspection system. Reconstruction results of the objects show a high degree of accuracy compared to the width (2.56%), height (6.15%) and depth (7.12%) of the measured value for a real object respectively. In addition, using a K-Mean clustering algorithm a detection efficiency of 97% is achieved. The results of the reconstructed shape information using the volume based shape reconstruction algorithm provide the depth information of the inspected object with stereo X-ray inspection. Depth information used as an identifier for an automated search is possible and additional studies will proceed to retrieve an X-ray inspection system that can greatly improve the efficiency of an inspection.

Classifying a Strength of Dependency between classes by using Software Metrics and Machine Learning in Object-Oriented System (기계학습과 품질 메트릭을 활용한 객체간 링크결합강도 분류에 관한 연구)

  • Jung, Sungkyun;Ahn, Jaegyoon;Yeu, Yunku;Park, Sanghyun
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.10
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    • pp.651-660
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    • 2013
  • Object oriented design brought up improvement of productivity and software quality by adopting some concepts such as inheritance and encapsulation. However, both the number of software's classes and object couplings are increasing as the software volume is becoming larger. The object coupling between classes is closely related with software complexity, and high complexity causes decreasing software quality. In order to solve the object coupling issue, IT-field researchers adopt a component based development and software quality metrics. The component based development requires explicit representation of dependencies between classes and the software quality metrics evaluates quality of software. As part of the research, we intend to gain a basic data that will be used on decomposing software. We focused on properties of the linkage between classes rather than previous studies evaluated and accumulated the qualities of individual classes. Our method exploits machine learning technique to analyze the properties of linkage and predict the strength of dependency between classes, as a new perspective on analyzing software property.

Use of the Quantitatively Transformed Field Soil Structure Description of the US National Pedon Characterization Database to Improve Soil Pedotransfer Function

  • Yoon, Sung-Won;Gimenez, Daniel;Nemes, Attila;Chun, Hyen-Chung;Zhang, Yong-Seon;Sonn, Yeon-Kyu;Kang, Seong-Soo;Kim, Myung-Sook;Kim, Yoo-Hak;Ha, Sang-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.944-958
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    • 2011
  • Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

Genetic Diversity and Identification of Korean Grapevine Cultivars using SSR Markers (SSR마커를 이용한 국내육성 포도 품종의 다양성과 품종 판별)

  • Cho, Kang-Hee;Bae, Kyung-Mi;Noh, Jung Ho;Shin, Il Sheob;Kim, Se Hee;Kim, Jeong-Hee;Kim, Dae-Hyun;Hwang, Hae-Sung
    • Korean Journal of Breeding Science
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    • v.43 no.5
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    • pp.422-429
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    • 2011
  • This study was conducted to investigate the genetic diversity and to develop a technique for cultivar identification using SSR markers in grapevine. Thirty Korean bred and introduced grapevine cultivars were evaluated by 28 SSR markers. A total of 143 alleles were produced ranging from 2 to 8 alleles with an average of 5.1 alleles per locus. Polymorphic information contents (PIC) were ranged from 0.666 (VVIp02) to 0.975 (VVIn33 and VVIn62) with an average of 0.882. UPGMA (unweighted pair-group method arithmetic average) clustering analysis based on genetic distances using 143 alleles classified 30 grapevine cultivars into 7 clusters by similarity index of 0.685. Similarity values among the tested grapevine cultivars ranged from 0.575 to 1.00, and the average similarity value was 0.661. The similarity index was the highest (1.00) between 'Jinok' and 'Campbell Early', and the lowest (0.575) between 'Alden' and 'Narsha'. The genetic relationships among the 30 studied grapevine cultivars were basically consistent with the known pedigree. The three SSR markers sets (VVIn61, VVIt60, and VVIu20) selected from 28 primers were differentiated all grapevine cultivars except for 'Jinok' and 'Campbell Early'. Five cultivars ('Narsha, 'Alden', 'Dutchess', 'Pione', and 'Muscat Hamburg') were identified by VVIn61 at the first step. Then 21 cultivars including 'Hongsodam' by VVIt60 at the second step and 2 cultivars ('Heukbosuck' and 'Suok') by VVIu20 at the third step were identified. These markers could be used as a reliable tool for the identification of Korean grapevine cultivars.

Analysis of Genetic Relationships of Grapevine Cultivars (Vitis ssp.) in Korea Using RAPD Markers (RAPD를 이용한 한국 포도 품종의 계통유연관계 분석)

  • Yoo, Ki Yeol;Cho, Kang-Hee;Shin, Il-Sheob;Kim, Jeong Hee;Heo, Seong;Noh, Jung Ho;Kim, Hyun Ran
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.437-443
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    • 2009
  • In this study, we used the random amplified polymorphic DNA (RAPD) technique to evaluate the genetic relationships among 29 grapevine cultivars (Vitis spp.). Sixty selective primers detected a total of 558 polymorphic bands. By UPGMA (unweighted pair-group method arithmetic average) cluster analysis with 558 polymorphic bands, the 29 grapevine cultivars were divided into six major groups at 58.8% genetic similarity. The "Super Hamburg" was clustered in group I. Group II consisted of "Wonkyo RA-23", "Muscat Hamburg", "Tano Red", and "Tankeumchu". Group III consisted of "Alden", "Wonkyo RA -21", "Wonkyo RA-30", and "Dutchess". Group IV included 14 grapevine cultivars ("Heukgoosul", "Heukbosuk", "Suok", "Wonkyo RA-29", "Wonkyo RA-22", "Kyoho", "Pione", "Beniizu", "Golden Muscat", "Jinok", "Doonuri", "Campbell Early", "Delaware", and "Schuyler"). Group V consisted of "Hongdan", "Tamnara", "Hongisul", and "Himrod seedless". Group VI included 2 cultivars ("Cheongsoo", and "S. 9110").