• Title/Summary/Keyword: Cluster-based Network

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A Robust Pair-wise Key Agreement Scheme based on Multi-hop Clustering Sensor Network Environments (멀티홉 클러스터 센서 네트워크 환경 기반에서 견고한 키 교환)

  • Han, Seung-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.251-260
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    • 2011
  • In this paper, we proposed a scheme that it safely exchanges encrypted keys without Trust Third Party (TTP) and Pre-distributing keys in multi-hop clustering sensor networks. Existing research assume that it exists a TTP or already it was pre-distributed a encrypted key between nodes. However, existing methods are not sufficient for USN environment without infrastructure. Some existing studies using a random number Diffie-Hellman algorithm to solve the problem. but the method was vulnerable to Replay and Man-in-the-middle attack from the malicious nodes. Therefore, authentication problem between nodes is solved by adding a ��TESLA. In this paper, we propose a modified Diffie-Hellman algorithm that it is safe, lightweight, and robust pair-wise agreement algorithm by adding One Time Password (OTP) with timestamp. Lastly, authentication, confidentiality, integrity, non-impersonation, backward secrecy, and forward secrecy to verify that it is safe.

The Evaluation of Web Contents by User 'Likes' Count: An Usefulness of hT-index for Topic Preference Measurement

  • Song, Yeseul;Park, Ji-Hong;Shim, Jiyoung
    • Journal of the Korean Society for Library and Information Science
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    • v.49 no.2
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    • pp.27-49
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    • 2015
  • The purpose of this study is to suggest an appropriate index for evaluating preferences of Web contents by examining the h-index and its variants. It focuses on how successfully each index represents relative user preference towards topical subjects. Based on data obtained from a popular IT blog (engadget.com), subject values of the h-index and its variants were calculated using 53 subject categories, article counts and the 'Likes' counts aggregated in each category. These values were compared through critical analysis of the indices and Spearman rank correlation analysis. A PFNet (Pathfinder Network) of subjects weighted by $h_T$ values was drawn and cluster analysis was conducted. Based on the four criteria suggested for the evaluation of Web contents, we concluded that the $h_T$-index is a relatively appropriate tool for the Web contents preference evaluation. The $h_T$-index was applied to visually represent the relative weight (topic preference by user 'Likes' count) for each subject category of the real online contents after suggesting the relative appropriateness of the $h_T$-index. Applying scientometric indicators to Web information could provide new insights into, and potential methods for, Web contents evaluation. In addition, information on the focus of users' attention would help online informants to plan more effective content strategies. The study tries to expand the application area of the h-type indices to non-academic online environments. The research procedure enables examination of the appropriateness of the index and highlights considerations for applying the indicators to Web contents.

A Study on Acupoint SP3 in Saam Acupuncture Method (사암도인침법에서 태백혈의 운용에 대한 연구)

  • Kim, Song-Yi;Lee, Soon-Ho;Park, Ji-Yeun;Park, Hi-Joon
    • Korean Journal of Acupuncture
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    • v.31 no.4
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    • pp.179-187
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    • 2014
  • Objectives : Saam acupuncture initiated by Saamdoin is traditional and originative method, which is characterized by applying the five phases theory and mother-child reinforcement-reduction principle to the selection of acupoints and needling manipulation. Our study was aimed to summarize and assess the use of acupoint SP3(Taebaek) in Saam acupuncture treatment and to further understand Saam acupuncture in an aspect of the combination of acupoints. Methods : We searched the data based on "(Do Hae Kyo Kam) Sa-Ahm's acupuncture method" for SP3 used and acupoint combination including SP3. We performed frequency analysis, network analysis, and cluster analysis for quantitative aspect. To understand clinical implication of SP3 with another acupoint, qualitative and descriptive methods were also carried out. Results and Conclusions : In our study, SP3 was frequently used for tonification of lung, spleen, heart, and kidney meridian and sedation of kidney, heart, and lung meridian. For this, many acupoints such as LU8, LU9, KI3, HT8, KI7, LU10 and LR1 were used with SP3. The combination of SP3 and other acupoints were used to treat stroke, common cold, and pain conditions including headache, low back pain, respiratory disease as well as gastroenteric troubles including stomachache, indigestion, vomiting, and constipation. To further understand Saam acupuncture, an understanding of the five transport points based on five elements characters, pathological changes (deficiency and excess) of viscera and bowels, and concept of source point should be preceded.

Draft Design of AI Services through Concept Extension of Connected Data Architecture (Connected Data Architecture 개념의 확장을 통한 AI 서비스 초안 설계)

  • Cha, ByungRae;Park, Sun;Oh, Su-Yeol;Kim, JongWon
    • Smart Media Journal
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    • v.7 no.4
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    • pp.30-36
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    • 2018
  • Single domain model like DataLake framework is in spotlight because it can improve data efficiency and process data smarter in big data environment, where large scaled business system generates huge amount of data. In particular, efficient operation of network, storage, and computing resources in logical single domain model is very important for physically partitioned multi-site data process. Based on the advantages of Data Lake framework, we define and extend the concept of Connected Data Architecture and functions of DataLake framework for integrating multiple sites in various domains and managing the lifecycle of data. Also, we propose the design of CDA-based AI service and utilization scenarios in various application domain.

Gene Expression Patterns Associated with Peroxisome Proliferator-activated Receptor (PPAR) Signaling in the Longissimus dorsi of Hanwoo (Korean Cattle)

  • Lim, Dajeong;Chai, Han-Ha;Lee, Seung-Hwan;Cho, Yong-Min;Choi, Jung-Woo;Kim, Nam-Kuk
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.8
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    • pp.1075-1083
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    • 2015
  • Adipose tissue deposited within muscle fibers, known as intramuscular fat (IMF or marbling), is a major determinant of meat quality and thereby affects its economic value. The biological mechanisms that determine IMF content are therefore of interest. In this study, 48 genes involved in the bovine peroxisome proliferator-activated receptor signaling pathway, which is involved in lipid metabolism, were investigated to identify candidate genes associated with IMF in the longissimus dorsi of Hanwoo (Korean cattle). Ten genes, retinoid X receptor alpha, peroxisome proliferator-activated receptor gamma (PPARG), phospholipid transfer protein, stearoyl-CoA desaturase, nuclear receptor subfamily 1 group H member 3, fatty acid binding protein 3 (FABP3), carnitine palmitoyltransferase II, acyl-Coenzyme A dehydrogenase long chain (ACADL), acyl-Coenzyme A oxidase 2 branched chain, and fatty acid binding protein 4, showed significant effects with regard to IMF and were differentially expressed between the low- and high-marbled groups (p<0.05). Analysis of the gene co-expression network based on Pearson's correlation coefficients identified 10 up-regulated genes in the high-marbled group that formed a major cluster. Among these genes, the PPARG-FABP4 gene pair exhibited the strongest correlation in the network. Glycerol kinase was found to play a role in mediating activation of the differentially expressed genes. We categorized the 10 significantly differentially expressed genes into the corresponding downstream pathways and investigated the direct interactive relationships among these genes. We suggest that fatty acid oxidation is the major downstream pathway affecting IMF content. The PPARG/RXRA complex triggers activation of target genes involved in fatty acid oxidation resulting in increased triglyceride formation by ATP production. Our findings highlight candidate genes associated with the IMF content of the loin muscle of Korean cattle and provide insight into the biological mechanisms that determine adipose deposition within muscle.

Implementation of the ZigBee-based Homenetwork security system using neighbor detection and ACL (이웃탐지와 ACL을 이용한 ZigBee 기반의 홈네트워크 보안 시스템 구현)

  • Park, Hyun-Moon;Park, Soo-Hyun;Seo, Hae-Moon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.1
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    • pp.35-45
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    • 2009
  • In an open environment such as Home Network, ZigBee Cluster comprising a plurality of Ato-cells is required to provide intense security over the movement of collected, measured data. Against this setting, various security issues are currently under discussion concerning master key control policies, Access Control List (ACL), and device sources, which all involve authentication between ZigBee devices. A variety of authentication methods including Hash Chain Method, token-key method, and public key infrastructure, have been previously studied, and some of them have been reflected in standard methods. In this context, this paper aims to explore whether a new method for searching for neighboring devices in order to detect device replications and Sybil attacks can be applied and extended to the field of security. The neighbor detection applied method is a method of authentication in which ACL information of new devices and that of neighbor devices are included and compared, using information on peripheral devices. Accordingly, this new method is designed to implement detection of malicious device attacks such as Sybil attacks and device replications as well as prevention of hacking. In addition, in reference to ITU-T SG17 and ZigBee Pro, the home network equipment, configured to classify the labels and rules into four categories including user's access rights, time, date, and day, is implemented. In closing, the results demonstrates that the proposed method performs significantly well compared to other existing methods in detecting malicious devices in terms of success rate and time taken.

Protocol implementation for simultaneous signal continuation acquisition of industrial plant machine condition in wireless sensor networks (산업플랜트 기계상태 동시신호 연속취득을 위한 무선센서 네트워크프로토콜 구현)

  • Lee, Hoo-Rock;Chung, Kyung-Yul;Rhyu, Keel-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.7
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    • pp.760-764
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    • 2015
  • Wireless sensors, installed on machinery, and Time Division Multiple Access (TDMA) transmission make an ideal system for monitoring machine conditions in industrial plants because there is no need for electronic wiring. However, there has not yet been a successful field application of such a system, capable of continuously transmitting data at sample rates greater than 100 Hz. In this research, a TDMA network protocol capable of acquiring data from multiple sensors at sample rates greater than 100 Hz was developed for field application. The protocol was implemented in a single cluster-star topology network, and the system was evaluated based on the node number and transmission distance. Network simulator 2 (ns-2) was used for a real field simulation. Non-TDMA and TDMA protocol cases were compared using four sensor nodes. In the cases of 20-s and 40-s transmission times, there was little difference between the reception rates of the non-TDMA and TDMA systems. However, the difference was much greater when using a 60-s transmission time.

An Energy Balanced Multi-Hop Routing Mechanism considering Link Error Rate in Wireless Sensor Networks (무선 센서 네트워크의 링크 에러율을 고려한 에너지소모가 균등한 멀티 홉 라우팅 기법)

  • Lee, Hyun-Seok;Heo, Jeong-Seok
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.6
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    • pp.29-36
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    • 2013
  • In wireless sensor networks, energy is the most important consideration because the lifetime of the sensor node is limited by battery. Most of the existing energy efficient routing protocols use the minimum energy path to minimize energy consumption, which causes an unbalanced distribution of residual energy among nodes. As a result, the power of nodes on energy efficient paths is quickly depletes resulting in inactive. To solve these problems, a method to equalize the energy consumption of the nodes has been proposed, but do not consider the link error rate in the wireless environment. In this paper, we propose a uniform energy consumption of cluster-based multi-hop routing mechanism considering the residual energy and the link error rate. This mechanism reduces energy consumption caused by unnecessary retransmissions and distributes traffic evenly over the network because considering the link error rate. The simulation results compared to other mechanisms, the proposed mechanism is energy-efficient by reducing the number of retransmissions and activation time of all nodes involved in the network has been extended by using the energy balanced path.

The Robust Phylogeny of Korean Wild Boar (Sus scrofa coreanus) Using Partial D-Loop Sequence of mtDNA

  • Cho, In-Cheol;Han, Sang-Hyun;Fang, Meiying;Lee, Sung-Soo;Ko, Moon-Suck;Lee, Hang;Lim, Hyun-Tae;Yoo, Chae-Kyoung;Lee, Jun-Heon;Jeon, Jin-Tae
    • Molecules and Cells
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    • v.28 no.5
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    • pp.423-430
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    • 2009
  • In order to elucidate the precise phylogenetic relationships of Korean wild boar (Sus scrofa coreanus), a partial mtDNA D-loop region (1,274 bp, NC_000845 nucleotide positions 16576-1236) was sequenced among 56 Korean wild boars. In total, 25 haplotypes were identified and classified into four distinct subgroups (K1 to K4) based on Bayesian phylogenetic analysis using Markov chain Monte Carlo methods. An extended analysis, adding 139 wild boars sampled worldwide, confirmed that Korean wild boars clearly belong to the Asian wild boar cluster. Unexpectedly, the Myanmarese/Thai wild boar population was detected on the same branch as Korean wild boar subgroups K3 and K4. A parsimonious median-joining network analysis including all Asian wild boar haplotypes again revealed four maternal lineages of Korean wild boars, which corresponded to the four Korean wild boar subgroups identified previously. In an additional analysis, we supplemented the Asian wild boar network with 34 Korean and Chinese domestic pig haplotypes. We found only one haplotype, C31, that was shared by Chinese wild, Chinese domestic and Korean domestic pigs. In contrast to our expectation that Korean wild boars contributed to the gene pool of Korean native pigs, these data clearly suggest that Korean native pigs would be introduced from China after domestication from Chinese wild boars.

Time Synchronization Robust to Topology Change Through Reference Node Re-Election (기준노드의 재선정을 통한 토폴로지 변화에 강인한 시간 동기화)

  • Jeon, Young;Kim, Taehong;Kim, Taejoon;Lee, Jaeseang;Ham, Jae-Hyun
    • KIPS Transactions on Computer and Communication Systems
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    • v.8 no.8
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    • pp.191-200
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    • 2019
  • In an Ad-hoc network, a method of time synchronizing all the nodes in a network centering on one reference node can be used. A representative algorithm based on a reference node is Flooding Time Synchronization Protocol (FTSP). In the process of sending and receiving messages, predictable and unpredictable delays occur, which should be removed because it hinders accurate time synchronization. In multi-hop communications, hop delays occur when a packet traverses a number of hops. These hop delays significantly degrade the synchronization performance among nodes. Therefore, we need to find a method to reduce these hop delays and increase synchronization performance. In the FTSP scheme, hop delays can be greatly increased depending on the position of a reference node. In addition, in FTSP, a node with the smallest node ID is elected as a reference node, hence, the position of a reference node is actually arbitrarily determined. In this paper, we propose an optimal reference node election algorithm to reduce hop delays, and compare the performance of the proposed scheme with FTSP using the network simulator OPNET. In addition, we verify that the proposed scheme has an improved synchronization performance, which is robust to topology changes.