• Title/Summary/Keyword: cluster-head

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A Study of Key Pre-distribution Scheme in Hierarchical Sensor Networks (계층적 클러스터 센서 네트워크의 키 사전 분배 기법에 대한 연구)

  • Choi, Dong-Min;Shin, Jian;Chung, Il-Yong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.1
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    • pp.43-56
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    • 2012
  • Wireless sensor networks consist of numerous small-sized nodes equipped with limited computing power and storage as well as energy-limited disposable batteries. In this networks, nodes are deployed in a large given area and communicate with each other in short distances via wireless links. For energy efficient networks, dynamic clustering protocol is an effective technique to achieve prolonged network lifetime, scalability, and load balancing which are known as important requirements. this technique has a characteristic that sensing data which gathered by many nodes are aggregated by cluster head node. In the case of cluster head node is exposed by attacker, there is no guarantee of safe and stable network. Therefore, for secure communications in such a sensor network, it is important to be able to encrypt the messages transmitted by sensor nodes. Especially, cluster based sensor networks that are designed for energy efficient, strongly recommended suitable key management and authentication methods to guarantee optimal stability. To achieve secured network, we propose a key management scheme which is appropriate for hierarchical sensor networks. Proposed scheme is based on polynomial key pool pre-distribution scheme, and sustain a stable network through key authentication process.

Whole genome sequencing of Luxi Black Head sheep for screening selection signatures associated with important traits

  • Liu, Zhaohua;Tan, Xiuwen;Wang, Jianying;Jin, Qing;Meng, Xianfeng;Cai, Zhongfeng;Cui, Xukui;Wang, Ke
    • Animal Bioscience
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    • v.35 no.9
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    • pp.1340-1350
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    • 2022
  • Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH. Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (HP), fixation index (FST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (𝜃π) ratio. Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected. Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

Communication Protocol to Support Mobile Sinks by Multi-hop Clusters in Wireless Sensor Networks (무선 센서 네트워크에서 멀티-홉 클러스터를 통한 이동 싱크 지원 통신 프로토콜)

  • Oh, Seung-Min;Jung, Ju-Hyun;Lee, Jeong-Cheol;Park, Ho-Sung;Yim, Yong-Bin;Kim, Sang-Ha
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3A
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    • pp.287-295
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    • 2010
  • In wireless sensor networks(WSNs), the studies that support sink mobility without global position information exploit a Backbone-based Virtual Infrastructure (BVI) which considers one-hop clusters and a backbone-based tree. Since the clusters of a sink and a source node are connected via flooding into the infrastructure, it causes high routing cost. Although the network could reduce the number of clusters via multi-level clusters, if the source nodes exist at nearest clusters from the cluster attached by the sink and they are in different branches of the tree, the data should be delivered via detour paths on the tree. Therefore, to reduce the number of clusters, we propose a novel multi-hop cluster based communication protocol supporting sink mobility without global position information. We exploit a rendezvous cluster head for sink location service and data dissemination but the proposed protocol effectively reduces data detour via comparing cluster hops from the source. Simulation shows that the proposed protocol is superior to the existing protocols in terms of the data delivery hop counts.

Energy-Efficient Clustering Scheme using Candidates Nodes of Cluster Head (클러스터헤더 후보노드를 이용한 에너지 효율적인 클러스터링 방법)

  • Cho, Young-Bok;Kim, Kwang-Deuk;You, Mi-Kyeong;Lee, Sang-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.121-129
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    • 2011
  • One of the major challenges of minimum energy consumption for wireless sensor networks(WSN) environment. LEACH protocol is hierarchical routing protocol that obtains energy efficiency by using clustering. However, LEACH protocol in each round, because the new cluster configuration, cluster configuration, whenever the energy consumed shorten the life of the network. Therefore in this paper, the cluster is formed in WSN environment in early stage and the problems with energy waste have been solved by selecting C-node. In the initial round of proposed model uses 26 percent more than traditional LEACH energy consumption. However, as the round is ongoing, it has been proved by the network simulation tool that the waste of energy could be diminished up to 35%.

Advanced Stability Distributed Weighted Clustering Algorithm in the MANET (모바일 에드혹 네트워크에서 안정성을 향상시킨 분산 조합 가중치 클러스터링 알고리즘)

  • Hwang, Yoon-Cheol;Lee, Sang-Ho;Kim, Jin-Il
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.1 s.45
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    • pp.33-42
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    • 2007
  • Mobile ad-hoc network(MANET) can increase independence and flexibility of network because it consists of mobile node without the aid of fixed infrastructure. But, Because of unrestriction for the participation and breakaway of node, it has the difficulty in management and stability which is a basic function of network operation. Therefore, to solve those problems, we suggest a distributed weighted clustering algorithm from a manageable and stable point of view. The suggested algorithm uses distributed weighted clustering algorithm when it initially forms the cluster and uses a concept which is distributed gateway and sub-cluster head to reduce the re-clustering to the minimum which occurs mobile nodes after forming the cluster. For performance evaluation, We compare DCA and WCA with the suggested algorithm on the basis of initial overhead, resubscriber rate and a number of cluster.

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A Modified E-LEACH Routing Protocol for Improving the Lifetime of a Wireless Sensor Network

  • Abdurohman, Maman;Supriadi, Yadi;Fahmi, Fitra Zul
    • Journal of Information Processing Systems
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    • v.16 no.4
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    • pp.845-858
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    • 2020
  • This paper proposes a modified end-to-end secure low energy adaptive clustering hierarchy (ME-LEACH) algorithm for enhancing the lifetime of a wireless sensor network (WSN). Energy limitations are a major constraint in WSNs, hence every activity in a WSN must efficiently utilize energy. Several protocols have been introduced to modulate the way a WSN sends and receives information. The end-to-end secure low energy adaptive clustering hierarchy (E-LEACH) protocol is a hierarchical routing protocol algorithm proposed to solve high-energy dissipation problems. Other methods that explore the presence of the most powerful nodes on each cluster as cluster heads (CHs) are the sparsity-aware energy efficient clustering (SEEC) protocol and an energy efficient clustering-based routing protocol that uses an enhanced cluster formation technique accompanied by the fuzzy logic (EERRCUF) method. However, each CH in the E-LEACH method sends data directly to the base station causing high energy consumption. SEEC uses a lot of energy to identify the most powerful sensor nodes, while EERRCUF spends high amounts of energy to determine the super cluster head (SCH). In the proposed method, a CH will search for the nearest CH and use it as the next hop. The formation of CH chains serves as a path to the base station. Experiments were conducted to determine the performance of the ME-LEACH algorithm. The results show that ME-LEACH has a more stable and higher throughput than SEEC and EERRCUF and has a 35.2% better network lifetime than the E-LEACH algorithm.

A Routing Protocol for Assuring Scalability and Energy Efficiency of Wireless Sensor Network (WSN의 확장성과 에너지 효율성을 보장하는 라우팅 프로토콜)

  • Jeong, Yoon-Su;Kim, Yong-Tae;Park, Gil-Cheol;Lee, Sang-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.105-113
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    • 2008
  • While the wireless sensor network has a strong point which does not have effect on whole activities of network even though neighboring sensor nods fail activities of some sensor nod or make some functions disappear by the characteristic of similar information detection, it has problems which is slowing down of wireless medium, transfer character with severe error, limited power supply, the impossibility of change by optional arrangement of sensor nods etc. This paper proposes PRML techniques which performs the fittest course searching process to reduce power consumption of entire nods while guarantees the scalability of network organizing sensor nods hierarchically. The proposed technique can scatter the load of cluster head by considering the connectivity with surplus energy of nod and reduce the frequency of communication among the nods. As a result of the analysis in comparison with LEACH-C and HEED technique, PRML technique get efficiency of average 6.4% in energy consuming respect of cluster head, efficiency of average 8% in entire energy consuming respect, and more efficiency of average 7.5% in other energy consuming distribution of network scalability than LEACH-C and HEED technique.

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Mapping QTL for Grain Quality Traits Using an Introgression Line Population from a Cross between Ilpumbyeo and Moroberekan in Rice (일품벼/모로베레칸 이입계통을 이용한 미질특성 관련 QTL 분석)

  • Ju, Hong-Guang;Kim, Dong-Min;Oh, Chang-Sik;Kim, Myung-Ki;Kim, Kee-Jong;Ahn, Sang-Nag
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.429-436
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    • 2009
  • We conducted a QTL analysis of grain quality traits using 117 $BC_3F_4$ and $BC_3F_5$ lines developed from a cross between Ilpumbyeo and Moroberekan. Genotypes of 117 $BC_3F_5$ lines were determined using 134 simple sequence repeat (SSR) markers. A linkage map constructed using 134 SSR markers was employed to characterize quantitative trait loci (QTL). The 117 $BC_3F_4$ and $BC_3F_5$ lines were evaluated for eleven grain quality traits in 2005 and 2006. A total of 18 QTLs were identified for eleven traits, and the phenotypic variance explained by each QTL ranged from 9.9% to 35.2%. Moroberekan alleles contributed positive effects in the Ilpumbyeo background at two QTL loci for 1,000 grain weight. Four QTLs, two for chalky rice and one each for 1,000 grain weight and head rice were consistently detected in two consecutive years indicating that these QTLs are stable. Clusters of QTLs were observed in three chromosome regions. One cluster harboring five QTLs including head rice and brown rice ratio near SSR markers RM190 and RM314 was detected on chromosome 6. Another cluster harboring grain weight and white belly was detected on chromosome 2. Increase in white belly at this locus might be due to the increase in grain weight due to the presence of the Moroberekan allele. The Moroberekan alleles at two QTL loci, gw3 and gw4 associated with increased grain weight might be useful in breeding programs to develop high-yielding cultivars.

Clustering Triangular Routing Protocol in Wireless Sensor Network (무선 센서 네트워크에서 삼각 클러스터링 라우팅 기법)

  • Nurhayati, Nurhayati;Lee, Kyung Oh;Choi, Sung Hee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.11a
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    • pp.913-916
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    • 2010
  • Wireless sensor networks consist of small battery powered devices with limited energy resources. Once deployed, the small sensor nodes are usually inaccessible to the user, and thus replacement of the energy source is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the network. In BCDCP, all sensors send data from CH (Cluster Head) and then to BS (Base Station). BCDCP works well in small-scale network but in large scale network it is not appropriated since it uses much energy for long distance wireless communication. We propose a routing protocol - Triangular Clustering Routing Protocol (TCRP) - to prolong network life time through the balanced energy consumption. TCRP selects cluster head of triangular shape. The sensor field is divided into energy level and in every level we choose one node as a gate node. This gate node collects data and sends it to the leader node. Finally the leader node sends the aggregated data to the BS. We show TCRP outperforms BCDCP with several experiments.

Comparative Study on Somatotype Characteristic based on Sasang Physical Constitution and Body Measurement Method for Women in their 20's (사상체질(四象體質)에 근거(根據)한 체질별(體質別) 체형특성(體型特性)과 인체계측(人體計測)을 통(通)한 유형별(類型別) 체형특성(體型特性)과의 비교연구(比較硏究)- 20대(代) 성인여성(成人女性)을 중심(中心)으로 -)

  • Shim, Boo-Ja;Suh, Chu-Yeon;Lee, So-Young
    • Journal of Fashion Business
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    • v.8 no.2
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    • pp.26-41
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    • 2004
  • This study aims to compare and analyze somatotype characteristics in clothing ergonomics as well as Sasang (Oriental physical constitution type classification into 4 kinds: taeyang, taeeum, soyang, soeum) medicine. The subjects were women collegians in their 20s. As a result, a new approach was made in somatotype classification. The following are conclusions: 1. The results of body measurement of the subjects belonged to 1 in most items when they were compared with the average records of female adults in their 20s in the national standard physique report. Thus, the subjects belonged to the average somatotype. 2. According to Sasang physical constitution classification, no subjects belonged to taeyang-type. Taeeum type (28.4%), had lower-body development greatest height and even development in width, thickness and girth. Soeum-type(37.8%) had the smallest physique. Soyang-type(33.8%) showed small values in height but great values in width, thickness and girth. 3. The factor analysis revealed 5 factors of somatotype characteristics: lower body factors including body weight, upper body factors, height factors including stature, belly width factors including waist and belly, and other factors comprising ankle and head size. 4. A cluster analysis by way of factor scores resulted in 3 types: cluster 1 44.6%, biggest values, largest somatotypes; cluster 2 17.6%, average somatotypes; cluster 3 tiniest somatotypes in most items. 5. In the crosstabs analysis, taeeum-type (57.6%) appeared a lot in cluster 1, soyang-type (76.9%) appeared most in cluster 2, and soeum-type (69.9%) was mostly seen in cluster 3. To sum up, the somatotype analysis of clothing ergonomics had something to do with constitution classification suggested in Sasang medicine. For clear justification, more systematic and scientific research should be followed with even more diverse subjects in sex and age.