• Title/Summary/Keyword: cluster-head

Search Result 428, Processing Time 0.03 seconds

Neighbor Node Discovery and Load Balancing Schemes for Energy-Efficient Clustering in Wireless Sensor Networks (주변 노드 발견을 통한 무선 센서 네트워크에서의 에너지 효율적인 클러스터링 및 전력 균형 분산 기법)

  • Choi, Ji-Young;Kang, Chung-Gu
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.11A
    • /
    • pp.1147-1158
    • /
    • 2006
  • Clustering algorithm is an essential element to implement a hierarchical routing protocol, especially for a large-scale wireless sensor network. In this paper, we propose a new type of energy-efficient clustering algorithm, which maximizes the physical distance between cluster head and gateway by a neighbor node discovery mechanism. Furthermore, a slave/master patching scheme is introduced as a useful means of further improving the energy-efficiency. It has been shown that the number of cluster heads can be reduced by as many as 21% as compared with the existing clustering algorithms.

Stock identification of minor carp, Cirrhinus reba, Hamilton 1822 through landmark-based morphometric and meristic variations

  • Ethin, Rokhsana;Hossain, Md Shakhawate;Roy, Animesh;Rutegwa, Marcellin
    • Fisheries and Aquatic Sciences
    • /
    • v.22 no.6
    • /
    • pp.12.1-12.8
    • /
    • 2019
  • Background: Wild fish populations stock is continuously diminishing in the Indo-Ganges river basin, and the population status of most fishes is unidentified. The identification of the population status and the conservation of commercially important and endemic wild fish populations in this region are crucial for the management. The aim of this paper was to identify the population status of Cirrhinus reba, a promising aquaculture but vulnerable species in the Indo-Ganges river basin in Bangladesh. Methods: C. reba samples were collected from four isolated populations of the Brahmaputra (n = 30), the Padma (33), the Karatoya (31), and the Jamuna Rivers (30) in Bangladesh, and the population status was evaluated using morphometric and landmark comparisons. Data were analyzed with the Kruskal-Wallis test, univariate analysis, discriminant function analysis, and the formation of a dendrogram. Results: Three meristic characters (Pectoral fin rays, caudal fin rays, scale in lateral lines), four morphometric characters (head length, pre-orbital length, post-orbital length, maximum body depth), and truss measurement (4-7) were significantly different among the stocks. The step-wise discriminant function analysis retained 15 variables from morphometric and landmark measurements that significantly differentiated the populations based on the constructed DFI and DFII. Discriminate function analysis also showed that 91.2% of the original groups were classified into their correct samples. The cluster analysis of Euclidean distances placed the Jamuna population in one cluster and the Brahmaputra, the Padma, and the Karatoya populations in the second one. Conclusion : Morphological differences among the stock were probably due to different ancestral origin. This is the first report about population status of C. reba in their natural habitat of the Indian subcontinent. Further genetic studies and the evaluation of environmental impact on C. reba populations in Bangladesh are suggested to support our findings.

Patterns of morphological variation in the Schlegel's Japanese gecko (Gekko japonicus) across populations in China, Japan, and Korea

  • Kim, Dae-In;Park, Il-Kook;Ota, Hidetoshi;Fong, Jonathan J.;Kim, Jong-Sun;Zhang, Yong-Pu;Li, Shu-Ran;Choi, Woo-Jin;Park, Daesik
    • Journal of Ecology and Environment
    • /
    • v.43 no.4
    • /
    • pp.332-340
    • /
    • 2019
  • Background: Studies of morphological variation within and among populations provide an opportunity to understand local adaptation and potential patterns of gene flow. To study the evolutionary divergence patterns of Schlegel's Japanese gecko (Gekko japonicus) across its distribution, we analyzed data for 15 morphological characters of 324 individuals across 11 populations (2 in China, 4 in Japan, and 5 in Korea). Results: Among-population morphological variation was smaller than within-population variation, which was primarily explained by variation in axilla-groin length, number of infralabials, number of scansors on toe IV, and head-related variables such as head height and width. The population discrimination power was 32.4% and in cluster analysis, populations from the three countries tended to intermix in two major groups. Conclusion: Our results indicate that morphological differentiation among the studied populations is scarce, suggesting short history for some populations after their establishment, frequent migration of individuals among the populations, and/or local morphological differentiation in similar urban habitats. Nevertheless, we detected interesting phenetic patterns that may predict consistent linkage of particular populations that are independent of national borders. Additional sampling across the range and inclusion of genetic data could give further clue for the historical relationship among Chinese, Japanese, and Korean populations of G. japonicus.

Effects of directional transmission on clustering WSN (클러스터링 센서네트워크의 방향성 전송 효과)

  • Kim, Jeong-Mi;Zhang, Zhe-Hao;Kim, Chong-Gun
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.37 no.4B
    • /
    • pp.258-268
    • /
    • 2012
  • Wireless Sensor Network(WSN) is constituted by low-cost and low-energy, So the most important issue is that the task of the sensor performs successfully by using less energy. In previous WSN, determination of the header and gathering sensor data solution by header give great affection to the performance of network. In this paper, we propose a Hybrid transmission method which considers the direction of data collections. In the proposed hybrid routing method, all of the sensors determine that transmission the data to the sink node directly or indirectly using the head node depend on the location of the head node in the cluster. The performance is compared with the LEACH(Low Energy Adaptive Clustering Hierarchy) by experimental analysis. The results show that the preposed method can reduce the communication distance and energy consumption by avoiding the detour direction of transmission of the data.

Association Study Analysis of Cluster-of-Differentiation Antigen 9 (CD9) Gene Polymorphism (g.358A>T) for Duroc Boar Post-thawed Semen Motility and Kinematic Characteristics

  • Cho, Eun-Seok;Sa, Soo-Jin;Kim, Ki-Hyun;Lee, Mi-Jin;Ko, Jun-Ho;Kim, Young-Ju;Seol, Kuk-Hwan;Hong, Joon-ki;Kim, Kwang-Sik;Kim, Yong-Min;Woo, Jae-Seok
    • Journal of Embryo Transfer
    • /
    • v.30 no.2
    • /
    • pp.109-114
    • /
    • 2015
  • Cryopreservation of boar semen is continually researched in reproductive technologies and genetic resource banking in breed conservation. For evaluating the boar semen quality, sperm motility (MOT) is an important parameter because the movement of spermatozoa indicates active metabolism, membrane integrity and fertilizing capacity. Various researches have been trying to improve the quality of semen post-thawed in boar. Recently, polymorphism (g.358A>T) of cluster-of-differentiation antigen 9 (CD9) gene reported to be significant association with MOT. Also, CD9 gene was expressed in the male germ line stem cells is crucial for sperm-egg fusion, and was therefore selected as candidate gene for boar semen. This study was conducted to evaluate the pig SNP (g.358A>T) of CD9 gene as a positional controlling for semen parameters of post-thawed boar semen. To results, the g.358A>T SNP of the CD9 gene was significantly associated with the traits such as MOT, curve linear velocity, straight line velocity, average path velocity and amplitude of lateral head displacement. Particularly, the g.358A>T SNP significantly has the highest association with MOT and animals with AA genotype (p<0.001). Therefore, we suggest that the g.358A>T in the intron 6 region of the porcine CD9 may be used as a molecular marker for Duroc boar Post-thawed semen quality, although its functional effect was not defined yet.

A Study on the Energy Efficient Data Aggregation Method for the Customized Application of Underwater Wireless Sensor Networks (특정 응용을 위한 수중센서네트워크에서 에너지 효율적인 데이터통합 방법 연구)

  • Kim, Sung-Un;Park, Seon-Yeong;Yu, Hyung-Cik
    • Journal of Korea Multimedia Society
    • /
    • v.14 no.11
    • /
    • pp.1438-1449
    • /
    • 2011
  • UWSNs(Underwater Wireless Sensor Networks) need effective modeling fitted to the customized type of application and its covering area. In particular it requires an energy efficient data aggregation method for such customized application. In this paper, we envisage the application oriented model for monitoring the pollution or intrusion detection over a given underwater area. The suggested model is based on the honeycomb array of hexagonal prisms. In this model, the purpose of data aggregation is that the head node of each layer(cluster) receives just one event data arrived firstly and transfer this and its position data to the base station effectively in the manner of energy efficiency and simplicity without duplication. Here if we apply the existent data aggregation methods to this kind of application, the result is far from energy efficiency due to the complexity of the data aggregation process based on the shortest path or multicast tree. In this paper we propose three energy efficient and simple data aggregation methods in the domain of cluster and three in the domain of inter-cluster respectively. Based on the comparative performance analysis of the possible combination pairs in the two domains, we derive the best energy efficient data aggregation method for the suggested application.

Location Determination and Measured Data Analysis of a Shipboard Indoor Signal Propagation Characteristics Based on Signature Sequence (서명 수열기반 선내 전파 전달특성 측정 위치선정 방안 및 측정 데이터 분석)

  • Kim, Jeong-Ho;Lee, Seong-Ro
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.1
    • /
    • pp.198-201
    • /
    • 2015
  • The prompt and accurate location determination of the nodes of the wireless indoor shipboard networks is crucial to forming the stable wireless shipboard sensor networks. To this end in this paper it can be achieved through the measurement of the bi-directional channel qualities among the nodes after the locations of the sensor nodes temporarily placed. For the 1st stage the piconet-type sensor networks are considered to measure the channel qualities between a specific node and the cluster node which is the master node. After finishing the 1st stage measurement the nodes needing the relay nodes are selected and the measurement action goes into the 2nd stage. In the 2nd stage the measurement between a candidate relay node and the node needing a relay node starts to begin. After the 2nd stage the relay nodes to connect to the cluster node are fixed and the information delivery paths between a node and the cluster head are established. In this paper the measurement results in the realistic environment are gathered and analysed to show that the measurement procedure can be applied in the wireless indoor shipboard networks.

A Study on monitoring of the moving object with considering power saving in Wireless Sensor Networks (무선 센서 네트워크에서 저전력을 고려한 이동체의 모니터링에 관한 연구)

  • Lee, Jong-Chool;Youn, Hee-Yong
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2005.11a
    • /
    • pp.175-177
    • /
    • 2005
  • 무선 센서 네트워크에서는 배터리에 의존하는 수많은 센서 노드들로 구성이 된다. 이때, 물체들을 감지하기 위해서는 센서들은 켜져 있어야 하고, 수집한 데이터는 클러스터 헤드(Cluster Head)나 싱크(sink) 로 보내주어야 한다. 일련의 동작을 위해서 센서들은 않은 에너지를 소모하게 된다 이를 보완하기 위해서 LEACH 라는 방법을 이용하여, 클러스터 헤드 만이 싱크로 데이터를 전송하고, 에너지를 균일하게 소모하기 위한 기법을 사용한다. 본 논문에서는 기본적으로 LEACH 방법을 이용하면서, 이동체의 이동을 감지함에 있어서, 이동체의 예상 이동영역을 예측하여, 예상 이동영역내에 존재하지 않는 센서 노드들은 다음 라운드가 시작할 때까지 Sleep 하도록 하고. 예상 이동영역내에 있는 센서 노드들만 감지하도록 하여, 에너지의 소모를 줄였다. 이때 예상 이동영역은 싱크가 이전에 수집한 데이터로 계산하여, 이동체들의 정보를 모든 노드들에게 브로드 캐스트(Broadcast)하고, 매 라운드마다 클러스터 헤드선택까지는 LEACH 와 마찬가지로 모든 센서 노드들이 참여하지만, 이후 클러스터의 구성원이 되기 위해서는 예상 이동영역내에 존재해야 한다. 만약 해당 라운드에서클러스터 헤드가 되어도, 구성원이 존재하지 않는 다면 다시 Sleep 하도록 하여, 에너지 소모를 줄였다.

  • PDF

A Biometric-based User Authentication and Key Agreement Scheme for Heterogeneous Wireless Sensor Networks

  • Chen, Ying;Ge, Yangming;Wang, Wenyuan;Yang, Fengyu
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.4
    • /
    • pp.1779-1798
    • /
    • 2018
  • Heterogeneous wireless sensor networks (HEWSN) is a kind of wireless sensor networks (WSN), each sensor may has different attributes, HEWSN has been widely used in many aspects. Due to sensors are deployed in unattended environments and its resource constrained feature, the design of security and efficiency balanced authentication scheme for HEWSN becomes a vital challenge. In this paper, we propose a secure and lightweight user authentication and key agreement scheme based on biometric for HEWSN. Firstly, fuzzy extractor is adopted to handle the user's biometric information. Secondly, we achieve mutual authentication and key agreement among three entities, which are user, gateway and cluster head in the four phases. Finally, formal security analysis shows that the proposed scheme defends against various security pitfalls. Additionally, comparison results with other surviving relevant schemes show that our scheme is more efficient in term of computational cost, communication cost and estimated time. Therefore, the proposed scheme is well suitable for practical application in HEWSN.

Design Variable Selection and Screening for the Perceived Quality Analysis of Front Visibility in Motor Vehicle Design (운전 자세에서 인지되는 시야 개방감에 대한 영향 변수 추론 및 모형화 방법)

  • Oh, Jin-Wook;Yun, Myung-Hwan
    • IE interfaces
    • /
    • v.21 no.1
    • /
    • pp.43-50
    • /
    • 2008
  • Understanding consumers' latent desires for product form has now become a critical issue in product design. Accordingly, product development processes is rapidly changing from product-oriented development to user-centered development. Driver visibility is considered as an important element of driving posture packaging in automobile interior design. This study presents a systematic process for driver visibility analysis approached from affective engineering method that provides design variable selection and screening with respect to the image/impression element of the human visibility. Also, the analysis of front visibility, often called the feeling of "openness", in motor vehicle interior design, is selected and practiced a case study using the systematic process proposed in this study. Twenty six participants evaluated the feeling of openness for thirty motor vehicles following the perceived scale of affective design factors. The results showed that variables such as the height of head lining, the height of cluster housing, the gradient of windshield and the volume of A-pillar were the critical design variables which affect the feeling of openness in a motor vehicle.