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A Multi-Chain Based Hierarchical Topology Control Algorithm for Wireless Sensor Networks

  • Tang, Hong;Wang, Hui-Zhu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3468-3495
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    • 2015
  • In this paper, we present a multi-chain based hierarchical topology control algorithm (MCHTC) for wireless sensor networks. In this algorithm, the topology control process using static clustering is divided into sensing layer that is composed by sensor nodes and multi-hop data forwarding layer that is composed by leader nodes. The communication cost and residual energy of nodes are considered to organize nodes into a chain in each cluster, and leader nodes form a tree topology. Leader nodes are elected based on the residual energy and distance between themselves and the base station. Analysis and simulation results show that MCHTC outperforms LEACH, PEGASIS and IEEPB in terms of network lifetime, energy consumption and network energy balance.

Action Recognition with deep network features and dimension reduction

  • Li, Lijun;Dai, Shuling
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.2
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    • pp.832-854
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    • 2019
  • Action recognition has been studied in computer vision field for years. We present an effective approach to recognize actions using a dimension reduction method, which is applied as a crucial step to reduce the dimensionality of feature descriptors after extracting features. We propose to use sparse matrix and randomized kd-tree to modify it and then propose modified Local Fisher Discriminant Analysis (mLFDA) method which greatly reduces the required memory and accelerate the standard Local Fisher Discriminant Analysis. For feature encoding, we propose a useful encoding method called mix encoding which combines Fisher vector encoding and locality-constrained linear coding to get the final video representations. In order to add more meaningful features to the process of action recognition, the convolutional neural network is utilized and combined with mix encoding to produce the deep network feature. Experimental results show that our algorithm is a competitive method on KTH dataset, HMDB51 dataset and UCF101 dataset when combining all these methods.

The Design and Verification of Multicast Key Distribution Protocol for Group Communication (그룹 통신을 위한 멀티캐스트 키 분배 프로토콜 설계 및 검증)

  • 김봉한
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.10 no.2
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    • pp.31-42
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    • 2000
  • 특성 사용자 그룹에게만 음성과 영상 데이터를 전송할 수 있는 통신 메커니즘을 가진 멀티캐스트는 유니캐스트와 비교해서 통신 링크의 수가 상당히 많으므로 부당한 공격자로부터 신분위장 서비스 부인 공격과 재전송 공격 부인, 트래픽 관찰 공격을 받기가 쉽다. 그러므로 본논문에서는 현재 멀티캐스트 통신을 위해서 제안 및 사용되고 있는 여러 가지 멀티캐스트 라우팅 프로토콜 중에서 보다 효율적인 보안 체계를 구성할 수 있는 공유 트리를 기반으로 하는 코어 기반 트리(CBT: Core Based Tree)를 이용하여 3개로 구성된 그룹키 KEK TEK을 획득함으로서 안전한 멀티캐스트 통신이 가능한 키 분배 프로토콜을 설계하였다 그리고 패트리넷을 이용하여 안전성을 검증하였다.

Cyclic Seismic Testing of Full-Scale Column-Tree Type Steel Moment Connections (반복재하 실물대 실험에 의한 컬럼-트리(Column-Tree) 형식 철골 모멘트 접합부의 내진거동 연구)

  • Lee, Cheol Ho;Park, Jong Won
    • Journal of Korean Society of Steel Construction
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    • v.10 no.4 s.37
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    • pp.629-639
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    • 1998
  • This paper summarizes the results of full-scale cyclic seismic performance tests on three column-tree type steel moment connections. Each test specimen consisted of a $H-600{\times}200$ beam and a $H-400{\times}400$ column of SS41 (SS400). Key parameter included was column PZ (panel zone) strength relative to beam strength. The seismic performance of specimen with stronger PZ tended to be inferior. Total plastic rotations available in the specimens ranged from 1.8 to 3.0 (% rad). The limited test results in this study seem to support the speculation that permitting PZ yielding shall be more beneficial to enhancing total plastic rotation capacity of the moment connection. Beam flange fracture across the heat affected zone and divot-type pullout of the column flange were observed in the tests. A conceptual mechanical model consistent with observed test results was also sought.

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Chemopreventive Effects of Elm Tree Root Extract on Colonic Aberrant Crypt Foci Induced by 1,2-Dimethylhydrazine in F344 Rats

  • Kwon, Hyun-Jung;Kim, Tae-Myoung;Ryu, Jae-Myun;Son, Seung-Hwan;Hong, Jin-Tae;Jeong, Heon-Sang;Kang, Jin-Seok;Ahn, Ji-Yun;Kim, Sung-Ran;Ha, Tae-Youl;Kim, Dae-Joong
    • Preventive Nutrition and Food Science
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    • v.13 no.3
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    • pp.157-165
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    • 2008
  • Cancer-preventive effects of ethanol extract of elm tree root (EEE) were investigated. In the in vitro cytotoxicity assay, colon cancer cells were incubated with a chloroform fraction of EEE (CF-EEE). CF-EEE significantly inhibited the proliferation of cells and induced apoptotic cell death in a dose-dependent manner. For the assessment of chemopreventive efficacy in vivo, male F344 rats were fed with EEE (0.5 or 1%) in diet for 8 weeks, and were subcutaneously injected with 1,2-dimethylhydrazine (DMH) to induce colonic aberrant crypt foci (ACF). EEE (0.5 and 1%) significantly decreased both the numbers of AC (1191.1/colon) and ACF (529.3/colon) induced by DMH. In addition, in the Western blot analysis on the colonic mucosa, administration of EEE triggered expression of caspase-3, a key factor of an apoptotic cascade. These results suggest that extract of elm tree root may have potential chemopreventive principles that lead to apoptosis of cancer cells, and thereby suppress colorectal carcinogenesis during the initiation stage.

Chromosome-specific polymorphic SSR markers in tropical eucalypt species using low coverage whole genome sequences: systematic characterization and validation

  • Patturaj, Maheswari;Munusamy, Aiswarya;Kannan, Nithishkumar;Kandasamy, Ulaganathan;Ramasamy, Yasodha
    • Genomics & Informatics
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    • v.19 no.3
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    • pp.33.1-33.10
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    • 2021
  • Eucalyptus is one of the major plantation species with wide variety of industrial uses. Polymorphic and informative simple sequence repeats (SSRs) have broad range of applications in genetic analysis. In this study, two individuals of Eucalyptus tereticornis (ET217 and ET86), one individual each from E. camaldulensis (EC17) and E. grandis (EG9) were subjected to whole genome resequencing. Low coverage (10×) genome sequencing was used to find polymorphic SSRs between the individuals. Average number of SSR loci identified was 95,513 and the density of SSRs per Mb was from 157.39 in EG9 to 155.08 in EC17. Among all the SSRs detected, the most abundant repeat motifs were di-nucleotide (59.6%-62.5%), followed by tri- (23.7%-27.2%), tetra- (5.2%-5.6%), penta- (5.0%-5.3%), and hexa-nucleotide (2.7%-2.9%). The predominant SSR motif units were AG/CT and AAG/TTC. Computational genome analysis predicted the SSR length variations between the individuals and identified the gene functions of SSR containing sequences. Selected subset of polymorphic markers was validated in a full-sib family of eucalypts. Additionally, genome-wide characterization of single nucleotide polymorphisms, InDels and transcriptional regulators were carried out. These variations will find their utility in genome-wide association studies as well as understanding of molecular mechanisms involved in key economic traits. The genomic resources generated in this study would provide an impetus to integrate genomics in marker-trait associations and breeding of tropical eucalypts.

Design of 32-bit Floating Point Multiplier for FPGA (FPGA를 위한 32비트 부동소수점 곱셈기 설계)

  • Xuhao Zhang;Dae-Ik Kim
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.2
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    • pp.409-416
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    • 2024
  • With the expansion of floating-point operation requirements for fast high-speed data signal processing and logic operations, the speed of the floating-point operation unit is the key to affect system operation. This paper studies the performance characteristics of different floating-point multiplier schemes, completes partial product compression in the form of carry and sum, and then uses a carry look-ahead adder to obtain the result. Intel Quartus II CAD tool is used for describing Verilog HDL and evaluating performance results of the floating point multipliers. Floating point multipliers are analyzed and compared based on area, speed, and power consumption. The FMAX of modified Booth encoding with Wallace tree is 33.96 Mhz, which is 2.04 times faster than the booth encoding, 1.62 times faster than the modified booth encoding, 1.04 times faster than the booth encoding with wallace tree. Furthermore, compared to modified booth encoding, the area of modified booth encoding with wallace tree is reduced by 24.88%, and power consumption of that is reduced by 2.5%.

Molecular Characterization of a Transient Expression Gene Encoding for 1-Aminocyclopropane-1-carboxylate Synthase in Cotton (Gossypium hirsutum L.)

  • Wang, Xia;Zhang, Ying;Zhang, Jiedao;Cheng, Cheng;Guo, Xingqi
    • BMB Reports
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    • v.40 no.5
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    • pp.791-800
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    • 2007
  • Ethylene performs an important function in plant growth and development. 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS), the key enzyme involved in ethylene biosynthesis, has been the focus of most ethylene studies. Here, a cotton ACS gene referred to as Gossypium hirsutum ACS1 (GhACS1), was isolated. The full-length cDNA of GhACS1 encodes for a 476-amino acid protein which harbors seven conserved regions, 11 invariant amino acid residues, and the PLP binding active site, all of which characterize ACC synthases. Alignment analysis showed that GhACS1 shared a high degree of identity with other known ACC synthases from different species. Two introns were detected in the genomic DNA sequence, and the results of Southern blot analysis suggested that there might be a multi-gene family encoding for ACC synthase in cotton. From the phylogenetic tree constructed with 24 different kinds of ACC synthases, we determined that GhACS1 falls into group II, and was closely associated with the wound-inducible ACS of citrus. The analysis of the 5' flanking region of GhACS1 revealed a group of putative cis-acting elements. The results of expression analysis showed that GhACS1 displayed its transient expression nature after wounding, abscisic acid (ABA), and $CuCl_2$ treatments. These results indicate that GhACS1, which was transiently expressed in response to certain stimuli, may be involved in the production of ethylene for the transmission of stress signals.

Password-Based Authenticated Tripartite Key Exchange Protocol (패스워드 기반 인증된 3자 키 교환 프로토콜)

  • Lee, Sang-Gon;Lee, Hoon-Jae;Park, Jong-Wook;Yoon, Jang-Hong
    • Journal of Korea Multimedia Society
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    • v.8 no.4
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    • pp.525-535
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    • 2005
  • A password-based authenticated tripartite key exchange protocol based on A. Joux's protocol was proposed. By using encryption scheme with shared password, we can resolve man-in-the-middle attack and lack of authentication problems. We also suggested a scheme to avoid the offline dictionary attack to which symmetric encryption schemes are vulnerable. The proposed protocol does not require a trusted party which is required in certificate or identity based authentication schemes. Therefore in a ad hoc network which is difficult to install network infrastructure, the proposed protocol would be very useful. The proposed protocol is more efficient in computation aspect than any existing password-based authenticated tripartite key exchange protocols. When it is used as a base line protocol of tree based group key exchange protocol, the computational weak points of the proposed protocol are compensated.

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A GDPR based Approach to Enhancing Blockchain Privacy (GDPR에 기반한 블록체인 프라이버시 강화 방안)

  • Han, Sejin;Kim, Suntae;Park, Sooyoung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.5
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    • pp.33-38
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    • 2019
  • In this paper, we propose a new blockchain technology that could comply with GDPR. The proposed model can prevent illegal access by controlling access to the personal information according to a access policy. For example, it can control access to the information on a role-basis and information validation period. The core mechanism of the proposed model is to encrypt the personal information with public key which is associated with users attributes policy, and then decrypt it with a private key and users attributes based on a Attribute-based Encryption scheme. It can reduce a trusted third-part risk by replacing it with a number of nodes selected from the blockchain. And also the private key is generated in the form of one-time token to improve key management efficiency. We proved the feasibility by simulating the proposed model using the chaincode of the Hyperledger Fabric and evaluate the security.