• Title/Summary/Keyword: Redundant Resources

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An Overview of Content Poisoning in NDN: Attacks, Countermeasures, and Direction

  • Im, Hyeonseung;Kim, Dohyung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.7
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    • pp.2904-2918
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    • 2020
  • With a huge demand for replicated content on the Internet, a new networking paradigm called information-centric networking (ICN) has been introduced for efficient content dissemination. In ICN, named content is distributed over the network cache and it is accessed by name instead of a location identifier. These aspects allow users to retrieve content from any of the nodes having replicas, and consequently 1) network resources are more efficiently utilized by avoiding redundant transmission and 2) more scalable services are provided by distributing server loads. However, in-network caching in ICN brings about a new type of security issues, called content poisoning attacks, where fabricated content is located in the network cache and interferes with the normal behavior of the system. In this paper, we look into the problems of content poisoning in ICN and discuss security architectures against them. In particular, we reconsider the state-of-the-art schemes from the perspective of feasibility, and propose a practical security architecture.

An Algorithm to Reduce the Number of Nodes in Active Spectrum Sensing Via Cooperative Sequential Detection

  • Truc, Tran Thanh;Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.12 no.2
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    • pp.148-154
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    • 2012
  • In this paper, we propose an algorithm to conserve resources of the common control channel in a cognitive radio network by rejecting the redundant users using cooperative spectrum sensing. The proposed scheme is investigated under the paradigm of active spectrum sensing and a sequential detection technique. The algorithm is based on the J-divergence between the hypotheses of non primary user operation and the otherwise case. We select the most significant eigenvalues, which primarily affect the global statistical test. For the case where interference is from a secondary system transmission, a match filter is first employed to remove the degradation, and then the proposed algorithm is employed to remove the cooperative sensing nodes. Numerical results are provided and compared with conventional cases in order to validate the performance of the proposed algorithm.

Studies on the Construction of Mutant Diversity Pool (MDP) lines, and their Genomic Characterization in Soybean

  • Dong-Gun Kim;Sang Hoon Kim;Chang-Hyu Bae;Soon-Jae Kwon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2021.04a
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    • pp.9-9
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    • 2021
  • Mutation breeding is useful for improving agronomic characteristics of various crops. In this study, we constructed soybean Mutant Diversity Pool (MDP) from 1,695 gamma-irradiated mutants through two selection phases over M1 to M12 generations; we selected 523 mutant lines exhibiting at least 30% superior agricultural characteristics, and, second, we eliminated redundant morphological phenotypes in the M12 generation. Finally, we constructed 208 MDP lines and investigated 11 agronomic traits. We then assessed the genetic diversity and inter-relationships of these MDP lines using target region amplification polymorphism (TRAP) markers. Among the different TRAP primer combinations, polymorphism levels and PIC values averaged 59.71% and 0.15, respectively. Dendrogram and population structure analyses divided the MDP lines into four major groups. According to an analysis of AMOVA, the percentage of inter-population variation among mutants was 11.320 (20.6%), whereas mutant inter-population variation ranged from 0.231 (0.4%) to 14.324 (26.1%). Overall, the genetic similarity of each cultivar and its mutants were higher than within other mutant populations. In an analysis of the genome-wide association study (GWAS) using based on the genotyping-by-sequencing (GBS), we detected 66 SNPs located on 13 different chromosomes were found to be highly associated with four agronomic traits: days of flowering (33 SNPs), flower color (16 SNPs), node number (6 SNPs), and seed coat color (11 SNPs). These results are consistent with those previously reported for other genetic resource populations, including natural accessions and recombinant inbred line. Our observations suggest that genomic changes in mutant individuals induced by gamma rays occurred at the same loci as those of natural soybean population. This study has demonstrated that the integration of GBS and GWAS can serve as a powerful complementary approach to gamma-ray mutation for the dissection of complex traits in soybean.

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Incompetent Construction Technologies and Resources in the Construction Industry of Yemen

  • Sultan, Basil;Alaghbari, Wa'el
    • Journal of Construction Engineering and Project Management
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    • v.4 no.1
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    • pp.8-14
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    • 2014
  • The Construction industry in Yemen confronts many development constraints, such as the inadequate implementation of appropriate building materials and labour construction technologies. Thus, this research looks over building materials and labour construction technologies used on the local housing construction projects by verifying the percentage of construction expenditure consumed by the main construction components (Materials, Labour and Overhead and Profit), along with the implemented construction technologies. The paper conducts a survey to acquire the cost distribution of the construction main components. The outcomes of the survey were discussed; the discussion was supported by literature on similar issues from some countries. The outcomes confirmed the relatively limited percentage in labour cost and profit, and the elevated percentage of construction materials cost, which are because of the excessive and inappropriate use of materials. What's more, established that the excessively redundant unskilled labours are not effectively engaged in the construction activities, this is due to the tendency of the market in using labour-base technologies. This paper is to recommend a suitable policies and strategies has to be used to decrease cost by using efficiently appropriate construction practice and local materials, moreover take advantage of excessive labour to reduce unemployment.

A Study on the Design of Network System for Defense Integrated Data Center Using NFV/SDN (NFV/SDN을 활용한 군(軍) 데이터센터 네트워크 체계 설계에 관한 연구)

  • Chae, Woong;Kwon, Taewook
    • KIPS Transactions on Computer and Communication Systems
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    • v.9 no.2
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    • pp.31-36
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    • 2020
  • The creation of the Defense Integrated Data Center(DIDC) has resulted in a reduction in manpower, operating costs, efficient and effective management of resources. However, it is difficult to effectively collect and manage the data of a large number of battlefields coming from equipments such as drones, robots, and IoT added to the fourth industrial revolution and the future battlefield. Therefore, we will propose the design of DIDC network system using NFV and SDN, which are emerging as the core technologies of 5G, a mobile communication technology. After analyzing the data sheet of each equipment, it is considered that by integrating the redundant functions, energy efficiency, resource utilization and effective network management will be possible.

Development of Integrated Start-up and Excitation System for Gas Turbine Synchronous Generator (가스터빈 동기기 통합형 기동 및 여자시스템 개발)

  • Ryu, Hoseon;Cha, Hanju
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.3
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    • pp.183-188
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    • 2014
  • Power conversion systems used in large gas turbine power plant can be divided into two main part. Because of the initial start-up characteristic of the gas turbine combustor, the gas turbine must be accelerated by starting device(LCI : Load Commutated Inverter) up to 10%~20% of rated speed to ignite it. In addition, the ECS(Excitation Control system) is used to control the rotor field current and reactive power in grid-connected synchronous generator. These two large power conversion systems are located in the same space(container) because of coordination control. Recently, many manufactures develop high speed controller based on function block available in the LCI and ECS with the newest power semiconductor. We also developed high speed controller based on function block to be using these two system and it meets the international standard IEC61131 as using real-time OS(VxWorks) and ISaGRAF. In order to install easily these systems at power plant, main controller, special module and IO module are used with high speed communication line other than electric wire line. Before initial product is installed on the site, prototype is produced and tests are conducted for it. The performance results of Integrated controller and application program(SFC, ECS) were described in this paper. The test results will be considered as the important resources for the application in future.

Individual differences in categorical perception: L1 English learners' L2 perception of Korean stops

  • Kong, Eun Jong
    • Phonetics and Speech Sciences
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    • v.11 no.4
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    • pp.63-70
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    • 2019
  • This study investigated individual variability of L2 learners' categorical judgments of L2 stops by exploring English learners' perceptual processing of two acoustic cues (voice onset time [VOT] and f0) and working memory capacity as sources of variation. As prior research has reported that English speakers' greater use of the redundant cue f0 was responsible for gradient processing of native stops, we examined whether the same processing characteristics would be observed in L2 learners' perception of Korean stops (/t/-/th/). 22 English learners of L2 Korean with a range of L2 proficiency participated in a visual analogue scaling task and demonstrated variable manners of judging the L2 Korean stops: Some were more gradient than others in performing the task. Correlation analysis revealed that L2 learners' categorical responses were modestly related to individuals' utilizations of a primary cue for the stop contrast (VOT for L1 English stops and f0 for L2 Korean stops), and were also related to better working memory capacity. Together, the current experimental evidence demonstrates adult L2 learners' top-down processing of stop consonants where linguistic and cognitive resources are devoted to a process of determining abstract phonemic identity.

Temporary Access Selection Technology in WIFI Networks

  • Lu, Yang;Tan, Xuezhi;Mo, Yun;Ma, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.12
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    • pp.4269-4292
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    • 2014
  • Currently, increasing numbers of access points (AP) are being deployed in enterprise offices, campuses and municipal downtowns for flexible Internet connectivity, but most of these access points are idle or redundant most of the time, which causes significant energy waste. Therefore, with respect to power conservation, applying energy efficient strategies in WIFI networks is strongly advocated. One feasible method is dynamically managing network resources, particularly APs, by powering devices on or off. However, when an AP is powered on, the device is initialized through a long boot time, during which period clients cannot be associated with it; therefore, the network performance would be greatly impacted. In this paper, based on a global view of an entire WLAN, we propose an AP selection technology, known as Temporary Access Selection (TAS). The criterion of TAS is a fusion metric consisting of two evaluation indexes which are based on throughput and battery life, respectively. TAS is both service and clients' preference specific through balancing the data rate, battery life and packet size. TAS also works well independently in traditional WLANs in which no energy efficient strategy is deployed. Moreover, this paper demonstrates the feasibility and performance of TAS through experiments and simulations with Network Simulator version 3 (NS3).

Analysis of Expressed Sequence Tags Generated from the Posterior Silkgland cDNA Clones of Antheraea yamamai (천잠 후부 견사선 유래 발현 유전자 꼬리표 작성 및 분석)

  • 윤은영;구태원;강석우;이혜원;황재삼;김호락
    • Journal of Life Science
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    • v.10 no.2
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    • pp.188-195
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    • 2000
  • In order to understand molecular events during silk synthesis and provide genetic resources for molecular breeding, we had analyzed the cDNA library constructed from the posterior silkgland of Antheraea yamamai and partially sequenced 276 randomly selected genes from the cDNA library. Database comparisons of the expressed sequence tags (ESTs) revealed that 26 non-redundant clones showed a high similarity with previously identified genes. Among them, 17 clones exhibited a homology with previously identified insect genes and 9 clones were identical to genes that were previously identified from other organisms. A functional categorization showed that silk synthesis-defense- or stress-related genes, as well as genes involved in the metabolic pathways and in the transcriptional or translational apparatus are represented. In this report, the clone (AY479) which had high similarity with fibroin from A. pernyi was particularly analyzed in detail. The AY479 clone was carboxyl terminal region of fibroin. The 472 bp cDNA has 123 amino acids that shared 85% homology with the fibroin from A. pernyi and its deduced peptide had unique feature, that is, sites of alanine rich residues.

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An Understanding of Keyword Networks on Research Trends on Jeju Tourism and Sports Tourism (제주관광과 스포츠관광에 관한 연구의 키워드 네트워크에 대한 이해)

  • Joonhyeong Joseph Kim;Sung-Hun Choi
    • Asia-Pacific Journal of Business
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    • v.15 no.1
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    • pp.305-318
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    • 2024
  • Purpose - The purpose of this study was to conduct a preliminary study to identify key trends on research articles indexed in KCI in relation to tourism in Jeju and sports tourism. Design/methodology/approach - Information regarding research articles focused on Jeju tourism and sports tourism indexed in KCI (145 and 120 articles respectively) were collected and finally abstract written in Korean of 100 and 91 articles on sports tourism and Jeju tourism respectively were chosen for the further analysis after removing redundant articles. R program was used to analyze keyword frequencies, co-occurring terms, and degree/betweeness centrality measures and visualize the keyword network results. Findings - Event, marketing, content, program, implication, service, stadium, and tourism destination have been identified as keywords with highest frequencies among research on sport tourism, whereas tourism destination, image, brand, content, data, Chinese, satisfaction, eco-tourism service, place of arrival were highly appearing terms among research on Jeju tourism. Research implications or Originality - This study highlighted that Jeju has been interlinked with a range of terms such as programs influencing Jeju tourism, natural environment, tourism-related resources (e.g., museums, dramas, etc.), whereas sports has been closely related to sports event and vaiours types of sports (e.g., bicycle, staking, and scuber), but not to Jeju-do.