• Journal of Advanced Navigation Technology
• /
• v.14 no.4
• /
• pp.495-503
• /
• 2010

The clustering is an important mechanism thai provides information for mobile nodes efficiently and improves the processing capacity for routing and the allocation of bandwidth. This paper proposes a clustering scheme based on the fuzzy relevance degree to solve problems such as node distribution found in the dynamic property due to mobility and flat structure and to enhance the routing performance. The proposed scheme uses the fuzzy relevance degree, ${\alpha}$, to select the cluster head for clustering in FSV (Fuzzy State Viewing) structure. The fuzzy relevance ${\alpha}$ plays the role in CH selection that processes the clustering in FSV. The proposed clustering scheme is used to solve problems found in existing 1-hop and 2-hop clustering schemes. NS-2 simulator is used to verify the performance of the proposed scheme by simulation. In the simulation the proposed scheme is compared with schemes such as Lowest-ID, MOBIC, and SCA. The simulation result showed that the proposed scheme has better performance than the other existing compared schemes.

• Journal of KIISE:Information Networking
• /
• v.33 no.4
• /
• pp.310-323
• /
• 2006

In this paper, we describe a secure cluster-routing protocol based on a multi-layer scheme in ad hoc networks. We propose efficient protocols, Authentication based on Multi-layer Clustering for Ad hoc Networks (AMCAN), for detailed security threats against ad hoc routing protocols using the selection of the cluster head (CH) and control cluster head (CCH) using a modification of cluster-based routing ARCH and DMAC. This protocol provides scalability of Shadow Key using threshold authentication scheme in ad hoc networks. The proposed protocol comprises an end-to-end authentication protocol that relies on mutual trust between nodes in other clusters. This scheme takes advantage of Shadow Key using threshold authentication key configuration in large ad hoc networks. In experiments, we show security threats against multilayer routing scheme, thereby successfully including, establishment of secure channels, the detection of reply attacks, mutual end-to-end authentication, prevention of node identity fabrication, and the secure distribution of provisional session keys using threshold key configuration.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.7
• /
• pp.3494-3510
• /
• 2019

Wireless sensor networks encounter energy saving as a major issue as the sensor nodes having no rechargeable batteries and also the resources are limited. Clustering of sensors play a pivotal role in energy saving of the deployed sensor nodes. However, in the cluster based wireless sensor network, the cluster heads tend to consume more energy for additional functions such as reception of data, aggregation and transmission of the received data to the base station. So, careful selection of cluster head and formation of cluster plays vital role in energy conservation and enhancement of lifetime of the wireless sensor networks. This study proposes a new mutation chemical reaction optimization (MCRO) which is an algorithm based energy efficient clustering protocol termed as MCRO-ECP, for wireless sensor networks. The proposed protocol is extensively developed with effective methods such as potential energy function and molecular structure encoding for cluster head selection and cluster formation. While developing potential functions for energy conservation, the following parameters are taken into account: neighbor node distance, base station distance, ratio of energy, intra-cluster distance, and CH node degree to make the MCRO-ECP protocol to be potential energy conserver. The proposed protocol is studied extensively and tested elaborately on NS2.35 Simulator under various senarios like varying the number of sensor nodes and CHs. A comparative study between the simulation results derived from the proposed MCRO-ECP protocol and the results of the already existing protocol, shows that MCRO-ECP protocol produces significantly better results in energy conservation, increase network life time, packets received by the BS and the convergence rate.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.4 no.4
• /
• pp.41-49
• /
• 2008

Sensor networks are often deployed in unattended environments, thus leaving these networks vulnerable to false data injection attacks in which an adversary injects forged reports into the network through compromised nodes. Such attacks by compromised sensors can cause not only false alarms but also the depletion of the finite amount of energy in a battery powered network. In order to reduce damage from these attacks, several security solutions have been proposed. Researchers have also proposed some techniques to increase the energy-efficiency of such security solutions. In this paper, we propose a CH(Cluster Header) selection algorithm to choose low power delivery method in sensor networks. The CNP(Contract Net Protocol), which is an approach to solve distribution problems, is applied to choose CHs for event sensing. As a result of employing CNP, the proposed method can prevent dropping of sensing reports with an insufficient number of message authentication codes during the forwarding process, and is efficient in terms of energy saving.

• Journal of the Ergonomics Society of Korea
• /
• v.17 no.3
• /
• pp.61-70
• /
• 1998

The purpose of this paper is to evaluate the input methods of the numeric keypads that are widely used in various types of consumer and industrial electronic products. Three methods to enter numerals using keypads were compared: (1) Machine Intelligence, (2) + 100 key, and (3) Enter key input methods. Experiments were conducted to compare these three input methods for the channel selection of TV. Experimental prototypes which simulate TV user interfaces were developed using $RAPID^{TM}$ for usability testings. In the experiment, data on subject performance such as completion time, operational errors, and user interaction were collected through auto-logging method and video recording. After each test session, subjective preference was also asked using a questionnaire. In order to analyze the type of operation errors and the error causation, operation sequences were analyzed from the collected data. The Enter key input method showed better performance than other input methods. Based on these results. we can conclude that the input method using numeric keypads should be compatible with generic number counting(to input ch 7, it would be better to input 7 directly than to input 07 or 007) and should switch the channel as quickly as possible. This conclusion can be applied to the design of user interfaces which require numeral inputs.

• Transactions of the Korean hydrogen and new energy society
• /
• v.27 no.4
• /
• pp.404-411
• /
• 2016

To select appropriate oxygen carrier candidates for chemical looping combustion, reduction characteristics of seven oxygen carriers were measured and discussed using three different reduction gases, such as $H_2$, CO, and $CH_4$. Moreover, attrition losses of those oxygen carriers also measured and compared. Among seven oxygen carrier particles, OCN703-1100 and NiO/bentonite particles showed higher oxygen transfer capacity than other particles, but these particles showed more attrition loss than other particles. C14 and C28 particles which used as cheap oxygen carriers in European country showed lower oxygen transfer capacity and less attrition loss. Based on the experimental results, we could select OCN717-R1SU, NC001, and N002 particles as candidates for future works because these oxygen carriers showed enough oxygen transfer capacity and good attrition resistance.

• Proceedings of the Korea Contents Association Conference
• /
• 2014.11a
• /
• pp.57-58
• /
• 2014

인플루엔자 A 바이러스의 아형인 H5N1은 고병원성으로 조류 독감을 일으킨다. H5N1 바이러스는 원래 조류끼리만 감염되는 독감이고, 사람에게는 전염되지 않는다고 알려져 있었으나, 2003년에 베트남과 중국을 시작으로 현재까지 168명의 사망자가 기록되고 있다. 그러나 현재 시판되고 있는 진단키트(Rapid diagnostic kits)들은 H5N1 에 특이적인 것이 아니라 influenza A virus 모두를 진단한다. 따라서 influenza 감염여부는 확인 할 수 있지만, 이것이 H5N1 인지는 확인 할 수가 없다. H5N1은 전염성이 강하기 때문에 빠르게 진단하여 감염조류를 살 처분 하여야 더 많은 경제적 손실을 줄일 수 있다. 따라서 H5N1 에만 특이적인 epitope를 네트워크 기반으로 예측하여 진단제에 응용할 수 있도록 하고자 한다. 각 서열 정보는 Openflu (http://openflu. vital-it.ch/browse.php)에서 얻었다. H5N1은 H1N1에서 유래되었기 때문에 두 subtype의 차이점을 알아보고자 TCOFFEE에서 multiple sequence alignment를 수행한 결과 N-terminal 부분이 상이하였다. 상이한 H5N1의 N-terminal 부분이 H5N1 virus에 감염된 모든 host에서 존재하는지 알아보기 위해 host가 사람인 경우와 조류인 경우를 TCOFFEE에서 alignment 하였다. 그 결과 H5N1의 N-terminal 부분은 사람과 조류에서 보존적이었다. 따라서 H5N1의 N-terminal이 다른 subtype과 유사하지 않고 H5에만 특이적이기 때문에 진단키트 제작을 위한 epitope로 사용할 수 있을 것으로 기대된다.

• Journal of Korean Home Economics Education Association
• /
• v.6 no.1
• /
• pp.43-60
• /
• 1994

The purpose of this study is to systematize the objectives and contents related to clothing education curriculum, and to research the needs for clothing education curriculum required y the Home Economics teachers working from elementary school to high school. These needs have been shown in the research by questionaires, which were distributed to the teachers in the Department of Home Economics School in Teajon and Ch‘ungch’ ongnam-do. The main results of obtained this study are as follows: First as the objectives of clothing education curriculum which are different from each school and each grade have not completely been systematizied they must be carefully reexamined and reorganizied in a coherent system. Second in the findings on the teacher's needs of clothing education curriculum the Home Economics teachers in elementary schools have basic knowledges and skills on clothing education. The teachers in middle schools have the knowledge of the selection care repair of cloths and also acquire skills for clothing education and consumption are some what difficult for elementary students to understand and the contents have been overlapped with those of middle schools curriculum they are not organized in a coherent system of clothing education curriculum higher than over and to systematize clothing education in a coherent and a unified way we must continue to study them and the needs for clothing education.

• Journal of the Korean Society for information Management
• /
• v.10 no.2
• /
• pp.111.1-111.1
• /
• 1993

There are two types of bibliographic database, the one IS bibliographic database with creativlty. theother is bibliographic database without creativlty, The purpose of this paper is to investigate the problemsof bibliographic database with creatlvity by giving consideration of copyright law and the problems ofbihographic database w~thout creat~vity by sui genem system. Thus thls paper provided the methods thatresolve the problems of the current copyright law in order to protect all types of database being producedby way of the cooperation between the libraries and the information service centers. Secondly, this paperprovlded the legal devlces to protect bibliographic database produced by the libraries wh~ch cannot beprotected due to the lack of the creatlvity in the selection or arrangement of the material.

• Journal of the Korean Society for information Management
• /
• v.10 no.2
• /
• pp.111-143
• /
• 1993

There are two types of bibliographic database, the one IS bibliographic database with creativlty. the other is bibliographic database without creativlty, The purpose of this paper is to investigate the problems of bibliographic database with creatlvity by giving consideration of copyright law and the problems of bihographic database w~thout creat~vity by sui genem system. Thus thls paper provided the methods that resolve the problems of the current copyright law in order to protect all types of database being produced by way of the cooperation between the libraries and the information service centers. Secondly, this paper provlded the legal devlces to protect bibliographic database produced by the libraries wh~ch cannot be protected due to the lack of the creatlvity in the selection or arrangement of the material.