• Journal of Industrial Technology
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• v.28 no.B
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• pp.245-250
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• 2008

Recently, mobile devices have supported wireless LAN as well as bluetooth, where the services such as heterogeneous network access and seamless mobility connection are important. Even though the mobility and physical network might be varied, an efficient communication mechanism for the network access and a robust mobility management of mobile devices are needed. In this paper, we design and implement a Bluetooth system with mobile LAN access capability. The proposed system has the following features; 1) IP connection is enabled by BENP in the link layer, 2) The networks devices of heterogeneous mobile devices are integrated into a single virtual network interface, 3) IP mobility between the bluetooth and wireless LAN is supported by mobile IP. The experimented results show that the packet loss and delay time during the handover duration is reduced by predicting the handover among different networks followed by the setup of any required parameters in advance.

• Korean Journal of Crystallography
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• v.5 no.1
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• pp.33-38
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• 1994

'Heterogeneous' vapor diffusion experiments were carried out using hen egg white Iysozyme and equine serum albumin as model proteins: droplets were equilibrated against reservoir solutiorls containing an alternative precipitant which is different from results showed that the use of polyethylene glycol as an alternative precipitant instead of NaCl or ammonium sulfate reduces equilibration rate between droplet and reservoir solution. By using the heterogeneous vapor diffusion techniqlue it is possible to control the equilibration rate by adjusting the relative amounts of ionic salts and nonionic yecipitants in reservoir solutions.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.197-200
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• 2009

Since various type of wireless/mobile network likes WLAN, WIBRO, HSDPA were come to us, technology providing high quality multimedia service while user move are actively researched such as MIH (Media Independent Handover) proposed by IEEE for interworking between heterogeneous network and CMIP (Client Mobile IP), PMIP (Proxy Mobile IP) for mobility. Despite the technology about interworking and handover between heterogeneous network are actively researched, handover decision method need to be researched. In this paper we suggest a simple and effective handover method for high quality multimedia service in real wireless environment. For this, we use MIH+CMIP platform for target multimedia service to make handover decision rule in WIBRO and HSDPA networks. After apply this rule, we verified effectiveness of handover decision method through real test.

• International Journal of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.51-58
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• 2017

This paper deals with the improvement of cluster head selection method in L-SEP for heterogeneous nodes among hierarchical routing protocols of wireless sensor network. Wireless sensor networks are classified into homogeneous and heterogeneous network. In heterogeneous network, SEP, L-SEP are mainly used because cluster head selection probability is different depending on node type. But, since protocol based on SEP has different cluster head selection probabilities depending on the node type, clusters that transmit data inefficiently can be formed. to improve this, it is necessary to select the cluster head that minimizes the transmission distance of member node and the cluster head. Therefore, we propose a protocol that improve the cluster head selection method.

• Journal of information and communication convergence engineering
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• v.15 no.4
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• pp.237-243
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• 2017

This paper presents an analysis of the electromagnetic interference of a heterogeneous power bus where electromagnetic bandgap (EBG) cells are irregularly arranged. To mitigate electrical-noise coupling between high-speed circuits, the EBG structure is placed between parallel plate waveguide (PPW)-based power buses on which the noise source and victim circuits are mounted. We examine a noise suppression characteristic of the heterogeneous power bus in terms of scattering parameters. The characteristics of the dispersion and scattering parameters are compared in the sensitivity analysis of the EBG structure. Electric field distributions at significant frequencies are thoroughly examined using electromagnetic simulation based on a finite element method (FEM). The noise suppression characteristics of the heterogeneous power bus are demonstrated experimentally. The heterogeneous power bus achieves significant reduction of electrical-noise coupling compared to the homogeneous power buses that are adopted in conventional high-speed circuit design. In addition, the measurements show good agreement with the FEM simulation results.

• Journal of Communications and Networks
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• v.15 no.5
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• pp.464-468
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• 2013

The widespread use of cryptographic technologies is complicated by inconsistencies and duplication in the key management systems supporting their applications. The proliferation of key management systems or protocols also results in higher operational and infrastructure costs, and fails in interoperability. Thus, it is essential to realize key management interoperability between different and heterogeneous cryptosystems. This paper presents a practical and separable key management system for heterogeneous public-key cryptosystems. We achieve the interoperability between different cryptosystems via cryptography approaches rather than communication protocols. With our scheme, each client can freely use any kind of cryptosystemthat it likes. The proposed scheme has two advantages over the key management interoperability protocol introduced by the organization for the advancement of structured information standards. One is that all the related operations do not involve the communication protocol and thus no special restrictions are taken on the client devices. The other is that the proposed scheme does not suffer from single-point fault and bottleneck problems.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.653-654
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• 2008

A DF (Directory Facilitator) provides yellow pages services for other agents in agent platform. That is to say, the agents are able to register the descriptions of the services they provide for DF or inquire DF about the services other agents provide. The Current DF cannot federate with heterogeneous agent platforms. Because DF is not opened to the other DF in the heterogeneous agent platform, it is need to something about federation technology between them. Thus, we propose the database server for the federation technology among DFs. The main purpose of the database server is to provide the environment where agents can register their services and search about the services that other agents on the heterogeneous platform provide.

• ETRI Journal
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• v.28 no.1
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• pp.77-83
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• 2006

In order to improve the accuracy of cell selection in heterogeneous cellular systems, this paper proposes a fuzzy multiple-objective decision-based cell selection (FMDCS) strategy. Since heterogeneous cellular systems have different access technologies and multiple traffic classes, the strategy adopts cell type, data rate, coverage, transmission delay, and call arrival rate as evaluation indices, and uses different weight vectors according to the traffic classes of the mobile host. Then, a fuzzy multiple-objective decision algorithm is applied to select the optimal cell from all candidates. This paper also gives an instance analysis and simulation. The instance analysis shows FMDCS makes different selections for different traffic classes. Simulation results of the after-handoff quality-of-service (QoS) show the selected cell can provide MH optimal service.

• The Journal of Society for e-Business Studies
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• v.5 no.1
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• pp.105-122
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• 2000

Enterprise integration and virtual enterprise are practical visions of industrial information implementations in the information society. In these environments, the distributed and heterogeneous data sources should be exchanged and shared in effective and integrated way. However, the distributed and heterogeneous data sources are managed by independent and heterogeneous computer systems, thus system users and developers are faced difficulties in implementing enterprise integration environments, In this study, we designed and developed a database broker system utilizing a routing broker method to provide transparent location access mechanisms for the distributed and heterogeneous data sources. The proposed mechanism is designed to act as a middle tier between clients and multiple servers, and adopts Java, CORBA, and JDBC as its state-of-the-art techniques.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.4
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• pp.209-213
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• 2007

In this paper, we propose more efficient implementation architecture for realizing combination of heterogeneous routing protocols in wireless mesh routes. For realizing heterogeneous routing protocol in wireless mesh router, the following should be considered; which position in OS platform protocols should be implemented, how to define the common API for multiple routing protocols, how to provide architecture for providing high data transfer throughput and for supporting multi platform, and finally how to verify the throughput of protocol by using simulator. For solving those consideration, we propose HRPC(Heterogeneous Routing Protocol Coordinator) and describe the method for testing the protocols.