• Journal of Powder Materials
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• v.10 no.3
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• pp.151-156
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• 2003

In the present work some properties of nanopowders and possible areas of their applications are discussed. Main attention is paid to the use of nanodispersed powders (NDP) in new materials production technologies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.165-172
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• 1988

An optimal network design method using continuous form of design variables is considered. Modified Hooke-and-Jeeves algorithm has been implemented in order to solve nonlinear progamming problem which is approximately equivalent to the real network design problem (NDP) with system. efficiency criteria(i. e. travel time and costs) and construction cost as objective function. Various forms of construction cost function, locations of initial solution, and dimension of initial step size of link improvement are taken into account to show the validity of this approach. The results obtained are quite promising in terms of the numbers of evaluations in solving NDP, and the speed of convergence. Finally, some techniques in choosing efficient intial solution, initial step size and approximation are given.

• The KIPS Transactions:PartC
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• v.12C no.6 s.102
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• pp.809-816
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• 2005

MANET(mobile ad hoc network) cn be one of the access networks of BcN(broadband convergence network), and an user node requires address auto-configuration protocol for mu14i-hop environment. Some address auto-configuration protocols are proposed for independent MANET, but they don't consider BcN-accessable MANET environment. In this paper, new address auto-configuration protocol for wireless nodes is proposed. With this proposal, they ran configure their global addresses automatically in hybrid MANETs as BcN access networks. The autoconfiguration protocol modifies IPv6 NDP(neighbor discovery protocol) messages to deliver global prefix information to all wireless nodes, and avoids message boradcasting to minimize network overhead.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.753-760
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• 2017

In this paper, we propose a new method to improve the performance of a Quorum-based NDP (Neighbor Discovery Protocol) in heterogeneous wireless sensor networks. It creates a new set of discovery schedules by combining two different Quorum-based matrices. The original Quorum-based schedule guarantees only two overlapping active slots with a cycle, but the newly created matrix greatly increases the chance of neighbor discovery. Therefore, although the size of the combined matrix of the proposed method increases, the number of discovery chances with neighboring nodes considerably increases, and the new approach is superior to the original Quorum-based neighbor node discovery protocol. In this study, we compares the performance of the proposed method to the Quorum-based protocols such as SearchLight and Hedis using TOSSIM. We assume all sensor nodes operates in a different duty cycle in the experiment. The experimental results show that the proposed algorithm is superior to other Quorum-based methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.220-223
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• 2016

Explosive growth of smartphone-based mobile nodes has increased exponentially the mobile data traffic on the Internet. To reduce the traffic load on the network and to support the seamless mobility of the mobile nodes, the IETF and 3GPP have standardized a number of mobility management mechanisms. More recently, they are making an effort to find some schemes to distribute the networking systems that involve in the mobility management in order to assure the scalability and the reliability of the network. In IETF, DMM concept for the distributed mobility management on the Internet is being discussed. Specifically, the DMM can be classified into the partially distributed management and fully distributed management. In this paper, we propose a fully distributed mobility management scheme (FuDMM) on PMIPv6-based network by applying the extended NDP. We also present the performance of FuDMM using the comparative analysis with the existing ones.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.481-484
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• 2000

In this paper, we describe the design and implementation of IPv6 LAN. The legacy protocol for Internet is IPv4(IP version 4). The ability of IPv4 is not enough for modern real time multimedia communication services. So IPv6(IP version 6) protocol was suggested to resolve the problems of IPv4. We implemented IPv6 LAN using sTLA(sub Top Level Aggregation identifier) address and KOREN(KOrea Research and Experimental Network). Our IPv6 LAN is connected with 6TAP(Chicago), WIDE(Tokyo), and SingAREN(Singapore). We used a dedicated router, Windows 2000 PC host FreeBSD PC host, Solaris 7 workstation and Solaris 8 workstation for IPv6 NDP(Neighbor Discovery Protocol) protocol test. To support all data services including voice and video, IP protocol should be enhanced because the characteristics of modern network services are requiring QoS(Quality of Service) functions, auto-configuration, security, mobility and so on. So a new IP protocol, IPv6, has been developing to meet the requirements. In this paper, we introduce the implementation method and configuration information of IPv6 LAN.

• Journal of the military operations research society of Korea
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• v.30 no.1
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• pp.30-47
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• 2004

This research considers a Network Diversion Problem (NDP) in the directed graph, which is to identify a minimum cost set of links to cut so that any communication paths from a designated source node to a destination node must include at least one link from a specified set of arcs which is called the diversion arcs. We identify a redundant constraint from an earlier formulation. The problem is known to be NP-hard, however a detailed proof has not been given. We provide the proof of the NP-hardness of this problem. We develop a tabu search algorithm that includes a preprocessing procedure with two steps for removing diversion arcs as well as reducing the problem size. Computational results of the algorithm on instances of general graphs and grid graphs are reported.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.04a
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• pp.78-78
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• 2005

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.11-20
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• 2020

Quercetin and its derivatives are important metabolites that belong to the flavonol class of flavonoids. Quercetin and some of the conjugates have been approved by the FDA for human use. They are widely distributed among plants and have various biological activities, such as being anticancer, antiviral, and antioxidant. Hence, the biosynthesis of novel derivatives is an important field of research. Glycosylation and methylation are two important modification strategies that have long been used and have resulted in many novel metabolites that are not present in natural sources. A strategy for modifying quercetin in E. coli by means of glycosylation, for example, involves overexpressing respective glycosyltransferases (GTs) in the host and metabolic engineering for increasing nucleoside diphosphate sugar (NDP-sugar). Still others have used microorganisms other than E. coli, such as Streptomyces sp., for the biotransformation process. The overall study of the structural activity relationship has revealed that modification of some residues in quercetin decreased one activity but increased others. This review summarizes all of the information mentioned above.

• Toxicological Research
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• v.7 no.1
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• pp.21-27
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• 1991

We developed a simple method to determine benzodiazepines in biological samples using electron capature detectors and nitrogen-phosphorous detectors. The extraction of 13 benezodiazepines in urine at pH 9.5 with toluene and its analysis in GC/NPD showed the peaks in 9-16 min. In this retention time range, the biological backaground was fairly low and the drugs could be identified in low concentrations. The benzodiazepines in urine samples were screened by the fluorescence polarization immunoassay and positive samples were confirmed by the GC/NPD method.