• Spatial Information Research
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• v.11 no.1
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• pp.61-72
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• 2003

LBS has attracted considerable attention with the spread of high performance mobile devices and the expansion of mobile business. Our study starts from the recognition of the problems associated with the current mobile Sales Force Automation(SFA) which is one of the application domain of LBS: they lack the capabilities such as an efficient sharing of information. This paper presents a technical framework in which the location information on the move and the mobile P2P service are utilized for the realization of truly mobile SF A platforms. Major contributions of our study include feasible prototyping of gCRM middleware via which the location-based services on the move are enabled, and a agent module involving the P2P service for mobile clients.

• Biomolecules & Therapeutics
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• v.32 no.4
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• pp.474-480
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• 2024

Streptomyces avermitilis genome includes 33 genes encoding monooxygenation-catalyzing cytochrome P450 enzymes. We investigated the structure of CYP107P2 and its interactions with terpenoid compounds. The recombinant CYP107P2 protein was expressed in Escherichia coli and the purified enzyme exhibited a typical P450 spectrum upon CO-binding in its reduced state. Type-I substrate-binding spectral titrations were observed with various terpenoid compounds, including α-pinene, β-pinene, α-terpinyl acetate, and (+)-3-carene. The calculated binding affinities (Kd) ranged from 15.9 to 50.8 µM. The X-ray crystal structure of CYP107P2 was determined at 1.99 Å resolution, with a well-conserved overall P450 folding conformation. The terpenoid compound docking models illustrated that the structural interaction between monoterpenes and CYP107P2, with the distance between heme and terpenes ranging from 3.4 to 5.4 Å, indicates potential substrate binding for P450 enzyme. This study suggests that CYP107P2 is a Streptomyces P450 enzyme capable of catalyzing terpenes as substrates, signifying noteworthy advancements in comprehending a novel P450 enzyme's involvement in terpene reactions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2B
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• pp.279-288
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• 2004

Rapidly emerging P2P(Peer to Peer) applications generate very bursty traffic, which gives a lot of burden to network, and the amount of such traffic is increasing rapidly. Thus it is becoming more important to understand the characteristics of such traffic and reflect it when we design and analyze the network. To do that we measured the traffic in a campus network and present flow statistics and traffic models of the measured traffic, and compare them with those of the web traffic. The results indicate that P2P traffic is much burstier than web traffic and as a result it negatively affects network performance. We modeled P2P traffic using self-similar traffic model to predict packet delay and loss occurred in network which are very important to evaluate network performance. We also predict queue length distribution and loss probability in SSQ(Single Sewer Queue). To assess accuracy of traffic model, we compare the SSQ statistics of traffic models with that of the traffic trace. The results show that self-similar traffic models we use can predict P2P traffic behavior in network precisely. It is expected that the traffic models we derived can be used when we design network capacity and predict network performance and QoS of the P2P applications.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.127-131
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• 2020

Objective: This study was conducted to determine catalytic properties of wheat phytase with exopolyphosphatase activity toward medium-chain and long-chain inorganic polyphosphate (polyP) substrates for comparative purpose. Methods: Exopolyphosphatase assay of wheat phytase toward polyP75 (medium-chain polyP with average 75 phosphate residues) and polyP1150 (long-chain polyP with average 1150 phosphate residues) was performed at pH 5.2 and pH 7.5. Its activity toward these substrates was investigated in the presence of Mg²⁺, Ni²⁺, Co²⁺, Mn²⁺, or ethylenediaminetetraacetic acid (EDTA). Michaelis constant (K_m) and maximum reaction velocity (V_max) were determined from Lineweaver-Burk plot with polyP75 or polyP1150. Monophosphate esterase activity toward p-nitrophenyl phosphate (pNPP) was assayed in the presence of polyP75 or polyP1150. Results: Wheat phytase dephosphorylated polyP75 and polyP1150 at pH 7.5 more effectively than that at pH 5.2. Its exopolyphosphatase activity toward polyP75 at pH 5.2 was 1.4-fold higher than that toward polyP1150 whereas its activity toward polyP75 at pH 7.5 was 1.4-fold lower than that toward polyP1150. Regarding enzyme kinetics, K_m for polyP75 was 1.4-fold lower than that for polyP1150 while V_max for polyP1150 was 2-fold higher than that for polyP75. The presence of Mg²⁺, Ni²⁺, Co²⁺, Mn²⁺, or EDTA (1 or 5 mM) exhibited no inhibitory effect on its activity toward polyP75. Its activity toward polyP1150 was inhibited by 1 mM of Ni²⁺ or Co²⁺ and 5 mM of Ni²⁺, Co²⁺, or Mg²⁺. Ni²⁺ inhibited its activity toward polyP1150 the most strongly among tested additives. Both polyP75 and polyP1150 inhibited the monophosphate esterase activity of wheat phytase toward pNPP in a dose-dependent manner. Conclusion: Wheat phytase with an unexpected exopolyphosphatase activity has potential as a therapeutic tool and a next-generational feed additive for controlling long-chain polyP-induced inappropriate inflammation from Campylobacter jejuni and Salmonella typhimurium infection in public health and animal husbandry.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.135-143
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• 2015

A Multiplayer Online Game(MOG) is a game capable of supporting hundreds or thousands of players and is mostly played using the Internet. P2P(peer-to-peer) architectures for MOGs can potentially achieve high scalability, low cost, and good performance. The basic idea of many P2P-based games is to distribute the game state among peers and along with it processing, network, and storage tasks. In a primary-copy based replication scheme where any update to the object has to be first performed on the primary copy, this means distributing primary copies of objects among peers. Most multiplayer games use a primary-copy model in order to provide strong consistency control over an object. Games consist of various types of actions that have different levels of sensitivity and can be categorized according to their consistency requirements. With the appropriate consistency level of each action type within a game, this paper allows developers to choose the right trade-off between performance and consistency. The performance for P2P game architecture with the primary-copy model is evaluated through simulation experiments and analysis.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.1
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• pp.104-109
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• 2005

Context-awareness is an important element that can provide service of good quality according to users' surrounding environment and status in ubiquitous computing environment. Information gathering tools for context-awareness use small size mobile devices which have easy movement and a mobile agent in mobile device. Now, Mobile agents are consuming much times and expense to collect and recognize each users' context information. Therefore, needs research about structure for users' context information awareness in early time to reduce mobile agent's load. This paper proposes a P2P mobile agent structure that mikes filtering techniques and a P2P agent in mobile agent. The proposed structure analyzes each user's context information in same area, and groups users who have similar preference degree. Grouped users share information using a P2P mobile agent. Also this structure observes and learns to continue on users' action and service, and measures new interrelation.

• Research in Community and Public Health Nursing
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• v.4 no.2
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• pp.131-138
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• 1993

The purpose of this study was to identify K.A.P. of industrial workers on health management. The study was conducted Dec 5, 1992 to March 10, 1993. The results were as follows : 1. The total Score of K.A.P. of industrial worker on the Knowledge of industrial health management was 2.52, the Attitude score was 42, the Practice score 2, 62. 2. The office workers' score on K.A.P.(T=-2. 11, P=.038) Attitude score(T=-2.03, P=.045) were higher than that of productive workers' 3. The K.A.P. score of married worker was higher than that of single workers, and showed significant differences statistically. 4. There are significant statistical differences in the Attitude score of workers according to age(F=2.26, F=.0304). 5. There were statistically significant differences among total Scores of K.A.P. (F=3.1141, P=.0498). Practice score(F=8.4421, P=.0004), Knowledge Score (F=3.5833, P=.0323). Performed 84.7%. 6. The relationship between industrial worker's health level score and industrial health status had reverse relationship(R=-.7689. P<.001) Therefore the companies that performed better health management attained a higher health level.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2B
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• pp.137-145
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• 2006

In this paper, we propose a multicast P2Patching technique in the application layer. The P2Patching technique serves VOD stream effectively with Patching in P2P environment. The P2Patching provides multicast tree construction technique that reduces the server load and minimizes the start delay with extended multicast technique. And we provide a fast recovery technique by tree failure and dynamic buffering scheme that guarantees the continuous streaming by frequent tree disconnections. Comparing the method with that of $P2Cast^{[12]}$, we obtained the better performance by our scheme in terms of average join count, service rejection probability, tree recovery failure and buffer starvation. The average about 16$\%$ of the improvement is shown by the simulation. Most of all, the performance of buffer starvation and average join count shows a significant improvement than that of P2Cast.

• Journal of the Korean Chemical Society
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• v.23 no.6
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• pp.349-357
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• 1979

A non-Boltzman equilibrium population of $Cl(^2P_{1/2})$ atoms has been observed in a flow discharge-atomic absorpion experiment. The rates of reactions of $Cl(^2P_{3/2})$ atoms with various substrates are in reasonable agreement with reported values determined by competition methods. The similar reactivities of both $Cl(^2P_{1/2})$ and $Cl(^2P_{3/2})$ atoms indicate that the contribution of $Cl(^2P_{1/2})$ atoms to the rate measurements in the competition experiment is small, and this negligible contribution may be the reason why the rate constants obtained by assuming single reactive species (in competition method) agree well with our direct measurement.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.578-584
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• 2003

본 논문에서는 인터넷 기반 P2P 네트워크를 이용한 Grid 컴퓨팅에서의 효율적인 보안 관리 모델을 제시한다. 하나는 P2P 네트워크를 이용한 에러 복구 과정과 다른 하나는 에이전트간 신뢰관계 구성 방안이다. 또한 P2P 네트워크에서 다양한 네트워크 간 보안 통신을 보장하기 위해 SOAP을 이용한 보안 메시지 프로토콜을 제안한다. 제안된 새로운 보안 관리 모델은 P2P 네트워크로 구성된 Grid 컴퓨팅 네트워크의 성능을 향상시킬 것으로 기대된다.