• Journal of KIISE:Software and Applications
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• v.32 no.11
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• pp.1099-1110
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• 2005

As auctions become popular, developing good agent bidding strategies has been an important focus in agent-based electronic commerce research. Especially for the continuous double auctions where no single dominant strategy is known, the agent bidding strategy has practical significance. This paper introduces an adaptive agent strategy for the countinuous double auction. The central idea is to let the agent figure out at run time when the sophisticated strategy (called the p-strategy) is beneficial and when a simpler strategy is better. Balance between exploration and exploitation is achieved by using a heuristic exploration function that trades off the expected profits and the number of tries of each strategy. We have experimentally evaluated the performance of the adaptive strategy in a wide variety of environments. The experiment results indicate that the adaptive strategy outperforms the plain p-strategy when the p-strategy performs poorly, while it performs similar to the p-strategy when the p-strategy dominates the other simple strategies.

• Journal of the Korean institute of surface engineering
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• v.33 no.2
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• pp.126-134
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• 2000

This study investigated the bath compositions and plating conditions and crystal structure used for achieving nickel-thallium-phosphorus deposits by means electroless plating. The electroless nickel-thallium-phosphorus deposits were achieved with a bath using sodium hypophosphite as the reducing agent and sodium citrate as the complexing agent. The depositing rate was 10.5mg.$cm^{2-1}$ .$hr^{-1 }$ from the optimistic bath composition, 0.1M nickel sulfate, 0.005M thallium sulfate, 0.2M sodium hypophosphite, and 0.05M sodium citrat and the recommended plating conditions, pH 5.5 and $90^{\circ}C$. The composition of alloy deposits determined by X-ray analysis (EDS) that the Thallium was increased with major increasing concentration of complexing agent and thallium ion in bath solution, it decreased according to the increasing concentrations of reduction agent in the bath solution, Bit Phosphorus showed a contrary to the thallium. It was observed from X-ray diffraction analysis, Scanning Electron Microscopy and Transmission Electron Microscopy. The crystalline structure of deposits was amorphous at the first deposited state but it was changed $Ni-T1-Ni_{5}$ $P_2$ polycrystalline when subjected to 1 hour heat treatment of more than $350^{\circ}C$. TEM observation demonstrated that the microstructure was identical to the result of the XRD at as deposited but it became $Ni-Tl-Ni_{5}$ $P_2$ polycrystalline when heated. And grain size was 10-50nm.

• 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.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.389-393
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• 1991

A convenient method for the synthesis of indobufen, which is a potent antiinflammatory agent, was described. Ethyl 2-phenylbutyrate(4) was prepared by Friedel-Crafts reaction of benzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio)acetate(l) followed by ethylation and desulfurization of the resultant ethyl 2-(methylthio)phenylacetate(2). Ethyl 2-(p-aminophenyl)butyrate(6) was prepared by nitration of (4) and successive reduction of ethyl 2-(p-nitrophenyl) butyrate(5). Indobufen was obtained by condensation reaction of (6) with phthalic anhydride followed by reduction and hydrolysis of the resultant ethyl 2-[p-(1, 3-dioxo-2-isoindolinyl)phenyl]butyrate(7).

• Archives of Pharmacal Research
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• v.24 no.5
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• pp.397-401
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• 2001

In the search for new naturally occurring angiogenic inhibitory we found that culture broths from two unidentified fungal strains exerted potent inhibitory activities on capillary-like tube formation of human umbilical vein endothelial cells (HUVEC) in vitro. Two active compounds were isolated by bioassay-guided separation and their structures were identified as gliotoxin (1) and its derivative methylthiogliotoxin (2) by spectroscopic analyses. These compounds significantly inhibited the migration of HUVEC assessed by in vitro wounding migration assay and exhibited at least 10 times more potent inhibition of proliferation of HUVECs as compared with that of cancer cell lines such as HeLa, MCF-7, and KB 3-1 cells. Especially, gliotoxin having disulfide group exerted more potent activities than methylthiogliotoxin, suggesting that gliotoxin could be a useful compound for further study as an anti-angiogenic agent.

• 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.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.783-789
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• 2003

This study was conducted to reuse the rice straw ash as washing agent for oil contaminated soils. The results are summarized as follows. The physical characteristics of rice straw before and after burning were as follows ; In case of burning rice straw 1g, the rice straw ash was generated 0.14g and pH was changed neutrality into alkali(pH 10.9) and specific surface area was increased to five times and particle distribution was corresponded to fine silt.(under 0.05mm) The physical characteristics of rice straw ash were Carbon 10.9%, Hydrogen 1.5%, Oxygen 23.4%, Nitrogen 5.2%, Sulfate 1.2% and chemical characteristics were Si 189.2ppm, Ca 10.2ppm, Mg 4.7ppm. Oil cleanup ratio by pH variation were about 40∼50% of initial concentration of oil by pH 10∼11. As the result of cleanup comparative experiment, the rice straw ash was about 20∼30%, the tritonX-100 about 40∼50% of washing efficiency, and then in the future it will be possibility of substitute washing agent.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.27-36
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• 2007

A recent study showed that MTBE can be degraded by Fenton's Reagent (FR). The treatment of MTBE with FR, however, has a definite limitation of extremely low pH requirement (optimum pH $3{\sim}4$) that makes the process impracticable under neutral pH condition on which the ferrous ion precipitate forming salt with hydroxyl anion, which result in the diminishment of the Fenton reaction and incompatible with biological treatment. Consequently, this process using only FR is not suitable for in-situ remediation of MTBE. In order to overcome this limitation, modified Fenton process using NTA, oxalate, and acetate as chelating reagents was introduced into this study. Modified Fenton reaction, available at near neutral pH, has been researched for the purpose of obtaining high performance of oxidation efficiency with stabilized ferrous or ferric ion by chelating agent. In the MTBE degradation experiment with modified Fenton reaction, it was observed that this reaction was influenced by some factors such as concentrations of ferric ion, hydrogen peroxide, and each chelating agent and pH. Six potential chelators including oxalate, succinate, acetate, citrate, NTA, and EDTA were tested to identify an appropriate chelator. Among them, oxalate, acetate, and NTA were selected based on their remediation efficiency and biodegradability of each chelator. Using NTA, the best result was obtained, showing more than 99.9% of MTBE degradation after 30 min at pH 7; the initial concentration of hydrogen peroxide, NTA, and ferric ion were 1470 mM, 6 mM, and 2 mM, respectively. Under the same experimental condition, the removal of MTBE using oxalate and acetate were 91.3% and 75.8%, respectively. Optimum concentration of iron ion were 3 mM using oxalate which showed the greatest removal efficiency. In case of acetate, $[MTBE]_0$ decreased gradually when concentration of iron ion increased above 5 mM. In this research, it was showed that modified Fenton reaction is proper for in-situ remediation of MTBE with great efficiency and the application of chelatimg agents, such as NTA, was able to make the ferric ion stable even at near neutral pH. In consequence, the outcomes of this study clearly showed that the modified Fenton process successfully coped with the limitation of the low pH requirement. Furthermore, the introduction of low molecular weight organic acids makes the process more available since these compounds have distinguishable biodegradability and it may be able to use natural iron mineral as catalyst for in situ remediation, so as to produce hydroxyl radical without the additional injection of ferric ion.

• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.257-266
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• 2004

Mobile agents are defined as processes which can be autonomously delegated or transferred among the hosts in a network in order to perform some computations on behalf of the user and co-operate with other agents. Currently, mobile agents are used in various fields, such as electronic commerce, mobile communication, parallel processing, search of information, recovery, and so on. In pure P2P network environment, if mobile agents that require computing resources rashly migrate to another peers without consideration on the peer's capacity of resources, the peer may have a problem that the performance of the peer is degraded due to lack of resources. To solve this problem, we propose resource reservation based load balancing scheme of using RMA(Resource Management Agent) that monitors workload information of the peers and that decides migrating agents and destination peers. In mobile agent migrating procedure, if the resource of specific peer is already reserved, our resource reservation scheme prevents other mobile agents from allocating the resource.

• Corrosion Science and Technology
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• v.21 no.2
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• pp.89-99
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• 2022

A versatile method for performing non-cyanide electroless gold plating using thiomalic acid (TMA) as a complexing agent and 2-aminoethanethiol (AET) as a reducing agent was investigated. It was found that TMA was an excellent complexing agent for gold. It can be used in electroless gold plating baths at a neutral pH with a high solution stability, makes it a potential candidate to replace conventional toxic cyanide complex. It was found that one gold atomic ion could bind to two TMA molecules to form the [2TMA-Au⁺] complex in a solution. AET can be used as a reducing agent in electroless gold plating solutions. The highest current density was obtained at electrode rotation rate of 250 to 500 rpm based on anodic and cathodic polarization curves with the mixed potential theory. Increasing AET concentration, pH, and temperature significantly increased the anodic polarization current density and shifted the plating potential toward a more negative value. The optimal gold ion concentration to obtain the highest current density was 0.01 M. The cathodic current was higher at a lower pH and a higher temperature. The current density was inversely proportional to TMA concentration.