• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.230-238
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• 1993

To develop multifunctional microorganisms for effective wastewater treatment, the cell of P. aeruginosa P1 enable to accumulate lead in its cell were conjugated with the cell of P. fluorescens S1 enable to degrade efficiently synthetic detergents. The plasmids of the P. aeruginosa P1 and the P. fluorescens S1 were found in the cell of the conjugants when determined by agarose gel electrophoresis. The conjugants obtained from P. fluorescens S1 as a recipient cell and P. aeruginosa P1 as a donor cell possessed the ability to degrade synthetic detergents as well as to accumulate lead.

• Tribology and Lubricants
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• v.11 no.3
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• pp.1-10
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• 1995

전세계적으로 환경보호의 중요성에 대한 인식이 높아짐에 따라 "환경수용성(Environmentally Acceptable) 윤활기유에"에 대한 관심도 늘어나고 있으며, 선진국에서는 이미 이에 관한 연구가 국가적인 차원에서 진행되고 있다. 환경수용성 윤활기유는 크게 식물성 오일, 동물성 오일 및 합성 윤활기유로 분류된다. 환경수용성 윤활기유의 중요한 물성으로는 기유의 화학적 조성, 물리적 및 화학적 성질에 따른 생분해성 및 산화 안정성 등을 들 수 있다. 대표적인 환경수용성 윤활기유는 정제된 유채오일과 선택적으로 합성된 에스테르오일이 점차 주목을 받고 있으며 특히 이들의 생분해성이 우수하므로 그 중요성이 증가되고 있다. 유채오일과 에스테르오일을 비교해 보면 유채오일은 공급이 충분하고 비교적 값이 싼 반면에 에스테르오일은 식물성 오일보다 윤활 안정성은 우수하나 가격이 비싼 단점 때문에 광범위하게 사용되는데 다소 문제가 되고 있다. 이러한 문제에도 불구하고 생분해성이 우수한 에스테르오일이 오늘날 환경에 해로운 영향을 미치는 광유계 윤활기유를 대체할 수 있을 것으로 추정된다. 본고에서는 환경수용서 윤활기유의 중요성과 그 종류 및 개발동향에 관하여 고찰하고자 한다. 고찰하고자 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.571-572
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• 2022

Recently, VR/AR(virtual reality/augmented reality) contents have actively increased, and various services related to VR/AR allow users to experience remote places. Also, Metaverse technologies based on VR/AR generally used to provide content in virtual spaces. In this paper, we present a technique for synthesizing virtual humans after capturing a 360-degree panorama of a remote environment, and analyze the remote environment to identify the location where it can be captured without error, and apply a method of synthesizing virtual humans. According to this paper, it is possible to provide various captured spaces such as industrial plants, medical facilities, and schools as remote communication media.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.4 s.56
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• pp.159-169
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• 2009

In this study, static loading tests and numerical analyses of the composite beam strengthened by multi-stepwise thermal prestressing method were carried out to evaluate the prestressing effect of the thermal prestressing prestress and the sectional effect of the installed cover-plate on the increase in the load-carrying capacity of composit beam. From this study, the strengthening method using multi-stepwise thermal prestressing method (TPSM) can be applied to reduce the deflection of the composite beam as well as to strengthening the composite beam by inducing the prestress in case of the occurrence in the large deflection by the insufficiency of the section properties of the composite beam. because of the expectation of the increase in the yield load and the sectional properties of the composite beam.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.145-154
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• 2009

Steel-Concrete Composite Deck with I-beam welded is lighter and easier to construct than conventional in situ reinforced concrete slabs due to the I-beam embedded in the corrugated slab. For the calculation of effective flexural rigidity of conventional reinforced concrete structures, methods suggested in Design Standard for Roads and Bridges and ACI have been used. In this paper, the calculation methods were applied to steel-concrete composite deck with I-beam welded and then results of the steel-concrete composite deck were compared with those of reinforced concrete slabs. In addition, applicability of the methods to steel-concrete composite deck with I-beam welded was estimated. In order to compare the effective flexural rigidity, flexural experiments were conducted. Fifteen slabs were built and the variables considered in the experiments were studs, length of the slab, shape of the section and connecting methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.190-195
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• 2004

In this paper, Error rate performance of Convolution coded DS-CDMA 16 QAM signal is analyzed using selective combining diversity reception techniques and maximal ratio combining diversity reception techniques under the environments of Rician fading. With the results of analysis, maximal ratio combining diversity reception techniques provides the performance improvement of about 3-8[㏈] over selective combining diversity reception techniques for the good error performance lot data communication. And it is found that a synergistic performance improvement is show to both diversity reception and Convolution coding, techniques overcoming mobile wireless data communication channel environment.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.1
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• pp.49-56
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• 2007

The existing Double T-Beams have been positively constructed in America and Europe due to their elegant appearance and simple section shapes. However, there are some problems; thery are relatively weak in the structural resistance, and need to use somewhat limited and complicated construction methods. In this paper, new composite beams made of concrete and steel are proposed, by taking adventage of their merits in an effort to solve thess controversial problems. In addition, feasibility is presented in developing composite Double T-Beams by introducing pre-stressing forces as well to enhance structural safety.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.74-84
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• 2008

To support advanced collaboration among knowledge workers distributed geographically, there have been extensive researches under the scope of ubiquitous computing environments. Especially, to cope with several known problems in traditional room-based collaboration environments such as uncomfortable sharing of visuals and documents and difficult operation of collaboration tools, several conceptual frameworks are designed and prototyped. Focusing on practical and interactive collaboration with remote nodes, in this paper, we conceptually design an agent-based service composition model for multi-party collaboration environments. The proposed model is designed to automatically discover and combine services to achieve given tasks in a collaboration environment by using high-level user commands (without the knowledge of internal architecture). Based on the service composition model, we develop a multi-agent-based management toolkit for multi-party collaboration environments. It provides easy-to-use GUI to operate various services in an environment and perform service composition algorithm to discover appropriate services and combine them. To explore the possibility of the toolkit we implement collaboration services to support video conference by using the toolkit.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.249-259
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• 2010

Synthetic environment data used in defense M&S fields, which came from various organization and source, are consumed and managed by their own native database system in distributed environment. But to manage these diverse data while interoperation in HLA/RTI environment, neutral synthetic environment data model is necessary to transmit the data between native database. By the support of DMSO, SEDRIS was developed to achieve this requirement and this specification guarantees loss-less data representation, interchange and interoperability. In this research, to use SEDRIS as a standard simulation database, base research, visualization for validation, data interchange experiment through test-bed was done. This paper shows each research case, result and future research direction, to propose standardized SEDRIS usage process.

• Journal of the Mineralogical Society of Korea
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• v.13 no.2
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• pp.65-72
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• 2000

미생물을 이용한 광물 합성은 현재 초기 연구단계에 있으나 신소재 개발측면에서 다야한 활용성을 보인다. 본 연구의 목적은 철환원 박테리아를 이용한 자철석 합성에 있어 미치는 환경조건들을 알아보는데 있다. 본 연구를 위해 지하 3-km 코아 시료에서 분리한 호열성 철 환원 박테리아인 TOR-39을 이용하였다. TOR-39은 $65^{\circ}C$에서 12시간이내에 비정질 철수화물을 환원시켜 자철석을 형성한다. 25일 동안 배양하여 형성된 자철석은 정육각형 모양으로 입자 크기는 50-100 나노미터이다. TOR-39을 이용한 자철석 합성시 적절한 조건은 pH는 7.9-8.5, Eh는 -200 mV 이하, 배양기간은 3-25일 그리고 온도는 $45-75^{\circ}C$이다. 미생물에 의한 자철석 합성은 나노미터 크기의 광물을 직접 합성하므로, 산업적으로 많은 이용 가치를 가질 것으로 본다.