• Journal of Mechanical Science and Technology
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• v.18 no.8
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• pp.1368-1374
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• 2004

The remaining life estimation for the aged components in power plants as well as chemical plants are very important because mechanical properties of the components are degraded with in-service exposure time in high temperatures. Since it is difficult to take specimens from the operating components to evaluate mechanical properties of components, nondestructive techniques are needed to evaluate the degradation. In this study, test materials with several different degradation levels were prepared by isothermal aging heat treatment at $630^{\circ}C$. The DC potential drop method and destructive methods such as tensile and fracture toughness were used in order to evaluate the degradation of 1Cr-1Mo-0.25V steels. In this result, we can see that tensile strength and fracture toughness can be calculated from resistivity and it is possible to evaluate material degradation using DC potential drop method, non-destructive method.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.129-136
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• 2001

The remaining life estimation for the aged components in power plants as well as chemical plants are very important beacuse mechanical properties of the components are degraded with time of service exposure in high temperature. Since it is difficult to take specimens from the operating components to evaluate mechanical properties of components, nondestructive techniques are needed to estimate the degradation. In this study, test materials with 4 different degradation levels were prepared by isothermal aging heat treatment at $630^{\circ}C$. And the DC potential drop method and destructive methods such as tensile, $K_{IC}$ and hardness tests were used in order to evaluate the degradation of 1Cr-1Mo-0.25V steels. The objective of this study is to investigate the possibility of the application of DCPD method to estimate the material degradation, and to analyse the relationship between the electrical resistivity and the degree of material degradation.

• Journal of the Korean Wood Science and Technology
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• v.37 no.2
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• pp.137-140
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• 2009

Chromated copper arsenate (CCA), a long history of successful preservative, have raised environmental concerns. Adsorption characteristics of domestic soils for chromium, copper, and arsenic were assessed by measuring distribution coefficient ($K_d$) values of these metal components in a laboratory scale. The results revealed that $K_d$ values were higher in chromium, followed by arsenic and copper in soil matrix. Different soil matrixes resulted in varying mobilities of CCA components. The values of $K_d$ for all three metals increased with organic matter contents. The results suggest that the mobility of metal components may be very limited to the surface area adjacent to CCA-treated wood due to their fairly large distribution coefficient ($K_d$). However, the metal components would be persistent and accumulated in the soil, resulting in high chemical concentration in service area of treated wood.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.8-14
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• 2000

The remaining life estimation for the aged components in power plants as well as chemical plants are very important because mechanical properties of the components are degraded with time of service exposure in the high temperature. Since it is difficult to take specimens from the operating components to evaluate mechanical properties of components, accelerated aging technique are needed to estimate and analyse the material degradation. In the this study, test materials with 4 different degradation levels were prepared by isothermal aging heat treatment at $630^{\circ}C$. And tensile test, $k_{IC}$ test, hardness test and Scanning Electron Microscope analysis were performed in order to evaluate the degradation of 1Cr-1Mo-0.25V steels.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.600-602
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• 2003

In Korea, fire is the second frequent disaster. A total of 32,966 fires were happened in 2002, and injured 2,235 people and damaged 12 million dollars. So, we developed several components related to fire in order to decrease these victims and the amount of damage and have applied those components to Daegu Fire Agency. In this paper, we describe the developing system. It consists of 5 major components: mobile fire facility management component, web service component, fire management component, fire server, and fire application. They were developed in object-oriented computing environment, ATL/COM and Visual C++. So, they have some advantages such as high reusability, full interoperability, and easy understanding.

• Nuclear Engineering and Technology
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• v.30 no.6
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• pp.609-616
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• 1998

Cast duplex stainless steels are extensively used for primary pressure boundary components. These components are, however, embrittled due to the precipitation of $\alpha$' phase by spinodal decomposition and other processes when exposed to reactor operating temperature for a design lifetime or life extension conditions. This report presents a procedure for estimating the current condition and the residual life of safety-related stainless steel components by using ANL database and correlations. The database of Charpy impact energy suggests that CF-8M grade is the most susceptible to thermal aging and CF-3 grade is the least. Thus, the integrity of CF-8M alleys may be degraded seriously and the degree of deterioration may exceed acceptance limit after several years of service in the nuclear reactors.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2045-2050
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• 2003

This paper describes the development of service robotic systems with the Tripodal schematic control architecture. We show practical advantages of the proposed architecture by giving examples of our experience. First, we explain how to add new task using Tripodal architecture approach. The Tripodal architecture provides some crucial organizing principles and core components that are used to build the basis for the system. Thus, the newly developed behaviors, motion algorithm, knowledge, and planning schemes are arranged so as to guarantee the efficiency of the performance of components. Second, we describe the reusability and scaleability of our architecture by introducing the implementation process of the guide robot Jinny. Most of modules developed for former robots like PSR-1 and PSR-2 systems are used directly to the Jinny system without significant modification. Experimental results clearly showed that the developed strategy is useful, even if the hardware configurations as well as software algorithms are more complex and more accumulating.

• Korean Security Journal
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• no.22
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• pp.1-14
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• 2010

The purpose of this study was to analyze the difference of body composition, metabolic factor, and blood components according to job forms which are job period and job type and stress level for security guard workers. The conclusion is as follows. 1. There were lower level for the body fat with short term and higher level for the lactate with long term according to the job period. 2. There were lower level for the body fat with the field service and higher level for the lactate and stress with the field service according to the job type. In conclusion, it needs to have a continuous physical activity behavior for the security guard workers to manage for their effective health and to have a rest for the field service workers to decrease their physical and mental stress.

• The KIPS Transactions:PartD
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• v.11D no.3
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• pp.617-624
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• 2004

Recent developments in component technology enable the construction of complex software systems by assembling together off-the-shelf components However, It is still difficult to develop efficient, reliable, and dynamically configurable component-based systems. Unspecified dependencies and behavior on components often has cause the source of the trouble. Therefore, component-based software systems must maintain explicit presentations of inter-component dependence and component requirements. In this paper, I describe the design on repository of component service to deployment, status reporting, and control in component service. Through the existing researches to customize component technology, I present the algorithm that supports dynamic dependency interface in order to reuse context of application.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.5
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• pp.841-850
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• 2015

XaaS (Everything as a Service) provides re-usable, fine-grained software components like software, platform, infra across a network. Then users usually pay a fee to get access to the software components. It is a subset of cloud computing. Since XaaS is provided by centralized service providers, it can be a target of various security attacks. Specially, if XaaS becomes the target of APT (Advanced Persistent Threat) attack, many users utilizing XaaS as well as XaaS system can be exposed to serious danger. So various solutions against APT attack are proposed. However, they do not consider all aspects of security control, synthetically. In this paper, we propose overall security checkup considering technical aspect and policy aspect to securely operate XaaS.