• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.36-43
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• 1998

We experimented turning SCM440, called difficult-to-cut materials in general, using tungsten carbon tool(PIO) in order to elevate machinability by a new cutting method. The cutting tool designed and made to study was cooled to -17$0^{\circ}C$ in about 1 minute by liquid nitrogen. Then, we operated cryogenic cutting by cooling tool with liquid nitrogen and stuided the effect about cutting force, chip thickness, surface roughness, behavior of tool wear and cutting temperature. In addition, we investigated the possibility that sur face roughness of workpiece can be predicted analyzing cutting characteristics.

• Korean Journal of Adult Nursing
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• v.16 no.1
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• pp.27-36
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• 2004

Purpose: The purpose of this study was to identify patterns and trends of hardiness studies and to suggest the direction of further research. Method : Forty-seven hardiness studies were collected through internet searching and were reviewed by some criteria. Result : The results showed that hardiness studies have increased rapidly since 1990's. Eighteen studies were thesis' for degrees and others were for non-degree research studies. All studies employed the non-experimental design, particularly correlational studies. In the sampling method, all studies used non-probability sampling. Most commonly used instrument for hardiness measurement was Pollock(1986)'s HRHS. In the majority of research, hardiness was treated both as a composite measure and 3 subscales. Hardiness-related concepts were 27 and classified into 5 categories such as health behavior, stress, adaptation, support, and others. Most common statistical technique was Pearson's correlation coefficient, followed by regression, ANOVA, path analysis. Conclusion : To be utilized as practical nursing knowledge, hardiness studies should be done with more empirical analysis such as experimental research, and Meta-analysis is needed to compare the effect size and significance of composit and 3 subscales of hardiness construct.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.43-50
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• 1998

The purpose of the paper is to protect the damage of plastic IC package with searching the cause of the fracture due to the delamination and crack when the encapsulant of plastic IC package is on viscoelastic behavior with the effect of creep on high temperature, The model for analysis is the plastic SOJ package with dimpled diepad in the IR soldering process of surface mounting technology. The risk of delamination with calculating the distribution of viscoelastic thermal stress in the package without the crack in the surface mounting process is checked. The package model with the perfect delamination between chip and diepad is chosen to estimate the resistance against fracture in thermal loading with calculating C (t)-integrals according to the change of the design. The optimum design to depress the delamination and crack is presented.

• Architectural research
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• v.17 no.2
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• pp.57-64
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• 2015

In architectural planning, previous cases of similar spatial program provide important data for architectural design. Case-based reasoning (CBR) paradigm in the field of architectural design is closely related to the designing behavior of a planner who makes use of similar architectural designs and spatial programs in the past. In CBR, spatial graph can be constituted with most fundamental data, which can provide a method of searching spatial program by using visual graphs. This study developed a system for CBR that can analyze the similarity through graph comparison and search for buildings. This is an integrated system that is able to compare space similarity of different buildings and analyze their types, in addition to the analysis on a space within a single structure.

• Journal of Environmental Impact Assessment
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• v.20 no.5
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• pp.697-703
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• 2011

The purpose of this study aims to preserve biodiversity in increasingly fragmented green patches for spatial analysis of planting on the eco-corridors and to optimize the target species, the location, width, cross section of the eco-corridors. It was suggested that eco-corridors should have to planned at early stages of road planning so that the number and locations of eco-corridors in advance. Ecological corridor is the facility to connect two habitats fragmented by road, dam, housing and industrial area. And, everyone agree that ecological corridor is important useful structural component that help animal movement in fragmented landscapes. However, ecological corridors have many problems of the recorded the size of corridor, planting species to nearby exiting vegetation species and structure. The most important facts that there are no consideration for location of animal migration and behavior using eco-corridors. This study was carried out to spatial analysis of eco-corridors location, satellite data and GIS were used to analyze for searching optimum location of the eco-corridors.

• Analytical Science and Technology
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• v.8 no.4
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• pp.745-751
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• 1995

In this paper, several simulated devices were constructed for determining components of organic vapors emitting from decorative materials, daily use chemicals and from common behavior of human beings, such as smoking and cooking. The VOCs were preconcentrated on activated carbon and then desorbed by carbon disulphide. The results were obtained by GC/MS analysis and computer searching. It can be concluded that the categories of the sources and the components of organic vapors in indoor air are very complicated, and different sources of VOCs in indoor air have their own emission characteristics.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.9
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• pp.533-539
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• 2003

Reinforcement learning (RL) has been widely used as a learning mechanism of an artificial life system. However, RL usually suffers from slow convergence to the optimum state-action sequence or a sequence of stimulus-response (SR) behaviors, and may not correctly work in non-Markov processes. In this paper, first, to cope with slow-convergence problem, if some state-action pairs are considered as disturbance for optimum sequence, then they no to be eliminated in long-term memory (LTM), where such disturbances are found by a shortest path-finding algorithm. This process is shown to let the system get an enhanced learning speed. Second, to partly solve a non-Markov problem, if a stimulus is frequently met in a searching-process, then the stimulus will be classified as a sequential percept for a non-Markov hidden state. And thus, a correct behavior for a non-Markov hidden state can be learned as in a Markov environment. To show the validity of our proposed learning technologies, several simulation result j will be illustrated.

• Journal of Korean Association for Spatial Structures
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• v.4 no.1 s.11
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• pp.39-48
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• 2004

Generally, a structural system with large inextensional deformations, or in other words, non-strained deformation is called as 'Unstable Structure', Truss-linked structures, cable structures, membrane structures and movable structures as foldable space structures etc, are included in this category. In this paper, a dynamic analysis method for unstable structural systems is presented. Governing equations for dynamic analysis of unstable truss structures with inextensional displacements are derived. Because of singularity of inverse matrixin in practical analysis of unstable structure, the generalized inverse matrix is Introduced to resolve the singular problem. Also, the RREF technique is used to get the inextensional displacement mode. Two unstable truss structures are analyzed by using presented method. Damping is not considered. From the given results, it is known that proposed method is useful to figure out the dynamic behavior of unstable truss structures.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.11
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• pp.558-565
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• 2000

In this paper, we propose a method for mitigating for mitigating the effect of voltage of voltage sag in radial power distribution systems using load transfer switching (LTS). The term of LTS is defined that the weakness load points for voltage sag transfer to the alternative source during the fault clearing practices. The sequenced of proposed LTS method is divided into the search of weakness points for voltage sag using the risk assessment model and transfer behavior of weakness points. The search of weakness point is carried out using the risk assessment model of voltage sag and Monte Carlo simulation method and the historical reliability data in Korea Electric Power Corporation (KEPCO) are also used. Through the case studies, we verify the effectiveness of proposed LTS method and present the searching method of effective application points of LTS method using the risk assessment model.

• Journal of the Korean housing association
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• v.9 no.1
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• pp.63-73
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• 1998

This study has a subject for the detached houses and mass housing ( alias dictus, Apartment) on the Dae Gu urban area, and has a process of surveying and analyzing the actual using states of dweller in the residential space and has an object of finding the behavioral pattern of the spatial using corresponded to the living activities. As its result, a cultural searching for urban housing is disciplined with the positive study for surveying the living contents emerged form the residential spaces. Limited into sleeping, eating, hosting, familiarity and family ritual, where and how the living activities is appeared according as the housing types and floor types, and what different and common features of its spatial using is possessed, is focused on this study. As Conclusion, it is found that each living activities are differed in the spatial using behavior according to the housing and floor types, but genetically are inherited by the traditional custom. Thus two behavial directions of dweller in public residential architecture have to be reconsidered in the urban housing culture.