• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.347-350
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• 1992

In this note, we propose a method for designing a robot controller which can suppress the effects of both the model uncertainty and noisy velocity measurements. The controller is an output feedback compensator of which the constant gains are given in terms of a Riccati equation and a Lyapunov equation. The controller guarantees not only uniform boundedness but uniform ultimate boundedness. The stability result is local but the region can be arbitrarily enlarged at the expense of large control gain. The control law needs neither the exact knowledge of the physical robot parameters nor clean velocity measurements.

• 전자공학회지
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• 제24권2호
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• pp.13-26
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• 1997

Throughout the world in major urban centers, the volume of vehicular traffic on roads continues to increase. ITS provides drivers with traffic information and new routing options on route In order to make them move quickly to their destinations. The higher mobility, the more productivity we gain. The ultimate goal of Intelligent Transport System is to improve mobility. ITS world is broad and quite varied, as demonstrated by ITS user services, their distinct needs, and complex Interactions and synergies. ITS ties the transportation and telecommunication worlds together. The complex world of telecommunications is evolving and expanding rapidly. Especially over the last two decades, the birth and unprecedented growth of wireless is really marvelous and further holds tremendous promise into the future. This wireless and emerging technologies will offer extensive opportunities to handle many ITS user services, and alter many of the traditional paradigms of transportation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.93-95
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• 2006

In many control system applications, the system designed must not only satisfy the damping and accuracy specifications, but the control must also yield performance that is robust to external disturbance and parameter variations. We have shown that feedback in conventional control systems has the inherent ability of reducing the effects of external disturbance and parameter variations. Unfortunately, robustness with the conventional feedback configuration is achieved only with a high loop gain, which is normally detrimental to stability. The design of intelligent, autonomous machines to perform tasks that are dull, repetitive, hazardous, or that require skill, strength, or dexterity beyond the capability of humans is the ultimate goal of robotics research. This paper prove the robust control using Analog Adaptive Resonance Theorv(ART2) Algorithm about case study.

• Journal of Korean Neurosurgical Society
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• 제66권3호
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• pp.274-280
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• 2023

Post-hemorrhagic hydrocephalus (PHH) in preterm infant is common, life-threatening and the main cause of bad developmental outcomes. Ventriculoperitoneal (VP) shunt is used as the ultimate treatment for PHH. Low birth weight and low gestational age are the combination of worse prognostic factors while the single most important prognostic factor of VP shunting is age. Aggressive and early intervention have better effect in intraventricular hemorrhage and intracranial pressures control. It reduces infection rate and brain damage resulted in delayed shunt insertion. It is extremely important to let PHH infants get older and gain weight to have internal organs to be matured before undergoing VP shunt. As premature infants undergo shunt after further growth, shunt-related complications would be reduced. So temporary surgical intervention is critical for PHH infants to have them enough time until permanently shunted.

• Steel and Composite Structures
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• 제36권2호
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• pp.119-141
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• 2020

In this paper, wavy square absorbers were experimentally and numerically investigated. Numerical simulations were performed with LS-Dyna software on 36 wavy absorbers and their crushing properties were extracted and compared with the simple one. The effect of different parameters, including wave height, wave depth, and wave type; either internal or external on the crushing characteristics were also investigated. To experimentally create corrugation to validate the numerical results, a set of steel mandrel and matrix along with press machines were used. Since the initial specimens were brittle, they were subjected to heat treatment and annealing to gain the required ductility for forming with mandrel and matrix. The annealing of aluminum shells resulted in a 76%increase in ultimate strain and a 60% and 56% decrease in yield and ultimate stresses, respectively. The results showed that with increasing half-wave height in wavy square absorbers, the maximum force was first reduced and then increased. It was also found that in the specimen with constant diameter and half-wave depth, an increment in the half-wave height led to an initial increase in efficiency, followed by a decline. According to the conducted investigations, the lowe maximum force can be observed in the specimen with zero half-wave depth as compared to those having a depth of 1 cm.

• 한국정보통신학회논문지
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• 제18권5호
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• pp.1243-1248
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• 2014

일반적으로 저피탐(Low Probability of Intercept, LPI) 레이더는 펄스레이더에 비해 매우 낮은 송신출력, 높은 안테나 이득 등으로 인해 상대방의 전자전 장비(Electronic Warfare Support, ES)에 탐지될 확률이 낮다. LPI 레이더는 RCS 감소 설계와 같이 전자파에 대한 스텔스 기법의 한 종류로, 궁극적인 목적은 상대방에게 탐지되는 거리를 줄이는 것이며 RCS 값, LPI 성능 중 한 가지라도 성능이 미흡하면 적보다 먼저 탐지되게 된다. 본 논문에서는 LPI 탑재 플랫폼의 피탐 확률 감소를 위해 고려해야할 사항을 제시하였다.

• 대한간호학회지
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• 제45권6호
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• pp.910-918
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• 2015

Purpose: Safety of humans is an important factor that affects health overall, and injuries are one of the major public-health problems in the world. The purposes of this study were to describe the International safe Community movement which contributes to the injury prevention and safety promotion all over the world, and to identify out the application and developmental strategies for Korea. Methods: A review was done of previous research, reviews, and reports on the history, concepts, basic principles, and recommendations for actions of the Safe Community. Results: For this study, the application strategies of the International Safe Community movement in Korea were examined to deduce the strengths of the safe Community program. Community-based injury prevention work according to the International Safe Community model is a successful and cost-effective way of reducing injuries in the community. Conclusion: Through the International Safe Community program, communities are able to realize a healthy community and achieve improved quality of lives for the people, which is the ultimate objective of the Safe Community model. In addition, it will contribute to the economic vitalization and gain through energy and enhancement of productivity of people.

• 경영과학
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• 제23권2호
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• pp.1-16
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• 2006

With the diffusion of the Internet, firms try to electronically collaborate with their partners in order to cut costs and gain profits. This, electronic Partnership, called 'Collaborative IT' is quite popular between large purchase enterprises and small-to-medium sized sub-contractors. This study investigates such relations. This study proposes three groups of research variables-interorganizational relationship, collaborative IT activity, and firm performance. the interorganizational relationship consists of trust, commitment, and asymmetry of commitment. Collaborative IT activity is composed of information sharing and workflow integration. The ultimate dependent variable is firm performance. It is hypothesized that the relationship factors influence the level of collaborative IT activity, while the latter in turn affects the firm performance. The relationship factors nay also directly affect the dependent variable. In addition, collaborative IT motive, as a moderating variable, may influence the causal relationship. By means of survey, ore hundred and eighty-two responses were obtained. Most sample companies are small-sized, in the manufacturing sector. The analysis of data reveals that both trust and commitment positively affects the level of collaborative IT activity, while asymmetry of commitment has negative effects. The workflow integration is significantly related with firm performance. Information sharing, however, has no signific3nt effects. Furthermore, asymmetry of commitment shows reverse relationship with firm performance. Collaborative IT motive works as a moderating variable between information sharing and firm performance. Finally, workflow integration is believed to mediate between relationship factors and firm performance.

• 한국분말재료학회지
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• 제3권4호
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• pp.271-278
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• 1996

In this study, the effect of the transition elements on the microstructure and mechanical properties of rapidly solidified Al-Mg-X alloys was investigated. As a result of the rapid solidification processing, fine equiaxed grains with a mean diameter of 2 $\mu$m were observed in these alloys. Many fine particles were found to be distributed rather homogeneously throughout the matrix with relatively large particles occasionally at grain boundaries. The ultimate tensile strengths of Al-Mg-X alloys were found to decrease rather remarkably at 150 $^{\circ}C$ without the gain of the ductility at 150 $^{\circ}C$, which may result from segregation of $\beta$ ($Al_{3}Mg_{2}$) precipitates. Fine dimples were observed on the fracture surfaces for all alloy systems and the variation of the size and shape of dimples was not observed upon alloy systems. The ductility at 530 $^{\circ}C$ was found to be ~100%, suggesting that grain boundary sliding did not contribute to ductiliy despite he grain size stabilization. The absence of superplastic behavior may be associated with low boundary misorientation in rapidly solidified Al-Mg-X alloys.

• Structural Engineering and Mechanics
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• 제4권2호
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• pp.139-148
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• 1996

Vector algorithms and the relative importance of the four basic modules (computation of element stiffness matrices, assembly of the global stiffness matrix, solution of the system of linear simultaneous equations, and calculation of stresses and strains) of a finite element computer program for inelastic analysis of reinforced concrete shells are presented. Performance of the vector program is compared with a scalar program. For a cooling tower problem, the speedup factor from the scalar to the vector program is 34 for the element stiffness matrices calculation, 25.3 for the assembly of global stiffness matrix, 27.5 for the equation solver, and 37.8 for stresses, strains and nodal forces computations on a Gray Y-MP. The overall speedup factor is 30.9. When the equation solver alone is vectorized, which is computationally the most intensive part of a finite element program, a speedup factor of only 1.9 is achieved. When the rest of the program is also vectorized, a large additional speedup factor of 15.9 is attained. Therefore, it is very important that all the modules in a nonlinear program are vectorized to gain the full potential of the supercomputers. The vector finite element computer program for inelastic analysis of RC shells with layered elements developed in the present study enabled us to perform mesh convergence studies. The vector program can be used for studying the ultimate behavior of RC shells and used as a design tool.