• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.361-374
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• 2008

Recently, satellite formation flying has been a topic of significant research interest in aerospace society because it provides potential benefits compared to a large spacecraft. Some techniques have been proposed to design optimal formation trajectories minimizing fuel consumption in the process of formation configuration or reconfiguration. In this study, a method is introduced to build fuel-optimal trajectories minimizing a cost function that combines the total fuel consumption of all satellites and assignment of fuel consumption rate for each satellite. This approach is based on collocation and nonlinear programming to solve constraints for collision avoidance and the final configuration. New constraints of nonlinear equality or inequality are derived for final configuration, and nonlinear inequality constraints are established for collision avoidance. The final configuration constraints are that three or more satellites should form a projected circular orbit and make an equilateral polygon in the horizontal plane. Example scenarios, including these constraints and the cost function, are simulated by the method to generate optimal trajectories for the formation configuration and reconfiguration of multiple satellites.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.91.2-91
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• 2001

This paper describes the path planning of an autonomous mobile robot using one camera-based sequence image processing. As an assumption, all objects in front of the mobile robot are located on the same plane where robot moves. Using the moving camera grounded on the autonomous mobile robot, the robot extracts the angular points of obstacle objects, calculates the height using the assumption and discrepancy between two consecutive images. In the image processing, angular points of objects must correspond so that they deliver the size of objects. Thus, the robot passes through if the object has not the height, like the paper or the shadow projected. Otherwise, the robot passes aside if ...

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.4
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• pp.59-65
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• 1985

This paper presents a design of the PWM digital servo controller and a real-time trajectory planning algorithm and a trajectory tracking algorithm for industrial robot. To be specific, a decentralized control system with hierarchical structure for industrial robot, related hardware and software, and monitor program for convinence of user are implemented. Actually, it was recognized by experiments that continuous path control on the R4 plane was possible using the above servo controller and control algorithms.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.866-875
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• 1994

The problem of a rigid rod sliding on a rough horizontal surface in the plane is analyzed, which is commonly cited as an example of the inconsistency of rigid body frictional mechanics. The inconsistency is demonstrated by analyzing the normal reaction force at the contact point with the surface, and the concept of tangential collision is derived to resolve the inconsistency. Using the Poisson's hypothesis for the coefficient of restitution and Coulomb's law for the friction, the general methodology for solving the tangential collision is presented. The problem of the inconsistency generated in the sliding rod is completely resolved, building the concept of the tangential collision and adopting the theory of frictional impact. The result presented in this paper will obviate a generic obstacle to the development of simulation packages for planar rigid body mechanical systems with temporary contacts, and planning efficient motion strategies for robot manipulators.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.355-366
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• 1997

This paper presents a comprehensive analytical approach for determining key maneuver parameters associated with the acquisition and maintenance of the ground track for a low-earth orbit. A livearized model relating changes in the drift rate of the ground track directly to changes in the orbital semi-major axis is also developed. The effect of terrestrial atmospheric drag on the semi-major axis is also explored, being quantified through an analytical expression for the decay rate as a function of density. The non-singular Lagrange planetary equations, further simplified for nearly circular orbits, provide the desired relationships between the corrective in-plane impulsive velocity increments and the corresponding effects on the orbit elements. The resulting solution strategy offers excellent insight into the dynamics affecting the timing, magnitude, and frequency of these maneuvers. Simulations are executed for the ground track acquisition and maintenance maneuver as a pre-flight planning and analysis.

• Plant Journal
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• v.8 no.2
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• pp.70-81
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• 2012

The study aims to supplement facility management plan and safety regulations & standard of oil pipeline by searching and reviewing related regulation & standard inside and outside of the country. Korean regulation & standard is reviewed based on harbor and fishery design standard of the ministry of maritime affairs and fisheries, general technology standard of oil pipeline safety regulation, gas excavation construction and safety maintenance indicator of Korea gas corporation. Global regulation & standard is reviewed based on U.S standard inspection for offshore pipeline and Europe/Mexico standard inspection for offshore pipeline. The contents of offshore pipeline installation is inserted into pipeline sector for objected facilities of safety inspection regulation & standard and, the standard of safety inspection for offshore pipeline is newly presented into pipeline maintenance part of the planning facilities management with its inspection period and method.

• Journal of The Korea Institute of Healthcare Architecture
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• v.18 no.2
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• pp.55-64
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• 2012

Recently, our country is caused with economic growth and development and city intensive brazier being caused by industrial accident, crime accident and suicide of traffic facility, it is caused by with Western dietary life and the emergency patient is to an increase tendency. And the life increases with medical development and the medical emergency demand of the old people are increasing. Approximately 80% of the patients are non-emergent patients who receive ambulatory care and the rest 20% of the patients are serio us- emergent patients Emergency patients because non-strategy it is doing with function as imported medical treatment and provides, equipment, the operation is being impossible with manpower tribal etc.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.2
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• pp.359-370
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• 1997

We consider a facility layout problem with the objective of minimizing total transportation distance, which is the sum of rectilinear distances between facilities weighted by the frequency of trips between the facilities. It is assumed that facilities are required to have rectangular shapes and there is no empty space between the facilities in the layout. In this study, a graph theoretic heuristic is developed for the problem. In the heuristic, planar graphs are constructed to represent adjacencies between the facilities and then the graphs are converted to block layouts on a continual plane using a layout construction module. (Therefore, each graph corresponds to a layout.) An initial layout is obtained by constructing a maximal weighted planar graph and then the layout is improved by changing the planar graph. A simulated annealing algorithm is used to find a planar graph which gives the best layout. To show the performance of the proposed heuristic, computational experiments are done on randomly generated test problems and results are reported.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.54-58
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• 2008

Despite rapid social changes, there have been little distinctive or fast shifts in living space, and the kind of housing design that could address the diverse need of residents is required. In the future, complex trend that is built on a mix and match of different sorts of styles is expected to be in vogue. The introduction of natural elements and ornamental factors such as books, antiques and art works into living spaces that are artificial things is expected to contribute to helping people lead a richer and Individual life. This study attempted to present a housing design by instilling culture in an existing living space and making it fit into a new lifestyle. After the position of natural and ornamental components was fixed, a contemporary modern living space was designed, for which art works would become necessary and sufficient conditions. A plane figure of the new living space was offered, and then detailed design for each part was provided. Finally, a finalized design pattern that was suitable for the selected concept was presented.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.30-41
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• 1993

Developed in this paper is a feature based modeling system for the design of welded plat construction(WPC) which is composed of flat or bended plates represented as reference plane with a constant thickness. First, the necessity and the characteristics of the modeing system for WPC as compared with the assembly of mechanical parts are investigated. Secondly, feature library for the assembly of WPC is shown which contains several types of features like joint feature, groove feature, material feature, and precision feature. Thirdly, the assembly procedures are presented which mainly consist of both the assembly transformation and the correct assembly checking. Fourthly, weld lines of the assembled WPC are defined so that those can be used in the process planning or the manufacturing stage. Finally, a prototype by a geometric modeling software Pro/Engineer, a graphic software GL(Graphic Library), and C language on a CAD workstation IRIS.