• Structural Engineering and Mechanics
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• v.18 no.2
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• pp.231-246
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• 2004

In this paper, a comparison of various random vibration and deterministic dynamic analyses of cable-stayed bridges subjected to asynchronous ground motion is presented. Different random vibration methods are included to determine the dynamic behaviour of a cable-stayed bridge for various ground motion wave velocities. As a numerical example the Jindo Bridge located in South Korea is chosen and a 413 DOF mathematical model is employed for this bridge. The results obtained from a spectral analysis approach are compared with those of two random vibration based response spectrum methods and a deterministic method. The analyses suggest that the structural responses usually show important amplifications depending on the decreasing ground motion wave velocities.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1629-1631
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• 1998

Crosslinked polyethylene (XLPE) insulated cables are now widely used all over the world for extra-high voltage underground transmission systems. Prefabricated type (compression type) joint has developed in order to shorten the assembly time and lower the possibility of contamination at site by many companies in the world. For outdoor termination, to control the electric field distribution as uniform as possible, especially for the use of extra-high voltage system. much of products are adopting the oil-impregnated condensor cone type instead of electric field control element which uses the permitivity of it only (not capacitance). For Gas-immersed termination, dimension of outer insulation bushing was determined by IEC Publication 859. The highest voltage of underground power cable system is 345kV now, in Korea. We have much of experiences of the development of prefabricated type accessories for CV cable systems (154kV, 161kV, 230kV level). So it was possible to inspect the proto type of accessories for 345kV CV cable system and seems that the need time for the development of products is reduced.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.9
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• pp.782-789
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• 2018

Multi-Function Display (MFD) of Korean Utility Helicopter (KUH) displays image information(navigation, flight, topographical and maintenance information) delivered from Mission Computer (MC) during flight operation. The abnormal display of MFD such as flickering phenomenon was identified in the system development. It was solved by improving the shielding performance of the DVI cable and changing the DVI cable installation path at the first mass production. However, it was occurred again when the aircraft was operated for one or two years after delivery. It was also identified in the evaluation process of the derivative helicopters. Therefore, a comprehensive review of the aircraft system level has been performed to solve the problem of MFD malfunction at first and then a design improvement plan was derived by improving the DVI cable. In this paper, the causes of MFD anomalies are analyzed and also the process of design improvement are summarized. The validity of the improvement has been verified through the DVI cable assembly comparison test, SIL/ground/flight test.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.36-38
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• 2001

A neutron controls a nuclear fission in the core of a reactor. Drive system for in-core neutron detector is an equipment that drives the detector and cable to survey neutron flux in the reactor. The drive system introduced by this paper was designed for mock-up system and fabricated to drive two drivers that having a different function. The system consists of a driver assembly, a power transmission part, and cable storage part. And there is a control panel that contains PLC and inverter. This paper is going to introduce the design and certify the operation status of completed system by control panal. And we conducted the test for torque measurement.

• IE interfaces
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• v.12 no.4
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• pp.575-585
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• 1999

This study develops and operating software for a model plant. The model plant consists of an AS/RS system, two machining centers, an assembly line, and supplementary material handling equipments. Devices of each component are connected with the IBS RT24 DIO 16/16-T I/O module. Each I/O module communicates digital signals with the INTERBUS controller board via SUB-D 9 Connector cable. This study is a previous stage for developing an educational CIM software. Petri Nets is used for modelling the storage/retrieval of the AS/RS system, the flow of workpieces and the assembly line for parts. The operating software is coded with Microsoft Visual $C^{++}$ 5.0 and Interbus Library which is a software driver for the controller board. The operating software can be run on a MS Windows 95. Microsoft Access is used for the implementation of databases for BOM, AS/RS, and parts.

• IE interfaces
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• v.12 no.3
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• pp.395-400
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• 1999

Shipbuilding process is composed of hull construction, in which the structural body of a ship is formed, and outfitting, in which all the non-structural parts such as pipes, derricks, engines, machinery, electrical cable, etc. are manufactured, added and assembled. Hull construction can be classified into parts fabrication, block assembly and hull erection. Among them, the parts fabrication is the first manufacturing stage that produces components or zones needed for block assembly and hull construction. More specifically, the parts fabrication is performed through machining processes including marking, cutting, pressing, and/or forming. When material is entering into the parts fabrication stage, it is important for achieving the total efficiency of production to select one of production division, so-called 'bay,' as well as machine tools on which the part is fabricated. In this paper, given production quantities of parts in the fabrication stage, the problem is to optimally select machine tools and production division, such that the total flow-time is minimized as well as the workload among machines is balanced. Specifically, three mathematical models for flow-time minimization, load balance, and simultaneously considering both objectives, and a numerical example are analyzed and presented.

• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.351-358
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• 2018

In this study, we propose a method of suppressing the leakage noise signal of motor assembly through the test. The motor assembly is mounted on outside of the aircraft to rotate an antenna and must satisfy RE102 requirement on MIL-STD-461F in terms of electromagnetic interference. It is confirmed by RE102 test result hat the leakage noise signal of the equipment occurs due to external influx through the power and control cable and rotation of the motor. And it is ascertained that the part where internal/external physical shielding is difficult to rotate is the leakage path. To reduce the leakage noise signal, the electrical ground reinforcement and the electric shielding structure considering the operation of the equipment is applied and it is verified that the requirement is satisfied. Finally, we verified that required specification are met by applying circular corrugated choke with interlocking shapes and conductive grease to the noise leakage path.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.581-586
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• 2000

Gas metal arc welding(GMAW) uses a continuously fed electrode as a filler metal. The arc is shielded from atmospheric contamination by an inert gas active or inert/active gas mixture delivered through the welding gun and cable assembly. The recent research topics on $CO_2$ are welding machines are focused mainly on the reduction method of generated spatter by using new type consumable electrode metal or inverter control method. The various current waveform control methods have been researched for welding performance improvement. Until now current waveform control methods reduce to spatter occurred by instantaneous short circuiting,. but these methods is drawback that no reduce spatter occurred by arc reignition. In this paper the previous arc reignition current control method for welding performance improvement of inverter arc welding machine is studied and compared the various current control methods with the previous arc reignition current control method.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.4
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• pp.197-202
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• 2001

This paper proposes a design method for improving the disassembly by using the axiomatic approach. A product developer must design disassembly as well as assembly when designing the structure of a product. Axiomatic approach is a design tool that optimizes design. In this paper design evaluation method using information axiom sets impact variables and value function. As a result, examining the relationship between the functional requirements and evaluating the information can optimize designs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.1
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• pp.89-97
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• 2009

In this paper, a computer software for dynamic analysis of a high mobility tracked vehicle with pre/post processor is developed. Model of a tracked vehicle is composed of chassis, turret, mount, gun, and road-wheel assembly. Track is modeled as an extensible cable and the track tensions are applied on the wheels as external forces. The system equations of motion and constraint acceleration equations are derived in the joint coordinate space using the velocity transformation method. The pre and post processors are developed using the Visual C++.