• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.3
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• pp.293-301
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• 2021

LTV(Light Tactical Vehicle) operating in our military requires higher levels of performance and durability to withstand harsher conditions than general vehicles, as they must travel on both rough-train and off-road as well as on public roads. Recently, LTV development is demanded a variety of test evaluations in order to satisfy ROC (Required Operational Capability) by the military requirement. However, there is no informations of driving test course for satisfying the durability performance of Korean tactical vehicle. Therefore, this study aims to provide basic data to establish reliable drive test conditions by analyzing the main maneuvering test site at the domestic and foreign country in order to select the representative drive course. These studies will provide a more scientific and systematic evaluation solution for the development of tactical vehicles, and can be effectively used to establish a certified system for military vehicle test evaluation in the future

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.741-743
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• 2004

In this paper, we describe a Control Element Drive Mechanism(CEDM) operation test using a Power Controller. By testing, we can catch the mechanical and electrical characteristics of CEDM and obtain the information about the improvement of CEDM and the design of CEDM power cabinet. The power controller for CEDM introduced in this paper can input firing angles directly into gate drive circuits of thyristors so that this method can be used to derive the maximum and minimum values of firing angles within available limits for a 3-phase half-wave rectifier. Angle inputs help us understand each coil's response characteristics. Since this power controller generates a serial sequence for CEDM insertion and withdrawal operations, we may judge whether CEDM works correctly as expected or not in each phase of a step movement.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.234-238
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• 2003

Ultra small optical drive or PCMCIA type needs a focusing actuator because or applying Blue Laser and enhancing compatibility according to disk physical specification. Based on this need, this paper presents a novel focusing actuator adapted for ultra small optical drive of PCMCIA type. The focusing actuator using Lorenz force generated consists of coil, magnets and plate springs of pivoting. The design issues of the focusing actuator are the flexibility to focus direction, the rigidity to track direction and the higher natural mode of the moving part. For settling these Issues, this paper present mechanical design, computer simulations and test results of the realized focusing actuator. Finally, suitability and usefulness of the focusing actuator was demonstrated by the comparison of simulations and test results in a view of the possibility adapted for ultra small optical drive.

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.523-529
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• 2009

The ACF(Anisotropic Conductive Film) is used for bonding Drive IC and OLED display device panel. If ACF bonding process is problem, a malfunction of line defect can occur. Because electric resistance increase between the panel and drive IC after a period of time, drive IC can not supply enough current to the panel. This paper is studied on a method of test for line defect.

• Journal of Drive and Control
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• v.20 no.3
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• pp.9-14
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• 2023

In this paper, the selection of a reliable accelerated life test code for a 2-ton forklift was accomplished by choosing the driving resistance coefficient failure-free test time based on a 10,000-hour B₁₀ life. The overall life and average equivalent load of the vehicle were then calculated based on actual driving test conditions using the selected driving resistance coefficient. The gear train's accelerated life test code was selected by adjusting the equivalent load to a torque and rotation speed that did not exceed 125%(about 75HP) of the vehicle rated power. The safety of the test standards was validated by conducting an actual accelerated life test utilizing the proposed test method in this study and comparing the test result with the corresponding theoretical value. It is anticipated that the reliability of the accelerated life test in this paper will be enhanced, by incorporating actual driving performance data collected directly from the forklift and adjusting the conditions used in developing the accelerated life test code.

• Journal of Applied Reliability
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• v.15 no.3
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• pp.139-144
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• 2015

Track drive unit adopted in the small sized excavator generally have been used in the construction equipment under the 10 tons as the driving device with forwarding and reversing of excavator. It is required to study the accelerated life test applied by over torque and speed to test the durability life test reflected the many driving modes of small sized excavator and also need to equip the comprehensive performance and life test equipments to do the various performance tests. This study had analyzed the failure modes of the components, and calculated the equivalent loads investigated the used loads in the real field conditions and elicits the acceleration factor adopted in the inverse power model. Also, this study have considered the changes of the acceleration factor and the durability test time in the case of the rotary group and the bearing through analyzing the main failure modes. It was calculated the no failure test time about 2 samples and confidence level 90% and elicited the accelerated life time 720 hours.

• Transactions of The Korea Fluid Power Systems Society
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• v.2 no.2
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• pp.1-7
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• 2005

For the reliability evaluation of the track drive unit(TDU), firstly, we analyzed the major failure modes through FMEA(failure mode & effects analysis), FTA(failure tree analysis), and 2-stage QFD(quality function deployment), and then quantitatively determined the priority order of test items. The Minitab analysis was also performed for prediction of life distribution and parameters of TDU by use of field failure data collected from 430 excavators for two years. In addition, we converted the fluctuation load in field conditions into the equivalent load, and for evaluation of the accelerated lift by the cumulative fatigues, the equivalent load is again divided into the fluctuation load by reference of test time. And then, by use of the test method in this paper, the acceleration factor(AF) of needle bearing inside planetary gear which is the most weakly designed part of TDU is achieved as 5.3. This paper presents the quantitative selection method of test items for reliability evaluation, the determination method of the accelerated life test time, and the method of non-failure test time based on a few of samples. And, we proved the propriety of the proposed methods by experiments using a TDU for a 30 ton excavator.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.856-859
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• 2003

The switched reluctance motor(SRM) drive system provides a good adjustable speed and torque characteristics. However, because of the torque production mechanism, it also has some disadvantage such as higher torque ripple and fluctuation in speed. To reduce torque ripple and to control speed precisely, digital signal processor(BSP) is adopted. The DSP TMS320F241 was used to be realized this drive system. Test results show that the suggested control system has the ability of dynamic and precise speed control.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.99-103
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• 2002

IEC 61800 is an international standard on adjustable speed electrical power drive systems, which consists of three parts. IEC 61800-1 and IEC 61800-2 apply to DC power drive systems and AC power drive systems, respectively, which include power conversion, control equipment, and also a motor or motors. IEC 61800-3 specifies EMC ( Electro Magnetic Compatibility ) requirements for adjustable speed AC or DC motor drives connected to main supplies up to AC 1,000 volts. This paper studies the standards related to EMC and the text summary of international standard IEC 61800-3 which is an EMC product standard including specific test methods.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3C
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• pp.103-108
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• 2011

In this study, the limitations of large strain resonant column and torsional shear tests apparatus are described and solutions to the limitations are also described. The limitations are rotational distance, limited torque, and measurable deformation system, respectively. To resolve the rotational distance, the bottom platen was modified. And the four-armed drive plate was modified into eight-armed drive plate and the drive coil connection was changed to obtain powerful torque.