• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.2
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• pp.225-231
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• 2016

A military vehicle is driven at different usage modes with the army application and servicing conditions. For practical durability validation, DT(Development Test) on a new military vehicle should be run up to the durability target kilometers on test courses in the specified proving ground. Driving velocities with test courses at the endurance mode of DT are established definitely. However, OT(Operational Test) and initial endurance test of production car can't be performed only in the DT courses due to the development period limit. Therefore, this paper focuses on the method to analyze the relative road damages between the endurance test in DT and other endurance test. Road load acquisition tests on KLTV(Korean Light Tactical Vehicle) were implemented at 15 driving modes in off-road and cross-country courses of two tests. Wheel accelerations were processed through band-pass filter, and then the main frequency and maximum power of the signals were computed by PSD analysis. Finally, using the proving ground optimization based on RDS(Relative Damage Spectrum) characterization, the damage factors between off-roads of test courses were determined.

• Journal of Biosystems Engineering
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• v.23 no.5
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• pp.417-426
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• 1998

This study was intended to investigate the characteristics of loads acting on the transmission of agricultural tractors during plowing, rotavating and transporting operations. A survey was conducted to determine working speeds and transmission gears most frequently used for each operations. The transmission loads were measured at the input shaft of the transmission gear box during each operations. Time histories of the measured torque loads were converted into a load spectrum and analyzed with respect to the S-N curve of the shaft material to estimate the partial damages on the transmission. Finally, comparison of the relative damages and severeness of each operation was presented and discussed.

• Polymer(Korea)
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• v.29 no.1
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• pp.48-53
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• 2005

Tire wear is one of the factors that most drivers have concerned and is closely related to the tire life. It is very difficult to predict tire wear because the factors affecting tire wear seem to be very comlicated. Tire wear test should be performed at real conditions for the evaluation of tire wear. In this study, we analyze tire wear according to the severities of test courses by using the dedicated test method, more severe than real driving conditions. In order to simplify the factors affecting tire wear, we define roads’ driving severities to be driving severity numbers, DSNs which are obtained by measuring the lateral accelerations of test courses. And we compared tire wear rates and profiles with DSNs. These test results can provide the tire design guide to meet tire wear performance.

• Journal of KSNVE
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• v.26 no.4
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• pp.21-24
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• 2016

• Journal of the Korean Society for Precision Engineering
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• v.24 no.1 s.190
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• pp.37-46
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• 2007

The vibration environment essentially companied by vehicle operation on the ground is determined by the shape of road surface, which is called profile. This paper focuses on development of a profile and severity measurement system for unpaved test courses. In general, the profile and severity of unpaved road is an important issue in the reliability of endurance test. In order to measure unpaved road profile and severity, it is necessary to develop a profilometer system. The developed profilometer system is composed of data processing computer, power unit, air compressor and sensors(encoder, vertical gyro and laser displacement) This paper presents the measuring system configuration, measurement principle of road profile and analysis method of road characteristics used at CPG(Changwon Proving Ground) for this purpose.

• Journal of Biosystems Engineering
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• v.24 no.4
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• pp.293-300
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• 1999

The objectives of this study were to analyze the load acting on the transmission when tractor performed rotary operations in the poorly drained paddy fields and to compare its severeness with those obtained under different operational conditions. The loads were measured at the input shaft of the transmission and the load spectrum was constructed using the rain-flow cycle counting method. The severeness of the loads was represented by the partial damage sum which was determined by suing the modified Miner's rule. In the field with a shallow hardpan PTO speed affected severeness of the rotary operations greater than the forward speed did. In the field with deep hardpan, on the other hand, the effect of the forward speed was greater. the severeness in the well drained fields did not differ significantly from that in the field with a shallow hardpan. The severest load was recorded in the field with a deep hardpan.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.2 s.191
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• pp.47-57
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• 2007

The vibration environment essentially companied by vehicle operation on the road is determined by the shape of road surface, which is called profile. In general, the profile and severity of unpaved road is an important issue in the reliability of durability test for vehicles. In order to maintain severity of unpaved road, it is necessary to develop profilometer system. We developed profilometer system which is composed of data processing computer, power unit, air compressor and sensors. This paper focuses on the severity management of unpaved test courses using neural networks. This paper presents the maintenance range for cross-country course in CPG(Chang-won Proving Ground) and the evaluation of similarity degree between unpaved roads.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.154-161
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• 1995

There are several kinds of driving conditions according to the characteristic of each vehicle diver. Automaker produces vehicle strong enough to satisfy this several driving conditions at the point of vehicle durability. In order to develop the car in a short period, Automaker engineer tests vehicle at serveral accelerated durability test roads. Before testing the vehicle durability, test engineer must know how much this test road severe than general field road which is composed of high way, city road, paved road and unpaved road. This paper suggests two types of road severity test method that is using relative fatigue life prediction method and using absolute fatigue life prediction method, and also present the merits and demerits of two test methods.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.13-16
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• 2005

원자력발전소의 안전과 관련된 기기는 원전의 정상상태 운전조건뿐만 아니라 원전의 설계기준사고 조건에서도 기기의 안전관련 기능을 충분하게 수행할 수 있음이 입증되어야만 한다. 아울러 기기의 설치 환경은 원전의 설계기준사고조건(DBE))으로서 지진만이 고려되는 온화한 환경(mild zone)과 냉각재상실사고(LOCA) 주증기관파단사고(MSLB) 등과 같이 고온, 고압 등의 환경요건이 급격히 변화하는 가혹한 환경(harsh zone)으로 구별되므로 안전관련 기기의 검증 또한 이러한 환경요건에 따라 수행되어져야 한다. 본 연구에서는 당사가 개발한 가혹환경용 안전관련 고압전동기의 개발사례를 중심으로 가혹환경요건에 대한 기기의 검증절차와 방법을 제시하였다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.12a
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• pp.53-59
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• 1999