• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.283-290
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• 2020

Porous asphalt pavement is used widely in advanced countries to reduce traffic accidents and noise. On the other hand, it is not applied widely in Korea due to concerns about its durability. This study aims to find a statistical method to improve the durability of porous asphalt pavement. A Cantabro test was selected to test the durability. The Cantabro test was performed on an asphalt mixture made of a binder and aggregate. This test was repeated three times for each of the four groups to obtain the Cantabro loss rate. The average values of each of the four groups satisfied all the reference values. In addition, through an analysis of variance (ANOVA), it was possible to quantitatively classify test groups with differences in durability, thereby finding problems and improving the durability. Furthermore, the Pay Factor method can lead to voluntary improvements in quality, and the Pay factor can be calculated through statistical analysis of limited data. Through the Pay factor, it is possible to induce definite quality improvement of the contractor and continuously improve the durability of the porous asphalt mixture by evaluating the adequacy of the quality standard.

• Journal of Drive and Control
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• v.19 no.4
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• pp.29-35
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• 2022

In this paper, we developed a workload index for monitoring the durability test using operation information of an excavator. First, the acceleration and cylinder pressure were selected as load factors by analyzing operation data. Through load correlation analysis according to each load factor, Root Mean Square (RMS) and Work Load Range (WLR) were respectively derived as a load feature representing mechanical load. In addition, the workload index was used to quantify load features. For applying the workload index to monitoring, a real-time monitoring system consisting of sensors and embedded controller was installed on the excavator and the system was integrated with a remote monitoring environment using a wireless network. Results of load monitoring and analysis verified that the developed workload index was effective from the viewpoint of the relative comparison of the workload.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.3
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• pp.198-203
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• 2016

Computer-Aided Engineering (CAE) durability analysis and experiments of an aluminum alloy brake pedal were carried out for the car lighter by die casting method. In the CAE analysis, KS standards and criteria of the Volvo Car Corporation were applied, and in the experiment, KS standards were applied. The CAE analysis results show that aluminum alloy brake pedals are stronger than the conventional steel brakes pedals because the yield strength of the aluminum alloy increased by almost 97% over that of steel. Further, the structures of the cylinder and the frame were reinforced with increasing thickness of flame and were changed to suit the die-casting process. Through a durability test based on the KS standard, the strength of a prototype of the aluminum alloy brake pedal was confirmed to be sufficient.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.259-266
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• 2008

Recently, the maintenance period of sidewalk pavement proposed in Ministry of Construction & Transportation to be extended by more than 10 years. Therefore it takes many interests in Durability and the maintenance. Beside sidewalk pavement, block pavement happened problems in parking and road less than 20km/hr about bearing capacity and durability, the maintenance. It interests about importance of environmentally friendly sidewalk pavement. It compared engineering characteristics about strength and durability through general pavement comparison with stone block pavement. It estimate bearing capacity in actual si-tu site and test site. It experimented plate bearing test and field density test. It verified about durability of pavement by construction availability of geosynthetics that is constructed by purpose of filter. Stone block pavement evaluated about application of sidewalk/road pavement on the basis of result.

• Journal of Drive and Control
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• v.14 no.1
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• pp.29-34
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• 2017

This study analyzed a life test method for a power take-off (PTO) gearbox. An engine transfers mechanical power (rotation and torque) to a hydraulic pump through a PTO Gearbox with one input shaft and three output shafts. PTO gear box durability under high loads over long time periods was tested using dynamometers. In order to reflect the rated operating conditions, power must be distributed to each output shaft, and experiments were conducted under various conditions to verify the characteristics of the distributed power. An accelerated life test was designed using speed and torque as acceleration factors. Also, efficiency tests were conducted under various load conditions. Also, a lubrication oil composition analysis was performed to analyze gearbox wear status.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.132-132
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• 2009

To achieve the commercialization of PEM fuel cell, the durability problem must be solved. Recently, many researchers have focused on this durability problem and degradation studies about membrane and electrode have been reported. But durability characteristics of gas diffusion layer is not much reported yet. Durability of GDL is very important to maintain the performance of PEM fuel cell because the main function of GDL is a path of fuel and water and the GDL degradation causes the loss of the GDL function. In this study, the degradation of GDL, especially, the mechanical degradation process was investigated with the leaching test. The effect of water dissolution was observed through the test and the amount of GDL degradation was measured with various measurement methods such as weight measurement, static contact angle measurement, scanning electron microscope. After 2,000 hours test, the GDL showed structural damage and loss of hydrophobicity.

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.269-282
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• 2018

Purpose: The purpose of this study was to improve the FRP Van's durability by analyzing the problematic parameters, redesigning the rear van, and verifying the design drafts using the CAE analysis & Rig test. Methods: The collected data through the government quality inspection and field spot check were thoroughly analyzed through the characteristics diagram and the improvement suggestions were verified by performing CAE analysis, like the dynamic stiffness, Torsional stiffness, open/close condition's strength, Full car durability and Carrying out the actual test. Results: The results of this study are as follows; The output of CAE analysis shows that improvement suggestions have considerable effects on the reinforcement of FRP structure, and the actual torsion and open/close condition durability test prove that rear van may have durable life which is equivalent to vehicle life cycle. Conclusion: The structural weakness of KLTV's FRP rear van was overcome by applying the stiffener in rear van and changing the bonding method of each FRP pieces. That suggestions were proved using CAE analysis and Rig test.

• Fashion & Textile Research Journal
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• v.25 no.3
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• pp.398-408
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• 2023

Smart clothing products can experience a decrease in performance and reliability due to various mechanical, biological, and chemical stress factors that occur throughout their life cycle. These issues can hinder consumer acceptance of the products. This study aims to enhance the reliability of smart clothing and facilitate quality control by analyzing and identifying the current status of international standardization for smart clothing and electronic textiles (e-textiles). The focus of this analysis was on the durability test methods in the use environment. Furthermore, similar standards published by different standardization organizations for durability tests were compared in depth. The study showed that a total of 27 international standards have been developed or are currently under development. The current standardization efforts mainly aim to develop functionality and durability test methods for smart clothing and e-textile products. A detailed comparison was made between two international standards (IEC 63023-204-1:2023 and AATCC TM210:2019) specifically in relation to the washing durability test method and the electrical resistance measurement standards (BS EN 16812:2016 vs AATCC EP13-2021), before and after the environmental exposure tests. Based on this comparison, several suggestions have been made and discussed for the future revision of these international standards.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.105-111
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• 2003

The three-axis road simulator is the test equipment which can simulate the standardized road conditions for the durability evaluation of automotive components such as suspensions. The road load data are collected and acquired from a vehicle test, and then these data are used to simulate road load conditions by the road simulator which consists of hydraulic actuators, link mechanism and servo controller. The link mechanism must be designed in consideration of the dynamic effect and interference during three axes motions in order to generate accurate motions. In this paper, the structural and kinematic analysis of the link mechanism is performed, and these results can be used for developing the three-axis road simulator. The three-axis road simulator provides considerable savings in cost, development time, and testing risk during developing automotive components.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.3
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• pp.240-246
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• 2022

This study was conducted to develop a domestic product for a flow control valve for a hydrogen refueling station, and a domestic prototype was manufactured and the durability performance evaluation was conducted through comparison with an imported products. The stress generated by the internal pressure was checked and safety was confirmed using a commercial structural analysis program, ABAQUS, in accordance with the withstand pressure test standards. In addition, after identifying the weak areas the fatigue life was predicted through a commercial software, fe-safe. This fatigue analysis showed that the hydrogen gas repeated test criteria were satisfied.