• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.5 s.236
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• pp.689-697
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• 2005

This paper presents the reliability estimation of door hinge for home appliances, which consists of bushing and shaft. The predominant failure mechanism of bushing made of polyoxymethylene(POM) is brittle fracture due to decrease of strength caused by voids existing, and that of shaft made of acrylonitrile-butadiene-styrene(ABS) is creep due to plastic deformation caused by excessive temperature and lowering of glass transition temperature by absorbed moisture. Since the brittle fracture of bushing is overstress failure mechanism, the load-strength interference model is used to estimate the failure rate of it along with failure analysis. By the way, the creep of shaft is wearout failure mechanism, and an accelerated life test is then planned and implemented to estimate its lifetime. Through the technical review about failure mechanism, temperature and humidity are selected as accelerating variables. Assuming Weibull lifetime distribution and Eyring model, the life-stress relationship and acceleration factor, $B_{10}$ life and its lower bound with $90\%$ confidence at worst case use condition are estimated by analyzing the accelerated life test data.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.163-171
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• 2020

The condition of tire tread is a key parameter closely related to the driving safety of a vehicle, which affects the contact force of the tire for braking, accelerating and cornering. The major factor influencing the contact force is tread wear, and the more tire tread wears out, the higher risk of losing control of a vehicle exits. The tire tread condition is generally checked by visual inspection that can be easily forgotten. In this paper, we propose the intelligent tire (iTire) system that consists of an acceleration sensor, a wireless signal transmission unit and a tread classifier. In addition, we also presents classification algorithm that transforms the acceleration signal into the frequency domain and extracts the features of several frequency bands as inputs to an artificial neural network. The artificial neural network for classifying tire wear was designed with an Multiple Layer Perceptron (MLP) model. Experiments showed that tread wear classification accuracy was over 80%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.117-120
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• 1998

It is analyzed the erosing process of the polymeric insulator for outdoor use with the inclined plane method. Materials used are the different type of silicone rubber, they have the content of filler and component each other. As the content of filler added to improve the tracking and erosion resistance. It has the difference of electrical performance and erosion rate. The dry-band arc is also the parameter of accelerating erosion, and appear in the form of leakage current, and the activities of leakage current has a close relationship with the surface hydrophobicity. In this paper, the erosion growth is observed by measuring the time from the voltage application to the whole breakdown, and the erosion depth. In addition, it is measured the hydrophobicity and leakage current to be a cause of erosion by the erosion steps, studied SEM, EDX for observing the transformation of surface structure by erosing.

• Land and Housing Review
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• v.10 no.1
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• pp.1-7
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• 2019

This article assumes that the first newtown has declined in Korea. Urban regeneration projects should be implemented for regeneration for CBD in Newtown as well as small local cities. The purpose of this article is to analyze the character of the subway area and to suggest the key issues for regeneartion in the subway area. Especially focussing on the local important commercial function in 5 subway areas. As a result of analyzing 5 subway areas according to basic statistical data, field interviews, and legal decline diagnostic index, all five commercial districts showed decline. In particular, the decline of Baekseok Station area appears to be serious, and there is a key factor that attracts the decline of the commercial area such as the long - term building or the closure rate of each commercial area. In addition, the vacancy rate is increasing due to large distribution facilities in new cities, the entry of new floating facilities on the outskirts, and unsold new stores, and the recession is accelerating. In this way, the signs of decline in the core of the new city are enriched, but the current Urban Regeneration Act is a legal system with a policy goal of regeneration of small and medium cities in the provinces as a system to promote the function of core bases rather than the overall redevelopment of new cities. Therefore, preemptive response is needed for the regeneration in those areas.

• Journal of IKEEE
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• v.23 no.4
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• pp.1408-1414
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• 2019

Deep artificial neural network with transfer learning is applied to compressed sensing cardiovascular MRI. Transfer learning is a method that utilizes structure, filter kernels, and weights of the network used in prior learning for current learning or application. The transfer learning is useful in accelerating learning speed, and in generalization of the neural network when learning data is limited. From a cardiac MRI experiment, with 8 healthy volunteers, the neural network with transfer learning was able to reduce learning time by a factor of more than five compared to that with standalone learning. Using test data set, reconstructed images with transfer learning showed lower normalized mean square error and better image quality compared to those without transfer learning.

• Journal of the Korean Ceramic Society
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• v.34 no.1
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• pp.7-12
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• 1997

The wear behavior of SiC in SiC-steel sliding couple was investigated under various wear test conditions, such as solid state sliding - dry and wet air atmosphere - or lubricated sliding, sliding velocity and at-mosphere temperature. The effect of SiC fabrication process on the SiC wear rate was also studied under varying sliding velocities. Humidity of air plays a lubricating role in the solid state sliding, while the wear behavior is largely influenced by the sliding velocity, especially if the atmosphere is extremely dry. The fa-brication process of SiC and the surface roughness result in different wear rate depending on the magnitude of sliding velocity. High temperature is, among others, the most deteriorating factor of wear, thus being strongly wear-accelerating even under boundary lubrication.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.157-166
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• 2007

The Information society is accelerating it's speed of change with the IT technology at the center of it and the society as a whole is in the process of transition. The purpose of study is to reveal the information gap among the public servants of Chungbuk Province. For that reason this study on the information gap of the officers is considering the effectiveness of IT. First, A theoretical approach has been made about Information Divide. Second, the analysis of questionaire on the information divide use frequency analysis, means analysis, factor analysis, and t-test.

• Journal of Navigation and Port Research
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• v.33 no.6
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• pp.401-407
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• 2009

The improvement in the terminal productivity plays a key role for container terminals to be more competitive. The productivity of yard tractors(YT) is one of the most important factor accelerating the terminal productivity. Thus, YT pooling system is newly introduced in container terminals for increasing the YT productivity. Recently, the terminals in Korea tend to adopt YT pooling system. This paper proposes the important decision factors for YT pooling work space and several types of formulations according to states of container terminals.

• Journal of the Korean Society of Industry Convergence
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• v.13 no.4
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• pp.219-225
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• 2010

A structure of line for producing products is variously changing to be automatic and one-person Cell-Line considering the physical burden for workers in manufacturing industry of electronic goods. However, workers tend to still accuse Work-related Musculoskeletal Disorders (including shoulder, waist, hand, wrist, leg etc.) as a simply repeated work by accelerating of the production speed for productivity improvement in the assembly line. Thus manufacturing engineers in charge of changing and set up newly for an assembly line are necessary to the construct of the guideline on human engineering. Especially. There is no standardized engineering-guide and it is difficult to create the exact work environment because the risk factor analysis and the improvement for assembly line are executed once a year on the current situation. I'd like to reduce the physical burden on workers through the effective improvement of processing by the guideline on working environment fit for a characteristic on manufacturing process when the process is changed or newly installed.

• Proceedings of the Korean Reliability Society Conference
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• 2004.07a
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• pp.303-311
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• 2004

This paper presents the reliability estimation of door hinge for home appliances, which consists of bushing and shaft. The predominant failure mechanism of bushing made of polyoxymethylene(POM) is brittle fracture due to decrease of strength caused by voids existing, and that of shaft made of acrylonitrile-butadiene-styrene(ABS) is creep due to plastic deformation caused by excessive temperature and lowering of glass transition temperature by absorbed moisture. Since the brittle fracture of bushing is overstress failure mechanism, the load-strength interference model is used to estimate the failure rate of it along with failure analysis. By the way, the creep of shaft is wearout failure mechanism, and an accelerated life test is then planned and implemented to estimate its lifetime. Through the technical review about failure mechanism, temperature and humidity are selected as accelerating variables. Assuming Weibull lifetime distribution and Eyring model, the life-stress relationship and acceleration factor, B$_{10}$ life and its lower bound with 90% confidence at worst case use condition are estimated by analyzing the accelerated life test data.a.