• Journal of the Korean Graphic Arts Communication Society
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• v.30 no.1
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• pp.59-69
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• 2012

This study is Long term preservation measures which is closely related to preserving paper records, record condition evaluation, preservation measure and is conducted as follows. As for Means to Evaluate the Deterioration and Damaged Conditions of Records, research and analysis has been made on the contamination and deterioration examples such as damage, dry, stapler, metal, contamination, acidification which are the characteristics of paper record damage types. The of Paper record is one of the key procedures to evaluate the record material and its physi-chemical status in many criteria and to suggest the best preservation method. Between 1970 and 2000, the main record materials was fine paper and OMR paper along with partly newspaper and coarse paper, whereas the main recording material was ball point pen. Overall damage and deterioration status is, for record materials between 1940 and 1960, high deterioration was found and in urgent need for preservation measure and more damages are caused by tapes, staplers and metals. As for records after 1970, there is light deterioration but needs preservation process. There are approximately 3 million records produces before 2000, and assuming that there are 30 pages per record and that 30% has been damaged or deteriorated, 27 million pages are subject to preservation process. Among damaged or deteriorated records, there are large number of records impossible to go through deacidification process so manual preservation and restoration process is necessary as well. Securing manpower having preservation and restoration skills as well as preservation equipment(deacidification process, preservation and restoration) is in urgent need.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.482-487
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• 2014

The purpose of this study (I) is to provide a new methodology for evaluating deterioration of buried pipe networks for the large-diameter old pipe improvement project currently performed by K-water. To develop a new assessment model for large-diameter pipe deterioration, this study has investigated the three representative methods for the pipe deterioration assessment such as evaluation methods 1995 and 2002, and the state evaluation method through literature reviews. The ten assessment factors were selected by considering large-diameter pipe characteristics as well as common factors with high priority in the three methods. Also, the weighting of the factors was estimated by a regression equation from experiments and analysis on domestic large-diameter pipelines and expert survey data. It is expected that the new assessment model developed by analysing the existing three models is more reliable to assess the deterioration of large-diameter pipe networks.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.205-211
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• 2014

With a development of modern industry, demand for electric power is rapidly increasing and the capacity of power transfer is required to become bigger and bigger. At power station, the high-voltage power cable is used as the only method in order to transfer electric power. In this paper, we have analyzed the deterioration characteristics of 6.6kV power cable systems in operation. For the time duration of 2000 days, we have measured the cable in operation in order to extract the data for the deterioration characteristics. By analyzing the data by means of several steps of filtering processes, we could obtain the linear relations of insulation resistances as a function of time. Furthermore, we can verify that the progress characteristics in deterioration process of 6.6kV power cable systems follows the process of heat deterioration.

• Fire Science and Engineering
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• v.33 no.1
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• pp.1-6
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• 2019

The activation energy of CPVC (Chlorinated Poly Vinyl Chloride) used for non-metallic synthetic resin piping in fire-fighting was measured by thermogravimetric analysis (TGA). The activation energy was determined using by TGA kinetic methods, such as Kissinger and Flynn-Wall-Ozawa method. The calculated activation energy was 128.07 kJ/mol (Kissinger method) and 145.60 kJ/mol (Flynn-Wall-Ozawa method). The difference in activation energies calculated by the Kissinger method and Flynn-Wall-Ozawa method was not considered to be significant considering that the different analysis methods. The combustion characteristics will be tested in a future study through an evaluation of thermal deterioration using an accelerated deterioration and air oven aging test and the lifetime of CPVC will be predicted.

• Journal of the Korea Concrete Institute
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• v.11 no.6
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• pp.121-128
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• 1999

The SHO PATCH System Mortar is a mortar shotcreting system which uses fairly small machine and equipment, and is applied for shotcrete tunnel linings, in particular for small bore tunnels of aqueducts by the TBM(Tunnel Boring Machine) method, and for reparing tunnels suffering from spring water and deterioration. This study shows the characteristics of the new mortar shotcreting system, the SHOT PATCh System Mortar, which exhibits excellent shotcrete performance.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.558-561
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• 2006

In many case, reinforced concrete structures are deteriorated by construction errors, design errors, settlement and movement, and weathering. The diagnose and repair of concrete deterioration is important for effective management of concrete structures. This manual is to provides guideline on evaluating the deterioration of the concrete in a structure and selecting an appropriate repair material and method.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.583-588
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• 2000

While a great progress has been achieved in predicting the ultimate shear strength in the RC members, it is a fact that a method in order to estimate the ductility of RC members still has to be looked for. This study theoretically predict the ductility of RC beams which fail in shear after flexural yielding by considering the deterioration of concrete strength in plastic hinge region.

• 전기의세계
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• v.20 no.2
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• pp.27-31
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• 1971

Using insulating paper (cellophan), we measured the influences of moisture abosrbed for electrical properties i.e. V.I curves which result in deteriorating due to the moisture alsorbed is related to electrical properties Considerally due to the electrolytic effects of moisture involved cellulose Gel structure, we obtained also an evaluation method of deterioration rate Caused by the moisture absorbed in insulating papers.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1453-1458
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• 2006

KTX Railway rolling stock wheel run its course to corrode, deteriorate and wear away through out the time. So it is natural that the performance and ability of wheel gets declined. The frequency characteristic analysis were accomplished to above trend and shock wave flow to wheels were examined. The result will be used to find Railway rolling stock wheel crack and maintenance method hereafter.

• Computers and Concrete
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• v.14 no.6
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• pp.727-743
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• 2014

The management of existing concrete bridges has become a major social concern in many developed countries due to the large number of bridges exhibiting signs of significant deterioration. This problem has increased the demand for effective maintenance and renewal planning. In order to implement an appropriate management procedure for a structure, a wide array of corrective strategies must be evaluated with respect to not only the condition state of each defect but also safety, economy and sustainability. This paper describes a new performance evaluation system for existing concrete bridges. The system evaluates performance based on load carrying capability and durability from the results of a visual inspection and specification data, and describes the necessity of maintenance. It categorizes all girders and slabs as either unsafe, severe deterioration, moderate deterioration, mild deterioration, or safe. The technique employs an expert system with an appropriate knowledge base in the evaluation. A characteristic feature of the system is the use of neural networks to evaluate the performance and facilitate refinement of the knowledge base. The neural network proposed in the present study has the capability to prevent an inference process and knowledge base from becoming a black box. It is very important that the system is capable of detailing how the performance is calculated since the road network represents a huge investment. The effectiveness of the neural network and machine learning method is verified by comparing diagnostic results by bridge experts.