• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.266-269
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• 2004

저장기간 중 통닭의 포장형태에 따른 가열감량은 저장 3일과 저장 6일에는 벌크포장은 낮고 비닐포장에서는 높아 통계적인 유의차이(p<0.05)를 보였으며, 전단력은 저장 1일보다는저장 3일이후에 증가하는 경향을 나타내었다. 보수력은 저장 3일에는 벌크포장이 가장 높아 저장 1일의 보수력과는 반대의 결과를 보였다. 총균은 저장 1일에서 포장형태와 관계없이 총균이 모두 검출되었으나 저장 3일과 6일에는 비닐포장에서는 총균이 검출되지 않았으며, 저장 9일에는 비닐포장에서 가장 많이 검출되었다. Coliform는 포장형태와 저장기간에 관계없이 거의 검출되지 않았고, E.coli도 포장형태와 저장기간에 관계없이 거의 검출되지 않았다. 지방산패도(TBARS) 값은 포장형태에 따라 차이는 없었고, 단백질변성(VBN) 값은 저장 3일에서는 벌크포장이 랩트레이 포장과 비닐포장에서 높았다.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.97-109
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• 2009

One of the main causes of asphalt rutting is high temperature of the pavement. Nevertheless, there has been few research on lowering the pavement temperature for reducing rutting. This study investigated the performance characteristics of moisture-retaining porous asphalt pavement, which is known to have a temperature reducing effect. The purpose of this study is to quantify the temperature reducing effect of moisture-retaining porous asphalt pavement and its effect of reducing rutting through Accelerated Pavement Testing(APT). Additionally, the possibility of reducing the thickness of the pavement in comparison to general dense grade pavement by analyzing structural layer coefficient of moisture retaining pavement. A total of three test sections consisting of two moisture-retaining porous asphalt pavement sections and one general dense-grade porous asphalt pavement section were constructed for this study. Heating and spraying of water were carried out in a regular cycle. The loading condition was 8.2 ton of wheel load, the tire pressure of $7.03kgf/cm^2$, and the contact area of $610cm^2$. The result of this experiment revealed that the temperature reducing effect of the pavement was about $6.6{\sim}7.9^{\circ}C$(average of $7.4^{\circ}C$) for the middle layer and $7.9{\sim}9.8^{\circ}C$(average of $8.8^{\circ}C$) for surface course, resulting in a rutting reduction of 26% at the pavement surface. Additionally, the structural layer coefficient of moisture retaining pavement measured from a laboratory test was 0.173, about 1.2 times that of general dense grade pavement. The general dense-grade porous asphalt pavement test section exhibited rutting at all layers of surface course, middle layer, and base layer, while the test sections of moisture-retaining porous asphalt pavement manifested rutting mostly at surface course only.

• International Journal of Highway Engineering
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• v.3 no.2 s.8
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• pp.141-147
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• 2001

Maintenance cost for managing the whole network of Expressway system in Korea increases rapidly with the increase of the total length of the system. Implementation of the Pavement Management System(PMS) is essential for efficient management of the Expressway with a limited budget. The purpose of this study is to develop the main algorithm of PMS for Korea Expressway System and to associate the algorithm with database and the Highway Geographic Information System(HGIS) recently developed. Emphasis is laid on developing the algorithm as easy as possible, so that the users can use the PMS without practical difficulty. PMS is not the decision maker, but just a supporting system for the user. The algorithm is designed in such a way that the users can modify the decision criteria if necessary. The user is the one who makes the final decision of the priority and the maintenance alternatives. The users can also inquire the current condition of the whole Expressway network in detail by association of the database and the algorithm with HGIS.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.69-79
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• 2008

This study presents the test results on the performance and the moisture retaining ability of semi rigid pavement using the moisture retaining grouting. The two kinds of the grouting materials were used for the Laboratory tests. The method of the tests includes the compression(3 hours and 7 days) and flexural strength(7 days) varying the P lot flow values. The test results show that the variation of the P lot value has no great effects on the strength, however, the different strength was found as the different grouting materials were used. The performance of the semi rigid pavement was evaluated varying the air void ration of the base asphalt pavement. The test results show that the flexural strength of the semi rigid pavement increases with increasing the air void of the base asphalt pavement so that the flexural strength of the semi rigid asphalt pavement can be effected by the air void of the base asphalt pavement. The moisture retaining tests were conducted and compared in the field the comparisons were made with the dense grade asphalt pavement and the semi rigid asphalt pavement with and without spraying the water. The difference of the temperature of the semi rigid pavement with the spraying water has recorded $11^{\circ}C$ when it compared with the dense grade asphalt pavement and $4^{\circ}C$, when it compared with the semi rigid pavement without the spraying the water. It can be seen that decrease the temperature of the pavement by the moisture retaining ability from the semi rigid pavement.

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.59-67
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• 2012

This study presents the evaluation of the patching materials that are used to repair the distress of asphalt pavement. Four kinds of patching materials currently used in practice were tested in both laboratory and field. The laboratory tests included the dry and soaked Marshall stability test, indirect tensile test, wheel tracking test and adhesive strength between the asphalt pavement and the repairing material was tested as a performance test. The field study was conducted using the slab samples placed on the location of vehicle tire passing and the performance of the repairing materials were investigated as passing the traffic load. The result of the laboratory tests were satisfied with the current design criteria and material standard except for water-immersion stability. Type C patching material showed the highest adhesive shear strength among the patching materials tested. However, the mature distress, such as rutting and stripping were monitored after construction in 10 days. It was found that performance of patching material is lack of quality behavior when they were applied in the field and required to develop and applu to prevent the mature distress of the current patching materials.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.288-295
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• 2011

The objective of this study is to develop a proper absorbent-pervious pavement. By using single graded aggregates and SAP, permeability and water absorbability of absorbent-pervious pavement are improved, and also temperature reducing effect is found out. And several tests such as compressive and flexural strength tests, and permeability/water absorption tests of absorbent-pervious pavement are carried out to verify these kind of effects. The compressive and flexural strengths are increased according to decrease of single graded aggregate size, and increase of SAP content. And the volume of water retention and absorbability are increased according to the increase of SAP content and these are also increased in small size of single graded aggregate. And about $20^{\circ}C$ of difference is observed in surface temperature between normal asphalt pavement and absorbent-pervious pavement.

• International Journal of Highway Engineering
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• v.12 no.2
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• pp.123-127
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• 2010

In this study, the profiles of optimized rehabilitated section was measured by a lightweight inertial profiler, and pavement smoothness was evaluated. To analyze the repeatability of the used lightweight profiler, two repeatable measurements were conducted. The agreement between two repeatable measurements were evaluated by Cross-correlation function. Pavement smoothness of the optimized rehabilitated pavement section and existing area was compared in terms of International Roughness Index and Profilograh Index. In general, the pavement smoothness of the rehabilitated sections was not good compared to the existing pavement sections. The analysis results could be used for the evaluation of pavement smoothness of the optimized rehabilitated pavement sections.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.63-72
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• 2009

This study aims at establishing the decision-making support system for the highway assets, long-term performance presumption and evaluation of asset value, which are appropriate for Korea, and proposing the methods of the optimal engineering method and the timing decision for the preventive maintenance through the project evaluation, the optimization method and life-cycle analysis related to the highways. In order to supplement the current problem of the near-sighted budget management system, which chooses the maintenance place of the highway, depending on the level of the budget with fixed amount, the long-term required budget prediction system and the economy principle were introduced, so that the pavement agency can predict the level of the required budget, and it was aimed to develop the pavement asset evaluation system to maintain the performance of the highway with the minimum of the cost. In the use of the highway pavement asset evaluation system, to maintain the appropriate level of the pavement evaluation index, when the budget was efficiently established in the reference of the required maintenance budget for the chosen section of the highway in the year concerned, it was possible to analyze the most rational pavement maintenance budget. With this result, it is estimated to prevent the unnecessary waste of budget in advance, and through the development of the decision-making system for the long-term performance presumption and the asset value estimation of the pavement, it is expected to able to analyze the previous evaluation of the project related to the highway and the feasibility of introduction.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.207-221
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• 2011

More than sixty percentage of highway in South Korea were constructed by concrete pavements and more than half of the concrete pavements were twenty years or older. The most of highway have difficulty in providing detour due to the traffic and road condition of South Korea. So far, asphalt concrete has been used for the overlay of aged cement concrete pavement. However, the frequent early damage and maintenance of typical asphalt overlay due to repetitive maintenance causes inconvenience of road users and expensive costs. It is necessary to investigate the factors affecting the performance of asphalt concrete overlay to improve the performance of asphalt overlay. However, the performance data of asphalt concrete overlay in South Korea does not exist. In this research, to investigate on the factors affecting the life of asphalt concrete overlay was attempted based on statistical analysis of the performance data of asphalt concrete overlay included in LTPP (Long-Term Pavement Performance) Database of U.S.A.

• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.255-262
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• 2001

랩포장 및 진공포장이 냉장 돈육이 저장성에 미치는 영향을 조사하기 위해 돈육의 등심부의를 랩포장 및 진공포장한 후 냉장저장하면서 저장기간에 따른 세균수,휘발성 염기질소, pH, 보수력 드립감량, 가열감량 및 경도의 변화를 측정하였다. 랩포장의 경우 일반세균수는 저장 10일에 2.0$\times$$10^{7}$ CGU/㎤의 수준에 달하였고, 휘발성 염기질소 함량은 저장 15d일에 26mg%로서 식육의 부패수준인 20mg%를 초과하였으며 , pH는 저장 7일 이후 급속하게 증가되어 저장 10일에 5.98의 수준이었다. 반면에 진공포장의 경우에는 일반세균수가 저장 30일에 7.7$\times$$10^{6}$ CGU/㎤의수준에 달하였고, 휘발성 염기질소 함량은 저장 30일에 19.8mg%로서 부패수준인 20mg%에 근접하였으며, pH는 저장기간이 경과됨에 따라 매우 완만하게 증가되어 저장 30일에 pH5.75의 수준이었다. 보수력은 저장 1일에는두 시험구가 75.0%의 수준으로 비슷하였으나, 저장기간이 경과됨에 따라 랩포장이 진공포장에 비해 급속하게 증가되었다. 드립감량과 가열감량은 저장초기인 저장 7일까지는 진공포장이 랩포장에 비해 다소 높은 수준이었으나 그 이후에는 랩 포장이 높은 수준이었다. 경도는 두 시험구 모두 저장 1일에 가장 높았고, 저장 기간이 경과됨에 따라 점차 저하되었으며, 랩포장에 비해 전공포장이 비교적 완만하게 저하되었다.