• Journal of the Society of Disaster Information
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• v.7 no.2
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• pp.87-95
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• 2011

The skid resistant of pavement surface is an important parameter since it is directly related to the traffic safety under moving vehicular loads. In particular, it should be considered as a major factor in pavement performance evaluations to reduce the traffic accident from vehicular sliding. In this study, a portable and an automatic skid resistance tests were used to evaluate the skid resistances of the in-situ pavements. The test results showed that the skid resistance of the conventional dense graded pavement was more noticeable than the other pavement types such as the drainage pavement and the stone mastic asphalt(SMA) pavement as the service life of pavement was increased.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.115-121
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• 1985

To improve methods of screening rice cultivars with field resistance to bacterial leaf blight, testing plant inoculation and neighbor plant inoculation were compared by using 33 rice cultivars. In the testing plant inoculation method, field resistance was evaluated by measuring the leaf areas diseased on the new leaves expanded after the inoculation. Varietal differences in field resistance were recognized more clearly by the testing plant inoculation method than by the neighbor plant inoculation method. Highly significant correlation was observed between the results of the two methods. Some rice cultivars such as, Seomjin, Hangangchal, Taebaeg, Samgang, Milyang 42, Asominori, Java 14, Chugoku 45 and 70X-46 showed remarkable field resistance to bacterial leaf blight. The testing plant inoculation method appeared desirable for screening rice cultivars for the qualitative and field resistance to bacterial leaf blight because of using less labor and less field area than neighbor plant inoculation.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.50-55
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• 2006

A field-resistant strain of the diamondback-moth(Plutella xylostella L.), collected from Chinese cabbage alpine farmland at Gangwon-do, Korea, was used for determination of the characteristics of resistance to chlorpyrifos using the activities of esterases and glutathione-S-transferase(GST), protein sequestration and AChE insenstivity. Although the activities of esterases extracted from resistant strain and susceptible strain were not significantly different, isozyme bands shown on the electrophoresis were different. GST activity from field resistant strain was 1.5-fold higher than that of susceptible. No differences were shown between resistant and susceptible ones in protein sequestration. The insensitivities of AChE to chlorpyrifos, however, extracted from susceptible strain was 460-fold higher than those of resistant. These results indicated that the insensitivity of AChE is the major factor for developing the resistance and activities of GST might be a minor factor.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.285-292
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• 2006

The objective of this study is to introduce the development of the first Korean full-scale APT(Accelerated Pavement Tester) and to compare the performances of general dense grade asphalt mixture and modified asphalt mixtures as the first running of the tester. The tests evaluated the rutting resistance for dense grade mixture and three different modified asphalt mixture under three different temperature conditions (25-30, 40, $50^{\circ}C$). The results of the testing were compared with the laboratory test results. Results of the tests indicated that the all the modified asphalt sections showed higher rutting resistance than the dense grade section. Especially, the difference was more noticeable at higher temperature condition. Additionally, $G^*/sin{\delta}$ is found out to be an important factor for permanent deformation prediction whereas the resilient modulus was not.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1D
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• pp.33-39
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• 2012

More and more pavements are suffering from damage these days due to the below-zero winter temperatures and frequent snowfalls. From this research, the freeze-thawing mechanisms of pavements will be observed, and the freeze-thawing resistance of porous asphalt concrete mixture is to be evaluated according to various assessment methods. The investigation was conducted through applying rigid and flexible pavements to freeze-thawing resistance experiments, which include various experiments such as deformation rate measurements, Lottman tests, repeated cyclic freeze-thawing experiments, stripping resistance tests and so on. Test results revealed that the porous asphalt concrete had less deformations according to temperatures compared to dense-graded asphalt concrete due to the 20% void gap. In addition, according to the freeze-thawing repetition experiments which are effected by moisture, the porous asphalt concrete mixture showed superior resistance to repeated cyclic freeze-thawing compared to other asphalt concrete mixtures due to the drainage and the voids within the specimen.

• Journal of the Korean Geotechnical Society
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• v.20 no.1
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• pp.13-19
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• 2004

The major distress types in the domestic asphalt pavement are fatigue cracking, reflection cracking, thermal cracking, and rutting. To decrease the pavement distress by reinforcing asphalt pavement with reinforcement interlayer in geosynthetics to the traditional pavement systems can improve these problems. This study conducted laboratory test with asphalt pavement reinforced by glass fiber sheet to fix systematically geosynthetic asphalt pavement system. Laboratory tests like wheel tracking test and crack resistance test are conducted to analyze the controlling effect of glass fiber sheet on cracking and rutting of asphalt pavement.

• The Journal of Engineering Geology
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• v.34 no.2
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• pp.295-315
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• 2024

Urban development and the expansion of electrical resistivity surveying applications have increased the need for soil and underground structure investigations on paved surfaces. Traditional methods involved drilling through the pavement or surveying surrounding soil. Recently, non-invasive surveying techniques have been developed. This paper analyzes these methods, categorizing them into galvanic methods (including drilling and flat ground electrodes) and capacitive coupling methods. By examining case studies, it suggests selecting the appropriate method based on the pros and cons of each and the specific site characteristics. The paper also discusses the applicability and limitations of electrical resistivity surveying through various examples.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.191-198
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• 2001

국내 도로포장의 주요 파손형태는 주변환경 및 반복 교통하중 조건에 의한 소성변형(rutting), 피로균열, 반사균열, 온도균열 등이 있는데, 포장이 설계수명에 도달하기 이전에 주로 발생하며 이로 인한 도로포장의 유지관리에 막대한 국가예산이 낭비되고 있는 실정이다. 본 연구에서는 토목섬유 아스팔트 포장 시스템을 체계적으로 정립하기 위해 휠트래킹 시험과 균열저항성 시험을 수행하여 토목섬유 아스팔트 포장의 소성변형 및 균열 저항성을 분석하였다. 이러한 실험결과를 통해 아스팔트 포장에서의 토목섬유 보강 효과가 평가되었다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.79-85
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• 2023

Skid resistance pavement is an accessory to the road and is a facility for the safe driving of cars by increasing the skid resistance of road pavement. In particular, in bad weather conditions such as snow, rain, and black ice, the skid resistance performance of skid resistance pavement greatly affects the safety of road traffic and drivers. However, BPT(British Pendulum Tester) has a test area of only 0.009 m², making it difficult to represent the overall packaging surface. A reliable method of evaluating slip resistance performance is needed for maintaining non-slip packaging. In this study, the conventional BPT test and the skid resistance performance evaluation method of the PFT(Pavement Friction Tester) and µGT(Micro Grip Tester) tests were compared through guidelines and standard investigations and applied to the field skid resistance performance evaluation. In addition, skid resistance pavement with different skid resistance performance was installed at the test-bed and actual road demonstration sites to compare BPN(British Pendulum Number), SN(Skid Number), GN(Grip Number), and to derive correlations for each performance evaluation method. As a result of the experiment, SN and GN showed similar skid resistance performance, and the GN value was derived similar to BPN × 0.01.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.50-50
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• 2002

배추무사마귀병 저항성 유전 양식을 증명하기 위해서 CR계 F1에서 유래된 F2 세대를 포장시험과 유묘 검정을 실시하였다. F$_2$ 세대의 7 집단은 단인자우성으로 3:1의 분리비를 보였고, 5 집단은 중복 유전자가 관여하는 9:7의 유전 분리비를 보였다. 배추무사마귀병 저항성 유전자와 연관된 DNA 마커를 개발하기 위하여 CR-Saerona F$_2$ 집단을 배추무사마귀병 발병포장에서 재배하여 저항성 평가를 하였다. 220개의 임의의 프라이머를 이용하여 BSA-RAPD (Bulked segregant analysis-Randomly amplified polymorphic DNA)를 수행하였지만 CR-Saerona F2 집단에서 배추무사마귀병 저항성 유전자와 꼭 들어맞는 DNA 마커는 발견되지 않았다. 300개의 임의의 프라이머를 이용하여 CR-Saerona에서 유래된 F$_2$ 세대를 QTL 분석하였다. 저항성 정도는 발병지수에 따라 조사되었고 QTL 분석을 위해 one-way ANOVA 테스트를 하였다. 통계분석 결과 두 프라이머(K16-1, L2-2)가 저항성과의 상관관계를 보여 주었으나 유의성은 인정되지 않았다.