• 한국도로학회논문집
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• 제15권4호
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• pp.95-105
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• 2013

PURPOSES: The purpose of this study is to research the influence of road traffic noise by road slope through the analysis of the field road traffic noise and determine consideration of road slope in the case of appling active noise cancellation. METHODS: This study measures vehicle's noise by the NCPX method at the three field sections such as uphill, downhill, and flatland. Total sound pressure and sound pressure level by the 1/3 octave band frequency are calculated through the raw field data. Total sound pressure level is compared by ANOVA test and T test statistically. The results obtained are compared in accordance with the road slope and the progress of the uphill section. RESULTS : The noise characteristic of early, medium, and last parts of uphill was found to be consistent when the vehicle was travelling uphill section. The result of statistical test, it was shown that total sound pressures are not different each other. According to the comparison by the geometry, sound pressure of the uphill section was higher than those of the flatland and downhill section in high frequency band. By the result of statistical test, total sound pressure are different according to geometry in the case of high vehicle speed. In the comparison result by road slope, each sound pressure level was found to be consistent in total frequency. However, total sound pressure proportionally increased according to road slope. CONCLUSIONS: It is found that the effect of road slope on noise generation was little in this experimental sites.

• 한국자동차공학회논문집
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• 제6권1호
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• pp.73-79
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• 1998

For the design and development of the wheel type excavator, the dynamic effects of travelling on the performance of the equipment should be first analyzed and conside- red in the initial design stage. In order to test the durability of the equipment in a short period, th travelling test should be performed over accelerated durability test tracks. which is more severe than general field roads such as city road, paved road, unpaved road and rough road. In this paper, a parametric study is performed in order to determine important design parameters of durability test track of a wheel type excavator. A rigid body model is developed using DADS and dynamic analysis is performed for the equipment travelling over several test roads with different severity. A comparison of test and analysis results is also presented.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.603-606
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• 2000

The cost needed for the construction and management of highways in the whole nation is rapidly growing so the research that can decrease the cost is required. However, most of the highway specs have simply converted from those of other countries, including USA. Therefore, some of our design and construction specs were not the optimum ones based on our own situation, requiring a research under the actual traffic and environment of our nation. The use of test road develops many aspects of highway engineering. Those are evaluation of construction materials, a general overview of korea pavement design and serviceability under the actual traffic and environmental condition of the nation. It is also economical and efficient compared to the trial construction of each item in spreaded form. A test road, 7.7km long with two lanes, is being constructed on the Inner Central Expressway. In this test road, 2.7km is planned for asphalt pavement and 3.4km is planned for concrete pavement. Three test bridges and five earth retaining structures will be included in the test road. Based on the master plan, the major performance was progressing such as detailed research modules of each area, preliminary research for the future research, sensor surveys for the behavior analyses of pavements and structures with installation methods and data acquisition systems, the foundation research of Integrated Instrumentation System and the Management Plan for automated measurement. Some area(structure research division, geotechnical research division) was designed the instrumentation plan because some instrument sensors must be installed during the construction of the test road. And then the instrumentation plan of each area was enforcing because a large majority of the instrument sensors must be installed after the construction of the test road. The field surveys with material property tests and pilot instrumentation test with sensor tests was also performing in accordance with the construction in the field.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.462-465
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• 2014

It is well known that tire/road factors have a large influence on overall tire performance. In this paper, the basic study on the effects of tire/road factors on the pass-by noise performance of tire labeling has been carried out through experimental tests. The tire pass-by noise is affected by road characteristic factors, especially greatly influenced by road friction coefficient, and the next dominant factor is road chipping size. For several authorized pass-by noise test tracks, the pass-by noise correlation test has been done to know the test site effect, which results in 2~3dB(A) variation of pass-by noise level. Finally, it is shown that the winter tire is differently influenced by the pass-by noise test track characteristics, as compared to all-season tire and summer tire.

• 한국소음진동공학회논문집
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• 제13권5호
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• pp.327-333
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• 2003

Several tests are performed to evaluate road booming noise. Baseline test delivers the information of road noise characteristics. Coupling effect between structure and acoustics is obtained from the mode shapes and the natural frequencies by the modal test. Equivalent stiffness at joint areas between chassis and car-body system can be determined by the input point inertance test. Noise sensitivity of body mounting point of a chassis part can be obtained from the noise transfer function test with input point inertance test. Operational deflection shape makes us analyze the actual vibration modes of the chassis system under actual leading and find noise sources very easily. Finally, the transfer path analysis is used to Identify noise Paths through the chassis system. The objectives and the procedures of the tests are described in this Paper Also, the guideline for efficient road noise evaluation test can be found.

• 융복합기술연구소 논문집
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• 제4권2호
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• pp.67-70
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• 2014

Recently EU has been recognized that there is a difference of emission quantity between emission certification test mode and real-road driving test. Accordingly the European Commission is currently preparing to require real-road testing as part of the passenger car type-approval process in the EU. vehicle manufacturers from 2017 are expected to test new vehicles not only under laboratory conditions but also on the real-road, using PEMS equipment. Therefore the purpose of this study is to analyze the emission and Fuel Economy of CVS-75 mode test using chassis dynamometer and RDE test using PEMS equipment by PHEV passenger car.

• 한국자동차공학회논문집
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• 제10권5호
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• pp.190-198
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• 2002

Full scale durability test in the laboratory is an essential of any fatigue life evaluation of components or structures of the automotive vehicle. Component testing is particularly important in today's highly competitive industries where the design to reduce weight and production costs must be balanced with the necessity to avoid expensive service failure. Generally, hydraulic road simulator is used to carry out the fatigue test and the vibration test. In this paper, the algorithm and software to realize the real road profile are developed. The operation software for simultaneously controlled multi-axial road simulator is developed and the input and output data are displayed window based PC controller in the real time. Futhermore, the software to generate the real road profile are developed. The validity of the software are verified by applying the belgian road, the city road, the highway, and the gravel road. The results of the above experiment show that the real road profiles are realized well after 10th iteration.

• 한국산업융합학회 논문집
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• 제17권1호
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• pp.7-14
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• 2014

In this study, characteristic of elastic paving materials in bicycle road using polyurethane were studied experimentally. As a results, following their good result was obtained. Bicycle road packaging materials are flexural strength g test, ratio of mass change after freezing and thawing, repulsion elasticity test, water Permeation coefficient test and slip resistance test results showed good performance.

• 한국군사과학기술학회지
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• 제20권2호
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• pp.231-237
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• 2017

The profile of unpaved road is an important issue in the reliability of endurance test. Efforts on measuring 2D road profile and analyzing the severity have been continued in the study of performing reliable endurance test evaluations through reflecting the results of such measurement and analysis. However, 2D road profile has limitation in measuring the profile in the road width direction because data is obtained along the trailer wheel track. Therefore, in order to measure 3-dimensional shape of road surface and construct severity DB of 3D road profile, Changwon Proving Ground(CPG) of Agency for Defense Development(ADD) developed 3D profilometer which is composed of laser scanner, IMU, GPS, encoder and so on. This paper focuses on the analysis of unpaved road severity using 3D road profile for army operation roads. This results will be used to manage test courses severity of CPG.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.980-985
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• 2002

Several tests are performed to evaluate road booming noise. Baseline test delivers the information of road noise characteristics. Coupling effect between structure and acoustics is obtained from the mode shapes and the natural frequencies by the modal test. Equivalent stiffness at joint areas between chassis and car-body system can be determined by the input point inertance test. Noise sensitivity of body mounting point of a chassis part can be obtained from the noise transfer function test with input point inertance test. Operational deflection shape makes us analyze the actual vibration modes of the chassis system under actual loading and find noise sources very easily. finally, the transfer function analysis is used to identify noise paths through the chassis system. However, all of the tests above mentioned must be performed to evaluate road booming noise. The objectives and the procedures of the tests are described in this paper. Also, the guideline for efficient road noise evaluation test can be found.