Lateral coefficient of friction for characterizing winter road conditions

2016 ◽  
Vol 43 (1) ◽  
pp. 73-83 ◽  
Author(s):  
Sahar Salimi ◽  
Somayeh Nassiri ◽  
Alireza Bayat ◽  
Don Halliday
Keyword(s):  
Field Experiments ◽  
Surface Friction ◽  
Concrete Surface ◽  
Snow Accumulation ◽  
Frictional Heat ◽  
Vehicle Speed ◽  
Test Road ◽  
Winter Road ◽  
Friction Measurements ◽  
The University

Real Time Traction Tool (RT3)-Curve was used in this study to evaluate the effect of ice and snow on tire–road lateral friction coefficient, herein referred to as the Halliday Friction Number (HFN). The field experiments for the study were performed in winter 2012–2013 on the University of Alberta’s test road facility in Edmonton, Alberta. Each run was repeated at three target speeds under varied road conditions, bare dry, dry with ice patches, ice, and three levels of snow accumulation. No considerable correlation was found between vehicle speed and the friction measurements for bare dry, ice- and snow-covered conditions. Expectedly, the bare dry asphalt concrete surface had the highest HFN, the presence of ice reduced the dry surface friction by 55%. The accumulation of snow on the dry surface reduced the HFN further than ice, by 69, 75, and 81% for light, moderate, and heavy snow, respectively. A falling trend was observed for friction as more snow accumulated on the ground. Analysis of the effect of number of truck passes over ice at −3.5 and −5 °C showed that ice can become more slippery after each pass of traffic. A similar analysis for snow revealed that more passes over moderate snow will compact the fresh snow into a slippery surface. For light snow, even at low temperatures (<−10 °C), passes of traffic will melt the snow through frictional heat and result in higher friction values.

Monitoring Pavement Surface Macrotexture and Friction

2015 ◽  
Vol 2525 (1) ◽  
pp. 111-117 ◽  
Author(s):  
Nima Kargah-Ostadi ◽  
Andrew Howard
Keyword(s):  
Surface Friction ◽  
Vehicle Speed ◽  
The Road ◽  
Pavement Surface ◽  
Friction Testing ◽  
Profile Depth ◽  
Friction Measurements ◽  
On The Road ◽  
The Relationship

The amount of available friction and texture depth are primary concerns in the evaluation of pavement surface safety characteristics. The two components of microtexture and macrotexture provide pavement surface friction. Macrotexture properties are collected with laser-based devices at highway speeds, but a proper evaluation of microtexture is available only with stationary devices or laboratory experimental methods. The industry is trying to develop practical methods for monitoring microtexture at the network level. Pertinent quantification for both friction components is valued because the common locked-wheel testing of skid resistance depends on surface temperature, presence of dirt and oil on the road surface, and vehicle speed. This case study examined the relationship between laser-based mean profile depth (MPD) and the friction number (FN) collected with a locked-wheel skid trailer on Louisiana highways. The analysis showed that quantified microtexture data were required in conjunction with the macrotexture to establish a significant correlation with friction measurements. However, the correlation between MPD and FN appeared to be significantly stronger at higher speeds of friction testing. Lower and higher threshold values were determined from the first and third quartiles of MPD and FN data. At speeds of about 50 mph, 71% of the pavement sections with MPD of less than the lower texture threshold also had FN values of less than the lower friction threshold. This lower MPD threshold of 0.036 in. can be implemented in network-level monitoring operations to determine areas of concern that require friction testing.

Variation-Based Transparency Analysis of an Internet-Distributed Hardware-in-the-Loop Simulation Platform for Vehicle Powertrain Systems

2009 ◽  
Author(s):  
Tulga Ersal ◽  
Mark Brudnak ◽  
Jeffrey L. Stein ◽  
Hosam K. Fathy
Keyword(s):  
The Internet ◽  
Vehicle Speed ◽  
Hardware In The Loop ◽  
Engine Torque ◽  
Us Army ◽  
Geographically Dispersed ◽  
Delay Jitter ◽  
Motion Simulator ◽  
Ann Arbor ◽  
The University

Recent work by the authors and colleagues developed an Internet-distributed hardware-in-the-loop simulation (HILS) platform to integrate two geographically-dispersed HILS setups over the Internet, namely, the engine-in-the-loop simulation setup at the University of Michigan (UM) in Ann Arbor, MI, and the driver-in-the-loop ride motion simulator at the US Army Tank-Automotive Research, Development and Engineering Center (TARDEC) in Warren, MI. As the literature discusses in detail, distributing the HILS over the Internet introduces transparency issues due to the delay, jitter, and loss associated with the Internet. This paper first illustrates on a simple example that distributing the simulation can in and of itself be another important source of transparency degradation. Then, the paper presents a variation analysis to evaluate the effect of these two main sources of transparency degradation on the performance of the abovementioned setup. The paper concludes that transparency and how it is affected by distributing the simulation and by the delay, jitter, and loss associated with the Internet is dependent on the signal of interest. Specifically, it is shown that distributing the simulation has more effect on the transparency of the engine torque and throttle signals than the delay, jitter, and loss of the Internet between Ann Arbor and Warren, whereas it does not significantly affect the transparency of vehicle speed unless the Internet delay increases significantly.

The Energy Efficiency Of Willow Biomass Production In Poland – A Comparative Study

2015 ◽  
Vol 22 (1) ◽  
pp. 123-130 ◽  
Author(s):  
Stefan Szczukowski ◽  
Józef Tworkowski ◽  
Mariusz J. Stolarski ◽  
Michał Krzyżaniak
Keyword(s):  
Energy Efficiency ◽  
Comparative Study ◽  
Biomass Production ◽  
Field Experiments ◽  
Energy Gain ◽  
Short Rotation ◽  
Energy Inputs ◽  
The University

Abstract Field experiments with willow (Salix L.) coppice cultivation and Eko-Salix systems have been conducted at the University of Warmia and Mazury since 1992. In that wider context, the aim of the work described here was to compare energy inputs involved in setting up a plantation and producing biomass, and to assess the efficiency of willow-chips production under the coppice and Eko-Salix systems. The energy gain determined in the experiments was several to more than twenty times as great as the inputs needed to operate the plantation and to harvest willow biomass, this leaving both systems of willow cultivation under study attractive where setting up short-rotation coppices is concerned.

Bioethanol Production From High Sugary Corn Genotypes by Decreasing Enzyme Consumption

2019 ◽  
pp. 216-240 ◽  
Author(s):  
Hossain Zabed
Keyword(s):  
Biological Sciences ◽  
Literature Review ◽  
Product Quality ◽  
Ethanol Production ◽  
Comparative Evaluation ◽  
Field Experiments ◽  
Bioethanol Production ◽  
Research Questions ◽  
The University ◽  
Expected Outcomes

This is a PhD proposal defended in a 2012-2013 session at the Institute of Biological Sciences, Faculty of Science, University of Malaya, Malaysia. The proposal has been written in accordance with the requirements of the university under the sub-headings: background, problem statement, rationale, hypothesis and research questions, research objectives, literature review, methodology, scope, expected outcomes and concluding remarks, work schedule, and references. This proposal provides a comprehensive study on bioethanol production from corn. First, it discusses development and field experiments of high sugary genotypes (HSGs). Secondly, it provides a comparative evaluation of enzyme consumptions and ethanol production between normal and HSG corn genotypes. Finally, this proposal provides evaluation of the co-product quality for both groups of genotypes. The readers who are interested to conduct any further study on corn-based bioethanol would be benefited from this proposal.

scholarly journals Field experiments on “living” snow fences

1998 ◽  
Vol 26 ◽  
pp. 217-220 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Pierre Mullenbach
Keyword(s):  
Field Experiments ◽  
Snow Accumulation ◽  
Real Problem ◽  
Effective Height ◽  
Natural Plant ◽  
Drifting Snow ◽  
Snow Fence ◽  
Limited Scale ◽  
Living Fences ◽  
Snow Fences

In Franee, drifting snow is generally controlled using artificial snow fences. Living snow fences are not a new concept but they have only been used on a limited scale. Research directly related to natural plant barriers is limited. We therefore decided to study the behaviour of species that would survive and grow satisfactorily in the French Alps.In the first experiment, we compared the storage capacity of several different kinds of living fences consisting of pruned spruces, unpruned spruces and sorbs.Field observations during the winter of 1995-96 proved that deciduous trees such as sorbs are effective, and that pruning the lower 50 cm is not effective at the end of the season because of the weight of snow on low branches.However, the use of natural plant barriers has disadvantages: a living snow fence takes time to reach an effective height and is difficult to establish on windy sites at a high altitude. This is a real problem. Therefore, in a second experiment, we studied the death rate of larches planted behind a fence. We noticed that the snow fence had several effects, snow accumulation (until the planted trees grew up) and protection of the planted trees.

scholarly journals Image-Based Underwater Inspection System for Abrasion of Stilling Basin Slabs of Dam

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Yonglong Li ◽  
Hua Zhang ◽  
Shuang Wang ◽  
Haoran Wang ◽  
Jialong Li
Keyword(s):  
Field Experiments ◽  
Concrete Surface ◽  
Inspection System ◽  
Underwater Robot ◽  
Stilling Basin ◽  
Underwater Image ◽  
Surface Damages ◽  
Quantitative Analysis Method ◽  
Exposure Ratio ◽  
Periodic Inspections

The abrasion of stilling basin slabs which is caused by waterborne particles is one of the main surface damages in the operation of hydropower station. For determining whether to repair the stilling basin slabs, periodic inspections of erosion condition of stilling basin slabs are required. The practical problem is how to get the underwater image without unwatering and how to analyse the abrasion though the images. This paper developed a novel underwater inspection system named UIS-1 which consists of a customized underwater robot and special quantitative analysis method for this situation. Firstly, the integrated component was designed for the underwater robot that partially removes the siltation and obtains the image of the concrete surface of stilling basin slabs in the desired position. Secondly, the paper proposed an image algorithm to obtain aggregate exposure ratio for quantitative abrasion analysis. This image algorithm used SLIC superpixel and the SVM machine learning method to detect the coarse aggregate exposure automatically. Then, the aggregate exposure ratio was calculated to analyse the degree of abrasion. Finally, the UIS-1 system was evaluated in the field experiments of a dam in Sichuan, China, and its performance was discussed by comparison.

scholarly journals Effect of Gypsum Application Rate, Soil Type, and Soil Calcium on Yield, Grade and Seed Quality of Runner Type Peanut Cultivars

2017 ◽  
Vol 44 (1) ◽  
pp. 13-18 ◽  
Author(s):  
J.A. Arnold III ◽  
J.P. Beasley ◽  
G.H. Harris ◽  
T.L. Grey ◽  
M. Cabrera
Keyword(s):  
Field Experiments ◽  
Seed Quality ◽  
Soil Depth ◽  
Application Rate ◽  
Seed Vigor ◽  
Application Rates ◽  
Peanut Cultivars ◽  
Research And Education ◽  
The University ◽  
Gypsum Application

ABSTRACT Calcium (Ca) availability in the 0 to 8 cm soil depth often limits peanut yield and influences grade in the southeastern United States. Field experiments were conducted in 2012 and 2013 at the University of Georgia's Coastal Plain Experiment Station, Tifton, GA (CPES) and the Southwest Georgia Research and Education Center, Plains, GA (SWREC) to determine large-seeded (Georgia-06G) and medium-seed sized (Georgia Greener) runner-type cultivar response to gypsum application rates of 0, 560, 1120, 1650 kg/ha. Peanut pod yield and grade (TSMK) were significantly different between locations with 7610 and 6540 kg/ha at CPES and SWREC, respectively. However, there were no differences between peanut cultivars or gypsum rates. Standard germination, seed vigor (cold germination), and seed Ca content analysis were also conducted on subsamples from each plot. Average peanut seed germination was 97% across all samples. No differences were observed for standard germination or vigor testing. Differences in locations were observed for yield, TSMK, percent jumbo, percent medium kernels, and seed Ca content. Peanut cultivar and gypsum application rate had effects on seed Ca concentration. Seed Ca concentration levels were 825 and 787 mg/kg for Georgia Greener and Georgia-06G, respectively. Seed Ca content increased as field gypsum application rate increased at both locations.

scholarly journals Water and nitrate movements in an agricultural field with different soil frost depths: field experiments and numerical simulation

2013 ◽  
Vol 54 (62) ◽  
pp. 157-165 ◽  
Author(s):  
Yukiyoshi Iwata ◽  
Tomotsugu Yazaki ◽  
Shinji Suzuki ◽  
Tomoyoshi Hirota
Keyword(s):  
Field Experiments ◽  
Water Movement ◽  
Snow Accumulation ◽  
Control Plot ◽  
Soil Freezing ◽  
Nitrate Content ◽  
Agricultural Field ◽  
Snowmelt Period ◽  
Frost Depth ◽  
Treated Plot

AbstractTo evaluate water and anion movement in an agricultural field in different frost conditions, a paired-plot field experiment was conducted at an agricultural site in northern Japan where a significant decrease in the frost depth has occurred during the past 20 years. Snow cover was removed to enhance soil freezing in one plot (treated plot), whereas natural conditions were maintained in a control plot. The maximum frost depth was 0.43 m in the treated plot and 0.11 m in the control plot, which induced substantial differences in water movement throughout the winter. A substantial amount of water moved upward before the onset of snowmelt. However, nitrate did not move markedly before the snowmelt period in either plot. The amount of snowmelt infiltration in the control plot was larger than in the treated plot. Correspondingly, the peak of nitrate content in the control plot was deeper than that in the treated plot after the snowmelt period. Soil freezing, snow accumulation and snowmelt processes were simulated reasonably well using a one-dimensional numerical model: Simultaneous Heat and Water (SHAW). Nevertheless, the model performed poorly for simulating soil thawing and soil water movement, suggesting a need for improvement.

Irrigated Forage Production under Extreme Arid Zone Conditions in Saudi Arabia

1976 ◽  
Vol 12 (2) ◽  
pp. 177-187 ◽  
Author(s):  
J. Farnworth
Keyword(s):  
Saudi Arabia ◽  
Nutritional Value ◽  
Management Practices ◽  
Field Experiments ◽  
Arid Zone ◽  
Perennial Species ◽  
Forage Production ◽  
North Wales ◽  
High Yields ◽  
The University

SUMMARYSince 1970 the University College of North Wales, in co-operation with the Saudi Arabian Ministry of Agriculture and Water, has been investigating the potential for forage production in all-year-round irrigated conditions in Saudi Arabia, and the principal results of the first 4 years of field experiments are discussed. Both temperate and tropical annual forages as well as perennial species were tested, and generally produced high yields with high nutritional value. Fertilizer responses and different management practices were evaluated and their relevance to the development of systems of forage production are discussed.

Influence of pavement surface noise: the Korea Highway Corporation test road

2007 ◽  
Vol 34 (7) ◽  
pp. 809-816 ◽  
Author(s):  
Sungho Mun ◽  
Dae Seung Cho ◽  
Tae Muk Choi
Keyword(s):  
Road Traffic ◽  
Traffic Noise ◽  
Road Traffic Noise ◽  
Noise Power ◽  
Vehicle Speed ◽  
Urban Centers ◽  
Pavement Surface ◽  
Environmental Impact Assessments ◽  
Test Road ◽  
System Issue

Because of a significant increase in the number of vehicles using national highway networks that link major urban centers, road traffic noise—with its harmful impact on the environment—has become a major pavement system issue. Therefore, it is necessary to assess the characteristics of different types of pavement and their influence on road traffic noise. The Korea Highway Corporation test road, with eight different pavement surfaces, was used to test and analyze noise from tire–pavement interaction and from vehicle power trains. Noise was measured in a novel test approach using a surface microphone. The results show that traffic noise levels vary widely according to pavement surface type, vehicle type, and vehicle speed. The findings of this investigation can be used to determine appropriate pavement surfaces that will satisfy specific environmental impact assessments for given traffic conditions and requirements.Key words: road traffic noise, tire–pavement noise, power-train noise, surface microphone.

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