407 results on '"Gravel road"'
Search Results
2. Predicting the roadway width of forest roads by means of airborne laser scanning
- Author
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Tomi Karjalainen, Ville Karjalainen, Katalin Waga, and Timo Tokola
- Subjects
LiDAR ,Gravel road ,Trafficability ,Bearing capacity ,Road width ,Physical geography ,GB3-5030 ,Environmental sciences ,GE1-350 - Abstract
Modern forestry relies on an extensive network of well-maintained forest roads. However, the trafficability of forest roads can be limited by poor construction or by insufficient load-bearing capacity caused by, for example, weather conditions. In all forestry operations, the forest roads should be able to support heavy vehicles during the transport of roundwood and harvesting machinery, so logistics must be carefully planned to ensure good road trafficability. To facilitate this planning, it is necessary to know the various characteristics of the forest road in terms of its width, structure and load-bearing capacity. Obtaining such information using remote sensing data would be beneficial. In this study, we used airborne laser scanning (ALS) data to assess the width of the roadway on forest roads. We developed several algorithms that were used to assess roadway width based on the cross-sectional data (derived with ALS) of the roads in 8-m long segments. The ALS echoes within the segments were classified into 20 cm wide strips which the algorithms then analyzed in a stepwise manner. Both height and intensity information from the ALS data were utilized. The algorithm results were then used as predictors in linear models to predict the roadway width. The main focus was on the road level, i.e., aggregated values from 25 different roads were used in model fitting. In terms of root mean square error (RMSE) values, accuracies of approximately 20–30 cm (or 7–10 %) were obtained for the predicted roadway widths with a separate validation data. This level of accuracy can be considered adequate given the characteristics of the ALS data used in the modelling. The results indicate that the presented approach has potential for practical applications to predict the width attributes of forest roads.
- Published
- 2024
- Full Text
- View/download PDF
3. Design of Geotextile Reinforced Gravel Roads Using Giroud and Han Approach for Indian Condition.
- Author
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Dheiveekan, Jayalakshmi and Bhosale, S.S.
- Subjects
GRAVEL ,ROAD construction ,ROADS ,AIR pollution ,ROAD maintenance ,TRANSPORTATION costs - Abstract
Sustainable pavement is the need of the hour using the mechanistic and robust pavement design approach, eliminating empiricism in the present IRC SP 72-2015 design guidelines, if any. Giroud and Han (2004) (GH) approach has confirmed existing empiricism in IRC SP 72-2015 design guidelines and permits the use of locally available material, thus saving transportation costs and reducing air pollution. IRC SP 72 – 2015 recommends design thickness only for the unreinforced condition in gravel roads for the maximum rut of 50mm. This paper presents the comparative study of an unreinforced and geotextile-reinforced gravel road design for Indian conditions with the rut as a vital design parameter using the GH method for subgrade classes with 2% to 5% CBR and the maximum traffic count of 100,000. The proposed unique equation provides Allowable Rut Depth (ARD) based aggregate thickness for 10,000 to 100,000 traffic count apart from simplifying the complex procedure of the GH approach for IRC SP 72-2015 data. The unique equation's result reveals an increase of 22.65% in aggregate thickness is attributed to the increase in ARD of 30mm using locally available poor aggregates. This confirms the practical relevance of ARD in pavement design that may help in planning maintenance programs and road rehabilitation strategies. The results obtained from the unique equation match 85 to 100% with GH results. Saving up to 36.5% to 76.9% of costly aggregate is found in the case of geotextile-reinforced gravel roads in Indian conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Runoff response and sediment yield from urban road surfaces: an experimental study in semi-arid northern Ethiopia.
- Author
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Hagos, Araya, Grum, Berhane, Gebru, Fiseha, Yemane, Shishay, Berhane, Solomon, Berhe, Melaku, Tekleyohannes, Sesen, Abera, Tesfahunegn, Aregawi, Ashenafi, and Abebe, Bizuneh A.
- Subjects
- *
PAVEMENTS , *RUNOFF , *SEDIMENTS , *FIELD research , *GRAVEL - Abstract
This study investigated the effect of gravel and cobblestone road surfaces on runoff responses and sediment yield in semi-arid northern Ethiopia. A field experiment was set up with six treatments of gravel and cobblestone road surfaces at 1, 3 and 7% slope gradients. Cobblestone road surface produced significantly lower runoff than gravel. Slope gradient had a significant effect on the runoff amount from gravel and cobblestone road surfaces. Runoff reductions by cobblestone road surface compared to gravel at 1, 3 and 7% slopes were 27, 30 and 31%, respectively. Runoff coefficients for gravel road surface at 1, 3, and 7% slopes were 0.60, 0.65 and 0.68, respectively. Runoff coefficients for cobblestone at 1, 3 and 7% slopes were 0.41, 0.45 and 0.47, respectively. Slope gradient had a significant effect on sediment yield for a gravel road surface. Sediment yield from cobblestone, however, was insignificant compared to gravel. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. رفتارسنجی وضعیت آبگذرها و رویه جاده جنگلی غیرآسفالته در شرایط ترافیک مختلف.
- Author
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یداهلل رسولی آکر, مجید لطفعلیان, آیدین پارساخو, مهران نصیری, and حسن اکبری
- Abstract
Background and Objectives: The construction of a forest road disturbs the natural balance of water flow in the forest area. This balance can be maintained to a large extent by installing culverts and building side channels in different traffic routes. Culverts or drainage structures, as well as the road surface, often reflect anomalies caused by varying traffic intensities on the road surface. These enable a road manager to determine the severity of destruction and timely protection. Materials and Methods: In this study, the static and dynamic anomalies of culverts and surface of forest roads at different traffic levels were investigated in district #1 of Reyhanabad and Pajim of Al-Ghadir Khalil Shahr forestry plans. First, specifications of all culverts (pipe or concrete) including thickness, diameter, length, depth, culvert installation slope and angle, road slope and flow rate of the culvert were measured using a clinometer and tape meter. The discharge rate was calculated by measuring the flow cross-section and flow velocity as a function of hydraulic radius, Manning's coefficient and flow slope. In the section of static anomalies, the health level of culvert in 4 classes and the condition index of unpaved roads (UPCI-unpaved road condition index) were measured. The dynamic anomaly includes the amount of culvert vibration during vehicle passages was calculated using a vibrometer. Results: The results showed that with increasing culvert installation depth and traffic levels, the numerical value of UPCI decreased. The lowest UPCI values were recorded on slopes <5%. Culvert health increased with increasing installation angle. The lowest values of culvert health were measured on slopes < 5%. In general, the lowest level of vibration was measured in the case of unarmored culverts that were installed at a depth of 50-100 cm, with a slope of 5-8% and an angle of 100-120 degrees on road with low traffic. In routes with a traffic intensity of > 4 vehicles per day, the culvert vibration level was estimated at 2.24 Richter while it is estimated at 1.99 Richter on routes with an intensity of < 4 vehicles per day. The culvert reinforcement and depth had a positive effect on the culvert vibration level. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
6. Influence of in situ oilsands development on occurrence of an avian peatland generalist and specialist.
- Author
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Carpenter, Thea M., Mahon, C. Lisa, Bayne, Erin, Keim, J. L., and Nielsen, Scott E.
- Abstract
Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
- Full Text
- View/download PDF
7. Guidelines for the Selection, Specification, and Application of Chemical Dust Control and Stabilization Treatments on Unpaved Roads
- Author
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Jones, D.
- Subjects
Unpaved road ,gravel road ,unsealed road ,fines preservation ,dust control ,stabilization ,unpaved road management - Abstract
Unacceptable levels of dust, poor riding quality, impassability in wet weather, and unsustainable maintenance and gravel replacement practices are experienced on most unpaved road networks, and although it is acknowledged that unpaved roads are fundamental to local, regional, and national economies, many current management practices used on these roads leave much to be desired. Over the past 100 years a range of chemical treatments has been developed to fill the need for reducing the environmental and social impacts of road dust, improving the performance and safety of unpaved roads, and/or improving the properties of marginal materials to the extent that a road can be given all-weather status or upgraded to a paved standard. Most of these chemical treatments are proprietary and there is often little documented information regarding the chemistry of the treatment, the results of experimental trials to determine under what conditions the chemical treatment will work best, or guidelines on where and how to use the treatment. Most unpaved road chemical treatments carry no formal specification nor do they adhere to formal environmental testing requirements. Consequently, there has been no large-scale effort to establish and/or implement formal unpaved road chemical treatment programs anywhere in the world, other than those used in site-specific industrial applications such as mining operations. This guide introduces a new process for selecting an appropriate chemical treatment category for a specific set of unpaved road conditions using ranked potential performance. The process is based on the practitioner setting an objective for initiating a chemical treatment program and understanding the road in terms of materials, traffic, climate, and geometry. Using the information collected, the most appropriate chemical treatment subcategories for a given situation can be selected from a series of charts and ranked using a simple equation. This process can be completed manually using a paper form, or by using a web-based (www.ucprc.ucdavis.edu) or spreadsheet tool. Matrices for each of the objectives were developed based on documented field experiments and the experience of a panel of practitioners. Guidance on specification language for procuring and applying unpaved road chemical treatments is also provided, along with comprehensive guidance on understanding unpaved road wearing course material performance.
- Published
- 2017
8. Influence of in situ oilsands development on occurrence of an avian peatland generalist and specialist
- Author
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Thea M. Carpenter, C. Lisa Mahon, Erin Bayne, J. L. Keim, and Scott E. Nielsen
- Subjects
gravel road ,in situ ,junco hyemalis ,oil sands development ,peatland ,setophaga palmarum ,songbird occurrence ,Ecology ,QH540-549.5 - Abstract
Demand for petroleum products is causing habitat loss, alteration, and fragmentation of boreal forests in western Canada. Associated exploratory and extraction activities from in situ oil sands leave a network of (1) permanent polygonal features (e.g., processing facilities, extraction sites, gravel pits); (2) permanent linear features (e.g., roads, pipelines); (3) temporary polygonal features (e.g., exploratory well sites); and (4) temporary linear features, (e.g., winter roads, seismic lines). We examined the impact of these different types of disturbances on the occurrence of a generalist, the Dark-eyed Junco (Junco hyemalis) and a peatland specialist, the Palm Warbler (Setophaga palmarum) for an in situ development-lease area in northeast Alberta, Canada. Our goal was, first, to determine if energy development features have positive, negative, or neutral effects on species occurrence, beyond the amount of habitat disturbed, and second, to identify the relative impact of different types of energy features. Permanent polygonal features negatively influenced both species, decreasing the odds of occurrence for Dark-eyed Juncos by 0.63 times and 0.44 times for Palm Warblers for every 10% increase in percent area. However, permanent linear features increased odds of occurrence for Dark-eyed Juncos by 1.73 times and Palm Warblers by 3.93 times. We speculate that permanent linear features increase vegetation heterogeneity or influence insect-prey availability through edge effects. Although permanent polygonal and linear features had opposite effects (negative and positive, respectively), they had a similar relative effect on occurrence for both species. There were no effects of temporary polygonal or linear features on occurrence for either species examined here. Whereas our understanding of birds in boreal peatland forests is limited, these results are consistent with studies that suggest permanent linear features have more substantive local scale impacts than temporary disturbances.
- Published
- 2022
9. AN ANALYSIS OF VIBRATION FOR A GASOLINE-ENGINE CAR DRIVING ON THREE TYPES OF ROADS.
- Author
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Suphattharachai Chomphan
- Subjects
FAST Fourier transforms ,AUTOMOBILE driving ,POSITION sensors ,SENSOR placement - Abstract
An analysis of vibration signals has been proposed for a personal gasoline-engine car while driving on three types of roads including paved road, concrete road, and gravel road. The wired sensors are placed upon three positions inside the passenger room: right-front seat surface, left-front seat surface, and rear seat surface. The objectives of this analysis are to differentiate the corresponding vibration reflecting from driving upon three types of roads and to differentiate the vibration at three different positions of sensors inside the passenger room. The signal analysis technique of Fast Fourier Transform is utilized in this analysis, the obtained spectrum is investigated to extract the dominant peaks. Thereafter, the averages of the peak values are calculated for six different engine speeds ranging from 0-30 km/h. These averaging calculations are based on 50 five-second-length samples of vibration signals. To achieve the first objective, the experimental results insist that the highest peak values are mostly of the gravel road, meanwhile, the lowest peak values are of the paved road. To accomplish the second objective, the experimental results strongly confirm the following comparisons. In the case of paved road, the highest peak values are at the rear seat surface, meanwhile, in the case of concrete road, the highest peak values are at the left-front seat surface. Finally, in the case of gravel road, the highest peak values are at the rear seat surface. In conclusion, this study confirmed that the proposed approach can be used to differentiate the signal features of all scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
10. Automation of forest road inventory using computer vision and machine learning
- Author
-
de Flon, Jacques and de Flon, Jacques
- Abstract
There are around 300, 000 kilometer of gravel roads throughout the Swedish countryside, used every day by common people and companies. These roads face constant wear due to harsh weather as well as from heavy traffic, and thus, regular maintenance is required to keep up the road standard. A cost effective maintenance requires knowledge of where support is needed and such data is obtained through inventorying. Today, the road inventory is done primarily by hand using manual tools and requiring trained personel. With new tools, this work could be partially automated which could save on cost as well as open up for more complex analysis. This project aims to investigate the possibility of automating road inventory using computer vision and machine learning. Previous works within the field show promising results using deep convolutional networks to detect and classify road anomalies like potholes and cracks on paved roads. With their results in mind, we try to translate the solutions to also work on unpaved forest roads. During the project, we have collected our own dataset containing 3522 labelled images of gravel and forest roads. There are 203 instances of potholes, 614 bare roads and 3099 snow covered roads. These images were used to train an image segmentation model based on the YOLOv8 architecture for 30 epochs. Using transfer learning we took advantage of pretrained weights gained from training on the COCO dataset. The predicted road segmentation results were also used to estimate the width of the road, using the pinhole camera model and inverse projective geometry. The segmentation model reaches a AP50−95 = 0.746 for the road and 0.813 for the snow covered road. The model shows poor detection of potholes with AP50−95 = 0.048. Using the road segmentations to estimate the road width shows that the model can estimate road width with a mean average error of 0.24 m. The results from this project shows that there are already areas where machine learning could assist hu
- Published
- 2023
11. On the establishment of a data-driven approach to gravel road maintenance
- Author
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Mbiyana, Keegan and Mbiyana, Keegan
- Abstract
Gravel roads are essential for economic development as they facilitate the movement of people, transportation of goods and services, and promote cultural and social development. They typically connect sparsely populated rural areas to urban centres, providing essential access for residents and entrepreneurs. Maintaining these roads to an acceptable level of service is crucial for the efficient and safe transportation of goods and services. However, substantial maintenance investmentis required, yet resources are limited. Gravel roads are prone to dust, potholes, corrugations, rutting and loose gravel. They deteriorate faster than paved roads, and their failure development is affected by traffic action and physical, geometric and climatic factors. Thus, more condition monitoring and proper road condition assessment are necessary for dynamic maintenance planning to reach efficiency and effectiveness using objective, data-driven condition assessment methods to ensure all-year-round access. However, objective data-driven methods (DDMs) are not frequently used for gravel road condition assessment, and where they have been applied, the practical implementation is limited. Instead, visual windshield assessment and manual methods are predominant. Visual assessments are unreliable and susceptible to human judgement errors, while manual methods are time-consuming and labour-intensive. Maintenance activities are predetermined despite dynamic maintenance needs, and the planning is based on historical failure data rather than the actual road condition. This thesis establishes a data-driven approach to gravel road maintenance describing the systematic assessment of the gravel road condition and collection of the condition data to ensure efficient and effective maintenance planning. This thesis uses a design research methodology based on a literature review, concept development, interview study and field experiments. A holistic approach is proposed for data-driven maintenance of g, Sustainable maintenance of gravel road
- Published
- 2023
- Full Text
- View/download PDF
12. Grizzly bears, impact significance, and the Greenville to Kincolith road project in West-Central British Colombia
- Author
-
Demarchi, Mike W.
- Subjects
British Columbia ,gravel road ,bears ,road impact - Abstract
A project to link the communities of Greenville and Kincolith, British Columbia, with an all-season gravel road was initiated in the mid 1990s. Construction is expected to run from 2001 through 2003. This was the first access project in British Columbia to be reviewed by provincial and federal environmental assessment authorities. A framework for determining the “significance” of environmental effects was developed to examine the spatial extent, magnitude, and duration of adverse effects. The project was expected to have significant direct and indirect residual impacts on grizzly bears, as a considerable amount of high-quality habitat would be lost or alienated and there would be a high risk of bear mortality due to increased human-bear interactions. Faced with the costly, but legislated requirement that all significant effects undergo panel review, approaches to further mitigate residual impacts were sought. The result was an extensive program of bear-human conflict avoidance, enforcement, and a ten-year monitoring program for the project area that would gauge the success of the mitigation plan. Monitoring will document grizzly bear sightings, monitor key habitats, collect hair for DNA analysis to determine minimum numbers of grizzly bears present each year and to develop a database of individuals and parentage, and document problem bear occurrences and grizzly bear mortalities.
- Published
- 2001
13. Economics of upgrading gravel roads to Otta seal surface.
- Author
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Nahvi, Ali, Zhang, Yang, Arabzadeh, Ali, Gushgari, Sharif Y., Ceylan, Halil, Jahren, Charles T., Gransberg, Douglas D., and Kim, Sunghwan
- Subjects
MONTE Carlo method ,GRAVEL ,RURAL roads ,SURFACE preparation ,ROAD users ,COST analysis - Abstract
Maintenance of low volume roads especially gravel roads is costly, and millions of funding annually are spent for aggregate replacement alone. Otta seal, compared to other bituminous surface treatments (BSTs) for low volume roads that require high-quality materials and specialized expertise, can be constructed using cheaper local aggregates and accessible equipment. However, only three states have reported Otta seal constructions and performance in the US. In this study, an economic analysis was conducted to compare the cost of maintaining a gravel road to the cost of upgrading an existing gravel road to a double Otta seal surface. This analysis was conducted at three levels: deterministic life-cycle cost analysis (LCCA), a stochastic Monte Carlo simulation-based LCCA, and a traffic based economic analysis. A generic one-mile rural road in Midwest was considered as a case study location. Although, according to the analysis conducted in this paper, an upgrade to Otta seal investment might be justified by maintenance savings, resorting to only such justification cannot warrant investment in most cases. The upgrade from gravel road to Otta seal, or any other BSTs, might be justified in terms of enhancing safety for road users and also encouraging economic development beneficial to local areas. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
14. 越野车轮胎卵石路面牵引性能有限元与离散元耦合 仿真及试验验证.
- Author
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徐卫潘, 曾海洋, 蒋超, 寇西征, and 臧孟炎
- Subjects
- *
DISCRETE element method , *FINITE element method , *PERFORMANCE of tires , *SOIL testing , *MOTOR vehicle tires , *GRAVEL , *OFF-road vehicles - Abstract
The research on the interaction between off-road tires and soft ground is of great significance to improve the travel performance of off-road vehicle on soft ground. The interaction between tire and soft ground can not be described by the finite element method or the discrete element method effectively. A FEM-DEM model in which the off-road tire is modeled by the finite elements and the gravel road is modeled by the discrete elements was established based on the indoor single wheel soil bin test. The proposed model can be used to accurately describe the complex mechanical properties of off-road tire and the granular features of gravel road. The tractive performance of off-road tire on gravel road at different slip rates is simulated by using the combined finite element-discrete element method in LS-DYNA. The tractive performance parameters of off-road tire, such as tire tractive force and rim sinkage, at different slip rates were obtained and investigated. The numerically simulated results are basically corresponded with the experimental results, which verifies the validity of the combined finite element and discrete element method in studying the interaction between tire and soft ground. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
15. Development of Proving Ground Field Test for Establishment of Vehicle Accelerated Corrosion Test Procedure in Malaysia.
- Author
-
Anuar, L., Amrin, A., Mohamad, R., Aziz, S. A., and Toozandehjani, M.
- Subjects
ACCELERATED life testing ,TESTING - Abstract
This paper presents the field tests conducted as part of activity to establish the vehicle accelerated corrosion test procedure in Malaysia, initiated by the national car manufacturer company, PROTON, Malaysia. Vehicle accelerated corrosion test is a combination of corrosion exposures and durability cycles to accelerate the corrosion process and detect potential failures that may occur during in-service conditions. PROTON conducts the vehicle accelerated corrosion test at external test centres in overseas. However, due to the different climatic of test location, some of the corrosion problems were found to be varied and many did not address the actual corrosion problems detected in Malaysia markets. Hence, the primary aim of this study is to establish a suitable corrosion driving procedure to accommodate the hot and humid environment using facilities in PROTON Test Track. Three corrosion driving procedures were designed based on the number of corrosion exposures and designated as Field Tests 1, 2 and 3. Analysis ruled out that Field Test 3 provides moderate corrosion rate of 0.077-0.842 mm/year and potentially to be the best suited for accelerated corrosion test procedure in Malaysia due to its close replication of actual cosmetic corrosion behaviour observed in Malaysia. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
16. Automatisering av skogsvägsinventering med hjälp av datorseende och maskininlärning
- Author
-
de Flon, Jacques
- Subjects
Machine Learning ,gravel road ,Datorseende och robotik (autonoma system) ,pothole ,forestry ,Computer vision ,Image recognition ,road inventory ,Computer Vision and Robotics (Autonomous Systems) - Abstract
There are around 300, 000 kilometer of gravel roads throughout the Swedish countryside, used every day by common people and companies. These roads face constant wear due to harsh weather as well as from heavy traffic, and thus, regular maintenance is required to keep up the road standard. A cost effective maintenance requires knowledge of where support is needed and such data is obtained through inventorying. Today, the road inventory is done primarily by hand using manual tools and requiring trained personel. With new tools, this work could be partially automated which could save on cost as well as open up for more complex analysis. This project aims to investigate the possibility of automating road inventory using computer vision and machine learning. Previous works within the field show promising results using deep convolutional networks to detect and classify road anomalies like potholes and cracks on paved roads. With their results in mind, we try to translate the solutions to also work on unpaved forest roads. During the project, we have collected our own dataset containing 3522 labelled images of gravel and forest roads. There are 203 instances of potholes, 614 bare roads and 3099 snow covered roads. These images were used to train an image segmentation model based on the YOLOv8 architecture for 30 epochs. Using transfer learning we took advantage of pretrained weights gained from training on the COCO dataset. The predicted road segmentation results were also used to estimate the width of the road, using the pinhole camera model and inverse projective geometry. The segmentation model reaches a AP50−95 = 0.746 for the road and 0.813 for the snow covered road. The model shows poor detection of potholes with AP50−95 = 0.048. Using the road segmentations to estimate the road width shows that the model can estimate road width with a mean average error of 0.24 m. The results from this project shows that there are already areas where machine learning could assist human operators with inventory work. Even difficult tasks, like estimating the road width of partially covered roads, can be solved with computer vision and machine learning.
- Published
- 2023
17. ASSESSMENTS OF THE GRAVEL ROAD DETERIORATION HAVING OF MAINTENANCE CASE STUDY IN JIMMA ZONE
- Author
-
Tarekegn Reta Mesfin and Eba Kitata Kenea
- Subjects
gravel road ,Hydrology ,Gravel road ,surface materials ,TJ1-1570 ,Environmental science ,Electrical engineering. Electronics. Nuclear engineering ,Mechanical engineering and machinery ,deterioration ,maintenance delays ,TK1-9971 - Abstract
Gravel roads deterioration having absence of maintenance is one of the serious issue and common problem in the world. In order to achieve the objectives of the study, the researchers were used questioner survey. To achieve this, first identified the road sections those having lack of maintenance on time existed in the study area. Then the representative road (Sarbo-Busa, Saka-Ushane and Buxure-Sanxama) and questioner surveys samples have been selected by non-probabilistic purposive and systematic sampling respectively. The questioner’s survey was focused on identifying the causes of absence of maintenance and pre-conditions considered. Questioner survey was analyzed by RII. The absence of maintenance was occurred due to lack of budget fund, poor management, lack of skilled manpower, lack of good material quality, lack of regular inspections, poor working environments. The pre-conditions considered while maintaining the gravel roads are: Cost of maintenance, class as the road, maintenance schedule, skilled manpower, topography, number of road users, traffic volume, and economic standards of the society and location of the road from the center. In Jimma zone the deteriorations of gravel roads has been increasing with the absence of maintenance time.
- Published
- 2021
- Full Text
- View/download PDF
18. A Developed Methodology for Determining Gravel Roads’ Level of Service: A Case Study of Wyoming
- Author
-
Khaled Ksaibati, Omar Albatayneh, Dima Husein, and Ahmed Farid
- Subjects
050210 logistics & transportation ,Geographic information system ,Computer science ,Level of service ,business.industry ,05 social sciences ,0211 other engineering and technologies ,Decision tree ,Shapefile ,02 engineering and technology ,computer.file_format ,Track (rail transport) ,Transport engineering ,Highway Capacity Manual ,Mechanics of Materials ,Gravel road ,021105 building & construction ,0502 economics and business ,business ,computer ,Civil and Structural Engineering - Abstract
The focus of this research is to develop a systematic method for ascertaining the level of service (LOS) of gravel roads in the US. To date, such a method does not exist in the highway capacity manual (HCM). In this research, a methodology comprising eight criteria that affect gravel road traffic operations is developed. For each criterion, a rating is assigned. It is either “Good”, “Fair” or “Poor”. The results of each individual criterion rating are combined to develop an overall LOS rating. Furthermore, a non-parametric machine learning technique, namely the classification and regression tree (CART) modeling structure, is employed to quantify the contribution of each criterion to the overall gravel roads’ LOS. As a case study, the developed methodology is implemented to assess traffic operations of gravel roads in Laramie County, Wyoming. The studied gravel road network is compiled and managed in a Geographic information system (GIS) shapefile prepared for the purpose of this research. That is to provide decision-makers in local agencies a computerized tool to efficiently track the performance of their gravel road network. Roughly 63.5% of the gravel road segments are operating at an LOS “Fair”, while 19% are operating at an LOS “Poor” and unexpectedly 17.5% are operating at an LOS “Good”. All gravel roads assessed are low-volume roads with 400 vpd or less. The developed methodology is intended to benefit traffic engineers, decision-makers, and any other stakeholders. The gravel road LOS methodology was developed and applied to Wyoming’s conditions. Minor adjustments might be needed for implementation in other jurisdictions.
- Published
- 2021
- Full Text
- View/download PDF
19. Road Surface State Recognition Based on Semantic Segmentation
- Author
-
Yu Yuan, Li-rong Yan, Zhi-hong Wang, and Wang Shaobo
- Subjects
Identification (information) ,Robustness (computer science) ,Computer science ,Machine vision ,Road surface ,Gravel road ,Segmentation ,Data mining ,computer.software_genre ,computer ,Reliability (statistics) ,Network model - Abstract
In extreme bad weather conditions, vehicles can timely adjust the speed and distance according to the road information, which will effectively reduce the occurrence of traffic accidents. Road type and road adhesion coefficient are the main factors affecting road condition. The traditional identification method of road adhesion coefficient has the characteristics of high cost and low reliability. At the same time, the road surface information recognition technology based on machine vision has become a hot spot in the current research, but the low accuracy and poor robustness are always the difficulties in the research. Based on the semantic segmentation model which is popular in machine vision, a new pavement type recognition technology is proposed by improving the model output network. According to the existing literature, vehicle road surface can be divided into the following 9 categories, including wet asphalt road, dry asphalt road, wet concrete road, dry concrete road, wet soil road, dry soil road, gravel road, compacting snow road and icy road. The standard data set is made by collecting road pictures through taking photos, downloading and other ways, and the pre-processed data set is used to train the improved semantic segmentation network model. Through many tests, training parameters that achieve the desired effect are selected for model parameter solidification, and the semantic segmentation model after solidification is used to predict the road image acquired by the camera. According to the prediction results of the model, the categories of the current driving road surface are obtained. The test results of a large number of road images show that the average classification accuracy of the nine road types is about 94%, which effectively improves the identification accuracy and robustness of the current road types. At the same time, the predicted time of a single frame image on a specific test platform is about 0.028 6 s, which meets the real-time requirements.
- Published
- 2021
- Full Text
- View/download PDF
20. Numerical analysis on tractive performance of off-road tire on gravel road using a calibrated finite element method–discrete element method model and experimental validation
- Author
-
Mengyan Zang, Haiyang Zeng, Peng Yang, and Weipan Xu
- Subjects
0209 industrial biotechnology ,business.industry ,Mechanical Engineering ,Numerical analysis ,Aerospace Engineering ,Terrain ,04 agricultural and veterinary sciences ,02 engineering and technology ,Structural engineering ,Experimental validation ,Discrete element method ,Finite element method ,020901 industrial engineering & automation ,Gravel road ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,business ,Geology - Abstract
The interaction between off-road tires and granular terrain has a great influence on the tractive performance of off-road vehicles. However, the finite element method or the discrete element method cannot effectively study the interaction between off-road tires and granular terrain. The three-dimensional combined finite element and discrete element method is applied to handle this problem. In this study, a calibrated finite element method–discrete element method model is established, in which the finite element model of off-road tire is validated by stiffness tests, while the discrete element model of gravel particles is validated by triaxial compression tests. The calibrated finite element method–discrete element method model can describe the structural mechanics of the off-road tire and the macroscopic mechanical properties of the gravel road. Tractive performance simulations of the off-road tire on gravel road under different slip conditions are performed with the commercial software LS-DYNA. The simulation results are basically corresponded with the soil-bin test results in terms of granular terrain deformation and tractive performance parameters versus the slip rates. Finally, the effects of tread pattern, wheel load, and tire inflation pressure on tractive performance of off-road tire on granular terrain are investigated. It indicates that the calibrated finite element method–discrete element method can be an effective tool for studying the tire–granular terrain interaction and predicting the tractive performance of off-road tire on granular terrain.
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- 2020
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21. Assessing the applicability of the highway safety manual to gravel roads: A case study of Wyoming
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Omar Albatayneh, Khaled Ksaibati, and Ahmed Farid
- Subjects
050210 logistics & transportation ,Gravel road ,0502 economics and business ,05 social sciences ,Forensic engineering ,Environmental science ,0501 psychology and cognitive sciences ,Transportation ,Highway Safety Manual ,Safety Research ,050107 human factors - Abstract
Gravel road safety is a crucial area of road safety since gravel roads represent a substantial proportion of the entirety of the nation’s roadway network. Also, gravel roads pose inherent hazards t...
- Published
- 2020
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- View/download PDF
22. Complementary Modeling of Gravel Road Traffic-Generated Dust Levels Using Bayesian Regularization Feedforward Neural Networks and Binary Probit Regression
- Author
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Ahmed Farid, Milhan Moomen, Khaled Ksaibati, and Omar Albatayneh
- Subjects
050210 logistics & transportation ,Artificial neural network ,Computer science ,05 social sciences ,0211 other engineering and technologies ,Binary number ,02 engineering and technology ,Function (mathematics) ,computer.software_genre ,Mechanics of Materials ,Gravel road ,Probit model ,021105 building & construction ,0502 economics and business ,Feedforward neural network ,Data mining ,computer ,Model building ,Civil and Structural Engineering ,Parametric statistics - Abstract
Gravel roads require extensive maintenance and rehabilitation. That is because of the dynamic behavior of gravel road conditions. This study is aimed at investigating road condition factors affecting the traffic-generated dust on gravel roads. The study concerns Laramie County, Wyoming. The parametric binary probit regression structure and the non-parametric Bayesian regularization artificial neural network (BRANN) methods were implemented to model traffic-generated dust levels as a function of the factors that contribute to dust generation. The BRANNs method simplifies the model building process by precluding irrelevant and redundant weights of artificial neural networks (ANNs). In this study, the BRANN method is utilized with one single hidden layer using the MATLAB® function for neural networks. In the hidden layer, multiple neuron counts ranging from three to thirty were attempted. The parametric and non-parametric techniques mentioned were adopted to provide comprehensive insights into important factors that contribute to dust generation. Therefore, both techniques complement each other. A total of 206 gravel road segments were used for model building for both analyses. As per the results of the BRANN model, it was found that twenty neurons produced the most accurate results. Furthermore, it was found that the BRANN model had more variables than the binary probit regression model, whereas the probit model provided general insights into the factors affecting the dust on gravel roads such as average travel speed and soil type. Also, it would be an easy-to-use method to assist local agencies and DOT practitioners in addressing the dust problems on gravel roads.
- Published
- 2020
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23. Research on Motor Transport Produced Noise on Gravel and Asphalt Roads
- Author
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Linas Leipus, Donatas Butkus, and Tomas Januševičius
- Subjects
motor transport ,noise level ,max noise level ,reciprocal noise level ,gravel road ,asphalt pavement (ap) ,Highway engineering. Roads and pavements ,TE1-450 ,Bridge engineering ,TG1-470 - Abstract
Vehicles in motion on roads are the main source of noise in the environment. The noise in a car is created by structural noises from car construction, originated from vibrations in an engine, cabin, silencer, wheels and tires. Traffic noise flow depends on its intensity, motion speed, flow composition and extent, quality of the road pavement and build-up of the area along the road. This paper contains research on motor transport produced noise levels on roads of regional signifi cance with gravel and asphalt pavement in Molėtai district. The level of motor transport produced noise was measured in wintertime and summertime at the chosen typical locations considering the nature of the asphalt and gravel road pavement and diff erent landscape morphology forests, topography roughness, open area, upslope, downslope, etc. Also, research of noise level dependence on car speed was performed from 50 km/h to 70 km/h. It was determined during the study that noise level produced by a car moving at a speed of 50 km/h on a road with gravel pavement is higher by 4 dBA than that on a road with asphalt pavement. Upon moving away from the noise source by 50 m, the level of noise decreases by 12 dBA in woodland open areas and by 16 dBA. As car speed increases from 40 km/h to 50 km/h in wintertime, the level of noise rises by 2 dBA. In summertime, as car speed increases from 50 km/h to 70 km/h, the noise level rises by 5 dBA. These differences are due to the presence of ice and snow on the road in winter. Noise depends on physical properties of tires, type of pavement, car vibrations and in particular on pavement roughness.
- Published
- 2010
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24. Possibilities for the Improvement of the Quality of Design Solutions in the Gravel Road Reconstruction Projects
- Author
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Vilimas Gintalas
- Subjects
gravel road ,road alignment ,geometrical parameters ,horizontals curves ,design solution ,Highway engineering. Roads and pavements ,TE1-450 ,Bridge engineering ,TG1-470 - Abstract
This summary of the author’s PhD thesis supervised by Prof Dr Donatas Čygas and defended on 25 February 2010 at the Vilnius Gediminas Technical University. The thesis is written in Lithuanian and is available from the author upon request. Chapter 1 gives analysis of Gravel Road Network and analysis of gravel roads Development in the Republic of Lithuania. Chapter 2 gives analysis of the road design standards of the Republic of Lithuania and foreign countries. Chapter 3 gives methodology of experimental investigations. Chapter 4 gives results of experimental investigations. Chapter 5 gives generalization of investigation results.
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- 2010
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25. Green, Green Grass of Home
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Te Atamea Boynton
- Subjects
Mining engineering ,Gravel road ,Geology ,Front (military) - Abstract
Our old grey Subaru crept slowly up the dusty gravel road. It was a muggy evening, but you couldn’t turn the air con on or open any windows unless you wanted a car full of dust. I got to sit in the front for this last stretch to Nanny’s, so I oversaw switching out Dad's Prince Tui Teka CDs. Dad went extra slow so as not to scratch the discs, but that was hard on a gravelly road full of potholes.
- Published
- 2021
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26. Does Increased Road Dust Due to Energy Development Impact Wetlands in the Bakken Region?
- Author
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Creuzer, Jessica, Hargiss, Christina, Norland, Jack, DeSutter, Thomas, Casey, Francis, DeKeyser, Edward, and Ell, Mike
- Subjects
EMISSIONS (Air pollution) ,WETLANDS ,ENERGY development ,GRAVEL roads ,BAKKEN Formation ,DUST - Abstract
The Bakken region of western North Dakota and Montana from January 2012 to December 2013 saw an increase of 3368 oil wells, causing a major increase in road dust emissions. A portion of the energy extraction in the Bakken occurs in the wetland rich Prairie Pothole Region, and there is little information on gravel road dust emissions or the ecological impacts. The objectives of this study were to (1) estimate surface loading of gravel road dust during different times of year and at different distances from the road, (2) evaluate dust loading effects on surface water quality, and (3) evaluate the impact of dust deposition on wetland soils. Ten wetlands were tested in the energy impacted area and ten in an adjacent area without energy development. There was a 355 % increase in dust loading 10 m from the road in the energy impacted area compared to an area without energy development; meanwhile, there was only a 46 % increase in dust loading 40 m from the road. This loading resulted in an annual deposition of 647 g/m of gravel road dust close to the road. However, the effect of dust loading on the water quality and soils of wetlands was minimal when compared to wetlands not impacted by increased gravel road dust. The finding of minimal effect on wetland resources from increased road dust fills a knowledge gap in the Bakken on how energy development alters the environment. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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27. Numerical Parametric Study on Development of Gravel Road Corrugation
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Taeyoung Yun and Hee Mun Park
- Subjects
Gravel road ,Geotechnical engineering ,Development (differential geometry) ,Geology ,Parametric statistics - Published
- 2019
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28. Developing and validating an image processing algorithm for evaluating gravel road dust
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Omar Albatayneh, Lars Forslöf, and Khaled Ksaibati
- Subjects
050210 logistics & transportation ,Data collection ,Computer science ,05 social sciences ,0211 other engineering and technologies ,Image processing ,02 engineering and technology ,Track (rail transport) ,Maintenance planning ,GeneralLiterature_MISCELLANEOUS ,Mechanics of Materials ,Gravel road ,021105 building & construction ,0502 economics and business ,Digital image processing ,Management system ,Statistical analysis ,Algorithm ,Civil and Structural Engineering - Abstract
Daily traffic on arid gravel roads can easily generate dust. Dust emitted from gravel roads creates several problems such as aggravated asthma, breathing difficulties, reducing crop yields, and even death. Therefore, local agencies tend to track the dust amounts on the gravel roads in order to maintain them in good conditions. An accurate detection of dust amounts is very crucial in Gravel Roads Management System (GRMS). Data collection is considered as one of the main challenges facing local agencies due to budget constraints. This paper establishes a novel method for an automatic recognition of dust amounts on gravel roads. This algorithm, “Simple Dust Classification Algorithm”, uses images taken from smartphone application, “Road roid”, to classify dust amounts by using proprietary Digital Image Processing algorithms. A Dustometer device was used to validate the proposed algorithm. Dustometer measurements, supported by statistical analysis, demonstrate that the proposed algorithm achieves an outstanding dust amount classification accuracy. Hence, the proposed algorithm is a promising alternative to assist local agencies in data collection and maintenance planning.
- Published
- 2019
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29. Economics of upgrading gravel roads to Otta seal surface
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Yang Zhang, Halil Ceylan, Sunghwan Kim, Douglas D. Gransberg, Ali Nahvi, Sharif Y. Gushgari, Ali Arabzadeh, and Charles T. Jahren
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Low volume ,Economics and Econometrics ,Upgrade ,Aggregate (composite) ,Gravel road ,Economics ,Cost analysis ,Economic analysis ,Investment (macroeconomics) ,Civil engineering ,Seal (mechanical) - Abstract
Maintenance of low volume roads especially gravel roads is costly, and millions of funding annually are spent for aggregate replacement alone. Otta seal, compared to other bituminous surface treatments (BSTs) for low volume roads that require high-quality materials and specialized expertise, can be constructed using cheaper local aggregates and accessible equipment. However, only three states have reported Otta seal constructions and performance in the US. In this study, an economic analysis was conducted to compare the cost of maintaining a gravel road to the cost of upgrading an existing gravel road to a double Otta seal surface. This analysis was conducted at three levels: deterministic life-cycle cost analysis (LCCA), a stochastic Monte Carlo simulation-based LCCA, and a traffic based economic analysis. A generic one-mile rural road in Midwest was considered as a case study location. Although, according to the analysis conducted in this paper, an upgrade to Otta seal investment might be justif...
- Published
- 2019
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30. Damage, brittle fracture resistance and working capacity of a KAMAZ vehicle leaf spring when operating in the North
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S.N. Makharova, Irina Buslaeva, S.P. Yakovleva, and A.I. Levin
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Truck ,Resistance (ecology) ,Working capacity ,02 engineering and technology ,021001 nanoscience & nanotechnology ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Leaf spring ,Gravel road ,Environmental science ,Geotechnical engineering ,0210 nano-technology ,Material properties ,Embrittlement ,Brittle fracture ,Earth-Surface Processes - Abstract
Due to importance of developing the North and Arctic territories, it is essential to ensure working capacity of machinery in cryolithozone. To solve these problems, it is necessary to study accumulation of structural damage and changes in material properties. The purpose of this article is to study influence of operation in the northern roads conditions on fatigue damage, brittle fracture resistance and the working capacity of a leaf spring of a KAMAZ truck widely used in Yakutia. Methods of mathematical statistics, metallography, microindentation, standard mechanical tests, etc. were applied. Results of analysis of distribution of the KAMAZ vehicle springs failures on the months of the year are given, taking into account the seasonal changes in a profile of the typical for Yakutia gravel road. To assess the fatigue damage of metal, the structural and statistical study of microhardness (microdamage) and porosity (mesodamage) was carried out. Impact toughness values were determined and it was found that the accumulated damage did not lead to metal embrittlement at low temperatures. The more significant impact of the cryolithozone road microprofile on the working capacity of the KAMAZ truck springs as compared to the factor of the low temperatures has been substantiated.
- Published
- 2019
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31. Quantification and Characterization of Particulate Matter Generated from Unpaved Roads in the Oil Development Area of Western North Dakota
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Sumon Datta, Shafiqur Rahman, Md Saidul Borhan, Bernhardt Saini-Eidukat, Larry Cihacek, and Kris Ringwall
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010504 meteorology & atmospheric sciences ,Soil test ,Biomedical Engineering ,Air pollution ,Soil Science ,Forestry ,010501 environmental sciences ,Particulates ,medicine.disease_cause ,01 natural sciences ,Geography ,Environmental chemistry ,Gravel road ,medicine ,Effective treatment ,Agronomy and Crop Science ,Chemical composition ,Inductively coupled plasma mass spectrometry ,Air quality index ,0105 earth and related environmental sciences ,Food Science - Abstract
Heavy vehicle traffic on unpaved roads in western North Dakota, due to increasing oil extraction activities, is generating coarse particulate matter (PM10) and fine PM (PM2.5), and total suspended particles (TSP), potentially raising concerns for animal and human health and impacts on crop and plant growth. However, limited quantification and characterization are available for PM from unpaved roads next to oil activities. Therefore, a study was conducted to characterize and quantify the PM concentrations from heavy traffic on unpaved roads due to increasing oil activities in western North Dakota. Three unpaved road sites were selected and paired with application of two dust suppressants (brine and magnesium chloride). MiniVol air samplers were used to quantify PM, scanning electron microscopy (SEM) was used to characterize the minerals in PM samples, and inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze the chemical composition of soil samples. The average PM10 and PM2.5 concentrations were higher at site 2 (untreated loose gravel road) than at site 1 (periodically treated with dust suppressants) during the study period (2015-2016). In addition, the PM concentrations were lower in 2016 because of decreased oil activities at site 2. Statistical analyses revealed that the PM concentrations were mostly correlated with vehicle count in addition to temperature, wind direction, and rainfall. Magnesium chloride was the most effective treatment for reducing PM. The SEM analyses of PM samples revealed that most particulates were quartz, other silicates, or biogenic particles. Soil sample analyses revealed that the concentrations of most elements were lower than the threshold values set by the USGS National Geochemical Survey. Keywords: Air pollution, Air quality, Dust, North Dakota, Oil development, Particulate matter.
- Published
- 2019
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32. Classification of the Acoustics of Loose Gravel
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Moudud Alam, Nausheen Saeed, Roger G. Nyberg, Pascal Rebreyend, Mark Dougherty, and Diala Jooma
- Subjects
gravel roads ,loose gravel ,ensemble bagged trees ,sound analysis ,road maintenance ,GoogLeNet ,Computer and Information Sciences ,Computer science ,Acoustics ,Reliability (computer networking) ,0211 other engineering and technologies ,TP1-1185 ,02 engineering and technology ,Biochemistry ,Convolutional neural network ,Article ,Analytical Chemistry ,Gravel road ,021105 building & construction ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Instrumentation ,Slip (vehicle dynamics) ,business.industry ,Chemical technology ,Deep learning ,Supervised learning ,Reproducibility of Results ,Data- och informationsvetenskap ,Atomic and Molecular Physics, and Optics ,Tree (data structure) ,Sound ,Spectrogram ,020201 artificial intelligence & image processing ,Artificial intelligence ,Neural Networks, Computer ,business ,Algorithms - Abstract
Road condition evaluation is a critical part of gravel road maintenance. One of the assessed parameters is the amount of loose gravel, as this determines the driving quality and safety. Loose gravel can cause tires to slip and the driver to lose control. An expert assesses the road conditions subjectively by looking at images and notes. This method is labor-intensive and subject to error in judgment, therefore, its reliability is questionable. Road management agencies look for automated and objective measurement systems. In this study, acoustic data on gravel hitting the bottom of a car was used. The connection between the acoustics and the condition of loose gravel on gravel roads was assessed. Traditional supervised learning algorithms and convolution neural network (CNN) were applied, and their performances are compared for the classification of loose gravel acoustics. The advantage of using a pre-trained CNN is that it selects relevant features for training. In addition, pre-trained networks offer the advantage of not requiring days of training or colossal training data. In supervised learning, the accuracy of the ensemble bagged tree algorithm for gravel and non-gravel sound classification was found to be 97.5%, whereas, in the case of deep learning, pre-trained network GoogLeNet accuracy was 97.91% for classifying spectrogram images of the gravel sounds.
- Published
- 2021
33. Beräkningsmodell för ekonomiska och miljömässiga effekter vid grusvägsunderhåll
- Author
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Svensson, Nea and Svensson, Nea
- Abstract
En beräkningsmodell utvecklas för att skatta miljöpåverkan och ekonomiska effekter vid vägunderhållet grusning. Beräkningsmodellen används för att kunna jämföra alternativa metoder för grusning. Beräkningsmodellen testas genom ett testscenario med tre alternativa metoder för grusning. I alternativ ett används nytt grus och i alternativ två och tre används återvunnet grus. Studiens resultat visar att beräkningsmodellen kan användas för att skatta kostnad och miljöbelastning. Testscenariot visar att det är ekonomiskt och miljömässigt fördelaktigt att använda återvunnet grus vid grusning. Ur ett samhällsperspektiv är det viktigt att belysa fördelarna med att använda återvunnet grus, då detta kan motivera att fler faktiskt väljer detta alternativ och då brytning av naturgrus är en energikrävande process som påverkar miljön negativt. Studiens syfte är att skapa förståelse för miljömässiga och ekonomiska effekter vid återvinning av grus vid grusvägsunderhåll. För att uppnå syftet genomförs en fallstudie som besvarar frågeställningen hur miljömässiga och ekonomiska effekter kan skattas på grusvägsunderhåll., A calculation model is developed to estimate the environmental impact and economic effects of gravel road maintenance. The purpose of the calculation model is to be able to compare alternative methods for graveling. The calculation model is tested through a test scenario with three alternative methods for graveling. In alternative one, new gravel is used and in alternatives two and three recycled gravel is used. The study's results show that the model calculation can be used to estimate cost and environmental impact. The test scenario shows that it is economically and environmentally advantageous to use recycled gravel in graveling. From a societal perspective, it is important to highlight the benefits of using recycled gravel, as this may motivate more people to actually choose this alternative. Because mining of natural gravel is an energy-intensive process that has a negative impact on the environment. The purpose of the study is to create an understanding of the environmental and economic effects of recycling of gravel during gravel road maintenance. To achieve this, a case study is conducted that answers the question how environmental and economic impacts can be estimated on gravel road maintenance.
- Published
- 2020
34. The analysis of traffic accidents on Lithuanian regional gravel roads
- Author
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Stanislav Mamčic and Henrikas Sivilevičius
- Subjects
road ,gravel road ,gravel pavement ,traffic accident ,traffic volume ,traffic speed ,Transportation engineering ,TA1001-1280 - Abstract
A great number of serious road accidents occur all over the world every year. In spite of some progress in this area, road traffic safety has remained an acute problem in recent years. Traffic accidents on the road depend on the following factors: road traffic volume, road traffic speed, road condition, weather conditions for traffic, driving experience and driving culture. All these factors are related to traffic safety, human lives and health. The main goal of this work is to provide a statistical analysis of traffic accidents and investigate the causes, structure, dynamics and seasonal character of traffic accidents on Lithuanian regional gravel roads. It has been established that seasons play an important role for traffic accidents on regional gravel roads in Lithuania. Rates for traffic accidents increase from spring to autumn. The number of traffic accidents on Lithuanian roads decreased considerably in 2008 and 2009.
- Published
- 2013
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35. Evaluation of the Performance of Gravel Road with Base Course Reinforced with Do-Nou
- Author
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Daisuke Suetsugu, Atsushi Koyama, Yoshinori Fukubayashi, and Sohei Sato
- Subjects
Transport engineering ,Base course ,Computer science ,Settlement (structural) ,Trafficability ,Lateral earth pressure ,Gravel road ,Road surface ,Geotextile ,Subgrade - Abstract
In developing countries, improvement of trafficability of rural roads, which are generally earth or graveled, are crucial for rural development. Under the circumstances with financial constraints of those countries, locally available material-based approach towards improvement of trafficability are regarded as one of the practical measures. Do-nou, which is Japanese term for soilbag, have been utilized for reinforcing base course. Do-nou method is requiring only labor even for compaction of base material and used polyester fiber woven bags for crops, fertilizer, etc. as one of geotextile. In 29 countries of Asia, Africa and the Pacific, about 180 km rural road has been improved using the Do-nou method, by the NGO which one of the authors is belong to. Because of the easiness and effectiveness of Do-nou method, it enables minor and small enterprises, generally operated by the youth, to be involved in road construction implemented by public works. In order to improve trafficability of rural roads while solving social problem, high unemployment rate among the youth in developing countries, the method needs to be adopted by road authorities for further extension. In this study, therefore, the performance of gravel road with base course consist of Do-nou have been evaluated through the series of full-size driving tests. The settlement of road surfaces with conventionally designed base course and with that consist of Do-nou with the same thickness subjected to the traffic load were measured and compared. Dynamic cone penetration index of these base course structure was also compared. Load distribution effects were also examined using earth pressure gages located on subgrade and road surface during driving tests. The mechanism of reducing settlement of road surface with Do-nou base course were verified. The performance of base course with Do-nou are defined in comparison to conventional base course structure, which enable road authorities adopt Do-nou method.
- Published
- 2020
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36. Comparison of Pattern Recognition Techniques for Classification of the Acoustics of Loose Gravel
- Author
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Diala Jomaa, Pascal Rebreyend, Roger G. Nyberg, Nausheen Saeed, Moudud Alam, and Mark Dougherty
- Subjects
0209 industrial biotechnology ,Relation (database) ,Computer science ,business.industry ,Acoustics ,Decision tree ,Pattern recognition ,02 engineering and technology ,Vegetation ,Tree (data structure) ,Statistical classification ,020901 industrial engineering & automation ,Gravel road ,Pattern recognition (psychology) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Artificial intelligence ,business - Abstract
Road condition evaluation is a critical part of gravel road maintenance. One of the parameters that are assessed is loose Gravel. An expert does this evaluation by subjectively looking at images taken and written text for deciding on the road condition. This method is labor-intensive and subjected to an error of judgment; therefore, it is not reliable. Road management agencies are looking for more efficient and automated objective measurement methods. In this study, acoustic data of gravel hitting the bottom of the car is used, and the relation between these acoustics and the condition of loose gravel on gravel roads is seen. A novel acoustic classification method based on Ensemble bagged tree (EBT) algorithm is proposed in this study for the classification of loose gravel sounds. The accuracy of the EBT algorithm for Gravel and Nongravel sound classification is found to be 97.5. The detection of the negative classes, i.e., non- gravel detection, is preeminent, which is considerably higher than Boosted Trees, RUSBoosted Tree, Support vector machines (SVM), and decision trees.
- Published
- 2020
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37. A Review of Intelligent Methods for Unpaved Roads Condition Assessment
- Author
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Diala Jomaa, Pascal Rebreyend, Roger G. Nyberg, Nausheen Saeed, and Mark Dougherty
- Subjects
Transport engineering ,050210 logistics & transportation ,Computer science ,ComputerSystemsOrganization_MISCELLANEOUS ,Gravel road ,010401 analytical chemistry ,0502 economics and business ,05 social sciences ,01 natural sciences ,Condition assessment ,0104 chemical sciences ,Task (project management) - Abstract
Conventional road condition evaluation is an expensive and time-consuming task. Therefore data collection from indirect economical methods is desired by road monitoring agencies. Recently intelligent road condition monitoring has become popular. More studies have focused on automated paved road condition monitoring, and minimal research is available to date on automating gravel road condition assessment. Road roughness information gives an overall picture of the road but does not help in identifying the type of defect; therefore, it cannot be helpful in the more specific road maintenance plan. Road monitoring can be automated using data from conventional sensors, vehicles' onboard devices, and audio and video streams from cost-effective devices. This paper reviews classical and intelligent methods for road condition evaluation in general and, more specifically, reviews studies proposing automated solutions targeting gravel or unpaved roads.
- Published
- 2020
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38. Investigations of Gravel Road Dust Minimization by Applying Different Salt Solutions.
- Author
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Bradulienė, Jolita and Vasarevičius, Saulius
- Subjects
- *
GRAVEL roads , *CALCIUM chloride , *PARTICULATE matter , *AIR pollutants , *ENVIRONMENTAL protection , *ENVIRONMENTAL engineering , *ENVIRONMENTAL sciences - Abstract
Dust on gravel roads is reduced through the application of various dust minimization materials, most frequently calcium chloride. However, global efforts have been intensified to find new effective materials that cause the least damage to the environmental. One of them is Safecote, a new patented product. In 2008 measurements were performed on the gravel road Jusevičiai-Būdvietis-Derviniai, which was treated with calcium chloride. Experiments of particulate matter concentrations in the air, when gravel road pavement was treated with a mixture of calcium chloride and Safecote, were carried out in the summer of the same year. As the findings of the experimental investigation of particulate matter concentrations in the air show, the concentration of particulate matter on the gravel road treated with calcium chloride alone reached, on average, 1.90 mg/m³, while on that treated with the mixture was 0.40 mg/m³. [ABSTRACT FROM AUTHOR]
- Published
- 2014
39. An alternative method for determining particle-size distribution of forest road aggregate and soil with large-sized particles.
- Author
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Rhee, Hakjun, Foltz, Randy B., Fridley, James L., Krogstad, Finn, and Page-Dumroese, Deborah S.
- Subjects
- *
PARTICLE size distribution , *FOREST roads , *GRAVEL roads , *SOIL sampling - Abstract
Measurement of particle-size distribution (PSD) of soil with large-sized particles (e.g., 25.4 mm diameter) requires a large sample and numerous particle-size analyses (PSAs). A new method is needed that would reduce time, effort, and cost for PSAs of the soil and aggregate material with large-sized particles. We evaluated a nested method for sampling and PSA by comparing it with the methods that follow the American Association of State Highway and Transportation Officials (AASHTO) standard T88-00 and the American Society for Testing and Materials (ASTM) standard D422-63. Using 33 forest road aggregate samples from the Clearwater National Forest in northern Idaho, the nested method required much less laboratory time and effort and resulted in similar PSA values, except for the 0.149 mm (No. 100) sieve, where the smallest particle-size fraction (PSF) values (1.30% and 1.39%) were observed. The nested method shows great potential for determining PSDs of the soil and aggregate material with large-sized particles and should be tested on other forest soils and road aggregates. The nested sampling and analysis method allows for the same number of samples to be collected but requires less laboratory time, making it more efficient and economical for testing the soil and aggregate material with large-sized particles such as forest road aggregate. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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40. Investigations and Mitigation Measures of Landslide Affected Areas in Hill Roads of East Africa—Case Study on Projects of Ethiopia
- Author
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S. Sailesh, Pradyot Biswas, and Avik Kumar Mandal
- Subjects
Hydrology ,Berm ,Culvert ,Gravel road ,East africa ,Landslide ,Drainage ,Retaining wall ,Geology ,Natural (archaeology) - Abstract
Under the road development programme of Ethiopian Roads Authority (ERA) in Ethiopia, many roads spreading all over the country were upgraded from the existing gravel road to the widened asphalt road. Due to the rugged and mountainous terrain condition, natural and man-made slope failures such as landslides usually occur in almost all the hilly and mountainous terrain in Ethiopia. The main cause for the occurrences of failures at different locations along project roads which were widened either by cutting the hill slope and/or filling the valley slope was high rainfall in the area during the month of June to September. In this paper, the case study on the investigations of landslide failures along hill slope, valley slope, slope of bridge approaches, slope of hillside on upstream and valley side on downstream of culverts along project roads is described. The analysis of landslides and its different methods of mitigation measures, namely flattening of slope with or without provision of intermediate berms, provision of lateral support by gravity retaining wall at toe of hill slope or at road edge on valley slope side including proper slope protection and drainage measures adopted in the rehabilitation works along different project roads in Ethiopia, are presented here.
- Published
- 2020
- Full Text
- View/download PDF
41. Image Retraining Using TensorFlow Implementation of the Pretrained Inception-v3 Model for Evaluating Gravel Road Dust
- Author
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Khaled Ksaibati, Lars Forslöf, and Omar Albatayneh
- Subjects
Computer science ,business.industry ,Deep learning ,Feature extraction ,0211 other engineering and technologies ,Retraining ,020101 civil engineering ,Image processing ,02 engineering and technology ,Machine learning ,computer.software_genre ,Convolutional neural network ,0201 civil engineering ,Image (mathematics) ,Gravel road ,021105 building & construction ,Management system ,Artificial intelligence ,business ,computer ,Civil and Structural Engineering - Abstract
In gravel roads management systems (GRMS), the need for a holistic approach for detecting the dust amounts on gravel roads has enabled the development of a solution that works based on one ...
- Published
- 2020
- Full Text
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42. Numerical Model to Optimize Selection of Unpaved Roads for Dust Suppressing Chemical Treatments: Case Study
- Author
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Khaled Ksaibati, Promothes Saha, and Nikolai A. Greer
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Chemical treatment ,Gravel road ,021105 building & construction ,0211 other engineering and technologies ,Environmental engineering ,Environmental science ,020101 civil engineering ,02 engineering and technology ,Unpaved road ,Selection (genetic algorithm) ,0201 civil engineering ,Civil and Structural Engineering - Abstract
This study developed a model to select the optimum sections of unpaved roads for chemical treatments as dust suppressants within a limited budget. In the state of Wyoming, more than 19,312 ...
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- 2020
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43. Calculation model for the economic and environmental effects during gravel road maintenance
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Svensson, Nea
- Subjects
Grusväg ,Gravel ,cost comparison ,Grusåtervinning ,Grus ,Gravel recycling ,Skattning av miljöpåverkan ,Road maintenance ,Teknik och teknologier ,Environmental impact estimation ,Engineering and Technology ,Kostnadsjämförelse ,Gravel road ,Vägunderhåll - Abstract
En beräkningsmodell utvecklas för att skatta miljöpåverkan och ekonomiska effekter vid vägunderhållet grusning. Beräkningsmodellen används för att kunna jämföra alternativa metoder för grusning. Beräkningsmodellen testas genom ett testscenario med tre alternativa metoder för grusning. I alternativ ett används nytt grus och i alternativ två och tre används återvunnet grus. Studiens resultat visar att beräkningsmodellen kan användas för att skatta kostnad och miljöbelastning. Testscenariot visar att det är ekonomiskt och miljömässigt fördelaktigt att använda återvunnet grus vid grusning. Ur ett samhällsperspektiv är det viktigt att belysa fördelarna med att använda återvunnet grus, då detta kan motivera att fler faktiskt väljer detta alternativ och då brytning av naturgrus är en energikrävande process som påverkar miljön negativt. Studiens syfte är att skapa förståelse för miljömässiga och ekonomiska effekter vid återvinning av grus vid grusvägsunderhåll. För att uppnå syftet genomförs en fallstudie som besvarar frågeställningen hur miljömässiga och ekonomiska effekter kan skattas på grusvägsunderhåll. A calculation model is developed to estimate the environmental impact and economic effects of gravel road maintenance. The purpose of the calculation model is to be able to compare alternative methods for graveling. The calculation model is tested through a test scenario with three alternative methods for graveling. In alternative one, new gravel is used and in alternatives two and three recycled gravel is used. The study's results show that the model calculation can be used to estimate cost and environmental impact. The test scenario shows that it is economically and environmentally advantageous to use recycled gravel in graveling. From a societal perspective, it is important to highlight the benefits of using recycled gravel, as this may motivate more people to actually choose this alternative. Because mining of natural gravel is an energy-intensive process that has a negative impact on the environment. The purpose of the study is to create an understanding of the environmental and economic effects of recycling of gravel during gravel road maintenance. To achieve this, a case study is conducted that answers the question how environmental and economic impacts can be estimated on gravel road maintenance.
- Published
- 2020
44. Small-scale race events in natural areas: Participants’ attitudes, beliefs, and global perceptions of leave no trace ethics
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B. Derrick Taff, Jeremy Wimpey, Alan R. Graefe, and J. Tom Mueller
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Public land ,Event (computing) ,05 social sciences ,Exploratory research ,010501 environmental sciences ,01 natural sciences ,Trace (semiology) ,Race (biology) ,Tourism, Leisure and Hospitality Management ,Gravel road ,Scale (social sciences) ,0502 economics and business ,Marketing ,Psychology ,Recreation ,050212 sport, leisure & tourism ,0105 earth and related environmental sciences - Abstract
Small-scale race events are a popular form of recreation in natural areas with the potential for social and environmental impacts. Leave No Trace-based communication and education strategies are the most prevalent form of mitigating recreation impacts on public lands. To understand competitive race participants’ perceptions of Leave No Trace, this exploratory study compared race event participants’ attitudes, evaluative beliefs, and global perceptions of Leave No Trace by event type: gravel road running, trail running, mountain biking, and motorcycle trail racing. Data were collected using online post-event surveys. Participants were sampled from five competitive race events on public land held during fall 2015 to summer 2016. Significant differences between event types were found for all constructs examined. Motorcycle racers were the least likely to agree that Leave No Trace is an effective method for protecting the environment, least likely to believe that humans have the potential to cause social or environmental impacts, and were the least willing to change their behavior if they found out it was damaging the environment. Runners’ attitudes toward specific Leave No Trace behaviors were the least in line with Leave No Trace recommendations, while mountain bikers were the most in-line. Management implications When issuing permits and managing events on public natural areas, managers should approach each affair differently, realizing that the type of event may influence the level of social and ecological impact. Managers should contact event organizers as early as possible to raise awareness of possible impacts, provide tailor-made messaging to participants, and develop management plans specific to the event and location that monitor and adaptively manage impacts to preserve social experiences and ecological resources. This will help managers remain flexible in their event management.
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- 2018
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45. Biofuel ash in road stabilization – Lessons learned from six years of field testing
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Desiree Nordmark, Anders Lagerkvist, Jenny Vestin, Maria Arm, and Bo B. Lind
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Pulp mill ,Waste management ,0211 other engineering and technologies ,020101 civil engineering ,Transportation ,02 engineering and technology ,Geotechnical Engineering and Engineering Geology ,Monitoring program ,0201 civil engineering ,Biofuel ,Gravel road ,Fly ash ,021105 building & construction ,Environmental science ,Civil and Structural Engineering - Abstract
In 2009, pulp mill fly ash was used for stabilizing the road base of a low-volume gravel road. Six years after stabilization, a two-year monitoring program and a complementary study were conducted ...
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- 2018
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46. Numerical Analysis of the Initiation and Development of Corrugation on a Gravel Road
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Taeil Chung, Hyu-Soung Shin, and Taeyoung Yun
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0209 industrial biotechnology ,020901 industrial engineering & automation ,0203 mechanical engineering ,Numerical analysis ,Gravel road ,020302 automobile design & engineering ,Geotechnical engineering ,Development (differential geometry) ,02 engineering and technology ,Multibody system ,Discrete element method ,Geology - Published
- 2018
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47. ANALYSIS THE IMPACT OF GOVERNMENT PROLIFERANTION ON EDUCATIONAL AND ECONOMIC
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Rumayya Rumayya and Dalila Husna
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Government ,Poverty ,Difference in Difference ,Economic ,Per capita income ,Difference in differences ,Gravel road ,Local government ,Development economics ,Per capita ,Economics ,Public service ,Educational ,Government Proliferantion - Abstract
The government proliferantion in Indonesia become a consequence of the existence of a policy of fiscal desentalisasi. The existence of the government proliferantion is expected to shorten the span of control so that the goal of improving the well-being of society and the public service can be achieved. This study goals to analyze the impact of the government proliferantion on the regional educational and economic outcomes against on 491 Kabupaten/Kota in Indonesia. This research uses the Difference in Difference as a tool of analysis. Data obtained from the Indodapoer-World Bank year 2001 until 2014. The impact of the presence of the government proliferantion against outcomes education is lowering the level of literacy through a decrease in the number of buildings on the SD output though it is insignificant and its impact on economic outcomes effect increasing income per capita community that in proxy through household spending per capita and GDP per capita, increasing the number of workers, and lower levels of poverty through increased output in the electricity, road access to the village dirt road, and the village gravel road. The impact in General of the expansion area is a local Government has succeeded in transferring funds to the poor but not with a business climate that is shown by the results of the constant price GDP as a whole which indicates significant results negative. Keywords: Government Proliferantion, Difference in Difference, Educational, Economic.JEL : R1, H00, I21, I25
- Published
- 2021
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48. The analysis of traffic accidents on Lithuanian regional gravel roads.
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Mamčic, Stanislav and Sivilevičius, Henrikas
- Subjects
- *
TRAFFIC accidents , *GRAVEL roads , *TRAFFIC flow , *TRANSPORTATION industry - Abstract
A great number of serious road accidents occur all over the world every year. In spite of some progress in this area, road traffic safety has remained an acute problem in recent years. Traffic accidents on the road depend on the following factors: road traffic volume, road traffic speed, road condition, weather conditions for traffic, driving experience and driving culture. All these factors are related to traffic safety, human lives and health. The main goal of this work is to provide a statistical analysis of traffic accidents and investigate the causes, structure, dynamics and seasonal character of traffic accidents on Lithuanian regional gravel roads. It has been established that seasons play an important role for traffic accidents on regional gravel roads in Lithuania. Rates for traffic accidents increase from spring to autumn. The number of traffic accidents on Lithuanian roads decreased considerably in 2008 and 2009. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
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49. Effekt av dammbindningsmedel : en laboratoriestudie
- Author
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Arvidsson, Håkan, Jansson, Samuel, Arvidsson, Håkan, and Jansson, Samuel
- Abstract
I arbetet har kalciumklorid respektive magnesiumklorid utvärderats i kombination med fyra olika finmaterial (granit, amfibolit, metagråvacka samt naturlig silt) vilka används vid underhåll av grusvägar. Vattenlösningar av respektive salt har tillförts finmaterialet varefter regn och upptorkning har simulerats i laboratoriemiljö. Utvärdering har gjorts med avseende på mängden kvarvarande salt efter regnsimulering samt svepelektronmikroskopi (SEM) och optisk mikroskopi på finmaterialet efter upptorkning. Det har varit svårt att dra några slutsatser. Den framtagna försöksmetodiken har inte kunnat påvisa agglomerering i finfraktion av grusslitlager eller ge ledning till doseringsråd. Man kan se att kalciumklorid är effektivare per giva än magnesiumklorid. Det krävs mindre mängd salt (flingor) för att binda en viss mängd vatten med kalciumklorid än med magnesiumklorid vilket dock är känt sedan tidigare. Agglomerering kunde inte bevisas med upprepade försök. Kemiskt var det ingen större skillnad, salterna betedde sig snarlikt och enligt tidigare känt beteende. Skillnader av beteende beroende på typ av bergmaterial var försumbart i förhållande till salternas inverkan. Den allra största delen (som minst 80 %) av tillfört salt har lakats ur efter regnsimulering. Ingen skillnad mellan kalcium- och magnesiumklorid eller de olika finmaterialen kunde konstateras avseende urlakning. En liten skillnad mellan urlakning av katjoner och anjoner kunde konstateras där katjonerna hölls kvar i finmaterialet. Detta kan röra sig om en jonbytareffekt. Analys med SEM och optisk mikroskopi kunde inte påvisa några egentliga skillnader mellan de olika kombinationerna av salt respektive finmaterial. Vid upptorkning av finmaterialet kunde konstateras att kalciumklorid, räknat som handelsvara, kan absorbera mer vatten än magnesiumklorid. Denna effekt kvarstod även efter att regnsimulering har utförts. Den metod som utvecklades i samband med arbetet gav inga påvisbara skillnader, som inte var kända, In this study, calcium chloride and magnesium chloride have been evaluated in combination with four different fine materials (granite, amphibolite, meta greywacke and naturally occurring silt), which are used for gravel road maintenance. Aqueous solutions of the two salts have been added to the fine material where after rain and drying has been simulated under laboratory conditions. Evaluation has been performed in terms of residual amount of salt after rain simulation, and SEM and optical microscopy on the fine material after drying, respectively It has been difficult to draw any conclusions that would yield new information from the tests. The methodology developed was not able to show agglomeration in the fine fraction of the gravel road material and it was not possible to provide recommendations regarding the dosage of dust binding agents. The tests show that calcium chloride is more efficient in retaining moisture than magnesium chloride when the comparison is based on the amount of flakes used. Agglomeration could not be proven despite several repeated tests. The chemical properties did not differ significantly, the salts behaved similarly and according to earlier known data. Differences in the origin of rock material was negligible compared with the effects of the salts. The added salt was for the most part (with a minimum of 80%) leached out during the rain simulation. No differences between calcium chloride and magnesium chloride or between the different fine materials were observed in terms of leaching. A small difference between leaching of cations and anions was recorded where the cations were retained in the fine material. This might be an ion-exchange effect. Analysis with SEM and optical microscopy did not yield any significant differences between the different combinations of salt and fine materials, respectively. During drying of the fine material it was observed that calcium chloride, calculated as commercial product, could absorb more water than ma
- Published
- 2019
50. Effect of a Gravel Surface on Standing Balance and Overstepping in Walking.
- Author
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Kawanaka, Mayumi and Sasaki, Makoto
- Abstract
[Purpose] The aim of this study was to clarify the effect of a gravel surface on standing balance and overstepping an obstacle in walking. [Subjects] The subjects were 16 students. [Method] We measured center of gravity (COG) sway in static standing and the floor reaction force in overstepping an obstacle while walking on a flat surface and gravel. [Results] In quiet standing on the two surfaces, we found no significant differences for COG sway in path length, rectangular area, root mean square area, and the maximum amplitudes of sway in the X and Y directions. Compared with the flat surface, the floor reaction force in overstepping while walking on the gravel showed significant reductions in the second peak of vertical load and the anterior-posterior peak load. [Conclusion] The results reveal that the gravel surface had no effect on static balance, but in walking a defect appeared in double knee action, and the kick at the time of toe-off was weaker. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
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