Road Course Research Articles

High temperature impact on fatigue life of asphalt mixture in Slovakia

Temperature dependence of materials bonded with bitumen is a well-known fact. The impact of temperature changes the behaviour of asphalt mixtures from elastic to viscous state, and it also influences the complex modulus, phase angle and other properties of asphalt mixtures. This study observed the summer temperature influence on fatigue behaviour of an asphalt mixture for the surface course of roads in conditions of Slovakia. Measurements were made using the four-point bending method on the asphalt mixture with maximum grain size of 11 mm bonded with polymer modified bitumen. Summer conditions were represented by environmental temperature of 27 °C according to the Slovakian pavement design method. Ordinary temperatures for fatigue measurements are 10 °C, 15 °C and 20 °C according to European standards for asphalt mixture testing. Structural changes in the material were observed by dissipation energy calculations for each loading cycle. The aim of the study was to find out if the influence of high environmental temperature is positive or negative for the lifespan of asphalt mixtures.

MUSCULOSKELETAL INJURY RATES IN MULTIDAY MARATHON RUNNERS PERFORMING A REPEAT COURSE

BackgroundUltramarathon events are increasingly popular amongst non-elite athletes. However, there is little research investigating musculoskeletal injury rates, specifically multiday events using the same racing route.ObjectiveTo describe musculoskeletal injury rates in...

Strategic Analysis of Asset Securitization

Asset securitization is the cornerstone of modern financial prosperity, Chinese asset securitization is a microcosm of China's financial market reform. China's asset securitization road began in the 90s of last century, mainly through four stages of development: early exploration (1992-2004), pilot (2005-2008), stagnation reflection (2009-2011) and once again leave (2012 -2015). Although securitization has a complete modern financial process, but China's environment makes asset securitization road marked by a deep Chinese imprint, and formed a Chinese asset securitization basic features, which further reflects China are facing asset securitization challenge. The current Chinese economy has entered a new normal, asset securitization as an important tool for financing innovation, should play a more active role. Based on Chinese asset securitization road course, characteristics and challenges, strategic choice of Chinese paper asset securitization were thinking and analysis.

DETERMINANTS OF DRIVING ERRORS IN OLDER ADULTS

Objective 1: (Required) attending this session participants will be able to... : After attending the session, participants will be able to better describe driving errors made by older adults. Objective 2: (Required) attending this session participants will be able to... : After attending the session, participants will be able to better understand driving errors determinants. Objective 3: attending this session participants will be able to... : After attending the session, participants will be able to better discuss the different facets of driver safety. Abstract Body (Required; Limit 250 words) : The extent to which personality, deficits in specific cognitive domains, and self-assessment of cognitive and driving abilities contribute to older drivers' safety in complex real-world driving tasks is not well understood. In order to better understand driving errors made by adults being 70 years old and over a predriving assessment and an on-road test was conducted. We hypothesized that drivers over-estimating their own abilities will commit more driving errors. A convenience sample of 145 older drivers (mean age = 76 ± 4.1) completed a standardized road course conducted with a driving instructor and a human factors specialist who rated driving behaviors as well as driving performance. Participants also completed cognitive tests (UFOV, TMT A&B, Digit Symbol). They answered french versions of the big five inventory (20 items) and the CES-d depression scale (20 items) and rated their own cognitive and driving abilities. Relationships between the four domains previously described with the on-road performance will be studied through correlational analyses. Multivariate analyses will be conducted to explore the domains that can best predicted driving errors. Distinct facets of driver safety on road will be discussed. These findings will present preliminary evidence for the utility of personality assessments in identifying bias in driving self-evaluations, essential for safe self-regulation of driving.

Monitoring of Forest Hauling Roads Wearing Course Damage Using Unmanned Aerial Systems

Currently, a large part of the forest roads that were built using the bituminous surface technology in the second half of the last century have been worn out. This means that forest owners and forest managers urgently need to determine the amount and extent of this damage and establish a suitable repair plan, which demands both time and staff. The aim of the study is to verify whether it is possible, and with what precision, to detect the damage of the wearing course by means of unmanned aerial systems, which would facilitate and accelerate this process and possibly make it cheaper. A 3D model of a forest road was created using photos of the current state of a damaged part of a forest road. The aerial photographs were taken by an unmanned aircraft. To verify the accuracy of the model, cross sections of the road surface were surveyed tachymetrically and compared with the cross sections created in the 3D model in ArcMap, from photogrammetric pointcloud using aerial photographs from the unmanned aircraft. The RMSE of the values of the control points in the 3D model cross sections compared to the values of the points in the tachymetric measurement of the cross sections reached to within 0.0198 m. The results of the tested road section showed that the unmanned aerial systems can be used to detect the forest road surface damage with the difference in accuracy being up to 2 cm compared with the accuracy of the current tachymetric methods. Based on the results we can conclude that the used method is appropriate for detailed monitoring of the condition of the asphalt wearing course of forest roads and allows for a precise and objective localization and quantification of damage.

Development and Validity of Western University's On-Road Assessment.

Although used across North America, many on-road studies do not explicitly document the content and metrics of on-road courses and accompanying assessments. This article discusses the development of the University of Western Ontario's on-road course, and elucidates the validity of its accompanying on-road assessment. We identified main components for developing an on-road course and used measurement theory to establish face, content, and initial construct validity. Five adult volunteer drivers and 30 drivers with multiple sclerosis participated in the study. The road course had face and content validity, representing 100% of roadway components determined through a content validity matrix and index. The known-groups method showed that debilitated drivers (vs. not debilitated), made more driving errors ( W = 463.50, p = .03), and failed the on-road course, indicating preliminary construct validity of the on-road assessment. This research guides and empirically supports a process for developing a road course and its assessment.

IMPROVEMENT OF LOOSE GRANULAR SOIL BY USING GEOGRID REINFORCEMENT

There are several uses of granular soils in civil engineering works such as but not limited to under foundations structures, subbase course of roads, unpaved roads and soil embankments. This research attempts to overcome the problems of low-quality (by means of strength) of granular soil by enhancing California Bearing Ratio (CBR) test by utilizing geogrid. The research aim's to investigate the potential benefits of using the geogrid to improve CBR of granular soil. The results of tests showed that the granular soil under study was inferior than the materials comply on class C of Iraqi specifications for granular soil material. On the other hand, using of geogrid type Tensar SS2 at 0.15H (where H the total thickness of granular material samples) improves extremely the CBR value of the granular soil as it is increased by about three times in comparison with untreated soil.

Electrophysiological assessment of driving pleasure and difficulty using a task-irrelevant probe technique

The amplitude of event-related brain potentials (ERPs) elicited by task-irrelevant auditory probes decreases when more attentional resources are allocated to a visual task. This task-irrelevant probe technique is considered to be useful in assessing the degree of interest in a visual task, as well as task difficulty. The present study examined the amplitude of the N1 and P2 components elicited by task-irrelevant auditory probes during a driving task in a simulated environment. The analysis of ERPs showed that the N1 amplitude decreased when participants drove on the road course that had more frequent and sharper curves, whereas the P2 amplitude decreased when the road contained sharper curves, irrespective of curve frequency. Subjective ratings of driving pleasure and difficulty showed the same variation patterns as the N1 and P2 amplitudes, respectively. These results suggest that use of the task-irrelevant probe technique can assess the degree of driving pleasure and difficulty separately.

Relikty przebiegu sieci drożnej bliskich przedmieść Torunia z końca XVIII wieku we współczesnej topografii miasta na podstawie analizy GIS

The article presents research that aimed to identify the remains of the road network of Toruń’s close suburbs from the late 18th century on the contemporary system of city streets based on GIS (Geographic Information Systems) analysis. The study area included the close suburbs of the Old Town of Toruń. The source materials were two plans of Toruń and its suburbs from the late 18th century and a contemporary geodetic plan of the town. The historical plans did not meet cartometric requirements. Therefore, an essential condition for achieving the objective of the study was to make them precisely match the contemporary geodetic plan of the town (constituting the reference layer). For this purpose, a rubber sheeting type transformation was applied, which increased the cartometric value of the analysed plans and enabled the authors to acquire qualitative and quantitative data from them. In addition, a certain margin of error was assumed in the potential compatibility of the course of the contemporary streets of Toruń in relation to the roads of suburbs of the 18th century town, which was realized based on the buffer function. The results of the analysis show that the contemporary streets of the close suburbs of the Old Town of Toruń correspond to approximately 40% of the length of roads from the late 18th century, as depicted on the analysed plans. In the authors’ opinion, in the contemporary topography of the close suburbs of the Old Town of Toruń, many streets or their sections can be considered the remains of the course of the 18th-century roads with a high probability, and even, which results from historians’ research, the course of medieval ones. This is despite centuries of transformation of the town’s suburbs that were related primarily to the construction of fortifications from the 17th to the 19th century.

The Orientation of a Street of Turin along the Major Southern Moonrise Direction

This paper is showing that a street of Torino has an orientation which is coincident to the major southern direction of moonrise. This street, Via Po, was designed by the architect Amedeo di Castellamonte, following the course of an old road of Roman times. It is possible that the architect had rectified the ancient course to obtain such a precise alignment, or that it was already present in the Roman road. This astronomical alignment could be the origin of a local story concerning the church of the Gran Madre.

Statistical process control for autocorrelated data on grid

Assumptions of normality and independence are the key assumptions required in the development and use of control charts. The assumption of independence is hard to justify in many experimental data. The control charts for sample mean and sample standard deviation are obtained in this article when the observations are obtained over a grid on a two-dimensional surface. It is assumed that the observations follow a first order autoregressive process in both the directions. The results are applied to road pavement data on road course thickness observed on a two dimensional grid. The results from a simulation study are presented for the comparison of modified and unmodified control limits.

Grid-Based Multi-Road-Course Estimation Using Motion Planning

Knowing the course of the road, together with the corresponding road boundaries is an essential component of many advanced driver-assistance systems and of autonomous vehicles. This work presents an indirect grid-based approach for road course estimation. Due to the grid representation, it is independent of specific features or particular sensors and is able to handle continuous as well as sparse road boundaries of arbitrary shape. Furthermore, the number of road courses in the scene is determined to detect road junctions and forks in the road, and the boundaries of each road course are individually estimated. The approach is based on local path planning and path clustering to find the principal moving directions through the environment. They separate the boundaries and are used for their extraction. The set of local paths and principal moving directions is reduced with approximate knowledge of the road velocity paired with system constraints, and validation and tracking assure the required robustness. Experimental results from autonomous navigation of a vehicle through an unmapped road construction site as well as quantitative evaluations demonstrate the performance of the method.

The Road to Novelty II: Recognition and the Economics of Symmetries

This series of articles entitled The Road to Novelty offers a new access to the phenomena of newness, knowledge, pattern recognition, semantics and historical time using the concept of symmetries. According to Part I we must first create a space equipped with an appropriate terrain of concepts and knowledge (Space-Forming) before being able to specify a path for a road that directs us towards Novelty. Both, the conceptual spatial structure on the one hand and the embedded road course on the other, require different information concepts for dealing with them. While we can easily capture everything that can be localized within a spatial structure by using the concept of Bits & Bytes, we have yet to introduce a new category of information based on the concept of symmetries to address the spatial structure itself. This new category will enable us to access the semantic content of concepts and, in economic terms, to also navigate our environment in a superior, complexity-reducing way. In relation to each other, these two information-theoretical concepts behave in ways that are mutually dual and complementary. Also, with respect to time, they interact in a complementary manner by generating different aspects of irreversibility, that is to say, different aspects of the historical aspect of time.

동적계획법을 이용한 자작 하이브리드 자동차의 용량 매칭

Article history: Generally, the fuel economy of hybrid electric vehicle (HEV) is effected by the size of each component. In this study the fuel economy for HEV of our own making is evaluated using backward simulator, where dynamic programming is applied. In a competition, the vehicle is running through the road course that includes many speed bumps and steep grade. Therefore, the new driving cycle including road grade is developed for the simulation. The backward simulator is also developed through modeling each component. A performance map of engine and motor for component sizing is made from the existing engine map and motor map adapted to the HEV of our own making. For optimal component sizing, the feasible region is defined by restricting the power range of power sources. Optimal component size for best fuel economy is obtained within the feasible region through the backward simulation.

Driver drowsiness detection based on non-intrusive metrics considering individual specifics

ObjectivesDrowsy driving is a serious highway safety problem. If drivers could be warned before they became too drowsy to drive safely, some drowsiness-related crashes could be prevented. The presentation of timely warnings, however, depends on reliable detection. To date, the effectiveness of drowsiness detection methods has been limited by their failure to consider individual differences. The present study sought to develop a drowsiness detection model that accommodates the varying individual effects of drowsiness on driving performance. MethodsNineteen driving behavior variables and four eye feature variables were measured as participants drove a fixed road course in a high fidelity motion-based driving simulator after having worked an 8-h night shift. During the test, participants were asked to report their drowsiness level using the Karolinska Sleepiness Scale at the midpoint of each of the six rounds through the road course. A multilevel ordered logit (MOL) model, an ordered logit model, and an artificial neural network model were used to determine drowsiness. ResultsThe MOL had the highest drowsiness detection accuracy, which shows that consideration of individual differences improves the models’ ability to detect drowsiness. According to the results, percentage of eyelid closure, average pupil diameter, standard deviation of lateral position and steering wheel reversals was the most important of the 23 variables. ConclusionThe consideration of individual differences on a drowsiness detection model would increase the accuracy of the model's detection accuracy.

Monocular Road Terrain Detection by Combining Visual and Spatial Information

For future driver assistance systems and autonomous vehicles, the road course, i.e., the width and shape of the driving path, is an important source of information. In this paper, we introduce a new hierarchical two-stage approach for learning the spatial layout of road scenes. In the first stage, base classifiers analyze the local visual properties of patches extracted from monocular camera images and provide metric confidence maps. We use classifiers for road appearance, boundary appearance, and lane-marking appearance. The core of the proposed approach is the computation of SPatial RAY (SPRAY) features from each metric confidence map in the second stage. A boosting classifier selecting discriminative SPRAY features can be trained for different types of road terrain and allows capturing the local visual properties together with their spatial layout in the scene. In this paper, the extraction of road area and ego-lane on inner-city video streams is demonstrated. In particular, the detection of the ego-lane is a challenging semantic segmentation task showing the power of SPRAY features, because on a local appearance level, the ego-lane is not distinguishable from other lanes. We have evaluated our approach operating at 20 Hz on a graphics processing unit on a publicly available data set, demonstrating the performance on a variety of road types and weather conditions.

INVESTIGATION OF ASPHALT PAVEMENT WITH ADDED CRUMB RUBBER

Waste tires must be recycled in environmentally safe ways that meet civil engineering concerns while fulfilling standards for construction materials. Used tires can be processed into rubber powders with particle sizes of 0–2 mm, a suitable fine aggregate for mixing into road pavements. We tested asphalt mixtures with rubber added using the dry method, comparing their properties with a traditional mixture. We tested asphalt–rubber mixtures with rubber incorporated at either ambient temperature or preheated. Rubberized and traditional asphaltconcretes compared well in void content, indirect tensile strength ratio, rut depth, and wheel-track slope. After optimizing the rubber content added, we laid an experimental road course with the asphalt–rubber mixture.

Heavy Truck Driver Workload Investigation

ABSTRACT Driver workload is of growing interest in the automotive society, since the number of in-vehicle technologies and vehicles on the road grows. Operational and environmental factors impact the driver's ability to negotiate a chosen course and place heavy demands on the driver in terms of mental and physical capacity. A key component of the driver's operating environment is the vehicle. In this research, the impact of various tire configurations, for example, dual and wide based, for a Class 8 tractor–semitrailer combination vehicle on driver workload performance is presented. Driver workload performance is assessed during four maneuvers: 60 m radius steady state circle, 120 m radius steady state circle, road course, and North Atlantic Treaty Organization emergency lane change maneuver. Surface electromyography (sEMG) electrodes were placed on the left and right wrist flexors (flexor carpi ulnaris) and right wrist extensors (extensor carpi ulnaris) in order to capture muscle activity during all maneuvers. Peak and integrated values of sEMG are calculated to obtain metrics of driver workload. Results of the study show distinct separation of muscle activity for each tire configuration. Differences in driving techniques were also identified based on the dominant hand of the driver and orientation of the maneuver, that is, clockwise or counterclockwise.

Role of aggregate petrography in micro-texture retention of greywacke surfacing aggregate

Aggregates provide more than 90% by weight of bituminous wearing courses that make up the road surface. This paper looked at the role of aggregate petrography towards the micro-texture retention of surfacing aggregate, through resistance to polishing under simulated trafficking conditions using the polished stone value test. For greywacke aggregate it was found that mineral composition, along with the shape of hard mineral grains within a softer clay matrix, had an effect on how aggregate surface polishes under trafficking. This impacts road surface performance, particularly skid resistance, which is a crucial safety aspect of a road surface course.

Seeing pedestrians at night: effect of driver age and visual abilities.

To quantify the effects of driver age on night-time pedestrian conspicuity, and to determine whether individual differences in visual performance can predict drivers' ability to recognise pedestrians at night. Participants were 32 visually normal drivers (20 younger: M=24.4years±6.4years; 12 older: M=72.0years±5.0years). Visual performance was measured in a laboratory-based testing session including visual acuity, contrast sensitivity, motion sensitivity and the useful field of view. Night-time pedestrian recognition distances were recorded while participants drove an instrumented vehicle along a closed road course at night; to increase the workload of drivers, auditory and visual distracter tasks were presented for some of the laps. Pedestrians walked in place, sideways to the oncoming vehicles, and wore either a standard high visibility reflective vest or reflective tape positioned on the movable joints (biological motion). Driver age and pedestrian clothing significantly (p<0.05) affected the distance at which the drivers first responded to the pedestrians. Older drivers recognised pedestrians at approximately half the distance of the younger drivers and pedestrians were recognised more often and at longer distances when they wore a biological motion reflective clothing configuration than when they wore a reflective vest. Motion sensitivity was an independent predictor of pedestrian recognition distance, even when controlling for driver age. The night-time pedestrian recognition capacity of older drivers was significantly worse than that of younger drivers. The distance at which drivers first recognised pedestrians at night was best predicted by a test of motion sensitivity.