Empirical Examination of Passing Lane Operational Benefits on Rural Two-Lane Highways

This paper presents an empirical investigation into the operational benefits of passing lanes on rural two-lane highways. Two study sites in the state of Montana were used in this investigation. Performance was examined at a single location upstream and multiple locations downstream of the passing lane at each study site. Using percent followers as a performance measure, operational benefits right after the passing lane ranged between 33% and 42% at one study site and 12% to 19% at the other study site under prevalent traffic levels. Study results also suggest that operational benefits persist for a remarkable distance beyond the end of the passing lane

Quantitative Study of the Evaluation of the Activity of Immune Cells in the Spleen of Diseased Mice with Cancer by Soft Laser

Background: Little informations have been published about the active role of soft laser in stimulation the immune cells, so, our work was conducted to examine experimentally the capacity of the immune cells such as macrophages of the spleen in reducing the tumor size of diseased mice with mammary gland carcinoma by soft laser.Materials and Methods: Fourty healthy female Swiss albino mice aged two months (weighing 45-48g) were used in the present experimental work. They were divided into five groups of six mice each. All the animals inoculated with mammary gland carcinoma. After successful inoculation, the animals were anaesthetized and irradiated with laser for 25 minutes with different time intervals and for ten days. The tumor size was measured before and after irradiation by vernier, daily, starting from tumor appearance until the last day of the experiment (10days). Sections of spleen were prepared and examined for histopathological study by light microscope.Results: The present experimental work showed reduction in tumor size of diseased mice with carcinoma irradiated with laser with the increasing of time interval for each experimental group of mice when compared to the tumor size of diseased mice with carcinoma not irradiated with laser. The histological examinations of the sections of the spleen of the diseased mice with carcinoma irradiated with laser showed abundant histological alterations in the structure of the macrophages such as increased size and multiplication of the nucleus when compared to the macrophages of the spleen of the diseased mice with carcinoma not irradiated with laser.Conclusion: The present experimental work proved that soft laser played an important role in activation the immune cells such as macrophages of the spleen and then decreased the tumor size of diseased mice with carcinoma and caused marked histological alterations in the structure of the macrophage due to laser action. Keywords: Soft laser, Laser in medicine

Prioritization Scheme for Proposed Road Weather Information System Sites: Montana Case Study

A model for prioritization of new proposed environmental sensor station (ESS) sites is developed and presented in this paper. The model assesses the overall merit (OM) of a proposed ESS site as part of a Road Weather Information System (RWIS) using weather, traffic, and safety data among other variables. The purpose of the proposed model is to help in selecting optimum sites for new ESS locations, which is important in guiding RWIS system expansion. Inputs to the OM model include weather index (WI), traffic index (TI), crash index, geographic coverage, and opportunistic factors. The WI at a proposed site is determined using multiple indicators of weather severity and variability. The crash index, another major input to the OM model, incorporates crash rate along the route and the percentage of weather-related crashes over the analysis period. The TI, in turn, reflects the amount of travel on the highway network in the area surrounding the proposed ESS site. The fourth input to the merit model accounts for the ESS existing coverage in the area where the proposed site is located, while the fifth and last input is concerned with the availability and ease of access to power and communications. Model coefficients are represented by weights that reflect the contribution of each input (variable) to the OM of the ESS site. Those weights are user-specified and should be selected to reflect the agency preferences and priorities. The application of the proposed merit model on sample sites in Montana demonstrated the utility of the model in ranking candidate sites using data readily available to highway agencies

Characterization of cell phone use while driving in Jordan

A substantial body of research has shown that the use of cell phones while driving can impair driving performance thus representing a relevant traffic safety issue. The conducted studies have indicated that with an increase in general cell phone use, phoning while driving has also grown. For around 80% of Jordan's population that own cell phones, phoning while driving has become a legitimate concern for potential safety hazards. In order to effectively target interventions towards the drivers using cell phones while driving, information about the characteristics of these respondents is needed. The present study investigates the extent of cell phone use on Jordan's roads and the characteristics of drivers who use cell phones while driving. The data was collected using a questionnaire survey to examine the relationship between phoning while driving and driver demographics, driving experience and exposure and characteristics of users. Among all participants, the study demonstrated that those who reported the use of hands‐free devices tended to use the cell phone more often and for a longer duration of time. Further, male drivers tended to use the cell phone while driving more frequently and for longer duration compared with female drivers. In regards to pulling off the road while using the cell phone, the study found this practice to be more prevalent among females, older drivers and more educated drivers. The study has also revealed other findings that are important for characterizing the trend towards using the cell phone while driving in Jordan. First published online: 10 Feb 201

Investigation of Performance and Lane Utilization within a Passing Lane on a Two Lane Rural Highway

Abstract: An investigation into platooning and passing maneuvers within a passing lane section on a rural two-lane, two-way highway was considered in this study. The study site was located on US Highway 287 between the town of Townsend and the City of Helena in the state of Montana. Traffic volumes at study site, while considered relatively low, were typical on two-lane highways in many rural states. Per-lane analysis of performance measures and lane utilization (volume split) were used to indirectly examine passing maneuvers and lane changing at successive locations within the passing lane section. For the case study site, it was evident that traffic performance became relatively stable beyond half a mile into the passing lane for the traffic volumes investigated. Therefore, results strongly suggested that most passing maneuvers already took place before the 0.5-mile station and that the actual passing lane length was well beyond the optimal length required for breaking up platoons and improving performance

Two-Lane Highways: Indispensable Rural Mobility

Two-lane highways refer to roadways consisting of two lanes in the cross section, one for each direction of travel. Occasionally, passing lanes may be added to one or two sides of the roadway extending the cross section to three or four lanes at those locations. In this entry, two-lane highways strictly refer to roads in rural areas meeting the previous definition and do not include urban and suburban streets

A New Approach for Identifying Safety Improvement Sites on Rural Highways: A Validation Study

The research presented in this paper examines a new proposed approach for identifying safety improvement sites on rural highways. Unlike conventional approaches, the proposed approach does not require crash history, but rather utilizes classified variables for traffic volume, geometric features, and roadside characteristics that do not require access to exact data or extensive technical expertise. The research validates the performance of the proposed approach using field data from a large sample of rural two-lane highway segments in the state of Oregon including traffic, roadway, and crash data. A mathematical model for the prediction of the EB expected number of crashes using multivariate regression analysis is developed and used as the network screening criterion. The model’s independent variables include roadway geometry, roadside characteristics, and traffic exposure, while the dependent variable is the EB expected number of crashes. Using observed crash history as a reference, the performance of the proposed approach was compared to two of the well-established methods in practice, namely, the Empirical Bayes (EB) and the potential for safety improvement (PSI) methods. The study results suggest that by using crash density for highway segments, the performance of the proposed method was lower than that of the EB and PSI methods. This is despite the high R-square value of the predictive model used in the proposed method. However, when using crash frequencies for highway segments, the performance of the proposed method was found comparable to the well-established EB and PSI methods

Empirical Examination of Passing Lane Operational Benefits on Rural Two‐Lane Highways

This paper presents an empirical investigation into the operational benefits of passing lanes on rural two-lane highways. Two study sites in the state of Montana were used in this investigation. Performance was examined at a single location upstream and multiple locations downstream of the passing lane at each study site. Using percent followers as a performance measure, operational benefits right after the passing lane ranged between 33% and 42% at one study site and 12% to 19% at the other study site under prevalent traffic levels. Study results also suggest that operational benefits persist for a remarkable distance beyond the end of the passing lane