Traffic Speed Report No. 117 : Interim Report

How early hydrogen fuel cell vehicle adopters geographically evaluate a network of refueling stations in California

Control of movement in artificial molecular machines relies on the formation of out‐of‐equilibrium states that can subsequently interconvert to their ground states. However, a detailed description of molecular machines that are out of equilibrium is a challenge because they are often too short‐lived to be characterized. Herein, the synthesis of two cyclobis(paraquat‐p‐phenylene) [2]rotaxanes that incorporate a redox‐active monopyrrolotetrathiafulvalene unit as the primary station and either a hydroquinone or a xylyl moiety as the secondary station is described. It is shown that the bistable [2]rotaxanes can be pushed out of equilibrium by an oxidation/reduction cycle and since a steric barrier is located between the two stations, the out‐of‐equilibrium states of the [2]rotaxanes can be physically isolated as solids. This allows to make detailed spectroscopic and electrochemical investigations of the [2]rotaxanes in both the di‐oxidized and un‐oxidized states. The outcome of the studies shows that the replacement of the secondary hydroquinone station with a xylyl station has no impact on the thermodynamic properties but has a significant effect on the kinetic properties of the [2]rotaxanes illustrating that the nature of the secondary station can be used to control the speed of [2]rotaxane‐based molecular machines.

This report documents the May-August 1987 study of free flow automobile and truck speeds on tangent, level and dry sections of rural interstate, rural four-lane, rural two-lane and urban interstate highways in Indiana. The results of this report show that all types of vehicles, on all types of Indiana highways, had an average free flow speed of 59.3 mph in 1987. This indicates an increase of 0.7 mph from 1986. If the two urban interstates are excluded, the average speed on all types of rural highways in Indiana becomes 59.1 mph in 1987. This also represents an increase of 0.7 mph from 1986. All types of vehicles on rural interstate highways had an average speed of 62.3 mph, which is up by 2.2 mph from 1986. This is not unexpected, due to the implementation of the 65 mph speed limit on Indiana rural interstate highways effective June 1, 1987.

Non-Indiana 57.7 56.9All Passenger Cars 55.9 56.5 85 Percentile (all) 60.6 61.0 Trucks : Less than 5000 lbs.54.8 56.2 5000 lbs.or more 55.6 54

The IEEE 1609.4 standard has been proposed to provide multi-channel operations in wireless access for vehicular environments (WAVE), where all the channels are periodically synchronized into control and service intervals. The communication device in each vehicle will stay at the control channel for negotiation and contention during the control interval, and thereafter switch to one of the service channels for data transmission in the service interval. The inefficiency of WAVE system comes from the fact that half of the time intervals of the service channels remain idle since all the stations are performing message contention within the control channel. In this paper, the cognitive radio-enabled multi-channel access (CREM) protocol is proposed to increase the channel utilization of IEEE 1609.4 standard. Based on the concept of cognitive radio, the vehicular stations are categorized into primary stations with safety-related messages and secondary stations with non-safety information to be delivered. Prioritized channel access is designed in the proposed CREM scheme in order to increase the transmission opportunity of primary stations. Moreover, extended time intervals are granted for primary stations to ensure reliability for data transmission. The enhanced CREM (CREM-E) protocol is proposed to further opportunistically increase the channel utilization of secondary stations. Simulation results show that the proposed CREM-E scheme outperforms the existing IEEE 1609.4 protocol with enhanced channel utilization and smaller waiting time intervals.

Traffic Speed Report No. 108 : Interim Report

Rural Interstate Highways *RI-21 (1-69) First bridge south of junction with S.R. 18 [Had to move location due to construction. Location taken was 3.4 miles north of S.R. 18 and near 68 mile marker.] *RI-6

Shrublands of Temperate Europe

Considerable interest has developed of late in the problem of wildlife mortality on our public highways (see Dickerson, L. M., the JOURNAL OF WILDLIFE MANAGEMENT, 1939, vol. 3, p. 104). In an attempt to gain some measure of the losses on the highways of Texas, I kept daily records (except for July and August) from February 1, 1938, to January 31, 1939, of mammals run down by motorists on the six miles of concrete highway between College Station and Bryan in Brazos County. Traffic on this section of highway is heavier than average, increasing the hazard to wildlife, but this factor is compensated for in part by the relative scarcity of most kinds of mammals in this section of the state. I consider my data as probably slightly less than average for a similarly constructed six-mile section of highway in some other part in Texas, as, for example, the TransPecos region. On unimproved highways, of course, the losses would tend to be much less, for it is common knowledge that the rate of mortality to wildlife, and man as well, increases directly with the degree to which a highway is improved for rapid transit. Disregarding the months of July and August in which no data were recorded, the average monthly loss of mammals was 5, or nearly 10 per mile-year. If my data be nearly average for similar sections of fast highway in other parts of the state, the total number of mammals (not counting man) killed each year on the 15,675 miles of hard surfaced highways in Texas is 156,750. If w assume that a reduction of average speed on the highway from 50 m.p.h. to 30 m.p.h. will reduce highway mortality of wildlife from 10 a mile-year to, say, 4, the yearly loss on the 5,790 miles of graveled and unimproved roads in the State would amount to 23,160. Add this to the figure derived for the fast highways, and we get a total of 179,910. This figure is for mammals alone. No r cord was kept of the birds, reptiles, and amphibians run down by motorist , but I gained the impression that during the ten months of observation the loss of birdlife was only about onef fth that of mammals; reptiles, however, especially the painted terrapin (Terrapene ornata), fared much worse than did the mammals.

Data link-control performance: Results comparing HDLC operational modes

This paper presents an open source implementation for a data-link layer protocol specified in IEC 60870, protocol specification for telecontrol networks. It has been tested over LEON an embedded system with a Linux based operating system. Protocol engineering methods have been used in order to implement the protocol. The standard is in natural language so a formal language is needed to describe its behavior. A prototype has also been created to simulate the protocol behavior. The protocol has been tested on a real environment, using PCs and LEON as primary and secondary stations, and different physical layers, serial cable, radio frequency and GSM.

Abstract. Hundreds of wildfires in Northern California were sparked by lightning during the summer of 2008, resulting in downwind smoke for the months of June and July. Comparisons are reported for aerosol optics measurements in Reno, Nevada made during the very smoky month of July and the relatively clean month of August. Photoacoustic instruments equipped with integrating nephelometers were used to measure aerosol light scattering and absorption coefficients at wavelengths of 405 nm and 870 nm, revealing a strong variation of aerosol light absorption with wavelength. Insight on fuels burned is gleaned from comparison of Ångström exponents of absorption (AEA) versus single scattering albedo (SSA) of the ambient measurements with laboratory biomass smoke measurements for many fuels. Measurements during the month of August, which were largely unaffected by fire smoke, exhibit surprisingly low AEA for aerosol light absorption when the SSA is highest, again likely as a consequence of the underappreciated wavelength dependence of aerosol light absorption by particles coated with non-absorbing organic and inorganic matter. Coated sphere calculations were used to show that AEA as large as 1.6 are possible for wood smoke even with non-absorbing organic coatings on black carbon cores, suggesting care be exercised when diagnosing AEA.

In Canada, rural-based family medicine residency programs were established largely in response to a shortage of rural physicians and the perception that urban-based training programs were not meeting the needs of rural populations. Examinations of practice patterns of physicians trained in rural and urban programs are lacking. The purpose of this study was to compare the scope of practice of family medicine graduates who completed a rural versus an urban residency program, by practice location. This was a cross-sectional, mail-out, questionnaire survey of 651 graduates who had completed the family medicine residency program at the University of Alberta or the University of Calgary, Alberta, Canada during 2006-2011. Rural program graduates lived and trained in regional settings and spent a considerable amount of time in smaller rural and remote communities for their clinical experience. The training of urban program graduates was primarily based in large urban settings and family medicine clinical experience was based in the community. Practice location (rural, urban) was classified by population size of the town/city at which physicians practiced. Scope of practice was ascertained through four domains of care: types of care, clinical procedures, practice settings and specific populations. Items within each domain were rated on a five-point scale (1='not part of practice', 5='element of core practice'). Mean rating scores for items in the domains of care were compared between urban and rural program graduates using ANOVA. A total of 307 (47.2%) graduates responded to the survey, of whom 173 were categorized as urban program graduates and 59 as rural program graduates. Overall, rural program graduates exhibited a broader scope of practice in providing postnatal care, intrapartum care/deliveries, palliative care, office-based and in-hospital clinical procedures, emergency care, in-hospital care, home visits, long-term care, and caring for rural and Aboriginal populations. Irrespective of program completed, those in a rural practice location had a broader scope of practice than those in urban practice. Urban and rural program graduates in rural locations tended to have a similar scope of practice. In urban locations, rural program graduates were more likely to include intrapartum care/deliveries as part of their clinical practice. Rural program graduates were more likely to practice in rural locations than urban program graduates. A combination of site of training (rural or urban program) and location of practice appear to work together to influence scope of practice of family physicians. A conceptual framework that summarizes the factors that have been reported to be associated with the scope of family practice is proposed.

Climate change and warming will potentially profoundly affect forest growth and yield. However, climate change is not only a threat but also an opportunity for tree species to be more productive or colonize new territories where previously they were fragmented or absent. European beech (Fagus sylvatica L.) is a dominant and significant tree species in European forests with a pronounced ability to grow on a great variety of sites and to form mixtures with other tree species due to its shade tolerance. So far, only a few studies have analysed its growth and reaction to changing climatic conditions outside its natural gradient in the north. The aim of this study was therefore to clarify the main growth patterns and tree ring formation characteristics of beech (outside their natural distribution) in mixed stands with Scots pine (Pinus sylvestris L.) The analyses were carried out in two-layered stands in the western part of Lithuania with tree-ring data measured on stem disks collected at 1 m height that were available from shelter-cut thinning activities in a number of forest stands in the region. Our results show that higher temperatures during the summer months of July and August generally inhibited the radial growth of beech under given site conditions. In contrast, warmer late-autumn and cooler early-winter periods together with warmer springs positively affected the radial increments. Above-average precipitation during the vegetation period contributed to the beech producing additional amounts of radial increments. The increasing temperature trends of the summer months and decreasing monthly amounts of precipitation during the vegetation period in recent decades tend to have adverse effects on the ecological conditions for beech growth and vitality in Lithuania. Despite these results, the European beech successfully grows in the sample region and has produced 200 m3 ha−1 in the analysed stands.

The Highway Capacity Manual prescribes level-of-service (LOS) criteria as a function of traffic density to categorize the operational conditions of both rural and urban freeway sections. This density-based level of service is ideally suited to the assessment of urban freeways when the performance must be optimized to meet high traffic demand. There is, however, some question as to whether density is the appropriate indicator of the quality of service on rural freeways, since drivers may think more in terms of psychological or emotional comfort for freeways, which generally serve long, high-speed trips and rarely experience more than moderate congestion levels. Three specific measures are examined that have at least an intuitive relationship to the concept of driver comfort: ( a) acceleration noise, which is a measure of the physical turbulence in the traffic stream; ( b) number and duration of cruise control applications, which could serve as a general indication of driver convenience or inconvenience; and ( c) percent time spent following, which is already accepted as the basis for determining the level of service on rural two-lane highways. The three candidate measures were estimated for a hypothetical section of rural freeway by simulation, using the CORSIM model. The kinematic relationships of individual vehicles within the traffic stream were estimated by postprocessing the simulation data for each second of operation. All of the measures considered in this study have conceptual appeal. All have produced interesting and potentially usable results with respect to their relationships to traffic volume. Although the simulation results are interesting, further studies focusing on driver opinions, behavior, or field measurements, or all three, would likely be necessary to support the development and recommendation of a specific set of LOS criteria that recognizes the differences between the urban and rural freeway driving environments.