Polymerization of 2,5-diformylfuran with two primary amines was carried out in acetonitrile and ethanol at room temperature. The reaction was characterized using a combination of mass spectroscopy and NMR spectroscopy, which revealed the clean formation of the imine -CH N− functional group. Although some cyclic products were detected from mass spectroscopy, the ring size was limited to products that have the −CH N− group only in anti-geometry. The furan Schiff bases exhibit good thermal stability. While mass spectra evidenced oligomers of different lengths, cross-polarization magic angle spinning 13 C NMR spectra of the insoluble polymer revealed the linear structure as proposed.

Civil Engineers ; edited by Jin Zhang … [et al.]. v. cm. Includes bibliographical references and index. ISBN 978-0-7844-1260-2 1. Transportation engineering--Congresses. 2. Business logistics--Congresses. I. Zhang, Jin, Prof. II. American Society of Civil Engineers. III. Xi nan jiao tong da xue (China) IV.

This paper presents an unconventional approach for work-zone bottleneck traffic control through integrating the dynamic late merge with a merge metering via wireless communication at the downstream taper area of a work zone, termed as Dynamic Merge Metering Traffic Control System (DMM-Tracs). The architecture and communication system for the DMM-Tracs, including system components, communication technologies and operation mechanism, are introduced. With this system, the merge metering control will be activated depending on the volume detected at an upstream location of the work-zone bottleneck. If the thresholds of control parameters are met, a merge metering signal installed at the taper area will be activated and approaching vehicles will be informed of the metering situation through flashing signage or changeable message sign installed in the advance areas of the work zone. To reduce enforced merges and potentials of merge conflicts, the control scheme will be adjusted on the real-time basis depending on the detected traffic conditions. This potentially increases the efficiency with which the traffic is discharged into the open lane inside the work zone. A portable controller is the "brain" of the DMM-Tracs to receive data from detectors, process the data, and control the merge metering signal via wireless communications. The efficacy of the DMM-Tracs is evaluated via a microsimulation test bed with the state-of-the-art microscopic simulation software VISSIM. Meanwhile, the volume threshold values are also determined via the simulation. The simulation results indicate that higher lane-closure percentage of the bottleneck, more applicable the DMM-Tracs.

The rapidly improving autonomous vehicle (AV) technology will have a significant impact on traffic safety and efficiency. This study introduces a game-theory-based priority control algorithm for autonomous vehicles to improve intersection safety and efficiency with mixed traffic. By using vehicle-to-infrastructure (V2I) communications, this model allows an AV to exchange information with the roadside units (RSU) to support the decision making of whether an ordinary vehicle (OV) or an AV should pass the intersection first. The safety of vehicles is taken in different stages of decisions to assure collision-free intersection operations. Two different mathematical models have been developed, where model one is for an AV/AV situation and model two is when an AV meets an OV. A simulation model was developed to implement the algorithm and compare the performance of each model with the conventional traffic control at a four-legged signalized intersection and at a roundabout. Three levels of traffic volume and speed combinations were tested in the simulation. The results show significant reductions in delay for both cases; for case (I), AV/AV model, a 65% reduction compared to a roundabout and 84% compared to a four-legged signalized intersection, and for case (II), AV/OV model, the reduction is 30% and 89%, respectively.

The rapid growth in population and the increase in the number of vehicles on the road have resulted in severe traffic congestion over the last two decades. However, intersections, where different flows intersect, are among the major cause of traffic congestion besides bottlenecks. Past decades have seen major technological advancements in road vehicles aimed at making vehicles traveling securely and comfortably. Current connected and automated vehicles (CAV) are packed with lane-keeping assistance and adaptive cruise control to ensure that vehicles do not collide and reduce traffic congestion. In this research, we developed a control algorithm that utilizes CAVs to help generate additional usable gaps for the minor road vehicles to enter the intersection without affecting the mainline traffic flow. Simulation results showed that the delay and queue length of the minor road approach is minimized without causing a significant delay to the mainline. The minor road delay was reduced by 72% when the percentage of CAVs on the major road is 70% compared to the benchmark with no CAVs on the major road.

Circular intersections have been used in transportation systems since the 1900s. Three types of circular intersections have been used in the United States: traffic circles, rotaries and roundabouts. While the use of traffic circles and rotaries in recent decades was found to have resulted in high crash rates, safety issues have been mitigated for roundabouts through the use of improved geometric designs. Nevertheless, all three types of circular intersections face capacity problems during periods of high traffic volume, resulting in long queues and delays. Signal metering was introduced to reduce long queues and delays on the dominant approaches to circular intersections by stopping the flow of traffic from other approaches. This methodology was found to ease congestion for circular intersections with historically high traffic volumes. However, most signal metering at those intersections employ fixed signal timing, in which the metering rate is not responsive to changes in traffic condition. This study investigates the performance of an adaptive metering system for circular intersections. The system was implemented on a real traffic circle having high and unbalanced volumes. The model was calibrated, and a case study was simulated for peak-hour traffic conditions. Using the PTV VISSIM application programming interface, the algorithm was tested and the performance of the system was compared to the current intersection operation. The results showed that adaptive metering can significantly reduce delays and queues at a traffic circle. This preliminary study can be a useful reference for the development of prioritycontrolled circular intersections.

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Gaming or gambling has a crucial and distinctive place in the Australian culture. Many Australians are proud of their reputation as a nation of people who will "bet on two flies on the wall". This study attempts to explore the popularity of gaming in Australia and its relationship with the Australian national identity. Three representative elements in Australian national identity, egalitarianism, fatalism and mateship are discussed together with gaming, revealing a result that those cultural factors are all embodied in gaming. The study focuses on the cultural factors integrated in the gaming activities, using cultural elements to explain the significant social phenomenon.