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Based on the available energy sources, the electric vehicle (EV) cannot compete with the conventional vehicle in terms of driving range and initial cost. In the near future, the hybrid EV (HEV) is not only an interim solution for implementation of zero emission vehicles but a practical solution for commercialization of super-ultra-low-emission vehicles. This paper firstly presents an overview of latest HEVs, with emphasis on power management. Based on the power management strategy of the drive train, a new classification approach for HEVs is proposed. Hence, the corresponding system configurations are identified. The power flow control for various HEVs is also elaborated. Finally, the development trends of HEVs and EVs are delineated.

A new tangent energy-absorbing W-beam guardrail terminal that meets NCHRP Report 350 criteria has been developed. The terminal, designated the SKT-350, dissipates the energy of an encroaching vehicle by producing a series of plastic hinges in the W-beam as the terminal head is pushed down the guardrail. This energy-absorption concept allows for significantly lower dynamic forces on the encroaching vehicle, reducing the vehicle damage, the weight of the terminal head, the propensity for vehicle yaw and roll after impact, and the chances of buckling in the W-beam section. The energy required to move the head down the rail in this design is optimized for current criteria, but by modifying the bending geometry in the head, the average force to displace the head down the rail can be adjusted from values ranging from 11 to 60 kN (2,500 to 13,500 lb), meaning that the system can be easily modified to meet any future changes in safety performance standards. In addition to these important safety advantages, the terminal incorporates a unique cable anchor bracket that closely resembles a breakaway cable terminal anchor and a novel foundation tube design that facilitates the removal of broken posts during repair. Combining the features of reduced forces and head weight, a simple cable box, and more economical soil tubes allows the system to offer the advantages of both reduced cost and improved performance.

The objective of this research was to characterize the second-by-second driving style of older drivers to account accurately for differences in lead-vehicle operations for different subgroups of drivers. The project focused on differences by age and used field data collected with in-vehicle instrumentation on a predefined route. The sample set included 19 individuals older than age 70 and 16 individuals between the ages of 21 and 35 years. Trends and differences in unconstrained speed and acceleration noise— including interactions with intersection departures, posted speed limits, grade, and horizontal curvature—were explored. The speeds of younger drivers were up to 3 mph greater than those of older drivers; variations were also attributable to geometric roadway characteristics. Most notably, the speed of younger drivers was influenced 64.5% more than the speed of older drivers by the curvature change rate in 35 mph zones. Older drivers were influenced 87% more than younger drivers by grade in 25 mph zones. Results reinforced the importance and feasibility of accounting for driver style in traffic simulation and emissions modeling and emphasized that age and geometric features were valuable factors for defining typology. Large robust data sets of driving behavior are needed to calibrate models of lead-vehicle behavior.

The city of Baltimore, Maryland, is now served by one heavy and one light rail line in addition to commuter rail service to Washington, D.C. However, the lines do not share any common stations and do not function as a network. The larger objective of this research was to evaluate ways in which the Baltimore transit system could be better integrated and contribute more to community well-being, environmental quality, and economic prosperity for all socioeconomic and racial and cultural groups. An underlying goal was to improve the mobility of a wider range of Baltimore residents so that their employment choices would not be limited by an underdeveloped transit system. This outcome was addressed in the context of the Intermodal Surface Transportation Efficiency Act of 1991, the Transportation Equity Act for the 21st Century, the Livable Communities Initiative, and the state of Maryland’s Smart Growth initiative. Only part of the larger agenda is presented here—the development of a community-based model for selecting and designing potential light rail line corridors in the larger system. The model used seven quality-of-life and livable community criteria—( a) potential to serve low-to moderate-income neighborhoods that have no direct access to public transportation (including bus access), ( b) high concentrations of employment opportunities along the route, ( c) highest number of intact commercial districts along the route, ( d) proximity to dense population centers (within a ¼-mi radius), ( e) proximity to numerous community social or cultural centers (including schools and churches), ( f) minimal physical environmental impacts, and ( g) the most potential to improve the pedestrian environment.

Accurately predicting the spatial distribution and charging demand of future electric vehicles (EVs) is vital to directing investment in charging infrastructure and planning policy interventions. To date, this expansion has been heavily concentrated in wealthy cities and suburbs, among commuters, and among households able to charge their vehicles at home. The expansion of EV ownership will include both changes in where the vehicles are owned and how they are used and charged. This paper demonstrates methods to predict where the expansion of EV ownership is most likely to occur under current market characteristics and allows for testing of scenarios of future characteristics. These methods are demonstrated with an analysis of California, U.S., using a scenario of 4 million battery electric vehicles (BEVs) and 1 million plug-in hybrid electric vehicles (PHEVs), to match the state’s goal of 5 million zero-emission vehicles by 2030. These projections are combined with a model for charging behavior to generate scenarios of demand for charging away from home under various fleet characteristics and identify areas of the state with the greatest need for infrastructure investment.

The growing market for plug-in electric vehicles (PEVs) features new models of battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs) with varying battery sizes and electric driving ranges. How are the various models being used in the real world? A common assumption in PEV impact analysis is that PEV owners will maximize their vehicle's utility by appropriately sizing the battery to their driving needs and by charging their vehicle as much as possible to recover the cost of the vehicle purchase. On the basis of these assumptions, a high correlation between PHEV owner use of the vehicle and the number of plug-in events is expected, and drivers of PHEVs with a small battery are expected to plug in more than do owners of vehicles with a larger battery and similar driving patterns. The assumptions presented are examined through a survey of more than 3,500 PEV owners conducted in California in May and June 2013. The online survey included extensive data on driving and charging behavior using web map questions. Owners of all PEV models on the market, including more than 600 Volts and 800 Prius Plug-Ins, were surveyed. The results show that small-battery PHEV electric vehicle miles traveled are lower than longer-range PHEV or BEV electric vehicle miles traveled not only because of battery size but also because of public charging availability and charging behavior. Higher electric-range PHEV and BEV drivers charge more often and report more charging opportunities in areas where smaller-battery PHEVs could not find chargers.

Abstract Marine policymakers are facing increasing calls to consider the resilience of communities that rely on coastal and marine ecosystem goods and services, and the resilience of natural systems themselves. These calls are in response to increasing threats to coastal communities from external factors such as coastal hazards, possibly associated with climate change, reductions in natural capital often caused by over-fishing and invasive species, and drivers that act to change local and regional economic conditions leading to changes in employment and inequality. However, most communities have had little experience in explicitly managing for resilience. Similarly, our understanding of the factors that make a natural or social system resilient is also somewhat limited. Furthermore, there is a lack of consensus-based definitions and performance measures for assessing resilience. These factors, along with other barriers, will need to be overcome before effective resilience-based management can be implemented.

A dynamic model for simulation of the transient interaction between radially oriented permanent magnet-type synchronous machines and their corresponding transistorized current source power conditioners is presented. Some key machine parameters used in this dynamic model were obtained from finite element field solutions. This dynamic model was used to obtain the transient interaction between a 15-hp samarium cobalt radially oriented permanent magnet electronically operated synchronous machine and its corresponding power conditioner. This machine was constructed for electric vehicle propulsion. Excellent correlation between various digitally simulated and actual test current and voltage waveforms, in various branches of the machine-conditioner network, has been achieved. These results are given. This modeling approach is applied to machines during the design stage, where the finite element modeling is the only way to obtain the necessary machine parameters for dynamic simulation. It is shown how such a combination of the computer-aided design tools can help in prevention of design mis-judgements that can prove costly to remedy once the hardware is in place. This is done through an actual design example of an additional machine being manufactured for electric propulsion applications.

With rapid growth in the number of personal motor vehicles, Indian cities have been facing increasing congestion and worsening air quality. Yet until early 2005 little attention was paid to this problem, and remedial measures were focused largely on overpasses and new roadway capacity. Only Delhi, Calcutta, and Chennai had built functioning metro rail systems. However, by the second half of 2006, barely a year and a half later, the situation changed considerably, and public transport became the focus of attention in most large and medium-sized cities. This paper looks at the national initiatives that helped bring about those changes. The adoption of a national urban transport policy along with the launching of a national urban renewal mission with a sizable commitment of funds helped focus attention on improving public transportation. These were supplemented by a series of well-conceived and -planned initiatives, again led by the national government, to generate more widespread awareness of urban mobility problems and how they could be successfully addressed. The results were visible in a mere 18 months, by which time several cities had already formulated plans for significantly improved public transport and the first incremental phase of what will be India's first bus rapid transit system had become operational.