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This paper presents an integrated vehicle model to simulate simultaneously the driver, powertrains, chassis, body, road condition, vehicle dynamics and the Active Suspension (AS) system with/without an energy harvesting module. The developed model is used to investigate the ride comfort and influences of energy harvesting AS system on the total energy consumption of battery Electric Vehicles (EVs) relative to EVs with a passive suspension system. Preliminary simulation results show that compared to EVs with a passive suspension system, the ones with AS system improve ride comfort, up to 31% reduction of the vehicle body acceleration RMS value, with an expense of higher energy consumption. This expense can be reduced to about 2.8% when using an energy harvesting AS system. Simulation results also demonstrate that the available energy for recuperation during the AS system operation is significant in relation to the regenerative braking energy of the propulsion system, up to approx. 70% on bumpy road surfaces.

Abstract Alternative vehicle technologies have a great potential to minimize the transportation-related environmental impacts, reduce the reliance of the U.S. on imported petroleum, and increase energy security. However, they introduce new uncertainties related to their environmental, economic, and social impacts and certain challenges for widespread adoption. In this study, a novel method, uncertainty-embedded dynamic life cycle sustainability assessment framework, is developed to address both methodological challenges and uncertainties in transportation sustainability research. The proposed approach provides a more comprehensive, system-based sustainability assessment framework by capturing the dynamic relations among the parameters within the U.S. transportation system as a whole with respect to its environmental, social, and economic impacts. Using multivariate uncertainty analysis, likelihood of the impact reduction potentials of different vehicle types, as well as the behavioral limits of the sustainability potentials of each vehicle type are analyzed. Seven sustainability impact categories are dynamically quantified for four different vehicle types (internal combustion, hybrid, plug-in hybrid, and battery electric vehicles) from 2015 to 2050. Although impacts of electric vehicles have the largest uncertainty, they are expected (90% confidence) to be the best alternative in long-term for reducing human health impacts and air pollution from transportation. While results based on deterministic (average) values indicate that electric vehicles have greater potential of reducing greenhouse gas emissions, plug-in hybrid vehicles have the largest potential according to the results with 90% confidence interval.

Air taxis are currently being demonstrated. Few studies have quantified their external effects in reducing on-road vehicle fuel consumption. The hypothesis of this paper is that air taxis may divert some drivers away from congested traffic corridors, improve traffic speed and fuel economy, and reduce congestion-induced energy consumption. A model is developed that links several key components: mode choice, the relationship between travel demand and traffic speeds, the relationship between traffic speeds and fuel economies, and the heterogenous value of travel time. It is applied to the route from downtown Los Angeles to Los Angeles International Airport, where at peak hours 38,200 vehicles attempt to use the route that has an hourly capacity of 17,200 vehicles. The model estimates that, with conservative assumptions and near-term technologies, diverting 3.2% of the traffic to air taxis could produce a 15% reduction in traffic vehicle fuel use. With optimistic assumptions and mature technologies, the study estimates that diverting 20% of traffic could reduce the traffic vehicle fuel use by about 74%. The key insight is that if a small share of congested travelers switched to air taxis, motivated by private benefits of time savings, significant external benefits for other road travelers (time savings and fuel savings) and to society (reduced energy use and emissions), would ensue creating a win-win-win outcome. These estimates (which are not intended as predictions because of the stated limitations) strongly suggest the need to consider the external energy effect in future cost-benefit analyses of air taxi technologies.

As part of continuous efforts to identify effective and durable anodes for use in cathodic protection (CP) of reinforced concrete bridge members, a water-based, electrically conductive paint was evaluated for use as the secondary anode in CP systems for inland concrete piers. The paint was used in two CP systems—one designed and built approximately 6 years ago and the other 8 years ago—to protect the concrete piers of two pairs of twin bridges in Virginia. When adjusted properly, the two systems provided more than sufficient protection to the reinforcing steel. Natural paint deterioration occurred in both systems. In the 8-year-old system, this deterioration ranged from 0 to 0.37 percent. In the 6-year-old system, it ranged from 0 to 0.14 percent. Most of the deterioration occurred at the ends of the pier caps, where the concrete is not sheltered from rain by a deck overhang. The overall performance of the conductive paint in these CP systems was better than expected. Its effectiveness could last for at least 15 years, even longer if minor paint deterioration is touched up as early as possible. This type of conductive paint should, therefore, be considered a suitable secondary anode for use in CP of inland concrete piers.

Current and forecasted use of air transportation by businesses in Minnesota using the Standard Industrial Classification is described. The research is based upon a study on air service and commercial and industrial activity in Minnesota required by the Minnesota legislature in 1996. Purchases from the air transportation sector that includes scheduled and nonscheduled passenger and freight services are based upon the 1993 IMPLAN input-output model for Minnesota and Bureau of Economic Analysis (BEA) and Bureau of Labor Statistics (BLS) forecasts for Minnesota. In addition to intraindustry transfers within the air transportation sector, purchases of air transportation are dominated by business associations, management and consulting services, and the U.S. Postal Service sectors. These four sectors also represent the sectors with the largest share of purchases of air transportation. BLS historical and forecast data suggest that the major group of industries that purchased air transportation in 1977 will remain intact through 2005. Under BEA forecasts for Minnesota, air transportation purchases by all industry sectors will increase more rapidly than other transportation modes. BEA also forecasts the air transportation component of gross state product growing faster than forecasted passenger originations at Minneapolis–St. Paul (MSP). The implications of the BEA forecasts will be considered in the next update of activity forecasts for MSP. This research is considered only the first step in understanding the role of air transportation to commerce and industry in Minnesota and other states.

In Bangladesh, prawn (Macrobrachium rosenbergii) farming remains dependent on the capture of wild postlarvae as hatchery production is still inadequate. However, prawn postlarvae fishing has been accompanied by concerns over recent climate change. Different climatic variables including cyclone, salinity, sea level rise, water temperature, flood, rainfall, and drought have had adverse effects on coastal ecosystem, thus determining a decline in the availability of prawn postlarvae and thereby catch. The households of postlarvae fishers also face a variety of socioeconomic constraints due to climate change. Considering extreme vulnerability to the effects of climate change, an integrated approach needs to be introduced to cope with the challenges.

Abstract Aluminum (Al)/air batteries have the potential to be used to produce power to operate cars and other vehicles. These batteries might be important on a long-term interim basis as the world passes through the transition from gasoline cars to hydrogen fuel cell cars. The Al/air battery system can generate enough energy and power for driving ranges and acceleration similar to gasoline powered cars. From our design analysis, it can be seen that the cost of aluminum as an anode can be as low as US$ 1.1/kg as long as the reaction product is recycled. The total fuel efficiency during the cycle process in Al/air electric vehicles (EVs) can be 15% (present stage) or 20% (projected) comparable to that of internal combustion engine vehicles (ICEs) (13%). The design battery energy density is 1300 Wh/kg (present) or 2000 Wh/kg (projected). The cost of battery system chosen to evaluate is US$ 30/kW (present) or US$ 29/kW (projected). Al/air EVs life-cycle analysis was conducted and compared to lead/acid and nickel metal hydride (NiMH) EVs. Only the Al/air EVs can be projected to have a travel range comparable to ICEs. From this analysis, Al/air EVs are the most promising candidates compared to ICEs in terms of travel range, purchase price, fuel cost, and life-cycle cost.

Bus services are a fundamental component of transportation networks in Latin America, but buses often account for a disproportionately large number of environmental externalities. Electric buses (e-buses) are emerging as an effective and pragmatic option for reducing greenhouse gas emissions and local pollutants. However, e-buses are difficult to procure in Latin America because of existing procurement challenges in the region, especially as those challenges relate to forming contracts to deal with high upfront costs and unknown risks. To overcome these procurement issues, this paper presents a new contractual model, based on literature and case study research. This new model suggests the separation of bus service responsibilities into three separate actors: multiple bus procurement companies, one or multiple bus depots and charging infrastructure companies, and multiple bus operating companies. By separating bus service responsibilities, the proposed model would bring about three concrete improvements: lower costs to the transit system, better quality of service, and lower-emission fleet deployment.

Transit bus passenger loading changes significantly over the course of a workday. Therefore, time-varying vehicle mass as a result of passenger load becomes an important factor in instantaneous energy consumption. Battery-powered electric transit buses have restricted range and longer “fueling” time compared with conventional diesel-powered buses; thus, it is critical to know how much energy they require. Our previous work has shown that instantaneous transit bus mass can be obtained by measuring the pressure in the vehicle’s airbag suspension system. This paper leverages this novel technique to determine the impact of time-varying mass on energy consumption. Sixty-five days of velocity and mass data were collected from in-use transit buses operating on routes in the Twin Cities, MN metropolitan area. The simulation tool Future Automotive Systems Technology Simulator was modified to allow both velocity and mass as time-dependent inputs. This tool was then used to model an electrified and conventional bus on the same routes and determine the energy use of each bus. Results showed that the kinetic intensity varied from 0.27 to 4.69 mi−1 and passenger loading ranged from 2 to 21 passengers. Simulation results showed that energy consumption for both buses increased with increasing vehicle mass. The simulation also indicated that passenger loading has a greater impact on energy consumption for conventional buses than for electric buses owing to the electric bus’s ability to recapture energy. This work shows that measuring and analyzing real-time passenger loading is advantageous for determining the energy used by electric and conventional diesel buses.