New vehicle characteristics and the cost of the corporate average fuel economy standard

Recent legislation has increased the Corporate Average Fuel Economy (CAFÉ) standard by 40 percent, which represents the first major increase in the standard since its creation in 1975. Previous analysis of the CAFÉ standard has focused on the short run effects, in which vehicle characteristics are held fixed, or the long run, when firms can adopt new powertrain technology. This paper focuses on the medium run, when firms can choose characteristics such as weight and power, and have a limited ability to adopt engine technology. We first document the historical importance of the medium run and then estimate consumers’ willingness-to-pay for fuel efficiency, power and weight. We employ a unique empirical strategy that accounts for the characteristics’ endogeneity, which has not been addressed in the literature, by using variation in the set of engine models used in vehicle models. The results imply that an increase in power has an equal effect on vehicle sales as a proportional increase in fuel efficiency. We then simulate the medium run effects of an increase in the CAFÉ standard. The policy reduces producer and consumer welfare and causes substantial transfers across firms, but the effects are significantly smaller than in previous studies.Fuel

The price of gasoline and the demand for fuel economy: evidence from monthly new vehicles sales data

This paper uses a unique data set of monthly new vehicle sales by detailed model from 1978- 2007, and implements a new identification strategy to estimate the effect of the price of gasoline on consumer demand for fuel economy. We control for unobserved vehicle and consumer characteristics by using within model-year changes in the price of gasoline and vehicle sales. We find a significant demand response, as nearly half of the decline in market share of U.S. manufacturers from 2002-2007 was due to the increase in the price of gasoline. On the other hand, an increase in the gasoline tax would only modestly affect average fuel economy.Gasoline ; Automobiles - Prices

Geometrically exact Cosserat rods with Kelvin–Voigt type viscous damping

We present the derivation of a simple viscous damping model of Kelvin–Voigt type for geometrically exact Cosserat rods from three-dimensional continuum theory. Assuming moderate curvature of the rod in its reference configuration, strains remaining small in its deformed configurations, strain rates that vary slowly compared to internal relaxation processes, and a homogeneous and isotropic material, we obtain explicit formulas for the damping parameters of the model in terms of the well known stiffness parameters of the rod and the retardation time constants defined as the ratios of bulk and shear viscosities to the respective elastic moduli. We briefly discuss the range of validity of the Kelvin–Voigt model and illustrate its behaviour for large bending deformations with a numerical example

Temperature-dependent regulation of d-cis-[3H]diltiazem binding to Ca2+ channels by 1,4-dihydropyridine channel agonists and antagonists

AbstractThe binding of the Ca2+-channel blocker d-cis-[3H]diltiazem to guinea pig skeletal muscle microsomes is temperature-dependent. At 2°C the KD is 39 nM and Bmax is 11 pmol/mg protein. The binding is fully reversible (K−1 = 0.02 min−1). The binding sites discriminate between the diastereoisomers 1- and d-cis-diltiazem, recognize verapamil, gallopamil and tiapamil, and are sensitive to La3+-inhibition. At 30°C the KD is 37 nM and the Bmax is 2.9 pmol/mg protein. D-cis-diltiazem-labelling is regulated by the 1,4-dihydropyridine Ca2+-channel blockers and a novel Ca2+-channel activator in a temperature-dependent manner. At 30°C an enhancement of d-cis-diltiazem binding by the channel blockers is observed. This is attributed to a Bmax increase. EC50-values for enhancement and the maximal enhancement differ for the individual 1,4-dihydropyridines. At 2°C 1,4-dihydropyridines inhibit d-cis-[3H]diltiazem binding. This is attributed to a Bmax decrease. We have directly labelled one of the drug receptor sites within the Ca2+-channel which can allosterically interact with the 1,4-dihydropyridine binding sites

Biology of Surgeonfish Acanthurus-nigrofuscus with emphasis on changeover in diet and annual gonadal cycles

A 3 yr study was conducted on the feeding biology and reproductive strategies of Acanthurus nigrofuscus (Acanthuridae, Teleostei) found along the coral reefs of the Gulf of Aqaba and forming there the major biomass of algivorous fish. The diet of this surgeonfish is based on algae selected from turf communities growing on subtidal rocky surfaces. At some sites A. nigrofuscus form schools that migrate daily from nocturnal refuges in coral reefs to foraging sites on the intertidal, covering distances of 500 to 600 m. During summer the main food items are brown and red algae; in winter, lush green algae. This changeover appears to provide the food-base for accumulation of fat and recrudescence of gonadal activity initiating in March-Apnl. Reproduction occurs in large schools of 2000 to 2500 fish and on selected sites, continuing from May to September. Spawning occurs daily from 1800 to 1830 h, after which the fish depart for their night refuges. Peak of gonadal activity is in July-August, after whch an increase of pre- and postovulatory atretic bodes is prominent. In female post-spawned gonads, cysts of spermatogonia appear and remain until renewed normal activity in February-March. Histological evidence and possible explanation of this phenomenon are provided