6,929 research outputs found
On ordinal utility, cardinal utility, and random utility Â
Though the Random Utility Model (RUM) was conceivedÂ
entirely in terms of ordinal utility, the apparatus throughwhich it is widely practised exhibits properties ofÂ
cardinal utility.  The adoption of cardinal utility as aÂ
working operation of ordinal is perfectly valid, providedÂ
interpretations drawn from that operation remain faithfulÂ
to ordinal utility.  The paper considers whether the latterrequirement holds true for several measurements commonlyÂ
derived from RUM.  In particular it is found thatÂ
measurements of consumer surplus change may depart fromÂ
ordinal utility, and exploit the cardinality inherent inÂ
the practical apparatus.
Characterization of a high-pressure diesel fuel injection system as a control technology option to improve engine performance and reduce exhaust emissions
Test results from a high pressure electronically controlled fuel injection system are compared with a commercial mechanical injection system on a single cylinder, diesel test engine using an inlet boost pressure of 2.6:1. The electronic fuel injection system achieved high pressure by means of a fluid intensifier with peak injection pressures of 47 to 69 MPa. Reduced exhaust emissions were demonstrated with an increasing rate of injection followed by a fast cutoff of injection. The reduction in emissions is more responsive to the rate of injection and injection timing than to high peak injection pressure
Solution of a Braneworld Big Crunch/Big Bang Cosmology
We solve for the cosmological perturbations in a five-dimensional background
consisting of two separating or colliding boundary branes, as an expansion in
the collision speed V divided by the speed of light c. Our solution permits a
detailed check of the validity of four-dimensional effective theory in the
vicinity of the event corresponding to the big crunch/big bang singularity. We
show that the four-dimensional description fails at the first nontrivial order
in (V/c)^2. At this order, there is nontrivial mixing of the two relevant
four-dimensional perturbation modes (the growing and decaying modes) as the
boundary branes move from the narrowly-separated limit described by
Kaluza-Klein theory to the well-separated limit where gravity is confined to
the positive-tension brane. We comment on the cosmological significance of the
result and compute other quantities of interest in five-dimensional
cosmological scenarios.Comment: 54 pages, 12 figures, URL updated & 3 references adde
Essays on climate change adaptation and biotechnologies in U.S. agriculture
This dissertation examines climate change adaptation and biotechnologies in United States (US) agriculture. The first essay seeks a better understanding of the long-term and short-term implications of climate change for corn yields. Bayesian dynamic regressions are estimated for non-irrigated counties during 1960-2011 and used to forecast over 2012-2031. Yields are forecasted to generally increase 10-40\% over current averages by 2031, with the Corn Belt and Great Lakes experiencing the greatest growth. The long-run relationship between climate damages and Hicks-neutral technical change is then estimated. Standard damage functions are generalized to include extreme temperatures and precipitation, while controlling for soil productivity. Results indicate significant connections between climate damages and technical change and suggest adaptation possibilities beyond 2031.
The second essay examines consumer demand for genetically modified potatoes. The US potato industry is working to lower acrylamide content, a probable human carcinogen forming naturally in potatoes and processed potato products cooked at high temperatures. Using random nth price auctions, we test combined effects of food labels and information on willingness-to-pay (WTP) for conventional potatoes and potato products using biotechnology to reduce acrylamide levels. Each subject receives a randomly-assigned information treatment that consists of one or two perspectives, e.g., an industry, scientific, and/or “environmental group” perspective. Results show for the first time that US consumers are willing to pay a premium for food safety obtained using biotechnology for two popular foods in the American diet.
The third essay expands on previous agriculture-climate links by investigating the role of environmental inputs and climate on cropland use and allocation. A discrete-continuous model of crop-tillage combinations and acreage allocation is estimated using field-level data. In the first step, a multinomial logit model is used to estimate farmers’ choices of crops and tillage. In the second step, linear regressions quantify the impacts of climate, economic factors, management, and soil characteristics on crop acreage. There are significant climate impacts on optimal input use. No-till practices may be an effective adaptation strategy to intense heat and precipitation in the short run. In the long run, farmers may adjust crops and acreage, depending on relative output prices and soil characteristics
Baseline performance and emissions data for a single-cylinder, direct-injected diesel engine
Comprehensive fuel consumption, mean effective cylinder pressure, and emission test results for a supercharged, single-cylinder, direct-injected, four-stroke-cycle, diesel test engine are documented. Inlet air-to-exhaust pressure ratios were varied from 1.25 to 3.35 in order to establish the potential effects of turbocharging techniques on engine performance. Inlet air temperatures and pressures were adjusted from 34 to 107 C and from 193 to 414 kPa to determine the effects on engine performance and emissions. Engine output ranged from 300 to 2100 kPa (brake mean effective pressure) in the speed range of 1000 to 3000 rpm. Gaseous and particulate emission rates were measured. Real-time values of engine friction and pumping loop losses were measured independently and compared with motored engine values
How a National Carbon Policy Could Affect Grain Variety Selection: The Case of Rice in Arkansas
This study conducts a life cycle assessment (LCA) of carbon emissions and estimates the carbon sequestered in 14 commonly sown rice varieties across the Arkansas Delta. Given the uncertainty regarding future carbon legislation, and increased consumer and industry demand for “greener” products, this study estimates how potential carbon policies would affect rice cultivar selection Hybrid rice varieties, given their higher yield and higher yield per unit of green house gas (GHG) emission, are better positioned to take advantage of any increase in consumer demand for “greener” products and/or absorb any government policy better than conventional rice cultivars.Rice, Carbon Policy, Cap and Trade, Carbon Offset, Agricultural and Food Policy, Crop Production/Industries, Environmental Economics and Policy, Q52, Q54, Q58,
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