The detailed characterization of Martian impact craters from the 1/16 degree MOLA global topography grid

We describe a new project to obtain a global characterisation of Martian impact crater morphology from the 1/16 degree MOLA topography dataset. A new mathematical method applicable to both symmetric and asymmetric craters is used

Evaluation of the volumetric erosion of spherical electrical contacts using the defect removal method

Volumetric erosion is regarded as a significant index for studying the erosion process of electrical switching contacts. Three-dimensional (3-D) surface measurement techniques provide an approach to investigate the geometric characteristics and volumetric erosion of electrical contacts. This paper presents a concrete data-processing procedure for evaluating volumetric erosion of spherical electrical contacts from 3-D surface measurement data using the defect removal method (DRM). The DRM outlined by McBride is an algorithm for evaluating the underlying form (prior to erosion) parameters of the surfaces with localized erosion and allowing the erosion characteristics themselves to be isolated. In this paper, a number of spherical electrical contacts that had undergone various electrical operations were measured using a 3-D surface profiler, the underlying form parameters of the eroded contacts were evaluated using the DRM, and then the volumetric erosions were isolated and calculated. The analysis of the correlations between the volumetric erosion and the number of switching cycles of electrical operation that the contacts had undergone showed a more accurate and reliable volumetric erosion evaluation using the DRM than that without using the DRM

DOES CONTRACTING RAISE FARM PRODUCTIVITY? THE IMPACT OF PRODUCTION CONTRACTS ON HOG FARM PERFORMANCE

The costs and benefits of policies designed to regulate the use of production contracts will depend in part on the impact of these contracts on farm productivity. In this paper we measure the impact of contracting on 1) partial and total factor productivity and 2) the production technology for 479 US hog operations. A sample selection model accounts for the fact that unobservable variables may be correlated with both the decision to contract and farm productivity. Results also identify determinants of farmers' decisions to contract and factors influencing farm productivity.Livestock Production/Industries, Productivity Analysis,

FACTORS AFFECTING CONTRACTOR AND GROWER SUCCESS IN HOG CONTRACTING

This study analyzes a national survey of U.S. hog producers within a principal-agent framework in order to examine factors affecting contractor and grower success in hog contracting. Several factors had differential impacts on contractor and grower returns. Results suggest that there may be a role for public policy in ensuring that contract arrangements are conducted fairly.Livestock Production/Industries,

Impact of the Patient Protection and Affordable Care Act on Covered Persons

Estimates how proposed reforms would affect health insurance coverage rates in each state and what percentage of the newly covered would benefit from provisions for Medicaid, subsidies, mandates, and children. Compares rural and urban areas

The Transformation of U.S. Livestock Agriculture: Scale, Efficiency, and Risks

U.S. livestock production has shifted to much larger and more specialized farms, and the various stages of input provision, farm production, and processing are now much more tightly coordinated through formal contracts and shared ownership of assets. Important financial advantages have driven these structural changes, which in turn have boosted productivity growth in the livestock sector. But structural changes can also generate environmental and health risks for society, as industrialization concentrates animals and animal wastes in localized areas. This report relies on farm-level data to detail the nature, causes, and effects of structural changes in livestock production.Livestock, dairy, broilers, hogs, fed cattle, farm structure, scale economies, contract agriculture, CAFOs, growth-promoting antibiotics, Farm Management, Livestock Production/Industries,

ADOPTION OF BIOENGINEERED CROPS

Use of crop biotechnology products, such as genetically engineered (GE) crops with input traits for pest management, has risen dramatically since commercial approval in the mid-1990s. This report addresses several of the economic dimensions regarding farmer adoption of bioengineered crops, including herbicidetolerant and insect-resistant varieties. In particular, the report examines: (1) the extent of adoption of bioengineered crops, their diffusion path, and expected adoption rates over the next few years; (2) factors affecting the adoption of bioengineered crops; and (3) farm-level impacts of the adoption of bioengineered crops. Data used in the analysis are mostly from USDA surveys.Biotechnology, technology adoption, genetic engineering, pest management, financial effects, tillage, herbicide-tolerant crops, Bt crops, corn, soybeans, cotton, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Critical soft landing technology issues for future US space missions

A programmatic need for research and development to support parachute-based landing systems has not existed since the end of the Apollo missions in the mid-1970s. Now, a number of planned space programs require advanced landing capabilities for which the experience and technology base does not currently exist. New requirements for landing on land with controllable, gliding decelerators and for more effective impact attenuation devices justify a renewal of the landing technology development effort that existed during the Mercury, Gemini, and Apollo programs. A study was performed to evaluate the current and projected national capability in landing systems and to identify critical deficiencies in the technology base required to support the Assured Crew Return Vehicle and the Two-Way Manned Transportation System. A technology development program covering eight landing system performance issues is recommended

Policy Reform in the Tobacco Industry: Producers Adapt to a Changing Market

The Fair and Equitable Tobacco Reform Act of 2004 eliminated tobacco quotas and tobacco price supports and allowed producers to plant any amount or type of tobacco regardless of geographic location. The authors found that flue-cured tobacco producers made greater adjustments to their operations after the buyout than did burley tobacco producers. Flue-cured tobacco producers were more likely to increase tobacco acres per farm, pushing up the tobacco acreage per farm at a faster rate compared with burley tobacco producers. Flue-cured producers also were more likely to invest in their tobacco enterprises and invested more per farm after 2004. As a result of increased acreage, tobacco operations became more sensitive to changes in labor costs. With over 75 percent of tobacco farms using hired or contract labor in 2008, the availability and cost of workers have become increasingly important to tobacco producers. This report is based on data collected from the tobacco version of the 2008 Agricultural Resource Management Survey (ARMS), which focused on U.S. producers of burley and flue-cure tobacco in 2008 and how their tobacco operations have changed since 2000 and 2004.Tobacco, structural change, farm adjustments, adaptations, Agricultural Resources Management Survey (ARMS) Acknowledgments, Agricultural and Food Policy, Crop Production/Industries, Farm Management,