History and Outlook for Farm Bill Conservation Programs

Agricultural and Food Policy,

Potential Weight Benefits of IM7/8552 Hybrid Thin-Ply Composites for Aircraft Structures

Composite materials have increasingly been used for aerospace applications due to improved performance and reduced weight compared to their metallic counterparts. Inclusion of thin-ply material, plies with cured thickness half or less than standard-ply composites, have potential to improve performance and reduce structural weight further. The effect of thin-ply material on the weight of aircraft structure was investigated by examining wing cover weight reduction. To minimize the effects on manufacturing due to using thin plies, hybrid laminates were examined that used thin 45-degree plies to replace their standard-ply counterparts in laminates. Compression after impact (CAI) tests were conducted to examine the possible weight savings that could be gained by increasing the design allowables that were used to size the wing upper cover of a semi-span test article. A large increase in CAI strength was observed for quasi-isotropic hybrid laminates, whereas less improvement was seen for hard hybrid laminates such as found in the wing cover. For laminates design by CAI strength, weight savings of about 13% were found using the hybrid hard laminates compared to the standard-ply laminates. Whether similar weight savings could be expected for structure sized using tension after impact allowables will have to be investigated further. Notched specimens were tested to examine possible weight savings using hybrid laminates in regions that are sized using discrete source damage requirements. As expected, the hybrid laminate had marginal improvements over the standard-ply laminate for compression with a notch present. The hybrid laminate, however, exhibited about 20% lower strength than the standard-ply laminate counterpart for tension with a notch. The failure mode of the hybrid specimens was a brittle, self-similar crack, which differs from the standard-ply specimens that failed by significant amounts of delamination and fiber splitting. In light of the apparent reduction in notched tensile strength, additional investigation is required to assess the use of hybrid laminates for areas containing discrete source damage, and their effect on weight of such regions

INTEGRATED ASSESSMENT OF ENVIRONMENTAL EFFECTS FROM AGRICULTURAL PRODUCTION

Agriculture's impact on the environment is a complex research problem. A challenge to future economic research is to account for the interrelationship between agricultural production activities, soil productivity, erosion, and water quality. It will become increasingly important to determine not only the economic consequences, but also the environmental effectiveness of alternative policies aimed at improving resource use and quality. The application of biophysical simulation models to environmental quality problems provides a means to better understand the complex interaction between agricultural production and environmental quality.Environmental Economics and Policy,

Intensity Weighted Ranking: A Methodology for Understanding What Clients Tell Us

Although rank ordering of issues for needs assessment provides some information, this method does not capture the intensity of respondents concerns. This article presents a method of going beyond rank ordering to study both the intensity of response and uncover priorities for more than a few aggregated issues. Results from a survey of attendees of the Indiana State fair are utilized to illustrate the methodology

Using Technology to Survey New Audiences

A touch screen computer was set up at a state fair to assess citizen water quality concerns. Over 500 people took the survey. The researchers were able to reach citizens from both urban and rural areas. Respondents were aged from 18 to over 75. Most respondents (41%) felt that clean drinking water the most important water quality issue

Bargaining in Supply Chains (Long Version)

We study experimentally bargaining in a multiple-tier supply chain with horizontal competition and sequential bargaining between tiers. Our treatments vary the cost differences between firms in tiers 1 and 2. We measure how these underlying costs influence the efficiency, negotiated prices and profit distribution across the supply chain, and the consistency of these outcomes with existing theory. We find that the structural issue of cost differentials dominates personal characteristics in explaining outcomes, with profits in a tier generally increasing with decreased competition in the tier and increasing with decreased competition in alternate tiers. The Balanced Principal model of supply chain bargaining does a good job explaining our data, and outperforms the common assumption of leader-follower negotiations. We find a significant anchoring effect from a firm's first bid but no effect of the sequence of those bids, no evidence of failure to close via escalation of commitment, and mixed results for a deadline effect. We also find an interesting asymmetry between the buy and sells sides in employed bidding strategy. The buy side makes predominantly concessionary offers after the initial anchor, but a significant number of sell side firms engage in aggressive anti-concessionary bidding, a strategy that is effective in that it increases prices while not compromising closure rates.http://deepblue.lib.umich.edu/bitstream/2027.42/109717/1/1259_Lovejoy.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/109717/4/1259_Lovejoy_Mar2015.pdfDescription of 1259_Lovejoy_Mar2015.pdf : Long Version March 201

"GREEN TAXES": IMPACTS ON NATIONAL INCOME, SOCIAL WELFARE, AND ENVIRONMENTAL QUALITY

Two taxation schemes were designed to be included in a multi-regional multi-sectoral General Equilibrium model for reducing the use of commercial fertilizers, with the goal of alleviating surface water pollution. Under the 500% tax rate, results showed that 0.1% of the national income was given up in order to exchange for a 3% reduction in the fertilizer application used as an intermediate input. Furthermore environmental quality would be improved by 3%, if a linear relationship existed between the changes in intermediate fertilizer use and the improvement in environmental quality.Environmental Economics and Policy,

Communication Strategy: Does the Two-Step Still Work?

Much of our work in cooperative extension deals with the transfer of information or technology to clientele. Therefore, it is extremely important that we use the most effective and efficient means possible in carrying out this task

Designing Incentives in Startup Teams: Form and Timing of Equity Contracting

Entrepreneurial teams assign equity positions in their startups using a term sheet that details equity splits and conditions for being granted those splits. It is conventional wisdom in the entrepreneurial press that equal splits are poor choices. The conventional logic is that by not connecting rewards to contribution level equal split contracts can encourage free-riding behaviors. We experimentally test this conventional wisdom, among other entrepreneurial contracting hypotheses. Our results confirm the relationship between equal splits and depressed effort and contribution, but suggest a different causal sequence relative to conventional wisdom. Rather than the contract form being the primitive and the behavior the derived consequence, our results suggest the reverse. The differences in contract performance are driven primarily by the sorting of high contributors into non-equal contracts and of low contributors into equal contracts. However, delaying the contracting mitigates these sorting effects, reducing the effort gap between contracts. Taken together, our results suggest that both investors and founders should pay as much (or more) attention to personality type as they do to contract form, but if one is stuck with a given set of personalities delayed contracting (more so than contract form) can improve performance.https://deepblue.lib.umich.edu/bitstream/2027.42/138118/1/1372_Kagan.pd

Characterization of IM7/8552 Thin-Ply and Hybrid Thin-Ply Composites

Composite materials have increasingly been used for aerospace applications due to improved performance and reduced weight compared to their metallic counterparts. Inclusion of thin-ply material, plies with cured thickness half or less than standard composites, have potential to improve performance and reduce structural weight. Limited characterization of thin-ply IM7/8552 material in 30 and 70 grams per square meter fiber areal weights has been carried out using a series of selected American Society for Testing and Materials (ASTM) tests. Tests included unnotched tension, unnotched compression, v-notched rail shear, open-hole tension, and open-hole compression. Unidirectional, cross-ply, quasiisotropic and hybrid hard laminates were included in the study, and were compared to standard-ply laminates. Properties compared include fiber volume, laminate moduli, and failure strength, with failure modes also being examined. The thin-ply specimens exhibited similar or superior performance to standard ply laminates in many of the cases compared. Improvements in strength for laminates containing thin-ply material were seen for unidirectional laminates under unnotched tension, quasi-isotropic laminates under unnotched tension and compression, and hard laminates under open hole tension. Additional investigation is required to determine appropriate ply stacking rules for hybrids of thin and standard plies to avoid undesirable failure modes such as axial splitting. However, the observed performance improvements demonstrated by the conducted ASTM tests of hybrid thin-ply hard laminates could have benefits for improved structural weight in aircraft