An Analysis of Regional Economic Growth in the U.S. Midwest, April 2005

In this paper we examine some of the economic forces that underlie economic growth at the county level. In an effort to describe a much more comprehensive regional economic growth model, we address a variety of different growth hypotheses by introducing a large number of growth related variables. When formulating our hypotheses and specifying our growth model we make liberal use of GIS (geographical information systems) mapping software to “paint” a picture of where growth spots exist. Our empirical estimation indicates that amenities, state and local tax burdens, population, amount of primary agriculture activity, and demographics have important impacts on economic growth.

What can the United States learn from Spain's Pork Sector? Implications from a Comparative Economic Analysis, September 2005

This study provides a comparative economic analysis of the primary production of pork and its marketing channel in Spain and the United States. The focus on Spain is due to the profound growth and transformation of its pork sector over the last 20 years, compared with other major players in the world market for pig meat. The analysis reveals a number of similar characteristics but also important differences between the two countries. The significant expansion of Spain’s pork production sector stemmed from a number of factors that apply, to a relatively large extent, to some U.S. states (in particular, North Carolina) but do not apply to the U.S. pork production sector as a whole. This implies that it is unlikely that the U.S. pork production sector as a whole will mimic an expansion driven by the same type of factors in the future. Likewise, it seems highly unlikely that the U.S. consumption of pig meat will expand in the future based on the same driving forces behind the sharp increase in Spain’s domestic demand for pig meat over the last 20 years. The analysis also indicates that Spanish pig producers are currently being subjected to more stringent environmental and animal welfare regulations than their U.S. counterparts and that these regulations are becoming increasingly more restrictive. It would not be surprising to see similar trends emerging in the United States, leading to a substantially more restrictive regulatory environment for U.S. hog producers.

The Growth and Direction of the Biodiesel Industry in the United States, 2007

The biodiesel industry in the United States has realized significant growth over the past decade through large increases in annual production and production capacity and a transition from smaller batch plants to larger-scale continuous producers. The larger, continuous-flow plants provide operating cost advantages over the smaller batch plants through their ability to capture co-products and reuse certain components in the production process. This paper uses a simple capital budgeting model developed by the authors along with production data supplied by industry sources to estimate production costs, return-on-investment levels, and break-even conditions for two common plant sizes (30 and 60 million gallon annual capacities) over a range of biodiesel and feedstock price levels. The analysis shows that the larger plant realizes returns to scale in both labor and capital costs, enabling the larger plant to pay up to $0.015 more per pound for the feedstock to achieve equivalent return levels as the smaller plant under the same conditions. The paper contributes to the growing literature on the biodiesel industry by using the most current conversion rates for the production technology and current price levels to estimate biodiesel production costs and potential plant performance, providing a useful follow-up to previous studies.

An illustration of the ALLOC 6B location-allocation analysis system, 1984

The programs included in this Discussion Paper no. 17 are Distance, Unravel, Retrench and Alloc 6B that deal with location-allocation analyses first published in 1973 by the Department of Geography, The University of Iowa.

Expansive Mineral Growth and Concrete Deterioration, HR-384, 1997

A significant question is: What role does newly-formed expansive mineral growth play in the premature deterioration of concrete? These minerals (ettringite and brucite) are formed in cement paste as a result of chemical reactions involving cement and coarse/fine aggregate. Petrographic observations and SEM/EDAX analysis were conducted in order to determine chemical and mineralogical changes in the aggregate and cement paste of samples taken from Iowa concrete highways that showed premature deterioration. Mechanisms involved in deterioration were investigated. A second objective was to investigate whether deicer solutions exacerbate the formation of expansive minerals and concrete deterioration. Magnesium in deicer solutions causes the most severe paste deterioration by forming non-cementitious magnesium silicate hydrate and brucite. Chloride in deicer solutions promotes decalcification of paste and alters ettringite to chloroaluminate. Calcium magnesium acetate (CMA) and magnesium acetate (Mg-acetate) produce the most deleterious effects on concrete, with calcium acetate (Ca-acetate) being much less severe.

Analysis and Forecast of Housing Needs in Iowa Technical Report, January 22, 2013

The research and analysis summarized in this report prepared by Gruen Gruen + Associates (“GG+A”) provides an information base about population, household, housing, and employment conditions and trends affecting the current and future housing needs of Iowans. It also provides a synthesis of how the housing needs of Iowans have changed over the past decade and how needs are likely to continue to change over the present decade (2010-2020), given forecast employment and population growth in Iowa.