Physical Sciences and Mathematics Commons^™

Dynamical Climatic Model For Time To Flowering In Vigna Radiata, Konstantin Kozlov, Alena Sokolkova, Cheng Ruei Lee, Chau Ti Ting, Roland Schafleitner, Eric Bishop-Von Wettberg, Sergey Nuzhdin, Maria Samsonova

College of Agriculture and Life Sciences Faculty Publications

Background: Phenology data collected recently for about 300 accessions of Vigna radiata (mungbean) is an invaluable resource for investigation of impacts of climatic factors on plant development. Results: We developed a new mathematical model that describes the dynamic control of time to flowering by daily values of maximal and minimal temperature, precipitation, day length and solar radiation. We obtained model parameters by adaptation to the available experimental data. The models were validated by cross-validation and used to demonstrate that the phenology of adaptive traits, like flowering time, is strongly predicted not only by local environmental factors but also by plant …

Non-Linear Regression Models For Time To Flowering In Wild Chickpea Combine Genetic And Climatic Factors, Konstantin Kozlov, Anupam Singh, Jens Berger, Eric Bishop-Von Wettberg, Abdullah Kahraman, Abdulkadir Aydogan, Douglas Cook, Sergey Nuzhdin, Maria Samsonova

College of Agriculture and Life Sciences Faculty Publications

Background: Accurate prediction of crop flowering time is required for reaching maximal farm efficiency. Several models developed to accomplish this goal are based on deep knowledge of plant phenology, requiring large investment for every individual crop or new variety. Mathematical modeling can be used to make better use of more shallow data and to extract information from it with higher efficiency. Cultivars of chickpea, Cicer arietanum, are currently being improved by introgressing wild C. reticulatum biodiversity with very different flowering time requirements. More understanding is required for how flowering time will depend on environmental conditions in these cultivars developed by …

Optimal Design Of Green Roofs: Mathematical Model And Experimental Evidence, Jing Hong

Theses and Dissertations

Green roofs ease the heat island effect and decrease stormwater runoff. Optimizing green roof design helps achieve these goals more efficiently. This dissertation proposes energy and mass models of green roofs and validates them through experimental evidence.

The energy and mass transfer models proposed in this dissertation can be programmed in any simulation tools, and benefits architects and engineers optimizing their green roof design. The mathematical models of green roofs were validated by the measured soil temperature and water content of the Golda Meir Library green roof.

Using energy and mass balance models, this research found the effects of the …

Characterizing Landscape-Scale Erosion Using 10be In Detrital Fluvial Sediment: Slope-Based Sampling Strategy Detects The Effect Of Widespread Dams, Lucas J. Reusser, Paul R. Bierman, Donna M. Rizzo, Eric W. Portenga, Dylan H. Rood

College of Engineering and Mathematical Sciences Faculty Publications

Concentrations of in situ 10Be measured in detrital fluvial sediment are frequently used to estimate long-term erosion rates of drainage basins. In many regions, basin-averaged erosion rates are positively correlated with basin average slope. The slope dependence of erosion allows model-based erosion rate estimation for unsampled basins and basins where human disturbance may have biased cosmogenic nuclide concentrations in sediment. Using samples collected from southeastern North America, we demonstrate an approach that explicitly considers the relationship between average basin slope and erosion rate. Because dams and reservoirs are ubiquitous on larger channels in the field area, we selected 36 undammed …

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …

A Financial Impact Assessment Of Ld 1725: Stream Crossings, New England Environmental Finance Center, Muskie School Of Public Service

Water

This report looks at the potential financial impact of LD 1725 on the estimated 30,000 stream crossings in the State of Maine that would be affected by the law. Our research for this report included the analysis of nearly 2000 stream crossings and the data collection necessary for the development of extensive stream crossing replacement cost models. We found that the 1.2 bankfull requirements in LD 1725 would result in a 75% ‐ 250% increase in structure widths for stream crossing projects across the state. An upsize of this magnitude would increase the cost of replacing stream crossings statewide by …

A Financial Impact Assessment Of Ld 1725: Stream Crossings (Presentation), New England Environmental Finance Center, Muskie School Of Public Service

Water

This report looks at the potential financial impact of LD 1725 on the estimated 30,000 stream crossings in the State of Maine that would be affected by the law. Our research for this report included the analysis of nearly 2000 stream crossings and the data collection necessary for the development of extensive stream crossing replacement cost models. We found that the 1.2 bankfull requirements in LD 1725 would result in a 75% ‐ 250% increase in structure widths for stream crossing projects across the state. An upsize of this magnitude would increase the cost of replacing stream crossings statewide by …

Culvert Material Cost Comparison, New England Environmental Finance Center

Water

The following tables provide a detailed look at the role that culvert material and culvert diameter play in the overall cost of a culvert replacement project.

Construction Cost Models, Barry Dikeman

Economics and Finance

The following are a series of cost estimate models similar in format to a typical engineer’s estimate that were developed in support of our financial impact assessment report for LD 1725. The models us current material costs, labor costs, and equipment costs for the region to provide a comparative cost analysis of seven culvert replacement scenarios. The models provide information about what the cost impact of LD 1725 would be for typical culvert replacements in Maine. However, due to the inherent restrictions of the cost modeling framework we were not able to include the abundance of variables that would be …

The Future Of Mineral Development On Federal Lands In The United States, John D. Leshy

The Future of Natural Resources Law and Policy (Summer Conference, June 6-8)

11 pages.

Includes bibliographical references

"Outline of presentation of John D. Leshy, Harry D. Sunderland Distinguished Professor, U.C. Hastings College of the Law, Natural Resources Law center, June 7, 2007" (pp. 3-5)

"Leshy draft 4.27.07 For Natural Resources Law Center" (pp. 6-13)

Model State Land Use Legislation For New England, New England Environmental Finance Center, Muskie School Of Public Service

Legislation

Sprawl is neither the ordained nor the inevitable outcome upon the New England landscape. A coordinated response to sprawl by the public and private sectors is possible, and could dramatically improve land use patterns and reduce the cost of local government. For the New England states, such a response would include, among other elements, legislation to eliminate existing gaps in the land use laws of each state – gaps that presently encourage or sanction sprawling development. It would also include incentives for municipalities to think beyond their borders and to act with greater efficiency and effect. It is the purpose …

Creep And Creep-Recovery Models For Wood Under High Stress Levels, Zhiyong Cai, Kenneth J. Fridley, Michael O. Hunt, David V. Rosowsky

Civil and Environmental Engineering and Construction Faculty Research

Forty small clear southern pine specimens were loaded under third-point bending to examine creep and creep-recovery behavior for wood under high stress levels. Stress levels of between 69% and 91% of the predicted static strength were applied for 23 h with 1 h allowed for recovery, and the resulting deflection vs. time behavior was studied. The experimental creep and creep-recovery behavior was modeled using modified power law functions. The results indicate that these functions provide the best fit to both primary and secondary experimental data. The empirical models can be used to simulate the viscoelastic behavior of wood under high …