Lithuania’s Food Demand During Economic Transition, January 2000

The linear approximate version of the AIDS model is estimated using data from the Lithuanian household budget survey covering the period from July 1992 to December 1994. Price and real expenditure elasticities for twelve food groups were estimated based on the estimated coefficients of the model. Very little or nothing is known about the demand parameters of Lithuania and other former socialist countries, so the results are of intrinsic interest. Estimated expenditure elasticities were positive and statistically significant for all food groups while all own-price elasticities were negative and statistically significant, except for that of eggs which was insignificant. Results suggest that Lithuanian household consumption did respond to price and real income changes during their transition to a market-oriented economy.

F-1 Food Assistance Program State Summary, September 2005

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, October 2005

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, November 2005

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, December 2005

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1, Food Assistance Program State Summary, January 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

Source wavelet estimation for waveform inversion of crosshole georadar data

AbstractFor a wide range of environmental, hydrological, and engineering applications there is a fast growing need for high-resolution imaging. In this context, waveform tomographic imaging of crosshole georadar data is a powerful method able to provide images of pertinent electrical properties in near-surface environments with unprecedented spatial resolution. In contrast, conventional ray-based tomographic methods, which consider only a very limited part of the recorded signal (first-arrival traveltimes and maximum first-cycle amplitudes), suffer from inherent limitations in resolution and may prove to be inadequate in complex environments. For a typical crosshole georadar survey the potential improvement in resolution when using waveform-based approaches instead of ray-based approaches is in the range of one order-of- magnitude. Moreover, the spatial resolution of waveform-based inversions is comparable to that of common logging methods. While in exploration seismology waveform tomographic imaging has become well established over the past two decades, it is comparably still underdeveloped in the georadar domain despite corresponding needs. Recently, different groups have presented finite-difference time-domain waveform inversion schemes for crosshole georadar data, which are adaptations and extensions of Tarantola's seminal nonlinear generalized least-squares approach developed for the seismic case. First applications of these new crosshole georadar waveform inversion schemes on synthetic and field data have shown promising results. However, there is little known about the limits and performance of such schemes in complex environments. To this end, the general motivation of my thesis is the evaluation of the robustness and limitations of waveform inversion algorithms for crosshole georadar data in order to apply such schemes to a wide range of real world problems.One crucial issue to making applicable and effective any waveform scheme to real-world crosshole georadar problems is the accurate estimation of the source wavelet, which is unknown in reality. Waveform inversion schemes for crosshole georadar data require forward simulations of the wavefield in order to iteratively solve the inverse problem. Therefore, accurate knowledge of the source wavelet is critically important for successful application of such schemes. Relatively small differences in the estimated source wavelet shape can lead to large differences in the resulting tomograms. In the first part of my thesis, I explore the viability and robustness of a relatively simple iterative deconvolution technique that incorporates the estimation of the source wavelet into the waveform inversion procedure rather than adding additional model parameters into the inversion problem. Extensive tests indicate that this source wavelet estimation technique is simple yet effective, and is able to provide remarkably accurate and robust estimates of the source wavelet in the presence of strong heterogeneity in both the dielectric permittivity and electrical conductivity as well as significant ambient noise in the recorded data. Furthermore, our tests also indicate that the approach is insensitive to the phase characteristics of the starting wavelet, which is not the case when directly incorporating the wavelet estimation into the inverse problem.Another critical issue with crosshole georadar waveform inversion schemes which clearly needs to be investigated is the consequence of the common assumption of frequency- independent electromagnetic constitutive parameters. This is crucial since in reality, these parameters are known to be frequency-dependent and complex and thus recorded georadar data may show significant dispersive behaviour. In particular, in the presence of water, there is a wide body of evidence showing that the dielectric permittivity can be significantly frequency dependent over the GPR frequency range, due to a variety of relaxation processes. The second part of my thesis is therefore dedicated to the evaluation of the reconstruction limits of a non-dispersive crosshole georadar waveform inversion scheme in the presence of varying degrees of dielectric dispersion. I show that the inversion algorithm, combined with the iterative deconvolution-based source wavelet estimation procedure that is partially able to account for the frequency-dependent effects through an "effective" wavelet, performs remarkably well in weakly to moderately dispersive environments and has the ability to provide adequate tomographic reconstructions.

F-1, Food Assistance Program State Summary, February 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, March 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, April 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1, Food Assistance Program State Summary, May 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1 Food Assistance Program State Summary, June 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.

F-1, Food Assistance Program State Summary, July 2006

The Food Assistance Monthly Participation Report is a monthly summary of Food Assistance program participation, Statewide and for each Iowa county. Breakouts are reported for participants also in the FIP program, those only receiving Food Assistance, and those that are receiving economic assistance under other programs (primarily Medicaid). This report may also be known as the F-1 Report.