On the accuracy of nonsurvey regional input-output multipliers: An empirical study

Correct specification of the simple location quotients in regionalizing the national direct requirements table is essential to the accuracy of regional input-output multipliers. The purpose of this research is to examine the relative accuracy of these multipliers when earnings, employment, number of establishments, and payroll data specify the simple location quotients.^ For each specification type, I derive a column of total output multipliers and a column of total income multipliers. These multipliers are based on the 1987 benchmark input-output accounts of the U.S. economy and 1988-1992 state of Florida data.^ Error sign tests, and Standardized Mean Absolute Deviation (SMAD) statistics indicate that the output multiplier estimates overestimate the output multipliers published by the Department of Commerce-Bureau of Economic Analysis (BEA) for the state of Florida. In contrast, the income multiplier estimates underestimate the BEA's income multipliers. For a given multiplier type, the Spearman-rank correlation analysis shows that the multiplier estimates and the BEA multipliers have statistically different rank ordering of row elements. The above tests also find no significant different differences, both in size and ranking distributions, among the vectors of multiplier estimates. ^

Assessing the effectiveness of two-year banking and insurance technology programs of junior colleges in Taiwan, R.O.C.: An application of the Context Input Process Product (CIPP) evaluation model

The purpose of this descriptive study was to evaluate the banking and insurance technology curriculum at ten junior colleges in Taiwan. The study focused on curriculum, curriculum materials, instruction, support services, student achievement and job performance. Data was collected from a diverse sample of faculty, students, alumni, and employers. ^ Questionnaires on the evaluation of curriculum at technical junior colleges were developed for use in this specific case. Data were collected from the sample described above and analyzed utilizing ANOVA, T-Tests and crosstabulations. Findings are presented which indicate that there is room for improvement in terms of meeting individual students' needs. ^ Using Stufflebeam's CIPP model for curriculum evaluation it was determined that the curriculum was adequate in terms of the knowledge and skills imparted to students. However, students were dissatisfied with the rigidity of the curriculum and the lack of opportunity to satisfy the individual needs of students. Employers were satisfied with both the academic preparation of students and their on the job performance. ^ In sum, the curriculum of the two-year banking and insurance technology programs of junior college in Taiwan was shown to have served adequately preparing a work force to enter businesses. It is now time to look toward the future and adapt the curriculum and instruction for the future needs of the ever evolving high-tech society. ^

Relative significance of pelagic, benthic and allochthonous organic matter to microbial carbon cycling in a phosphorus-depleted subtropical estuary (Florida Bay)

Heterotrophic bacteria are important decomposers and transformers of primary production and provide an important link between detritus and the aquatic food web. In seagrass ecosystems, much of seagrass primary production is unavailable through direct grazing and must undergo microbial reworking before seagrass production can enter the aquatic food web. The goal of my dissertation research is to understand better the role heterotrophic bacteria play in carbon cycling in seagrass estuaries. My dissertation research focuses on Florida Bay, a seagrass estuary that has experienced recent changes in carbon source availability, which may have altered ecosystem function. My dissertation research investigates the importance of seagrass, algal and/or cyanobacterial, and allochthonous-derived organic matter to heterotrophic bacteria in Florida Bay and helps establish the carbon base of the estuarine food web. ^ A three tiered approach to the study of heterotrophic bacterial carbon cycling and trophic influences in Florida Bay was used: (1) Spatiotemporal observations of environmental parameters (hydrology, nutrients, extracellular enzymes, and microbial abundance, biomass, and production); (2) Microbial grazing experiments under different levels of top-down and bottom-up influence; and (3) Bulk and compound-specific (bacteria-biomarker fatty acid analysis) stable carbon isotope analysis. ^ In Florida Bay, spatiotemporal patterns in microbial extracellular enzyme (also called ectoenzyme) activities indicate that microorganisms hydrolyzed selectively fractions of the estuarine organic matter pool. The microbial community hydrolyzed organic acids, peptides, and phosphate esters and did not use storage and structural carbohydrates. Organic matter use by heterotrophic bacterioplankton in Florida Bay was co-regulated by bottom-up (resource availability) and top-down (grazer mediated) processes. A bacterial carbon budget based on bacterial, epiphytic, and seagrass production indicates that heterotrophic bacterial carbon cycles are supported primarily through epiphytic production with mixing from seagrass production. Stable carbon isotope analysis of bacteria biomarkers and carbon sources in Florida Bay corroborate the results of the bacterial carbon budget. These results support previous studies of aquatic consumers in Florida Bay, indicating that epiphytic/benthic algal and/or cyanobacterial production with mixing from seagrass-derived organic matter is the carbon base of the seagrass estuarine food web. ^

Orthogonal frequency division multiplexing based air interfaces and multiple input multiple output techniques in cooperative satellite communications for 4th generation mobile systems

Recently, wireless network technology has grown at such a pace that scientific research has become a practical reality in a very short time span. Mobile wireless communications have witnessed the adoption of several generations, each of them complementing and improving the former. One mobile system that features high data rates and open network architecture is 4G. Currently, the research community and industry, in the field of wireless networks, are working on possible choices for solutions in the 4G system. 4G is a collection of technologies and standards that will allow a range of ubiquitous computing and wireless communication architectures. The researcher considers one of the most important characteristics of future 4G mobile systems the ability to guarantee reliable communications from 100 Mbps, in high mobility links, to as high as 1 Gbps for low mobility users, in addition to high efficiency in the spectrum usage. On mobile wireless communications networks, one important factor is the coverage of large geographical areas. In 4G systems, a hybrid satellite/terrestrial network is crucial to providing users with coverage wherever needed. Subscribers thus require a reliable satellite link to access their services when they are in remote locations, where a terrestrial infrastructure is unavailable. Thus, they must rely upon satellite coverage. Good modulation and access technique are also required in order to transmit high data rates over satellite links to mobile users. This technique must adapt to the characteristics of the satellite channel and also be efficient in the use of allocated bandwidth. Satellite links are fading channels, when used by mobile users. Some measures designed to approach these fading environments make use of: (1) spatial diversity (two receive antenna configuration); (2) time diversity (channel interleaver/spreading techniques); and (3) upper layer FEC. The author proposes the use of OFDM (Orthogonal Frequency Multiple Access) for the satellite link by increasing the time diversity. This technique will allow for an increase of the data rate, as primarily required by multimedia applications, and will also optimally use the available bandwidth. In addition, this dissertation approaches the use of Cooperative Satellite Communications for hybrid satellite/terrestrial networks. By using this technique, the satellite coverage can be extended to areas where there is no direct link to the satellite. For this purpose, a good channel model is necessary.

Sediment and soil organic matter source assessment as revealed by the molecular distribution and carbon isotopic composition of n-alkanes

The assessment of organic matter (OM) sources in sediments and soils is a key to better understand the biogeochemical cycling of carbon in aquatic environments. While traditional molecular marker-based methods have provided such information for typical two end member (allochthonous/terrestrial vs. autochthonous/microbial)-dominated systems, more detailed, biomass-specific assessments are needed for ecosystems with complex OM inputs such as tropical and sub-tropical wetlands and estuaries where aquatic macrophytes and macroalgae may play an important role as OM sources. The aim of this study was to assess the utility of a combined approach using compound specific stable carbon isotope analysis and an n-alkane based proxy (Paq) to differentiate submerged and emergent/terrestrial vegetation OM inputs to soils/sediments from a sub-tropical wetland and estuarine system, the Florida Coastal Everglades. Results show that Paq values (0.13–0.51) for the emergent/terrestrial plants were generally lower than those for freshwater/marine submerged vegetation (0.45–1.00) and that compound specific δ13C values for the n-alkanes (C23 to C31) were distinctively different for terrestrial/emergent and freshwater/marine submerged plants. While crossplots of the Paq and n-alkane stable isotope values for the C23n-alkane suggest that OM inputs are controlled by vegetation changes along the freshwater to marine transect, further resolution regarding OM input changes along this landscape was obtained through principal component analysis (PCA), successfully grouping the study sites according to the OM source strengths. The data show the potential for this n-alkane based multi-proxy approach as a means of assessing OM inputs to complex ecosystems.

Pollution generation in the Carajas region of Brazil: An extended input -output approach

The economic development of any region involves some consequences to the environment. The choice of a socially optimal development plan must consider a measure of the strategy's environmental impact. This dissertation tackles this problem by examining environmental impacts of new production activities. The study uses the experience of the Carajás region in the north of Brazil. This region, which prior to the 1960's was an isolated outpost of the Amazon area, was integrated to the rest of the country with a non-sophisticated but strategic road system and eventually became the second largest iron ore mining area in the world. Finally, in the 1980's, the area was linked, by way of a railroad, to the nearest seaport along the Atlantic Ocean. The consequence of such changes was a burst of economic growth along the railroad Corridor and neighboring areas. In this work, a Social Accounting Matrix (SAM) is used to construct a 2-region (Corridor and surrounding area), fixed price, Computable General Equilibrium (CGE) Model to examine the relationship between production and pollution by measuring the different pollution effects of alternative growth strategies. SAMs are a very useful tool to examine the environmental impacts of development by linking production activities to measurable indices of natural resource degradation. The simulation results suggest that the strategies leading to faster economic growth in the short run are also those that lead to faster rates of environmental degradation. The simulations also show that the strategies that leads to faster rates of short run growth do so at the price of a rate of environmental depletion that is unsustainable from a long run perspective. These results, therefore, support the concern expressed by environmental economists and policy makers regarding the possible trade-offs between economic growth and environmental preservation. This stresses the need for a careful analysis of the environmental impacts of alternative growth strategies. ^

A software tool that generates symbolic model verifier (SMV) input language from a predicate transition net

The purpose of this research was to apply model checking by using a symbolic model checker on Predicate Transition Nets (PrT Nets). A PrT Net is a formal model of information flow which allows system properties to be modeled and analyzed. The aim of this thesis was to use the modeling and analysis power of PrT nets to provide a mechanism for the system model to be verified. Symbolic Model Verifier (SMV) was the model checker chosen in this thesis, and in order to verify the PrT net model of a system, it was translated to SMV input language. A software tool was implemented which translates the PrT Net into SMV language, hence enabling the process of model checking. The system includes two parts: the PrT net editor where the representation of a system can be edited, and the translator which converts the PrT net into an SMV program.

Orthogonal Frequency Division Multiplexing Based Air Interfaces and Multiple Input Multiple Output Techniques in Cooperative Satellite Communications for 4th Generation Mobile Systems

Recently, wireless network technology has grown at such a pace that scientific research has become a practical reality in a very short time span. One mobile system that features high data rates and open network architecture is 4G. Currently, the research community and industry, in the field of wireless networks, are working on possible choices for solutions in the 4G system. The researcher considers one of the most important characteristics of future 4G mobile systems the ability to guarantee reliable communications at high data rates, in addition to high efficiency in the spectrum usage. On mobile wireless communication networks, one important factor is the coverage of large geographical areas. In 4G systems, a hybrid satellite/terrestrial network is crucial to providing users with coverage wherever needed. Subscribers thus require a reliable satellite link to access their services when they are in remote locations where a terrestrial infrastructure is unavailable. The results show that good modulation and access technique are also required in order to transmit high data rates over satellite links to mobile users. The dissertation proposes the use of OFDM (Orthogonal Frequency Multiple Access) for the satellite link by increasing the time diversity. This technique will allow for an increase of the data rate, as primarily required by multimedia applications, and will also optimally use the available bandwidth. In addition, this dissertation approaches the use of Cooperative Satellite Communications for hybrid satellite/terrestrial networks. By using this technique, the satellite coverage can be extended to areas where there is no direct link to the satellite. The issue of Cooperative Satellite Communications is solved through a new algorithm that forwards the received data from the fixed node to the mobile node. This algorithm is very efficient because it does not allow unnecessary transmissions and is based on signal to noise ratio (SNR) measures.

On the accuracy of nonsurvey regional input-output multipliers : An empirical study

Correct specification of the simple location quotients in regionalizing the national direct requirements table is essential to the accuracy of regional input-output multipliers. The purpose of this research is to examine the relative accuracy of these multipliers when earnings, employment, number of establishments, and payroll data specify the simple location quotients. For each specification type, I derive a column of total output multipliers and a column of total income multipliers. These multipliers are based on the 1987 benchmark input-output accounts of the U.S. economy and 1988-1992 state of Florida data. Error sign tests, and Standardized Mean Absolute Deviation (SMAD) statistics indicate that the output multiplier estimates overestimate the output multipliers published by the Department of Commerce-Bureau of Economic Analysis (BEA) for the state of Florida. In contrast, the income multiplier estimates underestimate the BEA's income multipliers. For a given multiplier type, the Spearman-rank correlation analysis shows that the multiplier estimates and the BEA multipliers have statistically different rank ordering of row elements. The above tests also find no significant different differences, both in size and ranking distributions, among the vectors of multiplier estimates.