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Roy Kelly 《Public Budgeting & Finance》2000,20(4):36-51
Countries throughout Sub-Saharan Africa are exploring options to improve local property taxation. Using the case of Kenya, this article provides an analytical framework for designing an effective property tax reform strategy. The first section presents a general conceptual model of property tax revenues, identifying four critical ratios that ultimately determine the effectiveness of any property tax system—namely, the coverage ratio, the valuation ratio, the tax ratio, and the collection ratio. The second section applies this conceptual framework to the property tax system in Kenya, focusing on the status of these four ratios and outlining possibilities for improving each ratio. The article concludes by summarizing five basic lessons from the Kenyan analysis that can assist in the development of appropriate property tax reforms in other developing countries in Sub-Saharan Africa. 相似文献
167.
For many years, the U.S. Government has encouraged the transfer of technologies developed through taxpayer funded endeavors to the commercial sector of the U.S. economy. The Regional Technology Applications Board, based at NASA's Marshall Space Flight Center, is an organization with technology transfer responsibilities. The Board receives technology transfer assistance (TTA) requests from many private-sector firms. The Board relies heavily on a problem statement from the requestor of technology assistance in determining an appropriate solution to the requestor's needs. However, the problem statements contained in these requests are often vague, ambiguous, or repetitive. This study reports on a method developed to analyze and classify problem statements that have been received by the Board so that additional understanding of the nature of these problems is obtained. One thousand one hundred past problem statements were analyzed using a content analysis method. The hierarchical classification structure developed during this project includes classes, sub-classes, and sub-sub-classes, allowing for differentiation of problem statements based upon key elements contained within the statements. Previously, no method for analysis and classification of problem statements had been documented. The results of the study indicate that problem statements can be analyzed and classified. The problem statement classification structure created through this project provides a vehicle for problem statement assignment, thereby lending additional form to the problem definition process. The study also provides an understanding of the frequency and distribution of TTA problem statements received by the Board. 相似文献
168.
Kelly Brinsko-Beckert M.S. Christopher S. Palenik Ph.D. 《Journal of forensic sciences》2020,65(5):1480-1496
3D printers are becoming increasingly efficient and economical, and thus more widespread and easily accessible to consumers and businesses. They have been used to print nefarious objects such as guns and suppressors. Previous research has documented the release of dust particles during the printing process; however, little has been written about the morphology and chemical features that define the dust emitted by these printers. This study was undertaken to recover, analyze, and identify the dust produced during the printing process in the context of forensic trace evidence analysis. Samples were collected from a variety of 3D fused deposition modeler printers, representing both consumer and commercial grade models. This work focused on printers that use thermoplastic filaments composed of acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), two of the most commonly used filament polymers. Swabs were used to collect dust within the printer chamber and then processed to isolate the dust particles. Particles produced from ABS filaments are most easily recognized via light microscopy through a combination of color, morphology, and fluorescence. The composition of these particles can be confirmed through analysis by either FTIR or Raman microspectroscopy. These methods can also be used to identify ABS fillers and pigments within the printer dust particles. In contrast, dust from PLA printers consistently contained finer, submicron-sized particles that could be observed by field emission scanning electron microscopy. Because the size of the particles precludes their identification using vibrational spectroscopy methods, pyrolysis-GC-MS was used to confirm the presence of PLA. 相似文献
169.
David Schwartz Brynn M. Kelly Mylien T. Duong 《Journal of youth and adolescence》2013,42(9):1319-1330
Existing theoretical perspectives suggest that adolescents who are characterized by high achievement may experience social sanctions from peers. The central premise is that, in many North American settings, adolescent peer groups are characterized by negative attitudes toward the school environment. To test these hypotheses, we examined associations between indicators of low social power (unpopularity and victimization by peers) and academic competence for 415 adolescents (193 boys; 222 girls) attending an urban high school. This school served neighborhoods that were characterized by a moderate degree of economic distress and the students were predominately of Hispanic American descent. A short-term longitudinal design was used, with two waves of data collected over consecutive school years. The adolescents completed a peer nomination inventory assessing relational and overt victimization by peers, unpopularity, and social rejection. In addition, we obtained math and language arts grades from school records, and we assessed behavioral engagement in school with a self-report inventory. Structural equation models did not reveal a strong pattern of longitudinal change in social standing with peers or academic functioning. However, we found positive correlations between academic achievement and problematic peer relationships in both years of the project. We also found evidence that gender moderates these associations, with the effects reaching significance only for boys. Our results provide evidence that, in some settings, high achieving adolescents can be prone to negative treatment or marginalization by peers. 相似文献
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