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71.
In the present qualitative research study, 35 Mac users were interviewed in a university campus that exclusively supports PC machines. We particularly explored the Mac-users’ social influences, saving technological and other influences for future reports. Results showed Mac users to possess significant connections with other Mac users on the university campus. The Mac users in our study indicated that positive, past exposure, including Apple’s advertising of Macs, had sharp influences on their decisions to become and remain Mac users. 相似文献
72.
73.
Abstract Increasing attention to watershed management is part of an international policy trend toward integrated water resource management. Integration is multidimensional—across sectors, administrative regions, ministerial portfolios and levels of hydrologic structure and socioeconomic organization. Collective action is key. Individuals need to work effectively together to share common water points; upstream land users and downstream water consumers need to manage and resolve potential conflicts over water quantity and quality, while all the industries, farming communities, urban residents and public agencies that have interests in resource use and environmental quality need to agree on development and conservation objectives and approaches at the basin level. Initiatives that seek to foster collective action in watersheds need to account for the very different interests in water and watershed management. While there may be relatively straightforward ways to foster collective action at a local scale, some forms of collective action may, in fact, be detrimental to other stakeholders. In the developing world in particular, there are often geographic pockets and social groups that are chronically disadvantaged in collective and public processes. Water-users' associations and basin authorities may exacerbate these disparities and further marginalize already poor people. New statutory institutions may intentionally or inadvertently disempower effective customary local institutions. To enable project and program designers to address these challenges better, this paper lays out a framework for assessing the potential for, and implications of, individual and collective decisions in a watershed context. The framework integrates concepts drawn from the biophysical and social sciences, including new perspectives on watershed components, poverty, and collective action. Collective action is seen as a fractal process: collective action for water management at one level of social-spatial organization can have spillover effects at lower and higher levels of social-spatial resolution. To be pro-poor, watershed-management institutions must be genuinely inclusive, deliberately recognizing the interests, perspectives and knowledge of groups that may be systematically excluded from other political and social processes. Researchers, evaluators, watershed-management practitioners and others who apply the framework should be better placed to lay the foundations for that illusive goal: pro-poor, inclusive and resource-conserving development. 相似文献
74.
This study examines the impacts of energy price changes resulting from different carbon-pricing policies on the competitiveness of selected US energy-intensive industries. It further examines possible industry responses, and identifies and provides a preliminary evaluation of potential opportunities to mitigate these impacts. The industry sectors investigated – steel, aluminum, chemicals and paper – are among the largest industrial users of fossil fuels in the US economy. The results of this examination show that climate policies that put a price on carbon could have substantial impacts on the competitiveness of US energy-intensive manufacturing sectors over the next two decades, if climate regulations are applied only in the United States, and no action is taken to invest in advanced low- and no-carbon technologies. The extent of these impacts will vary across industries, depending on their energy intensities, the mix of energy sources they rely on and how energy is used in production activities (heat and power, feedstock). Of relevance is also the speed and rigor with which industries adopt new technologies and retire (or replace) old ones. Other factors affecting these impacts include an industry's vulnerability to foreign imports and its ability to pass through cost increases to its customers in the face of international market competition. 相似文献
75.
Ruth Spielman 《Urban Policy and Research》2013,31(2):31-33
There are moves in Victoria to centralise planning and reduce opportunities for public involvement. It is symptomatic of the nation turning outwards towards global activity and an emphasis on rational economic theory. It is argued that this is opposite to what is needed. Failure to get projects up and running is not the result of people or planning delaying decisions. It is the product of lackof strategic thinking, an important part of which is broadening, not narrowing the scope of ideas. Public involvement can and should affect public policy and decision making processes on significant issues. Examples of how communities have done this are discussed. 相似文献
76.
Stroebel RJ Scheitel SM Fitz JS Herman RA Naessens JM Scott CG Zill DA Muller L 《The Joint Commission journal on quality improvement》2002,28(8):441-450
BACKGROUND: Disease registries are powerful tools with the potential to transform the way chronic diseases are managed. To date, however, little work has been done to determine how to optimize the implementation of a chronic disease registry in practice. METHODS: Twenty-nine physicians and their nurse teams in a large community internal medicine practice participated in this 6-month prospective randomized trial in 2000. Teams were assigned to one of three implementation strategies using information from a diabetes registry. Process and outcome measures for diabetes management were analyzed. Process measures included the percentage of patients completing glycosylated hemoglobin (Hgb) testing within 6 months and low-density lipoprotein (LDL) testing within 12 months. Outcome measures included the percentage of patients with a glycosylated Hgb > 9.3% (equivalent to a HgbA1c > 8.0%), the percentage of patients with an LDL cholesterol > 130 mg/dl, and the percentage of patients with controlled blood pressure, defined as < 130/85 millimeters of mercury. Mean change in LDL and glycosylated Hgb values was also measured. RESULTS: Teams randomized to an intervention strategy that included direct letters to patients showed significant improvement across a number of measures. The improvement was most apparent among patients without recent testing or with poorly controlled disease. The two interventions that did not include direct patient letters resulted in limited improvement. DISCUSSION: Disease registries can be used to improve outcomes in the management of diabetes and other chronic diseases. Better outcomes were seen in patients who received letters based on registry-generated data. This strategy should be included as part of a comprehensive chronic disease management plan. Further refinements in the use of registries should result in further incremental improvement. 相似文献
77.
What is to our knowledge the first stimulated Brillouin scattering experiment using a high-power low-gain solar pumped laser is presented. A threshold reflectivity of 0.23% was reached when a peak power of 20.7 kW was used at 7.6 GHz. A cw solar pumped laser was Q-switched with an acousto-optic modulator, and the bandwidth was narrowed with an intracavity etalon. A high polarization ratio (>99.4%) was achieved by use of an intracavity configuration. Higher reflectivity values were limited because of the lack of availability of optical switches. 相似文献
78.
Abstract. Past research indicates that expectations play a crucial role in the final satisfaction of users of information systems (IS). This includes expectations regarding the skill levels exhibited by the providers of the IS services and products. Typically, the expectations are examined as gaps from perceived performance or as gaps from realistic expectations. The interaction of these gaps has not been thoroughly explored in past research, although recent theories anticipate both gaps are crucial in meeting the desires of the users. A matched pair sample of IS users and IS providers is used to collect data on expected skill levels and perceived delivery of the skills demanded. Gaps, both between these two stakeholder groups regarding expectations and within the user group regarding perceived delivery, are found to impact user satisfaction in a two-way analysis. The results indicate that expectations should be managed to higher levels and commonly understood across the user and provider groups. 相似文献
79.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
80.
Joan Moss Ruth Beatty 《International Journal of Computer-Supported Collaborative Learning》2006,1(4):441-465
While it has been suggested that patterning activities support early algebra learning, it is widely acknowledged that the
shift from perceiving patterns to understanding algebraic functions—and correspondingly, from reporting empirical patterns
to providing explanations—is difficult. This paper reports on the collaborations of grade 4 students (n = 68) from three classrooms in diverse urban settings, connected through a knowledge-building environment (Knowledge Forum),
when solving mathematical generalizing problems as part of an early algebra research project. The purpose of this study was
to investigate the underlying principles of idea improvement and epistemic agency and the potential of knowledge building—as
supported by Knowledge Forum—to support student work. Our analyses of student-generated collaborative workspaces revealed
that students were able to find multiple rules for challenging problems and revise their own conjectures regarding those rules.
Furthermore, the discourse was sustained over 8 weeks and students were able to find similarities across problem types without
the support of teachers or researchers, suggesting that these grade-4 students had developed a disposition for evidence use
and justification that eludes much older students. 相似文献