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41.
42.
Endogenous technical advance and the stochastic trend in output: A neoclassical approach 总被引:2,自引:0,他引:2
In the recent endogenous growth literature, the trend in output is stochastic, while investment in scientific knowledge is treated as analogous to a capital stock. This paper models both research and development (R&D) and disembodied technical advance using neo-classical equations, which specify the equilibrium stocks as a function of prices and output. The elasticity of R&D in the production function, estimated using factor shares, is time-varying and increasing. Returns to scale are increasing in all factors. The most important aspect of the model is that the equilibrium rate of technical advance is not cyclically invariant, but co-moves with output at business cycle frequencies. This allows the production function to behave as a stochastic trend. Growth accounting demonstrates that long-term variations in the rate of productivity growth have been associated mainly with low-frequency fluctuations in the rate of disembodied technical advance, with secondary effects from the stocks of R&D and physical capital. During the high productivity period 1948–1972, technical advance contributed 1.48 percentage points per year to output, with 0.98 accounted for by R&D. The productivity slowdown of the mid-1970s was accounted by a gradual decline in the effect of R&D, and a more abrupt collapse in disembodied technology. The subsequent productivity revival was associated with two accelerations in disembodied technical advance, the first beginning in the early 1980s, and the second in the mid-1990s. The production function is simulated in a small econometric model. Model simulations find that exogenous shocks to the inflation rate generate significant variations in growth by inducing fluctuations in disembodied technology. 相似文献
43.
Gauchat G 《Public understanding of science (Bristol, England)》2011,20(6):751-770
Using the National Science Foundation's 2006 Science Indicators Survey, this study explores three distinct explanations of public attitudes. First, the knowledge-attitudes model refers to a well tested relationship between public knowledge of science and more favorable attitudes toward science. Second, the alienation model hypothesizes that public disassociation with science is a symptom of a general disenchantment with late modernity, mainly, the limitations associated with codified expertise, rational bureaucracy, and institutional authority. A third approach emphasizes the cultural meaning of science: how various public beliefs about "what science is" relate to acceptance or reservations about science. The Science Indicators Survey shows that US adults view science (what it is or should be) in three distinct ways: (1) in terms of having a systematic method, (2) in terms of social location (i.e., takes place in a university or a laboratory), and (3) in terms of knowledge that should accord with commonsense and tradition. The findings in this study indicate that the knowledge-attitudes, alienation, and cultural meanings models are all valuable for understanding the cultural authority of science. However, the strength of these explanations depends on the type of attitude analyzed. 相似文献
44.
Gordon Hull Heather Richter Lipford Celine Latulipe 《Ethics and Information Technology》2011,13(4):289-302
Social networking sites like Facebook are rapidly gaining in popularity. At the same time, they seem to present significant
privacy issues for their users. We analyze two of Facebooks’s more recent features, Applications and News Feed, from the perspective
enabled by Helen Nissenbaum’s treatment of privacy as “contextual integrity.” Offline, privacy is mediated by highly granular
social contexts. Online contexts, including social networking sites, lack much of this granularity. These contextual gaps
are at the root of many of the sites’ privacy issues. Applications, which nearly invisibly shares not just a users’, but a
user’s friends’ information with third parties, clearly violates standard norms of information flow. News Feed is a more complex
case, because it involves not just questions of privacy, but also of program interface and of the meaning of “friendship”
online. In both cases, many of the privacy issues on Facebook are primarily design issues, which could be ameliorated by an
interface that made the flows of information more transparent to users. 相似文献
45.
Michelle D. Lazarus Gordon L. Kauffman Jr. Milind J. Kothari Timothy J. Mosher Matthew L. Silvis John R. Wawrzyniak Daniel T. Anderson Kevin P. Black 《Anatomical sciences education》2014,7(5):379-388
Current undergraduate medical school curricular trends focus on both vertical integration of clinical knowledge into the traditionally basic science‐dedicated curricula and increasing basic science education in the clinical years. This latter type of integration is more difficult and less reported on than the former. Here, we present an outline of a course wherein the primary learning and teaching objective is to integrate basic science anatomy knowledge with clinical education. The course was developed through collaboration by a multi‐specialist course development team (composed of both basic scientists and physicians) and was founded in current adult learning theories. The course was designed to be widely applicable to multiple future specialties, using current published reports regarding the topics and clinical care areas relying heavily on anatomical knowledge regardless of specialist focus. To this end, the course focuses on the role of anatomy in the diagnosis and treatment of frequently encountered musculoskeletal conditions. Our iterative implementation and action research approach to this course development has yielded a curricular template for anatomy integration into clinical years. Key components for successful implementation of these types of courses, including content topic sequence, the faculty development team, learning approaches, and hidden curricula, were developed. We also report preliminary feedback from course stakeholders and lessons learned through the process. The purpose of this report is to enhance the current literature regarding basic science integration in the clinical years of medical school. Anat Sci Educ 7: 379–388. © 2014 American Association of Anatomists. 相似文献
46.
Michelle Gordon Allison Haack Rebecca Vernon Tiffany Saulter Debora Shaw 《Public Library Quarterly》2014,33(2):145-154
How do public libraries develop their collections of high-demand materials for the “I want it now” generation? Ten public libraries’ holdings of fiction and nonfiction bestseller titles were observed over a four-week period. The number of copies rose fairly consistently, with the five fiction titles having roughly about twice the number of copies as the five nonfiction titles. The ratio of holds to copies averaged 2.7:1 and ranged from 0.8:1 to 6.5:1. Demand for e-books was consistently higher than the number of copies available, averaging more than 4:1 across all libraries. 相似文献
47.
48.
This study compares the instrumentation and analysis techniques used when determining the power expended pedalling a rope-braked
ergometer manufactured by Monark (Sweden) during a low intensity test. Power values were generated by eight subjects. The
instrumentation consisted of load cells to measure the rope brake forces, a tachometer to measure the flywheel velocity and
instrumented pedal cranks manufactured by Schoberer Rad Messtechnik (SRM). The subjects pedalled a rope-braked ergometer at
60 rev min-1, against a resistance of 3 kg, for 5 minutes. Three different measurements of the mean power were recorded and these were
compared with the value given by Monark. The SRM cranks provided two sets of results using different software packages supplied
with the cranks. SRM standard software is used for taking measurements during training and cycle races over long time periods.
An additional piece of software is provided by SRM called Ptnew, which gives readings of torque and pedal cadence over periods
up to 30 seconds. Using the values supplied by Monark each subject generated 180 W of power. The mean power for the eight
subjects, measured using the SRM cranks, was 170.36 W (SD 4.11) using the alternative SRM software (Ptnew) over a 30 second
period and 173.68 W (SD 2.21) using the standard SRM software. From the direct measurement of the brake forces and flywheel
velocity the mean power across the eight subjects was 148.90 W (SD 5.89). The SRM cranks measure the input power, whereas
the direct measurement system measures the power output excluding mechanical losses. These values give a figure for the mechanical
efficiency for the roped-braked ergometer of 88%. It was found that Monark overestimates the power generated by the subjects
when compared with both the SRM systems and the direct measurement instrumentation. 相似文献
49.
50.
Gordon E Finley 《Int J Intercult Relat》1979,3(1):5-13
Although the topic of research collaboration receives infrequent comment, a well functioning collaborative process is crucial to the substantive success of intercultural research enterprises. The present report addresses this topic and focuses on two major sets of collaborative issues, the personal/ personnel and the structural/organizational. The issues are organized around the phases of the project at which they optimally should be considered and resolved. 相似文献