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941.
What role can information science play in promoting public understanding of science and technology? In order to answer this question, it is important to understand the new perspective which is emerging for research in the information science field. Internet, and the information superhighways announced both in Europe and the United States, are increasingly focusing attention on computer‐mediated communication within research communities. “Collaboratories”; is the name given to work aimed at using computer‐based technologies to help promote the social processes of knowledge production. One goal of information science lies in efforts to measure the contribution of technical devices to knowledge production practices. This is called infometrics research; it requires a clear understanding of how the social system of science regulates information flows to promote these practices. 相似文献
942.
T Tsongas D Orlinskii I Priputina G Pleskachevskaya A Fetishchev G Hinman W Butcher 《Risk analysis》2000,20(1):73-79
A risk assessment was conducted to determine the likelihood of certain health risks resulting from exposure to soils and food crops contaminated with polychlorinated biphenyl (PCBs). PCBs have contaminated soils, river sediments, and air in the past as a result of industrial activities at a capacitor plant located in the City of Serpukhov, Russian Federation. This risk assessment and suggestions for remediation are designed to aid in decision-making efforts by a joint Russian-American research team developing a community, national, and international response to industrial contamination. Bobovnikova et al. (The Science of the Total Environment 139/140, 357-364, [1993]) have reported that PCBs are elevated in soils and sediments, breast milk, and locally grown foods in the Serpukhov area. Data from these and other investigators have been used in this risk assessment to calculate a potential cancer risk resulting from exposure to PCBs. Our assessment indicates that members of the local population may be at increased risk of cancer, and possibly other adverse health effects, as a result of PCB contamination of their environment. Because previously unassessed environmental contamination is a common problem in the former Soviet Republics, as well as many other areas of the world, we believe this type of evaluation, using known methods, can serve as a model for assessment efforts in other parts of the globe and result in remediative efforts in regions constrained by faltering economies. 相似文献
943.
Catherine H. Stein Erica Hoffmann Erin E. Bonar Jaclyn E. Leith Kristen M. Abraham Alexis C. Hamill Shane W. Kraus Shinakee Gumber Wendy R. Fogo 《Journal of Family and Economic Issues》2013,34(2):200-210
Using a sample of 222 young adults attending college, the present study examined the relative contribution of young adults’ perceived economic pressures, financial coping and religious meaning-making coping strategies in accounting for variation in their reports of psychological well-being within the context of the United States economic crisis. Results suggest a direct relationship between perceived economic pressure and psychological well-being such that young adults who reported having to make more economic adjustments as a result of economic crisis also reported higher levels of depressed mood and anxiety. Young men and women who reported having to make fewer economic adjustments and being able to meet their material needs reported higher levels of life satisfaction. Regardless of young adults’ self-reported level of economic pressures, the use of education and communication financial coping strategies was related to lower levels of self-reported anxiety and depressed mood and greater life satisfaction. Viewing the financial crisis as a punishment from God was generally associated with young adults’ reports of greater depressed mood and less life satisfaction. Implication of findings for research and practice are discussed. 相似文献
944.
Approximated QDF misclassification probabilities have been derived for bivariate normal populations with known parameter values. Tne effect of unequal covariances and population distance on the misclassification probabilities are examined 相似文献
945.
Allan W. Gregory 《商业与经济统计学杂志》2013,31(1):107-115
In this article we propose a nonparametric test for autoregressive conditional heteroscedasticity based on finite-state Markov chains. A simple Monte Carlo experiment suggests that in finite samples it performs comparably to the Lagrange multiplier test under conditional normality and is superior for the t, lognormal, and exponential distributions. As an illustration, we apply both tests to Canadian/U.S. forward foreign exchange data. 相似文献
946.
The lack of an adequate measure of perceived sources of stress for student nurses led to the construction of the Student Nurse Stress Index (SNSI). Responses from 235 first-year student nurses to 35 items from the Beck and Srivastava Stress Inventory (Beck, and Srivastava, 1991), and 15 new items, were subjected to exploratory factor analysis using principal components analysis and oblimin rotation. A reliable 22-variable solution with a simple oblique structure including Academic load, Clinical sources, Interface worries, and Personal problems factors was obtained in this initial sample, and confirmed at an exploratory level in a further independent validation sample of 188 first-year students. Confirmatory factor analysis established the four-factor model in the first sample, but required that three variables load onto more than one factor. This more complex four-factor model was confirmed using independent data from the validation sample, and the total invariance of factor loadings and factor covariances of this more complex four-factor model was established in both data sets simultaneously using multi-sample techniques. The SNSI shows cross-sample factor congruence, good internal reliabilities, and concurrent and discriminant validity across a range of reporting conditions. 相似文献
947.
We consider nonlinear and heteroscedastic autoregressive models whose residuals are martingale increments with conditional distributions that fulfil certain constraints. We treat two classes of constraints: residuals depending on the past through some function of the past observations only, and residuals that are invariant under some finite group of transformations. We determine the efficient influence function for estimators of the autoregressive parameter in such models, calculate variance bounds, discuss information gains, and suggest how to construct efficient estimators. Without constraints, efficient estimators can be given by weighted least squares estimators. With the constraints considered here, efficient estimators are obtained differently, as one-step improvements of some initial estimator, similarly as in autoregressive models with independent increments. 相似文献
948.
Raymond W. Carlson 《Journal of Social Work Education》2013,49(3):17-24
Rapid expansion of educational research and conceptualization combined with increased emphasis on relevance and effectiveness as values within the educational institution encourage expansion of the assumptions made by social work educators. Such expansion forces recognition of the complexity of the educational transaction and of the importance of flexibility as a teacher characteristic. But certain new assumptions suggest undeveloped opportunities for facilitating significant student learning. This article identifies four such opportunities based on assumptions about individual differences, cognitive functioning, and affective learning. A complex, growth-oriented view of social work education is emphasized. 相似文献
949.
950.
Public perceptions of carbon capture and sequestration (CCS) and other low‐carbon electricity‐generating technologies may affect the feasibility of their widespread deployment. We asked a diverse sample of 60 participants recruited from community groups in Pittsburgh, Pennsylvania to rank 10 technologies (e.g., coal with CCS, natural gas, nuclear, various renewables, and energy efficiency), and seven realistic low‐carbon portfolios composed of these technologies, after receiving comprehensive and carefully balanced materials that explained the costs and benefits of each technology. Rankings were obtained in small group settings as well as individually before and after the group discussions. The ranking exercise asked participants to assume that the U.S. Congress had mandated a reduction in carbon dioxide emissions from power plants to be built in the future. Overall, rankings suggest that participants favored energy efficiency, followed by nuclear power, integrated gasification combined‐cycle coal with CCS and wind. The most preferred portfolio also included these technologies. We find that these informed members of the general public preferred diverse portfolios that contained CCS and nuclear over alternatives once they fully understood the benefits, cost, and limitations of each. The materials and approach developed for this study may also have value in educating members of the general public about the challenges of achieving a low‐carbon energy future. 相似文献