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171.
This study investigates whether perceptions of the media and the public are related to political participation in Colombia. Communication researchers have built a large body of literature on hostile media perceptions and the projection effect, respectively. This study links these perceptual effects with each other and with political participation. Analyzing survey data from a representative sample of Colombian adults in urban areas, we show a direct relationship between hostile media perceptions and participation but no direct relationship between projection and participation. Hostile media perceptions and projection are negatively related. Results suggest that perceived media bias attenuates projection but increases political engagement.  相似文献   
172.
Word reading fluency is a key component in the process of reading. In order to understand its acquisition it is crucial to conduct longitudinal studies. The aim of this work was to describe the development of word recognition in Spanish, considering accuracy and speed, from a longitudinal perspective. A group of 31 children were followed for six years. Reading performance was assessed with a list of 72 stimuli in which lexicality, frequency and length were manipulated. Results show that initial gains in reading accuracy occurred very rapidly. However, the growth of reading speed was found to be more difficult and complex, and automatic word recognition remains low at the end of Grade 6. Low frequency, long words were the most difficult stimuli. High stability in reading speed was observed and it was a relevant indicator that differentiates between good and poor readers. The findings also highlighted the need to develop training programs with the specific aim of improving word reading fluency throughout primary education.  相似文献   
173.
In teaching introductory quantitative methods in sociology, I have used a controversial survey of mortality in Iraq before and after the 2003 invasion to highlight to students the power of simple questionnaires, the role of ambiguity in statistics and the place of politics in the framing of statistical results. This brief report summarizes Roberts et al.'s (2004) estimate that the invasion of Iraq resulted in 98,000 (95% CI = 8000–194,000) deaths, as well as the intriguing reaction that the survey received in the press. Statistics teachers should find the Roberts et al. study to be an effective way to introduce students to more controversial – and political – aspects of statistical research.  相似文献   
174.
This paper relates and analyses the experience of various Brazilian institutions organized in a consortium with the aim of providing integration and unified access, via a web gateway, to full-text electronic theses already available at different Brazilian universities. The rise and impact of free electronic academic publishing on scientific communication and the development of science is analyzed. The results of a pilot programme, developed under the coordination of IBICT, as well as technical and technological aspects of information system models adopted, are presented. Aspects such as metadata sets and formats, protocols for automatic gathering of metadata, union catalogue databases, user interfaces and integration with other Brazilian STI systems, are analyzed. Finally, future developments and the enlargement of the Brazilian Digital Library of Theses and Dissertations are discussed.  相似文献   
175.
The Spanish pharmaceutical industry underwent an important transformation during the 1990s. To survive under the new market conditions, labs had to refocus their competitive strategies towards increasing productive efficiency or reinforcing research and development (R&D) activities. This paper analyzes the evolution of the productive patterns in a sample of 80 pharmaceutical laboratories that operated in Spain from 1994 to 2000. We estimate Malmquist productivity indexes and decompose them into four sources of productivity change. The results suggest that pure technical efficiency change and the scale change of the technology explain most of the productivity growth observed during the period. The contribution of technical change to productivity growth is negligible, indicating a poor result from R&D activities at least in the groups of Small and Medium-sized labs.  相似文献   
176.
In this paper, inverse optimal neural control for trajectory tracking is applied to glycemic control of type 1 diabetes mellitus (T1DM) patients. The proposed control law calculates the adequate insulin delivery rate in order to prevent hyperglycemia and hypoglycemia levels in T1DM patients. Two models are used: (1) a nonlinear compartmental model in order to obtain type 1 diabetes mellitus virtual patient behavior, and (2) a neural model obtained from an on-line neural identifier, which uses a recurrent neural network, trained with the extended Kalman filter (EKF); the last one allows the applicability of an inverse optimal neural controller. The proposed algorithm is tuned to track a desired trajectory; this trajectory reproduces the glucose absorption of a healthy person. The applicability of the proposed control scheme is illustrated via simulations.  相似文献   
177.
The purpose of this study was to analyze pedaling cadence, pedal forces, and muscle activation of triathletes during cycling to exhaustion. Fourteen triathletes were assessed at the power output level relative to their maximal oxygen uptake (355 +/- 23 W). Cadence, pedal forces, and muscle activation were analyzed during start, middle, and end test stages. Normal and tangential forces increased from the start to the end of the test (-288 +/- 33 to -352 +/- 42 N and -79 +/- 45 to -124 +/- 68 N, respectively) accompanied by a decrease in cadence (96 +/- 5 to 86 +/- 6 rpm). Muscle activation increased from the start to the middle and the end in the gluteus maximus (27 +/- 5.5% and 76 +/- 9.3%) and in the vastus lateralis (13 +/- 3.5% and 27 +/- 4.4%), similar increase was observed from the start to the end in the rectus femoris and the vastus medialis (50 +/- 9.3% and 20 +/- 5.7%, respectively). Greater normal force along with enhanced activation of knee and hip extensor muscles is linked with fatigue and declines in cadence of triathletes during cycling to exhaustion.  相似文献   
178.
179.
A usual strategy to implement CLIR (Cross-Language Information Retrieval) systems is the so-called query translation approach. The user query is translated for each language present in the multilingual collection in order to compute an independent monolingual information retrieval process per language. Thus, this approach divides documents according to language. In this way, we obtain as many different collections as languages. After searching in these corpora and obtaining a result list per language, we must merge them in order to provide a single list of retrieved articles. In this paper, we propose an approach to obtain a single list of relevant documents for CLIR systems driven by query translation. This approach, which we call 2-step RSV (RSV: Retrieval Status Value), is based on the re-indexing of the retrieval documents according to the query vocabulary, and it performs noticeably better than traditional methods. The proposed method requires query vocabulary alignment: given a word for a given query, we must know the translation or translations to the other languages. Because this is not always possible, we have researched on a mixed model. This mixed model is applied in order to deal with queries with partial word-level alignment. The results prove that even in this scenario, 2-step RSV performs better than traditional merging methods.  相似文献   
180.
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