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101.
J. Ignacio Criado Rodrigo Sandoval-Almazan J. Ramon Gil-Garcia 《Government Information Quarterly》2013
Social media in government is becoming one of the major trends in Electronic Government (e-government) research and practice worldwide. During the last few years, several authors have addressed the potential of social media for the innovation of public sector organizations. Most of these contributions have focused on the technical dimensions of social media, while other aspects have not attracted equal attention. In contrast, this introductory article interrogates the role of social media in the basic areas of e-government: government information flows and the availability of government information; the use of information technology to create and provide innovative government services; the impact of information technology on the relationships between the governed and those governing; and the increasing importance of information policies and information technologies for democratic practices. Accordingly, the next few pages propose and develop three dimensions of social media in government: tools, goals, and topics. We think that these dimensions could help to better understand the use of social media in government settings. Then, after a brief review of current trends in social media and government research, we present the articles included in this special issue. Finally, we present some practical lessons and suggest ideas for future research. This special issue could be seen as a starting point for the development of innovation through social media in public administrations around the world. 相似文献
102.
This paper reports a classroom-based study involving investigation activities in a university numerical analysis course. The study aims to analyse students' mathematical processes and to understand how these activities provide opportunities for problem posing. The investigations were intended to stimulate students in asking questions, to trigger their thinking processes, to promote their ability to investigate and to support them in learning numerical analysis' concepts and procedures. The results show that the investigations provided opportunities for students to experience mathematical processes, including posing questions, formulating and testing conjectures and, to some extent, proving results. They also provide some understanding about the role of problem posing in these processes. Posing questions occurred mainly in an implicit way, in the interpretation of tasks and in identifying regularities, analysing graphs and testing cases. The conjectures were often based on pattern identification or data manipulation, and the students tended to accept them without testing or proving. The students also proposed alternative formulations for the initial questions and posed new problems from their explorations and attempts to refine previous conjectures. 相似文献
103.
王四达 《华侨大学学报(哲学社会科学版)》2000,(2):91-96
章首先对《光明之城》的真伪问题提出鉴别标准,认为在英译未能提供原件作科学鉴定的情况下,仅以书中有某些符合历史的事例证其“不是伪书”是不可靠的,只有通过反向求证,考察书中是有不符合史实的事例才是更有效的鉴别方法。章随后对书听若干问题逐一考证,认为它们在着明显的错误和偏差。把它看作“伪书”是比较慎重的。 相似文献
104.
105.
THE POLYMERIZATION OF METHYL METHACRYLATE WITH A NEW TIN-BRIDGED YTTROCENE/Al(i-Bu)_3 总被引:1,自引:0,他引:1
INTRODUCTIONSincethepolymerizationofmethylmethacrylate(MMA)withrareearthcatalystswasrealizedforthefirsttimein1991,aseriesofnewrareearthcatalystsystemssuchasNd(P204)3/Al(iBu)3,Nd(P204)3/Al(iBu)3/CCl4,Nd(Oct)3/Al(iBu)3,Ln(acac)3/BuMgCl,Y(acac)3/Al(iBu)3/BuLi,Nd(naph)3/BuLi,andNd(O… 相似文献
106.
107.
This paper presents data from Brazilian Patent Office (Instituto Nacional de Propriedade Industrial, INPI) and compares them with data from the United States Patent Office (USPTO). Developing countries have technological activities that are important locally but not significant at international level (imitation, local learning, adaptation of foreign innovations). These activities might be patentable only at national level. Therefore, the study of domestic patents of developing countries provides a broader picture than USPTO patents. This paper compares 8309 INPI patents with 475 USPTO patents (between 1980 and 1995). Domestic patent data show peculiarities in the Brazilian case, possibly shared with other countries in similar technological level: (a) high share of individual patents; (b) foreign-owned firms with important activities; (c) low firm involvement in R&D activities. Some characteristics are shared with developed countries: (a) domestic firms as the major patentees; (b) according to firm size, there is a U-shaped distribution of patents; (c) evidences of multi-technology large firms; (d) a relatively small share of firms have more than one patent in the whole period. The contrast between USPTO and national patenting statistics shows different rankings according to ownership structure, leading firms, industrial sectors, and international patent classification. These differences highlight sources of international competitiveness and point to weaknesses in Brazilian innovative activities. This paper concludes evaluating the contributions (and weaknesses) of this database for the evaluation of the Brazilian National System of Innovation. 相似文献
108.
109.
Rodrigo Ramirez-Campillo Javier Sanchez-Sanchez Blanca Romero-Moraleda Javier Yanci Antonio García-Hermoso Filipe Manuel Clemente 《Journal of sports sciences》2020,38(13):1475-1487
ABSTRACT To assess the effects of plyometric jump training (PJT) in female soccer player’s vertical jump height, a review was conducted using the data sources PubMed, MEDLINE, Web Of Science and SCOPUS. Only peer-review articles were included. To qualify for inclusion in the meta-analysis, studies must have included (i) a PJT programme of at least 2 weeks, (ii) cohorts of healthy female soccer players with no restriction for age, (iii) a control group, (iv) a measure of countermovement jump (CMJ). The inverse variance random-effects model for meta-analyses was used. From 7,136 records initially identified through database searching, 8 were eligible for meta-analysis, comprising 9 training groups (n = 99) and 9 control groups (n = 94). The magnitude of the main effect was moderate (ES = 1.01 [95%CI = 0.36–1.66], Z = 3.04, p = 0.002). Sub-group analyses were performed (i.e., PJT frequency, duration and total number of sessions), revealing no significant subgroup differences (p = 0.34–0.96). Among the studies included in this review, none reported injury or other adverse effects. In conclusion, PJT is effective in female soccer players for the improvement of vertical jump height. In future, research must identify specific dose–response relationships following PJT, particularly in the long term. 相似文献