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121.
Thermodynamic principles are basic to an understanding of the complex fluxes of energy and information required to keep cells alive. These microscopic machines are nonequilibrium systems at the micron scale that are maintained in pseudo-steady-state conditions by very sophisticated processes. Therefore, several nonstandard concepts need to be taught to rationalize why these very ordered systems proliferate actively all over our planet in seeming contradiction to the second law of thermodynamics. We propose a model consisting of boxes with different shapes that contain small balls that are in constant motion due to a stream of air blowing from below. This is a simple macroscopic system that can be easily visualized by students and that can be understood as mimicking the behavior of a set of molecules exchanging energy. With such boxes, the basic concepts of entropy, enthalpy, and free energy can be taught while reinforcing a molecular understanding of the concepts and stressing the stochastic nature of the thermodynamic laws. In addition, time-related concepts, such as reaction rates and activation energy, can be readily visualized. Moreover, the boxes provide an intuitive way to introduce the role in cellular organization of "information" and Maxwell's demons operating under nonequilibrium conditions.  相似文献   
122.
Collaboration between Industry and University is becoming more important in order to improve the competitiveness of the research and development activities. Moreover, establishing synergies to bridge the gap between the academic and industrial spheres has demonstrated to be advantageous for both of them.

Nowadays, Industry is moving towards an open innovation structure, in which external agents as universities play a key role. Besides, University is also seeking a more active learning methodology to improve the education of students for the real world. Considering this framework, a special effort should be done to take advantage of the collaborative work between Industry and University.

The aim of this paper is to present the collaborative framework and the benefits obtained of the educational activities as a consequence of the long-term collaboration established between the University of Zaragoza and the Bosh and Siemens Home Appliances Group. The key stones of the collaboration are presented, and the positive outcomes for the students are highlighted. The strengths, weaknesses, opportunities, and threats of the proposed program are also discussed.  相似文献   

123.
We evaluate how far away six Latin American countries stand from a normative goal of equality of opportunity for educational achievement in PISA 2006–2009. We work with alternative characterizations of types: gender, school type (public or private), parental education, and their combinations. Following Checchi–Peragine's (2010) non-parametric method, we find that inequality of opportunity for educational achievement in Latin America ranges from less than 1% to up to 25%, depending on the year, the country, the subject and the specification of circumstances. These magnitudes are substantial with respect to what is found in comparator countries. Parental education and school type prove to be important sources of inequality of opportunity, contrary to gender. By means of sensitivity analyses, while most results show small to moderate variation in terms of magnitudes, in ordinal terms (rankings) they remain quite stable. Brazil stands out as the most opportunity-unequal country of the sample.  相似文献   
124.
PhD graduates hold the highest education degree, are trained to conduct research and can be considered a key element in the creation, commercialization and diffusion of innovations. The impact of PhDs on innovation and economic development takes place through several channels such as the accumulation of scientific capital stock, the enhancement of technology transfers and the promotion of cooperation relationships in innovation processes. Although the placement of PhDs in industry provides a very important mechanism for transmitting knowledge from universities to firms, information about the characteristics of the firms that employ PhDs is very scarce. The goal of this paper is to improve understanding of the determinants of the demand for PhDs in the private sector. Three main potential determinants of the demand for PhDs are considered: cooperation between firms and universities, R&D activities of firms and several characteristics of firms, size, sector, productivity and age. The results from the econometric analysis show that cooperation between firms and universities encourages firms to recruit PhDs and point to the existence of accumulative effects in the hiring of PhD graduates.  相似文献   
125.
The use of information and communication technologies has been a key strategy for government reform. It offers diverse benefits, ranging from efficiency and effectiveness to transparency and greater democratic participation. Governments in many parts of the world have invested vast resources into electronic government projects with the expectation of achieving these and other outcomes. However, the results in many cases are limited and there is no comprehensive way to evaluate these initiatives at the aggregate level. A method for measuring and evaluating electronic government that identifies its advances and problems is needed. Previous efforts to do so are limited in terms of scope and dimensions being considered. Based on a review of current literature and the analysis of international best practices, this paper proposes a multidimensional model for measuring and evaluating electronic government. It also includes examples, a proposal of how to operationalize it, and several recommendations for practical use.  相似文献   
126.
Social media such as blogs, microblogs or electronic social networks can transform the ways in which we relate to other people and organizations. Government organizations are experimenting with social media to communicate with their constituents, and many analysts see in these media a powerful set of tools to reinvent government–citizen relationships. In this paper, we present the perceptions of risks, benefits and strategic guidelines about social media applications gathered from 250 public servants from Central Mexico, most of them working in information technology, as web masters or responding to Freedom of Information Act requests. The conclusions of the analysis are 1) that governments' participation in social media may result in improved communication and citizen participation, more transparency, and transfer of best practices among government agencies; 2) that a good implementation strategy is necessary to realize these benefits and to avoid risks; and 3) that the implementation of social media highlights the importance of updating laws and regulations, and of promoting changes in government culture and organizational practices.  相似文献   
127.
This article provides a critical commentary on the concepts of representation and digital artefacts in Morgan and Kynigos’s article of this Special Issue. To set the context, in the first part, I examine some of the tensions that arose during discussions through the 1980s and 1990s about representation in mathematics education research. Then, I comment on the conceptual differences between Morgan’s and Kynigos’s approaches. These differences point to different epistemological assumptions that lead to different conceptualizations of artefacts in learning processes. In the last part, I argue that Morgan’s and Kynigos’s approaches have the merit of moving the discussion about representations to new theoretical horizons. I suggest, however, that a discussion about representations and digital artefacts requires a thematized account of the manner in which the phenomenological artefact- and representation-mediated knowledge produced by students in the classroom relates to the target cultural mathematical knowledge. Such an account, I contend, requires an explicit ontological conception of knowing and knowledge. I conclude the article with an example in which knowledge is considered as codified movement and knowing as the event of its enactment in concrete practice. Within this Hegelian materialist viewpoint, representations are neither predicated in terms of an adequacy between ideas and their representations nor as heuristic devices in meaning making processes. Representations are rather an integral part of the activity of knowledge presentation.  相似文献   
128.
Concerns regarding whether a sufficient supply of school psychologists exists have been evident for decades. Studies have predicted that school psychology would face a critical personnel shortage that would peak in 2010, but continue into the foreseeable future. The current study is a 10‐year follow‐up investigation based on previously published personnel shortage projections. Data derived from the National Association of School Psychologists 2009–2010 national study were used to examine current personnel shortages as well as to project the extent to which personnel shortages are likely to continue. Findings indicate that the field of school psychology continues to experience a personnel shortage that will continue through 2025. Additionally, greater rates of retirements are projected for the field for school psychologists who are males, who possess a doctoral degree, and for university faculty. Analyses based on the U.S. Census Regions indicate that notable differences are likely to occur in the match between the supply of and demand for school psychologists based on geographical location. Implications are discussed relating to the recruitment and retention of school psychologists and to the services they deliver.  相似文献   
129.
In the field of information retrieval (IR), researchers and practitioners are often faced with a demand for valid approaches to evaluate the performance of retrieval systems. The Cranfield experiment paradigm has been dominant for the in-vitro evaluation of IR systems. Alternative to this paradigm, laboratory-based user studies have been widely used to evaluate interactive information retrieval (IIR) systems, and at the same time investigate users’ information searching behaviours. Major drawbacks of laboratory-based user studies for evaluating IIR systems include the high monetary and temporal costs involved in setting up and running those experiments, the lack of heterogeneity amongst the user population and the limited scale of the experiments, which usually involve a relatively restricted set of users. In this paper, we propose an alternative experimental methodology to laboratory-based user studies. Our novel experimental methodology uses a crowdsourcing platform as a means of engaging study participants. Through crowdsourcing, our experimental methodology can capture user interactions and searching behaviours at a lower cost, with more data, and within a shorter period than traditional laboratory-based user studies, and therefore can be used to assess the performances of IIR systems. In this article, we show the characteristic differences of our approach with respect to traditional IIR experimental and evaluation procedures. We also perform a use case study comparing crowdsourcing-based evaluation with laboratory-based evaluation of IIR systems, which can serve as a tutorial for setting up crowdsourcing-based IIR evaluations.  相似文献   
130.
This article uses a case study to contribute to the debate on media-political clientelism and its relation to the theory of media systems. It proposes a cross-disciplinary approach between the fields of communication and political sciences and thus analyzes four dimensions to observe the evolution of these practices in the area of television policies during Spanish democracy: license granting, television ownership regulation, politicization of the public service, and partisan news coverage. The period analyzed includes conservative and social democrat governments, trying to find differences in clientelistic practices among the different political parties. The analysis demonstrates how partisan relationships have evolved and what mechanisms have been put in place to maintain clientelistic ties.  相似文献   
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