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91.
92.
The aim of this article is to identify a technical domain of knowledge in the curriculum of the Swedish elementary school and views on elementary school technology of two interest groups – school teachers and engineers. Gradually during the early to mid‐1920s there was increased technical content in the Swedish elementary school, if we look at the new curriculum, in‐service education and stakeholders’ views. The main reasons for this were, first of all, that the first decades of the twentieth century witnessed industrial growth with accompanying technification of large parts of society including the school. Second, the curriculum of 1919 had a broader technical content than earlier curricula, and thus mirrored the societal changes. Third, vocational secondary schools led to new requirements in respect of elementary technology education. Representatives of the Government were prime movers in enhancing the significance of technology in school together with teachers, while engineers generally showed little interest.  相似文献   
93.
Historic buildings are important for cultural history and provide a variety of habitats for animals and plants. Especially structural heterogeneity of wall surfaces is perceived to support biological diversity. Nevertheless, in traditional approaches goals of biodiversity preservation and monument restoration are perceived to interfere and to be mutually exclusive. As a consequence, priority is often given to constructional restoration accepting the loss of local populations and biodiversity. At walls of medieval castles, including an experimental restoration project where conventional and less intensive restoration techniques were applied, we relate species composition and richness to wall properties. Especially wall surface structure is quantified using a novel approach. The study focuses on lichens, mosses and vascular plants. Boosted regression tree analyses and non-metric multidimensional scaling techniques are applied to detect the influence of abiotic site conditions on biodiversity. We find species richness to be promoted by wall surface heterogeneity. However, species composition is more affected by restoration approaches than species richness. Lichen composition varies considerably while vascular plants and mosses are less affected by wall properties. We suggest strategies that are combining both societal targets, the preservation of historic monuments and of species diversity. Careful restoration is capable of supporting both, the maintenance of cultural heritage and of rare and unique anthropogenic habitats. Wall surface heterogeneity needs to be witnessed for both aspects as it affects both species composition as well as the effectiveness of cleaning methods.  相似文献   
94.
While it has often been suggested that information and communication technologies (ICTs) provide an important means of increasing citizen participation (which is at the core of democratic government), few commentators have expected non-democracies to create online environments in which citizens can take an active part in political processes. In recent years, however, some non-democracies have begun to outperform countries with long-standing democratic traditions in terms of e-participation development. According to the 2010 United Nations (UN) e-government survey, Bahrain outranks France, Kazakhstan beats Sweden and Malaysia ranks higher than Germany. This article sets out to understand the recent rise of e-participation initiatives in non-democracies. Drawing on comparative longitudinal data from the UN e-government surveys, we tested the assertion that international drivers of change are competing with the dominant focus on domestic factors, especially in the non-democratic world, and are influencing the patterns of reform. The empirical analysis demonstrated important differences between the drivers of change in democratic and non-democratic countries and found economic globalization to be the strongest predictor of e-participation initiatives in non-democratic countries. In conclusion, we argue that economic globalization alters the context of e-participation and necessitates a re-examination of many of its premises and tenets.  相似文献   
95.
BackgroundPhysical activity is favorable for health, and vigorous sports activity is particularly beneficial. This study investigates the association between changes in sports participation patterns over time and cardio-metabolic and self-perceived health outcomes.MethodsData from 3752 adults (18–79 years of age) who participated in 2 national health interview and examination surveys in 1997–1999 and 2008–2011 were included, with a mean follow-up time of about 12 years. A change in self-reported sports activity was analyzed with respect to the incidence of type 2 diabetes, coronary heart disease (CHD), hypertension, obesity, dyslipidemia, metabolic syndrome, and poor self-perceived health. Participants with pre-existing disease or risk factor of interest at baseline were excluded from the analysis. Being sufficiently active in sports was specified as doing sports for at least 1–2 h per week, and 4 activity categories were defined: 1) inactive at both time points (inactive–inactive), 2) inactive at baseline and active at follow-up (inactive–active), 3) active at baseline and inactive at follow-up (active–inactive), and 4) active at both time points (active–active). Associations between sports activity engagement and health outcomes were estimated by logistic regression models with different stages of adjustments.ResultsNot engaging in any regular sports activity at both time points (inactive–inactive) was associated with higher rates of type 2 diabetes (odds ratio (OR) = 1.82, 95% confidence interval (95%CI): 1.08–3.08), CHD (OR = 1.82, 95%CI: 1.16–2.84), hypertension (OR = 1.36, 95%CI: 1.03–1.81), metabolic syndrome (OR = 1.58, 95%CI: 1.08–2.32), and poor self-perceived health (OR = 2.54, 95%CI: 1.83–3.53) compared to doing regular sports for a minimum of 1–2 h per week over time (active–active). In case of change from inactivity to any regular sports activity (inactive–active), the rate of risk factor occurrence was not statistically different from the active–active reference group except for poor self-perceived health, but it was higher for type 2 diabetes (OR = 2.15, 95%CI: 1.12–4.14) and CHD (OR = 1.77, 95%CI: 1.03–3.03). Being active at baseline but inactive at follow-up (active–inactive) was not associated with higher disease incidence of type 2 diabetes (OR = 0.70, 95%CI: 0.25–1.97) or CHD (OR = 1.20, 95%CI: 0.49–2.99), but was associated with higher rates of hypertension (OR = 1.61, 95%CI: 1.11–2.34), obesity (OR = 2.34, 95%CI: 1.53–3.57), metabolic syndrome (OR = 1.70, 95%CI: 1.11–2.63), and poor self-perceived health (OR = 2.16, 95%CI: 1.53–3.07) at follow-up.ConclusionEven a low weekly quantity (1–2 h) of regular sports activity is partly associated with health benefits. Being formerly but not currently active was not associated with an increased disease incidence, but was associated with a higher risk-factor development compared to the reference group (active–active). Becoming active was preventive for risk-factor development but was not preventive for disease incidence, which probably means that the health benefits from sports activity are not sustainable and disease incidence is only shifted to a later period in life. For this reason, the promotion of and commitment to regular sports activity should be addressed as early as possible over the lifespan to achieve the best health benefits.  相似文献   
96.
As freshmen in 1966, 26 students at a liberal arts college entered Program II, and experiment in individualized education which relieved them from usual collegiate requirements for all four years. Twelve years later, 22 of these participants, plus 19 nonparticipating classmates of 1970, were interviewed. Except for their evaluation of their college experience (Program II participants were more negative about it), participants and nonparticipants are indistinguishable on comparisons of post-graduate education, occupational history, family and residential patterns, leisure activities, and attitudes toward self.This research was supported by a grant from the Mellon Foundation.  相似文献   
97.
98.
数字黑洞   总被引:2,自引:0,他引:2  
本文分析了数字化项目的投资陷阱,从成本构成上阐述了容易被人忽视的持续性投入,提醒人们,如果预算中无法保障维护性费用的话,先期进行数字化的高昂投入也将前功尽弃。  相似文献   
99.
Mathematical word problems represent a common item format for assessing student competencies. Automatic item generation (AIG) is an effective way of constructing many items with predictable difficulties, based on a set of predefined task parameters. The current study presents a framework for the automatic generation of probability word problems based on templates that allow for the generation of word problems involving different topics from probability theory. It was tested in a pilot study with N = 146 German university students. The items show a good fit to the Rasch model. Item difficulties can be explained by the Linear Logistic Test Model (LLTM) and by the random-effects LLTM. The practical implications of these findings for future test development in the assessment of probability competencies are also discussed.  相似文献   
100.
SEAD method estimates the direction-of-arrival angles on an uniform linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.  相似文献   
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