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排序方式: 共有370条查询结果,搜索用时 203 毫秒
1.
Alexander J.A.M. van Deursen Jan A.G.M. van Dijk Peter M. ten Klooster 《Telematics and Informatics》2015
We investigate types of Internet activities among a representative sample of the Dutch population from 2010 to 2013. We examined usage patterns of seven types of Internet activities (i.e., information, news, personal development, commercial transaction, social interaction, leisure, and gaming) and related these patterns with gender, age, education, and income. Activities related to news, personal development, commercial transaction, and social interaction increased in popularity. For most capital enhancing activities, men, younger people, higher educated people, and people with higher than average incomes were prominent. These observations, however, are subject to change. The Internet seems to provide increasingly more capital-enhancing opportunities for those with higher education and income, which would accordingly reinforce their already strong positions in society. 相似文献
2.
Abstract. This article analyses participation in the annual European congresses of the Regional Science Association (ERSA) from 1998 through 2003. We formulate goals that the ERSA conferences should aim at and based on these aims we formulate hypotheses about conference participation. In the empirical part we test hypotheses with regard to the spatial distribution of the participants over countries, the distribution of the frequency of attendance among the participants, and the presence of distance decay in participation. All hypotheses are confirmed. We also pay attention to the relation between the frequency of attendance and distance. In the conclusions we derive implications for future conferences. 相似文献
3.
Lisa C. Morgans Sarah Bolt Elizabeth Bruno-McClung Lisa van Dijk Maria P. Escobar Henry J. Buller David C.J. Main Kristen K. Reyher 《Journal of dairy science》2021,104(2):2212-2230
Farmer-led, participatory approaches are being increasingly employed in agricultural research, with promising results. This study aimed to understand how a participatory approach based on the Danish stable schools could help to achieve practical, farmer-led changes that reduced reliance on antimicrobials in the UK. Five facilitated farmer action groups comprising 30 dairy farms across South West England met on farm at regular intervals between 2016 and 2018, and worked collaboratively within their groups to discuss how to reduce antimicrobial use. Qualitative data from group discussions and individual semi-structured interviews were collected and analyzed using thematic analysis to explore how the approach helped farmers address and deal with changes to their on-farm practices. Facilitator-guided reviews of antimicrobial use and benchmarking were carried out on each farm to assess any change in usage and help farmers review their practices. The pattern of antimicrobial use changed over the 2 yr of the study, with 21 participating farms reducing their use of highest-priority critically important antibiotics (6 farms were not using any of these critical medicines from the outset). Thirty practical action plans were co-developed by the groups with an average implementation rate of 54.3% within a year. All assessed farms implemented 1 recommendation, and many were still ongoing at the end of the study. Farmers particularly valued the peer-to-peer learning during farm walks. Farmers reported how facilitated discussions and action planning as a peer group had empowered them to change practices. Participants identified knowledge gaps during the project, particularly on highest-priority critically important antibiotics, where they were not getting information from their veterinarians. The study demonstrated that facilitation has a valuable role to play in participatory approaches beyond moderating discussion; facilitators encouraged knowledge mobilization within the groups and were participants in the research as well. Facilitated, farmer-led, participatory approaches that mobilize different forms of knowledge and encourage peer learning are a promising way of helping farmers to adapt and develop responsible practices. 相似文献
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S. I. Correia H. Pereira J. Silva-Correia C. N. Van Dijk J. Espregueira-Mendes J. M. Oliveira R. L. Reis 《Journal of the Royal Society Interface》2014,11(92)
Tissue engineering and regenerative medicine (TERM) has caused a revolution in present and future trends of medicine and surgery. In different tissues, advanced TERM approaches bring new therapeutic possibilities in general population as well as in young patients and high-level athletes, improving restoration of biological functions and rehabilitation. The mainstream components required to obtain a functional regeneration of tissues may include biodegradable scaffolds, drugs or growth factors and different cell types (either autologous or heterologous) that can be cultured in bioreactor systems (in vitro) prior to implantation into the patient. Particularly in the ankle, which is subject to many different injuries (e.g. acute, chronic, traumatic and degenerative), there is still no definitive and feasible answer to ‘conventional’ methods. This review aims to provide current concepts of TERM applications to ankle injuries under preclinical and/or clinical research applied to skin, tendon, bone and cartilage problems. A particular attention has been given to biomaterial design and scaffold processing with potential use in osteochondral ankle lesions. 相似文献
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Dijk Corine; Koenig Bryan; Ketelaar Tim; de Jong Peter J. 《Canadian Metallurgical Quarterly》2011,11(2):313
This study examined whether blushing after a sociomoral transgression remediates trustworthiness in an interdependent context. Participants (N = 196) played a computerized prisoner's dilemma game with a virtual opponent who defected in the second round of the game. After the defection, a photograph of the opponent was shown, displaying a blushing or a nonblushing face. In a subsequent Trust Task, the blushing opponent was entrusted with more money than the nonblushing opponent. In further support of the alleged remedial properties of the blush, participants also indicated that they trusted the blushing opponent more, expected a lower probability that she would defect again, and judged the blushing opponent more positively. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
8.
Van Dijk P. Van Meijl F. 《Components and Packaging Technologies, IEEE Transactions on》1999,22(1):47-52
Application of electronics in systems that are exposed to high vibratory and shock stresses requires the use of fretting protected electrical connections. Fretting corrosion is caused by a relative motion of mated contact surfaces and results in contact failures. This paper presents a design concept that eliminates the relative motion at the contact point by introducing an additional elastic element. When the male half of a connector assembly moves relative to the female half, the contact regions on the male and female contacts will move some distance together before they start slipping. The onset of slip is predictable and measurable. This paper discusses the formula that determines the limit from where slip starts to occur. Also discussed are the effects of connector and application parameters such as coefficient of friction, normal force, spring rate, size of displacement, and lubrication. Evidence is presented that confirms the validity of the approach. The AMP Micro-MaTch contact system is used as example. Two statements about fretting were verified extra to confirming the validity of the approach. The first is that a small motion is worse than a large motion. The second that unplated phosphor-bronze behaves better than tinplated phosphorbronze. Unplated phosphor-bronze was also tested with anti-fretting lubricant and showed very good performance 相似文献
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10.
In the original Grover algorithm, an exact or almost exact search such that the success probability is unity or infinitesimally close to unity is possible only for certain values of the fraction λ = M/N where M is the number of marked items that are stored in an unsorted database of N items. There are various modified algorithms with an adjustable phase or phases such that an exact search can be done for any value of λ by means of a finite number of Grover-type operations. Among them, the algorithm proposed by Long is the simplest in the sense that it has only one adjustable phase and that the phase can be obtained in a closed form. We show that other more general algorithms with additional phases are not more efficient than Long’s version with a single phase. 相似文献