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排序方式: 共有1063条查询结果,搜索用时 15 毫秒
981.
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David Turnbull Henry Krips Val Dusek Steve Fuller Alan Sokal Jean Bricmont Alan Frost Alan Chalmers Anna Salleh Alfred I. Tauber Yvonne Luxford Nicolaas Rupke Steven French Peter G. Brown Hugh LaFollette Peter Machamer Nicolas Rasmussen Andy J. Miller Marya Schechtman Ross S. West John Forge David Oldroyd Nancy Demand Darrin W. Belousek Warren Schmaus Sungook Hong Alan Chalmers Rachel A. Ankeny Peter Anstey Jeremy Butterfield Harshi Gunawardena 《Metascience》2000,9(3):347-498
983.
Before there was the digital divide there was the analog divide– and universal service was the attempt to close that analogdivide.
Universal service is becoming ever more complex in terms ofregulatory design as it becomes the digital divide. In order to
evaluatethe promise of the next generation Internet with respect to the digitaldivide this work looks backwards as well as
forwards in time. Byevaluating why previous universal service mechanisms failed andsucceeded this work identifies specific
characteristics ofcommunications systems – in particular in billing and managinguncertainty – and argues that these characteristics
underliesuccess or failure in terms of technological ubiquity. Developing a setof characteristics of services rather than
a set of services is afundamental break with the tradition of universal service. In fact, theimplications of our proposal
is that basic characteristics in theoffering of the service rather than the absolute price are critical toclose the digital
divide: certainty of total charge, ability to avoiddeposits or disconnection via best effort service, and payer-basedcontrol
of all charges. While all of these principles sound obvious infact none of these hold in the telephony network. Universal
service hasevolved from common carriage (serve all with no discrimination) to aright to basic services (100% penetration).
Universal service isnow discussed as the digital divide, as the access to information asopposed to services becomes increasingly
critical. However, we arediscussing in this paper access to the bits and the network rather thanaccess to the information
(or intellectual property) once connected. Theprovision of universal service is seen as a technical problem only in thatthe
technology costs money – universal service debates have longbeen the domain of economists. Yet the design of protocols has
been thedomain of engineers, the building of systems the corporate domain, andthe discussion of equity the interest of ethicists.
The design ofprotocols can define the parameters of the corporate decision-makers,the variables of the economist, and the
questions for the ethicist. Thedesign decisions made at the fundamental levels can make communicationsequity more or less
likely. In this work I focus on the design ofprotocols for the next generation Internet, protocols which willfundamentally
change the best-effort nature of Internet services.Building on the economic and ethnographic work of others I argue thatthe
effects of protocols adoption on universal service can be predictedto some degree. By examination of past and current technologies
Iexamine a set of technical mechanisms to determine how such mechanismsmight harm or enhance universal service. I define each
mechanism (e.g.denial of entry) and offer observations about each particularmechanism's implicit pricing assumptions. I close
with a discussion ofinterest to ethicists and regulators on evaluating communicationsprotocols with respect to universal access.
Protocols for developingmultiple qualities of service for packet-switched networks have focusedon economic efficiency (e.g.
Mackie-Mason, 1995; Choi, Stahl &Winston, 1997; Shapiro & Varian, 1998), billing to encouragewidespread adoption of network
innovations (e.g. Xie & Sirbu, 1985)and billing in a manner consistent with the underlying network (e.g.Clark, 1996). Here
we examine a set of protocols which include varyingquality of service mechanisms with respect to the compatibility of theprotocols
with universal access. 相似文献
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Covid-19 has spread globally, affecting all nations. Preventive measures were implemented by governments including the closure of universities. The aim of this study was to evaluate the student's perspectives and experiences on the shift to remote preclinical medical education while inquiring whether there has been any psychological impact on the students. A customized questionnaire utilizing Likert-scale-based questions and the Generalized Anxiety Disorder-7 assessment tool was distributed online to enrolled preclinical medical students at the Faculty of Medicine and Surgery at the University of Malta. Quantitative and qualitative analyses of the data gathered was carried out. Multivariate logistic regression analyses was performed to establish independent variables associated with anxiety symptoms. A total of 172 responded out of a cohort of 299 preclinical students (58%). The majority perceived a positive learning experience following the shift to remote lectures, however, it was not the case for small group teaching including dissection sessions. Nonetheless students reported concerns about their education, examinations, progression to next academic year and wellbeing. Less than half the students exhibited symptoms of anxiety. Students exhibiting “moderate” worry (OR:7.6; CI 95%:1.98–29.31; P < 0.01) and “severe” worry (OR: 2.0; CI 95%: 5.0–80.5; P < 0.01) on their mental, emotional, and wellbeing due to Covid-19 were associated with anxiety symptoms after adjusting for cofounders. Apart from the short-term effects, the Covid-19 pandemic may have a long-term impact on both the medical education and the students' future careers. It is important that the implemented changes in medical education are recorded and studied since such data will be essential on how to proceed post-Covid-19 pandemic. 相似文献
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