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91.
Susan Riley 《金卡工程》2001,(8):34-35,33
目前,评测超5类结构化布线系统的标准,都记录在2000年1月发行的TIA/EIA(电信工业协会/电子工业联合会)568A-5当中。6类系统的标准应在一年左右得到认可。 近来,各公司都开始提出,要想真正得到一个确保网络最大效率的结构化布线系统,唯一的方法就是选择那些在有源信道中经过独立测试的产品, 相似文献
92.
J. L. Bencze 《International Journal of Technology and Design Education》2001,11(3):273-298
The status quo for school science and technology is unacceptable. While the former often is required for admission to university engineering,
as well as to science programmes, the latter is deemed most appropriate for less able, concrete thinkers. This situation persists,
despite the fact school science tends to generate large groups of citizens who are relatively scientifically and technologically
illiterate, largely as a result of its preoccupation with identifying and training potential scientists and engineers. This
practice is tyrannical. It must be abandoned forthwith. A realistic alternative is a combined technology and science programme
– perhaps called 'technoscience' education – that would treat science and technology as equals. Such courses may, as well,
be more democratic in the sense that technological problem solving often is more natural to everyday situations that everyone
may find useful, not just future scientists or engineers. A framework for combined technology and science courses is described
and defended here. Originally developed through collaborative action research amongst practising teachers of science, the
approach appears to be feasible, under certain – perhaps ideal – conditions. A number of changes to science and technology
education may be necessary for broader implementation, not the least of which is a general retrenchment in expectations for
pre-determined learning, along with adjustments to teacher education. Nevertheless, the approach is recommended because of
its emphasis on: personalization, inclusion, problematization, explicitness, apprenticeship, authenticity, contextualization
and freedom.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
93.
Australia is unusual among the world's antitrust jurisdictions in not making the pre‐notification of mergers compulsory. However, if the parties are concerned that the Australian Competition and Consumer Commission (ACCC) is likely to object to the merger, there are strong incentives for them to notify the ACCC as the regulator has developed a strong reputation for imposing heavy costs on parties that fail to notify such mergers. The result is a system of quasi‐compulsory notification that creates the strongest incentives for parties to notify the ACCC of those proposals to which it is most likely to object. This study analyses data extracted from the ACCC's merger database and the empirical results are consistent with this characterisation. Mergers reported voluntarily by the parties are found to experience longer delays to completion, and are more likely to be challenged by the ACCC, when compared with a sample of all other mergers assessed by the regulator. The results suggest that non‐compulsory notification allows the parties themselves to pre‐sort the proposed merger vis‐à‐vis its interest to the ACCC. 相似文献
94.
95.
Stephanie Stray 《Quality and Quantity》2009,43(1):161-171
That survey research is error prone is not a new idea and different varieties of non-sampling error have been investigated
in the literature as well as consideration being given in many statistics textbooks to the issue of sampling error. The paper
here considers research upon corporate environmental reporting. It compares information provided by corporate environmental
reports with information that survey respondents claim their organization’s environmental report contains. This enables the
accuracy of the claims to be assessed. Consideration is given to two different industries the Water industry and the Energy
industry. Errors due to inaccurate reporting by survey respondents are shown to be relatively infrequent and respondents appear
just about as likely to claim they report information that they do not, in fact, report as to fail to indicate that they report
information that is, in fact, actually reported. 相似文献
96.
97.
This article specifies what an optimal pollution tax should be when dealing with a vertical Cournot oligopoly. Polluting firms
sell final goods to consumers and outsource their abatement activities to an environment industry. It is assumed that both
markets are imperfectly competitive. Thus, the tax is a single instrument used to regulate three sorts of distortions, one
negative externality and two restrictions in production. Consequently, the optimal tax rate is the result of a trade-off that
depends on the firms’ market power along the vertical structure. A detailed analysis of Cournot-Nash equilibria in both markets
is also performed. In this context, the efficiency of abatement activities plays a key-role. It gives a new understanding
to the necessary conditions for the emergence of an eco-industrial sector.
相似文献
98.
Summary Competition authorities are increasingly measuring the effects of their enforcement actions, seeking a robust justification
for the proliferation of competition policy. We highlight the importance of identifying the right counterfactual against which
to measure effects, and set out the relevant categories of costs and benefits. We then explore how a balance can be struck
between the benefits and inherent limitations of these measurement exercises. Relatively crude analyses of cartel action benefits
can be sufficient to achieve public legitimacy for competition policy. Assessing the effects of merger and conduct inquiries
is often ambiguous, but could be used to improve decision-making processes.
Director and Managing Consultant, respectively, at Oxera, Oxford and London. The valuable comments of Fod Barnes, Kerry Hughes
and an anonymous referee are gratefully acknowledged. The opinions expressed in this article are those of the authors alone. 相似文献
99.
The concept of “inducing growth” is typically considered an adverse consequence of a project on the land use system. In certain instances, however, the desire to induce growth and foster land use change is a focus of land use policy. Such is the example of the Appalachian Highway Development System (AHDS) program initiated by the Appalachian Regional Commission (ARC) during the late 1960s. With the goal of providing highway infrastructure to improve assess to a geographically isolated and historically impoverished region, the ADHS has added nearly 3000 miles of highway to the Appalachian landscape. The degree to which highway investment has contributed to regional growth remains a controversial point and tractable methods to quickly assess landscape change given a project of this magnitude are elusive. In this paper a portion of the AHDS trending through southern Ohio is examined using data acquired from the Landsat series of satellites. Beginning with a pre-highway condition in 1976, a 26 year time horizon, concluding in 2002, was analyzed based on a post-classification change detection methodology. Results of this investigation revealed slight, yet significant, levels of urban expansion within a 10 km corridor along the path of AHDS Corridor D/State Route 32. Beyond this buffer zone the land use system evidenced more stability, suggesting that as distance increased from Corridor D/State Route 32, reduced accessibility also reduced the attractiveness of land for urban uses. Relating these results back to the infrastructure investment policies of the ARC demonstrates that growth did result from the construction of Corridor D and supports previous findings that land development based on highway construction is extremely time-sensitive. 相似文献
100.