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排序方式: 共有273条查询结果,搜索用时 15 毫秒
91.
This study examines the effect of antitrust regulation of patent consolidation on the development of follow-on innovations. Our reconciliation of the various strains of literature hypothesizes that in sectors where cumulative innovation is crucial to firms’ market operations, a firm that consolidates patents for substituting technologies for its already-possessed technologies discourages market competitions and follow-on innovation by competitors. In this case, antitrust regulation of patent consolidation is anticipated to positively affect competitors’ follow-on innovation. We empirically test this hypothesis with the case of the US Department of Justice's regulation of Novell's software patent transfers to four large proprietary software companies (i.e., Microsoft, Oracle, EMC, and Apple) in 2011. Our analyses using US patent, trademark, and copyright data have found evidence corroborating our hypothesis. Our research provides policy and scholarly implications regarding how antitrust law can be a complementary institution to the patent law for promoting innovation. 相似文献
92.
本文从降低供应风险的角度,对2020年前我国原油进口结构的优化路径进行了定量分析。并且为应对伊朗原油出口的减少提出了数量化的政策建议。研究结论显示,由于我国对世界原油的需求将会持续旺盛,在未来几年内,我国需要大量增加从俄罗斯、科威特、阿联酋、卡塔尔、墨西哥及阿尔及利亚等传统产油国的进口,同时减少对沙特阿拉伯、安哥拉、苏丹和伊朗的原油依赖。从未来原油进口的地区分布上看,中东地区依然是我国原油进口的主要来源地,同时也是供应风险最大的地区。为应对伊朗石油禁运,我国应该增加从加拿大、墨西哥、尼日利亚和卡塔尔等国的原油进口来弥补供应缺口,并满足国内快速增长的原油消费需求。 相似文献
93.
Orloff ND Dennis JR Cecchini M Schonbrun E Rocas E Wang Y Novotny D Simmonds RW Moreland J Takeuchi I Booth JC 《Biomicrofluidics》2011,5(4):44107-441079
We present a 91 MHz surface acoustic wave resonator with integrated microfluidics that includes a flow focus, an expansion region, and a binning region in order to manipulate particle trajectories. We demonstrate the ability to change the position of the acoustic nodes by varying the electronic phase of one of the transducers relative to the other in a pseudo-static manner. The measurements were performed at room temperature with 3 μm diameter latex beads dispersed in a water-based solution. We demonstrate the dependence of nodal position on pseudo-static phase and show simultaneous control of 9 bead streams with spatial control of −0.058 μm/deg ± 0.001 μm/deg. As a consequence of changing the position of bead streams perpendicular to their flow direction, we also show that the integrated acoustic-microfluidic device can be used to change the trajectory of a bead stream towards a selected bin with an angular control of 0.008 deg/deg ± 0.000(2) deg/deg. 相似文献
94.
Claudia Conti Chiara Colombo David Dellasega Mauro Matteini Marco Realini Giuseppe Zerbi 《Journal of Cultural Heritage》2011,12(4):372
This study is focused on the evaluation by μRaman mapping of the penetration depth achieved by ammonium oxalate treatment in different plaster specimens, a hot issue in the conservation field. The role of the carbonatic aggregate particles and the influence of the different variables of the treatment on the penetration depth and on the distribution of the newly-formed phase (whewellite) have been ascertained. Based on the results of μRaman mapping, analyses with Field Emission Scanning Electron Microscopy have been carried out in order to observe the whewellite crystals and the carbonatic aggregate particles involved in the reaction with ammonium oxalate. 相似文献
95.
G&#;nther Seeber Bernd Remmele 《美中教育评论》2009,6(2):13-24
A series of studies in several countries tested the economic understanding of people, particularly students. The performance of the subjects is typically conceived as showing "deficits". These alleged deficits seem to correspond with scepticism towards market economy. Better test scores in general correlate with higher appraisal of market society. Could therefore a better understanding influence the attitudes towards phenomena of economic life, like competition, unequal income distribution and other characteristics of market economy? This paper identifies different factors influencing both the levels of economic understanding and the attitudes towards economy. It analyzes results of empirical studies and, as a conclusion, develops an "influence model" reflecting the connection between the form of perception of market-induced phenomena, i.e. economic competence, and the evaluation of these phenomena. The model is the fundament for the design of forthcoming studies. 相似文献
96.
This study investigates the modelling conceptualisation of secondary school students in two situations related to particle dynamics: pendulum’s motion and horizontal motion. We performed in-depth clinical interviews with secondary school students (N?=?10). Participants’ ideas about properties which are not ‘given’ in empirical observations were explored in order to investigate signs of abstractions and idealisations in their reasoning processes. We proposed contributions to modelling in science education based on Mario Bunge’s epistemology and we employed his basic concepts as the axis to analyse our results: (1) abstractions and idealisations, considered as thought processes required to build conceptual counterparts of concrete objects; (2) theoretical models, meaning hypothetico-deductive systems concerning those conceptual objects; and (3) general theoretical frameworks that allow us to derive those theoretical models. We developed our analysis viewing the ideas presented by participants as concepts-in-action and theorems-in-action as regarded by Gérard Vergnaud’s Theory of Conceptual Fields. Results indicated a gradation in the concepts-in-action mobilised in terms of levels of idealisation and showed that participants do not spontaneously recognise the use of a general theory as a possible way to obtain a theoretical model. These results suggest that science education practices must pay better attention to make abstractions and idealisations explicit in scientific concepts formation, as well as to the heuristic role of theories in model construction. 相似文献
97.
Marco Moreira 《Assessment & Evaluation in Higher Education》1985,10(2):159-168
Concept maps are proposed as an alternative tool for evaluation in higher education and examples of concept maps, drawn by college students performing evaluation tasks, are presented in the areas of physics and literature. 相似文献
98.
99.
100.
Luca Caricati Rita Chiesa Dina Guglielmi Marco Giovanni Mariani 《Journal of Higher Education Policy & Management》2016,38(4):490-502
The research undertaken for this article aims to analyse the correspondence between perceived employability and the actual national employment rate among Italian students and graduates undertaking different courses in a large Italian university. Data were collected through a cross-sectional survey of 2087 students in 19 faculties, and compared with the national indicators of employment rate for each faculty. Using faculty as unit of analysis, the results indicated a significant correlation between participants’ perceived employability and national employment rate. This trend was similar for both genders. However, the results showed a difference between bachelor’s and master’s degrees: the correlation between perceived and actual employability was not significant among bachelor’s participants while it remained significant among master’s participants. The results suggest that graduates are only partially aware of their possibility to enter the labour market and this, in turn, highlights that universities have only partially met the goal to increase awareness about the chances of finding a job among students and graduates. 相似文献