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Secure multiparty computation has become a central research focus in the international cryptographic community and in the future likely will represent an integral part of computing science. Protocols for Yao’s millionaires’ problem provide the building blocks for many secure multiparty computation protocols, which makes their efficiency critical. Unfortunately, all known protocols for Yao’s millionaires’ problem employ public key cryptography and thus are inefficient. This article constructs a new efficient solution to Yao’s millionaires’ problem based on symmetric cryptography. We first develop an efficient protocol for set-inclusion problems, which has independent interest for secure multiparty computations. The privacy-preserving property of the solution is demonstrated by a well-accepted simulation paradigm. To compare the security levels of different solutions, we propose a new security paradigm that quantitatively captures the security levels of different solutions and can determine which secure multiparty computation solution is preferable. This article thus provides an important supplement to the simulation paradigm. Together with the simulation paradigm, it offers a complete security evaluation benchmark for multiparty computations. 相似文献
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Optimal distributed power allocation for a new spectrum sharing paradigm in cognitive radio networks
The problem of power allocation in cognitive radio networks plays an important role to improve the efficiency of spectrum utilization. However, most of previous works focus on the power allocation for secondary users in spectrum sharing overlay or spectrum sharing underlay, which needs to frequently handoff between the idle spectrum bands or considers the interference constraints in all spectrum bands respectively. In order to reduce the handoff and fully utilize the spectrum resource, we propose a new spectrum sharing paradigm which not only can just need to adjust the transmit power in spectrum bands instead of frequently handoff between idle spectrum bands, but can fully utilize the spectrum resource as we only consider the interference power constraints in active spectrum bands rather than in all spectrum bands. Then based on this new spectrum sharing paradigm and the constraint conditions, we study the distributed power allocation for secondary users and formulate the optimization problem as a non-cooperative game problem, after that the variational inequality approach is used to solve this game problem and a Nash equilibria solution is got, finally simulation results are illustrated to demonstrate the performance of the proposed scheme. 相似文献
35.
工程管理专业教育范式的转型策略 总被引:2,自引:0,他引:2
大工程观的提出使得工程管理人才的素质必须符合“理念、人、物、我”四方面的圆融整合要求。受传统科学范式的影响,目前工程管理专业培养的人才已不能适应新形势的需要,教育范式的转换已成为工程管理专业教育的当务之急。在对工程教育的科学范式与工程范式进行辨析的基础上,深入剖析了工程范式的基本特征,强调新形势下工程管理专业教育应采用工程范式,其转型策略为:从教育价值观的重新定位出发,通过课程体系的改革,再辅以校园文化的重建,从而实现工程管理专业教育范式由科学范式向工程范式的转换。 相似文献
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This study expands the scope of research on knowledge search and innovation search by investigating the effect of boundary-spanning search behavior on breakthrough innovations of new ventures. Based on an environmental coalignment perspective, we argue that boundary-spanning search is a key activity for new ventures so that they can deal with different market forces to enhance their breakthrough innovations. Most of the hypotheses proposed are supported by the results of a survey of 227 ventures in the high-technology zone of Shenzhen. We found that boundary-spanning search is not only associated positively with breakthrough innovations of new ventures but also plays a significant role in influencing the effect of market forces on both types of innovations. This paper offers insight into the way in which new ventures can achieve both market innovations and technological innovations through different types of boundary-spanning search. Furthermore, this study argues that boundary-spanning search is an important tool that enables new ventures to create more innovative performance under competitive environments. 相似文献
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The rough sets analysis focusing on the ownership, locational and internalization (OLI) advantages of Chinese construction multinational corporations (MNCs) in the international market under Dunning's Eclectic Paradigm was adopted to overcome the sample size constraint in MNC research that seeks to examine the causality patterns of the factors identified. The rough sets methodology provides a solution that conventional statistical methods do not offer to ascertain how these factors are determined and their influence in the OLI analysis of the performance of Chinese construction MNCs. The rough sets approach to handling imperfect data with uncertainty and vagueness was adopted to describe dependencies between attributes, evaluate the significance of attributes and deal with inconsistencies. Based on a questionnaire survey of 31 Chinese construction MNCs, findings from the rough sets analysis suggest, among other things, that: (1) a firm is likely to perform well in terms of its ownership advantages when it has a significant advantage on its reputation and its accessibility to resources when compared with local contractors; (2) a firm may be expected to achieve better results in terms of its locational advantages if the large number of competitors from China in the host countries becomes its most important consideration; and (3) a firm that conscientiously avoids or reduces information search and business negotiation costs would tend to perform well in terms of its internalization advantages. 相似文献
38.
化学产品工程作为化学工程学科的一个新方向或化学工程学科的新范式已提出很多年,但学术界对其学科内涵理解不一。本文对化学产品工程的学科内涵进行了分析和探讨,认为其核心是通过过程和设备对产品的纳微结构和复杂大分子结构进行调控;化学产品工程仍隶属过程工程,是面向高附加值产品、实现产品结构可控、定向、高效制备的过程工程。通过与传统的以满足市场需求和提高生产效率为目标的过程开发和放大的化学工程研究类比,提出了化学产品工程的主要研究内容,并讨论了其研究的方法论问题,以推动相关的基础研究工作。 相似文献
39.
Alvin G. Stern 《International Journal of Hydrogen Energy》2018,43(9):4244-4255
We analyze the feasibility of a novel, hydrogen fuel cell electric generator to provide power with zero noise and emissions for myriad ground based applications. The hydrogen fuel cell electric generator utilizes a novel, scalable apparatus that safely generates hydrogen (H2) on demand according to a novel method, using a controlled chemical reaction between water (H2O) and sodium (Na) metal that yields hydrogen gas of sufficient purity for direct use in fuel cells without risk of contaminating sensitive catalysts. The sodium hydroxide (NaOH) byproduct of the hydrogen producing reaction, is collected within the apparatus for later reprocessing by electrolysis, to recover the Na reactant. The detailed analysis shows that the novel, hydrogen fuel cell electric generator will be capable of meeting the clean power requirements for residential and commercial buildings including single family homes and light commercial establishments under a wide range of geographic and climatic conditions. 相似文献
40.
新中国早期产品品牌的命名和设计,在政治内容、审美趣味与商业企图之间获得了平衡。构建了易于被大众接受,群众喜闻乐见,紧随时代潮流的命名和设计范式。其中,以烟标最为典型,散发出鲜明的视觉特色和独有魅力,给人们留下诸多的回忆。为新中国立国建国、经济建设、航天国防、友好和平和文化生活等方面信息的传播和价值观的塑造,作出了不可忽视的贡献,也为现代产品品牌的命名和设计提供了早期的范式参考。 相似文献