BC-BLPM:A Multi-Level Security Access Control Model Based on Blockchain Technology

Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchain is widely used in the field of access control with its decentralization,traceability and non-defective modification.Combining the blockchain technology and the Bell-LaPadula model,we propose a new access control model,named BCBLPM,for MLS environment.The“multi-chain”blockchain architecture is used for dividing resources into isolated access domains,providing a fine-grained data protection mechanism.The access control policies are implemented by smart contracts deployed in each access domain,so that the side chains of different access domains storage access records from outside and maintain the integrity of the records.Finally,we implement the BC-BLPM prototype system using the Hyperledger Fabric.The experimental and analytical results show that the model can adapt well to the needs of multi-level security environment,and it has the feasibility of application in actual scenarios.     

基于密码和区块链技术的数据交易平台设计

尽管数据流动和交易是大势所趋,但当前数据交易的热情并不高涨。文章分析了数据的特殊性和当前数据交易的模式,数据交易平台有能力留存交易数据成为交易双方的潜在威胁,成为数据交易的障碍。基于对密码技术、区块链技术和开源开放机制的研究,设计一种去中心化的新型交易平台,从技术上保证平台没有机会查看、复制和留存交易数据,实现交易数据只在交易双方中安全流转。     

日本Yahoo ! BB宽带业务模式案例分析

Yahoo！BB的宽带运营思路 Yahoo！BB是由日本BB科技公司(BBTC)和Yahoo！日本公司联合推出的宽带业务。该业务的推出是受韩国ADSL市场巨大突破的启发,准备在日本本土大面积地移植和发展。该业务主要     

Product Innovation in High-tech SMEs： A Case Study of Weili Electronics Co., Ltd

Scholars argue that product innovation is a critical strategy for the high-tech small and medium enterprises (SMEs). Despite of its potential attractive, the empirical findings on the impact of product innovation strategy on SMEs performance appear inconclusive. In fact, Capon et al. found that empirical results of prior researches have been mixed, with over two-thirds of the studies finding a positive relationship between product innovation strategy and firm performance, and the rest findin…     

基于区块链技术的移动医疗系统设计与实现

随着生活水平的提高,获取信息的渠道增多以及健康观念的改变,人们越来越注重自己和亲朋好友的身体健康.近年来,健康养生的话题不断被提起,且养生话题逐渐变得年轻化.湖南省长沙市开福区人民政府在2021年中国家庭健康大会上提出把家庭健康促进作为最大的民生工程,提升全区居民健康素养.庞大的健康需求会产生巨大的医疗信息数据,一套安...     

Product Innovation in High-tech SMEs: A Case Study of Weili Electronics Co., Ltd

Product innovation is an important strategy for high-tech firms, especially for small and medium enterprises. This paper proposes that the technological strategies for SMEs are dynamic and during different phase, there is different innovation strategy which leads to various market performances. In particular, through the case study of Weili Electronics Co., Ltd, we find that organizational learning abilities play a fundamental role in strategic decision. In addition, the frameworks for the determinants of technological strategies in three stages are established to illustrate the evolutionary processes of product innovation in Weili Electronics Co., Ltd.     

基于散射点模型的ISAR干扰技术研究

针对弹载干扰装备干扰功率较小,难以对逆合成孔径雷达(Inverse Synthetic Aperture Radar, ISAR)形成有效的干扰,文中分析了ISAR成像原理,针对ISAR成像过程中包络对齐这一环节,提出了一种基于散射点模型的压制性干扰信号,该信号可破坏ISAR成像过程中目标回波的包络对齐,进而形成多种干扰效果。该信号在进入ISAR后可获得较大的脉冲压缩增益,能以较小的干扰功率达到较好的干扰效果。理论分析与仿真实验验证了该种干扰信号对ISAR干扰的有效性。     

Profitability of RE-Technology Regarding the Economic Environment: A Case Study of Swiss SMEs

Considering the important changes in the Swiss energy sector, especially in renewable energy (RE) technologies, new revenue possibilities for small and medium sized enterprises (SMEs) emerge. However, the adaption of RE-technologies for Swiss enterprises relies on tangible financial returns, based on complex calculations. This article analyses business opportunities (BOs) of eight Swiss SMEs considering the net present value of RE-investments in an uncertain economic environment. We identify two profitable BOs for Swiss SMEs and three which are not profitable. Further, the article demonstrates that the profitability of such investments remains mostly positive even under economic uncertainties. Surprisingly the profitability does not change significantly if the SME receives a subsidy or not. The support instrument of the Swiss Government has not a ponderous impact on the decision to invest in RE-technologies or not. Therefore, the article emphasizes the importance of including SME in the Swiss attempt to decentralize the energy market.     

Factors Influencing Strategic Use of Information Technology and Its Impact on Business Performance of SMEs

In this paper, we study the relationship between factors influencing the strategic use of IT and business performance by conducting a survey of small and medium‐size enterprises (SMEs). From the results of our survey we came to several conclusions which are presented here. First, IT investment has a significant impact on the strategic use of IT, and the strategic use of IT has a significant impact on business performance. Second, SME investment in IT and strategic use of IT are influenced by both the intensity of competition in the market environment and partnership with other organizations. Third, the support from the management group in SMEs is a core factor for IT investment and strategic use of IT. Finally, for SMEs to use IT strategically and successfully, it is necessary to combine members' participation with a flexible organizational structure and culture.     

Blockchain Security Technology Based on the Asynchronous Transmission Mode of IoT Technology in Smart Cities

Wireless Personal Communications - With the rapid development of information technology, issues such as network security and privacy protection have attracted more and more attention. The...     

基于DOM的数据转换技术及案例研究

着重介绍用DOM解析XML文件,并在浏览器中呈现其解析结果.之后具体描述一个电子商务典型案例,即用DOM解析XML商品信息文件并对其修改,然后用XML样式表语言模板XSLT(XML Stylesheet Language Template)将其呈现在浏览器中,同时给出关键代码.该文可以使DOM程序员能够对使用DOM处理XML文件的方法有一个直观的认识,并能够深入了解DOM各接口的使用方法,从而为更深一步学习DOM在其他领域的应用打下基础.     

Endogenous Innovation in Chinese IC Firms： A Case Study Based on the Technology Strategy Evolution of NSBIC

It is a common sense that enterprise is the principal of endogenous innovation, but why many firms do not innovate actively？ What kind of difficulty will enterprises suffer in endogenous innovation？ What can the government do for the endogenous innovation？ These questions are very crucial to realize endogenous innovation. This paper tries to answer the questions mentioned above from the perspective of technology evolution. The industrial environment of emerging technology is emphasized for analyzing the endogenous innovation in Chinese enterprises. The process of endogenous innovation in NanShanBridge Co. Ltd （NSBIC）, which is an IC design firm, is analyzed as a case. From the case study, we can answer the questions above in certain extent, give some suggestions to the enterprises as a later-comer, and present some advice to government.     

基于混合隐私的区块链高效模型协同训练共享方案

针对海量数据下,基于区块链的联邦学习数据共享平台面临的效率低下和隐私泄露问题,该文提出基于混合隐私的区块链高效模型协同训练共享方案。在该方案中,首先根据欧氏距离设计了一种基于相似度的训练成员选择算法来选择训练成员,组成联邦社区,即通过选取少量的高匹配训练节点来提高训练的效率和效果。然后,结合阈值同态加密和差分隐私,设计一种基于混合隐私技术的模型协同训练共享方案来保证训练和共享过程中的隐私性。实验结果和系统实现表明,所提方案可以在保证训练结果准确率的情况下,实现高效训练和隐私保护下的数据共享。     

雷达伺服系统中非线性控制技术研究

在分析智能积分器和非线性比例积分微分的控制特点基础上,针对雷达伺服系统工作需求,研究一种非线性控制器设计方法,探讨了控制器的参数整定过程.这种非线性控制器利用了非线性变化特性,解决伺服系统跟踪的快速性和平稳性问题.仿真和实践表明,这种非线性控制提高了雷达伺服系统的跟踪性能,减小雷达伺服系统跟踪过程的加速度滞后误差(动态滞后).非线性控制器结构简单,运算方便,调整参数少,易于整定,有利于工程实践.     

A Case Study in Embedded Systems Design: An Engine Control Unit

A number of techniques and software toolsfor embedded system design have been recently proposed. However,the current practice in the designer community is heavily basedon manual techniques and on past experience rather than on arigorous approach to design. To advance the state of the artit is important to address a number of relevant design problemsand solve them to demonstrate the power of the new approaches.We chose an industrial example in automotive electronics to validateour design methodology: an existing commercially available EngineControl Unit. We discuss in detail the specification, the implementationphilosophy, and the architectural trade-off analysis. We analyzethe results obtained with our approach and compare them withthe existing design underlining the advantages offered by a systematicapproach to embedded system design in terms of performance anddesign time.     

A Study on the Challenges and Solutions of Blockchain Interoperability

With the development of blockchain technology, a variety of mutually independent blockchains such as Bitcoin and Ethereum, as well as private and consortium chains, coexist in large numbers. As a linker of the blockchain network, blockchain interoperability will link more blockchain ecosystems, realize the interconnection of the blockchain and enhance the scalability of the blockchain. This paper summarizes typical blockchain interoperability projects.Firstly, it proposes a blockchain interopera...     

基于全局背景模型和辅助模型的说话人确认系统的研究

大多数说话人确认系统都设置一个背景模型用于描述假冒者的特性。文中提出一种新的说话人确认背景模型,对所有说话人采用同一全局背景模型（UBM）,并为每个说话人建立一个竞争者模型（cohort model）和一个疏远者模型（c-cohort model）。在全局背景模型不能做出准确判断的情况下,启用竞争者模型或疏远者模型再次进行判决。该模型充分利用了相近者模型和疏远者模型的特性。实验表明新的背景模型使系统性能有明显的提高。     

RFID''s Impacts on Business Value: A Case Study of Supply Chain in the Discrete Manufacturing Industry

Radio frequency identification (RFID) shall be a revolutionary technological innovation in recent years. Various solutions employing RFID technology have proved their functionality already in such industries as pharmaceuticals, express parcel carrying, and automotive manufacturing, and the increased efficiency and effectiveness has provided a good payback for the investments. But, up to now, fewer researches concentrate on applying RFID to heavy-machinery manufacturing enterprises, which are a typical kind of enterprises in discrete manufacturing industry. The main objective of this case study is to extend our understanding of the potential for RFID to delivery of the heavy-machinery manufacturing enterprise, which involves one specific supply chain. A trial to automate the verification activities of delivery is designed and performed. Results show that the stops currently designed into the processes can be eliminated by employing RFID technology and that RFID should be a revolutionary technology as it redesigns the existing processes, eliminate some current inefficiency, improve the accuracy of delivering the products, increases information sharing between supply chain members.     

A Study of the Simulation Model in WCDMA Systems

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