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Quantum-Enhanced Blockchain: A Secure and Practical Blockchain Scheme

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Computers, Materials & Continua 2023年第7期76卷 259-277页

作者： Ang Liu Xiu-Bo Chen Gang Xu Zhuo Wang Xuefen Feng Huamin Feng Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Network and Information Management Division Beijing Electronic Science and Technology InstituteBeijing100070China School of Information Science and Technology North China University of TechnologyBeijing100144China School of Artificial Intelligence Beijing University of Posts TelecommunicationsBeijing100876China Mathematics Teaching and Research Center Beijing Fengtai Yihai High SchoolBeijing100070China general office Beijing Electronic Science and Technology InstituteBeijing100070China

The rapid advancement of quantum technology poses significant security risks to blockchain ***,quantum technology can also provide solutions for enhancing blockchain *** this paper,we propose a quantum-enhanced blockchain scheme to achieve a high level of security against quantum computing *** first discuss quantum computing attacks on classic blockchains,including attacks on hash functions,digital signatures,and consensus *** then introduce quantum technologies,such as a quantum hash function(QHF),a quantum digital signature(QDS),and proof of authority(PoA)consensus mechanism,into our scheme to improve the security of the blockchain *** security analysis demonstrates that our scheme offers superior security against quantum and classic ***,we compare our scheme with previous works,showing that our scheme has achieved a perfect balance in terms of practicality,reliability,scalability,and ***,this work contributes to the ongoing research on quantum blockchain in the quantum era.

关键词： Quantum blockchain quantum hash function quantum digital signature

Science and Innovation Diplomacy from a Practitioner's Perspective——A Case-study of “Nordic+” Countries in China

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Innovation and Development Policy 2022年第1期 1-24页

作者： David Bekkers Thomas Hansen Mika Klemettinen Nannan Lundin Consulate general of the Kingdom of the Netherlands in Shanghai Shanghai 201103China Innovation Centre Denmark in Shanghai Shanghai 200336China Business Finland Shanghai office Shanghai 310000China Vinnova-Sweden’s Innovation Agency Stockholm 5610158Sweden

Science and innovation diplomacy is at a crossroad-facing the need for enhanced cooperation to tackle global challenges and in a more complex geopolitical *** on“learning-by-doing”and“learningby-experimenting”as well as focusing on future development needs and opportunities,the science and innovation diplomacy practices of“Nordic+”countries,i.e.,Denmark,Finland,Sweden and the Netherlands,in China are presented in the *** common strategic insights can be summarized as:1)a new policy narrative on“co-opetition”,2)a balanced approach and a long-term and future-oriented perspective on“coopetition”and 3)more agile,targeted and impact-oriented instruments and partnerships for“co-opetition”.Concrete suggestions for the future development include:1)a deepened understanding of how science and innovation are inter-connected with strategic and economic interests of countries and continents,2)publicly funded schemes and instruments for engaging Nordic multinationals and deepening science-industry-policy collaborative efforts,3)systematic methods through combining evidence-based and future-oriented analyses and 4)skill-and capacity development for identifying,preventing and mitigating multifaceted risks in *** such contexts,the implementation of EU’s mission-driven innovation and the twin-transition,*** sustainability transition and digital transition,can open up new opportunities for the future cooperation.

关键词： innovation diplomacy science and innovation policy business-driven innovation

Non-commutative Fock-Darwin system and its magnetism properties

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Chinese Physics B 2009年第9期18卷 3670-3676页

作者：余晓敏李康 Dean office Hangzhou Dianzi University Department of Physics Hangzhou Normal University

The Fock-Darwin system is studied in noncommutative quantum mechanics. We not only obtain its energy eigenvalues and eigenstates in noncommutative phase space, but also give an electron orbit description as well as the general expressions of the magnetization and the susceptibility in a noncommutative situation. Further, we discuss two particular cases of temperature and present some interesting results different from those obtained from usual quantum mechanics such as the susceptibility dependent on a magnetic field at high temperatures, the occurrence of the magnetization in a zero magnetic field and zero temperature limit, and so on.

关键词： Landau diamagnetism space-space non-commutativity momentum momentum non-commutativity

What Does China’s Accession to the Hague Agreement Mean?

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China's Foreign Trade 2022年第2期 59-60页

作者： Hu Gang CCPIT PATENT&TRADEMARK LAW office

On February 5,2022,the Chinese government deposited its instrument of accession to the Geneva text of the Hague Agreement(1999)with the director general of the WIPO,thus becoming the 68th Contracting Party to the 1999 text and the 77th member state of the Hague *** Geneva text of the Hague Agreement(1999)will enter into force in China on May 5,*** preparation for joining the Hague System,China amended the Patent Law on June 1,2021.

关键词： Access Mean text

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3),Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3),Chang-shun WANG~(2,3),Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, Beijing general Research Institute for Nonferrous Metals,Beijing 100088,China 2.Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,Beijing 100072,China 3.Institute of Technology,Beijing North Vehicle Group Corporation,Beijing 100072,China 4.Fengtai Military Representative office,Beijing Military Representative office,PLA,Beijing 100072,China State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China Institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China Fengtai Military Representative office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

The Critical Study On Xu Yuanchong's Theory of Metrical Translation

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海外英语 2012年第7X期 139-143页

作者：麦帼慧 South China Journal of Cardiology Editorial office Guangdong General Hospital

Background:Xu Yuanchong,one of the most eminent translators of Chinese poetry in English rhyme,adhered to the metrical translation which emphasizes transferring the rhyme of the original poem into the translation of target *** it has *** ods:This essay was conducted in qualitative research *** identified and reflected on some negative impacts caused by improper met rical translation and summarized the factors which confine it from the aspect of phonology,semantics and *** tried to figure out the limitations of the metrical translation through examples by analyzing the linguistic features of the language and imagery effect of the translat ed ***:Another translation methods was introduced-free/blank verse translation to solve the deficiencies lied in the metrical translation.

关键词： metrical translation limitation rhyme image meanin

Development of Different Strategies for the Clean-Up of Polychlorinated Biphenyls (PCBs) Congeners Using Pressurized Liquid Extraction

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Journal of Environmental Protection 2013年第1期4卷 99-107页

作者： Amal Al-Rashdan Murad I. H. Helaleh Kuwait Institute for Scientific Research Deputy Director General Office for Research Safat Kuwait

The extracted fish samples (w/w) using pressurized liquid extraction (PLE) were cleaned up by applying different adsorbent materials such as: combination of acidic/ basic silica and alumina, florisil, and silica gel either alone or in combination with another sort of sorbent. Different solvents such as hexane (H), dichloromethane (DCM), with different compositions were used to elute the PCBs target compounds from the spiked fish samples. Overall the mean percentage recoveries for all PCBs congeners using PLE were ranging from 78.6% to 98.7%;from 79.4% to 91.8%;from 65.8% to 104.5% and from 82.4% to 100.9% for cases A, B, C, D and E, respectively. However, the overall mean percentage recoveries for the 13C-PCBs surrogate including: 101, 138, 153, 180 and 209 were ranging from 88.2% to 97.6%;from 79.4% to 90.2%, from 88.3% to 96.4%, from 79.8% to 90.4% and from 83.9% to 95.9%, for cases A, B, C, D and E, respectively. The limits of detection of the proposed method were varied from 0.01 to 0.28 ng/g (w/w) for different PCBs congeners. The proposed method has linear dynamic range from 21.5 ng/g to 109 ng/g. This method was applied to fish samples for the determination of the target PCBs components.

关键词： Polychlorinated Biphenyls (PCBs) Pressurized Liquid Extraction (PLE) Adsorbent Materials Gel Permeation Chromatography (GPC) Negative Chemical Ionization (NCI) Marine Sample

Configuration model of partial repairable spares under batch ordering policy based on inventory state

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Chinese Journal of Aeronautics 2014年第3期27卷 558-567页

作者： Ruan Minzhi Luo Yi Li Hua office of Research & Development Naval University of Engineering Department of Weaponry Engineering Naval University of Engineering

Rational planning of spares configuration project is an effective approach to improve equipment availability as well as reduce life cycle cost （LCC）. With an analysis of various impacts on support system, the spares demand rate forecast model is constructed. According to systemic analysis method, spares support effectiveness evaluation indicators system is built, and then, initial spares configuration and optimization method is researched. To the issue of discarding and con-sumption for incomplete repairable items, its expected backorders function is approximated by Laplace demand distribution. Combining the （s-1, s） and （R, Q） inventory policy, the spares resup-ply model is established under the batch ordering policy based on inventory state, and the optimi-zation analysis flow for spares configuration is proposed. Through application on shipborne equipment spares configuration, the given scenarios are analyzed under two constraint targets：one is the support effectiveness, and the other is the spares cost. Analysis reveals that the result is consistent with practical regulation;therefore, the model＇s correctness, method＇s validity as well as optimization project＇s rationality are proved to a certain extent.

关键词： Batch ordering Inventory state Operations research Partial repairable spares Support effectiveness evaluation

DoCoMo’3G and New Services

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DoCoMo’3G and New Services