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T-PBFT: An EigenTrust-Based Practical Byzantine Fault Tolerance Consensus Algorithm

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China Communications 2019年第12期16卷 111-123页

作者： Sheng Gao Tianyu Yu Jianming zhu Wei Cai School of Information Central University of Finance of EconomicsBeijing 100081China Grain Information Processing and Control Key Laboratory of Ministry of Education Henan University of TechnologyZhengzhou 450001China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.

关键词： blockchain consensus protocol Byzantine fault tolerance trust model

Influence factors on the seismic behavior and deformation modes of gravity retaining walls

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Journal of Mountain Science 2019年第1期16卷 168-178页

作者： zhu Hong-wei YAO Ling-kan LI Jing School of Environment and Resource Southwest University of Science and Technology MOE Key Laboratory of High-speed Railway Engineering Southwest Jiaotong University School of Civil Engineering Southwest Jiaotong University

This study investigated the influence factors on the seismic response and deformation modes of retaining walls using large-scale model shaking table tests. Experimental results showed that the distribution of peak seismic earth pressures along the height of a wall was a single peak value curve. The seismic earth pressures on a gravel soil retaining wall were larger than the pressures on the weathered granite and quartz retaining walls. Also, the peak seismic earth pressure increased with increases in the peak ground acceleration and the wall height. The measured seismic active earth pressures on a rock foundation retaining wall were larger than the calculated values, and the action position of resultant seismic pressure was higher than 0.33 H. In the soil foundation retaining wall, the measured seismic earth pressures were much smaller than the calculated values, while the action position was slightly higher than 0.33 H. The soil foundation retaining wall suffered base sliding and overturning under earthquake conditions, while overturning was the main failure mode for the rock foundation retaining walls.

关键词： Gravity retaining wall Earthquake action Seismic behavior Deformation mode Shaking table test

Attribution of the Langshan Tectonic Belt: Evidence from zircon U-Pb ages and Hf isotope compositions

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Geoscience Frontiers 2019年第2期10卷 539-551页

作者： Chuang Bao Yuelong Chen Xiangkun zhu Junxiang Zhao Key Laboratory of Crustal Dynamics Institute of Crustal DynamicsCEA School of Earth Sciences and Resources China University of Geosciences Laboratory of Isotope Geology MLRInstitute of GeologyCAGS

This study describes a previously unidentified Neoproterozoic mafic dyke emplaced in the northern flank of the Langshan Tectonic Belt. This dyke intruded into the micaquartz schist of the Zhaertaishan Group, and yielded an age of 908 ± 8 Ma. The youngest U-Pb ages of micaquartz schist from the Zhaertaishan Group in the Langshan area were 1118 ± 33 Ma,1187 ± 3 Ma and 1189 ± 39 Ma,suggesting that the depositional age of the protolith of the schist was between 908 ± 8 Ma and 1118 ± 33 Ma. In addition, 436 U-Pb age data and 155 Lu-Hf isotopic data from six samples in the Langshan Tectonic Belt and one Permian greywacke from the Wuhai area show distinct differences between the northern and southern flanks of the Main Langshan area. The U-Pb ages of the northern flank are primarily Meso-Neoproterozoic; similar ages have not been identified in the southern flank to ***, two-stage Hf model ages of the northern flank feature three age peaks at ～900 Ma,～1700 Ma and ～2600 Ma; this differs from Hf model ages of the southern flank, which feature one strong age peak at ～2700 Ma. These results suggest that the northern and southern flanks of the Main Langshan area have different geochronologic characteristics and should be divided further. Based on the U-Pb ages and Hf model ages, the northern and southern flanks of the Main Langshan area are named the North and South Langshan Tectonic Belts. Comparison of the U-Pb age and two-stage Hf model age distributions from the North Langshan Tectonic Belt, South Langshan Tectonic Belt, Alxa Block and the North China Craton(NCC) reveal that the North Langshan Tectonic Belt is similar to the Alxa Block and that the South Langshan Tectonic Belt is similar to the NCC. In addition, the zircon U-Pb age of 860 ±7 Ma commonly observed in the Alxa Block was detected in the Permian greywacke from the Wuhai area of the NCC, which suggests that the amalgamation of the North and South Langshan Tectonic belts(i.e.,the amalgamation of the Alxa

关键词： Langshan Tectonic Belt Attribution Alxa Block North China Craton U-Pb Hf isotopic composition

Principle, Method of Object-Relation Hypermedia Data Model and Its Application in the Multimedia Spatial Data Management

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Journal of Systems Engineering and Electronics 2000年第1期11卷 53-60页

作者： Wang, Jianhua Guo, Jingjun zhu, Guorui Wu, Hehai Tsinghua Univ Beijing China

In this paper, a new multimedia data model, namely object-relation hypermedia data model (O-RHDM) which is an advanced and effective multimedia data model is proposed and designed based on the extension and integration of non first normal form (NF2) multimedia data model. Its principle, mathematical description, algebra operation, organization method and store model are also discussed. And its specific application example, in the multimedia spatial data management is given combining with the Hainan multimedia touring information system.

关键词： Data structures Information management Mathematical models

Biosynthetic pathway of terpenoid indole alkaloids in Catharanthus roseus

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Frontiers of Medicine 2014年第3期8卷 285-293页

作者： Xiaoxuan zhu Xinyi Zeng Chao Sun Shilin Chen Institute of Medicinal Plant Development China Academy of Medical Sciences & Peking Union Medical College Beijing 100193 China Institute of Chinese Materia Medica China Academy of-Chinese Medical Sciences Beijing 100700 China

Catharanthus roseus is one of the most extensively investigated medicinal plants, which can produce more than 130 alkaloids, including the powerful antitumor drugs vinblastine and vincristine. Here we review the recent advances in the biosynthetic pathway of terpenoid indole alkaloids （TIAs） in C. roseus, and the identification and characterization of the corresponding enzymes involved in this pathway. Strictosidine is the central intermediate in the biosynthesis of different TIAs, which is formed by the condensation of secologanin and tryptamine. Secologanin is derived from terpenoid （isoprenoid） biosynthetic pathway, while tryptamine is derived from indole biosynthetic pathway. Then various specific end products are produced by different routes during downstream process. Although many genes and corresponding enzymes have been characterized in this pathway, our knowledge on the whole TIA biosynthetic pathway still remains largely unknown up to date. Full elucidation of TIA biosynthetic pathway is an important prerequisite to understand the regulation of the TIA biosynthesis in the medicinal plant and to produce valuable TIAs by synthetic biological technology.

关键词： Catharanthus roseus terpenoidindole alkaloids biosynthetic pathway vinblastine vincristine

Temperature-Triggered Hardware Trojan Based Algebraic Fault Analysis of SKINNY-64-64 Lightweight Block Cipher

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Computers, Materials & Continua 2023年第6期75卷 5521-5537页

作者： Lei zhu Jinyue Gong Liang Dong Cong Zhang Communication and Electronics Engineering Institute Qiqihar UniversityQiqihar161006China

SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a variety of ways,but it is still difficult to achieve a precisely located fault attacks at a low cost,whereas a Hardware Trojan(HT)can realize ***,as a physical quantity incidental to the operation of a cryptographic device,is easily *** this paper,a temperature-triggered HT(THT)is designed,which,when activated,causes a specific bit of the intermediate state of the SKINNY-64-64 to be ***,in this paper,a THT-based algebraic fault analysis(THT-AFA)method is *** demonstrate the effectiveness of the method,experiments on algebraic fault analysis(AFA)and THT-AFA have been carried out on *** the THT-AFA for SKINNY-64-64,it is only required to activate the THT 3 times to obtain the master key with a 100%success rate,and the average time for the attack is 64.57 ***,when performing AFA on this cipher,we provide a relation-ship between the number of different faults and the residual entropy of the *** comparison,our proposed THT-AFA method has better performance in terms of attack *** the best of our knowledge,this is the first HT attack on SKINNY-64-64.

关键词： SKINNY-64-64 lightweight block cipher algebraic fault analysis Hardware Trojan residual entropy

Late Triassic–Cenozoic Thermochronology in the Southern Sanjiang Tethys, SW China, New Insights from Zircon Fission Track Analysis

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Journal of Earth Science 2019年第5期30卷 996-1004页

作者： Li Yang Wanming Yuan Xiaoyong zhu Zhen Shi Science Research Institute China University of Geosciences

The Sanjiang Tethys orogenic belt is located in the southeast side of the Qinghai-Tibet Plateau. It has undergone the opening and closing movements in different periods of Tethys oceans, complex accretive orogeny and strong mineralization from Paleozoic to Mesozoic. Using zircon fission track(ZFT) thermochronology, this study reveals the Sanjiang Tethys has experienced multi-stage tectonic activities during the Late Triassic–Cenozoic. The 15 ZFT ages with their decomposition components obtained from Sanjiang Tethysian region range from 212 to 19 Ma, which not only shows 6 age groups of 212, 179–172, 156–133, 121–96, 84–70 and 50–19 Ma, but also constrains the age limit of the tectonothermal events. These age groups recorded the Paleo-Tethys main and branches ocean opening/closure time. The age-elevation plot indicates the Sanjiang region had differential uplifting and exhumation and fast uplifting times of ca. 133, 116 and 80 Ma, coinciding with the age groups mentioned above. These results show new geochronological evidences and viewpoints.

关键词： tectonic events zircon fission track analysis tethys evolution Sanjiang region Qinghai-Tibet Plateau thermochronology

Influence of axial distance on pre-whirl regulation by the inlet guide vanes for a centrifugal pump

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Science China(Technological Sciences) 2012年第4期55卷 1037-1043页

作者： TAN Lei CAO ShuLiang WANG YuMing zhu BaoShan State Key Laboratory ofTribology Tsinghua UniversityBeijing 100084China State Key Laboratory of Hydrosc-ience and Engineering Tsinghua UniversityBeijing 100084China

The valuation of the hydraulic performance of a centrifugal pump with pre-whirl regulation of the inlet guide vanes was studied experimentally by varying the pre-whirl angle from -60° to 60° with distances between the inlet guide vanes and the impeller inlet of 280 mm, 380 mm and 460 mm. The efficiency-flow curves and the characteristic curves were obtained for the pump for various operation conditions. The experiment results demonstrated that the pre-whirl regulation widened the high efficiency zone and improved the hydraulic performance for off-design conditions with the proper pre-whirl angle. The axial distance between the inlet guide vanes and the impeller inlet influenced the pre-whirl regulation effect of the inlet guide vanes with the best pre-whirl regulation effect obtained for an axial distance of 380 mm. These results showed that an appropriate axial distance between the inlet guide vanes and the impeller inlet can improve the fluid flow at the impeller entrance with pre-whirl regulation for centrifugal pumps.

关键词： centrifugal pump inlet guide vanes axial distance pre-whirl regulation

The occurrence of gold in pyrite from the Liulincha gold ore belt,western Hunan Province,China

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Chinese Journal Of Geochemistry 2013年第4期32卷 392-397页

作者： LI Zengsheng zhu Xiaoqing LU Huanzhang HAN Tao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences University of Chinese Academy of Sciences University of Quebec at Chicoutimi

In this study,an electron microprobe analyzer(EMPA) was used to map the spatial distribution and the occurrence of invisible gold in pyrite from the Liulincha gold ore *** data show that gold mainly occurs as submicroscopic-microscopic *** the contrast of the major guide elements of pyrite from the Liulincha gold ore belt and those from four hydrothermal-type gold deposits in the Jiaodong region,we can see the pyrites were formed in two stages:the pyrite from wall rock is mainly sedimentogenic,with simple structure;and the pyrite from ore body experienced early sedimentary process to late hydrothermal activity,the pyrite is regular in crystal form and exhibits fractured structure.

关键词：黄铁矿金矿带湖南省电子探针分析西部中国断裂结构空间分布