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Journal of Computer and Communications 2024年第7期12卷 59-77页

作者： Fazal Raheman quantsoft systems ltd. Tallinn Estonia

With one billion users using 380 exchanges, the security of blockchains and cryptocurrencies remains a major concern as billions are lost to hackers every year. Cryptocurrency hacks negatively impact cryptocurrency markets introducing volatility. Each major scam/hack incident results in a significant price dip for most cryptocurrencies, decelerating the growth of the blockchain economy. Existing blockchain vulnerabilities are further amplified by the impending existential threat from quantum computers. While there’s no reprieve yet from the scam/hack prone blockchain economy, quantum resilience is being aggressively pursued by post quantum cryptography (PQC) researchers, despite 80 of 82 candidate PQCs failing. As PQC has no role in combating inherent vulnerabilities, securing over 1000 existing blockchains against scammers/hackers remains a top priority for this industry. This research proposes a novel Quantum-safe Ledger Technology (QLT) framework that not only secures DLTs/cryptocurrencies and exchanges from current vulnerabilities but protects them from the impending Q-day threats from future quantum computers. As blockchain-agnostic technology, the QLT framework can be easily adapted to secure any blockchain or crypto exchange.

关键词： Cybersecurity Quantum Computers Post Quantum Cryptography Q-Day Zero Trust

An Image Fingerprint and Attention Mechanism Based Load Estimation Algorithm for Electric Power System

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 577-591页

作者： Qing Zhu Linlin Gu Huijie Lin Electricity Technology Branch Nari Technology Co.Ltd.Nanjing211106China NARI-TECH Nanjing Control systems Co. Ltd.Nanjing211106China

With the rapid development of electric power systems,load estimation plays an important role in system operation and ***,load estimation techniques contain traditional,time series,regression analysis-based,and machine learning-based *** the machine learning-based method can lead to better performance,in this paper,a deep learning-based load estimation algorithm using image fingerprint and attention mechanism is ***,an image fingerprint construction is proposed for training *** the data preprocessing,the training data matrix is constructed by the cyclic shift and cubic spline ***,the linear mapping and the gray-color transformation method are proposed to form the color image ***,a convolutional neural network(CNN)combined with an attentionmechanism is proposed for training performance *** last,an experiment is carried out to evaluate the estimation *** with the support vector machine method,CNN method and long short-term memory method,the proposed algorithm has the best load estimation performance.

关键词： Load estimation deep learning attention mechanism image fingerprint construction

Enhanced wear prediction of tunnel boring machine disc cutters for accurate remaining useful life estimation using a hybrid model

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 642-662页

作者： Xinghai ZHOU Yakun ZHANG Guofang GONG Huayong YANG Qiaosong CHEN Yuxi CHEN Zhixue SU The State Key Laboratory of Fluid Power&Mechatronic systems Zhejiang UniversityHangzhou 310027China Guangzhou Rail Transit Construction Engineering Consulting Co. Ltd.Guangzhou 510000China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450016China

In tunnel construction with tunnel boring machines(TBMs),accurate prediction of the remaining useful life(RUL)of disc cutters is critical for timely maintenance and replacement to avoid delays and cost *** paper introduces a novel hybrid model,integrating fundamental and data-driven approaches,to enhance wear prediction of TBM disc cutters and enable accurate RUL *** fundamental model is improved by incorporating composite wear mechanisms and load estimation techniques,showcasing superior prediction accuracy compared to single-mechanism ***,the hybrid model innovatively incorporates a data-driven supplementary residual term into the improved fundamental model,leading to a high-performance wear prediction *** actual field data from a highway tunnel project in Shenzhen,the performance of the hybrid model is rigorously tested and compared with pure fundamental and data-driven *** hybrid model outperforms the other models,achieving the highest accuracy in predicting TBM disc cutter wear(mean absolute error(MAE)=0.53,root mean square error(RMSE)=0.64).Furthermore,this study thoroughly analyzes the hybrid model’s generalization capability,revealing significant impacts of geological conditions on prediction *** model’s generalization capability is also improved by expanding and updating the data *** RUL estimation results provided by the hybrid model are straightforward and effective,making it a valuable tool by which construction staff can monitor TBM disc cutters.

关键词： tunnel boring machine disc cutter wear prediction remaining useful life field data hybrid model

Tungsten separation behavior on preparation of high-purity cerium by combined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech Co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials Co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a combined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum content of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this combined ***,this paper provides a new method for the removal of high density and low evaporation coefficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech Co. Ltd.Langfang065201China GRIREM Advanced Materials Co. Ltd.Beijing100088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most common mining *** high contents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A comprehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary concentrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum concentration in Chongzuo samples decreases continuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the concentration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the consumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

Embracing connected intelligence with the YuanOS architecture:one OS kit for all

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Frontiers of Computer Science 2024年第1期18卷 1-3页

作者： Haibo CHEN Ning JIA Jie YIN Institute of Parallel and Distributed systems School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China OS Kernel Lab Huawei Technologies Co.Ltd.Beijing 100085China

Operating system abstracts hardware and creates application execution environment,and thus is the key pillar for IT *** its first invention in 1956,operating system has been evolved over three main stages:Mainframe,PC&Internet,Mobile Internet[1].Now,the entire society is firmly stepping towards the connected intelligence era[2],how should operating system be evolved to embrace this new era?

关键词： hardware execution connected

Current status and development of CMOS SiPM for scintillator-based radiation detectors toward all-digital sensors[Invited]

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Chinese Optics Letters 2024年第2期22卷 17-27页

作者： Nicola D'Ascenzo 胡文韬劳慧华越轩张博房磊奚道明郑睿邱奥 Emanuele Antonecchia 凌怡清刘雨晴李琰俞航肖鹏谢庆国 Wuhan National Laboratory for Optoelectronics Wuhan 430074China Biomedical Engineering Department Huazhong University of Science and TechnologyWuhan 430074China RAYQUANT Technology Co. Ltd.Ezhou 436044China RAYSOLUTION Healthcare Co. Ltd.Hefei 230000China RAYMEASURE Technology Co. Ltd.Suzhou 215000China RAYCAN Technology Co. Ltd.Suzhou 215000China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China

Modern scintillator-based radiation detectors require silicon photomultipliers(Si PMs)with photon detection efficiency higher than 40%at 420 nm,possibly extended to the vacuum ultraviolet(VUV)region,single-photon time resolution(SPTR)<100 ps,and dark count rate(DCR)<150 kcps/mm^(2).To enable single-photon time stamping,digital electronics and sensitive microcells need to be integrated in the same CMOS substrate,with a readout frame rate higher than 5 MHz for arrays extending over a total area up to 4 mm×4 *** is challenging due to the increasing doping concentrations at low CMOS scales,deep-level carrier generation in shallow trench isolation fabrication,and power consumption,among *** advances at 350 and 110 nm CMOS nodes are benchmarked against available Si PMs obtained in CMOS and commercial customized *** concept of digital multithreshold Si PMs with a single microcell readout is finally reported,proposing a possible direction toward fully digital scintillator-based radiation detectors.

关键词： silicon photomultiplier complementary metal-oxide semiconductor digital SiPM

Atomistic mechanism of high ionic conductivity in lithium ytterbium-based halide solid electrolytes:A first-principles study

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Journal of Rare Earths 2024年第1期42卷 155-162,I0006页

作者： Limin Wang Wei Xiao Lu Sun Rong Yang Jinqiu Yu Ligen Wang State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co.Ltd.Beijing100088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute Co. Ltd.Beijing101407China Rare Earth Functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an071700China

As the next generation of commercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the ***-so lid-state batteries have attracted the attention of countless researchers around the world because of their high safety and high energy *** recent times,halide solid-state electrolytes have become a research hotspot within solid-state electrolytes because of their potentially superior *** this paper,in the framework of DFT,we investigated the atomic mechanisms of improving the ionic conductivity and stability of Li_(3)YbCl_(6).Our calculations show that both trigonal and orthorhombic Li_(3)YbCl_(6) exhibit wide electrochemical windows and metastable properties(100 meV/atom>Ehull>0 meV/atom).However,the orthorhombic Li_(3)YbCl_(6) can be stabilized at high temperatures by taking the vibrational entropy into account,which is supported by the experimental ***,it is expected that because of the Yb/Li synergistic interactions that,due to their strong mutual coulomb repulsion,influence the Li^(+)transport behavior,the orthorhombic Li_(3)YbCl_(6) might have superior ionic conductivities with appropriate Li+migration paths determined by the Yb^(3+) ***,higher ionic conductivities can be obtained by regulating the random distribution of Li^(+) *** Li^(+)-deficiency can also largely increase the ionic conductivity by invoking *** study helps gain a deeper understanding of the laws that govern ionic conductivities and stabilities and provides a certain theoretical reference for the experimental development and design of halide solid-state electrolytes.

关键词： Halide solid-state electrolytes Phase stability Ionic conductivity First-principles calculations Rare earths

Laminar Flame Instability of n-Hexane,n-Octane,and n-Decane in Spherical Expanding Flames

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Journal of Thermal Science 2024年第3期33卷 1189-1199页

作者： YIN Geyuan HU Erjiang LI Xiaotian LV Xin HUANG Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China United Automotive Electronic systems Co. LtdShanghai201206China Chongqing Changan Automobile Co. Ltd.Chongqing401120China

This paper focuses on the laminar flame instability of three high molecular weight n-alkanes,namely n-hexane,n-octane,and *** experiment was carried out in a constant volume combustion bomb to get the flame *** critical radius under different conditions was extracted using the image processing *** with the existing critical Peclet number theory,the dominant factors of flame instability under current conditions for three n-alkanes can be figured ***,the average cell size(equivalent cell radius,R_(cell))was extracted to provide quantitative analysis of the flame cellular structure,based on the method developed in this *** theoretical R_(cell)were also calculated and compared with the experimental results to validate the proposed method.

关键词： cellular instability equivalent cell radius critical Peclet number spherical flame

Experimental aspects of ^(14)N overtone RESPDOR solid-state NMR spectroscopy under MAS beyond 60 kHz

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Magnetic Resonance Letters 2024年第1期4卷 40-49页

作者： Yutaro Ogaeri Yusuke Nishiyama JEOL ltd. AkishimaTokyo196-8558Japan

Nitrogen-14(^(14)N)overtone(OT)spectroscopy under fast magic angle spinning(MAS)conditions(>60 kHz)has emerged as a powerful technique for observing correlations and distances between ^(14)N and ^(1)H,owing to the absence of the first-order quadrupolar broad*** addition,^(14)N^(OT) allows selective manipulation of ^(14)N nuclei for each *** extensive theoretical and experimental studies,the spin dynamics of ^(14)N^(OT) remains under *** this study,we conducted experimental investigations to assess the spin dynamics of ^(14)N^(OT) using the rotational-echo saturation-pulse double-resonance(RESPDOR)sequence,which monitors population transfer induced by a^(14)N^(OT) *** ^(14)N^(OT) spin dynamics is well represented by a model of a two-energy-level *** spin-1/2,the maximum excitation efficiency of ^(14)N^(OT) coherences of powdered solids,denoted by p,depends on the radiofrequency field(rf-field)strength due to orientation dependence of effective nutation fields even when pulse lengths are *** is also found that the p factor,contributing to the ^(14)N^(OT) spin dynamics,is nearly independent of the B0 ***,the filtering efficiency of RESPDOR experiments exhibits negligible dependence on B0 when the ^(14)N^(OT) pulse length is *** study also identifies the optimal experimental conditions for ^(14)N^(OT)/^(1)H RESPDOR correlation experiments.

关键词： ^(14)N Overtone RESPDOR ^(14)N/^(1)H correlation Solid-state NMR Fast MAS