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Chinese Optics Letters 2011年第5期9卷 37-40页

作者：于旭东王宇魏国张鹏飞龙兴武 College of Opoelectric Science and Engineering National University of Defense Technology School of Mechanical engineering Nanjing University of Science and Technology College of Opoelectric Science and Engineering National University of Defense Technology

Bias of ring-laser-gyroscope （RLG） changes with temperature in a nonlinear way. This is an important restraining factor for improving the accuracy of RLG. Considering the limitations of least-squares regression and neural network, we propose a new method of temperature compensation of RLG bias building function regression model using least-squares support vector machine （LS-SVM）. Static and dynamic temperature experiments of RLG bias are carried out to validate the effectiveness of the proposed method. Moreover, the traditional least-squares regression method is compared with the LS-SVM-based method. The results show the maximum error of RLG bias drops by almost two orders of magnitude after static temperature compensation, while bias stability of RLG improves by one order of magnitude after dynamic temperature compensation. Thus, the proposed method reduces the influence of temperature variation on the bias of the RLG effectively and improves the accuracy of the gyro scope considerably.

关键词： Error compensation Gyroscopes Neural networks Regression analysis Ring lasers Support vector machines Temperature distribution

In pursuit of reconstructing missing human hands

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National science Review 2023年第5期10卷 13-16页

作者： Xuan Gong Bai-Yang Sun Qi-Ning Wang Cai-Hua Xiong Institute of Medical Equipment science and engineering School of Mechanical Science and Engineering Huazhong University of Science and Technology college of engineering Peking University

Human beings are the most intelligent living beings on Earth.Creating reconstructions of missing human limbs that can be naturally integrated into the human body is a lofty ambition and faces challenges in neuroscience,information science,mechanical and electronic engineering,and many other disciplines.Based on the development history of robotic prosthetic hands over the past 70 years,

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Lithiation-induced controllable vacancy engineering for developing highly active Ni_(3)Se_(2) as a high-rate and large-capacity battery-type cathode in hybrid supercapacitors

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Journal of Energy Chemistry 2023年第3期78卷 37-46,I0002页

作者： Yinna He Ting Liu Jiangnan Song Yiwei Wang Yuxiao Zhang Jie Feng Alan Meng Guicun Li Lei Wang Jian Zhao Zhenjiang Li college of Chemistry and Molecular engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina college of Materials science and engineering College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina

The poor rate capability and low capacity are huge barriers to realize the commercial applications of battery-type transition metal compounds(TMCs) cathode.Herein,numerous Se vacancy defects are introduced into the Ni_(3)Se_(2)lamellas by pre-lithiation technique,which can be acted as a novel class of battery-type cathode for hybrid supercapacitors.Appropriately modulating the contents of the preembedded lithium(Li) ions can induce a controllable vacancy content in the series of as-prepared products,effectively endowing a fast reaction kinetic and high activity for the cathode.Benefiting from the distinct design,the optimized cathode(Li2-Ni_(3)Se_(2)) presents a high specific capacity of 236 mA h g^(-1)at1 A g^(-1),importantly,it can still possess 117 mA h g^(-1)when the current density is increased up to 100A g^(-1),exhibiting relatively high rate capability.It is much superior to other battery-type TMC cathodes reported in previous studies.Moreover,the cathode also shows the excellent cycling stability with 92%capacity retention after 3,000 cycles.In addition,a hybrid supercapacitor(HSC) is assembled with the obtained Li2-Ni_(3)Se_(2)as the cathode and active carbon(AC) as the anode,which delivers a high energy density of 77 W h kg^(-1)at 4 kW kg^(-1)and long-term durability(90% capacitance retention after 10,000 cycles).Therefore,the strategy not only provides an effective way to realize the controllable vacancy content in TMCs for achieving high-perfo rmance cathodes for HSC,but also further promotes their large-scale applications in the energy storage fields.

关键词： Pre-lithiation Selenium vacancies High-rate Battery-type cathode Hybrid supercapacitor

An efficient botnet detection approach based on feature learning and classification

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Journal of Control and Decision 2023年第1期10卷 40-53页

作者： B.Padmavathi B.Muthukumar Department of Computer science and engineering Sathyabama Institute of Science and TechnologyChennaiIndia Computer science and engineering Easwari Engineering CollegeChennaiIndia DMI college of engineering ChennaiIndia

Bot detection is considered a crucial security issue that is extensively analysed in various existingapproaches. Machine Learning is an efficient way of botnet attack detection. Bot detectionis the major issue faced by the existing system. This research concentrates on adopting a graphbasedfeature learning process to reduce feature dimensionality. The incoming samples arecorrectly classified and optimised using an Adaboost classifier with an improved grey wolfoptimiser (g-AGWO). The proposed IGWO optimisation approach is adopted to fulfil the multiconstraintissues related to bot detection and provide better local and global solutions (to satisfyexploration and exploitation). The extensive results show that the proposed g-AGWO model outperformsexisting approaches to reduce feature dimensionality, under-fitting/over-fitting andexecution time. The error rate prediction shows the feasibility of the given model to work over thechallenging environment. This model also works efficiently towards the unseen data to achievebetter generalization.

关键词： Botnet machine learning AdaBoost grey wolf optimisation exploration exploitation

具有O–Fe–Se配位键的半共格异质界面工程提高电池型超级电容器阳极的容量和倍率

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science China Materials 2023年第5期66卷 1767-1778页

作者：宋江楠刘婷何银娜王艺伟张玉晓孟阿兰袁相程王磊李桂村赵健李镇江 college of Electromechanical engineering College of Materials Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China college of Chemistry and Molecular engineering Qingdao University of Science and TechnologyQingdao 266042China School of Materials science and engineering Beihang UniversityBeijing 100191China

低容量和低倍率限制了电池型超级电容阳极材料的大规模应用.本文通过构建一种具有半共格异质界面特性的Fe_(2)O_(3)/FeSe_(2)纳米结构作为先进的阳极材料来解决这一瓶颈.系列表征和第一性原理计算表明,这种特殊的异质界面不仅能自发产... 详细信息

低容量和低倍率限制了电池型超级电容阳极材料的大规模应用.本文通过构建一种具有半共格异质界面特性的Fe_(2)O_(3)/FeSe_(2)纳米结构作为先进的阳极材料来解决这一瓶颈.系列表征和第一性原理计算表明,这种特殊的异质界面不仅能自发产生较强的内建电场,从而提高电子传递速率和OH^(-)离子的吸附能力;还可使得活性物质与OH^(-)之间发生更多的氧化还原反应,并且使该反应体系更容易进行.基于上述优势,所制备出的阳极材料的最大比容量为199.2 mA h g^(-1)(1 A g^(-1)),并且在10 A g^(-1)下仍能保持105.8 mA h g^(-1),同时,经历5000次循环后,其比容量可维持初始值的90.2%.此外,以Fe_(2)O_(3)/FeSe_(2)作为阳极组装的非对称超级电容器在0.8 kW kg^(-1)时的能量密度为52.55 Wh kg^(-1),即使经历15,000次循环,该器件还能维持初始容量的91.2%.我们的工作为设计大容量和高倍率性能的电池型超级电容器阳极材料提供了一种创新性的策略,有望推动过渡金属化合物在储能系统中的大规模应用.

关键词： Fe_(2)O_(3)/FeSe_(2)semicoherent heterojunction O-Fe-Se coordination large capacity rate capability battery-type supercapacitor anode

An Equivalent Substitute Strategy for Constructing 3D Ordered Porous Carbon Foams and Their Electromagnetic Attenuation Mechanism

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Nano-Micro Letters 2022年第10期14卷 15-35页

作者： Meng Zhang Hailong Ling Ting Wang Yingjing Jiang Guanying Song Wen Zhao Laibin Zhao Tingting Cheng Yuxin Xie Yuying Guo Wenxin Zhao Liying Yuan Alan Meng Zhenjiang Li college of Materials science and engineering College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266061People’s Republic of China State Key Laboratory Base of Eco-Chemical engineering College of Chemistry and Molecular EngineeringCollege of Chemical Engineering in Gaomi CampusQingdao University of Science and TechnologyQingdao 266042People’s Republic of China

Three-dimensional(3D)ordered porous carbon is generally believed to be a promising electromagnetic wave(EMW)absorbing material.However,most research works targeted performance improvement of 3D ordered porous carbon,and the specific attenuation mechanism is still ambiguous.Therefore,in this work,a novel ultra-light egg-derived porous carbon foam(EDCF)structure has been successfully constructed by a simple carbonization combined with the silica microsphere template-etching process.Based on an equivalent substitute strategy,the influence of pore volume and specific surface area on the electromagnetic parameters and EMW absorption properties of the EDCF products was confirmed respectively by adjusting the addition content and diameter of silica microspheres.As a primary attenuation mode,the dielectric loss originates from the comprehensive effect of conduction loss and polarization loss in S-band and C band,and the value is dominated by polarization loss in X band and Ku band,which is obviously greater than that of conduction loss.Furthermore,in all samples,the largest effective absorption bandwidth of EDCF-3 is 7.12 GHz under the thickness of 2.13 mm with the filling content of approximately 5 wt%,covering the whole Ku band.Meanwhile,the EDCF-7 sample with optimized pore volume and specific surface area achieves minimum reflection loss(RL_(min))of−58.08 dB at 16.86 GHz while the thickness is 1.27 mm.The outstanding research results not only provide a novel insight into enhancement of EMW absorption properties but also clarify the dominant dissipation mechanism for the porous carbon-based absorber from the perspective of objective experiments.

关键词： Porous carbon foam Electromagnetic wave absorption Adjustable pore structure Polarization loss Attenuation mechanism

Influence of pre-stretching on the tensile strength,fatigue properties and the in-plane anisotropy in Al-Cu-Li alloy AA2099

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Journal of Materials science & Technology 2023年第14期145卷 249-259页

作者： Xianghui Zhu Xusheng Yang Weijiu Huang Weiyi Qiu Xin Wang Fei Guo Li Hu Miao Gong college of Materials science and engineering Kunming University of Science and TechnologyKunming 650093China college of Materials science and engineering Chongqing University of Arts and SciencesChongqing 402160China college of Materials science and engineering Chongqing University of TechnologyChongqing 400044China

The influence of pre-stretching prior to artificial aging on microstructure,tensile properties,and fatigue behavior of AA2099-T8 sheets was investigated.The results showed that increased pre-strain level from 1%to 6%resulted in a more uniform distribution and increasing density of the T_(1)phase.The localized plastic deformation during pre-stretching led to the formation of dense precipitation bands(DPBs)and precipitation free bands(T_(1)-PFBs)in the sheets with the 1%pre-strain.The non-uniform distribution of the T_(1)phase with T_(1)-PFBs and DPBs resulted in a decrement in elongation and a strong in-plane anisotropy of tensile properties.An appropriate level of pre-strain should be executed aiming to improve elongation and reduce the tensile anisotropy by promoting a uniform distribution of the T_(1)phase.In-plane anisotropy of yield strength due to the presence of DPBs and T_(1)-PFBs was quantitatively analyzed by the modified Hall-Petch formula.The results of the calculation for the modified model showed good agreement with the experiment.In addition,resistances of fatigue crack propagation(FCP)in the same orientation were gradually decreased with the increment of pre-strain due to the increment in yield strength and more uniform distribution of the T_(1)phase.For the in-plane anisotropy of FCP resistance,the main reasons were the development of rough fracture surfaces and the transgranular fracture modes in L-T orientation.

关键词： Aluminum-lithium alloys Precipitation Mechanical properties Fatigue crack propagation

Glutamicibacter nicotianae AT6:A new strain for the efficient biodegradation of tilmicosin

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Journal of Environmental sciences 2024年第8期142卷 182-192页

作者： Huijuan Li Hao Zhou Liling Fan Long Meng Yanyun Zhao Lanmei Zhao Bo Wang college of Chemical and Biological engineering Shandong University of Science and TechnologyQingdao 266590China college of Chemistry and Chemical engineering Heze UniversityHeze 274015China college of Safety and Environmental engineering Shandong University of Science and TechnologyQingdao 266590China

The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low cost.Coincidently,we found a new strain,Glutamicibacter nicotianae sp.AT6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal efficiency.The role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM removals.The toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic substances.Based on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.

关键词： Tilmicosin Glutamicibacter nicotianae Biodegradation Degradation pathway Pharmaceutical wastewater

Student Behavior Modeling for an E-Learning System Offering Personalized Learning Experiences

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Computer Systems science & engineering 2022年第3期40卷 1127-1144页

作者： K.Abhirami M.K.Kavitha Devi Department of Computer science and engineering Kings College of EngineeringPudukkottai613303India Department of Computer science and engineering Thiagarajar College of EngineeringMadurai625015India

With the advent of computing and communication technologies,it has become possible for a learner to expand his or her knowledge irrespective of the place and time.Web-based learning promotes active and independent learning.Large scale e-learning platforms revolutionized the concept of studying and it also paved the way for innovative and effective teaching-learning process.This digital learning improves the quality of teaching and also promotes educational equity.However,the challenges in e-learning platforms include dissimilarities in learner’s ability and needs,lack of student motivation towards learning activities and provision for adaptive learning environment.The quality of learning can be enhanced by analyzing the online learner’s behavioral characteristics and their application of intelligent instructional strategy.It is not possible to identify the difficulties faced during the process through evaluation after the completion of e-learning course.It is thus essential for an e-learning system to include component offering adaptive control of learning and maintain user’s interest level.In this research work,a framework is proposed to analyze the behavior of online learners and motivate the students towards the learning process accordingly so as to increase the rate of learner’s objective attainment.Catering to the demands of e-learner,an intelligent model is presented in this study for e-learning system that apply supervised machine learning algorithm.An adaptive e-learning system suits every category of learner,improves the learner’s performance and paves way for offering personalized learning experiences.

关键词： Learner behavior modeling e-learning intelligent learning system machine learning algorithm

Selective immobilization of Pb(Ⅱ)by biogenic whewellite and its mechanism

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Journal of Environmental sciences 2024年第3期137卷 664-676页

作者： Xingxing Wang Kaiyan Ren Kairui Jiao Wenjun Nie Xiaochi An Bin Lian college of Life sciences College of Marine Science and EngineeringNanjing Normal UniversityNanjing 210023China

The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge,but has important application value.Biogenic whewellite(BW)with high selectivity for Pb(Ⅱ)was synthesized by mineral microbial transformation.The selective immobilization properties and mechanism of BW for Pb(Ⅱ)were analyzed by combining mineral characterization technology and batch adsorption research methods.The results indicated that BW can efficiently and selectively immobilize Pb(Ⅱ)in single or composite heavy metal adsorption solutions,and the immobilized Pb(Ⅱ)is difficult to desorb.BW undergoes monolayer adsorption on Pb(Ⅱ),Qmax≈1073.17 mg/g.The immobilization of Pb(Ⅱ)by BW is a physico-chemical adsorption process with spontaneous heat absorption and an accompanying increase in entropy.In addition,the sequestration of Pb(Ⅱ)by BW remains around 756.99 mg/g even at p H=1.The excellent selective immobilization properties of BW for Pb(Ⅱ)are closely related to its smaller Ksp,electrostatic repulsion effect,organic-inorganic composite structure,acid resistance and the formation of Pb(Ⅱ)oxalate.This study provides beneficial information about the recycling of lead in acidic lead-containing wastewater and composite heavy metal contaminated water bodies.

关键词： Aspergillus niger Biogenic whewellite Pb(Ⅱ) Selective adsorption Immobilization mechanism