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Geometric Design-based Dimensional synthesis of a Novel Metamorphic Multi-fingered Hand with Maximal Workspace

Chinese Journal of Mechanical Engineering 2021年第3期34卷 211-225页

作者： Wei An Jun Wei Xiaoyu Lu jian s.dai Yanzeng Li MOE Key Laboratory for Mechanism Theory and Equipment Design International Centre for Advanced Mechanisms and RoboticsTianjin UniversityTianjinChina Advanced Kinematics and Reconfigurable Robotics Lab School of Natural and Mathematical SciencesKing’s College LondonLondonUK Rutgers The State University of New JerseyNew BrunswickNew JerseyUSA

Current research on robotic dexterous hands mainly focuses on designing new finger and palm structures,as well as developing smarter control *** the dimensional synthesis of dexterous hands with traditional rigid palms has been carried out,research on the dimensional synthesis of dexterous hands with metamorphic palms remains *** study investigated the dimensional synthesis of a palm of a novel metamorphic multi-fingered hand,and explored the geometric design for maximizing the precision manipulation *** indexes were used to value the workspace of the metamorphic hand,and the best proportions between the five links of the palm to obtain the optimal workspace of the metamorphic hand were *** on the fixed total length of the palm member,four nondimensional design parameters that determine the size of the palm were introduced;through the discretization method,the influence of the four design parameters on the workspace of the metamorphic hand with full-actuated fingers and under-actuated fingers was *** on the analysis of the metamorphic multi-fingered hand,the symmetrical structure of the palm was designed,resulting in the largest workspace of the multi-fingered hand,and proved that the metamorphic palm has a massive upgrade for the workspace of underactuated *** research contributed to the dimensional synthesis of metamorphic dexterous hands,with practical significance for the design and optimization of novel metamorphic hands.

关键词： Metamorphic hands Dimensional synthesis Maximal workspace Discretization

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A Finite and Instantaneous screw Based Approach for Topology Design and Kinematic Analysis of 5-Axis Parallel Kinematic Machines

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 66-75页

作者： Tao sun shuo-Fei Yang Tian Huang jian s.dai Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University school of Engineering The University of Warwick Centre for Robotics Research School of Natural Sciences and Mathematics King’s College London University of London

Unifying the models for topology design and kinematic analysis has long been a desire for the research of parallel kinematic machines(PKMs). This requires that analytical description, formulation and operation for both finite and instantaneous motions are performed by the same mathematical tool. Based upon finite and instantaneous screw theory, a unified and systematic approach for topology design and kinematic analysis of PKMs is proposed in this paper. Using the derivative mapping between finite and instantaneous screws built in the authors’ previous work, the finite and instantaneous motions of PKMs are analytically described by the simple and non?redundant screws in quasi?vector and vector forms. And topological and parametric models of PKMs are algebraically formulated and related. These related topological and parametric models are ready to do type synthesis and kinematic analysis of PKMs under the unified framework of screw theory. In order to show the validity of the proposed approach, a kind of two?translational and three?rotational(2T3R)5?axis PKMs is taken as example. Numerous new structures of the 2T3R PKMs are synthe?sized as the results of topology design, and their Jacobian matrix is obtained easily for parameter optimization and performance evaluation. some of the synthesized PKMs have outstanding capabilities in terms of large workspaces and flexible orientations, and have great potential for industrial applications of machining and manufacture. Among them, METROM PKM is a typical example which has attracted a lot of attention from global companies and already been developed as commercial products. The approach is a general and unified approach that can be used in the innovative design of different kinds of PKMs.

关键词： Innovative design Parallel kinematic machines screw theory Finite screw Instantaneous screw

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New nonlinear stiffness actuator with predefined torque‒deflection profile

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Frontiers of Mechanical Engineering 2023年第1期18卷 217-233页

作者： Wenjie JU Hexi GONG Keke QI Rongjie KANG jian sdai Zhibin sONG school of Mechanical Engineering Tianjin UniversityTianjin 300350China College of Engineering Department of Mechanical and Energy EngineeringSouthern University of Science and TechnologyShenzhen 518055China King’s College London University of LondonWC2R 2LS LondonUK

A nonlinear stiffness actuator(NsA)could achieve high torque/force resolution in low stiffness range and high bandwidth in high stiffness range,both of which are beneficial for physical interaction between a robot and the ***,most of NsAs are complex and hardly used for *** this paper,oriented to engineering applications,a new simple NsA was proposed,mainly including leaf springs and especially designed cams,which could perform a predefined relationship between torque and *** new NsA has a compact structure,and it is lightweight,both of which are also beneficial for its practical *** analytical methodology that maps the predefined relationship between torque and deflection to the profile of the cam was *** optimal parameters of the structure were given by analyzing the weight of the NsA and the mechanic characteristic of the leaf *** sliding friction force is inevitable because no rollers were used in the cam-based mechanism,the sliding displacement between the cam and the leaf spring is very small,and consumption of sliding friction force is very *** of different torque‒deflection profiles were carried out to verify the accuracy and applicability of performing predefined torque‒deflection *** kinds of prototype experiments,including verification experiment of the predefined torque‒deflection profile,torque tracking experiment,and position tracking experiment under different loads,were *** results prove the accuracy of performing the predefined torque‒deflection profile,the tracking performance,and the interactive performance of the new NsA.

关键词： compliant actuator nonlinear stiffness actuator nonlinear spring predefined torque−deflection profile

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strong evidence for latitudinal diversity gradient in mosses across the world

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Plant Diversity 2024年第4期46卷 537-541页

作者： Hong Qian Zun dai jian Wang Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA Bryology Laboratory School of Life SciencesEast China Normal UniversityShanghai 200241China shanghai Institute of Eco-Chongming(sIEC) 3663 Northern Zhongshan RoadShanghai 200062China

species richness generally decreases with increasing latitude,a biodiversity gradient that has long been considered as one of the few laws in *** latitudinal diversity gradient has been observed in many major groups of *** plants,the latitudinal diversity gradient has been observed in vascular plants,angiosperms,ferns,and ***,a conspicuous latitudinal diversity gradient in mosses at a global or continental scale has not been observed until ***,we analyze a comprehensive data set including moss species in each band of 20° in latitude *** results show that moss species richness decreases strongly with increasing latitude,regardless of whether the globe is considered as a whole or different longitudinal segments(e.g.,Old World versus New World) are considered *** result holds when variation in area size among latitudinal bands is taken into ***'s correlation coefficient between latitude and species richness is-0.99 for both the Northern and southern *** bryophytes are an extant lineage of early land plants and because mosses not only include most of extant species of bryophytes but also are important constituents of most terrestrial ecosystems,understanding geographic patterns of mosses is particularly important The finding of our study fills a critical knowledge gap.

关键词： Bryophyte Latitudinal diversity gradient Moss species density species diversity

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Ultralow-phase-noise and broadband frequency-hopping coupled optoelectronic oscillator under quiet point operation

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Photonics Research 2024年第8期12卷 1785-1793页

作者： HUI LIU MINGYANG GUO TIAN ZHANG jian dai KUN XU state Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China school of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Advancements in microwave photonics have yielded novel approaches for generating high-purity microwave *** these,optoelectronic oscillators(OEOs)and coupled optoelectronic oscillators(COEOs)have demonstrated the capability to generate frequency-independent microwaves with exceptionally low phase ***,the tunability of the oscillators is rather limited due to the necessity for narrowband electronic bandpass filters,presenting challenges in achieving both wide and rapid tuning ***,we present a COEO featuring ultralow phase noise,flexible tuning capability,and high *** is achieved through a quiet point(QP)-operated harmonic mode-locked fiber laser,which effectively mitigates optical amplifier noise and supermode competition,thus significantly diminishing the necessity for ultra-narrow electronic *** to the liberated tuning ability,we present an oscillator that can be tuned from 2 GHz to 18 GHz,with phase noise as low as-140 d Bc/Hz at 10 k Hz under the QP *** then illustrate the practical application of the proposed oscillator in generating frequency-hopping signals with consistent spurious modes less than-85 d Bc,absolute phase noise below-135 d Bc/Hz at 10 k Hz,hopping resolution of 1.25 MHz,and fractional frequency stability below 6.1×10^(-12)at 1 s averaging time when locked to a *** presented COEO structure emerges as a compelling solution for agile and low-noise microwave sources in advanced wireless communication and radar systems.

关键词： optoelectronic tuning amplifier

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Quantitative characterizations of anisotropic dynamic properties in organic-rich shale with different kerogen content

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Petroleum science 2024年第2期21卷 855-865页

作者： jian-Yong Xie Yan-Ping Fang Xing-Hua Wu jian'er Zhao Jun-Cheng dai Jun-Xing Cao Ji-Xin Deng state Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Key Lab of Earth Exploration&Information Techniques of Ministry of Education Geophysical InstituteChengdu University of TechnologyChengdu610059SichuanChina PetroChina southwest Oil&Gasfield Company Chengdu610017SichuanChina

Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and *** controlled experiments with a single variable is challenging for natural shales due to their high variations in components,diagenesis conditions,or pore *** employed the hot-pressing technique to construct 11 well-controlled artificial shale with varying *** artificial shale samples were successive machined into prismatic shape for ultrasonic measurements along different *** revealed bedding perpendicular P-wave velocities are more sensitive to the increasing KC than bedding paralleling velocities due to the preferential alignments of *** elastic stiffnesses except C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Apparent dynamic mechanical parameters(v and E)were found to have linear correlation with the true ones from complete anisotropic equations independent of KC,which hold value towards the interpretation of well logs consistently across formations,Anisotropic mechanical parameters(ΔE and brittlenessΔB)tend to decrease with the reducing KC,withΔB showing great sensitivity to KC *** the range of low KC(s) ratio demonstrated a linearly negative correlation with KC,and the V_(P)/V_(s) ratio magnitude of less than 1.75may serve as a significant characterization for highly organic-rich(>10%)shale,compilation of data from natural organic rich-shales globally verified the similar systematic relationships that can be empirically used to predict the fraction of KC in shales.

关键词： Elastic properties Organic shale Anisotropy Kerogen content Physical modeling

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stable Cycling of All-solid-state Lithium Batteries Enabled by Cyano-Molecular Diamond Improved Polymer Electrolytes

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Nano-Micro Letters 2024年第10期16卷 561-575页

作者： Yang dai Mengbing Zhuang Yi-Xiao Deng Yuan Liao jian Gu Tinglu song Hao Yan Jin-Cheng Zheng Department of Chemical Engineering Shanghai UniversityShangda Road 99Shanghai 200444People's Republic of China Department of Physics Xiamen UniversityXiamen 361005People's Republic of China Experimental Center of Advanced Materials school of Materials science and Engineering Beijing Institute of TechnologyBeijing 100081People's Republic of China Department of Physics and Department of New Energy science and Engineering Xiamen University Malaysia43900 SepangMalaysia

The interfacial instability of the poly(ethylene oxide)(PEO)-based electrolytes impedes the long-term cycling and further application of all-solid-state lithium metal *** this work,we have shown an effective additive 1-adaman-tanecarbonitrile,which con-tributes to the excellent per-formance of the poly(ethylene oxide)-based *** to the strong interaction of the 1-Adamantanecarboni-trile to the polymer matrix and anions,the coordination of the Li^(+)-EO is weakened,and the binding effect of anions is strengthened,thereby improving the Li^(+)conductivity and the electrochemical *** diamond building block on the surface of the lithium anode can sup-press the growth of lithium ***,the 1-Adamantanecarbonitrile also regulates the formation of LiF in the solid electrolyte interface and cathode electrolyte interface,which contributes to the interfacial stability(especially at high voltages)and protects the electrodes,enabling all-solid-state batteries to cycle at high voltages for long periods of ***,the Li/Li symmetric cell undergoes long-term lithium plating/stripping for more than 2000 h.1-Adamantanecarbonitrile-poly(ethylene oxide)-based LFP/Li and 4.3 V Ni_(0.8)Mn_(0.1)Co_(0.1)O_(2)/Li all-solid-state batteries achieved stable cycles for 1000 times,with capacity retention rates reaching 85%and 80%,respectively.

关键词： 1-Adamantanecarbonitrile(ADCN) Poly(ethylene oxide) All-solid-state batteries Interfacial stability High voltage

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Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

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Defence Technology（防务技术） 2024年第9期39卷 23-41页

作者： Ziqi Zhao Tong Li Donglin sheng jian Chen Amin Yan Yan Chen Haiying Wang Xiaowei Chen Lanhong dai state Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China school of Future Technology University of Chinese Academy of SciencesBeijing 100049 China school of Engineering science University of Chinese Academy of SciencesBeijing 100049China state Key Laboratory of Explosion science and Technology Beijing Institute of TechnologyBeijing 100081China

shaped charge liner(sCL)has been extensively applied in oil recovery and defense *** superior penetration capability through optimizing sCL structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse,high-speed jet stretching,and *** study introduces an innovative optimization strategy for sCL structures that employs jet penetration efficiency as the primary objective *** strategy combines experimentally validated finite element method with machine learning(FEM-ML).We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine *** index effectively evaluates the jet penetration ***,a multi-model fusion based on a machine learning optimization method,called XGBOOsT-MFO,is put forward to optimize sCL structure over a large input *** strategy's feasibility is demonstrated through the optimization of copper sCL implemented via the FEM-ML ***,this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper ***,the strategy can provide helpful guidance for the engineering design of sCL.

关键词： Jet penetration efficiency shaped charge liner FEM-ML XGBOOsT MFO High-entropy alloy

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Feasibility of low-intensity ultrasound treatment with hydroxylamine to accelerate the initiation of partial nitrification and allow operation under intermittent aeration

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Journal of Environmental sciences 2024年第5期139卷 446-459页

作者： jianxiong jian Xiaojian Liao Zhihua Mo shoupeng Li Lei Li shaojin Chen Zhenhua Huang Junhao Chen Wencan dai shuiyu sun Guangzhou Key Laboratory Environmental Catalysis and Pollution Control Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlSchool of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangdong Province solid Waste Recycling and Heavy Metal Pollution Control Engineering Technology Research Center Guangdong Polytechnic of Environmental Protection EngineeringFoshan 528216China Analysis and Test Center Guangdong University of TechnologyGuangzhou 510006China

Partial nitrification is a key aspect of efficient nitrogen removal,although practically it suf-fers from long start-up cycles and unstable long-term operational *** address these drawbacks,this study investigated the effect of low intensity ultrasound treatment combined with hydroxylamine(NH2OH)on the performance of partial *** showthat compared with the control group,low-intensity ultrasound treatment(0.10W/mL,15 min)combined with NH2OH(5 mg/L)reduced the time required for partial nitrification initiation by 6 days,increasing the nitrite accumulation rate(NAR)and ammonia nitro-gen removal rate(NRR)by 20.4% and 6.7%,respectively,achieving 96.48% ***-tic analysis showed that NH2OH enhanced ammonia oxidation,inhibited nitrite-oxidizing bacteria(NOB)activity and shortened the time required for partial nitrification ***,ultrasonication combined with NH2OH dosing stimulated EPs(extracellular polymeric substances)secretion,increased carbonyl,hydroxyl and amine functional group abundances and enhanced mass *** addition,16s rRNA gene sequencing results showed that ultrasonication-sensitive Nitrospira disappeared from the ultrasound+NH_(2)OH system,while Nitrosomonas gradually became the dominant ***,the results of this study provide valuable insight into the enhancement of partial nitrification start-up during the process of wastewater nitrogen removal.

关键词： Partial nitrification Low-intensity ultrasound Hydroxylamine Ammonia oxidizing bacteria Nitrite oxidizing bacteria

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Development and validation of a prediction model for early screening of people at high risk for colorectal cancer

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World Journal of Gastroenterology 2024年第5期30卷 450-461页

作者： Ling-Li Xu Yi Lin Li-Yuan Han Yue Wang jian-Jiong Li Xiao-Yu dai Department of General surgery Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina Center for Health Economics Faculty of Humanities and Social SciencesUniversity of NottinghamNingbo 315100Zhejiang ProvinceChina Department of Global Health Ningbo Institute of Life and Health IndustryUniversity of Chinese Academy of SciencesNingbo 315000Zhejiang ProvinceChina school of Public Health Medical College of Soochow UniversitySuzhou 215123Jiangsu ProvinceChina

BACKGROUND Colorectal cancer(CRC)is a serious threat *** early screening is suggested to be the most effective method to prevent and control CRC,the current situation of early screening for CRC is still not *** China,the incidence of CRC in the Yangtze River Delta region is increasing dramatically,but few studies have been ***,it is necessary to develop a simple and efficient early screening model for *** To develop and validate an early-screening nomogram model to identify individuals at high risk of *** Data of 64448 participants obtained from Ningbo Hospital,China between 2014 and 2017 were retrospectively *** cohort comprised 64448 individuals,of which,530 were excluded due to missing or incorrect *** 63918,7607(11.9%)individuals were considered to be high risk for CRC,and 56311(88.1%)were *** participants were randomly allocated to a training set(44743)or validation set(19175).The discriminatory ability,predictive accuracy,and clinical utility of the model were evaluated by constructing and analyzing receiver operating characteristic(ROC)curves and calibration curves and by decision curve ***,the model was validated internally using a bootstrap resampling *** seven variables,including demographic,lifestyle,and family history information,were *** logistic regression analysis revealed that age[odds ratio(OR):1.03,95%confidence interval(CI):1.02-1.03,Pss index(BMI)(OR:1.07,95%CI:1.06-1.08,Pst circumference(WC)(OR:1.03,95%CI:1.02-1.03 Pstyle(OR:0.45,95%CI:0.42-0.48,Pstory(OR:4.28,95%CI:4.04-4.54,Pst significant predictors of high-risk *** lifestyle was a protective factor,whereas family history was the most significant risk *** area under the curve was 0.734(95%CI:0.723-0.745)for the final validation set ROC curve and 0.735(95%CI:0.728-0.742)for the training s

关键词： Colorectal cancer Early screening model High-risk population Nomogram model Questionnaire survey Dietary habit Living habit

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