检索结果-南通市图书馆

Feature extraction of induction motor stator fault based on particle swarm optimization and wavelet packet

在线全文

学校读者我要写书评

暂无评论

Journal of Coal Science & Engineering(China) 2012年第4期18卷 432-437页

作者： WANG Pan-pan SHI Li-ping HU Yong-jun miao chang-xin School of Information and Electrical Engineering China University of Mining&TechnologyXuzhou 221008China

To effectively extract the interturn short circuit fault features of induction motor from stator current signal, a novel feature extraction method based on the bare-bones particle swarm optimization （BBPSO） algorithm and wavelet packet was proposed. First, according to the maximum inner product between the current signal and the cosine basis functions, this method could precisely estimate the waveform parameters of the fundamental component using the powerful global search capability of the BBPSO, which can eliminate the fundamental component and not affect other harmonic components. Then, the harmonic components of residual current signal were decomposed to a series of frequency bands by wavelet packet to extract the interturn circuit fault features of the induction motor. Finally, the results of simulation and laboratory tests demonstrated the effectiveness of the proposed method.

关键词： induction machine stator winding intertum short circuit bare-bones particle swarm optimization feature extraction wavelet packet fault diagnosis

Pyridine-regulated Sb@InSbS_(3)ultrafine nanoplates as high-capacity and long-cycle anodes for sodium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2080-2092页

作者： Jia-Ying Ren Xiang-Lin Yu chang-miao Chen xin-Yu Hu Ting Yang Ming Zhang College of Materials Science and Engineering and College of Science Central South University of Forestry and TechnologyChangsha 410004China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China

Sb-based materials exhibit considerable potential for sodium-ion storage owing to their high theoretica ***,the bulk properties of Sb-based materials always result in poor cycling and rate *** overcome these issues,pyridine-regulated Sb@InSbS_(3)ultrafine nanoplates loaded on reduced graphene oxides(Sb@InSbS_(3)@rGO)were designed and *** the synthesis process,pyridine was initially adopted to coordinate with In^(3+),and uniformly dispersed In_(2)S_(3)ultrafine nanoplates on reduced graphene oxide were generated after ***,partial In^(3+)was exchanged with Sb^(3+),and Sb@InSbS_(3)@rGO was obtained by using the subsequent annealing *** unique structure of Sb@InSbS_(3)@rGO effectively shortened the transfer path of sodium ions and electrons and provided a high *** the anode in sodium-ion batteries,the Sb@InSbS_(3)@rGO electrode demonstrated a significantly higher reversible capacity better stability(445 m Ah·g^(-1)at 0.1 A·g^(-1)after 200 cycles and 212 mAh·g^(-1)at 2 A·g^(-1)after 1200 cycles),and superior rate(210 mAh·g^(-1)at 6.4 A·g^(-1))than the electrode without pyridine(355 mAh·g-1at 0.1 A·g-1after 55 cycles and 109 mAh·g^(-1)at 2 A·g^(-1)after 770 cycles)Furthermore,full cells were assembled by using the Sb@InSbS_(3)@rGO as anode and Na_(3)V_(2)(PO_(4))_(3)as cathode which demonstrated good cycling and rate performances and exhibited promising application *** results indicate that adjusting the microstructure of electrode materials through coordination balance is A·good strategy for obtaining high-capacity,high-rate,and longcycle sodium storage performances.

关键词： Sodium-ion battery Sb-based anode material Pyridine coordination Reduced size nanostructure Half/full cell

Dual modification of LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2) cathode materials by K^(+) doping and Li_(3)PO_(4) coating for lithium ions batteries

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第7期43卷 3007-3018页

作者： Wei Xiao Jia-Le Wang Zhi-Cheng Yi Cheng-Jin Liu chang miao Yu xin Shu-Qing Nie College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou 434023China

Li_(3)PO_(4)@Li_(0.99)K_(0.01)Ni_(0.83)Co_(0.11)Mn_(O.06)O_(2)(NCM-KP) cathode powders are synthesized via K^(+)doping in calcination processes and H_3PO_4 coating in sol-gel processes.K^(+) precisely enters into the lattice to widen the(003) plane to 0.4746 nm with a lower cationic disordered degree of 1.87%.Moreover,the surface residual lithium salts are treated by H_3PO_4 to generate a uniform Li_(3)PO_(4) coating layer of approximately 11.41 nm,which completely covers on the surface of secondary spherical particles to improve the interfacial *** 25℃,the NCM-KP electrode delivers a discharge specific capacity of 148.9 mAh·g^(-1) with a remarkable capacity retention ratio of 84.1% after 200 cycles at 1.0C and retains a high reversible specific capacity of 154.4 mAh·g^(-1) at *** at 1.0C and 60℃,it can maintain a reversible discharge specific capacity of 114.6 mAh·g^(-1) with 0.21% of capacity decay per cycle after 200 cycles,which is significantly lower than 0.40% for the pristine NCM ***,the charge transfer resistance of 238.89 Ω for the NCM-KP electrode is significantly lower than 947.41 Ω for the pristine NCM one by restricting the interfacial side ***,combining K+doping and Li_(3)PO_(4) coating is an effective strategy to enable the significant improvement of the electrochemical property of high-nickel cathode materials,which may be mainly attributed to the widened diffusion pathway and the formed Li_(3)PO_(4) protective layer,thus promoting Li~+diffusion rate and preventing the erosion of HF.

关键词： High-nickel cathode material Residual lithium K^(+)doping Li_(3)PO_(4)coating Lithium ions battery

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai Jian miao Jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Effects of Aromatherapy on Physical and Mental Health of Cancer Patients Undergoing Radiotherapy and/or Chemotherapy: A Meta-Analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2024年第5期30卷 449-457页

作者： XIE Shuang-ran MA Liang XU xin-yu ZHOU Shu XIE Hui-miao XIE chang-sheng The First Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053China Department of Medical Oncology Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHangzhou 310007China Department of Dermatology the Third Xiangya HospitalCentral South UniversityChangsha 410013China Department of Famous Chinese Medicine Clinic the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310005China Department of Medical Oncology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006China

Backgroup:Currently,aromatherapy is being increasingly utilized in clinical practice,particularly in managing the side effects associated with radiotherapy and ***,it remains to be established whether aromatherapy can effectively alleviate these ***:To investigate the effects of aromatherapy on the physical and mental health of patients with cancer undergoing radiotherapy and ***:Seven databases were researched from inception until September 29,2023,including PubMed,Scopus,and Web of Science,Chinese National Knowledge Infrastructure,Wanfang database,China Biology Medicine disc and VIP Chinese Medical Journal *** Manager version 5.3 was utilized for data *** Cochrane Risk of Bias tool RoB2 was employed to evaluate the quality of the literature included in the *** quality rating was assessed using the Grading of Recommendations Assessment,Development,and Evaluation(GRADE) approach through the GRADEpro GDT online ***:Nineteen studies involving 1,541 patients were *** can alleviate nausea [relative risk(RR)=0.64,95% confidence interval(CI):0.53 to 0.78,P<0.05,I^(2)=46%;standardized mean difference(SMD)=-0.86,95% CI:-1.21 to-0.51,P<0.05,I^(2)=64%] and vomiting(RR=0.54,95% CI:0.42 to 0.69,P<0.05,I^(2)=35%;SMD=-1.28,95% CI:-1.52 to-1.03,P<0.05,I^(2)=92%),improve sleep disorders [mean difference(MD)=-3.39,95% CI:-3.95 to-2.84,P<0.05,I^(2)=0%],relieve pain(SMD=-1.58,95% CI:-1.96 to-1.21,P<0.05,I^(2)=0%),mitigate fatigue(SMD=-1.28,95% CI:-2.44 to-0.11,P<0.05,I^(2)=93%) and enhance quality of life(SMD=0.50,95% CI:0.22 to 0.79,P<0.05,I^(2)=0%) in cancer patients after radiotherapy and chemotherapy,but it may not have a significant effect on *** risk of bias was high in the included studies using the Cochrane Risk of Bias tool RoB2,and no studies were considered to be of high grade according to the GRADE ***:Aromatherapy is an efficacious,safe a

关键词： aromatherapy cancer chemoradiotherapy physical psychological

Origin and evolution of false brinelling and fretting corrosion under rolling conditions

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第4期12卷 618-631页

作者： xin JIA Lu HUANG miao SUN Wenbin LI National Institute of Metrology Beijing 100029China Yantai Tiancheng Machinery Co. Ltd.Yantai 264006China

Rolling bearings working in oscillating applications often suffer from false brinelling and fretting corrosion that limit their service *** present,the study of oscillation-induced failures is primarily dominated by a large number of sliding and bench ***,most of the previous work are not able to fully describe the two closely related but different failure *** this study,the origin and evolution of the two failures are thoroughly investigated under strictly controlled oscillating rolling *** results show that failure evolves from false brinelling to fretting corrosion under dry friction conditions regardless of the oscillation *** process is accompanied by a large area peeling and serious oxidation,and the oxygen content increases from 2.50 wt%to 21.22 wt%.Oxidation is a crucial factor in the evolution of false brinelling into fretting ***,the distribution of microwear and oxygen content depend on the oscillation *** lubrication conditions,the friction coefficient(COF)is smaller in the initial stage and led to local slip or transient instability of rolling ***,the size of the wear marks and COF increased and appeared to be larger than those under a dry friction ***,grease can separate the contact surfaces,only surface deformation owing to false brinelling and slight damage at the roughness level *** evolution of false brinelling and fretting corrosion is also closely related to residual *** brinelling often occurrs with residual stress accomulation,meanwhile,the residual stress increases from 120 to 300 *** peeling occurs,residual stress is *** failure pattern transformed from false brinelling to fretting corrosion and is accompanied by *** far,none of investigation is able to show satisfactory evolution of oscillating-induced failures,this study may contribute to more scientific understanding of rolling bearings against long-

关键词： oscillating false brinelling fretting corrosion wear residual stress

Synchronous deprotonation–protonation for mechanically robust chitin/aramid nanofibers conductive aerogel with excellent pressure sensing, thermal management, and electromagnetic interference shielding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 2038-2049页

作者： xinxin Zhang Kunpeng Qian Jianhui Fang Sineenat Thaiboonrod miao miao xin Feng Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China School of Materials Sciences and Engineering Shanghai UniversityShanghai 200444China National Nanotechnology Center(NANOTEC) National Science and Technology Development Agency(NSTDA)Thailand Science ParkPathum Thani 12120Thailand

Aerogels with regularly porous structure and uniformly distributed conductive networks have received extensive attention in wearable electronic sensors,electromagnetic shielding,and so ***,the poor mechanical properties of the emerging nanofibers-based aerogels are limited in practical *** this work,we developed a synchronous deprotonation–protonation method in the KOH/dimethyl sulfoxide(DMSO)system at room temperature for achieving chitin cross-linked aramid nanofibers(CANFs)rather than chitin nanofibers(ChNFs)and aramid nanofibers(ANFs)separately by using chitin and aramid pulp as raw *** freeze-drying process,the cross-linked chitin/aramid nanofibers(CA)aerogel exhibited the synergetic properties of ChNF and ANF by the dual-nanofiber compensation *** mechanical stress of CA aerogel was 170 kPa at 80%compressive strain,increased by 750%compared with pure ChNF ***,the compressibility of CA aerogel was somewhat improved compared to ANF *** enhancement verified that the crosslinking reaction between ANF and ChNF during the synchronous deprotonation process was ***,the conductive aerogels with uniform porous structure(CA-M)were successfully obtained by vacuum impregnating CA aerogels in Ti_(3)C_(2)T_(x) MXene solution,displaying low thermal conductivity(0.01 W/(m·K)),high electromagnetic interference(EMI)shielding effectiveness(SE)(75 dB),flame retardant,and heat ***,the as-obtained CA-M aerogels were also applied as a pressure sensor with excellent compression cycle stability and superior human motion monitoring *** a result,the dual-nanofiber based conductive aerogels have great potentials in flexible/wearable electronics,EMI shielding,flame retardant,and heat insulation.

关键词： synchronous deprotonation–protonation electromagnetic interference(EMI)shielding flame retardant heat insulation pressure sensing

An adaptive large neighborhood search for the multi-point dynamic aggregation problem

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Control Theory and Technology 2024年第3期22卷 360-378页

作者： Shengyu Lu Bin xin Jie Chen miao Guo School of Automation Beijing Institute of TechnologyBeijing 100081China National Key Lab of Autonomous Intelligent Unmanned Systems Beijing 100081China Department of Control Science and Engineering Tongji UniversityShanghai 201804China

The multi-point dynamic aggregation(MPDA)problem is a challenging real-world *** the MPDA problem,the demands of tasks keep changing with their inherent incremental rates,while a heterogeneous robot fleet is required to travel between these tasks to change the time-varying state of each *** robots are allowed to collaborate on the same task or work separately until all tasks are *** is challenging to generate an effective task execution plan due to the tight coupling between robots abilities and tasks'incremental rates,and the complexity of robot *** effectiveness consideration,we use the variable length encoding to avoid redundancy in the solution *** creatively use the adaptive large neighborhood search(ALNS)framework to solve the MPDA *** the proposed algorithm,high-quality initial solutions are generated through multiple problem-specific solution construction *** heuristics are also used to fix the broken solution in the novel integrated decoding-construction repair process of the ALNS *** results of statistical analysis by the Wilcoxon rank-sum test demonstrate that the proposed ALNS can obtain better task execution plans than some state-of-the-art algorithms in most MPDA instances.

关键词： Adaptive large neighborhood search(ALNS) Multi-point dynamic aggregation(MPDA) Heuristic solution construction Multi-robot collaboration

From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2024年第1期34卷 66-73页

作者： miao chang Chiyao Tang Chong-Chen Wang Chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment