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Exploration of Energy-Saving Technologies in Building Electrical System Design
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作者 Yong Zhang 《Journal of Electronic Research and Application》 2024年第4期28-33,共6页
Green energy conservation is the mainstream trend in the current development of the construction industry.The application of energy-saving technology in building electrical system design can effectively reduce energy ... Green energy conservation is the mainstream trend in the current development of the construction industry.The application of energy-saving technology in building electrical system design can effectively reduce energy consumption,avoid unnecessary energy consumption,and truly achieve energy conservation and environmental protection.Based on this,the article elaborates on the principles of energy-saving design in building electrical systems,and actively explores the application of energy-saving technologies from different perspectives such as optimizing power supply and distribution system design,adopting high-efficiency energy-saving lighting equipment,applying renewable energy,promoting smart home technology,and improving the efficiency of building electrical equipment. 展开更多
关键词 Building electrical system design energy-saving technology
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SOLIDWORKS Electrical在通过式脚踏封口机自动化改造设计中的应用
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作者 董改花 赵家硕 +1 位作者 王晓兰 郭秀华 《工业控制计算机》 2024年第6期90-92,共3页
小型企业塑封工艺中通过式脚踏封口机应用广泛,但在塑封重型工件时,工人操作非常费力且次品率高,无法保障塑封质量,为此对其进行机构优化与软硬件设计自动化改造。利用SOLIDWORKS Electrical快速建立3D虚拟电气配盘与生成各类BOM清单,... 小型企业塑封工艺中通过式脚踏封口机应用广泛,但在塑封重型工件时,工人操作非常费力且次品率高,无法保障塑封质量,为此对其进行机构优化与软硬件设计自动化改造。利用SOLIDWORKS Electrical快速建立3D虚拟电气配盘与生成各类BOM清单,大大缩短了研发周期,安装人员还可以根据虚拟电气装配路径进行准确安装。最终设计出结构合理,满足生产工艺要求的自动化装置,企业以极少改造成本提质增效,为机电一体化装置自动化设计提供了一个高效开发途径。 展开更多
关键词 脚踏封口机 自动化改造 SOLIDWORKS electrical
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Flexible and Robust Functionalized Boron Nitride/Poly(p‑Phenylene Benzobisoxazole)Nanocomposite Paper with High Thermal Conductivity and Outstanding Electrical Insulation 被引量:1
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作者 Lin Tang Kunpeng Ruan +3 位作者 Xi Liu Yusheng Tang Yali Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期423-437,共15页
With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature... With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation approach.The obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered structures.Itsλ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),respectively.Besides,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment. 展开更多
关键词 Poly(p-phenylene-2 6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity electrical insulation
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Green,Sustainable Architectural Bamboo with High Light Transmission and Excellent Electromagnetic Shielding as a Candidate for Energy-Saving Buildings 被引量:6
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作者 Jing Wang Xinyu Wu +5 位作者 Yajing Wang Weiying Zhao Yue Zhao Ming Zhou Yan Wu Guangbin Ji 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期209-224,共16页
Currently,light-transmitting,energy-saving,and electromagnetic shielding materials are essential for reducing indoor energy consumption and improving the electromagnetic environment.Here,we developed a cellulose compo... Currently,light-transmitting,energy-saving,and electromagnetic shielding materials are essential for reducing indoor energy consumption and improving the electromagnetic environment.Here,we developed a cellulose composite with excellent optical transmittance that retained the natural shape and fiber structure of bamboo.The modified whole bamboo possessed an impressive optical transmittance of approximately 60%at 6.23 mm,illuminance of 1000 luminance(lux),water absorption stability(mass change rate less than 4%),longitudinal tensile strength(46.40 MPa),and surface properties(80.2 HD).These were attributed to not only the retention of the natural circular hollow structure of the bamboo rod on the macro,but also the complete bamboo fiber skeleton template impregnated with UV resin on the micro.Moreover,a multilayered device consisting of translucent whole bamboo,transparent bamboo sheets,and electromagnetic shielding film exhibited remarkable heat insulation and heat preservation performance as well as an electromagnetic shielding performance of 46.3 dB.The impressive optical transmittance,mechanical properties,thermal performance,and electromagnetic shielding abilities combined with the renewable and sustainable nature,as well as the fast and efficient manufacturing process,make this bamboo composite material suitable for effective application in transparent,energy-saving,and electromagnetic shielding buildings. 展开更多
关键词 electromagnetic interference shielding Biomass material TRANSMITTANCE energy-saving BAMBOO
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Safety and effectiveness of neuromuscular electrical stimulation in cardiac surgery:A systematic review 被引量:1
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作者 Christos Kourek Marios Kanellopoulos +4 位作者 Vasiliki Raidou Michalis Antonopoulos Eleftherios Karatzanos Irini Patsaki Stavros Dimopoulos 《World Journal of Cardiology》 2024年第1期27-39,共13页
BACKGROUND Lack of mobilization and prolonged stay in the intensive care unit(ICU)are major factors resulting in the development of ICU-acquired muscle weakness(ICUAW).ICUAW is a type of skeletal muscle dysfunction an... BACKGROUND Lack of mobilization and prolonged stay in the intensive care unit(ICU)are major factors resulting in the development of ICU-acquired muscle weakness(ICUAW).ICUAW is a type of skeletal muscle dysfunction and a common complication of patients after cardiac surgery,and may be a risk factor for prolonged duration of mechanical ventilation,associated with a higher risk of readmission and higher mortality.Early mobilization in the ICU after cardiac surgery has been found to be low with a significant trend to increase over ICU stay and is also associated with a reduced duration of mechanical ventilation and ICU length of stay.Neuromuscular electrical stimulation(NMES)is an alternative modality of exercise in patients with muscle weakness.A major advantage of NMES is that it can be applied even in sedated patients in the ICU,a fact that might enhance early mobilization in these patients.AIM To evaluate safety,feasibility and effectiveness of NMES on functional capacity and muscle strength in patients before and after cardiac surgery.METHODS We performed a search on Pubmed,Physiotherapy Evidence Database(PEDro),Embase and CINAHL databases,selecting papers published between December 2012 and April 2023 and identified published randomized controlled trials(RCTs)that included implementation of NMES in patients before after cardiac surgery.RCTs were assessed for methodological rigor and risk of bias via the PEDro.The primary outcomes were safety and functional capacity and the secondary outcomes were muscle strength and function.RESULTS Ten studies were included in our systematic review,resulting in 703 participants.Almost half of them performed NMES and the other half were included in the control group,treated with usual care.Nine studies investigated patients after cardiac surgery and 1 study before cardiac surgery.Functional capacity was assessed in 8 studies via 6MWT or other indices,and improved only in 1 study before and in 1 after cardiac surgery.Nine studies explored the effects of NMES on muscle strength and function and,most of them,found increase of muscle strength and improvement in muscle function after NMES.NMES was safe in all studies without any significant complication.CONCLUSION NMES is safe,feasible and has beneficial effects on muscle strength and function in patients after cardiac surgery,but has no significant effect on functional capacity. 展开更多
关键词 Neuromuscular electrical stimulation Cardiac surgery coronary artery bypass grafting Heart valve replacement Peak VO2 SAFETY
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Optimal transcorneal electrical stimulation parameters for preserving photoreceptors in a mouse model of retinitis pigmentosa
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作者 Sam Enayati Karen Chang +10 位作者 Anton Lennikov Menglu Yang Cherin Lee Ajay Ashok Farris Elzaridi Christina Yen Kasim Gunes Jia Xie Kin-Sang Cho Tor Paaske Utheim Dong Feng Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2543-2552,共10页
Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors,leading to progressive photoreceptor loss.Previous research supports the beneficial effect of electrical stimulation on pho... Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors,leading to progressive photoreceptor loss.Previous research supports the beneficial effect of electrical stimulation on photoreceptor survival.This study aims to identify the most effective electrical stimulation parameters and functional advantages of transcorneal electrical stimulation(tcES)in mice affected by inherited retinal degeneration.Additionally,the study seeked to analyze the electric field that reaches the retina in both eyes in mice and post-mortem humans.In this study,we recorded waveforms and voltages directed to the retina during transcorneal electrical stimulation in C57BL/6J mice using an intraocular needle probe with rectangular,sine,and ramp waveforms.To investigate the functional effects of electrical stimulation on photoreceptors,we used human retinal explant cultures and rhodopsin knockout(Rho^(-/-))mice,demonstrating progressive photoreceptor degeneration with age.Human retinal explants isolated from the donors’eyes were then subjected to electrical stimulation and cultured for 48 hours to simulate the neurodegenerative environment in vitro.Photoreceptor density was evaluated by rhodopsin immunolabeling.In vivo Rho^(-/-)mice were subjected to two 5-day series of daily transcorneal electrical stimulation using rectangular and ramp waveforms.Retinal function and visual perception of mice were evaluated by electroretinography and optomotor response(OMR),respectively.Immunolabeling was used to assess the morphological and biochemical changes of the photoreceptor and bipolar cells in mouse retinas.Oscilloscope recordings indicated effective delivery of rectangular,sine,and ramp waveforms to the retina by transcorneal electrical stimulation,of which the ramp waveform required the lowest voltage.Evaluation of the total conductive resistance of the post-mortem human compared to the mouse eyes indicated higher cornea-to-retina resistance in human eyes.The temperature recordings during and after electrical stimulation indicated no significant temperature change in vivo and only a subtle temperature increase in vitro(~0.5-1.5°C).Electrical stimulation increased photoreceptor survival in human retinal explant cultures,particularly at the ramp waveform.Transcorneal electrical stimulation(rectangular+ramp)waveforms significantly improved the survival and function of S and M-cones and enhanced visual acuity based on the optomotor response results.Histology and immunolabeling demonstrated increased photoreceptor survival,improved outer nuclear layer thickness,and increased bipolar cell sprouting in Rho^(-/-)mice.These results indicate that transcorneal electrical stimulation effectively delivers the electrical field to the retina,improves photoreceptor survival in both human and mouse retinas,and increases visual function in Rho^(-/-)mice.Combined rectangular and ramp waveform stimulation can promote photoreceptor survival in a minimally invasive fashion. 展开更多
关键词 bipolar cells electrical stimulation NEUROPROTECTION photoreceptor degeneration RETINA retinal explants retinitis pigmentosa transcorneal electrical stimulation WAVEFORM
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Energy-Saving Distributed Flexible Job Shop Scheduling Optimization with Dual Resource Constraints Based on Integrated Q-Learning Multi-Objective Grey Wolf Optimizer
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作者 Hongliang Zhang Yi Chen +1 位作者 Yuteng Zhang Gongjie Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1459-1483,共25页
The distributed flexible job shop scheduling problem(DFJSP)has attracted great attention with the growth of the global manufacturing industry.General DFJSP research only considers machine constraints and ignores worke... The distributed flexible job shop scheduling problem(DFJSP)has attracted great attention with the growth of the global manufacturing industry.General DFJSP research only considers machine constraints and ignores worker constraints.As one critical factor of production,effective utilization of worker resources can increase productivity.Meanwhile,energy consumption is a growing concern due to the increasingly serious environmental issues.Therefore,the distributed flexible job shop scheduling problem with dual resource constraints(DFJSP-DRC)for minimizing makespan and total energy consumption is studied in this paper.To solve the problem,we present a multi-objective mathematical model for DFJSP-DRC and propose a Q-learning-based multi-objective grey wolf optimizer(Q-MOGWO).In Q-MOGWO,high-quality initial solutions are generated by a hybrid initialization strategy,and an improved active decoding strategy is designed to obtain the scheduling schemes.To further enhance the local search capability and expand the solution space,two wolf predation strategies and three critical factory neighborhood structures based on Q-learning are proposed.These strategies and structures enable Q-MOGWO to explore the solution space more efficiently and thus find better Pareto solutions.The effectiveness of Q-MOGWO in addressing DFJSP-DRC is verified through comparison with four algorithms using 45 instances.The results reveal that Q-MOGWO outperforms comparison algorithms in terms of solution quality. 展开更多
关键词 Distributed flexible job shop scheduling problem dual resource constraints energy-saving scheduling multi-objective grey wolf optimizer Q-LEARNING
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Patterning single-layer materials by electrical breakdown using atomic force microscopy
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作者 Yajie Yang Jiajia Lu +1 位作者 Yanbo Xie Libing Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期71-77,共7页
The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patte... The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling nanodevices.Demonstrated here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on demand.This can be achieved by voltage scanning or applying a constant voltage while moving the tip.By measuring the electrical current,the formation process on single-layer materials was shown quantitatively.The present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further confirmation is still needed.The proposed method holds promise as a general nanomachining technology for the future. 展开更多
关键词 2D material NANOPATTERN AFM electrical breakdown LITHOGRAPHY
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Characterization of Aquifers in Crystalline and Crystallophyll Basement Zones Using the Electrical Resistivity Method (Trails and Electrical Soundings) in the Gagnoa Region, (Central-Western Côte d’Ivoire)
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作者 Oscar Zahibo Onétié Assoué Kouakou Sylvestre Kouadio +1 位作者 Kotchi Rodrigue Orou Maxime Assa Abe 《International Journal of Geosciences》 CAS 2024年第6期511-523,共13页
Introduction: Located in the central-western part of Côte d’Ivoire, the subsoil of the Gagnoa region is made up of sedimentary volcano formations and granitoids with developed fracturing. This complex Precambria... Introduction: Located in the central-western part of Côte d’Ivoire, the subsoil of the Gagnoa region is made up of sedimentary volcano formations and granitoids with developed fracturing. This complex Precambrian basement contains most of the region’s water resources. This is at the origin of the high failure rate during the various hydrogeological prospecting campaigns. Methodology: The database consists of resistivities from 42 holes and 51 trails drilled as part of the implementation of high-throughput drilling in the study area. The objective of this study is to deepen the knowledge of the fissured basement by interpreting profile curves and electrical soundings. It will be a question of classifying the different types of anomalies obtained on the profiles and their shapes. The orientation of the lineaments observed on the profiles was determined. Results: The interpretation of the geophysical data revealed various anomalies, the main ones being of the CC (Conductor Compartment) and CEDP (Contact between two bearings) types. These types of anomalies are mainly expressed in various forms: the “V”, “W” and “U” shapes. From these anomalies and the appearance of the electrical profiles, lineaments and their orientations were identified with N90-100, N130-140, N170-180 as major orientations. Conclusion: These results could contribute to a better understanding of the fractured environment of the Gagnoa region. 展开更多
关键词 BASEMENT electrical Profiles Sounding Curves Resistivities
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Electrospinning-hot pressing technique for the fabrication of thermal and electrical storage membranes and its applications
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作者 Panpan Che Baoshan Xie +7 位作者 Penghui Cao Youfu Lv Daifei Liu Huali Zhu Xianwen Wu Zhangxing He Jian Chen Chuanchang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期1945-1964,共20页
The combination of electrospinning and hot pressing,namely the electrospinning-hot pressing technique(EHPT),is an efficient and convenient method for preparing nanofibrous composite materials with good energy storage ... The combination of electrospinning and hot pressing,namely the electrospinning-hot pressing technique(EHPT),is an efficient and convenient method for preparing nanofibrous composite materials with good energy storage performance.The emerging composite membrane prepared by EHPT,which exhibits the advantages of large surface area,controllable morphology,and compact structure,has attracted immense attention.In this paper,the conduction mechanism of composite membranes in thermal and electrical energy storage and the performance enhancement method based on the fabrication process of EHPT are systematically discussed.Moreover,the state-of-the-art applications of composite membranes in these two fields are introduced.In particular,in the field of thermal energy storage,EHPT-prepared membranes have longitudinal and transverse nanofibers,which generate unique thermal conductivity pathways;also,these nanofibers offer enough space for the filling of functional materials.Moreover,EHPT-prepared membranes are beneficial in thermal management systems,building energy conservation,and electrical energy storage,e.g.,improving the electrochemical properties of the separators as well as their mechanical and thermal stability.The application of electrospinning-hot pressing membranes on capacitors,lithium-ion batteries(LIBs),fuel cells,sodium-ion batteries(SIBs),and hydrogen bromine flow batteries(HBFBs)still requires examination.In the future,EHPT is expected to make the field more exciting through its own technological breakthroughs or be combined with other technologies to produce intelligent materials. 展开更多
关键词 electrospinning-hot pressing technique thermal storage electrical storage composite membranes NANOFIBER
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GLOBAL UNIQUE SOLUTIONS FOR THE INCOMPRESSIBLE MHD EQUATIONS WITH VARIABLE DENSITY AND ELECTRICAL CONDUCTIVITY
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作者 Xueli KE 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1747-1765,共19页
We study the global unique solutions to the 2-D inhomogeneous incompressible MHD equations,with the initial data(u0,B0)being located in the critical Besov space■and the initial densityρ0 being close to a positive co... We study the global unique solutions to the 2-D inhomogeneous incompressible MHD equations,with the initial data(u0,B0)being located in the critical Besov space■and the initial densityρ0 being close to a positive constant.By using weighted global estimates,maximal regularity estimates in the Lorentz space for the Stokes system,and the Lagrangian approach,we show that the 2-D MHD equations have a unique global solution. 展开更多
关键词 inhomogeneous MHD equations electrical conductivity global unique solutions
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Electrically controllable spin filtering in zigzag phosphorene nanoribbon based normal–antiferromagnet–normal junctions
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作者 李锐岗 刘军丰 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期666-670,共5页
We investigated the electric controllable spin-filtering effect in a zigzag phosphorene nanoribbon(ZPNR) based normal–antiferromagnet–normal junction. Two ferromagnets are closely coupled to the edges of the nanorib... We investigated the electric controllable spin-filtering effect in a zigzag phosphorene nanoribbon(ZPNR) based normal–antiferromagnet–normal junction. Two ferromagnets are closely coupled to the edges of the nanoribbon and form the edge-to-edge antiferromagnetism. Under an in-plane electric field, the two degenerate edge bands of the edge-to-edge antiferromagnet split into four spin-polarized sub-bands and a 100% spin-polarized current can be easily induced with the maximal conductance 2e~2/h. The spin polarization changes with the strength of the electric field and the exchange field,and changes sign at opposite electric fields. The spin-polarized current switches from one edge to the other by reversing the direction of the electric field. The edge current can also be controlled spatially by changing the electric potential of the scattering region. The manipulation of edge current is useful in spin-transfer-torque magnetic random-access memory and provides a practical way to develop controllable spintronic devices. 展开更多
关键词 zigzag phosphorene electrically controllable spin filter quantum transport
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An Improved Solov2 Based on Attention Mechanism and Weighted Loss Function for Electrical Equipment Instance Segmentation
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作者 Junpeng Wu Zhenpeng Liu +2 位作者 Xingfan Jiang Xinguang Tao Ye Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期677-694,共18页
The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology pro... The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology provided by deep learning-based video surveillance for unmanned inspection of electrical equipment,this paper uses the bottleneck attention module(BAM)attention mechanism to improve the Solov2 model and proposes a new electrical equipment segmentation mode.Firstly,the BAM attention mechanism is integrated into the feature extraction network to adaptively learn the correlation between feature channels,thereby improving the expression ability of the feature map;secondly,the weighted sum of CrossEntropy Loss and Dice loss is designed as the mask loss to improve the segmentation accuracy and robustness of the model;finally,the non-maximal suppression(NMS)algorithm to better handle the overlap problem in instance segmentation.Experimental results show that the proposed method achieves an average segmentation accuracy of mAP of 80.4% on three types of electrical equipment datasets,including transformers,insulators and voltage transformers,which improve the detection accuracy by more than 5.7% compared with the original Solov2 model.The segmentation model proposed can provide a focusing technical means for the intelligent management of power systems. 展开更多
关键词 Deep learning electrical equipment attention mechanism weighted loss function
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Optimization Method for Electrical Water Heaters Considering Shifting Potentials of Electricity Consumption and Water-use Activities
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作者 Yuqing Bao Zhonghui Zuo Xuehua Wu 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2024年第4期1250-1259,共10页
Electrical water heaters(EWHs)are important can-didates to provide demand-response services.The traditional op-timization method for EWHs focuses on the optimization of the electricity consumption,without considering ... Electrical water heaters(EWHs)are important can-didates to provide demand-response services.The traditional op-timization method for EWHs focuses on the optimization of the electricity consumption,without considering the shifting poten-tial of the water-use activities.This paper proposes an optimiza-tion method for EWHs considering the shifting potentials of both the electricity consumption and water-use activities.Con-sidering that the water-use activities could be monolithically shifted,the shifting model of the water-use activities was devel-oped.In addition to the thermodynamic model of the EWH,the optimal scheduling model of the EWH was developed and solved using mixed-integer linear programming.Case studies were performed on a single EWH and aggregate EWHs,demon-strating that the proposed method can shift the water-use activi-ties and therefore increase the load-shifting potential of the EWHs. 展开更多
关键词 electrical water heater(EWH) demand response load-shifting water-use activity
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Damage Evolution of Ballastless Track Concrete Exposed to Flexural Fatigue Loads:The Application of Ultrasonic Pulse Velocity,Impact-echo and Surface Electrical Resistance Method
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作者 杨志强 李化建 +4 位作者 WEN Jiaxing DONG Haoliang HUANG Fali WANG Zhen YI Zhonglai 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期353-363,共11页
In order to clarify the fatigue damage evolution of concrete exposed to flexural fatigue loads,ultrasonic pulse velocity(UPV),impact-echo technology and surface electrical resistance(SR) method were used.Damage variab... In order to clarify the fatigue damage evolution of concrete exposed to flexural fatigue loads,ultrasonic pulse velocity(UPV),impact-echo technology and surface electrical resistance(SR) method were used.Damage variable based on the change of velocity of ultrasonic pulse(Du) and impact elastic wave(Di)were defined according to the classical damage theory.The influences of stress level,loading frequency and concrete strength on damage variable were measured.The experimental results show that Du and Di both present a three-stages trend for concrete exposed to fatigue loads.Since impact elastic wave is more sensitive to the microstructure damage in stage Ⅲ,the critical damage variable,i e,the damage variable before the final fracture of concrete of Di is slightly higher than that of Du.Meanwhile,the evolution of SR of concrete exposed to fatigue loads were analyzed and the relationship between SR and Du,SR and Di of concrete exposed to fatigue loads were established.It is found that the SR of concrete was decreased with the increasing fatigue cycles,indicating that surface electrical resistance method can also be applied to describe the damage of ballastless track concrete exposed to fatigue loads. 展开更多
关键词 ballastless track fatigue damage ultrasonic pulse velocity IMPACT-ECHO surface electrical resistance
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Extrusion 3D printing of carbon nanotube-assembled carbon aerogel nanocomposites with high electrical conductivity
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作者 Lukai Wang Jing Men +4 位作者 Junzong Feng Yonggang Jiang Liangjun Li Yijie Hu Jian Feng 《Nano Materials Science》 EI CAS CSCD 2024年第3期312-319,共8页
Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shapi... Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric features.Herein,a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon(CNT/C)aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks,in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer microgels.After extrusion printing,the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic geometries.Benefiting from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases,3D-printed CNT/C aerogels exhibit enhanced mechanical strength(fracture strength,0.79 MPa)and typical porous structure characteristics,including low density(0.220 g cm^(-3)),high surface area(298.4 m^(2)g^(-1)),and concentrated pore diameter distribution(~32.8nm).More importantly,CNT nanofibers provide an efficient electron transport pathway,imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 S cm^(-1).Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing. 展开更多
关键词 Carbon aerogel Extrusion 3D printing Carbon nanotube electrical conductivity RHEOLOGY
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Improving the electrical performances of InSe transistors by interface engineering
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作者 曹天俊 郝松 +5 位作者 吴晨晨 潘晨 戴玉頔 程斌 梁世军 缪峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期153-158,共6页
InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hinder... InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hindered due to its sensitivity to interfaces.In this study,we have achieved notable enhancement in the electrical performance of InSe transistors through interface engineering.We engineered an InSe/h-BN heterostructure,effectively suppressing dielectric layer-induced scattering.Additionally,we successfully established excellent metal-semiconductor contacts using graphene ribbons as a buffer layer.Through a methodical approach to interface engineering,our graphene/InSe/h-BN transistor demonstrates impressive on-state current,field-effect mobility,and on/off ratio at room temperature,reaching values as high as 1.1 mA/μm,904 cm^(2)·V^(-1)·s^(-1),and>10~6,respectively.Theoretical computations corroborate that the graphene/InSe heterostructure shows significant interlayer charge transfer and weak interlayer interaction,contributing to the enhanced performance of InSe transistors.This research offers a comprehensive strategy to elevate the electrical performance of InSe transistors,paving the way for their utilization in future electronic applications. 展开更多
关键词 two-dimensional materials INSE van der Waals heterostructure electrical performances charge density difference
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Structure and electrical properties of polysilicon films doped with ammonium tetraborate tetrahydrate
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作者 Yehua Tang Yuchao Wang +1 位作者 Chunlan Zhou Ke-Fan Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第10期60-68,共9页
Here,p-type polysilicon films are fabricated by ex-situ doping method with ammonium tetraborate tetrahydrate(ATT)as the boron source,named ATT-pPoly.The effects of ATT on the properties of polysilicon films are compre... Here,p-type polysilicon films are fabricated by ex-situ doping method with ammonium tetraborate tetrahydrate(ATT)as the boron source,named ATT-pPoly.The effects of ATT on the properties of polysilicon films are comprehensively analyzed.The Raman spectra reveal that the ATT-pPoly film is composed of grain boundary and crystalline regions.The preferred orientation is the(111)direction.The grain size increases from 16−23 nm to 21−47 nm,by~70%on average.Comparing with other reported films,Hall measurements reveal that the ATT-pPoly film has a higher carrier concentration(>10^(20)cm^(−3))and higher carrier mobility(>30 cm2/(V·s)).The superior properties of the ATT-pPoly film are attributed to the heavy doping and improved grain size.Heavy doping property is proved by the mean sheet resistance(Rsheet,m)and distribution profile.The R_(sheet,m)decreases by more than 30%,and it can be further decreased by 90%if the annealing temperature or duration is increased.The boron concentration of ATT-pPoly film annealed at 950℃ for 45 min is~3×10^(20)cm^(−3),and the distribution is nearly the same,except near the surface.Besides,the standard deviation coefficient(σ)of Rsheet,m is less than 5.0%,which verifies the excellent uniformity of ATT-pPoly film. 展开更多
关键词 polysilicon film boron doping ammonium tetraborate tetrahydrate(ATT) electrical properties CRYSTALLIZATION
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Study on theoretical model for electrical explosion resistivity of Al/Ni reactive multilayer foil
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作者 Zehao Wang Tao Wang +2 位作者 Pengfei Xue Mingyu Li Qingxuan Zeng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期348-356,共9页
Al/Ni reactive multilayer foil(RMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/Ni RMF was developed to guide the optimization ... Al/Ni reactive multilayer foil(RMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/Ni RMF was developed to guide the optimization of EFIs.Al/Ni RMF with different bilayer thicknesses and bridge dimensions were prepared by MEMS technology and electrical explosion tests were carried out.According to physical and chemical reactions in bridge,the electrical explosion process was divided into 5 stages:heating of condensed bridge,vaporization and diffusion of Al layers,intermetallic combination reaction,intrinsic explosion,ionization of metal gases,which are obviously shown in measured voltage curve.Effects of interface and grain boundary scattering on the resistivity of film metal were considered.Focusing on variations of substance and state,the resistivity was developed as a function of temperature at each stage.Electrical explosion curves were calculated by this model at different bilayer thicknesses,bridge dimensions and capacitor voltages,which showed an excellent agreement with experimental ones. 展开更多
关键词 Al/Ni reactive multilayer foil electrical explosion Resistivity model Phase transition CALCULATION
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Impact of transcranial electrical stimulation on serum neurotrophic factors and language function in patients with speech disorders
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作者 Li Sun Kai Xiao +1 位作者 Xiao-Yan Shen Shu Wang 《World Journal of Clinical Cases》 SCIE 2024年第10期1742-1749,共8页
BACKGROUND Speech disorders have a substantial impact on communication abilities and quality of life.Traditional treatments such as speech and psychological therapies frequently demonstrate limited effectiveness and p... BACKGROUND Speech disorders have a substantial impact on communication abilities and quality of life.Traditional treatments such as speech and psychological therapies frequently demonstrate limited effectiveness and patient compliance.Transcranial electrical stimulation(TES)has emerged as a promising non-invasive treatment to improve neurological functions.However,its effectiveness in enhancing language functions and serum neurofactor levels in individuals with speech disorders requires further investigation.AIM To investigate the impact of TES in conjunction with standard therapies on serum neurotrophic factor levels and language function in patients with speech disorders.METHODS In a controlled study spanning from March 2019 to November 2021,81 patients with speech disorders were divided into a control group(n=40)receiving standard speech stimulation and psychological intervention,and an observation group(n=41)receiving additional TES.The study assessed serum levels of ciliary neurotrophic factor(CNTF),glial cell-derived neurotrophic factor(GDNF),brainderived neurotrophic factor(BDNF),and nerve growth factor(NGF),as well as evaluations of motor function,language function,and development quotient scores.RESULTS After 3 wk of intervention,the observation group exhibited significantly higher serum levels of CNTF,GDNF,BDNF,and NGF compared to the control group.Moreover,improvements were noted in motor function,cognitive function,language skills,physical abilities,and overall development quotient scores.It is worth mentioning that the observation group also displayed superior perfor CONCLUSION This retrospective study concluded that TES combined with traditional speech and psychotherapy can effectively increase the levels of neurokines in the blood and enhance language function in patients with speech disorders.These results provide a promising avenue for integrating TES into standard treatment methods for speech disorders. 展开更多
关键词 Transcranial electrical stimulation Serum neurofactor levels Developmental level Language features
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