期刊文献+
共找到19,260篇文章
< 1 2 250 >
每页显示 20 50 100
A single micro-LED manipulation system based on micro-gripper 被引量:2
1
作者 Jie Bai Pingjuan Niu +2 位作者 Erdan Gu Jianming Li Clarence Augustine TH Tee 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期41-48,共8页
Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techni... Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays. 展开更多
关键词 MICRO-GRIPPER Micro-LED Transfer printing manipulation
下载PDF
Pre‑hatch thermal manipulation of embryos and post‑hatch baicalein supplementation mitigated heat stress in broiler chickens 被引量:1
2
作者 Sadid Al Amaz Ajay Chaudhary +2 位作者 Prem Lal Mahato Rajesh Jha Birendra Mishra 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1071-1085,共15页
Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some succes... Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some success in mitigating heat stress(HS)in broilers.Developing novel HS mitigation strategies for sustaining broiler production is critically needed.This study investigated the effects of pre-hatch thermal manipulation(TM)and post-hatch baica-lein supplementation on growth performance and health parameters in heat-stressed broilers.Results Six hundred fertile Cobb 500 eggs were incubated for 21 d.After candling on embryonic day(ED)10,238 eggs were thermally manipulated at 38.5℃ with 55%relative humidity(RH)from ED 12 to 18,then transferred to the hatcher(ED 19 to 21,standard temperature)and 236 eggs were incubated at a controlled temperature(37.5℃)till hatch.After hatch,180-day-old chicks from both groups were raised in 36 pens(n=10 birds/pen,6 replicates per treatment).The treatments were:1)Control,2)TM,3)control heat stress(CHS),4)thermal manipulation heat stress(TMHS),5)control heat stress supplement(CHSS),and 6)thermal manipulation heat stress supplement(TMHSS).All birds were raised under the standard environment for 21 d,followed by chronic heat stress from d 22 to 35(32–33℃ for 8 h)in the CHS,TMHS,CHSS,and TMHSS groups.A thermoneutral(22–24℃)environment was maintained in the Control and TM groups.RH was constant(50%±5%)throughout the trial.All the data were analyzed using one-way ANOVA in R and GraphPad software at P<0.05 and are presented as mean±SEM.Heat stress significantly decreased(P<0.05)the final body weight and ADG in CHS and TMHS groups compared to the other groups.Embryonic TM significantly increased(P<0.05)the expression of heat shock protein-related genes(HSP70,HSP90,and HSPH1)and antioxidant-related genes(GPX1 and TXN).TMHS birds showed a significant increment(P<0.05)in total cecal volatile fatty acid(VFA)concentration compared to the CHS birds.The cecal microbial analysis showed significant enrichment(P<0.05)in alpha and beta diversity and Coprococcus in the TMHSS group.Conclusions Pre-hatch TM and post-hatch baicalein supplementation in heat-stressed birds mitigate the detrimental effects of heat stress on chickens’growth performance,upregulate favorable gene expression,increase VFA produc-tion,and promote gut health by increasing beneficial microbial communities. 展开更多
关键词 BAICALEIN Growth performance Gut microbiota Heat stress Thermal manipulation
下载PDF
Many faces of neuronal activity manipulation in Drosophila
3
作者 Amber Krebs Steffen Kautzmann Christian Klämbt 《Neural Regeneration Research》 SCIE CAS 2025年第9期2574-2576,共3页
Animals exhibit complex responses to external and internal stimuli.The information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane potential.How can neuron... Animals exhibit complex responses to external and internal stimuli.The information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane potential.How can neuronal activity orchestrate complex motor patterns or allow learning from previous experience?To answer such questions,we need the ability not only to record,but also to modulate neuronal activity in both space(e.g.,neuronal subsets)and time. 展开更多
关键词 manipulation potential. NEURONAL
下载PDF
Optimization Control of Multi-Mode Coupling All-Wheel Drive System for Hybrid Vehicle
4
作者 Lipeng Zhang Zijian Wang +1 位作者 Liandong Wang Changan Ren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期340-355,共16页
The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy... The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy of hybrid vehicles becomes an issue.A unique multi-mode coupling(MMC)AWD hybrid system is presented to realize the distributed and centralized driving of the front and rear axles to achieve vectored distribution and full utilization of the system power between the axles of vehicles.Based on the parameters of the benchmarking model of a hybrid vehicle,the best model-predictive control-based energy management strategy is proposed.First,the drive system model was built after the analysis of the MMC-AWD’s drive modes.Next,three fundamental strategies were established to address power distribution adjustment and battery SOC maintenance when the SOC changed,which was followed by the design of a road driving force observer.Then,the energy consumption rate in the average time domain was processed before designing the minimum fuel consumption controller based on the equivalent fuel consumption coefficient.Finally,the advantage of the MMC-AWD was confirmed by comparison with the dynamic performance and economy of the BYD Song PLUS DMI-AWD.The findings indicate that,in comparison to the comparative hybrid system at road adhesion coefficients of 0.8 and 0.6,the MMC-AWD’s capacity to accelerate increases by 5.26%and 7.92%,respectively.When the road adhesion coefficient is 0.8,0.6,and 0.4,the maximum climbing ability increases by 14.22%,12.88%,and 4.55%,respectively.As a result,the dynamic performance is greatly enhanced,and the fuel savings rate per 100 km of mileage reaches 12.06%,which is also very economical.The proposed control strategies for the new hybrid AWD vehicle can optimize the power and economy simultaneously. 展开更多
关键词 Hybrid vehicle All-wheel drive multi-mode coupling Energy management Model predictive control
下载PDF
A 1-bit electronically reconfigurable beam steerable metasurface reflectarray with multiple polarization manipulations
5
作者 史琰 徐茜雅 +2 位作者 王少泽 魏文岳 武全伟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期384-394,共11页
A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the ... A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the two PIN diodes between ON and OFF states, the isotropic and anisotropic reflections can be flexibly achieved. For either the isotropic reflection or the anisotropic reflection, the two operation states achieve the reflection coefficients with approximately equal magnitude and 180°out of phase, thus giving rise to the isotropic/anisotropic 1-bit metasurface unit cells. With the 1-bit unit cells, a 12-by-12 metasurface reflectarray is optimally designed and fabricated. Under either y-or x-polarized incident wave illumination, the reflectarray can achieve the co-polarized and cross-polarized beam scanning, respectively, with the peak gains of 20.08 d Bi and 17.26 d Bi within the scan range of about ±50°. With the right-handed circular polarization(RHCP) excitation, the left-handed circular polarization(LHCP) radiation with the peak gain of 16.98 d Bic can be achieved within the scan range of ±50°. Good agreement between the experimental results and the simulation results are observed for 2D beam steering and polarization manipulation capabilities. 展开更多
关键词 electronically controlled metasurface reflectarray beam steering polarization manipulation
下载PDF
Fake News Detection Based on Text-Modal Dominance and Fusing Multiple Multi-Model Clues
6
作者 Li fang Fu Huanxin Peng +1 位作者 Changjin Ma Yuhan Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4399-4416,共18页
In recent years,how to efficiently and accurately identify multi-model fake news has become more challenging.First,multi-model data provides more evidence but not all are equally important.Secondly,social structure in... In recent years,how to efficiently and accurately identify multi-model fake news has become more challenging.First,multi-model data provides more evidence but not all are equally important.Secondly,social structure information has proven to be effective in fake news detection and how to combine it while reducing the noise information is critical.Unfortunately,existing approaches fail to handle these problems.This paper proposes a multi-model fake news detection framework based on Tex-modal Dominance and fusing Multiple Multi-model Cues(TD-MMC),which utilizes three valuable multi-model clues:text-model importance,text-image complementary,and text-image inconsistency.TD-MMC is dominated by textural content and assisted by image information while using social network information to enhance text representation.To reduce the irrelevant social structure’s information interference,we use a unidirectional cross-modal attention mechanism to selectively learn the social structure’s features.A cross-modal attention mechanism is adopted to obtain text-image cross-modal features while retaining textual features to reduce the loss of important information.In addition,TD-MMC employs a new multi-model loss to improve the model’s generalization ability.Extensive experiments have been conducted on two public real-world English and Chinese datasets,and the results show that our proposed model outperforms the state-of-the-art methods on classification evaluation metrics. 展开更多
关键词 Fake news detection cross-modal attention mechanism multi-modal fusion social network transfer learning
下载PDF
Image Retrieval with Text Manipulation by Local Feature Modification 被引量:2
7
作者 查剑宏 燕彩蓉 +1 位作者 张艳婷 王俊 《Journal of Donghua University(English Edition)》 CAS 2023年第4期404-409,共6页
The demand for image retrieval with text manipulation exists in many fields, such as e-commerce and Internet search. Deep metric learning methods are used by most researchers to calculate the similarity between the qu... The demand for image retrieval with text manipulation exists in many fields, such as e-commerce and Internet search. Deep metric learning methods are used by most researchers to calculate the similarity between the query and the candidate image by fusing the global feature of the query image and the text feature. However, the text usually corresponds to the local feature of the query image rather than the global feature. Therefore, in this paper, we propose a framework of image retrieval with text manipulation by local feature modification(LFM-IR) which can focus on the related image regions and attributes and perform modification. A spatial attention module and a channel attention module are designed to realize the semantic mapping between image and text. We achieve excellent performance on three benchmark datasets, namely Color-Shape-Size(CSS), Massachusetts Institute of Technology(MIT) States and Fashion200K(+8.3%, +0.7% and +4.6% in R@1). 展开更多
关键词 image retrieval text manipulation ATTENTION local feature modification
下载PDF
Multifunctional Perovskite Photodetectors: From Molecular-Scale Crystal Structure Design to Micro/Nano-scale Morphology Manipulation 被引量:2
8
作者 Yingjie Zhao Xing Yin +4 位作者 Pengwei Li Ziqiu Ren Zhenkun Gu Yiqiang Zhang Yanlin Song 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期565-594,共30页
Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implement... Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implementation of multifunctional detectors is based on the physical combination of optical lenses, gratings, and multiple photodetectors, the large size and its complex structure hinder the miniaturization, lightweight, and integration of devices. In contrast, perovskite materials have achieved remarkable progress in the field of multifunctional photodetectors due to their diverse crystal structures, simple morphology manipulation, and excellent optoelectronic properties. In this review, we first overview the crystal structures and morphology manipulation techniques of perovskite materials and then summarize the working mechanism and performance parameters of multifunctional photodetectors. Furthermore, the fabrication strategies of multifunctional perovskite photodetectors and their advancements are highlighted, including polarized light detection, spectral detection, angle-sensing detection, and selfpowered detection. Finally, the existing problems of multifunctional detectors and the perspectives of their future development are presented. 展开更多
关键词 Perovskite materials Crystal structure design Micro/nano-structure manipulation Working mechanism Multifunctional photodetectors
下载PDF
Lactation breast abscess treated with Gualou Xiaoyong decoction and painless lactation manipulation:A case report and review of literature 被引量:2
9
作者 Li-Hua Jin Hui-Ling Zheng +4 位作者 Yun-Xia Lin Yi Yang Jia-Li Liu Rui-Lan Li Hui-Jun Ye 《World Journal of Clinical Cases》 SCIE 2023年第8期1847-1856,共10页
BACKGROUND Breast abscess during lactation is a severe complication of acute mastitis,which can lead to discomfort,high fever,breast fistula,sepsis,septic shock,breast damage,disease persistence and frequent hospitali... BACKGROUND Breast abscess during lactation is a severe complication of acute mastitis,which can lead to discomfort,high fever,breast fistula,sepsis,septic shock,breast damage,disease persistence and frequent hospitalization.Breast abscesses may also lead the mother to discontinue breastfeeding,thereby harming the infant’s health.The predominant pathogenic bacteria are Staphylococcus aureus,Staphylococcus epidermidis and Streptococcus.The incidence of breastfeeding abscesses in breastfeeding women ranges between 4.0%and 11.0%.In cases of breast abscess,the rate of cessation of lactation is 41.0%.In instances of breast fistula,the rate of cessation of lactation is very high(66.7%).Furthermore,50.0%of women with breast abscesses must be hospitalized and treated with intravenous antibiotics.Treatment includes antibiotics,abscess puncture and surgical incision and drainage.The patients suffer from stress,pain and easily induced breast scarring;the disease’s progression is prolonged and recurrent,interfering with infant feeding.Consequently,it is crucial to discover an adequate cure.CASE SUMMARY A 28-year-old woman with a breast abscess was treated with Gualou Xiaoyong decoction and painless breast opening manipulation 24 d after cesarean delivery.On the 2nd d of treatment,the patient’s breast mass was significantly reduced,the pain was significantly reduced,and the general asthenia was improved.All conscious symptoms disappeared after 3 d,breast abscesses faded after 12 d of treatment,inflammation images disappeared after 27 d,and normal lactation images were restored.CONCLUSION In treating breast abscesses during breastfeeding,the combination of Gualou Xiaoyong decoction and painless lactation provides a positive therapeutic impact.This disease’s treatment offers the advantages of a short course of treatment,no need to discontinue breastfeeding and the ability to rapidly mitigate symptoms,which can be used as a reference in clinical practice. 展开更多
关键词 Lactation breast abscess Gualou Xiaoyong decoction Painless lactation manipulation Literature review Case report
下载PDF
Triboelectric‘electrostatic tweezers'for manipulating droplets on lubricated slippery surfaces prepared by femtosecond laser processing 被引量:2
10
作者 Jiale Yong Xinlei Li +5 位作者 Youdi Hu Yubin Peng Zilong Cheng Tianyu Xu Chaowei Wang Dong Wu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期411-426,共16页
The use of‘Electrostatic tweezers'is a promising tool for droplet manipulation,but it faces many limitations in manipulating droplets on superhydrophobic surfaces.Here,we achieve noncontact and multifunctional dr... The use of‘Electrostatic tweezers'is a promising tool for droplet manipulation,but it faces many limitations in manipulating droplets on superhydrophobic surfaces.Here,we achieve noncontact and multifunctional droplet manipulation on Nepenthes-inspired lubricated slippery surfaces via triboelectric electrostatic tweezers(TETs).The TET manipulation of droplets on a slippery surface has many advantages over electrostatic droplet manipulation on a superhydrophobic surface.The electrostatic field induces the redistribution of the charges inside the neutral droplet,which causes the triboelectric charged rod to drive the droplet to move forward under the electrostatic force.Positively or negatively charged droplets can also be driven by TET based on electrostatic attraction and repulsion.TET enables us to manipulate droplets under diverse conditions,including anti-gravity climb,suspended droplets,corrosive liquids,low-surface-tension liquids(e.g.ethanol with a surface tension of 22.3 mN·m^(-1)),different droplet volumes(from 100 nl to 0.5 ml),passing through narrow slits,sliding over damaged areas,on various solid substrates,and even droplets in an enclosed system.Various droplet-related applications,such as motion guidance,motion switching,droplet-based microreactions,surface cleaning,surface defogging,liquid sorting,and cell labeling,can be easily achieved with TETs. 展开更多
关键词 triboelectric electrostatic tweezer droplet manipulation slippery surface superhydrophobic surface femtosecond laser
下载PDF
The road toward Cd-safe rice:From mass selection to marker-assisted selection and genetic manipulation
11
作者 Liang Sun Yongjun Tan Caiyan Chen 《The Crop Journal》 SCIE CSCD 2023年第4期1059-1071,共13页
Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessiv... Rice is an important dietary source of the toxic mineral cadmium(Cd) for populations in which rice is the main staple food.When grown in agricultural soils that are contaminated with Cd,rice often accumulates excessive Cd into the grains,which is a serious threat to agricultural sustainability and human health.To limit Cd accumulation in rice grains,studies on the genetic basis of Cd accumulation in rice have been carried out extensively,and some low-Cd rice varieties have also been developed in recent years.However,the challenges in low-Cd rice breeding still exist because the outcomes of the current genetic improvements for low-Cd rice cannot fully meet the requirements for the development of Cd-safe rice at present.In this review,we outline the progress in understanding the physiological mechanisms and the genetic nature of Cd accumulation in rice and summarize the strategies and outcomes of low-Cd rice breeding over the past decade.By graphing the physiological mechanism of Cd transport in the rice plant,three key steps and some underlying genes are summarized and discussed.Also,two genetic features of the natural variation in rice grain-Cd accumulation,the phenotypic plasticity and subspecies divergence,and the potential genetic explanations for these features are also discussed.Finally,we summarize and discuss current progress and the potential issues in low-Cd rice breeding using different breeding strategies.We hope to propose strategies for future success in the breeding of low-Cd rice varieties over the next decade. 展开更多
关键词 RICE Cadmium-safe Cadmium-free Gene manipulation MAS
下载PDF
A Multi-mode Electronic Load Sensing Control Scheme with Power Limitation and Pressure Cut-off for Mobile Machinery
12
作者 Min Cheng Bolin Sun +1 位作者 Ruqi Ding Bing Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期157-170,共14页
In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are ... In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are integrated into the electronic controller only from the pump level,leading to the potential instability of the overall system.To solve this problem,a multi-mode electrohydraulic load sensing(MELS)control scheme is proposed especially considering the switching stability from the system level,which includes four working modes of flow control,load sensing,power limitation,and pressure control.Depending on the actual working requirements,the switching rules for the different modes and the switching direction(i.e.,the modes can be switched bilaterally or unilaterally)are defined.The priority of different modes is also defined,from high to low:pressure control,power limitation,load sensing,and flow control.When multiple switching rules are satisfied at the same time,the system switches to the control mode with the highest priority.In addition,the switching stability between flow control and pressure control modes is analyzed,and the controller parameters that guarantee the switching stability are obtained.A comparative study is carried out based on a test rig with a 2-ton hydraulic excavator.The results show that the MELS controller can achieve the control functions of proper flow supplement,power limitation,and pressure cut-off,which has good stability performance when switching between different control modes.This research proposes the MELS control method that realizes the stability of multi-mode switching of the hydraulic system of mobile machinery under different working conditions. 展开更多
关键词 Hydraulic control Load sensing multi-mode Power limitation Mobile machinery
下载PDF
Giant 2D Skyrmion Topological Hall Effect with Ultrawide Temperature Window and Low-Current Manipulation in 2D Room-Temperature Ferromagnetic Crystals
13
作者 张高节 罗清源 +8 位作者 文晓琨 武浩 杨丽 靳雯 李路吉 张佳 张文峰 舒海波 常海欣 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第11期131-138,共8页
The discovery and manipulation of topological Hall effect(THE),an abnormal magnetoelectric response mostly related to the Dzyaloshinskii–Moriya interaction(DMI),are promising for next-generation spintronic devices ba... The discovery and manipulation of topological Hall effect(THE),an abnormal magnetoelectric response mostly related to the Dzyaloshinskii–Moriya interaction(DMI),are promising for next-generation spintronic devices based on topological spin textures such as magnetic skyrmions.However,most skyrmions and THE are stabilized in a narrow temperature window either below or over room temperature with high critical current manipulation.It is still elusive and challenging to achieve large THE with both wide temperature window till room temperature and low critical current manipulation.Here,using controllable,naturally oxidized sub-20 and sub-10 nm 2D van der Waals room-temperature ferromagnetic Fe_(3)GaTe_(2-x)crystals,we report robust 2D skyrmion THE with ultrawide temperature window ranging in three orders of magnitude from 2 to 300 K,in combination with giant THE of~5.4μΩ·cm at 10 K and~0.15μΩ·cm at 300 K,which is 1–3 orders of magnitude larger than that of all known room-temperature 2D skyrmion systems.Moreover,room-temperature current-controlled THE is also realized with a low critical current density of~6.2×10^(5)A·cm^(-2).First-principles calculations unveil natural oxidation-induced highly enhanced 2D interfacial DMI reasonable for robust giant THE.This work paves the way to room-temperature electrically controlled 2D THE-based practical spintronic devices. 展开更多
关键词 TOPOLOGICAL manipulation magnetic
下载PDF
Theoretical investigation of F-P cavity mode manipulation by single gold nanoparticles
14
作者 史旭升 罗志强 +1 位作者 李志远 虞华康 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期74-78,共5页
The ability to manipulate microlaser is highly desirable towards high-performance optoelectronic devices.Here we demonstrate feasible mode manipulation of Fabry-Perot type microlasers of a perovskite nanowire via inco... The ability to manipulate microlaser is highly desirable towards high-performance optoelectronic devices.Here we demonstrate feasible mode manipulation of Fabry-Perot type microlasers of a perovskite nanowire via incorporation of single gold nanoparticles.The influences of resonant wavelength,quality factor and emission directions are successively investigated using a two-dimensional finite-difference time-domain method.It is found that blueshift of resonant wavelength could be achieved together with either promoted or degraded quality factor of the microlaser via single Au NPs with varied sizes.Unidirectional emission could also be realized which is favorable for on-chip integration.Our results provide useful reference for feasible manipulation of light-matter interactions and mode selection. 展开更多
关键词 MICROLASER mode manipulation gold nanoparticle
下载PDF
Helical particle manipulation based on power-exponent-phase acoustic vortices generated by a sector transducer array
15
作者 王青东 胡彦涛 +1 位作者 王胜利 李洪宇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期333-341,共9页
The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non... The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non-axisymmetric pressure distribution, the concept of power-exponent-phase was first introduced into the formation of AV beams, named “powerexponent-phase acoustic vortices(PAVs)” in this paper. Based on a ring-array of sector transducers, the helical distribution of the low-pressure valley in cross-sections of PAVs, which enables particles to move from a distant position to the center low-potential well along a certain spiral passageway, was proved theoretically. The particle manipulation behavior for PAVs with a power order of 2 is numerically modeled and experimentally confirmed. The results show that PAVs with a nonaxisymmetric spiral pressure distribution can be used to realize the directional transport of particles in an enlarged scope,suggesting prospective application potential in biomedical engineering. 展开更多
关键词 acoustic vortices power-exponent-phase spiral potential well sector transducer array particle manipulation
下载PDF
Multi-mode Multi-frequency GNSS-IR Combination System for Sea Level Retrieval
16
作者 Wenyue CHE Xiaolei WANG +1 位作者 Xiufeng HE Jin LIU 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期32-39,共8页
With the development of Global Navigation Satellite Systems(GNSS),geodetic GNSS receivers have been utilized to monitor sea levels using GNSS-Interferometry Reflectometry(GNSS-IR)technology.The multi-mode,multi-freque... With the development of Global Navigation Satellite Systems(GNSS),geodetic GNSS receivers have been utilized to monitor sea levels using GNSS-Interferometry Reflectometry(GNSS-IR)technology.The multi-mode,multi-frequency signals of GPS,GLONASS,Galileo,and Beidou can be used for GNSS-IR sea level retrieval,but combining these retrievals remains problematic.To address this issue,a GNSS-IR sea level retrieval combination system has been developed,which begins by analyzing error sources in GNSS-IR sea level retrieval and establishing and solving the GNSS-IR retrieval equation.This paper focuses on two key points:time window selection and equation stability.The stability of the retrieval combination equations is determined by the condition number of the coefficient matrix within the time window.The impact of ill-conditioned coefficient matrices on the retrieval results is demonstrated using an extreme case of SNR data with only ascending or descending trajectories.After determining the time window and removing ill-conditioned equations,the multi-mode,multi-frequency GNSS-IR retrieval is performed.Results from three International GNSS Service(IGS)stations show that the combination method produces high-precision,high-resolution,and high-reliability sea level retrieval combination sequences. 展开更多
关键词 GNSS-IR sea level retrieval multi-mode multi-frequency combination equation stability
下载PDF
Transverse manipulation of particles using Bessel beam of tunable size generated by cross-phase modulation
17
作者 乔响来 程雪梅 +3 位作者 张倩 张文定 任兆玉 白晋涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期747-753,共7页
We report on a method to achieve multiple microscopic particles being trapped and manipulated transversely by using a size-tunable Bessel beam generated by cross-phase modulation(XPM)based on the thermal nonlinear opt... We report on a method to achieve multiple microscopic particles being trapped and manipulated transversely by using a size-tunable Bessel beam generated by cross-phase modulation(XPM)based on the thermal nonlinear optical effect.The results demonstrate that multiple polystyrene particles can be stably trapped simultaneously,and the number of the trapped particles can be controlled by varying the trapping beam power.In addition,the trapped particles can be manipulated laterally with micron-level precision by changing the size of J_(0)Bessel beam.This work provides a simple but efficient way to trap and manipulate multiple particles simultaneously,which would have potential applications in many fields such as cell sorting and transportation. 展开更多
关键词 optical manipulation optical trapping J_(0)Bessel beam cross-phase modulation
下载PDF
A Survey on Stock Market Manipulation Detectors Using Artificial Intelligence
18
作者 Mohd Asyraf Zulkifley Ali Fayyaz Munir +1 位作者 Mohd Edil Abd Sukor Muhammad Hakimi Mohd Shafiai 《Computers, Materials & Continua》 SCIE EI 2023年第5期4395-4418,共24页
A well-managed financial market of stocks,commodities,derivatives,and bonds is crucial to a country’s economic growth.It provides confidence to investors,which encourages the inflow of cash to ensure good market liqu... A well-managed financial market of stocks,commodities,derivatives,and bonds is crucial to a country’s economic growth.It provides confidence to investors,which encourages the inflow of cash to ensure good market liquidity.However,there will always be a group of traders that aims to manipulate market pricing to negatively influence stock values in their favor.These illegal trading activities are surely prohibited according to the rules and regulations of every country’s stockmarket.It is the role of regulators to detect and prevent any manipulation cases in order to provide a trading platform that is fair and efficient.However,the complexity of manipulation cases has increased significantly,coupled with high trading volumes,which makes the manual observations of such cases by human operators no longer feasible.As a result,many intelligent systems have been developed by researchers all over the world to automatically detect various types of manipulation cases.Therefore,this review paper aims to comprehensively discuss the state-of-theart methods that have been developed to detect and recognize stock market manipulation cases.It also provides a concise definition of manipulation taxonomy,including manipulation types and categories,as well as some of the output of early experimental research.In summary,this paper provides a thorough review of the automated methods for detecting stock market manipulation cases. 展开更多
关键词 Artificial intelligence machine learning convolutional neural network recurrent neural network stock market manipulation
下载PDF
Adaptive Consistent Management to Prevent System Collapse on Shared Object Manipulation in Mixed Reality
19
作者 Jun Lee Hyun Kwon 《Computers, Materials & Continua》 SCIE EI 2023年第4期2025-2042,共18页
A concurrency control mechanism for collaborative work is akey element in a mixed reality environment. However, conventional lockingmechanisms restrict potential tasks or the support of non-owners, thusincreasing the ... A concurrency control mechanism for collaborative work is akey element in a mixed reality environment. However, conventional lockingmechanisms restrict potential tasks or the support of non-owners, thusincreasing the working time because of waiting to avoid conflicts. Herein, wepropose an adaptive concurrency control approach that can reduce conflictsand work time. We classify shared object manipulation in mixed reality intodetailed goals and tasks. Then, we model the relationships among goal,task, and ownership. As the collaborative work progresses, the proposedsystem adapts the different concurrency control mechanisms of shared objectmanipulation according to the modeling of goal–task–ownership. With theproposed concurrency control scheme, users can hold shared objects andmove and rotate together in a mixed reality environment similar to realindustrial sites. Additionally, this system provides MS Hololens and Myosensors to recognize inputs from a user and provides results in a mixed realityenvironment. The proposed method is applied to install an air conditioneras a case study. Experimental results and user studies show that, comparedwith the conventional approach, the proposed method reduced the number ofconflicts, waiting time, and total working time. 展开更多
关键词 Mixed reality upper body motion recognition shared object manipulation adaptive task concurrency control
下载PDF
Photo-responsive droplet manipulation slippery lubricant-infused porous surface with ultra-high durability
20
作者 刘泽志 张琛 +6 位作者 文通 李荟竹 高文萍 王新孔 赵伟 王凯歌 白晋涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期87-95,共9页
Photo-responsive slippery lubricant-infused porous surface(SLIPS) for droplet manipulation is flexible, noncontact and non-destructive in droplet manipulation, which has promising applications in flexible robotics, mi... Photo-responsive slippery lubricant-infused porous surface(SLIPS) for droplet manipulation is flexible, noncontact and non-destructive in droplet manipulation, which has promising applications in flexible robotics, microfluidics,biomedicine, and chemical analysis. However, the repeated manipulations for droplets of SLIPSs are quite limited in the works reported so far, the poor durability of droplet manipulation severely limits the practical application of the surfaces. In this paper, an Fe3O4-doped polydimethylsiloxane(PDMS)-based SLIPS is proposed and implemented to achieve ultra-high repeated droplet manipulation numbers under near-infrared ray(NIR) laser irradiation. Firstly, a micron columnar array structure with micro-pits on the top side, as well as, a wall structure out of the array is designed on SLIPS to reserve the lubricant. Secondly, the prototype of the SLIPS is fabricated by a 3-step ultraviolet(UV) lithography, and subsequently immersed in silicone oil for more than 96 h to obtain the ultra-high durability slippery lubricant-infused porous surface(UD-SLIPS). With a power of 25 m W–85 m W NIR laser, the repeated manipulation of microdroplets(≤ 5 μL) in the scale of 1 cm can exceed more than 3000 times which is far beyond that in previous reports. Finally, the droplet manipulation performance of this photo-responsive UD-SLIPS and the influence of infusion time on durability are investigated. The mechanism of the PDMS swelling effect is found to be the key factor in improving the droplet manipulation durability of SLIPS. The findings of this work would be of great significance for the development of highly durable photo-responsive functional surfaces for droplet manipulation. 展开更多
关键词 PHOTO-RESPONSIVE droplet manipulation slippery lubricant-infused porous surface(SLIPS) ultra-violet(UV)lithography
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部