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A Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller Model Combined with an Improved Particle Swarm Optimization Method for Fall Detection
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作者 Jyun-Guo Wang 《Computer Systems Science & Engineering》 2024年第5期1149-1170,共22页
In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible t... In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible to unsafe events(such as falls)that can have disastrous consequences.However,automatically detecting falls fromvideo data is challenging,and automatic fall detection methods usually require large volumes of training data,which can be difficult to acquire.To address this problem,video kinematic data can be used as training data,thereby avoiding the requirement of creating a large fall data set.This study integrated an improved particle swarm optimization method into a double interactively recurrent fuzzy cerebellar model articulation controller model to develop a costeffective and accurate fall detection system.First,it obtained an optical flow(OF)trajectory diagram from image sequences by using the OF method,and it solved problems related to focal length and object offset by employing the discrete Fourier transform(DFT)algorithm.Second,this study developed the D-IRFCMAC model,which combines spatial and temporal(recurrent)information.Third,it designed an IPSO(Improved Particle Swarm Optimization)algorithm that effectively strengthens the exploratory capabilities of the proposed D-IRFCMAC(Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller)model in the global search space.The proposed approach outperforms existing state-of-the-art methods in terms of action recognition accuracy on the UR-Fall,UP-Fall,and PRECIS HAR data sets.The UCF11 dataset had an average accuracy of 93.13%,whereas the UCF101 dataset had an average accuracy of 92.19%.The UR-Fall dataset had an accuracy of 100%,the UP-Fall dataset had an accuracy of 99.25%,and the PRECIS HAR dataset had an accuracy of 99.07%. 展开更多
关键词 Double interactively recurrent fuzzy cerebellar model articulation controller(D-IRFCMAC) improved particle swarm optimization(IPSO) fall detection
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From the new Austrian tunneling method to the geoengineering condition evaluation and dynamic controlling method 被引量:1
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作者 Yanjun Shang Kun Li +1 位作者 Wantong He Chunbo Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期366-372,共7页
The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with the... The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones). With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Compre- hensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained. 展开更多
关键词 Unfavorable geological body (UGB)Multi-factor interaction matrix Discontinuity dynamic controlling (DDC)Cut slope Geoengineering condition evaluation and dynamic controlling (GEDC) method
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Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer
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作者 Yanjun WANG Yunfei ZHANG +1 位作者 Shujun GAO Clarence W.DE SILVA 《Instrumentation》 2019年第4期2-13,共12页
For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type of interaction control.Specifically,in impedance control,... For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type of interaction control.Specifically,in impedance control,the dynamic relationship between the interaction force and the resulting motion is controlled.In order to control the impedance of a mechanical system,typically,the interaction force has to be sensed.Due to the inherent limitations of direct force sensing at the interaction site,in the present work,the interaction force is observed using robust observers.In particular,to enhance the accuracy of impedance control,a first order sliding mode impedance controller is designed and incorporated in the present paper.Its advantage over positionbased interaction control algorithms is demonstrated through experimentation.Experimental results are given to show the effectiveness of the proposed algorithms. 展开更多
关键词 Interaction control Impedance control Neural Networks Sliding Mode Observer Sliding Mode control
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Construction of Virtual Simulation Platform for Tourism 被引量:1
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作者 Shuang CHENG Qiuju XIE +4 位作者 Jingfu ZHU Ya GAO Shuang WANG Ruichen CHI Ruijian LIU 《Asian Agricultural Research》 2017年第2期44-46,58,共4页
This paper introduced the application of the WebGIS and virtual reality technology in the tourism industry and analyzed the existing problems in the tourism information system.Taking Daqing Oil Field Scenic Sport as a... This paper introduced the application of the WebGIS and virtual reality technology in the tourism industry and analyzed the existing problems in the tourism information system.Taking Daqing Oil Field Scenic Sport as an example,it introduced a method of constructing the virtual simulation platform for tourism based on the combination of WebGIS and virtual reality technology.Through the virtual simulation platform of Daqing Tourism Scenic Spot,it verified the design idea,methods,and technical feasibility of the virtual tourism system,and built a specific,feasible,and practical virtual simulation platform for tourism.It showed the bright prospects of virtual tourism development based on WebGIS and virtual reality technology. 展开更多
关键词 Virtual tourism WEBGIS Virtual reality technology Interactive control
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Key Role of Some Specific Occupied Molecular Orbitals of Short Chain n-Alkanes in Their Surface Tension and Reaction Rate Constants with Hydroxyl Radicals: DFT Study 被引量:2
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作者 Mikhail Yu Gorbachev Natalia N. Gorinchoy Ion Arsene 《International Journal of Organic Chemistry》 CAS 2021年第1期1-13,共13页
Basing on the DFT calculations we propose the new theoretical model which describes both the surface tension σ of the short chain n-alkanes at their normal boiling points and their reaction rate constants with hydrox... Basing on the DFT calculations we propose the new theoretical model which describes both the surface tension σ of the short chain n-alkanes at their normal boiling points and their reaction rate constants with hydroxyl radicals OH<span style="white-space:nowrap;">&bull;</span> (at 297 ± 2 K) on the basis of their molecular orbital electronic characteristics. It has been shown that intermolecular dispersion attraction within the surface liquid monolayer of these compounds, as well as their reaction rate constants k with OH<span style="white-space:nowrap;">&bull;</span> radicals are determined by the energies <em>E<sub>orb</sub></em> of the specific occupied molecular orbitals which are the same in the determination of both the above physico-chemical characteristics of the studied n-alkanes. The received regression equations confirm the theoretically found dependences between the quantities of σ and k and the module |<em>E<sub>orb</sub></em>|. For the compounds under study this fact indicates the key role of their electronic structure particularities in determination of both the physical (surface tension) and the chemical (reaction rate constants) properties. 展开更多
关键词 Surface Tension Reaction Rate Constants N-ALKANES Hydroxyl Radicals Dispersion Attraction Orbital controlled Interactions DFT Calculations
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Real-time Subsynchronous Control Interaction Monitoring Using Improved Intrinsic Time-scale Decomposition 被引量:1
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作者 Yang Wang Hanlu Yang +2 位作者 Xiaorong Xie Xiaomei Yang Guanrun Chen 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第3期816-826,共11页
In recent years,subsynchronous control interaction(SSCI)has frequently taken place in renewable-connected power systems.To counter this issue,utilities have been seeking tools for fast and accurate identification of S... In recent years,subsynchronous control interaction(SSCI)has frequently taken place in renewable-connected power systems.To counter this issue,utilities have been seeking tools for fast and accurate identification of SSCI events.The main challenges of SSCI monitoring are the time-varying nature and uncertain modes of SSCI events.Accordingly,this paper presents a simple but effective method that takes advantage of intrinsic time-scale decomposition(ITD).The main purpose is to improve the accuracy and robustness of ITD by incorporating the least-squares method.Results show that the proposed method strikes a good balance between dynamic performance and estimation accuracy.More importantly,the method does not require any prior information,and its performance is therefore not affected by the frequency constitution of the SSCI.Comprehensive comparative studies are conducted to demonstrate the usefulness of the method through synthetic signals,electromagnetic temporary program(EMTP)simulations,and field-recorded SSCI data.Finally,real-time simulation tests are conducted to show the feasibility of the method for real-time monitoring. 展开更多
关键词 Subsynchronous control interaction(SSCI) intrinsic time-scale decomposition(ITD) wind power system realtime monitoring
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Ultrashort optical solitons in the dispersion-decreasing fibers
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作者 戴朝卿 陈均朗 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期108-111,共4页
We derive analytical bright and dark solitons of the modified nonlinear Schroedinger equations with variable coefficients. Under constraint conditions between system parameters, the optical soliton transmission in the... We derive analytical bright and dark solitons of the modified nonlinear Schroedinger equations with variable coefficients. Under constraint conditions between system parameters, the optical soliton transmission in the dispersiondecreasing fibers can be exactly controlled by proper dispersion management. The analytical description of the interactions between the bright and dark solitons are first obtained. 展开更多
关键词 nonlinear SchrSdinger equation soliton interaction and control dispersion decreasing fibers
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Molecular Orbital Nature of Solubility of Shot Chain n-Alkanes in Water and Their Reaction Rate Constants with Nitronium Cations: A DFT Study
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作者 Mikhail Yu. Gorbachev Natalia N. Gorinchoy 《International Journal of Organic Chemistry》 CAS 2022年第2期92-101,共10页
The new theoretical models describe both the solubility S of the shot chain n-alkanes in water at 298.15 K, and their reaction rate constants k with nitronium cation NO<sub>2</sub><sup>+ </sup>... The new theoretical models describe both the solubility S of the shot chain n-alkanes in water at 298.15 K, and their reaction rate constants k with nitronium cation NO<sub>2</sub><sup>+ </sup>at 293.15 K on the basis of their molecular orbital characteristics. It is shown that both the quantities S and k are determined by the energies E<sub>orb</sub> of the specific virtual (for S) and occupied (for k) molecular orbitals of these n-alkanes. The obtained regression equations confirm the theoretically found dependences of S and k on the absolute value of E<sub>orb</sub>. This fact demonstrates that the electronic structure particularities of the studied n-alkanes play a crucial role in both their above-mentioned physicochemical properties. 展开更多
关键词 Solubility in Water Reaction Rate Constants N-ALKANES Nitronium Cations Orbital controlled Interactions DFT Calculations
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Surface plasmon polaritons induced reduced hacking
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作者 Bakhtawar Muhammad Haneef Humayun Khan 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期379-384,共6页
There is always need for secure transmission of information and simultaneously compact-size photonic circuits. This can be achieved if surface plasmon-polaritons(SPPs) are used as source of information, and the reduce... There is always need for secure transmission of information and simultaneously compact-size photonic circuits. This can be achieved if surface plasmon-polaritons(SPPs) are used as source of information, and the reduced hacking as the transmission phenomenon. In this article, an SPP-based reduced hacking scheme is presented at interface between atomic medium and metallic conductor. The SPP propagation is manipulated with conductivity of the metal. The delay or advance of the SPP is found to create nanosecond time gap which can be used for storing and sending the information safely. The reduced hacking is further modified with conductivity of the metal and the control parameters of the atomic medium. 展开更多
关键词 surface plasmons coherent control of atomic interactions with photons reduced hacking surface conductivity
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Ultrafast population transfer in a Λ-configuration level system driven by few-cycle laser pulses
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作者 张文静 谢小涛 +1 位作者 金璐玲 白晋涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期337-344,共8页
The feasibility of population transfer from a populated level via an intermediate state to the target level driven by few-cycle pulses is theoretically discussed. The processes of on- or far-resonance stimulated Raman... The feasibility of population transfer from a populated level via an intermediate state to the target level driven by few-cycle pulses is theoretically discussed. The processes of on- or far-resonance stimulated Raman scattering with sequential or simultaneous ultrashort pulses are investigated respectively. We find that the ultrashort pulses with about two optical cycles can be used to realize the population operation. This suggests that the population transfer can be completed in the femtosecond time scale. At the same time, our simulation shows that the signal of the carrier-envelope-phase-dependent effect can be enlarged due to quantum interference in some conditions. Our theoretic study may promote the research on the coherent control via ultrashort pulses in the related fields. 展开更多
关键词 ultrafast processes coherent control of atomic interactions with photons quantum state engineer-ing and measurements
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A practical PID variable stiffness control and its enhancement for compliant force-tracking interactions with unknown environments
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作者 ZHANG Xin ZHOU Hao +3 位作者 LIU JinGuo JU ZhaoJie LENG YuQuan YANG ChenGuang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第10期2882-2896,共15页
Compliant interaction control is a key technology for robots performing contact-rich manipulation tasks.The design of the compliant controller needs to consider the robot hardware because complex control algorithms ma... Compliant interaction control is a key technology for robots performing contact-rich manipulation tasks.The design of the compliant controller needs to consider the robot hardware because complex control algorithms may not be compatible with the hardware performance,especially for some industrial robots with low bandwidth sensors.This paper focuses on effective and easy-to-use compliant control algorithms for position/velocity-controlled robots.Inspired by human arm stiffness adaptation behavior,a novel variable target stiffness(NVTS)admittance control strategy is proposed for adaptive force tracking,in which a proportional integral derivative(PID)variable stiffness law is designed to update the stiffness coefficient of the admittance function by the force and position feedback.Meanwhile,its stability and force-tracking capability are theoretically proven.In addition,an impact compensator(Impc)is integrated into the NVTS controller to enhance its disturbance-suppression capability when the robot is subjected to strong vibration disturbances in complicated surface polishing tasks.The proposed controllers are validated through four groups of experimental tests using different robots and the corresponding results demonstrate that they have high-accuracy tracking capability and strong adaptability in unknown environments. 展开更多
关键词 compliant interaction control force tracking PID variable stiffness impact compensator unknown environments
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Interaction among controlling factors for landslides triggered by the 2008 Wenchuan, China Mw 7.9 earthquake 被引量:4
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作者 Lingling SHEN Chong XU Lianyou LIU 《Frontiers of Earth Science》 CSCD 2016年第2期264-273,共10页
The 12 May 2008 Mw 7.9 Wenchuan, China earthquake triggered about 200,000 landslides, which were controlled by a number of factors. This study examines five factors: slope angle, slope aspect, lithology, peak ground ... The 12 May 2008 Mw 7.9 Wenchuan, China earthquake triggered about 200,000 landslides, which were controlled by a number of factors. This study examines five factors: slope angle, slope aspect, lithology, peak ground acceleration (PGA), and fault side (relative position on the seismogenic fault, i.e., hanging wall or footwall), to determine how these factors control the co-seismic land- slide occurrence and whether one or more factors, acting alone or in concert, are involved in promoting or suppressing landslides. We performed a multi-factor statistical analysis using data from the 2008 Wenchuan earthquake. The results show that in the areas characterized by steep topography or where strong ground shaking occurred during the earthquake, there is a closer relation- ship between slope aspect and landslide number density (LND) than other areas. The relationship between lithology and LND values depends on PGA. In turn, the relationship between LND values and PGA is also influenced by lithology. In addition, the controlling effect of lithology on co-seismic landslides on the hanging wall of the seismogenic fault is greater than that on the footwall. Examining interactions among these factors can improve understanding of the mechanisms of co-seismic landslide occurrence. 展开更多
关键词 Wenchuan earthquake co-seismic landslides interaction among controlling factors statistical analysis
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Setpoint Feasibility and Stability of Wind Park Control Interactions at Weak Grids 被引量:2
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作者 Argüello Andrés 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2022年第6期1790-1796,共7页
The controllers of wind parks that are connected to weak grids can induce unstable oscillations near the fundamental frequency.Such phenomenon can be studied with equivalent impedances of the wind generators,which dep... The controllers of wind parks that are connected to weak grids can induce unstable oscillations near the fundamental frequency.Such phenomenon can be studied with equivalent impedances of the wind generators,which depend on their operational setpoints at the fundamental frequency.The feasibility of such setpoint,i.e.,solution to the power flow,does not depend on the control parameters.However,oscillations from unfeasible setpoints and control instabilities both occur at weak grids and near the fundamental frequency.This letter presents an exploratory study to map the conditions where both phenomena occur,using sensitivity studies comprising multiple setpoints and control parameter tunings.The results are visually presented as the regions which inform the configurations leading to unfeasible setpoints,and unstable control interaction scenarios.Amongst the results,it can be observed that the trajectory of the eigenvalues in the Nyquist plots towards an unfeasible setpoint approaches a fundamental frequency instability. 展开更多
关键词 control interaction impedance power quality resonance STABILITY wind generator
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Unsteady Behavior and Control of Vortices in Centrifugal Compressor 被引量:5
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作者 Yutaka Ohta Nobumichi Fujisawa 《Journal of Thermal Science》 SCIE EI CAS CSCD 2014年第5期401-411,共11页
Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this paper.In the case of high-flow operation of a centrifugal compressor w... Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this paper.In the case of high-flow operation of a centrifugal compressor with a vaned diffuser,a discrete frequency noise induced by interaction between the impeller-discharge flow and the diffuser vane,which appears most notably in the power spectra of the radiated noise,can be reduced using a tapered diffuser vane(TDV) without affecting the performance of the compressor.Twin longitudinal vortices produced by leakage flow passing through the tapered portion of the diffuser vane induce secondary flow in the direction of the blade surface and prevent flow separation from the leading edge of the diffuser.The use of a TDV can effectively reduce both the discrete frequency noise generated by the interaction between the impeller-discharge flow and the diffuser surface and the broadband turbulent noise component.In the case of low-flow operation,a leading-edge vortex(LEV) that forms on the shroud side of the suction surface near the leading edge of the diffuser increases significantly in size and blocks flow in the diffuser passage.The formation of an LEV may adversely affect the performance of the compressor and may cause the diffuser to stall.Using a one-side tapered diffuser vane to suppress the evolution of an LEV,the stable operating range of the compressor can be increased by more than 12 percent,and the pressure-rise characteristics of the compressor can be improved.The results of a supplementary examination of the structure and unsteady behavior of LEVs,conducted by means of detailed numerical simulations,are also presented. 展开更多
关键词 centrifugal compressor vortex control interaction tone noise noise reduction CFD DES analysis stability enhancement leading-edge vortex.
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Real-time interactive motion control of virtual human in virtual maintenance based on limited information
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作者 Xiangyang Li Zhili Zhang +1 位作者 Feng Liang Zhao Tong 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2015年第2期16-39,共24页
In order to provide a simple and efficient approach to perform the real-time interactive motion control of virtual human in virtual maintenance environment(VME),the motion control method of virtual human based on limi... In order to provide a simple and efficient approach to perform the real-time interactive motion control of virtual human in virtual maintenance environment(VME),the motion control method of virtual human based on limited input information is proposed.With the space position tracking system with only one sensor the action sequences and motion models of virtual human,the human motions and hand actions in VME are driven by the sensor data in stages and in real time through the transmission condition control in the process of maintenance operation.And the input data and information is processed based on the method of Kalman filtering and wavelet transforming to improve the control effects.An experimental VME is also established to validate the control efficiency,and the experiment results show that the space motion control of virtual human in VME can be performed based on limited information with proposed control strategy. 展开更多
关键词 Real-time interactive motion control virtual human virtual maintenance virtual maintenance environment limited information
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Generation of Bell states via Lyapunov control on a two-qubit system with an anisotropic XY Heisenberg interaction
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作者 FAN QiuBo 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第3期474-478,共5页
We demonstrate that an arbitrary Bell state can be achieved in a two qubit anisotropic Heisenberg XY chain via Lyapunov control. During the whole process, we only need to apply an external field along a given directio... We demonstrate that an arbitrary Bell state can be achieved in a two qubit anisotropic Heisenberg XY chain via Lyapunov control. During the whole process, we only need to apply an external field along a given direction to a single qubit. This control strategy is effective for all initial states in the four-dimensional Hilbert space where the target state is asymptotically stable. The effects of imperfections on the fidelity for the target state such as Gaussian leakage of local control and localized dephasing of individual spins are also considered. 展开更多
关键词 Bell state Lyapunov control Heisenberg interaction
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Effects of Vortex Generator on Cylindrical Protrusion Aerodynamics
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作者 Vignesh Ram P.S. Toshiaki Setoguchi Heuy Dong Kim 《Journal of Thermal Science》 SCIE EI CAS CSCD 2016年第1期7-12,共6页
Experimental and numerical studies were carried out to evaluate the effect of vortex generator on a small cylindrical protrusion at Mach number 2.0. The experiments were performed using the supersonic blow down wind t... Experimental and numerical studies were carried out to evaluate the effect of vortex generator on a small cylindrical protrusion at Mach number 2.0. The experiments were performed using the supersonic blow down wind tunnel on different heights of cylindrical protrusion with vortex generator placed ahead of them. The upstream and downstream flow around the cylindrical protrusion is influenced by vortex generator as is observed using both visualization and pressure measurement techniques. Numerical studies using three dimensional steady implicit formulations with standard k-ω turbulence model was performed. Results obtained through the present computation are compared with the experimental results at Mach 2.0. Good agreements between computation and experimental results have been achieved. The results indicate that the aerodynamic drag acting on cylindrical protrusion can be reduced by adopting vortex generator. 展开更多
关键词 Cylindrical protrusion Vortex generator Shock wave boundary layer interaction Drag control
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