When the ultra-high-speed elevator car-counterweight system runs opposite each other, significant piston effects are caused, seriously affecting operation's stability. In order to explore aerodynamic characteristics of whole operation process a under multi-parameters, this study first establishes three-dimensional transient model and multi-region dynamic layering numerical simulation method based on is proposed. Then, actual experiment validates correctness method. Finally, influence rules...

Significant piston effects occur when the high-speed elevator double car systems operate in opposition. Particularly, two intersect, aerodynamic forces operating on undergo an immediate alteration, significantly affecting stability of operation. This research aims to examine performance and flow field distribution under multiple parameters. It first develops a three-dimensional, multi-parameter, universal geometric model introduces six-region dynamic layering numerical simulation method...

International Journal of Structural Stability and DynamicsAccepted Papers No AccessEnhancing Ride Comfort Reducing Energy Consumption Ultra-High-Speed Elevators Using Deep Reinforcement Learning with Multivariate State Observation Reward MechanismChengxing Yuan, Qing Zhang, Luhui Yang, Donghang Cai, Limin Fan, Dongsheng CongChengxing Zhang Search for more papers by this author , Yanghttps://orcid.org/0000-0001-8652-5438 Cai Fan Cong https://doi.org/10.1142/S0219455426502081Cited by:0...

The ultra-high-speed elevator car–counterweight system will experience substantial aerodynamic effects when operating at high speeds in the annular flow field, particularly moment of intersection. These have a considerable impact on stability elevator's operation. This study utilized unsteady Reynolds-averaged Navier–Stokes approach to investigate characteristics system's entire operation process. three-dimensional transient model is created using dynamic layering mesh technology and then...

Interaction and wear between wheel rail become increasingly serious with the increase in elevator speed load. Uneven roller surface, eccentricity of rollers, looseness brackets result vibration problems high-speed super-high-speed elevators. Therefore, forced differential equation representing guide rails is established based on Bernoulli–Euler theory, shoes car constructed using Darren Bell principle. Then, coupled model rail, shoes, can be obtained relationship force relative displacement...

Long-term energy supplies hinder the application of low-power unmanned ocean devices to deep sea. Ocean wave is a renewable resource with amount stores enormous and high density. The converter (WEC) could be miniaturized so that it can integrated into make up power module. In this paper, small novel heaving point absorber supply for developed based on counter-rotating self-adaptive mechanism. floating body as an important part absorber, geometric parameters optimized increase efficiency...

To effectively suppress the horizontal vibration of high-speed elevator cars caused by uncertainties such as unevenness guide rails and piston wind in shaft, a disturbance observer-based dynamic fuzzy sliding-mode control strategy is proposed, which combination controller an optimal nonlinear observer. First, dynamics model semi-active car system established, external airflow obtained grid technique uneven excitation rail are jointly applied inputs to dynamical model. Then, active...

Marine equipment generally lacks efficient power supply methods. The high energy density of wave can facilitate the converter miniaturization and make them easily integrated into marine equipment. This paper presents a novel point absorber-type converter, which is based on counter-rotating self-adaptable movement mechanism. Comprehensive theoretical analysis, numerical optimization verification experiments were conducted its performance characteristics. It was found that hydrodynamic...

Digital watermarking has been widely used in copyright protection for digital images, but most of the algorithm can't resist print-and-scan process. Print-and-scan attack is a challenging problem watermarks. A against based on PSO (Particle Swarm Optimization) proposed this paper. The watermark information embedded halftone process image screening with phase modulation method. extracted by template, which optimized using algorithm. Both mean filtering and median are to remove noise from...

Visual cryptography is a cryptographic technique which allows visual information to be encrypted in such way that the decryption can performed by human system, without aid of computers. This paper proposes schema hiding within method cryptography. The gray image changed into two halftone images via different dither matrixes respectively, and secret binary pixels are encoded shares. restored stacking shared together. Simulation results show decoded efficiently.

Abstract Low-power, small-size, unoccupied devices are often used in the ocean. However, requirements for long-distance operation and long-term, high-power supplies have always been difficult technical problems to solve. Wave energy can be effectively meet of a high power supply. Based on comprehensive analysis shortcomings existing wave converters, we present an innovative design novel hydraulic flexible mobile system its internal structure. The dynamic model is then simplified into...

Abstract. Due to the defects of internal structure and energy supply carrier, conventional deep sea unoccupied marine equipment cannot meet requirements low power consumption. In this paper, whole a multi-body heave wave conversion system was designed capture convert energy. The consists floating body, an underwater absorber takeoff (PTO). dynamic model mathematical efficiency evaluation were established according analysis. Based on real service environment in South China Sea,...

In traditional Radio Frequency Identification (RFID) reader system, the electromagnetic energy cannot be transferred as much possible, which is caused by discrete resonance frequency of antenna.The distance should reduced this reason.In paper, Direct Digital Synthesizer (DDS) technique and adaptive work mode are applied in RFID reader.Under condition, tag can searched automatically reader.Therefore, error decreased, match between also optimized.As result, reading system expanded.In...

To effectively suppress the horizontal vibration of high-speed elevator car caused by uncertainties such as unevenness guide rails and piston wind in shaft, Disturbance Observer Based Dynamic fuzzy sliding mode control strategy (DOB-DFSMC) is proposed, which a combination dynamic controller (DFSMC) an optimal nonlinear disturbance observer (NDO). First, dynamics model semi-active system established, external airflow obtained grid technique uneven excitation rail are jointly applied inputs to...