scholarly journals Control Method of Slipstream Gas Source System of a Propeller

2019 ◽  
Vol 267 ◽  
pp. 01001
Author(s):  
Jinchun Shi
Keyword(s):  
Control Method ◽  
Low Flow ◽  
Source Control ◽  
Whole Process ◽  
Gas Source ◽  
Compressed Gas ◽  
Flow Through ◽  
Great Energy ◽  
Large Flow ◽  
Stable Control

For the slipstream gas source control system of propeller, there is no mature application in China. The traditional slipstream gas source system manually realizes the stable control of gas and flow through the self-operated pressure reducing device. But this mode can only be used in the condition of small pressure and low flow, cannot meet the actual need of high pressure and large flow, and cannot monitor and automatically control the energy consumption of compressed gas and heating equipment, resulting in great energy waste. Based on the actual engineering conditions, and according to the characteristics, user requirements and work flow of the slipstream gas source system, this paper describes a new control method for the slipstream gas source system of a propeller in detail, which solves the issue of automatic control in the whole process and realizes the key technical point, rapid stabilizing of airflow pressure and temperature.

Simulation on Linear-Motor-Driven Water Hydraulic Reciprocating Plunger Pump

2013 ◽  
Vol 842 ◽  
pp. 530-535 ◽  
Author(s):  
Zeng Meng Zhang ◽  
Yong Jun Gong ◽  
Jiao Yi Hou ◽  
Han Peng Wu
Keyword(s):  
Flow Rate ◽  
Deep Sea ◽  
High Efficiency ◽  
Control Method ◽  
Sea Water ◽  
Linear Motor ◽  
Low Flow ◽  
Flow Pulsation ◽  
Plunger Pump ◽  
Water Hydraulic

The water hydraulic reciprocating plunger pump driven by linear motor is suitable to deep sea application with high efficiency and variable control. Aiming to study the principle structure and working characteristics of the pump, two patterns of valve and piston distribution were designed. And the control method and the performance were analyzed by simulation based on the AMESim model. The results show that the pressure and flow pulsation of piston type pump are much smaller than the valve type, even though the piston type is large in scale and works at low flow rate. Compared with a valve distribution tri-linear-motor reciprocating plunger pump (VDTLMP), as the flow rate of the piston distribution double linear motor reciprocating plunger pump (PDDLMP) is decreased from 36.7 L/min to 21.2 L/min theoretically, the pressure pulsation amplitude is decreased from 46% to 2%, and the flow pulsation rate is also decreased from 0.266 to 0.007. These results contribute to the research on deep-sea water hydraulic power pack and direct drive pump with high efficiency and energy conservation.

Calculation of flow of a viscous compressed Gas in the casing of low-flow centrifugal Compressor stages

1998 ◽  
Vol 34 (11) ◽  
pp. 672-676
Author(s):  
A. I. Evtushenko ◽  
A. K. Gaponov ◽  
I. M. Notkina ◽  
K. P. Seleznev
Keyword(s):  
Centrifugal Compressor ◽  
Low Flow ◽  
Compressed Gas

The Investigation of the Optimization Scheme of the Low-cycle Fatigue Cropping Based on the Acoustic Emission Technique

2021 ◽  
Author(s):  
Yujian Ren ◽  
Jingxiang Li ◽  
Yuanzhe Dong ◽  
Dong Jin ◽  
Shengdun Zhao
Keyword(s):  
Acoustic Emission ◽  
High Frequency ◽  
Control Method ◽  
Low Cycle Fatigue ◽  
Control Strategies ◽  
Low Frequency ◽  
Loading Frequency ◽  
Cycle Fatigue ◽  
Al 6061 ◽  
Whole Process

Abstract High efficiency and good section quality are two main objectives of metal bar cropping. A suitable control method can help to achieve both goals. An investigation of the control method of low-cycle fatigue cropping (LCFC) based on the acoustic emission (AE) technique has been proposed in this study. Ring-down counts and kurtosis are used to monitor the whole process of LCFC. The results showed that kurtosis is more suitable for monitoring the LCFC process and as a critical parameter to optimize the control method than ring-down counts in the noisy factory environment.Moreover, three types of materials are studied in this experiment; by combine with the AE results, macroscopic images and microscopic images of sections, characteristics of various LCFC stages are obtained. The results also indicated reduce the area of the transient fracture zone is the key to improve the section quality. Reducing the load frequency before the unstable crack propagation stage will beneficial to realize the goals. Based on the evaluation of kurtosis, an optimized control method is presented, and two control parameters: transient time T and the critical value of the slope of kurtosis C are determined. For 16Mn, 1045 and Al 6061, the T is 5s, 10s, and 1s, respectively. For 16Mn, 1045, and Al 6061, the C is 100, 300, and 0, respectively. Two parameters, h and S, are used to evaluate the section quality and four control strategies are compared. The results indicate the optimal control methods can improve the section quality effectively. The influence trend of reducing loading frequency is investigated by further comparison. It can be seen as the frequency decreases, the efficiency of the section quality improving decreases. In order to realize the optimal results, different control strategies are adopted for different materials. Strategy 1 (high frequency is 20Hz，high frequency thought the whole process), strategy 2 (high frequency is 20Hz，low frequency is 8.33Hz), and strategy 3 (high frequency is 20Hz，low frequency is 6.67Hz) is suitable for Al 6061, 1045, and 16Mn, respectively.

scholarly journals Deep Reinforcement Learning Based Left-Turn Connected and Automated Vehicle Control at Signalized Intersection in Vehicle-to-Infrastructure Environment

Information ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 77 ◽  
Author(s):  
Juan Chen ◽  
Zhengxuan Xue ◽  
Daiqian Fan
Keyword(s):  
Reinforcement Learning ◽  
Control Method ◽  
Signalized Intersection ◽  
Signal Control ◽  
Left Turn ◽  
Automated Vehicle ◽  
Whole Process ◽  
Policy Gradient ◽  
Experience Replay ◽  
Automated Vehicle Control

In order to solve the problem of vehicle delay caused by stops at signalized intersections, a micro-control method of a left-turning connected and automated vehicle (CAV) based on an improved deep deterministic policy gradient (DDPG) is designed in this paper. In this paper, the micro-control of the whole process of a left-turn vehicle approaching, entering, and leaving a signalized intersection is considered. In addition, in order to solve the problems of low sampling efficiency and overestimation of the critic network of the DDPG algorithm, a positive and negative reward experience replay buffer sampling mechanism and multi-critic network structure are adopted in the DDPG algorithm in this paper. Finally, the effectiveness of the signal control method, six DDPG-based methods (DDPG, PNRERB-1C-DDPG, PNRERB-3C-DDPG, PNRERB-5C-DDPG, PNRERB-5CNG-DDPG, and PNRERB-7C-DDPG), and four DQN-based methods (DQN, Dueling DQN, Double DQN, and Prioritized Replay DQN) are verified under 0.2, 0.5, and 0.7 saturation degrees of left-turning vehicles at a signalized intersection within a VISSIM simulation environment. The results show that the proposed deep reinforcement learning method can get a number of stops benefits ranging from 5% to 94%, stop time benefits ranging from 1% to 99%, and delay benefits ranging from −17% to 93%, respectively compared with the traditional signal control method.

scholarly journals Oxygen devices and delivery systems

Breathe ◽  
2019 ◽  
Vol 15 (3) ◽  
pp. e108-e116
Author(s):  
Georgia Hardavella ◽  
Ioannis Karampinis ◽  
Armin Frille ◽  
Katherina Sreter ◽  
Ilona Rousalova
Keyword(s):  
Delivery Systems ◽  
Low Flow ◽  
Liquid Oxygen ◽  
Team Members ◽  
Advantages And Disadvantages ◽  
Compressed Gas ◽  
Chronic Pulmonary Diseases ◽  
Outpatient Settings ◽  
Gas Cylinders ◽  
Selection Of

Oxygen use has extended from inpatient to outpatient settings for patients with chronic pulmonary diseases and complications of hypoxaemia. This article presents an overview of oxygen devices (oxygen concentrators, compressed gas cylinders and liquid oxygen) and delivery systems (high- and low-flow). The indications, advantages and disadvantages of each device and delivery system are presented, aiming to offer updated knowledge to the multidisciplinary team members managing patients with respiratory failure, and therefore allowing appropriate selection of devices and delivery systems that are tailored to the needs of each patient.

Study on FAIMS ion source control and optimization using over-electric field

2020 ◽  
Vol 34 (12) ◽  
pp. 2050127
Author(s):  
Lunchao Zhong ◽  
Tao Gong ◽  
Hui Ma ◽  
Wenyan Shi ◽  
Peirong Wang ◽  
...  
Keyword(s):  
Electric Field ◽  
Flow Rate ◽  
Clinical Medicine ◽  
Environmental Pollutants ◽  
Ion Source ◽  
Low Flow ◽  
Source Control ◽  
Toxic Substances ◽  
Long Distance ◽  
Core Technology

Ion source provides sample ions for FAIMS. The key technology is ionization method. Efficient ionization of analytes is the core technology for data acquisition in high quality FAIMS systems. In order to long-distance detect and analyze harmful and toxic substances such as explosives, drugs, chemical reagents and environmental pollutants in an open environment, without pretreatment, real-time and on-line, the ion source control and its technical device using excessive electric field were designed and developed. The disadvantages of high flow rate of APCI and low flow rate of ESI are integrated, based on the chemical analysis principle of FAIMS, an experimental platform of ionization technology based on excessive electric field is proposed and designed, which mainly includes: ion focusing system, flat-panel migration zone with focusing structure, sample integration, etc. The experimental results show that the ion source based on excessive electric field can be widely used in biochemical weapon warning, drug tablet detection, environmental monitoring, food and drug detection and clinical medicine, and the detection limit can reach 0.1 ppm.

Nonlinear Lyapunov-Based Stable Control Method of the Single-Phase Shunt Active Power Filter

2011 ◽  
Vol 354-355 ◽  
pp. 1390-1393 ◽  
Author(s):  
Lan Fang Li ◽  
Hong Geng Yang ◽  
Wei Ming Guo ◽  
Ya Mei Liu ◽  
Fang Wei Xu ◽  
...  
Keyword(s):  
Lyapunov Function ◽  
Single Phase ◽  
Control Method ◽  
Active Power Filter ◽  
Active Power ◽  
Shunt Active Power Filter ◽  
Correct Operation ◽  
Power Filter ◽  
Control Output ◽  
Stable Control

This paper proposes a nonlinear Lyapunov-based control method of the single-phase shunt active power filter (APF). The system is modeled firstly and then the compensated current of the APF is calculated. The energetic like Lyapunov function is constructed and the control output is determined through ensuring the differential of the Lyapunov function negative, which grantee the convergence of the APF system. Considering that the time-varying load may cause greater fluctuations in DC voltage, an average value is used to calculate the control output. A globally stable control is possible and it is insensitive to the parameter uncertainties and robustness to the disturbances. Simulation results are obtained using Matlab/ Simulink. These results verify the correct operation of the proposed control method.

scholarly journals Modeling nutrient consumptions in large flow-through bioreactors for tissue engineering

2009 ◽  
Vol 103 (5) ◽  
pp. 1003-1015 ◽  
Author(s):  
Mamatha Devarapalli ◽  
Benjamin J. Lawrence ◽  
Sundararajan V. Madihally
Keyword(s):  
Tissue Engineering ◽  
Flow Through ◽  
Large Flow

Approximate Finite-Time Stable Control for Simple Interconnected Power Systems

2013 ◽  
Vol 846-847 ◽  
pp. 305-308
Author(s):  
Jian Li Zhao ◽  
Bao Feng Yan ◽  
Bo Chen
Keyword(s):  
Power Systems ◽  
Finite Time ◽  
Control Method ◽  
Nonlinear Feedback Control ◽  
Nonlinear Feedback ◽  
Extended State ◽  
Interconnected Power Systems ◽  
Feedback Control Method ◽  
Simulation Results ◽  
Stable Control

Considering the simple interconnected power systems, the finite-time stable control problem is studied. A nonlinear feedback control method with dynamic active compensation is proposed, which makes the systems achieves approximately the finite-time stable control. Meantime, in order to solve the problem of system uncertainty and unmeasurable states, an extended state observer is designed. Simulation results show the effectiveness of the control method.

Study on Force Control in Abrasive Polishing of Aspheric Parts

2010 ◽  
Vol 37-38 ◽  
pp. 1287-1291 ◽  
Author(s):  
Di Zheng ◽  
Bi Da Lv ◽  
Jian Ming Zhan ◽  
Li Yong Hu
Keyword(s):  
Machine Tools ◽  
Control Method ◽  
Cnc Machine Tools ◽  
Cnc Machine ◽  
Polishing Force ◽  
Application Fields ◽  
Polishing Tool ◽  
The Mathematical Model ◽  
Precision Machines ◽  
Stable Control

Aspheric parts are attracting many researchers’ attention for their excellent optical properties. The commonly used manufacturing technology for aspheric parts are mainly based on dedicated high precision machines, resulting in high cost and restricted application fields. To polish this kind of parts on general CNC machine tools, however, the surface quality improvement is limited due to the problem of force-position coupling. In order to solve this issue, a force-position decoupling control method for abrasive polishing was studied, a corresponding comliant polishing tool system was developed, and the mathematical model of the tool system was established. In addition, a polishing force controller was designed, and the performance of the tool system was numerically simulated. Simulation results showed that the polishing tool system can effectively achieve the tasks of force-position decoupling and the stable control of the polishing force.

Sign in / Sign up

Export Citation Format

Share Document