An Integrated Hydrodynamics and Control Model of A Tethered Underwater Robot

Abstract The trajectory of tethered underwater robot is usually controlled by actuating the rotating speeds of control propellers attached to the robot and/or adjusting the length of umbilical cable. When the trajectory control problem of a tethered underwater robot is studied, it is necessary to couple the main body of underwater robot, umbilical cable and control propellers together forming an integrated hydrodynamic model so that the robot is in a comprehensive dynamic equilibrium condition, suitable control algorithms are then jointed into the hydrodynamic model constructing a hydrodynamic and control model for the tethered underwater robot system. Only in this way the hydrodynamic and control nature of a tethered underwater robot during different kinds of control manipulations can be numerically revealed objectively. In this paper, a hydrodynamic and control model to simulate the trajectory following control of a tethered underwater robot system is proposed, and the hydrodynamic performances of the robot and the umbilical cable are observed. To achieve this goal, three-dimensional hydrodynamic model of tethered underwater robot system is first introduced, feed-forward control technique for adjusting the length of umbilical cable and incremental PID algorithm for regulating the rotating speeds of propellers are then incorporated into the hydrodynamic model forming the hydrodynamic and control model. Based on the established hydrodynamic and control mode, relationships between the thrusts from the propellers and the rotating speeds of the propellers, and those among the trajectory following of the underwater robot and the control actions of adjusting the length of umbilical cable and governing the rotating speeds of the propellers are analyzed, and also the hydrodynamic performances of the tethered underwater robot system under the control manipulation are observed. In the research, the amplitude limit filtering method is applied in solving the governing equations of the umbilical cable, this technique is applied to avoid the chattering effect in the cable tension computation, so that a successive and stable computation process is maintained. The main factors affecting the singular nature of coefficient matrices during the numerical solutions of the proposed model are also investigated in the paper.

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Protection and Response of a Tertiary Hospital in Shenzhen, China to the COVID-19 Outbreak—the Practice of the Comprehensive Response Mode

Disaster Medicine and Public Health Preparedness ◽

10.1017/dmp.2021.218 ◽

2021 ◽

pp. 1-17

Author(s):

Benling Hu ◽

Le Yang ◽

Chan Wei ◽

Min Luo

Keyword(s):

Prevention And Control ◽

Tertiary Hospital ◽

Control Model ◽

Normal Operation ◽

Process Reengineering ◽

Equipment Management ◽

Hospital Acquired Infection ◽

Public Health Emergencies ◽

Hospital Acquired ◽

And Control

ABSTRACT Objective: To evaluate the management mode for the prevention and control of coronavirus 2019 (COVID-19) transmission utilized at a general hospital in Shenzhen, China, with the aim to maintain the normal operation of the hospital. Methods: From January 2, 2020 to April 23, 2020, Hong Kong–Shenzhen Hospital, a tertiary hospital in Shenzhen, has operated a special response protocol named comprehensive pandemic prevention and control model, which mainly includes six aspects: 1) human resource management; 2) equipment management; 3) logistics management; 4) cleaning, disinfection and process reengineering; 5) environment layout; 6) and training and assessment. The detail of every aspect was described and its efficiency was evaluated. Results: A total of 198,802 patients were received. Of those, 10,821 were hospitalized; 26,767 were received by the emergency department and fever clinics; 288 patients were admitted for observation with fever; and 324 were admitted as suspected cases for isolation. Under the protocol of comprehensive pandemic prevention and control model, no case of hospital-acquired infection with COVID-19 occurred among the inpatients or staff. Conclusion: The present comprehensive response model may be useful in large public health emergencies to ensure appropriate management and protect the health and life of individuals.

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A literature review and cluster analysis of the Aachen production planning and control model under Industry 4.0

Procedia Computer Science ◽

10.1016/j.procs.2021.01.158 ◽

2021 ◽

Vol 180 ◽

pp. 208-218

Author(s):

Jan-Phillip Herrmann ◽

Sven Tackenberg ◽

Elio Padoano ◽

Thilo Gamber

Keyword(s):

Cluster Analysis ◽

Literature Review ◽

Production Planning ◽

Industry 4.0 ◽

Control Model ◽

Production Planning And Control ◽

Planning And Control ◽

And Cluster Analysis ◽

And Control

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Intelligent Management and Control Model of Secret Carriers Based on Context-aware

2020 IEEE 9th Joint International Information Technology and Artificial Intelligence Conference (ITAIC) ◽

10.1109/itaic49862.2020.9338842 ◽

2020 ◽

Author(s):

Hongshan Kong ◽

Jun Tang ◽

Bin Yu

Keyword(s):

Control Model ◽

Context Aware ◽

Intelligent Management ◽

And Control

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Power Reserve Classification and Control for Peaking Balance with Intermittent Generation Grid

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.521.252 ◽

2014 ◽

Vol 521 ◽

pp. 252-255

Author(s):

Jian Yuan Xu ◽

Jia Jue Li ◽

Jie Jun Zhang ◽

Yu Zhu

Keyword(s):

Real Time ◽

Balance Control ◽

Control Model ◽

Intermediate Variable ◽

Proposed Model ◽

Grid Operators ◽

Period Constant ◽

Grid Operation ◽

And Control ◽

Time Reserve

The problem of intermittent generation peaking is highly concerned by the grid operator. To build control model for solving unbalance of peaking is great necessary. In this paper, we propose reserve classification control model which contain constant reserve control model with real-time reserve control model to guide the peaking balance of the grid with intermittent generation. The proposed model associate time-period constant reserve control model with real-time reserve control model to calculate, and use the peaking margin as intermediate variable. Therefore, the model solutions which are the capacity of reserve classification are obtained. The grid operators use the solution to achieve the peaking balance control. The proposed model was examined by real grid operation case, and the results of the case demonstrate the validity of the proposed model.

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