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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs
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作者 Lianghao Hua Jianfeng Zhang +1 位作者 Dejie Li Xiaobo Xi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2129-2157,共29页
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej... With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance. 展开更多
关键词 Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm
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Operation Control Method of Relay Protection in Flexible DC Distribution Network Compatible with Distributed Power Supply 被引量:1
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作者 Zihan Qi 《Energy Engineering》 EI 2023年第11期2547-2563,共17页
A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to... A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency. 展开更多
关键词 Compatible distributed power supply FLEXIBILITY DC distribution network relay protection operation control
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Privacy Protection Based Access Control Scheme in Cloud-Based Services 被引量:3
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作者 Kai Fan Qiong Tian +2 位作者 Junxiong Wang Hui Li Yintang Yang 《China Communications》 SCIE CSCD 2017年第1期61-71,共11页
With the rapid development of computer technology, cloud-based services have become a hot topic. They not only provide users with convenience, but also bring many security issues, such as data sharing and privacy issu... With the rapid development of computer technology, cloud-based services have become a hot topic. They not only provide users with convenience, but also bring many security issues, such as data sharing and privacy issue. In this paper, we present an access control system with privilege separation based on privacy protection(PS-ACS). In the PS-ACS scheme, we divide users into private domain(PRD) and public domain(PUD) logically. In PRD, to achieve read access permission and write access permission, we adopt the Key-Aggregate Encryption(KAE) and the Improved Attribute-based Signature(IABS) respectively. In PUD, we construct a new multi-authority ciphertext policy attribute-based encryption(CP-ABE) scheme with efficient decryption to avoid the issues of single point of failure and complicated key distribution, and design an efficient attribute revocation method for it. The analysis and simulation result show that our scheme is feasible and superior to protect users' privacy in cloud-based services. 展开更多
关键词 access control data sharing privacy protection cloud-based services
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High-Speed Trains Automatic Operation with Protection Constraints: A Resilient Nonlinear Gain-based Feedback Control Approach 被引量:2
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作者 Shigen Gao Yuhan Hou +2 位作者 Hairong Dong Sebastian Stichel Bin Ning 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期992-999,共8页
This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of gua... This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed trains.The proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control strategies.Finally,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches. 展开更多
关键词 AUTOMATIC TRAIN operation high-speed TRAIN nonlinear GAIN feedback protection CONSTRAINT resilient control
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Architecture Design for Integrated Wide Area Protection and Control Systems 被引量:2
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作者 Z. Q. Bo Q. P. Wang +3 位作者 Lin Wang Fengqun Zhou Shengming Ge B. M. Zhang 《Journal of Power and Energy Engineering》 2015年第4期412-416,共5页
This paper firstly reviews the recent development in power system protection and control, with special attention paid to the wide-area and integrated protection, in order to look into future development of integration... This paper firstly reviews the recent development in power system protection and control, with special attention paid to the wide-area and integrated protection, in order to look into future development of integration of protection and control for smart grids. This paper mainly reports on the development of integrated wide area protection and control for power systems. The concept of integrated wide area protection and control is introduced, in which a hierarchical protection and control system provides the protection and control of wide area or regional power substations/ plants and their associated power network. The system is mainly divided into three levels, the local, the substation/plant and the wide area/regional protection and control. The integrated functions at each level are described in details with an aim to develop an optimal coordination mechanism between the levels. One of the core elements in the system is the synchronised wide area communication network between the substations and the protection and control system, in which latest communication technology is employed. Another important player in the system is the wide area synchronized protection and control information platform, which not only enables the fusion three line of defence for power system protection and control, but also provides a perfect tool for the application of cloud computing to substations and power networks. 展开更多
关键词 INTEGRATED protection WIDE Area protection protection and control CLOUD COMPUTING
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Seismic protection of frame structures via semi-active control:modeling and implementation issues 被引量:1
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作者 Vincenzo Gattulli Marco Lepidi Francesco Potenza 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第4期627-645,共19页
Theoretical and practical issues concerning the multi-faceted task of mitigating the latero-torsional seismic response of a prototypal frame structure with asymmetric mass distribution are approached, Chevron braces w... Theoretical and practical issues concerning the multi-faceted task of mitigating the latero-torsional seismic response of a prototypal frame structure with asymmetric mass distribution are approached, Chevron braces with embedded magnetorheological dampers acting on the interstory drift are used to ensure additional energy dissipation. The semi-active control strategy employed to govern the modification of the damper characteristics via feedback is based on the selection of optimal forces according to a H2/LQG criterion, with respect to which the actual forces are regulated by a clipped-optimal logic. A dynamic observer is used to estimate the state through a non-collocated placement of the acceleration sensors. Several aspects to be addressed throughout the complex process including the design, modelization, and implementation phases of semi-active protection systems are discussed. Finally, experimental results obtained to mitigate the motion induced by ground excitation in a large-scale laboratory prototype, simulating the seismic response of a two-story building, are summarized. 展开更多
关键词 seismic protection flame structures semi-active control magnetorheological damper
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Protection and Quality Control of Wild Chinese Herbal Medicine Resources in Nature Reserves by Taking Longyuwan Scenic Spot Within Funiu Mountain Nature Reserve as an Example 被引量:1
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作者 Wang Shao-hui Liu Meng-na +4 位作者 Wang Xu Zhang Ya-chen Han Yi-wen Zhang Ce Liu Tong-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期90-96,共7页
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr... This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves. 展开更多
关键词 nature reserve wild Chinese herbal medicine resource protection quality control
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Multi-Variable Flocking Control for Multi-Agent Systems via a Received Signal Strength Indicator 被引量:1
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作者 Xin-Ping Guan Shao-Min Xing Xiao-Yuan Luo 《Journal of Electronic Science and Technology》 CAS 2011年第3期231-238,共8页
A novel flocking control approach is proposed for multi-agent systems by integrating the variables of velocities, motion directions, and positions of agents. A received signal strength indicator (RSSI) is applied as... A novel flocking control approach is proposed for multi-agent systems by integrating the variables of velocities, motion directions, and positions of agents. A received signal strength indicator (RSSI) is applied as a variable to estimate the inter-distance between agents. A key parameter that contains the local information of agents is defined, and a multi-variable controller is proposed based on the parameter. For the position control of agents, the RSSI is introduced to substitute the distance as a control variable in the systems. The advantages of RSSI include that the relative distance between every two agents can be adjusted through the communication quality under different environments, and it can shun the shortage of the limit of sensors. Simulation studies demonstrate the effectiveness of the proposed control approach. 展开更多
关键词 Index Terms---Flocking multi-agent system multi-variable control received signal strength indicator.
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Immobilization of antibodies on the self-assembled monolayer by antigen-binding site protection and immobilization kinetic control 被引量:1
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作者 Myungok Yoon Hyun Jin Hwang Jeong Hee Kim 《Journal of Biomedical Science and Engineering》 2011年第4期242-247,共6页
The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-bind... The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-binding site of the antibody prior to immo-bilization to -functionalized mixed self-assembled monolayer (SAM) of 12-mercaptododecanoic acid and 1-heptanethiol. More importantly, the number of immobilization bonds formed between each an-tigen-binding site protected antibody molecule and the solid surface was controlled by optimizing the mole fraction of the activated carboxyl group of the linker molecules in the mixed SAM. The amount of antibody used in this study was approximately equivalent to the amount for one monolayer surface coverage. The resulting activity of protected immo-bilized antibody was about 10 fold higher than that of random immobilized 展开更多
关键词 Antibody Oriented IMMOBILIZATION Antigen-Binding Site protection SELF-ASSEMBLED MONOLAYER Kinetic control
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Study on DeviceNet communication mechanism and its application in protection measurement and control system 被引量:1
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作者 佟为明 Li Zhongwei +1 位作者 Sun Fanjin Cheng Shukang 《High Technology Letters》 EI CAS 2007年第1期1-5,共5页
To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is ... To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability. 展开更多
关键词 communication mechanism protection measurement and control system FIELDBUS DEVICENET
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The Research and Application of Prediction Control in Multi-variable Control Process
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作者 WEI Shuangying School of Management,Wuhan University of Technology,Wuhan 430070,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期850-857,共8页
The modern industrial control objects become more and more complicated,and higher control quality is required, so a series of new control strategies appear,applied,modified and develop quickly.This paper researches a ... The modern industrial control objects become more and more complicated,and higher control quality is required, so a series of new control strategies appear,applied,modified and develop quickly.This paper researches a new control strategy- prediction control-and its application in Multi-Variable Control Process.The research result is worthy for automatic control in pro- cess industry. 展开更多
关键词 prediction control ROLLED optimization FEEDBACK CALIBRATION multi-variable control SYSTEM IDENTIFY SYSTEM control
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Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases
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作者 Mo-Wei Kong Yang Yu +2 位作者 Ying Wan Yu Gao Chun-Xiang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第36期4036-4043,共8页
This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associat... This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases. 展开更多
关键词 Glucagon-like peptide-1 receptor agonists Glycemic control Multisystem diseases Mechanism of action Cardiovascular protection Renal disease Bone metabolism Non-alcoholic fatty liver disease NEUROprotection Polycystic ovary syndrome
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Research on Technology of Electromagnetic Protection for the Generator Control System
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作者 Baocheng Wang Guyong Han Lin Zhu 《Journal of Power and Energy Engineering》 2014年第4期7-12,共6页
Generator control system decides whether the generator can work as usual or not, as well as its stability of performance. Both types of generators control system composed of the transistor and DSP are sensitive to out... Generator control system decides whether the generator can work as usual or not, as well as its stability of performance. Both types of generators control system composed of the transistor and DSP are sensitive to outward electromagnetic interference, directly related to the generator performance. In this text, we first analyze the electromagnetic interference threat generator control system of transistor type may face, then design a electromagnetic protection plan for the intake, the panel and the sense organ. This work is of great significance in improving its electromagnetic protection ability and stability of performance. 展开更多
关键词 GENERATOR control System ELECTROMAGNETIC INTERFERENCE DAMAGE Analysis ELECTROMAGNETIC protection Design
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Regional Coordinated Development and Joint Prevention and Control for Environmental Protection in China in the New Era
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作者 Wenqi YUE Sheng WANG +2 位作者 Nan SHAO Yuqing LIU Yiran ZOU 《Meteorological and Environmental Research》 CAS 2021年第4期17-20,共4页
The three important historical development stages of China from"standing up","getting rich"to"becoming strong"were analyzed deeply.Regional coordinated development policies and strategies... The three important historical development stages of China from"standing up","getting rich"to"becoming strong"were analyzed deeply.Regional coordinated development policies and strategies have also gone through the"enlightenment stage","development stage"and"mature stage".On this basis,the problems of the coordination of China s regional coordinated development and joint prevention and control for environmental protection in the new era,as well as suggestions for the next step were further analyzed. 展开更多
关键词 Regional coordinated development Joint prevention and control Environmental protection
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The Application of Three-Dimensional Integrated Protection Technology in High Slope Control of Mountainous Highway
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作者 Jun Han 《Frontiers Research of Architecture and Engineering》 2018年第1期1-3,共3页
In the process of China's national economy construction,the role of highway traffic is unquestionable.And with the continuous development of society and the continuous improvement of highway grade,the work of the ... In the process of China's national economy construction,the role of highway traffic is unquestionable.And with the continuous development of society and the continuous improvement of highway grade,the work of the highway slope governance become a top priority,especially for some mountainous area highway,strengthen management of slope is very critical.The emergence of three-dimensional comprehensive protection technology has created great convenience for the management of the slope of the mountainous highway,and the safety of the mountain highway has been improved effectively.In view of this,the paper focuses on the application of three-dimensional integrated protection technology in the treatment of highway high slope in mountainous areas for reference and reference. 展开更多
关键词 STEREO synthesis protection technology MOUNTAIN ROADS SLOPE control Apply
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Advancement in Wide Area Monitoring Protection and Control Using PMU’s Model in MATLAB/SIMULINK
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作者 Waheed Ur Rahman Muhammad Ali +7 位作者 Amjad Ullah Hafeez Ur Rahman Majid Iqbal Haseeb Ahmad Adnan Zeb Zeeshan Ali M. Ahsan Shahzad Beenish Taj 《Smart Grid and Renewable Energy》 2012年第4期294-307,共14页
A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power system... A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station. 展开更多
关键词 WIDE Area MONITORING protection and control (WAMPAC) Phasor Measurement uNit (PMU) WIDE Area MONITORING (WAM) Global Positioning System (GPS) WIDE Area controlLER (WAC) Local Area controlLER (LAC) Phase Angle MONITORING (PAM) Automatic Generation control (AGC) Circuit Breaker (CB) Current TRANSFORMERS (CTs) Potential TRANSFORMERS (PTs)
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Research on System Architecture of Novel Universal Integrated Control and Protection Platform for Converter Stations 被引量:1
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作者 HU Jing ZHAO Chengyong +3 位作者 ZHAO Guoliang ZHOU Fei WANG Jing CAI Xinhong 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0018-I0018,共1页
关键词 保护系统 集成控制 高压直流输电工程 换流站 架构 平台 通用 HVDC
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Discussion on the Prevention and Control Countermeasures of Sudden Disasters on Protected Vegetable in Hebei Province 被引量:1
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作者 刘云 梁玉芹 +1 位作者 王灵敏 宋炳彦 《Agricultural Science & Technology》 CAS 2016年第3期511-515,共5页
Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While... Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While protected vegetables often encountered sudden disasters in production and were restricted with the conditions of low temperature and weak light. Aimed at the sudden disasters of protected vegetable production in Hebei Province,the countermeasures for disaster prevention and control were put forward from the aspects of variety selection, seedling treatment technology,grafting technique,cultivation and management,flower and fruit retention technology,application of exogenous substance,rational fertilization,transgenic technology and so on,in order to reduce production risks and cut loss,realize that protected vegetable production is safe,good-quality and efficient. 展开更多
关键词 Hebei Province protected vegetable Sudden disasters Prevention and control countermeasures
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Validating the CorrectWearing of Protection Mask by Taking a Selfie:Design of a Mobile Application“CheckYourMask”to Limit the Spread of COVID-19 被引量:2
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作者 Karim Hammoudi Adnane Cabani +1 位作者 Halim Benhabiles Mahmoud Melkemi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期1049-1059,共11页
In a context of a virus that is transmissive by sputtering,wearing masks appear necessary to protect the wearer and to limit the propagation of the disease.Currently,we are facing the 2019-2020 coronavirus pandemic.Co... In a context of a virus that is transmissive by sputtering,wearing masks appear necessary to protect the wearer and to limit the propagation of the disease.Currently,we are facing the 2019-2020 coronavirus pandemic.Coronavirus disease 2019(COVID-19)is an infectious disease with first symptoms similar to the flu.The symptom of COVID-19 was reported first in China and very quickly spreads to the rest of the world.The COVID-19 contagiousness is known to be high by comparison with the flu.In this paper,we propose a design of a mobile application for permitting everyone having a smartphone and being able to take a picture to verify that his/her protection mask is correctly positioned on his/her face.Such application can be particularly useful for people using face protection mask for the first time and notably for children and old people.The designed method exploits Haar-like feature descriptors to detect key features of the face and a decision-making algorithm is applied.Experimental results show the potential of this method in the validation of the correct mask wearing.To the best of our knowledge,our work is the only one that currently proposes a mobile application design“CheckYourMask”for validating the correct wearing of protection mask. 展开更多
关键词 Face protection masks public health support health education COVID-19 CORONAVIRUS E-HEALTH m-health mobile health public health system epidemic prevention and control
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Experimental research on methane control of mining upper protective layers 被引量:2
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作者 Luo Yong 《Engineering Sciences》 EI 2009年第3期41-46,共6页
In order to solve coal and gas outbursts during mining coal seam,studying on related problems were carried out. According to the theories of mining upper protective layer,proper mining plan were designed and performed... In order to solve coal and gas outbursts during mining coal seam,studying on related problems were carried out. According to the theories of mining upper protective layer,proper mining plan were designed and performed through field experiment. By means of examining several parameters obtained from the field experiment,the protective effects were evaluated and the protective scope and related parameters were determined. The results of field experiment show that the danger of outbursts was evidently eliminated and the method of mining protective layers is effective and the safety and economic benefits are remarkable. The research has really applied worth and will give beneficial references to mining area with analogous conditions. 展开更多
关键词 methane control protective layer coal and gas outburst field experiment
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