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Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China
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作者 WANG Jing WEI Yulu +2 位作者 PENG Biao LIU Siqi LI Jianfeng 《Journal of Arid Land》 SCIE CSCD 2024年第1期131-145,共15页
Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implicatio... Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security. 展开更多
关键词 ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model Loess Plateau
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Analysis of thermal management and anti-mechanical abuse of multi-functional battery modules based on magneto-sensitive shear thickening fluid
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作者 Yang XIONG Bo LU +1 位作者 Yicheng SONG Junqian ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期529-542,共14页
Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cann... Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design. 展开更多
关键词 magneto-sensitive shear thickening fluid(MSTF) battery module impact protection temperature control integrated design
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view
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作者 Wei Wang Jiaqi Liu +2 位作者 Shiyao Lin Baokui Geng Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期211-221,共11页
In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated... In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets. 展开更多
关键词 Integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer
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A Fine-grained Building Height Control Method for Heritage Areas from the Perspective of Visual Integrity
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作者 WANG Xi HOU Miaole CHEN Fan 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期66-79,共14页
This study proposes a refined methodology for controlling building heights in heritage areas.In order to protect the visual integrity of the heritage area,buildings should not obstruct the view from important site poi... This study proposes a refined methodology for controlling building heights in heritage areas.In order to protect the visual integrity of the heritage area,buildings should not obstruct the view from important site points and viewpoints to the periphery.By calculating the building height thresholds that buildings should not obscure the view from each viewpoint,the results of which are weighted and superimposed,and the values are extracted to each building unit as a refined building height control guideline.This study takes the Zhoukoudian area as a case study,applies the refined building height control criterion to the Zhoukoudian Site,and relies on this refined criterion to assess the visual integrity of the Zhoukoudian area,so as to realize the scientific planning and monitoring of the Zhoukoudian area.The refined building height control method can be applied to building height planning and visual landscape protection in large heritage areas. 展开更多
关键词 building height control visual integrity assessment observation points
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Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure
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作者 Elham Aghabarari Fereidoun Amini Pedram Ghaderi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期227-240,共14页
The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible ... The combination of structural health monitoring and vibration control is of great importance to provide components of smart structures.While synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive control.In this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are integrated.First,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MFRLS)method.Then,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be operational.Optimization is also performed based on the probability density function of the energy under the seismic excitation at any time.Finally,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed approach.The simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems. 展开更多
关键词 integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm
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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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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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DNA Barcoding of Insects and Its Direct Application for Plant Protection
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作者 Peter Quandahor Iddrisu Yahaya +11 位作者 Francis Kusi Issah Sugri Julius Yirzagla Abdul Karim Alhassan Jerry A. Nboyine George Y. Mahama Godwin Opoku Mohammed Mujitaba Dawuda Asieku Yahaya Theophilus Kwabla Tengey Rofela Combey John Abraham 《Open Journal of Applied Sciences》 2024年第3期676-686,共11页
The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strateg... The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity and profitability are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on synthetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability to correctly identify pest and beneficial organisms. This is due to some natural traits such as phenology or pesticide susceptibility browbeaten by IPM strategies to avert pest establishment. Specifically, Deoxyribonucleic acid (DNA) sequence information was applied effectively for the identification of some micro-organisms. This technology, DNA barcoding, allows for the identification of insect species by using short, standardized gene sequences. DNA barcoding is basically based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection. 展开更多
关键词 DNA Barcoding Integrated Pest Management TAXONOMY BIOSECURITY Crop protection
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Solvability and Construction of a Solution to the Fredholm Integral Equation of the First Kind
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作者 Aisagaliev Serikbai Nurmagambetov Dias Sevryugin Ilya 《Journal of Applied Mathematics and Physics》 2024年第2期720-735,共16页
The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert spa... The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert space. Necessary and sufficient conditions for the existence of a solution are obtained. A method of constructing a solution of the Fredholm integral equation of the first kind is developed. A constructive theory of solvability and construction of a solution to a boundary value problem of a linear integrodifferential equation with a distributed delay in control, generated by the Fredholm integral equation of the first kind, has been created. 展开更多
关键词 Integral Equations SOLVABILITY Solution Construction controlLABILITY Minimizing Sequences
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Reliability analysis for vertical integration of protection,measurement,merge unit,and intelligent terminal device 被引量:1
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作者 Ying Li Weiquan Wang +3 位作者 Liang Zhang Zhujian Liang Zhenli Xu Yuansheng Liang 《Global Energy Interconnection》 EI CSCD 2023年第6期772-784,共13页
The reliability analysis of vertically integrated protection devices is crucial for designing International Electrotechnical Commission(IEC)61850-based substations.This paper presents the hardware architecture of a fo... The reliability analysis of vertically integrated protection devices is crucial for designing International Electrotechnical Commission(IEC)61850-based substations.This paper presents the hardware architecture of a four-inone vertically integrated device and the information transmission path of each function based on the functional information transmission chain of protection devices,measurement and control devices,merging units,and intelligent terminals.Additionally,a reliability analysis model of the protection device and its protection system is constructed using the fault tree analysis method while considering the characteristics of each module of the vertically integrated device.The stability probability of the protection system in each state is analyzed by combining the state-transfer equations of line and busbar protection with a Markov chain.Finally,the failure rate and availability of the protection device and its protection system are calculated under different ambient temperatures using a 110 kV intelligent substation as an example.The sensitivity of each device module is analyzed. 展开更多
关键词 Vertical integration of secondary system device Reliability of secondary system IEC 61850-based substation Relay protection
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Beyond 5G Networks: Integration of Communication, Computing, Caching, and Control 被引量:2
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作者 Musbahu Mohammed Adam Liqiang Zhao +1 位作者 Kezhi Wang Zhu Han 《China Communications》 SCIE CSCD 2023年第7期137-174,共38页
In recent years,the exponential proliferation of smart devices with their intelligent applications poses severe challenges on conventional cellular networks.Such challenges can be potentially overcome by integrating c... In recent years,the exponential proliferation of smart devices with their intelligent applications poses severe challenges on conventional cellular networks.Such challenges can be potentially overcome by integrating communication,computing,caching,and control(i4C)technologies.In this survey,we first give a snapshot of different aspects of the i4C,comprising background,motivation,leading technological enablers,potential applications,and use cases.Next,we describe different models of communication,computing,caching,and control(4C)to lay the foundation of the integration approach.We review current stateof-the-art research efforts related to the i4C,focusing on recent trends of both conventional and artificial intelligence(AI)-based integration approaches.We also highlight the need for intelligence in resources integration.Then,we discuss the integration of sensing and communication(ISAC)and classify the integration approaches into various classes.Finally,we propose open challenges and present future research directions for beyond 5G networks,such as 6G. 展开更多
关键词 4C 6G integration of communication computing caching and control i4C multi-access edge computing(MEC)
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Proportion Integration Differentiation(PID)Control Strategy of Belt Sander Based on Fuzzy Algorithm
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作者 陈坤 张亚伟 +1 位作者 张振 桂志伟 《Journal of Donghua University(English Edition)》 CAS 2023年第2期177-184,共8页
Aiming at solving the problems of response lag and lack of precision and stability in constant grinding force control of industrial robot belts,a constant force control strategy combining fuzzy control and proportion ... Aiming at solving the problems of response lag and lack of precision and stability in constant grinding force control of industrial robot belts,a constant force control strategy combining fuzzy control and proportion integration differentiation(PID)was proposed by analyzing the signal transmission process and the dynamic characteristics of the grinding mechanism.The simulation results showed that compared with the classical PID control strategy,the system adjustment time was shortened by 98.7%,the overshoot was reduced by 5.1%,and the control error was 0.2%-0.5%when the system was stabilized.The optimized fuzzy control system had fast adjustment speeds,precise force control and stability.The experimental analysis of the surface morphology of the machined blade was carried out by the industrial robot abrasive grinding mechanism,and the correctness of the theoretical analysis and the effectiveness of the control strategy were verified. 展开更多
关键词 grinding mechanism constant force control strategy fuzzy control proportion integration differentiation(PID)
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Thinking about Value Realization of Ecological Products under the Background of Urban-rural Integration in Chengdu“Western Control”Area
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作者 ZHANG Xuequan ZHANG Yi 《Journal of Landscape Research》 2023年第2期59-62,共4页
Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural developmen... Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural development in the new era will realize the balanced development of urban and rural areas and give full play to the value of rural ecological resources through the“powerful combination”of urban and rural areas.To realize the urban-rural integration and high-quality rural development in Chengdu“western control”area,it is necessary to enhance the awareness of ecological resources and ecological products,and carry out unified planning of ecological infrastructure,ecological material products and ecological service products in the whole“western control”area.Meantime,ecological restoration must be carried out scientifically,and scene design for value transformation of ecological products should be implemented innovatively. 展开更多
关键词 Western control Urban-rural integration Ecological products Ecological value transformation
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Integration of Fault Analysis and Interlock Controller Synthesis for Batch Processes 被引量:2
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作者 Susumu Hashizume Tomoyuki Yajima Yukiko Kuwashita Katsuaki Onogi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期57-61,共5页
Integration amongst various decision-making processes, such as planning, design, and operation is necessary to dynamic and flexible batch production. To achieve a batch production integration, utilization of common mo... Integration amongst various decision-making processes, such as planning, design, and operation is necessary to dynamic and flexible batch production. To achieve a batch production integration, utilization of common models used for various decision-making processes is an effective approach. From this point of view, a batch system common model as described by a Petri net is proposed. In this article, a fault diagnosis technique for batch processes is presented using information about fault propagation and the possibilities of integration of fault analysis and controller synthesis are discussed on the basis of the Petri net based common models. 展开更多
关键词 fault diagnosis batch control integration discrete event system Petri net
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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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Construction and Application of Soil Erosion Control and Circular Agriculture Mode in Hilly Red Soil of Southern China 被引量:2
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作者 翁伯琦 钟珍梅 +3 位作者 罗旭辉 应朝阳 王义祥 叶菁 《Agricultural Science & Technology》 CAS 2012年第7期1536-1542,1557,共8页
[Objective] The paper was to construct soil erosion control and circular agriculture mode in hilly red soil of southern China, and analyze its application effort. [Method] The cause of soil erosion in hilly red soil o... [Objective] The paper was to construct soil erosion control and circular agriculture mode in hilly red soil of southern China, and analyze its application effort. [Method] The cause of soil erosion in hilly red soil of southern China and the reason for long-term treatment without remarkable effort were analyzed. On this basis, the key technology, economic benefit, ecological service function and carbon sequestration sink enhancement effect of various modes were further analyzed. [Result] The basic idea for comprehensive control of hilly soil erosion in southern China was as follows: the control of soil erosion was combined with modern agricultural production, in order to build "fruit(tea)-grass-livestock-methane" circular agriculture mode with comprehensive control of soil erosion; application effect analysis showed that the establishment of circular agriculture mode in southern hilly area to control soil erosion had remarkable effect, which could simultaneously meet the coordinated development of ecological, economic and social benefits. [Conclusion] This study established an effective mode suitable for soil erosion control and agricultural protection development in southern red soil mountain, which could drive the sustainable development of ecological restoration of mountainous area and rural agricultural economy. 展开更多
关键词 Red soil hilly region Soil erosion control Integrated productivity Emergy analysis Carbon sequestration sink enhancement
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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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Research on the Construction Mode of Mechanical and Electrical Integration of Intelligent Control System based on Multi-agent Technique
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作者 Xiaofeng Xu 《International Journal of Technology Management》 2016年第2期16-18,共3页
In this paper, we conduct research on the construction mode of mechanical and electrical integration of intelligent control system based on the multi-agent technique. The development of the modem science and technolog... In this paper, we conduct research on the construction mode of mechanical and electrical integration of intelligent control system based on the multi-agent technique. The development of the modem science and technology has greatly promoted the cross of different subjects and infiltration, caused the technological transformation and revolution in the field of engineering. In the field of mechanical engineering, because of rapid development of microelectronics technology and computer technology to the mechanical industry and its mechanical and electrical integration, which is formed by the penetration of the technology of mechanical industry structure, product, organization, function and structure, mode of the production and management system, great changes have taken place in industrial production by the mechanical electrification "ushered in the development of" mechatronics "as the characteristics of the stage. Our research combines the multi-agent technique to propose the new paradigm for mechanical and electrical integration which is innovative. 展开更多
关键词 Construction Mode integration Intelligent control Multi-agent Technique.
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Redundant Data Detection and Deletion to Meet Privacy Protection Requirements in Blockchain-Based Edge Computing Environment
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作者 Zhang Lejun Peng Minghui +6 位作者 Su Shen Wang Weizheng Jin Zilong Su Yansen Chen Huiling Guo Ran Sergey Gataullin 《China Communications》 SCIE CSCD 2024年第3期149-159,共11页
With the rapid development of information technology,IoT devices play a huge role in physiological health data detection.The exponential growth of medical data requires us to reasonably allocate storage space for clou... With the rapid development of information technology,IoT devices play a huge role in physiological health data detection.The exponential growth of medical data requires us to reasonably allocate storage space for cloud servers and edge nodes.The storage capacity of edge nodes close to users is limited.We should store hotspot data in edge nodes as much as possible,so as to ensure response timeliness and access hit rate;However,the current scheme cannot guarantee that every sub-message in a complete data stored by the edge node meets the requirements of hot data;How to complete the detection and deletion of redundant data in edge nodes under the premise of protecting user privacy and data dynamic integrity has become a challenging problem.Our paper proposes a redundant data detection method that meets the privacy protection requirements.By scanning the cipher text,it is determined whether each sub-message of the data in the edge node meets the requirements of the hot data.It has the same effect as zero-knowledge proof,and it will not reveal the privacy of users.In addition,for redundant sub-data that does not meet the requirements of hot data,our paper proposes a redundant data deletion scheme that meets the dynamic integrity of the data.We use Content Extraction Signature(CES)to generate the remaining hot data signature after the redundant data is deleted.The feasibility of the scheme is proved through safety analysis and efficiency analysis. 展开更多
关键词 blockchain data integrity edge computing privacy protection redundant data
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Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids
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作者 Li-Li Yang Ze-Yu Liu +3 位作者 Shi-bo Wang Xian-Bo He Guan-Cheng Jiang Jie Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期551-566,共16页
With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to r... With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore instability.In this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite partly.The suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of 2.The viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same density.Through multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of WBDFs.The sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was 0.2603.Therefore,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection capacity.This work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs. 展开更多
关键词 Drilling fluids Weighting materials Filtration control Reservoir protection Stability property
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