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Optimizing Grey Wolf Optimization: A Novel Agents’ Positions Updating Technique for Enhanced Efficiency and Performance
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作者 Mahmoud Khatab Mohamed El-Gamel +2 位作者 Ahmed I. Saleh Asmaa H. Rabie Atallah El-Shenawy 《Open Journal of Optimization》 2024年第1期21-30,共10页
Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of ... Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of the agents’ positions relative to the leader wolves. In this paper, we provide a brief overview of the Grey Wolf Optimization technique and its significance in solving complex optimization problems. Building upon the foundation of GWO, we introduce a novel technique for updating agents’ positions, which aims to enhance the algorithm’s effectiveness and efficiency. To evaluate the performance of our proposed approach, we conduct comprehensive experiments and compare the results with the original Grey Wolf Optimization technique. Our comparative analysis demonstrates that the proposed technique achieves superior optimization outcomes. These findings underscore the potential of our approach in addressing optimization challenges effectively and efficiently, making it a valuable contribution to the field of optimization algorithms. 展开更多
关键词 Grey Wolf optimization (GWO) Metaheuristic Algorithm optimization Problems Agents’ positions Leader Wolves optimal Fitness Values optimization Challenges
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Paradigm for Determining the Optimal Ultradeep and Superthick Saline Aquifer for High-TDS Mine Water Geological Storage
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作者 LI Xin CHEN Ge +3 位作者 XU Zhimin LIU Qi CHEN Tianci SUN Yajun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期771-785,共15页
Saline aquifers are the most popular waste and CO_(2)injection and storage reservoirs worldwide.This project proposes that several optimal injection positions should be investigated as hydraulic pressure-focused posit... Saline aquifers are the most popular waste and CO_(2)injection and storage reservoirs worldwide.This project proposes that several optimal injection positions should be investigated as hydraulic pressure-focused positions,in order to relieve the high demands of pump performance.The comprehensive indices(F_(i))representing the injectivity of different burial depths were obtained by using information entropy,based on the mercury injection experimental data of 13 rock samples.The results demonstrated that the burial depths of No.4,No.1 and No.2 in the Liujiagou Formation were the most suitable positions for hydraulic focused injection,which means the upper 30 m thickness could be regarded as the hydraulic focused range in the saline aquifer with an average thickness of 400 m.In addition,some laboratory experiments and in situ tests were carried out for the purpose of certifying and analyzing results,including SEM,XRD,brittleness index and logging.The results suggested that the rock samples at the No.4,No.1 and No.2 burial depth ranges have loose microstructure,weak cementation,as well as dual pores and fractures.The lithology is mainly quartz and feldspar,but the clay mineral content is high(10%-25%),which is positive for dissolution.The lithology is suitable for hydraulic fracturing to form extended cracks and micro-fissures during high-TDS(total dissolved solids)mine water injection,because of the high brittleness index.Finally,a theoretical and technical framework for high-TDS mine water injection was established,based on operating pilot engineering.Some theoretical defects and drawbacks learned from the field practices were summarized and solutions proposed.The research in this study could provide guidance and a paradigm for the inexpensive treatment of high-TDS mine water by injection and storage. 展开更多
关键词 ultradeep Liujiagou Formation high-TDS mine water optimal hydraulic injection positions information entropy reservoir spatial characteristics
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Position Optimization for Mobile Relay Communications with Constrained Energy over a Whole Horizontal Plane
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作者 Haijun Tan Ning Xie 《China Communications》 SCIE CSCD 2023年第5期340-350,共11页
This paper concerns the position optimization problem of a mobile relay over a whole horizontal plane.This problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,r... This paper concerns the position optimization problem of a mobile relay over a whole horizontal plane.This problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,reliability,connectivity,and data rate.In this paper,we propose a new position optimization scheme of a mobile relay over a whole horizontal plane based on the one-bit feedback information from the destination node,which improves the performance over the prior scheme whose position of the mobile relay is optimized over a fixed orbit.In the proposed scheme,the mobile relay is equipped with merely one single onboard antenna.Moreover,no prior information about the positions of both the source node and the destination node is required.Thus,the proposed scheme can work at low network resources scenario,which is particularly suitable for mobile relay communication with constrained energy,e.g.,the communications in a disaster area where the infrastructure is heavily damaged,volcano monitoring,and wireless powered communication networking.According to the characteristics of the proposed scheme,we further design two heuristic implementations to calculate the optimal position of a mobile relay over a whole horizontal plane.The first implementation has better steady performance whereas the second implementation has better convergence speed.We implement the proposed scheme and conduct an extensive performance comparison between the proposed scheme and prior schemes to verify the advantages of the proposed scheme. 展开更多
关键词 mobile relay position optimization one bit feedback information whole horizontal plane energy constrained
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Information Method for Synthesis of Optimal Data Subsystems Designated for Positioning, Location and Remote Sensing Systems 被引量:1
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作者 Hikmat Hamid Asadov Kamal Kheyraddin Ismaylov 《Positioning》 2011年第1期61-64,共4页
The general classification of information systems of remote action, including such system as positioning systems, location systems and remote sensing systems is suggested. In view of formulated limitation conditions t... The general classification of information systems of remote action, including such system as positioning systems, location systems and remote sensing systems is suggested. In view of formulated limitation conditions the common mathematical information model of data transfer subsystems of considered systems is suggested. The optimization of developed information model is carried out and the optimal operation regimes of these data transfer subsystems are 展开更多
关键词 Synthesis SUBSYSTEMS optimization REMOTE SENSING positionING LOCATION
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Optimal predication of double-star position/SINS based on discrete integration
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作者 林雪原 何友 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期179-182,共4页
Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of D... Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of Double-Star positioning system and the SINS is one of the developing directions for an integrated navigation system. This paper puts forward an optimal predication method of Double-Star/SINS integrated system based on discrete integration, which can make use of the delayed position information of Double-Star positioning system to optimally predicate the integrated system, and then corrects the SINS. The experimental results show that this method can increase the user's concealment under the condition of assuring the system's accuracy. 展开更多
关键词 discrete integration optimal predication Double-Star positioning system SINS
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Determination of Optimal Cash Position of Mutual Fund
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作者 陈铭新 张世英 《Transactions of Tianjin University》 EI CAS 2003年第1期75-78,共4页
Cash position, held by mutual fund with purpose to satisfy investors′ redemption, will inevitably generate certain amount of cost. In this paper, the total cost caused by cash position is divided into opportunity cos... Cash position, held by mutual fund with purpose to satisfy investors′ redemption, will inevitably generate certain amount of cost. In this paper, the total cost caused by cash position is divided into opportunity cost and shortage cost, and a model is constructed to describe the relationship between total cost and cash position along with investors′ purchase and redemption, from which the formula of optimal cash position is deduced. Finally, the adjustment of optimal cash position in different market situations is discussed. 展开更多
关键词 investors′ purchase and redemption opportunity cost shortage cost optimal cash position
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TOA positioning algorithm of LBL system for underwater target based on PSO 被引量:2
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作者 XING Yao WANG Jiongqi +3 位作者 HE Zhangming ZHOU Xuanying CHEN Yuyun PAN Xiaogang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1319-1332,共14页
For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlin... For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlinear iteration.However,due to the complex underwater environment,the sound speed changes with time and space,and then the acoustic propagation path is actually a curve,which inevitably causes some errors to the traditional distance intersection positioning algorithm.To reduce the position error caused by the uncertain underwater sound speed,a new time of arrival(TOA)intersection underwater positioning algorithm of LBL system is proposed.Firstly,combined with the vertical layered model of the underwater sound speed,an implicit positioning model of TOA intersection is constructed through the constant gradient acoustic ray tracing.And then an optimization function based on the overall TOA residual square sum is advanced to solve the position parameters for the underwater target.Moreover,the particle swarm optimization(PSO)algorithm is replaced with the tra-ditional nonlinear least square method to optimize the implicit positioning model of TOA intersection.Compared with the traditional distance intersection positioning model,the TOA intersec-tion positioning model is more suitable for the engineering practice and the optimization algorithm is more effective.Simulation results show that the proposed methods in this paper can effectively improve the positioning accuracy for the underwater target. 展开更多
关键词 long baseline(LBL)positioning system sound speed profile constant gradient acoustic ray tracing time of arrival(TOA)intersection model particle swarm optimization(PSO)
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Analytical optimization on GNSS buoy array for underwater positioning 被引量:5
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作者 Ke Qi Guoqing Qu +4 位作者 Shuqiang Xue Tianhe Xu Xiaoqing Su Yixu Liu Jun Wan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期137-143,共7页
Global navigation satellite system(GNSS)/acoustic positioning precision is determined by the positioning geometry and the ranging precision;thus optimizing GNSS buoys array is meaningful to improve the positioning acc... Global navigation satellite system(GNSS)/acoustic positioning precision is determined by the positioning geometry and the ranging precision;thus optimizing GNSS buoys array is meaningful to improve the positioning accuracy and reliability.An analytical method is proposed for optimizing the GNSS buoys array with regard to the cutoff angle constraints for underwater acoustic observations.For the practical limitation of coplanarity of GNSS buoys and the cutoff angle,an algorithm is proposed to analytically minimize the position dilution of precision(PDOP).The proposed method is validated to give complete solutions of PDOP minimization with five GNSS buoys.At last,in order to search a best configuration among the PDOP solution set,we propose a search algorithm to get the solution with the smallest geometric dilution of precision(GDOP).It indicates that within a given region,the GDOP minimization at the center of a region is equivalent to the PDOP mean minimization over the region.The relation between the positioning accuracy and the positioning geometry with five known points is illustrated in an experiment performed in South China Sea. 展开更多
关键词 UNDERWATER positionING GNSS BUOY GDOP optimIZATION
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Position Control Optimization of Aerodynamic Brake Device for High-speed Trains 被引量:2
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作者 ZUO Jianyong LUO Zhuojun CHEN Zhongkai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期287-295,共9页
The aerodynamic braking is a clean and non-adhesion braking, and can be used to provide extra braking force during high-speed emergency braking. The research of aerodynamic braking has attracted more and more attentio... The aerodynamic braking is a clean and non-adhesion braking, and can be used to provide extra braking force during high-speed emergency braking. The research of aerodynamic braking has attracted more and more attentions in recent years. However, most researchers in this field focus on aerodynamic effects and seldom on issues of position control of the aerodynamic braking board. The purpose of this paper is to explore position control optimization of the braking board in an aerodynamic braking prototype. The mathematical models of the hydraulic drive unit in the aerodynamic braking system are analyzed in detail, and the simulation models are established. Three control functions--constant, linear, and quadratic--are explored. Two kinds of criteria, including the position steady-state error and the acceleration of the piston rod, are used to evaluate system performance. Simulation results show that the position steady state-error is reduced from around 12-2 mm by applying a linear instead of a constant function, while the acceleration is reduced from 25,71-3.70 m/s2 with a quadratic control function. Use of the quadratic control function is shown to improve system performance. Experimental results obtained by measuring the position response of the piston rod on a test-bench also suggest a reduced position error and smooth movement of the piston rod. This implies that the acceleration is smaller when using the quadratic function, thus verifying the effectiveness of control schemes to improve to system performance. This paper proposes an effective and easily implemented control scheme that improves the position response of hydraulic cylinders during position control. 展开更多
关键词 high-speed train aerodynamic brake HYDRAULIC position control optimization.
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Optimization of the cavity beam-position monitor system for the Shanghai soft X-ray free-electron laser user facility 被引量:3
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作者 Jian Chen Yong-Bin Leng +2 位作者 Lu-Yang Yu Long-Wei Lai Ren-Xian Yuan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第10期22-32,共11页
To achieve high-efficiency operation of the highgain free-electron laser(FEL),the electron beams and radiated photon beams need to be overlapped precisely and pass through the entire undulator section.Therefore,a high... To achieve high-efficiency operation of the highgain free-electron laser(FEL),the electron beams and radiated photon beams need to be overlapped precisely and pass through the entire undulator section.Therefore,a high-resolution beam-position monitor(BPM)is required.A cavity BPM(CBPM)with a resonant cavity structure was developed and used in the Shanghai Soft X-ray FEL(SXFEL)test facility and can achieve a position resolution of<1μm.The construction and operation of the SXFEL user facility also bring about higher requirements for beamposition measurement.In this case,the factors that affect the performance of the CBPM system were further analyzed.These included the amplitude and phase stability of the local oscillator,stability of the trigger signal,performance of the radio frequency front-end,signal processing electronics,and signal processing algorithms.Based on the upgrade and optimization of the system,a beam test platform was built at the end of the linear acceleration section of the SXFEL,and the experimental results show that the position resolution of the system can reach 177 nm at a bunch charge of 500 pC,and the dynamic range is controlled within±300μm,and the relative measurement uncertainty of the bunch charge can reach 0.021%,which are significant improvements compared to the attributes of the previous system. 展开更多
关键词 Cavity BPM SXFEL System optimization position resolution Measurement uncertainty ALGORITHM
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New Three-Dimensional Assessment Model and Optimization of Acoustic Positioning System 被引量:1
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作者 Lin Zhao Xiaobo Chen +3 位作者 Jianhua Cheng Lianhua Yu Chengcai Lv Jiuru Wang 《Computers, Materials & Continua》 SCIE EI 2020年第8期1005-1023,共19页
This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate th... This paper addresses the problem of assessing and optimizing the acoustic positioning system for underwater target localization with range measurement.We present a new three-dimensional assessment model to evaluate the optimal geometric beacon formation whether meets user requirements.For mathematical tractability,it is assumed that the measurements of the range between the target and beacons are corrupted with white Gaussian noise with variance,which is distance-dependent.Then,the relationship between DOP parameters and positioning accuracy can be derived by adopting dilution of precision(DOP)parameters in the assessment model.In addition,the optimal geometric beacon formation yielding the best performance can be achieved via minimizing the values of geometric dilution of precision(GDOP)in the case where the target position is known and fixed.Next,in order to ensure that the estimated positioning accuracy on the region of interest satisfies the precision required by the user,geometric positioning accuracy(GPA),horizontal positioning accuracy(HPA)and vertical positioning accuracy(VPA)are utilized to assess the optimal geometric beacon formation.Simulation examples are designed to illustrate the exactness of the conclusion.Unlike other work that only uses GDOP to optimize the formation and cannot assess the performance of the specified size,this new three-dimensional assessment model can evaluate the optimal geometric beacon formation for each dimension of any point in three-dimensional space,which can provide guidance to optimize the performance of each specified dimension. 展开更多
关键词 Acoustic positioning system three-dimensional assessment model positioning accuracy DOP optimal configuration
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Optimized parameters of downhole all-metal PDM based on genetic algorithm
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作者 Jia-Xing Lu Ling-Rong Kong +2 位作者 Yu Wang Chao Feng Yu-Lin Gao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2663-2676,共14页
Currently,deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors.The all-metal positive displacement motor,known for its robust performance,... Currently,deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors.The all-metal positive displacement motor,known for its robust performance,is a critical choice for such drilling.The dimensions of the PDM are crucial for its performance output.To enhance this,optimization of the motor's profile using a genetic algorithm has been undertaken.The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid.These curves are then refined using the least squares method for a precise fit.Following this,the PDM's mathematical model is optimized,and motor friction is assessed.The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions,including the isometric radius coefficient,eccentricity distance parameter,overflow area,and maximum slip speed.This optimization yields the ideal profile parameters that enhance the motor's output.Comparative analyses of the initial and optimized output characteristics were conducted,focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance.Results indicate that the optimized motor's overflow area increased by 6.9%,while its rotational speed reduced by 6.58%.The torque,as tested by Infocus,saw substantial improvements of38.8%.This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology. 展开更多
关键词 positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area
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Optimization Method of Bearing Support Positions in a High-Speed Flexible Rotor System
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作者 TANG Changke JIANG Yanhong LIU Jing 《Journal of Donghua University(English Edition)》 EI CAS 2020年第6期504-511,共8页
Bearing support position is one of main factors affecting vibration characteristics of rotor systems. To optimize the bearing support positions in a high-speed flexible rotor system (HSFRS) based on the vibration char... Bearing support position is one of main factors affecting vibration characteristics of rotor systems. To optimize the bearing support positions in a high-speed flexible rotor system (HSFRS) based on the vibration characteristics, an optimization method of bearing support positions in the HSFRS is proposed. In this method, a finite element (FE) model of a high-speed flexible rotor (HSFR) was established. The natural frequencies and mode shapes of the HSFRS were used to obtain the initial design scheme of the bearing support positions. A frequency characteristic equation of the HSFRS was established to obtain the critical speeds of the HSFRS. And a dynamic model of the HSFRS was established to analyze the vibration characteristics for different bearing support position cases. The problem of optimizing bearing support positions in the HSFRS was solved by the developed method. The results showed that vibration amplitudes of the HSFRS were more stable when the bearing support positions were optimized. This study can provide a new method for optimizing bearing support positions of rotor systems. 展开更多
关键词 flexible rotor system optimal design vibration characteristic bearing support position
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The Topology Optimization of Oil Cylinder Mounting
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作者 LI Zhibin 《International Journal of Plant Engineering and Management》 2024年第1期55-62,共8页
The method of the structural topology optimization is often used to design machine in the early stage of the mechanical design.And the mechanical structures use the topology design to produce a new still and lightweig... The method of the structural topology optimization is often used to design machine in the early stage of the mechanical design.And the mechanical structures use the topology design to produce a new still and lightweight part with the different loading.A new structure is created through overlapping these new optimized structure. 展开更多
关键词 static analysis negative force positive force topology optimization angle range
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Catalytic Hydrothermal Liquefaction of Water Hyacinth Using Fe3O4/NiO Nanocomposite: Optimization of Reaction Conditions by Response Surface Methodology
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作者 Godwin Aturagaba Dan Egesa +1 位作者 Edward Mubiru Emmanuel Tebandeke 《Journal of Sustainable Bioenergy Systems》 2023年第3期73-98,共26页
This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanoc... This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanocomposite was synthesized by the co-precipitation method and used in the hydrothermal liquefaction of water hyacinth. The composition and structural morphology of the synthesized catalysts were determined using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic absorption spectroscopy (AAS). The particle size distribution of the catalyst nanoparticles was determined by the Image J software. Three reaction parameters were optimized using the response surface methodology (RSM). These were: temperature, residence time, and catalyst dosage. A maximum bio-oil yield of 59.4 wt% was obtained using iron oxide/nickel oxide nanocomposite compared to 50.7 wt% obtained in absence of the catalyst. The maximum bio-oil yield was obtained at a temperature of 320°C, 1.5 g of catalyst dosage, and 60 min of residence time. The composition of bio-oil was analyzed using gas chromatography-mass spectroscopy (GC-MS) and elemental analysis. The GC-MS results showed an increase of hydrocarbons from 58.3% for uncatalyzed hydrothermal liquefaction to 88.66% using iron oxide/nickel oxide nanocomposite. Elemental analysis results revealed an increase in the hydrogen and carbon content and a reduction in the Nitrogen, Oxygen, and Sulphur content of the bio-oil during catalytic HTL compared to HTL in absence of catalyst nanoparticles. The high heating value increased from 33.5 MJ/Kg for uncatalyzed hydrothermal liquefaction to 38.6 MJ/Kg during the catalytic HTL. The catalyst nanoparticles were recovered from the solid residue by sonication and magnetic separation and recycled. The recycled catalyst nanoparticles were still efficient as hydrothermal liquefaction (HTL) catalysts and were recycled four times. The application of iron oxide/ nickel oxide nanocomposites in the HTL of water hyacinth increases the yield of bio-oil and improves its quality by reducing hetero atoms thus increasing its energy performance as fuel. Iron oxide/nickel oxide nanocomposites used in this study are widely available and can be easily recovered magnetically and recycled. This will potentially lead to an economical, environmentally friendly, and sustainable way of converting biomass into biofuel. 展开更多
关键词 Catalytic Hydrothermal Liquefaction Water Hyacinth BIO-OIL Central Com-posite Design Response Surface Methodology optimIZATION
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Optimal regularity of positive solutions of the Hénon-Hardy equation and related equations
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作者 Zongming Guo Fangshu Wan 《Science China Mathematics》 SCIE CSCD 2024年第10期2283-2302,共20页
We present a new method to determine the optimal regularity of positive solutions u∈C^(4)(Ω\{0})∩C^(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■RN(N≥4) is a bounded smoot... We present a new method to determine the optimal regularity of positive solutions u∈C^(4)(Ω\{0})∩C^(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■RN(N≥4) is a bounded smooth domain with 0∈Ω,α>-4,and p∈R.It is clear that 0 is an isolated singular point of solutions of(0.1) and the optimal regularity of u in Ω relies on the parameter α.It is also important to see that the regularity of u at x=0 determines the regularity of u in Ω.We first establish asymptotic expansions up to arbitrary orders at x=0 of prescribed positive solutions u ∈C^(4)(Ω{0}) ∩ C^(0)(Ω)of(0.1).Then we show that the regularity at x=0 of each positive solution u of(0.1) can be determined by some terms in asymptotic expansions of the related positive radial solution of the equation(0.1) with Ω=B,where B is the unit ball of R^(N).The main idea works for more general equations with singular weights. 展开更多
关键词 H´enon-Hardy equation positive solutions optimal regularity singular point asymptotic expansions
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Design and Parameter Optimization of Zero Position Code Considering Diffraction Based on Deep Learning Generative Adversarial Networks
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作者 Shengtong Wang Linbin Luo Xinghui Li 《Nanomanufacturing and Metrology》 EI 2024年第1期15-27,共13页
Absolute measurement has consistently been the primary focus in the development of precision linear and angular displace-ment measurements.The scheme design of binary zero position codes is an important factor for abs... Absolute measurement has consistently been the primary focus in the development of precision linear and angular displace-ment measurements.The scheme design of binary zero position codes is an important factor for absolute measurement.Designing and optimizing high-bit zero position codes with over 100 bits face considerable challenges.Simultaneously,the working parameters of zero position codes[unit code width(b),distance(d),and yaw angle(α)]remarkably affect their post-installation performance,particularly in absolute positioning and limit code application in multi-degree-of-freedom measurement schemes.This study addresses these challenges by proposing a design method for zero position codes that considers diffraction based on generative adversarial networks and aims to explore a design with increased efficiency and accuracy as well as optimization for high-bit zero position codes.Additionally,the tolerance range of zero positioning per-formance for each working parameter is examined.By leveraging the adversarial network structure,this study generates the optimization of a 150-bit code and processes the tests of the zero position code by using simulation results.The following working parameter ranges for code design are recommended on the basis of theoretical and experimental results:b greater than 10μm,d andαwithin 1000μm and 3490μrad,and avoidance of intervals with sharp changes in the full width at half maximum.The proposed code design and parameter optimization lay a solid foundation for research and engineering appli-cations in absolute measurement field and have considerable potential for generalization and wide applicability. 展开更多
关键词 Absolute measurement Zero position code Deep learning Generative adversarial networks Tolerance range Parameter optimization
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Simulation-based Optimal Design of α-β-γ-δ Filter 被引量:1
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作者 Chun-Mu Wu Paul P. Lin +1 位作者 Zhen-Yu Han Shu-Rong Li 《International Journal of Automation and computing》 EI 2010年第2期247-253,共7页
The existing third-order tracker known as α-β-γ-δ filter has been used for target tracking and predicting for years. The filter can track the target's position and velocity, but not the acceleration. To extend it... The existing third-order tracker known as α-β-γ-δ filter has been used for target tracking and predicting for years. The filter can track the target's position and velocity, but not the acceleration. To extend its capability, a new fourth-order target tracker called α-β-γ-δ filter is proposed. The main objective of this study was to find the optimal set of filter parameters that leads to minimum position tracking errors. The tracking errors between using the α-β-γ-δ filter and the α-β-γ-δ filter are compared. As a result, the new filter exhibits significant improvement in position tracking accuracy over the existing third-order filter, but at the expense of computational time in search of the optimal filter. To reduce the computational time, a simulation-based optimization technique via Taguchi method is introduced. 展开更多
关键词 Filter design simulation-based optimization Taguchi methods position tracking velocity tracking acceleration tracking.
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Design and Implementation of Digital Fractional Order PID Controller Using Optimal Pole-Zero Approximation Method for Magnetic Levitation System 被引量:3
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作者 Amit S.Chopade Swapnil W.Khubalkar +2 位作者 A.S.Junghare M.V.Aware Shantanu Das 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第5期977-989,共13页
The aim of this paper is to employ fractional order proportional integral derivative(FO-PID)controller and integer order PID controller to control the position of the levitated object in a magnetic levitation system(M... The aim of this paper is to employ fractional order proportional integral derivative(FO-PID)controller and integer order PID controller to control the position of the levitated object in a magnetic levitation system(MLS),which is inherently nonlinear and unstable system.The proposal is to deploy discrete optimal pole-zero approximation method for realization of digital fractional order controller.An approach of phase shaping by slope cancellation of asymptotic phase plots for zeros and poles within given bandwidth is explored.The controller parameters are tuned using dynamic particle swarm optimization(d PSO)technique.Effectiveness of the proposed control scheme is verified by simulation and experimental results.The performance of realized digital FO-PID controller has been compared with that of the integer order PID controllers.It is observed that effort required in fractional order control is smaller as compared with its integer counterpart for obtaining the same system performance. 展开更多
关键词 Approximation methods digital control dis-cretization fractional calculus fractional order PID controller(FO-PID) magnetic levitation particle swarm optimization(PSO) position control.
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A GPS/BDS dual-mode positioning algorithm for a train based on CIPSO_EKF 被引量:2
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作者 LUO Miao DANG Jianwu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期12-20,共9页
When using global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode navigation system to locate a train,Kalman filter that is used to calculate train position has to be adjusted according to the feature... When using global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode navigation system to locate a train,Kalman filter that is used to calculate train position has to be adjusted according to the features of the dual-mode observation.Due to multipath effect,positioning accuracy of present Kalman filter algorithm is really low.To solve this problem,a chaotic immune-vaccine particle swarm optimization_extended Kalman filter(CIPSO_EKF)algorithm is proposed to improve the output accuracy of the Kalman filter.By chaotic mapping and immunization,the particle swarm algorithm is first optimized,and then the optimized particle swarm algorithm is used to optimize the observation error covariance matrix.The optimal parameters are provided to the EKF,which can effectively reduce the impact of the observation value oscillation caused by multipath effect on positioning accuracy.At the same time,the train positioning results of EKF and CIPSO_EKF algorithms are compared.The eastward position errors and velocity errors show that CIPSO_EKF algorithm has faster convergence speed and higher real-time performance,which can effectively suppress interference and improve positioning accuracy. 展开更多
关键词 global positioning system/BeiDou navigation satellite(GPS/BDS)dual-mode positioning chaotic immune-vaccine particle swarm optimization(CIPSO) extended Kalman filter(EKF) positioning accuracy
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