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Optimizing a Transportation System Using Metaheuristics Approaches (EGD/GA/ACO): A Forest Vehicle Routing Case Study
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作者 Hossein Havaeji Thien-My Dao Tony Wong 《World Journal of Engineering and Technology》 2024年第1期141-157,共17页
The large-scale optimization problem requires some optimization techniques, and the Metaheuristics approach is highly useful for solving difficult optimization problems in practice. The purpose of the research is to o... The large-scale optimization problem requires some optimization techniques, and the Metaheuristics approach is highly useful for solving difficult optimization problems in practice. The purpose of the research is to optimize the transportation system with the help of this approach. We selected forest vehicle routing data as the case study to minimize the total cost and the distance of the forest transportation system. Matlab software helps us find the best solution for this case by applying three algorithms of Metaheuristics: Genetic Algorithm (GA), Ant Colony Optimization (ACO), and Extended Great Deluge (EGD). The results show that GA, compared to ACO and EGD, provides the best solution for the cost and the length of our case study. EGD is the second preferred approach, and ACO offers the last solution. 展开更多
关键词 Metaheuristics Algorithms Transportation Costs Optimization approach Cost Minimisation
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Organic cathode materials for rechargeable magnesium-ion batteries:Fundamentals, recent advances, and approaches to optimization
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作者 Xiaoqian He Ruiqi Cheng +6 位作者 Xinyu Sun Hao Xu Zhao Li Fengzhan Sun Yang Zhan Jianxin Zou Richard M.Laine 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4359-4389,共31页
Rechargeable magnesium-ion batteries(MIBs) are favorable substitutes for conventional lithium-ion batteries(LIBs) because of abundant magnesium reserves, a high theoretical energy density, and great inherent safety. O... Rechargeable magnesium-ion batteries(MIBs) are favorable substitutes for conventional lithium-ion batteries(LIBs) because of abundant magnesium reserves, a high theoretical energy density, and great inherent safety. Organic electrode materials with excellent structural tunability,unique coordination reaction mechanisms, and environmental friendliness offer great potential to promote the electrochemical performance of MIBs. However, research on organic magnesium battery cathode materials is still preliminary with many significant challenges to be resolved including low electrical conductivity and unwanted but severe dissolution in useful electrolytes. Herein, we provide a detailed overview of reported organic cathode materials for MIBs. We begin with basic properties such as charge storage mechanisms(e.g., n-, p-, and bipolartype), moving to recent advances in various types of organic cathodes including carbonyl-, nitrogen-, and sulfur-based materials. To shed light on the diverse strategies targeting high-performance Mg-organic batteries, elaborate summaries of various approaches are presented.Generally, these strategies include molecular design, polymerization, mixing with carbon, nanosizing and electrolyte/separator optimization.This review provides insights on exploring high-performance organic cathodes in rechargeable MIBs. 展开更多
关键词 Mg-organic batteries Organic cathode materials Energy storage Charge storage mechanism Electrochemical optimization approaches
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Classification of Conversational Sentences Using an Ensemble Pre-Trained Language Model with the Fine-Tuned Parameter
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作者 R.Sujatha K.Nimala 《Computers, Materials & Continua》 SCIE EI 2024年第2期1669-1686,共18页
Sentence classification is the process of categorizing a sentence based on the context of the sentence.Sentence categorization requires more semantic highlights than other tasks,such as dependence parsing,which requir... Sentence classification is the process of categorizing a sentence based on the context of the sentence.Sentence categorization requires more semantic highlights than other tasks,such as dependence parsing,which requires more syntactic elements.Most existing strategies focus on the general semantics of a conversation without involving the context of the sentence,recognizing the progress and comparing impacts.An ensemble pre-trained language model was taken up here to classify the conversation sentences from the conversation corpus.The conversational sentences are classified into four categories:information,question,directive,and commission.These classification label sequences are for analyzing the conversation progress and predicting the pecking order of the conversation.Ensemble of Bidirectional Encoder for Representation of Transformer(BERT),Robustly Optimized BERT pretraining Approach(RoBERTa),Generative Pre-Trained Transformer(GPT),DistilBERT and Generalized Autoregressive Pretraining for Language Understanding(XLNet)models are trained on conversation corpus with hyperparameters.Hyperparameter tuning approach is carried out for better performance on sentence classification.This Ensemble of Pre-trained Language Models with a Hyperparameter Tuning(EPLM-HT)system is trained on an annotated conversation dataset.The proposed approach outperformed compared to the base BERT,GPT,DistilBERT and XLNet transformer models.The proposed ensemble model with the fine-tuned parameters achieved an F1_score of 0.88. 展开更多
关键词 Bidirectional encoder for representation of transformer conversation ensemble model fine-tuning generalized autoregressive pretraining for language understanding generative pre-trained transformer hyperparameter tuning natural language processing robustly optimized BERT pretraining approach sentence classification transformer models
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The Optimized Way of Commercial Bank Management under the Background of Big Data
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作者 Tailin Zhu 《Proceedings of Business and Economic Studies》 2020年第3期21-24,共4页
With the advent of the era of big data,the commercial management activities of commercial banks are facing both new challenges and new development opportunities.In the increasingly fierce market competition,commercial... With the advent of the era of big data,the commercial management activities of commercial banks are facing both new challenges and new development opportunities.In the increasingly fierce market competition,commercial banks must pay attention to enhance their core competitiveness,only in this way can they occupy a certain advantage in the fierce market environment.Therefore,commercial banks must accurately grasp the development opportunities brought by big data,and further strengthen the optimization of business management.The author explores and analyzes the impact of big data on commercial banks,and puts forward an effective way for commercial banks to optimize business management in the context of big data,hoping to contribute to the long-term development of commercial banks. 展开更多
关键词 Big data Commercial Bank Business management Optimization approach
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Robust parametric approach for tracking control of an air-breathing hypersonic cruise vehicle
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作者 蔡光斌 段广仁 +1 位作者 胡昌华 谭峰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第1期58-64,共7页
To realize the stabilization and the tracking of flight control for an air-breathing hypersonic cruise vehicle, the linearization of the longitudinal model under trimmed cruise condition is processed firstly. Furtherm... To realize the stabilization and the tracking of flight control for an air-breathing hypersonic cruise vehicle, the linearization of the longitudinal model under trimmed cruise condition is processed firstly. Furthermore, the flight control problem is formulated as a robust model tracking control problem. And then, based on the robust parametric approach, eigenstructure assignment and reference model tracking theory, a parametric optimization method for robust controller design is presented. The simulation results show the effectiveness of the proposed approach. 展开更多
关键词 hypersonic cruise vehicle robust parametric approach tracking control eigenstructure assignment parameter optimization
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Communication security of autonomous ground vehicles based on networked control systems:The optimized LMI approach 被引量:1
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作者 Xiao Cai Kaibo Shi +3 位作者 Kun She Shouming Zhong Shiping Wen Yuanlun Xie 《Security and Safety》 2023年第4期19-33,共15页
The paper presents a study of networked control systems(NCSs)that are subjected to periodic denial-of-service(DoS)attacks of varying intensity.The use of appropriate Lyapunov-Krasovskii functionals(LKFs)help to reduce... The paper presents a study of networked control systems(NCSs)that are subjected to periodic denial-of-service(DoS)attacks of varying intensity.The use of appropriate Lyapunov-Krasovskii functionals(LKFs)help to reduce the constraints of the basic conditions and lower the conservatism of the criteria.An optimization problem with constraints is formulated to select the trigger threshold,which is solved using the gradient descent algorithm(GDA)to improve resource utilization.An intelligent secure event-triggered controller(ISETC)is designed to ensure the safe operation of the system under DoS attacks.The approach is validated through experiments with an autonomous ground vehicle(AGV)system based on the Simulink platform.The proposed method offers the potential for developing effective defense mechanisms against DoS attacks in NCSs. 展开更多
关键词 Networked control system autonomous ground vehicle cyber security optimized LMI approach event-trigger control
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Signal processing method for shear wave velocity measurement 被引量:2
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作者 侯兴民 曲淑英 时向东 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期205-212,共8页
Soil shear wave velocity (SWV) is an important parameter in geotechnical engineering. To measure the soil SWV, three methods are generally used in China, including the single-hole method, cross-hole method and the s... Soil shear wave velocity (SWV) is an important parameter in geotechnical engineering. To measure the soil SWV, three methods are generally used in China, including the single-hole method, cross-hole method and the surface-wave technique. An optimized approach based on a correlation function for single-hole SWV measurement is presented in this paper. In this approach, inherent inconsistencies of the artificial methods such as negative velocities, and too-large and too-small velocities, are eliminated from the single-hole method, and the efficiency of data processing is improved. In addition, verification using the cross-hole method of upper measuring points shows that the proposed optimized approach yields high precision in signal processing. 展开更多
关键词 shear wave velocity single-hole method correlation function optimized approach
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Optimal Design of Equivalent Water Depth Truncated Mooring System Based on Baton Pattern Simulated Annealing Algorithm 被引量:3
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作者 张火明 黄赛花 管卫兵 《China Ocean Engineering》 SCIE EI CSCD 2014年第1期67-80,共14页
The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics ... The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics of the representative single mooring line between the truncated and full depth system are obtained by annealing simulation algorithm for hybrid discrete variables (ASFHDV, in short). A“baton” optimization approach is proposed by utilizing ASFHDV. After each baton of optimization, if a few dimensional variables reach the upper or lower limit, the boundary of certain dimensional variables shall be expanded. In consideration of the experimental requirements, the length of the upper mooring line should not be smaller than 8 m, and the diameter of the anchor chain on the bottom should be larger than 0.03 m. A 100000 t turret mooring FPSO in the water depth of 304 m, with the truncated water depth being 76 m, is taken as an example of equivalent water depth truncated mooring system optimal design and calculation, and is performed to obtain the conformation parameters of the truncated mooring system. The numerical results indicate that the present truncated mooring system design is successful and effective. 展开更多
关键词 hybrid model testing deep sea platforms equivalent water depth truncation FPSO optimization design baton optimization approach
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Review of JONSWAP Spectrum Based on Storm 149 from North Alwyn 被引量:3
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作者 徐继文 赫亮 王言英 《海洋工程:英文版》 2003年第2期283-288,共6页
The measured spectrum for Storm 149 from North Alwyn is calculated by use of FFT (Fast Fourier Transformation) arithmetic and its statistical characteristics are used to determine the predicted spectrum in which the J... The measured spectrum for Storm 149 from North Alwyn is calculated by use of FFT (Fast Fourier Transformation) arithmetic and its statistical characteristics are used to determine the predicted spectrum in which the JONSWAP formula is adopted to review comparative object. It is shown that the agreement between measured and predicted spectrum is satisfactory and some corrections to the parameters for the JONSWAP formula are necessary. 展开更多
关键词 wave spectrum FFT arithmetic statistical analysis optimizing approach
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Fault detection and optimization for networked control systems with uncertain time-varying delay 被引量:2
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作者 Qing Wang Zhaolei Wang +1 位作者 Chaoyang Dong Erzhuo Niu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期544-556,共13页
The observer-based robust fault detection filter design and optimization for networked control systems (NOSs) with uncer- tain time-varying delays are addressed. The NCSs with uncertain time-varying delays are model... The observer-based robust fault detection filter design and optimization for networked control systems (NOSs) with uncer- tain time-varying delays are addressed. The NCSs with uncertain time-varying delays are modeled as parameter-uncertain systems by the matrix theory. Based on the model, an observer-based residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of the linear matrix inequality. Furthermore, a time domain opti- mization approach is proposed to improve the performance of the fault detection system. To prevent the false alarms, a new thresh- old function is established, and the solution of the optimization problem is given by using the singular value decomposition (SVD) of the matrix. A numerical example is provided to illustrate the effectiveness of the proposed approach. 展开更多
关键词 fault detection networked control systems residual generator time-varying delay time domain optimization approach.
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Optimal paths planning in dynamic transportation networks with random link travel times 被引量:3
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作者 孙世超 段征宇 杨东援 《Journal of Central South University》 SCIE EI CAS 2014年第4期1616-1623,共8页
A theoretical study was conducted on finding optimal paths in transportation networks where link travel times were stochastic and time-dependent(STD). The methodology of relative robust optimization was applied as mea... A theoretical study was conducted on finding optimal paths in transportation networks where link travel times were stochastic and time-dependent(STD). The methodology of relative robust optimization was applied as measures for comparing time-varying, random path travel times for a priori optimization. In accordance with the situation in real world, a stochastic consistent condition was provided for the STD networks and under this condition, a mathematical proof was given that the STD robust optimal path problem can be simplified into a minimum problem in specific time-dependent networks. A label setting algorithm was designed and tested to find travelers' robust optimal path in a sampled STD network with computation complexity of O(n2+n·m). The validity of the robust approach and the designed algorithm were confirmed in the computational tests. Compared with conventional probability approach, the proposed approach is simple and efficient, and also has a good application prospect in navigation system. 展开更多
关键词 min-max relative regret approach robust optimal path problem stochastic time-dependent transportation networks stochastic consistent condition
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On Advanced Control Methods toward Power Capture and Load Mitigation in Wind Turbines 被引量:2
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作者 Yuan Yuan Jiong Tang 《Engineering》 SCIE EI 2017年第4期494-503,共10页
This article provides a survey of recently emerged methods for wind turbine control. Multivariate control approaches to the optimization of power capture and the reduction of loads in components under time-varying tur... This article provides a survey of recently emerged methods for wind turbine control. Multivariate control approaches to the optimization of power capture and the reduction of loads in components under time-varying turbulent wind fields have been under extensive investigation in recent years. We divide the related research activities into three categories: modeling and dynamics of wind turbines, active control of wind turbines, and passive control of wind turbines. Regarding turbine dynamics, we discuss the physical fundamentals and present the aeroelastic analysis tools. Regarding active control, we review pitch control, torque control, and yaw control strategies encompassing mathematical formulations as well as their applications toward different objectives. Our survey mostly focuses on blade pitch control, which is considered one of the key elements in facilitating load reduction while maintaining power capture performance. Regarding passive control, we review techniques such as tuned mass dampers, smart rotors, and microtabs. Possible future directions are suggested. 展开更多
关键词 Wind turbine Control approach Power optimization Load mitigation
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Extraction of optical constants and thickness of nanometre scale TiO2 film
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作者 杨莺歌 刘丕均 +1 位作者 王英 张亚非 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第11期2335-2337,共3页
TiO2 thin films were deposited on glass substrates by sputtering in a conventional rf magnetron sputtering system. X-ray diffraction pattern and transmission spectrum were measured. The curves of refraction index and ... TiO2 thin films were deposited on glass substrates by sputtering in a conventional rf magnetron sputtering system. X-ray diffraction pattern and transmission spectrum were measured. The curves of refraction index and extinction coefficient distributions as well as the thickness of films calculated from transmission spectrum were obtained. The optimization problem was also solved using a method based on a constrained nonlinear programming algorithm. 展开更多
关键词 TiO2 thin films pointwise constrained optimization approach constrained nonlinear programming optical constants parameters extraction
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ON APPROXIMATE EFFICIENCY FOR NONSMOOTH ROBUST VECTOR OPTIMIZATION PROBLEMS
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作者 Tadeusz ANTCZAK Yogendra PANDEY +1 位作者 Vinay SINGH Shashi Kant MISHRA 《Acta Mathematica Scientia》 SCIE CSCD 2020年第3期887-902,共16页
In this article,we use the robust optimization approach(also called the worst-case approach)for findingε-efficient solutions of the robust multiobjective optimization problem defined as a robust(worst-case)counterpar... In this article,we use the robust optimization approach(also called the worst-case approach)for findingε-efficient solutions of the robust multiobjective optimization problem defined as a robust(worst-case)counterpart for the considered nonsmooth multiobjective programming problem with the uncertainty in both the objective and constraint functions.Namely,we establish both necessary and sufficient optimality conditions for a feasible solution to be anε-efficient solution(an approximate efficient solution)of the considered robust multiobjective optimization problem.We also use a scalarizing method in proving these optimality conditions. 展开更多
关键词 Robust optimization approach robust multiobjective optimization ε-efficient solution ε-optimality conditions SCALARIZATION
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Structural-acoustic topology optimization analysis based on evolutionary structural optimization approach 被引量:1
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作者 CHEN Luyun WANG Deyu (State Key Laboratory of Ocean Eng.,Shanghai Jiao Tong University Shanghai 200030) 《Chinese Journal of Acoustics》 2009年第4期332-342,共11页
The continuum structural-acoustic topology optimization with external loading is investigated herein. Finite element method (FEM) is used to obtain the structural frequency response and boundary element method (BEM... The continuum structural-acoustic topology optimization with external loading is investigated herein. Finite element method (FEM) is used to obtain the structural frequency response and boundary element method (BEM) is adopted to perform exterior acoustic radiation analysis. The evolutionary structural optimization (ESO) is served as an optimization method in structural-acoustic radiation topology analysis. The acoustic radiation optimization of a plate under harmonic excitation is given for example. The numerical results show that using ESO solution to analyze structural-acoustic topology optimization is feasible and effective. 展开更多
关键词 ESO Structural-acoustic topology optimization analysis based on evolutionary structural optimization approach
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Optimization of a Segmented Filter with a New Error Diffusion Approach
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作者 Ayman Al Falou Marwa ELBouz 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期853-854,共2页
The segmented filters, based on spectral cutting, proved their efficiency for the multi-correlation. In this article we propose an optimisation of this cutting according to a new error diffusion method.
关键词 of on in with Optimization of a Segmented Filter with a New Error Diffusion approach for
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An improved equivalent beam model of large periodic beam-like space truss structures
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作者 Dongfang ZHU Xiaoxuan YAN +2 位作者 Jun SUN Fucheng LIU Dongxing CAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第12期297-308,共12页
Space truss structures are essential components for space-based remote sensing loads with high spatial and temporal resolutions.To achieve high-precision vibration control,an accurate and efficient dynamics model is e... Space truss structures are essential components for space-based remote sensing loads with high spatial and temporal resolutions.To achieve high-precision vibration control,an accurate and efficient dynamics model is essential.In addition to the current equivalent beam model(EBM)based on the classical continuum theory,an improved equivalent beam model(IEBM)is proposed that considers the impact of the distinction between trusses and beams on torsional and shear deformations,as well as the impact of shear deformation on flexural rigidity.According to the displacement expressions of spatial beams,torsional,shear,and bending correction coefficients are introduced to derive expressions of strain energy and kinetic energy.The energy equivalence principle is then utilized to calculate the elasticity and inertia matrices,and dynamics equations are established using the finite element method.Subsequently,an IEBM is constructed by employing the particle swarm optimization approach to determine the correction coefficients with the truss natural frequency as the optimization target.The natural vibration characteristics of the structure are estimated for various material properties.Compared with the full-scale finite element model,the EBM reaches a maximum error of 80%for a low modulus of elasticity,while the maximum error of the IEBM is less than 2%for any given parameters,indicating its superior accuracy to the EBM. 展开更多
关键词 Energy equivalence principle Improved equivalent beam model(IEBM) Natural vibration characteristic Particle swarm optimization approach Truss structure
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A Gradient-Based Optimization Method for the Design of Layered Phononic Band-Gap Materials 被引量:8
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作者 Yu Huang Shutian Liu Jian Zhao 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2016年第4期429-443,共15页
Phononic materials with specific band-gap characteristics at desired frequency ranges are in great demand for vibration and noise isolation, elastic wave filters, and acoustic devices. The attenuation coefficient curv... Phononic materials with specific band-gap characteristics at desired frequency ranges are in great demand for vibration and noise isolation, elastic wave filters, and acoustic devices. The attenuation coefficient curve depicts both the frequency range of band gap and the attenuation of elastic wave, where the frequency ranges corresponding to the none-zero attenuation coefficients are band gaps. Therefore, the band-gap characteristics can be achieved through maximizing the attenuation coefficient at the corresponding frequency or within the corresponding frequency range. Because the attenuation coefficient curve is not smooth in the frequency domain, the gradient-based optimization methods cannot be directly used in the design optimization of phononic band-gap materials to achieve the maximum attenuation within the desired frequency range. To overcome this difficulty, the objective of maximizing the attenuation coefficient is transformed into maximizing its Cosine, and in this way, the objective function is smoothed and becomes differentiable. Based on this objective function, a novel gradient-based optimization approach is proposed to open the band gap at a prescribed frequency range and to further maximize the attenuation efficiency of the elastic wave at a specific frequency or within a prescribed frequency range. Numerical results demonstrate the effectiveness of the proposed gradient-based optimization method for enhancing the wave attenuation properties. 展开更多
关键词 OPTIMIZATION band gap gradient-based optimization two-step optimization approach
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Estimation of hydraulic parameters from pumping tests in a multiaquifer system 被引量:2
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作者 Da Ha Gang Zheng +2 位作者 Haizuo Zhou Chaofeng Zeng Huihui Zhang 《Underground Space》 SCIE EI 2020年第3期210-222,共13页
The hydrogeologic conditions in Tianjin,China,are characterized by a system of multiple alternating aquifers and aquitards and a high groundwater level.Generally,the groundwater system to a depth of 70 m includes one ... The hydrogeologic conditions in Tianjin,China,are characterized by a system of multiple alternating aquifers and aquitards and a high groundwater level.Generally,the groundwater system to a depth of 70 m includes one phreatic aquifer and three semiconfined aquifers(AqI–AqIII).The distribution of aquifers varies greatly.Accurate estimates of aquifer parameters from pumping tests are essential in geotechnical engineering practice.In this study,the applicability of different models for estimating hydraulic parameters in a multiaquifer system is analyzed.To avoid errors in the graphic-analytical process and to enhance the efficiency and accuracy,a hybrid algorithm,called GALMA(a genetic algorithm(GA)combined with the Levenberg–Marquardt(LM)algorithm),is used with the Neuman and Witherspoon model and ratio method.The estimated values in the second and third semiconfined aquifers(AqII and AqIII)from various solutions are compared with the measured data.Further validations based on the prediction of the drawdown values are performed via a three dimensional numerical simulation. 展开更多
关键词 Hydraulic parameter Leaky aquifer Pumping test Optimal approach
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Scheme-scale ambiguity in analysis of QCD observable
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作者 A.Mirjalili B.A.Kniehl 《Chinese Physics C》 SCIE CAS CSCD 2010年第9期1523-1526,共4页
The scheme-scale ambiguity that has plagued perturbative analysis in QCD remains on obstacle to making precise tests of the theory.Many attempts have been done to resolve the scale ambiguity.In this regard the BLM,EC,... The scheme-scale ambiguity that has plagued perturbative analysis in QCD remains on obstacle to making precise tests of the theory.Many attempts have been done to resolve the scale ambiguity.In this regard the BLM,EC,PMS and CORGI approaches are more distinct.We try to employ these methods to fix the scale ambiguity at NLO,NNLO and even in more higher order approximations.By optimizing the renormalization scale,there will be a possibility to predicate higher order terms.We present general results for predicted terms at any order,using different optimization methods.Some observable as specific examples will be used to indicate the validity of scale fixing to predicate the higher order terms. 展开更多
关键词 perturbative QCD scheme and scale dependence optimization approach predicted terms
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