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A Novel Reliable and Trust Objective Function for RPL-Based IoT Routing Protocol
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作者 Mariam A.Alotaibi Sami S.Alwakeel Aasem N.Alyahya 《Computers, Materials & Continua》 2025年第2期3467-3497,共31页
The Internet of Things (IoT) integrates diverse devices into the Internet infrastructure, including sensors, meters, and wearable devices. Designing efficient IoT networks with these heterogeneous devices requires the... The Internet of Things (IoT) integrates diverse devices into the Internet infrastructure, including sensors, meters, and wearable devices. Designing efficient IoT networks with these heterogeneous devices requires the selection of appropriate routing protocols, which is crucial for maintaining high Quality of Service (QoS). The Internet Engineering Task Force’s Routing Over Low Power and Lossy Networks (IETF ROLL) working group developed the IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) to meet these needs. While the initial RPL standard focused on single-metric route selection, ongoing research explores enhancing RPL by incorporating multiple routing metrics and developing new Objective Functions (OFs). This paper introduces a novel Objective Function (OF), the Reliable and Secure Objective Function (RSOF), designed to enhance the reliability and trustworthiness of parent selection at both the node and link levels within IoT and RPL routing protocols. The RSOF employs an adaptive parent node selection mechanism that incorporates multiple metrics, including Residual Energy (RE), Expected Transmission Count (ETX), Extended RPL Node Trustworthiness (ERNT), and a novel metric that measures node failure rate (NFR). In this mechanism, nodes with a high NFR are excluded from the parent selection process to improve network reliability and stability. The proposed RSOF was evaluated using random and grid topologies in the Cooja Simulator, with tests conducted across small, medium, and large-scale networks to examine the impact of varying node densities. The simulation results indicate a significant improvement in network performance, particularly in terms of average latency, packet acknowledgment ratio (PAR), packet delivery ratio (PDR), and Control Message Overhead (CMO), compared to the standard Minimum Rank with Hysteresis Objective Function (MRHOF). 展开更多
关键词 IOT LLNs RPL objective function OF MRHOF OF0 routing metrics RELIABILITY trustworthiness
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OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:5
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作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
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Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm 被引量:4
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作者 Qi-Hong Feng Shan-Shan Li +2 位作者 Xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2879-2894,共16页
Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.T... Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development. 展开更多
关键词 Well production Optimization efficiency Streamline simulation Streamline feature objective function Bayesian adaptive direct search algorithm
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Reactor Network Synthesis Based on Instantaneous Objective Function Characteristic Curves 被引量:2
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作者 张治山 赵文 +2 位作者 王艳丽 周传光 袁希钢 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第4期436-440,共5页
It is believed that whether the instantaneous objective function curves of plug-flow-reactor (PFR) and continuous-stirred-tank-reactor (CSTR) overlap or not, they have a consistent changing trend for complex reactions... It is believed that whether the instantaneous objective function curves of plug-flow-reactor (PFR) and continuous-stirred-tank-reactor (CSTR) overlap or not, they have a consistent changing trend for complex reactions (steady state, isothermal and constant volume). As a result of the relation of the objective functions (selectivity or yield) to the instantaneous objective functions (instantaneous selectivity or instantaneous reaction rate), the optimal reactor network configuration can be determined according to the changing trend of the instantaneous objective function curves. Further, a recent partition strategy for the reactor network synthesis based on the instantaneous objective function characteristic curves is proposed by extending the attainable region partition strategy from the concentration space to the instantaneous objective function-unreacted fraction of key reactant space. In this paper, the instantaneous objective function is closed to be the instantaneous selectivity and several samples are examined to illustrate the proposed method. The comparison with the previous work indicates it is a very convenient and practical systematic tool of the reactor network synthesis and seems also promising for overcoming the dimension limit of the attainable region partition strategy in the concentration space. 展开更多
关键词 reactor network synthesis instantaneous objective function PARTITION
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SELECTION OF OBJECTIVE FUNCTIONS AND APPLICATION OF GENETIC ALGORITHMS IN DAMPING DESIGN OF PIPE SYSTEM 被引量:1
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作者 ChenYanqiu FanQinsban ZhuZigen 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第2期171-178,共8页
The vibration failure of pipe system of aeroengine seriously influences the safety of aircraft.Its damping design is determined by the selection of the design target,method and their feasibility.Five objective functio... The vibration failure of pipe system of aeroengine seriously influences the safety of aircraft.Its damping design is determined by the selection of the design target,method and their feasibility.Five objective functions for the vibration design of a pipeline or pipe system are introduced,namely,the frequency,amplitude,transfer ratio,curvature and deformation energy as options for the optimization process.The genetic algorithms(GA)are adopted as the opti- mization method,in which the selection of the adaptive genetic operators and the method of implementation of the GA process are crucial.The optimization procedure for all the above ob- jective functions is carried out using GA on the basis of finite element software-MSC/NASTRAN. The optimal solutions of these functions and the stress distribution on the structure are calculated and compared through an example,and their characteristics are analyzed.Finally we put forward two new objective functions,curvature and deformation energy for pipe system optimization.The calculations show that using the curvature as the objective function can reflect the case of minimal stress,and the optimization results using the deformation energy represent lesser and more uni- form stress distribution.The calculation results and process showed that the genetic algorithms can effectively implement damping design of engine pipelines and satisfy the efficient engineering design requirement. 展开更多
关键词 objective function genetic algorithms OPTIMIZATION pipe system
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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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FUZZY IDENTIFICATION METHOD BASED ON A NEW OBJECTIVE FUNCTION
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作者 王宏伟 贺汉根 黄柯棣 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第3期162-166,共5页
A method of fuzzy identification based on a new objective function is proposed. The method could deal with the issue that input variables of a system have an effect on the input space while output variables of the sys... A method of fuzzy identification based on a new objective function is proposed. The method could deal with the issue that input variables of a system have an effect on the input space while output variables of the system do not exert an influence on the input space in the proposed objective functions of fuzzy clustering. The method could simultaneously solve the problems about structure identification and parameter estimation; thus it makes the fuzzy model become optimal. Simulation example demonstrates that the method could identify non linear systems and obviously improve modeling accuracy. 展开更多
关键词 objective function fuzzy clustering fuzzy identification non linear systems
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Experimental Evaluation of Objective Functions for Well-balanced Mapping
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作者 Chen Delai Xu Hong Zhou Ying and Zhang Defu(Department of Computer Science and Technology Nailing University, Naming 210093, P. R. China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期312-316,共5页
High performance of parallel computing on a message-passing multicomputer System relies on the balance of the workloads located on the processing elements of the System and the minimum communication ovcrheads among th... High performance of parallel computing on a message-passing multicomputer System relies on the balance of the workloads located on the processing elements of the System and the minimum communication ovcrheads among them. Mapping is the technology to partition the problem domain wellbalanced into multiple distinct execution tasks based on some measures. In mapping, a good objective function is the criterion to guarantce the distinct execution tasks equitable. In this paper, we evaluate five categories of those existed objective functions with three different problem subjects using experiments and find an objective function is much suitable for all kinds of problems. 展开更多
关键词 MAPPING Heuristic algorithm objective functions
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Searching for an Optimized Single-objective Function Matching Multiple Objectives with Automatic Calibration of Hydrological Models
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作者 TIAN Fuqiang HU Hongchang +2 位作者 SUN Yu LI Hongyi LU Hui 《Chinese Geographical Science》 SCIE CSCD 2019年第6期934-948,共15页
In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies,... In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies, there is a general opinion that no single-objective function can represent all important characteristics of even one specific hydrological variable(e.g., streamflow).Thus hydrologists must turn to multi-objective calibration.In this study, we demonstrated that an optimized single-objective function can compromise multi-response modes(i.e., multi-objective functions) of the hydrograph, which is defined as summation of a power function of the absolute error between observed and simulated streamflow with the exponent of power function optimized for specific watersheds.The new objective function was applied to 196 model parameter estimation experiment(MOPEX) watersheds across the eastern United States using the semi-distributed Xinanjiang hydrological model.The optimized exponent value for each watershed was obtained by targeting four popular objective functions focusing on peak flows, low flows, water balance, and flashiness, respectively.Results showed that the optimized single-objective function can achieve a better hydrograph simulation compared to the traditional single-objective function Nash-Sutcliffe efficiency coefficient for most watersheds, and balance high flow part and low flow part of the hydrograph without substantial differences compared to multi-objective calibration.The proposed optimal single-objective function can be practically adopted in the hydrological modeling if the optimal exponent value could be determined a priori according to hydrological/climatic/landscape characteristics in a specific watershed. 展开更多
关键词 automatic calibration single-objective function MULTI-objectIVE functions Xinanjiang MODEL HYDROLOGICAL MODEL
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Randomized Objective Function Linear Programming in Risk Management
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作者 Dennis Ridley Felipe Llaugel +1 位作者 Inger Daniels Abdullah Khan 《Journal of Applied Mathematics and Physics》 2021年第3期391-402,共12页
The traditional linear programming model is deterministic. The way that uncertainty is handled is to compute the range of optimality. After the optimal solution is obtained, typically by the simplex method, one consid... The traditional linear programming model is deterministic. The way that uncertainty is handled is to compute the range of optimality. After the optimal solution is obtained, typically by the simplex method, one considers the effect of varying each objective function coefficient, one at a time. This yields the range of optimality within which the decision variables remain constant. This sensitivity analysis is useful for helping the analyst get a sense for the problem. However, it is unrealistic because objective function coefficients tend not to stand still. They are typically profit contributions from products sold and are subject to randomly varying selling prices. In this paper, a realistic linear program is created for simultaneously randomizing the coefficients from any probability distribution. Furthermore, we present a novel approach for designing a copula of random objective function coefficients according to a specified rank correlation. The corresponding distribution of objective function values is created. This distribution is examined directly for central tendency, spread, skewness and extreme values for the purpose of risk analysis. This enables risk analysis and business analytics, emerging topics in education and preparation for the knowledge economy. 展开更多
关键词 Linear Programming RANDOM objective function Profit Distribution RISK Monte Carlo Simulation
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Adaptive Learning Rate Optimization BP Algorithm with Logarithmic Objective Function
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作者 李春雨 盛昭瀚 《Journal of Southeast University(English Edition)》 EI CAS 1997年第1期47-51,共5页
This paper presents an improved BP algorithm. The approach can reduce the amount of computation by using the logarithmic objective function. The learning rate μ(k) per iteration is determined by dynamic o... This paper presents an improved BP algorithm. The approach can reduce the amount of computation by using the logarithmic objective function. The learning rate μ(k) per iteration is determined by dynamic optimization method to accelerate the convergence rate. Since the determination of the learning rate in the proposed BP algorithm only uses the obtained first order derivatives in standard BP algorithm(SBP), the scale of computational and storage burden is like that of SBP algorithm,and the convergence rate is remarkably accelerated. Computer simulations demonstrate the effectiveness of the proposed algorithm 展开更多
关键词 BP ALGORITHM ADAPTIVE LEARNING RATE optimization fault diagnosis logarithmic objective function
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A New Augmented Lagrangian Objective Penalty Function for Constrained Optimization Problems
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作者 Ying Zheng Zhiqing Meng 《Open Journal of Optimization》 2017年第2期39-46,共8页
In this paper, a new augmented Lagrangian penalty function for constrained optimization problems is studied. The dual properties of the augmented Lagrangian objective penalty function for constrained optimization prob... In this paper, a new augmented Lagrangian penalty function for constrained optimization problems is studied. The dual properties of the augmented Lagrangian objective penalty function for constrained optimization problems are proved. Under some conditions, the saddle point of the augmented Lagrangian objective penalty function satisfies the first-order Karush-Kuhn-Tucker (KKT) condition. Especially, when the KKT condition holds for convex programming its saddle point exists. Based on the augmented Lagrangian objective penalty function, an algorithm is developed for finding a global solution to an inequality constrained optimization problem and its global convergence is also proved under some conditions. 展开更多
关键词 CONSTRAINED Optimization Problems AUGMENTED LAGRANGIAN objective PENALTY function SADDLE POINT Algorithm
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A Penalty Function Algorithm with Objective Parameters and Constraint Penalty Parameter for Multi-Objective Programming
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作者 Zhiqing Meng Rui Shen Min Jiang 《American Journal of Operations Research》 2014年第6期331-339,共9页
In this paper, we present an algorithm to solve the inequality constrained multi-objective programming (MP) by using a penalty function with objective parameters and constraint penalty parameter. First, the penalty fu... In this paper, we present an algorithm to solve the inequality constrained multi-objective programming (MP) by using a penalty function with objective parameters and constraint penalty parameter. First, the penalty function with objective parameters and constraint penalty parameter for MP and the corresponding unconstraint penalty optimization problem (UPOP) is defined. Under some conditions, a Pareto efficient solution (or a weakly-efficient solution) to UPOP is proved to be a Pareto efficient solution (or a weakly-efficient solution) to MP. The penalty function is proved to be exact under a stable condition. Then, we design an algorithm to solve MP and prove its convergence. Finally, numerical examples show that the algorithm may help decision makers to find a satisfactory solution to MP. 展开更多
关键词 MULTI-objectIVE Programming PENALTY function objective PARAMETERS CONSTRAINT PENALTY Parameter PARETO Weakly-Efficient Solution
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An Objective Penalty Functions Algorithm for Multiobjective Optimization Problem
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作者 Zhiqing Meng Rui Shen Min Jiang 《American Journal of Operations Research》 2011年第4期229-235,共7页
By using the penalty function method with objective parameters, the paper presents an interactive algorithm to solve the inequality constrained multi-objective programming (MP). The MP is transformed into a single obj... By using the penalty function method with objective parameters, the paper presents an interactive algorithm to solve the inequality constrained multi-objective programming (MP). The MP is transformed into a single objective optimal problem (SOOP) with inequality constrains;and it is proved that, under some conditions, an optimal solution to SOOP is a Pareto efficient solution to MP. Then, an interactive algorithm of MP is designed accordingly. Numerical examples show that the algorithm can find a satisfactory solution to MP with objective weight value adjusted by decision maker. 展开更多
关键词 MULTIobjectIVE Optimization PROBLEM objective PENALTY function PARETO Efficient Solution INTERACTIVE ALGORITHM
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VECTOR WAVE FUNCTION EXPANSION FOR SOLVING ELECTROMAGNETIC SCATTERING BY BURIED OBJECTS
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作者 陈景养 徐鹏根 鲁述 《Journal of Electronics(China)》 1991年第3期239-246,共8页
An analysis of solving the electromagnetic scattering by buried objects using vectorwave function expansion is presented.For expanding the boundary conditions both on the planarair-earth interface and on the spherical... An analysis of solving the electromagnetic scattering by buried objects using vectorwave function expansion is presented.For expanding the boundary conditions both on the planarair-earth interface and on the spherical surface,the conversion relations between the cylindricaland spherical vector wave functions are derived.Hence the vector wave function expansion isconveniently applied to solve this complex boundary-value problem.For the excitation of the in-cident plane wave and the dipole above the earth,the scatterlng patterns of the buried conductingand dielectric spheres are presented and discussed. 展开更多
关键词 Electromagnetic scattering BURIED objects Boundary condition VECTOR WAVE function EXPANSION WAVE transformation
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Multi-objective optimization about functions of the East Lake in Wuhan
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作者 LI Xin-min LI Rong 《汉口学院学报》 2009年第3期49-52,共4页
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Optimality for Multi-Objective Programming Involving Arcwise Connected d-Type-I Functions
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作者 Guolin Yu Min Wang 《American Journal of Operations Research》 2011年第4期243-248,共6页
This paper deals with the optimality conditions and dual theory of multi-objective programming problems involving generalized convexity. New classes of generalized type-I functions are introduced for arcwise connected... This paper deals with the optimality conditions and dual theory of multi-objective programming problems involving generalized convexity. New classes of generalized type-I functions are introduced for arcwise connected functions, and examples are given to show the existence of these functions. By utilizing the new concepts, several sufficient optimality conditions and Mond-Weir type duality results are proposed for non-differentiable multi-objective programming problem. 展开更多
关键词 Multi-objective Programming Pareto Efficient Solution Arcwise Connected d-Type-I functionS OPTIMALITY Conditions Duality
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基于多尺度特征增强的航拍小目标检测算法
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作者 肖剑 何昕泽 +2 位作者 程鸿亮 杨小苑 胡欣 《浙江大学学报(工学版)》 北大核心 2026年第1期19-31,共13页
针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强... 针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强对小目标细粒度特征的捕获;基于PAN-FPN架构调整特征融合网络,增加对浅层特征的关注,同时引入多尺度卷积核增强对目标上下文信息的关注,以适应小目标检测场景;针对传统IoU灵活性、泛化性不强的问题,构建参数可调的Nin-IoU,通过引入可调参数,实现对IoU的针对性调整,以适应不同检测任务的需求;提出轻量化检测头,在增强多尺度特征信息交融的同时减少冗余信息的传递.结果表明,在VisDrone2019数据集上,所提算法以8.08×106的参数量实现了mAP0.5=50.3%的检测精度;相较于基准算法YOLOv8s,参数量降低了27.4%,精度提升了11.5个百分点.在DOTA与DIOR数据集上的实验结果表明,所提算法具有较强的泛化能力. 展开更多
关键词 目标检测 YOLOv8 无人机图像 特征融合 损失函数
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基于Supermap Objects的区域生态环境监测鹰眼功能的实现 被引量:4
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作者 韩松 马民涛 +2 位作者 张雁雁 王江萍 张菁 《江苏环境科技》 2007年第6期54-55,共2页
介绍了以Supermap Objects为基础开发的用于城市生态监测的地理信息系统的空间信息查询鹰眼功能可研究开发及实现。
关键词 区域生态环境 地理信息系统 SUPERMAP objectS 鹰眼功能
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英语“V+ing+Object”结构的功能语法分析 被引量:1
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作者 张殿恩 《长江师范学院学报》 2011年第4期68-71,159,共4页
在传统英语语法中,因为"V+ing+Object"结构在句子中所起的语法作用不同,该结构被划分为"动名词短语"、"分词结构"或"ing分词短语"。文章以系统功能语法体系为指导,从意义的角度对该结构进行功... 在传统英语语法中,因为"V+ing+Object"结构在句子中所起的语法作用不同,该结构被划分为"动名词短语"、"分词结构"或"ing分词短语"。文章以系统功能语法体系为指导,从意义的角度对该结构进行功能分析。文章的讨论与分析表明英语的"V+ing+Object"结构归为动宾结构小句,胜过划分为一般语法所划分的"动名词短语"、"分词短语"或"ing分词短语"。 展开更多
关键词 动词+ing+宾语 功能语法 英语语法
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