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Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network
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作者 YANG Luyi LI Haiyang +1 位作者 ZHANG Jin ZHU Yuehe 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期495-508,共14页
It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval... It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model. 展开更多
关键词 manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency
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Error reachable set based stabilization of switched linear systems with bounded peak disturbances
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作者 Xinxin Shang Songlin Zhuang +1 位作者 Tianyu Tan Yang Shi 《Journal of Automation and Intelligence》 2023年第2期87-98,共12页
This paper investigates the error reachable set based stabilization problem for a class of discrete-time switched linear systems with bounded peak disturbances under persistent dwell-time(PDT)constraint.A double-clock... This paper investigates the error reachable set based stabilization problem for a class of discrete-time switched linear systems with bounded peak disturbances under persistent dwell-time(PDT)constraint.A double-clockdependent control scheme is presented that can split the disturbed switched system into a nominal system and an error system,and assign to each system a controller scheduled by a clock.A necessary and sufficient convex stability criterion is presented for the nominal system,and is further extended to the stabilization controller design with a nominal clock.In the presence of bounded peak disturbances,another stabilization controller with an error clock is developed for the error system,with the purpose of‘‘minimizing’’the reachable set of the error system by the ellipsoidal techniques.It is demonstrated that the disturbed system is also globally exponentially stable in the sense of converging to an over approximation of the reachable set of the error system,i.e.,a union of a family of bounding ellipsoids,that can also be regarded as the cross section of a tube containing the trajectories of the disturbed system.Two numerical examples are provided to verify the effectiveness of the developed results. 展开更多
关键词 Bounded peak disturbances Persistent dwell-time reachable set minimization Stability and stabilization Switched systems
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Reachable set estimation for discrete-time Markovian jump neural networks with unified uncertain transition probability
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作者 Yufeng Tian Wengang Ao Peng Shi 《Journal of Automation and Intelligence》 2023年第3期167-174,共8页
This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism... This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism of these systems.To fully exploit the unified uncertain transition probabilities,an equivalent transformation technique is introduced as an alternative to traditional estimation methods,effectively utilizing the information of transition probabilities.Furthermore,a vector Wirtinger-based summation inequality is proposed,which captures more system information compared to existing ones.Building upon these components,a novel condition that guarantees a reachable set estimation is presented for Markovian jump neural networks with unified uncertain transition probabilities.A numerical example is illustrated to demonstrate the superiority of the approaches. 展开更多
关键词 Markovian jump neural networks Unified uncertain transition probabilities reachable set estimation Double-boundary approach Vector wirtinger-based summation inequality
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The No-Ellipsoidal Bound of Reachable Sets for Neutral Markovian Jump Systems with Disturbances
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作者 Changchun Shen Shouwei Zhou Hongyong Deng 《Journal of Applied Mathematics and Physics》 2020年第5期799-813,共15页
This paper is concerned with the reachable set estimation problem for neutral Markovian jump systems with bounded peak disturbances, which was rarely proposed for neutral Markovian jump systems. The main consideration... This paper is concerned with the reachable set estimation problem for neutral Markovian jump systems with bounded peak disturbances, which was rarely proposed for neutral Markovian jump systems. The main consideration is to find a proper method to obtain the no-ellipsoidal bound of the reachable set for neutral Markovian jump system as small as possible. By applying Lyapunov functional method, some derived conditions are obtained in the form of matrix inequalities. Finally, numerical examples are presented to demonstrate the effectiveness of the theoretical results. 展开更多
关键词 reachable Set No-Ellipsoidal BOUND LINEAR NEUTRAL System LYAPUNOV-KRASOVSKII LINEAR Matrix INEQUALITIES
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Computing Reachable Sets as Capture-Viability Kernels in Reverse Time
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作者 Noel Bonneuil 《Applied Mathematics》 2012年第11期1593-1597,共5页
The set SF(x0;T) of states y reachable from a given state x0 at time T under a set-valued dynamic x’(t)∈F(x (t)) and under constraints x(t)∈K where K is a closed set, is also the capture-viability kernel of x0 at T... The set SF(x0;T) of states y reachable from a given state x0 at time T under a set-valued dynamic x’(t)∈F(x (t)) and under constraints x(t)∈K where K is a closed set, is also the capture-viability kernel of x0 at T in reverse time of the target {x0} while remaining in K. In dimension up to three, Saint-Pierre’s viability algorithm is well-adapted;for higher dimensions, Bonneuil’s viability algorithm is better suited. It is used on a large-dimensional example. 展开更多
关键词 Set-Valued Analysis reachable Set
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Reachable set estimation for spacecraft relative motion based on bang-bang principle 被引量:1
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作者 Lizhen SHAO Haibin MIAO +1 位作者 Renhong HU Hongjin LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期229-240,共12页
For spacecraft formation flight,the information of relative motion reachable set is very important,which can be used to predict the operating boundary of adjacent spacecraft and thus to ensure the safety of spacecraft... For spacecraft formation flight,the information of relative motion reachable set is very important,which can be used to predict the operating boundary of adjacent spacecraft and thus to ensure the safety of spacecraft operation.In this paper,we aim at developing a numerical method to approximate the reachable set for spacecraft relative motion.In particular,we focus on the quality of the approximation and the computational cost.Based on the bang-bang control principle,a polyhedral approximation algorithm is proposed to compute the reachable set of a relative motion spacecraft system.An inner approximation and an outer approximation of the reachable set for the system can be obtained.We prove that the approximation quality measured in Hausdorff distance can be guaranteed.The method is easy to implement and has low computational cost.Finally,the effectiveness of the algorithm is demonstrated by experimental simulation. 展开更多
关键词 Polyhedral approximation reachable set Spacecraft control Spacecraft relative motion The bang-bang control principle
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Calculating collision probability for long-term satellite encounters through the reachable domain method 被引量:4
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作者 Changxuan Wen Dong Qiao 《Astrodynamics》 EI CSCD 2022年第2期141-159,共19页
ABSTRACT Satellite encounters during close operations,such as rendezvous,formation,and cluster flights,are typical long-term encounters.The collision probability in such an encounter is a primary safety concern.In thi... ABSTRACT Satellite encounters during close operations,such as rendezvous,formation,and cluster flights,are typical long-term encounters.The collision probability in such an encounter is a primary safety concern.In this study,a parametric method is proposed to compute the long-term collision probability for close satellite operations with initial state uncertainty.Random relative state errors resulting from system uncertainty lead to possible deviated trajectories with respect to the nominal one.To describe such a random event meaningfully,each deviated trajectory sample should be mapped to a unique and time-independent element in a random variable(RV)space.In this study,the RV space was identified as the transformed state space at a fixed initial time.The physical dimensions of both satellites were characterized by a combined hard-body sphere.Transforming the combined hard-body sphere into the RV space yielded a derived ellipsoid,which evolved over time and swept out a derived collision volume.The derived collision volume was solved using the reachable domain method.Finally,the collision probability was computed by integrating a probability density function over the derived collision volume.The results of the proposed method were compared with those of a nonparametric computation-intensive Monte Carlo method.The relative difference between the two results was found to be<0.6%,verifying the accuracy of the proposed method. 展开更多
关键词 close satellite operations uncertainty random variables collision volume long-term collision probability reachable domain
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Evolution of Specialization with Reachable Transaction Scope Based on a Simple and Symmetric Firm Resource Allocation Model 被引量:2
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作者 Xiao Sun Yueting Chai +2 位作者 Yi Liu Jianping Shen Yadong Huang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2017年第1期10-28,共19页
In the last decade, as an emerging transaction measure driven by computer and internet technology, e-commerce experienced explosive growth in many areas. It has greatly broken down the limitations of space and time to... In the last decade, as an emerging transaction measure driven by computer and internet technology, e-commerce experienced explosive growth in many areas. It has greatly broken down the limitations of space and time to economic activities, thus changing the rules of business fundamentally. Significant work has been done to understand the laws of e-commerce from multiple dimensions, but the question of how e-commerce shapes firms' specialization and market structure from the perspective of spatial factors remains obscure. In this paper, we propose a simple and symmetric firm resource allocation model with a specialized-economy production function and market size constraint, to investigate how individual firms adjust resource allocation with reachable transaction scope expanded. It is shown that with the expansion of reachable transaction scope, individual firms discretely take back one unit resource from a low-investment direction and, instead, channel it to a "specialized direction". Meanwhile, at the macro level, an optimal division network evolves from a static self-sufficient stage to a diverse semi-specialized stage, and finally to a highly integrated completely specialized stage. Ergo, a Complex Adaptive System (CAS) based simulation framework is constructed. Designed simulation experiments are carried out and confirm to the analysis result of our proposed model. 展开更多
关键词 E-COMMERCE EVOLUTION reachable transaction scope resource allocation complex adaptive system
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Reachable domain for spacecraft with ellipsoidal Delta-V distribution 被引量:5
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作者 Changxuan Wen Chao Peng Yang Gao 《Astrodynamics》 2018年第3期265-288,共24页
Conventional reachable domain(RD)problem with an admissible velocity increment,Δv,in an isotropic distribution,was extended to the general case withΔv in an anisotropic ellipsoidal distribution.Such an extension ena... Conventional reachable domain(RD)problem with an admissible velocity increment,Δv,in an isotropic distribution,was extended to the general case withΔv in an anisotropic ellipsoidal distribution.Such an extension enables RD to describe the effect of initial velocity uncertainty because a Gaussian form of velocity uncertainty can be regarded as possible velocity deviations that are confined within an error ellipsoid.To specify RD in space,the boundary surface of RD,also known as the envelope,should be determined.In this study,the envelope is divided into two parts:inner and outer envelopes.Thus,the problem of solving the RD envelope is formulated into an optimization problem.The inner and outer reachable boundaries that are closest to and farthest away from the center of the Earth,respectively,were found in each direction.An optimal control policy is then formulated by using the necessary condition for an optimum;that is,the first-order derivative of the performance function with respect to the control variable becomes zero.Mathematical properties regarding the optimal control policy is discussed.Finally,an algorithm to solve the RD envelope is proposed.In general,the proposed algorithm does not require any iteration,and therefore benefits from quick computation.Numerical examples,including two coplanar cases and two 3D cases,are provided,which demonstrate that the proposed algorithm works efficiently. 展开更多
关键词 reachable domain MANEUVERABILITY orbit uncertainty
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Reachability-Based Confidence-Aware Probabilistic Collision Detection in Highway Driving
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作者 Xinwei Wang Zirui Li +1 位作者 Javier Alonso-Mora Meng Wang 《Engineering》 SCIE EI CAS CSCD 2024年第2期90-107,共18页
Risk assessment is a crucial component of collision warning and avoidance systems for intelligent vehicles.Reachability-based formal approaches have been developed to ensure driving safety to accurately detect potenti... Risk assessment is a crucial component of collision warning and avoidance systems for intelligent vehicles.Reachability-based formal approaches have been developed to ensure driving safety to accurately detect potential vehicle collisions.However,they suffer from over-conservatism,potentially resulting in false–positive risk events in complicated real-world applications.In this paper,we combine two reachability analysis techniques,a backward reachable set(BRS)and a stochastic forward reachable set(FRS),and propose an integrated probabilistic collision–detection framework for highway driving.Within this framework,we can first use a BRS to formally check whether a two-vehicle interaction is safe;otherwise,a prediction-based stochastic FRS is employed to estimate the collision probability at each future time step.Thus,the framework can not only identify non-risky events with guaranteed safety but also provide accurate collision risk estimation in safety-critical events.To construct the stochastic FRS,we develop a neural network-based acceleration model for surrounding vehicles and further incorporate a confidence-aware dynamic belief to improve the prediction accuracy.Extensive experiments were conducted to validate the performance of the acceleration prediction model based on naturalistic highway driving data.The efficiency and effectiveness of the framework with infused confidence beliefs were tested in both naturalistic and simulated highway scenarios.The proposed risk assessment framework is promising for real-world applications. 展开更多
关键词 Probabilistic collision detection Confidence awareness Probabilistic acceleration prediction Reachability analysis Risk assessment
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Reachable set modeling and engagement analysis of exoatmospheric interceptor 被引量:1
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作者 Chai Hua Liang Yangang +1 位作者 Chen Lei Tang Guojin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1513-1526,共14页
A novel reachable set(RS) model is developed within a framework of exoatmospheric interceptor engagement analysis. The boost phase steering scheme and trajectory distortion mechanism of the interceptor are firstly e... A novel reachable set(RS) model is developed within a framework of exoatmospheric interceptor engagement analysis. The boost phase steering scheme and trajectory distortion mechanism of the interceptor are firstly explored. A mathematical model of the distorted RS is then formulated through a dimension–reduction analysis. By treating the outer boundary of the RS on sphere surface as a spherical convex hull, two relevant theorems are proposed and the RS envelope is depicted by the computational geometry theory. Based on RS model, the algorithms of intercept window analysis and launch parameters determination are proposed, and numerical simulations are carried out for interceptors with different energy or launch points. Results show that the proposed method can avoid intensive on-line computation and provide an accurate and effective approach for interceptor engagement analysis. The suggested RS model also serves as a ready reference to other related problems such as interceptor effectiveness evaluation and platform disposition. 展开更多
关键词 Engagement analysis Flight dynamics Interception reachable set Spherical convex hull
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Reachable Set Analysis for Dynamic Neural Networks with Polytopic Uncertainties
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作者 左志强 陈银萍 王一晶 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第5期904-908,共5页
In this paper,the reachable set estimation problem is studied for a class of dynamic neural networks subject to polytopic uncertainties.The problem addressed here is to find a set as small as possible to bound the sta... In this paper,the reachable set estimation problem is studied for a class of dynamic neural networks subject to polytopic uncertainties.The problem addressed here is to find a set as small as possible to bound the states starting from the origin by inputs with peak values.The maximal Lyapunov functional is proposed to derive a sufficient condition for the existence of a non-ellipsoidal bound to estimate the states of neural networks.It is theoretically shown that this method is superior to the traditional one based on the common Lyapunov function.Finally,two examples illustrate the advantages of our proposed result. 展开更多
关键词 neural networks reachable set polytopic uncertainties maximal Lyapunov functional
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Reachable Set Estimation and Safety Verification of Nonlinear Systems via Iterative Sums of Squares Programming
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作者 LIN Wang YANG Zhengfeng DING Zuohua 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2022年第3期1154-1172,共19页
In this paper,the problems of forward reachable set estimation and safety verification of uncertain nonlinear systems with polynomial dynamics are addressed.First,an iterative sums of squares(SOS)programming approach ... In this paper,the problems of forward reachable set estimation and safety verification of uncertain nonlinear systems with polynomial dynamics are addressed.First,an iterative sums of squares(SOS)programming approach is developed for reachable set estimation.It characterizes the over-approximations of the forward reachable sets by sub-level sets of time-varying Lyapunovlike functions that satisfy an invariance condition,and formulates the problem of searching for the Lyapunov-like functions as a bilinear SOS program,which can be solved via an iterative algorithm.To make the over-approximation tight,the proposed approach seeks to minimize the volume of the overapproximation set with a desired shape.Then,the reachable set estimation approach is extended for safety verification,via explicitly encoding the safety constraint such that the Lyapunov-like functions guarantee both reaching and avoidance.The efficiency of the presented method is illustrated by some numerical examples. 展开更多
关键词 Computer mathematics reachable set estimation safety verification sums of squares programming
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Last train timetable optimization for metro network to maximize the passenger accessibility over the end-of-service period
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作者 Fang Wen Yun Bai +2 位作者 Xin Zhang Yao Chen Ninghai Li 《Railway Sciences》 2023年第2期273-288,共16页
Purpose-This study aims to improve the passenger accessibility of passenger demands in the end-ofoperation period.Design/methodology/approach-A mixed integer nonlinear programming model for last train timetable optim... Purpose-This study aims to improve the passenger accessibility of passenger demands in the end-ofoperation period.Design/methodology/approach-A mixed integer nonlinear programming model for last train timetable optimization of the metro was proposed considering the constraints such as the maximum headway,the minimum headway and the latest end-of-operation time.The objective of the model is to maximize the number of reachable passengers in the end-of-operation period.A solution method based on a preset train service is proposed,which significantly reduces the variables of deciding train services in the original model and reformulates it into a mixed integer linear programming model.Findings-The results of the case study of Wuhan Metro show that the solution method can obtain highquality solutions in a shorter time;and the shorter the time interval of passenger flow data,the more obvious the advantage of solution speed;after optimization,the number of passengers reaching the destination among the passengers who need to take the last train during the end-of-operation period can be increased by 10%.Originality/value-Existing research results only consider the passengers who take the last train.Compared with previous research,considering the overall passenger demand during the end-of-operation period can make more passengers arrive at their destination.Appropriately delaying the end-of-operation time can increase the proportion of passengers who can reach the destination in the metro network,but due to the decrease in passenger demand,postponing the end-of-operation time has a bottleneck in increasing the proportion of passengers who can reach the destination. 展开更多
关键词 Urban rail transit Last train of metro Timetable optimization End-of-operation period Passenger demand OD reachability
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An Algorithm to Construct Concurrent Reachability Graph of Petri Nets 被引量:3
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作者 张金泉 倪丽娜 蒋昌俊 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期180-184,共5页
Reachability graph is a very important tool to analyze the dynamic properties of Petri nets, but the concurrent relation of transitions in Petri nets cannot be represented by reachability graph. Petri net is a concurr... Reachability graph is a very important tool to analyze the dynamic properties of Petri nets, but the concurrent relation of transitions in Petri nets cannot be represented by reachability graph. Petri net is a concurrent system, while reachability graph is a serial one. However, concurrency is a kind of property which is not only very significant but also difficult to be analyzed and controlled. This paper presents the concepts of concurrent reachable marking and concurrent reachable graph in order to represent and analyze the concurrent system. The algorithm constructing concurrent reachable marking set and concurrent reachability graph is also shown so that we can study the response problems among services in a network computing environment and analyze the throughput of the system. The Dining Philosophers Problem, which is a classic problem of describing the management of concurrent resources, is given as an example to illustrate the significance of concurrent reachability graph. 展开更多
关键词 Petri nets concurrent system Concurrent reachable Marking concurrent reachable marking set Concurrent Reachability Graph
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Position, Singularity and Workspace Analysis of 3-PSR-O Spatial Parallel Manipulator 被引量:10
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作者 SHAO Jiejie CHEN Wenyu FU Xin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期437-450,共14页
Although the parallel mechanisms have the advantages of high accuracy, velocity, stiffness, and payload capacity, the shortcomings of the space utilization and workspace limit the applications in the confined space. A... Although the parallel mechanisms have the advantages of high accuracy, velocity, stiffness, and payload capacity, the shortcomings of the space utilization and workspace limit the applications in the confined space. A novel 3 degrees of freedom spatial parallel manipulator 3-PSR-O(prismatic-spherical-revolute) is proposed, which possesses a compact architecture and extended workspace while maintaining the inherent advantages of the parallel mechanisms. The direct-inverse position, singularity and workspace are investigated. The mapping method is adopted in the position analysis, and the closed form solution is derived in the form of a six order equation. The singularity analysis of the mechanism is also carried out based on the geometrical constraints, including six singularity boundaries. A feature boundary, which is independent of the prismatic joints' stroke limit, is obtained by integrating the six singularity boundaries. According to the formation of the reachable workspace, a concept of basic workspace is also introduced and presented in the analytical way. By demarcating the basic workspace along the central height with the feature boundary, the reachable workspace can be derived and analyzed more efficiently. Finally, a comparative study on the space utilization between the 3-PSP parallel mechanism and the new mechanism is also presented. The area of feature boundary of the new mechanism is about 140% of the 3-PSP parallel mechanism, while its installation radius is only 1/2 of the 3-PSP parallel mechanism. The proposed parallel mechanism shows great space utilization, and is ideally suited for applications in confined space occasions such as immersion lithography, nano-imprint etc. 展开更多
关键词 spatial-planar parallel mechanism direct-inverse position analysis reachable workspace basic workspace feature boundary
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Bitcoin Network Measurement and a New Approach to Infer the Topology 被引量:2
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作者 Ruiguang Li Jiawei Zhu +3 位作者 Dawei Xu Fudong Wu Jiaqi Gao Liehuang Zhu 《China Communications》 SCIE CSCD 2022年第10期169-179,共11页
Bitcoin has made an increasing impact on the world's economy and financial order,which attracted extensive attention of researchers and regulators from all over the world.Most previous studies had focused more on ... Bitcoin has made an increasing impact on the world's economy and financial order,which attracted extensive attention of researchers and regulators from all over the world.Most previous studies had focused more on the transaction layer,but less on the network layer.In this paper,we developed BNS(Bitcoin Network Sniffer),which could find and connect nodes in the Bitcoin network,and made a measurement in detail.We collected nearly 4.1 million nodes in 1.5 hours and identified 9,515 reachable nodes.We counted the reachable nodes'properties such as:service type,port number,client version and geographic distribution.In addition,we analyzed the stability of the reachable nodes in depth and found nearly 60%kept stable during 15 days.Finally,we proposed a new approach to infer the Bitcoin network topology by analyzing the Neighbor Addresses of Adjacent Nodes and their timestamps,which had an accuracy over 80%. 展开更多
关键词 Bitcoin network reachable nodes node properties node stability network topology
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Optimization control of systemic condition of satellite prototype based on hybrid system
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作者 安实 龙江 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第4期552-557,共6页
This article proposes an optimization control model of the systemic condition of satellite prototype based on the hybrid system. A dynamic programming algorithm is also proposed because the problem is NPhard. An empir... This article proposes an optimization control model of the systemic condition of satellite prototype based on the hybrid system. A dynamic programming algorithm is also proposed because the problem is NPhard. An empirical study validates the model and the algorithm,and proves that the pointed important management resources can be recognized and allocated optimally and correctly. 展开更多
关键词 systemic condition dynamic programming reachable net satellite prototype
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Applying a semantic information Petri Net modeling method to AUV systems design
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作者 冯晓宁 王朔 +1 位作者 王卓 刘群 《Journal of Marine Science and Application》 2008年第4期273-277,共5页
This paper informally introduces colored object-oriented Petri Nets(COOPN) with the application of the AUV system.According to the characteristic of the AUV system's running environment,the object-oriented method ... This paper informally introduces colored object-oriented Petri Nets(COOPN) with the application of the AUV system.According to the characteristic of the AUV system's running environment,the object-oriented method is used in this paper not only to dispart system modules but also construct the refined running model of AUV system,then the colored Petri Net method is used to establish hierarchically detailed model in order to get the performance analyzing information of the system.After analyzing the model implementation,the errors of architecture designing and function realization can be found.If the errors can be modified on time,the experiment time in the pool can be reduced and the cost can be saved. 展开更多
关键词 autonomous underwater vehicle (AUV) colored Petri Net modeling language (CPNML) substitution transition reachable tree
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Economical and Environmental Effects of Pressure Reducer Valve Substituting by Small Hydro Power-Plants in Gravity Water Transmission Pipelines in Iran
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作者 Amir Bashirzadeh Tabrizi Nassir Gifani 《Journal of Energy and Power Engineering》 2012年第2期209-215,共7页
In this work, historical background of power generation by small hydro-power plants across the world and specially across the Iran with emphasis on small hydro-power plant utilization as recovery turbine in water tran... In this work, historical background of power generation by small hydro-power plants across the world and specially across the Iran with emphasis on small hydro-power plant utilization as recovery turbine in water transmission pipeline have been attended firstly, and then, three water transmission pipelines from Chah-nemie to Zahedan city, Shirindare dam to Bojnord city and Mokhtaran desert to Birjand city in Iran have been studied as case study samples. According to the sample pipeline characteristics and pipeline topography, reachable energy have been estimated; in the next step, pay attending to reachable energy, initial investment cost, total benefit of operating period, benefit to cost ratio and other economical parameters for small hydro-power plants in case study pipelines have been presented and generated power cost of the same amount via other resources compared to the hydro-power cost. At the end, in agreement with environmental advantages of small hydro-power plants, the methods of generated power utilization, proper solution for optimization of reachable energy in water transmission pipeline and substitution of pressure reducing valve by small hydro-power plant in the pipelines as a major solution for energy recovering in water pipelines have been proposed. 展开更多
关键词 Water transmission pipeline small hydro power-plant reachable energy renewable energy.
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