65 results about "Branch and bound method" patented technology

The invention discloses a power grid optimal planning method of a large-scale grid-connected wind farm, comprising the following steps of: step 1, obtaining net rack planning data, system operation predication data and wind power planning data; step 2, constructing a calculation model comprising a target function and a constraint condition of the model; step 3, setting calculation parameters; and step 4, inputting the net rack planning data, the system operation predication data and the wind power planning data, which are obtained by the step 1, and three parameters set by the step 3 into the calculation model constructed in the step 2; utilizing optimization algorithms including a Benders decomposition method, a branch and bound method and the like to solve through a computer. According to the method provided by the invention, a 'peak property' of wind power output is considered and the economic rationality of a power grid optimal planning scheme is ensured through allowing a wind power output peak value with a smaller probability; and the method provided by the invention comprehensively considers two aspects on newly-constructed line investment and wind power comprehensive benefits, and simultaneously ensures the line utilization rate and the wind power comprehensive benefits.

The present invention provides a time-space dimension decomposition-based airport gate position allocation method and a system. The method comprises the steps of dividing all flights according to a preset time period and the airport running time of each flight so as to obtain a flight set corresponding to each time period; according to the preset attribute of each gate position, dividing all gate positions to obtain gate position sets corresponding to the attributes of the gate positions; according to flight sets and gate position sets, establishing a constraint condition and an 0-1 integer planning model; based on the branch and bound method, solving out the solution of the 0-1 integer planning model and obtaining a gate position allocation scheme. According to the technical scheme of the invention, the allocation efficiency of airport gate positions is improved and allocation results are optimized. Meanwhile, the efficient and safe operation of an airport is facilitated.

The invention provides a method for generating a long-term maintenance strategy of an electric distribution system in view of ageing properties of an element. The method comprises the following steps of: step 1, collecting information to form a maintenance basic database for electric distribution; step 2, establishing a long-term maintenance optimizing model of the electric distribution system; and step 3, calling the maintenance basic database formed in the step 1, substituting the maintenance basic database into the long-term maintenance optimizing model of the electric distribution system in the step 2, and solving by using a branch-and-bound method to obtain the long-term maintenance strategy of the electric distribution system in view of the ageing properties of the element. From a view point of the electric distribution system, based on a time-variation ageing model of transformer and breaker equipment, the method provided by the invention can be used as a support of an electric distribution automatic system to effectively establish the long-term maintenance strategy of the electric distribution system by taking a minimum sum of a maintenance cost in a maintenance period and a cost caused by faults as a target function, considering losses to users and electric power companies which are caused when the equipment is stopped in the process of maintaining, and comprehensively considering the influence of the maintenance on the improvement of a failure rate of the equipment and the reliability of the system.

Provided are methods for creating a synthetic gene for expression in a host organism, by providing a data set representative of codon pair translational kinetics for the host organism which includes translational kinetics values of the codon pairs utilized by the host organism, providing a desired polypeptide sequence for expression in the host organism, and generating a polynucleotide sequence encoding the polypeptide sequence by analyzing candidate nucleotides to select, where possible, codon pairs that are predicted not to cause a translational pause in the host organism, with reference to the data set, thereby providing a candidate polynucleotide sequence encoding the desired polypeptide. The methods can be performed using multiple parameter nucleotide sequence optimization methods, such as branch-and-bound methods for nucleotide sequence refinement.

The embodiment of the application discloses an AVC (Automatic Voltage Control) system-based reactive voltage optimization method. The method comprises the following steps of: receiving a CIM (Common Information Model) which is derived through an SCADA (Supervisory Control And Data Acquisition) system; receiving input and switching out status information of reactive-load compensation equipment which is derived through a PI (Plant Information System), and reactive-load measurement section real-time data of transformer substations; on the basis of the CIM, optimally calculating the input and switching out status information of the reactive-load compensation equipment and the reactive-load measurement section real-time data through an optimized reactive voltage algorithm, and generating an optimized strategy, wherein the optimized reactive voltage algorithm comprises a primary dual interior point method, a branch-and-bound method and / or a voltage correcting control model method; and the AVC system controls optimization of the voltage according to the optimized strategy. The embodiment of the application further discloses an AVC system-based reactive voltage optimization device. Utilization efficiency of electrical energy can be improved through the embodiment of the application.

The invention provides a method for assisting mobile unloading of users by multiple unmanned aerial vehicles, and belongs to the field of mobile cloud computing. The method comprises the steps of carrying out modeling on mobile migration of uploading and downloading requirements of multiple users from three aspects of unmanned aerial vehicle resource allocation, flight path planning and task allocation; and then converting and relaxing the model by a three-stage iterative algorithm, and performing iterative solution by using a branch-and-bound method to obtain an optical resource allocation, task allocation and flight path planning scheme. The mobile unloading method provided by the invention has the beneficial effects that the uploading demand and the downloading demand of the users are simultaneously taken into consideration, and the calculation rate of the users is greatly improved; and the mobile unloading method provided by the invention realizes the fairness of the users by maximizing the minimum calculation rate in all of the users.

The invention aims at a multi-relay system with an energy harvesting function and provides a method for optimal distribution of time of an energy harvesting relay system based on relay selection. In the method, a plurality of relay nodes work under an energy harvesting mode of wireless energy transmission (WET), an optimization model with maximum system end-to-end throughput is constructed based on the limitations of energy causality and data causality, and a branch and bound method is adopted to select the relay node used by each time slot. A simplex method and an independent solution method are respectively adopted to carry out optimal distribution on the transmission time of the source node and the relay node in each time slot for different service conditions of the relay node about the residual energy, so that the data quantity received by the target node is improved. According to the method, pairing of the relay node and the transmission time slot during multi-relay cooperation and optimal distribution of the transmission time of the source node and the relay node are realized, so that the system throughput performance is effectively improved, and the method has an advantage that the energy consumption expenditure is saved.

The invention discloses a distribution network regional voltage distributed coordinated control method and system. The method comprises a step of determining the installation positions of line voltageregulators in a power transmission line when there is no light, a load is maximum and a voltage loss rate is smaller than a set value, a step of dividing the power transmission line into multiple regions by using the installation positions of the line voltage regulators as boundaries, a step of establish a regional optimization model with the minimalization of the active loss of the power transmission line and the total cost of loss of photovoltaic power generation in the regions as an optimization target, a step of performing distributed coordination optimization between the regions by usingan alternating direction multiplier method and determining the optimal objective function of each regional optimization model and the boundary voltage of each region after distributed coordination optimization, and a step of determining the gear positions of the line voltage regulators by using a branch bound method, and regulating the voltage of each region of a distribution network. According to the invention, the problems of the time and space mismatch of a power supply with a high-permeability photovoltaic distribution network and the load and voltage out-of-limit can be solved.

The invention discloses a track space-time conflict based integer programming modeling method, which comprises the steps of station route information collection, train selectable route matching, integer programming modeling and model solving and operation process output, wherein in the step of station route information collection, information of tracks required to be passed in order to use each in-route at a conflict-free state, turnout information and occupation time information of each track are collected; in the step of train selectable route matching, a train route matching operation is performed on each train with an operation plan to be compiled, and an in-route pair set is generated; in the step of integer programming modeling, variable and symbol definition, constraint definition and target definition are performed, and a plurality of object lists are generated; and in the step of model solving and operation process output, a model is solved by using a branch and bound method, and the train is compiled. The method disclosed by the invention is high in equipment utilization rate and high in compiling efficiency, and can set different compiling objectives, optimize the compiling structure and avoid conflicts of trains; and the safety on the aspects of time and space is guaranteed.

The invention discloses a day-ahead reactive power optimization method based on a branch-bound method and a primal-dual interior point method and belongs to the reactive power optimization technology field of a power system. The method is characterized in that constraints of discrete variables in each period, adjusting gears in adjacent period and whole-day operation times are considered, and primary problems are branched and combined with branched branch-cutting strategies according to the periods, so that all discrete variables gradually approach to discrete values and meet the coupling constraints among the period; the primary problems are decomposed into a series of single-period reactive power optimization sub-problems only containing continuous variables after being branched according to the periods, the sub-problems are solved by adopting the primal-dual interior point method, and the calculated amount is reduced. The day-ahead reactive power optimization method is excellent in convergence, high in reliability and steady in calculation result.

The invention discloses a wind power storage energy power and capacity optimization and configuration method based on economic dispatching. A weibull probability curve of wind power is established; a random planning model of a wind power system energy storage apparatus is established based on economic dispatching; and the random planning model of the energy storage apparatus, established by a "2m+1" point estimation method, is solved by adopting a parallel branch and bound method to obtain an optimal power and capacity configuration scheme of the energy storage apparatus. Aiming to solve the problem in wind storage effective matching in uncertain wind power environment, the random planning model of the energy storage apparatus with optimal power and capacity configuration is proposed; and based on a comprehensive solving scheme with point estimation and parallel branch and bound strategies, the energy storage random planning model is rapidly and effectively solved, so as to determine the optimal power and capacity configuration scheme of the energy storage apparatus.

The invention discloses a method for inquiring visible neighbours of moving objects in the environment with barriers. The neighbour inquiry technology of the moving objects in a spatial database is utilized and the existing branch and bound algorithm is utilized to inquire the neighbours which are not blocked in the environment with barriers. In the spatial data, R-tree index is utilized for the barriers, TPR-tree index is utilized for the moving objects, the branch and bound algorithm is utilized to traverse the indexes, and meanwhile inquiry is realized by combining calculation of the blocking time of the moving objects. The method has the following beneficial effects: utilizing the existing indexing technology and the moving object neighbour inquiry technology in the spatial database and researches and achievements in the environment with barriers, providing the method of inquiring the moving objects which are not blocked in certain period in the environment with barriers, ensuring that the users can select the optimum inquiry time interval according to the application requirements and providing best performances.

The invention discloses an area spectral efficiency (GASE) based TDMA wireless Mesh network resource allocation method. The problem of low network energy efficiency caused by sharp increase of wireless network energy consumption is mainly solved. According to the technical scheme, the area spectral efficiency is used as an optimization goal to establish an optimization model; the model is decomposed into a power allocation model and a time slot allocation model; a nonlinear simplex method and an interior point penalty function method are adopted to solve the power allocation model, a branch and bound method is adopted to solve the time slot allocation model on the basis of power allocation to complete time slot allocation, namely resource allocation. The GASE based TDMA wireless Mesh network resource allocation method gives consideration to the power allocation while achieving resource allocation of a TDMA wireless Mesh network, accordingly improves the energy utilization efficiency of the network, reduces the energy consumption of the network and can be used for the TDMA wireless Mesh network.

The invention relates to an industrial wireless network deterministic scheduling method supporting transmission delay optimization, and belongs to the technical field of industrial wireless networks.For a small-scale network, a branch and bound method based on link conflict classification is adopted; the method is an optimal algorithm; due to release-state link classification, pruning condition judgment on an effective link subset is carried out; continuous searching is carried out in a solution space tree; when the network has a feasible solution, a scheduling solution satisfying deterministic demands can be searched through the algorithm; for a large-scale network, a heuristic scheduling algorithm based on maximum parallel transmission is adopted; and, due to combined scheduling on thelink conflict degree and the loose degree, the scheduling solution can be obtained in a relatively short time. According to the scheduling method provided in the invention, on the premise that the deterministic transmission demands of a data flow are satisfied, the network average transmission delay also can be reduced; and the overall communication performance of the network is improved.

The invention discloses a method for automatically sorting demand response users. Some users are selected from remaining response users as candidate sorting users of the round, and an integer linear planning model is established according to power load gap and load reduction capability of the candidate users. The solution is obtained through the branch and bound method to interact with users. Whether a next round of sorting is necessarily is determined according to feedback, and process is repeated until the power load gap defined by an upper-level system is met. The method adheres to the sorting principles of fairness, higher priority with higher creditability and maximally approaching the power load gap, and flexible interaction with power users and multiple rounds of dynamic sorting ensure matching level with the power load gap. Users are fairly selected to participate in demand response, the power user participation is improved, and the risk that real response capacity can not satisfy the expected power load gap capacity is reduced.

The invention provides a thermal storage tank capacity optimization configuration method used for increasing a wind power absorption ability and a system thereof. The method comprises the following steps of establishing a thermal storage tank capacity optimization configuration model which includes a thermal storage tank capacity optimization configuration target function and a corresponding constraint condition; and using a branch and bound method to solve the thermal storage tank capacity optimization configuration model and completing thermal storage tank capacity optimization configuration. By using the thermal storage tank capacity optimization configuration method used for increasing the wind power absorption ability and the system thereof, randomness and fluctuation performance of wind power output, a thermal load demand of a user and thermal storage and release characteristics of a thermal storage tank are integratedly considered so as to realize flexible output adjusting of a heat supply unit and increase a wind power utilization rate.

The invention provides an optimization method and device for integrated compilation of a crew routing plan and a duty plan. The method comprises the following steps: receiving a given period of a motor train unit crew routing plan, a routing table of a motor train unit and the number of crew affair groups of the motor train unit, which are input by an external terminal; establishing a space-time continuous network according to the given period of the motor train unit crew plan and the intersection table of the motor train unit; a set coverage model based on the space-time continuous network and taking monthly man-hour balance of each crew group of the motor train unit as an objective function; and solving the set coverage model by adopting a column generation algorithm and a branch and bound method to obtain a crew plan of each crew group of the motor train unit, and sending the crew plan of each crew group to the external terminal. The high-speed railway crew compilation system can automatically compile the high-speed railway crew, so that the automation degree of the high-speed railway crew and the transportation efficiency of the high-speed railway are improved.

The invention discloses a multifunctional networked radar task planning method based on a branch-and-bound method. The multifunctional networked radar task planning method adopts the branch-and-boundmethod of a tree structure to realize the traversing of a feasible solution of a problem, and introduces a pruning operation so as to reduce the computation amount significantly. The multifunctional networked radar task planning method can plan radar tasks with different parameters and priorities into radar units of a radar network, and ensures load balance of the radar units. Although an existingheuristic radar task planning method can complete the radar task planning, the existing heuristic radar task planning method can only acquire a suboptimal solution, and the computation cost is hard to estimate. Compared with the existing heuristic method, the total cost of a radar task planning scheme obtained by adopting the multifunctional networked radar task planning method is lower.

The invention discloses a resource allocation method based on equivalent capacity in a wireless virtual network, for solving the problem of resource virtualization and distribution and service flow admission control. The method comprises the following steps: importing an SC-FDMA uplink system to serve as a wireless virtual network system; establishing a finite state Markoff channel model, and obtaining carrier resource statistical information; obtaining equivalent bandwidth information according to different service requests; giving a QOS index sequence to obtain equivalent capacity information; establishing an optimal resource allocation model according to the equivalent bandwidth information and the equivalent capacity information; and resolving the optimal resource allocation model by using a branch and bound method to obtain an optimal equivalent capacity resource allocation scheme. According to the resource allocation method disclosed by the invention, the resource measurement is more accurate and compact, the resource utilization rate is improved, a dynamic pricing mechanism is imported, so that the resource allocation between virtual networks is more balanced and rational, the access rate is high, the delay is shorter, a flexible and varied resource allocation scheme and admission control technology are provided, and a new technical scheme is provided for the implementation of virtual operators.

The invention discloses a multi-mode public transport time table optimizing method for last transfer demand. The method comprises the following steps: screening a key transfer relation and an associated site according to passenger flow characteristics; acquiring running information of rail transit and ground public transportation based on a planned time table and historical running data; acquiring a passenger transfer walking time and a number of bus station parking berths through investigation; proposing a time table optimization target and an adjusting strategy, and establishing a night-time time table two-stage optimization model; establishing a time table optimization model for a last train transfer problem of the rail transit at a first stage, and acquiring an optimum adjusting scheme by utilizing a branch and bound method; and at a second stage, based on the rail transit time table generated at the first stage, considering the constraint of the bus station berths number, establishing a bus time table optimization model for the ground public transportation and the rail transit last train transfer problem, and acquiring an optimum adjusting scheme by utilizing a branch and bound method. The method can be used for systematically decreasing a transfer failure rate in a multi-mode public transport network.

The invention discloses a WAMS-based low-frequency oscillation decentralized controller design method considering interaction which can be applied to low-frequency oscillation control of a power system. The method comprises the steps of: acquiring modal information by integrating multiple identification results; identifying controllability and observability by adopting a state subspace model identification method (N4SID), and determining installation positions of controllers and candidate feedback signals; transferring functional matrix definition according to MIMO for identification and solution row by row, calculating a highly-controllable low-interaction control loop combination by utilizing a branch and bound method, and converting a complex multi-controller coordination design problem into a simple decentralized controller independent design problem; designing a PSS for a region pattern by adopting an identification-based pole placement method, and designing the controllers for an interval pattern by adopting a model prediction control method. The good control effects of the two types of independently designed controllers verify effectiveness of the WAMS-based low-frequency oscillation decentralized controller design method. The WAMS-based low-frequency oscillation decentralized controller design method provides a new idea for designing a multi-damping controller based on identification coordination.

The invention relates to a comprehensive coordination control policy of the reactive voltage of a power distribution network, and belongs to the technical field of voltage control of the power distribution network. The coordination control policy is executed by following steps: 1) acquiring parameters of the power distribution network; 2) establishing an equivalent network of the power distribution network; 3) calculating a power grid voltage deviation value of the power distribution network based on the equivalent network in step 2; 4) setting a target function and constraint conditions; 5) solving the target function and the constraint conditions; 6) determining integral solutions of solutions or a solution set in step 5) by employing a branch and bound method; and 7) forming a final combined coordination control scheme according to the integral solutions obtained in step 6), and giving a control command of the transformer gear position and capacitor set switching. According to the method, optimization is realized in consideration of characteristics and communication conditions of regional power distribution network equipment by regarding the minimum global node voltage deviationdegree as the target, and effects of improving the power factor of the power grid and reducing the transmission loss are achieved.

The invention provides an optimized operation method of a cool and thermal power comprehensive energy system. The optimized operation method comprises the steps of: 1) taking the optimal overall operating economic efficiency of the cool and thermal power comprehensive energy system as the core, considering multi-time scale characteristics of the cool and thermal power comprehensive energy system,and constructing a system operating total cost minimum objective function; 2) establishing an equipment constraint model and a power balance constraint model as the multi-time scale characteristics ofthe cool and thermal power comprehensive energy system are considered, and regarding the equipment constraint model and the power balance constraint model as constraint conditions of the system operating total cost minimum objective function; 3) and adopting a branch and bound method, and solving the system operating total cost minimum objective function according to the constraint conditions instep 2). For the complex structure and operation mechanism of the cool and thermal power comprehensive energy system, the optimized operation method can improve the energy utilization rate, reduces the operating cost, and realizes the optimized operation of the cool and thermal power comprehensive energy system.

The invention discloses a matching game-based separation multi-access method in an ultra dense heterogeneous network. The method is based on a user separation multi-access mechanism, that is, user equipment is allowed to access multiple base stations in uplink and downlink so as to enjoy services and transmit data. The invention provides a low-complexity matching game method based on a matching game theory. One or more base stations are selected for a user to connect according to quality of service requirements of the user, user utility in the network is maximized, further, actual needs of different users are met. The problem of user separation multi-access in the ultra dense network is solved through the matching game method, so that the user utility in the network is maximized and the quality of service requirements of different users are met. Compared with traditional exhaustive search and branch and bound methods, the method has the advantage of low complexity. The method represents a new possibility solving the problem of user multi-access in the ultra dense network.

The invention discloses a voltage source converter-comprising alternating current and direct current series-parallel power grid reactive optimization method, and belongs to the field of optimization and dispatching of an electric power system. At current, reactive regulation after flexible direct current power transmission is introduced is not taken into consideration in an AVC strategy, and an effective active and reactive closed loop control method for the voltage source converter is absent. The reactive optimization method comprises the steps of establishing a flexible direct current powertransmission system reaction model; establishing a reactive optimization constraint condition of the flexible direct current power transmission system, and a target function, obtaining a reactive optimization model, and solving the reactive optimization model according to the set constraint condition; and specific to the established reactive optimization model, solving the target function by adopting a branch and bound method in combination of a prime-dual interior point method. By virtue of the technical scheme, the flexible direct current convertor station reactive model is established, andthe targeted reactive control method is designed, so that the reactive adjustment capability of the voltage source converter is utilized fully, the voltage control capability in the alternating current and direct current power grid series-parallel condition is improved, and network loss is lowered.

The invention discloses a power system production simulation method with an electricity quantity adjusting layer. The method divides a production simulation process into two layers and multiple subcycles. In the first layer, firstly distribution and dispatch of adjustable power source energy are processed during the subcycles. In the second layer, unit commitment problems are solved by the adoption of a branch and bound method during the subcycles according to the result after regulation, and after all the problems are solved in all the subcycles in sequence, a production simulation result iscounted and obtained. According to the technical scheme, the power system production simulation method with the electricity quantity adjusting layer improves production simulation calculation efficiency and ore adequately embodies the adjusting property of an adjustable power source meanwhile, the accuracy of the production simulation result is improved, and the needs for project practicability are satisfied.

The invention provides a three-phase reactive power optimization method of an active power distribution network. The three-phase reactive power optimization method comprises the steps of inputting trend data, and constructing a three-phase active power distribution network reactive power optimization model in consideration of an interphase mutual inductance of the branch circuit in a manner that the least value of a power distribution network active network loss is used as an objective function; converting the three-phase active power distribution network reactive power optimization model to a semi-definite programming relaxation model, and solving according to a semi-definite programming method; processing a discrete variable according to a sensitivity analysis method and a branch-and-bound method, and obtaining an iterative value; substituting the iterative value into the semi-definite programming relaxation model, and solving again until an optimization model optimal solution which contains the discrete variable. The three-phase reactive power optimization method of the active power distribution network realizes reactive power optimization calculation of a three-phase active power distribution network and furthermore realizes accurate expression for different-type load conditions in the power distribution network.

The invention discloses an unmanned aerial vehicle flight path distribution method and device. Through an improved path distribution algorithm based on a basic idea of a branch and bound method, the min-max integer planning problem of path distribution is solved; and then through an optimized solution, optimal flight paths corresponding to all unmanned aerial vehicles are obtained and distributedto finish a flight task. The unmanned aerial vehicle flight path distribution method and device can help a user to solve the problems in ensuring the parallel flight time of the multiple unmanned aerial vehicles to be shortest and realizing the optimal path distribution on the premise that the unmanned aerial vehicles finish the flight task and meet the constraint conditions.

The invention belongs to the field of mobile cloud computing, and particularly relates to a multi-user computing migration method based on multi-radio frequency communication. The method comprises thefollowing steps: a controller models the multi-radio frequency multi-user computing migration problem by using a multi-radio frequency multi-user computing migration modeling method based on parameter analysis according to the collected information of all users and the target of the system, and obtains an initial problem model Theta; According to the characteristics of the initial problem model Theta obtained in the previous step, the controller relaxes and transforms the model by using the relaxation and linearization method based on McCormick envelope, and obtains the relaxed problem modelTheta *. The controller uses branch-and-bound method to solve the relaxed problem model Theta obtained in the previous step, which maximizes the total number of beneficiaries and reduces the cost of user migration. The method of the invention simultaneously considers the calculation time delay and the calculation energy problem of the user, can meet the diversity of the user requirements, has highdata transmission rate of the user, and greatly improves the utilization efficiency of the multi-radio frequency.

The invention discloses a method for selecting hyperspectral image bands based on extraction of all kinds of important bands. The hyperspectral data of each training sample of the bands are used as a time sequence; smooth denoising processing is carried out on each time sequence through wavelet transformation; the important band sets of the training samples are ensured by extracting the important points of the smoothed time sequences, wherein the important points correspond to the important bands respectively; the important band sets of the training samples are collected to form an initial band set; the final band combination is selected on the basis of the initial band set through a branch and bound method. According to the method, conditional mutual information grouping is introduced in the branch and bound method as constraint conditions, and compared with the search efficiency of the existing fast branch-and-bound search algorithm, search efficiency is improved by about one half.