Air conditioners is expected to be the second largest source of growth in global electricity demand. To promote electrification, heat pump air conditioner is encouraged to replace natural gas furnace. Improving heat p...
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Air conditioners is expected to be the second largest source of growth in global electricity demand. To promote electrification, heat pump air conditioner is encouraged to replace natural gas furnace. Improving heat pump's energy efficiency can help reduce global energy consumption and greenhouse gas emissions. Annual performance factor is one of the key metrics to evaluate heat pump systems' energy performance. Seeking annual performance factor maximum belongs to an optimization problem with multi constraints. However, due to the nested variables, continuous non-differentiable and piecewise form of annual performance factor definition functions, the optimized objective function is usually based on the simplification with large errors. Meanwhile, the multi constraint boundaries are either ignored or considered but through complicated and high-cost tests. In this research, the variable iteration logic of the annual performance factor definition functions is sorted firstly. Then the above exact mathematical definitions are programmed as the objective functions without any simplification. Enumeration method is used to establish the annual performance factor maximum solution algorithm. More importantly, taking a 3.5 kW cooling capacity mini-split heat pump prototype as an example, energy performance tests are conducted to fit the multi constraints, namely using less global parameters to cover more local parameters, which greatly simplifies the test procedures and cost. Then, using our proposed method, the maximum annual performance factor is predicted and validated by experiments. The prediction accuracy is 99.6%, with a 38.4% improvement compared to the best reported value from literature. Based on the recommended variable values, the prototype's annual performance factor achieves the maximum with a 7.71% improvement from the baseline. The proposed method can save time and experimental resources in the product development stage compared with the traditional trial and e
Despite the as ailability of services with similar functionality but from different providers in the cloud, using them in a workflow might subject to constraints such as service QoS and service bundling. Service ice b...
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ISBN:
(纸本)9781467372817
Despite the as ailability of services with similar functionality but from different providers in the cloud, using them in a workflow might subject to constraints such as service QoS and service bundling. Service ice bundling refers to the situation where here the subscription of two services have to be done together;such requirement might he imposed by service providers and/or by the alliance group that the providers join in. In this paper, we focus on the set's ice selection problem under the QoS constraints from the user and the bundling constraints associated with the chosen services. We first formulate the service selection problem as a multi-constrained selection problem. Then we propose a recursive heuristic search algorithm that takes the required QoS and bundling constraints into consideration for service selection. This algorithm has two unique functions: (i) utility function to measure the quality of the selection strategy under consideration, and (ii) acceptance function to limit the selection strategy only to those potential service candidates that have higher chance to satisfy the bundling constraints. Experiments show that our proposed solution can find better solutions than the existing ones without too much extra performance overhead.
The integrated guidance and control (IGC) is a method to improve the traditional separation guidance and control design for unmanned aerial vehicles (UAV). The advantage is that this design fully considers the couplin...
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The integrated guidance and control (IGC) is a method to improve the traditional separation guidance and control design for unmanned aerial vehicles (UAV). The advantage is that this design fully considers the coupling relationship between guidance and control loops, and the full-state control of the UAV can be taken into account, thereby improving the accuracy of guidance. This paper provides a review and discussion of current work on the design of IGC systems. The difficulty in designing an IGC system is that the order of the IGC system is high, and the coupling between states is strong, making the controller design difficult. Its research focuses on IGC methods that satisfy complex multi-constraint conditions, IGC methods with rapid convergence and strong robust IGC methods under uncertainty and unknown disturbances, etc. This paper also discusses possible future work on IGC methods of UAVs, including fault-tolerant and anti-noise IGC methods under harsh working conditions, cooperative IGC design of UAVs and intelligent IGC methods.
multi-constrained optimal routing problem and disjoint path selection are NP-hard problem. The conventional single-path and single constraint routing can not meet people's needs. The reliability of network data tr...
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ISBN:
(纸本)9781510821873
multi-constrained optimal routing problem and disjoint path selection are NP-hard problem. The conventional single-path and single constraint routing can not meet people's needs. The reliability of network data transmission and packet loss rate can be decreased when the route or the transmission fails. To solve the problems, we need to study the routing path selection strategies. This paper optimizes the routing path that meets the QoS constraints under the SDN pre planning routing, and proposes a routing mechanism that can solve problems in polynomial time. Firstly, the paper combined with Clustering and Gauss algorithm to simulate the network simulation, obtain the initial experimental data. It can reflect the network status more accurately. Secondly, simplify the multi-objectives based on the AHP, It reduces the complexity of the problem and meets QoS requirements. Finally, select the disjoint communication paths and backup paths with the heuristic algorithms in order to balance the load of network and improve the transmission reliability. The selection mechanism can improve the efficiency of data transmission, and the survival of network communication.
In this paper, an optimal disposition method based on chaos genetic algorithm (AGA) is presented for radar netting. A mathematical model for radar optimal disposition is established according to the analysis of region...
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ISBN:
(纸本)9781728101057
In this paper, an optimal disposition method based on chaos genetic algorithm (AGA) is presented for radar netting. A mathematical model for radar optimal disposition is established according to the analysis of regional radar netting at the beginning. And then, the solving process of AGA for this optimization problem is discussed. The adaptive crossover probability and adaptive mutation probability are proposed, which consider the influence of every generation to algorithm and the effect individual fitness in every generation. Finally, through analyzing an example, it comes to a conclusion that several optimal deployment of radar networks can be obtained much more quickly by this method with better operability.
This paper proposes a new filter design optimized for GNSS attitude determination applications using low cost devices. The filter contains all relevant constraints and observations, including double differenced carrie...
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ISBN:
(纸本)9781538604854
This paper proposes a new filter design optimized for GNSS attitude determination applications using low cost devices. The filter contains all relevant constraints and observations, including double differenced carrier phase and code observations along with MEMS-IMU observations. Benefited from the unified treatment, the priori information is well used during the resolution of double differenced GNSS observables. Hence, the success rate of integer ambiguity resolution as well as attitude determination is improved. A set of experiments were conducted to evaluate the performance of the method, compared with the traditional method. This paper uses RTKLIB[1], an open source platform to provide the results of traditional method. The new filter is proved to be capable of improving the attitude determination accuracy and reliability. Apart from the validation, a proposal for future work is also attached in this paper.
The recent advances in wireless technology has enabled users of Mobile cellular networks in different parts of the world not only to communicate with each other but also to participate in real time applications, viz.,...
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The recent advances in wireless technology has enabled users of Mobile cellular networks in different parts of the world not only to communicate with each other but also to participate in real time applications, viz., video conferencing, multiparty games, online auctions, access to distributed databases, etc., on the fly. All these applications require a multicast Tree (MT) to be constructed among the group users with the source being the root of the MT. Traditional methods used in a wired network to construct a MT take into account only the distance or delay between the nodes. These methods when extended to mobile networks fail because of the inherent dynamism in a mobile network. To overcome this problem and to give an optimized solution to this problem, a novel Genetic Algorithm (GA) based approach to construct an Optimal multicast Tree (OMT) with four constraints viz., probability of delay over a path, queuing delay at a node, residual bandwidth of a link, and the speed of the user is proposed in this paper. Further, for a network of N nodes and E edges, with k independent constraints, it has been derived that the time complexity and space complexity for GA based algorithm are O(N-2) and O(N), respectively, whereas the time complexity and space complexity for the non-GA based multi constrained algorithm are O (N-2k) and O(N-2). These results show that the GA based algorithm is insensitive to the number of constraints and it constructs OMT faster than the traditional algorithms. (c) 2006 Elsevier B.V. All rights reserved.
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