A hybrid search algorithm consisting of three stages is presented to solve the midterm schedule for thermal power plants (MTSFTPP) problem, where the primary objective is to achieve equal accumulated operating hours o...
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A hybrid search algorithm consisting of three stages is presented to solve the midterm schedule for thermal power plants (MTSFTPP) problem, where the primary objective is to achieve equal accumulated operating hours of installed capacity (EAOHIC) for all thermal power plants during the selected period. First, feasible spaces are produced and narrowed based on constraints on the number of units and power load factors. Second, an initial feasible solution is obtained by a heuristic method that considers operating times and boundary conditions. Finally, the progressive optimality algorithm (POA), which we refer to as the vertical search algorithm (VSA), is used to solve the MTSFTPP problem. A method for avoiding convergence to a local minimum, called the lateral search algorithm (LSA), is presented. The LSA provides an updated solution that is used as a new feasible starting point for the next search in the VSA. The combination of the LSA and the VSA is referred to as the hybrid search algorithm(HSA), which is simple and converges quickly to the global minimum. The results of two case studies show that the algorithm is very effective in solving the MTSFTPP problem accurately and in real time.
This work is part of a research project that analyzes and develops efficient technologies for street lighting systems, and it describes a wireless sensor network system used for controlling and monitoring electrical v...
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This work is part of a research project that analyzes and develops efficient technologies for street lighting systems, and it describes a wireless sensor network system used for controlling and monitoring electrical variables. The street lighting system is composed by an urban network, where delivery rate (with priority related to other aspects), latency, energy efficiency, and fault tolerance are the non-functional requirements. Based on these requirements, this work presents a new network routing mechanism with acknowledgment, named GGPSR. The main purpose is to provide new means to reach high delivery rates in urban networks, with tolerated end-to-end delay values for this type of network. The mechanism consists of selecting nodes from neighbors others than the previously selected in order to find a path towards the destination. Simulation results demonstrate the algorithm fulfills the mentioned requirements. (C) 2011 Elsevier Ltd. All rights reserved.
Network-on-Chip (NoC) replaces the traditional bus-based architecture to become the mainstream design methodology for future complex System-on-Chip (SoC). It introduces the principles of packet switching and interconn...
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Network-on-Chip (NoC) replaces the traditional bus-based architecture to become the mainstream design methodology for future complex System-on-Chip (SoC). It introduces the principles of packet switching and interconnection network into SoC design, and achieves much better performance for its high bandwidth, scalability, reliability, etc. However, thermal problem, such as regional temperature differential and hotspot, is still one of the main designing constraints. This paper proposes a dynamic thermal-balance routing (DTBR) algorithm for Network-on-Chip, which can solve both of the two thermal problems. DTBR is a minimal adaptive routing algorithm based on an architectural thermal model. An efficient thermal-aware router is designed to implement the DTBR algorithm. According to the simulation results, the proposed DTBR algorithm can make the network thermal distribution more uniform and hotspot temperature is cut down about 20% in different traffic patterns. Moreover, DTBR will bring a profit for the performance of packet delay and network throughput compared with other routing algorithms. (C) 2011 Elsevier Ltd. All rights reserved.
A control algorithm has been developed and experimentally validated for guiding swarms of robotic vehicles to acoustic targets. This novel algorithm uses pressure measurements from a set of sensors, each attached to a...
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A control algorithm has been developed and experimentally validated for guiding swarms of robotic vehicles to acoustic targets. This novel algorithm uses pressure measurements from a set of sensors, each attached to a vehicle of the swarm, to deduce energy flows from the environment, and to move in the direction of maximum reflected intensity while controlling constraints between vehicles. The algorithm was validated using a collective of eight hand-placed microphones in an open-space area with a 50-m separation between an emitter and scatterer.
The Fleet Assignment Problem (FAP) of aircraft scheduling in airlines is studied, and the optimization model of FAP is proposed. The objective function of this model is revenue maximization, and it considers comprehen...
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The Fleet Assignment Problem (FAP) of aircraft scheduling in airlines is studied, and the optimization model of FAP is proposed. The objective function of this model is revenue maximization, and it considers comprehensively the difference of scheduled flights and aircraft models in flight areas and mean passenger flows. In order to solve the model, a self-adapting genetic algorithm is supposed to solve the model, which uses natural number coding, adjusts dynamically crossover and mutation operator probability, and adopts intelligent heuristic adjusting to quicken optimization pace. The simulation with production data of an airline shows that the model and algorithms suggested in this paper are feasible and have a good application value.
In pattern matching with the pair correlation distance problem, the goal is to find all occurrences of a pattern P of length m, in a text T of length n, where the distance between them is less than a threshold k. For ...
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In pattern matching with the pair correlation distance problem, the goal is to find all occurrences of a pattern P of length m, in a text T of length n, where the distance between them is less than a threshold k. For each text location i, the distance is defined as the number of different kinds of mismatched pairs (alpha, beta), between P and T[i...i + m]. We present an algorithm with running time of O (min {vertical bar Sigma(P)vertical bar(2) n log m, n (m log m)2/3}) for this problem. Another interesting problem is the one-side pair correlation distance where it is desired to find all occurrences of P where the number of mismatched characters in P is less than k. For this problem, we present an algorithm with running time of O (min{vertical bar Sigma(p)vertical bar n log m, n root m log m}). (C) 2008 Elsevier B.V. All rights reserved.
A digital error correction technique with negligible hardware overhead is proposed for binary successive approximation ADCs. A redundant decision phase is inserted between the normal SAR operations, and the coarse dec...
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A digital error correction technique with negligible hardware overhead is proposed for binary successive approximation ADCs. A redundant decision phase is inserted between the normal SAR operations, and the coarse decision error caused by incomplete DAC settling is corrected by a digital code addition. The relaxed DAC settling requirement for coarse decision increases the conversion speed.
Link adaptation is a radio resource management technique that selects a transport mode based on the experienced channel conditions. The optimum mode is commonly determined so as to maximise the throughput. Although, t...
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Link adaptation is a radio resource management technique that selects a transport mode based on the experienced channel conditions. The optimum mode is commonly determined so as to maximise the throughput. Although, this approach is suitable for best-effort services. it is not tailored for real-time services. Presented is anew link adaptation algorithm designed to improve the transmission of delay-sensitive services. The results demonstrate that significant improvements in terms of transmission delay, throughput and operation of link adaptation itself, can be obtained with the proposed scheme.
Previous work has been put into the creation of a global soil taxonomy using a harmonised dataset of 23 soil properties at 18 depth intervals. The taxonomy consisted of selected soil taxa from the US Soil Taxonomy, Wo...
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Previous work has been put into the creation of a global soil taxonomy using a harmonised dataset of 23 soil properties at 18 depth intervals. The taxonomy consisted of selected soil taxa from the US Soil Taxonomy, World Reference Base for Soil Resources, the Australian Soil Classification, and the New Zealand Soil Classification. In this paper, a nomenclature algorithm was proposed for this established comprehensive taxonomy. Firstly, a Ward dendrogram was calculated from a weighted distance matrix determined from principal components of the taxa. This dendrogram was then cut at three levels, creating 15 groups, 86 subgroups, and 493 sub-subgroups at tiers 1, 2 and 3, respectively. A sequence of consonants was used to name the taxa at each tier alphabetically with "A" and "E" inserted between the consonants of tiers 2 and 3 and "OZEM" appended after the consonants of tier 1. In addition, a distance-based algorithm was used to allocate and name 10 unknown soil profiles to the comprehensive soil taxonomy. It was concluded that the nomenclature algorithm can be easily disaggregated by computer and can be used to understand the inter-relationships between soil profiles from different classification systems. In the future, there is a need to include other soil classification systems to the comprehensive system and assign different weights to the soil properties and depths used to construct the comprehensive soil classification system.
Describes a path generation algorithm for sculptured surface manufacture. Representation and manufacture of three-dimensional sculpture surfaces in computer-aided design/computer-aided manufacturing; Approximation of ...
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Describes a path generation algorithm for sculptured surface manufacture. Representation and manufacture of three-dimensional sculpture surfaces in computer-aided design/computer-aided manufacturing; Approximation of the surface representation by a sequence of straight line segments for graphical displays and linear cutter paths for surface manufacturing on computer-integrated numerical control machines.
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