- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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An image segmentation method using logarithmic kbest gravitational search algorithm based superpixel clustering
摘要： Image segmentation partitions an image into coherent and non-overlapping regions. Due to variations of visual patterns in images, it is a challenging problem. This paper introduces a new superpixel-based clustering method to efficiently perform the image segmentation. In the proposed method, initially superpixels from an image are obtained. The superpixels are further clustered into the required number of regions by a newly proposed variant of gravitational search algorithm namely; logarithmic kbest gravitational search algorithm. Experiments are conducted on the Berkeley Segmentation Dataset and Benchmark (BSDS500). It is affirmed from both visual and numerical analyses that the proposed method is efficacious and accurate in segmenting an image than the other considered segmentation methods.
关键词： BSDS500,Gravitational search algorithm,Kmeans,Superpixel clustering
更新于2025-09-10 09:29:36
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[Lecture Notes in Networks and Systems] Renewable Energy for Smart and Sustainable Cities Volume 62 (Artificial Intelligence in Renewable Energetic Systems) || Validation of Three Level Solar Inverter Based on Tabu Search Algorithm
摘要： Providing electrical energy for oil and gas extraction sites can be a real challenge especially for a large oil and gas company like Sonatrach. Solar energy can be great solution for this issue. This study presents an ef?cient way to convert electrical energy from DC to AC using a modulation strategy called selective harmonic elimination (SHE); this method will be used to optimize the performance of a three level solar inverter for standalone power system. Harmonic pollution is a very common problem in the ?eld of power electronics, this problem can cause multiple problems for power converters and electrical devices and also reduce their lifespan. The SHE modulation strategy allows the elimination of low order harmonics and also control the amplitude of the fundamental component of the output voltage spectrum. In this paper Tabu Search Algorithm (TSA) is used to determine optimum switching angles for a three level solar inverter. Simulation and experimental results are presented in this work.
关键词： Optimization,Tabu Search Algorithm,Solar inverter,Harmonic elimination
更新于2025-09-10 09:29:36
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Molecular Mechanics Simulations and Improved Tight-Binding Hamiltonians for Artificial Light Harvesting Systems: Predicting Geometric Distributions, Disorder, and Spectroscopy of Chromophores in a Protein Environment
摘要： We present molecular mechanics and spectroscopic calculations on prototype artificial light harvesting systems consisting of chromophores attached to a tobacco mosaic virus (TMV) protein scaffold. These systems have been synthesized and characterized spectroscopically, but information about the microscopic configurations and geometry of these TMV-templated chromophore assemblies is largely unknown. We use a Monte Carlo conformational search algorithm to determine the preferred positions and orientations of two chromophores, Coumarin 343 together with its linker, and Oregon Green 488, when these are attached at two different sites (104 and 123) on the TMV protein. The resulting geometric information shows that the extent of disorder and aggregation properties, and therefore the optical properties of the TMV-templated chromophore assembly, are highly dependent on the choice of chromophores and protein site to which they are bound. We used the results of the conformational search as geometric parameters together with an improved tight-binding Hamiltonian to simulate the linear absorption spectra and compare with experimental spectral measurements. The ideal dipole approximation to the Hamiltonian is not valid since the distance between chromophores can be very small. We found that using the geometries from the conformational search is necessary to reproduce the features of the experimental spectral peaks.
关键词： tobacco mosaic virus (TMV),linear absorption spectra,spectroscopic calculations,artificial light harvesting systems,Monte Carlo conformational search,tight-binding Hamiltonian,molecular mechanics,chromophores
更新于2025-09-10 09:29:36
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Robust partitioning and indexing for iris biometric database based on local features
摘要： Explosive growth in the volume of stored biometric data has resulted in classification and indexing becoming important operations in image database systems. Consequently, researchers are focused on finding suitable features of images that can be used as indexes. Stored templates have to be classified and indexed based on these extracted features in a manner that enables access to and retrieval of those data by efficient search processes. This paper proposes a method that extracts the most relevant features of iris images to facilitate minimisation of the indexing time and the search area of the biometric database. The proposed method combines three transformation methods DCT, DWT and SVD to analyse iris images and extract their local features. Further, the scalable K-means++ algorithm is used for partitioning and classification processes, and an efficient parallel technique that divides the features groups causing the formation of two b-trees based on index keys is applied for search and retrieval. Moreover, search within a group is achieved using a proposed half search algorithm. Experimental results on three different publicly iris databases indicate that the proposed method results in a significant performance improvement in terms of bin miss rate and penetration rate compared with conventional methods.
关键词： b-trees,DWT,half search algorithm,DCT,SVD,local features,iris biometric database,scalable K-means++
更新于2025-09-10 09:29:36
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[IEEE 2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA) - Turin (2018.9.4-2018.9.7)] 2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA) - Large-Scale Scheduling with Routing, Batching and Release Dates for Wafer Fabs using Tabu Search
摘要： Semiconductor fabricating facilities (wafer fabs) aim for manageable, heuristics that can reproducibly solve their typical large-scale dynamic complex job shop scheduling problems. Hence, the main contribution of this work is a deterministic tabu search algorithm that sequences, routes and batches the process operations of a continuous reentrant material flow using a large-scale mix of single, flexible (parallel) and batch machines. Due to continuous production, release dates and due dates are considered to minimize job tardiness. Using known large-scale benchmark instances, sixteen neighborhood structures are validated to find a practical compromise between solution quality and computational effort. The result is a novel combination of neighborhoods for simultaneous sequencing, routing and batching that finds good schedules for problem instances of industrial size and complexity in an acceptable time.
关键词： local search,variable neighborhood,due dates,routing,tardiness,large scale,batch,release dates,tabu search,optimization,complex job shop scheduling,flexible machines
更新于2025-09-09 09:28:46
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Hybrid differential evolution algorithms for the optimal camera placement problem
摘要： Purpose – This paper aims to investigate to what extent hybrid differential evolution (DE) algorithms can be successful in solving the optimal camera placement problem. Design/methodology/approach – This problem is stated as a unicost set covering problem (USCP) and 18 problem instances are de?ned according to practical operational needs. Three methods are selected from the literature to solve these instances: a CPLEX solver, greedy algorithm and row weighting local search (RWLS). Then, it is proposed to hybridize these algorithms with two hybrid DE approaches designed for combinatorial optimization problems. The ?rst one is a set-based approach (DEset) from the literature. The second one is a new similarity-based approach (DEsim) that takes advantage of the geometric characteristics of a camera to ?nd better solutions. Findings – The experimental study highlights that RWLS and DEsim-CPLEX are the best proposed algorithms. Both easily outperform CPLEX, and it turns out that RWLS performs better on one class of problem instances, whereas DEsim-CPLEX performs better on another class, depending on the minimal resolution needed in practice. Originality/value – Up to now, the ef?ciency of RWLS and the DEset approach has been investigated only for a few problems. Thus, the ?rst contribution is to apply these methods for the ?rst time in the context of camera placement. Moreover, new hybrid DE algorithms are proposed to solve the optimal camera placement problem when stated as a USCP. The second main contribution is the design of the DEsim approach that uses the distance between camera locations to fully bene?t from the DE mutation scheme.
关键词： Unicost set covering problem,Differential evolution,Hybridization,Optimal camera placement,Row weighting local search,Combinatorial optimization
更新于2025-09-09 09:28:46
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Metrological Analysis of an Optoelectronic Monitoring System for Profilograms of Shells of Rotation
摘要： Metrological analysis of optoelectronic monitoring systems for pro? lograms of shells of rotation was conducted. The optoelectronic systems that execute various methods for searching for the center of a part are examined. A mathematical model of a shell of rotation speci? ed by the pro? logram is considered. The dependence of absolute methodological error on this coef? cient is derived from the modeling results, and conclusions are drawn regarding the feasibility of applying one or another system, depending on the required accuracy and speed.
关键词： spectral analysis,pro? logram,monitoring system,geometric parameters,shell of rotation,method of center of gravity search
更新于2025-09-09 09:28:46
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[IEEE 2018 15th European Radar Conference (EuRAD) - Madrid, Spain (2018.9.26-2018.9.28)] 2018 15th European Radar Conference (EuRAD) - Detection of People Trapped under the Ruins Using Dual-frequency IR-UWB Radar
摘要： Detection of people hidden by obstacles using impulse radio ultra wideband radar has become a keen research nowadays. According to theories of the UWB radar, the lower center frequency is, the better penetrability radar has. And the larger bandwidth is, the higher radar range resolution becomes. In order to detect survivors trapped under the ruins of collapsed buildings, researches commonly focus on the radar with center frequency below 500 MHz. However, the radar with low center frequency always has small bandwidth, so it is relatively insensitive to the weak signal of the survivor. And this may lead to miss detection in search and rescue missions. Therefore, a novel dual-frequency IR-UWB radar system is developed in this paper. It can works alternately at each waveform with two center frequencies, which are 270 MHz and 400MHz. And the equivalent bandwidth of the system is relatively extended to enhance the sensitivity to weak vital signals. Moreover, cross-correlation technique is applied to the processed data of the two channels to improve the detected signal to noise ratio (SNR). The experimental results show that this system can both meet the need of low center frequency and large bandwidth in life detection and the detected SNR of the system is much higher than that of the single-frequency IR-UWB radar. So this system can work more reliably and effectively in the detection of people trapped under the ruins.
关键词： search and rescue (SAR),impulse radio ultra wideband (IR-UWB),cross-correlation,dual-frequency,life detection
更新于2025-09-09 09:28:46
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Weak Echo Detection from Single Photon Lidar Data Using a Rigorous Adaptive Ellipsoid Searching Algorithm
摘要： Single photon lidar (SPL) systems have great potential to be an effective tool for mapping due to their high data collection efficiency. However, the large number of false returns in SPL point clouds represents a huge challenge for the extraction of weak signal targets with low reflectivity or small cross sections. Numerous filtering methods have been proposed that attempt to effectively remove these noise points from the final point cloud model. However, weak signal points have similar characteristics to noise returns, and thus can be incorrectly eliminated as noise points during the filtering process. Herein, a novel voxel-spherical adaptive ellipsoid searching (VSAES) method is proposed, by which weak signal returns can be successfully retained while still removing a majority of the noise points. By employing this voxel-spherical (VS) model, our proposed method can simultaneously process a combined SPL dataset containing multiple flightlines, in which the noise density is unevenly distributed throughout the whole dataset. In addition, an improved adaptive ellipsoid searching (AES) method based on hypothesis testing is able to remove noise points more robustly than the originally described version. The experimental results show that the proposed method retains 89.1% of the weak signal point returns from electric power lines, which is a significant improvement over the performance of either to the original AES method (25.9%) or a histogram filtering based method (13.4%).
关键词： filtering,spherical voxels,single photon lidar,adaptive ellipsoid search
更新于2025-09-04 15:30:14
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Enrutamiento y asignación de longitud de onda: Nueva heurística snake-one para redes WDM bajo tráfico dinámico
摘要： In this paper is shown the simulation results of a new heuristic, called snake-one. The simulation was performed in the National Science Foundation NETwork (NSFNET-USA) under dynamic traffic and compared with other heuristics such as Simulated Annealing, Genetic Algorithms and Tabu Search previously released, using the Blocking Probability indicator and Network Utilization. Comparing these heuristics, we can observe the improvement, of the blocking up to 130 Erlangs. Nevertheless, this results mean an increased and sustained use of the network. This behavior determines a partially good result, which determines the study of a modification of the Snake-one algorithm to improve both indicators.
关键词： snake-one,Simulated annealing,genetic algorithm,tabu search
更新于2025-09-04 15:30:14