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A Workflow Scheduling Method Based on the Combination of Tunicate Swarm Algorithm and Highest Response Ratio Next Scheduling
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作者 Yujie Tian Ming Zhu +2 位作者 Jing Li Cong Liu Ziyang Zhang 《Computers, Materials & Continua》 2026年第5期1950-1963,共14页
Workflow scheduling is critical for efficient cloud resource management.This paper proposes Tunicate Swarm-Highest Response Ratio Next,a novel scheduler that synergistically combines the Tunicate Swarm Algorithm with ... Workflow scheduling is critical for efficient cloud resource management.This paper proposes Tunicate Swarm-Highest Response Ratio Next,a novel scheduler that synergistically combines the Tunicate Swarm Algorithm with the Highest Response Ratio Next policy.The Tunicate Swarm Algorithm generates a cost-minimizing task-to-VM mapping scheme,while the Highest Response Ratio Next dynamically dispatches tasks in the ready queue with the highest-priority.Experimental results demonstrate that the Tunicate Swarm-Highest Response RatioNext reduces costs by up to 94.8%compared to meta-heuristic baselines.It also achieves competitive cost efficiency vs.a learning-based method while offering superior operational simplicity and efficiency,establishing it as a highly practical solution for dynamic cloud environments. 展开更多
关键词 Workflow scheduling cloud computing tunicate swarm algorithm highest response ratio next scheduling
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Blind recognition of polar code parameters based on log-likelihood ratio
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作者 ZHONG Zhaogen XIE Cunxiang JIN Kun 《Journal of Systems Engineering and Electronics》 2025年第3期642-658,共17页
The syndrome a posteriori probability of the log-likelihood ratio of intercepted codewords is used to develop an algorithm that recognizes the polar code length and generator matrix of the underlying polar code.Based ... The syndrome a posteriori probability of the log-likelihood ratio of intercepted codewords is used to develop an algorithm that recognizes the polar code length and generator matrix of the underlying polar code.Based on the encoding structure,three theorems are proved,two related to the relationship between the length and rate of the polar code,and one related to the relationship between frozen-bit positions,information-bit positions,and codewords.With these three theorems,polar codes can be quickly reconstruced.In addition,to detect the dual vectors of codewords,the statistical characteristics of the log-likelihood ratio are analyzed,and then the information-and frozen-bit positions are distinguished based on the minimumerror decision criterion.The bit rate is obtained.The correctness of the theorems and effectiveness of the proposed algorithm are validated through simulations.The proposed algorithm exhibits robustness to noise and a reasonable computational complexity. 展开更多
关键词 code length frozen-bit position information-bit position log-likelihood ratio polar code
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Optimization of the reflux ratio of benzene-toluene stage distillation columns by the Cuckoo algorithm 被引量:1
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作者 Bahador Abolpour Ali Mohebbi 《Petroleum Science》 SCIE CAS CSCD 2014年第3期446-453,共8页
In this study, an enthalpy-concentration method was applied in order to model a steady state continuous benzene-toluene mixture distillation column. For a distillation tower such as the benzene- toluene splitter, ther... In this study, an enthalpy-concentration method was applied in order to model a steady state continuous benzene-toluene mixture distillation column. For a distillation tower such as the benzene- toluene splitter, there are relatively few degrees of freedom that can be manipulated in order to minimize the total annualized cost. The reflux ratio can influence the steady-state operating point and therefore influence the total annualized cost. The trade-offs between reflux ratios and total annualized cost were discussed. The Cuckoo optimization algorithm was applied to obtain a correlation for the optimum value of the reflux ratio as a power function of the economic parameters of energy price and capital cost. The results show that, at low energy price or high capital cost, the optimum reflux factor is high. 展开更多
关键词 Benzene-toluene mixture distillation column Cuckoo optimization algorithm optimized reflux ratio total annualized cost
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Operational Mode Identification Based on Sliding Time Window Method and Eigensystem Realization Algorithm
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作者 WANG Liang ZHANG Yan +1 位作者 CAI Yipeng NANGONG Zijun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第5期838-844,共7页
The identification result of operational mode is eurychoric while operational mode identification is investigated under ambient excitation,which is influenced by the signal size and the time interval.The operational m... The identification result of operational mode is eurychoric while operational mode identification is investigated under ambient excitation,which is influenced by the signal size and the time interval.The operational mode identification method,which is based on the sliding time window method and the eigensystem realization algorithm(ERA),is investigated to improve the identification accuracy and stability.Firstly,the theory of the ERA method is introduced.Secondly,the strategy for decomposition and implementation is put forward,including the sliding time window method and the filtration method of modes.At last,an example is studied,where the model of a cantilever beam is built and the white noise exciting is input.Results show that the operational mode identification method can realize the modes,and has high robustness to the signal to noise ratio and signal size. 展开更多
关键词 mode identification ROBUST eigensystem realization algorithm(ERA) operational mode damping ratio
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Multiobjective Reptile Search Algorithm Based Effective Image Deblurring and Restoration 被引量:1
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作者 G.S.Yogananda J.Ananda Babu 《Journal of Artificial Intelligence and Technology》 2023年第4期154-161,共8页
Images are frequently affected because of blurring,and data loss occurred by sampling and noise occurrence.The images are getting blurred because of object movement in the scenario,atmospheric misrepresentations,and o... Images are frequently affected because of blurring,and data loss occurred by sampling and noise occurrence.The images are getting blurred because of object movement in the scenario,atmospheric misrepresentations,and optical aberrations.The main objective of image restoration is to evaluate the original image from the corrupted data.To overcome this issue,the multiobjective reptile search algorithm is proposed for performing an effective image deblurring and restoration(MORSA-IDR).The proposed MORSA is used in two different processes such as threshold and kernel parameter calculation.In that,threshold values are used for detecting and replacing the noisy pixel removal using deep residual network,and estimation of kernel is performed for deblurring the images.The main objective of the proposed MORSA-IDR is to enhance the process of deblurring for recovering low-level contextual information.The MORSA-IDR is evaluated using peak signal noise ratio(PSNR)and structural similarity index.The existing researches such as enhanced local maximum intensity(ELMI)prior and deep unrolling for blind deblurring(DUBLID)are used to evaluate the MORSA-IDR.The PSNR of MORSA-IDR for image 6 is 30.98 dB,which is high when compared with the ELMI and DUBLID. 展开更多
关键词 deep residual network estimation of kernel image deblurring and restoration multiobjective reptile search algorithm noisy pixel removal peak signal to noise ratio
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Development and application of the mo-ment-ratio imaging algorithm
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作者 黄建平 马丽 张晁军 《Acta Seismologica Sinica(English Edition)》 CSCD 2006年第5期569-580,共12页
In the moment-ratio imaging algorithm, which is based on the theory of healing of a wound, the energy of each strong earthquake is distributed around the epicenter according to certain rules, and the features of the M... In the moment-ratio imaging algorithm, which is based on the theory of healing of a wound, the energy of each strong earthquake is distributed around the epicenter according to certain rules, and the features of the Moment-ratio value R are analyzed as the space and time change, so that the relationships between the moment-ration value R and strong earthquakes can be found. In the present paper, regions divided, hypocenter depths and events completed magnitude analyses were carried out in the Chinese catalogue. By applying the moment-ratio imaging algorithm in which the parameters are adjusted, the processes of anomaly evolution which correspond to the epicenter and the surrounding value R before earthquakes of M≥7.0 since 1966 in different areas of China were analyzed. It was found that the range area and imminent time of a coming earthquake could be confirmed quantita- tively by analyzing the abnormal temporal and spatial variation of the value R The results showed that the temporal and spatial variation of the value R could quantitatively reflect the temporal and spatial factors of a coming strong earthquake as well as the rule of medium rupture. 展开更多
关键词 moment-ratio imaging algorithm healing quantitative analysis China strong earthquakes
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SPQ:An Improved Q Algorithm Based on Slot Prediction
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作者 Jiacheng Luo Jiahao Wen Jian Yang 《Computer Systems Science & Engineering》 2025年第1期301-316,共16页
Mitigating tag collisions is paramount for enhancing throughput in Radio Frequency Identification(RFID)systems.However,traditional algorithms encounter challenges like slot wastage and inefficient frame length adjustm... Mitigating tag collisions is paramount for enhancing throughput in Radio Frequency Identification(RFID)systems.However,traditional algorithms encounter challenges like slot wastage and inefficient frame length adjustments.To tackle these challenges,the Slot Prediction Q(SPQ)algorithm was introduced,integrating the VogtII prediction algorithm and slot grouping to improve the initial Q value by predicting the first frame.This method quickly estimates the number of tags based on slot utilization,accelerating Q value adjustments when slot utilization is low.Furthermore,a Markov decision chain is used to optimize the relationship between the number of slot groupings(x)and the Q value.The Whale Optimization Algorithm(WOA)is applied to fine-tune the learning rate(C)and Q value in the traditional Q algorithm.Simulation results demonstrate that SPQ significantly reduces the total slots used during the reading process and improves RFID system throughput compared to traditional Q,FastQ,Subset Enhanced Performance-Q(SUBEP-Q),and Threshold Grouping Dynamic Q(TGDQ)algorithms.Specifically,compared to the traditional Q algorithm,SPQ increases the average Identification Speed by 7.20%,System Efficiency by 11.08%,and Time Efficiency by 5.69%. 展开更多
关键词 ratio frequency identification anti-collision algorithm slot prediction Q algorithm
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Advances in dual energy computed tomography approach for proton stopping power ratio computation in radiotherapy
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作者 Charles Ekene Chika 《World Journal of Radiology》 2025年第6期24-38,共15页
To address the sensitive and uncertain limitations of single-energy computed tomography(CT)calibration methods in computing proton stopping power ratio during treatment planning,different methods have been proposed us... To address the sensitive and uncertain limitations of single-energy computed tomography(CT)calibration methods in computing proton stopping power ratio during treatment planning,different methods have been proposed using a dual energy CT approach.This paper reviews the most recent dual-energy CT approaches for computing proton stopping power ratio.These include image domain and projection domain methods.The advantages and uncertainties of these methods are analyzed based on existing studies.This paper highlights recent advances in dual energy CT,discussing their implementation,advantages,limitations,and potential for clinical adoption. 展开更多
关键词 Dual energy computed tomography Stopping power ratio Machine learning Mathematical model Image domain Projection domain RADIOTHERAPY Alternating minimization algorithm Electron density Mean excitation energy
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新型电力系统下母线比率差动保护改进算法
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作者 王风光 赵青春 +2 位作者 程骁 丁杰 龚啸 《电力工程技术》 北大核心 2026年第1期83-92,共10页
新型电力系统下,大量新能源电源及电力电子设备接入交流电网。发生母线区内故障时,受控制策略影响,故障电流幅值受控,角度受控,谐波含量高,母线比率差动保护的动作性能下降,因此文中提出一种适用于新型电力系统的母线比率差动保护改进... 新型电力系统下,大量新能源电源及电力电子设备接入交流电网。发生母线区内故障时,受控制策略影响,故障电流幅值受控,角度受控,谐波含量高,母线比率差动保护的动作性能下降,因此文中提出一种适用于新型电力系统的母线比率差动保护改进算法。首先,介绍传统比率差动算法的基本原理,并分析新型电力系统下该算法存在的问题;然后,提出不受故障电流角差及谐波影响的母线比率差动保护改进算法,将相位存在差异的各支路电流相量映射到同一坐标系下,并进行差流和制动电流计算,分析母线比率差动保护改进算法在母线区内外故障及区外故障电流互感器(current transformer,CT)饱和时的动作性能,提出母线比率差动保护改进逻辑;最后,基于实时数字仿真(real time digital simulation,RTDS),对比传统比率差动保护和改进比率差动保护的动作性能,证明改进比率差动保护能够在不降低保护动作可靠性的前提下提高动作灵敏性。 展开更多
关键词 新型电力系统 传统比率差动保护算法 改进比率差动保护算法 电流角差 制动电流 电流互感器(CT)饱和
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双向水平轴潮流能水轮机翼型优化设计
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作者 王树齐 卞百福 +1 位作者 唐吉 刘峰 《哈尔滨工程大学学报》 北大核心 2026年第1期28-34,共7页
为适应潮流能的双向性和水平轴潮流能水轮机的可靠性,本文以NACA0012翼型为基础翼型,通过截取、拼接构造完全对称翼型,并构建以翼型升阻比为优化目标的自动寻优模型。该模型基于翼型类别形状函数变换参数化方法,并结合ICEM网格划分、Flu... 为适应潮流能的双向性和水平轴潮流能水轮机的可靠性,本文以NACA0012翼型为基础翼型,通过截取、拼接构造完全对称翼型,并构建以翼型升阻比为优化目标的自动寻优模型。该模型基于翼型类别形状函数变换参数化方法,并结合ICEM网格划分、Fluent数值模拟和多岛遗传算法,最终得到适用于水平轴潮流能水轮机双向运行的高升阻比翼型。优化后的完全对称翼型相比基础翼型更加扁平,最大相对厚度减少了49.65%。同时,升力系数提高了10.77%,且升阻比提升46.24%。通过分析翼型表面压力分布,发现优化后的翼型能有效地抑制翼型吸力面的流动分离现象,使翼型整体水动性能得到大幅提升。研究成果可为水平轴潮流能水轮机叶片翼型优化研究提供参考。 展开更多
关键词 潮流能水轮机 完全对称翼型 CST参数化 多岛遗传算法 优化设计 数值模拟 升阻比 压力系数
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基于变分模态分解算法的肌电信号去噪研究
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作者 凌六一 赵博洋 +2 位作者 韦利余 刘一铭 冯彬 《蚌埠学院学报》 2026年第2期52-58,64,共8页
为了解决表面肌电(sEMG)信号采集易受环境影响,使采集到的肌电信号干扰多、噪声大的问题,提出一种变分模态分解(VMD),鲸鱼优化算法(WOA)与小波阈值去噪(WTD)相结合的方法,通过WOA优化VMD的分解参数,以实现对sEMG信号的最佳分解;然后利... 为了解决表面肌电(sEMG)信号采集易受环境影响,使采集到的肌电信号干扰多、噪声大的问题,提出一种变分模态分解(VMD),鲸鱼优化算法(WOA)与小波阈值去噪(WTD)相结合的方法,通过WOA优化VMD的分解参数,以实现对sEMG信号的最佳分解;然后利用最大相关系数法筛选出有效的分量;最后,采用WTD对筛选后的分量进一步去除噪声,并将这些分量叠加得到最终的去噪后肌电信号。通过对八组数据的对比实验可知,所提出的WOA-VMD-WTD算法不仅显著降低了sEMG信号中的高频噪声,还在信噪比改善方面,平均提升了1.97 dB。实验结果显示,在时域和频域分析中,以及在信噪比改善和均方根误差控制方面,该算法均优于其他现有方法。 展开更多
关键词 变分模态分解 鲸鱼优化算法 肌电信号 小波阈值去噪 相关系数 信噪比 均方根误差
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改进灰狼优化算法天然气余压发电参数优化
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作者 蒋林 王弘涛 +2 位作者 丁辉 朱静东 张艺馨 《煤气与热力》 2026年第3期50-55,共6页
在天然气高压差比情况下余压发电系统通常采用多级膨胀发电方式,然而中间压力选择不当和天然气入口气压波动将导致余压发电效率变低,甚至恶化发电系统的稳定性。为此,提出一种基于多策略改进灰狼优化算法的高压差比天然气余压发电参数... 在天然气高压差比情况下余压发电系统通常采用多级膨胀发电方式,然而中间压力选择不当和天然气入口气压波动将导致余压发电效率变低,甚至恶化发电系统的稳定性。为此,提出一种基于多策略改进灰狼优化算法的高压差比天然气余压发电参数优化方法。依据实例,在定工况下,使用所提算法,二级膨胀优化结果误差仅为0.041 W,三级膨胀优化结果误差仅为30 W,验证了其有效性。进一步使用所提算法在变工况下进行仿真实验,得到原工艺、变化后工况二级膨胀误差仅为0.053、0.00055 W,三级膨胀误差仅为3.7、7.8 W,验证了所提算法具有较强的工况适应性。基于多策略改进灰狼优化算法的高压差比天然气余压发电参数优化方法在定工况、变工况下优化结果误差均较小,算法的有效性和工况适应性均优良。 展开更多
关键词 多策略改进灰狼优化算法 天然气余压发电 高压差比 多级膨胀 中间压力
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Methane concentration detection system based on differential infrared absorption 被引量:1
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作者 宋林丽 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期193-196,共4页
The infrared absorption method for methane concentration detection is an ideal way to detect methane at present. However, it is difficult to spread this method due to its high cost. In this paper, by using a wideband ... The infrared absorption method for methane concentration detection is an ideal way to detect methane at present. However, it is difficult to spread this method due to its high cost. In this paper, by using a wideband infrared light emitting di- ode (LED) accompanied with a PIN photo electric diode, a low-cost methane detection system was designed. To overcome the shortcomings caused by the wide working band, a differential light path was designed. By means of a differential ratio algo- rithm, the stability and the accuracy of the system were guaranteed. Finally, the validity of the system with the proposed algo- rithm was verified by the experiment results. 展开更多
关键词 methane detection infrared absorption differential light path differential ratio algorithm
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Optimization of Linear Antenna Arrays Based on Genetic Algorithms
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作者 王宏建 高本庆 刘瑞祥 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期180-183,共4页
The methods of moment and genetic algorithm (GA) are combined to optimize the Yagi Uda antenna array and Log periodic dipole antenna (LPDA) array. The element lengths and spacing are optimized for the Yagi Uda arra... The methods of moment and genetic algorithm (GA) are combined to optimize the Yagi Uda antenna array and Log periodic dipole antenna (LPDA) array. The element lengths and spacing are optimized for the Yagi Uda array; while the ratio factor of spacing to length as well as the ratio of length to diameter of the elements are optimized for LPDA array. The results show that the main parameters, such as gain and pattern, have been improved apparently; and the high back lobe level of LPDA can be reduced greatly, therefore, GA is a very competent method for optimizing the linear array as well as in other fields. 展开更多
关键词 GAIN front to back ratio genetic algorithm OPTIMIZATION Yagi Uda antenna Log periodic dipole antenna
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新型炎症指数对老年重症心力衰竭患者近期死亡风险的预测价值:基于SHAP算法的可解释性分析
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作者 张婷 陈睿 曹文斋 《中华保健医学杂志》 2026年第1期5-10,共6页
目的 构建可解释性机器学习模型,预测老年重症心力衰竭患者短期死亡风险,并探讨新型炎症指数的预测价值。方法回顾性分析MIMIC-IV 3.1数据库中诊断为心力衰竭的老年重症患者1994例,按7∶3的比例随机分为训练集和测试集。采用6种机器学... 目的 构建可解释性机器学习模型,预测老年重症心力衰竭患者短期死亡风险,并探讨新型炎症指数的预测价值。方法回顾性分析MIMIC-IV 3.1数据库中诊断为心力衰竭的老年重症患者1994例,按7∶3的比例随机分为训练集和测试集。采用6种机器学习方法建立预测模型,包括logistic回归(LR)、决策树(DT)、随机森林(RF)、自适应增强(AdaBoost)、轻量梯度提升(LightGBM)、高斯朴素贝叶斯(NB)。模型效能通过受试者工作特征(ROC)曲线、精确率-召回率(P-R)曲线、校准曲线评估。采用SHAP进行模型解释并筛选核心炎症指数,通过ROC曲线确定最佳临界值。结果本研究共纳入1994例老年重症心力衰竭患者,28 d内死亡253例(12.7%),存活1741例(87.3%)。经初筛,纳入65个临床特征用于机器学习模型构建。结果显示LightGBM模型展现出最佳的预测性能,ROC曲线下面积(AUC)为[0.897(0.881~0.909)],P-R曲线的平均精度(AP)为0.86,校准曲线显示预测概率与实际观察结果一致。SHAP值分析揭示急性生理学评分Ⅲ(APSⅢ)、格拉斯哥昏迷评分(GCS)、单核细胞与淋巴细胞比值(MLR)、呼吸频率(RR)、年龄、血尿素氮、牛津急性疾病严重度评分(OASIS)、血管紧张素转化酶抑制剂(ACEI)、中性粒细胞与淋巴细胞比值(NLR)、营养风险指数(NRI)是重要的影响因素。ROC曲线分析MLR、NLR的AUC分别为0.682、0.667,以0.426、7.083为截断值,敏感度为0.747、0.751,特异度为0.529、0.503。结论LightGBM模型可较好地预测老年重症心力衰竭患者短期死亡风险,以NLR、MLR为代表的新型炎症指数对老年心力衰竭患者短期死亡风险分层具有潜在临床应用价值。 展开更多
关键词 心力衰竭 死亡风险 单核细胞与淋巴细胞比值 中性粒细胞与淋巴细胞比值 SHAP算法
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基于动态插值粒子群算法的VSG鲁棒性优化策略
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作者 丁文沛 刘颂凯 +3 位作者 张磊 李彦彰 艾宇坤 吴宇恒 《电网与清洁能源》 北大核心 2026年第1期13-21,共9页
针对虚拟同步发电机(virtual synchronous generator,VSG)的参数选择缺乏系统性优化方法,传统策略难以在多约束条件下兼顾动态性能与运行鲁棒性,提出一种基于动态插值粒子群算法(dynamic interpolation particle swarm optimization,DI-... 针对虚拟同步发电机(virtual synchronous generator,VSG)的参数选择缺乏系统性优化方法,传统策略难以在多约束条件下兼顾动态性能与运行鲁棒性,提出一种基于动态插值粒子群算法(dynamic interpolation particle swarm optimization,DI-PSO)的VSG鲁棒性优化策略。基于系统小信号(small signal,SS)模型构建适应度函数,通过DI-PSO结合特征值分析对VSG参数进行优化,重点解决参数选择过程中动态稳定性与多工作点适应性的协调问题。该方法在确保系统稳定裕度的前提下,利用特征值实部最小化策略提升动态响应性能,并通过电磁暂态仿真验证了优化参数在不同运行条件下的有效性。仿真结果表明,相较于传统参数整定方法,所提策略显著增强了VSG在复杂电网环境中的动态调节能力与运行弹性。 展开更多
关键词 虚拟同步发电机 小信号模型 动态插值粒子群算法 阻尼比 鲁棒性优化
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智能菜谱生成系统的研究与设计
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作者 赵光旭 廖垒 +3 位作者 郑大勇 李锐 赵金库 郑登洋 《无线互联科技》 2026年第2期69-72,共4页
针对传统烹饪食谱中食材配比不科学、模板化严重导致的个性化不足问题,文章设计了一种基于智能算法的个性化菜谱生成系统。系统通过分析用户饮食偏好与食材储备特征,实现精准的菜谱匹配与推荐。同时,文章通过结合多模态交互技术,使用户... 针对传统烹饪食谱中食材配比不科学、模板化严重导致的个性化不足问题,文章设计了一种基于智能算法的个性化菜谱生成系统。系统通过分析用户饮食偏好与食材储备特征,实现精准的菜谱匹配与推荐。同时,文章通过结合多模态交互技术,使用户可以选择描述食材需求,系统完成自动解析并生成符合营养均衡原则的多样化菜谱方案。该成果为家庭用户提供了从食材匹配到烹饪指导的全流程智能化服务,优化了传统菜谱应用的交互体验,为饮食行业的数字化转型提供了创新思路。 展开更多
关键词 多模态交互技术 多样化菜谱方案 智能算法 数字化转型
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商业三维点云空间设计尺度比例自动划分方法
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作者 阮涛 杨沙 《信息技术》 2026年第2期125-130,共6页
针对商业三维点云空间设计中尺度比例自动划分低效问题,文中提出商业三维点云空间设计尺度比例自动划分方法。通过筛选几何目标平面点云数据并拟合直线分析,修正坐标并去除干扰信息,得到商业三维点云空间的几何元素。利用OBB包围盒算法... 针对商业三维点云空间设计中尺度比例自动划分低效问题,文中提出商业三维点云空间设计尺度比例自动划分方法。通过筛选几何目标平面点云数据并拟合直线分析,修正坐标并去除干扰信息,得到商业三维点云空间的几何元素。利用OBB包围盒算法构建空间格网,规则化处理每个几何元素。定义尺度比例自动划分的目标函数,以最大化几何要素间距离和活动区域利用率为目标。利用带精英策略的非支配排序遗传算法(NSGA-Ⅱ)求解目标函数,得到尺度比例自动划分的最优方案。实验结果表明:研究方法室内有效活动空间利用率达到了72.64%。 展开更多
关键词 三维空间 点云数据 尺度比例 空间形态 NSGA-Ⅱ遗传算法
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基于ITD-K-means-小波包法的爆破振动信号降噪研究
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作者 申宇宙 张云鹏 马海越 《矿冶工程》 北大核心 2026年第1期44-50,共7页
针对实测爆破振动信号中噪声干扰的问题,提出了一种爆破振动信号降噪方法。该方法基于固有时间尺度分解(ITD)算法,将信号分解为多个IMF分量;引入K-means算法进行聚类处理,计算各类别信号的相关系数值,识别含噪信号类别;通过小波包法对... 针对实测爆破振动信号中噪声干扰的问题,提出了一种爆破振动信号降噪方法。该方法基于固有时间尺度分解(ITD)算法,将信号分解为多个IMF分量;引入K-means算法进行聚类处理,计算各类别信号的相关系数值,识别含噪信号类别;通过小波包法对含噪信号进行降噪处理并重构,得到纯净信号。采用该方法对仿真信号和实测信号进行降噪验证,结果表明,在仿真信号降噪实验中,相较于传统的小波包法、CEEMDAN法和ITD法,ITD-K-means-小波包法的信噪比(17.241 dB)最大,均方根误差(9.71×10^(-2))最小;在实测信号降噪实验中,经ITD-K-means-小波包法处理后的信号在中低频段(0~60 Hz)保留了更多的优势主频能量,有效抑制了120 Hz以上的高频噪声。 展开更多
关键词 爆破 振动信号 降噪 固有时间尺度分解(ITD) K-MEANS算法 小波包法 信噪比 仿真信号
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改进YOLOv7的高光谱图像分类研究
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作者 潘瑞远 韦小凤 《激光杂志》 北大核心 2026年第2期100-106,共7页
为了改善高光谱图像分类效果,提出了基于改进YOLOv7的高光谱图像分类方法。波段比算法计算同不同波段间相应像元的像元值之比,得到波段强度,将波段强度输入改进YOLOv7进行高光谱图像分类,通过卷积块注意模块提取通道、空间两个维度上的... 为了改善高光谱图像分类效果,提出了基于改进YOLOv7的高光谱图像分类方法。波段比算法计算同不同波段间相应像元的像元值之比,得到波段强度,将波段强度输入改进YOLOv7进行高光谱图像分类,通过卷积块注意模块提取通道、空间两个维度上的注意力机制增强后的高光谱特征图,利用上下文转换器提取包含上下文信息的高光谱图像特征图;传输至头部网络层中的Softmax分类器,将所提特征映射到分类结果,输出高光谱图像的类别信息的分类概率值,完成高光谱图像分类。研究结果显示:此方法能够在减少卷积浮点运算量的基础上,保持较高的多类型高光谱图像分类精度,分类结果的Kappa系数为1。 展开更多
关键词 改进YOLOv7 高光谱 图像分类 波段比算法 注意力机制 上下文转换器
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