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MCWOA Scheduler:Modified Chimp-Whale Optimization Algorithm for Task Scheduling in Cloud Computing 被引量:1
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作者 Chirag Chandrashekar Pradeep Krishnadoss +1 位作者 Vijayakumar Kedalu Poornachary Balasundaram Ananthakrishnan 《Computers, Materials & Continua》 SCIE EI 2024年第2期2593-2616,共24页
Cloud computing provides a diverse and adaptable resource pool over the internet,allowing users to tap into various resources as needed.It has been seen as a robust solution to relevant challenges.A significant delay ... Cloud computing provides a diverse and adaptable resource pool over the internet,allowing users to tap into various resources as needed.It has been seen as a robust solution to relevant challenges.A significant delay can hamper the performance of IoT-enabled cloud platforms.However,efficient task scheduling can lower the cloud infrastructure’s energy consumption,thus maximizing the service provider’s revenue by decreasing user job processing times.The proposed Modified Chimp-Whale Optimization Algorithm called Modified Chimp-Whale Optimization Algorithm(MCWOA),combines elements of the Chimp Optimization Algorithm(COA)and the Whale Optimization Algorithm(WOA).To enhance MCWOA’s identification precision,the Sobol sequence is used in the population initialization phase,ensuring an even distribution of the population across the solution space.Moreover,the traditional MCWOA’s local search capabilities are augmented by incorporating the whale optimization algorithm’s bubble-net hunting and random search mechanisms into MCWOA’s position-updating process.This study demonstrates the effectiveness of the proposed approach using a two-story rigid frame and a simply supported beam model.Simulated outcomes reveal that the new method outperforms the original MCWOA,especially in multi-damage detection scenarios.MCWOA excels in avoiding false positives and enhancing computational speed,making it an optimal choice for structural damage detection.The efficiency of the proposed MCWOA is assessed against metrics such as energy usage,computational expense,task duration,and delay.The simulated data indicates that the new MCWOA outpaces other methods across all metrics.The study also references the Whale Optimization Algorithm(WOA),Chimp Algorithm(CA),Ant Lion Optimizer(ALO),Genetic Algorithm(GA)and Grey Wolf Optimizer(GWO). 展开更多
关键词 Cloud computing SCHEDULING chimp optimization algorithm whale optimization algorithm
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A Deep-Learning and Transfer-Learning Hybrid Aerosol Retrieval Algorithm for FY4-AGRI:Development and Verification over Asia
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作者 Disong Fu Hongrong Shi +9 位作者 Christian AGueymard Dazhi Yang Yu Zheng Huizheng Che Xuehua Fan Xinlei Han Lin Gao Jianchun Bian Minzheng Duan Xiangao Xia 《Engineering》 SCIE EI CAS CSCD 2024年第7期164-174,共11页
The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral b... The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral bands,enabling the detection of highly variable aerosol optical depth(AOD).Quantitative retrieval of AOD has hitherto been challenging,especially over land.In this study,an AOD retrieval algorithm is proposed that combines deep learning and transfer learning.The algorithm uses core concepts from both the Dark Target(DT)and Deep Blue(DB)algorithms to select features for the machinelearning(ML)algorithm,allowing for AOD retrieval at 550 nm over both dark and bright surfaces.The algorithm consists of two steps:①A baseline deep neural network(DNN)with skip connections is developed using 10 min Advanced Himawari Imager(AHI)AODs as the target variable,and②sunphotometer AODs from 89 ground-based stations are used to fine-tune the DNN parameters.Out-of-station validation shows that the retrieved AOD attains high accuracy,characterized by a coefficient of determination(R2)of 0.70,a mean bias error(MBE)of 0.03,and a percentage of data within the expected error(EE)of 70.7%.A sensitivity study reveals that the top-of-atmosphere reflectance at 650 and 470 nm,as well as the surface reflectance at 650 nm,are the two largest sources of uncertainty impacting the retrieval.In a case study of monitoring an extreme aerosol event,the AGRI AOD is found to be able to capture the detailed temporal evolution of the event.This work demonstrates the superiority of the transfer-learning technique in satellite AOD retrievals and the applicability of the retrieved AGRI AOD in monitoring extreme pollution events. 展开更多
关键词 Aerosol optical depth Retrieval algorithm Deep learning Transfer learning Advanced Geosynchronous Radiation IMAGER
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血清HMGA2、P-gp与老年进展性脑梗死患者预后相关研究 被引量:1
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作者 孙一鸣 王翠 +2 位作者 尹文超 徐晓琳 付煜颖 《疑难病杂志》 CAS 2024年第5期542-547,共6页
目的探讨血清高迁移率族蛋白A2(HMGA2)、P-糖蛋白(P-gp)在老年进展性脑梗死患者中的表达水平及其与预后的关系。方法收集2020年2月—2023年2月大连市中心医院神经内科收治老年进展性脑梗死患者67例为进展组,老年非进展性脑梗死患者79例... 目的探讨血清高迁移率族蛋白A2(HMGA2)、P-糖蛋白(P-gp)在老年进展性脑梗死患者中的表达水平及其与预后的关系。方法收集2020年2月—2023年2月大连市中心医院神经内科收治老年进展性脑梗死患者67例为进展组,老年非进展性脑梗死患者79例为非进展组;进展组根据治疗后3个月神经功能恢复情况分为预后良好亚组(n=39,mRS评分0~2分)和预后不良亚组(n=28,mRS评分3~6分)。采用酶联免疫吸附法检测血清HMGA2、P-gp水平,Pearson积矩相关分析血清HMGA2、P-gp与NIHSS评分的关系,Logistic回归分析进展性脑梗死患者预后不良的影响因素,受试者工作特征曲线(ROC)评估血清HMGA2、P-gp对预后不良的预测价值。结果进展组血清HMGA2、P-gp水平及NIHSS评分高于非进展组(t/P=13.672/<0.001,8.095/<0.001,8.226/<0.001)。进展性脑梗死患者血清HMGA2、P-gp与NIHSS评分均呈正相关(r/P=0.732/<0.001、0.708/<0.001);预后不良亚组患者年龄大于预后良好亚组,血清HMGA2、P-gp水平及NIHSS评分高于预后良好亚组(t/P=5.092/<0.001、5.103/<0.001、4.449/<0.001、2.357/0.021)。多因素Logistic回归结果显示,高龄和血清HMGA2、P-gp水平及NIHSS评分升高是进展性脑梗死患者预后不良独立危险因素[OR(95%CI)=1.429(1.093~1.869),1.288(1.082~1.533),1.586(1.161~2.165),1.483(1.120~1.963)];血清HMGA2、P-gp及二者联合预测进展性脑梗死患者预后不良的AUC分别为0.738、0.740、0.895,二者联合优于各自单独预测效能(Z/P=2.031/0.002、2.006/0.003)。结论血清HMGA2、P-gp在老年进展性脑梗死患者中异常升高,并与病情严重程度以及预后不良有关,早期联合检测两项指标可预测患者预后不良风险发生。 展开更多
关键词 进展性脑梗死 高迁移率族蛋白A2 p-糖蛋白 神经功能缺损评分 预后 老年人
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基于P-犹豫模糊集与VIKOR的绿色产品设计多属性决策方法
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作者 鲍宏 李红真 +2 位作者 刘天赐 柯庆镝 张俊国 《计算机集成制造系统》 EI CSCD 北大核心 2024年第10期3492-3501,共10页
针对绿色产品设计属性不确定及其关联关系的复杂性问题,提出一种基于P-犹豫模糊集与多准则妥协解排序(VIKOR)法的绿色产品设计多属性决策方法。利用Pythagorean犹豫模糊数度量产品属性及其特征值得到专家初始权重;考虑绿色设计决策者及... 针对绿色产品设计属性不确定及其关联关系的复杂性问题,提出一种基于P-犹豫模糊集与多准则妥协解排序(VIKOR)法的绿色产品设计多属性决策方法。利用Pythagorean犹豫模糊数度量产品属性及其特征值得到专家初始权重;考虑绿色设计决策者及属性关联,运用λ-模糊测度、Shapley值和交叉熵得到决策者及属性关联权重;以综合最大化整体效用和最小化个体遗憾为目标,基于VIKOR法对绿色产品设计方案进行排序选择;最后通过实例分析验证方法的合理性和有效性。研究结果显示,该方法既可以综合绿色设计决策者心理,有效区分不同绿色设计方案之间的差别,又可以描述绿色设计决策者和属性间的关联关系,为绿色产品设计多属性决策提供了一种可行的方法。 展开更多
关键词 p-犹豫模糊集 VIKOR方法 绿色产品设计 多属性决策
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Primal-Dual Interior-Point Algorithms with Dynamic Step-Size Based on Kernel Functions for Linear Programming 被引量:3
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作者 钱忠根 白延琴 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期391-396,共6页
In this paper, primal-dual interior-point algorithm with dynamic step size is implemented for linear programming (LP) problems. The algorithms are based on a few kernel functions, including both serf-regular functio... In this paper, primal-dual interior-point algorithm with dynamic step size is implemented for linear programming (LP) problems. The algorithms are based on a few kernel functions, including both serf-regular functions and non-serf-regular ones. The dynamic step size is compared with fixed step size for the algorithms in inner iteration of Newton step. Numerical tests show that the algorithms with dynaraic step size are more efficient than those with fixed step size. 展开更多
关键词 linear programming (LP) interior-point algorithm small-update method large-update method.
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Direct P-code acquisition algorithm based on bidirectional overlap technique 被引量:1
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作者 Ying Xu Lijuan Xu +1 位作者 Hong Yuan Ruidan Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期538-546,共9页
According to the signal-to-noise ratio (SNR) loss of average algorithms in direct P-code acquisition method, this paper analyzes the SNR performance of the overlap average algorithm quantitatively, and derives the r... According to the signal-to-noise ratio (SNR) loss of average algorithms in direct P-code acquisition method, this paper analyzes the SNR performance of the overlap average algorithm quantitatively, and derives the relationship of SNR loss with overlap shift value and initial average phase difference in the overlap average algorithm. On this basis, the bidirectional overlap average algorithm based on optimal correlation SNR is proposed. The algorithm maintains SNR consistent in the entire initial average phase difference space, and has a better SNR performance than the overlap average algorithm. The effectiveness of the algorithm is verified by both theoretical analysis and simulation results. The SNR performance of the bidirectional overlap average algorithm is 5 dB better than that of the direct average algorithm, and 2 dB better than that of the overlap average algorithm, which provides the support for direct P-code acquisition in low SNR. 展开更多
关键词 p-CODE direct acquisition direct average algorithm bidirectional overlap algorithm.
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Research and Application on Web Information Retrieval Based on Improved FP-Growth Algorithm 被引量:2
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作者 JIAO Minghai YAN Ping JIANG Huiyan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1065-1068,共4页
A kind of single linked lists named aggregative chain is introduced to the algorithm, thus improving the architecture of FP tree. The new FP tree is a one-way tree and only the pointers that point its parent at each n... A kind of single linked lists named aggregative chain is introduced to the algorithm, thus improving the architecture of FP tree. The new FP tree is a one-way tree and only the pointers that point its parent at each node are kept. Route information of different nodes in a same item are compressed into aggregative chains so that the frequent patterns will be produced in aggregative chains without generating node links and conditional pattern bases. An example of Web key words retrieval is given to analyze and verify the frequent pattern algorithm in this paper. 展开更多
关键词 data mining CHAINS Fp-growth algorithm frequent pattern aggregative information retrieval
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Simplified p-norm-like Constraint LMS Algorithm for Efficient Estimation of Underwater Acoustic Channels 被引量:8
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作者 F.Y. Wu Y.H. Zhou +1 位作者 F. Tong R. Kastner 《Journal of Marine Science and Application》 2013年第2期228-234,共7页
Underwater acoustic channels are recognized for being one of the most difficult propagation media due to considerable difficulties such as: multipath, ambient noise, time-frequency selective fading. The exploitation ... Underwater acoustic channels are recognized for being one of the most difficult propagation media due to considerable difficulties such as: multipath, ambient noise, time-frequency selective fading. The exploitation of sparsity contained in underwater acoustic channels provides a potential solution to improve the performance of underwater acoustic channel estimation. Compared with the classic 10 and 11 norm constraint LMS algorithms, the p-norm-like (Ip) constraint LMS algorithm proposed in our previous investigation exhibits better sparsity exploitation performance at the presence of channel variations, as it enables the adaptability to the sparseness by tuning of p parameter. However, the decimal exponential calculation associated with the p-norm-like constraint LMS algorithm poses considerable limitations in practical application. In this paper, a simplified variant of the p-norm-like constraint LMS was proposed with the employment of Newton iteration m to approximate the decimal exponential calculation. Num simulations and the experimental results obtained in physical shallow water channels demonstrate the effectiveness of the proposed method compared to traditional norm constraint LMS algorithms. 展开更多
关键词 p-norm-like constraint tmderwater acoustic channels LMS algorithm sparsity exploitation
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CNOP-P-based parameter sensitivity for double-gyre variation in ROMS with simulated annealing algorithm 被引量:3
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作者 YUAN Shijin ZHANG Huazhen +1 位作者 LI Mi MU Bin 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期957-967,共11页
Reducing the error of sensitive parameters by studying the parameters sensitivity can reduce the uncertainty of the model,while simulating double-gyre variation in Regional Ocean Modeling System(ROMS).Conditional Nonl... Reducing the error of sensitive parameters by studying the parameters sensitivity can reduce the uncertainty of the model,while simulating double-gyre variation in Regional Ocean Modeling System(ROMS).Conditional Nonlinear Optimal Perturbation related to Parameter(CNOP-P)is an effective method of studying the parameters sensitivity,which represents a type of parameter error with maximum nonlinear development at the prediction time.Intelligent algorithms have been widely applied to solving Conditional Nonlinear Optimal Perturbation(CNOP).In the paper,we proposed an improved simulated annealing(SA)algorithm to solve CNOP-P to get the optimal parameters error,studied the sensitivity of the single parameter and the combination of multiple parameters and verified the effect of reducing the error of sensitive parameters on reducing the uncertainty of model simulation.Specifically,we firstly found the non-period oscillation of kinetic energy time series of double gyre variation,then extracted two transition periods,which are respectively from high energy to low energy and from low energy to high energy.For every transition period,three parameters,respectively wind amplitude(WD),viscosity coefficient(VC)and linear bottom drag coefficient(RDRG),were studied by CNOP-P solved with SA algorithm.Finally,for sensitive parameters,their effect on model simulation is verified.Experiments results showed that the sensitivity order is WD>VC>>RDRG,the effect of the combination of multiple sensitive parameters is greater than that of single parameter superposition and the reduction of error of sensitive parameters can effectively reduce model prediction error which confirmed the importance of sensitive parameters analysis. 展开更多
关键词 parameter sensitivity DOUBLE GYRE Regional Ocean Modeling System(ROMS) CONDITIONAL Nonlinear Optimal Perturbation(CNOp-P) simulated annealing(SA)algorithm
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Determination of the Thermodynamic Properties of Water and Steam in the p-T and p-S Planes via Different Grid Search Computer Algorithms 被引量:2
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作者 Dugang Guo 《Fluid Dynamics & Materials Processing》 EI 2019年第4期419-430,共12页
The role of different grid search computer algorithms for the determination of the thermodynamic properties of water and steam in the p-T and P-S planes has been investigated via experimental and analytical methods.Th... The role of different grid search computer algorithms for the determination of the thermodynamic properties of water and steam in the p-T and P-S planes has been investigated via experimental and analytical methods.The results show that the spline interpolation grid search algorithm and the power grid search algorithm are more efficient,stable and clear than other algorithms. 展开更多
关键词 GRID algorithm WATER STEAM THERMODYNAMICS
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Step-coordination Algorithm of Traffic Control Based on Multi-agent System 被引量:1
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作者 Hai-Tao Zhang Fang Yu Wen Li 《International Journal of Automation and computing》 EI 2009年第3期308-313,共6页
Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes tra... Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system (MAS) is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study. 展开更多
关键词 Traffic control coordination algorithm multi-agent system (MAS) traffic control system agent.
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Elevator Group-Control Policy Based on Neural Network Optimized by Genetic Algorithm 被引量:1
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作者 沈虹 万健如 +2 位作者 张志超 刘英培 李光叶 《Transactions of Tianjin University》 EI CAS 2009年第4期245-248,共4页
Aiming at the diversity and nonlinearity of the elevator system control target, an effective group method based on a hybrid algorithm of genetic algorithm and neural network is presented in this paper. The genetic alg... Aiming at the diversity and nonlinearity of the elevator system control target, an effective group method based on a hybrid algorithm of genetic algorithm and neural network is presented in this paper. The genetic algorithm is used to search the weight of the neural network. At the same time, the multi-objective-based evaluation function is adopted, in which there are three main indicators including the passenger waiting time, car passengers number and the number of stops. Different weights are given to meet the actual needs. The optimal values of the evaluation function are obtained, and the optimal dispatch control of the elevator group control system based on neural network is realized. By analyzing the running of the elevator group control system, all the processes and steps are presented. The validity of the hybrid algorithm is verified by the dynamic imitation performance. 展开更多
关键词 elevator group control genetic algorithm neural network hybrid algorithm
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基于P-中心模型的城市轨道交通线网应急救援站选址研究 被引量:1
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作者 吴莹 陆愈实 《城市轨道交通研究》 北大核心 2024年第9期80-86,共7页
[目的]随着城市轨道交通线网的扩大,其系统风险变得更为复杂且不可控。为提高城市轨道交通系统的应急救援能力,需对线网内应急救援站的选址问题展开研究。[方法]将地铁覆盖区域按照城市道路环线进行分区限速,得到任意路径的速度矩阵,结... [目的]随着城市轨道交通线网的扩大,其系统风险变得更为复杂且不可控。为提高城市轨道交通系统的应急救援能力,需对线网内应急救援站的选址问题展开研究。[方法]将地铁覆盖区域按照城市道路环线进行分区限速,得到任意路径的速度矩阵,结合距离矩阵进行转换后得到时间矩阵。在此基础上,计算任意站点间基于时间的最短路径。考虑时间、救援关系、成本3个方面的约束条件,建立了以系统最大救援时间最小化为目标的P-中心选址模型。以武汉市城市轨道交通线网应急救援站选址为案例,应用该模型,并采用自适应遗传算法在MATLAB软件中进行编程求解,得出该线网应急救援站选址的最优方案。[结果及结论]与相似研究相比,该选址方案投入更少但效益更大,充分证明了所提的P-中心模型具有先进性。 展开更多
关键词 城市轨道交通 线网 应急救援站选址 p-中心模型 自适应遗传算法
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基于DGLPP-SVDD算法的化工过程故障检测 被引量:1
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作者 孙四通 李师庆 《化工自动化及仪表》 CAS 2024年第2期310-318,共9页
为解决传统全局局部保留投影算法(GLPP)不能充分利用已有故障数据进行特征提取的缺点,提出了判别全局局部保留投影算法(DGLPP)。在数据降维处理后,为应对高斯和非高斯混合分布的过程数据特性,通过支持向量数据描述算法(SVDD)构建故障检... 为解决传统全局局部保留投影算法(GLPP)不能充分利用已有故障数据进行特征提取的缺点,提出了判别全局局部保留投影算法(DGLPP)。在数据降维处理后,为应对高斯和非高斯混合分布的过程数据特性,通过支持向量数据描述算法(SVDD)构建故障检测统计量。将两种算法相结合提出基于DGLPP-SVDD的故障检测方法。将DGLPP-SVDD算法应用于TE过程仿真,并与GLPP算法对比,结果表明:DGLPP-SVDD算法具有更短的故障检测滞后时间和更高的故障检测率。 展开更多
关键词 特征提取 DGLPp-SVDD算法 图嵌入 故障检测 全局局部保留投影 支持向量数据描述
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采用改进BP-PID控制的机器人避障仿真研究 被引量:1
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作者 吴静松 耿振铎 《中国工程机械学报》 北大核心 2024年第4期437-441,共5页
针对移动机器人避障过程中行驶路径长、寻路速度慢等问题,提出了一种改进反向传播-比例-积分-微分(BP-PID)控制器,并对移动机器人避障效果进行仿真验证。利用移动机器人在二维坐标系的避障简图,得出了移动机器人运动方程式。引用比例-积... 针对移动机器人避障过程中行驶路径长、寻路速度慢等问题,提出了一种改进反向传播-比例-积分-微分(BP-PID)控制器,并对移动机器人避障效果进行仿真验证。利用移动机器人在二维坐标系的避障简图,得出了移动机器人运动方程式。引用比例-积分-微分(PID)控制器和3层BP神经网络结构,利用BP神经网络的学习能力调整PID控制器参数。引用粒子群算法进行改进,通过改进粒子群算法在线优化BP-PID控制器,确保移动机器人BP-PID控制器收敛于全局最优值,从而使移动机器人避障效果更好。在不同环境中,采用Matlab软件对移动机器人避障效果进行仿真,比较改进前和改进后的移动机器人避障效果。结果显示:在不同环境中,改进前和改进后的BP-PID控制器均能使移动机器人安全地躲避障碍物;但是采用改进的粒子群算法优化BP-PID控制器,可以使移动机器人运动路径更短,迭代次数更少,搜索时间更短。采用改进BP-PID控制器,能够提高移动机器人避障过程中寻路速度,缩短行驶路径,效果更好。 展开更多
关键词 移动机器人 BP神经网络 PID控制器 改进粒子群算法 避障 仿真
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Modified Self-adaptive Immune Genetic Algorithm for Optimization of Combustion Side Reaction of p-Xylene Oxidation 被引量:1
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作者 陶莉莉 孔祥东 +1 位作者 钟伟民 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1047-1052,共6页
In recent years, immune genetic algorithm (IGA) is gaining popularity for finding the optimal solution for non-linear optimization problems in many engineering applications. However, IGA with deterministic mutation fa... In recent years, immune genetic algorithm (IGA) is gaining popularity for finding the optimal solution for non-linear optimization problems in many engineering applications. However, IGA with deterministic mutation factor suffers from the problem of premature convergence. In this study, a modified self-adaptive immune genetic algorithm (MSIGA) with two memory bases, in which immune concepts are applied to determine the mutation parameters, is proposed to improve the searching ability of the algorithm and maintain population diversity. Performance comparisons with other well-known population-based iterative algorithms show that the proposed method converges quickly to the global optimum and overcomes premature problem. This algorithm is applied to optimize a feed forward neural network to measure the content of products in the combustion side reaction of p-xylene oxidation, and satisfactory results are obtained. 展开更多
关键词 self-adaptive immune genetic algorithm artificial neural network measurement p-xylene oxidation process
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基于P-糖蛋白信号通路研究龙血竭对大鼠失重空肠屏障损伤的保护机制 被引量:1
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作者 张瀚文 刘珊 +2 位作者 潘秋霞 张波 李玉娟 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第5期546-552,共7页
传统中药龙血竭在航天肠道损伤的防护中发挥重要作用,但其保护失重屏障损伤的作用机制尚不清楚.P-糖蛋白(P-glycoprotein,P-gp)是肠上皮细胞膜上的外排转运体,能够将毒素、有害菌等外排以维持肠屏障完整性.文中采用大鼠尾吊模型模拟微... 传统中药龙血竭在航天肠道损伤的防护中发挥重要作用,但其保护失重屏障损伤的作用机制尚不清楚.P-糖蛋白(P-glycoprotein,P-gp)是肠上皮细胞膜上的外排转运体,能够将毒素、有害菌等外排以维持肠屏障完整性.文中采用大鼠尾吊模型模拟微重力效应,灌胃给药龙血竭(Dragon’s Blood,DB)21d后,观察大鼠空肠组织形态、测定肠屏障通透性标志物质量浓度、检测P-gp与Wnt/β-Catenin信号通路相关蛋白的表达.结果表明,龙血竭可通过激活Wnt/β-Catenin信号通路促进空肠中P-gp基因及蛋白的表达,能够缓解模拟微重力效应下的大鼠空肠屏障损伤.研究结果或可为航天员在轨肠道损伤防护提供基础研究数据. 展开更多
关键词 龙血竭(DB) 微重力 空肠屏障 p-糖蛋白 WNT/Β-CATENIN信号通路
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ACS algorithm-based adaptive fuzzy PID controller and its application to CIP-I intelligent leg 被引量:2
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作者 谭冠政 窦红权 《Journal of Central South University of Technology》 2007年第4期528-536,共9页
Based on the ant colony system (ACS) algorithm and fuzzy logic control, a new design method for optimal fuzzy PID controller was proposed. In this method, the ACS algorithm was used to optimize the input/output scal... Based on the ant colony system (ACS) algorithm and fuzzy logic control, a new design method for optimal fuzzy PID controller was proposed. In this method, the ACS algorithm was used to optimize the input/output scaling factors of fuzzy PID controller to generate the optimal fuzzy control rules and optimal real-time control action on a given controlled object. The designed controller, called the Fuzzy-ACS PID controller, was used to control the CIP-Ⅰ intelligent leg. The simulation experiments demonstrate that this controller has good control performance. Compared with other three optimal PID controllers designed respectively by using the differential evolution algorithm, the real-coded genetic algorithm, and the simulated annealing, it was verified that the Fuzzy-ACS PID controller has better control performance. Furthermore, the simulation results also verify that the proposed ACS algorithm has quick convergence speed, small solution variation, good dynamic convergence behavior, and high computation efficiency in searching for the optimal input/output scaling factors. 展开更多
关键词 PID controller fuzzy control ACS algorithm optimal control input/output scaling factors
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基于天牛须优化算法和LP-SWT-SVD的鲁棒图像水印技术
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作者 吴捷 刘振兴 马小虎 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第5期45-52,共8页
为了有效保护数字媒体的知识产权,提出一种基于拉普拉斯金字塔和平稳小波变换(Stationary Wavelet Transform,SWT)及奇异值分解(Singular Value Decomposition,SVD)的图像水印嵌入算法。该算法首先对原始图像进行拉普拉斯金字塔分解,然... 为了有效保护数字媒体的知识产权,提出一种基于拉普拉斯金字塔和平稳小波变换(Stationary Wavelet Transform,SWT)及奇异值分解(Singular Value Decomposition,SVD)的图像水印嵌入算法。该算法首先对原始图像进行拉普拉斯金字塔分解,然后对得到的残差图像进行一级平稳小波变换,得到低频子带LL1和高频子带HH1,分别对其进行SVD分解,并将SVD分解后的水印分别嵌入低频和高频子带的奇异值矩阵中,使用天牛须算法(Beetle Antennae Search,BAS)优化水印嵌入过程。水印检测时,将从LL1和HH1子带中提取的水印进行比较,选择效果较好的作为最终结果。仿真实验与其他文献的对比分析证明该算法不可见性和鲁棒性都较好。 展开更多
关键词 拉普拉斯金字塔 平稳小波变换 奇异值分解 天牛须算法
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Solving DCLAP-MSN based on hybrid genetic algorithm
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作者 Hongtao Lei Bo Guo Tao Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期806-811,共6页
The dynamic capacitated location allocation problem in the military supportive network(DCLAP-MSN) is a representative of combinative optimization problems,and its optimization process is complicated.For this reason,... The dynamic capacitated location allocation problem in the military supportive network(DCLAP-MSN) is a representative of combinative optimization problems,and its optimization process is complicated.For this reason,a dynamic capacitated location allocation model is provided firstly.Then,a hybrid heuristic algorithm which combines genetic algorithm,repair algorithm of solutions and greedy search,is proposed as the solving method.The optimization performance is improved by effectively integrating the repair algorithm of solutions and greedy search with genetic optimization.The experiment results indicate that the proposed algorithm is a feasible and effective method for the problem. 展开更多
关键词 dynamic location allocation military supportive network genetic algorithm repair algorithm greedy search.
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