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A FUNCTION NODE-BASED MULTIPLE PAIRWISE KEYS MANAGEMENT PROTOCOL FOR WIRELESS SENSOR NETWORKS AND ENERGY CONSUMPTION ANALYSIS
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作者 Bi Jiana Wang Hui Sun Yandong Liu Yanzhao Ji Zhenzhou 《Journal of Electronics(China)》 2009年第5期692-698,共7页
In this letter, a Function node-based Multiple Pairwise Keys Management (MPKMF) protocol for Wireless Sensor Networks (WSNs) is firstly designed, in which ordinary nodes and cluster head nodes are responsible for data... In this letter, a Function node-based Multiple Pairwise Keys Management (MPKMF) protocol for Wireless Sensor Networks (WSNs) is firstly designed, in which ordinary nodes and cluster head nodes are responsible for data collection and transmission, and function nodes are responsible for key management. There are more than one function nodes in the cluster consulting the key generation and other security decision-making. The function nodes are the second-class security center because of the characteristics of the distributed WSNs. Secondly, It is also described that the formation of function nodes and cluster heads under the control of the former, and five kinds of keys, i.e., individual key, pairwise keys, cluster key, management key, and group key. Finally, performance analysis and experiments show that, the protocol is superior in communication and energy consumption. The delay of establishing the cluster key meets the requirements, and a multiple pairwise key which adopts the coordinated security authentication scheme is provided. 展开更多
关键词 Wireless Sensor Networks (WSNs) function nodes Key management Energy consumption
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The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function,atrio-ventricular node function and hemodynamics
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作者 Jingming Zhu Ningning Hui Xiuhong Jiang Huaxing Zhang Chengzhang Fu 《Journal of Nanjing Medical University》 2007年第6期386-389,共4页
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function, atrio-ventricular node function and hemodynamics. Methods:Thirty-two Angora' s rabbits were selected and randomly divide... Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function, atrio-ventricular node function and hemodynamics. Methods:Thirty-two Angora' s rabbits were selected and randomly divided into four groups. U1 group:urapidil 0.25 mg/kg; U2 group:urapidil 0.5 mg/kg; N1 group:nicardipine 10 μg/kg; N2 group: nicardipine 20 μg/kg. All these medicine were administrated within 30 seconds. Measurements were taken before and after the administration of urapidil or nicardipine for the following data: mean blood pressure(MAP), heart rate(HR), sino-atrial conduction time(SACT), maximal sinoatrial recovery time(SNRTmax) corrected sinus node recovery time(CSNRT), index of sinus node recovery time(SNRTI), Wenckebach A-V conduction frequency (WB), and P-R interval. Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine. No significant changes could be found in the rest of the parameters. Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P 〈 0.01); the MAP decreased(P 〈 0.01) and the HR increased drastically(P〈 0.01). Conclusions:Neither urapidil(0.25 mg/kg, 0,5 mg/kg) nor nicardipine(10 μg/kg, 20 μg/kg) has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function. Nicardipine could be a better choice than urapidil for parafunctional sinus node patients. 展开更多
关键词 URAPIDIL NICARDIPINE sinus function A-V node function HEMODYNAMICS
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Extracting Multiple Nodes in a Brain Region of Interest for Brain Functional Network Estimation and Classification
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作者 Chengcheng Wang Haimei Wang +1 位作者 Yifan Qiao Yining Zhang 《Journal of Applied Mathematics and Physics》 2022年第11期3408-3423,共16页
Purpose: Brain functional networks (BFNs) has become important approach for diagnosis of some neurological or psychological disorders. Before estimating BFN, obtaining blood oxygen level dependent (BOLD) representativ... Purpose: Brain functional networks (BFNs) has become important approach for diagnosis of some neurological or psychological disorders. Before estimating BFN, obtaining blood oxygen level dependent (BOLD) representative signals from brain regions of interest (ROIs) is important. In the past decades, the common method is generally to take a ROI as a node, averaging all the voxel time series inside it to extract a representative signal. However, one node does not represent the entire information of this ROI, and averaging method often leads to signal cancellation and information loss. Inspired by this, we propose a novel model extraction method based on an assumption that a ROI can be represented by multiple nodes. Methods: In this paper, we first extract multiple nodes (the number is user-defined) from the ROI based on two traditional methods, including principal component analysis (PCA), and K-means (Clustering according to the spatial position of voxels). Then, canonical correlation analysis (CCA) was issued to construct BFNs by maximizing the correlation between the representative signals corresponding to the nodes in any two ROIs. Finally, to further verify the effectiveness of the proposed method, the estimated BFNs are applied to identify subjects with autism spectrum disorder (ASD) and mild cognitive impairment (MCI) from health controls (HCs). Results: Experimental results on two benchmark databases demonstrate that the proposed method outperforms the baseline method in the sense of classification performance. Conclusions: We propose a novel method for obtaining nodes of ROId based on the hypothesis that a ROI can be represented by multiple nodes, that is, to extract the node signals of ROIs with K-means or PCA. Then, CCA is used to construct BFNs. 展开更多
关键词 Brain functional Network node Selection Pearson’s Correlation Canonical Correlation Analysis Brain Disorder Classification
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An Approximation Algorithm for the solution of astrophysics equations using rational scaled generalized Laguerre function collocation method based on transformed Hermite-Gauss nodes
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作者 Ali Pirkhedri Parisa Daneshjoo +3 位作者 Hamid Haj Seyyed Javadi Hamid Navidi Salem Khodamoradi Kamal Ghaderi 《International Journal of Astronomy and Astrophysics》 2011年第2期67-72,共6页
In this paper we propose a collocation method for solving Lane-Emden type equation which is nonlinear or-dinary differential equation on the semi-infinite domain. This equation is categorized as singular initial value... In this paper we propose a collocation method for solving Lane-Emden type equation which is nonlinear or-dinary differential equation on the semi-infinite domain. This equation is categorized as singular initial value problems. We solve this equation by the generalized Laguerre polynomial collocation method based on Her-mite-Gauss nodes. This method solves the problem on the semi-infinite domain without truncating it to a fi-nite domain and transforming domain of the problem to a finite domain. In addition, this method reduces so-lution of the problem to solution of a system of algebraic equations. 展开更多
关键词 Lane-Emden equation GENERALIZED Laguerre functions Collocation method Hermite-Gauss nodeS Nonlinear ODE SEMI-INFINITE
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Coupling Magneto-Electro-Elastic node-based smoothed radial point interpolation method for free vibration and transient analysis of Functionally Graded Magneto-Electro-Elastic structures 被引量:2
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作者 Liming ZHOU Shuhui REN +2 位作者 Bin NIE Guikai GUO Xiangyang CUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期227-243,共17页
A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(F... A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(FGMEE)structures.By introducing the modified Newmark method,the displacement,electrical potential and magnetic potential of the structures under transient mechanical loading were obtained.Based on G space theory and the weakened weak(W2)formulation,the equations of the multi-physics coupling problems were derived.Using triangular background elements,the free vibration and transient responses of three numerical examples were studied.Results proved that CM-NS-RPIM performed better than the standard FEM by reducing the overly-stiff of structures.Moreover,CM-NS-RPIM could reduce the number of nodes while guaranteeing the accuracy.Besides,triangular elements could be generated automatically even for complex geometries.Therefore,the effectiveness and validity of CM-NS-RPIM were demonstrated,which were valuable for the design of intelligence devices,such as energy harvesters and sensors. 展开更多
关键词 COUPLING MAGNETO-ELECTRO-ELASTIC node-based smoothed radial point interpolation method functionally Graded MAGNETO-ELECTRO-ELASTIC Gradient smoothing technique Rayleigh damping Transient responses
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基于复杂网络的流域水网关键节点识别与功能通道分类研究
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作者 李发文 铁倩如 《水资源保护》 北大核心 2026年第1期39-48,共10页
针对流域水网关键节点与通道的系统分类和定量识别问题,基于复杂网络理论,构建了融合度中心性、中介中心度和特征向量中心性的综合评估体系,提出控制-可达二维分类矩阵,分类识别了我国四大流域(海河、黄河、淮河、长江流域)水网结构中... 针对流域水网关键节点与通道的系统分类和定量识别问题,基于复杂网络理论,构建了融合度中心性、中介中心度和特征向量中心性的综合评估体系,提出控制-可达二维分类矩阵,分类识别了我国四大流域(海河、黄河、淮河、长江流域)水网结构中的关键节点与功能通道。结果表明:淮河流域核心枢纽型通道占比22.02%,海河流域高等级节点占比56.87%,均体现出明显的控制集中特征;黄河流域中等过渡型通道占比高达88.10%,表现为结构均衡但缺乏强控制通道;长江流域边缘隔离型通道比例为14.45%,凸显复杂地形下的通达性不足。 展开更多
关键词 复杂网络 水网结构 关键节点 功能通道 海河流域 黄河流域 淮河流域 长江流域
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不同切口的病灶清除术联合功能性颈淋巴结清扫对颈部淋巴结核患者术后颈部活动度的影响
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作者 李梦瑶 赵珺玥 +1 位作者 周鹏 王天晓 《中国医刊》 2026年第3期314-317,共4页
目的探究小切口与常规切口病灶清除术联合功能性颈淋巴结清扫(FND)对颈部淋巴结核患者术后颈部活动度的影响。方法本研究为回顾性研究,选取南京市中西医结合医院2023年1月至2024年12月收治的80例颈部淋巴结核患者,根据手术切口的不同分... 目的探究小切口与常规切口病灶清除术联合功能性颈淋巴结清扫(FND)对颈部淋巴结核患者术后颈部活动度的影响。方法本研究为回顾性研究,选取南京市中西医结合医院2023年1月至2024年12月收治的80例颈部淋巴结核患者,根据手术切口的不同分为小切口组(37例)和常规组(43例),小切口组接受小切口病灶清除术联合FND治疗,常规组接受常规切口病灶清除术联合FND治疗。比较两组的治疗效果、围手术期指标、颈部活动度及并发症发生率。结果两组治疗总有效率比较差异无统计学意义(P>0.05)。小切口组手术时间、切口长度短于常规组,术中出血量、术后24 h引流量少于常规组,切口愈合时间及住院时间短于常规组,差异均有统计学意义(P<0.05)。小切口组术后1个月颈部前屈、后伸、左旋、右旋活动度均大于常规组,差异有统计学意义(P<0.05)。两组术后并发症发生率比较差异无统计学意义(P>0.05)。结论小切口病灶清除术联合FND治疗颈部淋巴结核可减轻手术损伤,缩短恢复时间,患者术后早期颈部活动度恢复更佳,且疗效与常规切口手术相当。 展开更多
关键词 小切口病灶清除术 功能性颈淋巴结清扫 颈部淋巴结核 治疗效果 颈部活动度
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融合改进A^(*)与DWA算法的机器人路径规划
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作者 谢德瀚 高金凤 +3 位作者 贾国强 李乐宝 苏雯 梅从立 《电子科技》 2026年第1期64-72,96,共10页
针对传统A^(*)算法拓展节点冗余、路径贴近障碍物以及传统DWA(Dynamic Window Approaches)算法轨迹振荡、易陷入局部极小值等问题,文中提出了一种融合改进A^(*)与DWA算法的机器人路径规划方法。改进传统A^(*)算法代价函数去除了冗余拓... 针对传统A^(*)算法拓展节点冗余、路径贴近障碍物以及传统DWA(Dynamic Window Approaches)算法轨迹振荡、易陷入局部极小值等问题,文中提出了一种融合改进A^(*)与DWA算法的机器人路径规划方法。改进传统A^(*)算法代价函数去除了冗余拓展节点,改进子节点选取策略避免了路径贴近障碍物,并通过双向平滑度优化去除不必要转折点。在DWA算法评价函数中引入自适应距离因子以减少轨迹的振荡,将A^(*)先验路径离散节点作为DWA算法的局部目标点进行算法融合。仿真实验表明,改进A^(*)算法拓展节点减少了118个,规划时间减少了29.9%,改进DWA算法规划速度提高了5.3%。所提融合算法能够在保障路径全局最优的同时避免陷入局部极小值,实现了对未知障碍物的实时避障。 展开更多
关键词 机器人 路径规划 A^(*)算法 DWA算法 启发函数 子节点选取 双向平滑度优化 距离因子
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基于热模拟实验的煤化作用跃变分子结构演化规律研究
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作者 李鹏鹏 王安民 +7 位作者 冯一乙 王盛剑 何文婷 曾培林 冯思锦 鲍政宇 宾祥慎 初奕然 《煤质技术》 2026年第1期12-19,共8页
为从分子层面揭示煤化作用跃变特点,以新疆伊犁低阶煤样为实验样品,在250~600℃温度区间开展热模拟实验,运用傅里叶变换红外光谱(FTIR)与X射线衍射(XRD)技术,系统分析热模拟实验前后的煤分子结构演化特征。结果表明:热模拟实验共模拟出... 为从分子层面揭示煤化作用跃变特点,以新疆伊犁低阶煤样为实验样品,在250~600℃温度区间开展热模拟实验,运用傅里叶变换红外光谱(FTIR)与X射线衍射(XRD)技术,系统分析热模拟实验前后的煤分子结构演化特征。结果表明:热模拟实验共模拟出煤化作用的前3次跃变。第一次跃变发生于R_(o)≈0.6%附近,其特征为脂肪族侧链长度(CH_(2)/CH_(3))降低,多类含氧官能团(芳香醚C—O—C、酚醚C—O、酯C—O—C、脂肪醚C—O—C和醇类C—O)含量占比升高,而羟基(—OH)与羰基(C=O)含量显著下降。与此同时,芳香片层间距(d_(002))、延展度(L_(a))、堆砌高度(L_(c))与堆砌层数(N_(ave))均出现不同程度的降低,反映出大量脂肪族侧链和不稳定含氧基团发生热解脱落,推动煤进入第一次煤化跃变阶段,与生烃起始点一致。第二次跃变出现在R_(o)≈1.4%左右,此阶段含氧官能团含量有所增加,而—OH、C=O以及脂肪族CH_(2)和CH_(3)则持续减少。对应的d_(002)明显减小,而L_(a)与L_(c)稳步上升,表明芳构化反应开始占据主导地位,脂肪结构向芳香结构的转化加速。第三次跃变位于R_(o)≈2.3%附近,其特征为多类含氧官能团含量下降,而—OH、羰基C=O及脂肪族CH_(2)、CH_(3)含量占比相对上升;同时d_(002)、L_(a)、L_(c)与N_(ave)均出现下降。该阶段反映煤化作用进入以缩聚反应为主的高级演化阶段。 展开更多
关键词 煤化作用跃变 分子结构 跃变节点 热模拟 含氧官能团
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Precision surgical approach with lymph-node dissection in early gastric cancer 被引量:30
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作者 Shinichi Kinami Naohiko Nakamura +4 位作者 Yasuto Tomita Takashi Miyata Hideto Fujita Nobuhiko Ueda Takeo Kosaka 《World Journal of Gastroenterology》 SCIE CAS 2019年第14期1640-1652,共13页
The gravest prognostic factor in early gastric cancer is lymph-node metastasis,with an incidence of about 10% overall. About two-thirds of early gastric cancer patients can be diagnosed as node-negative prior to treat... The gravest prognostic factor in early gastric cancer is lymph-node metastasis,with an incidence of about 10% overall. About two-thirds of early gastric cancer patients can be diagnosed as node-negative prior to treatment based on clinicpathological data. Thus, the tumor can be resected by endoscopic submucosal dissection. In the remaining third, surgical resection is necessary because of the possibility of nodal metastasis. Nevertheless, almost all patients can be cured by gastrectomy with D1+ lymph-node dissection. Laparoscopic or robotic gastrectomy has become widespread in East Asia because perioperative and oncological safety are similar to open surgery. However, after D1+ gastrectomy,functional symptoms may still result. Physicians must strive to minimize postgastrectomy symptoms and optimize long-term quality of life after this operation.Depending on the location and size of the primary lesion, preservation of the pylorus or cardia should be considered. In addition, the extent of lymph-node dissection can be individualized, and significant gastric-volume preservation can be achieved if sentinel node biopsy is used to distinguish node-negative patients.Though the surgical treatment for early gastric cancer may be less radical than in the past, the operative method itself seems to be still in transition. 展开更多
关键词 STOMACH neoplasms SURGERY GASTRECTOMY methods Recovery of function SENTINEL LYMPH node SURGERY Gastric cancer
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Health-related quality of life evaluated by tumor node metastasis staging system in patients with hepatocellular carcinoma 被引量:11
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作者 Cui-Xia Qiao Xiao-Feng Zhai +4 位作者 Chang-Quan Ling Qing-Bo Lang Hui-Juan Dong Qun Liu Mou-Duo Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第21期2689-2694,共6页
AIM: To investigate and evaluate the change in healthrelated quality of life (HRQoL) by tumor node metastasis (TNM) staging system in patients with hepatocellular carcinoma (HCC). METHODS: A total of 140 patients diag... AIM: To investigate and evaluate the change in healthrelated quality of life (HRQoL) by tumor node metastasis (TNM) staging system in patients with hepatocellular carcinoma (HCC). METHODS: A total of 140 patients diagnosed with HCC between June 2008 and April 2009 in our department were enrolled to this study. One hundred and thirty-five (96.5%) patients had liver cirrhosis secondary to hepatitis B virus (HBV) infection, 73 (54.07%) of them being HBV DNA positive; the other etiologies of liver cirrhosis were alcoholic liver disease (1.4%), hepatitis C (1.4%) or cryptogenic (0.7%). All subjects were fully aware of their diagnosis and provided informed consent. HRQoL was assessed before treatment using the functional assessment of cancer therapy-hepatobiliary (FACT-Hep) questionnaire. Descriptive statistics were used to evaluate demographics and disease-specific characteristics of the patients. One-way analysis of variance and independent samples t tests were used to compare the overall FACT-Hep scores and clinically distinct TNM stages. Scores for all FACT-Hep items were analyzed by frequency analyses. The mean scores obtained from the FACT-Hep in different Child-Pugh classes were also evaluated. RESULTS: The mean FACT-Hep scores were reduced significantly from TNM StageⅠto Stage Ⅱ, Stage ⅢA, Stage ⅢB group (687 ± 39.69 vs 547 ± 42.57 vs 387 ± 51.24 vs 177 ± 71.44, P = 0.001). Regarding the physical and emotional well-being subscales, scores decreased gradually from Stage Ⅰ to Stage ⅢB (P = 0.002 vs Stage Ⅰ; P = 0.032 vs Stage Ⅱ; P = 0.033 vs Stage ⅢA). Mean FACT-Hep scores varied by Child-Pugh class, especially in the subscales of physical well-being, functional well-being and the hepatobiliary cancer (P = 0.001 vs Stage I; P = 0.036 vs Stage Ⅱ; P = 0.032 vs Stage ⅢA). For the social and family well-being subscale, only Stage ⅢB scores were significantly lower as compared with Stage Ⅰ scores (P = 0.035). For the subscales of functional well-being and hepatobiliary cancer, there were significant differences for Stages ⅡΙ, ⅢA and ⅢB (P = 0.002vs StageⅠ). CONCLUSION: HRQoL of patients with HCC worsens gradually with progression of TNM stages. The most impaired subscales of HRQoL, as measured by FACT-Hep, were physical and emotional well-being. 展开更多
关键词 Hepatocellular carcinoma Tumor node metastasis staging functional assessment of cancer therapy-hepatobiliary Health-related quality of life Cross-sectional study
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Evidential method to identify influential nodes in complex networks 被引量:7
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作者 Hongming Mo Cai Gao Yong Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期381-387,共7页
Identifying influential nodes in complex networks is still an open issue. In this paper, a new comprehensive centrality mea- sure is proposed based on the Dempster-Shafer evidence theory. The existing measures of degr... Identifying influential nodes in complex networks is still an open issue. In this paper, a new comprehensive centrality mea- sure is proposed based on the Dempster-Shafer evidence theory. The existing measures of degree centrality, betweenness centra- lity and closeness centrality are taken into consideration in the proposed method. Numerical examples are used to illustrate the effectiveness of the proposed method. 展开更多
关键词 Dempster-Shafer evidence theory (D-S theory) belief function complex networks influential nodes evidential centrality comprehensive measure
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多障碍环境下巡检机器人路径规划优化研究 被引量:7
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作者 乔道迹 张艳兵 《现代电子技术》 北大核心 2025年第1期130-134,共5页
针对大规模、密集的障碍物分布,高效地搜索最佳路径是一个挑战,为规划出更短的巡检路线,并实现多障碍环境下的灵活避障,文中提出一种多障碍环境下巡检机器人路径规划优化方法。使用二维矩阵构建巡检环境模型,应用D*算法在巡检环境模型... 针对大规模、密集的障碍物分布,高效地搜索最佳路径是一个挑战,为规划出更短的巡检路线,并实现多障碍环境下的灵活避障,文中提出一种多障碍环境下巡检机器人路径规划优化方法。使用二维矩阵构建巡检环境模型,应用D*算法在巡检环境模型中进行巡检机器人路径规划,并将传统D*算法中的扩展步长方式改变为自适应扩展步长,使机器人在面积较大的巡检场地能够更快地完成巡检;将代价函数由欧氏距离替换为切比雪夫诺距离和曼哈顿距离融合的代价函数,并引入了平滑度函数优化线路规划结果,使规划的路径更为平滑,在遇到由于多种原因产生的新障碍物时可以重新规划路径。通过实验结果可知,无论是静态地图还是动态地图,该方法均可以快速准确地规划出一条最佳路线,并且在多种环境中应用该方法能够高效获取路径规划结果。 展开更多
关键词 多障碍 巡检机器人 路径规划 D*算法 动态环境 扩展节点 代价函数 扩展步长
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国际航空网络社区结构探测及枢纽节点挖掘
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作者 秦昆 邢玲丽 +3 位作者 喻雪松 梁天祺 周扬 乔治浩 《同济大学学报(自然科学版)》 北大核心 2025年第12期1904-1914,共11页
采用2013―2022年的官方航空指南(Official Aviation Guide,OAG)数据,以国家/地区为节点、以节点之间的航空交通量为边构建加权国际航空网络(International Aviation Network,IAN)。通过Louvain算法识别IAN中的社区,并进一步分析其时空... 采用2013―2022年的官方航空指南(Official Aviation Guide,OAG)数据,以国家/地区为节点、以节点之间的航空交通量为边构建加权国际航空网络(International Aviation Network,IAN)。通过Louvain算法识别IAN中的社区,并进一步分析其时空演变规律;在社区探测的基础上,基于社区内z分数和参与系数挖掘结构性枢纽,基于核心度挖掘功能性枢纽。研究结果表明,IAN具有小世界特性,呈现多模块格局,自然地理、国际地缘政治等均对社区的形成产生影响;IAN在社区层面具有异质性,其特性反映了各社区有差异的航空合作模式;IAN社区结构整体稳定,但政治博弈等突发事件会导致社区结构发生变化;在IAN中,结构性枢纽约占5.0%,功能性枢纽约占7.6%。 展开更多
关键词 国际航空网络 社区结构 Louvain算法 结构性枢纽 功能性枢纽
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基于障碍密度优先策略改进A^(*)算法的AGV路径规划 被引量:4
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作者 陈一馨 段宇轩 +2 位作者 刘豪 谭世界 郑天乐 《郑州大学学报(工学版)》 北大核心 2025年第2期26-34,共9页
针对传统A^(*)算法在障碍物较多的实际场景下进行AGV路径规划时,存在路径拐点多、路径冗余节点过多以及易陷入局部最优解等问题,提出一种改进A^(*)算法,采用栅格法进行环境建模。首先,在启发函数中引入障碍物密度函数K(n)改进代价函数,... 针对传统A^(*)算法在障碍物较多的实际场景下进行AGV路径规划时,存在路径拐点多、路径冗余节点过多以及易陷入局部最优解等问题,提出一种改进A^(*)算法,采用栅格法进行环境建模。首先,在启发函数中引入障碍物密度函数K(n)改进代价函数,用于更准确地估计当前节点到目标节点的实际代价;其次,采用动态邻域搜索策略提高算法的搜索效率和运行效率;最后,通过冗余节点处理策略减少路径拐点和删除冗余节点,得到只包含起点、转折点以及终点的路径。采用不同尺寸和复杂度的栅格环境地图进行仿真实验,结果表明:所提改进A^(*)算法与传统A^(*)算法以及其他改进的A^(*)算法相比,路径长度分别缩短了4.71%和2.07%,路径拐点数量分别减少了45.45%和20.54%,路径存在节点分别减少了82.24%和62.45%。 展开更多
关键词 路径规划 栅格地图 改进A^(*)算法 启发函数 动态邻域搜索 冗余节点优化
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DUAL RECIPROCITY HYBRID BOUNDARY NODE METHOD FOR THREE-DIMENSIONAL ELASTICITY WITH BODY FORCE 被引量:3
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作者 Fei Yan Yuanhan Wang Yu Miao Fei Tan 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第3期267-277,共11页
Combining Dual Reciprocity Method (DRM) with Hybrid Boundary Node Method (HBNM), the Dual Reciprocity Hybrid Boundary Node Method (DRHBNM) is developed for three-dimensional linear elasticity problems with body ... Combining Dual Reciprocity Method (DRM) with Hybrid Boundary Node Method (HBNM), the Dual Reciprocity Hybrid Boundary Node Method (DRHBNM) is developed for three-dimensional linear elasticity problems with body force. This method can be used to solve the elasticity problems with body force without domain integral, which is inevitable by HBNM. To demonstrate the versatility and the fast convergence of this method, some numerical examples of 3-D elasticity problems with body forces are examined. The computational results show that the present method is effective and can be widely applied in solving practical engineering problems. 展开更多
关键词 hybrid boundary node method dual reciprocity method body force radial basis function
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The Next-Hop Node Selection Based GPSR in Vehicular Ad Hoc Networks
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作者 Zhaoyuan Cui Demin Li +2 位作者 Guanglin Zhang Chang Guo Yong Sheng 《Journal of Computer and Communications》 2016年第10期44-56,共13页
Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route whi... Vehicular Ad hoc Networks (VANETs) which is a special form of Mobile Ad hoc Networks (MANETs) has promising application prospects in the future. Due to the rapid changing of topology structure, how to find a route which can guarantee Quality of Service (QoS) is an important issue in VANETs. This paper presents an improved Greedy Perimeter Stateless Routing (GPSR) protocol based on our proposed next-hop node selection mechanism. Firstly, we define the link reliability in two cases which take the movement direction angle between two vehicles into consideration. Then we propose a next-hop node selection mechanism based on a weighted function which consists of link reliability between the sender node and next-hop candidate node, distance between next-hop candidate node and the destination, movement direction angle of next-hop candidate node. At last, an improved GPSR protocol is proposed based on the next-hop node selection mechanism. Simulation results are presented to evaluate the performance of the improved GPSR protocol, which shows that the performance including packet delivery ratio and average end-to-end delay of the proposed protocol is better in some situations. 展开更多
关键词 VANETS GPSR Next-Hop node Selection Link Reliability Weighted function
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基于人工鱼群算法的网络覆盖优化方法研究
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作者 汤隆 《自动化仪表》 2025年第4期97-100,106,共5页
无线传感网络随机部署移动节点时存在分布不均匀的问题,降低了网络带宽容量和网络覆盖率。为解决上述问题,基于人工鱼群算法的创新点,设计了网络覆盖优化方法。首先,分类处理不同角度的信号,设置多个基站,利用传感器的覆盖能力接收信号... 无线传感网络随机部署移动节点时存在分布不均匀的问题,降低了网络带宽容量和网络覆盖率。为解决上述问题,基于人工鱼群算法的创新点,设计了网络覆盖优化方法。首先,分类处理不同角度的信号,设置多个基站,利用传感器的覆盖能力接收信号,并确定目标函数。然后,将设置的目标函数作为训练目标,对人工鱼群算法进行预训练,并建立网络覆盖模型。最后,确定人工鱼群算法优化后的节点检测范围,以实现网络覆盖优化。试验结果表明,所提方法随着迭代次数和感知半径的增加,覆盖率逐渐稳定。所提方法能够提高网络覆盖率,并在短时间内找到最优解,从而满足设计需求。 展开更多
关键词 人工鱼群算法 无线传感网络 网络覆盖 目标函数 节点信号
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基于小生境遗传算法的网络入侵节点智能检测方法 被引量:1
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作者 王建刚 《吉林大学学报(理学版)》 北大核心 2025年第4期1099-1104,共6页
为降低网络入侵的风险,提出一种基于小生境遗传算法的网络入侵节点智能检测方法.首先,针对网络入侵的攻击行为进行聚合处理,利用双人攻防博弈模型分析网络的攻防状态,通过比对攻击与防御的效用强度,对网络的安全性进行全面分析,再根据... 为降低网络入侵的风险,提出一种基于小生境遗传算法的网络入侵节点智能检测方法.首先,针对网络入侵的攻击行为进行聚合处理,利用双人攻防博弈模型分析网络的攻防状态,通过比对攻击与防御的效用强度,对网络的安全性进行全面分析,再根据分析结果,通过卷积神经网络实现对攻击源的定位.其次,基于粗糙集理论,利用小生境遗传算法确定网络入侵节点检测的适应度函数,根据网络入侵节点智能检测规则,建立网络入侵节点智能检测模型,获得最终的检测结果.实验结果表明,该方法可有效提升对入侵攻击源的定位准确性和入侵节点检测准确性,该方法检测结果的宏F1分数大于0.96,表明该方法可有效实现设计预期. 展开更多
关键词 小生境遗传算法 网络入侵 入侵节点 粗糙集理论 适应度函数 入侵检测
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工业无线传感器网络防移动干扰攻击节点的Stackelberg博弈
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作者 孙子文 翟润华 杨晨曦 《传感技术学报》 北大核心 2025年第6期1081-1088,共8页
针对工业无线传感器网络k节点抗干扰攻击问题,研究一种抵御移动攻击节点的Stackelberg博弈模型。在攻击节点效用函数中加入以能量消耗函数、信道损耗函数和奖励收益函数为成本的代价函数,以约束节点的攻击效率。将移动Sink节点与移动攻... 针对工业无线传感器网络k节点抗干扰攻击问题,研究一种抵御移动攻击节点的Stackelberg博弈模型。在攻击节点效用函数中加入以能量消耗函数、信道损耗函数和奖励收益函数为成本的代价函数,以约束节点的攻击效率。将移动Sink节点与移动攻击节点之间的对抗交互行为建模为功率控制Stackelberg模型,通过求解博弈均衡解,给出节点移动位置下的最佳功率。MATLAB仿真结果表明,相比未引入成本代价函数的其他博弈功率控制方案,该方案能更有效地抑制移动攻击节点的干扰能力,同时提高移动k节点抵御干扰攻击的性能。 展开更多
关键词 工业无线传感器网络 STACKELBERG博弈 成本代价函数 干扰攻击 移动攻击节点
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