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
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
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
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
由于容迟网络的间歇性连接等特点,以及节点自身缓存、能量等资源受限,DTN中的节点往往会表现出一定的自私性。自私节点的存在可能会提高网络的开销,降低消息的成功投递率。为了促进自私节点参与合作,提出了一种基于虚拟货币交易的高效...由于容迟网络的间歇性连接等特点,以及节点自身缓存、能量等资源受限,DTN中的节点往往会表现出一定的自私性。自私节点的存在可能会提高网络的开销,降低消息的成功投递率。为了促进自私节点参与合作,提出了一种基于虚拟货币交易的高效率路由算法PVCT(Efficient Routing Algorithm Based on Virtual Currency Transaction in DTN),并结合容迟网络的小世界特性,提高了路由算法的效率。该算法利用虚拟货币交易的方式,并根据节点的基本属性、位置属性、社会属性等进行定价,节点根据设计的价格函数给出对应的报价,并利用价格函数合理地分配消息副本数。在PVCT策略中,节点根据判断情况分为正常节点和自私节点,当消息的跳数小于或等于两跳时,按照概率路由的策略进行转发;反之,当消息的跳数大于两跳时,若遇到的为自私节点,则执行虚拟货币交易的路由算法。携带消息节点的出价若高于转发节点的价格,则进行交易,更新各自的收益状态;否则,进入二次价格调整阶段以协调节点双方之前的虚拟报价。仿真实验表明,PVCT路由算法在DTN中能更好地促进消息的转发,从而提升网络的整体性能。展开更多
基金Supported by the National Natural Science Foundation of China (No. 60475012)
文摘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.
文摘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.
文摘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.
文摘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.
文摘由于容迟网络的间歇性连接等特点,以及节点自身缓存、能量等资源受限,DTN中的节点往往会表现出一定的自私性。自私节点的存在可能会提高网络的开销,降低消息的成功投递率。为了促进自私节点参与合作,提出了一种基于虚拟货币交易的高效率路由算法PVCT(Efficient Routing Algorithm Based on Virtual Currency Transaction in DTN),并结合容迟网络的小世界特性,提高了路由算法的效率。该算法利用虚拟货币交易的方式,并根据节点的基本属性、位置属性、社会属性等进行定价,节点根据设计的价格函数给出对应的报价,并利用价格函数合理地分配消息副本数。在PVCT策略中,节点根据判断情况分为正常节点和自私节点,当消息的跳数小于或等于两跳时,按照概率路由的策略进行转发;反之,当消息的跳数大于两跳时,若遇到的为自私节点,则执行虚拟货币交易的路由算法。携带消息节点的出价若高于转发节点的价格,则进行交易,更新各自的收益状态;否则,进入二次价格调整阶段以协调节点双方之前的虚拟报价。仿真实验表明,PVCT路由算法在DTN中能更好地促进消息的转发,从而提升网络的整体性能。
