In this paper nonconservative systems are investigated within the framework of Euler Lagrange equations. The solutions of these equations are used to find the principal function S, this function is used to formulate t...In this paper nonconservative systems are investigated within the framework of Euler Lagrange equations. The solutions of these equations are used to find the principal function S, this function is used to formulate the wave function and then to quantize these systems using path integral method. One example is considered to demonstrate the application of our formalism.展开更多
Deployment of sensors in any irregular terrain with 100% coverage and connectivity is a challenging issue in the field of Wireless Sensor Networks. Traditional deployments often assume homogeneous environments, which ...Deployment of sensors in any irregular terrain with 100% coverage and connectivity is a challenging issue in the field of Wireless Sensor Networks. Traditional deployments often assume homogeneous environments, which ignore the effect of terrain profile as well as the in-network obstacles situated randomly like buildings, trees, roads and so on. Proper deployment of sensors in such irregular region and its corresponding routing is one of the most fundamental challenges of Wireless Sensor Networks. In this work, we have considered that the terrain is irregular in shape and there may be obstacles within the terrain in any random position with any random shape, which is the reality in real world. With this novel framework, we have shown that an opti-mum deployment can be achieved in such irregular terrain without compromising coverage as well as con-nectivity between the sensor nodes for effective routing.展开更多
Degradation tests are often used to assess the reliability of products with long failure-time or few test units. Much of the previous work on reliability assessment methods has focused on constant-stress degradation t...Degradation tests are often used to assess the reliability of products with long failure-time or few test units. Much of the previous work on reliability assessment methods has focused on constant-stress degradation test( CSDT) and accelerated degradation test( ADT), mainly under the constant, step or progressive stresses. However,in actual testing environments,some stresses are difficult to control and vary with time irregularly,which are quite different from the three stresses mentioned above. In this paper a new approach was presented for reliability assessment with degradation data under irregular time-varying-stress( ITVS).Firstly,the conventional degradation path modeling method was improved by taking into account the influences of the variable stress on the degradation variable. Then,an example was conducted to show the effectiveness of our improved model.展开更多
城市作战的重要性日益凸显,城市作战路径规划也受到了更多的关注。如何在城市复杂的环境和众多危险区中寻找安全迅速的路径是非常重要的。为保障作战安全,提出了一种基于选拔科特鸟和路径缩减的不规则危险区路径规划算法。首先,结合城...城市作战的重要性日益凸显,城市作战路径规划也受到了更多的关注。如何在城市复杂的环境和众多危险区中寻找安全迅速的路径是非常重要的。为保障作战安全,提出了一种基于选拔科特鸟和路径缩减的不规则危险区路径规划算法。首先,结合城市危险区特征和受限情况以构建更符合真实战场的不规则危险区数学模型。其次,建立路径空间缩减模型对路径威胁度进行评估和量化,以剔除掉高威胁路径来降低作战风险。最后,基于选拔策略的科特鸟优化算法(COOT Bird Optimization Algorithm based on Selection Strategy,SS-COOT)结合优质个体以提高算法的寻优效率。经实验验证,该算法在结合不规则危险区的城市路径规划问题上具有搜索速度快、寻优效果好的特点。展开更多
文摘In this paper nonconservative systems are investigated within the framework of Euler Lagrange equations. The solutions of these equations are used to find the principal function S, this function is used to formulate the wave function and then to quantize these systems using path integral method. One example is considered to demonstrate the application of our formalism.
文摘Deployment of sensors in any irregular terrain with 100% coverage and connectivity is a challenging issue in the field of Wireless Sensor Networks. Traditional deployments often assume homogeneous environments, which ignore the effect of terrain profile as well as the in-network obstacles situated randomly like buildings, trees, roads and so on. Proper deployment of sensors in such irregular region and its corresponding routing is one of the most fundamental challenges of Wireless Sensor Networks. In this work, we have considered that the terrain is irregular in shape and there may be obstacles within the terrain in any random position with any random shape, which is the reality in real world. With this novel framework, we have shown that an opti-mum deployment can be achieved in such irregular terrain without compromising coverage as well as con-nectivity between the sensor nodes for effective routing.
基金National Natural Science Foundations of China(Nos.61273041,71271212)
文摘Degradation tests are often used to assess the reliability of products with long failure-time or few test units. Much of the previous work on reliability assessment methods has focused on constant-stress degradation test( CSDT) and accelerated degradation test( ADT), mainly under the constant, step or progressive stresses. However,in actual testing environments,some stresses are difficult to control and vary with time irregularly,which are quite different from the three stresses mentioned above. In this paper a new approach was presented for reliability assessment with degradation data under irregular time-varying-stress( ITVS).Firstly,the conventional degradation path modeling method was improved by taking into account the influences of the variable stress on the degradation variable. Then,an example was conducted to show the effectiveness of our improved model.
文摘城市作战的重要性日益凸显,城市作战路径规划也受到了更多的关注。如何在城市复杂的环境和众多危险区中寻找安全迅速的路径是非常重要的。为保障作战安全,提出了一种基于选拔科特鸟和路径缩减的不规则危险区路径规划算法。首先,结合城市危险区特征和受限情况以构建更符合真实战场的不规则危险区数学模型。其次,建立路径空间缩减模型对路径威胁度进行评估和量化,以剔除掉高威胁路径来降低作战风险。最后,基于选拔策略的科特鸟优化算法(COOT Bird Optimization Algorithm based on Selection Strategy,SS-COOT)结合优质个体以提高算法的寻优效率。经实验验证,该算法在结合不规则危险区的城市路径规划问题上具有搜索速度快、寻优效果好的特点。