为了最大化正交频分复用(orthogonal frequency division multiplexing,OFDM)无线通信系统中非实时业务的有效吞吐量,提出了一种子载波与数据包长度的联合分配(joint sub-carrier and packet size allocation,JSPSA)策略。该策略较以往...为了最大化正交频分复用(orthogonal frequency division multiplexing,OFDM)无线通信系统中非实时业务的有效吞吐量,提出了一种子载波与数据包长度的联合分配(joint sub-carrier and packet size allocation,JSPSA)策略。该策略较以往的子载波分配或数据包长度优化策略,有更大的优化自由度。基于JSPSA策略,详细分析平坦衰落信道下联合分配算法有效吞吐量函数的单调特征,证明该函数为单峰函数。利用频率选择性信道与平坦衰落信道下有效吞吐量函数单调性特征的相似性,通过引入一种新的等效信道增益,提出了一种频率选择性信道下的JSPSA算法。仿真结果表明,该算法的有效吞吐量接近于JSPSA策略下最优的枚举法,与已有的贪婪比特分配、等误比特率功率分配(greedy algorithm bit allocation/equal bit error ratio power allocation,GABA_EBPA)算法相当,而复杂度却大幅度降低,在复杂度和性能之间取得了较好的折中。展开更多
In this paper we consider a single-machine scheduling model with deteriorating jobs and simultaneous learning, and we introduce polynomial solutions for single machine makespan minimization, total flow times minimizat...In this paper we consider a single-machine scheduling model with deteriorating jobs and simultaneous learning, and we introduce polynomial solutions for single machine makespan minimization, total flow times minimization and maximum lateness minimization corresponding to the first and second special cases of our model under some agreeable conditions. However, corresponding to the third special case of our model, we show that the optimal schedules may be different from those of the classical version for the above objective functions.展开更多
This paper deals with a new class of nonlinear set valued implicit variational inclusion problems involving (A, η)-monotone mappings in 2-uniformly smooth Banach spaces. Semi-inner product structure has been used t...This paper deals with a new class of nonlinear set valued implicit variational inclusion problems involving (A, η)-monotone mappings in 2-uniformly smooth Banach spaces. Semi-inner product structure has been used to study the (A, η)-monotonicity. Using the generalized resolvent operator technique and the semi-inner product structure, the approximation solvability of the proposed problem is investigated. An iterative algorithm is constructed to approximate the solution of the problem. Convergence analysis of the proposed algorithm is investigated. Similar results are also investigated for variational inclusion problems involving (H, η)-monotone mappings.展开更多
Experimental investigation and numerical modeling on elasto-plastic notch-root stress/strain distributions under monotonic loadings of both the Ni-based directionally solidified(DS)superalloy and Titanium alloy were c...Experimental investigation and numerical modeling on elasto-plastic notch-root stress/strain distributions under monotonic loadings of both the Ni-based directionally solidified(DS)superalloy and Titanium alloy were carried out simultaneously.For measuring inhomogeneous deformation fields at notch roots,an optical-numerical full-field surface deformation measurement system was developed based on the digital image correlation(DIC)method.The obtained strain distributions were then verified with reasonable accuracy by finite element simulation,where an anisotropic elastic-viscoplastic constitutive model was developed for DS superalloy and a simple isotropic stress-strain relationship was adopted for Titanium alloy.Meanwhile,factors affecting elasto-plastic notch-root stress/strain distributions were systematically investigated numerically,where the emphasis was placed on temperature,loading stress rate,sample shape,anisotropy and notch features.The results show that stress/strain behavior at notch root is significantly affected by the mentioned factors,which are concretely embodied in the distribution of tensile stress/strain,equivalent stress and accumulative equivalent plastic strain.展开更多
文摘为了最大化正交频分复用(orthogonal frequency division multiplexing,OFDM)无线通信系统中非实时业务的有效吞吐量,提出了一种子载波与数据包长度的联合分配(joint sub-carrier and packet size allocation,JSPSA)策略。该策略较以往的子载波分配或数据包长度优化策略,有更大的优化自由度。基于JSPSA策略,详细分析平坦衰落信道下联合分配算法有效吞吐量函数的单调特征,证明该函数为单峰函数。利用频率选择性信道与平坦衰落信道下有效吞吐量函数单调性特征的相似性,通过引入一种新的等效信道增益,提出了一种频率选择性信道下的JSPSA算法。仿真结果表明,该算法的有效吞吐量接近于JSPSA策略下最优的枚举法,与已有的贪婪比特分配、等误比特率功率分配(greedy algorithm bit allocation/equal bit error ratio power allocation,GABA_EBPA)算法相当,而复杂度却大幅度降低,在复杂度和性能之间取得了较好的折中。
文摘In this paper we consider a single-machine scheduling model with deteriorating jobs and simultaneous learning, and we introduce polynomial solutions for single machine makespan minimization, total flow times minimization and maximum lateness minimization corresponding to the first and second special cases of our model under some agreeable conditions. However, corresponding to the third special case of our model, we show that the optimal schedules may be different from those of the classical version for the above objective functions.
文摘This paper deals with a new class of nonlinear set valued implicit variational inclusion problems involving (A, η)-monotone mappings in 2-uniformly smooth Banach spaces. Semi-inner product structure has been used to study the (A, η)-monotonicity. Using the generalized resolvent operator technique and the semi-inner product structure, the approximation solvability of the proposed problem is investigated. An iterative algorithm is constructed to approximate the solution of the problem. Convergence analysis of the proposed algorithm is investigated. Similar results are also investigated for variational inclusion problems involving (H, η)-monotone mappings.
基金supported by the National Natural Science Foundation of China(Grant No.51275023)the Innovation Foundation of BUAA for PhD Graduates(Grant No.YWF-14-YJSY-49)
文摘Experimental investigation and numerical modeling on elasto-plastic notch-root stress/strain distributions under monotonic loadings of both the Ni-based directionally solidified(DS)superalloy and Titanium alloy were carried out simultaneously.For measuring inhomogeneous deformation fields at notch roots,an optical-numerical full-field surface deformation measurement system was developed based on the digital image correlation(DIC)method.The obtained strain distributions were then verified with reasonable accuracy by finite element simulation,where an anisotropic elastic-viscoplastic constitutive model was developed for DS superalloy and a simple isotropic stress-strain relationship was adopted for Titanium alloy.Meanwhile,factors affecting elasto-plastic notch-root stress/strain distributions were systematically investigated numerically,where the emphasis was placed on temperature,loading stress rate,sample shape,anisotropy and notch features.The results show that stress/strain behavior at notch root is significantly affected by the mentioned factors,which are concretely embodied in the distribution of tensile stress/strain,equivalent stress and accumulative equivalent plastic strain.