On L-Tychonoff spaces II

This paper is a sequel to the 1995 paper On L-Tychonoff spaces. The embedding theorem for L-topological spaces is shown to hold true for L an arbitrary complete lattice without imposing any order reversing involution (·)^′ on L. Some results on completely L-regular spaces and on L-Tychonoff spaces, which have previously been known to hold true for (L,^′) a frame, are exhibited as ones holding for (L,^′) a meet-continuous lattice. For such a lattice an insertion theorem for completely L-regular spaces is given. Some weak forms of separating families of maps are discussed. We also clarify the dependence between the sub-T₀ separation axiom of Liu and the L-T₀ separation axiom of Rodabaugh.     

Identifying codes and locating-dominating sets on paths and cycles

Let G=(V,E) be a graph and let r≥1 be an integer. For a set D⊆V, define N_r[x]={y∈V:d(x,y)≤r} and D_r(x)=N_r[x]∩D, where d(x,y) denotes the number of edges in any shortest path between x and y. D is known as an r-identifying code (r-locating-dominating set, respectively), if for all vertices x∈V (x∈V?D, respectively), D_r(x) are all nonempty and different. Roberts and Roberts [D.L. Roberts, F.S. Roberts, Locating sensors in paths and cycles: the case of 2-identifying codes, European Journal of Combinatorics 29 (2008) 72-82] provided complete results for the paths and cycles when r=2. In this paper, we provide results for a remaining open case in cycles and complete results in paths for r-identifying codes; we also give complete results for 2-locating-dominating sets in cycles, which completes the results of Bertrand et al. [N. Bertrand, I. Charon, O. Hudry, A. Lobstein, Identifying and locating-dominating codes on chains and cycles, European Journal of Combinatorics 25 (2004) 969-987].     

Optimal Channel Selection algorithm for CRahNs

As the data traffic is increasing, the spectrum bands are getting congested. It causes low latency and unreliable communication. Additional spectrum can be utilized to solve this problem but moving towards higher frequency means higher power requirement and increased cost. Cognitive radio network is another solution to this problem. It helps the nodes of a network to use the channels of the nearby bands which are not being used at that time. However, it has several challenges. One of these challenges is the transmission collision with the primary users of the network. Researchers have been working on this problem. However, it is still a major concern for the researchers. This paper proposes an algorithm that selects the optimal cognitive channel for the data transmission by the secondary user in such a way so that the transmission collision with the PU is minimized. After comparison with the existing latest similar protocol, the proposed protocol has shown 5.6% improvement in the throughput, 5.3% improvement in PDR. The delay is decreased by 0.6% and the transmission collision with PUs is reduced by 2.5%.     

Approximation by means of nonlinear Kantorovich sampling type operators in Orlicz spaces

In this paper we introduce a nonlinear version of the Kantorovich sampling type series in a nonuniform setting. By means of the above series we are able to reconstruct signals (functions) which are continuous or uniformly continuous. Moreover, we study the problem of the convergence in the setting of Orlicz spaces: this allows us to treat signals which are not necessarily continuous. Our theory applies to L^p-spaces, interpolation spaces, exponential spaces and many others. Several graphical examples are provided.     

Norm of weighted composition operators from -Bloch spaces to weighted-type spaces

We calculate in an elegant way operator norm of the weighted composition operator from the α-Bloch space, with α(0,∞){1}, to a weighted-type space on the unit ball. This result can be regarded as a complement to our recent result regarding the same problem for the case α=1.     

基于量子远程传态的无线自组织量子通信网络路由协议

针对复杂结构的无线量子通信网络,提出了无线自组织量子通信网络概念并设计其路由协议．该路由协议为按需路由协议,路由度量基于相邻节点问的纠缠粒子对数目．需要发送携带信息的量子态的节点发起路由请求和建立过程,由目的节点根据路由度量选择路径．目的节点选择路径后,沿所选路径发送路由应答信息至源节点并通知路径中其他节点．信息传输过程中,若所选路径中相邻节点问无线信道或者量子信道中断,将重新发起一个路由发现过程．建立新路由．路径中节点收到路由应答信息后,利用纠缠交换和两端逼近方法,从路径两端向中间节点方向进行纠缠交换,建立量子信道后,通过量子远程传态传输携带信息的量子态,从而实现无线自组织量子通信网络中任意两节点问信息的传递．     

可耗竭性资源从价税与累积开采量的关系研究——基于Hotelling模型的改进

提高可耗竭性资源累积开采量对解决我国资源短缺和资源开采效率低下并存的问题具有重要的意义。在增加了开采成本随累积开采量递增的假设下,本文首先对Hotelling模型做了改进。其次,运用最优控制方法,以完全竞争市场为比较基准,本文研究了垄断市场下从价税与累积开采量之间的关系。研究发现:第一,当从价税税率为零时,垄断市场下的累积开采量低于完全竞争市场下的累积开采量。第二,当从价税税率大于零时,征收从价税进一步降低了垄断市场下的累积开采量。第三,当从价税税率小于零时,征收从价税有利于提高垄断市场下的累积开采量。     

基于新型裂尖杂交元的压电材料断裂力学研究

提出了一种裂尖邻域杂交元模型,将其与标准杂交应力元结合来求解压电材料裂纹尖 端的奇性电弹场和断裂参数的数值解．裂纹尖端杂交元的建立步骤为：1) 利用高次内插有限元特征法求解特征问题,得到反映裂尖奇异性电弹场状况的特 征值和特征角分布函数;2) 利用广义Hellinger-Reissner变分泛函以及特征问题的解来建立裂尖邻域杂交元模型．该 方法求解电弹场时,摒弃了传统有限元方法中裂尖奇异性场需要借助解析解的做法,也避免 了单纯有限元方法中需要在裂尖端部进行高密度单元划分．采用PZT5板中心裂纹问题 作为考核例,数值结果显示了良好的精确性．作为进一步应用,求解了含中心界面裂纹 的PZT4-PZT5两相压电材料的应力强度因子和电位移强度因子．所有的算例都考虑 了3种裂纹面电边界条件．