TD-CDMA中一种下行无线资源分配算法的设计

提出了一种针对TD—CDMA系统的下行无线资源分配算法,该算法能够根据用户所处的不同服务优先级别和各级别的用户个数合理地分配系统资源,而且解决了系统资源的使用效率和不同无线环境用户带宽分配的均衡问题。测试结果表明该算法是可行且有效的。     

保安电厂保安电源的完善

分析了攀钢热电厂保安电源设计配置中存在的问题，提出了相应的改进措施并加强了运行维护和管理，提高了保安电源的可靠性。     

一种面向社区型问句检索的主题翻译模型

基于统计机器翻译模型的问句检索模型,其相关性排序机制主要依赖于词项间的翻译概率,然而已有的模型没有很好地控制翻译模型的噪声,使得当前的问句检索模型存在不完善之处.文中提出一种基于主题翻译模型的问句检索模型,从理论上说明,该模型利用主题信息对翻译进行合理的约束,达到控制翻译模型噪声的效果,从而提高问句检索的结果.实验结果表明,文中提出的模型在MAP (Mean Average Precision)、MRR(Mean Reciprocal Rank)以及p@1(precision at position one)等指标上显著优于当前最先进的问句检索模型.     

Design and analysis of a frame-oriented dynamic bandwidth allocation scheme for triple-play services over EPONs

Ethernet Passive Optical Networks (EPONs) are regarded as an important technology for current access networks. However, EPONs perform poorly in differentiated service environments, and may therefore fail to meet the Quality of Service (QoS) demands of emerging triple-play services (i.e. Voice over IP, video and BE traffic). Accordingly, the present study proposes a novel Dynamic Bandwidth Allocation (DBA) scheme, designated as Frame-Oriented Interleaved Polling with Adaptive Cycle Time (FIPACT), to improve the differentiated QoS capability of EPON networks. In the proposed scheme, the Optical Line Terminal (OLT) divides the time domain of the upstream network bandwidth into a contiguous series of fixed-length frames. Within each frame, each Optical Network Unit (ONU) is guaranteed sufficient network resources to transmit a specific quota of each triple-play service. In this manner, the proposed DBA scheme can satisfy the differentiated QoS requirements of triple-play services. Therefore, based on the M/G/1 queueing analysis framework of multiuser cyclic polling systems, this study develops an analytical framework to derive the closed-form expressions for FIPACT mean packet delay. The simulation results validate the analytical results and confirm the efficiency and effectiveness of the proposed DBA scheme.     

Mathematical Statistics and Probability Theory

The standardized difference in estimated Bayes risk between two subsets of groups of allocation variables is proposed as a test statistic for additional classification accuracy. This test is used in a minimal-best-subset algorithm that aims to select the optimal subset for the data at hand—that is, the smallest subset retaining most of the classification accuracy. A multivariate normal example confirms that all-possible-subsets and minimal-best discrimination procedures based on Wilks's lambda and Rao's test usually do not identify the best subsets according to estimated Bayes risk. The minimal-best discrimination subset was suboptimal in all of 100 bootstrapped samples: It contained too many groups in every case. In contrast, the minimal-best classification selected an optimal subset for 82 out of 100 bootstrap examples; appending a test of additional accuracy of the minimal-best subset versus the overall-best subset led to an optimal subset in the other 18 cases by suggesting the addition of more groups.     

容器云中基于改进遗传算法的资源分配策略

容器很容易针对Web应用程序提供包装、迁移和配置等服务,近年来已成为研究热点;提出了容器云中基于改进遗传算法的资源分配策略Double-GA;Double-GA是一种包括两个层次的资源分配策略:容器到虚拟机的资源分配和虚拟机到物理主机的资源分配;设计了容器云的两层资源分配的数学模型,以容器云中的整体物理主机能量消耗作为Double-GA策略的目标函数;Double-GA以遗传算法为基础,设计了双染色体的表达方式并处理好了遗传算法的初始化、进化、交叉、变异等操作;真实的实验实例数据结果表明:Double-GA双染色体算法明显优于普通遗传算法GA和递减最好适用算法。     

Nutrients and energy in proleptic branches and leaves of poplar under a short-rotation coppice

Renewable energy is often generated from biomass, produced in short-rotation coppice (SRC) cultures. These cultures are frequently established on former agricultural land with ample availability of plant nutrients as nitrogen, phosphorous, potassium, calcium and magnesium. Nevertheless, little is known about the annual recycling of these nutrients through the leaves, as well as about the amounts that are removed at harvest. We therefore quantified soil nutrient concentrations, as well as nutrient concentrations and the gross calorific value of the proleptic branches and of the leaves of 12 poplar (Populus) genotypes in the second rotation of an operational SRC (with two-year rotations). For the produced leaf biomass, we also quantified the standing energy stock and the nutrient stock of each genotype. After four years the P, K, Ca and Mg soil concentrations had not significantly changed, while the N concentration at 30–60 cm of soil depth had significantly increased. On average, the standing aboveground woody biomass of the 12 genotypes in 2013 was 13.75 Mg ha⁻¹ and the total leaf biomass was 3.54 Mg ha⁻¹. This resulted in an average standing energy stock in the leaves of 64.8 GJ ha⁻¹. Nutrient concentrations were lower in the proleptic branches as compared to the leaves, but the proleptic branches and leaf nutrient concentrations significantly varied among the genotypes.     

A travelling salesman problem with allocation, time window and precedence constraints — an application to ship scheduling

A Travelling Salesman Problem with Allocation, Time Window and Precedence Constraints (TSP-ATWPC) is considered. The TSP-ATWPC occurs as a subproblem of optimally sequencing a given set of port visits in a real bulk ship scheduling problem, which is a combined multi-ship pickup and delivery problem with time windows and multi-allocation problem. Each ship in the fleet is equipped with a flexible cargo hold that can be partitioned into several smaller holds in a given number of ways, thus allowing multiple products to be carried simultaneously by the same ship. The allocation constraints of the TSP-ATWPC ensure that the partition of the ship's flexible cargo hold and the allocation of cargoes to the smaller holds are feasible throughout the visiting sequence. The TSP-ATWPC is solved as a shortest path problem on a graph whose nodes are the states representing the set of nodes in the path, the last visited node and the accumulated cargo allocation. The arcs of the graph represent transitions from one state to another. The algorithm is a forward dynamic programming algorithm. A number of domination and elimination tests are introduced to reduce the state space. The computational results show that the proposed algorithm for the TSP-ATWPC works, and optimal solutions are obtained to the real ship scheduling problem.     

Synthesis of water networks for industrial parks considering inter-plant allocation

Since an industrial park is a cluster of multiple company individuals, there is requirement to develop specific reuse strategies so as to improve the utilization of resources across plants. This article presents a ‘plant-based’ mode respecting to the water allocation problem within industrial parks. In the mode, mixers and splitters are involved to present the mixing, conveying and splitting operations for reusing streams across plants. Such that, the mixing possibilities can also be investigated and many redundant solutions can be avoided by considering the number limit of inter-plant stream connections at the building stage of network superstructures. On base of this mode, both direct and mixed (direct–indirect) integration scenarios are studied in this study. Superstructures are established and mathematically formulated aiming to minimum fresh water consumption as well as the total annualized cost. At last, three integration cases are explored based on an example from literature for illustration.     

基于LDA主题模型的社会网络链接预测

针对传统社会网络链接预测方法忽视节点文本内容的问题,提出一种基于潜在狄利克雷分配(Latent Dirichlet Allocation, LDA)主题模型的协作演化链接预测算法。算法利用LDA模型,对节点的文本内容进行分析,提取出每个节点的主题分布向量,利用分布向量的点积来衡量节点文本的相似性;然后将节点文本内容相似性矩阵与节点邻接矩阵相加,在此基础上计算节点之间的相似性;最后选取相似性最高的k个节点作为预测结果。实验结果表明该算法在网络图稀疏的情况下有较好的效果。