单箱三室连续宽箱梁有效宽度分析

箱梁在受弯时，横桥向存在剪力滞效应，为了在计算中应用初等材料力学方法求解，采用了翼缘有效宽度方法。以某实桥为背景，通过对单箱三室连续宽箱梁空间实体模型进行了有限元分析，计算得出了箱梁顶板及底板的有效分布宽度系数ρs及ρf，并与规范值进行了比较，可为同类工程设计提供参考。     

Recursive computation of the single and product moments of order statistics from the complementary exponential–geometric distribution

The complementary exponential–geometric distribution has been proposed recently as a simple and useful reliability model for analysing lifetime data. For this distribution, some recurrence relations are established for the single and product moments of order statistics. These recurrence relations enable the computation of the means, variances and covariances of all order statistics for all sample sizes in a simple and efficient recursive manner. By using these relations, we have tabulated the means, variances and covariances of order statistics from samples of sizes up to 10 for various values of the shape parameter θ. These values are in turn used to determine the best linear unbiased estimator of the scale parameter β based on complete and Type-II right-censored samples.     

How to Deal With Moral Tales: Constructions and Strategies of Single‐Parent Families

This study explored how normative understandings based on the nuclear family ideology are linked to constructions of single‐parent families and sheds light on the strategies single parents and their children adopt in dealing with negative accounts. Guided by social constructionist and configurational approaches, the in‐depth analysis is based on an Austrian qualitative study, comprising interviews with 50 ten‐year‐old children and their 71 parents, living in nuclear, reconstituted, and single‐parent families. The results showed that single‐parent families are constructed predominantly in terms of deficits and disadvantages, with the nuclear family serving as an ideological code along the dimensions of normalcy, complementarity, and stability. To deal with negative accounts, single parents and their children use three basic types of strategy: (a) imitation, (b) compensation, and (c) delimitation.     

单一经济目标下人类生存完整性的缺失与修复

单一经济目标的发展带来了人与自然、人与社会及人与人和谐关系的丧失,从而破坏了人类生存的完整性,造成了自然对人的惩罚、人的新异化的出现和经济发展的不可持续性。要修复人类生存的完整性,就必须改变单一经济目标,修复歪曲的价值等级序列,寻求经济的合理形态以及技术的生态化。     

论离异家庭子女的家庭教育策略

离异家庭的家庭结构不完整对儿童心理健康有着巨大的负面影响。使自己的孩子同完整家庭孩子一样得到健康成长,将孩子的心理灾难降低到最低限度,是每一个离异家庭家长的责任和义务。因此,家长要从家庭的解体而导致儿童存在着严重的心理问题这一角度出发,采取行之有效的家庭教育策略来面对和解决这些问题。     

基于有限优先级的动态调度算法

实时任务调度是实时系统中的关键问题,实时动态调度是实时调度的主要方面。当实时调度应用于实际的任务系统时,仅能使用有限的优先级数量。实时调度在理论分析时,都假设系统能够识别任意多的优先级。该文提出了在优先级数量有限的条件下的动态调度算法,给出了一个任务系统动态调度所需的最小优先级的数量的算法,并对算法的复杂性进行了分析。     

具单一休假的M/M/1排队模型的指数稳定性(英文)

研究具单一休假的M/M/1排队模型,使用泛函分析方法,特别是Banach空间上线性算子理论,证明了相应的动力算子的严格占优本征值的存在性,以及系统解的线性稳定性和指数稳定性.     

分布式实时嵌入式系统端到端性能确保

针对具有端到端截非周期任务模型的分布式实时系统,提出了一种ICA算法,构造了一个兼顾非周期实时任务个体性能和总体性能的分布式控制环。该算法能动态调整任务的QoS,从概率上确保了任务的端到端截止时间,并能通过确保CPU利用率来提高系统吞吐量。实验结果证明ICA能为具有端到端非周期任务模型的分布式实时嵌入式系统提供更好的性能确保。     

旋流器分离马铃薯淀粉单因素影响数学模型的研究

在马铃薯淀粉生产中,水力旋流器是淀粉分离的核心设备,选择评价水力旋流器分离性能最重的指标——分离效率,通过对影响淀粉分离效率的三个因素即底流口直径、进料压力和进料浓度进行正交实验,对实验所得结果拟合成曲线并通过图表示出来。通过对实验结果的分析获知分离马铃薯淀粉的水力旋流器的分离效率随着各参数变化的规律即单因素数学模型,得出在一定条件下的最佳分离状态的各参数值。     

The bike sharing rebalancing problem: Mathematical formulations and benchmark instances

Bike sharing systems offer a mobility service whereby public bicycles, located at different stations across an urban area, are available for shared use. These systems contribute towards obtaining a more sustainable mobility and decreasing traffic and pollution caused by car transportation. Since the first bike sharing system was installed in Amsterdam in 1965, the number of such applications has increased remarkably so that hundreds of systems are now operating all over the world.In a bike sharing system, users can take a bicycle from a station, use it to perform a journey and then leave it at a station, not necessarily the same one of departure. This behavior typically leads to a situation in which some stations become full and others are empty. Hence, a balanced system requires the redistribution of bicycles among stations.In this paper, we address the Bike sharing Rebalancing Problem (BRP), in which a fleet of capacitated vehicles is employed in order to re-distribute the bikes with the objective of minimizing total cost. This can be viewed as a special one-commodity pickup-and-delivery capacitated vehicle routing problem. We present four mixed integer linear programming formulations of this problem. It is worth noting that the proposed formulations include an exponential number of constraints, hence, tailor-made branch-and-cut algorithms are developed in order to solve them.The mathematical formulations of the BRP were first computationally tested using data obtained for the city of Reggio Emilia, Italy. Our computational study was then extended to include bike sharing systems from other parts of the world. The information derived from the study was used to build a set of benchmark instances for the BRP which we made publicly available on the web. Extensive experimentation of the branch-and-cut algorithms presented in this paper was carried out and an interesting computational comparison of the proposed mathematical formulations is reported. Finally, several insights on the computational difficulty of the problem are highlighted.