Some issues in blockchain for accounting and the supply chain,with an application of distributed databases to virtual organizations

This paper reviews some recent blockchain‐based applications for information capture, distribution and preservation. As part of that review, this paper examines two key concerns with current blockchain designs for accounting and supply chain transactions: data independence and multiple semantic models for the same information distribution problem. Blockchain applications typically integrate database, application and presentation tiers all in the same ledger. This results in a general inability to query information in the ledger and other concerns. Further, since most applications appear to be private blockchain applications, there is a concern of agents needing to accommodate multiple blockchains depending on who their trading partners are and what they request. Finally, this paper uses a distributed database to design a ‘blockchain‐like’ system for virtual organizations.     

Characterizations of negative multinomial distributions based on conditional distributions

In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied.     

分布式并行计算网格系统的设计与实现

基于网格计算技术提出了一种分布式的有限元并行计算网格系统的原型DPFEM的构建方法.探讨了DPFEM的系统设计目标,系统平台,软件配置以及系统运作机制.     

投入产出乘数模型与其扩展方法

在投入产出模型里引入凯恩斯乘数理论，建立能够计算结构化乘数的投入产出乘数模型，是近年来投入产出领域探讨较多的一个问题。从前提假设、乘数效应的传导机制和最终推导结果等方面对凯恩斯乘数模型和投入产出乘数模型进行比较，指出建立投入产出乘数模型将凯恩斯乘数进行结构化处理，应该从放宽前提假设条件入手，并以引入列向旁侧效应为例对原模型进行了扩展。     

物流信息系统对物流现代化影响的探讨

阐述了现代物流与传统物流的区别,分析服务和信息技术对现代物流的作用,研究提高物流信息系统性能的途径,提出了物流技术新概念。     

A saddlepoint approximation to the distribution of the sum of independent non‐identically uniform random variables

Calculating the probability of the corresponding significance point is important for finite sample sizes. However, it is difficult to evaluate this probability when the sample sizes are moderate to large. Under these circumstances, consideration of a more accurate approximation for the distribution function is extremely important. Herein, we performed a saddlepoint approximation in the upper tails for the distribution of the sum of independent non‐identically uniform random variables under finite sample sizes. Saddlepoint approximation results were compared with those for a normal approximation. Additionally, the order of errors of the saddlepoint approximation was derived. © 2014 The Authors. Statistica Neerlandica © 2014 VVS.     

Ad hoc网络中基于多波束天线的集中式低时延调度算法

UxDMA算法是一种高效的集中式算法，是用于时分多址、频分多址和码分多址信道分配的统一算法。在UxDMA的基础上，利用多波束天线的多波束形成能力，针对低时延定向ad hoc网络提出了一种集中式调度算法——CLSM(Centralized Low-delay Scheduling Algorithm Based on Multi-beam Antennas)。CLSM通过不同时延等级限制的报文来比较着色后发送链路的优先级，优先选择高优先级链路传输。通过仿真验证了CLSM的性能：与UxDMA相比，该算法在多时延限制的发送端调度中表现出了更好的吞吐量和时延性能。     

Broadband connected employees and labour productivity: a comparative analysis of 14 European countries based on distributed Microdata access

In this study, the association between information and communication technology (ICT) intensity in firms and labour productivity is explored across 14 European countries for the years 2001–2010. ICT intensity is approximated by the proportion of broadband internet-enabled employees, a novel indicator measuring not only adoption but also diffusion within and among firms. Data have been retrieved by means of the distributed microdata approach (DMD) from registers on business, trade and education as well as from surveys on production, ICT usage and innovation activities in firms held at the national statistical offices. This pioneering approach allows access to otherwise confidential linked firm-level information in dimensions not earlier available. Pooled OLS estimations based on approximately 400,000 observations in harmonised and representative datasets show that in a majority of countries there is a significant and positive relationship between the proportion of broadband internet-enabled employees and labour productivity in firms. However, the strength of the relationship varies across countries and industries. Manufacturing firms receive 50% larger estimates than the services firms, while the latter instead experience the positive association more frequently.     

Search reduction in hierarchical distributed problem solving

Knoblock and Korf have determined that abstraction can reduce search at a single agent from exponential to linear complexity (Knoblock 1991; Korf 1987). We extend their results by showing how concurrent problem solving among multiple agents using abstraction can further reduce search to logarithmic complexity. We empirically validate our formal analysis by showing that it correctly predicts performance for the Towers of Hanoi problem (which meets all of the assumptions of the analysis). Furthermore, a powerful form of abstraction for large multiagent systems is to group agents into teams, and teams of agents into larger teams, to form an organizational pyramid. We apply our analysis to such an organization of agents and demonstrate the results in a delivery task domain. Our predictions about abstraction's benefits can also be met in this more realistic domain, even though assumptions made in our analysis are violated. Our analytical results thus hold the promise for explaining in general terms many experimental observations made in specific distributed AI systems, and we demonstrate this ability with examples from prior research.This research has been sponsored, in part, by the National Science Foundation under grants IRI-9015423 and IRI-9010645, by the University of Michigan Rackham Graduate School, and by a Bell Northern Research Postgraduate Award.     

基于模拟退火算法的智能天线广播波束权值生成方法

文章采用模拟退火与随机搜索相结合的优化算法,给出了智能天线广播波束赋形中特定形状广播波束所对应的权值生成方法。依据智能天线系统扇区覆盖模式的要求,并结合智能天线的阵列结构,利用模拟退火与随机搜索相结合的优化算法可得到每个阵元所需设置的幅度和相位权值。该方法适用于特殊广播波束的情况,对智能天线技术的应用具有重要意义。