基于 BP 神经网络的结构损伤识别研究

针对结构的损伤识别进行了研究，选取结构固有频率平方变化比作为特征参数，建立12×25×1 BP网络结构，采用均方误差函数目标误差函数，学习函数选取梯度下降动量学习函数和L-M优化算法，对四层钢框架结构的损伤进行了检测。     

基于神经网络的企业信息能力模糊评价研究--以安徽省制造型企业为例

文章构建了企业信息能力评价指标体系，确定了由初始级、系统级、优化级、战略级和持续改善级构成的企业信息能力评语等级论域。运用神经网络确定模糊综合评价中的权重值，克服了现有其它方法主观性判断的不足。提出了信息能力模糊综合评价模型。利用该模型对安徽省制造型企业进行了实际应用分析。最后，对评价结果进行了分析并给出了政策建议。     

高职营养配餐课程网络教学平台的构建研究——以浙江商业职业技术学院旅游烹饪学院为例

随着信息技术的发展,网络教学作为一种新型的辅助教学手段是当前教学改革的研究热点,也是教育信息化、校园数字化建设的必然趋势。文章在分析营养配餐类课程开设背景的基础上,介绍了营养配餐网络教学平台的构建理念、构成及实践应用。实践证明,网络教学平台辅助课堂教学能更有效地提高教学质量。     

Tradespace exploration of in-space communications network architectures

Making architectural decisions in long lifecycle systems is challenging because the time between system definition and end of operations can span multiple decades, resulting in shifts in stakeholder needs and major advances in technologies. Space-based communications using relay satellite constellations is one such example, requiring substantial up-front planning to define capabilities and size capacity due to the large investment of time and resources. Additionally, there are numerous viable system architectures. In this paper, we build on existing methods to develop a graph-based decision method to assess and explore architectural flexibility in the future evolution of long lifecycle systems. The tradespace graph defines edges between similar architectures, quantifies the switching cost between architectures, using graphs to analyse the potential system evolution pathways. In a test case on NASA communication satellites, we find that hosting government communications payloads, in particular optical payloads, on commercial satellites could reduce cost and increase flexibility of the NASA network.     

华为负值PBGT切换技术应用

负值PBGT切换技术的实现和分层分级算法相似,但比分层分级算法更加灵活,它是移动通信系统中非常重要的技术。现通过工程实践多次使用网络优化工具设置负值PBGT切换参数,实现在双频网优化上的应用,可以避免乒乓切换引起掉话,该技术的应用有重要的现实意义。     

Design and planning for green global supply chains under periodic review replenishment policies

We quantify the impact of jointly optimizing strategic network design and tactical inventory planning on the cost and CO₂ emissions of multi-echelon logistics networks. The obtained insights indicate that longer optimized replenishment cycles reduce a node’s transportation cost and CO₂ emissions but increase its inventory costs. Moreover, under a fixed replenishment cycle, a node’s service level increases when supplied by a satellite warehouse. Finally: (i) the costs of implementing optimal green network design decisions could be misleading if inventory planning is neglected, (ii) greening of supply chains could become expensive, (iii) current legislative CO₂ ton prices hardly influence logistics networks.     

模糊层次分析法优化BP神经网络的交通冲突预测模型

本文通过全面剖析影响交通冲突的原因,以交通流量、道路几何设计和道路环境三方面的因素建立指标层次结构体系。提出基于模糊层次分析(FAHP)法优化BP神经网络(BPNN)的预测模型,应用于交通冲突预测。     

Operational performance of U.S. public rail transit and implications for public policy

In today's tough economic environment, governments at all levels face significant budget shortfalls and public rail transit systems must compete with other public services for government subsidies. It is critical that public rail transit systems be concerned with their operational performance and efficient use of resources. In this paper, we develop a methodology that measures a rail transit system's performance relative to that of other rail transit systems, compares its performance to an appropriate efficient benchmark system, and identifies the sources of its inefficiency. We analyze the relationship between public subsidies and operational performance of public rail systems and show an inverse relationship between subsidization and efficiency.     

How do stakeholder interactions influence national food security policy in the Caribbean? The case of Saint Lucia

Increasingly, multi-stakeholder processes have been recognized as being necessary to the development of public policies seeking to promote systemic innovation in response to complex and multidimensional challenges, such as household food security, rural development, and environmental change. Saint Lucia, a small island developing state located in the Caribbean, has been grappling with a wide range of agriculture, food and nutrition security challenges with varying degrees of policy success. Recognizing the significance of the challenge, this paper explores the nature of the stakeholder interactions surrounding the development of Saint Lucia’s 2009–2015 National Agricultural Policy and considers some of the implications for food and agriculture-related policy outcomes. Results reveal a general lack of supportive conditions for effective multi-stakeholder processes, including low stakeholder participation levels, conflicting roles of different forms of social capital in the interactions between stakeholders, and missing “boundary” organizations capable of facilitating a transition towards more flexible and adaptive institutions, enhanced knowledge exchange and learning, and greater trust among stakeholders in the policy network. Future avenues for research and development are subsequently identified.     

Predation and network based price discrimination in Chile

This paper uses a model of strategic interaction among firms –that set discriminatory and nonlinear prices– in addition to public information on prices of the plans marketed by the three major mobile phone companies, to assess the extent to which on-net/off-net price differentials in the plans they offered could represent predatory practices in the mobile telephony market in Chile. The results show that the largest companies offered a few plans with an off-net/on-net price differential larger than what a competitive theoretical model predicts. This larger differential is consistent with the notion of predation defined by Hoernig (2007) as reducing a competitor's profits. Despite the fact that these plans were a small fraction of all the plans mobile phone firms offered, they were recently banned by the antitrust authority because of their potential anticompetitive effects.