高速铁路车站到发线运用优化研究

高速铁路车站到发线运用计划根据列车运行计划、动车组交路计划编制各列车占用到发线的起止时间,以均衡、合理使用到发线和方便旅客上下车为原则,为每一列车安排合适的到发线。在分析高速铁路车站到发线运用特点和原则的基础上,建立高速铁路车站到发线运用的0-1规划模型,并利用遗传算法求解。通过算例分析,编制长沙南站的到发线运用方案,说明方法的具体应用。     

基于软件无线电的中频数字化直扩系统的设计与实现

本文根据直接序列扩频原理,给出了一种基于软件无线电思想的中频数字化直扩系统的设计方案,并采用可编程数字器件实现。实验结果表明该方法达到了设计要求,并具有良好的通用性和灵活性。     

一种改进的不完全指数复制方法

本文在考虑交易成本和投资组合动态调整的基础上,建立混合整数线性规划模型,引入内核搜索分析框架进行近似求解,并利用沪深300进行实证研究。研究发现,一是相比于基本内核搜索法,增强型内核搜索法仅在基准指数成分股数量很大时才会较大幅度提高求解质量;二是考虑投资组合动态调整的模型不仅更稳健,而且跟踪的继承性和保持性更好,尤其适用于单边市场;三是过度刻画现实交易特征一定程度上会降低不完全指数复制模型的复制和预测效果。     

Fast and accurate yearly time series forecasting with forecast combinations

It has long been known that combination forecasting strategies produce superior out-of-sample forecasting performances. In the M4 forecasting competition, a very simple forecast combination strategy achieved third place on yearly time series. An analysis of the ensemble model and its component models suggests that the competitive accuracy comes from avoiding poor forecasts, rather than from beating the best individual models. Moreover, the simple ensemble model can be fitted very quickly, can easily scale horizontally with additional CPU cores or a cluster of computers, and can be implemented by users very quickly and easily. This approach might be of particular interest to users who need accurate yearly forecasts without being able to spend significant time, resources, or expertise on tuning models. Users of the R statistical programming language can access this modeling approach using the “forecastHybrid” package.     

Symbolic regression for better specification

This note introduces the concept of symbolic regression (SR) to tourism and hospitality research. SR uses genetic programming to find the model that best fits the data without a need to pre-specify a functional form or to impose a certain model as a starting point. In other words, SR helps to uncover the intrinsic characteristics of the data at hand. Our view is that SR can serve as an improved method of testing for misspecification. In this note, we propose to derive the true functional form of the residual using SR. We then use this information to improve the forecasts of the linear regression model and, to perform hypothesis tests if needed.     

Implementing product platforms in the global enterprise: Lessons from an LED industry leader

Product platforming—using technology subsystems or components that are shared within and across product lines—is a proven way to increase the effectiveness of innovation processes in established companies and startups alike. Yet, embracing the product platforming strategy turns out to be difficult in practice, particularly within the context of global, diversified companies. In this article, we examine the strategies and challenges of implementing product platforms across multiple business segments and multiple geographies. Using the experience of global LED industry leader Signify, we explore the challenges of global platforming and the technological, organizational, management process transformations needed for success. We also examine how platforming strategies change as manufacturers enter the world of connected things.     

无限冲击响应数字滤波器设计软件

<正> 经营机制必须转换企业活不活,关键在于企业经营机制好不好。当前,我国许多企业经济效益滑坡,主要就是因为旧的企业经营机制管理层次过多,人浮于事现象严重,市场应变力不强等因素造成。相反,从当前实际情况看,我国一些非国营企业,包括乡镇企业、“三资”企业、私营企业,因为其本身不但是自主经营、自负盈亏,而且生产经营活动基本上是由市场调节,同市场和市场经济在客观上已经结合在一起,特别在治理整顿期间,他们不但经受住经济紧缩的考验,而且通过自觉优化结构,提高技术质量档次,反而发展得更好了。究其原因,就是因为他们的企业经营机制已经基本解决了。由此可见,转换企业经营机制已经势在必行,早转晚转都要转,早转早主动,晚转要被动,不转要受穷。     

基于软件无线电的WCDMA仿真平台

本文介绍了一种关于3G的仿真平台的研究、开发和验证。结合软件无线电思想，参照3GPP协议，在COSSAP软件包中搭建起一个具有通用结构的、基于第三代WCDMA、FDD方式的下行链路物理层的仿真平台，并进行了Turbo编译码、RAKE接收机等3G关键技术的研究和单路数据业务、单路话音业务及多业务复用时系统性能的仿真验证。仿真结果与相关文献拟合得较好，结果证明可以把它作为进一步研究软件无线电中关键技术的基础平台。     

一种基于DSP+FPGA的控制系统方案设计

介绍了一种基于DSP FPGA技术的控制系统的设计方案，给出了系统硬件和软件的设计以及关键技术的实现。该方案具有控制结构简单、可靠性高、扩展性好等特点，具有一定的通用性。     

FORTRAN语言及汇编语言在坐标测量中的混合编程技术

本文论述了Fortran在坐标测量数据采集系统以及图形输出系统中与汇编语言的程序连接及调用方法,讨论了利用Fortran语言进行测量样本点的拟合、画线以及图形输出问题,给出了编程方法及实例。