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.     

Platform selection by software developers: Theory and evidence

This paper analyzes platform selection (affiliation) by game developers in the Japanese home video game industry. We develop an elementary model of affiliation by software developers and propose the hypothesis that wider availability of game titles for a platform positively inclines game developers to affiliate with that platform when releasing new game titles. Then, using data for Japan, we estimate a multinomial logit model that includes both the attributes of game developers and the characteristics of platforms, and find evidence supporting this hypothesis. Overall, the findings suggest that game developers expect the indirect network effect to apply, and the prospect of future growth matters to them when deciding with which platform to affiliate.     

一种通用数字中频正交扩频调制器的实现

提出了一种适应于宽带扩频通信系统的数字中频调制的实现方案,它基于正交调制、DDS、数字上变频和数字内插等技术,采用通用硬件平台,可以生成多种中频调制信号,可广泛用于数字化扩频通信电台、宽带CDMA、软件无线电、遥控遥测等通信系统中。     

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.     

财务软件操作中常见问题解析——以金蝶KIS标准版为例

结合教学实践，分析金蝶KIS标准版财务软件的主要功能模块——系统维护及系统初始化设置模块、账务处理模块以及工资管理、固定资产管理、出纳管理等存在的常见操作问题，便于广大初学者熟练掌握会计软件。     

Do R&D and ICT affect total factor productivity growth differently?

We analyze the effect of ICT and R&D on total factor productivity (TFP) growth across different industries in Sweden. R&D alone is significantly associated with contemporaneous TFP growth, thus exhibiting indirect effects. Although there is no significant short-run association between ICT and TFP, we find a positive association with a lag of seven to eight years. Thus, R&D affect TFP much faster than ICT-investments. We also divide ICT capital into hardware and software capital. To our knowledge, this distinction has not been made in any previous study analyzing TFP at the industry level. The results show that lagged hardware capital services growth is significantly associated with TFP growth. Hence, investments complementary to hardware are needed to reap the long-run TFP effects from reorganizing production.     

基于目的分支的软件配置管理模型

从软件配置管理应用中版本控制常面临的问题出发,与传统软件配置管理分支模型比较,说明基于目的分支的软件配置管理模型能更好地支持并行软件开发和软件发布控制。     

Q-analytics: An ethics case on unlicensed software usage

This short role-taking ethics case is designed to provide students with several different perspectives related to the unauthorized/unlicensed use of software within a realistic accounting setting. Although the case could be considered for use in a variety of accounting classes at both undergraduate and graduate levelswith limited preparation, it is likely to be most relevant to Accounting Information Systems, Auditing, Controllership, and Accounting Ethics courses. The case can be read in about ten minutes, after which the class is assigned to groups that deliberate over the concerns of six different roles regarding the software-usage issues implied in the case.The issues are relevant to the students because they will inevitably encounter software-usage problems in their personal or professional lives. Furthermore, they inevitably have been exposed to similar copyright-infringement issues in the realms of music and video, which helps make for a rich class discussion.The case has consistently generated considerable discussion and debate within a graduate-level controllership course. A survey of students from five graduate accounting classes over a three-year period indicates favorable perceptions of the case.     

数字化可编程直接序列扩频(DP-DS/SS)系统的设计

本文介绍了一种数字化可编程直接序列扩频(DP-DS/SS)系统的设计方案,借鉴了软件无线电的思想,基于FPGA DSP的结构实现数字化可编程功能,采用动态配置技术实现多模式工作。一些关键技术的研究使系统具有较强的适应性,部分应用结果表明该系统可以很好地应用于移动卫星通信和直扩抗干扰通信。     

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。