Origin 8软件在弹簧振子和惯性秤中的应用

采用Origin软件研究了惯性称和弹簧振子的振动周期T2和质量m的关系以及不同形状的弹簧修正系数C的关系。通过Origin软件拟合可以得到符合实验要求的光滑曲线,使得实验结果处理更加直观和简便。实验结果表明,弹簧的修正系数C和弹簧的形状有关,不具有普适性。     

OFDM系统干扰控制的联合预编码

为研究正交频分复用(OFDM)系统的带外（OOB）辐射和高峰值平均功率比（PAPR）两个问题，阐述了两个问题的成因和传统技术的优势与不足，介绍了常见的预编码矩阵。根据OFDM系统原理，对OOB辐射和PAPR问题进行建模，构建新的预编码系统模型。最后对传统OFDM、预编码、联合预编码三者进行了比较，并展望了预编码干扰控制需进一步研究的方向。     

大空间建筑防火分隔措施探析

大空间由于其面积超过消防规范对防火分区的要求，如采取常规的防火分隔措施，将破坏大空间的连续性．在消防设计时一直是个难题，文章通过相关的计算，通过对火焰辐射热的分析，在会展中心内设置合理宽度的防火隔离带．以达到进行防火分隔的目的。     

TESTING FOR PURCHASING POWER PARITY AND UNCOVERED INTEREST PARITY IN THE PRESENCE OF MONETARY AND EXCHANGE RATE REGIME SHIFTS

Testing for purchasing power parity (PPP) and uncovered interest parity (UIP) has been the focus of many empirically oriented studies. While these simple economic theories of exchange rate and interest rate determination are theoretically attractive, the empirical support for these equilibrium conditions is at best mixed. Many potential reasons have been cited in the literature for the failure of such studies, ranging from market imperfections to inappropriate modelling strategies. The current state‐of‐the‐art procedure involves testing for two cointegrating vectors in a multivariate error correction model which may be economically identified as the PPP and UIP relations. However, such a procedure does not account for policy regime shifts which distort the underlying PPP and UIP relations. In this paper, a Markov‐switching vector error correction model (VECM) is considered for time series data in which monetary and exchange rate regime shifts are known to be present. Weak evidence in favour of PPP and UIP is established in a standard linear VECM, although the residuals of this model indicate that it is inappropriate in terms of functional form. The Markov‐switching VECM, however, provides convincing evidence in favour of both the PPP and UIP relations and a marked improvement in the residual distributions.     

基于电力用户用电信息采集系统中显示的特殊负荷曲线的错误接线方式的判定和分析

本文通过对电力用户用电信息采集系统中的一起特殊的负荷曲线理论分析与装置实际接线检查结果的对照,最后判定其接线错误方式,并计算出更正率,为电量退补提供了合理的依据,保证电量退补能够公平、公正地进行。     

一种基于B样条拟合的颜色校正方法

多重投影仪在大尺度显示系统中的解决颜色校正问题一直是比较棘手的,通过颜色色度匹配技术或者用分光光计来对投影仪进行颜色校正可以达到比较好的效果,但是这两种技术是基于硬件系统来实现的,成本相对高昂。通过三次B样条拟合方法进行多重投影仪颜色校正,不仅可以降低成本,同样能够达到一个比较好的效果。     

焊接危害的防护设计

分析焊接操作对焊接工产生的三种主要危害,针对不同原因因素,基于中小企业的实际情况,提出不同的解决方法,逐个给出合理的防护设计,实现了操作成本低、实施方案简单的设计思路,对焊接职业病的防护提出具体建议。     

The Impact of Mobile App Adoption on Cross-buying: The Moderating Roles of Product Category Characteristics and Adoption Timing

With more and more companies introducing mobile apps and consumers using them during the purchase journey, it is increasingly important to understand the consequences of app adoption on behavioral outcomes. This paper investigates the impact of app adoption on the number of additional products purchased by customers (i.e., cross-buying) and how this effect varies across different product categories and different customers. We focus on two key product category characteristics (utilitarian vs. hedonic nature and perceived risk) and on adopters who vary in their adoption timings (early vs. late adopters). Using data from an online retailer and a combination of propensity score weighting with difference-in-differences and Heckman correction estimation techniques, the results show that app adoption has a positive effect on cross-buying overall, but the effect varies greatly across products and consumers. App adoption promotes additional product purchases for hedonic products but leads to less cross-buying for utilitarian products. In addition, early adopters purchase a higher number of additional product categories than late adopters, with this difference decreasing over time and for new consumers compared to existing customers. These results offer novel insights into the behavioral consequences of app adoption and provide managers with useful recommendations for improving the effectiveness of their mobile app investments.     

我国不同部门服务贸易对经济增长的影响

本文利用我国1982-2005年不同部门服务贸易的进口、出口和GDP数据,根据协整和向量误差修正模型理论,分析了三者之间的关系。结论表明:不同部门三者之间存在一个长期稳定的均衡关系,短期偏离向长期调整的速度较快,且出口是经济增长的Granger原因。     

人民币实际有效汇率变动对中部六省进口的影响

通过对中部六省1994—2012年的进口额和地区生产总值及人民币实际有效汇率年度数据进行时间序列的协整回归分析和面板数据的协整分析,得出如下结论:人民币汇率、进口额、地区生产总值间存在长期均衡关系,并且进口额与汇率负相关,与地区生产总值正相关。这与传统的"升值增加进口"不符。在结论的基础上,提出如下建议:调整企业内部结构和产业结构;优化进口结构;保持汇率稳定。