Cross‐Functional Influence and the Supplier Selection Decision in Competitive Environments: Who Makes the Call?

This paper presents the results of a multiple‐case study that examines how procurement and engineering personnel share priorities, have a common vision, and influence the supplier selection decision in competitive environments of varying risk and uncertainty. We interviewed 113 procurement and engineering respondents from 26 different companies/business units across up‐, mid‐, and downstream segments of the oil and gas industry. Following a middle‐range theorizing approach, we develop a series of working propositions and theoretical frameworks, utilizing goal congruence theory to sharpen proposition development and create suggested extensions for theory. In general, we find that engineering personnel tend to dominate cross‐functional decision making in higher risk environments and that more equal arrangements exist when both risk and uncertainty are low. When competitive environment risk is low but uncertainty is high, considerable disagreement arises over which function “leads” this decision. Higher risk environments drive higher goal congruence through shared vision and consensus on who makes supplier selection decisions.     

The implementation of an adjusted relative strength index model in foreign currency and energy markets of emerging and developed economies

This study proposes refinements to some weaknesses in the Relative Strength Index (RSI) model and tests its predictability over pre and post crisis periods for the most active USD based currency pairs, including two energy markets. A new model (AdRSI) is tested using daily data over 2001–2015. Benchmarked against RSI and buy-and-hold models, findings support an inverse relationship between energy and currency markets. While energy markets had relatively higher risk, Chinese yuan had the lowest annualized risk. AdRSI produced higher annualized returns, lower number of trades and higher annualized risk. Overall, the buy-and-hold model was superior with higher reward-to-volatility.     

测控通信系统资源重组的信号交换技术

测控通信系统的资源重组已在工程中逐步得到了认可与应用。要实现系统中各类资源的高效组合及有效利用，信号交换方式是直接影响资源重组规模与运行效能的关键环节。不同的交换方式直接关系到重组架构的形态，也决定了系统资源重组的范围、效率和能力。分析了不同信号交换形式的优劣，突出了基于IP协议的交换形式对于未来开放式资源重组系统的技术途径。所提出的设计思路可供测控通信系统实现全域资源重组借鉴及参考。     

Forecasting volatility with component conditional autoregressive range model

In this paper, we propose a component conditional autoregressive range (CCARR) model for forecasting volatility. The proposed CCARR model assumes that the price range comprises both a long-run (trend) component and a short-run (transitory) component, which has the capacity to capture the long memory property of volatility. The model is intuitive and convenient to implement by using the maximum likelihood estimation method. Empirical analysis using six stock market indices highlights the value of incorporating a second component into range (volatility) modelling and forecasting. In particular, we find that the proposed CCARR model fits the data better than the CARR model, and that it generates more accurate out-of-sample volatility forecasts and contains more information content about the true volatility than the popular GARCH, component GARCH and CARR models.     

核桃冷榨适宜温度的试验研究

采用单螺旋榨油机压榨的方式,对CH1500T型单螺旋榨油机进行了压榨核桃的试验,通过加热装置对榨膛辅助预热实现对核桃的预热处理,得到了不同预热时间(11 min、12 min、13 min、14 min、15 min)下核桃出油率.出油率、残油率、油脂酸价是3个常见指标(衡量榨油品质),因此经化学试验分别得到对应时间的饼粕残油率和油脂酸价,综合分析以上试验数据得到了核桃榨油的适宜预热时间.经红外测温仪测量得到该适宜预热时间下榨油机压榨后榨膛外壁36个拟定测点温度,依据热传导反问题理论,再通过Ansys Workbench热仿真得到榨膛内外壁温度分布情况.对比榨膛外表面实测温度与仿真温度,误差范围在-4.263％ ～8.155％,表明可以通过Ansys Work-bench热传导仿真来预测核桃冷榨适宜温度范围,从而得到核桃冷榨时榨膛内壁适宜温度范围为43.43～50.23℃.     

Determining profitable products in the retail market with consideration of cash limitation and exhibition periods

In the selection of profitable products, consumer preferences and retailer constraints in products supply must be considered. When data mining algorithms are used to discover the consumer's preferences from transaction database, the results may be biased, if the exhibition period of the products has not be considered. In this study a new method is proposed to adjust the support and confidence coefficients of traditional association rule mining algorithms such as Apriori or FP-growth taking into consideration of common exhibition periods. On the supply side, the retailer may have some limitations in terms of buying and supplying products in the store. In the most recent researches, only the shelf space constraint has been considered. In this study, financing as an important constraint in the retail market and the opportunity cost of money are imported in the selection of profitable products.The researcher's experiment on real world data shows that the number of frequent itemsets increases significantly when products exhibition periods are taken into consideration. In this case, if the retailer considers the opportunity cost of money as 1%, the profitable set composition will be changed by 10%. Also, when the opportunity cost is 1% and the retailer faces cash limitation, the number of products is reduced by 21% in the most profitable set, whereas the new set composition is 29.4% different from the base set.     

Estimators of long-memory: Fourier versus wavelets

Semi-parametric estimation methods of the long-memory exponent of a time series have been studied in several papers, some applied, others theoretical, some using Fourier methods, others using a wavelet-based technique. In this paper, we compare the Fourier and wavelet approaches to the local regression method and to the local Whittle method. We provide an overview of these methods, describe what has been done and indicate the available results and the conditions under which they hold. We discuss their relative strengths and weaknesses both from a practical and a theoretical perspective. We also include a simulation-based comparison. The software written to support this work is available on demand and we illustrate its use at the end of the paper.     

金融消费者界定的困境及解决思路

我国目前尚未存在对金融消费者明确的定义，一些学者认为金融消费者属于《消费者权益保护法》所规定的消费者范围，此种定义并不十分准确，《消费者权益保护法》中对消费者的界定存在着一些值得商榷的地方，将其笼统地运用于金融消费者的保护并不能起到较好的作用。金融消费者是购买、使用金融产品或接受金融服务的主体，在专门的投资机构进行投资行为时除外。     

Validation and forecasting accuracy in models of climate change

Forecasting researchers, with few exceptions, have ignored the current major forecasting controversy: global warming and the role of climate modelling in resolving this challenging topic. In this paper, we take a forecaster’s perspective in reviewing established principles for validating the atmospheric-ocean general circulation models (AOGCMs) used in most climate forecasting, and in particular by the Intergovernmental Panel on Climate Change (IPCC). Such models should reproduce the behaviours characterising key model outputs, such as global and regional temperature changes. We develop various time series models and compare them with forecasts based on one well-established AOGCM from the UK Hadley Centre. Time series models perform strongly, and structural deficiencies in the AOGCM forecasts are identified using encompassing tests. Regional forecasts from various GCMs had even more deficiencies. We conclude that combining standard time series methods with the structure of AOGCMs may result in a higher forecasting accuracy. The methodology described here has implications for improving AOGCMs and for the effectiveness of environmental control policies which are focussed on carbon dioxide emissions alone. Critically, the forecast accuracy in decadal prediction has important consequences for environmental planning, so its improvement through this multiple modelling approach should be a priority.