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41.
This paper investigates whether the existing Denominations of Origin (DOs) provide useful quality signals for wine consumers. To test our conjecture that the large number of existing DOs is too many for the typical consumer, we investigate the patterns of co-movement among average monthly wholesale prices for red wines from the 11 main DOs in Bordeaux over 16 years, 1999–2014. Our results indicate that consumers substitute among these wines according to the similarity of semantic elements in the names of DOs on the labels, and not according to prices or terroir that could reflect intrinsic quality where the names as such cannot. This finding suggests that the current DOs are too numerous and complex to provide helpful quality signals to consumers. A substantial reduction of the number of DOs might be warranted to better address the broader informational issue in wine markets.  相似文献   
42.
This study examined how music frequency affected consumers’ perception and decision making. The results of three experimental studies show that music frequency affects perceived distance between the sound source and the perceiver. Consequently, the representation of marketing message that matched (vs. mismatched) the background music's frequency enhanced consumers’ evaluative judgments. Specifically, Study 1A demonstrates that low‐frequency (vs. high‐frequency) music increased perceived distance. Studies 2, 3A, and 3B indicate that low‐frequency (high‐frequency) music matched products with abstract (concrete) representations and marketing messages signifying far (near) psychological distance. The congruency between psychological distance induced by music frequency and mental representations of products and message orientation offers a novel perspective on the notion of congruency. Moreover, Study 2 provides evidence that supports the congruency–fluency–evaluation chain (i.e., the mediating role of fluency), and Studies 3A and 3B show that the congruency has downstream effects. This study provides a theoretical contribution to the literature on the effects of music in marketing contexts by presenting convergent evidence that individuals exposed to low‐frequency (high‐frequency) music are inclined to construe a marketing message at a high (low) level.  相似文献   
43.
徐敏 《价值工程》2014,(23):78-79
张力控制在变频造纸设备中的应用是造纸业的控制难题。本文构建了变频造纸设备张力控制系统模型,通过张力检测装置采集张力值,经PLC接收和判定,最终组成了直接张力控制系统,有效地保证了张力的恒定。同时采用Simulink工具箱,模拟和分析了Matlab软件环境下张力控制系统的仿真运行,最终证实了张力控制系统在变频造纸设备应用中的可行性,为张力控制系统的后续研究与发展指明了方向。  相似文献   
44.
张阳 《价值工程》2014,(9):15-16
本文介绍了煤矿长斜巷正头掘进与斜巷中段联巷掘进同时施工的新型运输方式。  相似文献   
45.
李倩 《价值工程》2014,(31):224-225
局域互联网络(LIN)是一类串行数据通信的网络通信线,LIN的应用大大减少了车辆电气线路的使用数量,降低了电气线路的故障发生率。本文主要从传输方式、信号特性方面介绍LIN总线特性及LIN总线诊断特性。  相似文献   
46.
This study aims to investigate the hotel selection differences among different types of travellers through online hotel reviews. Specifically, the study performs a detailed examination of the differences in hotel key factors, criterion importance and selection results among five types of travellers, namely, business, couples, families, friends and solo. Using a sample of 194,885 online reviews on TripAdvisor.com, this study identifies the hotel key factors and criterion importance by employing the term frequency-inverse document frequency algorithm and Word2Vec algorithm. Additionally, a bounded rationality behavioural decision support model with picture fuzzy information is proposed to address hotel selection problems for different traveller types. Our results suggest that different types of travellers present differences in hotel key factors, criterion importance and selection results. However, families and friends have similar hotel selection results. This study can serve as a reference for hotel managers in understanding traveller preferences and for tourism website optimisation.  相似文献   
47.
重叠滤波多音(O-FMT)是针对滤波多音(FMT)系统频谱利用率低的缺点而根据超奈奎斯特(FTN)概念引入子载波重叠得到的方案。鉴于O-FMT系统在频偏环境下的性能缺陷,理论分析了频偏对系统信号各部分的影响,比较了O-FMT与正交频分复用(OFDM)系统的抗频偏性能。针对频偏性能优化问题,提出了基于最佳线性无偏估计(BLUE)的改进盲估计算法,设计了基于频域滤波器系数的内嵌结构进行频偏补偿。仿真实验表明,O-FMT相比OFDM具有更好的抗频偏能力,改进的盲估计算法估计值精度更高,抗干扰、抗衰落能力更强,设计的频偏补偿结构可以使系统获得更好的性能。  相似文献   
48.
将K-means聚类算法应用到无线局域网(WLAN)位置指纹定位中,虽然可以缩短定位时间,但是容易降低定位精度。为了解决此问题,提出了基于改进指纹聚类的WLAN定位优化方法。首先根据接收信号强度标准差来优化初始聚类中心的选取,然后对指纹数据进行聚类处理,最后进行在线定位。实验结果表明,与传统的WLAN位置指纹定位方法和K-means聚类定位方法相比,基于改进指纹聚类的定位优化方法不仅缩短了定位时间,还能有效提高定位精度。  相似文献   
49.
李宝智 《价值工程》2015,(19):120-122
结合青海百通公司的高炉情况,设计出了上料机改造方案。介绍了台达变频器在高炉卷扬调速系统中的应用情况,给出了电气原理图、注意事项和常见故障处理。实际应用的良好效果验证了该系统的稳定性和可靠性。  相似文献   
50.
Walking and participating in activities outdoors in old age can be restricted both by the physical capacity of the individual and by the maintenance and/or the design of the outdoor environment. The purpose of this paper is to compare frequency of walking and frequency of activity outside the home, reported environmental barriers and valuation of the outdoor environment between two areas, in one of which there was an intervention in the outdoor environment 5–8 years prior to this study. The paper is based on a questionnaire sent out in 2011, to all residents 65 years and older in two different areas, the Study Area, an area with an intervention, and the Reference Area. The results show that reports on functional limitations, use of mobility devices and walking difficulties were similar in both areas. Despite that, respondents in the Study Area had a significantly higher frequency of walking and they also participated to a higher degree in activities than respondents in the Reference Area, even though they reported more environmental barriers. The valuation of the outdoor environment was, however, similar in both areas. The results indicate that older people benefit from interventions in the outdoor environment. However, the results also emphasize the importance of good maintenance of the environment.  相似文献   
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