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21.
针对突发信号解调中多普勒频偏大的问题,提出了一种改进的连续相位移频键控信号(CPFSK)频率估计方法。首先接收信号平方运算使信号的调制指数加倍,再通过一次离散傅里叶变换(DFT),用搜索信号平方谱谱峰的方法实现突发信号频率估计。仿真实验表明,在低信噪比条件下,该算法的频率估计精度比经典的相位差频率估计算法提高了20%;该算法与广泛用于高动态突发信号的频率插值估计算法相比,同道干扰信道下信干比改善可达4 dB,DFT长度缩短约1/3。  相似文献   
22.
Influencers are ordinary individuals who have amassed large followings by demonstrating expertise in various niches on social media sites. We aim to propose (1) the visual presentation of an Influencer's extroversion as an antecedent to source credibility and purchase intentions and (2) personality matching in terms of extroversion between an Influencer and their audience as a moderator of such relationships. We chose the source credibility model and the similarity-attraction model as our theoretical frameworks. In our controlled online experiment (n = 165), the profile of a brand ambassador of a fashion brand was curated to create two levels of extroversion (i.e. low vs. high extroversion). Participants' self-reported extroversion levels were counterbalanced in these two conditions to create a personality match with the Influencer, entitled “extroversion congruence.” Our results suggest that the visual presentation of an Influencer's extroversion increases the perceived credibility of the Influencer and subsequent purchase intentions. Additionally, our findings show that these relationships were asymmetrically moderated by extroversion congruence: the positive effects of extroversion increase in the case of high extroversion among both the Influencer and their audience but decrease in the case of low extroversion.  相似文献   
23.
In line with Kang and Herr's work (2006), this research questions the ELM's contention that celebrity credibility serves foremost as a peripheral element in a persuasive communication context. Nevertheless, in a different light to the Kang and Herr's ‘either-central-or-peripheral-role’ of a source characteristic, this research advances that celebrity credibility plays concomitantly central and peripheral roles in a persuasive message context depending on product involvement and brand-purchase motive. Particularly, this research uses the notions of ‘source internalization’ and ‘source identification’ (Kelman, 1961) to theorize that source credibility can have a concomitant dual role (peripheral and central) in a persuasion context. More precisely, this research investigates the interactive effects of source identification and internalization with product involvement as well as brand-purchase motives on consumers' attitudes and intentions. Source internalization is predicted to have persuasive effects in the contexts of high-involvement as well as informational products. Source identification is predicted to have persuasive effects in the context of low-involvement as well as transformational products. The findings of two experiments show that celebrity credibility acts through only a single route (i.e., only internalization has persuasive effects) uniformly across different product involvement levels and brand-purchase motive types. We interpret these results with the lens of the ‘match-up’ hypothesis (Kamins, 1990).  相似文献   
24.
The COVID-19 recession that started in March 2020 led to an unprecedented decline in economic activity across the globe. To fight this recession, policy makers in central banks engaged in expansionary monetary policy. This paper asks whether the measures adopted by the US Federal Reserve (Fed) have been effective in boosting real activity and calming financial markets. To measure these effects at high frequencies, we propose a novel mixed frequency vector autoregressive (MF-VAR) model. This model allows us to combine weekly and monthly information within a unified framework. Our model combines a set of macroeconomic aggregates such as industrial production, unemployment rates, and inflation with high-frequency information from financial markets such as stock prices, interest rate spreads, and weekly information on the Fed's balance sheet size. The latter set of high-frequency time series is used to dynamically interpolate the monthly time series to obtain weekly macroeconomic measures. We use this setup to simulate counterfactuals in absence of monetary stimulus. The results show that the monetary expansion caused higher output growth and stock market returns, more favorable long-term financing conditions and a depreciation of the US dollar compared with a no-policy benchmark scenario.  相似文献   
25.
This study identifies acceptable premium price levels that customers would be willing to pay for organic menu items at restaurants in the United States. Previous literature indicates that health-related and socio-demographic characteristics significantly influence consumers’ intentions to purchase organic food. To advance our understanding of how different consumers respond to changes in organic food prices, this study examines the moderating effects of the level of health consciousness (high versus low), gender (male versus female), and age (young versus old) on the relationship between premium price levels and purchasing intentions. In addition, this study further investigates acceptable premium price levels for different consumer segments at two types of restaurants (casual dining versus fine dining). The results of this study provide guidelines for menu design and strategies for restaurateurs to devise effective price premiums for organic menu options.  相似文献   
26.
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   
27.
Green and organic markets have grown rapidly in recent times, thanks to the increasing global popularity of having a healthier lifestyle. Rising consumer awareness of the risks of synthetic chemicals for humans as well as the environment have boosted the demand for organic personal care products (PCPs). To better understand the micro-mechanisms guiding the organic PCPs buying process, this study builds on the social proof theory by examining the drivers leading this process in two different national contexts. Partial least squares structural equation modelling was used to conduct a multigroup analysis on a sample of 473 consumers (n = 266 from Spain, n = 207 from Italy). Findings reveal the significant role of environmental value, product knowledge, convenience & quality, and information adoption. Furthermore, the study introduces and validates the new construct ‘social reassurance’ explaining the psychological mechanisms leading the organic PCPs buying process.  相似文献   
28.
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   
29.
Despite the rise of digital, direct mailing as a marketing communication tool remains relevant and widely applied in practice. Nevertheless, research into the effectiveness of direct mailing in the online environment is scant. Key questions that remain entail how direct mails affect different online and offline consumer activity metrics throughout the purchase funnel and how they interact with digital marketing communication tools. The current paper, therefore, investigates these two questions by conducting two studies. First, we focus on the effect of direct mailing on zip-code level upper, middle, and lower funnel performance metrics over time by analyzing quasi-experimental data from a large European insurance firm. The results reveal that direct mailing significantly influences consumer activity metrics in the online channel (i.e., online search and clicking behavior), in support of cross-channel effects of direct mailing. Moreover, direct mailing is shown to be effective throughout the purchase funnel, both directly and indirectly, with a positive net sales effect. Second, we study the joint effect of direct mailing and display advertising by analyzing field experiment data from the same insurance firm. The results show positive synergy between direct mailing and display advertising. Therefore, despite the rise of digital, direct mailing still serves as an effective marketing tool, both by itself and in combination with digital marketing.  相似文献   
30.
This study aims to investigate consumer perceptions and reactions in terms of specific discount patterns (fixed price, 40% discount, discount from 500 TL to 300 TL and 20% + 25% discount) in price promotion. According to the results, specific discount patterns in price promotion have a significant effect on perceived price attractiveness and purchase intention. When the specific discount patterns in price promotion and gender interaction were analyzed in terms of perceived price attractiveness, the scenario of the “discount from TL 500 to TL 300” significantly differentiated from both the control scenario (fixed price) and experimental scenarios for female. For males, no significant difference was found between the control and experimental scenarios. In terms of purchase intention, a significant difference was found between the fixed price scenario and the discount scenario from 500 TL to 300 TL and between the fixed price and 20% + 25% discount scenario. The theoretical managerial implications of the study were discussed, and future research suggestions were presented.  相似文献   
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