一种改进的CPFSK信号频率估计方法

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。     

基于OID编码体系的汽车电子标识编码应用研究

本文为了解决物联网所连接对象的多样性带来的标识体系存在不兼容、相互矛盾的问题，基于车联网RFID汽车电子标识的使用特点，创造性地提出将OID编码和汽车电子标识编码相结合的方案。首先简单介绍了基于发证机构及时间和基于汽车VIN码的两种OID编码规则；然后提出了OID编码在汽车电子标识芯片中的规划，主要是内存分配方案；最后介绍了相应区域的读写操作的具体方法。     

HR managers’ talent philosophies: prevalence and relationships with perceived talent management practices

Abstract

HR managers have different beliefs about the nature, value, and instrumentality of talent—referred to as ‘talent philosophies’. In line with cognitive psychology, we reason that talent philosophies are similar to mental models that influence how HR managers interpret and use talent management (TM) practices within their organizations. In this article, we explore the prevalence of four different talent philosophies (exclusive/stable; exclusive/developable; inclusive/stable; inclusive/developable) in a sample of 321?HR managers. We then explore how talent philosophies relate to organizational context (i.e. size, ownership form, multinational orientation) as well as to HR managers’ perceptions of their organization’s TM practices. Cluster analysis corroborated the presence of the four talent philosophies in our dataset. All four talent philosophies were represented almost equally often in the overall dataset. Organizational size was found to be related to talent philosophies, such that HR managers who worked in smaller organizations were more likely to hold an inclusive talent philosophy. We also found support for the relationship between talent philosophies and perceptions of the exclusiveness or inclusiveness of the organization’s definition of talent, and its degree of workforce differentiation. Contrary to expectations, results did not support a link between talent philosophies and perceived talent identification criteria.     

Measuring the effectiveness of US monetary policy during the COVID-19 recession

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.     

Reliable Inference in Categorical Regression Analysis for Non‐randomly Coarsened Observations

In most surveys, one is confronted with missing or, more generally, coarse data. Traditional methods dealing with these data require strong, untestable and often doubtful assumptions, for example, coarsening at random. But due to the resulting, potentially severe bias, there is a growing interest in approaches that only include tenable knowledge about the coarsening process, leading to imprecise but reliable results. In this spirit, we study regression analysis with a coarse categorical‐dependent variable and precisely observed categorical covariates. Our (profile) likelihood‐based approach can incorporate weak knowledge about the coarsening process and thus offers a synthesis of traditional methods and cautious strategies refraining from any coarsening assumptions. This also allows a discussion of the uncertainty about the coarsening process, besides sampling uncertainty and model uncertainty. Our procedure is illustrated with data of the panel study ‘Labour market and social security' conducted by the Institute for Employment Research, whose questionnaire design produces coarse data.     

张力控制系统在变频造纸设备中的应用研究

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。     

变频器内建PLC在上料机改造中的应用

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。     

When profession trumps potential: The moderating role of professional identification in employees’ reactions to talent management

Abstract

This study aimed to investigate the role that a professionalized context plays in shaping employee reactions to talent management decisions. We examined the mediating role of felt obligation in the relationship between talent ratings and organizational citizenship behavior. Further, the study tested whether professional identification moderates the relationship between talent ratings and felt obligation towards the organization. Five hundred and ninety-eight teachers that had recently received ratings of their talent status responded to a survey questionnaire. Felt obligation mediated the relationship between talent ratings and organizational citizenship behavior. Furthermore, professional identification moderated the relationship between ratings of potential and felt obligation in such a way that the relationship was strongest for the teachers expressing the lowest professional identification. At high levels of professional identification, the relationship was not significant. These results indicate that conventional talent management might be less effective for increasing favorable attitudes and behaviors among employees in highly professionalized contexts, such as the education sector.     

Identifying business opportunities for sustainable development: Longitudinal and experimental evidence contributing to the field of sustainable entrepreneurship

Which factors facilitate the identification of business opportunities for sustainable development? To answer this question, we develop a process model of sustainable opportunity identification. We argue that sustainable opportunity identification is a process with transitions from problem to solution identification and from solution to sustainable opportunity identification. Moreover, the transitions are facilitated by two factors—awareness of adverse consequences and entrepreneurial attitude—providing motivation and direction in the process. We tested our model in a field study (N = 107) and two experiments (N = 53 and N = 69). Our findings show that awareness of adverse consequences and entrepreneurial attitude influence the process of sustainable opportunity identification, explaining under which conditions people are more likely to identify business opportunities for sustainable development. Our study thus contributes to the field of sustainable entrepreneurship.     

The impact of reverse logistics process coordination on third party relationship quality: A moderated mediation model for multichannel retailers in the fashion industry

Multichannel retailing is a widely adopted strategy in the fashion industry. Companies in this industry find it a source of competitive advantage to invest in reverse logistics infrastructure. However, limited empirical studies investigate the enablers of the relationship quality between the retailers and their reverse logistics service providers. This study quantifies the impact of reverse logistics process coordination between retailers and logistics service providers on relationship quality. Moreover, it tests the mediating role of reverse logistics service quality and the moderating role of conflict frequency in this relationship. Data were collected through a survey using a purposive sample of 241 retail store managers from the fashion retail industry of Pakistan. For this purpose, a self-administered questionnaire was developed using a five-point Likert Scale to gauge the responses. Conditional process analysis was used to evaluate the moderated mediation model. The findings showed a significant positive impact of reverse logistics process coordination on the relationship quality with a logistics service provider, a significant positive mediation effect of reverse logistics service quality, and a significant moderation effect of conflict frequency on the indirect relationship. However, conflict frequency, contrary to the hypothesis in the study, strengthened the indirect relationship. Furthermore, the moderation effect of conflict frequency on the direct relationship was insignificant. This study will help managers better understand the best practices leading to effective management of reverse logistics processes, particularly product returns.