切削加工振动的分析和防治

切削加工振动主要有自激振动和受迫振动,它们分别与机床系统本身的特性、内部干扰力和外部干扰力有关.为了减振防振,必须准确判断振动的类型和产生的原因,综合分析引起振动的主要因素,找出它们的作用和相互关系,采取切实可行的有效措施隔断和减轻引起机床振动的各种干扰力,调整机床系统的固有频率、阻尼、刚度以提高其动态特性.     

Daily moods,health routines and recovery among employees working in the retail and services sector: A diary study

This study examined the quality and fluctuation of daily moods as well as health routines and means of recovery from work strain among employees (n = 38) working nonstandard, often unpredictable schedules in the retail and services sector in Finland. Data were collected via a background questionnaire and a one-week mobile diary. The results indicated that the daily moods of employees were relatively positive but varied greatly from day to day. Hectic working days, unpredictable changes in work schedules, and compounded responsibilities at home and work were reported as causes of daily strain stemming from work. In contrast, more sleep and exercise were positively associated with daily mood and, therefore, are likely to enhance recovery from work related strain. Additional activities employees reported as useful in recovering from work strain included low-effort leisure activities along with social activities with family and friends, as well as mastery experiences stemming from successful work experiences.     

Causal inference on networks under continuous treatment interference

This paper investigates the case of interference, when a unit’s treatment also affects other units’ outcome. When interference is at work, policy evaluation mostly relies on the use of randomized experiments under cluster interference and binary treatment. Instead, we consider a non-experimental setting under continuous treatment and network interference. In particular, we define spillover effects by specifying the exposure to network treatment as a weighted average of the treatment received by units connected through physical, social or economic interactions. Building on Forastiere et al. (2021), we provide a generalized propensity score-based estimator to estimate both direct and spillover effects of a continuous treatment. Our estimator also allows to consider asymmetric network connections characterized by heterogeneous intensities. To showcase this methodology, we investigate whether and how spillover effects shape the optimal level of policy interventions in agricultural markets. Our results show that, in this context, neglecting interference may underestimate the degree of policy effectiveness.     

信息传播过程中的噪声干扰及对策

在档案信息传播过程中所存在的干扰叫噪声干扰。根据产生原因的不同，将这种干扰分为物理噪声、语义噪声、应用噪声。消除噪声干扰可采取三条措施：选择优质的传播载体；加强知识储备；正确传播信息。