This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the...This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the advantages in slide-film damping and large vibration amplitude, such a device makes atmospheric packaging a low-cost option for practical manufacture. In this letter, we present the operating principles and specifications, the design structure, as well as the finite element simulation. Computational analysis shows that our design obtains good results in device parameters setting, while its simplicity and low-cost features make it an attractive solution for applications.展开更多
This paper examines whether customer base composition in the US,that is,whether a firm's major customers are government entities or publicly traded companies,affects the properties of its management earnings forec...This paper examines whether customer base composition in the US,that is,whether a firm's major customers are government entities or publicly traded companies,affects the properties of its management earnings forecasts(MEFs).Using a sample of 1,168 MEFs from 1998 to 2014,we find that firms whose major customers are government entities(i.e.,govemment suppliers)issue more precise and more accurate MEFs than firms whose major customers are public companies(i.e.,corporate suppliers).Moreover,when managers disclose negative information to the market,earnings forecasts issued by government suppliers have greater price impact than those issued by corporate suppliers.Collectively,our empirical results suggest that having major govemment customers has a positive impact on the quality of MEFs.展开更多
基金Supported by the National Natural Science Foundation of China (No.60172001).
文摘This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the advantages in slide-film damping and large vibration amplitude, such a device makes atmospheric packaging a low-cost option for practical manufacture. In this letter, we present the operating principles and specifications, the design structure, as well as the finite element simulation. Computational analysis shows that our design obtains good results in device parameters setting, while its simplicity and low-cost features make it an attractive solution for applications.
基金the financial support for the research project No.15507217 by the General Research Fund from the Research Grants Council of the Hong Kong Special Administrative Region Government.
文摘This paper examines whether customer base composition in the US,that is,whether a firm's major customers are government entities or publicly traded companies,affects the properties of its management earnings forecasts(MEFs).Using a sample of 1,168 MEFs from 1998 to 2014,we find that firms whose major customers are government entities(i.e.,govemment suppliers)issue more precise and more accurate MEFs than firms whose major customers are public companies(i.e.,corporate suppliers).Moreover,when managers disclose negative information to the market,earnings forecasts issued by government suppliers have greater price impact than those issued by corporate suppliers.Collectively,our empirical results suggest that having major govemment customers has a positive impact on the quality of MEFs.
