Shields

About: Shields is a research topic. Over the lifetime, 1456 publications have been published within this topic receiving 10896 citations.

Mechanised Shield Tunnelling

Abstract: This book is translated from German. The development potential of the mechanised shield tunnelling method is far greater than that of the shotcrete method and other traditional tunnelling machines because it is a safer, more effective method of tunnel construction. This book considers the planning of the construction method and design of the machine in harmony with the geological and hydrological conditions, settlement requirements and safety considerations. The technological developments in Germany and world-wide are presented. The book includes chapters on tunnel lining, tailskin seals, grouting and injection procedures, open-faced shields, compressed air shields, slurry shields, earth pressure balance shields, combined shields and special configuration shields and special construction methods.

Shielding Effectiveness of Braided-Wire Shields

Abstract: An analysis of the shielding effectiveness of braidedwire shields is made using the parameters of the woven wire and the theory of electromagnetic coupling through small irises. The coupling through the rhombic-shaped holes in the braid is approximated by using the electric and magnetic polarizabilities of elliptical holes of the same width and length as the rhombus. The analysis develops the transfer impedance and the mutual capacitance of the shield. The transfer impedance is calculated and plotted for shields of different optical coverages. The variation of mutual capacitance and mutual inductance with the weave angle of the braid are examined.

Shielded magnetic tunnel junction magnetoresistive read head

Abstract: A magnetic tunnel junction (MTJ) magnetoresistive read head for a magnetic recording system has the MTJ device located between two spaced-apart magnetic shields. The magnetic shields, which allow the head to detect individual magnetic transitions from the magnetic recording medium without interference from neighboring transitions, also function as electrical leads for connection of the head to sense circuitry. Electrically conductive spacer layers are located at the top and bottom of the MTJ device and connect the MTJ device to the shields. The thickness of the spacer layers is selected to optimize the spacing between the shields, which is a parameter that controls the linear resolution of the data that can be read from the magnetic recording medium. To reduce the likelihood of electrical shorting between the shields if the shield-to-shield spacing is too small, each of the shields can have a pedestal region with the MTJ device located between the two pedestals, so that the shield-to-shield spacing outside the pedestal regions is greater than in the pedestal regions.

Self-Cleaning Transparent Dust Shields for Protecting Solar Panels and Other Devices

Abstract: The development of transparent flexible dust shields using both single- and three-phase electrodynamic shields is reported here for possible application on Mars and Earth to minimize obscuration of solar panels from the deposition of dust. The electrodynamic screens (EDS) are made of transparent plastic sheets, such as polyethylene terephthalate (PET) for its UV radiation resistance, and a set of parallel conducting electrodes made of transparent indium tin oxide (ITO) embedded under a thin transparent film. The basic principle of EDS operation, a simplified mathematical model of particle trajectories, the experimental setup used for testing the screens, and their dust removal efficiencies (DRE) are described. Results of our measurements on dust removal efficiency of EDS as a function of the particle size and electrostatic charge distributions of Mars simulant dust are reported. The results show that the EDS technology has a strong potential for protecting solar panels against dust hazards with DRE higher...