Improved micro-contact resistance model that considers material deformation, electron transport and thin film characteristics

This paper reports on an improved analytic model forpredicting micro-contact resistance needed for designing microelectro-mechanical systems (MEMS) switches. The originalmodel had two primary considerations: 1) contact materialdeformation (i.e. elastic, plastic, or elastic-plastic) and 2) effectivecontact area radius. The model also assumed that individual aspotswere close together and that their interactions weredependent on each other which led to using the single effective aspotcontact area model. This single effective area model wasused to determine specific electron transport regions (i.e. ballistic,quasi-ballistic, or diffusive) by comparing the effective radius andthe mean free path of an electron. Using this model required thatmicro-switch contact materials be deposited, during devicefabrication, with processes ensuring low surface roughness values(i.e. sputtered films). Sputtered thin film electric contacts,however, do not behave like bulk materials and the effects of thinfilm contacts and spreading resistance must be considered. Theimproved micro-contact resistance model accounts for the twoprimary considerations above, as well as, using thin film,sputtered, electric contact

Design of a low-cost high speed data capture card for the Hubble Sphere Hydrogen Survey

Includes bibliographical references (leaves 101-105).This thesis describes the design and implementation of a low-cost high speed data capture card for the Hubble Sphere Hydrogen Survey (HSHS). The Hubble Space Hydrogen Survey was initiated in an effort to build a low-cost cylindrical radio telescope for an all sky redshift survey with the observational goal to produce a 3-dimensional mapping of the bulk Hubble Sphere using Hydrogen 21cm emissions. This dissertation ï¬ rst investigates the system design to see how each of the user speciï¬ cations set by the planning team could be achieved in terms of design decisions, component selection and schematic capture. The final design. AstroGIG, satisï¬ es the user speciï¬ cations by capturing data up to a full power bandwidth of 1.7GHz with an instantaneous bandwidth of ≤ 250MHz white maximizing the dynamic range. AstroGIG buffers, processes, stores and ï¬ nally transmits the data through a 4-lane PCI-Express interface to a standard PC where the majority of the processing is performed. The system implementation is then described where issues relating to the process of transforming schematics into a physical PCB, and HSHS integration are discussed. The design is veriï¬ ed through Hyperlynx simulations to give a high degree of certainty that physical implementation and production would be successful. Results from tests on the actual hardware characterizing the overall system performance are presented. Conclusions are drawn based on these results and suggestions for future work and design improvements are recommended

High dynamic range optical devices and applications.

Much of what we know about fundamental physical law and the universe derives from observations and measurements using optical methods. The passive use of the electromagnetic spectrum can be the best way of studying physical phenomenon in general with minimal disturbance of the system in the process. While for many applications ambient visible light is sufficient, light outside of the visible range may convey more information. The signals of interest are also often a small fraction of the background, and their changes occur on time scales so quickly that they are visually imperceptible. This thesis reports techniques and technologies developed for sensing and detecting rapid transient phenomenon using ambient light in the infrared (IR) spectrum. Currently, high dynamic range optical sensor technology leveraging low-noise and real-time signal processing is employed for applications to human, animal and structural health monitoring, Earth surface motion and environmental monitoring, material defect analysis and astronomy. This work describes the development and fabrication of devices that are made using a novel 32-bit data acquisition system (DAQ), as well as custom-designed circuits for integrating current optical sensing devices into systems for such applications. This thesis also describes the design, construction, and application of an impulse generator for materials testing and a custom-designed Ethernet-connected automated optical fiber positioning stage with examples of their applications to passive non-contact optical sensing

Examination of marine sediments with a sub-bottom profiling system

Imperial Users onl

Space programs summary no. 37-29, volume 111 for the period july 1, 1964 to august 31, 1964. deep space network

Deep space network - engineering and development progress in tracking station, space flight operations, communications, and advanced antenna system

Flight prototype electrostatic ballastic pendulum Final report

Flight prototype electrostatic ballistic pendulum momentum transduce

Manufacturing checkout of orbital operational stages Midterm report, period ending 24 Feb. 1965

Manufacturing checkout of orbital operational Saturn S-IVB stage and instrument unit for parking orbit operation

Mariner IV Mission to Mars. Part I

This technical report is a series of individual papers documenting the Mariner-Mars project from its beginning in 1962 following the successful Mariner-Venus mission. Part I is pre-encounter data. It includes papers on the design, development, and testing of Mariner IV, as well as papers detailing methods of maintaining communication with and obtaining data from the spacecraft during flight, and expected results during encounter with Mars. Part 11, post-encounter data, to be published later, will consist of documentation of the events taking place during Mariner IV's encounter with Mars and thereafter. The Mariner-Mars mission, the culmination of an era of spacecraft development, has contributed much new technology to be used in future projects

Phase 1 of the First Solar Small Power System Experiment (experimental System No. 1). Volume 2: Appendix A - D

Recommended conceptual designs for the baseline solar concentrator and electrical subsystems are defined, and trade offs that were evaluated to arrive at the baseline systems are presented. In addition, the developmental history of the Stirling engine is reviewed, the U4 configuration is described, and a Stirling engine heat pipe system is evaluated for solar application where sodium vapor is used as the heat source. An organic Rankine cycle engine is also evaluated for solar small power system application