Electrical impedance tomography (EIT) is a recently developed medical imaging method which has practical advantages for imaging brain function as it is inexpensive, rapid and portable. Its principal use in validated human studies to date has been to image changes in impedance at a single excitation frequency over time, but there are potential applications where it is desirable to obtain images ...

Mines with exceptionally low-strength roof (UCS <3,500 psi and CMRR <40) are much more likely to struggle with roof falls than other mines. Weak roof is a particular problem for many room and pillar mines in the Midwestern and Northern Appalachian coal basins. Traditional roof support techniques are often not up to the challenge at these operations. This paper focuses on two mines, one operatin...

Abstract: In the paper, the folded-cascode low-noise operational amplifier (LNA) with constant-gm is proposed and analyzed. The channel-length split technique adopted to expand ratio of W/L of the differential pair transistor to improve the performance of LNA for the gain bandwidth product, noise and offset voltage. The channel-length split method is separated differential input transistor into...

We present an alternative post-processing on a CMOS chip to release a planar microelectrode array (pMEA) integrated with its signal readout circuit, which can be used for monitoring the neuronal activity of vestibular ganglion neurons in newborn Wistar strain rats. This chip is fabricated through a 0.6 μm CMOS standard process and it has 12 pMEA through a 4 × 3 electrodes matrix. The alternativ...

A real-time telemetry system, which consists of readout circuits, an analog-to-digital converter (ADC), a microcontroller unit (MCU), a graphical user interface (GUI), and a radio frequency (RF) transceiver, is proposed for amperometric and potentiometric electrochemical sensors. By integrating the proposed system with the electrochemical sensors, analyte detection can be conveniently performed...

There are two major design problems for upper seam longwall gateroads operating in a multi-seam environment. The first is to determine the location, magnitude and duration of stress transferred from lower seam mines; and the second is to predict the effect of stress transferred from lower seam mines on opening stability. To solve these problems for both longwall and room-and-pillar mines, case ...

F. Wiesinger, P-F. Van de Moortele, G. Adriany, N. De Zanche, C. Snyder, T. Vaughan, K. Ugurbil, K. P. Pruessmann Institute for Biomedical Engineering, ETH and University Zurich, Zurich, Switzerland, Center for MR Research (CMRR), University of Minnesota, Minneapolis, Minnesota, United States INTRODUCTION: Ultra-high field strengths and parallel imaging are expected to form a considerable syner...

A large number of health and wellness applications wish to monitor electrocardiogram signal (ECG) in the least intrusive way possible. The use dry textile electrodes with high input impedance bio-amplifiers is a common technique. This paper presents novel ultra-high buffer obtain reduced capacitance enhance acquisition results for or non-contact capacitive ECG electrodes. Based on different boo...

Many commercial benchtop impedance analyzers are incapable of acquiring accurate tetrapolar measurements, when large electrode contact impedances present, as in bioimpedance measurements using electrodes with micrometer-sized features. External front-end amplifiers can help overcome this issue and provide high common-mode rejection ratio (CMRR) input impedance. Several discrete component-based ...

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