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The thesis is composed of two topics : a low-noise instru-mentation amplifier (IA) for neural signal sensing and a low-power implantable bladder pressure monitor SOC (system-on-chip). A low-noise instrumentation amplifier for bio-medical appli-cations is proposed in the first topic. It is designed for sampling vague neural signals thanks to its high gain, high CMRR in a pre-defined bandwidth. A low-power implantable bladder pressure monitor system is presented in the next topic. The system contains several parts : a commercial pressure sensor, an IA, an analog to digital converter (ADC), a parallel to serial converter (PtoS), an RF transmitter and a sleep controller. The IA with 1-atm canceling is designed for high resolution and linearity in the pre-defined bladder pressure range. For low power and low speed applications, a successive approximation ADC (SA ADC) is employed in the system. A clear flag is added to the PtoS to enhance reliability. Our chip saves a great portion of power to extend the processing time owing to the novel sleep controller.

Humpback whales (Megaptera novaeangliae) belong baleen whales. They migrate between high-latitude summer feeding regions and low-latitude wintering regions where calving and make place.There were 1~60 humpback whales whaled every year during 1920~1967 in southern Taiwan. However, only a few sights were recorded in the past twenty years. A male humpback whale was sighted on the east coast of Taiwan in March, 2000. His songs recorded during between three-day tailing were analysed. There were five themes and nine units in the songs, a complete song duration lasted about 14.2 minutes. The maximal sound pressure level was 189.6 dB (n=32, SEM =2.81). The acoustic characters (i.e., signal duration, time between two signals, theme duration, fundamental frequency) of the songs were not significant different. A visual comparison of the spectrograms of the sound units from this particalar whale with those northwest Pacific Ocean showed similarity. This individual was a member of the population in the northwest Pacific Ocean. This conclusion was also supported by the result of Photo-ID of its fluke. Ceatceans live in the water and develop the special model to produce sounds. There are two kinds of communicative signals: pulses and whistles. These two signals were characters of phylogenetic relationship and the outgroup was red deer. There were two monophyletic groups. Evolution of communicative signals in cetaceans was whistle existent and added the pulses signals. Last, the whistles lost and only with pulses. The fumctions of pulse signals in communication was unknown in delphinidae. Sperm whales, pygmy sperm whales, dwarf sperm whales, Baird¡¦s beaked whales and Hector¡¦s dolphins were only use pulse signals. The reason of this change was unclear.

Isolation of terrestrially-observed magnetic signals by restoring their diffusive loss due to subsurface electrical conductivity sufficiently correlates these signals with those derived from the Alfven ionospheric electron movement of refraction variation. Temporary magnetic observatories were established on a conductive sedimentary basin (with a sampling interval of 5 s) and on a resistive large igneous intrusion (with a sampling interval of 10 s). Conventional modeling techniques estimate and remove the effects of the magnetometer, geomagnetic diurnal changes, whorls (solar quiet current vortices), and some bays from the acquired signals. Conventional one-dimensional skin depth modeling estimates the diffusive attenuation. The residual magnetic signal and the diffusive filter (as applied to the topography) become quantities in the linear system estimation of the geoelectric subsurface. Angular frequency domain least squares solution of the equations yields an isolated magnetic anomaly spectrum. Interpretive refinement, by selection of the zero or near zero curvature onset of either the spectrum's real or imaginary component, critically prepares the signal solution for correlation to a pseudomagnetic anomaly signal. This is an independently-derived sequence of anomalous values derived from Global Positioning System (GPS) refracted ranges. Detailed application of the Biot-Savart law provides independent anomaly signals to which the magnetic anomalies correlations show great correlation improvement by the isolation. These correlation improvements are from 2% to 83% and 9% to 91% for the sedimentary basin and from 2% to 96% and 24% to 78% for the igneous intrusion.

Predator mimicry refers to a peculiar and rarely investigated example of Batesian mimicry in nature. This mimicry scenario exists between predator and prey in which prey resembles the form, behaviour or signals exhibited by the predator to avoid or reduce risk of predation. In the Lepidoptera, there are many micromoth taxa that are phylogenetically unrelated and geographically widespread exhibiting colour patterns that are putatively involved in jumping spider mimicry. In the present study, we aimed to answer the following questions: (1) what kinds of colour pattern and display behaviour could really allow the moths to participate in jumping spider mimicry? (2) does the moth receive different predation pressure from male and female spiders? (3) why is the mimetic moth not immediately taken by the spider? Is it really because the spider sees the moth as another spider? (4) Is there any evidence justifying any visual signal displayed by the moth participated in the jumping spider mimicry? The experimental results showed that the predation rates on mimetic moths of jumping spider were significantly lower than the non-mimetic moths, and spiders exhibited specific behaviour that was displayed for conspecific communication. But not all the presuming mimicking moths can decrease predation from the spiders. Female spiders show significantly higher predation rate to the mimicking moths, while male spiders tend to display more frequently to the moth. In behaviour comparison test in male jumping spiders, we found the behaviour displayed toward mimicking moths are closer to conspecific or heterospecific female spiders, suggesting that female spiders are more likely to be the model of the mimicry systems. Previous studies have shown that UV and fluorescent signals are important in courting behaviour of jumping spider, so we block the UV reflectance signals on the wing pattern of the mimetic moths. The results show that the predation rate of moths without the UV signals is significantly higher than control group which blocked the non-ultraviolet patterns. However, there were still several jumping spiders displayed to the UV-blocking moth, suggesting the UV signals are not the only feature participate in the jumping spider mimicry system.

Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on Jan. 7, 2010. Major professor: Helen Yu. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Electrical Engineering." "2009." Includes bibliographical references (p. 82-83).

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This thesis investigated the monitoring and analysis of signals related to the vibration of large rotary blasthole drills. The research focused on a machine with electric drilling actuators: such machines are used as primary production equipment in the drill‐and‐blast cycle of the surface (open‐pit) mining process. The performance of such machines is limited by the onset of severe vibrations, which can arise due to the interaction of geology, bit, drill string, machine structure, and control settings. Experimental data for the thesis were obtained during field periods at an iron ore mine in Minnesota’s Mesabi Iron Range. The data acquisition and signal analysis techniques which were utilized are presented, including smoothing of signals and calculated variables such as specific energy. Ambient vibration sources and vibration aliasing issues are investigated. Results from analyzing structural response tests indicate that, as expected, the natural frequency of the drill mast decreases with increasing bit depth – although the mounting position of accelerometers distorts this trend. The pull down force (weight on bit) is shown to have no appreciable impact on the mast’s natural frequency, nor on the mast’s damping ratio. A strong relationship between rotary speed and the dominant vibration frequency peaks at 3x and 6x rotary speed is demonstrated, and a physical explanation of the 6x vibration peak is postulated. The rotary motor current is shown to consistently exhibit frequency peaks at 3x and 6x rotation speed, indicating that this variable is a good candidate for use either as a substitute for accelerometer feedback, or as an auxiliary signal to detect down‐the‐hole vibration when it is not manifested by the mast mounted accelerometers. System identification is used to demonstrate that the dynamic relationship between vibration and rotary current, while it can be modeled locally, varies with depth and geology and hence is essentially a time‐varying process. This results in the amplitude of rotary current not being usable as a proxy for vibration amplitude. Nonetheless, it is demonstrated that the root‐mean‐square (RMS) of the low frequency current oscillations, in a nonlinear combination with the RMS of the current signal as a whole, may be able to serve as a proxy for the RMS of the vibration signal. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2010-09-27 12:15:07.644