نتایج جستجو برای: acoustic pulse
تعداد نتایج: 174184 فیلتر نتایج به سال:
BACKGROUND Little is known about migration patterns and seasonal distribution away from coastal summer feeding habitats of many pelagic baleen whales. Recently, large-scale passive acoustic monitoring networks have become available to explore migration patterns and identify critical habitats of these species. North Atlantic minke whales (Balaenoptera acutorostrata) perform seasonal migrations b...
Measurements using a fiber-optic probe hydrophone, high-speed camera, and B-mode ultrasound showed attenuation of the trailing negative-pressure phase of a lithotripter shock pulse under conditions that favor generation of cavitation bubbles, such as in water with a high content of dissolved gas or at high pulse repetition rate where more cavitation nuclei persisted between pulses. This cavitat...
Distributed Acoustic Sensor (DAS) has potential in applications such as hydroacoustic detection. In this paper, a dual-pulse heterodyne distributed acoustic sensor system using semiconductor optical amplifier (SOA)-based fiber ring laser (FRL) is proposed. Unlike the previous DAS configurations, SOA-based FRL replaces narrow linewidth (NLL) and pulse modulator, reducing costs simplifying system...
Non-Destructive Testing & Evaluation methods are developed to inspect and investigate materials and structures. Ultrasonic Testing is an NDT method can be used for measuring the thickness of objects, as one of its significant applications. The objective of this paper is designing and applying an intelligent UT fuzzy control system for evaluating the thickness of thin metal objects in a range of...
OBJECTIVES To investigate the electric-acoustic interactions within the inferior colliculus of guinea pigs and to observe how central masking appears in invasive neural recordings of the inferior colliculus (IC). METHODS A platinum-iridium wire was inserted to scala tympani through cochleostomy with a depth no greater than 1 mm for intracochlear stimulation of electric pulse train. A 5 mm 100...
This paper will provide an overview of a patented acoustic technique known as Acoustek ® that has been developed to detect features, such as blockages and leakages in gas pipelines. The technique involves injecting an acoustic, or pressure pulse into the gas within the pipeline. This acoustic pulse will travel as a plane wave along the pipeline and will be partially reflected wherever there is ...
Numerous fish species produce broad-band pulsed sounds with a distinct temporal patterning which is thought to be important during intraspecific communication. In order to determine whether fishes are able to utilize temporal characteristics of acoustic signals, time resolution was determined in four species of otophysines and anabantoids by analyzing auditory brainstem responses (ABRs) to doub...
BACKGROUND This study looked to validate the acoustic wave technology of the Storz-D-Actor that inflicted a consistent closed-head, traumatic brain injury (TBI) in rats. We studied a range of single pulse pressures administered to the rats and observed the resulting decline in motor skills and memory. Histology was observed to measure and confirm the injury insult. METHODS Four different acou...
Measurements of basin-scale acoustic transmissions made during the last four years by the Acoustic Thermometry of Ocean Climate (ATOC) program have allowed for the study of acoustic fluctuations of low-frequency pulse propagation at ranges of 1000 to 5000 km. Analysis of data from the ATOC Acoustic Engineering Test conducted in November 1994 has revealed new and unexpected results for the physi...
Shoreward pulses of cold, high salinity, phytoplankton-rich bottom water represent short time scale changes in nearshore hydrography and biological community structure off the leeward coast of Oahu, Hawaii. A three-week mooring deployment in Spring 2009 revealed that ‘cold pulses’ occurred over all phases of the semidiurnal surface tide, but that a statistically greater proportion occurred at l...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید