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1.
J Acoust Soc Am ; 148(3): 1456, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33003845

ABSTRACT

In recent years, the current technological improvements of unmanned aerial vehicles (UAV) have made drones more difficult to locate using optical or radio-based systems. However, the sound emitted by UAV motorization and the aerodynamic whistling of the UAVs can be exploited using a microphone array and an adequate real time signal processing algorithm. The proposed method takes advantage of the characteristics of the sound emitted by the UAV. The intrinsic harmonic structure of the emitted sound is exploited by a pitch detection algorithm coupled with zero-phase selective bandpass filtering to detect the fundamental of the signal and to extract its specific harmonics. Although three-dimensional position errors are less when signals are filtered within the antenna bandwidth, experimental measurements show that accurate estimates with only a few selected harmonics in the signal can be obtained with the localization process. Kalman filtering is used to smooth the estimates.

2.
J Med Case Rep ; 4: 305, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20843352

ABSTRACT

INTRODUCTION: Adult Growth hormone Deficiency is a well known phenomenon effecting both males and females. Adult Growth Hormone Deficiency is marked by a number of neuropsychiatric, cognitive performance, cardiac, metabolic, muscular, and bone symptoms and clinical features. There is no known standardized acceptable therapeutic modality to treat this condition. A recent meta-analysis found that after 16 years of Growth Hormone replacement therapy a large proportion of the patients still had Growth Hormone associated symptoms especially related to executive functioning. A major goal is to increase plasma levels of both insulin-like growth factor (insulin-like growth factor-1) and insulin-like growth factor binding protein 3. CASE PRESENTATION: We report a case of a 45-year-old caucasian woman with early ovarian failure for 2 years and amenorrhea since the age of 43, who presented with Adult Growth Hormone Deficiency and an IGF-1 of 126 ng/mL. Since her insulin-like growth factor-1 was lowest at 81 ng/mL, she was started on insulin-like growth factor-1 Increlex at 0.2 mg at bedtime, which immediately raised her insulin-like growth factor-1 levels to 130 ng/mL within 1 month, and 193 ng/mL, 249 ng/mL, and 357 ng/mL, after 3, 4, and 5 months, respectively, thereafter. Her insulin-like growth factor binding protein 3 continued to decrease. It was at this point when we added back the Growth Hormone and increased her Increlex dosage to 1.3 - 1.5 mg that her insulin-like growth factor binding protein 3 began to increase. CONCLUSION: It appears that in some patients with Adult Growth Hormone Deficiency, insulin-like growth factor-1 elevation is resistant to direct Growth Hormone treatment. Furthermore, the binding protein may not rise with insulin-like growth factor-1. However, a combination of Growth Hormone and insulin-like growth factor-1 treatment may be a solution.

3.
Cases J ; 3: 54, 2010 Feb 10.
Article in English | MEDLINE | ID: mdl-20181141

ABSTRACT

INTRODUCTION: Approximately 15% (more than 2 million individuals, based on these estimates) of all people with diabetes will develop a lower-extremity ulcer during the course of the disease. Ultimately, between 14% and 20% of patients with lower-extremity diabetic ulcers will require amputation of the affected limb. Analysis of the 1995 Medicare claims revealed that lower-extremity ulcer care accounted for $1.45 billion in Medicare costs. Therapies that promote rapid and complete healing and reduce the need for expensive surgical procedures would impact these costs substantially. One such example is the electrotherapeutic modality utilizing the H-Wave(R) device therapy and program.It has been recently shown in acute animal experiments that the H-Wave(R) device stimulation induces a nitric oxide-dependent increase in microcirculation of the rat Cremaster skeletal muscle. Moreover, chronic H-wave(R) device stimulation of rat hind limbs not only increases blood flow but induces measured angiogenesis. Coupling these findings strongly suggests that H-Wave(R) device stimulation promotes rapid and complete healing without need of expensive surgical procedures. CASE PRESENTATION: We decided to do a preliminary evaluation of the H-Wave(R) device therapy and program in three seriously afflicted diabetic patients. Patient 1 had chronic venous stasis for 6 years. Patient 2 had chronic recurrent leg ulcerations. Patient 3 had a chronic venous stasis ulcer for 2 years. All were dispensed a home H-Wave(R) unit. Patient 1 had no other treatment, patient 2 had H-Wave(R) therapy along with traditional compressive therapy, and patient 3 had no other therapy.For patient 1, following treatment the ulcer completely healed with the H-Wave(R) device and program after 3 months. For patient 2, by one month complete ulcer closure occurred. Patient 3 had a completely healed ulcer after 9 months. CONCLUSIONS: While most diabetic ulcers can be treated successfully on an outpatient basis, a significant proportion will persist and become infected. Based on this preliminary case series investigation we found that three patients prescribed H-Wave(R) home treatment demonstrate accelerated healing with excellent results. While these results are encouraging, additional large scale investigation is warranted before any interpretation is given to these interesting outcomes.

4.
J Acoust Soc Am ; 128(6): 3554-67, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21218888

ABSTRACT

Near-field acoustic holography (NAH) is an effective tool for visualizing acoustic sources from pressure measurements made in the near-field of sources using a microphone array. The method involving the Fourier transform and some processing in the frequency-wavenumber domain is suitable for the study of stationary acoustic sources, providing an image of the spatial acoustic field for one frequency. When the behavior of acoustic sources fluctuates in time, NAH may not be used. Unlike time domain holography or transient method, the method proposed in the paper needs no transformation in the frequency domain or any assumption about local stationary properties. It is based on a time formulation of forward sound prediction or backward sound radiation in the time-wavenumber domain. The propagation is described by an analytic impulse response used to define a digital filter. The implementation of one filter in forward propagation and its inverse to recover the acoustic field on the source plane implies by simulations that real-time NAH is viable. Since a numerical filter is used rather than a Fourier transform of the time-signal, the emission on a point of the source may be rebuilt continuously and used for other post-processing applications.


Subject(s)
Acoustics , Holography , Models, Theoretical , Signal Processing, Computer-Assisted , Acoustics/instrumentation , Computer Simulation , Equipment Design , Fourier Analysis , Holography/instrumentation , Motion , Numerical Analysis, Computer-Assisted , Pressure , Sound , Sound Spectrography , Time Factors , Transducers, Pressure
5.
Phys Rev Lett ; 85(23): 4868-71, 2000 Dec 04.
Article in English | MEDLINE | ID: mdl-11102138

ABSTRACT

The first detailed measurements of the centrality dependence of strangeness production in p-A collisions are presented. Lambda and K(S) dn/dy distributions from 17.5 GeV/ c p-Au collisions are shown as a function of "grey" track multiplicity and the estimated number of collisions, nu, made by the proton. The nu dependence of the Lambda yield deviates from a scaling of p-p data by the number of participants, increasing faster than this scaling for nu

7.
Phys Rev Lett ; 63(17): 1894, 1989 Oct 23.
Article in English | MEDLINE | ID: mdl-10040705
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