In ultrasound images, clutter is a noise artifact most easily observed in anechoic or hypoechoic regions. It appears as diffuse echoes overlying anatomical structures of diagnostic importance, obscuring tissue borders and reducing image contrast. A novel clutter reduction method for abdominal images is proposed, ...
PubMed Central
In this article, we present an adaptive clutter rejection method for selecting different clutter filters in ultrasound color flow imaging. A single clutter filter is typically used to reject the clutter. Because the clutter characteristics vary in both space and time, the single ...
PubMed
... Title : Single Ping Clutter Reduction: Segmentation Using Markov Random Fields. ... of image segmentation based on a Markov random field model to ...
DTIC Science & Technology
... Accession Number : ADD008548. Title : Radar Clutter Reduction by Use of Frequency-Diverse, Wideband Pulse-Compression Waveforms. ...
... Accession Number : AD0742917. Title : An Application of Digital Filters for Radar Clutter Reduction. Descriptive Note : Master's thesis,. ...
... Title : A Study of Clutter Reduction Techniques in Wide Bandwidth HF/VHF Deep Ground Penetrating Radar. Descriptive Note : Master's thesis. ...
... In terms of visual clutter, it is important to be aware of how a ... color scheme using these colors (in order): red, orange, yellow, green, blue, purple. ...
... measured at Milwaukee airport during the spring bird migration period. Chapter 4 devribes angel clutter reduction techniques which can exploit ...
A method is given for generating and transmitting wideband, expanded radar pulses which spatially decorrelate clutter and are frequency-hopped from pulse to pulse by the proper frequency difference for clutter decorrelation by frequency-diversity. The ret...
National Technical Information Service (NTIS)
Hot clutter consists of jammer signals which have been reflected in the ground or sea before they are received by a radar. This is a significant problem in current military airborne radar systems. There are several proposed ways to suppress hot clutter. L...
... is then displayed on a plan-position-indicator (PPI) display. ... receivers, Reduction, Radar receivers, Plan position indicators, Carrier frequencies ...
This paper describes the theory and practice of ground penetrating radar (GPR) clutter characterization and removal. Clutter and target parametric and non-parametric modeling methods are described and results of these methods on laboratory data are presented. Data were collected at the Technische Universitaet Ilmenau using a 6 GHZ frequency- stepped GPR. ...
NASA Astrophysics Data System (ADS)
... Models for volume scattering: atmospheric, ionospheric, chaff. Models for target scattering; RCS reduction or modification techniques. ...
... Experimental results also show that RCS matrix data is used ... MATHEMATICS), RADAR REFLECTIONS, DATA REDUCTION, FORMATS, TARGET ...
... The use of brush rakes without magnets has proven to be successful in Sri Lanka to expose the top of shallow mines. Here ...
Page 1. GAUSSIAN MIXTURE REDUCTION FOR BAYESIAN TARGET TRACKING IN CLUTTER THESIS David J. Petrucci, Captain, USAF ...
... Title : Doppler Aliasing Reduction on Wide-Angle Synthetic Aperture Radar ... When the received RCS scattered hot clutter waveform is perfectly ...
This is the final TSC report on our overview of the TAGSEA sea clutter measurement program. It includes some general comments on the techniques used by Raytheon and General Dynamics in obtaining the data, the data reduction, and test results. Since the ea...
The use of low frequency active sonar in shallow water leads to large numbers of clutter detections. This high false alarm rate can overload automatic tracking and classification algorithms. Traditional detection algorithms operate on each beam output ind...
The work considers a new polarization method for possible reduction of rain clutter in monostatic radar. Basically, the proposed technique attempts to adjust the effective polarization of the receiver to match the average polarization of backscattered fie...
The global land mine crisis is creating immense social and economic problems worldwide. Safe and cost effective methods for clearing these mines are therefore needed. A promising sensor for detecting small anti-personnel mines is the ground penetrating radar (GPR). However, GPR performs inadequately due to clutter which dominates the return and obscures the mine information. ...
Reducing clutter is one of the most daunting problems a radar processing engineer faces. Clutter causes a significant problem when attempting to detect sub-surface targets, as any significant change in the ground dielectric will produce a return at the re...
... The transmitter consists of a stationary bow-tie antenna and an amplifier. The ... The bow-tie topology was chosen because of its large beamwidth. ...
A method for reducing ground clutter contribution from ground penetrating radar (GPR) data is proposed for discrimination of landmines located in shallow depth. The algorithm of this method is based on the Matching Pursuit (MP) that is a technique for non-orthogonal signal decomposition using dictionary of functions. As the dictionary of function, a wave-based dictionary ...
This paper presents statistical signal processing approaches for clutter reduction in Stepped-Frequency Ground Penetrating Radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches are successfully evaluated and compared on real ...
E-print Network
Some results on autocorrelation and cross-correlation properties of binary phase-coded radar waveforms are presented. The results are applied to a consideration of RFI reduction between radars and to questions of clutter suppression capability. (Author)
A computer simulation conducted by MITRE indicated that an automatic clutter eliminator (ACE) using correlation information within the clutter sum register of the common digitizer (CD) could be used to improve target detection and reduce false targets due to radar weather clutter. A real time hardware device was fabricated to perform ...
The generation of a posteriori distribution of a statistic of propagation loss conditioned on observed radar sea clutter is described. The statistic u is the 20th percentile level of the two-way propagation loss at a 5-m height over the 10-60 km range interval. A discrete implementation of the Bayesian paradigm is employed. The forward mapping from the space of environmental ...
... Key Words: radar clutter, propagation, sea clutter, land clutter, littoral clutter, shipboard, model SUMMARY & CONCLUSIONS ...
... 3.4 Gibbs Random Fields A set of random variables W is said to be a Gibbs random field (GRF) on S with respect to ... 3.5 Markov-Gibbs equivalence ...
Through-wall imaging (TWI) is important from the point of view of rescue operations and surveillance. Several researchers have been working in this field but have still not obtained any concrete results. TWI using narrow band radar faces the problem of low resolution whereas ultra-wideband (UWB) radar provides better resolution, classification and low loss for the imaging signals. TWI faces many ...
Methods and systems reduce clutter interference in a radar-responsive tag system. A radar transmits a series of linear-frequency-modulated pulses and receives echo pulses from nearby terrain and from radar-responsive tags that may be in the imaged scene. Tags in the vicinity of the radar are activated by the radar's pulses. The tags receive and remodulate the radar ...
Energy Citations Database
... relative abdominal volume. Further, a reduction in abdominal volume may reduce water uptake by eggs in utero (Qualls and ... an apparent evolutionary imperative for flatter females to reduce clutch volume...
NBII National Biological Information Infrastructure
A device that generates negative extra-abdominal pressure (ABDOPRE) for treatment of patients with high intra-abdominal pressure was developed. It includes pressure sensors for transducing intra-abdominal pressure through an intra-vesical catheter and negative pressure in the vacuum bell which is placed over the abdomen. By means of a ...
In this report the clutter-rejection performance of a range-ambiguous MTI and doppler-filter system is analyzed. The reduction of correlation time in a range-ambiguous system in general improves the clutter-rejection performance. However, due to the fold over phenomenon, a faraway target has to compete with the near-in ...
This paper addresses the problem of detecting anti-personnel landmines using features extracted via the fractional Fourier transform. A preliminary clutter reduction system is used to reduce the effects of ground clutter. The processed signatures are then examined using the fractional Fourier transform, where pertinent target features ...
... Title : Radar Clutter Modeling. ... Descriptors : , (*RADAR CLUTTER, SIMULATION), MATHEMATICAL MODELS, SCATTERING, NOISE(RADAR). ...
... Radar Ground Clutter at 42 Sites ... LABORATORY MULTIFREQUENCY MEASUREMENTS OF RADAR GROUND CLUTTER AT 42 SITES ...
... DEFENCE D�FENSE & Measurements and analysis of reverberation and clutter data ... Measurements and analysis of reverberation and clutter data ...
... Different methods for calculating the relative clutter based on the magnitude of the ... The relative clutter is used to calculate probability of ...
... Seismic reflection data across the clutter location showed that the clutter is associated with buried mud volcanoes (see Fig 2a). ...
... AN OTH RADAR CLUTTER SIMULATION I I I ! I S ... arriving at an understanding of OTH radar clutter originating in the equatorial ionosphere. ...
... strength and isolate individual clutter features, confirming hypotheses about the mechamism leading to clutter in areas of submarine mud volcanoes ...
... Abstract : The report analyzes current radar clutter models and examines the criteria by which they are applied in the prediction of radar clutter ...
... Title : A Model for Space Radar Clutter. ... Abstract : A model for radar clutter as encountered from a space-based platform is developed. ...
In radar imaging, for example Inverse Synthetic Aperture Radar (ISAR) imaging, a target can be modeled as a collection of scattering centers in the image domain. A method to improve radar image quality through clutter suppression and localization of scattering centers is presented in this paper. The approach is based on localizing the scattering centers by enforcing sparsity ...
Clutter parameters are discussed and two different elaborations of prevailing clutter theories are presented. It is shown that polarimetric wideband measurements permit clutter classification.
The note provides an introduction to clutter from land, weather and birds and summarises the present state of knowledge about various clutter characteristics such as the probability distributions of clutter cross-sections and spectral distributions. It al...
This article describes meteospazmil clinical effectiveness in problem of abdominal pain syndrome and flatulence reduction at IBS and gastrointestinal diseases that are attended with secondary colon motor disorders. PMID:19961001
legs consist of bone, muscle, fat, and skin. There are additional lung, abdominal, and brain tissues in the torso and head zones. The model calculates the conduction heat...
National Renewable Energy Laboratory (NREL)
... in this application is to induce and maintain a reduction of excess visceral abdominal fat in human immunodeficiency virus (HIV)-infected patients ...
Center for Biologics Evaluation and Research (CBER)
We report the case of a paraduodenal hernia treated by reduction of the hernia and closure of the hernial orifice. PMID:15912984
A major challenge in sounding of fast-flowing glaciers in Greenland and Antarctica is surface clutter, which masks weak returns from the ice-bed interface. The surface clutter is also a major problem in sounding and imaging sub-surface interfaces on Mars and other planets. We successfully applied array-processing techniques to reduce ...
Weather radars are usually sited so they can survey as large an area as possible. A large surveillance area is achieved by placing the antenna as high as practical but then the radar can be blind to weather targets near the ground because of ground clutter interference. There are applications where it is necessary to have fine resolution of low altitude divergence and wind ...
The paper presents results from a bistatic SAR experiment conducted using two airborne SAR systems operating in the high VHF- and low UHF-band. The Swedish SAR system LORA operated together with the French SAR system SETHI and collected data in different bistatic geometries in the frequency band 222-460 MHz and using HH-polarization. The two SAR systems were synchronized using the 1PPS GPS-signal. ...
A 3-wk-old male, with abdominal distention and severe hypoproteinemia from poor nutrition, underwent a study that showed a persistent diffuse abdominal uptake of Ga-67 citrate, indicating pyogenic or tuberculous peritonitis. However, there were no corresponding clinical or laboratory findings. After a 1-wk course of hyperalimentation with albumin, ...
Advanced radar receivers having an instantaneous dynamic range exceeding 90 dB are currently under development. These receivers must operate linearly to achieve satisfactory performance in a severe clutter environment. Presently available, state-of-the-art analog-to- digital converters (ADCs) having sufficiently high sampling rates do not have adequate dynamic ranges to ...
... Studies on Sonar Clutter and Reverberation ... Assess capability of directional arrays for inversion and reverberation studies ...
... Page 4. Semiannual Report NEAR INFRARED BACKGROUND CLUTTER AND ATMOSPHERIC TRANSMISSION INSTRUMENTATION by ...
... Title : EVALUATION OF RAIN CLUTTER. ... FUZES, *RADAR INTERFERENCE, ATMOSPHERIC PRECIPITATION, CHEMICAL PRECIPITATION ...
... Determining the Characteristics and Mechanisms for Clutter and Environmental Reverberation and their Impact on Long Range Sonar Performance ...
... Accession Number : AD0709105. Title : A COORDINATED EXPERIMENT ON RADAR CLUTTER AND AURORAL PARTICLE FLUXES. ...
The report analyzes current radar clutter models and examines the criteria by which they are applied in the prediction of radar clutter performance. The fundamentals of radar detection theory are reviewed in order to devise a more appropriate clutter mode...
A microwave imaging approach is simulated and validated experimentally that uses a small, wideband adaptive array. The experimental 12-element linear array and microwave receiver uses stepped frequency CW signals from 2--3 GHz and receives backscattered energy from short range objects in a +/-90� field of view. Discone antenna elements are used due to their wide temporal bandwidth, isotropic ...
The U.S. Army Research, Development and Engineering Command at Redstone Arsenal, Alabama have developed a dual mode, Ka Band Radar and IIR system for the purpose of data collection and tracker algorithm development. The system is comprised of modified MMW and IIR sensors and is mounted in a stabilized ball on a UH-1 helicopter operated by Redstone Technical Test Center. Several missile programs ...
. This technique has been applied to both simple point plots and parallel coordinate plots. In practice, the sub-sampling). The user can therefore investigate dense regions of a plot by reducing the lens sampling rate the context of the lens region within the overall plot. In addition to its sampling control, which
... Although there are various types of ionospheric clutter, in this study we concentrate only on the sporadic-E (Es) ionospheric clutter. ...
... 8-I Stochastic-Constraints Method in Nonstationary Hot-Clutter ... since the hot- and cold-clutter signals are mutually independent. Correspondingly, ...
... Title : Statistical Characterization of Fish School Clutter. ... sonar systems which can account for the non-Rayleigh nature of clutter from fish schools. ...
... SIDELOBE CANCELLER JAMMING USING HOT-CLUTTER by ... NUMBER OF PAGES 129 14. SUBJECT TERMS Sidelobe Canceller, Hot-clutter 16. ...
... Technical Documnent 1809 May 1990 Radar Clutter Via ... I. INTRODUCTION 1 In a recent study , radar clutter results calculated via waveguide ...
The method is designed for suppressing clutter in a radar system. A visual indicator is provided for adjusting the setting of a variable frequency oscillator thereby eliminating the presentation of clutter on a radar scope. A spectrum analyzer shows both ...
... Accession Number : AD0834960. Title : RADAR CLUTTER IN AN AIR DEFENSE SYSTEM. PART 1. CLUTTER PHYSICS,. ...
Page 1. Fusion of Distributions for Radar Clutter Modeling ... 4. TITLE AND SUBTITLE Fusion of Distributions for Radar Clutter Modeling 5a. ...
... 5. FUNDING NUMBERS EFFECT OF CELL SIZE ON RADAR CLUTTER STATISTICS ... fs NMLOM OF PAMS 30 Radar clutter, Enhanced backscatter ...
Page 1. Acoustic Clutter in Continental Shelf Environments ... 4. TITLE AND SUBTITLE Acoustic Clutter in Continental Shelf Environments 5a. ...
... Accession Number : ADA539416. Title : A Probabilistic Model of the Radar Signal-to-Clutter and Noise Ratio for Weibull-Distributed Clutter. ...
... searched maps of high, medium, or low global clutter for a target in a high or low local clutter region. Global and local clutter influenced search time ...
Multiplicative noise poses a big challenge for SAR imaging system, in which energy from the sidelobes of large RCS man-made and natural clutter objects spread throughout the resulting SAR imagery. Detection of small RCS targets is very difficult since their signatures might be obscured or even embedded in this multiplicative noise floor that is proportional to the RCS of ...
One to four per cent of all deaths in patients over 65 are caused by aneurysmatic diseases of the abdominal or thoracic aorta. For elective surgery in abdominal aneurysms, open surgery and endovascular treatment both demonstrate brilliant overall results. In the thoracic aorta, new endovascular procedures have led to considerable ...
To estimate the risk and population attributable risk of prehypertension that is due to abdominal obesity in White, Black and Hispanic American adults. To determine how much of the relative difference in the risk of prehypertension between high-risk Blacks and Hispanics and the low-risk group Whites that is attributable to their differences in abdominal ...
This paper describes applications of maximum likelihood adaptive neural system (MLANS) to the characterization of clutter in IR images and to the identification of targets. The characterization of image clutter is needed to improve target detection and to enhance the ability to compare performance of different algorithms using diverse imagery data. ...
Robust detection of small targets is very important in IRST (Infrared Search and Track). This paper presents a novel mathematical method for the incoming target detection problem in cluttered background motivated from the robust properties of human visual system (HVS). The HVS shows the best efficiency and robustness for an object detection task. The robust properties of the ...
The relationship between excess abdominal adipose tissue, metabolic and cardiovascular health risk has stimulated interest in the efficacy of physical activity in specifically perturbing this adipose depot. The evolution of imaging techniques has enabled more direct measurement of changes in abdominal and visceral fat. The purpose of this summary was to ...
BackgroundDevelopment of abdominal compartment syndrome (ACS) in patients with severe acute pancreatitis (SAP) has a strong impact on the course of disease. Number of patients with this complication increases during the years due more aggressive fluid resuscitation, much bigger proportion of patients who is treated conservatively or by minimal invasive approach, and efforts to ...
Restricted ability of triangulation, a highly flexible intestine, as well as limited control and overview over the abdominal organs, complicated extensive abdominal interventions in the past. Thus, additional access sites were needed to allow sufficient interoperative control. The newly developed snake charmer NOTES-technique enables the ...
A Petit lumbar hernia is an uncommon hernia. Congenital forms are seen in children. Incarceration may occur as an unreducible lumbar mass, associated with bilious vomiting and abdominal distention. Abdominal X-ray shows sided-wall bowel gas. In this case, reduction and primary closure must be performed as emergency repair. ...
Early definitive closure of abdominal wall defects is possible in most cases. Staged reduction does offer distinct advantages, and mortality and morbidity may be better. Risk stratification may produce outcome and tailor management of difficult cases in the form of a clinical pathway. Stem cell technology may, in the future, offer the ideal allogenic ...
cleaning efforts are diluted or impossible in cluttered classrooms. Clutter Management Recommendations 1 for learning is to be applauded, not discouraged. However, if these materials are not managed carefully on a daily basis, and are allowed to accumulate over time within classrooms and storage areas, a condition
The paper analyzes the origin and features of radar clutter echo, indicates that the parametric spectral estimation method is more reasonable in setting up clutter models and more convenient in simulating clutter process than classical periodogram method....
