scholarly journals EO Sensor Planning for UAV Engineering Reconnaissance Based on NIIRS and GIQE

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Jingbo Bai ◽  
Yangyang Sun ◽  
Liang Chen ◽  
Yufang Feng ◽  
Jianyong Liu
Keyword(s):  
Image Quality ◽  
Unmanned Aerial Vehicles ◽  
Rating Scale ◽  
Geometrical Property ◽  
Quantitative Relationship ◽  
Flight Altitude ◽  
Sensor Planning ◽  
Visible Image ◽  
Sensor Performance ◽  
Information Interpretation

When unmanned aerial vehicles (UAVs) support the Corps of Engineers in reconnaissance operations, in order to gather visible image information that should meet the mission’s need, we grouped the engineering reconnaissance information interpretation tasks into 10 levels by using the National Imagery Interpretability Rating Scale (NIIRS). The quantitative relationship between the engineering targets, sensor performance, and flight altitude was established through the general image quality equation (GIQE) and the geometrical property of the ground sampled distance (GSD). Through some simulations, the influence of variable factors of the EO sensor imaging quality was analyzed, and the imaging height of the sensor for an engineering reconnaissance scenario was calculated. The results showed that this study could solve the problem of poor image quality caused by the flight altitude not meeting the mission requirements.

Improvement of image quality applying iterative scatter correction for grid-less skeletal radiography in trauma room setting

2019 ◽  
Vol 61 (6) ◽  
pp. 768-775
Author(s):  
Christoph G Lisson ◽  
Catharina S Lisson ◽  
Daniel Vogele ◽  
Beatrice Strauss ◽  
Konrad Schuetze ◽  
...  
Keyword(s):  
Image Quality ◽  
Rating Scale ◽  
Scatter Correction ◽  
Iterative Algorithms ◽  
Trauma Room ◽  
Body Regions ◽  
Wide Range ◽  
Characteristics Analysis ◽  
Skeletal Radiography ◽  
The Future Method

Background Iterative reconstruction is well established for CT. Plain radiography also takes advantage of iterative algorithms to reduce scatter radiation and improve image quality. First applications have been described for bedside chest X-ray. A recent experimental approach also provided proof of principle for skeletal imaging. Purpose To examine clinical applicability of iterative scatter correction for skeletal imaging in the trauma setting. Material and Methods In this retrospective single-center study, 209 grid-less radiographs were routinely acquired in the trauma room for 12 months, with imaging of the chest (n = 31), knee (n = 111), pelvis (n = 14), shoulder (n = 24), and other regions close to the trunk (n = 29). Radiographs were postprocessed with iterative scatter correction, doubling the number of images. The radiographs were then independently evaluated by three radiologists and three surgeons. A five-step rating scale and visual grading characteristics analysis were used. The area under the VGC curve (AUCVGC) quantified differences in image quality. Results Images with iterative scatter correction were generally rated significantly better (AUCVGC = 0.59, P < 0.01). This included both radiologists (AUCVGC = 0.61, P < 0.01) and surgeons (AUCVGC = 0.56, P < 0.01). The image-improving effect was significant for all body regions; in detail: chest (AUCVGC = 0.64, P < 0.01), knee (AUCVGC = 0.61, P < 0.01), pelvis (AUCVGC = 0.60, P = 0.01), shoulder (AUCVGC = 0.59, P = 0.02), and others close to the trunk (AUCVGC = 0.59, P < 0.01). Conclusion Iterative scatter correction improves the image quality of grid-less skeletal radiography in the clinical setting for a wide range of body regions. Therefore, iterative scatter correction may be the future method of choice for free exposure imaging when an anti-scatter grid is omitted due to high risk of tube-detector misalignment.

Evaluation of disturbance effect on geese caused by an approaching unmanned aerial vehicle

2019 ◽  
Vol 30 (2) ◽  
pp. 169-175 ◽  
Author(s):  
MADS BECH-HANSEN ◽  
RUNE M. KALLEHAUGE ◽  
JANNIK M. S. LAURITZEN ◽  
MATHIAS H. SØRENSEN ◽  
BJARKE LAUBEK ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Unmanned Aerial Vehicle ◽  
Initial Disturbance ◽  
Flight Altitude ◽  
Aerial Vehicles ◽  
Disturbance Effects ◽  
Vigilance Behaviour ◽  
Aerial Vehicle

SummaryUnmanned aerial vehicles (UAVs) are useful tools in ornithological studies. Importantly, though, UAV-caused disturbance has been noted to vary among species. This study evaluated guidelines for UAVs as a tool for researching geese. Twenty-four flocks of foraging geese were approached at an altitude of 50–100 m with a quadcopter UAV and disturbance effects were analysed across different horizontal distances between the UAV and the flocks. Geese were increasingly disturbed when approached by a UAV, with birds showing increased vigilance behaviour within approximately 300 m. Increasing UAV flight altitude as well as increasing take-off distance from the flocks both decreased the risk of bird flocks flushing. In conclusion, when monitoring geese using UAVs, flight altitudes of 100 m and take-off distances of ideally ∼500 m are recommended, to minimise initial disturbance and reducing the risk of birds flushing.

Effect of dose on image quality in a detector‐based dual‐exposure, dual‐energy system for chest radiography

2005 ◽  
Vol 46 (1) ◽  
pp. 41-47 ◽  
Author(s):  
T. Freund ◽  
F. Fischbach ◽  
U. Teichgraeber ◽  
E. Lopez Haenninen ◽  
H. Eichstaedt ◽  
...  
Keyword(s):  
Image Quality ◽  
Chest Radiography ◽  
Rating Scale ◽  
Energy System ◽  
Dual Energy ◽  
Motion Artifacts ◽  
Prototype System ◽  
Bone Structures ◽  
Dose Levels

Purpose: To assess the image quality of subtracted soft tissue and bone images of a CsI‐detector‐based dual‐energy system for chest radiography at varying dose levels. Material and Methods: We evaluated a CsI‐detector‐based, dual‐exposure, dual‐energy prototype system; 126 patients were categorized into groups of small, medium, and large. Fixed values were applied for mAs and mA. The patients were randomized into two groups with intended higher and lower speed pairs of approximately 400/1000 (high and low energy shot) and 200/500, respectively. True speed equivalents were calculated retrospectively using the detector dose. Image quality was evaluated by two highly experienced radiologists in consensus applying a rating scale of 1 to 5 for quality indicators such as image noise, residual bone structures, motion artifacts, and others. Results: Significantly decreased noise and a significant improvement for display of bone details in the bone image were noted with the higher dose, whereas a significant increase in motion artifacts reduced image quality at the higher dose. Conclusion: Radiation dose did not significantly influence the perception of dual‐energy image quality. Dual‐energy subtraction, as described, has the potential to become a future routine application in chest radiography.

Lung nodule detection in pediatric chest CT: Quantitative relationship between image quality and radiologist performance

2011 ◽  
Vol 38 (5) ◽  
pp. 2609-2618 ◽  
Author(s):  
Xiang Li ◽  
Ehsan Samei ◽  
Huiman X. Barnhart ◽  
Ana Maria Gaca ◽  
Caroline L. Hollingsworth ◽  
...  
Keyword(s):  
Image Quality ◽  
Lung Nodule ◽  
Quantitative Relationship ◽  
Chest Ct ◽  
Lung Nodule Detection ◽  
Nodule Detection ◽  
Pediatric Chest

scholarly journals Influence of wind disturbances and nonlinearities of servo drive on the contour of stabilization of the flight of height of unmanned aerial vehicle

2019 ◽  
pp. 23-30
Author(s):  
V. A. Malkin ◽  
I. V. Rozhkov ◽  
A. A. San’ko
Keyword(s):  
Mathematical Model ◽  
Comparative Analysis ◽  
Unmanned Aerial Vehicles ◽  
Control Systems ◽  
Velocity Vector ◽  
Flight Altitude ◽  
Servo Drive ◽  
Automatic Control Systems ◽  
Aerial Vehicles ◽  
Aerial Vehicle

The article discusses a mathematical model of wind, taking into account its stochastic component and wind of a steady direction, presents the results of a comparative analysis of the effect of wind parameters on the total wind velocity vector acting on unmanned aerial vehicles (UAV). The main non-line arities of the autopilot servo elements and their influence on the output signal are considered. The reaction of the contour of the UAV flight altitude stabilization to the wind is considered, taking into account the nonlinearity of the servo drive elements. Proved the need to take into account the wind in the synthesis of automatic control systems (ACS) and the contours of the angular stabilization of the drone at stages where the flight speed of the drone is less than 30 m / s.

scholarly journals COMPARATIVE STUDY OF THE DIFFERENT VERSIONS OF THE GENERAL IMAGE QUALITY EQUATION

2019 ◽  
Vol IV-2/W5 ◽  
pp. 493-500 ◽  
Author(s):  
A. Q. Valenzuela ◽  
J. C. G. Reyes
Keyword(s):  
Image Processing ◽  
Image Quality ◽  
Paradigm Shift ◽  
Rating Scale ◽  
Signal To Noise Ratio ◽  
National Image ◽  
Image Processing Techniques ◽  
Quality Rating ◽  
Processing Techniques ◽  
Image Quality Rating

<p><strong>Abstract.</strong> The General Image Quality Equation (GIQE) is an analytical tool derived by regression modelling that is routinely employed to gauge the interpretability of raw and processed images, computing the most popular quantitative metric to evaluate image quality; the National Image Interpretability Rating Scale (NIIRS). There are three known versions of this equation; GIQE&amp;nbsp;3, GIQE&amp;nbsp;4 and GIQE&amp;nbsp;5, but the last one is scarcely known. The variety of versions, their subtleties, discontinuities and incongruences, generate confusion and problems among users. The first objective of this paper is to identify typical sources of confusion in the use of the GIQE, suggesting novel solutions to the main problems found in its application and presenting the derivation of a continuous form of GIQE&amp;nbsp;4, denominated GIQE&amp;nbsp;4C, that provides better correlation with GIQE&amp;nbsp;3 and GIQE&amp;nbsp;5. The second objective of this paper is to compare the predictions of GIQE&amp;nbsp;4C and GIQE&amp;nbsp;5, regarding the maximum image quality rating that can be achieved by image processing techniques. It is concluded that the transition from GIQE&amp;nbsp;4 to GIQE&amp;nbsp;5 is a major paradigm shift in image quality metrics, because it reduces the benefit of image processing techniques and enhances the importance of the raw image and its signal to noise ratio.</p>

scholarly journals ANALYSIS OF THE IMAGE QUALITY OF NO GROUND CONTROLLED POSITIONING PRECISION ABOUT SURVEYING AND MAPPING SATELLITE

2018 ◽  
Vol XLII-3 ◽  
pp. 1821-1825
Author(s):  
Y. Wang ◽  
X. Hu ◽  
X. Yang ◽  
G. Xie
Keyword(s):  
Image Quality ◽  
Modulation Transfer Function ◽  
Signal To Noise Ratio ◽  
Quantitative Relationship ◽  
Modulation Transfer ◽  
Key Factors ◽  
Positioning Accuracy ◽  
Positioning Precision ◽  
Mismatch Rate

The image quality of the surveying camera will affect the stereoscopic positioning accuracy of the remote sensing satellite. The key factors closely related to the image quality are Modulation Transfer Function(MTF),Signal to Noise Ratio(SNR) and Quantization Bits(QB). In “Mapping Satellite-1” image as the background, research the effect of positioning precision about the image quality in no ground controlled conditions, and evaluate the quantitative relationship with the positioning precision. At last verify the validity of the experimental results by simulating three factors of the degraded data on orbit, and counting the number of matching points, the mismatch rate, and the matching residuals of the degraded data. The reason for the variety of the positioning precision was analyzed.

Fusion of Infrared and Visible Image Based on Target Regions for Environment Perception

2011 ◽  
Vol 128-129 ◽  
pp. 589-593 ◽  
Author(s):  
Yi Feng Niu ◽  
Sheng Tao Xu ◽  
Wei Dong Hu
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Target Recognition ◽  
Discrete Wavelet ◽  
Infrared Images ◽  
Target Information ◽  
Visible Image ◽  
Fused Image ◽  
Fusion Methods ◽  
Visible Images ◽  
Environment Perception

Infrared and visible image fusion is an important precondition to realize target perception for unmanned aerial vehicles (UAV) based on which UAV can perform various missions. The details in visible images are abundant, while the target information is more outstanding in infrared images. However, the conventional fusion methods are mostly based on region segmentation, and then the fused image for target recognition can’t be actually acquired. In this paper, a novel fusion method of infrared and visible image based on target regions in discrete wavelet transform (DWT) domain is proposed, which can gain more target information and preserve the details. Experimental results show that our method can generate better fused image for target recognition.

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