[Phantom studies of ultrasound equipment for quality improvement in breast diagnosis].
Madjar, H; Mundinger, A; Lattermann, U; Gufler, H; Prömpeler, H J
1996-04-01
According to the German guidelines for quality control of ultrasonic equipment, the following conditions are required for breast ultrasound: A transducer frequency between 5-7.5 MHz and a minimum field of view of 5 cm. Satisfactory images must be obtained in a depth between 0.5 and 4 cm with a wide tolerance of the focal zones. This allows the use of poor quality equipment which does not produce satisfactory image quality and it excludes a number of high frequency and high resolution transducers with a field of view below 5 cm. This study with a test phantom was performed to define image quality objectively. Sixteen ultrasound instruments in different price categories were used to perform standardized examinations on a breast phantom model 550 (ATS Laboratories, Bridgeport, USA). Contrast and spatial resolution in different penetration depths were investigated on cyst phantoms from 1-4 mm diameter and wire targets with defined distances between 0.5-3 mm 4 investigations reported the images. A positive correlation was seen between price category and image quality. This study demonstrates that transducer frequency and image geometry do not allow sufficient quality control. An improvement of ultrasound diagnosis is only possible if equipment guidelines are based on standard examinations with test phantoms.
Trained nurses can obtain satisfactory bone marrow aspirates and trephine biopsies.
Lawson, S; Aston, S; Baker, L; Fegan, C D; Milligan, D W
1999-01-01
AIMS: To assess the feasibility of training nurse practitioners to perform bone marrow aspiration and trephine biopsy, and to compare the quality of these samples with those obtained by medical staff. METHODS: A retrospective audit was undertaken of nurse practitioner and medical staff performance in bone marrow procedures in a busy haematology day unit. RESULTS: Nurse practitioners fared favourably in comparison with medical staff in performing bone marrow trephine biopsies, with mean biopsy lengths of 11 mm and 10.7 mm respectively. However, only 78% of the smears obtained by the nurses were judged technically satisfactory, compared with 91% prepared by doctors. This discrepancy was thought to be due largely to the quality of slide spreading. CONCLUSIONS: With motivated staff and a structured educational and training programme it is possible for nurse practitioners to perform the techniques of bone marrow aspiration and biopsy, and obtain specimens of satisfactory quality, thus improving efficiency of the haematology day unit and increasing quality of patient care. Images PMID:10396248
DeCicco, Anthony E; Sokil, Alexis B; Marhefka, Gregary D; Reist, Kirk; Hansen, Christopher L
2015-04-01
Obesity is not only associated with an increased risk of coronary artery disease, but also decreases the accuracy of many diagnostic modalities pertinent to this disease. Advances in myocardial perfusion imaging (MPI) have mitigated somewhat the effects of obesity, although the feasibility of MPI in the super-obese (defined as a BMI > 50) is currently untested. We undertook this study to assess the practicality of MPI in the super-obese using a multi-headed solid-state gamma camera with attenuation correction. We retrospectively identified consecutive super-obese patients referred for MPI at our institution. The images were interpreted by 3 blinded, experienced readers and graded for quality and diagnosis, and subjectively evaluated the contribution of attenuation correction. Clinical follow-up was obtained from review of medical records. 72 consecutive super-obese patients were included. Their BMI ranged from 50 to 67 (55.7 ± 5.1). Stress image quality was considered good or excellent in 45 (63%), satisfactory in 24 (33%), poor in 3 (4%), and uninterpretable in 0 patients. Rest images were considered good or excellent in 34 (49%), satisfactory in 23 (33%), poor in 13 (19%), and uninterpretable in 0 patients. Attenuation correction changed the interpretation in 34 (47%) of studies. MPI is feasible and provides acceptable image quality for super-obese patients, although it may be camera and protocol dependent.
NASA Astrophysics Data System (ADS)
Akiyama, Iwaki; Yoshizumi, Natsuki; Saito, Shigemi; Wada, Yuji; Koyama, Daisuke; Nakamura, Kentaro
2012-07-01
The authors have developed a multiple frequency imaging system using a multiple resonance transducer (MRT) consisting of 1-3 composite materials with a low mechanical quality factor Q bonded together. The MRT has a structure consisting of thin and thick piezoelectric plates, two matching layers, and a backing layer. This makes it possible to obtain B-mode images of satisfactory resolution using ultrasonic pulses owing to their short duration. In this paper, the vibration property of the MRT derived through equivalent-circuit analysis is first shown. By utilizing the result, an MRT capable of transmitting ultrasonic pulses for generation of the images of biological tissues with satisfactory resolution is designed and prototyped. Setting the prototype transducer in the mechanical sector probe of commercial ultrasonic diagnosis equipment, the speckle reduction effect is demonstrated using images of various phantoms to mimic biological tissues and a human thyroid.
A vision-based weld quality evaluation system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barnett, R.J.; Cook, G.E.; Strauss, A.M.
1996-12-31
Inspection of the appearance of weld beads is an integral part of the overall welding process. Lack of satisfactory appearance in itself may be sufficient grounds for part rejection or the lack of satisfactory appearance may be used as an indirect indicator of more substantive problems such as poor fusion or subsurface cracks. In all cases the inspection process tends to be both time and labor intensive. The present research uses a video system and appropriate image capture and processing to determine the quality of the weld based upon surface appearance. This relative quality rating was compared to similar ratingsmore » performed by human inspectors and was found to give very good correlation. The system was implemented for the Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes.« less
Simulation Study of Effects of the Blind Deconvolution on Ultrasound Image
NASA Astrophysics Data System (ADS)
He, Xingwu; You, Junchen
2018-03-01
Ultrasonic image restoration is an essential subject in Medical Ultrasound Imaging. However, without enough and precise system knowledge, some traditional image restoration methods based on the system prior knowledge often fail to improve the image quality. In this paper, we use the simulated ultrasound image to find the effectiveness of the blind deconvolution method for ultrasound image restoration. Experimental results demonstrate that the blind deconvolution method can be applied to the ultrasound image restoration and achieve the satisfactory restoration results without the precise prior knowledge, compared with the traditional image restoration method. And with the inaccurate small initial PSF, the results shows blind deconvolution could improve the overall image quality of ultrasound images, like much better SNR and image resolution, and also show the time consumption of these methods. it has no significant increasing on GPU platform.
Developing Matlab scripts for image analysis and quality assessment
NASA Astrophysics Data System (ADS)
Vaiopoulos, A. D.
2011-11-01
Image processing is a very helpful tool in many fields of modern sciences that involve digital imaging examination and interpretation. Processed images however, often need to be correlated with the original image, in order to ensure that the resulting image fulfills its purpose. Aside from the visual examination, which is mandatory, image quality indices (such as correlation coefficient, entropy and others) are very useful, when deciding which processed image is the most satisfactory. For this reason, a single program (script) was written in Matlab language, which automatically calculates eight indices by utilizing eight respective functions (independent function scripts). The program was tested in both fused hyperspectral (Hyperion-ALI) and multispectral (ALI, Landsat) imagery and proved to be efficient. Indices were found to be in agreement with visual examination and statistical observations.
Chalazonitis, A N; Koumarianos, D; Tzovara, J; Chronopoulos, P
2003-06-01
Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality.
Comparison of 10 digital SLR cameras for orthodontic photography.
Bister, D; Mordarai, F; Aveling, R M
2006-09-01
Digital photography is now widely used to document orthodontic patients. High quality intra-oral photography depends on a satisfactory 'depth of field' focus and good illumination. Automatic 'through the lens' (TTL) metering is ideal to achieve both the above aims. Ten current digital single lens reflex (SLR) cameras were tested for use in intra- and extra-oral photography as used in orthodontics. The manufacturers' recommended macro-lens and macro-flash were used with each camera. Handling characteristics, colour-reproducibility, quality of the viewfinder and flash recharge time were investigated. No camera took acceptable images in factory default setting or 'automatic' mode: this mode was not present for some cameras (Nikon, Fujifilm); led to overexposure (Olympus) or poor depth of field (Canon, Konica-Minolta, Pentax), particularly for intra-oral views. Once adjusted, only Olympus cameras were able to take intra- and extra-oral photographs without the need to change settings, and were therefore the easiest to use. All other cameras needed adjustments of aperture (Canon, Konica-Minolta, Pentax), or aperture and flash (Fujifilm, Nikon), making the latter the most complex to use. However, all cameras produced high quality intra- and extra-oral images, once appropriately adjusted. The resolution of the images is more than satisfactory for all cameras. There were significant differences relating to the quality of colour reproduction, size and brightness of the viewfinders. The Nikon D100 and Fujifilm S 3 Pro consistently scored best for colour fidelity. Pentax and Konica-Minolta had the largest and brightest viewfinders.
Logarithmic profile mapping multi-scale Retinex for restoration of low illumination images
NASA Astrophysics Data System (ADS)
Shi, Haiyan; Kwok, Ngaiming; Wu, Hongkun; Li, Ruowei; Liu, Shilong; Lin, Ching-Feng; Wong, Chin Yeow
2018-04-01
Images are valuable information sources for many scientific and engineering applications. However, images captured in poor illumination conditions would have a large portion of dark regions that could heavily degrade the image quality. In order to improve the quality of such images, a restoration algorithm is developed here that transforms the low input brightness to a higher value using a modified Multi-Scale Retinex approach. The algorithm is further improved by a entropy based weighting with the input and the processed results to refine the necessary amplification at regions of low brightness. Moreover, fine details in the image are preserved by applying the Retinex principles to extract and then re-insert object edges to obtain an enhanced image. Results from experiments using low and normal illumination images have shown satisfactory performances with regard to the improvement in information contents and the mitigation of viewing artifacts.
Enhancement of low light level images using color-plus-mono dual camera.
Jung, Yong Ju
2017-05-15
In digital photography, the improvement of imaging quality in low light shooting is one of the users' needs. Unfortunately, conventional smartphone cameras that use a single, small image sensor cannot provide satisfactory quality in low light level images. A color-plus-mono dual camera that consists of two horizontally separate image sensors, which simultaneously captures both a color and mono image pair of the same scene, could be useful for improving the quality of low light level images. However, an incorrect image fusion between the color and mono image pair could also have negative effects, such as the introduction of severe visual artifacts in the fused images. This paper proposes a selective image fusion technique that applies an adaptive guided filter-based denoising and selective detail transfer to only those pixels deemed reliable with respect to binocular image fusion. We employ a dissimilarity measure and binocular just-noticeable-difference (BJND) analysis to identify unreliable pixels that are likely to cause visual artifacts during image fusion via joint color image denoising and detail transfer from the mono image. By constructing an experimental system of color-plus-mono camera, we demonstrate that the BJND-aware denoising and selective detail transfer is helpful in improving the image quality during low light shooting.
Mosavi, Firas; Laurell, Anna; Ahlström, Håkan
2015-11-01
Whole body (WB) magnetic resonance imaging (MRI), including diffusion-weighted imaging (DWI) has become increasingly utilized in cancer imaging, yet the clinical utility of these techniques in follow-up of testicular cancer patients has not been evaluated. The purpose of this study was to evaluate the feasibility of WB MRI with continuous table movement (CTM) technique, including multistep DWI in follow-up of patients with testicular cancer. WB MRI including DWI was performed in follow-up of 71 consecutive patients (median age, 37 years; range 19-84) with histologically confirmed testicular cancer. WB MRI protocol included axial T1-Dixon and T2-BLADE sequences using CTM technique. Furthermore, multi-step DWI was performed using b-value 50 and 1000 s/mm(2). One criterion for feasibility was patient tolerance and satisfactory image quality. Another criterion was the accuracy in detection of any pathological mass, compared to standard of reference. Signal intensity in DWI was used for evaluation of residual mass activity. Clinical, laboratory and imaging follow-up were applied as standard of reference for the evaluation of WB MRI. WB MRI was tolerated in nearly all patients (69/71 patients, 97%) and the image quality was satisfactory. Metal artifacts deteriorated the image quality in six patients, but it did not influence the overall results. No case of clinical relapse was observed during the follow-up time. There was a good agreement between conventional WB MRI and standard of reference in all patients. Three patients showed residual masses and DWI signal was not restricted in these patients. Furthermore, DWI showed abnormally high signal intensity in a normal-sized retroperitoneal lymph node indicating metastasis. The subsequent (18)F-FDG PET/CT could verify the finding. WB MRI with CTM technique including multi-step DWI is feasible in follow-up of patients with testicular cancer. DWI may contribute to important added-value data to conventional MRI sequences regarding the activity of residual masses.
NASA Astrophysics Data System (ADS)
Smarda, M.; Alexopoulou, E.; Mazioti, A.; Kordolaimi, S.; Ploussi, A.; Priftis, K.; Efstathopoulos, E.
2015-09-01
Purpose of the study is to determine the appropriate iterative reconstruction (IR) algorithm level that combines image quality and diagnostic confidence, for pediatric patients undergoing high-resolution computed tomography (HRCT). During the last 2 years, a total number of 20 children up to 10 years old with a clinical presentation of chronic bronchitis underwent HRCT in our department's 64-detector row CT scanner using the iDose IR algorithm, with almost similar image settings (80kVp, 40-50 mAs). CT images were reconstructed with all iDose levels (level 1 to 7) as well as with filtered-back projection (FBP) algorithm. Subjective image quality was evaluated by 2 experienced radiologists in terms of image noise, sharpness, contrast and diagnostic acceptability using a 5-point scale (1=excellent image, 5=non-acceptable image). Artifacts existance was also pointed out. All mean scores from both radiologists corresponded to satisfactory image quality (score ≤3), even with the FBP algorithm use. Almost excellent (score <2) overall image quality was achieved with iDose levels 5 to 7, but oversmoothing artifacts appearing with iDose levels 6 and 7 affected the diagnostic confidence. In conclusion, the use of iDose level 5 enables almost excellent image quality without considerable artifacts affecting the diagnosis. Further evaluation is needed in order to draw more precise conclusions.
NASA Astrophysics Data System (ADS)
Mickevicius, Nikolai J.; Paulson, Eric S.
2017-04-01
The purpose of this work is to investigate the effects of undersampling and reconstruction algorithm on the total processing time and image quality of respiratory phase-resolved 4D MRI data. Specifically, the goal is to obtain quality 4D-MRI data with a combined acquisition and reconstruction time of five minutes or less, which we reasoned would be satisfactory for pre-treatment 4D-MRI in online MRI-gRT. A 3D stack-of-stars, self-navigated, 4D-MRI acquisition was used to scan three healthy volunteers at three image resolutions and two scan durations. The NUFFT, CG-SENSE, SPIRiT, and XD-GRASP reconstruction algorithms were used to reconstruct each dataset on a high performance reconstruction computer. The overall image quality, reconstruction time, artifact prevalence, and motion estimates were compared. The CG-SENSE and XD-GRASP reconstructions provided superior image quality over the other algorithms. The combination of a 3D SoS sequence and parallelized reconstruction algorithms using computing hardware more advanced than those typically seen on product MRI scanners, can result in acquisition and reconstruction of high quality respiratory correlated 4D-MRI images in less than five minutes.
Rizzo, Giuseppe; Capponi, Alessandra; Pietrolucci, Maria Elena; Capece, Giuseppe; Cimmino, Ernesto; Colosi, Enrico; Ferrentino, Salvatore; Sica, Carmine; Di Meglio, Aniello; Arduini, Domenico
2011-01-01
The aim of this study was to evaluate the feasibility of visualizing standard cardiac views from 4-dimensional (4D) cardiac volumes obtained at ultrasound facilities with no specific experience in fetal echocardiography. Five sonographers prospectively recorded 4D cardiac volumes starting from the 4-chamber view on 500 consecutive pregnancies at 19 to 24 weeks' gestation undergoing routine ultrasound examinations (100 pregnancies for each sonographer). Volumes were sent to the referral center, and 2 independent reviewers with experience in 4D fetal echocardiography assessed their quality in the display of the abdominal view, 4-chamber view, left and right ventricular outflow tracts, and 3-vessel and trachea view. Cardiac volumes were acquired in 474 of 500 pregnancies (94.8%). The 2 reviewers respectively acknowledged the presence of satisfactory images in 92.4% and 93.6% of abdominal views, 91.5% and 93.0% of 4-chamber views, in 85.0% and 86.2% of left ventricular outflow tracts, 83.9% and 84.5% of right ventricular outflow tracts, and 85.2% and 84.5% of 3-vessel and trachea views. The presence of a maternal body mass index of greater than 30 altered the probability of achieving satisfactory cardiac views, whereas previous maternal lower abdominal surgery did not affect the quality of reconstructed cardiac views. In conclusion, cardiac volumes acquired by 4D sonography in peripheral centers showed high enough quality to allow satisfactory diagnostic cardiac views.
Image degradation characteristics and restoration based on regularization for diffractive imaging
NASA Astrophysics Data System (ADS)
Zhi, Xiyang; Jiang, Shikai; Zhang, Wei; Wang, Dawei; Li, Yun
2017-11-01
The diffractive membrane optical imaging system is an important development trend of ultra large aperture and lightweight space camera. However, related investigations on physics-based diffractive imaging degradation characteristics and corresponding image restoration methods are less studied. In this paper, the model of image quality degradation for the diffraction imaging system is first deduced mathematically based on diffraction theory and then the degradation characteristics are analyzed. On this basis, a novel regularization model of image restoration that contains multiple prior constraints is established. After that, the solving approach of the equation with the multi-norm coexistence and multi-regularization parameters (prior's parameters) is presented. Subsequently, the space-variant PSF image restoration method for large aperture diffractive imaging system is proposed combined with block idea of isoplanatic region. Experimentally, the proposed algorithm demonstrates its capacity to achieve multi-objective improvement including MTF enhancing, dispersion correcting, noise and artifact suppressing as well as image's detail preserving, and produce satisfactory visual quality. This can provide scientific basis for applications and possesses potential application prospects on future space applications of diffractive membrane imaging technology.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-26
... available quantities and of a satisfactory quality), with respect to Recovery Act projects funded by EERE... and of a satisfactory quality (``nonavailability''). The authority of the Secretary of Energy to make... available quantities and of a satisfactory quality. The above items, when used on eligible EERE Recovery Act...
Novel agents for sperm purification, sorting, and imaging.
Feugang, Jean M
2017-09-01
The stringent selection of viable spermatozoa ensures the transmission of high-quality genetic material to the egg during fertilization. Sperm heterogeneity within or between ejaculates and between males obliges varied post-collection handling of semen to assure satisfactory fertility rates. The current techniques used to assess sperm generally detect non-viable and non-fertilizing gametes in the ejaculate, but do not permit the investigation of semen for improved fertility outcomes. Advances in technology, however, have spurred the search for new approaches to enrich semen with high-quality spermatozoa and to track intra-uterine sperm migration. This review highlights the current and future methodologies used for sperm labeling, selection, tracking, and imaging, with specific emphasis on the recent influence of nanotechnology. © 2017 Wiley Periodicals, Inc.
Contrast-dependent saturation adjustment for outdoor image enhancement.
Wang, Shuhang; Cho, Woon; Jang, Jinbeum; Abidi, Mongi A; Paik, Joonki
2017-01-01
Outdoor images captured in bad-weather conditions usually have poor intensity contrast and color saturation since the light arriving at the camera is severely scattered or attenuated. The task of improving image quality in poor conditions remains a challenge. Existing methods of image quality improvement are usually effective for a small group of images but often fail to produce satisfactory results for a broader variety of images. In this paper, we propose an image enhancement method, which makes it applicable to enhance outdoor images by using content-adaptive contrast improvement as well as contrast-dependent saturation adjustment. The main contribution of this work is twofold: (1) we propose the content-adaptive histogram equalization based on the human visual system to improve the intensity contrast; and (2) we introduce a simple yet effective prior for adjusting the color saturation depending on the intensity contrast. The proposed method is tested with different kinds of images, compared with eight state-of-the-art methods: four enhancement methods and four haze removal methods. Experimental results show the proposed method can more effectively improve the visibility and preserve the naturalness of the images, as opposed to the compared methods.
Ali, Amir Monir
2018-01-01
The aim of the study was to evaluate the commercially available orthopedic metal artifact reduction (OMAR) technique in postoperative three-dimensional computed tomography (3DCT) reconstruction studies after spinal instrumentation and to investigate its clinical application. One hundred and twenty (120) patients with spinal metallic implants were included in the study. All had 3DCT reconstruction examinations using the OMAR software after obtaining the informed consents and approval of the Institution Ethical Committee. The degree of the artifacts, the related muscular density, the clearness of intermuscular fat planes, and definition of the adjacent vertebrae were qualitatively evaluated. The diagnostic satisfaction and quality of the 3D reconstruction images were thoroughly assessed. The majority (96.7%) of 3DCT reconstruction images performed were considered satisfactory to excellent for diagnosis. Only 3.3% of the reconstructed images had rendered unacceptable diagnostic quality. OMAR can effectively reduce metallic artifacts in patients with spinal instrumentation with highly diagnostic 3DCT reconstruction images.
Robust digital image watermarking using distortion-compensated dither modulation
NASA Astrophysics Data System (ADS)
Li, Mianjie; Yuan, Xiaochen
2018-04-01
In this paper, we propose a robust feature extraction based digital image watermarking method using Distortion- Compensated Dither Modulation (DC-DM). Our proposed local watermarking method provides stronger robustness and better flexibility than traditional global watermarking methods. We improve robustness by introducing feature extraction and DC-DM method. To extract the robust feature points, we propose a DAISY-based Robust Feature Extraction (DRFE) method by employing the DAISY descriptor and applying the entropy calculation based filtering. The experimental results show that the proposed method achieves satisfactory robustness under the premise of ensuring watermark imperceptibility quality compared to other existing methods.
Electronic magnification for astronomical camera tubes
NASA Technical Reports Server (NTRS)
Vine, J.; Hansen, J. R.; Pietrzyk, J. P.
1974-01-01
Definitions, test schemes, and analyses used to provide variable magnification in the image section of the television sensor for large space telescopes are outlined. Experimental results show a definite form of magnetic field distribution is necessary to achieve magnification in the range 3X to 4X. Coil systems to establish the required field shapes were built, and both image intensifiers and camera tubes were operated at high magnification. The experiments confirm that such operation is practical and can provide satisfactory image quality. The main problem with such a system was identified as heating of the photocathode due to concentration of coil power dissipation in that vicinity. Suggestions for overcoming this disadvantage are included.
Requirements for satisfactory flying qualities of airplanes
NASA Technical Reports Server (NTRS)
Gilruth, R R
1943-01-01
Report discusses the results of an analysis of available data to determine what measured characteristics are significant in defining satisfactory flying qualities, what characteristics are reasonable to require of an airplane, and what influence the various design features have on the observed flying qualities.
Cohen, Leeber; Mangers, Kristie; Grobman, William A; Platt, Lawrence D
2009-12-01
The purpose of this study was to determine the frequency with which 3 standard screening views of the fetal heart (4-chamber, left ventricular outflow tract [LVOT], and right ventricular outflow tract [RVOT]) can be obtained satisfactorily with the spatiotemporal image correlation (STIC) technique. A prospective study of 111 patients undergoing anatomic surveys at 18 to 22 weeks was performed. Two ultrasound machines with fetal cardiac settings were used. The best volume set that could be obtained from each patient during a 45-minute examination was graded by 2 sonologists with regard to whether the 4-chamber, LVOT, and RVOT images were satisfactory for screening. All 3 views were judged satisfactory for screening in most patients: 1 sonologist graded the views as satisfactory in 70% of the patients, whereas the other found the views to be satisfactory in 83%. The position of the placenta did not alter the probability of achieving a satisfactory view, but a fetus in the spine anterior position was associated with a significantly lower probability that the views were regarded as satisfactory for screening (odds ratio, 0.28; 95% confidence interval, 0.09-0.70; P < .05). This study suggests that STIC may assist with screening for cardiac anomalies at 18 to 22 weeks' gestation.
Sparse dictionary for synthetic transmit aperture medical ultrasound imaging.
Wang, Ping; Jiang, Jin-Yang; Li, Na; Luo, Han-Wu; Li, Fang; Cui, Shi-Gang
2017-07-01
It is possible to recover a signal below the Nyquist sampling limit using a compressive sensing technique in ultrasound imaging. However, the reconstruction enabled by common sparse transform approaches does not achieve satisfactory results. Considering the ultrasound echo signal's features of attenuation, repetition, and superposition, a sparse dictionary with the emission pulse signal is proposed. Sparse coefficients in the proposed dictionary have high sparsity. Images reconstructed with this dictionary were compared with those obtained with the three other common transforms, namely, discrete Fourier transform, discrete cosine transform, and discrete wavelet transform. The performance of the proposed dictionary was analyzed via a simulation and experimental data. The mean absolute error (MAE) was used to quantify the quality of the reconstructions. Experimental results indicate that the MAE associated with the proposed dictionary was always the smallest, the reconstruction time required was the shortest, and the lateral resolution and contrast of the reconstructed images were also the closest to the original images. The proposed sparse dictionary performed better than the other three sparse transforms. With the same sampling rate, the proposed dictionary achieved excellent reconstruction quality.
Implementation of compressive sensing for preclinical cine-MRI
NASA Astrophysics Data System (ADS)
Tan, Elliot; Yang, Ming; Ma, Lixin; Zheng, Yahong Rosa
2014-03-01
This paper presents a practical implementation of Compressive Sensing (CS) for a preclinical MRI machine to acquire randomly undersampled k-space data in cardiac function imaging applications. First, random undersampling masks were generated based on Gaussian, Cauchy, wrapped Cauchy and von Mises probability distribution functions by the inverse transform method. The best masks for undersampling ratios of 0.3, 0.4 and 0.5 were chosen for animal experimentation, and were programmed into a Bruker Avance III BioSpec 7.0T MRI system through method programming in ParaVision. Three undersampled mouse heart datasets were obtained using a fast low angle shot (FLASH) sequence, along with a control undersampled phantom dataset. ECG and respiratory gating was used to obtain high quality images. After CS reconstructions were applied to all acquired data, resulting images were quantitatively analyzed using the performance metrics of reconstruction error and Structural Similarity Index (SSIM). The comparative analysis indicated that CS reconstructed images from MRI machine undersampled data were indeed comparable to CS reconstructed images from retrospective undersampled data, and that CS techniques are practical in a preclinical setting. The implementation achieved 2 to 4 times acceleration for image acquisition and satisfactory quality of image reconstruction.
Chen, Qing; Xu, Pengfei; Liu, Wenzhong
2016-01-01
Computer vision as a fast, low-cost, noncontact, and online monitoring technology has been an important tool to inspect product quality, particularly on a large-scale assembly production line. However, the current industrial vision system is far from satisfactory in the intelligent perception of complex grain images, comprising a large number of local homogeneous fragmentations or patches without distinct foreground and background. We attempt to solve this problem based on the statistical modeling of spatial structures of grain images. We present a physical explanation in advance to indicate that the spatial structures of the complex grain images are subject to a representative Weibull distribution according to the theory of sequential fragmentation, which is well known in the continued comminution of ore grinding. To delineate the spatial structure of the grain image, we present a method of multiscale and omnidirectional Gaussian derivative filtering. Then, a product quality classifier based on sparse multikernel–least squares support vector machine is proposed to solve the low-confidence classification problem of imbalanced data distribution. The proposed method is applied on the assembly line of a food-processing enterprise to classify (or identify) automatically the production quality of rice. The experiments on the real application case, compared with the commonly used methods, illustrate the validity of our method. PMID:26986726
Real-time dynamic display of registered 4D cardiac MR and ultrasound images using a GPU
NASA Astrophysics Data System (ADS)
Zhang, Q.; Huang, X.; Eagleson, R.; Guiraudon, G.; Peters, T. M.
2007-03-01
In minimally invasive image-guided surgical interventions, different imaging modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), and real-time three-dimensional (3D) ultrasound (US), can provide complementary, multi-spectral image information. Multimodality dynamic image registration is a well-established approach that permits real-time diagnostic information to be enhanced by placing lower-quality real-time images within a high quality anatomical context. For the guidance of cardiac procedures, it would be valuable to register dynamic MRI or CT with intraoperative US. However, in practice, either the high computational cost prohibits such real-time visualization of volumetric multimodal images in a real-world medical environment, or else the resulting image quality is not satisfactory for accurate guidance during the intervention. Modern graphics processing units (GPUs) provide the programmability, parallelism and increased computational precision to begin to address this problem. In this work, we first outline our research on dynamic 3D cardiac MR and US image acquisition, real-time dual-modality registration and US tracking. Then we describe image processing and optimization techniques for 4D (3D + time) cardiac image real-time rendering. We also present our multimodality 4D medical image visualization engine, which directly runs on a GPU in real-time by exploiting the advantages of the graphics hardware. In addition, techniques such as multiple transfer functions for different imaging modalities, dynamic texture binding, advanced texture sampling and multimodality image compositing are employed to facilitate the real-time display and manipulation of the registered dual-modality dynamic 3D MR and US cardiac datasets.
Rizzo, Giuseppe; Pietrolucci, Maria Elena; Capece, Giuseppe; Cimmino, Ernesto; Colosi, Enrico; Ferrentino, Salvatore; Sica, Carmine; Di Meglio, Aniello; Arduini, Domenico
2011-08-01
The aim of this study was to evaluate the feasibility to visualize central nervous system (CNS) diagnostic planes from three-dimensional (3D) brain volumes obtained in ultrasound facilities with no specific experience in fetal neurosonography. Five sonographers prospectively recorded transabdominal 3D CNS volumes starting from an axial approach on 500 consecutive pregnancies at 19-24 weeks of gestation undergoing routine ultrasound examination. Volumes were sent to the referral center (Department of Obstetrics and Gynecology, Università Roma Tor Vergata, Italy) and two independent reviewers with experience in 3D ultrasound assessed their quality in the display of axial, coronal, and sagittal planes. CNS volumes were acquired in 491/500 pregnancies (98.2%). The two reviewers acknowledged the presence of satisfactory images with a visualization rate ranging respectively between 95.1% and 97.14% for axial planes, 73.72% and 87.16% for coronal planes, and 78.41% and 94.29% for sagittal planes. The agreement rate between the two reviewers as expressed by Cohen's kappa coefficient was >0.87 for axial planes, >0.89 for coronal planes, and >0.94 for sagittal planes. The presence of a maternal body mass index >30 alters the probability of achieving satisfactory CNS views, while existence of previous maternal lower abdomen surgery does not affect the quality of the reconstructed planes. CNS volumes acquired by 3D ultrasonography in peripheral centers showed a quality high enough to allow a detailed fetal neurosonogram.
Iterative CT reconstruction using coordinate descent with ordered subsets of data
NASA Astrophysics Data System (ADS)
Noo, F.; Hahn, K.; Schöndube, H.; Stierstorfer, K.
2016-04-01
Image reconstruction based on iterative minimization of a penalized weighted least-square criteria has become an important topic of research in X-ray computed tomography. This topic is motivated by increasing evidence that such a formalism may enable a significant reduction in dose imparted to the patient while maintaining or improving image quality. One important issue associated with this iterative image reconstruction concept is slow convergence and the associated computational effort. For this reason, there is interest in finding methods that produce approximate versions of the targeted image with a small number of iterations and an acceptable level of discrepancy. We introduce here a novel method to produce such approximations: ordered subsets in combination with iterative coordinate descent. Preliminary results demonstrate that this method can produce, within 10 iterations and using only a constant image as initial condition, satisfactory reconstructions that retain the noise properties of the targeted image.
Robust registration in case of different scaling
NASA Astrophysics Data System (ADS)
Gluhchev, Georgi J.; Shalev, Shlomo
1993-09-01
The problem of robust registration in the case of anisotropic scaling has been investigated. Registration of two images using corresponding sets of fiducial points is sensitive to inaccuracies in point placement due to poor image quality or non-rigid distortions, including possible out-of-plane rotations. An approach aimed at the detection of the most unreliable points has been developed. It is based on the a priori knowledge of the sequential ordering of rotation and scaling. A measure of guilt derived from the anomalous geometric relationships is introduced. A heuristic decision rule allowing for deletion of the most guilty points is proposed. The approach allows for more precise evaluation of the translation vector. It has been tested on phantom images with known parameters and has shown satisfactory results.
Paediatric cerebrovascular CT angiography-towards better image quality.
Thust, Stefanie C; Chong, Wui Khean Kling; Gunny, Roxana; Mazumder, Asif; Poitelea, Marius; Welsh, Anna; Ederies, Ash; Mankad, Kshitij
2014-12-01
Paediatric cerebrovascular CT angiography (CTA) can be challenging to perform due to variable cardiovascular physiology between different age groups and the risk of movement artefact. This analysis aimed to determine what proportion of CTA at our institution was of diagnostic quality and identify technical factors which could be improved. a retrospective analysis of 20 cases was performed at a national paediatric neurovascular centre assessing image quality with a subjective scoring system and Hounsfield Unit (HU) measurements. Demographic data, contrast dose, flow rate and triggering times were recorded for each patient. Using a qualitative scoring system, 75% of studies were found to be of diagnostic quality (n=9 'good', n=6 'satisfactory') and 25% (n=5) were 'poor'. Those judged subjectively to be poor had arterial contrast density measured at less than 250 HU. Increased arterial opacification was achieved for cases performed with an increased flow rate (2.5-4 mL/s) and higher intravenous contrast dose (2 mL/kg). Triggering was found to be well timed in nine cases, early in four cases and late in seven cases. Of the scans triggered early, 75% were poor. Of the scans triggered late, less (29%) were poor. High flow rates (>2.5 mL/s) were a key factor for achieving high quality paediatric cerebrovascular CTA imaging. However, appropriate triggering by starting the scan immediately on contrast opacification of the monitoring vessel plays an important role and could maintain image quality when flow rates were lower. Early triggering appeared more detrimental than late.
Han, Haihong; Li, Ning; Li, Yepeng; Fu, Ping; Yu, Dongmin; Li Zhigang; Du, Chunming; Guo, Yunchang
2015-01-01
To test the aerobic plate count examining capability of microbiology laboratories, to ensure the accuracy and comparability of quantitative bacteria examination results, and to improve the quality of monitoring. The 4 different concentration aerobic plate count piece samples were prepared and noted as I, II, III and IV. After homogeneity and stability tests, the samples were delivered to monitoring institutions. The results of I, II, III samples were logarithmic transformed, and evaluated with Z-score method using the robust average and standard deviation. The results of IV samples were evaluated as "satisfactory" when reported as < 10 CFU/piece or as "not satisfactory" otherwise. Pearson χ2 test was used to analyze the ratio results. 309 monitoring institutions, which was 99.04% of the total number, reported their results. 271 institutions reported a satisfactory result, and the satisfactory rate was 87.70%. There was no statistical difference in satisfactory rates of I, II and III samples which were 81.52%, 88.30% and 91.40% respectively. The satisfactory rate of IV samples was 93.33%. There was no statistical difference in satisfactory rates between provincial and municipal CDC. The quality control program has provided scientific data that the aerobic plate count capability of the laboratories meets the requirements of monitoring tasks.
Yang, Pengfei; Niu, Kai; Wu, Yijing; Struffert, Tobias; Dorfler, Arnd; Schafer, Sebastian; Royalty, Kevin; Strother, Charles; Chen, Guang-Hong
2015-12-01
Multimodal imaging using cone beam C-arm computed tomography (CT) may shorten the delay from ictus to revascularization for acute ischemic stroke patients with a large vessel occlusion. Largely because of limited temporal resolution, reconstruction of time-resolved CT angiography (CTA) from these systems has not yielded satisfactory results. We evaluated the image quality and diagnostic value of time-resolved C-arm CTA reconstructed using novel image processing algorithms. Studies were done under an Institutional Review Board approved protocol. Postprocessing of data from 21 C-arm CT dynamic perfusion acquisitions from 17 patients with acute ischemic stroke were done to derive time-resolved C-arm CTA images. Two observers independently evaluated image quality and diagnostic content for each case. ICC and receiver-operating characteristic analysis were performed to evaluate interobserver agreement and diagnostic value of this novel imaging modality. Time-resolved C-arm CTA images were successfully generated from 20 data sets (95.2%, 20/21). Two observers agreed well that the image quality for large cerebral arteries was good but was more limited for small cerebral arteries (distal to M1, A1, and P1). receiver-operating characteristic curves demonstrated excellent diagnostic value for detecting large vessel occlusions (area under the curve=0.987-1). Time-resolved CTAs derived from C-arm CT perfusion acquisitions provide high quality images that allowed accurate diagnosis of large vessel occlusions. Although image quality of smaller arteries in this study was not optimal ongoing modifications of the postprocessing algorithm will likely remove this limitation. Adding time-resolved C-arm CTAs to the capabilities of the angiography suite further enhances its suitability as a one-stop shop for care for patients with acute ischemic stroke. © 2015 American Heart Association, Inc.
Color extended visual cryptography using error diffusion.
Kang, InKoo; Arce, Gonzalo R; Lee, Heung-Kyu
2011-01-01
Color visual cryptography (VC) encrypts a color secret message into n color halftone image shares. Previous methods in the literature show good results for black and white or gray scale VC schemes, however, they are not sufficient to be applied directly to color shares due to different color structures. Some methods for color visual cryptography are not satisfactory in terms of producing either meaningless shares or meaningful shares with low visual quality, leading to suspicion of encryption. This paper introduces the concept of visual information pixel (VIP) synchronization and error diffusion to attain a color visual cryptography encryption method that produces meaningful color shares with high visual quality. VIP synchronization retains the positions of pixels carrying visual information of original images throughout the color channels and error diffusion generates shares pleasant to human eyes. Comparisons with previous approaches show the superior performance of the new method.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Watanabe, T.; Momose, T.; Oku, S.
It is essential to obtain realistic brain surface images, in which sulci and gyri are easily recognized, when examining the correlation between functional (PET or SPECT) and anatomical (MRI) brain studies. The volume rendering technique (VRT) is commonly employed to make three-dimensional (3D) brain surface images. This technique, however, takes considerable time to make only one 3D image. Therefore it has not been practical to make the brain surface images in arbitrary directions on a real-time basis using ordinary work stations or personal computers. The surface rendering technique (SRT), on the other hand, is much less computationally demanding, but themore » quality of resulting images is not satisfactory for our purpose. A new computer algorithm has been developed to make 3D brain surface MR images very quickly using a volume-surface rendering technique (VSRT), in which the quality of resulting images is comparable to that of VRT and computation time to SRT. In VSRT the process of volume rendering is done only once to the direction of the normal vector of each surface point, rather than each time a new view point is determined as in VRT. Subsequent reconstruction of the 3D image uses a similar algorithm to that of SRT. Thus we can obtain brain surface MR images of sufficient quality viewed from any direction on a real-time basis using an easily available personal computer (Macintosh Quadra 800). The calculation time to make a 3D image is less than 1 sec. in VSRT, while that is more than 15 sec. in the conventional VRT. The difference of resulting image quality between VSRT and VRT is almost imperceptible. In conclusion, our new technique for real-time reconstruction of 3D brain surface MR image is very useful and practical in the functional and anatomical correlation study.« less
Shimizu, Shuji; Ohtsuka, Takao; Takahata, Shunichi; Nagai, Eishi; Nakashima, Naoki; Tanaka, Masao
2016-01-01
Live demonstration of endoscopy is one of the most attractive and useful methods for education and is often organized locally in hospitals. However, problems have been apparent in terms of cost, preparation, and potential risks to patients. Our aim was to evaluate a new approach to live endoscopy whereby remote hospitals are connected by the Internet for live endoscopic demonstrations. Live endoscopy was transmitted to the Congress of the Japan Gastroenterological Endoscopic Society by 13 domestic and international hospitals. Patients with upper and lower gastrointestinal diseases and with pancreatobiliary disorders were the subjects of a live demonstration. Questionnaires were distributed to the audience and were sent to the demonstrators. Questions concerned the quality of transmitted images and sound, cost, preparations, programs, preference of style, and adverse events. Of the audience, 91.2% (249/273) answered favorably regarding the transmitted image quality and 93.8% (259/276) regarding the sound quality. All demonstrators answered favorably regarding image quality and 93% (13/14) regarding sound quality. Preparations were completed without any outsourcing at 11 sites (79%) and were evaluated as 'very easy' or 'easy' at all but one site (92.3%). Preparation cost was judged as 'very cheap' or 'cheap' at 12 sites (86%). Live endoscopy connecting multiple international centers was satisfactory in image and sound quality for both audience and demonstrators, with easy and inexpensive preparation. The remote transmission of live endoscopy from demonstrators' own hospitals was preferred to the conventional style of locally organized live endoscopy. © 2015 The Authors Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.
Combined multi-spectrum and orthogonal Laplacianfaces for fast CB-XLCT imaging with single-view data
NASA Astrophysics Data System (ADS)
Zhang, Haibo; Geng, Guohua; Chen, Yanrong; Qu, Xuan; Zhao, Fengjun; Hou, Yuqing; Yi, Huangjian; He, Xiaowei
2017-12-01
Cone-beam X-ray luminescence computed tomography (CB-XLCT) is an attractive hybrid imaging modality, which has the potential of monitoring the metabolic processes of nanophosphors-based drugs in vivo. Single-view data reconstruction as a key issue of CB-XLCT imaging promotes the effective study of dynamic XLCT imaging. However, it suffers from serious ill-posedness in the inverse problem. In this paper, a multi-spectrum strategy is adopted to relieve the ill-posedness of reconstruction. The strategy is based on the third-order simplified spherical harmonic approximation model. Then, an orthogonal Laplacianfaces-based method is proposed to reduce the large computational burden without degrading the imaging quality. Both simulated data and in vivo experimental data were used to evaluate the efficiency and robustness of the proposed method. The results are satisfactory in terms of both location and quantitative recovering with computational efficiency, indicating that the proposed method is practical and promising for single-view CB-XLCT imaging.
NASA Astrophysics Data System (ADS)
Badshah, Amir; Choudhry, Aadil Jaleel; Ullah, Shan
2017-03-01
Industries are moving towards automation in order to increase productivity and ensure quality. Variety of electronic and electromagnetic systems are being employed to assist human operator in fast and accurate quality inspection of products. Majority of these systems are equipped with cameras and rely on diverse image processing algorithms. Information is lost in 2D image, therefore acquiring accurate 3D data from 2D images is an open issue. FAST, SURF and SIFT are well-known spatial domain techniques for features extraction and henceforth image registration to find correspondence between images. The efficiency of these methods is measured in terms of the number of perfect matches found. A novel fast and robust technique for stereo-image processing is proposed. It is based on non-rigid registration using modified normalized phase correlation. The proposed method registers two images in hierarchical fashion using quad-tree structure. The registration process works through global to local level resulting in robust matches even in presence of blur and noise. The computed matches can further be utilized to determine disparity and depth for industrial product inspection. The same can be used in driver assistance systems. The preliminary tests on Middlebury dataset produced satisfactory results. The execution time for a 413 x 370 stereo-pair is 500ms approximately on a low cost DSP.
Embedding intensity image into a binary hologram with strong noise resistant capability
NASA Astrophysics Data System (ADS)
Zhuang, Zhaoyong; Jiao, Shuming; Zou, Wenbin; Li, Xia
2017-11-01
A digital hologram can be employed as a host image for image watermarking applications to protect information security. Past research demonstrates that a gray level intensity image can be embedded into a binary Fresnel hologram by error diffusion method or bit truncation coding method. However, the fidelity of the retrieved watermark image from binary hologram is generally not satisfactory, especially when the binary hologram is contaminated with noise. To address this problem, we propose a JPEG-BCH encoding method in this paper. First, we employ the JPEG standard to compress the intensity image into a binary bit stream. Next, we encode the binary bit stream with BCH code to obtain error correction capability. Finally, the JPEG-BCH code is embedded into the binary hologram. By this way, the intensity image can be retrieved with high fidelity by a BCH-JPEG decoder even if the binary hologram suffers from serious noise contamination. Numerical simulation results show that the image quality of retrieved intensity image with our proposed method is superior to the state-of-the-art work reported.
E-learning in radiology: an Italian multicentre experience.
Carriero, A; Bonomo, L; Calliada, F; Campioni, P; Colosimo, C; Cotroneo, A; Cova, M; Ettorre, G C; Fugazzola, C; Garlaschi, G; Macarini, L; Mascalchi, M; Meloni, G B; Midiri, M; Mucelli, R Pozzi; Rossi, C; Sironi, S; Torricelli, P; Beomonte, B Zobel; Zompatori, M; Zuiani, C
2012-12-01
The aim of this study was to design, deliver and evaluate an e-learning teaching programme for post-graduate radiodiagnostics training that would involve various post-graduate schools throughout Italy. All of the Directors of Italian post-graduate schools of radiodiagnostics were sent an e-mail on 27 September 2010 informing them of our willingness to set up an e-learning project for the academic year 2010-2011 in the form of single-subject teaching seminars. The proposed subjects were the semeiotics of the various organs and apparatuses in the context of "Urgent/Emergency Pathology". After having received registrations, a calendar of lessons was planned to be held between 10 November 2010 and 12 October 2011. The validity of the project was tested by means of a multiple-choice questionnaire covering the technical and didactic quality of the entire project, to be completed by the students. Fifty-one percent of the universities in Italy participated in the project: Trieste, Udine, Verona, Milan-Bicocca, Novara, Varese, Genoa, Sassari, Rome Campus, the Catholic University of Rome, Chieti, Foggia, Catania, Modena, Florence, Palermo, Bologna, Pavia, Parma and Ferrara. The lessons were attended by a total of 10,261 post-graduate medical students, for an average of 513.1 students per lesson. Seventy percent of the students judged the didactic content "excellent", 25% "good", and 5% "satisfactory"; none said it was unsatisfactory. In terms of visual quality (particularly the details of the radiological images proposed in the form of slides and/or video clips), 73% judged it "excellent", 20% "good", 6% "satisfactory", and 1% "poor". The audio quality was judged "excellent" by 71%, "good" by 22%, "satisfactory" by 6% and "poor" by 1%. In relation to judgement of audio and video quality, it has to be underlined that this was greatly affected by the hardware/software configuration and the band speed and technology of the Internet connection. Technological evolution is overcoming all barriers, and technology is also having a positive impact on the approach to teaching. Our multicentre teaching experience merits the following considerations: the quality of the teaching product was certified by the students' judgements of its didactic content and the quality of reception; the economic cost of the teaching had a minimal impact on the post-graduate schools (€ 18 per lesson). In terms of breaking down national barriers, it is to be hoped that the coordination and integration of diagnostic imaging e-learning projects, with the participation of post-graduate schools in different European countries, can be developed not only in a spirit of "cultural sharing" and the exchange of teaching experiences. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Valous, Nektarios A; Mendoza, Fernando; Sun, Da-Wen; Allen, Paul
2010-03-01
The quaternionic singular value decomposition is a technique to decompose a quaternion matrix (representation of a colour image) into quaternion singular vector and singular value component matrices exposing useful properties. The objective of this study was to use a small portion of uncorrelated singular values, as robust features for the classification of sliced pork ham images, using a supervised artificial neural network classifier. Images were acquired from four qualities of sliced cooked pork ham typically consumed in Ireland (90 slices per quality), having similar appearances. Mahalanobis distances and Pearson product moment correlations were used for feature selection. Six highly discriminating features were used as input to train the neural network. An adaptive feedforward multilayer perceptron classifier was employed to obtain a suitable mapping from the input dataset. The overall correct classification performance for the training, validation and test set were 90.3%, 94.4%, and 86.1%, respectively. The results confirm that the classification performance was satisfactory. Extracting the most informative features led to the recognition of a set of different but visually quite similar textural patterns based on quaternionic singular values. Copyright 2009 Elsevier Ltd. All rights reserved.
Local ROI Reconstruction via Generalized FBP and BPF Algorithms along More Flexible Curves.
Yu, Hengyong; Ye, Yangbo; Zhao, Shiying; Wang, Ge
2006-01-01
We study the local region-of-interest (ROI) reconstruction problem, also referred to as the local CT problem. Our scheme includes two steps: (a) the local truncated normal-dose projections are extended to global dataset by combining a few global low-dose projections; (b) the ROI are reconstructed by either the generalized filtered backprojection (FBP) or backprojection-filtration (BPF) algorithms. The simulation results show that both the FBP and BPF algorithms can reconstruct satisfactory results with image quality in the ROI comparable to that of the corresponding global CT reconstruction.
Image labeling. The need for a better look.
Hunter, T
1994-10-01
The important message in this editorial is for radiologists to critically examine how well images are labeled in their own department. If it is not satisfactory, then institute corrective measures. These can range from sophisticated computer programs for printing flashcards to merely sending the chief technologist all those films one comes across with unreadable labels. The quality of the image labeling should also be a consideration when purchasing CT, MRI, ultrasound, computed radiography and digital angiography equipment. The fact that you consider this important should be communicated to equipment manufacturers in the hope that they will pay more attention to it and offer more flexibility for each department to design its own labels. In any event, I feel consistently bad film labeling results in sloppy radiology with possible patient harm and unpleasant legal consequences for the radiologist.
Acceptance testing and commissioning of Kodak Directview CR-850 digital radiography system.
Bezak, E; Nelligan, R A
2006-03-01
This Technical Paper describes Acceptance Testing and Commissioning of the Kodak DirectView CR-850 digital radiography system installed at the Royal Adelaide Hospital. The first of its type installed in Australia, the system is a "dry" image processor, for which no chemicals are required to develop images. Rather, latent radiographic images are stored on photostimulable phosphor screens, which are scanned and displayed by a reader unit. The image can be digitally processed and enhanced before it is forwarded to a storage device, printer or workstation display, thereby alleviating the need to re-expose patients to achieve satisfactory quality images. The phosphor screens are automatically erased, ready for re-use. Results are reported of tests carried out using the optional "Total Quality Tool" quality assurance package installed with the system. This package includes analysis and reporting software which provides for simple testing and reporting of many important characteristics of the system, such as field uniformity, aspect ratio, line and pixel positions, image and system noise, exposure response, scan linearity, modulation transfer function (MTF) and image artefacts. Acceptance Tests were performed for kV and MV exposures. Resolution for MV exposures was at least 0.8 l/mm, and measured phantom dimensions were within 1.05% of expected magnification. Reproducibility between cassettes was within 1.6%. The mean pixel values on the central axis were close to linear for MV exposures from 3 to 10 MU and reached saturation level at around 20 MU for 6 MV and around 30 MV for 23 MV beams. Noise levels were below 0.2 %.
Assessment of liver ablation using cone beam computed tomography.
Abdel-Rehim, Mohamed; Ronot, Maxime; Sibert, Annie; Vilgrain, Valérie
2015-01-14
To investigate the feasibility and accuracy of cone beam computed tomography (CBCT) in assessing the ablation zone after liver tumor ablation. Twenty-three patients (17 men and 6 women, range: 45-85 years old, mean age 65 years) with malignant liver tumors underwent ultrasound-guided percutaneous tumor ablation [radiofrequency (n = 14), microwave (n = 9)] followed by intravenous contrast-enhanced CBCT. Baseline multidetector computed tomography (MDCT) and peri-procedural CBCT images were compared. CBCT image quality was assessed as poor, good, or excellent. Image fusion was performed to assess tumor coverage, and quality of fusion was rated as bad, good, or excellent. Ablation zone volumes on peri-procedural CBCT and post-procedural MDCT were compared using the non-parametric paired Wilcoxon t-test. Rate of primary ablation effectiveness was 100%. There were no complications related to ablation. Local tumor recurrence and new liver tumors were found 3 mo after initial treatment in one patient (4%). The ablation zone was identified in 21/23 (91.3%) patients on CBCT. The fusion of baseline MDCT and peri-procedural CBCT images was feasible in all patients and showed satisfactory tumor coverage (at least 5-mm margin). CBCT image quality was poor, good, and excellent in 2 (9%), 8 (35%), and 13 (56%), patients respectively. Registration quality between peri-procedural CBCT and post-procedural MDCT images was good to excellent in 17/23 (74%) patients. The median ablation volume on peri-procedural CBCT and post-procedural MDCT was 30 cm(3) (range: 4-95 cm(3)) and 30 cm(3) (range: 4-124 cm(3)), respectively (P-value > 0.2). There was a good correlation (r = 0.79) between the volumes of the two techniques. Contrast-enhanced CBCT after tumor ablation of the liver allows early assessment of the ablation zone.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-29
... States in sufficient and reasonably available quantities and of a satisfactory quality), with respect to... hour lamp life; (2) Ancillary items needed for a T-12 to T-8 retrofit, including the ballast... quantities and of a satisfactory quality (``nonavailability''). The authority of the Secretary of Energy to...
Snapshot gradient-recalled echo-planar images of rat brains at long echo time at 9.4 T
Lei, Hongxia; Mlynárik, Vladimir; Just, Nathalie; Gruetter, Rolf
2009-01-01
With improved B0 homogeneity along with satisfactory gradient performance at high magnetic fields, snapshot gradient-recalled echo-planar imaging (GRE-EPI) would perform at long echo times (TEs) on the order of T2*, which intrinsically allows obtaining strongly T2*-weighted images with embedded substantial anatomical details in ultrashort time. The aim of this study was to investigate the feasibility and quality of long TE snapshot GRE-EPI images of rat brain at 9.4 T. When compensating for B0 inhomogeneities, especially second-order shim terms, a 200×200 μm2 in-plane resolution image was reproducibly obtained at long TE (>25 ms). The resulting coronal images at 30 ms had diminished geometric distortions and, thus, embedded substantial anatomical details. Concurrently with the very consistent stability, such GRE-EPI images should permit to resolve functional data not only with high specificity but also with substantial anatomical details, therefore allowing coregistration of the acquired functional data on the same image data set. PMID:18486393
Colony image acquisition and segmentation
NASA Astrophysics Data System (ADS)
Wang, W. X.
2007-12-01
For counting of both colonies and plaques, there is a large number of applications including food, dairy, beverages, hygiene, environmental monitoring, water, toxicology, sterility testing, AMES testing, pharmaceuticals, paints, sterile fluids and fungal contamination. Recently, many researchers and developers have made efforts for this kind of systems. By investigation, some existing systems have some problems. The main problems are image acquisition and image segmentation. In order to acquire colony images with good quality, an illumination box was constructed as: the box includes front lightning and back lightning, which can be selected by users based on properties of colony dishes. With the illumination box, lightning can be uniform; colony dish can be put in the same place every time, which make image processing easy. The developed colony image segmentation algorithm consists of the sub-algorithms: (1) image classification; (2) image processing; and (3) colony delineation. The colony delineation algorithm main contain: the procedures based on grey level similarity, on boundary tracing, on shape information and colony excluding. In addition, a number of algorithms are developed for colony analysis. The system has been tested and satisfactory.
Degraded character recognition based on gradient pattern
NASA Astrophysics Data System (ADS)
Babu, D. R. Ramesh; Ravishankar, M.; Kumar, Manish; Wadera, Kevin; Raj, Aakash
2010-02-01
Degraded character recognition is a challenging problem in the field of Optical Character Recognition (OCR). The performance of an optical character recognition depends upon printed quality of the input documents. Many OCRs have been designed which correctly identifies the fine printed documents. But, very few reported work has been found on the recognition of the degraded documents. The efficiency of the OCRs system decreases if the input image is degraded. In this paper, a novel approach based on gradient pattern for recognizing degraded printed character is proposed. The approach makes use of gradient pattern of an individual character for recognition. Experiments were conducted on character image that is either digitally written or a degraded character extracted from historical documents and the results are found to be satisfactory.
Lu, Shukuan; Hu, Hong; Yu, Xianbo; Long, Jiangying; Jing, Bowen; Zong, Yujin; Wan, Mingxi
2018-03-01
Pulse-echo imaging technique can only play a role when high intensity focused ultrasound (HIFU) is turned off due to the interference between the primary HIFU signal and the transmission pulse. Passive acoustic mapping (PAM) has been proposed as a tool for true real-time monitoring of HIFU therapy. However, the most-used PAM algorithm based on time exposure acoustic (TEA) limits the quality of cavitation image. Recently, robust Capon beamformer (RCB) has been used in PAM to provide improved resolution and reduced artifacts over TEA-based PAM, but the presented results have not been satisfactory. In the present study, we applied an eigenspace-based RCB (EISRCB) method to further improve the PAM image quality. The optimal weighting vector of the proposed method was found by projecting the RCB weighting vector onto the desired vector subspace constructed from the eigenstructure of the covariance matrix. The performance of the proposed PAM was validated by both simulations and in vitro histotripsy experiments. The results suggested that the proposed PAM significantly outperformed the conventionally used TEA and RCB-based PAM. The comparison results between pulse-echo images of the residual bubbles and cavitation images showed the potential of our proposed PAM in accurate localization of cavitation activity during HIFU therapy. Copyright © 2017 Elsevier B.V. All rights reserved.
He, Longjun; Ming, Xing; Liu, Qian
2014-04-01
With computing capability and display size growing, the mobile device has been used as a tool to help clinicians view patient information and medical images anywhere and anytime. However, for direct interactive 3D visualization, which plays an important role in radiological diagnosis, the mobile device cannot provide a satisfactory quality of experience for radiologists. This paper developed a medical system that can get medical images from the picture archiving and communication system on the mobile device over the wireless network. In the proposed application, the mobile device got patient information and medical images through a proxy server connecting to the PACS server. Meanwhile, the proxy server integrated a range of 3D visualization techniques, including maximum intensity projection, multi-planar reconstruction and direct volume rendering, to providing shape, brightness, depth and location information generated from the original sectional images for radiologists. Furthermore, an algorithm that changes remote render parameters automatically to adapt to the network status was employed to improve the quality of experience. Finally, performance issues regarding the remote 3D visualization of the medical images over the wireless network of the proposed application were also discussed. The results demonstrated that this proposed medical application could provide a smooth interactive experience in the WLAN and 3G networks.
Experiences with the European guidelines on quality criteria for radiographic images in Tanzania
Muhogora, W. E.; Nyanda, A. M.; Kazema, R. R.
2001-01-01
Objective assessment of the quality of radiographic images is practically a difficult task and protocols that address this problem are few. In 1996, the European union published nearly objective image quality criteria to unify the practices in Europe. However, experience with these criteria in countries of lower health care levels is little documented. As a case study in Tanzania, we present the general performance of European guidelines in some Tanzanian hospitals to a total of 200 radiographs obtained from some common x‐ray examinations. The results show that more than 70% of chest (PA), lumbar spine (AP), and pelvis AP radiographs passed the quality criteria, while the performance of lumbar spine LAT x‐ray examinations was about 50% and therefore less satisfactory. The corresponding mean entrance dose to the patient for specified x‐ray techniques was of range 0.08–0.56 mGy, 3.1–7.7 mGy, 2.53–5.4 mGy, and 4.0–16.78 mGy for chest PA, lumbar spine AP, pelvis AP and lumbar spine LAT x‐ray examinations, respectively. Although a good number of observers were not well familiar to the guidelines, the quality criteria have been found useful and their adoption in the country recommended. The need to provide relevant education and training to staff in the radiology departments is of utmost importance. PACS number(s): 87.57.–s, 87.52.–g PMID:11686743
CRITICAL ANALYSIS OF ARTIFICIAL TEETH FOR ENDODONTIC TEACHING
Nassri, Maria Renata Giazzi; Carlik, Jaime; da Silva, Camila Roberta Nepomuceno; Okagawa, Renata Elisa; Lin, Suzy
2008-01-01
The purpose of this study was to evaluate the use of artificial teeth for endodontic teaching. A questionnaire was prepared and submitted to 18 professors of Endodontics from different Brazilian universities to evaluate the following features of five cloudy resin artificial teeth: internal and external anatomy; coronal chambers regarding their size, shape and canal path; root canal regarding their size, shape and position; fulfillment of the pulp chamber and root canals by considering the texture, quantity, color, and ease of handling; resin hardness and visualization of the radiographic image. The results presented favorable opinions, in terms of internal and external anatomy, coronal pulp chambers and root canal and handling and radiographic imaging. The contents of the pulp space and hardness of the teeth were considered satisfactory. The average grade assigned to the artificial tooth quality was 8.4, in a 0-10 scale. In conclusion, the artificial teeth have potential to replace the natural teeth in endodontic teaching; however, improvements are still necessary to reach a better quality model. PMID:19089288
Critical analysis of artificial teeth for endodontic teaching.
Nassri, Maria Renata Giazzi; Carlik, Jaime; da Silva, Camila Roberta Nepomuceno; Okagawa, Renata Elisa; Lin, Suzy
2008-01-01
The purpose of this study was to evaluate the use of artificial teeth for endodontic teaching. A questionnaire was prepared and submitted to 18 professors of Endodontics from different Brazilian universities to evaluate the following features of five cloudy resin artificial teeth: internal and external anatomy; coronal chambers regarding their size, shape and canal path; root canal regarding their size, shape and position; fulfillment of the pulp chamber and root canals by considering the texture, quantity, color, and ease of handling; resin hardness and visualization of the radiographic image. The results presented favorable opinions, in terms of internal and external anatomy, coronal pulp chambers and root canal and handling and radiographic imaging. The contents of the pulp space and hardness of the teeth were considered satisfactory. The average grade assigned to the artificial tooth quality was 8.4, in a 0-10 scale. In conclusion, the artificial teeth have potential to replace the natural teeth in endodontic teaching; however, improvements are still necessary to reach a better quality model.
Bai, Chen; Xu, Shanshan; Duan, Junbo; Jing, Bowen; Yang, Miao; Wan, Mingxi
2017-08-01
Pulse-inversion subharmonic (PISH) imaging can display information relating to pure cavitation bubbles while excluding that of tissue. Although plane-wave-based ultrafast active cavitation imaging (UACI) can monitor the transient activities of cavitation bubbles, its resolution and cavitation-to-tissue ratio (CTR) are barely satisfactory but can be significantly improved by introducing eigenspace-based (ESB) adaptive beamforming. PISH and UACI are a natural combination for imaging of pure cavitation activity in tissue; however, it raises two problems: 1) the ESB beamforming is hard to implement in real time due to the enormous amount of computation associated with the covariance matrix inversion and eigendecomposition and 2) the narrowband characteristic of the subharmonic filter will incur a drastic degradation in resolution. Thus, in order to jointly address these two problems, we propose a new PISH-UACI method using novel fast ESB (F-ESB) beamforming and cavitation deconvolution for nonlinear signals. This method greatly reduces the computational complexity by using F-ESB beamforming through dimensionality reduction based on principal component analysis, while maintaining the high quality of ESB beamforming. The degraded resolution is recovered using cavitation deconvolution through a modified convolution model and compressive deconvolution. Both simulations and in vitro experiments were performed to verify the effectiveness of the proposed method. Compared with the ESB-based PISH-UACI, the entire computation of our proposed approach was reduced by 99%, while the axial resolution gain and CTR were increased by 3 times and 2 dB, respectively, confirming that satisfactory performance can be obtained for monitoring pure cavitation bubbles in tissue erosion.
Privacy-Aware Image Encryption Based on Logistic Map and Data Hiding
NASA Astrophysics Data System (ADS)
Sun, Jianglin; Liao, Xiaofeng; Chen, Xin; Guo, Shangwei
The increasing need for image communication and storage has created a great necessity for securely transforming and storing images over a network. Whereas traditional image encryption algorithms usually consider the security of the whole plain image, region of interest (ROI) encryption schemes, which are of great importance in practical applications, protect the privacy regions of plain images. Existing ROI encryption schemes usually adopt approximate techniques to detect the privacy region and measure the quality of encrypted images; however, their performance is usually inconsistent with a human visual system (HVS) and is sensitive to statistical attacks. In this paper, we propose a novel privacy-aware ROI image encryption (PRIE) scheme based on logistical mapping and data hiding. The proposed scheme utilizes salient object detection to automatically, adaptively and accurately detect the privacy region of a given plain image. After private pixels have been encrypted using chaotic cryptography, the significant bits are embedded into the nonprivacy region of the plain image using data hiding. Extensive experiments are conducted to illustrate the consistency between our automatic ROI detection and HVS. Our experimental results also demonstrate that the proposed scheme exhibits satisfactory security performance.
Chalouhi, Gihad E; Salomon, Laurent J; Fontanges, Marianne; Althuser, Marc; Haddad, Georges; Scemama, Olivier; Chabot, Jean-Michel; Duyme, Michel; Fries, Nicolas
2013-09-01
The purpose of this work was to study the impact of an audit and feedback on the quality of routine first-trimester nuchal transparency ultrasound images. Eighty-eight sonographers were each sent 2 different series of 30 consecutive nuchal translucency images at a mean interval of 3 months to a dedicated, protected server for remote double-blind independent analysis based on the new Collège Français d'Echographie Foetale/Centre National de la Recherche Scientifique image-scoring method (https://www.cfef.org/evaluation/ISMCFEFCNRS.pdf). The sonographers were classified as low (score below the median) or high (score above the median) scorers for each series. Before their second evaluation, 73 of the 88 sonographers received a feedback report on their first series of images, whereas the other 15 participants received no feedback. The baseline characteristics of the participants who did and did not receive feedback were comparable. Participants who received feedback increased their average score significantly, from a mean ± SD of 11.1 ± 1.3 to 13.4 ± 1.4 among low scorers (P < .00001) and from 15.1 ± 1.2 to 16.0 ± 1.4 among high scorers (P < .001), whereas no significant change was seen among participants who received no feedback (low scorers, 10.9 ± 1.5 to 12.1 ± 2.0; P = .11; high scorers, 14.7 ± 1.3 to 14.6 ± 1.3; P = .99). The proportion of satisfactory images increased by 48% among low scorers who received feedback. Formative assessment based on a moderately intensive audit and feedback is feasible and effective for improving the quality of routine first-trimester nuchal transparency ultrasound images.
Multi-focus image fusion with the all convolutional neural network
NASA Astrophysics Data System (ADS)
Du, Chao-ben; Gao, She-sheng
2018-01-01
A decision map contains complete and clear information about the image to be fused, which is crucial to various image fusion issues, especially multi-focus image fusion. However, in order to get a satisfactory image fusion effect, getting a decision map is very necessary and usually difficult to finish. In this letter, we address this problem with convolutional neural network (CNN), aiming to get a state-of-the-art decision map. The main idea is that the max-pooling of CNN is replaced by a convolution layer, the residuals are propagated backwards by gradient descent, and the training parameters of the individual layers of the CNN are updated layer by layer. Based on this, we propose a new all CNN (ACNN)-based multi-focus image fusion method in spatial domain. We demonstrate that the decision map obtained from the ACNN is reliable and can lead to high-quality fusion results. Experimental results clearly validate that the proposed algorithm can obtain state-of-the-art fusion performance in terms of both qualitative and quantitative evaluations.
Color quality management in advanced flat panel display engines
NASA Astrophysics Data System (ADS)
Lebowsky, Fritz; Neugebauer, Charles F.; Marnatti, David M.
2003-01-01
During recent years color reproduction systems for consumer needs have experienced various difficulties. In particular, flat panels and printers could not reach a satisfactory color match. The RGB image stored on an Internet server of a retailer did not show the desired colors on a consumer display device or printer device. STMicroelectronics addresses this important color reproduction issue inside their advanced display engines using novel algorithms targeted for low cost consumer flat panels. Using a new and genuine RGB color space transformation, which combines a gamma correction Look-Up-Table, tetrahedrization, and linear interpolation, we satisfy market demands.
Local ROI Reconstruction via Generalized FBP and BPF Algorithms along More Flexible Curves
Ye, Yangbo; Zhao, Shiying; Wang, Ge
2006-01-01
We study the local region-of-interest (ROI) reconstruction problem, also referred to as the local CT problem. Our scheme includes two steps: (a) the local truncated normal-dose projections are extended to global dataset by combining a few global low-dose projections; (b) the ROI are reconstructed by either the generalized filtered backprojection (FBP) or backprojection-filtration (BPF) algorithms. The simulation results show that both the FBP and BPF algorithms can reconstruct satisfactory results with image quality in the ROI comparable to that of the corresponding global CT reconstruction. PMID:23165018
Nonlinear Fusion of Multispectral Citrus Fruit Image Data with Information Contents.
Li, Peilin; Lee, Sang-Heon; Hsu, Hung-Yao; Park, Jae-Sam
2017-01-13
The main issue of vison-based automatic harvesting manipulators is the difficulty in the correct fruit identification in the images under natural lighting conditions. Mostly, the solution has been based on a linear combination of color components in the multispectral images. However, the results have not reached a satisfactory level. To overcome this issue, this paper proposes a robust nonlinear fusion method to augment the original color image with the synchronized near infrared image. The two images are fused with Daubechies wavelet transform (DWT) in a multiscale decomposition approach. With DWT, the background noises are reduced and the necessary image features are enhanced by fusing the color contrast of the color components and the homogeneity of the near infrared (NIR) component. The resulting fused color image is classified with a C-means algorithm for reconstruction. The performance of the proposed approach is evaluated with the statistical F measure in comparison to some existing methods using linear combinations of color components. The results show that the fusion of information in different spectral components has the advantage of enhancing the image quality, therefore improving the classification accuracy in citrus fruit identification in natural lighting conditions.
Nonlinear Fusion of Multispectral Citrus Fruit Image Data with Information Contents
Li, Peilin; Lee, Sang-Heon; Hsu, Hung-Yao; Park, Jae-Sam
2017-01-01
The main issue of vison-based automatic harvesting manipulators is the difficulty in the correct fruit identification in the images under natural lighting conditions. Mostly, the solution has been based on a linear combination of color components in the multispectral images. However, the results have not reached a satisfactory level. To overcome this issue, this paper proposes a robust nonlinear fusion method to augment the original color image with the synchronized near infrared image. The two images are fused with Daubechies wavelet transform (DWT) in a multiscale decomposition approach. With DWT, the background noises are reduced and the necessary image features are enhanced by fusing the color contrast of the color components and the homogeneity of the near infrared (NIR) component. The resulting fused color image is classified with a C-means algorithm for reconstruction. The performance of the proposed approach is evaluated with the statistical F measure in comparison to some existing methods using linear combinations of color components. The results show that the fusion of information in different spectral components has the advantage of enhancing the image quality, therefore improving the classification accuracy in citrus fruit identification in natural lighting conditions. PMID:28098797
Comparison Study of Regularizations in Spectral Computed Tomography Reconstruction
NASA Astrophysics Data System (ADS)
Salehjahromi, Morteza; Zhang, Yanbo; Yu, Hengyong
2018-12-01
The energy-resolving photon-counting detectors in spectral computed tomography (CT) can acquire projections of an object in different energy channels. In other words, they are able to reliably distinguish the received photon energies. These detectors lead to the emerging spectral CT, which is also called multi-energy CT, energy-selective CT, color CT, etc. Spectral CT can provide additional information in comparison with the conventional CT in which energy integrating detectors are used to acquire polychromatic projections of an object being investigated. The measurements obtained by X-ray CT detectors are noisy in reality, especially in spectral CT where the photon number is low in each energy channel. Therefore, some regularization should be applied to obtain a better image quality for this ill-posed problem in spectral CT image reconstruction. Quadratic-based regularizations are not often satisfactory as they blur the edges in the reconstructed images. As a result, different edge-preserving regularization methods have been adopted for reconstructing high quality images in the last decade. In this work, we numerically evaluate the performance of different regularizers in spectral CT, including total variation, non-local means and anisotropic diffusion. The goal is to provide some practical guidance to accurately reconstruct the attenuation distribution in each energy channel of the spectral CT data.
Ten-year experience of remote medical education in Asia.
Shimizu, Shuji; Kudo, Kuriko; Antoku, Yasuaki; Hu, Min; Okamura, Koji; Nakashima, Naoki
2014-11-01
Moving images are often essential in medical education, to learn new procedures and advanced skills, but, in the past, high-quality movie transmission was technically much more challenging than transmitting still pictures because of technological limitations and cost. We established a new system, taking advantage of two advanced technologies, the digital video transport system (DVTS) and the research and education network (REN), which enabled satisfactory telemedicine on a routine basis. Between 2003 and 2013, we organized 360 programs connecting 221 hospitals or facilities in 34 countries in Asia and beyond. The two main areas were endoscopy and surgery, with 113 (31%) and 106 (29%) events, respectively. Teleconferences made up 76% of the total events, with the remaining 24% being live demonstrations. Multiple connections were more popular (63%) than one-to-one connections (37%). With continuous technological development, new high-definition H.323 and Vidyo(®) (Hackensack, NJ) systems were used in 47% and 39% of events in 2011 and 2012, respectively. The evaluation by questionnaires was favorable on image and sound quality as well as programs. Remote medical education with moving images was well accepted in Asia with changing needs and developing technologies.
Ten-Year Experience of Remote Medical Education in Asia
Kudo, Kuriko; Antoku, Yasuaki; Hu, Min; Okamura, Koji; Nakashima, Naoki
2014-01-01
Abstract Background: Moving images are often essential in medical education, to learn new procedures and advanced skills, but, in the past, high-quality movie transmission was technically much more challenging than transmitting still pictures because of technological limitations and cost. Materials and Methods: We established a new system, taking advantage of two advanced technologies, the digital video transport system (DVTS) and the research and education network (REN), which enabled satisfactory telemedicine on a routine basis. Results: Between 2003 and 2013, we organized 360 programs connecting 221 hospitals or facilities in 34 countries in Asia and beyond. The two main areas were endoscopy and surgery, with 113 (31%) and 106 (29%) events, respectively. Teleconferences made up 76% of the total events, with the remaining 24% being live demonstrations. Multiple connections were more popular (63%) than one-to-one connections (37%). With continuous technological development, new high-definition H.323 and Vidyo® (Hackensack, NJ) systems were used in 47% and 39% of events in 2011 and 2012, respectively. The evaluation by questionnaires was favorable on image and sound quality as well as programs. Conclusions: Remote medical education with moving images was well accepted in Asia with changing needs and developing technologies. PMID:25272006
Job-shop scheduling applied to computer vision
NASA Astrophysics Data System (ADS)
Sebastian y Zuniga, Jose M.; Torres-Medina, Fernando; Aracil, Rafael; Reinoso, Oscar; Jimenez, Luis M.; Garcia, David
1997-09-01
This paper presents a method for minimizing the total elapsed time spent by n tasks running on m differents processors working in parallel. The developed algorithm not only minimizes the total elapsed time but also reduces the idle time and waiting time of in-process tasks. This condition is very important in some applications of computer vision in which the time to finish the total process is particularly critical -- quality control in industrial inspection, real- time computer vision, guided robots. The scheduling algorithm is based on the use of two matrices, obtained from the precedence relationships between tasks, and the data obtained from the two matrices. The developed scheduling algorithm has been tested in one application of quality control using computer vision. The results obtained have been satisfactory in the application of different image processing algorithms.
Xiao, Xia; Feng, Ya-Ping; Du, Bin; Sun, Han-Ru; Ding, You-Quan; Qi, Jian-Guo
2017-03-01
Fluorescent immunolabeling and imaging in free-floating thick (50-60 μm) tissue sections is relatively simple in practice and enables design-based non-biased stereology, or 3-D reconstruction and analysis. This method is widely used for 3-D in situ quantitative biology in many areas of biological research. However, the labeling quality and efficiency of standard protocols for fluorescent immunolabeling of these tissue sections are not always satisfactory. Here, we systematically evaluate the effects of raising the conventional antibody incubation temperatures (4°C or 21°C) to mammalian body temperature (37°C) in these protocols. Our modification significantly enhances the quality (labeling sensitivity, specificity, and homogeneity) and efficiency (antibody concentration and antibody incubation duration) of fluorescent immunolabeling of free-floating thick tissue sections.
Imaging in syndesmotic injury: a systematic literature review.
Krähenbühl, Nicola; Weinberg, Maxwell W; Davidson, Nathan P; Mills, Megan K; Hintermann, Beat; Saltzman, Charles L; Barg, Alexej
2018-05-01
To give a systematic overview of current diagnostic imaging options for assessment of the distal tibio-fibular syndesmosis. A systematic literature search across the following sources was performed: PubMed, ScienceDirect, Google Scholar, and SpringerLink. Forty-two articles were included and subdivided into three groups: group one consists of studies using conventional radiographs (22 articles), group two includes studies using computed tomography (CT) scans (15 articles), and group three comprises studies using magnet resonance imaging (MRI, 9 articles).The following data were extracted: imaging modality, measurement method, number of participants and ankles included, average age of participants, sensitivity, specificity, and accuracy of the measurement technique. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was used to assess the methodological quality. The three most common techniques used for assessment of the syndesmosis in conventional radiographs are the tibio-fibular clear space (TFCS), the tibio-fibular overlap (TFO), and the medial clear space (MCS). Regarding CT scans, the tibio-fibular width (axial images) was most commonly used. Most of the MRI studies used direct assessment of syndesmotic integrity. Overall, the included studies show low probability of bias and are applicable in daily practice. Conventional radiographs cannot predict syndesmotic injuries reliably. CT scans outperform plain radiographs in detecting syndesmotic mal-reduction. Additionally, the syndesmotic interval can be assessed in greater detail by CT. MRI measurements achieve a sensitivity and specificity of nearly 100%; however, correlating MRI findings with patients' complaints is difficult, and utility with subtle syndesmotic instability needs further investigation. Overall, the methodological quality of these studies was satisfactory.
Yuan, Jie; Xu, Guan; Yu, Yao; Zhou, Yu; Carson, Paul L; Wang, Xueding; Liu, Xiaojun
2013-08-01
Photoacoustic tomography (PAT) offers structural and functional imaging of living biological tissue with highly sensitive optical absorption contrast and excellent spatial resolution comparable to medical ultrasound (US) imaging. We report the development of a fully integrated PAT and US dual-modality imaging system, which performs signal scanning, image reconstruction, and display for both photoacoustic (PA) and US imaging all in a truly real-time manner. The back-projection (BP) algorithm for PA image reconstruction is optimized to reduce the computational cost and facilitate parallel computation on a state of the art graphics processing unit (GPU) card. For the first time, PAT and US imaging of the same object can be conducted simultaneously and continuously, at a real-time frame rate, presently limited by the laser repetition rate of 10 Hz. Noninvasive PAT and US imaging of human peripheral joints in vivo were achieved, demonstrating the satisfactory image quality realized with this system. Another experiment, simultaneous PAT and US imaging of contrast agent flowing through an artificial vessel, was conducted to verify the performance of this system for imaging fast biological events. The GPU-based image reconstruction software code for this dual-modality system is open source and available for download from http://sourceforge.net/projects/patrealtime.
Multi-viewpoint Image Array Virtual Viewpoint Rapid Generation Algorithm Based on Image Layering
NASA Astrophysics Data System (ADS)
Jiang, Lu; Piao, Yan
2018-04-01
The use of multi-view image array combined with virtual viewpoint generation technology to record 3D scene information in large scenes has become one of the key technologies for the development of integrated imaging. This paper presents a virtual viewpoint rendering method based on image layering algorithm. Firstly, the depth information of reference viewpoint image is quickly obtained. During this process, SAD is chosen as the similarity measure function. Then layer the reference image and calculate the parallax based on the depth information. Through the relative distance between the virtual viewpoint and the reference viewpoint, the image layers are weighted and panned. Finally the virtual viewpoint image is rendered layer by layer according to the distance between the image layers and the viewer. This method avoids the disadvantages of the algorithm DIBR, such as high-precision requirements of depth map and complex mapping operations. Experiments show that, this algorithm can achieve the synthesis of virtual viewpoints in any position within 2×2 viewpoints range, and the rendering speed is also very impressive. The average result proved that this method can get satisfactory image quality. The average SSIM value of the results relative to real viewpoint images can reaches 0.9525, the PSNR value can reaches 38.353 and the image histogram similarity can reaches 93.77%.
NASA Astrophysics Data System (ADS)
Wang, Xuan-Yin; Du, Jia-Wei; Zhu, Shi-Qiang
2017-09-01
A bionic variable-focus lens with symmetrical layered structure was designed to mimic the crystalline lens. An optical imaging system based on this lens and with a symmetrical structure that mimics the human eye structure was proposed. The refractive index of the bionic variable-focus lens increases from outside to inside. The two PDMS lenses with a certain thickness were designed to improve the optical performance of the optical imaging system and minimise the gravity effect of liquid. The paper presents the overall structure of the optical imaging system and the detailed description of the bionic variable-focus lens. By pumping liquid in or out of the cavity, the surface curvatures of the rear PDMS lens were varied, resulting in a change in the focal length. The focal length range of the optical imaging system was 20.71-24.87 mm. The optical performance of the optical imaging system was evaluated by imaging experiments and analysed by ray tracing simulations. On the basis of test and simulation results, the optical performance of the system was quite satisfactory. Off-axis aberrations were well corrected, and the image quality was greatly improved.
Barth, Albert D; Waldner, Cheryl L
2002-04-01
Breeding soundness evaluation records from 2110 beef bulls, for the period of 1986 to 1999, were analyzed to determine the prevalence and importance of factors affecting breeding soundness classification. The percentage of all bulls classified as satisfactory ranged from 49.0% in January to 73.3% in May. The percentage of physically normal bulls with satisfactory semen quality ranged from 65.7% in January to 87.5% in June. Poor body condition or excessive body condition, below average or below the recommended minimum scrotal circumference, lameness, and severe scrotal frostbite significantly reduced the probability of a satisfactory breeding soundness classification. The percentage of sperm with midpiece defects declined significantly and the percentage of sperm with head defects increased significantly with the approach of summer. Photoperiod, cold stress, poor or excessive body condition, and reduced feed quality may interact to reduce semen quality in the winter months.
NASA Astrophysics Data System (ADS)
Zhao, W.; Yang, Zh.; Chen, Zh.; Liu, J.; Wang, W. Ch.; Zheng, W. Yu.
2016-05-01
This study aimed to determine the ripeness of bananas using hyperspectral surface analysis and how a rapid UV-C (ultraviolet-C light) surface treatment could reduce decay. The surface of the banana fruit and its stages of maturity were studied using a hyperspectral imaging technique in the visible and near infrared (370-1000 nm) regions. The vselected color ratios from these spectral images were used for classifying the whole banana into immature, ripe, half-ripe and overripe stages. By using a BP neural network, models based on the wavelengths were developed to predict quality attributes. The mean discrimination rate was 98.17%. The surface of the fresh bananas was treated with UV-C at dosages from 15-55 μW/cm2. The visual qualities with or without UV-C treatment were compared using the image, the chromatic aberration test, the firmness test and the area of black spot on the banana skin. The results showed that high dosages of UV-C damaged the banana skin, while low dosages were more efficient at delaying changes in the relative brightness of the skin. The maximum UV-C treatment dose for satisfactory banana preservation was between 21 and 24 μW/cm2. These results could help to improve the visual quality of bananas and to classify their ripeness more easily.
Feng, Lei; Zhu, Susu; Lin, Fucheng; Su, Zhenzhu; Yuan, Kangpei; Zhao, Yiying; He, Yong; Zhang, Chu
2018-06-15
Mildew damage is a major reason for chestnut poor quality and yield loss. In this study, a near-infrared hyperspectral imaging system in the 874⁻1734 nm spectral range was applied to detect the mildew damage to chestnuts caused by blue mold. Principal component analysis (PCA) scored images were firstly employed to qualitatively and intuitively distinguish moldy chestnuts from healthy chestnuts. Spectral data were extracted from the hyperspectral images. A successive projections algorithm (SPA) was used to select 12 optimal wavelengths. Artificial neural networks, including back propagation neural network (BPNN), evolutionary neural network (ENN), extreme learning machine (ELM), general regression neural network (GRNN) and radial basis neural network (RBNN) were used to build models using the full spectra and optimal wavelengths to distinguish moldy chestnuts. BPNN and ENN models using full spectra and optimal wavelengths obtained satisfactory performances, with classification accuracies all surpassing 99%. The results indicate the potential for the rapid and non-destructive detection of moldy chestnuts by hyperspectral imaging, which would help to develop online detection system for healthy and blue mold infected chestnuts.
Integrated telemedicine workstation for intercontinental grand rounds
NASA Astrophysics Data System (ADS)
Willis, Charles E.; Leckie, Robert G.; Brink, Linda; Goeringer, Fred
1995-04-01
The Telemedicine Spacebridge to Moscow was a series of intercontinental sessions sponsored jointly by NASA and the Moscow Academy of Medicine. To improve the quality of medical images presented, the MDIS Project developed a workstation for acquisition, storage, and interactive display of radiology and pathology images. The workstation was based on a Macintosh IIfx platform with a laser digitizer for radiographs and video capture capability for microscope images. Images were transmitted via the Russian Lyoutch Satellite which had only a single video channel available and no high speed data channels. Two workstations were configured -- one for use at the Uniformed Services University of Health Sciences in Bethesda, MD. and the other for use at the Hospital of the Interior in Moscow, Russia. The two workstations were used may times during 16 sessions. As clinicians used the systems, we modified the original configuration to improve interactive use. This project demonstrated that numerous acquisition and output devices could be brought together in a single interactive workstation. The video images were satisfactory for remote consultation in a grand rounds format.
Sensitive test for sea mine identification based on polarization-aided image processing.
Leonard, I; Alfalou, A; Brosseau, C
2013-12-02
Techniques are widely sought to detect and identify sea mines. This issue is characterized by complicated mine shapes and underwater light propagation dependencies. In a preliminary study we use a preprocessing step for denoising underwater images before applying the algorithm for mine detection. Once a mine is detected, the protocol for identifying it is activated. Among many correlation filters, we have focused our attention on the asymmetric segmented phase-only filter for quantifying the recognition rate because it allows us to significantly increase the number of reference images in the fabrication of this filter. Yet they are not entirely satisfactory in terms of recognition rate and the obtained images revealed to be of low quality. In this report, we propose a way to improve upon this preliminary study by using a single wavelength polarimetric camera in order to denoise the images. This permits us to enhance images and improve depth visibility. We present illustrative results using in situ polarization imaging of a target through a milk-water mixture and demonstrate that our challenging objective of increasing the detection rate and decreasing the false alarm rate has been achieved.
An interactive medical image segmentation framework using iterative refinement.
Kalshetti, Pratik; Bundele, Manas; Rahangdale, Parag; Jangra, Dinesh; Chattopadhyay, Chiranjoy; Harit, Gaurav; Elhence, Abhay
2017-04-01
Segmentation is often performed on medical images for identifying diseases in clinical evaluation. Hence it has become one of the major research areas. Conventional image segmentation techniques are unable to provide satisfactory segmentation results for medical images as they contain irregularities. They need to be pre-processed before segmentation. In order to obtain the most suitable method for medical image segmentation, we propose MIST (Medical Image Segmentation Tool), a two stage algorithm. The first stage automatically generates a binary marker image of the region of interest using mathematical morphology. This marker serves as the mask image for the second stage which uses GrabCut to yield an efficient segmented result. The obtained result can be further refined by user interaction, which can be done using the proposed Graphical User Interface (GUI). Experimental results show that the proposed method is accurate and provides satisfactory segmentation results with minimum user interaction on medical as well as natural images. Copyright © 2017 Elsevier Ltd. All rights reserved.
Reliability of a visual scoring system with fluorescent tracers to assess dermal pesticide exposure.
Aragon, Aurora; Blanco, Luis; Lopez, Lylliam; Liden, Carola; Nise, Gun; Wesseling, Catharina
2004-10-01
We modified Fenske's semi-quantitative 'visual scoring system' of fluorescent tracer deposited on the skin of pesticide applicators and evaluated its reproducibility in the Nicaraguan setting. The body surface of 33 farmers, divided into 31 segments, was videotaped in the field after spraying with a pesticide solution containing a fluorescent tracer. A portable UV lamp was used for illumination in a foldaway dark room. The videos of five farmers were randomly selected. The scoring was based on a matrix with extension of fluorescent patterns (scale 0-5) on the ordinate and intensity (scale 0-5) on the abscissa, with the product of these two ranks as the final score for each body segment (0-25). Five medical students rated and evaluated the quality of 155 video images having undergone 4 h of training. Cronbach alpha coefficients and two-way random effects intraclass correlation coefficients (ICC) with absolute agreement were computed to assess inter-rater reliability. Consistency was high (Cronbach alpha = 0.96), but the scores differed substantially between raters. The overall ICC was satisfactory [0.75; 95% confidence interval (CI) = 0.62-0.83], but it was lower for intensity (0.54; 95% CI = 0.40-0.66) and higher for extension (0.80; 95% CI = 0.71-0.86). ICCs were lowest for images with low scores and evaluated as low quality, and highest for images with high scores and high quality. Inter-rater reliability coefficients indicate repeatability of the scoring system. However, field conditions for recording fluorescence should be improved to achieve higher quality images, and training should emphasize a better mechanism for the reading of body areas with low contamination.
Implementation of the qualities of radiodiagnostic: mammography
NASA Astrophysics Data System (ADS)
Pacífico, L. C.; Magalhães, L. A. G.; Peixoto, J. G. P.; Fernandes, E.
2018-03-01
The objective of the present study was to evaluate the expanded uncertainty of the mammographic calibration process and present the result of the internal audit performed at the Laboratory of Radiological Sciences (LCR). The qualities of the mammographic beans that are references in the LCR, comprises two irradiation conditions: no-attenuated beam and attenuated beam. Both had satisfactory results, with an expanded uncertainty equals 2,1%. The internal audit was performed, and the degree of accordance with the ISO/IEC 17025 was evaluated. The result of the internal audit was satisfactory. We conclude that LCR can perform calibrations on mammography qualities for end users.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-02
... in the United States in a sufficient and reasonably available amount or are not of a satisfactory... sufficient and reasonably available amount or are not of a satisfactory quality; (C) rolling stock or power...
NASA Astrophysics Data System (ADS)
Niu, Kai
Cardiovascular disease and stroke are the leading health problems and causes of death in the US. Due to the minimally invasive nature of the evolution of image guided techniques, interventional radiological procedures are becoming more common and are preferred in treating many cardiovascular diseases and strokes. In addition, with the recent advances in hardware and device technology, the speed and efficacy of interventional treatment has significantly improved. This implies that more image modalities can be developed based on the current C-arm system and patients treated in interventional suites can potentially experience better health outcomes. However, during the treatment patients are irradiated with substantial amounts of ionizing radiation with a high dose rate (digital subtraction angiography (DSA) with 3muGy/frame and 3D cone beam CT image with 0.36muGy/frame for a Siemens Artis Zee biplane system) and/or a long irradiation time (a roadmapping image sequence can be as long as one hour during aneurysm embolization). As a result, the patient entrance dose is extremely high. Despite the fact that the radiation dose is already substantial, image quality is not always satisfactory. By default a temporal average is used in roadmapping images to overcome poor image quality, but this technique can result in motion blurred images. Therefore, reducing radiation dose while maintaining or even improving the image quality is an important area for continued research. This thesis is focused on improving the clinical applications of C-arm cone beam CT systems in two ways: (1) Improve the performance of current image modalities on the C-arm system. (2) Develop new image modalities based on the current system. To be more specific, the objectives are to reduce radiation dose for current modalities (e.g., DSA, fluoroscopy, roadmapping, and cone beam CT) and enable cone beam CT perfusion and time resolved cone beam CT angiography that can be used to diagnose and triage acute ischemic stroke patients more efficiently compared with the current clinical work-flow. The animal and patient cases presented in this thesis are focused towards but not limited to neurointerventional applications.
Sentinel 2A: the image quality performances at the beginning of its mission
NASA Astrophysics Data System (ADS)
Trémas, T.; Lonjou, V.; Lachérade, S.; Languille, F.; Gaudel-Vacaresse, A.,
2016-09-01
Launched on June 23rd, 2015 from Kourou, Sentinel 2A has been providing images for more than 1 year now. The satellite behavior is very satisfactory and the quality of data fulfills the requirements with comfortable margins. The realization and implementation of the satellite has been realized under the responsibility of ESA, for the European Commission. The In Orbit Commissioning phase lasted 4 months, concluded by a review on October 16th, 2015. At this date, the S2A space segment handover took place from the Project Manager (ESA/ESTEC) to the Mission Manager (ESA/ESRIN). The subset of Image Quality commissioning was delegated by ESA to CNES, referring to the experience of the French Space Agency on previous imagers. This phase lasted 7 months after the launch, extending beyond the IOCR. Actually, some parameters required several months before converging to a stable state. This paper presents the status of the satellite, from an IQ prospective, just before it entered its operational phase. The radiometric and geometric performances are listed, including: the absolute radiometric calibration, the equalization, the SNR, the absolute and the multi-temporal location accuracy. The accomplishment of a part of the Global Reference Image over Europe is evoked as well. The IQ commissioning phase ended on January 28th, 2016. From this date, the monitoring of IQ parameters is under the responsibility of ESA/ESRIN. Nevertheless, CNES continues to support ESA to survey the accuracy of S2A performances. The article ends by dealing with the future of S2A that will work together with S2B by the end of 2016.
Adhikari, Srikar
2014-06-01
To compare images obtained using two linear transducers with a different range of frequencies, and to determine if there is a significant difference in the quality of images between the two transducers for medical decision-making. This was a single-blinded, cross-sectional study at an academic medical center. Twenty-five emergency medicine clinical scenarios with ultrasound images (using both 10-5 and 14-5 MHz transducers) covering a variety of point-of-care ultrasound applications were presented to four emergency physician sonographers. They were blinded to the study hypothesis and type of the transducer used to obtain the images. On a scale of 1-10, the mean image quality rating for 10-5 MHz transducer was 7.09 (95 % CI 6.73-7.45) and 6.49 (95 % CI 5.99-6.99) for 14-5 MHz transducer. In the majority of cases (84 %, 95 % CI 75.7-92.3 %), sonographers indicated that images obtained with a 10-5 MHz transducer were satisfactory for medical decision-making. They preferred images obtained with a 10-5 MHz transducer over 14-5 MHz transducer in 39 % (95 % CI 30-50 %) of cases. The images obtained with a 14-5 MHz transducer were preferred over 10-5 MHz transducer in only 16 % (95 % CI 7.7-24.3 %) of the cases. The 14-5 MHz transducer has a slight advantage over 10-5 MHz transducer for ocular, upper airway, and musculoskeletal (tendon) ultrasound applications. A 10-5 MHz linear transducer is adequate to obtain images that can be used for medical decision-making for a variety of point-of-care ultrasound applications.
Mendoza, Patricia; d'Anjou, Marc-André; Carmel, Eric N; Fournier, Eric; Mai, Wilfried; Alexander, Kate; Winter, Matthew D; Zwingenberger, Allison L; Thrall, Donald E; Theoret, Christine
2014-01-01
Understanding radiographic anatomy and the effects of varying patient and radiographic tube positioning on image quality can be a challenge for students. The purposes of this study were to develop and validate a novel technique for creating simulated radiographs using computed tomography (CT) datasets. A DICOM viewer (ORS Visual) plug-in was developed with the ability to move and deform cuboidal volumetric CT datasets, and to produce images simulating the effects of tube-patient-detector distance and angulation. Computed tomographic datasets were acquired from two dogs, one cat, and one horse. Simulated radiographs of different body parts (n = 9) were produced using different angles to mimic conventional projections, before actual digital radiographs were obtained using the same projections. These studies (n = 18) were then submitted to 10 board-certified radiologists who were asked to score visualization of anatomical landmarks, depiction of patient positioning, realism of distortion/magnification, and image quality. No significant differences between simulated and actual radiographs were found for anatomic structure visualization and patient positioning in the majority of body parts. For the assessment of radiographic realism, no significant differences were found between simulated and digital radiographs for canine pelvis, equine tarsus, and feline abdomen body parts. Overall, image quality and contrast resolution of simulated radiographs were considered satisfactory. Findings from the current study indicated that radiographs simulated using this new technique are comparable to actual digital radiographs. Further studies are needed to apply this technique in developing interactive tools for teaching radiographic anatomy and the effects of varying patient and tube positioning. © 2013 American College of Veterinary Radiology.
Petroleum Jelly: A Novel Medium for Ocular Ultrasound.
Engelbert, Patrick R; Palma, James K
2015-08-01
Ocular ultrasound is a useful emergency department imaging modality for evaluation of many conditions, such as retinal detachment, vitreous detachment, vitreous hemorrhage, and elevated intracranial pressure. Obtaining satisfactory ocular ultrasound images requires the use of a medium that eliminates the air interface between the patient's eye and the transducer. Ultrasound gel is most commonly used; however, the use of a transparent dressing applied to the closed eye prior to the application of gel has also been described as a suitable technique. Ocular ultrasound is performed with the high-frequency linear array transducer using a medium to eliminate the air interface between the eye and the transducer. Although ultrasound gel is most frequently used, it can cause minor eye irritation. Placing a transparent dressing over a closed eye prior to application of gel can eliminate the eye irritation. However, our experience in training >500 students in ocular ultrasound has shown that air is frequently introduced underneath the dressing, which leads to poor-quality images. This article introduces petroleum jelly as a medium for ocular ultrasound. By applying a layer of petroleum jelly over the closed eye and allowing it to warm via body heat for 30 to 45 s, this medium can both minimize patient discomfort and provide easily obtainable, high-quality ocular ultrasound images. This article introduces petroleum jelly as a safe, comfortable, and effective medium for ocular ultrasound examination. Published by Elsevier Inc.
An extended algebraic reconstruction technique (E-ART) for dual spectral CT.
Zhao, Yunsong; Zhao, Xing; Zhang, Peng
2015-03-01
Compared with standard computed tomography (CT), dual spectral CT (DSCT) has many advantages for object separation, contrast enhancement, artifact reduction, and material composition assessment. But it is generally difficult to reconstruct images from polychromatic projections acquired by DSCT, because of the nonlinear relation between the polychromatic projections and the images to be reconstructed. This paper first models the DSCT reconstruction problem as a nonlinear system problem; and then extend the classic ART method to solve the nonlinear system. One feature of the proposed method is its flexibility. It fits for any scanning configurations commonly used and does not require consistent rays for different X-ray spectra. Another feature of the proposed method is its high degree of parallelism, which means that the method is suitable for acceleration on GPUs (graphic processing units) or other parallel systems. The method is validated with numerical experiments from simulated noise free and noisy data. High quality images are reconstructed with the proposed method from the polychromatic projections of DSCT. The reconstructed images are still satisfactory even if there are certain errors in the estimated X-ray spectra.
Capranica, Laura; Stager, Joel; Forte, Roberta; Falbo, Simone; Di Baldassarre, Angela; Segura-Garcia, Cristina; Pesce, Caterina
2016-01-01
Although ageing people could benefit from healthy diet and physical activity to maintain health and quality of life, further understandings of the diet- and physical activity-related mechanisms that may cause changes in health and quality of life perception are necessary. The purpose of the study was to investigate the effect of eating attitudes, body mass and image satisfaction, and exercise dependence in the relationship between physical activity and health and quality of life perception in older individuals. Hundred and seventy-nine late middle-aged, (55–64 yrs), young-old (65–74 yrs), and old (75–84 yrs) senior athletes (n = 56), physically active (n = 58) or sedentary adults (n = 65) were submitted to anthropometric evaluations (body mass, height) and self-reported questionnaires: Body Image Dimensional Assessment, Exercise Dependence Scale, Eating Attitude Test, and Short Form Health Survey (Physical Component Summary [PCS] and Mental Component Summary [MCS] of and health and quality of life perception). Senior athletes, physically active, and sedentary participants subgroups differed (P<0.05) from each other in body mass index (BMI) and several components of body image and exercise dependence. Senior athletes showed, compared to their sedentary counterparts, further differences (P<0.05) in eating attitudes and in both PCS and MCS. Mediation analysis showed that the relationship between physical activity habit and MCS, but not PCS, was indirectly explained by a serial mediation chain composed of objective BMI and subjective body image (dis)satisfaction. Findings confirm the relevant role of physically active life habits for older individuals to perceive good physical and mental health. The novelty of the three-path mediated link between physical activity level and mental health perception suggests that the beneficial effect of a physically active lifestyle on weight control can positively impinge on the cognitive-emotional dimension of mental health by ensuring the maintenance, also at older age, of a satisfactory body image. PMID:27611689
Deep learning methods for CT image-domain metal artifact reduction
NASA Astrophysics Data System (ADS)
Gjesteby, Lars; Yang, Qingsong; Xi, Yan; Shan, Hongming; Claus, Bernhard; Jin, Yannan; De Man, Bruno; Wang, Ge
2017-09-01
Artifacts resulting from metal objects have been a persistent problem in CT images over the last four decades. A common approach to overcome their effects is to replace corrupt projection data with values synthesized from an interpolation scheme or by reprojection of a prior image. State-of-the-art correction methods, such as the interpolation- and normalization-based algorithm NMAR, often do not produce clinically satisfactory results. Residual image artifacts remain in challenging cases and even new artifacts can be introduced by the interpolation scheme. Metal artifacts continue to be a major impediment, particularly in radiation and proton therapy planning as well as orthopedic imaging. A new solution to the long-standing metal artifact reduction (MAR) problem is deep learning, which has been successfully applied to medical image processing and analysis tasks. In this study, we combine a convolutional neural network (CNN) with the state-of-the-art NMAR algorithm to reduce metal streaks in critical image regions. Training data was synthesized from CT simulation scans of a phantom derived from real patient images. The CNN is able to map metal-corrupted images to artifact-free monoenergetic images to achieve additional correction on top of NMAR for improved image quality. Our results indicate that deep learning is a novel tool to address CT reconstruction challenges, and may enable more accurate tumor volume estimation for radiation therapy planning.
Sobiecka, Joanna; Gawroński, Wojciech; Kądziołka, Marta; Kruszelnicki, Paweł; Kłodecka-Różalska, Jadwiga; Plinta, Ryszard
2015-11-22
The quality of training conditions affects sporting success, injuries and health. The aim of the work was to present the conditions during the preparations of Polish athletes for the Summer Paralympic Games 2004-2012. The study encompassed 271 paralympians: Athens (91), Beijing (89) and London (91), competing in 13 disciplines. The research was based on a two-part questionnaire by Kłodecka-Różalska adjusted for disabled sports, and was conducted one month before each PG. Part 1 contained 20 closed-ended questions regarding conditions during preparations, while Part 2 concerned socio-demographic and sports-related data. Three levels of conditions: good, satisfactory and poor, were identified. The analysis showed that while the relationships between the athletes were good in all the preparatory periods, the co-operation with the paralympic coaches worsened. The standards of accommodation, food and sports facilities lowered. Personal orthopaedic supply was satisfactory in London; personal sporting equipment was good at all PG. The quality of medical care was the highest in London. The co-operation with physicians, physiotherapists and massage therapists was satisfactory. Consultations with the dietician were sporadic and assessed as poor. Psychological consultations were rare but satisfactory in Beijing and London. Contacts with the mass media were poor at all PG. Although combining private life, work, and education with sport was satisfactory, it was increasingly difficult to manage, particularly before London. The conditions during preparations for the PG 2004-2012 varied. Improvement was noticed only in the quality of medical care and personal orthopaedic supply.
Sobiecka, Joanna; Gawroński, Wojciech; Kądziołka, Marta; Kruszelnicki, Paweł; Kłodecka-Różalska, Jadwiga; Plinta, Ryszard
2015-01-01
The quality of training conditions affects sporting success, injuries and health. The aim of the work was to present the conditions during the preparations of Polish athletes for the Summer Paralympic Games 2004–2012. The study encompassed 271 paralympians: Athens (91), Beijing (89) and London (91), competing in 13 disciplines. The research was based on a two-part questionnaire by Kłodecka-Różalska adjusted for disabled sports, and was conducted one month before each PG. Part 1 contained 20 closed-ended questions regarding conditions during preparations, while Part 2 concerned socio-demographic and sports-related data. Three levels of conditions: good, satisfactory and poor, were identified. The analysis showed that while the relationships between the athletes were good in all the preparatory periods, the co-operation with the paralympic coaches worsened. The standards of accommodation, food and sports facilities lowered. Personal orthopaedic supply was satisfactory in London; personal sporting equipment was good at all PG. The quality of medical care was the highest in London. The co-operation with physicians, physiotherapists and massage therapists was satisfactory. Consultations with the dietician were sporadic and assessed as poor. Psychological consultations were rare but satisfactory in Beijing and London. Contacts with the mass media were poor at all PG. Although combining private life, work, and education with sport was satisfactory, it was increasingly difficult to manage, particularly before London. The conditions during preparations for the PG 2004–2012 varied. Improvement was noticed only in the quality of medical care and personal orthopaedic supply. PMID:26834879
Research of paste transition to substrate in LTCC-technology
NASA Astrophysics Data System (ADS)
Litunov, S. N.; Yurkov, V. Y.
2018-01-01
The electronics development demands for accuracy of printed technologies, in particular, to screen printing. Under a flat blade operation the print form is deformed and the image is distorted relative to the original. A squeegee in a form of a smooth cylinder reduces distortion, but it allows obtaining satisfactory print quality only when using high density grids. The paper shows findings of using roller squeegee with dosed ink supply. The roller squeegee is provided with an elastic layer. Dosage is carried out due to the cells on the elastic layer surface. There were used meshes 100-31 and 120-34 for the stencil. The experiments were carried out with layers of photopolymers and rubber. The carried out calculations made possible to choose the optimum printing pressure. Under the selected conditions, the printed image had minimal distortion. The findings allow drawing a conclusion about the possibility of roller squeegee using in chips manufacture according to LTCC-technology.
NASA Technical Reports Server (NTRS)
Jackson, E. Bruce; Goodrich, Kenneth H.; Bailey, Randall E.; Barnes, James R.; Ragsdale, William A.; Neuhaus, Jason R.
2010-01-01
This paper documents the investigation into the manual docking of a preliminary version of the Crew Exploration Vehicle with stationary and rotating targets in Low Earth Orbit. The investigation was conducted at NASA Langley Research Center in the summer of 2008 in a repurposed fixed-base transport aircraft cockpit and involved nine evaluation astronauts and research pilots. The investigation quantified the benefits of a feed-forward reaction control system thruster mixing scheme to reduce translation-into-rotation coupling, despite unmodeled variations in individual thruster force levels and off-axis center of mass locations up to 12 inches. A reduced rate dead-band in the phase-plane attitude controller also showed some promise. Candidate predictive symbology overlaid on a docking ring centerline camera image did not improve handling qualities, but an innovative attitude status indicator symbol was beneficial. The investigation also showed high workload and handling quality problems when manual dockings were performed with a rotating target. These concerns indicate achieving satisfactory handling quality ratings with a vehicle configuration similar to the nominal Crew Exploration Vehicle may require additional automation.
An RGB colour image steganography scheme using overlapping block-based pixel-value differencing
Pal, Arup Kumar
2017-01-01
This paper presents a steganographic scheme based on the RGB colour cover image. The secret message bits are embedded into each colour pixel sequentially by the pixel-value differencing (PVD) technique. PVD basically works on two consecutive non-overlapping components; as a result, the straightforward conventional PVD technique is not applicable to embed the secret message bits into a colour pixel, since a colour pixel consists of three colour components, i.e. red, green and blue. Hence, in the proposed scheme, initially the three colour components are represented into two overlapping blocks like the combination of red and green colour components, while another one is the combination of green and blue colour components, respectively. Later, the PVD technique is employed on each block independently to embed the secret data. The two overlapping blocks are readjusted to attain the modified three colour components. The notion of overlapping blocks has improved the embedding capacity of the cover image. The scheme has been tested on a set of colour images and satisfactory results have been achieved in terms of embedding capacity and upholding the acceptable visual quality of the stego-image. PMID:28484623
Bednarkiewicz, Artur; Whelan, Maurice P
2008-01-01
Fluorescence lifetime imaging (FLIM) is very demanding from a technical and computational perspective, and the output is usually a compromise between acquisition/processing time and data accuracy and precision. We present a new approach to acquisition, analysis, and reconstruction of microscopic FLIM images by employing a digital micromirror device (DMD) as a spatial illuminator. In the first step, the whole field fluorescence image is collected by a color charge-coupled device (CCD) camera. Further qualitative spectral analysis and sample segmentation are performed to spatially distinguish between spectrally different regions on the sample. Next, the fluorescence of the sample is excited segment by segment, and fluorescence lifetimes are acquired with a photon counting technique. FLIM image reconstruction is performed by either raster scanning the sample or by directly accessing specific regions of interest. The unique features of the DMD illuminator allow the rapid on-line measurement of global good initial parameters (GIP), which are supplied to the first iteration of the fitting algorithm. As a consequence, a decrease of the computation time required to obtain a satisfactory quality-of-fit is achieved without compromising the accuracy and precision of the lifetime measurements.
Exploring Mexican American adolescent romantic relationship profiles and adjustment
Moosmann, Danyel A.V.; Roosa, Mark W.
2015-01-01
Although Mexican Americans are the largest ethnic minority group in the nation, knowledge is limited regarding this population's adolescent romantic relationships. This study explored whether 12th grade Mexican Americans’ (N = 218; 54% female) romantic relationship characteristics, cultural values, and gender created unique latent classes and if so, whether they were linked to adjustment. Latent class analyses suggested three profiles including, relatively speaking, higher, satisfactory, and lower quality romantic relationships. Regression analyses indicated these profiles had distinct associations with adjustment. Specifically, adolescents with higher and satisfactory quality romantic relationships reported greater future family expectations, higher self-esteem, and fewer externalizing symptoms than those with lower quality romantic relationships. Similarly, adolescents with higher quality romantic relationships reported greater academic self-efficacy and fewer sexual partners than those with lower quality romantic relationships. Overall, results suggested higher quality romantic relationships were most optimal for adjustment. Future research directions and implications are discussed. PMID:26141198
A contourlet transform based algorithm for real-time video encoding
NASA Astrophysics Data System (ADS)
Katsigiannis, Stamos; Papaioannou, Georgios; Maroulis, Dimitris
2012-06-01
In recent years, real-time video communication over the internet has been widely utilized for applications like video conferencing. Streaming live video over heterogeneous IP networks, including wireless networks, requires video coding algorithms that can support various levels of quality in order to adapt to the network end-to-end bandwidth and transmitter/receiver resources. In this work, a scalable video coding and compression algorithm based on the Contourlet Transform is proposed. The algorithm allows for multiple levels of detail, without re-encoding the video frames, by just dropping the encoded information referring to higher resolution than needed. Compression is achieved by means of lossy and lossless methods, as well as variable bit rate encoding schemes. Furthermore, due to the transformation utilized, it does not suffer from blocking artifacts that occur with many widely adopted compression algorithms. Another highly advantageous characteristic of the algorithm is the suppression of noise induced by low-quality sensors usually encountered in web-cameras, due to the manipulation of the transform coefficients at the compression stage. The proposed algorithm is designed to introduce minimal coding delay, thus achieving real-time performance. Performance is enhanced by utilizing the vast computational capabilities of modern GPUs, providing satisfactory encoding and decoding times at relatively low cost. These characteristics make this method suitable for applications like video-conferencing that demand real-time performance, along with the highest visual quality possible for each user. Through the presented performance and quality evaluation of the algorithm, experimental results show that the proposed algorithm achieves better or comparable visual quality relative to other compression and encoding methods tested, while maintaining a satisfactory compression ratio. Especially at low bitrates, it provides more human-eye friendly images compared to algorithms utilizing block-based coding, like the MPEG family, as it introduces fuzziness and blurring instead of artificial block artifacts.
41 CFR 51-6.11 - Quality complaints.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Quality complaints. 51-6... § 51-6.11 Quality complaints. (a) When the quality of a commodity received is not considered.... (b) When the quality of a service is not considered satisfactory by the contracting activity, it...
Diagnostic value of the fluoroscopic triggering 3D LAVA technique for primary liver cancer.
Shen, Xiao-Yong; Chai, Chun-Hua; Xiao, Wen-Bo; Wang, Qi-Dong
2010-04-01
Primary liver cancer (PLC) is one of the common malignant tumors. Liver acquisition with acceleration volume acquisition (LAVA), which allows simultaneous dynamic enhancement of the hepatic parenchyma and vasculature imaging, is of great help in the diagnosis of PLC. This study aimed to evaluate application of the fluoroscopic triggering 3D LAVA technique in the imaging of PLC and liver vasculature. The clinical data and imaging findings of 38 adults with PLC (22 men and 16 women; average age 52 years), pathologically confirmed by surgical resection or biopsy, were collected and analyzed. All magnetic resonance images were obtained with a 1.5-T system (General Electrics Medical Systems) with an eight-element body array coil and application of the fluoroscopic triggering 3D LAVA technique. Overall image quality was assessed on a 5-point scale by two experienced radiologists. All the nodules and blood vessel were recorded and compared. The diagnostic accuracy and feasibility of LAVA were evaluated. Thirty-eight patients gave high quality images of 72 nodules in the liver for diagnosis. The accuracy of LAVA was 97.2% (70/72), and the coincidence rate between the extent of tumor judged by dynamic enhancement and pathological examination was 87.5% (63/72). Displayed by the maximum intensity projection reconstruction, nearly all cases gave satisfactory images of branches III and IV of the hepatic artery. Furthermore, small early-stage enhancing hepatic lesions and the parallel portal vein were also well displayed. Sequence of LAVA provides good multi-phase dynamic enhancement scanning of hepatic lesions. Combined with conventional scanning technology, LAVA effectively and safely displays focal hepatic lesions and the relationship between tumor and normal tissues, especially blood vessels.
A Bayesian framework for extracting human gait using strong prior knowledge.
Zhou, Ziheng; Prügel-Bennett, Adam; Damper, Robert I
2006-11-01
Extracting full-body motion of walking people from monocular video sequences in complex, real-world environments is an important and difficult problem, going beyond simple tracking, whose satisfactory solution demands an appropriate balance between use of prior knowledge and learning from data. We propose a consistent Bayesian framework for introducing strong prior knowledge into a system for extracting human gait. In this work, the strong prior is built from a simple articulated model having both time-invariant (static) and time-variant (dynamic) parameters. The model is easily modified to cater to situations such as walkers wearing clothing that obscures the limbs. The statistics of the parameters are learned from high-quality (indoor laboratory) data and the Bayesian framework then allows us to "bootstrap" to accurate gait extraction on the noisy images typical of cluttered, outdoor scenes. To achieve automatic fitting, we use a hidden Markov model to detect the phases of images in a walking cycle. We demonstrate our approach on silhouettes extracted from fronto-parallel ("sideways on") sequences of walkers under both high-quality indoor and noisy outdoor conditions. As well as high-quality data with synthetic noise and occlusions added, we also test walkers with rucksacks, skirts, and trench coats. Results are quantified in terms of chamfer distance and average pixel error between automatically extracted body points and corresponding hand-labeled points. No one part of the system is novel in itself, but the overall framework makes it feasible to extract gait from very much poorer quality image sequences than hitherto. This is confirmed by comparing person identification by gait using our method and a well-established baseline recognition algorithm.
Equine sperm-bound antisperm antibodies are associated with poor semen quality.
Ferrer, M S; Miller, L M J
2018-06-01
Antisperm antibodies (ASAs) have been associated with infertility in stallions. The objectives of this study were to investigate the frequency of ASA-positive semen samples in satisfactory and non-satisfactory breeder stallions, the association between ASA binding and semen quality, and factors that may affect the diagnosis. Breeding soundness examinations were performed in 21 stallions and the percentage of IgG- and IgA-bound spermatozoa was evaluated using flow cytometry. Median IgG and IgA binding did not differ between the first and second ejaculates. The percentage of IgA-bound spermatozoa was higher in non-satisfactory (n = 10) than satisfactory breeder stallions (n = 11). However, IgG binding or frequency of IgG-positive ejaculates did not differ with stallion classification. The IgG-positive stallions had significantly lower total sperm motility, concentration and total numbers than IgG-negative stallions in the first ejaculate, and lower sperm concentration in the second ejaculate. The IgA-positive stallions had lower total sperm motility, normal spermatozoa and total numbers than IgA-negative stallions in the first ejaculate, and lower total sperm motility, normal spermatozoa and total numbers in the second ejaculate. While IgG binding did not differ with season, IgA binding was higher in the non-breeding season (n = 6 stallions) than the breeding season (n = 15 stallions) in the first ejaculate. Stallion age did not differ with ASA classification. In conclusion, IgG binding was highly prevalent in both groups of stallions, while IgA binding was higher and more prevalent in non-satisfactory breeders. Both isotypes were associated with poor semen quality. Season and sexual rest had an effect on IgA but not IgG binding. Copyright © 2018 Elsevier Inc. All rights reserved.
Seo, Eun Hee; Kim, Tae Oh; Park, Min Jae; Joo, Hee Rin; Heo, Nae Yun; Park, Jongha; Park, Seung Ha; Yang, Sung Yeon; Moon, Young Soo
2012-03-01
Several factors influence bowel preparation quality. Recent studies have indicated that the time interval between bowel preparation and the start of colonoscopy is also important in determining bowel preparation quality. To evaluate the influence of the preparation-to-colonoscopy (PC) interval (the interval of time between the last polyethylene glycol dose ingestion and the start of the colonoscopy) on bowel preparation quality in the split-dose method for colonoscopy. Prospective observational study. University medical center. A total of 366 consecutive outpatients undergoing colonoscopy. Split-dose bowel preparation and colonoscopy. The quality of bowel preparation was assessed by using the Ottawa Bowel Preparation Scale according to the PC interval, and other factors that might influence bowel preparation quality were analyzed. Colonoscopies with a PC interval of 3 to 5 hours had the best bowel preparation quality score in the whole, right, mid, and rectosigmoid colon according to the Ottawa Bowel Preparation Scale. In multivariate analysis, the PC interval (odds ratio [OR] 1.85; 95% CI, 1.18-2.86), the amount of PEG ingested (OR 4.34; 95% CI, 1.08-16.66), and compliance with diet instructions (OR 2.22l 95% CI, 1.33-3.70) were significant contributors to satisfactory bowel preparation. Nonrandomized controlled, single-center trial. The optimal time interval between the last dose of the agent and the start of colonoscopy is one of the important factors to determine satisfactory bowel preparation quality in split-dose polyethylene glycol bowel preparation. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
Teaching Quality and Student Satisfaction: Nexus or Simulacrum?
ERIC Educational Resources Information Center
Beecham, Rod
2009-01-01
Quality has clear meanings when associated with specific phenomena. The relative nature of quality in commercial contexts, specifically in relation to manufactured goods, has been studied. In service industries there is no satisfactory indicator of quality. The Likert-scale questionnaire does not allow the researcher to distinguish between…
Zhang, Yuyang; Xing, Zhen; She, Dejun; Huang, Nan; Cao, Dairong
The aim of this study was to prospectively evaluate the repeatability of non-contrast-enhanced lower-extremity magnetic resonance angiography using the flow-spoiled fresh blood imaging (FS-FBI). Forty-three healthy volunteers and 15 patients with lower-extremity arterial stenosis were recruited in this study and were examined by FS-FBI. Digital subtraction angiography was performed within a week after the FS-FBI in the patient group. Repeatability was assessed by the following parameters: grading of image quality, diameter and area of major arteries, and grading of stenosis of lower-extremity arteries. Two experienced radiologists blinded for patient data independently evaluated the FS-FBI and digital subtraction angiography images. Intraclass correlation coefficients (ICCs), sensitivity, and specificity were used for statistical analysis. The grading of image quality of most data was satisfactory. The ICCs for the first and second measures were 0.792 and 0.884 in the femoral segment and 0.803 and 0.796 in the tibiofibular segment for healthy volunteer group, 0.873 and 1.000 in the femoral segment, and 0.737 and 0.737 in the tibiofibular segment for the patient group. Intraobserver and interobserver agreements on diameter and area of arteries were excellent, with ICCs mostly greater than 0.75 in the volunteer group. For stenosis grading analysis, intraobserver ICCs range from 0.784 to 0.862 and from 0.778 to 0.854, respectively. Flow-spoiled fresh blood imaging yielded a mean sensitivity and specificity to detect arterial stenosis or occlusion of 90% and 80% for femoral segment and 86.7% and 93.3% for tibiofibular segment at least. Lower-extremity angiography with FS-FBI is a reliable and reproducible screening tool for lower-extremity atherosclerotic disease, especially for patients with impaired renal function.
[The 18F-FDG myocardial metabolic imaging in twenty seven pilots with regular aerobic training].
Fang, Ting-Zheng; Zhu, Jia-Rui; Chuan, Ling; Zhao, Wen-Rui; Xu, Gen-Xiang; Yang, Min-Fu; He, Zuo-Xiang
2009-02-01
To evaluate the characteristics of myocardial (18)F-FDG imaging in pilots with regular aerobic exercise training. Twenty seven healthy male pilots with regular aerobic exercise training were included in this study. The subjects were divided into fasting (n = 17) or non-fasting group (n = 10). Fluorine-18-labeled deoxyglucose and Tc-99m-sestamibi dual-nuclide myocardial imaging were obtained at rest and at target heart rate during bicycle ergometer test. The exercise and rest myocardial perfusion imaging were analyzed for myocardial ischemia presence. The myocardial metabolism imaging was analyzed with the visual semi-quantitative analyses model of seventeen segments. The secondary-extreme heart rate (195-age) was achieved in all subjects. There was no myocardial ischemia in all perfusion imaging. In the visual qualitative analyses, four myocardial metabolism imaging failed in the fasting group while one failed in the non-fasting group (P > 0.05). In the visual semi-quantitative analyses, myocardial metabolism imaging scores at rest or exercise in all segments were similar between two groups (P > 0.05). In the fasting group, the myocardial metabolism imaging scores during exercise were significantly higher than those at rest in 6 segments (P < 0.05). In the non-fasting group, the scores of 3 exercise myocardial metabolism imaging were significantly higher than those at rest (P < 0.05). Satisfactory high-quality myocardial metabolism imaging could be obtained at fasting and exercise situations in subjects with regular aerobic exercise.
Mora, Patricia; Faulkner, Keith; Mahmoud, Ahmed M; Gershan, Vesna; Kausik, Aruna; Zdesar, Urban; Brandan, María-Ester; Kurt, Serap; Davidović, Jasna; Salama, Dina H; Aribal, Erkin; Odio, Clara; Chaturvedi, Arvind K; Sabih, Zahida; Vujnović, Saša; Paez, Diana; Delis, Harry
2018-04-01
The International Atomic Energy Agency (IAEA) through a Coordinated Research Project on "Enhancing Capacity for Early Detection and Diagnosis of Breast Cancer through Imaging", brought together a group of mammography radiologists, medical physicists and radiographers; to investigate current practices and improve procedures for the early detection of breast cancer by strengthening both the clinical and medical physics components. This paper addresses the medical physics component. The countries that participated in the CRP were Bosnia and Herzegovina, Costa Rica, Egypt, India, Kenya, the Frmr. Yug. Rep. of Macedonia, Mexico, Nigeria, Pakistan, Philippines, Slovenia, Turkey, Uganda, United Kingdom and Zambia. Ten institutions participated using IAEA quality control protocols in 9 digital and 3 analogue mammography equipment. A spreadsheet for data collection was generated and distributed. Evaluation of image quality was done using TOR MAX and DMAM2 Gold phantoms. QC results for analogue equipment showed satisfactory results. QC tests performed on digital systems showed that improvements needed to be implemented, especially in thickness accuracy, signal difference to noise ratio (SDNR) values for achievable levels, uniformity and modulation transfer function (MTF). Mean glandular dose (MGD) was below international recommended levels for patient radiation protection. Evaluation of image quality by phantoms also indicated the need for improvement. Common activities facilitated improvement in mammography practice, including training of medical physicists in QC programs and infrastructure was improved and strengthened; networking among medical physicists and radiologists took place and was maintained over time. IAEA QC protocols provided a uniformed approach to QC measurements. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Characterization of European sword blades through neutron imaging techniques
NASA Astrophysics Data System (ADS)
Salvemini, F.; Grazzi, F.; Peetermans, S.; Gener, M.; Lehmann, E. H.; Zoppi, M.
2014-09-01
In the present work, we have studied two European rapier blades, dating back to the period ranging from the Late Renaissance to the Early Modern Age (about 17th to 18th century). In order to determine variation in quality and differences in technology, a study was undertaken with the purpose to observe variations in the blade microstructure (and consequently in the construction processes). The samples, which in the present case were expendable, have been investigated, preliminarily, through standard metallography and then by means of white beam and energy-selective neutron imaging. The comparison of the results, using the two techniques, turned out to be satisfactory, with a substantial quantitative agreement of the results obtained with the two techniques, and show the complementarity of the two methods. Metallography has been considered up to now the method of choice for metal material characterization. The correspondence between the two methods, as well as the non-invasive character of the neutron-based techniques and its possibility to obtain 3D reconstruction, candidate neutron imaging as an important and quantitatively reliable technique for metal characterization.
Quality of commercially produced Shigella serogrouping and serotyping antisera.
Evins, G M; Gheesling, L L; Tauxe, R V
1988-01-01
Shigella grouping antisera from five manufacturers and typing antisera from two were purchased and evaluated with homologous and heterologous Shigella strains in the slide agglutination test. Only 31 of 73 (42%) antisera were satisfactory. In many instances, the antisera gave negative, as opposed to weak, reactions when they should have given strong positive reactions. Four reagents cross-reacted with Shigella strains. Of the 19 polyvalent grouping antisera to subgroups Shigella dysenteriae serotypes 1 through 7, S. flexneri serotypes 1 through 6, S. boydii serotypes 1 through 7, and S. sonnei forms I, II, only one S. sonnei reagent and five S. flexneri reagents were satisfactory with greater than or equal to 90% of the homologous strains. The reagent of poorest quality was satisfactory with only 18% of the homologous strains. There were three polyvalent antisera to the higher types of S. dysenteriae and S. boydii, which were available from only one company, that adequately identified 80, 63, and 65% of the homologous strains. Typing antisera were available from only two companies, and 30 of 51 (59%) were satisfactory. Commercially available Shigella antisera are inadequate for the laboratory testing required for planning the development of and evaluating Shigella vaccines. PMID:3281972
The Impact of Financial Crisis on the Quality of Life
ERIC Educational Resources Information Center
Rova, Lindita; Mano, Romeo
2009-01-01
The quality of life is a relatively new concept, which is continually changing and for which there is not yet a wholly satisfactory definition. The quality of life involves human, social-economic and health characteristics. The manifold nature of the quality of life led to the development of various patterns for measuring it. The quality of life…
Summary of the effects of engine throttle response on airplane formation-flying qualities
NASA Technical Reports Server (NTRS)
Walsh, Kevin R.
1993-01-01
A flight evaluation was conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. This airplane was chosen because of its known, very favorable thrust response characteristics. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. The Cooper and Harper Pilot Rating Scale was used to assign levels of handling quality. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented. These results may provide engine manufacturers with guidelines to assure satisfactory handling qualities in future engine designs.
Silveira, Patricia C.; Dunne, Ruth; Sainani, Nisha I.; Lacson, Ronilda; Silverman, Stuart G.; Tempany, Clare M.; Khorasani, Ramin
2015-01-01
Rationale and Objectives Assess the impact of implementing a structured report template and a computer-aided diagnosis (CAD) tool on the quality of prostate multiparametric MRI (mp-MRI) reports. Materials and Methods Institutional Review Board approval was obtained for this HIPAA-compliant study performed at an academic medical center. The study cohort included all prostate mp-MRI reports (n=385) finalized 6 months before and after implementation of a structured report template and a CAD tool (collectively the IT tools) integrated into the PACS workstation. Primary outcome measure was quality of prostate mp-MRI reports. An expert panel of our institution’s subspecialty trained abdominal radiologists defined prostate mp-MRI report quality as optimal, satisfactory or unsatisfactory based on documentation of 9 variables. Reports were reviewed to extract the predefined quality variables and determine whether the IT tools were used to create each report. Chi-square and Student’s t-tests were used to compare report quality before and after implementation of IT tools. Results The overall proportion of optimal or satisfactory reports increased from 29.8% (47/158) to 53.3% (121/227) (p<0.001) after implementing the IT tools. While the proportion of optimal or satisfactory reports increased among reports generated using at least one of the IT tools (47/158=[29.8%] vs. 105/161=[65.2%]; p<0.001), there was no change in quality among reports generated without use of the IT tools (47/158=[29.8%] vs. 16/66=[24.2%]; p=0.404). Conclusion The use of a structured template and CAD tool improved the quality of prostate mp-MRI reports compared to free-text report format and subjective measurement of contrast enhancement kinetic curve. PMID:25863794
PET Image Reconstruction Incorporating 3D Mean-Median Sinogram Filtering
NASA Astrophysics Data System (ADS)
Mokri, S. S.; Saripan, M. I.; Rahni, A. A. Abd; Nordin, A. J.; Hashim, S.; Marhaban, M. H.
2016-02-01
Positron Emission Tomography (PET) projection data or sinogram contained poor statistics and randomness that produced noisy PET images. In order to improve the PET image, we proposed an implementation of pre-reconstruction sinogram filtering based on 3D mean-median filter. The proposed filter is designed based on three aims; to minimise angular blurring artifacts, to smooth flat region and to preserve the edges in the reconstructed PET image. The performance of the pre-reconstruction sinogram filter prior to three established reconstruction methods namely filtered-backprojection (FBP), Maximum likelihood expectation maximization-Ordered Subset (OSEM) and OSEM with median root prior (OSEM-MRP) is investigated using simulated NCAT phantom PET sinogram as generated by the PET Analytical Simulator (ASIM). The improvement on the quality of the reconstructed images with and without sinogram filtering is assessed according to visual as well as quantitative evaluation based on global signal to noise ratio (SNR), local SNR, contrast to noise ratio (CNR) and edge preservation capability. Further analysis on the achieved improvement is also carried out specific to iterative OSEM and OSEM-MRP reconstruction methods with and without pre-reconstruction filtering in terms of contrast recovery curve (CRC) versus noise trade off, normalised mean square error versus iteration, local CNR versus iteration and lesion detectability. Overall, satisfactory results are obtained from both visual and quantitative evaluations.
Janković, Slavenka; Vukićević, Jelica; Djordjević, Sanja; Janković, Janko; Marinković, Jelena; Erić, Miloš
2013-01-01
The Children's Dermatology Life Quality Index (CDLQI) evaluates the impact of skin diseases on the patient's quality of life. The purpose of the study was to translate and to validate the CDLQI into Serbian. The CDLQI was translated into Serbian following international recommendations for translation and cultural adaptation. The validation study was carried out on a large cohort of secondary schoolchildren who self-reported acne. Translating the CDLQI consisted of forward translation, reconciliation, back translation, back-translation review, and cognitive debriefing. The good internal consistency of the scale was demonstrated with a Cronbach alpha coefficient of 0.87. A Spearman correlation coefficient of 0.66 between the CDLQI and the Cardiff Acne Disability Index (CADI) was deemed satisfactory to demonstrate concurrent validity. The translation, cross-cultural adaptation, and psychometric qualities of the CDLQI were satisfactory, enabling its application in clinical practice and future studies.
Aging and quality of life of elderly people in rural areas.
Garbaccio, Juliana Ladeira; Tonaco, Luís Antônio Batista; Estêvão, Wilson Goulart; Barcelos, Bárbara Jacome
2018-01-01
To evaluate the quality of life and health of elderly in rural areas of Minas Gerais State's center-west. Cross-sectional study, in four municipalities of Minas Gerais State, by interviewing elderly people. Associations between socio-demographic and quality of life variables were tested, separated into "satisfactory"/"unsatisfactory" with values from the median of positive answers. It was used the chi-square test, Fisher's test and regression. 182 elderly answered the questions and showed a relation with the "satisfactory" quality of life - bivariate (p < 0.05): age by 69 years (61.6%), married (61.7%), living by 54 years in rural areas (68%), with no financial support (59.5%), living with someone else (61%), non-smoker (60%), presenting good health (76.7%), satisfied with life (69.6%); regression: not having financial support, living with someone else and not smoking. Elderly people in rural areas present good quality of life/health in the cognitive aspect, access to services, goods, habits, but awareness must be constant due to their weakness.
Telles, Rosa Weiss; Costa-Silva, Luciana; Machado, Luciana A C; Reis, Rodrigo Citton Padilha Dos; Barreto, Sandhi Maria
To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). A test-retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5mm and ≤1.7mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference=1.08; coefficient of variation (%CV)=54.68%; intraclass correlation coefficient (ICC) (95%CI)=0.59 (0.34-0.77)]; JSW [SD of mean difference=0.34-0.61; %CV=4.48%-9.80%; ICC (95%CI)=0.74 (0.55-0.85)-0.94 (0.87-0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK. Copyright © 2016. Published by Elsevier Editora Ltda.
Least-squares reverse time migration in elastic media
NASA Astrophysics Data System (ADS)
Ren, Zhiming; Liu, Yang; Sen, Mrinal K.
2017-02-01
Elastic reverse time migration (RTM) can yield accurate subsurface information (e.g. PP and PS reflectivity) by imaging the multicomponent seismic data. However, the existing RTM methods are still insufficient to provide satisfactory results because of the finite recording aperture, limited bandwidth and imperfect illumination. Besides, the P- and S-wave separation and the polarity reversal correction are indispensable in conventional elastic RTM. Here, we propose an iterative elastic least-squares RTM (LSRTM) method, in which the imaging accuracy is improved gradually with iteration. We first use the Born approximation to formulate the elastic de-migration operator, and employ the Lagrange multiplier method to derive the adjoint equations and gradients with respect to reflectivity. Then, an efficient inversion workflow (only four forward computations needed in each iteration) is introduced to update the reflectivity. Synthetic and field data examples reveal that the proposed LSRTM method can obtain higher-quality images than the conventional elastic RTM. We also analyse the influence of model parametrizations and misfit functions in elastic LSRTM. We observe that Lamé parameters, velocity and impedance parametrizations have similar and plausible migration results when the structures of different models are correlated. For an uncorrelated subsurface model, velocity and impedance parametrizations produce fewer artefacts caused by parameter crosstalk than the Lamé coefficient parametrization. Correlation- and convolution-type misfit functions are effective when amplitude errors are involved and the source wavelet is unknown, respectively. Finally, we discuss the dependence of elastic LSRTM on migration velocities and its antinoise ability. Imaging results determine that the new elastic LSRTM method performs well as long as the low-frequency components of migration velocities are correct. The quality of images of elastic LSRTM degrades with increasing noise.
How Chinese Semantics Capability Improves Interpretation in Visual Communication
ERIC Educational Resources Information Center
Cheng, Chu-Yu; Ou, Yang-Kun; Kin, Ching-Lung
2017-01-01
A visual representation involves delivering messages through visually communicated images. The study assumed that semantic recognition can affect visual interpretation ability, and the result showed that students graduating from a general high school achieve satisfactory results in semantic recognition and image interpretation tasks than students…
On-rail solution for autonomous inspections in electrical substations
NASA Astrophysics Data System (ADS)
Silva, Bruno P. A.; Ferreira, Rafael A. M.; Gomes, Selson C.; Calado, Flavio A. R.; Andrade, Roberto M.; Porto, Matheus P.
2018-05-01
This work presents an alternative solution for autonomous inspections in electrical substations. The autonomous system is a robot that moves on rails, collects infrared and visible images of selected targets, also processes the data and predicts the components lifetime. The robot moves on rails to overcome difficulties found in not paved substations commonly encountered in Brazil. We take advantage of using rails to convey the data by them, minimizing the electromagnetic interference, and at the same time transmitting electrical energy to feed the autonomous system. As part of the quality control process, we compared thermographic inspections made by the robot with inspections made by a trained thermographer using a scientific camera Flir® SC660. The results have shown that the robot achieved satisfactory results, identifying components and measuring temperature accurately. The embodied routine considers the weather changes along the day, providing a standard result of the components thermal response, also gives the uncertainty of temperature measurement, contributing to the quality in the decision making process.
Pre- and posttreatment techniques for spacecraft water recovery
NASA Technical Reports Server (NTRS)
Putnam, David F.; Colombo, Gerald V.; Michalek, William F.
1987-01-01
The objective was to develop techniques for satisfactory pretreatment of waste water (urine and wash water) prior to recovery by distillation and satisfactory post-treatment of the recovered water and humidity condensate for purification to the high quality necessary for reuse. The effort included literature and laboratory investigations, feasibility evaluations of candidate approaches, and development of conceptual designs for a waste water pretreatment system and a recovered water post-treatment system.
A service protocol for post-processing of medical images on the mobile device
NASA Astrophysics Data System (ADS)
He, Longjun; Ming, Xing; Xu, Lang; Liu, Qian
2014-03-01
With computing capability and display size growing, the mobile device has been used as a tool to help clinicians view patient information and medical images anywhere and anytime. It is uneasy and time-consuming for transferring medical images with large data size from picture archiving and communication system to mobile client, since the wireless network is unstable and limited by bandwidth. Besides, limited by computing capability, memory and power endurance, it is hard to provide a satisfactory quality of experience for radiologists to handle some complex post-processing of medical images on the mobile device, such as real-time direct interactive three-dimensional visualization. In this work, remote rendering technology is employed to implement the post-processing of medical images instead of local rendering, and a service protocol is developed to standardize the communication between the render server and mobile client. In order to make mobile devices with different platforms be able to access post-processing of medical images, the Extensible Markup Language is taken to describe this protocol, which contains four main parts: user authentication, medical image query/ retrieval, 2D post-processing (e.g. window leveling, pixel values obtained) and 3D post-processing (e.g. maximum intensity projection, multi-planar reconstruction, curved planar reformation and direct volume rendering). And then an instance is implemented to verify the protocol. This instance can support the mobile device access post-processing of medical image services on the render server via a client application or on the web page.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-17
... the Arizona State Implementation Plan, Pinal County Air Quality Control District AGENCY: Environmental... disapproval of a revision to the Pinal County Air Quality Control District portion of the Arizona State... the Control Officer to determine whether the manner of control of fugitive emissions is satisfactory...
NASA Astrophysics Data System (ADS)
Liang, Yu-Li
Multimedia data is increasingly important in scientific discovery and people's daily lives. Content of massive multimedia is often diverse and noisy, and motion between frames is sometimes crucial in analyzing those data. Among all, still images and videos are commonly used formats. Images are compact in size but do not contain motion information. Videos record motion but are sometimes too big to be analyzed. Sequential images, which are a set of continuous images with low frame rate, stand out because they are smaller than videos and still maintain motion information. This thesis investigates features in different types of noisy sequential images, and the proposed solutions that intelligently combined multiple features to successfully retrieve visual information from on-line videos and cloudy satellite images. The first task is detecting supraglacial lakes above ice sheet in sequential satellite images. The dynamics of supraglacial lakes on the Greenland ice sheet deeply affect glacier movement, which is directly related to sea level rise and global environment change. Detecting lakes above ice is suffering from diverse image qualities and unexpected clouds. A new method is proposed to efficiently extract prominent lake candidates with irregular shapes, heterogeneous backgrounds, and in cloudy images. The proposed system fully automatize the procedure that track lakes with high accuracy. We further cooperated with geoscientists to examine the tracked lakes and found new scientific findings. The second one is detecting obscene content in on-line video chat services, such as Chatroulette, that randomly match pairs of users in video chat sessions. A big problem encountered in such systems is the presence of flashers and obscene content. Because of various obscene content and unstable qualities of videos capture by home web-camera, detecting misbehaving users is a highly challenging task. We propose SafeVchat, which is the first solution that achieves satisfactory detection rate by using facial features and skin color model. To harness all the features in the scene, we further developed another system using multiple types of local descriptors along with Bag-of-Visual Word framework. In addition, an investigation of new contour feature in detecting obscene content is presented.
USGS Laboratory Review Program Ensures Analytical Quality
Erdmann, David E.
1995-01-01
The USGS operates a review program for laboratories that analyze samples for USGS environmental investigations. This program has been effective in providing QA feedback to laboratories while ensuring that analytical data are consistent, of satisfactory quality, and meet the data objectives of the investigation.
Assessing Students' Spiritual and Religious Qualities
ERIC Educational Resources Information Center
Astin, Alexander W.; Astin, Helen S.; Lindholm, Jennifer A.
2011-01-01
This paper describes a comprehensive set of 12 new measures for studying undergraduate students' spiritual and religious development. The three measures of spirituality, four measures of "spiritually related" qualities, and five measures of religiousness demonstrate satisfactory reliability, robustness, and both concurrent and predictive validity.…
NASA Astrophysics Data System (ADS)
Bondareva, A. P.; Cheremkhin, P. A.; Evtikhiev, N. N.; Krasnov, V. V.; Starikov, S. N.
Scheme of optical image encryption with digital information input and dynamic encryption key based on two liquid crystal spatial light modulators and operating with spatially-incoherent monochromatic illumination is experimentally implemented. Results of experiments on images optical encryption and numerical decryption are presented. Satisfactory decryption error of 0.20÷0.27 is achieved.
A new level set model for cell image segmentation
NASA Astrophysics Data System (ADS)
Ma, Jing-Feng; Hou, Kai; Bao, Shang-Lian; Chen, Chun
2011-02-01
In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing.
Effect of pronase as mucolytic agent on imaging quality of magnifying endoscopy.
Kim, Gwang Ha; Cho, Yu Kyung; Cha, Jae Myung; Lee, Sun-Young; Chung, Il-Kwun
2015-02-28
To investigate the efficacy of premedication with pronase, a proteolytic enzyme, in improving image quality during magnifying endoscopy. The study was of a blinded, randomized, prospective design. Patients were assigned to groups administered oral premedication of either pronase and simethicone (Group A) or simethicone alone (Group B). First, the gastric mucosal visibility grade (1-4) was determined during conventional endoscopy, and then a magnifying endoscopic examination was conducted. The quality of images obtained by magnifying endoscopy at the stomach and the esophagus was scored from 1 to 3, with a lower score indicating better visibility. The endoscopist used water flushes as needed to obtain satisfactory magnifying endoscopic views. The main study outcomes were the visibility scores during magnifying endoscopy and the number of water flushes. A total of 144 patients were enrolled, and data from 143 patients (M:F=90:53, mean age 57.5 years) were analyzed. The visibility score was significantly higher in the stomach following premedication with pronase (73% with a score of 1 in Group A vs 49% in Group B, P<0.05), but there was no difference in the esophagus visibility scores (67% with a score of 1 in Group A vs 58% in Group B). Fewer water flushes [mean 0.7±0.9 times (range: 0-3 times) in Group A vs 1.9±1.5 times (range: 0-6 times) in Group B, P<0.05] in the pronase premedication group did not affect the endoscopic procedure times [mean 766 s (range: 647-866 s) for Group A vs 760 s (range: 678-854 s) for Group B, P=0.88]. The total gastric mucosal visibility score was also lower in Group A (4.9±1.5 vs 8.3±1.8 in Group B, P<0.01). The addition of pronase to simethicone premedication resulted in clearer images during magnifying endoscopy and reduced the need for water flushes.
Effect of pronase as mucolytic agent on imaging quality of magnifying endoscopy
Kim, Gwang Ha; Cho, Yu Kyung; Cha, Jae Myung; Lee, Sun-Young; Chung, Il-Kwun
2015-01-01
AIM: To investigate the efficacy of premedication with pronase, a proteolytic enzyme, in improving image quality during magnifying endoscopy. METHODS: The study was of a blinded, randomized, prospective design. Patients were assigned to groups administered oral premedication of either pronase and simethicone (Group A) or simethicone alone (Group B). First, the gastric mucosal visibility grade (1-4) was determined during conventional endoscopy, and then a magnifying endoscopic examination was conducted. The quality of images obtained by magnifying endoscopy at the stomach and the esophagus was scored from 1 to 3, with a lower score indicating better visibility. The endoscopist used water flushes as needed to obtain satisfactory magnifying endoscopic views. The main study outcomes were the visibility scores during magnifying endoscopy and the number of water flushes. RESULTS: A total of 144 patients were enrolled, and data from 143 patients (M:F = 90:53, mean age 57.5 years) were analyzed. The visibility score was significantly higher in the stomach following premedication with pronase (73% with a score of 1 in Group A vs 49% in Group B, P < 0.05), but there was no difference in the esophagus visibility scores (67% with a score of 1 in Group A vs 58% in Group B). Fewer water flushes [mean 0.7 ± 0.9 times (range: 0-3 times) in Group A vs 1.9 ± 1.5 times (range: 0-6 times) in Group B, P < 0.05] in the pronase premedication group did not affect the endoscopic procedure times [mean 766 s (range: 647-866 s) for Group A vs 760 s (range: 678-854 s) for Group B, P = 0.88]. The total gastric mucosal visibility score was also lower in Group A (4.9 ± 1.5 vs 8.3 ± 1.8 in Group B, P < 0.01). CONCLUSION: The addition of pronase to simethicone premedication resulted in clearer images during magnifying endoscopy and reduced the need for water flushes. PMID:25741158
Accurate and cost-effective MTF measurement system for lens modules of digital cameras
NASA Astrophysics Data System (ADS)
Chang, Gao-Wei; Liao, Chia-Cheng; Yeh, Zong-Mu
2007-01-01
For many years, the widening use of digital imaging products, e.g., digital cameras, has given rise to much attention in the market of consumer electronics. However, it is important to measure and enhance the imaging performance of the digital ones, compared to that of conventional cameras (with photographic films). For example, the effect of diffraction arising from the miniaturization of the optical modules tends to decrease the image resolution. As a figure of merit, modulation transfer function (MTF) has been broadly employed to estimate the image quality. Therefore, the objective of this paper is to design and implement an accurate and cost-effective MTF measurement system for the digital camera. Once the MTF of the sensor array is provided, that of the optical module can be then obtained. In this approach, a spatial light modulator (SLM) is employed to modulate the spatial frequency of light emitted from the light-source. The modulated light going through the camera under test is consecutively detected by the sensors. The corresponding images formed from the camera are acquired by a computer and then, they are processed by an algorithm for computing the MTF. Finally, through the investigation on the measurement accuracy from various methods, such as from bar-target and spread-function methods, it appears that our approach gives quite satisfactory results.
EFFECT OF QUALITY OF CHEST RADIOGRAPHS ON THE CATEGORIZATION OF COALWORKERS' PNEUMOCONIOSIS
Pearson, N. G.; Ashford, J. R.; Morgan, D. C.; Pasqual, R. S. H.; Rae, S.
1965-01-01
An investigation into the effect of variations in radiographic technical quality on pneumoconiosis reading standards in the Pneumoconiosis Field Research of the National Coal Board is reported. From the group of men for whom retake films had been obtained because of unsatisfactory technique of the originals, a trial series of pairs and triplets of films showing differing technique was assembled. A total of 778 films was read for pneumoconiosis and assessed for technical quality by four readers. The quality was assessed in terms of three separate factors, viz., density (at high, medium, and low levels), contrast (satisfactory and unsatisfactory), and definition (satisfactory and unsatisfactory). The intra and inter observer consistency of this assessment was estimated, and the effect of techical quality on the reading of pneumoconiosis category was determined. A tendency for lower pneumoconiosis readings to be recorded on films with unsatisfactory technique was demonstrated. A random 10% sample of the best available films (those on which routine pneumoconiosis readings have been made) for all men examined since the beginning of the research was also read for technical quality. Of the total of 4,188 films, 80% were considered satisfactory. It appeared that films taken on second surveys were, in general, of rather better quality than those taken on first surveys. The physical attributes of the men examined had some effect on the technical standards, the proportion of unsatisfactory films rising with increasing values of the weight/sitting height ratio and being greater in men with pneumoconiosis categories 1 and A and in the middle age group. The tendency for lower pneumoconiosis readings to be recorded on films with unsatisfactory technique is in contrast to the results of work previously published. Different criteria for the selection of films and the assessment of technical quality, and possibly differing reading conventions, make comparison with other work difficult. PMID:14278806
Gawroński, Wojciech; Sobiecka, Joanna
2015-11-22
Medical care in disabled sports is crucial both as prophylaxis and as ongoing medical intervention. The aim of this paper was to present changes in the quality of medical care over the consecutive Paralympic Games (PG). The study encompassed 31 paralympians: Turin (11), Vancouver (12), and Sochi (8) competing in cross-country skiing, alpine skiing, biathlon and snowboarding. The first, questionnaire-based, part of the study was conducted in Poland before the PG. The athletes assessed the quality of care provided by physicians, physiologists, dieticians, and physiotherapists, as well as their cooperation with the massage therapist and the psychologist. The other part of the study concerned the athletes' health before leaving for the PG, as well as their diseases and injuries during the PG. The quality of medical care was poor before the 2006 PG, but satisfactory before the subsequent PG. Only few athletes made use of psychological support, assessing it as poor before the 2006 PG and satisfactory before the 2010 and 2014 PG. The athletes' health condition was good during all PG. The health status of cross-country skiers was confirmed by a medical fitness certificate before all PG, while that of alpine skiers only before the 2014 PG. There were no serious diseases; training injuries precluded two athletes from participation. The quality of medical care before the PG was poor, however, became satisfactory during the actual PG. The resulting ad hoc pattern deviates from the accepted standards in medical care in disabled sports.
ERIC Educational Resources Information Center
Department of Education and Science, London (England).
A study investigated techniques and practices for teaching second languages (French, German, Spanish) in 25 urban schools in different areas of England. It was found that the overall quality of work in modern languages was very good in 1 school, good in 5, satisfactory in 7, less than satisfactory in 10, and poor in 2. Three of 10 lessons seen…
Pilot-scale testing membrane bioreactor for wastewater reclamation in industrial laundry.
Andersen, M; Kristensen, G H; Brynjolf, M; Grüttner, H
2002-01-01
A pilot-scale study of membrane bioreactor treatment for reclamation of wastewater from Berendsen Textile Service industrial laundry in Søborg, Denmark was carried out over a 4 month period. A satisfactory COD degradation was performed resulting in a low COD in the permeate (< 50 mg/l). To obtain satisfactory treatment, addition of nitrogen was necessary. The biodegradability of the permeate was very low (BOD5 < 2 mg/l). A hydraulic retention time of 1 d turned out to be sufficient at a sludge concentration of 10 g MLSS/l. Through addition of a cationic polymer, a satisfactory dewaterability of the sludge was reached. Membrane tests showed that operating at a trans-membrane pressure of 3 bar and a cross-flow velocity of 4 m/s, a flux of 120 l/m2h can be expected without using chemicals for membrane cleaning. The quality of the permeate was very good when comparing to the reuse quality demands of water to the wash processes. Reuse of the permeate in all rinsing steps requires additional treatment through reverse osmosis.
Loh, Pui-San; Ariffin, Mohd Azlan; Rai, Vineya; Lai, Lee-Lee; Chan, Lucy; Ramli, Norlisah
2016-11-01
To determine the efficacy of sedation with dexmedetomidine compared to propofol for claustrophobic adults undergoing magnetic resonance imaging (MRI) in our institution. Randomized, prospective, double-blinded study. University-based tertiary referral center. Thirty claustrophobic adults with American Society of Anesthesiologists physical status I and II who were planned for MRI. Patients were randomly assigned to target-controlled infusion propofol or dexmedetomidine loading followed by maintenance dose for procedural sedation. The primary end point was adequate reduction in patient anxiety levels to allow successful completion of the MRI sequence. Both methods of sedation adequately reduced anxiety levels in visual analog scale scores and Spielberger Strait Test Anxiety Inventory (P<.001). Dexmedetomidine required a longer time to achieve anxiolysis, 7.36minutes (SD, 2.59), and required increasing maintenance dose to induce sleep compared to 10.71minutes (SD, 4.63) for propofol. In terms of image quality, 2 patients (16.67%) in the dexmedetomidine group were satisfactory, whereas all with propofol were graded as good to excellent. Adverse effects were seen in patients sedated with dexmedetomidine with number needed to harm 8 for hypotension and 15 for bradycardia compared to none recorded in the propofol arm. There was no significant difference in patient satisfaction scores or home readiness after the MRI. Both dexmedetomidine and propofol can effectively reduce anxiety levels of claustrophobic adults undergoing MRI, but dexmedetomidine takes longer to achieve adequate anxiolysis and sleep and may have an effect on image quality. Hypotension and bradycardia are common adverse effects observed with dexmedetomidine. Copyright © 2016 Elsevier Inc. All rights reserved.
Hershkovitz, Avital; Vesilkov, Marina; Beloosesky, Yichayaou; Brill, Shai
2017-01-10
Total joint arthroplasty (TJA) is an effective and successful treatment of osteoarthritis of the hip and knee as quantified by several measures, such as pain relief, improved walking, improved self-care, functions, and increased quality of life. Data are lacking as to the definition of a satisfactory functional gain in a postacute setting and identifying the characteristics of older patients with TJA who may achieve that gain. Our aim was to characterize patients who may achieve a satisfactory functional gain in a postacute rehabilitation setting following TJA. This was a retrospective study of 180 patients with TJA admitted during 2010-2013. The main outcome measures were the Functional Independence Measure (FIM), the Montebello Rehabilitation Factor Score (MRFS) on the motor FIM, and the Timed Get Up and Go Test. Satisfactory functional gain was defined as an mFIM MRFS score above median score. Comparisons of clinical and demographic characteristics between patients who achieved a satisfactory functional gain versus those who did not were performed by the Mann-Whitney U test and the χ test. The proportion of patients who achieved a satisfactory functional gain was similar in the total knee arthroplasty and total hip arthroplasty (THA) groups. The most significant characteristic of patients who achieved a satisfactory functional gain was their admission functional ability. Age negatively impacted the ability to achieve a satisfactory functional gain in patients with THA. Functional level on admission is the best predictive factor for a better rehabilitation outcome for patients with TJA. Age negatively affects functional gain in patients with THA.
Zhang, Yuyang; Xing, Zhen; She, Dejun; Huang, Nan; Cao, Dairong
2018-01-01
Purpose The aim of this study was to prospectively evaluate the repeatability of non–contrast-enhanced lower-extremity magnetic resonance angiography using the flow-spoiled fresh blood imaging (FS-FBI). Methods Forty-three healthy volunteers and 15 patients with lower-extremity arterial stenosis were recruited in this study and were examined by FS-FBI. Digital subtraction angiography was performed within a week after the FS-FBI in the patient group. Repeatability was assessed by the following parameters: grading of image quality, diameter and area of major arteries, and grading of stenosis of lower-extremity arteries. Two experienced radiologists blinded for patient data independently evaluated the FS-FBI and digital subtraction angiography images. Intraclass correlation coefficients (ICCs), sensitivity, and specificity were used for statistical analysis. Results The grading of image quality of most data was satisfactory. The ICCs for the first and second measures were 0.792 and 0.884 in the femoral segment and 0.803 and 0.796 in the tibiofibular segment for healthy volunteer group, 0.873 and 1.000 in the femoral segment, and 0.737 and 0.737 in the tibiofibular segment for the patient group. Intraobserver and interobserver agreements on diameter and area of arteries were excellent, with ICCs mostly greater than 0.75 in the volunteer group. For stenosis grading analysis, intraobserver ICCs range from 0.784 to 0.862 and from 0.778 to 0.854, respectively. Flow-spoiled fresh blood imaging yielded a mean sensitivity and specificity to detect arterial stenosis or occlusion of 90% and 80% for femoral segment and 86.7% and 93.3% for tibiofibular segment at least. Conclusions Lower-extremity angiography with FS-FBI is a reliable and reproducible screening tool for lower-extremity atherosclerotic disease, especially for patients with impaired renal function. PMID:28787351
Brichtová, Eva; Šenkyřík, J
2017-05-01
A low radiation burden is essential during diagnostic procedures in pediatric patients due to their high tissue sensitivity. Using MR examination instead of the routinely used CT reduces the radiation exposure and the risk of adverse stochastic effects. Our retrospective study evaluated the possibility of using ultrafast single-shot (SSh) sequences and turbo spin echo (TSE) sequences in rapid MR brain imaging in pediatric patients with hydrocephalus and a programmable ventriculoperitoneal drainage system. SSh sequences seem to be suitable for examining pediatric patients due to the speed of using this technique, but significant susceptibility artifacts due to the programmable drainage valve degrade the image quality. Therefore, a rapid MR examination protocol based on TSE sequences, less sensitive to artifacts due to ferromagnetic components, has been developed. Of 61 pediatric patients who were examined using MR and the SSh sequence protocol, a group of 15 patients with hydrocephalus and a programmable drainage system also underwent TSE sequence MR imaging. The susceptibility artifact volume in both rapid MR protocols was evaluated using a semiautomatic volumetry system. A statistically significant decrease in the susceptibility artifact volume has been demonstrated in TSE sequence imaging in comparison with SSh sequences. Using TSE sequences reduced the influence of artifacts from the programmable valve, and the image quality in all cases was rated as excellent. In all patients, rapid MR examinations were performed without any need for intravenous sedation or general anesthesia. Our study results strongly suggest the superiority of the TSE sequence MR protocol compared to the SSh sequence protocol in pediatric patients with a programmable ventriculoperitoneal drainage system due to a significant reduction of susceptibility artifact volume. Both rapid sequence MR protocols provide quick and satisfactory brain imaging with no ionizing radiation and a reduced need for intravenous or general anesthesia.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shukla-Dave, A; Lu, Y; Hatzoglou, V
2014-06-15
Purpose: To investigate the repeatability of reduced field-of-view diffusion-weighted imaging (rFOV DWI) in quantifying apparent diffusion coefficients (ADCs) for human thyroid glands in a clinical setting. Methods: Nine healthy human volunteers were enrolled and underwent 3T MRI exams. For each volunteer, 3 longitudinal exams (2 weeks apart) with 2 repetitive sessions within each exam, including rFOV and conventional full field-of-view (fFOV) DWI scans, were performed. In the acquired DWI images, a fixed-size region of interest (ROI; diameter=8mm) was placed on thyroid glands to calculate ADC. ADC was calculated using a monoexponential function with a noise correction scheme. The repeatability ofmore » ADC was assessed by using coefficient variation (CV) across sessions or exams, which was defined to be: r = 1-CV, 0 < r < 1, where CV=STD/m, STD is the standard deviation of ADC, and m is the average of ADC across sessions or exams. An experienced radiologist assessed and scored rFOV and fFOV DW images based on image characteristics (1, nondiagnostic; 2, poor; 3, satisfactory; 4, good; and 5, excellent).Analysis of variance (ANOVA) was performed to compare ADC values, CV of ADC, repeatability of ADC across sessions and exams, and radiologic scores between rFOV and fFOV DWI techniques. Results: There was no significant difference in ADC values across sessions and exams either in rFOV or fFOV DWI. The average CVs of both rFOV and fFOV DWI were less than 13%. The repeatability of ADC measurement between rFOV and fFOV DWI was not significantly different. The overall image quality was significantly higher with rFOV DWI than with fFOV DWI. Conclusion: This study suggested that ADCs from both rFOV and fFOV DWI were repeatable, but rFOV DWI had superior imaging quality for human thyroid glands in a clinical setting.« less
Haematological validation of a computer-based bone marrow reporting system.
Nguyen, D T; Diamond, L W; Cavenagh, J D; Parameswaran, R; Amess, J A
1997-01-01
AIMS: To prove the safety and effectiveness of "Professor Belmonte", a knowledge-based system for bone marrow reporting, a formal evaluation of the reports generated by the system was performed. METHODS: Three haematologists (a consultant, a senior registrar, and a junior registrar), none of whom were involved in the development of the software, compared the unedited reports generated by Professor Belmonte with the original bone marrow reports in 785 unselected cases. Each haematologist independently graded the quality of Belmonte's reports using one of four categories: (a) better than the original report (more informative, containing useful information missing in the original report); (b) equivalent to the original report; (c) satisfactory, but missing information that should have been included; and (d) unsatisfactory. RESULTS: The consultant graded 64 reports as more informative than the original, 687 as equivalent to the original, 32 as satisfactory, and two as unsatisfactory. The senior registrar considered 29 reports to be better than the original, 739 to be equivalent to the original, 15 to be satisfactory, and two to be unsatisfactory. The junior registrar found that 88 reports were better than the original, 681 were equivalent to the original, 14 were satisfactory, and two were unsatisfactory. Each judge found two different reports to be unsatisfactory according to their criteria. All 785 reports generated by the computer system received at least two scores of satisfactory or better. CONCLUSIONS: In this representative study, Professor Belmonte generated bone marrow reports that proved to be as accurate as the original reports in a large university hospital. The haematology knowledge contained within the system, the reasoning process, and the function of the software are safe and effective for assisting haematologists in generating high quality bone marrow reports. PMID:9215118
Urological diagnosis using clinical PACS
NASA Astrophysics Data System (ADS)
Mills, Stephen F.; Spetz, Kevin S.; Dwyer, Samuel J., III
1995-05-01
Urological diagnosis using fluoroscopy images has traditionally been performed using radiographic films. Images are generally acquired in conjunction with the application of a contrast agent, processed to create analog films, and inspected to ensure satisfactory image quality prior to being provided to a radiologist for reading. In the case of errors the entire process must be repeated. In addition, the radiologist must then often go to a particular reading room, possibly in a remote part of the healthcare facility, to read the images. The integration of digital fluoroscopy modalities with clinical PACS has the potential to significantly improve the urological diagnosis process by providing high-speed access to images at a variety of locations within a healthcare facility without costly film processing. The PACS additionally provides a cost-effective and reliable means of long-term storage and allows several medical users to simultaneously view the same images at different locations. The installation of a digital data interface between the existing clinically operational PACS at the University of Virginia Health Sciences Center and a digital urology fluoroscope is described. Preliminary user interviews that have been conducted to determine the clinical effectiveness of PACS workstations for urological diagnosis are discussed. The specific suitability of the workstation medium is discussed, as are overall advantages and disadvantages of the hardcopy and softcopy media in terms of efficiency, timeliness and cost. Throughput metrics and some specific parameters of gray-scale viewing stations and the expected system impacts resulting from the integration of a urology fluoroscope with PACS are also discussed.
Sensor and Video Monitoring of Water Quality at Bristol Floating Harbour
NASA Astrophysics Data System (ADS)
Chen, Yiheng; Han, Dawei
2017-04-01
Water system is an essential component in a smart city for its sustainability and resilience. The harbourside is a focal area of Bristol with new buildings and features redeveloped in the last ten years, attracting numerous visitors by the diversity of attractions and beautiful views. There is a strong relationship between the satisfactory of the visitors and local people with the water quality in the Harbour. The freshness and beauty of the water body would please people as well as benefit the aquatic ecosystems. As we are entering a data-rich era, this pilot project aims to explore the concept of using video cameras and smart sensors to collect and monitor water quality condition at the Bristol harbourside. The video cameras and smart sensors are connected to the Bristol Is Open network, an open programmable city platform. This will be the first attempt to collect water quality data in real time in the Bristol urban area with the wireless network. The videos and images of the water body collected by the cameras will be correlated with the in-situ water quality parameters for research purposes. The successful implementation of the sensors can attract more academic researchers and industrial partners to expand the sensor network to multiple locations around the city covering the other parts of the Harbour and River Avon, leading to a new generation of urban system infrastructure model.
NASA Astrophysics Data System (ADS)
Prades, Cristina; García-Olmo, Juan; Romero-Prieto, Tomás; García de Ceca, José L.; López-Luque, Rafael
2010-06-01
The procedures used today to characterize cork plank for the manufacture of cork bottle stoppers continue to be based on a traditional, manual method that is highly subjective. Furthermore, there is no specific legislation regarding cork classification. The objective of this viability study is to assess the potential of near-infrared spectroscopy (NIRS) technology for characterizing cork plank according to the following variables: aspect or visual quality, porosity, moisture and geographical origin. In order to calculate the porosity coefficient, an image analysis program was specifically developed in Visual Basic language for a desktop scanner. A set comprising 170 samples from two geographical areas of Andalusia (Spain) was classified into eight quality classes by visual inspection. Spectra were obtained in the transverse and tangential sections of the cork planks using an NIRSystems 6500 SY II reflectance spectrophotometer. The quantitative calibrations showed cross-validation coefficients of determination of 0.47 for visual quality, 0.69 for porosity and 0.66 for moisture. The results obtained using NIRS technology are promising considering the heterogeneity and variability of a natural product such as cork in spite of the fact that the standard error of cross validation (SECV) in the quantitative analysis is greater than the standard error of laboratory (SEL) for the three variables. The qualitative analysis regarding geographical origin achieved very satisfactory results. Applying these methods in industry will permit quality control procedures to be automated, as well as establishing correlations between the different classification systems currently used in the sector. These methods can be implemented in the cork chain of custody certification and will also provide a certainly more objective tool for assessing the economic value of the product.
The Quality of Life of Retired Reengaged Academics in Nigeria
ERIC Educational Resources Information Center
Ejechi, Eucharia Onyema
2012-01-01
The quality of life (QL) of retired academics reengaged in some Nigerian Universities was studied using physical health, subjective happiness, life satisfaction and psychological well-being domains and a measure based on control, autonomy, self-realization and pleasure (CASP) as indicators. Satisfactory QL was indicated all respondents (greater…
7 CFR 58.336 - Frequency of sampling for quality control of cream, butter and related products.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... temperature of 72 °F. to establish and maintain a satisfactory keeping quality history. Optionally 98 °F. for...
Positron emission tomography and optical tissue imaging
Falen, Steven W [Carmichael, CA; Hoefer, Richard A [Newport News, VA; Majewski, Stanislaw [Yorktown, VA; McKisson, John [Hampton, VA; Kross, Brian [Yorktown, VA; Proffitt, James [Newport News, VA; Stolin, Alexander [Newport News, VA; Weisenberger, Andrew G [Yorktown, VA
2012-05-22
A mobile compact imaging system that combines both PET imaging and optical imaging into a single system which can be located in the operating room (OR) and provides faster feedback to determine if a tumor has been fully resected and if there are adequate surgical margins. While final confirmation is obtained from the pathology lab, such a device can reduce the total time necessary for the procedure and the number of iterations required to achieve satisfactory resection of a tumor with good margins.
Classification of human carcinoma cells using multispectral imagery
NASA Astrophysics Data System (ADS)
Ćinar, Umut; Y. Ćetin, Yasemin; Ćetin-Atalay, Rengul; Ćetin, Enis
2016-03-01
In this paper, we present a technique for automatically classifying human carcinoma cell images using textural features. An image dataset containing microscopy biopsy images from different patients for 14 distinct cancer cell line type is studied. The images are captured using a RGB camera attached to an inverted microscopy device. Texture based Gabor features are extracted from multispectral input images. SVM classifier is used to generate a descriptive model for the purpose of cell line classification. The experimental results depict satisfactory performance, and the proposed method is versatile for various microscopy magnification options.
Takemura, Akihiro; Sasamoto, Kouhei; Nakamura, Kaori; Kuroda, Tatsunori; Shoji, Saori; Matsuura, Yukihiro; Matsushita, Tatsuhiko
2013-06-01
In this study, we evaluated the image distortion of three magnetic resonance imaging (MRI) systems with magnetic field strengths of 0.4 T, 1.5 T and 3 T, during stereotactic irradiation of the brain. A quality assurance phantom for MRI image distortion in radiosurgery was used for these measurements of image distortion. Images were obtained from a 0.4-T MRI (APERTO Eterna, HITACHI), a 1.5-T MRI (Signa HDxt, GE Healthcare) and a 3-T MRI (Signa HDx 3.0 T, GE Healthcare) system. Imaging sequences for the 0.4-T and 3-T MRI were based on the 1.5-T MRI sequence used for stereotactic irradiation in the clinical setting. The same phantom was scanned using a computed tomography (CT) system (Aquilion L/B, Toshiba) as the standard. The results showed mean errors in the Z direction to be the least satisfactory of all the directions in all results. The mean error in the Z direction for 1.5-T MRI at -110 mm in the axial plane showed the largest error of 4.0 mm. The maximum errors for the 0.4-T and 3-T MRI were 1.7 mm and 2.8 mm, respectively. The errors in the plane were not uniform and did not show linearity, suggesting that simple distortion correction using outside markers is unlikely to be effective. The 0.4-T MRI showed the lowest image distortion of the three. However, other items, such as image noise, contrast and study duration need to be evaluated in MRI systems when applying frameless stereotactic irradiation.
A Novel Binarization Algorithm for Ballistics Firearm Identification
NASA Astrophysics Data System (ADS)
Li, Dongguang
The identification of ballistics specimens from imaging systems is of paramount importance in criminal investigation. Binarization plays a key role in preprocess of recognizing cartridges in the ballistic imaging systems. Unfortunately, it is very difficult to get the satisfactory binary image using existing binary algorithms. In this paper, we utilize the global and local thresholds to enhance the image binarization. Importantly, we present a novel criterion for effectively detecting edges in the images. Comprehensive experiments have been conducted over sample ballistic images. The empirical results demonstrate the proposed method can provide a better solution than existing binary algorithms.
Gawroński, Wojciech; Sobiecka, Joanna
2015-01-01
Medical care in disabled sports is crucial both as prophylaxis and as ongoing medical intervention. The aim of this paper was to present changes in the quality of medical care over the consecutive Paralympic Games (PG). The study encompassed 31 paralympians: Turin (11), Vancouver (12), and Sochi (8) competing in cross-country skiing, alpine skiing, biathlon and snowboarding. The first, questionnaire-based, part of the study was conducted in Poland before the PG. The athletes assessed the quality of care provided by physicians, physiologists, dieticians, and physiotherapists, as well as their cooperation with the massage therapist and the psychologist. The other part of the study concerned the athletes’ health before leaving for the PG, as well as their diseases and injuries during the PG. The quality of medical care was poor before the 2006 PG, but satisfactory before the subsequent PG. Only few athletes made use of psychological support, assessing it as poor before the 2006 PG and satisfactory before the 2010 and 2014 PG. The athletes’ health condition was good during all PG. The health status of cross-country skiers was confirmed by a medical fitness certificate before all PG, while that of alpine skiers only before the 2014 PG. There were no serious diseases; training injuries precluded two athletes from participation. The quality of medical care before the PG was poor, however, became satisfactory during the actual PG. The resulting ad hoc pattern deviates from the accepted standards in medical care in disabled sports. PMID:26834868
ERIC Educational Resources Information Center
Ishihara-Brito, Reiko
2013-01-01
This paper presents the findings and implications of a qualitative study conducted in Guatemala, which focused on rural, indigenous parents' perceptions of their children's schooling and educational quality. For these parents, the simple fact that their children had improved access to school signifies a satisfactory educational accomplishment;…
Factors Determining e-Learning Service Quality
ERIC Educational Resources Information Center
Uppal, Muhammad Amaad; Ali, Samnan; Gulliver, Stephen R.
2018-01-01
e-Learning courses are fast becoming common-place, yet the success of these online courses varies considerably. Since limited research addresses the issue of e-learning quality (ELQ) of service in higher education environments, there is an increasing need to effectively assess ELQ. In this paper, we argue that to obtain a satisfactory e-learning…
Sub-component modeling for face image reconstruction in video communications
NASA Astrophysics Data System (ADS)
Shiell, Derek J.; Xiao, Jing; Katsaggelos, Aggelos K.
2008-08-01
Emerging communications trends point to streaming video as a new form of content delivery. These systems are implemented over wired systems, such as cable or ethernet, and wireless networks, cell phones, and portable game systems. These communications systems require sophisticated methods of compression and error-resilience encoding to enable communications across band-limited and noisy delivery channels. Additionally, the transmitted video data must be of high enough quality to ensure a satisfactory end-user experience. Traditionally, video compression makes use of temporal and spatial coherence to reduce the information required to represent an image. In many communications systems, the communications channel is characterized by a probabilistic model which describes the capacity or fidelity of the channel. The implication is that information is lost or distorted in the channel, and requires concealment on the receiving end. We demonstrate a generative model based transmission scheme to compress human face images in video, which has the advantages of a potentially higher compression ratio, while maintaining robustness to errors and data corruption. This is accomplished by training an offline face model and using the model to reconstruct face images on the receiving end. We propose a sub-component AAM modeling the appearance of sub-facial components individually, and show face reconstruction results under different types of video degradation using a weighted and non-weighted version of the sub-component AAM.
Surgical treatment of pituitary adenomas using low-field intraoperative magnetic resonance imaging.
Tabakow, Paweł; Czyz, Margin; Jarmundowicz, Włodzimierz; Lechowicz-Głogowska, Ewa
2012-01-01
Intraoperative magnetic resonance imaging (iMRI) is a new technique for imaging of the brain and is used with increasing frequency during neurosurgical operations, enabling the surgeon to make decisions based on real-time images. This paper presents the technique for the surgical treatment of pituitary adenomas using low-field iMRI, evaluates the safety of iMRI usage in pituitary surgery and examines the influence of iMRI on the extent of tumor removal. From October 2008 to December 2010, 18 patients were treated for pituitary adenomas using the low-field iMRI system Polestar N20. The procedures were conducted via the transsphenoidal approach, using the microscopic technique in 15 cases and endoscopically in three cases. The patients' mean age was 56 +/- 15 years; their mean American Society of Anesthesiologists (ASA) score was 2; 67% of them were male. Most of the patients were operated on for macroadenomas, 83% of which were hormonally inactive. The analysis concerned the technical aspects of iMRI usage, such as preparation and surgery time and the quality of the iMRI-scans performed. The safety of iMRI and its influence on decisions regarding further tumor resection. The operations on pituitary adenomas using iMRI were safe. Only two hemorrhagic complications were noted, and they were not related to iMRI usage. The mean preparation and surgery times were 109 +/- 37 minutes and 238 +/- 188 minutes, respectively. The iMRI images of sella turcica were of satisfactory quality in 16 patients. In 50% of the cases, iMRI conducted when the surgeon believed that the desired extent of tumor resection had been attained showed that there were still tumor remnants to be resected. In 67% of these cases, continued tumor removal lead to achievement of the desired degree of resection. Low-field iMRI-guided operations on pituitary tumors are safe and feasible, and they ensure an increased radicality of tumor resection.
González, Jorge Ernesto; Radl, Analía; Romero, Ivonne; Barquinero, Joan Francesc; García, Omar; Di Giorgio, Marina
2016-12-01
Mitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection. Lymphocytes were irradiated and cultured for mitosis detection. Sets of images from cultures were analyzed visually and findings were compared with those using CellProfiler software. The CellProfiler pipeline includes the detection of nuclei and mitosis with 80% sensitivity and more than 99% specificity. We conclude that CellProfiler is a reliable tool for counting mitosis and nuclei from cytogenetic images, saves considerable time compared to manual operation and reduces the variability derived from the scoring criteria of different scorers. The CellProfiler automated pipeline achieves good agreement with visual counting workflow, i.e. it allows fully automated mitotic and nuclei scoring in cytogenetic images yielding reliable information with minimal user intervention. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Kuntoro, Hadiyan Yusuf; Hudaya, Akhmad Zidni; Dinaryanto, Okto; Majid, Akmal Irfan; Deendarlianto
2016-06-01
Due to the importance of the two-phase flow researches for the industrial safety analysis, many researchers developed various methods and techniques to study the two-phase flow phenomena on the industrial cases, such as in the chemical, petroleum and nuclear industries cases. One of the developing methods and techniques is image processing technique. This technique is widely used in the two-phase flow researches due to the non-intrusive capability to process a lot of visualization data which are contain many complexities. Moreover, this technique allows to capture direct-visual information data of the flow which are difficult to be captured by other methods and techniques. The main objective of this paper is to present an improved algorithm of image processing technique from the preceding algorithm for the stratified flow cases. The present algorithm can measure the film thickness (hL) of stratified flow as well as the geometrical properties of the interfacial waves with lower processing time and random-access memory (RAM) usage than the preceding algorithm. Also, the measurement results are aimed to develop a high quality database of stratified flow which is scanty. In the present work, the measurement results had a satisfactory agreement with the previous works.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuntoro, Hadiyan Yusuf, E-mail: hadiyan.y.kuntoro@mail.ugm.ac.id; Majid, Akmal Irfan; Deendarlianto, E-mail: deendarlianto@ugm.ac.id
Due to the importance of the two-phase flow researches for the industrial safety analysis, many researchers developed various methods and techniques to study the two-phase flow phenomena on the industrial cases, such as in the chemical, petroleum and nuclear industries cases. One of the developing methods and techniques is image processing technique. This technique is widely used in the two-phase flow researches due to the non-intrusive capability to process a lot of visualization data which are contain many complexities. Moreover, this technique allows to capture direct-visual information data of the flow which are difficult to be captured by other methodsmore » and techniques. The main objective of this paper is to present an improved algorithm of image processing technique from the preceding algorithm for the stratified flow cases. The present algorithm can measure the film thickness (h{sub L}) of stratified flow as well as the geometrical properties of the interfacial waves with lower processing time and random-access memory (RAM) usage than the preceding algorithm. Also, the measurement results are aimed to develop a high quality database of stratified flow which is scanty. In the present work, the measurement results had a satisfactory agreement with the previous works.« less
Farin, E; Carl, C; Lichtenberg, S; Jäckel, W H; Maier-Riehle, B; Rütten-Köppel, E
2003-12-01
This paper reports the results of a peer review system that was implemented in the context of the quality assurance programme of the statutory German Pension Insurance scheme. The data reported refer to the 2000/2001 data collection period for medical rehabilitation in the somatic indications. Examination of inter-rater reliability for judgements of individual raters shows satisfactory results only in orthopaedics. In the quality assurance programme, rehabilitation centres are usually evaluated by the mean of 20 rater judgements. The reliability of this aggregated measure is satisfactory in all indications. The results of 561 rehabilitation centres show that those quality criteria are in particular need of improvement that refer to subjective concepts of patients (e. g., subjective theories of illness). Between peer review procedures in 1998 and 1999, the quality scores of rehabilitation centres had improved whereas between 1999 and 2000/2001, no further improvement can be shown. However, those rehabilitation centres with a low quality score in 1999 (lowest quartile of the distribution) underwent a positive development between 1999 and 2000/2001. Reasons for this trend and possibilities for improving interrater reliability of the peer review process as an element of the quality assurance programme of the German Pension Insurance scheme are discussed.
Land cover change of watersheds in Southern Guam from 1973 to 2001.
Wen, Yuming; Khosrowpanah, Shahram; Heitz, Leroy
2011-08-01
Land cover change can be caused by human-induced activities and natural forces. Land cover change in watershed level has been a main concern for a long time in the world since watersheds play an important role in our life and environment. This paper is focused on how to apply Landsat Multi-Spectral Scanner (MSS) satellite image of 1973 and Landsat Thematic Mapper (TM) satellite image of 2001 to determine the land cover changes of coastal watersheds from 1973 to 2001. GIS and remote sensing are integrated to derive land cover information from Landsat satellite images of 1973 and 2001. The land cover classification is based on supervised classification method in remote sensing software ERDAS IMAGINE. Historical GIS data is used to replace the areas covered by clouds or shadows in the image of 1973 to improve classification accuracy. Then, temporal land cover is utilized to determine land cover change of coastal watersheds in southern Guam. The overall classification accuracies for Landsat MSS image of 1973 and Landsat TM image of 2001 are 82.74% and 90.42%, respectively. The overall classification of Landsat MSS image is particularly satisfactory considering its coarse spatial resolution and relatively bad data quality because of lots of clouds and shadows in the image. Watershed land cover change in southern Guam is affected greatly by anthropogenic activities. However, natural forces also affect land cover in space and time. Land cover information and change in watersheds can be applied for watershed management and planning, and environmental modeling and assessment. Based on spatio-temporal land cover information, the interaction behavior between human and environment may be evaluated. The findings in this research will be useful to similar research in other tropical islands.
Transparent 3D display for augmented reality
NASA Astrophysics Data System (ADS)
Lee, Byoungho; Hong, Jisoo
2012-11-01
Two types of transparent three-dimensional display systems applicable for the augmented reality are demonstrated. One of them is a head-mounted-display-type implementation which utilizes the principle of the system adopting the concave floating lens to the virtual mode integral imaging. Such configuration has an advantage in that the threedimensional image can be displayed at sufficiently far distance resolving the accommodation conflict with the real world scene. Incorporating the convex half mirror, which shows a partial transparency, instead of the concave floating lens, makes it possible to implement the transparent three-dimensional display system. The other type is the projection-type implementation, which is more appropriate for the general use than the head-mounted-display-type implementation. Its imaging principle is based on the well-known reflection-type integral imaging. We realize the feature of transparent display by imposing the partial transparency to the array of concave mirror which is used for the screen of reflection-type integral imaging. Two types of configurations, relying on incoherent and coherent light sources, are both possible. For the incoherent configuration, we introduce the concave half mirror array, whereas the coherent one adopts the holographic optical element which replicates the functionality of the lenslet array. Though the projection-type implementation is beneficial than the head-mounted-display in principle, the present status of the technical advance of the spatial light modulator still does not provide the satisfactory visual quality of the displayed three-dimensional image. Hence we expect that the head-mounted-display-type and projection-type implementations will come up in the market in sequence.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-05
... improve the quality of product moving from the farm to market, and have helped growers and handlers more effectively market their crops. Additionally, the orders have been used to ensure that only satisfactory quality nectarines and peaches reach the consumer. This has helped increase and maintain market demand...
The quality evaluation of frankfurter-type sausages from hand and mechanically deboned turkey meat.
Radomyski, T; Niewiarowicz, A
1987-03-01
A quality evaluation was made of frankfurter-type sausages made from hand and mechanically deboned meat from various parts of turkey carcasses. The results led to the conclusions that despite some differences in objective measurements of the sausage quality, mechanically deboned turkey meat can be considered as an exclusive meat raw material for the production of frankfurter-type sausages. The quality of sausages from mechanically deboned turkey meat from wings and frames with skin was the least satisfactory.
Cultural Adaptation Quality of Family Life Scale for the Brazilian Portuguese.
Jorge, Bianca Miguel; Levy, Cilmara Cristina Alves da Costa; Granato, Lídio
2015-01-01
To culturally adapt the Family Quality of Life Scale to the Brazilian Portuguese version and evaluate the instrument reliability and family quality of life of those who have children with hearing loss. The process of cultural adaptation of the scale followed the steps of the Guidelines for the Process of Cross-Cultural Adaptation of Self-Report Measure. It was conducted in three stages: translation, back translation, and application in a pilot sample, as a way to check the comprehension difficulties of the items. After it had been completed, it was administered to 41 families who have children with hearing loss and, with their results, the quality of life and reliability were analyzed based on the Cronbach's alpha statistical test. In the first version (translation), among the 25 items, there were differences between the translators only in four items; after the corrections, the second version was done (back translation), in which other four more differences were found. Finally, after the final corrections, the last version was developed and used in the pilot sample without differences. Thus, it was applied to families with deaf children, who believe to be satisfied as to their quality of life. The Cronbach's alpha test found that the scale shows a satisfactory reliability. The Brazilian Portuguese version of the Family Quality of Life Scale is a tool of easy use and satisfactory reliability. The families are satisfied with their family quality of life.
A Robust Zero-Watermarking Algorithm for Audio
NASA Astrophysics Data System (ADS)
Chen, Ning; Zhu, Jie
2007-12-01
In traditional watermarking algorithms, the insertion of watermark into the host signal inevitably introduces some perceptible quality degradation. Another problem is the inherent conflict between imperceptibility and robustness. Zero-watermarking technique can solve these problems successfully. Instead of embedding watermark, the zero-watermarking technique extracts some essential characteristics from the host signal and uses them for watermark detection. However, most of the available zero-watermarking schemes are designed for still image and their robustness is not satisfactory. In this paper, an efficient and robust zero-watermarking technique for audio signal is presented. The multiresolution characteristic of discrete wavelet transform (DWT), the energy compression characteristic of discrete cosine transform (DCT), and the Gaussian noise suppression property of higher-order cumulant are combined to extract essential features from the host audio signal and they are then used for watermark recovery. Simulation results demonstrate the effectiveness of our scheme in terms of inaudibility, detection reliability, and robustness.
Offline Signature Verification Using the Discrete Radon Transform and a Hidden Markov Model
NASA Astrophysics Data System (ADS)
Coetzer, J.; Herbst, B. M.; du Preez, J. A.
2004-12-01
We developed a system that automatically authenticates offline handwritten signatures using the discrete Radon transform (DRT) and a hidden Markov model (HMM). Given the robustness of our algorithm and the fact that only global features are considered, satisfactory results are obtained. Using a database of 924 signatures from 22 writers, our system achieves an equal error rate (EER) of 18% when only high-quality forgeries (skilled forgeries) are considered and an EER of 4.5% in the case of only casual forgeries. These signatures were originally captured offline. Using another database of 4800 signatures from 51 writers, our system achieves an EER of 12.2% when only skilled forgeries are considered. These signatures were originally captured online and then digitally converted into static signature images. These results compare well with the results of other algorithms that consider only global features.
Fruit fly optimization based least square support vector regression for blind image restoration
NASA Astrophysics Data System (ADS)
Zhang, Jiao; Wang, Rui; Li, Junshan; Yang, Yawei
2014-11-01
The goal of image restoration is to reconstruct the original scene from a degraded observation. It is a critical and challenging task in image processing. Classical restorations require explicit knowledge of the point spread function and a description of the noise as priors. However, it is not practical for many real image processing. The recovery processing needs to be a blind image restoration scenario. Since blind deconvolution is an ill-posed problem, many blind restoration methods need to make additional assumptions to construct restrictions. Due to the differences of PSF and noise energy, blurring images can be quite different. It is difficult to achieve a good balance between proper assumption and high restoration quality in blind deconvolution. Recently, machine learning techniques have been applied to blind image restoration. The least square support vector regression (LSSVR) has been proven to offer strong potential in estimating and forecasting issues. Therefore, this paper proposes a LSSVR-based image restoration method. However, selecting the optimal parameters for support vector machine is essential to the training result. As a novel meta-heuristic algorithm, the fruit fly optimization algorithm (FOA) can be used to handle optimization problems, and has the advantages of fast convergence to the global optimal solution. In the proposed method, the training samples are created from a neighborhood in the degraded image to the central pixel in the original image. The mapping between the degraded image and the original image is learned by training LSSVR. The two parameters of LSSVR are optimized though FOA. The fitness function of FOA is calculated by the restoration error function. With the acquired mapping, the degraded image can be recovered. Experimental results show the proposed method can obtain satisfactory restoration effect. Compared with BP neural network regression, SVR method and Lucy-Richardson algorithm, it speeds up the restoration rate and performs better. Both objective and subjective restoration performances are studied in the comparison experiments.
NASA Astrophysics Data System (ADS)
Cuchiara, G. C.; Rappenglück, B.; Rubio, M. A.; Lissi, E.; Gramsch, E.; Garreaud, R. D.
2017-10-01
On January 4, 2014, during the summer period in South America, an intense forest and dry pasture wildfire occurred nearby the city of Santiago de Chile. On that day the biomass-burning plume was transported by low-intensity winds towards the metropolitan area of Santiago and impacted the concentration of pollutants in this region. In this study, the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem) is implemented to investigate the biomass-burning plume associated with these wildfires nearby Santiago, which impacted the ground-level ozone concentration and exacerbated Santiago's air quality. Meteorological variables simulated by WRF/Chem are compared against surface and radiosonde observations, and the results show that the model reproduces fairly well the observed wind speed, wind direction air temperature and relative humidity for the case studied. Based on an analysis of the transport of an inert tracer released over the locations, and at the time the wildfires were captured by the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS), the model reproduced reasonably well the transport of biomass burning plume towards the city of Santiago de Chile within a time delay of two hours as observed in ceilometer data. A six day air quality simulation was performed: the first three days were used to validate the anthropogenic and biogenic emissions, and the last three days (during and after the wildfire event) to analyze the performance of WRF/Chem plume-rise model within FINNv1 fire emission estimations. The model presented a satisfactory performance on the first days of the simulation when contrasted against data from the well-established air quality network over the city of Santiago de Chile. These days represent the urban air quality base case for Santiago de Chile unimpacted by fire emissions. However, for the last three simulation days, which were impacted by the fire emissions, the statistical indices showed a decrease in the model performance. While the model showed a satisfactory evidence that wildfires plumes that originated in the vicinity of Santiago de Chile were transported towards the urban area and impacted the air quality, the model still underpredicted some pollutants substantially, likely due to misrepresentation of fire emission sources during those days. Potential uncertainties may include to the land use/land cover classifications and its characteristics, such as type and density of vegetation assigned to the region, where the fire spots are detected. The variability of the ecosystem type during the fire event might also play a role.
SU-F-I-08: CT Image Ring Artifact Reduction Based On Prior Image
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yuan, C; Qi, H; Chen, Z
Purpose: In computed tomography (CT) system, CT images with ring artifacts will be reconstructed when some adjacent bins of detector don’t work. The ring artifacts severely degrade CT image quality. We present a useful CT ring artifacts reduction based on projection data correction, aiming at estimating the missing data of projection data accurately, thus removing the ring artifacts of CT images. Methods: The method consists of ten steps: 1) Identification of abnormal pixel line in projection sinogram; 2) Linear interpolation within the pixel line of projection sinogram; 3) FBP reconstruction using interpolated projection data; 4) Filtering FBP image using meanmore » filter; 5) Forwarding projection of filtered FBP image; 6) Subtraction forwarded projection from original projection; 7) Linear interpolation of abnormal pixel line area in the subtraction projection; 8) Adding the interpolated subtraction projection on the forwarded projection; 9) FBP reconstruction using corrected projection data; 10) Return to step 4 until the pre-set iteration number is reached. The method is validated on simulated and real data to restore missing projection data and reconstruct ring artifact-free CT images. Results: We have studied impact of amount of dead bins of CT detector on the accuracy of missing data estimation in projection sinogram. For the simulated case with a resolution of 256 by 256 Shepp-Logan phantom, three iterations are sufficient to restore projection data and reconstruct ring artifact-free images when the dead bins rating is under 30%. The dead-bin-induced artifacts are substantially reduced. More iteration number is needed to reconstruct satisfactory images while the rating of dead bins increases. Similar results were found for a real head phantom case. Conclusion: A practical CT image ring artifact correction scheme based on projection data is developed. This method can produce ring artifact-free CT images feasibly and effectively.« less
Preliminary DICOM acceptance testing using the central test node
NASA Astrophysics Data System (ADS)
Chimiak, William J.
1996-05-01
The Bowman Gray School of Medicine of Wake Forest University (BGSM) is installing clinical DICOM workstations and DICOM film digitizers for use in a telemedicine trial over the North Carolina ATM infrastructure. Acquiring equipment thought to be DICOM compliant, but which does not live up to expectations and possibly fails to interoperate with other DICOM equipment, is a concern. In cooperation with RSNA and the Mallinckrodt Institute of Radiology of the Washington University School of Medicine (MIR), BGSM made acceptance of the CEMAX workstations for the telemedicine trial contingent upon a satisfactory test with the MIR central test node (CTN). During the test, both engineers never left their hospitals during the tests drastically cutting travel and per diem costs and valuable time. The successful results exceeded expectations. Images were not only passed back and forth to the CTN by both the CEMAX clinical workstation and the quality assurance workstation, but images arriving from the CTN were entered into the CEMAX clinical database without operator intervention. It was expected that the images would transfer, but the placement into the database, although reasonable to expect, actually occurred. This live test from an independent test source exhibited the ease with which the CEMAX workstations handled the DICOM images in their systems. In the test, the CEMAX workstations were configured as an exporter of DICOM images at BGSM. The CTN was entered in the configuration of the CEMAX workstations as a source of DICOM images. The test was to ensure that plain film, computed tomography, and magnetic resonance images could be easily exchanged between workstations electronically. This paper describes the procedure for using the CTN to provide preliminary testing of DICOM equipment.
NASA Technical Reports Server (NTRS)
Grantham, W. D.; Nguyen, L. T.; Deal, P. L.; Neubauer, M. J.; Smith, P. M.; Gregory, F. D.
1978-01-01
Conventional and powered lift concepts for supersonic approach and landing tasks are considered. Results indicated that the transport concepts had unacceptable low-speed handling qualities with no augmentation, and that in order to achieve satisfactory handling qualities, considerable augmentation was required. The available roll-control power was acceptable for the powered-lift concept.
G. R., Jr. Trimble
1973-01-01
This report is an attempt to integrate and summarize research results from studies made mostly in West Virginia and to show the relationship of site quality and cutting practices to hardwood reproduction, with special emphasis on species composition. Reproduction has been found satisfactory in numbers and distribution after both clearcutting and selection cutting, but...
ERIC Educational Resources Information Center
Kane, Thomas J.; Staiger, Douglas O.
2012-01-01
There is a growing consensus that teacher evaluation in the United States is fundamentally broken. Few would argue that a system that tells 98 percent of teachers they are "satisfactory" benefits anyone--including teachers. The nation's collective failure to invest in high-quality professional feedback to teachers is inconsistent with…
Gobée, O Paul; Jansma, Daniël; DeRuiter, Marco C
2011-10-01
The many synonyms for anatomical structures confuse medical students and complicate medical communication. Easily accessible translations would alleviate this problem. None of the presently available resources-Terminologia Anatomica (TA), digital terminologies such as the Foundational Model of Anatomy (FMA), and websites-are fully satisfactory to this aim. Internet technologies offer new possibilities to solve the problem. Several authors have called for an online TA. An online translation resource should be easily accessible, user-friendly, comprehensive, expandable, and its quality determinable. As first step towards this goal, we built a translation website that we named www.AnatomicalTerms.info, based on the database of the FMA. It translates between English, Latin, eponyms, and to a lesser extent other languages, and presently contains over 31,000 terms for 7,250 structures, covering 95% of TA. In addition, it automatically presents searches for images, documents and anatomical variations regarding the sought structure. Several terminological and conceptual issues were encountered in transferring data from TA and FMA into AnatomicalTerms.info, resultant from these resources' different set-ups (paper versus digital) and targets (machine versus human-user). To the best of our knowledge, AnatomicalTerms.info is unique in its combination of user-friendliness and comprehensiveness. As next step, wiki-like expandability will be added to enable open contribution of clinical synonyms and terms in different languages. Specific quality measures will be taken to strike a balance between open contribution and quality assurance. AnatomicalTerms.info's mechanism that "translates" terms to structures furthermore may enhance targeted searching by linking images, descriptions, and other anatomical resources to the structures. Copyright © 2011 Wiley-Liss, Inc.
Pang, Wai-Man; Qin, Jing; Lu, Yuqiang; Xie, Yongming; Chui, Chee-Kong; Heng, Pheng-Ann
2011-03-01
To accelerate the simultaneous algebraic reconstruction technique (SART) with motion compensation for speedy and quality computed tomography reconstruction by exploiting CUDA-enabled GPU. Two core techniques are proposed to fit SART into the CUDA architecture: (1) a ray-driven projection along with hardware trilinear interpolation, and (2) a voxel-driven back-projection that can avoid redundant computation by combining CUDA shared memory. We utilize the independence of each ray and voxel on both techniques to design CUDA kernel to represent a ray in the projection and a voxel in the back-projection respectively. Thus, significant parallelization and performance boost can be achieved. For motion compensation, we rectify each ray's direction during the projection and back-projection stages based on a known motion vector field. Extensive experiments demonstrate the proposed techniques can provide faster reconstruction without compromising image quality. The process rate is nearly 100 projections s (-1), and it is about 150 times faster than a CPU-based SART. The reconstructed image is compared against ground truth visually and quantitatively by peak signal-to-noise ratio (PSNR) and line profiles. We further evaluate the reconstruction quality using quantitative metrics such as signal-to-noise ratio (SNR) and mean-square-error (MSE). All these reveal that satisfactory results are achieved. The effects of major parameters such as ray sampling interval and relaxation parameter are also investigated by a series of experiments. A simulated dataset is used for testing the effectiveness of our motion compensation technique. The results demonstrate our reconstructed volume can eliminate undesirable artifacts like blurring. Our proposed method has potential to realize instantaneous presentation of 3D CT volume to physicians once the projection data are acquired.
Three-dimensional imaging from a unidirectional hologram: wide-viewing-zone projection type.
Okoshi, T; Oshima, K
1976-04-01
In ordinary holography reconstructing a virtual image, the hologram must be wider than either the visual field or the viewing zone. In this paper, an economical method of recording a wide-viewing-zone wide-visual-field 3-D holographic image is proposed. In this method, many mirrors are used to collect object waves onto a small hologram. In the reconstruction, a real image from the hologram is projected onto a horizontally direction-selective stereoscreen through the same mirrors. In the experiment, satisfactory 3-D images have been observed from a wide viewing zone. The optimum design and information reduction techniques are also discussed.
Super resolution reconstruction of infrared images based on classified dictionary learning
NASA Astrophysics Data System (ADS)
Liu, Fei; Han, Pingli; Wang, Yi; Li, Xuan; Bai, Lu; Shao, Xiaopeng
2018-05-01
Infrared images always suffer from low-resolution problems resulting from limitations of imaging devices. An economical approach to combat this problem involves reconstructing high-resolution images by reasonable methods without updating devices. Inspired by compressed sensing theory, this study presents and demonstrates a Classified Dictionary Learning method to reconstruct high-resolution infrared images. It classifies features of the samples into several reasonable clusters and trained a dictionary pair for each cluster. The optimal pair of dictionaries is chosen for each image reconstruction and therefore, more satisfactory results is achieved without the increase in computational complexity and time cost. Experiments and results demonstrated that it is a viable method for infrared images reconstruction since it improves image resolution and recovers detailed information of targets.
Steidle-Kloc, E; Wirth, W; Ruhdorfer, A; Dannhauer, T; Eckstein, F
2016-03-01
The infra-patellar fat pad (IPFP), as intra-articular adipose tissue represents a potential source of pro-inflammatory cytokines and its size has been suggested to be associated with osteoarthritis (OA) of the knee. This study examines inter- and intra-observer reliability of fat-suppressed (fs) and non-fat-suppressed (nfs) MR imaging for determination of IPFP morphological measurements as novel biomarkers. The IPFP of nine right knees of healthy Osteoarthritis Initiative participants was segmented by five readers, using fs and nfs baseline sagittal MRIs. The intra-observer reliability was determined from baseline and 1-year follow-up images. All segmentations were quality controlled (QC) by an expert reader. Reliability was expressed as root mean square coefficient of variation (RMS CV%). After QC, the inter-observer reliability for fs (nfs) imaging was 2.0% (1.1%) for IPFP volume, 2.1%/2.5% (1.6%/1.8%) for anterior/posterior surface areas, 1.8% (1.8%) for depth, and 2.1% (2.4%) for maximum sagittal area. The intra-observer reliability was 3.1% (5.0%) for volume, 2.3%/2.8% (2.5%/2.9%) for anterior/posterior surfaces, 1.9% (3.5%) for depth, and 3.3% (4.5%) for maximum sagittal area. IPFP volume from nfs images was systematically greater (+7.3%) than from fs images, but highly correlated (r=0.98). The results suggest that quantitative measurements of IPFP morphology can be performed with satisfactory reliability when expert QC is implemented. The IPFP is more clearly depicted in nfs images, and there is a small systematic off-set versus analysis from fs images. However, the high linear relationship between fs and nfs imaging suggests that fs images can be used to analyze IPFP morphology, when nfs images are not available. Copyright © 2015 Elsevier GmbH. All rights reserved.
Intelligent multi-spectral IR image segmentation
NASA Astrophysics Data System (ADS)
Lu, Thomas; Luong, Andrew; Heim, Stephen; Patel, Maharshi; Chen, Kang; Chao, Tien-Hsin; Chow, Edward; Torres, Gilbert
2017-05-01
This article presents a neural network based multi-spectral image segmentation method. A neural network is trained on the selected features of both the objects and background in the longwave (LW) Infrared (IR) images. Multiple iterations of training are performed until the accuracy of the segmentation reaches satisfactory level. The segmentation boundary of the LW image is used to segment the midwave (MW) and shortwave (SW) IR images. A second neural network detects the local discontinuities and refines the accuracy of the local boundaries. This article compares the neural network based segmentation method to the Wavelet-threshold and Grab-Cut methods. Test results have shown increased accuracy and robustness of this segmentation scheme for multi-spectral IR images.
Registration of Heat Capacity Mapping Mission day and night images
NASA Technical Reports Server (NTRS)
Watson, K.; Hummer-Miller, S.; Sawatzky, D. L. (Principal Investigator)
1982-01-01
Neither iterative registration, using drainage intersection maps for control, nor cross correlation techniques were satisfactory in registering day and night HCMM imagery. A procedure was developed which registers the image pairs by selecting control points and mapping the night thermal image to the daytime thermal and reflectance images using an affine transformation on a 1300 by 1100 pixel image. The resulting image registration is accurate to better than two pixels (RMS) and does not exhibit the significant misregistration that was noted in the temperature-difference and thermal-inertia products supplied by NASA. The affine transformation was determined using simple matrix arithmetic, a step that can be performed rapidly on a minicomputer.
On Max-Plus Algebra and Its Application on Image Steganography
Santoso, Kiswara Agung
2018-01-01
We propose a new steganography method to hide an image into another image using matrix multiplication operations on max-plus algebra. This is especially interesting because the matrix used in encoding or information disguises generally has an inverse, whereas matrix multiplication operations in max-plus algebra do not have an inverse. The advantages of this method are the size of the image that can be hidden into the cover image, larger than the previous method. The proposed method has been tested on many secret images, and the results are satisfactory which have a high level of strength and a high level of security and can be used in various operating systems. PMID:29887761
On Max-Plus Algebra and Its Application on Image Steganography.
Santoso, Kiswara Agung; Fatmawati; Suprajitno, Herry
2018-01-01
We propose a new steganography method to hide an image into another image using matrix multiplication operations on max-plus algebra. This is especially interesting because the matrix used in encoding or information disguises generally has an inverse, whereas matrix multiplication operations in max-plus algebra do not have an inverse. The advantages of this method are the size of the image that can be hidden into the cover image, larger than the previous method. The proposed method has been tested on many secret images, and the results are satisfactory which have a high level of strength and a high level of security and can be used in various operating systems.
Computer method for identification of boiler transfer functions
NASA Technical Reports Server (NTRS)
Miles, J. H.
1972-01-01
Iterative computer aided procedure was developed which provides for identification of boiler transfer functions using frequency response data. Method uses frequency response data to obtain satisfactory transfer function for both high and low vapor exit quality data.
Development of an aerial counting system in oil palm plantations
NASA Astrophysics Data System (ADS)
Zulyma Miserque Castillo, Jhany; Laverde Diaz, Rubbermaid; Rueda Guzmán, Claudia Leonor
2016-07-01
This paper proposes the development of a counting aerial system capable of capturing, process and analyzing images of an oil palm plantation to register the number of cultivated palms. It begins with a study of the available UAV technologies to define the most appropriate model according to the project needs. As result, a DJI Phantom 2 Vision+ is used to capture pictures that are processed by a photogrammetry software to create orthomosaics from the areas of interest, which are handled by the developed software to calculate the number of palms contained in them. The implemented algorithm uses a sliding window technique in image pyramids to generate candidate windows, an LBP descriptor to model the texture of the picture, a logistic regression model to classify the windows and a non-maximum suppression algorithm to refine the decision. The system was tested in different images than the ones used for training and for establishing the set point. As result, the system showed a 95.34% detection rate with a 97.83% precision in mature palms and a 79.26% detection rate with a 97.53% precision in young palms giving an FI score of 0.97 for mature palms and 0.87 for the small ones. The results are satisfactory getting the census and high-quality images from which is possible to get more information from the area of interest. All this, achieved through a low-cost system capable of work even in cloudy conditions.
Clinical efficacy of telemedicine in emergency radiotherapy for malignant spinal cord compression.
Hashimoto, S; Shirato, H; Kaneko, K; Ooshio, W; Nishioka, T; Miyasaka, K
2001-09-01
The authors developed a Telecommunication-HElped Radiotherapy Planning and Information SysTem (THERAPIST), then estimated its clinical benefit in radiotherapy in district hospitals where consultation with the university hospital was required. The system consists of a personal computer with an image scanner and a digital camera, set up in district hospitals and directly connected via ISDN to an image server, and a treatment planning device set up in a university hospital. Image data and consultative reports are sent to the server. Radiation oncologists at the university hospital determine a treatment schedule and verify actual treatment fields. From 1998 to 1999, 12 patients with malignant spinal cord compression (MSCC) were treated by emergency radiotherapy with the help of this system. Image quality, transmission time, and cost benefit also were satisfactory for clinical use. The mean time between the onset of symptoms and the start of radiotherapy was reduced significantly from 7.1 days to 0.8 days (P < .05) by the introduction of the system. Five of 6 nonambulant patients became ambulant after the introduction of THERAPIST compared with 2 of 8 before the introduction of THERAPIST. The treatment outcome was significantly better after the introduction of the system (P < .05), and suggested to be beyond the international standard. The telecommunication-helped radiotherapy and information system was useful in emergency radiotherapy in district hospitals for patients with MSCC for whom consultation with experienced radiation oncologists at a university hospital was required.
Minkin, Krasimir; Gabrovski, Kaloyan; Penkov, Marin; Todorov, Yuri; Tanova, Rositsa; Milenova, Yoana; Romansky, Kiril; Dimova, Petia
2017-10-01
Stereoelectroencephalography (SEEG) requires high-quality angiographic studies because avascular trajectory planning is a prerequisite for the safety of this procedure. Some epilepsy surgery groups have begun to use computed tomography angiography and magnetic resonance T1-weighted sequence with contrast enhancement for this purpose. To present the first series of patients with avascular trajectory planning of SEEG based on magnetic resonance angiography (MRA). Thirty-six SEEG explorations for drug-resistant focal epilepsy were performed from January 2013 to December 2015. A retrospective analysis of this consecutive surgical series was then performed. Magnetic resonance imaging included MRA with a modified contrast-enhanced magnetic resonance venography (MRV) protocol with a short acquisition delay, which allowed simultaneous arterial and venous visualization. Our criteria for satisfactory MRA were the visualization of at least first-order branches of the angular artery, paracentral and calcarine artery, and third-order tributaries of the superficial Sylvian vein, vein of Labbe, and vein of Trolard. Thirty-four patients underwent 36 SEEG explorations with 369 electrodes carrying 4321 contacts. Contrast-enhanced MRA using the MRV protocol was judged satisfactory for SEEG planning in all explorations. Postoperative complications were not observed in our series of 36 SEEG explorations, which included 50 transopercular insular trajectories. MRA using an MRV protocol may be applied for avascular trajectory planning during SEEG procedures. This technique provides a simultaneous visualization of cortical arteries and veins without the need for additional radiation exposure or intra-arterial catheter placement. Copyright © 2017 by the Congress of Neurological Surgeons
Negative Stains Containing Trehalose: Application to Tubular and Filamentous Structures
NASA Astrophysics Data System (ADS)
Harris, J. Robin; Gerber, Max; Gebauer, Wolfgang; Wernicke, Wolfgang; Markl, Jürgen
1996-02-01
Several examples are presented that show the successful application of uranyl acetate and ammonium molybdate negative staining in the presence of trehalose for TEM studies of filamentous and tubular structures. The principal benefit to be gained from the inclusion of trehalose stems from the considerably reduced flattening of the large tubular structures and the greater orientational freedom of single molecules due to an increased depth of the negative stain in the presence of trehalose. Trehalose is likely to provide considerable protection to protein molecules and their assemblies during the drying of negatively stained specimens. Some reduction in the excessive density imparted by uranyl acetate around large assemblies is also achieved. Nevertheless, in the presence of 1% (w/v) trehalose, it is desirable to increase the concentration of negative stain to 5% (w/v) for ammonium molybdate and to 4% for uranyl acetate to produce satisfactory image contrast. In general, the ammonium molybdate-trehalose negative stain is more satisfactory than the uranyl acetate-trehalose combination, because of the greater electron beam sensitivity of the uranyl negative stain. Reassembled taxol-stabilized pig brain microtubules, together with collagen fibrils, sperm tails, helical filaments, and reassociated hemocyanin (KLH2), all from the giant keyhole limpet Megathura crenulata, have been studied by negative staining in the presence of trehalose. In all cases satisfactory TEM imaging conditions were readily obtained on the specimens, as long as regions of excessively deep stain were avoided.
Flight test and analyses of the B-1 structural mode control system at supersonic flight conditions
NASA Technical Reports Server (NTRS)
Wykes, J. H.; Kelpl, M. J.; Brosnan, M. J.
1983-01-01
A practical structural mode control system (SMCS) that could be turned on at takeoff and be left on for the entire flight was demonstrated. The SMCS appears to be more effective in damping the key fuselage bending modes at supersonic speeds than at the design point of Mach 0.85 (for fixed gains). The SMCS has an adverse effect on high frequency symmetric modes; however, this adverse effect did not make the system unstable and does not appear to affect ride quality performance. The vertical ride quality analyses indicate that the basic configuration without active systems is satisfactory for long term exposure. If clear air turbulence were to be encountered, indications are that the SMCS would be very effective in reducing the adverse accelerations. On the other hand, lateral ride quality analyses indicate that the aircraft with the SMCS on does not quite meet the long term exposure criteria, but would be satisfactory for shot term exposure at altitude. Again, the lateral SMCS was shown to be very effective in reducing peak lateral accelerations.
Effects of physiotherapy treatment for urinary incontinence in patient with multiple sclerosis.
Pereira, Carla Maria de Abreu; Castiglione, Mariane; Kasawara, Karina Tamy
2017-07-01
[Purpose] The aim of the study was to evaluate the benefits of physical therapy for urinary incontinence in patients with multiple sclerosis and to verify the impact of urinary incontinence on the patient's quality of life. [Subject and Methods] A case study of a 55-year-old female patient diagnosed with multiple sclerosis and mixed urinary incontinence was conducted. Physical therapy sessions were conducted once a week, in total 15 sessions, making use of targeted functional electrical vaginal stimulation, along with active exercises for the pelvic floor muscles and electrical stimulation of the posterior tibial nerve, behavioral rehabilitation and exercise at home. [Results] After 15 physical therapy sessions, a patient diagnosed with multiple sclerosis and mixed urinary incontinence showed continued satisfactory results after five months. She showed better quality of life, higher strength of pelvic floor muscle and reduced urinary frequency without nocturia and enuresis. [Conclusion] The physical therapy protocol in this patient with multiple sclerosis and mixed urinary incontinence showed satisfactory results reducing urinary incontinence symptomatology and improving the patient's quality of life.
Howat, William J; Blows, Fiona M; Provenzano, Elena; Brook, Mark N; Morris, Lorna; Gazinska, Patrycja; Johnson, Nicola; McDuffus, Leigh‐Anne; Miller, Jodi; Sawyer, Elinor J; Pinder, Sarah; van Deurzen, Carolien H M; Jones, Louise; Sironen, Reijo; Visscher, Daniel; Caldas, Carlos; Daley, Frances; Coulson, Penny; Broeks, Annegien; Sanders, Joyce; Wesseling, Jelle; Nevanlinna, Heli; Fagerholm, Rainer; Blomqvist, Carl; Heikkilä, Päivi; Ali, H Raza; Dawson, Sarah‐Jane; Figueroa, Jonine; Lissowska, Jolanta; Brinton, Louise; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli‐Matti; Cox, Angela; Brock, Ian W; Cross, Simon S; Reed, Malcolm W; Couch, Fergus J; Olson, Janet E; Devillee, Peter; Mesker, Wilma E; Seyaneve, Caroline M; Hollestelle, Antoinette; Benitez, Javier; Perez, Jose Ignacio Arias; Menéndez, Primitiva; Bolla, Manjeet K; Easton, Douglas F; Schmidt, Marjanka K; Pharoah, Paul D; Sherman, Mark E
2014-01-01
Abstract Breast cancer risk factors and clinical outcomes vary by tumour marker expression. However, individual studies often lack the power required to assess these relationships, and large‐scale analyses are limited by the need for high throughput, standardized scoring methods. To address these limitations, we assessed whether automated image analysis of immunohistochemically stained tissue microarrays can permit rapid, standardized scoring of tumour markers from multiple studies. Tissue microarray sections prepared in nine studies containing 20 263 cores from 8267 breast cancers stained for two nuclear (oestrogen receptor, progesterone receptor), two membranous (human epidermal growth factor receptor 2 and epidermal growth factor receptor) and one cytoplasmic (cytokeratin 5/6) marker were scanned as digital images. Automated algorithms were used to score markers in tumour cells using the Ariol system. We compared automated scores against visual reads, and their associations with breast cancer survival. Approximately 65–70% of tissue microarray cores were satisfactory for scoring. Among satisfactory cores, agreement between dichotomous automated and visual scores was highest for oestrogen receptor (Kappa = 0.76), followed by human epidermal growth factor receptor 2 (Kappa = 0.69) and progesterone receptor (Kappa = 0.67). Automated quantitative scores for these markers were associated with hazard ratios for breast cancer mortality in a dose‐response manner. Considering visual scores of epidermal growth factor receptor or cytokeratin 5/6 as the reference, automated scoring achieved excellent negative predictive value (96–98%), but yielded many false positives (positive predictive value = 30–32%). For all markers, we observed substantial heterogeneity in automated scoring performance across tissue microarrays. Automated analysis is a potentially useful tool for large‐scale, quantitative scoring of immunohistochemically stained tissue microarrays available in consortia. However, continued optimization, rigorous marker‐specific quality control measures and standardization of tissue microarray designs, staining and scoring protocols is needed to enhance results. PMID:27499890
Sensory and rapid instrumental methods as a combined tool for quality control of cooked ham.
Barbieri, Sara; Soglia, Francesca; Palagano, Rosa; Tesini, Federica; Bendini, Alessandra; Petracci, Massimiliano; Cavani, Claudio; Gallina Toschi, Tullia
2016-11-01
In this preliminary investigation, different commercial categories of Italian cooked pork hams have been characterized using an integrated approach based on both sensory and fast instrumental measurements. For these purposes, Italian products belonging to different categories (cooked ham, "selected" cooked ham and "high quality" cooked ham) were evaluated by sensory descriptive analysis and by the application of rapid tools such as image analysis by an "electronic eye" and texture analyzer. The panel of trained assessors identified and evaluated 10 sensory descriptors able to define the quality of the products. Statistical analysis highlighted that sensory characteristics related to appearance and texture were the most significant in discriminating samples belonged to the highest (high quality cooked hams) and the lowest (cooked hams) quality of the product whereas the selected cooked hams, showed intermediate characteristics. In particular, high quality samples were characterized, above all, by the highest intensity of pink intensity, typical appearance and cohesiveness, and, at the same time, by the lowest intensity of juiciness; standard cooked ham samples showed the lowest intensity of all visual attributes and the highest value of juiciness, whereas the intermediate category (selected cooked ham) was not discriminated from the other. Also physical-rheological parameters measured by electronic eye and texture analyzer were effective in classifying samples. In particular, the PLS model built with data obtained from the electronic eye showed a satisfactory performance in terms of prediction of the pink intensity and presence of fat attributes evaluated during the sensory visual phase. This study can be considered a first application of this combined approach that could represent a suitable and fast method to verify if the meat product purchased by consumer match its description in terms of compliance with the claimed quality.
Steidle-Kloc, E.; Wirth, W.; Ruhdorfer, A.; Dannhauer, T.; Eckstein, F.
2015-01-01
The infra-patellar fat pad (IPFP), as intra-articular adipose tissue represents a potential source of pro-inflammatory cytokines and its size has been suggested to be associated with osteoarthritis (OA) of the knee. This study examines inter- and intra-observer reliability of fat-suppressed (fs) and non-fat-suppressed (nfs) MR imaging for determination of IPFP morphological measurements as novel biomarkers. The IPFP of nine right knees of healthy Osteoarthritis Initiative participants was segmented by five readers, using fs and nfs baseline sagittal MRIs. The intra-observer reliability was determined from baseline and 1-year follow-up images. All segmentations were quality controlled (QC) by an expert reader. Reliability was expressed as root mean square coefficient of variation (RMS CV%). After QC, the inter-observer reliability for fs (nfs) imaging was 2.0% (1.1%) for IPFP volume, 2.1%/2.5% (1.6%/1.8%) for anterior/posterior surface areas, 1.8% (1.8%) for depth, and 2.1% (2.4%) for maximum sagittal area. The intra-observer reliability was 3.1% (5.0%) for volume, 2.3%/2.8% (2.5%/2.9%) for anterior/posterior surfaces, 1.9% (3.5%) for depth, and 3.3% (4.5%) for maximum sagittal area. IPFP volume from nfs images was systematically greater (+7.3%) than from fs images, but highly correlated (r = 0.98). The results suggest that quantitative measurements of IPFP morphology can be performed with satisfactory reliability when expert QC is implemented. The IPFP is more clearly depicted in nfs images, and there is a small systematic off-set versus analysis from fs images. However, the high linear relationship between fs and nfs imaging suggests that fs images can be used to analyze IPFP morphology, when nfs images are not available. PMID:26569532
Baños-Capilla, M C; García, M A; Bea, J; Pla, C; Larrea, L; López, E
2007-06-01
The quality of dosimetry in radiotherapy treatment requires the accurate delimitation of the gross tumor volume. This can be achieved by complementing the anatomical detail provided by CT images through fusion with other imaging modalities that provide additional metabolic and physiological information. Therefore, use of multiple imaging modalities for radiotherapy treatment planning requires an accurate image registration method. This work describes tests carried out on a Discovery LS positron emission/computed tomography (PET/CT) system by General Electric Medical Systems (GEMS), for its later use to obtain images to delimit the target in radiotherapy treatment. Several phantoms have been used to verify image correlation, in combination with fiducial markers, which were used as a system of external landmarks. We analyzed the geometrical accuracy of two different fusion methods with the images obtained with these phantoms. We first studied the fusion method used by the PET/CT system by GEMS (hardware fusion) on the basis that there is satisfactory coincidence between the reconstruction centers in CT and PET systems; and secondly the fiducial fusion, a registration method, by means of least-squares fitting algorithm of a landmark points system. The study concluded with the verification of the centroid position of some phantom components in both imaging modalities. Centroids were estimated through a calculation similar to center-of-mass, weighted by the value of the CT number and the uptake intensity in PET. The mean deviations found for the hardware fusion method were: deltax/ +/-sigma = 3.3 mm +/- 1.0 mm and /deltax/ +/-sigma = 3.6 mm +/- 1.0 mm. These values were substantially improved upon applying fiducial fusion based on external landmark points: /deltax/ +/-sigma = 0.7 mm +/- 0.8 mm and /deltax/ +/-sigma = 0.3 mm 1.7 mm. We also noted that differences found for each of the fusion methods were similar for both the axial and helical CT image acquisition protocols.
7 CFR 58.336 - Frequency of sampling for quality control of cream, butter and related products.
Code of Federal Regulations, 2012 CFR
2012-01-01
... or modified Kohman test may be used. (c) Chemical—(1) Acid degree value. This test should be made on... lipase activity. (2) Free fatty acid. This test should be made on churnings or batches from samples taken... temperature of 72 °F. to establish and maintain a satisfactory keeping quality history. Optionally 98 °F. for...
7 CFR 58.336 - Frequency of sampling for quality control of cream, butter and related products.
Code of Federal Regulations, 2011 CFR
2011-01-01
... or modified Kohman test may be used. (c) Chemical—(1) Acid degree value. This test should be made on... lipase activity. (2) Free fatty acid. This test should be made on churnings or batches from samples taken... temperature of 72 °F. to establish and maintain a satisfactory keeping quality history. Optionally 98 °F. for...
7 CFR 58.336 - Frequency of sampling for quality control of cream, butter and related products.
Code of Federal Regulations, 2013 CFR
2013-01-01
... or modified Kohman test may be used. (c) Chemical—(1) Acid degree value. This test should be made on... lipase activity. (2) Free fatty acid. This test should be made on churnings or batches from samples taken... temperature of 72 °F. to establish and maintain a satisfactory keeping quality history. Optionally 98 °F. for...
7 CFR 58.336 - Frequency of sampling for quality control of cream, butter and related products.
Code of Federal Regulations, 2014 CFR
2014-01-01
... or modified Kohman test may be used. (c) Chemical—(1) Acid degree value. This test should be made on... lipase activity. (2) Free fatty acid. This test should be made on churnings or batches from samples taken... temperature of 72 °F. to establish and maintain a satisfactory keeping quality history. Optionally 98 °F. for...
Parkinsonism after glycine-derivate exposure.
Barbosa, E R; Leiros da Costa, M D; Bacheschi, L A; Scaff, M; Leite, C C
2001-05-01
This 54-year-old man accidentally sprayed himself with the chemical agent glyphosate, a herbicide derived from the amino acid glycine. He developed disseminated skin lesions 6 hours after the accident. One month later, he developed a symmetrical parkinsonian syndrome. Two years after the initial exposure to glyphosate, magnetic resonance imaging revealed hyperintense signal in the globus pallidus and substantia nigra, bilaterally, on T2-weighted images. Levodopa/benserazide 500/125 mg daily provided satisfactory clinical outcome.
A Low-Cost Tele-Imaging Platform for Developing Countries
Adambounou, Kokou; Adjenou, Victor; Salam, Alex P.; Farin, Fabien; N’Dakena, Koffi Gilbert; Gbeassor, Messanvi; Arbeille, Philippe
2014-01-01
Purpose: To design a “low-cost” tele-imaging method allowing real-time tele-ultrasound expertise, delayed tele-ultrasound diagnosis, and tele-radiology between remote peripherals hospitals and clinics (patient centers) and university hospital centers (expert center). Materials and methods: A system of communication via internet (IP camera and remote access software) enabling transfer of ultrasound videos and images between two centers allows a real-time tele-radiology expertise in the presence of a junior sonographer or radiologist at the patient center. In the absence of a sonographer or radiologist at the patient center, a 3D reconstruction program allows a delayed tele-ultrasound diagnosis with images acquired by a lay operator (e.g., midwife, nurse, technician). The system was tested both with high and low bandwidth. The system can further accommodate non-ultrasound tele-radiology (conventional radiography, mammography, and computer tomography for example). The system was tested on 50 patients between CHR Tsevie in Togo (40 km from Lomé-Togo and 4500 km from Tours-France) and CHU Campus at Lomé and CHU Trousseau in Tours. Results: A real-time tele-expertise was successfully performed with a delay of approximately 1.5 s with an internet bandwidth of around 1 Mbps (IP Camera) and 512 kbps (remote access software). A delayed tele-ultrasound diagnosis was also performed with satisfactory results. The transmission of radiological images from the patient center to the expert center was of adequate quality. Delayed tele-ultrasound and tele-radiology was possible even in the presence of a low-bandwidth internet connection. Conclusion: This tele-imaging method, requiring nothing by readily available and inexpensive technology and equipment, offers a major opportunity for telemedicine in developing countries. PMID:25250306
Statistical Validation of Image Segmentation Quality Based on a Spatial Overlap Index1
Zou, Kelly H.; Warfield, Simon K.; Bharatha, Aditya; Tempany, Clare M.C.; Kaus, Michael R.; Haker, Steven J.; Wells, William M.; Jolesz, Ferenc A.; Kikinis, Ron
2005-01-01
Rationale and Objectives To examine a statistical validation method based on the spatial overlap between two sets of segmentations of the same anatomy. Materials and Methods The Dice similarity coefficient (DSC) was used as a statistical validation metric to evaluate the performance of both the reproducibility of manual segmentations and the spatial overlap accuracy of automated probabilistic fractional segmentation of MR images, illustrated on two clinical examples. Example 1: 10 consecutive cases of prostate brachytherapy patients underwent both preoperative 1.5T and intraoperative 0.5T MR imaging. For each case, 5 repeated manual segmentations of the prostate peripheral zone were performed separately on preoperative and on intraoperative images. Example 2: A semi-automated probabilistic fractional segmentation algorithm was applied to MR imaging of 9 cases with 3 types of brain tumors. DSC values were computed and logit-transformed values were compared in the mean with the analysis of variance (ANOVA). Results Example 1: The mean DSCs of 0.883 (range, 0.876–0.893) with 1.5T preoperative MRI and 0.838 (range, 0.819–0.852) with 0.5T intraoperative MRI (P < .001) were within and at the margin of the range of good reproducibility, respectively. Example 2: Wide ranges of DSC were observed in brain tumor segmentations: Meningiomas (0.519–0.893), astrocytomas (0.487–0.972), and other mixed gliomas (0.490–0.899). Conclusion The DSC value is a simple and useful summary measure of spatial overlap, which can be applied to studies of reproducibility and accuracy in image segmentation. We observed generally satisfactory but variable validation results in two clinical applications. This metric may be adapted for similar validation tasks. PMID:14974593
Three-layered radio frequency coil arrangement for sodium MRI of the human brain at 9.4 Tesla.
Shajan, G; Mirkes, Christian; Buckenmaier, Kai; Hoffmann, Jens; Pohmann, Rolf; Scheffler, Klaus
2016-02-01
A multinuclei imaging setup with the capability to acquire both sodium ((23) Na) and proton ((1) H) signals at 9.4 Tesla is presented. The main objective was to optimize coil performance at the (23) Na frequency while still having the ability to acquire satisfactory (1) H images. The setup consisted of a combination of three radio frequency (RF) coils arranged in three layers: the innermost layer was a 27-channel (23) Na receive helmet which was surrounded by a four-channel (23) Na transceiver array. The outer layer consisted of a four-channel (1) H dipole array for B0 shimming and anatomical localization. Transmit and receive performance of the (23) Na arrays was compared to a single-tuned (23) Na birdcage resonator. While the transmit efficiency of the (23) Na transceiver array was comparable to the birdcage, the (23) Na receive array provided substantial signal-to-noise ratio (SNR) gain near the surface and comparable SNR in the center. The utility of this customized setup was demonstrated by (23) Na images of excellent quality. High SNR, efficient transmit excitation and B0 shimming capability can be achieved for (23) Na MRI at 9.4T using novel coil combination. This RF configuration is easily adaptable to other multinuclei applications at ultra high field (≥ 7T). © 2015 Wiley Periodicals, Inc.
Mc Laughlin, Patrick; Neill, Siobhan O; Fanning, Noel; Mc Garrigle, Anne Marie; Connor, Owen J O; Wyse, Gerry; Maher, Michael M
2012-04-01
Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.
Liu, Jiaen; Zhang, Xiaotong; Schmitter, Sebastian; Van de Moortele, Pierre-Francois; He, Bin
2014-01-01
Purpose To develop high-resolution electrical properties tomography (EPT) methods and investigate a gradient-based EPT (gEPT) approach which aims to reconstruct the electrical properties (EP), including conductivity and permittivity, of an imaged sample from experimentally measured B1 maps with improved boundary reconstruction and robustness against measurement noise. Theory and Methods Using a multi-channel transmit/receive stripline head coil, with acquired B1 maps for each coil element, by assuming negligible Bz component compared to transverse B1 components, a theory describing the relationship between B1 field, EP value and their spatial gradient has been proposed. The final EP images were obtained through spatial integration over the reconstructed EP gradient. Numerical simulation, physical phantom and in vivo human experiments at 7 T have been conducted to evaluate the performance of the proposed methods. Results Reconstruction results were compared with target EP values in both simulations and phantom experiments. Human experimental results were compared with EP values in literature. Satisfactory agreement was observed with improved boundary reconstruction. Importantly, the proposed gEPT method proved to be more robust against noise when compared to previously described non-gradient-based EPT approaches. Conclusion The proposed gEPT approach holds promises to improve EP mapping quality by recovering the boundary information and enhancing robustness against noise. PMID:25213371
Real-time image mosaicing for medical applications.
Loewke, Kevin E; Camarillo, David B; Jobst, Christopher A; Salisbury, J Kenneth
2007-01-01
In this paper we describe the development of a robotically-assisted image mosaicing system for medical applications. The processing occurs in real-time due to a fast initial image alignment provided by robotic position sensing. Near-field imaging, defined by relatively large camera motion, requires translations as well as pan and tilt orientations to be measured. To capture these measurements we use 5-d.o.f. sensing along with a hand-eye calibration to account for sensor offset. This sensor-based approach speeds up the mosaicing, eliminates cumulative errors, and readily handles arbitrary camera motions. Our results have produced visually satisfactory mosaics on a dental model but can be extended to other medical images.
Quality of life for patients living with ostomies: influence of contact with an ostomy nurse.
Aronovitch, Sharon A; Sharp, Robbie; Harduar-Morano, Laurel
2010-01-01
This study was conducted to determine whether or not contact with a WOC nurse improves quality of life for ostomy patients. Home health care agencies, hospitals, and a durable medical equipment company in northern Florida were contacted to participate in the study. The role of the participating facilities was to address the provided envelopes and mail the patient survey packet (introductory letter, Ostomy Quality of Life Questionnaire [OQLQ], and demographic survey) directly to the patient. The mean age or respondents was 62 years, and the mean time of living with an ostomy was 10 years. Ninety-six percent of the sample participants did not attend support groups, yet nearly 50% reported receiving education following discharge home. Analysis of OQLQ scores revealed statistically significant differences based on who the respondent lived with, the number of comorbidities, how the respondent received supplies, and the type of appliance worn. There was no significant difference between respondents who saw an ostomy nurse and those who did not among the various sections of the OQLQ, even though 83% indicated seeing an ostomy nurse. Body image was a concern to respondents. The data demonstrated that most participants maintained satisfactory quality of life despite the presence of an ostomy. Individuals who were working part-time had a better health-related quality of life than those who worked full-time. More than 50% of our study sample participants reported satisfaction with the healthcare services they received, regardless of whether services were provided by a WOC or a nonspecialist nurse.
Registration of 'Prevail' hard red spring wheat
USDA-ARS?s Scientific Manuscript database
Grower and end-user acceptance of new Hard Red Spring Wheat (HRSW; Triticum aestivum L.) cultivars is largely contingent upon satisfactory agronomic performance, end-use quality potential, and disease resistance levels. Additional characteristics, such as desirable plant height, can also contribute...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-29
... States in sufficient and reasonably available quantities and of a satisfactory quality), with respect to...) Thermostatic Regulator Valves that regulate the flow of hot water or low pressure steam through free-standing...
Fingerprint image enhancement by differential hysteresis processing.
Blotta, Eduardo; Moler, Emilce
2004-05-10
A new method to enhance defective fingerprints images through image digital processing tools is presented in this work. When the fingerprints have been taken without any care, blurred and in some cases mostly illegible, as in the case presented here, their classification and comparison becomes nearly impossible. A combination of spatial domain filters, including a technique called differential hysteresis processing (DHP), is applied to improve these kind of images. This set of filtering methods proved to be satisfactory in a wide range of cases by uncovering hidden details that helped to identify persons. Dactyloscopy experts from Policia Federal Argentina and the EAAF have validated these results.
Processing urinary endoscopes in a low-temperature steam and formaldehyde autoclave.
Gibson, G L
1977-01-01
Methods of disinfection and sterilisation of urinary endoscopes are considered. A small mobile low-temperature steam and formaldehyde autoclave (Miniclave 80) is evaluated and shown to be satisfactory for this purpose as judged by a variety of relevant microbiological test pieces. Images PMID:557503
NASA Technical Reports Server (NTRS)
Anderson, Seth B.; Cooper, George E.
1947-01-01
This report contains the flight-test results of the stalling characteristics measured during the flying-qualities investigation of the Lockheed P-8OA airplane (Army No. 44-85099). The tests were conducted in straight and turning flight with and without wing-tip tanks. These tests showed satisfactory stalling characteristics and adequate stall warning for all configurations and conditions tested.
Crowhurst, James A; Poon, Karl K; Murdoch, Dale; Incani, Alexander; Raffel, Owen C; Liddicoat, Annelise; Walters, Darren
2015-12-01
Profiling the Aortic root perpendicular to the fluoroscopic image plane will achieve a more successful implant position for trans-catheter aortic valve replacement (TAVR). This study aimed to investigate whether the divergent nature of the X-ray beam from the C-arm altered the appearance of the TAVR device. Under bench-top testing, a 23, 26 and 29 mm Edwards Sapien XT valve was positioned coaxially at the bottom of a fluoroscopic image utilising 22 and 32 cm fields of view (FOV). The table was then moved so that the valve was positioned at the top of the image. The valve's appearance was scored using a previously published three tier classification tool (excellent, satisfactory and poor) and quantified with measurements. The number of degrees of C-arm rotation that were required to bring the valve back to a coaxial appearance was recorded. When using the 32 cm FOV, the valve's appearance changes from excellent to satisfactory. When a 22 cm FOV was used, the change is less marked. More C-arm rotation is required to bring the appearance back to coaxial with the 32 cm FOV. Not maintaining the valve in the centre of the image can distort the valves appearance. This has the potential to affect the final implantation depth.
NASA Astrophysics Data System (ADS)
Zhao, Cong; Zhong, Yuncheng; Duan, Xinhui; Zhang, You; Huang, Xiaokun; Wang, Jing; Jin, Mingwu
2018-06-01
Four-dimensional (4D) x-ray cone-beam computed tomography (CBCT) is important for a precise radiation therapy for lung cancer. Due to the repeated use and 4D acquisition over a course of radiotherapy, the radiation dose becomes a concern. Meanwhile, the scatter contamination in CBCT deteriorates image quality for treatment tasks. In this work, we propose the use of a moving blocker (MB) during the 4D CBCT acquisition (‘4D MB’) and to combine motion-compensated reconstruction to address these two issues simultaneously. In 4D MB CBCT, the moving blocker reduces the x-ray flux passing through the patient and collects the scatter information in the blocked region at the same time. The scatter signal is estimated from the blocked region for correction. Even though the number of projection views and projection data in each view are not complete for conventional reconstruction, 4D reconstruction with a total-variation (TV) constraint and a motion-compensated temporal constraint can utilize both spatial gradient sparsity and temporal correlations among different phases to overcome the missing data problem. The feasibility simulation studies using the 4D NCAT phantom showed that 4D MB with motion-compensated reconstruction with 1/3 imaging dose reduction could produce satisfactory images and achieve 37% improvement on structural similarity (SSIM) index and 55% improvement on root mean square error (RMSE), compared to 4D reconstruction at the regular imaging dose without scatter correction. For the same 4D MB data, 4D reconstruction outperformed 3D TV reconstruction by 28% on SSIM and 34% on RMSE. A study of synthetic patient data also demonstrated the potential of 4D MB to reduce the radiation dose by 1/3 without compromising the image quality. This work paves the way for more comprehensive studies to investigate the dose reduction limit offered by this novel 4D MB method using physical phantom experiments and real patient data based on clinical relevant metrics.
Zhao, Cong; Zhong, Yuncheng; Duan, Xinhui; Zhang, You; Huang, Xiaokun; Wang, Jing; Jin, Mingwu
2018-05-03
Four-dimensional (4D) X-ray cone-beam computed tomography (CBCT) is important for a precise radiation therapy for lung cancer. Due to the repeated use and 4D acquisition over a course of radiotherapy, the radiation dose becomes a concern. Meanwhile, the scatter contamination in CBCT deteriorates image quality for treatment tasks. In this work, we propose to use a moving blocker (MB) during the 4D CBCT acquisition ("4D MB") and to combine motion-compensated reconstruction to address these two issues simultaneously. In 4D MB CBCT, the moving blocker reduces the X-ray flux passing through the patient and collects the scatter information in the blocked region at the same time. The scatter signal is estimated from the blocked region for correction. Even though the number of projection views and projection data in each view are not complete for conventional reconstruction, 4D reconstruction with a total-variation (TV) constraint and a motion-compensated temporal constraint can utilize both spatial gradient sparsity and temporal correlations among different phases to overcome the missing data problem. The feasibility simulation studies using the 4D NCAT phantom showed that 4D MB with motion-compensated reconstruction with 1/3 imaging dose reduction could produce satisfactory images and achieve 37% improvement on structural similarity (SSIM) index and 55% improvement on root mean square error (RMSE), compared to 4D reconstruction at the regular imaging dose without scatter correction. For the same 4D MB data, 4D reconstruction outperformed 3D TV reconstruction by 28% on SSIM and 34% on RMSE. A study of synthetic patient data also demonstrated the potential of 4D MB to reduce the radiation dose by 1/3 without compromising the image quality. This work paves the way for more comprehensive studies to investigate the dose reduction limit offered by this novel 4D MB method using physical phantom experiments and real patient data based on clinical relevant metrics. © 2018 Institute of Physics and Engineering in Medicine.
Quality of environmental impact statements and variability of scrutiny by reviewers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, Kaja, E-mail: kaja.peterson@seit.e
2010-04-15
Adequate provision of information is essential for decision making. This paper provides the results of the quality assessment of Environmental Impact Statements (EIS), documents prescribed by EIA Directive (337/85/EEC). The assessment was completed by several categories of reviewers in Estonia, which has been an EU member state since 2004. The quality assessment of EIS was based on the EC Guidance on EIS Review (2001). Firstly, the quality assessment of 50 randomly selected EIS was carried out by a single reviewer. Secondly, the individual grading among 24 independent reviewers of a single EIS was tested. Thirdly, a comparison of the resultsmore » of 15 individual and 5 group assessments of the same EIS was conducted. The results from the quality assessment of the selected EIS demonstrate a satisfactory level of information provided for decision making; 68% of the sample EIS were positively graded. However, more than half of the 50 EIS were graded as 'just satisfactory'. Comparison between the individual and group assessment of the same EIS demonstrates that the group assessment is more critical than the individual assessment. This possibly results from a wider technical expertise and balancing of subjective values and perspectives among group members. Arguably, the current practice of EIA competent authorities assessing the quality of EIS with individuals could be revised. We discuss the effect of the group assessment on expanding the narrow technical expertise and the subjectivity of a single expert.« less
Roy, Alexis T; Penninger, Richard T; Pearl, Monica S; Wuerfel, Waldemar; Jiradejvong, Patpong; Carver, Courtney; Buechner, Andreas; Limb, Charles J
2016-02-01
Cochlear implant (CI) electrode arrays typically do not reach the most apical regions of the cochlea that intrinsically encode low frequencies. This may contribute to diminished implant-mediated musical sound quality perception. The objective of this study was to assess the effect of varying degrees of apical cochlear stimulation (measured by angular insertion depth) on musical sound quality discrimination. Increased apical cochlear stimulation will improve low-frequency perception and musical sound quality discrimination. Standard (31.5 mm, n = 17) and medium (24 mm, n = 8) array Med-EL CI users, and normal hearing (NH) listeners (n = 16) participated. Imaging confirmed angular insertion depth. Participants completed a musical discrimination task in which they listened to a real-world musical stimulus (labeled reference) and provided sound quality ratings to versions of the reference, which included a hidden reference and test stimuli with increasing amounts of low-frequency removal. Scores for each CI users were calculated on the basis of how much their ratings differed from NH listeners for each stimulus version. Medium array and standard users had significantly different insertion depths (389.4 ± 64.5 and 583.9 ± 78.5 degrees, respectively; p < .001). A significant Pearson's correlation was observed between angular insertion depth and the hidden reference scores (p < 0.05). CI users with greater apical stimulation made sound quality discriminations that more closely resembled those of NH controls for stimuli that contained low frequencies (< 200 Hz of information). These findings suggest that increased apical cochlear stimulation improves musical low-frequency perception, which may provide a more satisfactory music listening experience for CI users.
Kołłątaj, Barbara; Kołłątaj, Witold; Wrzołek, Katarzyna; Karwat, Irena Dorota; Klatka, Maria
2017-03-31
Introduction. The quality of primary medical care for children in Poland is unsatisfactory. In the ranking known as 'the European Health Consumer Index', Poland (taking the patient point of view on healthcare quality) is classified on the 27th position out of the 33 possible. The unsolved problems concern inter alia the quality and availability of night paediatric urgent care. The aim was assessing the quality as well as the level of satisfaction with the night paediatric urgent care in the Lublin Province of eastern Poland. The materials for this study consisted of 540 parents of children aged 6-16 years benefiting from night paediatric urgent medical assistance in Lublin Province. The survey was conducted using the Original Survey Questionnaire. Inhabitants of the Lublin Province (regardless of place of residence) generally assessed the quality and accessibility of night paediatric urgent care facilities as only satisfactory. Inhabitants living in rural areas have worse access to night paediatric urgent care facilities because of having to travel greater distances, and receive less comprehensive medical assistance than inhabitants living in more urbanized areas, and they are more often referred to hospital emergency departments. During the past five years, both the availability and quality of night paediatric urgent care did not change significantly. Inhabitants of the Lublin Province (regardless of place of residence) generally assessed the quality as well as accessibility of night paediatric urgent care facilities as only satisfactory. Rural residents have more reasons for dissatisfaction than urban dwellers. Both the quality and availability of such medical care needs to be improved.
NASA Technical Reports Server (NTRS)
Biezad, Daniel
1997-01-01
Handling qualities analysis and control law design would seem to be naturally complimenting components of aircraft flight control system design, however these two closely coupled disciplines are often not well integrated in practice. Handling qualities engineers and control system engineers may work in separate groups within an aircraft company. Flight control system engineers and handling quality specialists may come from different backgrounds and schooling and are often not aware of the other group's research. Thus while the handling qualities specifications represent desired aircraft response characteristics, these are rarely incorporated directly in the control system design process. Instead modem control system design techniques are based on servo-loop robustness specifications, and simple representations of the desired control response. Comprehensive handling qualities analysis is often left until the end of the design cycle and performed as a check of the completed design for satisfactory performance. This can lead to costly redesign or less than satisfactory aircraft handling qualities when the flight testing phase is reached. The desire to integrate the fields of handling qualities and flight,control systems led to the development of the CONDUIT system. This tool facilitates control system designs that achieve desired handling quality requirements and servo-loop specifications in a single design process. With CONDUIT, the control system engineer is now able to directly design and control systems to meet the complete handling specifications. CONDUIT allows the designer to retain a preferred control law structure, but then tunes the system parameters to meet the handling quality requirements.
Whitehead, William E; Palsson, Olafur S; Levy, Rona L; Feld, Andrew D; VonKorff, Michael; Turner, Marsha
2006-05-01
Treatment trials for irritable bowel syndrome (IBS) usually define a responder as a patient who reports satisfactory relief or adequate relief of symptoms at the end of the trial. However, these measures have not been adequately validated. (1) Compare a binary satisfactory relief measure to alternative ways of defining a treatment responder. (2) Determine whether baseline IBS symptom severity or psychological distress influence the sensitivity of these outcome measures. A total of 350 patients (81% females, average age 50 yr) who had a medical diagnosis of IBS and satisfied Rome II criteria, were recruited from Group Health Cooperative of Puget Sound. At baseline the Irritable Bowel Severity Scale (IBSS) was used to assess symptom severity and to classify patients as mild, moderate, or severe. Psychological distress and IBS-specific quality of life (IBS-QOL) were also assessed. After 6 months treatment with standard medical care, IBSS and IBS-QOL were reassessed, and patients were asked whether they had experienced satisfactory relief and whether they were somewhat or markedly better. Initial severity of IBS significantly affected the proportion who reported satisfactory relief (mild, 72%; moderate, 53%; severe, 44%) and the proportion who were somewhat or markedly better (mild, 62%; moderate, 44%; severe, 38%), but did not affect the proportion with a 50% reduction in symptoms (mild, 26%; moderate, 25%; severe, 23%). Although mild patients were the most likely to report satisfactory relief, they showed no average decrease in symptom severity or improvement in IBS-QOL. Conversely, severe patients, who were the least likely to report satisfactory relief, had the largest reductions in IBS symptom severity and the largest improvements in IBS-QOL. Psychological distress had no significant effect on the responder rate after adjusting for IBS symptom severity. These data from a descriptive study suggest that satisfactory relief is confounded with initial IBS symptom severity and is poorly correlated with the amount of symptom improvement. Confirmation of these findings in a clinical trial is needed.
Object tracking using plenoptic image sequences
NASA Astrophysics Data System (ADS)
Kim, Jae Woo; Bae, Seong-Joon; Park, Seongjin; Kim, Do Hyung
2017-05-01
Object tracking is a very important problem in computer vision research. Among the difficulties of object tracking, partial occlusion problem is one of the most serious and challenging problems. To address the problem, we proposed novel approaches to object tracking on plenoptic image sequences. Our approaches take advantage of the refocusing capability that plenoptic images provide. Our approaches input the sequences of focal stacks constructed from plenoptic image sequences. The proposed image selection algorithms select the sequence of optimal images that can maximize the tracking accuracy from the sequence of focal stacks. Focus measure approach and confidence measure approach were proposed for image selection and both of the approaches were validated by the experiments using thirteen plenoptic image sequences that include heavily occluded target objects. The experimental results showed that the proposed approaches were satisfactory comparing to the conventional 2D object tracking algorithms.
Surgical management of spinal intramedullary tumors: radical and safe strategy for benign tumors.
Takami, Toshihiro; Naito, Kentaro; Yamagata, Toru; Ohata, Kenji
2015-01-01
Surgery for spinal intramedullary tumors remains one of the major challenges for neurosurgeons, due to their relative infrequency, unknown natural history, and surgical difficulty. We are sure that safe and precise resection of spinal intramedullary tumors, particularly encapsulated benign tumors, can result in acceptable or satisfactory postoperative outcomes. General surgical concepts and strategies, technical consideration, and functional outcomes after surgery are discussed with illustrative cases of spinal intramedullary benign tumors such as ependymoma, cavernous malformation, and hemangioblastoma. Selection of a posterior median sulcus, posterolateral sulcus, or direct transpial approach was determined based on the preoperative imaging diagnosis and careful inspection of the spinal cord surface. Tumor-cord interface was meticulously delineated in cases of benign encapsulated tumors. Our retrospective functional analysis of 24 consecutive cases of spinal intramedullary ependymoma followed for at least 6 months postoperatively demonstrated a mean grade on the modified McCormick functional schema of 1.8 before surgery, deteriorating significantly to 2.6 early after surgery (< 1 month after surgery), and finally returning to 1.7 in the late postoperative period (> 6 months after surgery). The risk of functional deterioration after surgery should be taken into serious consideration. Functional deterioration after surgery, including neuropathic pain even long after surgery, significantly affects patient quality of life. Better balance between tumor control and functional preservation can be achieved not only by the surgical technique or expertise, but also by intraoperative neurophysiological monitoring, vascular image guidance, and postoperative supportive care. Quality of life after surgery should inarguably be given top priority.
Prada, F; Del Bene, M; Mattei, L; Lodigiani, L; DeBeni, S; Kolev, V; Vetrano, I; Solbiati, L; Sakas, G; DiMeco, F
2015-04-01
Brain shift and tissue deformation during surgery for intracranial lesions are the main actual limitations of neuro-navigation (NN), which currently relies mainly on preoperative imaging. Ultrasound (US), being a real-time imaging modality, is becoming progressively more widespread during neurosurgical procedures, but most neurosurgeons, trained on axial computed tomography (CT) and magnetic resonance imaging (MRI) slices, lack specific US training and have difficulties recognizing anatomic structures with the same confidence as in preoperative imaging. Therefore real-time intraoperative fusion imaging (FI) between preoperative imaging and intraoperative ultrasound (ioUS) for virtual navigation (VN) is highly desirable. We describe our procedure for real-time navigation during surgery for different cerebral lesions. We performed fusion imaging with virtual navigation for patients undergoing surgery for brain lesion removal using an ultrasound-based real-time neuro-navigation system that fuses intraoperative cerebral ultrasound with preoperative MRI and simultaneously displays an MRI slice coplanar to an ioUS image. 58 patients underwent surgery at our institution for intracranial lesion removal with image guidance using a US system equipped with fusion imaging for neuro-navigation. In all cases the initial (external) registration error obtained by the corresponding anatomical landmark procedure was below 2 mm and the craniotomy was correctly placed. The transdural window gave satisfactory US image quality and the lesion was always detectable and measurable on both axes. Brain shift/deformation correction has been successfully employed in 42 cases to restore the co-registration during surgery. The accuracy of ioUS/MRI fusion/overlapping was confirmed intraoperatively under direct visualization of anatomic landmarks and the error was < 3 mm in all cases (100 %). Neuro-navigation using intraoperative US integrated with preoperative MRI is reliable, accurate and user-friendly. Moreover, the adjustments are very helpful in correcting brain shift and tissue distortion. This integrated system allows true real-time feedback during surgery and is less expensive and time-consuming than other intraoperative imaging techniques, offering high precision and orientation. © Georg Thieme Verlag KG Stuttgart · New York.
Speckle Tracking Imaging in Normal Stress Echocardiography.
Leitman, Marina; Tyomkin, Vladimir; Peleg, Eli; Zyssman, Izhak; Rosenblatt, Simcha; Sucher, Edgar; Gercenshtein, Vered; Vered, Zvi
2017-04-01
Exercise stress echocardiography is a widely used modality for the diagnosis and follow-up of patients with coronary artery disease. During the last decade, speckle tracking imaging has been used increasingly for accurate evaluation of cardiac function. This work aimed to assess speckle-tracking imaging parameters during nonischemic exercise stress echocardiography. During 2011 to 2014 we studied 46 patients without history of coronary artery disease, who completed exercise stress echocardiography protocol, had normal left ventricular function, a nonischemic response, and satisfactory image quality. These exams were analyzed with speckle-tracking imaging software at rest and at peak exercise. Peak strain and time-to-peak strain were measured at rest and after exercise. Clinical follow-up included a telephone contact 1 to 3 years after stress echo exam, confirming freedom from coronary events during this time. Global and regional peak strain increased following exercise. Time-to-peak global and regional strain and time-to-peak strain adjusted to the heart rate were significantly shorter in all segments after exercise. Rest-to-stress ratio of time-to-peak strain adjusted to the heart rate was 2.0 to 2.8. Global and regional peak strain rise during normal exercise echocardiography. Peak global and regional strain occur before or shortly after aortic valve closure at rest and after exercise, and the delay is more apparent at the basal segments. Time-to-peak strain normally shortens significantly during exercise; after adjustment to heart rate it shortens by a ratio of 2.0 to 2.8. These data may be useful for interpretation of future exercise stress speckle-tracking echocardiography studies. © 2016 by the American Institute of Ultrasound in Medicine.
[The Brazilian Hospital Information System and the acute myocardial infarction hospital care].
Escosteguy, Claudia Caminha; Portela, Margareth Crisóstomo; Medronho, Roberto de Andrade; de Vasconcellos, Maurício Teixeira Leite
2002-08-01
To analyze the applicability of the Brazilian Unified Health System's national hospital database to evaluate the quality of acute myocardial infarction hospital care. It was evaluated 1,936 hospital admission forms having acute myocardial infarction (AMI) as primary diagnosis in the municipal district of Rio de Janeiro, Brazil, in 1997. Data was collected from the national hospital database. A stratified random sampling of 391 medical records was also evaluated. AMI diagnosis agreement followed the literature criteria. Variable accuracy analysis was performed using kappa index agreement. The quality of AMI diagnosis registered in hospital admission forms was satisfactory according to the gold standard of the literature. In general, the accuracy of the variables demographics (sex, age group), process (medical procedures and interventions), and outcome (hospital death) was satisfactory. The accuracy of demographics and outcome variables was higher than the one of process variables. Under registration of secondary diagnosis was high in the forms and it was the main limiting factor. Given the study findings and the widespread availability of the national hospital database, it is pertinent its use as an instrument in the evaluation of the quality of AMI medical care.
Image-based automatic recognition of larvae
NASA Astrophysics Data System (ADS)
Sang, Ru; Yu, Guiying; Fan, Weijun; Guo, Tiantai
2010-08-01
As the main objects, imagoes have been researched in quarantine pest recognition in these days. However, pests in their larval stage are latent, and the larvae spread abroad much easily with the circulation of agricultural and forest products. It is presented in this paper that, as the new research objects, larvae are recognized by means of machine vision, image processing and pattern recognition. More visional information is reserved and the recognition rate is improved as color image segmentation is applied to images of larvae. Along with the characteristics of affine invariance, perspective invariance and brightness invariance, scale invariant feature transform (SIFT) is adopted for the feature extraction. The neural network algorithm is utilized for pattern recognition, and the automatic identification of larvae images is successfully achieved with satisfactory results.
American Association of Dental Schools Curricular Guidelines for Oral Radiology.
ERIC Educational Resources Information Center
Journal of Dental Education, 1980
1980-01-01
Oral radiology curricular guidelines developed by the American Association of Dental Schools are provided. The guidelines describe minimal conditions under which a satisfactory educational experience can be offered. Principles of x-radiation, radiobiological concepts, radiological health, radiographic technique, radiographic quality, and darkroom…
1961-01-11
3/4 FRONT VIEW OF HILLER H-23C (USA 56-2288). USE OF THE HILLER H-23 HELICOPTER AS AN AID IN ESTABLISHING SATISFACTORY FLYING QUALITIES & REQUIREMENTS FOR VTOL AIRCRAFT. Rotocraft Research. NASA SP Flight Research at Ames: 57 Years of Development and Validation of Aeronautical Technology
Performance and quality-control standards for composite floor, wall, and truss framing
Gerald A. Koenigshof
1985-01-01
Users must be assured that composite structural members are satisfactory for their intended purposes. Standards are provided for strength, stiffness, durability, and dimensional stability of composite floor, wall, and truss-framing members. Methods for enforcing compliance with the standards are suggested.
NASA Astrophysics Data System (ADS)
Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.
2017-07-01
X-ray micro- and nanotomography has evolved into a quantitative analysis tool rather than a mere qualitative visualization technique for the study of porous natural materials. Tomographic reconstructions are subject to noise that has to be handled by image filters prior to quantitative analysis. Typically, denoising filters are designed to handle random noise, such as Gaussian or Poisson noise. In tomographic reconstructions, noise has been projected from Radon space to Euclidean space, i.e. post reconstruction noise cannot be expected to be random but to be correlated. Reconstruction artefacts, such as streak or ring artefacts, aggravate the filtering process so algorithms performing well with random noise are not guaranteed to provide satisfactory results for X-ray tomography reconstructions. With sufficient image resolution, the crystalline origin of most geomaterials results in tomography images of objects that are untextured. We developed a denoising framework for these kinds of samples that combines a noise level estimate with iterative nonlocal means denoising. This allows splitting the denoising task into several weak denoising subtasks where the later filtering steps provide a controlled level of texture removal. We describe a hands-on explanation for the use of this iterative denoising approach and the validity and quality of the image enhancement filter was evaluated in a benchmarking experiment with noise footprints of a varying level of correlation and residual artefacts. They were extracted from real tomography reconstructions. We found that our denoising solutions were superior to other denoising algorithms, over a broad range of contrast-to-noise ratios on artificial piecewise constant signals.
Sequential and simultaneous SLAR block adjustment. [spline function analysis for mapping
NASA Technical Reports Server (NTRS)
Leberl, F.
1975-01-01
Two sequential methods of planimetric SLAR (Side Looking Airborne Radar) block adjustment, with and without splines, and three simultaneous methods based on the principles of least squares are evaluated. A limited experiment with simulated SLAR images indicates that sequential block formation with splines followed by external interpolative adjustment is superior to the simultaneous methods such as planimetric block adjustment with similarity transformations. The use of the sequential block formation is recommended, since it represents an inexpensive tool for satisfactory point determination from SLAR images.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Higashi, T.; Osada, T.; Aoyama, W.
A new dental x-ray fluorographic unit has been developed. This unit is composed of small intraoral x-ray tube, a compact x-ray image intensifier, and a high-resolution TV system. The purposes for developing this equipment were to (1) directly observe the tooth during endodontic procedures and (2) reduce x-ray exposure to the patient and the dentist. The radiation exposure can be reduced to about 1/600 the exposure used with conventional dental film. In clinical trials, a satisfactory fluorographic dental image for endodontic treatment was obtained with this new device.
XUV coherent diffraction imaging in reflection geometry with low numerical aperture.
Zürch, Michael; Kern, Christian; Spielmann, Christian
2013-09-09
We present an experimental realization of coherent diffraction imaging in reflection geometry illuminating the sample with a laser driven high harmonic generation (HHG) based XUV source. After recording the diffraction pattern in reflection geometry, the data must be corrected before the image can be reconstructed with a hybrid-input-output (HIO) algorithm. In this paper we present a detailed investigation of sources of spoiling the reconstructed image due to the nonlinear momentum transfer, errors in estimating the angle of incidence on the sample, and distortions by placing the image off center in the computation grid. Finally we provide guidelines for the necessary parameters to realize a satisfactory reconstruction within a spatial resolution in the range of one micron for an imaging scheme with a numerical aperture NA < 0.03.
A study of atmospheric effects on pattern recognition devices. [Sacramento Valley, California
NASA Technical Reports Server (NTRS)
Thomson, F. J. (Principal Investigator); Sadowski, F. G.
1975-01-01
The author has identified the following significant results. ERTS-1 imagery can be applied in the broadscale assessment of forest resources as a supplement to aerial photography and field survey. There was no application to inventory of crop and pasture diseases mainly because of poor quality and low resolution, and unreliability of image acquisition. Inventory of soil erosion was satisfactory in humid eastern New South Wales, but not in semi-arid areas. Patterns of snow cover, areas of water in natural and artificial water bodies, extent of bushfires, and location of coastal mobile sand bodies were readily apparent. ERTS-1 imagery was judged to be a valuable addition to conventional techniques of regional small scale geological mapping. ERTS data was successfully used to map flooding and flood progression. The imagery was found suitable for mapping at 1:1,000,000 scale both on the mainland and in Antarctica, but did not meet accuracy specifications for 1:250,000 mapping.
Results of a one-day, descriptive study of quality of life in patients with chronic wounds.
Shukla, Vijay K; Shukla, Dinesh; Tripathi, Anuj K; Agrawal, Saurabh; Tiwary, Satyendra K; Prakash, Vivek
2008-05-01
Quality of life is a subjectively interpreted phenomenon that can be profoundly altered by the presence of a wound. Particularly when complete and expedient healing seems unrealistic, quality of life becomes the focus of care. To assess the influence of a variety of chronic wounds on patient quality of life, a 1-day, descriptive study was conducted among 50 consecutive outpatients (64% men, 36% women; age range 14 to 78 years) with chronic wounds who attended the Wound Clinic of the University Hospital, Varanasi, India. A quality-of-life questionnaire containing six parameters (physical activities, feelings, household duties, leisure time activities, social relations, and general activities) was developed and administered. Demographic information was available as a result of a previous study at this institution. Quality-of-life scores were grouped as satisfactory and unsatisfactory and participants were grouped by age (<30 years old, 30 to 60 years old, >60 years old). Wounds were classified by cause (diabetes, venous disease, pressure ulcer, and tuberculosis) and size (<10 cm2, 10 to 50 cm2, >50 cm2). The most common site was the lower limb or foot (39, 78%), followed by upper limb (six, 12%) and head, neck, and trunk (five, 10%). More than half (28, 56%) of all patients had an unsatisfactory overall quality-of-life score. The percentage of patients with satisfactory scores was higher in patients with smaller versus larger wounds and wounds located on upper rather than lower limbs, as well as in middle-aged versus younger or older patients. This patient-centered instrument helped document important quality-of-life concerns among chronic wound patients.
Processing Pipeline of Sugarcane Spectral Response to Characterize the Fallen Plants Phenomenon
NASA Astrophysics Data System (ADS)
Solano, Agustín; Kemerer, Alejandra; Hadad, Alejandro
2016-04-01
Nowadays, in agronomic systems it is possible to make a variable management of inputs to improve the efficiency of agronomic industry and optimize the logistics of the harvesting process. In this way, it was proposed for sugarcane culture the use of remote sensing tools and computational methods to identify useful areas in the cultivated lands. The objective was to use these areas to make variable management of the crop. When at the moment of harvesting the sugarcane there are fallen stalks, together with them some strange material (vegetal or mineral) is collected. This strange material is not millable and when it enters onto the sugar mill it causes important looses of efficiency in the sugar extraction processes and affects its quality. Considering this issue, the spectral response of sugarcane plants in aerial multispectral images was studied. The spectral response was analyzed in different bands of the electromagnetic spectrum. Then, the aerial images were segmented to obtain homogeneous regions useful for producers to make decisions related to the use of inputs and resources according to the variability of the system (existence of fallen cane and standing cane). The obtained segmentation results were satisfactory. It was possible to identify regions with fallen cane and regions with standing cane with high precision rates.
Code of Federal Regulations, 2010 CFR
2010-01-01
... of equipment. Culinary steam used in direct contact with milk or dairy products shall be free from... used wherever applicable to insure a satisfactory and safe steam supply. Culinary steam shall comply with the 3-A Accepted Practices for a Method of Producing Steam of Culinary Quality, number 609. This...
The trophic classification of lakes using ERTS multispectral scanner data
NASA Technical Reports Server (NTRS)
Blackwell, R. J.; Boland, D. H.
1975-01-01
Lake classification methods based on the use of ERTS data are described. Preliminary classification results obtained by multispectral and digital image processing techniques indicate satisfactory correlation between ERTS data and EPA-supplied water analysis. Techniques for determining lake trophic levels using ERTS data are examined, and data obtained for 20 lakes are discussed.
Human Dignity Through the American Experience. (Government). Grade 12.
ERIC Educational Resources Information Center
Vallejo Unified School District, CA.
The curriculum guide for twelfth grade pupils aims at helping students to understand and accept people who are different, develop a satisfactory self image, learn to think critically in the decision making process, and become familiar with the valuing process. Information on foundations in American government serves as a base for human rights and…
Wetting behaviors of phenol- and urea-formaldehyde resins as compatiblizers
Sangyeob Lee; Todd F. Shupe; Leslie H. Groom; Chung Y. Hse
2006-01-01
Understanding wetting behavior and surface coverage of resins on a wood surface is important to obtain satisfactory adhesion and optimize adhesive application for wood composite manufacturing. Sessile and micro-droplets of urea- and phenol-formaldehyde (UF and PF) resins were generated on wood surfaces to observe wetting behaviors using three directional image...
Ivanovic, Jugoslav; Larsson, Pål G; Østby, Ylva; Hald, John; Krossnes, Bård K; Fjeld, Jan G; Pripp, Are H; Alfstad, Kristin Å; Egge, Arild; Stanisic, Milo
2017-05-01
Seizure outcome following surgery in pharmacoresistant temporal lobe epilepsy patients with normal magnetic resonance imaging and normal or non-specific histopathology is not sufficiently presented in the literature. In a retrospective design, we reviewed data of 263 patients who had undergone temporal lobe epilepsy surgery and identified 26 (9.9%) who met the inclusion criteria. Seizure outcomes were determined at 2-year follow-up. Potential predictors of Engel class I (satisfactory outcome) were identified by logistic regression analyses. Engel class I outcome was achieved in 61.5% of patients, 50% being completely seizure free (Engel class IA outcome). The strongest predictors of satisfactory outcome were typical ictal seizure semiology (p = 0.048) and localised ictal discharges on scalp EEG (p = 0.036). Surgery might be an effective treatment choice for the majority of these patients, although outcomes are less favourable than in patients with magnetic resonance imaging-defined lesional temporal lobe epilepsy. Typical ictal seizure semiology and localised ictal discharges on scalp EEG were predictors of Engel class I outcome.
Water quality in turkey farms in Khemisset (Morocco) and potential risk factors.
El Allaoui, A; Rhazi Filali, F; Derouich, A
2016-12-01
The objectives of this study were to assess the microbiological and physical/chemical quality of water in broiler turkey farms in the province of Khemisset (north-western Morocco) and, based on a questionnaire, to ascertain potential risk factors for contamination of drinking water with faecal coliforms. A total of 80 samples were collected and analysed in 20 farms (four from each farm). At the main inlet to the water line at the entrance to each turkey house, 100% of the samples were of unacceptable quality in terms of faecal coliforms, Escherichia coli, faecal streptococci, sulphitereducing anaerobes and enterococci. A significant reduction in microbiological contamination of the water line (p < 0.05) was observed on Day 60. While more than 90% of the samples were of satisfactory quality in terms of pH, nitrites, conductivity, nitrates and iron, only 35% were satisfactory in terms of total hardness and only 20% met quality standards for ammonium content. The factors affecting levels of contamination with faecal coliforms were water chlorination (p = 0.065; odds ratio = 14; 90% confidence interval [CI] = 1.14-71), cleaning and disinfection (p = 0.028; odds ratio = 14; 95% CI = 1.25-156.6) and antibiotic treatment (p = 0.001; odds ratio = 6; 95% CI = 2.1-35.2). To improve water quality in poultry farms, farmers are advised to protect wells from contamination and to install water purification units (pre-oxidation, coagulation, flocculation, disinfection). In addition, turkey houses and rearing equipment should be rigorously cleaned and disinfected between each batch of birds. © OIE (World Organisation for Animal Health), 2016.
Rao, Shalinee; Masilamani, Suresh; Sundaram, Sandhya; Duvuru, Prathiba; Swaminathan, Rajendiran
2016-01-01
Quality monitoring in histopathology unit is categorized into three phases, pre-analytical, analytical and post-analytical, to cover various steps in the entire test cycle. Review of literature on quality evaluation studies pertaining to histopathology revealed that earlier reports were mainly focused on analytical aspects with limited studies on assessment of pre-analytical phase. Pre-analytical phase encompasses several processing steps and handling of specimen/sample by multiple individuals, thus allowing enough scope for errors. Due to its critical nature and limited studies in the past to assess quality in pre-analytical phase, it deserves more attention. This study was undertaken to analyse and assess the quality parameters in pre-analytical phase in a histopathology laboratory. This was a retrospective study done on pre-analytical parameters in histopathology laboratory of a tertiary care centre on 18,626 tissue specimens received in 34 months. Registers and records were checked for efficiency and errors for pre-analytical quality variables: specimen identification, specimen in appropriate fixatives, lost specimens, daily internal quality control performance on staining, performance in inter-laboratory quality assessment program {External quality assurance program (EQAS)} and evaluation of internal non-conformities (NC) for other errors. The study revealed incorrect specimen labelling in 0.04%, 0.01% and 0.01% in 2007, 2008 and 2009 respectively. About 0.04%, 0.07% and 0.18% specimens were not sent in fixatives in 2007, 2008 and 2009 respectively. There was no incidence of specimen lost. A total of 113 non-conformities were identified out of which 92.9% belonged to the pre-analytical phase. The predominant NC (any deviation from normal standard which may generate an error and result in compromising with quality standards) identified was wrong labelling of slides. Performance in EQAS for pre-analytical phase was satisfactory in 6 of 9 cycles. A low incidence of errors in pre-analytical phase implies that a satisfactory level of quality standards was being practiced with still scope for improvement.
Daume, Stefan; Galaz, Victor
2016-01-01
Social media like blogs, micro-blogs or social networks are increasingly being investigated and employed to detect and predict trends for not only social and physical phenomena, but also to capture environmental information. Here we argue that opportunistic biodiversity observations published through Twitter represent one promising and until now unexplored example of such data mining. As we elaborate, it can contribute to real-time information to traditional ecological monitoring programmes including those sourced via citizen science activities. Using Twitter data collected for a generic assessment of social media data in ecological monitoring we investigated a sample of what we denote biodiversity observations with species determination requests (N = 191). These entail images posted as messages on the micro-blog service Twitter. As we show, these frequently trigger conversations leading to taxonomic determinations of those observations. All analysed Tweets were posted with species determination requests, which generated replies for 64% of Tweets, 86% of those contained at least one suggested determination, of which 76% were assessed as correct. All posted observations included or linked to images with the overall image quality categorised as satisfactory or better for 81% of the sample and leading to taxonomic determinations at the species level in 71% of provided determinations. We claim that the original message authors and conversation participants can be viewed as implicit or embryonic citizen science communities which have to offer valuable contributions both as an opportunistic data source in ecological monitoring as well as potential active contributors to citizen science programmes.
Ma, Liyan; Qiu, Bo; Cui, Mingyue; Ding, Jianwei
2017-01-01
Depth image-based rendering (DIBR), which is used to render virtual views with a color image and the corresponding depth map, is one of the key techniques in the 2D to 3D conversion process. Due to the absence of knowledge about the 3D structure of a scene and its corresponding texture, DIBR in the 2D to 3D conversion process, inevitably leads to holes in the resulting 3D image as a result of newly-exposed areas. In this paper, we proposed a structure-aided depth map preprocessing framework in the transformed domain, which is inspired by recently proposed domain transform for its low complexity and high efficiency. Firstly, our framework integrates hybrid constraints including scene structure, edge consistency and visual saliency information in the transformed domain to improve the performance of depth map preprocess in an implicit way. Then, adaptive smooth localization is cooperated and realized in the proposed framework to further reduce over-smoothness and enhance optimization in the non-hole regions. Different from the other similar methods, the proposed method can simultaneously achieve the effects of hole filling, edge correction and local smoothing for typical depth maps in a united framework. Thanks to these advantages, it can yield visually satisfactory results with less computational complexity for high quality 2D to 3D conversion. Numerical experimental results demonstrate the excellent performances of the proposed method. PMID:28407027
Assessing air quality in Aksaray with time series analysis
NASA Astrophysics Data System (ADS)
Kadilar, Gamze Özel; Kadilar, Cem
2017-04-01
Sulphur dioxide (SO2) is a major air pollutant caused by the dominant usage of diesel, petrol and fuels by vehicles and industries. One of the most air-polluted city in Turkey is Aksaray. Hence, in this study, the level of SO2 is analyzed in Aksaray based on the database monitored at air quality monitoring station of Turkey. Seasonal Autoregressive Integrated Moving Average (SARIMA) approach is used to forecast the level of SO2 air quality parameter. The results indicate that the seasonal ARIMA model provides reliable and satisfactory predictions for the air quality parameters and expected to be an alternative tool for practical assessment and justification.
NASA Astrophysics Data System (ADS)
Cao, Zhigang; Duan, Hongtao; Shen, Ming; Ma, Ronghua; Xue, Kun; Liu, Dong; Xiao, Qitao
2018-02-01
Inland lakes are generally an important source of drinking water, and information on their water quality needs to be obtained in real time. To date, Moderate-resolution imaging spectroradiometer (MODIS) data have played a critical, effective and long-term role in fulfilling this function. However, the MODIS instruments on board both the Terra and Aqua satellites have operated beyond their designed five-year mission lifespans (Terra was launched in 1999, whereas Aqua was launched in 2002), and these instruments may stop running at any time in the near future. The Visible Infrared Imager Radiometer Suite (VIIRS) on board the Suomi National Polar-Orbiting Partnership (Suomi NPP, which was launched in Oct 2011) is expected to provide a consistent, long-term data record and continue the series of observations initiated by MODIS. To date, few evaluations of the consistency between VIIRS and MODIS have been conducted for turbid inland waters. In this study, we first used synchronous MODIS/Aqua and VIIRS/NPP data (±1 h) collected during 2012-2015 to evaluate the consistency of Rayleigh-corrected reflectance (Rrc) observations over Lake Hongze (the fourth-largest freshwater lake in China), since accurate remote sensing reflectance (Rrs) values cannot be acquired over turbid inland waters. Second, we used recently developed algorithms based on Rrc in the red band to estimate the concentrations of suspended particulate matter (SPM) from MODIS/Aqua and VIIRS/NPP data. Finally, we assessed the consistency of the SPM products derived from MODIS/Aqua and VIIRS/NPP. The results show the following. (1) The differences in Rrc among the green (VIIRS 551 nm and MODIS 555 nm) and red bands (VIIRS 671 nm and MODIS 645 nm) indicate a satisfactory consistency, and the unbiased percentage difference (UPD) is <12%. Meanwhile, the results for the near infrared (NIR) band (MODIS 859 nm and VIIRS 862 nm) indicate relatively large differences (UPD = 21.84%). (2) The satellite-derived SPM products obtained using MODIS/Aqua and VIIRS/NPP have a satisfactory degree of consistency (0-150 mg/L SPM: R2 = 0.81, UPD < 16% and 0-80 mg/L SPM: R2 = 0.85, UPD < 12%, respectively). These results demonstrate that VIIRS/NPP can continue to record the SPM observations initiated by MODIS/Aqua for turbid inland waters and establish environmental datasets over long time periods to support water quality management endeavors.
O'Keeffe, S T; Lye, M; Donnellan, C; Carmichael, D N
1998-10-01
To examine the reproducibility and responsiveness to change of a six minute walk test and a quality of life measure in elderly patients with heart failure. Longitudinal within patient study. 60 patients with heart failure (mean age 82 years) attending a geriatric outpatient clinic, 45 of whom underwent a repeat assessment three to eight weeks later. Subjects underwent a standardised six minute walk test and completed the chronic heart failure questionnaire (CHQ), a heart failure specific quality of life questionnaire. Intraclass correlation coefficients (ICC) were calculated using a random effects one way analysis of variance as a measure of reproducibility. Guyatt's responsiveness coefficient and effect sizes were calculated as measures of responsiveness to change. 24 patients reported no major change in cardiac status, while seven had deteriorated and 14 had improved between the two clinic visits. Reproducibility was satisfactory (ICC > 0.75) for the six minute walk test, for the total CHQ score, and for the dyspnoea, fatigue, and emotion domains of the CHQ. Effect sizes for all measures were large (> 0.8), and responsiveness coefficients were very satisfactory (> 0.7). Effect sizes for detecting deterioration were greater than those for detecting improvement. Quality of life assessment and a six minute walk test are reproducible and responsive measures of cardiac status in frail, very elderly patients with heart failure.
Jansen, Sylvia J T
2013-01-01
This study focuses on residents' perceptions of residential quality concerning 23 different dwelling aspects. Respondents were asked to indicate their appreciation of these dwelling aspects on a scale ranging from 0 ("extremely unattractive") to 100 ("extremely attractive"). The influence of two potential factors on the appreciation of dwelling aspects is examined: (1) preference and (2) experience. It was hypothesized that residents who live according to their preferences give higher appreciation scores than residents who do not. This should even apply to low-quality housing. Furthermore, it was argued that residents appreciate their current housing situation more than residents who do not live in that particular housing situation. This effect should be independent of preference. The impact of both preference and of experience could be confirmed. The results also showed an interaction effect between preference and experience: the positive effect of experience on appreciation is larger in residents who live in a housing situation that they do not prefer. This result would be expected if the impact of experience works to decrease the 'gap' in residential satisfaction due to the discrepancy between what residents have and what they want. In conclusion, why is housing always satisfactory? In this paper, housing is satisfactory because the 'gap' between what residents want and what they have is small; residents seem to have realistic aspirations. Furthermore, residents appreciate what they already have, even if this is not what they prefer.
Shukla, Surabhi; Einstein, A; Shukla, Abhilasha; Mishra, Deepika
2015-01-01
Background: Liquid-based cytology (LBC), recommended in the mass screening of potentially malignant cervical and oral lesions, suffers from high cost owing to the use of expensive automated devices and materials. Considering the need for cost-effective LBC techniques, we evaluated the efficacy of an inexpensive manual LBC (MLBC) technique against conventional cytological technique in terms of specimen adequacy and smear quality of oral smears. Materials and Methods: Cytological samples were collected from 21 patients using a cytobrush device. After preparation of a conventional smear, the brush containing the remaining sample was immersed in the preservative vial. The preserved material was processed by an MLBC technique and subsequently, direct smears were made from the prepared cell button. Both conventional and MLBC smears were stained by routine Papanicolaou technique and evaluated by an independent observer for the thickness of the smear, cellular distribution, resolution/clarity of cells, cellular staining characteristics and the presence of unsatisfactory background/artifacts. Each parameter was graded as satisfactory; or satisfactory, but limited; or unsatisfactory. Chi-square test was used to compare the values obtained (significance set at P ≤ 0.05). Results: MLBC technique produced a significant number of satisfactory smears with regard to cell distribution, clarity/resolution, staining characteristics and background/artifacts compared to conventional methods. Conclusions: MLBC is a cost-effective cytological technique that may produce oral smears with excellent cytomorphology and longer storage life. PMID:26980958
Little, C L; Barnes, J; Mitchell, R T
2002-12-01
During August 2001 a microbiological study of ready-to-eat cooked rice from take-aways and of chicken sandwiches made on the premises from sandwich bars was undertaken. The intention was to identify risk factors in the production, storage and handling of cooked rice and sandwiches, and to establish their effect on microbiological quality. Examination of cooked rice revealed that the majority of samples (87%; 442 of 508) were of satisfactory/acceptable microbiological quality; 50 (10%) were unsatisfactory, and 16 (3%) were of unacceptable quality due to Bacillus cereus and/or other Bacillus spp in excess of 10(5) cfu/g. The microbiological quality of cooked rice was associated with cuisine type (p < 0.00001), rice type (p < 0.01), cooking (p < 0.01), serving methods (p < 0.00001), and management food hygiene training (p < 0.01). Examination of chicken sandwiches found that most (75%; 335 of 449) were of satisfactory/acceptable microbiological quality and 114 (25%) were unsatisfactory. Acceptable microbiological quality of sandwiches was associated with sandwich bars that had hazard analysis in place (p < 0.05). Smaller businesses, as indicated by Local Authority Inspectors' Consumer at Risk scores, were more likely to have samples classified as unsatisfactory or unacceptable compared to larger businesses (p < 0.001). The majority (90%) of premises had hand-washing facilities accessible and available for use, although only over half (55%) were correctly used as judged by the sampling officer. Where the manager of the premises had received some form of food hygiene training, food safety procedures such as the hazard analysis system were more likely to be in place (p < 0.0001).
[Medical image elastic registration smoothed by unconstrained optimized thin-plate spline].
Zhang, Yu; Li, Shuxiang; Chen, Wufan; Liu, Zhexing
2003-12-01
Elastic registration of medical image is an important subject in medical image processing. Previous work has concentrated on selecting the corresponding landmarks manually and then using thin-plate spline interpolating to gain the elastic transformation. However, the landmarks extraction is always prone to error, which will influence the registration results. Localizing the landmarks manually is also difficult and time-consuming. We the optimization theory to improve the thin-plate spline interpolation, and based on it, used an automatic method to extract the landmarks. Combining these two steps, we have proposed an automatic, exact and robust registration method and have gained satisfactory registration results.
Code of Federal Regulations, 2010 CFR
2010-07-01
... work. (2) To hold and save the United States free from damages in connection with the authorized work... in a manner satisfactory to the Chief of Engineers all installed work during the emergency. (4) To... water quality statements with the request, and the identification of the threat to public health and...
Appreciative Assessment in Academic Advising
ERIC Educational Resources Information Center
He, Ye; Hutson, Bryant
2016-01-01
Academic advising is one of the key functions in higher education. While there has been a development of advising practices in the past decade, the assessment of academic advising practices is far from satisfactory. In this article, we review major academic advising approaches and key characteristics of quality assessment practices. Based on the…
[Virtual bronchoscopy: the correlation between endoscopic simulation and bronchoscopic findings].
Salvolini, L; Gasparini, S; Baldelli, S; Bichi Secchi, E; Amici, F
1997-11-01
We carried out a preliminary clinical validation of 3D spiral CT virtual endoscopic reconstructions of the tracheobronchial tree, by comparing virtual bronchoscopic images with actual endoscopic findings. Twenty-two patients with tracheobronchial disease suspected at preliminary clinical, cytopathological and plain chest film findings were submitted to spiral CT of the chest and bronchoscopy. CT was repeated after endobronchial therapy in 2 cases. Virtual endoscopic shaded-surface-display views of the tracheobronchial tree were reconstructed from reformatted CT data with an Advantage Navigator software. Virtual bronchoscopic images were preliminarily evaluated with a semi-quantitative quality score (excellent/good/fair/poor). The depiction of consecutive airway branches was then considered. Virtual bronchoscopies were finally submitted to double-blind comparison with actual endoscopies. Virtual image quality was considered excellent in 8 cases, good in 14 and fair in 2. Virtual exploration was stopped at the lobar bronchi in one case only; the origin of segmental bronchi was depicted in 23 cases and that of some subsegmental branches in 2 cases. Agreement between actual and virtual bronchoscopic findings was good in all cases but 3 where it was nevertheless considered satisfactory. The yield of clinically useful information differed in 8/24 cases: virtual reconstructions provided more information than bronchoscopy in 5 cases and vice versa in 3. Virtual reconstructions are limited in that the procedure is long and difficult and needing a strictly standardized threshold value not to alter virtual findings. Moreover, the reconstructed surface lacks transparency, there is the partial volume effect and the branches < or = 4 pixels phi and/or meandering ones are difficult to explore. Our preliminary data are encouraging. Segmental bronchi were depicted in nearly all cases, except for the branches involved by disease. Obstructing lesions could be bypassed in some cases, making an indication for endoscopic laser therapy. Future didactic perspectives and applications to minimally invasive or virtual reality-assisted therapy seem promising, even though actual clinical applications require further studies.
Frykman, Philip K; Freedman, Andrew L; Kane, Timothy D; Cheng, Zhi; Petrosyan, Mikael; Catchpole, Kenneth
2017-02-01
We studied operating team acceptability of Video Telescopic Monitor (VITOM ® ) exoscope by exploring the ease of use of the device in two centers. We also assessed factors affecting surgeon musculoskeletal discomfort. We focused on how the operating team interacted with the VITOM system with surrogate measures of usefulness, image quality, ease of use, workload, and setup time. Multivariable linear regression was used to model the relationships between team role, experience, and setup time. Relationships between localized musculoskeletal discomfort and use of VITOM alone, and with loupes, were also analyzed. Four surgeons, 7 surgical techs, 7 circulating nurses, and 13 surgical residents performed 70 pediatric surgical and urological operations. We found that subjective views of each team member were consistently positive with 69%-74% agreed or strongly agreed that VITOM enhanced their ability to perform their job and improved the surgical process. Unexpectedly, the scrub techs and nurses perceived more value and utility of VITOM, presumably because it provides them a view of the operative field that would otherwise be unavailable to them. Team members rated perceptions of image quality highly and workload generally satisfactory. Not surprisingly, setup time decreased with team experience and multivariable modeling showed significant correlations with surgeon and surgical tech experience, but not circulating nurse. An important finding was that surgeon neck discomfort was reduced with use of VITOM alone for magnification, compared with use of loupes and VITOM. The most likely explanation for these findings is improved posture with the neck at a neutral position when viewing the VITOM images, compared with neck flexion with loupes, and thus, a less favorable ergonomic position. This study suggests that there may be small drawbacks associated with VITOM use initially, but these reduce with increased experience and benefit both the surgeon and the rest of the team.
New regularization scheme for blind color image deconvolution
NASA Astrophysics Data System (ADS)
Chen, Li; He, Yu; Yap, Kim-Hui
2011-01-01
This paper proposes a new regularization scheme to address blind color image deconvolution. Color images generally have a significant correlation among the red, green, and blue channels. Conventional blind monochromatic deconvolution algorithms handle each color image channels independently, thereby ignoring the interchannel correlation present in the color images. In view of this, a unified regularization scheme for image is developed to recover edges of color images and reduce color artifacts. In addition, by using the color image properties, a spectral-based regularization operator is adopted to impose constraints on the blurs. Further, this paper proposes a reinforcement regularization framework that integrates a soft parametric learning term in addressing blind color image deconvolution. A blur modeling scheme is developed to evaluate the relevance of manifold parametric blur structures, and the information is integrated into the deconvolution scheme. An optimization procedure called alternating minimization is then employed to iteratively minimize the image- and blur-domain cost functions. Experimental results show that the method is able to achieve satisfactory restored color images under different blurring conditions.
Strategic issues in preventing cataract blindness in developing countries.
Ellwein, L. B.; Kupfer, C.
1995-01-01
Cataract blindness is a public health problem of major proportions in developing countries. Intracapsular cataract extraction with aphakic spectacles has been the standard surgical technique for restoring sight. Because of image magnification in the operated eye, however, the result in unilaterally blind patients is less than satisfactory. Fortunately, with the availability of low-cost intraocular lenses (IOL) and ophthalmologists trained in extracapsular surgery, it is now practical to intervene successfully in the unilateral case. The need for increased attention on the quality of the visual high prevalence of cataract blindness in developing countries and an increasing cataract incidence due to an aging population require substantial increases in surgical volume. The third issue relates to cost. If significant increases in surgical volume and quality of outcomes are to be realized without an increased need for external funding, service delivery must be made more efficient. The expansion of IOL surgery for unilateral blindness is a favourable trend in ensuring financial sustainability of delivery systems; patients can be operated on while still economically productive and able to pay rather than waiting for bilateral blindness and a less favourable economic and social impact. If the quality, volume, and cost issues are to be successfully addressed, operational and structural changes to eye care delivery systems are necessary. These changes can be effected through training, technology introduction, management of facilities, social marketing, organizational partnerships, and evaluation. With improved understanding of the critical factors in successful models their widespread replication will be facilitated. PMID:8846495
Liu, Dan; Liu, Xuejun; Wu, Yiguang
2018-04-24
This paper presents an effective approach for depth reconstruction from a single image through the incorporation of semantic information and local details from the image. A unified framework for depth acquisition is constructed by joining a deep Convolutional Neural Network (CNN) and a continuous pairwise Conditional Random Field (CRF) model. Semantic information and relative depth trends of local regions inside the image are integrated into the framework. A deep CNN network is firstly used to automatically learn a hierarchical feature representation of the image. To get more local details in the image, the relative depth trends of local regions are incorporated into the network. Combined with semantic information of the image, a continuous pairwise CRF is then established and is used as the loss function of the unified model. Experiments on real scenes demonstrate that the proposed approach is effective and that the approach obtains satisfactory results.
Teman, Carolin J.; Wilson, Andrew R.; Perkins, Sherrie L.; Hickman, Kimberly; Prchal, Josef T.; Salama, Mohamed E.
2010-01-01
Evaluation of bone marrow fibrosis and osteosclerosis in myeloproliferative neoplasms (MPN) is subject to interobserver inconsistency. Performance data for currently utilized fibrosis grading systems are lacking, and classification scales for osteosclerosis do not exist. Digital imaging can serve as a quantification method for fibrosis and osteosclerosis. We used digital imaging techniques for trabecular area assessment and reticulin-fiber quantification. Patients with all Philadelphia negative MPN subtypes had higher trabecular volume than controls (p ≤0.0015). Results suggest that the degree of osteosclerosis helps differentiate primary myelofibrosis from other MPN. Numerical quantification of fibrosis highly correlated with subjective scores, and interobserver correlation was satisfactory. Digital imaging provides accurate quantification for osteosclerosis and fibrosis. PMID:20122729
Large leiomyoma of the bladder masquerading as an enlarged prostate gland.
Itam, Sarah; Elhage, Oussama; Khan, Muhammad Shamim
2016-02-23
A 56-year-old man was admitted to hospital with shortness of breath and subsequently sustained a cardiac arrest. In the recovery period, he developed acute urinary retention and haematuria. Imaging suggested an enlarged prostate and he was started on clean intermittent catheterisation. Following further imaging and a transurethral biopsy, he was found to have a bladder leiomyoma. This was treated with laparotomy, cystotomy and enucleation of the tumour. At his 6-week follow-up appointment, he had a satisfactory cystogram and a successful void without catheter. 2016 BMJ Publishing Group Ltd.
Large leiomyoma of the bladder masquerading as an enlarged prostate gland
Itam, Sarah; Elhage, Oussama; Khan, Muhammad Shamim
2016-01-01
A 56-year-old man was admitted to hospital with shortness of breath and subsequently sustained a cardiac arrest. In the recovery period, he developed acute urinary retention and haematuria. Imaging suggested an enlarged prostate and he was started on clean intermittent catheterisation. Following further imaging and a transurethral biopsy, he was found to have a bladder leiomyoma. This was treated with laparotomy, cystotomy and enucleation of the tumour. At his 6-week follow-up appointment, he had a satisfactory cystogram and a successful void without catheter. PMID:26907817
2017-12-01
satisfactory performance. We do not use statistical models, and we do not create patterns that require supervised learning. Our methodology is intended...statistical models, and we do not create patterns that require supervised learning. Our methodology is intended for use in personal digital image...THESIS MOTIVATION .........................................................................19 III. METHODOLOGY
Historical overview of V/STOL aircraft technology
NASA Technical Reports Server (NTRS)
Anderson, S. B.
1981-01-01
The requirements for satisfactory characteristics in several key technology areas are discussed and a review is made of various V/STOL aircraft for the purpose of assessing the success or failure of each design in meeting design requirements. Special operating techniques were developed to help circumvent deficiencies. For the most part performance and handling qualities limitations restricted operational evaluations. Flight operations emphasized the need for good STOL performance, good handling qualities, and stability and control augmentation. The majority of aircraft suffered adverse ground effects.
Further exploration of MRI techniques for liver T1rho quantification.
Zhao, Feng; Yuan, Jing; Deng, Min; Lu, Pu-Xuan; Ahuja, Anil T; Wang, Yi-Xiang J
2013-12-01
With biliary duct ligation and CCl4 induced rat liver fibrosis models, recent studies showed that MR T1rho imaging is able to detect liver fibrosis, and the degree of fibrosis is correlated with the degree of elevation of the T1rho measurements, suggesting liver T1rho quantification may play an important role for liver fibrosis early detection and grading. It has also been reported it is feasible to obtain consistent liver T1rho measurement for human subjects at 3 Tesla (3 T), and preliminary clinical data suggest liver T1rho is increased in patients with cirrhosis. In these previous studies, T1rho imaging was used with the rotary-echo spin-lock pulse for T1rho preparation, and number of signal averaging (NSA) was 2. Due to the presence of inhomogeneous B0 field, artifacts may occur in the acquired T1rho-weighted images. The method described by Dixon et al. (Magn Reson Med 1996;36:90-4), which is a hard RF pulse with 135° flip angle and same RF phase as the spin-locking RF pulse is inserted right before and after the spin-locking RF pulse, has been proposed to reduce sensitivity to B0 field inhomogeneity in T1rho imaging. In this study, we compared the images scanned by rotary-echo spin-lock pulse method (sequence 1) and the pulse modified according to Dixon method (sequence 2). When the artifacts occurred in T1rho images, we repeated the same scan until satisfactory. We accepted images if artifact in liver was less than 10% of liver area by visual estimation. When NSA =2, the breath-holding duration for data acquisition of one slice scanning was 8 sec due to a delay time of 6,000 ms for magnetization restoration. If NSA =1, the duration was shortened to be 2 sec. In previous studies, manual region of interest (ROI) analysis of T1rho map was used. In this current study, histogram analysis was also applied to evaluate liver T1rho value on T1rho maps. MRI data acquisition was performed on a 3 T clinical scanner. There were 29 subjects with 61 examinations obtained. Liver T1rho values obtained by sequence 1 (NSA =2) and sequence 2 (NSA =2) showed similar values, i.e., 43.1±2.1 ms (range: 38.6-48.0 ms, n=40 scans) vs. 43.5±2.5 ms (range: 39.0-47.7 ms, n=12 scans, P=0.74) respectively. For the six volunteers scanned with both sequences in one session, the intraclass correlation coefficient (ICC) was 0.939. Overall, the success rate of obtaining satisfactory images per acquisition was slightly over 50% for both sequence 1 and sequence 2. Satisfactory images can usually be obtained by asking the volunteer subjects to better hold their breath. However, sequence 2 did not increase the scan success rate. For the nine subjects scanned by sequence 2 with both NSA =2 and NSA =1 during one session, the ICC was 0.274, demonstrated poor agreement. T1rho measurement by ROI method and histogram had an ICC of 0.901 (P>0.05), demonstrated very good agreement. We conclude that by including 135° flip angle before and after the spin-locking RF pulse, the rate of artifacts occurring did not decrease. On the other hand, sequence 1 and sequence 2 measured similar T1rho value in healthy liver. While reducing the breath-holding duration significantly, NSA =1 did not offer satisfactory signal-to-noise ratio. Histogram measurement can be adopted for future studies.
A translational velocity command system for VTOL low speed flight
NASA Technical Reports Server (NTRS)
Merrick, V. K.
1982-01-01
A translational velocity flight controller, suitable for very low speed maneuvering, is described and its application to a large class of VTOL aircraft from jet lift to propeller driven types is analyzed. Estimates for the more critical lateral axis lead to the conclusion that the controller would provide a jet lift (high disk loading) VTOL aircraft with satisfactory "hands off" station keeping in operational conditions more stringent than any specified in current or projected requirements. It also seems likely that ducted fan or propeller driven (low disk loading) VTOL aircraft would have acceptable hovering handling qualities even in high turbulence, although in these conditions pilot intervention to maintain satisfactory station keeping would probably be required for landing in restricted areas.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stützer, Kristin; Haase, Robert; Exner, Florian
2016-09-15
Purpose: Rating both a lung segmentation algorithm and a deformable image registration (DIR) algorithm for subsequent lung computed tomography (CT) images by different evaluation techniques. Furthermore, investigating the relative performance and the correlation of the different evaluation techniques to address their potential value in a clinical setting. Methods: Two to seven subsequent CT images (69 in total) of 15 lung cancer patients were acquired prior, during, and after radiochemotherapy. Automated lung segmentations were compared to manually adapted contours. DIR between the first and all following CT images was performed with a fast algorithm specialized for lung tissue registration, requiring themore » lung segmentation as input. DIR results were evaluated based on landmark distances, lung contour metrics, and vector field inconsistencies in different subvolumes defined by eroding the lung contour. Correlations between the results from the three methods were evaluated. Results: Automated lung contour segmentation was satisfactory in 18 cases (26%), failed in 6 cases (9%), and required manual correction in 45 cases (66%). Initial and corrected contours had large overlap but showed strong local deviations. Landmark-based DIR evaluation revealed high accuracy compared to CT resolution with an average error of 2.9 mm. Contour metrics of deformed contours were largely satisfactory. The median vector length of inconsistency vector fields was 0.9 mm in the lung volume and slightly smaller for the eroded volumes. There was no clear correlation between the three evaluation approaches. Conclusions: Automatic lung segmentation remains challenging but can assist the manual delineation process. Proven by three techniques, the inspected DIR algorithm delivers reliable results for the lung CT data sets acquired at different time points. Clinical application of DIR demands a fast DIR evaluation to identify unacceptable results, for instance, by combining different automated DIR evaluation methods.« less
Theory of the amplitude-phase retrieval in any linear-transform system and its applications
NASA Astrophysics Data System (ADS)
Yang, Guozhen; Gu, Ben-Yuan; Dong, Bi-Zhen
1992-12-01
This paper is a summary of the theory of the amplitude-phase retrieval problem in any linear transform system and its applications based on our previous works in the past decade. We describe the general statement on the amplitude-phase retrieval problem in an imaging system and derive a set of equations governing the amplitude-phase distribution in terms of the rigorous mathematical derivation. We then show that, by using these equations and an iterative algorithm, a variety of amplitude-phase problems can be successfully handled. We carry out the systematic investigations and comprehensive numerical calculations to demonstrate the utilization of this new algorithm in various transform systems. For instance, we have achieved the phase retrieval from two intensity measurements in an imaging system with diffraction loss (non-unitary transform), both theoretically and experimentally, and the recovery of model real image from its Hartley-transform modulus only in one and two dimensional cases. We discuss the achievement of the phase retrieval problem from a single intensity only based on the sampling theorem and our algorithm. We also apply this algorithm to provide an optimal design of the phase-adjusted plate for a phase-adjustment focusing laser accelerator and a design approach of single phase-only element for implementing optical interconnect. In order to closely simulate the really measured data, we examine the reconstruction of image from its spectral modulus corrupted by a random noise in detail. The results show that the convergent solution can always be obtained and the quality of the recovered image is satisfactory. We also indicated the relationship and distinction between our algorithm and the original Gerchberg- Saxton algorithm. From these studies, we conclude that our algorithm shows great capability to deal with the comprehensive phase-retrieval problems in the imaging system and the inverse problem in solid state physics. It may open a new way to solve important inverse source problems extensively appearing in physics.
SparseBeads data: benchmarking sparsity-regularized computed tomography
NASA Astrophysics Data System (ADS)
Jørgensen, Jakob S.; Coban, Sophia B.; Lionheart, William R. B.; McDonald, Samuel A.; Withers, Philip J.
2017-12-01
Sparsity regularization (SR) such as total variation (TV) minimization allows accurate image reconstruction in x-ray computed tomography (CT) from fewer projections than analytical methods. Exactly how few projections suffice and how this number may depend on the image remain poorly understood. Compressive sensing connects the critical number of projections to the image sparsity, but does not cover CT, however empirical results suggest a similar connection. The present work establishes for real CT data a connection between gradient sparsity and the sufficient number of projections for accurate TV-regularized reconstruction. A collection of 48 x-ray CT datasets called SparseBeads was designed for benchmarking SR reconstruction algorithms. Beadpacks comprising glass beads of five different sizes as well as mixtures were scanned in a micro-CT scanner to provide structured datasets with variable image sparsity levels, number of projections and noise levels to allow the systematic assessment of parameters affecting performance of SR reconstruction algorithms6. Using the SparseBeads data, TV-regularized reconstruction quality was assessed as a function of numbers of projections and gradient sparsity. The critical number of projections for satisfactory TV-regularized reconstruction increased almost linearly with the gradient sparsity. This establishes a quantitative guideline from which one may predict how few projections to acquire based on expected sample sparsity level as an aid in planning of dose- or time-critical experiments. The results are expected to hold for samples of similar characteristics, i.e. consisting of few, distinct phases with relatively simple structure. Such cases are plentiful in porous media, composite materials, foams, as well as non-destructive testing and metrology. For samples of other characteristics the proposed methodology may be used to investigate similar relations.
Jia, Xun; Lou, Yifei; Li, Ruijiang; Song, William Y; Jiang, Steve B
2010-04-01
Cone-beam CT (CBCT) plays an important role in image guided radiation therapy (IGRT). However, the large radiation dose from serial CBCT scans in most IGRT procedures raises a clinical concern, especially for pediatric patients who are essentially excluded from receiving IGRT for this reason. The goal of this work is to develop a fast GPU-based algorithm to reconstruct CBCT from undersampled and noisy projection data so as to lower the imaging dose. The CBCT is reconstructed by minimizing an energy functional consisting of a data fidelity term and a total variation regularization term. The authors developed a GPU-friendly version of the forward-backward splitting algorithm to solve this model. A multigrid technique is also employed. It is found that 20-40 x-ray projections are sufficient to reconstruct images with satisfactory quality for IGRT. The reconstruction time ranges from 77 to 130 s on an NVIDIA Tesla C1060 (NVIDIA, Santa Clara, CA) GPU card, depending on the number of projections used, which is estimated about 100 times faster than similar iterative reconstruction approaches. Moreover, phantom studies indicate that the algorithm enables the CBCT to be reconstructed under a scanning protocol with as low as 0.1 mA s/projection. Comparing with currently widely used full-fan head and neck scanning protocol of approximately 360 projections with 0.4 mA s/projection, it is estimated that an overall 36-72 times dose reduction has been achieved in our fast CBCT reconstruction algorithm. This work indicates that the developed GPU-based CBCT reconstruction algorithm is capable of lowering imaging dose considerably. The high computation efficiency in this algorithm makes the iterative CBCT reconstruction approach applicable in real clinical environments.
Soil Management for Hardwood Production
W. M. Broadfoot; B. G. Blackmon; J. B. Baker
1971-01-01
Soil management is the key to successful hardwood management because soil properties are probably the most important determinants of forest productivity. Because of the lack of soil uniformity, however, many foresters have become frustrated with attempts to relate soil to satisfactory growth. Since soil scientists have been unable to predict site quality for trees in...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-09
... single meter reading platform and in-home monitoring devices. Residential water meters have been supplied... Central Iowa Water Association AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA... reasonably available quantities and of a satisfactory quality] to the Central Iowa Water Association (CIWA...
ERIC Educational Resources Information Center
Wilson, Jennifer
2016-01-01
Despite its imperfections, academic peer review has been accepted as a satisfactory process by which assessment panels comprised of different disciplinary representatives arrive at agreement through a system of shared rules and language that respects disciplinary plurality. Artistic researchers, whose output is required to meet both scholarly…
NASA Astrophysics Data System (ADS)
Czan, Andrej; Babík, Ondrej; Miklos, Matej; Záušková, Lucia; Mezencevová, Viktória
2017-10-01
Since most of the implant surface is in direct contact with bone tissue, shape and integrity of said surface has great influence on successful osseointegration. Among other characteristics that predetermine titanium of different grades of pureness as ideal biomaterial, titanium shows high mechanical strength making precise miniature machining increasingly difficult. Current titanium-based implants are often anodized due to colour coding. This anodized layer has important functional properties for right usage and also bio-compatibility of dental implants. Physical method of anodizing and usage of anodizing mediums has a significant influence on the surface quality and itself functionality. However, basic requirement of the dental implant with satisfactory properties is quality of machined surface before anodizing. Roughness, for example, is factor affecting of time length of anodizing operation and so whole productivity. The paper is focused on monitoring of surface and area characteristics, such as roughness or surface integrity after different cutting conditions of miniature machining of dental implants and their impact on suitability for creation of satisfactory anodized layer with the correct biocompatible functional properties.
NASA Technical Reports Server (NTRS)
Grantham, W. D.; Deal, P. L.; Keyser, G. L., Jr.; Smith, P. M.
1983-01-01
A six degree-of-freedom, ground-based simulator study was conducted to evaluate the low speed flight characteristics of a twin fuselage cargo transport airplane and to compare these characteristics with those of a large, single fuselage (reference) transport configuration which was similar to the Lockheed C-5C airplane. The primary piloting task was the approach and landing. The results indicated that in order to achieve "acceptable' low speed handling qualities on the twin fuselage concept, considerable stability and control augmentation was required, and although the augmented airplane could be landed safely under adverse conditions, the roll performance of the aircraft had to be improved appreciably before the handling qualities were rated as being "satisfactory.' These ground-based simulation results indicated that a value of t sub phi = 30 (time required to bank 30 deg) less than 6 sec should result in "acceptable' roll response characteristics, and when t sub phi = 30 is less than 3.8 sec, "satisfactory' roll response should be attainable on such large and unusually configured aircraft as the subject twin fuselage cargo transport concept.
Photoacoustic-Based Multimodal Nanoprobes: from Constructing to Biological Applications.
Gao, Duyang; Yuan, Zhen
2017-01-01
Multimodal nanoprobes have attracted intensive attentions since they can integrate various imaging modalities to obtain complementary merits of single modality. Meanwhile, recent interest in laser-induced photoacoustic imaging is rapidly growing due to its unique advantages in visualizing tissue structure and function with high spatial resolution and satisfactory imaging depth. In this review, we summarize multimodal nanoprobes involving photoacoustic imaging. In particular, we focus on the method to construct multimodal nanoprobes. We have divided the synthetic methods into two types. First, we call it "one for all" concept, which involves intrinsic properties of the element in a single particle. Second, "all in one" concept, which means integrating different functional blocks in one particle. Then, we simply introduce the applications of the multifunctional nanoprobes for in vivo imaging and imaging-guided tumor therapy. At last, we discuss the advantages and disadvantages of the present methods to construct the multimodal nanoprobes and share our viewpoints in this area.
Biomedical photoacoustics: fundamentals, instrumentation and perspectives on nanomedicine
Zou, Chunpeng; Wu, Beibei; Dong, Yanyan; Song, Zhangwei; Zhao, Yaping; Ni, Xianwei; Yang, Yan; Liu, Zhe
2017-01-01
Photoacoustic imaging (PAI) is an integrated biomedical imaging modality which combines the advantages of acoustic deep penetration and optical high sensitivity. It can provide functional and structural images with satisfactory resolution and contrast which could provide abundant pathological information for disease-oriented diagnosis. Therefore, it has found vast applications so far and become a powerful tool of precision nanomedicine. However, the investigation of PAI-based imaging nanomaterials is still in its infancy. This perspective article aims to summarize the developments in photoacoustic technologies and instrumentations in the past years, and more importantly, present a bright outlook for advanced PAI-based imaging nanomaterials as well as their emerging biomedical applications in nanomedicine. Current challenges and bottleneck issues have also been discussed and elucidated in this article to bring them to the attention of the readership. PMID:28053532
MToS: A Tree of Shapes for Multivariate Images.
Carlinet, Edwin; Géraud, Thierry
2015-12-01
The topographic map of a gray-level image, also called tree of shapes, provides a high-level hierarchical representation of the image contents. This representation, invariant to contrast changes and to contrast inversion, has been proved very useful to achieve many image processing and pattern recognition tasks. Its definition relies on the total ordering of pixel values, so this representation does not exist for color images, or more generally, multivariate images. Common workarounds, such as marginal processing, or imposing a total order on data, are not satisfactory and yield many problems. This paper presents a method to build a tree-based representation of multivariate images, which features marginally the same properties of the gray-level tree of shapes. Briefly put, we do not impose an arbitrary ordering on values, but we only rely on the inclusion relationship between shapes in the image definition domain. The interest of having a contrast invariant and self-dual representation of multivariate image is illustrated through several applications (filtering, segmentation, and object recognition) on different types of data: color natural images, document images, satellite hyperspectral imaging, multimodal medical imaging, and videos.
An approach for traffic prohibition sign detection
NASA Astrophysics Data System (ADS)
Li, Qingquan; Xu, Dihong; Li, Bijun; Zeng, Zhe
2006-10-01
This paper presents an off-line traffic prohibition sign detection approach, whose core is based on combination with the color feature of traffic prohibition signs, shape feature and degree of circularity. Matlab-Image-processing toolbox is used for this purpose. In order to reduce the computational cost, a pre-processing of the image is applied before the core. Then, we employ the obvious redness attribute of prohibition signs to coarsely eliminate the non-redness image in the input data. Again, a edge-detection operator, Canny edge detector, is applied to extract the potential edge. Finally, Degree of circularity is used to verdict the traffic prohibition sign. Experimental results show that our systems offer satisfactory performance.
Deep convolutional neural network for prostate MR segmentation
NASA Astrophysics Data System (ADS)
Tian, Zhiqiang; Liu, Lizhi; Fei, Baowei
2017-03-01
Automatic segmentation of the prostate in magnetic resonance imaging (MRI) has many applications in prostate cancer diagnosis and therapy. We propose a deep fully convolutional neural network (CNN) to segment the prostate automatically. Our deep CNN model is trained end-to-end in a single learning stage based on prostate MR images and the corresponding ground truths, and learns to make inference for pixel-wise segmentation. Experiments were performed on our in-house data set, which contains prostate MR images of 20 patients. The proposed CNN model obtained a mean Dice similarity coefficient of 85.3%+/-3.2% as compared to the manual segmentation. Experimental results show that our deep CNN model could yield satisfactory segmentation of the prostate.
Madan, S S; Boeree, N R
2003-12-01
Posterior lumbar interbody fusion (PLIF) restores disc height, the load bearing ability of anterior ligaments and muscles, root canal dimensions, and spinal balance. It immobilizes the painful degenerate spinal segment and decompresses the nerve roots. Anterior lumbar interbody fusion (ALIF) does the same, but could have complications of graft extrusion, compression and instability contributing to pseudarthrosis in the absence of instrumentation. The purpose of this study was to assess and compare the outcome of instrumented circumferential fusion through a posterior approach [PLIF and posterolateral fusion (PLF)] with instrumented ALIF using the Hartshill horseshoe cage, for comparable degrees of internal disc disruption and clinical disability. It was designed as a prospective study, comparing the outcome of two methods of instrumented interbody fusion for internal disc disruption. Between April 1994 and June 1998, the senior author (N.R.B.) performed 39 instrumented ALIF procedures and 35 instrumented circumferential fusion with PLIF procedures. The second author, an independent assessor (S.M.), performed the entire review. Preoperative radiographic assessment included plain radiographs, magnetic resonance imaging (MRI) and provocative discography in all the patients. The outcome in the two groups was compared in terms of radiological improvement and clinical improvement, measured on the basis of improvement of back pain and work capacity. Preoperatively, patients were asked to fill out a questionnaire giving their demographic details, maximum walking distance and current employment status in order to establish the comparability of the two groups. Patient assessment was with the Oswestry Disability Index, quality of life questionnaire (subjective), pain drawing, visual analogue scale, disability benefit, compensation status, and psychological profile. The results of the study showed a satisfactory outcome (score< or =30) on the subjective (quality of life questionnaire) score of 71.8% (28 patients) in the ALIF group and 74.3% (26 patients) in the PLIF group (P>0.05). On categorising Oswestry Index scores into "excellent", "better", "same", and "worse", we found no difference in outcome between the two groups: 79.5% (n=31) had satisfactory outcome with ALIF and 80% (n=28) had satisfactory outcome with PLIF. The rate of return to work was no different in the two groups. On radiological assessment, we found two nonunions in the circumferential fusion (PLIF) group (94.3% fusion rate) and indirect evidence of no nonunions in the ALIF group. There was no significant difference between the compensation rate and disability benefit rate between the two groups. There were three complications in ALIF group and four in the PLIF (circumferential) group. On the basis of these results, we conclude that it is possible to treat discogenic back pain by anterior interbody fusion with Hartshill horseshoe cage or with circumferential fusion using instrumented PLIF.
Cappello, Carmelina; Tremolaterra, Fabrizio; Pascariello, Annalisa; Ciacci, Carolina; Iovino, Paola
2013-03-01
The aim of this study is to test in a double-blinded, randomised placebo-controlled study the effects of a commercially available multi-strain symbiotic mixture on symptoms, colonic transit and quality of life in irritable bowel syndrome (IBS) patients who meet Rome III criteria. There is only one other double-blinded RCT on a single-strain symbiotic mixture in IBS. This is a double-blinded, randomised placebo-controlled study of a symbiotic mixture (Probinul, 5 g bid) over 4 weeks after 2 weeks of run-in. The primary endpoints were global satisfactory relief of abdominal flatulence and bloating. Responders were patients who reported at least 50 % of the weeks of treatment with global satisfactory relief. The secondary endpoints were change in abdominal bloating, flatulence, pain and urgency by a 100-mm visual analog scale, stool frequency and bowel functions on validated adjectival scales (Bristol Scale and sense of incomplete evacuation). Pre- and post-treatment colonic transit time (Metcalf) and quality of life (SF-36) were assessed. Sixty-four IBS patients (symbiotic n = 32, 64 % females, mean age 38.7 ± 12.6 years) were studied. This symbiotic mixture reduced flatulence over a 4-week period of treatment (repeated-measures analysis of covariance, p < 0.05). Proportions of responders were not significantly different between groups. At the end of the treatment, a longer rectosigmoid transit time and a significant improvement in most SF-36 scores were observed in the symbiotic group. This symbiotic mixture has shown a beneficial effect in decreasing the severity of flatulence in IBS patients, a lack of adverse events and a good side-effect profile; however, it failed to achieve an improvement in global satisfactory relief of abdominal flatulence and bloating. Further studies are warranted.
Validation of the QUEST for German-speaking countries.
Hopfner, Franziska; Nebel, Adelheid; Lyons, Kelly E; Tröster, Alexander I; Kuhlenbäumer, Gregor; Deuschl, Günther; Martinez-Martin, Pablo
2016-01-01
To explore the clinimetric attributes of the German version of the quality of life in essential tremor (ET) questionnaire (QUEST) as a tremor-specific measure of quality of life. This was an observational, cross-sectional study. The QUEST German version was obtained by translation-back translation procedure. ET cases were diagnosed according to the tremor investigation group criteria. Assessments included Archimedes spirals rating, EQ-5D, Beck Depression Inventory (BDI-II) and QUEST German version. Missing data were imputed for those cases in which the loss of data for one domain of the QUEST was <30%. Ninety three patients out of 138 (67.4%) with definite or probable ET had complete QUEST data after 43 item imputations and they constituted the sample for this study. The QUEST summary index (QSI) displayed no floor or ceiling effects. QUEST internal consistency (Cronbach's alpha) ranged between 0.50 and 0.89. Item-total domain correlations ranged from 0.26 to 0.82 and the item homogeneity indexes were satisfactory (range: 0.28-0.60). The QSI correlated weakly with the EQ-5D (rS=0.20) and moderately with the BDI-II (rS = 0.31) and the QUEST self-evaluation of tremor severity (rS = 0.44). The QUEST German version has, despite recognized data quality problems, satisfactory acceptability and internal consistency as a whole. The correlation analysis showed that tremor in the head, voice and right hand was moderately associated with quality of life.
Sensakovic, William F; O'Dell, M Cody; Letter, Haley; Kohler, Nathan; Rop, Baiywo; Cook, Jane; Logsdon, Gregory; Varich, Laura
2016-10-01
Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA(2) by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P < 0.0001). Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing can significantly impact image quality when settings are left near default values.
Scan angle calculation and image compositing for the Mexico forest mapping project
Zhiliang Zhu
1994-01-01
Data from the Advanced Very High Resolution Radiometer (AVHRR) were used in a cooperative project, sponsored by the U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station, and the United Nations, Food and Agriculture Organization (FAO), to map Mexicos forest cover types.To provide satisfactory AVHRR data sets for the project, the sensor scan...
Mapping Surface Soil Organic Carbon for Crop Fields with Remote Sensing
NASA Technical Reports Server (NTRS)
Chen, Feng; Kissel, David E.; West, Larry T.; Rickman, Doug; Luvall, J. C.; Adkins, Wayne
2004-01-01
The organic C concentration of surface soil can be used in agricultural fields to vary crop production inputs. Organic C is often highly spatially variable, so that maps of soil organic C can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic C on three fields, using remotely sensed images of the fields with a bare surface. Enough soil samples covering the range in soil organic C must be taken from each field to develop a satisfactory relationship between soil organic C content and image reflectance values. The number of soil samples analyzed in the three fields varied from 22 to 26. The regression equations differed between fields, but gave highly significant relationships with R2 values of 0.93, 0.95, and 0.89 for the three fields. A comparison of predicted and measured values of soil organic C for an independent set of 2 soil samples taken on one of the fields gave highly satisfactory results, with a comparison equation of % organic C measured + 1.02% organic C predicted, with r2 = 0.87.
NASA Astrophysics Data System (ADS)
Polito, C.; Pani, R.; Trigila, C.; Cinti, M. N.; Fabbri, A.; Frantellizzi, V.; De Vincentis, G.; Pellegrini, R.; Pani, R.
2017-01-01
The growing interest for new scintillation crystals with outstanding imaging performances (i.e. resolution and efficiency) has suggested the study of recently discovered scintillators named CRY018 and CRY019. The crystals under investigation are monolithic and have shown enhanced characteristics both for gamma ray spectrometry and for Nuclear Medicine imaging applications such as the dual isotope imaging. Moreover, the non-hygroscopic nature and the absence of afterglow make these scintillators even more attractive for the potential improvement in a wide range of applications. These scintillation crystals show a high energy resolution in the energy range involved in Nuclear Medicine, allowing the discrimination between very close energy values. Moreover, in order to prove their suitability of being powerful imaging systems, the imaging performances like the position linearity and the intrinsic spatial resolution have been evaluated obtaining satisfactory results thanks to the implementation of an optimized algorithm for the images reconstruction.
Measuring and Improving the Quality of Preprocedural Assessments.
Manji, Farah; McCarty, Kelsey; Kurzweil, Vanessa; Mark, Eden; Rathmell, James P; Agarwala, Aalok V
2017-06-01
Preprocedural assessments are used by anesthesia providers to optimize perioperative care for patients undergoing invasive procedures. When these assessments are performed in advance by providers who are not caring for the patient during the procedure, there is an additional layer of complexity in ensuring that the workup meets the needs of the primary anesthesia care team. In this study, anesthesia providers were asked to rate the quality of preprocedural assessments prepared by other providers to evaluate anesthesia care team satisfaction. Quality ratings for preprocedural assessments were collected from anesthesia providers on the day of surgery using an electronic quality assurance tool from January 9, 2014 to October 21, 2014. Users could rate assessments as "exemplary," "satisfactory," or "unsatisfactory." Free text comments could be entered for any of the quality ratings chosen. A reviewer trained in clinical anesthesia categorized all comments as "positive," "constructive," or "neutral" and conducted in-depth chart reviews triggered by 67 "constructive" comments submitted during the first 3 months of data collection to further subcategorize perceived deficiencies in the preprocedural assessments. In May 2014, providers were asked to participate in a midpoint survey and provide general feedback about the preprocedural process and evaluations. 37,611 procedures requiring anesthesia were analyzed. Of the 17,522 (46.6%) cases with a rated preprocedural assessment, anesthesia providers rated 3828 (21.8%) as "exemplary," 13,454 (76.8%) as "satisfactory," and 240 (1.4%) as "unsatisfactory." The monthly proportion of "unsatisfactory" ratings ranged from 3.1% to 0% over the study period, whereas the midpoint survey showed that anesthesia providers estimated that the number of unsatisfactory evaluations was 11.5%. Preprocedural evaluations performed on inpatients received significantly better ratings than evaluations performed on outpatients by the preadmission testing clinic or phone program (P < .0001). The most common reason given for "unsatisfactory" ratings was a perception of "missing information" (49.2%). Chart reviews revealed that inadequate documentation was in reality the most common deficiency in preprocedural evaluations (35 of 67 reviews, 52.2%). The overwhelming majority of preprocedural assessments performed at our institution were considered satisfactory or exemplary by day-of-surgery anesthesia providers. This was demonstrated by both the case-by-case ratings and midpoint survey. However, the perceived frequency of "unsatisfactory" evaluations was worse when providers were asked to reflect on the quality of preprocedural evaluations generally versus rate them individually. Analysis of comments left by providers allowed us to identify specific and actionable areas for improvement. This method can be used by other institutions to identify systemic deficiencies in the preprocedural evaluation process.
Influence of leadership on quality nursing care.
Mendes, Luis; Fradique, Maria de Jesus José Gil
2014-01-01
The purpose of this paper is to investigate the extent to which nursing leadership, perceived by nursing staff, influences nursing quality. Data were collected between August and October 2011 in a Portuguese health center via a questionnaire completed by nurses. Our original sample included 283 employees; 184 questionnaires were received (65% response). The theoretical model presents reasonably satisfactory fit indices (values above literature reference). Path analysis between latent constructs clearly suggests that nursing leadership has a direct (beta = 0.724) and statistically significant (p = 0.007) effect on nursing quality. Results reinforce several ideas propagated throughout the literature, which suggests the relationship's relevance, but lacks empirical support, which this study corrects.
Chuang, Tzu-Chao; Huang, Hsuan-Hung; Chang, Hing-Chiu; Wu, Ming-Ting
2014-06-01
To achieve better spatial and temporal resolution of dynamic contrast-enhanced MR imaging, the concept of k-space data sharing, or view sharing, can be implemented for PROPELLER acquisition. As found in other view-sharing methods, the loss of high-resolution dynamics is possible for view-sharing PROPELLER (VS-Prop) due to the temporal smoothing effect. The degradation can be more severe when a narrow blade with less phase encoding steps is chosen in the acquisition for higher frame rate. In this study, an iterative algorithm termed pixel-based optimal blade selection (POBS) is proposed to allow spatially dependent selection of the rotating blades, to generate high-resolution dynamic images with minimal reconstruction artifacts. In the reconstruction of VS-Prop, the central k-space which dominates the image contrast is only provided by the target blade with the peripheral k-space contributed by a minimal number of consecutive rotating blades. To reduce the reconstruction artifacts, the set of neighboring blades exhibiting the closest image contrast with the target blade is picked by POBS algorithm. Numerical simulations and phantom experiments were conducted in this study to investigate the dynamic response and spatial profiles of images generated using our proposed method. In addition, dynamic contrast-enhanced cardiovascular imaging of healthy subjects was performed to demonstrate the feasibility and advantages. The simulation results show that POBS VS-Prop can provide timely dynamic response to rapid signal change, especially for a small region of interest or with the use of narrow blades. The POBS algorithm also demonstrates its capability to capture nonsimultaneous signal changes over the entire FOV. In addition, both phantom and in vivo experiments show that the temporal smoothing effect can be avoided by means of POBS, leading to higher wash-in slope of contrast enhancement after the bolus injection. With the satisfactory reconstruction quality provided by the POBS algorithm, VS-Prop acquisition technique may find useful clinical applications in DCE MR imaging studies where both spatial and temporal resolutions play important roles.
Spotiton: A prototype for an integrated inkjet dispense and vitrification system for cryo-TEM
Jain, Tilak; Sheehan, Patrick; Crum, John; Carragher, Bridget; Potter, Clinton S.
2012-01-01
Over the last three decades, Cryo-TEM has developed into a powerful technique for high-resolution imaging of biological macromolecules in their native vitrified state. However, the technique for vitrifying specimens onto EM grids is essentially unchanged – application of ~ 3 µL sample to a grid, followed by blotting and rapid plunge freezing into liquid ethane. Several trials are often required to obtain suitable thin (few hundred nanometers or less) vitrified layers amenable for cryo-TEM imaging, which results in waste of precious sample and resources. While commercially available instruments provide some level of automation to control the vitrification process in an effort to increase quality and reproducibility, obtaining satisfactory vitrified specimens remains a bottleneck in the Cryo-TEM pipeline. We describe here a completely novel method for EM specimen preparation based on small volume (picoliter to nanoliter) dispensing using inkjet technology. A first prototype system (Spotiton v0.5) demonstrates feasibility of this new approach for specimen vitrification. A piezo-electric inkjet dispenser is integrated with optical real-time cameras (100 Hz frame rate) to analyze picoliter to nanoliter droplet profiles in-flight and spreading dynamics on the grid, and thus provides a method to optimize timing of the process. Using TEM imaging and biochemical assays we demonstrate that the piezo-electric inkjet mechanism does not disrupt the structural or functional integrity of macromolecules. These preliminary studies provide insight into the factors and components that will need further development to enable a robust and repeatable technique for specimen vitrification using this novel approach. PMID:22569522
“Anyone Know What Species This Is?” – Twitter Conversations as Embryonic Citizen Science Communities
Daume, Stefan; Galaz, Victor
2016-01-01
Social media like blogs, micro-blogs or social networks are increasingly being investigated and employed to detect and predict trends for not only social and physical phenomena, but also to capture environmental information. Here we argue that opportunistic biodiversity observations published through Twitter represent one promising and until now unexplored example of such data mining. As we elaborate, it can contribute to real-time information to traditional ecological monitoring programmes including those sourced via citizen science activities. Using Twitter data collected for a generic assessment of social media data in ecological monitoring we investigated a sample of what we denote biodiversity observations with species determination requests (N = 191). These entail images posted as messages on the micro-blog service Twitter. As we show, these frequently trigger conversations leading to taxonomic determinations of those observations. All analysed Tweets were posted with species determination requests, which generated replies for 64% of Tweets, 86% of those contained at least one suggested determination, of which 76% were assessed as correct. All posted observations included or linked to images with the overall image quality categorised as satisfactory or better for 81% of the sample and leading to taxonomic determinations at the species level in 71% of provided determinations. We claim that the original message authors and conversation participants can be viewed as implicit or embryonic citizen science communities which have to offer valuable contributions both as an opportunistic data source in ecological monitoring as well as potential active contributors to citizen science programmes. PMID:26967526
Layered compression for high-precision depth data.
Miao, Dan; Fu, Jingjing; Lu, Yan; Li, Shipeng; Chen, Chang Wen
2015-12-01
With the development of depth data acquisition technologies, access to high-precision depth with more than 8-b depths has become much easier and determining how to efficiently represent and compress high-precision depth is essential for practical depth storage and transmission systems. In this paper, we propose a layered high-precision depth compression framework based on an 8-b image/video encoder to achieve efficient compression with low complexity. Within this framework, considering the characteristics of the high-precision depth, a depth map is partitioned into two layers: 1) the most significant bits (MSBs) layer and 2) the least significant bits (LSBs) layer. The MSBs layer provides rough depth value distribution, while the LSBs layer records the details of the depth value variation. For the MSBs layer, an error-controllable pixel domain encoding scheme is proposed to exploit the data correlation of the general depth information with sharp edges and to guarantee the data format of LSBs layer is 8 b after taking the quantization error from MSBs layer. For the LSBs layer, standard 8-b image/video codec is leveraged to perform the compression. The experimental results demonstrate that the proposed coding scheme can achieve real-time depth compression with satisfactory reconstruction quality. Moreover, the compressed depth data generated from this scheme can achieve better performance in view synthesis and gesture recognition applications compared with the conventional coding schemes because of the error control algorithm.
Heterogeneous sharpness for cross-spectral face recognition
NASA Astrophysics Data System (ADS)
Cao, Zhicheng; Schmid, Natalia A.
2017-05-01
Matching images acquired in different electromagnetic bands remains a challenging problem. An example of this type of comparison is matching active or passive infrared (IR) against a gallery of visible face images, known as cross-spectral face recognition. Among many unsolved issues is the one of quality disparity of the heterogeneous images. Images acquired in different spectral bands are of unequal image quality due to distinct imaging mechanism, standoff distances, or imaging environment, etc. To reduce the effect of quality disparity on the recognition performance, one can manipulate images to either improve the quality of poor-quality images or to degrade the high-quality images to the level of the quality of their heterogeneous counterparts. To estimate the level of discrepancy in quality of two heterogeneous images a quality metric such as image sharpness is needed. It provides a guidance in how much quality improvement or degradation is appropriate. In this work we consider sharpness as a relative measure of heterogeneous image quality. We propose a generalized definition of sharpness by first achieving image quality parity and then finding and building a relationship between the image quality of two heterogeneous images. Therefore, the new sharpness metric is named heterogeneous sharpness. Image quality parity is achieved by experimentally finding the optimal cross-spectral face recognition performance where quality of the heterogeneous images is varied using a Gaussian smoothing function with different standard deviation. This relationship is established using two models; one of them involves a regression model and the other involves a neural network. To train, test and validate the model, we use composite operators developed in our lab to extract features from heterogeneous face images and use the sharpness metric to evaluate the face image quality within each band. Images from three different spectral bands visible light, near infrared, and short-wave infrared are considered in this work. Both error of a regression model and validation error of a neural network are analyzed.
A brain MRI bias field correction method created in the Gaussian multi-scale space
NASA Astrophysics Data System (ADS)
Chen, Mingsheng; Qin, Mingxin
2017-07-01
A pre-processing step is needed to correct for the bias field signal before submitting corrupted MR images to such image-processing algorithms. This study presents a new bias field correction method. The method creates a Gaussian multi-scale space by the convolution of the inhomogeneous MR image with a two-dimensional Gaussian function. In the multi-Gaussian space, the method retrieves the image details from the differentiation of the original image and convolution image. Then, it obtains an image whose inhomogeneity is eliminated by the weighted sum of image details in each layer in the space. Next, the bias field-corrected MR image is retrieved after the Υ correction, which enhances the contrast and brightness of the inhomogeneity-eliminated MR image. We have tested the approach on T1 MRI and T2 MRI with varying bias field levels and have achieved satisfactory results. Comparison experiments with popular software have demonstrated superior performance of the proposed method in terms of quantitative indices, especially an improvement in subsequent image segmentation.
NASA Technical Reports Server (NTRS)
Frost, Chad R.; Franklin, James A.; Hardy, Gordon H.
2002-01-01
A piloted simulation was performed on the Vertical Motion Simulator at NASA Ames Research Center to evaluate flying qualities of a tilt-wing Short Take-Off and Landing (STOL) transport aircraft during final approach and landing. The experiment was conducted to assess the design s handling qualities, and to evaluate the use of flightpath-centered guidance for the precision approach and landing tasks required to perform STOL operations in instrument meteorological conditions, turbulence, and wind. Pilots rated the handling qualities to be satisfactory for all operations evaluated except those encountering extreme crosswinds and severe windshear; even in these difficult meteorological conditions, adequate handling qualities were maintained. The advanced flight control laws and guidance displays provided consistent performance and precision landings.
A village-sclae trial with dichlorvos as a residual fumigant insecticide in southern Nigeria*
Gratz, N. G.; Bracha, P.; Carmichael, A.
1963-01-01
Hut and village-scale trials with solid and liquid-type dichlorvos dispensers were carried out in 1961 in the vicinity of Lagos, Nigeria, by the WHO Insecticide Testing Unit. Bioassay results indicated that with a single application satisfactory mortalities of caged mosquitos could be obtained for a period of 12-13 weeks in mud-walled huts, whether with galvanized corrugated-iron roofs or with thatched roofs. Chemical analysis of air samples showed that satisfactory concentrations of dichlorvos vapour were maintained throughout the huts for about 12 weeks, after which time sublethal concentrations were observed first near the floors of the dwellings. No depression in blood or plasma cholinesterase was noted in the exposed inhabitants ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5FIG. 6FIG. 7 PMID:14056280
USDA-ARS?s Scientific Manuscript database
Reciprocating grinders can grind single maize kernels by shaking the kernel in a vial with a ball bearing. This process results in a grind quality that is not satisfactory for many experiments. Tungesten carbide ball bearings are nearly twice as dense as steel, so we compared their grinding performa...
Linking log quality with product performance
D. W. Green; Robert Ross
1997-01-01
In the United States, log grading procedures use visual assessment of defects, in relation to the log scaling diameter, to estimate the yield of lumber that maybe expected from the log. This procedure was satisfactory when structural grades were based only on defect size and location. In recent years, however, structural products have increasingly been graded using a...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-23
... satisfactory quality] to the City for the purchase of ORION [supreg] Water Meter Monitor with Leak Detection... Leak Detection Indicator in-home water meter monitors manufactured in Malaysia by Escatech, Inc., under... conservation through the early detection and remediation of leaks. The City has used residential water meters...
7 CFR 58.346 - Whipped butter.
Code of Federal Regulations, 2010 CFR
2010-01-01
... count, not more than 50 per gram; yeast and mold count, not more than 10 per gram; coliform count, not more than 10 per gram; and keeping-quality test, satisfactory after 7 days at 72 °F. (2) Optional... ppm; enterococci, not more than 10 per gram. [59 FR 1264, Jan. 10, 1994, as amended at 67 FR 48976...
7 CFR 58.346 - Whipped butter.
Code of Federal Regulations, 2013 CFR
2013-01-01
... count, not more than 50 per gram; yeast and mold count, not more than 10 per gram; coliform count, not more than 10 per gram; and keeping-quality test, satisfactory after 7 days at 72 °F. (2) Optional... ppm; enterococci, not more than 10 per gram. [59 FR 1264, Jan. 10, 1994, as amended at 67 FR 48976...
7 CFR 58.346 - Whipped butter.
Code of Federal Regulations, 2011 CFR
2011-01-01
... count, not more than 50 per gram; yeast and mold count, not more than 10 per gram; coliform count, not more than 10 per gram; and keeping-quality test, satisfactory after 7 days at 72 °F. (2) Optional... ppm; enterococci, not more than 10 per gram. [59 FR 1264, Jan. 10, 1994, as amended at 67 FR 48976...
7 CFR 58.346 - Whipped butter.
Code of Federal Regulations, 2014 CFR
2014-01-01
... count, not more than 50 per gram; yeast and mold count, not more than 10 per gram; coliform count, not more than 10 per gram; and keeping-quality test, satisfactory after 7 days at 72 °F. (2) Optional... ppm; enterococci, not more than 10 per gram. [59 FR 1264, Jan. 10, 1994, as amended at 67 FR 48976...
7 CFR 58.346 - Whipped butter.
Code of Federal Regulations, 2012 CFR
2012-01-01
... count, not more than 50 per gram; yeast and mold count, not more than 10 per gram; coliform count, not more than 10 per gram; and keeping-quality test, satisfactory after 7 days at 72 °F. (2) Optional... ppm; enterococci, not more than 10 per gram. [59 FR 1264, Jan. 10, 1994, as amended at 67 FR 48976...
ERIC Educational Resources Information Center
Hill, Antonio
2011-01-01
Our nation's k-12 schools are faced with numerous critical challenges: elevating academic achievement, recruitment and retention of high-caliber teachers, improving teacher quality, and meeting the mandates of the "No Child Left Behind" ("NCLB") legislation and state standards (Simpson, Lacava, & Graner, 2004; &…
The Link between Higher Order Thinking Skills, Representation and Concepts in Enhancing TIMSS Tasks
ERIC Educational Resources Information Center
Tajudin, Nor'ain Mohd.; Chinnappan, Mohan
2016-01-01
Students' performances in TIMSS have featured strongly in recent discussions and debates about the quality of mathematical learning outcomes both from teachers and policy makers. Findings of TIMSS trends showed that most high school students in Malaysia continue to perform at less than satisfactory levels, particularly, in tasks that are…
Summary of the effects of engine throttle response on airplane formation-flying qualities
NASA Technical Reports Server (NTRS)
Walsh, Kevin R.
1992-01-01
A flight evaluation as conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented.
Hybrid procedure for orbital venous malformation in the endovascular operation room.
Cheng, A C O; Li, E Y M; Chan, T C Y; Wong, A C W; Chan, P C M; Poon, W W L; Fung, D H S; Yuen, H K L
2015-08-01
To describe a hybrid procedure for orbital venous malformation in the endovascular operating room (EVOR). Five consecutive patients with venous malformation in the periocular and orbital region were included. All patients received a one-stage direct puncture venogram, image-guided glue injection, and surgical resection in the EVOR equipped with a biplane digital subtraction angiography system (BDSAS). The mean age at the time of operation was 37.4 years (range, 22-69 years). The mean operative time was 193 min (range, 138-324 min). No intraoperative complications were noted. The mean follow-up duration was 18.8 months (range, 10-24 months). Three patients had complete removal of the vascular lesions. At the latest follow-up, no recurrence of symptoms related to the lesions was noted. All patients had an uneventful recovery and satisfactory outcome. The hybrid procedure of orbital venous malformation in the EVOR is a novel application in ophthalmology. It is a safe and well-controlled procedure with real-time high-quality BDSAS surveillance to facilitate surgical resection. Its success requires collaboration between the interventional radiologist, the surgeon, and the ophthalmologist.
Banitsas, Konstantinos A; Perakis, Konstantinos; Tachakra, Sapal; Koutsouris, Dimitrios
2006-01-01
We developed a mobile teleconsultation system based on third-generation mobile phone links. The system comprised a laptop computer and a digital camcorder. It was installed inside an ambulance to allow video-conferencing between the moving vehicle and a doctor at a base station. In addition to video and voice, high-quality still images could also be transmitted. A series of 17 trial runs with real ambulance patients was conducted in the city of Athens. In general, the videoconferencing sessions produced relatively clear video. The bandwidth was high enough for a satisfactory video of 10-15 frames/s. During a total testing period of 23 h and in an area of about 180 km2, there were nine instances of signal loss, amounting to a total of 17 min. The general opinion formed by the doctors was that the system produced good results. All initial diagnoses made using the system agreed with the final diagnoses of the patients. The study showed that the mobile system could reduce the time before an ambulance patient is seen by a doctor.
Factors affecting weld root morphology in laser keyhole welding
NASA Astrophysics Data System (ADS)
Frostevarg, Jan
2018-02-01
Welding production efficiency is usually optimised if full penetration can be achieved in a single pass. Techniques such as electron and laser beam welding offer deep high speed keyhole welding, especially since multi-kilowatt lasers became available. However, there are limitations for these techniques when considering weld imperfections such as weld cap undercuts, interior porosity or humps at the root. The thickness of sheets during full penetration welding is practically limited by these root humps. The mechanisms behind root morphology formation are not yet satisfactory understood. In this paper root humping is studied by reviewing previous studies and findings and also by sample examination and process observation by high speed imaging. Different process regimes governing root quality are presented, categorized and explained. Even though this study mainly covers laser beam and laser arc hybrid welding, the presented findings can generally be applied full penetration welding in medium to thick sheets, especially the discussion of surface tension effects. As a final result of this analysis, a map of methods to optimise weld root topology is presented.
Matsumoto, Yuji; Takaki, Yasuhiro
2014-06-15
Horizontally scanning holography can enlarge both screen size and viewing zone angle. A microelectromechanical-system spatial light modulator, which can generate only binary images, is used to generate hologram patterns. Thus, techniques to improve gray-scale representation in reconstructed images should be developed. In this study, the error diffusion technique was used for the binarization of holograms. When the Floyd-Steinberg error diffusion coefficients were used, gray-scale representation was improved. However, the linearity in the gray-scale representation was not satisfactory. We proposed the use of a correction table and showed that the linearity was greatly improved.
Remote Sensing Image Quality Assessment Experiment with Post-Processing
NASA Astrophysics Data System (ADS)
Jiang, W.; Chen, S.; Wang, X.; Huang, Q.; Shi, H.; Man, Y.
2018-04-01
This paper briefly describes the post-processing influence assessment experiment, the experiment includes three steps: the physical simulation, image processing, and image quality assessment. The physical simulation models sampled imaging system in laboratory, the imaging system parameters are tested, the digital image serving as image processing input are produced by this imaging system with the same imaging system parameters. The gathered optical sampled images with the tested imaging parameters are processed by 3 digital image processes, including calibration pre-processing, lossy compression with different compression ratio and image post-processing with different core. Image quality assessment method used is just noticeable difference (JND) subject assessment based on ISO20462, through subject assessment of the gathered and processing images, the influence of different imaging parameters and post-processing to image quality can be found. The six JND subject assessment experimental data can be validated each other. Main conclusions include: image post-processing can improve image quality; image post-processing can improve image quality even with lossy compression, image quality with higher compression ratio improves less than lower ratio; with our image post-processing method, image quality is better, when camera MTF being within a small range.
NASA Astrophysics Data System (ADS)
Vuori, Tero; Olkkonen, Maria
2006-01-01
The aim of the study is to test both customer image quality rating (subjective image quality) and physical measurement of user behavior (eye movements tracking) to find customer satisfaction differences in imaging technologies. Methodological aim is to find out whether eye movements could be quantitatively used in image quality preference studies. In general, we want to map objective or physically measurable image quality to subjective evaluations and eye movement data. We conducted a series of image quality tests, in which the test subjects evaluated image quality while we recorded their eye movements. Results show that eye movement parameters consistently change according to the instructions given to the user, and according to physical image quality, e.g. saccade duration increased with increasing blur. Results indicate that eye movement tracking could be used to differentiate image quality evaluation strategies that the users have. Results also show that eye movements would help mapping between technological and subjective image quality. Furthermore, these results give some empirical emphasis to top-down perception processes in image quality perception and evaluation by showing differences between perceptual processes in situations when cognitive task varies.
[Bacteriological quality of drinking water in the City of Merida, Mexico].
Flores-Abuxapqui, J J; Suárez-Hoil, G J; Puc-Franco, M A; Heredia-Navarrete, M R; Vivas-Rosel, M D; Franco-Monsreal, J
1995-01-01
With the aim of knowing the microbiological quality of drinking water in Merida, Yucatan, 383 paired samples of drinking water (two per house) were studied. Three hundred sixty four (95%) city water system samples and 283 (73.89%) tap water samples met the microbiological standards for drinking water. It was concluded that microbiological quality of drinking water from the city water system is satisfactory, except for the water system district Merida III, which has a significant aerobic plate count contamination level (21.7% of the samples). Domestic storage systems preserve water quality, with the exception of district Merida I, which has the highest level of contamination (4.8% of the samples) possibly from sewage water and fecal sources.
Lin, Chung-Ying; Yang, Szu-Chun; Lai, Wu-Wei; Su, Wu-Chou; Wang, Jung-Der
2017-03-01
The study examined whether the items of the World Health Organization Quality of Life-Brief questionnaire can assess its four underlying domains (Physical, Psychological, Social, and Environment) in a sample of lung cancer patients. All patients ( n = 1150) were recruited from a medical center in Tainan, and each participant completed the World Health Organization Quality of Life-Brief. Several Rasch rating scale models were used to examine the data-model fit, and Rasch analyses corroborated that each domain of the World Health Organization Quality of Life-Brief could be unidimensional. Although three items were found to have a poor fit, all the other items fit the unidimensionality with ordered thresholds.
Vining, Kevin C.; Cates, Steven W.
2006-01-01
Available surface-water quality, ground-water quality, and water-withdrawal data for the Spirit Lake Reservation were summarized. The data were collected intermittently from 1948 through 2004 and were compiled from U.S. Geological Survey databases, North Dakota State Water Commission databases, and Spirit Lake Nation tribal agencies. Although the quality of surface water on the reservation generally is satisfactory, no surface-water sources are used for consumable water supplies. Ground water on the reservation is of sufficient quality for most uses. The Tokio and Warwick aquifers have better overall water quality than the Spiritwood aquifer. Water from the Spiritwood aquifer is used mostly for irrigation. The Warwick aquifer provides most of the consumable water for the reservation and for the city of Devils Lake. Annual water withdrawals from the Warwick aquifer by the Spirit Lake Nation ranged from 71 million gallons to 122 million gallons during 2000-04.
Retrieving Coherent Receiver Function Images with Dense Arrays
NASA Astrophysics Data System (ADS)
Zhong, M.; Zhan, Z.
2016-12-01
Receiver functions highlight converted phases (e.g., Ps, PpPs, sP) and have been widely used to study seismic interfaces. With a dense array, receiver functions (RFs) at multiple stations form a RF image that can provide more robust/detailed constraints. However, due to noise in data, non-uniqueness of deconvolution, and local structures that cannot be detected across neighboring stations, traditional RF images are often noisy and hard to interpret. Previous attempts to enhance coherence by stacking RFs from multiple events or post-filtering the RF images have not produced satisfactory improvements. Here, we propose a new method to retrieve coherent RF images with dense arrays. We take advantage of the waveform coherency at neighboring stations and invert for a small number of coherent arrivals for their RFs. The new RF images contain only the coherent arrivals required to fit data well. Synthetic tests and preliminary applications on real data demonstrate that the new RF images are easier to interpret and improve our ability to infer Earth structures using receiver functions.
Robust and fast-converging level set method for side-scan sonar image segmentation
NASA Astrophysics Data System (ADS)
Liu, Yan; Li, Qingwu; Huo, Guanying
2017-11-01
A robust and fast-converging level set method is proposed for side-scan sonar (SSS) image segmentation. First, the noise in each sonar image is removed using the adaptive nonlinear complex diffusion filter. Second, k-means clustering is used to obtain the initial presegmentation image from the denoised image, and then the distance maps of the initial contours are reinitialized to guarantee the accuracy of the numerical calculation used in the level set evolution. Finally, the satisfactory segmentation is achieved using a robust variational level set model, where the evolution control parameters are generated by the presegmentation. The proposed method is successfully applied to both synthetic image with speckle noise and real SSS images. Experimental results show that the proposed method needs much less iteration and therefore is much faster than the fuzzy local information c-means clustering method, the level set method using a gamma observation model, and the enhanced region-scalable fitting method. Moreover, the proposed method can usually obtain more accurate segmentation results compared with other methods.
Crack image segmentation based on improved DBC method
NASA Astrophysics Data System (ADS)
Cao, Ting; Yang, Nan; Wang, Fengping; Gao, Ting; Wang, Weixing
2017-11-01
With the development of computer vision technology, crack detection based on digital image segmentation method arouses global attentions among researchers and transportation ministries. Since the crack always exhibits the random shape and complex texture, it is still a challenge to accomplish reliable crack detection results. Therefore, a novel crack image segmentation method based on fractal DBC (differential box counting) is introduced in this paper. The proposed method can estimate every pixel fractal feature based on neighborhood information which can consider the contribution from all possible direction in the related block. The block moves just one pixel every time so that it could cover all the pixels in the crack image. Unlike the classic DBC method which only describes fractal feature for the related region, this novel method can effectively achieve crack image segmentation according to the fractal feature of every pixel. The experiment proves the proposed method can achieve satisfactory results in crack detection.
Wilson, A J; Hodge, J C
1995-08-01
To evaluate the diagnostic performance of a teleradiology system in skeletal trauma. Radiographs from 180 skeletal trauma patients were digitized (matrix, 2,000 x 2,500) and transmitted to a remote digital viewing console (1,200-line monitor). Four radiologists interpreted both the original film images and digital images. Each reader was asked to identify, locate, and characterize fractures and dislocations. Receiver operating characteristic curves were generated, and the results of the original and digitized film readings were compared. All readers performed better with the original film when interpreting fractures. Although the patterns varied between readers, all had statistically significant differences (P < .01) for the two image types. There was no statistically significant difference in performance with the two images when dislocations were diagnosed. The system tested is not a satisfactory alternative to the original radiograph for routine reading of fracture films.
Automatic retinal interest evaluation system (ARIES).
Yin, Fengshou; Wong, Damon Wing Kee; Yow, Ai Ping; Lee, Beng Hai; Quan, Ying; Zhang, Zhuo; Gopalakrishnan, Kavitha; Li, Ruoying; Liu, Jiang
2014-01-01
In recent years, there has been increasing interest in the use of automatic computer-based systems for the detection of eye diseases such as glaucoma, age-related macular degeneration and diabetic retinopathy. However, in practice, retinal image quality is a big concern as automatic systems without consideration of degraded image quality will likely generate unreliable results. In this paper, an automatic retinal image quality assessment system (ARIES) is introduced to assess both image quality of the whole image and focal regions of interest. ARIES achieves 99.54% accuracy in distinguishing fundus images from other types of images through a retinal image identification step in a dataset of 35342 images. The system employs high level image quality measures (HIQM) to perform image quality assessment, and achieves areas under curve (AUCs) of 0.958 and 0.987 for whole image and optic disk region respectively in a testing dataset of 370 images. ARIES acts as a form of automatic quality control which ensures good quality images are used for processing, and can also be used to alert operators of poor quality images at the time of acquisition.
NASA Astrophysics Data System (ADS)
Chun, Wanhee; Do, Dukho; Gweon, Dae-Gab
2013-01-01
We developed a multimodal microscopy based on an optical scanning system in order to obtain diverse optical information of the same area of a sample. Multimodal imaging researches have mostly depended on a commercial microscope platform, easy to use but restrictive to extend imaging modalities. In this work, the beam scanning optics, especially including a relay lens, was customized to transfer broadband (400-1000 nm) lights to a sample without any optical error or loss. The customized scanning optics guarantees the best performances of imaging techniques utilizing the lights within the design wavelength. Confocal reflection, confocal fluorescence, and two-photon excitation fluorescence images were obtained, through respective implemented imaging channels, to demonstrate imaging feasibility for near-UV, visible, near-IR continuous light, and pulsed light in the scanning optics. The imaging performances for spatial resolution and image contrast were verified experimentally; the results were satisfactory in comparison with theoretical results. The advantages of customization, containing low cost, outstanding combining ability and diverse applications, will contribute to vitalize multimodal imaging researches.
Naturalness and interestingness of test images for visual quality evaluation
NASA Astrophysics Data System (ADS)
Halonen, Raisa; Westman, Stina; Oittinen, Pirkko
2011-01-01
Balanced and representative test images are needed to study perceived visual quality in various application domains. This study investigates naturalness and interestingness as image quality attributes in the context of test images. Taking a top-down approach we aim to find the dimensions which constitute naturalness and interestingness in test images and the relationship between these high-level quality attributes. We compare existing collections of test images (e.g. Sony sRGB images, ISO 12640 images, Kodak images, Nokia images and test images developed within our group) in an experiment combining quality sorting and structured interviews. Based on the data gathered we analyze the viewer-supplied criteria for naturalness and interestingness across image types, quality levels and judges. This study advances our understanding of subjective image quality criteria and enables the validation of current test images, furthering their development.
NASA Astrophysics Data System (ADS)
Nyman, G.; Häkkinen, J.; Koivisto, E.-M.; Leisti, T.; Lindroos, P.; Orenius, O.; Virtanen, T.; Vuori, T.
2010-01-01
Subjective image quality data for 9 image processing pipes and 8 image contents (taken with mobile phone camera, 72 natural scene test images altogether) from 14 test subjects were collected. A triplet comparison setup and a hybrid qualitative/quantitative methodology were applied. MOS data and spontaneous, subjective image quality attributes to each test image were recorded. The use of positive and negative image quality attributes by the experimental subjects suggested a significant difference between the subjective spaces of low and high image quality. The robustness of the attribute data was shown by correlating DMOS data of the test images against their corresponding, average subjective attribute vector length data. The findings demonstrate the information value of spontaneous, subjective image quality attributes in evaluating image quality at variable quality levels. We discuss the implications of these findings for the development of sensitive performance measures and methods in profiling image processing systems and their components, especially at high image quality levels.
Chen, T K; Chen, J N
2004-01-01
In TFT-LCD industry, water plays a variety of roles as a cleaning agent and reaction solvent. As good quality water is increasingly a scarce resource and wastewater treatment costs rises, the once-through use of industrial water is becoming uneconomical and environmentally unacceptable. Instead, recycling of TFT-LCD industrial wastewater is become more attractive from both an economic and environmental perspective. This research is mainly to explore the capacity of TFT-LCD industrial wastewater recycling by the process combined with membrane bioreactor and reverse osmosis processes. Over the whole experimental period, the MBR process achieved a satisfactory organic removal. The COD could be removed with an average of over 97.3%. For TOC and BOD5 items, the average removal efficiencies were 97.8 and 99.4% respectively. The stable effluent quality and satisfactory removal performance were ensured by the efficient interception performance of the UF membrane device incorporated with biological reactor. Moreover, the MBR effluent did not contain any suspended solids and the SDI value was under 3. After treatment of RO, excellent water quality of permeate were under 5 mg/l, 2.5 mg/l and 150 micros/cm for COD, TOC and conductivity respectively. The treated water can be recycled for the cooling tower make-up water or other purposes.
Results from a pediatric surgical centre justify early intervention in disorders of sex development.
Crawford, Jennifer M; Warne, Garry; Grover, Sonia; Southwell, Bridget R; Hutson, John M
2009-02-01
Controversy persists surrounding early management of disorders of sex development. We assessed genital appearance, gender identity, and quality of life in prepubertal children who have had early surgical intervention. Children treated for disorders of sex development who were 5 to 10 years of age were eligible (n = 54). Children were scored (modified Creighton scale) for anatomical and cosmetic outcome, and both patients and parents completed PedsQL quality-of-life and gender identity questionnaires, with ethics approval. Of 54 patients, 41 presented for review. Treatment began at 13.2 (1.8-250.1) months (median; range) and were reviewed at 7.5 +/- 2.1 (mean +/- SD) years of age. Nineteen were raised as girls and 22 as boys. Girls had good (85%) or satisfactory (15%) anatomical/cosmetic outcome, whereas 52% boys had good, 38% satisfactory, and 10% poor cosmetic outcomes. On gender identity questionnaire, boys scored 3.9 +/- 0.4 (mean +/- SD) and girls 3.6 +/- 0.5; 1 of 19 boys and 3 of 19 girls had lower scores, suggesting risk of gender identity disorder. Quality-of-life scores were 80+ for physical and 65 to 80 for psychosocial scores. Early intervention is generally associated with positive outcomes for patients and parents. Girls had better anatomical outcomes than boys, and gender dysphoria risks were low in both sexes.
Scheffers, Mia; van Duijn, Marijtje A. J.; Bosscher, Ruud J.; Wiersma, Durk; Schoevers, Robert A.; van Busschbach, Jooske T.
2017-01-01
Background Body image has implications for psychosocial functioning and quality of life and its disturbance is reported in a broad range of psychiatric disorders. In view of the lack of instruments in Dutch measuring body image as a broad concept, we set out to make an instrument available that reflects the multidimensional character of this construct by including more dimensions than physical appearance. The Dresden Körperbildfragebogen (DBIQ, Dresden Body Image Questionnaire) particularly served this purpose. The DBIQ consists of 35 items and five subscales: body acceptance, sexual fulfillment, physical contact, vitality, and self-aggrandizement. The main objective of the present study was to evaluate the psychometric properties of the Dutch translation of the Dresden Body Image Questionnaire (DBIQ-NL) in a non-clinical sample. Methods The psychometric properties of the DBIQ-NL were examined in a non-clinical sample of 988 respondents aged between 18 and 65. We investigated the subscales' internal consistency and test-retest reliability. In order to establish construct validity we evaluated the association with a related construct, body cathexis, and with indices of self-esteem and psychological wellbeing. The factor structure of the DBIQ-NL was examined via confirmatory factor analysis (CFA). The equivalence of the measurement model across sex and age was evaluated by multiplegroup confirmatory factor analyses. Results Confirmatory factor analyses showed a structure in accordance with the original scale, where model fit was improved significantly by moving one item to another subscale. Multiple group confirmatory factor analysis across sex and age demonstrated partial strong invariance. Internal consistency was good with little overlap between the subscales. Temporal reliability and construct validity were satisfactory. Conclusion Results indicate that the DBIQ-NL is a reliable and valid instrument for non-clinical subjects. This provides a sound basis for further investigation of the DBIQ-NL in a clinical sample. PMID:28746387
Zangger, Graziella; Zwisler, Ann-Dorthe; Kikkenborg Berg, Selina; Kristensen, Marie S; Grønset, Charlotte N; Uddin, Jamal; Pedersen, Susanne S; Oldridge, Neil B; Thygesen, Lau C
2018-01-01
Background Patient-reported health-related quality of life is increasingly used as an outcome measure in clinical trials and as a performance measure to evaluate quality of care. The objective of this study was to assess the psychometric properties of the Danish HeartQoL questionnaire, a core heart disease-specific health-related quality of life questionnaire, in implantable cardioverter defibrillator recipients. Design This study involved cross-sectional and test-retest study designs. Method Implantable cardioverter defibrillator recipients in the cross-sectional study completed the HeartQoL, the Short-Form 36 Health Survey, and the Hospital Anxiety and Depression Scale. The HeartQoL structure, construct-related validity (convergent and discriminative) and reliability (internal consistency) were assessed. HeartQoL reproducibility (test-retest) was assessed in an independent sample of implantable cardioverter defibrillator recipients. Results Mokken scale analysis supported the bi-dimensional structure of HeartQoL among 358 implantable cardioverter defibrillator recipients. Convergent ( r > 0.72) and discriminative validity were confirmed. The HeartQoL scales demonstrated satisfactory internal consistency (Cronbach's alpha > 0.90). Test-retest reliability (two weeks interval) was assessed in 89 implantable cardioverter defibrillator recipients and found to be acceptable for each scale (intra-class correlation > 0.90). Conclusion The Danish HeartQoL questionnaire demonstrated satisfactory key psychometric attributes of validity and reliability in this implantable cardioverter defibrillator population. This study adds support for the HeartQoL as a core heart-specific health-related quality of life questionnaire in a broad group of patients with heart disease including implantable cardioverter defibrillator recipients.
HYPERCALCURIA AND METABOLIC BONE DISEASE
Rosenberg, Milton L.
1954-01-01
Hypercalcuria leading to nephrocalcinosis and nephrolithiasis may be secondary to a number of causes. In most instances, the history, physical examination, a few simple laboratory tests and x-ray study of the bones will reveal the true primary diagnosis. Specific treatment, if instituted early, will result in a satisfactory response and prevent the progression of renal complications. ImagesFigure 1.Figure 2.Figure 3.Figure 4. PMID:13209371
Plastic spatula with narrow long tip provides higher satisfactory smears for Pap test.
Kaur, Pervinder; Kushtagi, Pralhad
2013-07-01
Ayre spatula for cervical smear collection is being used despite the suggestion that different modified spatulas provide more satisfactory sampling. To see whether the cytological pickup improves with the use of long tipped spatula. Rurally based University Hospital; crossover study. Pap smear using Ayre spatula in 500 and with plastic narrow long tip (Szalay) spatula in 500 clinic attending women was taken and analyzed. Crossover smears were taken with modified spatula in 163 and using Ayre spatula in 187 women after 2 weeks of initial smears. The same pathologist made cytological reporting for all smears and was unaware of the type of spatula used. Smears from Ayre spatula had significantly higher reports of inadequate smears (94 of 500 vs. 68 of 500 for Ayre and Szalay, respectively; P = 0.032) and it remained so even after crossover (94 of 187 vs. 70 of 163 for Ayre and Szalay, respectively; P = 0.2). Cellular quality appeared better with smears taken using Szalay spatula, but the overall abnormal smear detection rate remained similar with either collection tool (χ(2) = 1.5; P = 0.2). Proportion of satisfactory smears is higher when long tip plastic spatula is used for collection of sample.
Estimating Missing Features to Improve Multimedia Information Retrieval
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bagherjeiran, A; Love, N S; Kamath, C
Retrieval in a multimedia database usually involves combining information from different modalities of data, such as text and images. However, all modalities of the data may not be available to form the query. The retrieval results from such a partial query are often less than satisfactory. In this paper, we present an approach to complete a partial query by estimating the missing features in the query. Our experiments with a database of images and their associated captions show that, with an initial text-only query, our completion method has similar performance to a full query with both image and text features.more » In addition, when we use relevance feedback, our approach outperforms the results obtained using a full query.« less
Noise Estimation and Quality Assessment of Gaussian Noise Corrupted Images
NASA Astrophysics Data System (ADS)
Kamble, V. M.; Bhurchandi, K.
2018-03-01
Evaluating the exact quantity of noise present in an image and quality of an image in the absence of reference image is a challenging task. We propose a near perfect noise estimation method and a no reference image quality assessment method for images corrupted by Gaussian noise. The proposed methods obtain initial estimate of noise standard deviation present in an image using the median of wavelet transform coefficients and then obtains a near to exact estimate using curve fitting. The proposed noise estimation method provides the estimate of noise within average error of +/-4%. For quality assessment, this noise estimate is mapped to fit the Differential Mean Opinion Score (DMOS) using a nonlinear function. The proposed methods require minimum training and yields the noise estimate and image quality score. Images from Laboratory for image and Video Processing (LIVE) database and Computational Perception and Image Quality (CSIQ) database are used for validation of the proposed quality assessment method. Experimental results show that the performance of proposed quality assessment method is at par with the existing no reference image quality assessment metric for Gaussian noise corrupted images.
Ma, Ling; Liu, Xiabi; Gao, Yan; Zhao, Yanfeng; Zhao, Xinming; Zhou, Chunwu
2017-02-01
This paper proposes a new method of content based medical image retrieval through considering fused, context-sensitive similarity. Firstly, we fuse the semantic and visual similarities between the query image and each image in the database as their pairwise similarities. Then, we construct a weighted graph whose nodes represent the images and edges measure their pairwise similarities. By using the shortest path algorithm over the weighted graph, we obtain a new similarity measure, context-sensitive similarity measure, between the query image and each database image to complete the retrieval process. Actually, we use the fused pairwise similarity to narrow down the semantic gap for obtaining a more accurate pairwise similarity measure, and spread it on the intrinsic data manifold to achieve the context-sensitive similarity for a better retrieval performance. The proposed method has been evaluated on the retrieval of the Common CT Imaging Signs of Lung Diseases (CISLs) and achieved not only better retrieval results but also the satisfactory computation efficiency. Copyright © 2017 Elsevier Inc. All rights reserved.
Endo, Iara C; Ziegelmann, Patricia K; Patel, Anita
2016-12-07
Dengue fever is one of the most rapidly advancing viral vector-borne diseases worldwide and vaccine candidates are in the final stages of clinical trials, representing a decisive opportunity to control the disease. To decide whether and where to support the introduction of new vaccines it is crucial to assess costs imposed by the disease and cost-effectiveness of vaccine programmes. To identify economic evidence about dengue fever immunization, by systematic review, to assist future policy decisions and investment. The electronic search stage was conducted on PubMed/Medline, Embase, Web of Science, Global Health, NHS Economic Evaluation Database (NHS EED) and Latin American and Caribbean Health Sciences Literature (LILACS) databases. Searches were restricted to papers published between January 1970 and February 2016. Selected papers were quality assessed using three recognized checklists. Eleven relevant studies were identified and there is economic evidence of a satisfactory quality level, derived through modelling approaches, to conclude that dengue fever vaccines will be economically advantageous when compared to vector preventive strategies, despite uncertainties surrounding vaccine efficacy and costs per vaccine dose. Quality assessment based on checklists showed similar findings and although overall quality was considered satisfactory, there were relevant methodological issues not considered among studies reviewed. Several uncertainties still remain about effectiveness of dengue fever vaccines; however, the reviewed economic evidence suggests that, when available, the vaccine can be economically advantageous at moderate prices. Future research needs to confirm findings from the economic models by using actual costs and effectiveness data. Copyright © 2016 Elsevier Ltd. All rights reserved.
Technical proficiency in cytopathology: assessment through external quality assurance.
Cummings, M C; Greaves, J; Shukor, R A; Perkins, G; Ross, J
2017-04-01
To assess both the feasibility and value of conducting an external quality assurance programme concerning technical aspects of cytopathology laboratory practice, and the interest by laboratories in enrolling in such a programme. Six technical surveys, comprising staining exercises and questionnaires relating to laboratory practice, were distributed over a 4-year period to the approximately 220 laboratories enrolled in the RCPAQAP Cytopathology slide survey modules. Staining exercises using the Papanicolaou and Romanowsky techniques, the preparation of urine and body fluid specimens and immunocytochemistry on the cell block material were assessed. Accompanying relevant questionnaires were included, and one survey comprised a questionnaire alone concerning the collection of urinary tract and body fluid samples. Provision of an external cytopathology technical module was feasible for the RCPAQAP and participation rates (maximum of 87% per survey; average 68% for stained slides and 66% for questionnaires) were commendable, particularly considering these were optional undertakings with some exercises not applicable to all laboratories. The great majority of submitted slides were scored as satisfactory, and there was an especially high standard for the immunocytochemical staining exercise with 95% considered satisfactory, including 50.6% with a perfect score. Reasons for suboptimal scores were provided for potential quality improvement for interested laboratories. A wealth of information relating to laboratory practice was provided to the RCPAQAP which was collated and summarised for laboratory use. The provision of a technical module in cytopathology is both a feasible and valuable undertaking of interest to laboratories which should become standard practice for cytopathology external quality assurance providers. © 2016 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Brewer, Hannah; Rieg, Sue
2013-01-01
Although an abundant body of research demonstrates the need for quality health and physical education and reveals the innumerable benefits optimal health has on both physical and cognitive development, the number of preschools offering structured health and physical education programs is less than satisfactory [National Policy and Legal Analysis…
Instructional Sensitivity Statistics Appropriate for Objectives-Based Test Items. CSE Report No. 91.
ERIC Educational Resources Information Center
Kosecoff, Jacqueline B.; Klein, Stephen P.
Two types of sensitivity indices were developed in this paper, one internal to the total test and the second external. To evaluate the success of these statistics the three criteria suggested for a satisfactory index of item quality were considered. The Internal Sensitivity Index appears to meet these demands. Certainly it is easily computed. In…
A portable, low-cost flight-data measurement and recording system
NASA Technical Reports Server (NTRS)
Miller, R. J.
1982-01-01
The design of and the experience with an inexpensive, hand-portable, onboard data system used to record four parameters in the final portion of the landing approach and touchdown of an airplane are described. The system utilized a high-quality audio tape recorder and amateur photographic equipment with accessory circuitry rather than specialized instrumentation to given satisfactory results.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-25
... the purchase of a foreign manufactured 50 kW wind turbine generator that meets the Borough's design... manufactured 50 kW wind turbines available in sufficient and reasonable quantity and of a satisfactory quality... action permits the purchase of a foreign manufactured 50 kW wind turbine generator by the Borough, as...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-07
... ENVIRONMENTAL PROTECTION AGENCY [FRL-9145-4] Notice of a Project Waiver of Section 1605 (Buy... granting a project waiver of the Buy American requirements of ARRA Section 1605 under the authority of Section 1605(b)(2) [manufactured goods are not produced in the United States of a satisfactory quality] to...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-07
... ENVIRONMENTAL PROTECTION AGENCY [FRL-9145-6] Notice of a Project Waiver of Section 1605 (Buy... granting a project waiver of the Buy American requirements of ARRA Section 1605 under the authority of Section 1605(b)(2) [manufactured goods are not produced in the United States of a satisfactory quality] to...
Planting trials of 10 Mexican pine species in Hawaii
Craig D. Whitesell
1974-01-01
Ten species of Mexican pines were planted on adverse sites at 6450 feet (1970 m) elevation on Maui, and five species on similar sites at 3200 feet (975 m) elevation on Molokai, Hawaii. Initial survival was poor because of the low quality of the planting stock and harsh site conditions, but subsequent mortality was low. Growth and vigor has been satisfactory. Average...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-12
... goods are not produced in the United States in sufficient and reasonably available quantities and of a satisfactory quality] to the Utility for the purchase of a magnetic flow meter, manufactured in Mexico. This is... waiver based on project specific circumstances. The waiver applicant states that the project requires the...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seibert, J; Imbergamo, P
The expansion and integration of diagnostic imaging technologies such as On Board Imaging (OBI) and Cone Beam Computed Tomography (CBCT) into radiation oncology has required radiation oncology physicists to be responsible for and become familiar with assessing image quality. Unfortunately many radiation oncology physicists have had little or no training or experience in measuring and assessing image quality. Many physicists have turned to automated QA analysis software without having a fundamental understanding of image quality measures. This session will review the basic image quality measures of imaging technologies used in the radiation oncology clinic, such as low contrast resolution, highmore » contrast resolution, uniformity, noise, and contrast scale, and how to measure and assess them in a meaningful way. Additionally a discussion of the implementation of an image quality assurance program in compliance with Task Group recommendations will be presented along with the advantages and disadvantages of automated analysis methods. Learning Objectives: Review and understanding of the fundamentals of image quality. Review and understanding of the basic image quality measures of imaging modalities used in the radiation oncology clinic. Understand how to implement an image quality assurance program and to assess basic image quality measures in a meaningful way.« less
Preliminary Investigation of the Flying Qualities of Airplanes
NASA Technical Reports Server (NTRS)
Soule, H A
1940-01-01
The National Advisory Committee for Aeronautics is undertaking an investigation of the flying qualities of airplanes. The work consists in the determination of the significant qualities susceptible of measurement, the development of the instruments required to make the measurements, and the accumulation of data on the flying qualities of existing airplanes, which data are to serve as a basis for quantitative specifications for the flying qualities of future designs. A tentative schedule of measurable flying qualities has been prepared and the instruments needed for their measurements have been assembled. A trial of the schedule and the instruments has been made using the Stinson SR-8e airplane. The results showed that, although the original schedule and instruments are basically satisfactory some further development is required to eliminate nonessential items and to expedite flight testing. The report describes and discusses the work done with this airplane.
Automatic comic page image understanding based on edge segment analysis
NASA Astrophysics Data System (ADS)
Liu, Dong; Wang, Yongtao; Tang, Zhi; Li, Luyuan; Gao, Liangcai
2013-12-01
Comic page image understanding aims to analyse the layout of the comic page images by detecting the storyboards and identifying the reading order automatically. It is the key technique to produce the digital comic documents suitable for reading on mobile devices. In this paper, we propose a novel comic page image understanding method based on edge segment analysis. First, we propose an efficient edge point chaining method to extract Canny edge segments (i.e., contiguous chains of Canny edge points) from the input comic page image; second, we propose a top-down scheme to detect line segments within each obtained edge segment; third, we develop a novel method to detect the storyboards by selecting the border lines and further identify the reading order of these storyboards. The proposed method is performed on a data set consisting of 2000 comic page images from ten printed comic series. The experimental results demonstrate that the proposed method achieves satisfactory results on different comics and outperforms the existing methods.
The effect of image quality, repeated study, and assessment method on anatomy learning.
Fenesi, Barbara; Mackinnon, Chelsea; Cheng, Lucia; Kim, Joseph A; Wainman, Bruce C
2017-06-01
The use of two-dimensional (2D) images is consistently used to prepare anatomy students for handling real specimen. This study examined whether the quality of 2D images is a critical component in anatomy learning. The visual clarity and consistency of 2D anatomical images was systematically manipulated to produce low-quality and high-quality images of the human hand and human eye. On day 0, participants learned about each anatomical specimen from paper booklets using either low-quality or high-quality images, and then completed a comprehension test using either 2D images or three-dimensional (3D) cadaveric specimens. On day 1, participants relearned each booklet, and on day 2 participants completed a final comprehension test using either 2D images or 3D cadaveric specimens. The effect of image quality on learning varied according to anatomical content, with high-quality images having a greater effect on improving learning of hand anatomy than eye anatomy (high-quality vs. low-quality for hand anatomy P = 0.018; high-quality vs. low-quality for eye anatomy P = 0.247). Also, the benefit of high-quality images on hand anatomy learning was restricted to performance on short-answer (SA) questions immediately after learning (high-quality vs. low-quality on SA questions P = 0.018), but did not apply to performance on multiple-choice (MC) questions (high-quality vs. low-quality on MC questions P = 0.109) or after participants had an additional learning opportunity (24 hours later) with anatomy content (high vs. low on SA questions P = 0.643). This study underscores the limited impact of image quality on anatomy learning, and questions whether investment in enhancing image quality of learning aids significantly promotes knowledge development. Anat Sci Educ 10: 249-261. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.
Clinical image quality evaluation for panoramic radiography in Korean dental clinics
Choi, Bo-Ram; Choi, Da-Hye; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Choi, Soon-Chul; Bae, Kwang-Hak
2012-01-01
Purpose The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Materials and Methods Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. Results A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Conclusion Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively. PMID:23071969
The study of surgical image quality evaluation system by subjective quality factor method
NASA Astrophysics Data System (ADS)
Zhang, Jian J.; Xuan, Jason R.; Yang, Xirong; Yu, Honggang; Koullick, Edouard
2016-03-01
GreenLightTM procedure is an effective and economical way of treatment of benign prostate hyperplasia (BPH); there are almost a million of patients treated with GreenLightTM worldwide. During the surgical procedure, the surgeon or physician will rely on the monitoring video system to survey and confirm the surgical progress. There are a few obstructions that could greatly affect the image quality of the monitoring video, like laser glare by the tissue and body fluid, air bubbles and debris generated by tissue evaporation, and bleeding, just to name a few. In order to improve the physician's visual experience of a laser surgical procedure, the system performance parameter related to image quality needs to be well defined. However, since image quality is the integrated set of perceptions of the overall degree of excellence of an image, or in other words, image quality is the perceptually weighted combination of significant attributes (contrast, graininess …) of an image when considered in its marketplace or application, there is no standard definition on overall image or video quality especially for the no-reference case (without a standard chart as reference). In this study, Subjective Quality Factor (SQF) and acutance are used for no-reference image quality evaluation. Basic image quality parameters, like sharpness, color accuracy, size of obstruction and transmission of obstruction, are used as subparameter to define the rating scale for image quality evaluation or comparison. Sample image groups were evaluated by human observers according to the rating scale. Surveys of physician groups were also conducted with lab generated sample videos. The study shows that human subjective perception is a trustworthy way of image quality evaluation. More systematic investigation on the relationship between video quality and image quality of each frame will be conducted as a future study.
Douglas, Pamela; Iskandrian, Ami E; Krumholz, Harlan M; Gillam, Linda; Hendel, Robert; Jollis, James; Peterson, Eric; Chen, Jersey; Masoudi, Frederick; Mohler, Emile; McNamara, Robert L; Patel, Manesh R; Spertus, John
2006-11-21
Cardiovascular imaging has enjoyed both rapid technological advances and sustained growth, yet less attention has been focused on quality than in other areas of cardiovascular medicine. To address this deficit, representatives from cardiovascular imaging societies, private payers, government agencies, the medical imaging industry, and experts in quality measurement met, and this report provides an overview of the discussions. A consensus definition of quality in imaging and a convergence of opinion on quality measures across imaging modalities was achieved and are intended to be the start of a process culminating in the development, dissemination, and adoption of quality measures for all cardiovascular imaging modalities.
Spatial-Spectral Approaches to Edge Detection in Hyperspectral Remote Sensing
NASA Astrophysics Data System (ADS)
Cox, Cary M.
This dissertation advances geoinformation science at the intersection of hyperspectral remote sensing and edge detection methods. A relatively new phenomenology among its remote sensing peers, hyperspectral imagery (HSI) comprises only about 7% of all remote sensing research - there are five times as many radar-focused peer reviewed journal articles than hyperspectral-focused peer reviewed journal articles. Similarly, edge detection studies comprise only about 8% of image processing research, most of which is dedicated to image processing techniques most closely associated with end results, such as image classification and feature extraction. Given the centrality of edge detection to mapping, that most important of geographic functions, improving the collective understanding of hyperspectral imagery edge detection methods constitutes a research objective aligned to the heart of geoinformation sciences. Consequently, this dissertation endeavors to narrow the HSI edge detection research gap by advancing three HSI edge detection methods designed to leverage HSI's unique chemical identification capabilities in pursuit of generating accurate, high-quality edge planes. The Di Zenzo-based gradient edge detection algorithm, an innovative version of the Resmini HySPADE edge detection algorithm and a level set-based edge detection algorithm are tested against 15 traditional and non-traditional HSI datasets spanning a range of HSI data configurations, spectral resolutions, spatial resolutions, bandpasses and applications. This study empirically measures algorithm performance against Dr. John Canny's six criteria for a good edge operator: false positives, false negatives, localization, single-point response, robustness to noise and unbroken edges. The end state is a suite of spatial-spectral edge detection algorithms that produce satisfactory edge results against a range of hyperspectral data types applicable to a diverse set of earth remote sensing applications. This work also explores the concept of an edge within hyperspectral space, the relative importance of spatial and spectral resolutions as they pertain to HSI edge detection and how effectively compressed HSI data improves edge detection results. The HSI edge detection experiments yielded valuable insights into the algorithms' strengths, weaknesses and optimal alignment to remote sensing applications. The gradient-based edge operator produced strong edge planes across a range of evaluation measures and applications, particularly with respect to false negatives, unbroken edges, urban mapping, vegetation mapping and oil spill mapping applications. False positives and uncompressed HSI data presented occasional challenges to the algorithm. The HySPADE edge operator produced satisfactory results with respect to localization, single-point response, oil spill mapping and trace chemical detection, and was challenged by false positives, declining spectral resolution and vegetation mapping applications. The level set edge detector produced high-quality edge planes for most tests and demonstrated strong performance with respect to false positives, single-point response, oil spill mapping and mineral mapping. False negatives were a regular challenge for the level set edge detection algorithm. Finally, HSI data optimized for spectral information compression and noise was shown to improve edge detection performance across all three algorithms, while the gradient-based algorithm and HySPADE demonstrated significant robustness to declining spectral and spatial resolutions.
Blind image quality assessment without training on human opinion scores
NASA Astrophysics Data System (ADS)
Mittal, Anish; Soundararajan, Rajiv; Muralidhar, Gautam S.; Bovik, Alan C.; Ghosh, Joydeep
2013-03-01
We propose a family of image quality assessment (IQA) models based on natural scene statistics (NSS), that can predict the subjective quality of a distorted image without reference to a corresponding distortionless image, and without any training results on human opinion scores of distorted images. These `completely blind' models compete well with standard non-blind image quality indices in terms of subjective predictive performance when tested on the large publicly available `LIVE' Image Quality database.
JPEG2000 still image coding quality.
Chen, Tzong-Jer; Lin, Sheng-Chieh; Lin, You-Chen; Cheng, Ren-Gui; Lin, Li-Hui; Wu, Wei
2013-10-01
This work demonstrates the image qualities between two popular JPEG2000 programs. Two medical image compression algorithms are both coded using JPEG2000, but they are different regarding the interface, convenience, speed of computation, and their characteristic options influenced by the encoder, quantization, tiling, etc. The differences in image quality and compression ratio are also affected by the modality and compression algorithm implementation. Do they provide the same quality? The qualities of compressed medical images from two image compression programs named Apollo and JJ2000 were evaluated extensively using objective metrics. These algorithms were applied to three medical image modalities at various compression ratios ranging from 10:1 to 100:1. Following that, the quality of the reconstructed images was evaluated using five objective metrics. The Spearman rank correlation coefficients were measured under every metric in the two programs. We found that JJ2000 and Apollo exhibited indistinguishable image quality for all images evaluated using the above five metrics (r > 0.98, p < 0.001). It can be concluded that the image quality of the JJ2000 and Apollo algorithms is statistically equivalent for medical image compression.
Kopchak, V M; Khomiak, I V; Cheverdiuk, D A; Kopchak, K V; Duvalko, A V; Serdiuk, V P
2012-01-01
An analysis of treatment of 584 patients with complicated forms of chronic pancreatitis operated during 2000-2100 years was carried out. Quality of life of postoperative patients was estimated according to a technique of calculations of modules EORTC QLQ-C30 and EORTC QLQ-PAN26. The indicators of quality of life have improved by 19.7% in performance of saving duodenal outflow of operations of pancreatic juice. Change of the surgical strategy has led to decreased number of postoperative complications by 4.6% and to satisfactory long-term results in 92.6% of the patients.
Vukmirović, D; Fišteš, A; Lević, J; Čolović, R; Rakić, D; Brlek, T; Banjac, V
2017-10-01
Poultry diets are mainly used in pelleted form because pellets have many advantages compared to mash feed. On the other hand, pelleting causes reduction of feed particle size. The aim of this research was to investigate the possibility of increasing the content of coarse particles in pellets, and, at the same time, to produce pellets with satisfactory quality. In this research, the three grinding treatments of corn were applied using hammer mill with three sieve openings diameter: 3 mm (HM-3), 6 mm (HM-6) and 9 mm (HM-9). These grinding treatments were combined in pelleting process with three gaps between rollers and the die of pellet press (roller-die gap, RDG) (0.30, 1.15 and 2.00 mm) and three moisture contents of the pelleted material (14.5, 16.0 and 17.5%). The increased coarseness of grinding by the hammer mill resulted in the increased amount of coarse particles in pellets, especially when the smallest RDG was applied (0.30 mm), but pellet quality was greatly reduced. Increasing of RDG improved the quality of pellets produced from coarsely ground corn, but reduced the content of coarse particles in pellets and increased specific energy consumption of the pellet press. Increasing the moisture content of material to be pelleted (MC) significantly reduced energy consumption of the pellet press, but there was no significant influence of MC on particle size after pelleting and on the pellet quality. The optimal values of the pelleting process parameters were determined using desirability function method. The results of optimization process showed that to achieve the highest possible quantity of coarse particles in the pellets, and to produce pellets of satisfactory quality, with the lowest possible energy consumption of the pellet press, the coarsest grinding on hammer mill (HM-9), the largest RDG (2 mm) and the highest MC (17.5%) should be applied. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.
Haidar, Rachid K; Kassak, Kassem; Masrouha, Karim; Ibrahim, Kamal; Mhaidli, Hani
2015-09-01
Cross-sectional validation and reliability assessment study of Arabic version of Scoliosis Research Society-22 (SRS-22r) Questionnaire. To develop and validate the Arabic version of the SRS-22r questionnaire. The diagnosis and treatment of adolescent idiopathic scoliosis may influence patient quality of life. SRS-22r is an internationally validated questionnaire used to assess function/activity, pain, self-image, and mental health of patients with scoliosis. It has been translated into several languages but not into Arabic language. Therefore, a valid health-related quality-of-life outcome questionnaire for patients with spinal deformity is still lacking in Arabic language. The English version of SRS-22r questionnaire was translated, back-translated, and culturally adapted to Arabic language. Then, 81 patients with idiopathic adolescent scoliosis were allocated randomly into either the reliability testing group (group 1) or the validity testing group (group 2). Group 1 patients completed Arabic version of SRS-22r questionnaire twice with 1-week interval in-between. Cronbach α and intraclass correlation coefficient were measured to determine internal consistency and temporal reliability. Group 2 patients completed the Arabic version of SRS-22r questionnaire and the previously validated Arabic version of 36-Item Short Form Health Survey (Short Form-36) questionnaire concurrently, and Pearson correlation coefficient was obtained to assess validity. Content analysis, internal consistency reliability, test/retest reproducibility (intraclass correlation coefficient range: 0.82-0.90), and test of concurrent validity showed satisfactory results. Function/activity and satisfaction with management domains had a lower Cronbach α (0.58 and 0.44, respectively, vs. 0.71-0.85 range for others). Self-image/appearance and satisfaction with management had a lower correlation with domains of the 36-Item Short Form Health Survey. An Arabic version of the SRS-22r questionnaire has been developed and validated. This questionnaire will aid health care workers and researchers in evaluation of patient perception of the deformity, satisfaction with treatment, and quality of life in Arabic-speaking populations. 3.
Blind image quality assessment based on aesthetic and statistical quality-aware features
NASA Astrophysics Data System (ADS)
Jenadeleh, Mohsen; Masaeli, Mohammad Masood; Moghaddam, Mohsen Ebrahimi
2017-07-01
The main goal of image quality assessment (IQA) methods is the emulation of human perceptual image quality judgments. Therefore, the correlation between objective scores of these methods with human perceptual scores is considered as their performance metric. Human judgment of the image quality implicitly includes many factors when assessing perceptual image qualities such as aesthetics, semantics, context, and various types of visual distortions. The main idea of this paper is to use a host of features that are commonly employed in image aesthetics assessment in order to improve blind image quality assessment (BIQA) methods accuracy. We propose an approach that enriches the features of BIQA methods by integrating a host of aesthetics image features with the features of natural image statistics derived from multiple domains. The proposed features have been used for augmenting five different state-of-the-art BIQA methods, which use statistical natural scene statistics features. Experiments were performed on seven benchmark image quality databases. The experimental results showed significant improvement of the accuracy of the methods.
Ernst, E J; Speck, Patricia M; Fitzpatrick, Joyce J
2011-12-01
With the patient's consent, physical injuries sustained in a sexual assault are evaluated and treated by the sexual assault nurse examiner (SANE) and documented on preprinted traumagrams and with photographs. Digital imaging is now available to the SANE for documentation of sexual assault injuries, but studies of the image quality of forensic digital imaging of female genital injuries after sexual assault were not found in the literature. The Photo Documentation Image Quality Scoring System (PDIQSS) was developed to rate the image quality of digital photo documentation of female genital injuries after sexual assault. Three expert observers performed evaluations on 30 separate images at two points in time. An image quality score, the sum of eight integral technical and anatomical attributes on the PDIQSS, was obtained for each image. Individual image quality ratings, defined by rating image quality for each of the data, were also determined. The results demonstrated a high level of image quality and agreement when measured in all dimensions. For the SANE in clinical practice, the results of this study indicate that a high degree of agreement exists between expert observers when using the PDIQSS to rate image quality of individual digital photographs of female genital injuries after sexual assault. © 2011 International Association of Forensic Nurses.
Fundamental studies of coal liquefaction. Quarterly report No. 7, April 1--July 1, 1993
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ross, D.S.
1993-07-14
In our last report we discussed observations in our cell concerning the behavior or Illinois No. 6 coal in tetralin to 460{degrees}C. We noted that there were possibly two distinct types of particles comprising the organic phase, reacting respectively at 420{degrees}--430{degrees}C, and at 450{degrees}--460{degrees}C. Alternatively we could interpret the data as describing a range of reactivity bounded by those temperatures. As evidenced by the contraction of the particles, the reactions were rapid. The particles lost half of their substance within 1 min, and we suggested that the rates were too fast to be accommodated by the commonly held scheme formore » coal liquefaction involving thermolytic scission of weak, bibenzyl-like bonds. Our analyses were aided by our use of Adobe Photoshop, which allows us to store, digitized versions of our recorded images. The images can then be manipulated at will to provide quantitative data on morphological changes. We noted in our last report that printer limitations prevented us from presenting images with the desirable quality, and we are at present attempting to find access to equipment which will provide satisfactory figures. Accordingly our progress will be described here without any photographs, and we expect to present a more complete account of our work in our next report. The work reported here includes studies of Illinois No. 6 coal with water as the medium, and a control run with argon as medium. Our temperature ramping was like that used last time, 25{degrees}C/min to 250{degrees}C, and then 10{degrees}C/min to 450{degrees}C. The results from the earlier work and the data presented here can therefore be directly compared.« less
Image aesthetic quality evaluation using convolution neural network embedded learning
NASA Astrophysics Data System (ADS)
Li, Yu-xin; Pu, Yuan-yuan; Xu, Dan; Qian, Wen-hua; Wang, Li-peng
2017-11-01
A way of embedded learning convolution neural network (ELCNN) based on the image content is proposed to evaluate the image aesthetic quality in this paper. Our approach can not only solve the problem of small-scale data but also score the image aesthetic quality. First, we chose Alexnet and VGG_S to compare for confirming which is more suitable for this image aesthetic quality evaluation task. Second, to further boost the image aesthetic quality classification performance, we employ the image content to train aesthetic quality classification models. But the training samples become smaller and only using once fine-tuning cannot make full use of the small-scale data set. Third, to solve the problem in second step, a way of using twice fine-tuning continually based on the aesthetic quality label and content label respective is proposed, the classification probability of the trained CNN models is used to evaluate the image aesthetic quality. The experiments are carried on the small-scale data set of Photo Quality. The experiment results show that the classification accuracy rates of our approach are higher than the existing image aesthetic quality evaluation approaches.
Desai, Nandini J.; Gupta, B. D.; Patel, Pratik Narendrabhai
2014-01-01
Introduction: Obtaining images of slides viewed by a microscope can be invaluable for both diagnosis and teaching.They can be transferred among technologically-advanced hospitals for further consultation and evaluation. But a standard microscopic photography camera unit (MPCU)(MIPS-Microscopic Image projection System) is costly and not available in resource poor settings. The aim of our endeavour was to find a comparable and cheaper alternative method for photomicrography. Materials and Methods: We used a NIKON Coolpix S6150 camera (box type digital camera) with Olympus CH20i microscope and a fluorescent microscope for the purpose of this study. Results: We got comparable results for capturing images of light microscopy, but the results were not as satisfactory for fluorescent microscopy. Conclusion: A box type digital camera is a comparable, less expensive and convenient alternative to microscopic photography camera unit. PMID:25478350
Design considerations for imaging charge-coupled device
NASA Astrophysics Data System (ADS)
1981-04-01
The image dissector tube, which was formerly used as detector in star trackers, will be replaced by solid state imaging devices. The technology advances of charge transfer devices, like the charge-coupled device (CCD) and the charge-injection device (CID) have made their application to star trackers an immediate reality. The Air Force in 1979 funded an American Aerospace company to develop an imaging CCD (ICCD) star sensor for the Multimission Attitude Determination and Autonomous Navigation (MADAN) system. The MADAN system is a technology development for a strapdown attitude and navigation system which can be used on all Air Force 3-axis stabilized satellites. The system will be autonomous and will provide real-time satellite attitude and position information. The star sensor accuracy provides an overall MADAN attitude accuracy of 2 arcsec for star rates up to 300 arcsec/sec. The ICCD is basically an integrating device. Its pixel resolution in not yet satisfactory for precision applications.
Instant snapshot of the internal structure of Unzen lava dome, Japan with airborne muography
Tanaka, Hiroyuki K. M.
2016-01-01
An emerging elementary particle imaging technique called muography has increasingly been used to resolve the internal structures of volcanoes with a spatial resolution of less than 100 m. However, land-based muography requires several days at least to acquire satisfactory image contrast and thus, it has not been a practical tool to diagnose the erupting volcano in a real time manner. To address this issue, airborne muography was implemented for the first time, targeting Heisei-Shinzan lava dome of Unzen volcano, Japan. Obtained in 2.5 hours, the resultant image clearly showed the density contrast inside the dome, which is essential information to predict the magnitude of the dome collapse. Since airborne muography is not restricted by topographic conditions for apparatus placements, we anticipate that the technique is applicable to creating images of this type of lava dome evolution from various angles in real time. PMID:28008978
NASA Technical Reports Server (NTRS)
Gilruth, R R; Turner, W N
1941-01-01
Report presents the results of an analysis made of the aileron control characteristics of numerous airplanes tested in flight by the National Advisory Committee for Aeronautics. By the use of previously developed theory, the observed values of pb/2v for the various wing-aileron arrangements were examined to determine the effective section characteristics of the various aileron types.
Bulk shielding facility quarterly report, October, November, and December 1976
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hurt, III, S. S.; Lance, E. D.; Thomas, J. R.
1977-08-01
The BSR operated at an average power level of 1,836 kw for 78.01 percent of the time during October, November, and December. Water-quality control in both the reactor primary and secondary cooling systems was satisfactory. The PCA was used in training programs and was operated on two occasions when the University of Kentucky students actively participated in training laboratories.
Digital radiography: optimization of image quality and dose using multi-frequency software.
Precht, H; Gerke, O; Rosendahl, K; Tingberg, A; Waaler, D
2012-09-01
New developments in processing of digital radiographs (DR), including multi-frequency processing (MFP), allow optimization of image quality and radiation dose. This is particularly promising in children as they are believed to be more sensitive to ionizing radiation than adults. To examine whether the use of MFP software reduces the radiation dose without compromising quality at DR of the femur in 5-year-old-equivalent anthropomorphic and technical phantoms. A total of 110 images of an anthropomorphic phantom were imaged on a DR system (Canon DR with CXDI-50 C detector and MLT[S] software) and analyzed by three pediatric radiologists using Visual Grading Analysis. In addition, 3,500 images taken of a technical contrast-detail phantom (CDRAD 2.0) provide an objective image-quality assessment. Optimal image-quality was maintained at a dose reduction of 61% with MLT(S) optimized images. Even for images of diagnostic quality, MLT(S) provided a dose reduction of 88% as compared to the reference image. Software impact on image quality was found significant for dose (mAs), dynamic range dark region and frequency band. By optimizing image processing parameters, a significant dose reduction is possible without significant loss of image quality.
Moore, C S; Wood, T J; Beavis, A W; Saunderson, J R
2013-07-01
The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson's correlation coefficient. Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, p<0.033) and eDE (R=0.77, p<0.008) were observed. Medical physics experts may use the physical image quality metrics described here in quality assurance programmes and optimisation studies with a degree of confidence that they reflect the clinical image quality in chest CR images acquired without an antiscatter grid. A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography.
Process perspective on image quality evaluation
NASA Astrophysics Data System (ADS)
Leisti, Tuomas; Halonen, Raisa; Kokkonen, Anna; Weckman, Hanna; Mettänen, Marja; Lensu, Lasse; Ritala, Risto; Oittinen, Pirkko; Nyman, Göte
2008-01-01
The psychological complexity of multivariate image quality evaluation makes it difficult to develop general image quality metrics. Quality evaluation includes several mental processes and ignoring these processes and the use of a few test images can lead to biased results. By using a qualitative/quantitative (Interpretation Based Quality, IBQ) methodology, we examined the process of pair-wise comparison in a setting, where the quality of the images printed by laser printer on different paper grades was evaluated. Test image consisted of a picture of a table covered with several objects. Three other images were also used, photographs of a woman, cityscape and countryside. In addition to the pair-wise comparisons, observers (N=10) were interviewed about the subjective quality attributes they used in making their quality decisions. An examination of the individual pair-wise comparisons revealed serious inconsistencies in observers' evaluations on the test image content, but not on other contexts. The qualitative analysis showed that this inconsistency was due to the observers' focus of attention. The lack of easily recognizable context in the test image may have contributed to this inconsistency. To obtain reliable knowledge of the effect of image context or attention on subjective image quality, a qualitative methodology is needed.
PET and NIR Optical Imaging Using Self-Illuminating 64Cu-Doped Chelator-Free Gold Nanoclusters
Hu, Hao; Huang, Peng; Weiss, Orit Jacobson; Yan, Xuefeng; Yue, Xuyi; Zhang, Molly Gu; Tang, Yuxia; Nie, Liming; Ma, Ying; Niu, Gang; Wu, Kaichun; Chen, Xiaoyuan
2014-01-01
Self-illuminating fluorescence imaging without autofluorescence background interference has recently aroused more research interests in molecular imaging. Currently, only a few self-illuminating probes were developed, based mainly on toxic quantum dots such as CdSe, CdTe. Herein, we report a novel design of nontoxic self-illuminating gold nanocluster (64Cu-doped AuNCs) for dual-modality positron emission tomography (PET) and near-infrared (NIR) fluorescence imaging based on Cerenkov resonance energy transfer (CRET). PET radionuclide 64Cu was introduced by a chelator-free doping method, which played dual roles as the energy donor and the PET imaging source. Meanwhile, AuNCs acted as the energy acceptor for NIR fluorescence imaging. 64Cu-doped AuNCs exhibited efficient CRET-NIR and PET imaging both in vitro and in vivo. In a U87MG glioblastoma xenograft model, 64Cu-doped AuNCs showed high tumor uptake (14.9%ID/g at 18 h) and produced satisfactory tumor self-illuminating NIR images in the absence of external excitation. This self-illuminating nanocluster with non-toxicity and good biocompatibility can be employed as a novel imaging contrast agent for biomedical applications, especially for molecular imaging. PMID:25224367
PET and NIR optical imaging using self-illuminating (64)Cu-doped chelator-free gold nanoclusters.
Hu, Hao; Huang, Peng; Weiss, Orit Jacobson; Yan, Xuefeng; Yue, Xuyi; Zhang, Molly Gu; Tang, Yuxia; Nie, Liming; Ma, Ying; Niu, Gang; Wu, Kaichun; Chen, Xiaoyuan
2014-12-01
Self-illuminating fluorescence imaging without autofluorescence background interference has recently aroused more research interests in molecular imaging. Currently, only a few self-illuminating probes were developed, based mainly on toxic quantum dots such as CdSe, CdTe. Herein, we report a novel design of nontoxic self-illuminating gold nanocluster ((64)Cu-doped AuNCs) for dual-modality positron emission tomography (PET) and near-infrared (NIR) fluorescence imaging based on Cerenkov resonance energy transfer (CRET). PET radionuclide (64)Cu was introduced by a chelator-free doping method, which played dual roles as the energy donor and the PET imaging source. Meanwhile, AuNCs acted as the energy acceptor for NIR fluorescence imaging. (64)Cu-doped AuNCs exhibited efficient CRET-NIR and PET imaging both in vitro and in vivo. In a U87MG glioblastoma xenograft model, (64)Cu-doped AuNCs showed high tumor uptake (14.9 %ID/g at 18 h) and produced satisfactory tumor self-illuminating NIR images in the absence of external excitation. This self-illuminating nanocluster with non-toxicity and good biocompatibility can be employed as a novel imaging contrast agent for biomedical applications, especially for molecular imaging. Published by Elsevier Ltd.
Drees, R; Forrest, L J; Chappell, R
2009-07-01
Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity.
Banzato, T; Cherubini, G B; Atzori, M; Zotti, A
2018-05-01
An established deep neural network (DNN) based on transfer learning and a newly designed DNN were tested to predict the grade of meningiomas from magnetic resonance (MR) images in dogs and to determine the accuracy of classification of using pre- and post-contrast T1-weighted (T1W), and T2-weighted (T2W) MR images. The images were randomly assigned to a training set, a validation set and a test set, comprising 60%, 10% and 30% of images, respectively. The combination of DNN and MR sequence displaying the highest discriminating accuracy was used to develop an image classifier to predict the grading of new cases. The algorithm based on transfer learning using the established DNN did not provide satisfactory results, whereas the newly designed DNN had high classification accuracy. On the basis of classification accuracy, an image classifier built on the newly designed DNN using post-contrast T1W images was developed. This image classifier correctly predicted the grading of 8 out of 10 images not included in the data set. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Ziessman, Harvey A; Majd, Massoud
2009-07-01
We reviewed our experience with (99m)technetium dimercapto-succinic acid scintigraphy obtained during an imaging pilot study for a multicenter investigation (Randomized Intervention for Children With Vesicoureteral Reflux) of the effectiveness of daily antimicrobial prophylaxis for preventing recurrent urinary tract infection and renal scarring. We analyzed imaging methodology and its relation to diagnostic image quality. (99m)Technetium dimercapto-succinic acid imaging guidelines were provided to participating sites. High-resolution planar imaging with parallel hole or pinhole collimation was required. Two core reviewers evaluated all submitted images. Analysis included appropriate views, presence or lack of patient motion, adequate magnification, sufficient counts and diagnostic image quality. Inter-reader agreement was evaluated. We evaluated 70, (99m)technetium dimercapto-succinic acid studies from 14 institutions. Variability was noted in methodology and image quality. Correlation (r value) between dose administered and patient age was 0.780. For parallel hole collimator imaging good correlation was noted between activity administered and counts (r = 0.800). For pinhole imaging the correlation was poor (r = 0.110). A total of 10 studies (17%) were rejected for quality issues of motion, kidney overlap, inadequate magnification, inadequate counts and poor quality images. The submitting institution was informed and provided with recommendations for improving quality, and resubmission of another study was required. Only 4 studies (6%) were judged differently by the 2 reviewers, and the differences were minor. Methodology and image quality for (99m)technetium dimercapto-succinic acid scintigraphy varied more than expected between institutions. The most common reason for poor image quality was inadequate count acquisition with insufficient attention to the tradeoff between administered dose, length of image acquisition, start time of imaging and resulting image quality. Inter-observer core reader agreement was high. The pilot study ensured good diagnostic quality standardized images for the Randomized Intervention for Children With Vesicoureteral Reflux investigation.
NASA Astrophysics Data System (ADS)
Wu, Z.; Luo, Z.; Zhang, Y.; Guo, F.; He, L.
2018-04-01
A Modulation Transfer Function (MTF)-based fuzzy comprehensive evaluation method was proposed in this paper for the purpose of evaluating high-resolution satellite image quality. To establish the factor set, two MTF features and seven radiant features were extracted from the knife-edge region of image patch, which included Nyquist, MTF0.5, entropy, peak signal to noise ratio (PSNR), average difference, edge intensity, average gradient, contrast and ground spatial distance (GSD). After analyzing the statistical distribution of above features, a fuzzy evaluation threshold table and fuzzy evaluation membership functions was established. The experiments for comprehensive quality assessment of different natural and artificial objects was done with GF2 image patches. The results showed that the calibration field image has the highest quality scores. The water image has closest image quality to the calibration field, quality of building image is a little poor than water image, but much higher than farmland image. In order to test the influence of different features on quality evaluation, the experiment with different weights were tested on GF2 and SPOT7 images. The results showed that different weights correspond different evaluating effectiveness. In the case of setting up the weights of edge features and GSD, the image quality of GF2 is better than SPOT7. However, when setting MTF and PSNR as main factor, the image quality of SPOT7 is better than GF2.
McCord, Layne K; Scarfe, William C; Naylor, Rachel H; Scheetz, James P; Silveira, Anibal; Gillespie, Kevin R
2007-05-01
The objectives of this study were to compare the effect of JPEG 2000 compression of hand-wrist radiographs on observer image quality qualitative assessment and to compare with a software-derived quantitative image quality index. Fifteen hand-wrist radiographs were digitized and saved as TIFF and JPEG 2000 images at 4 levels of compression (20:1, 40:1, 60:1, and 80:1). The images, including rereads, were viewed by 13 orthodontic residents who determined the image quality rating on a scale of 1 to 5. A quantitative analysis was also performed by using a readily available software based on the human visual system (Image Quality Measure Computer Program, version 6.2, Mitre, Bedford, Mass). ANOVA was used to determine the optimal compression level (P < or =.05). When we compared subjective indexes, JPEG compression greater than 60:1 significantly reduced image quality. When we used quantitative indexes, the JPEG 2000 images had lower quality at all compression ratios compared with the original TIFF images. There was excellent correlation (R2 >0.92) between qualitative and quantitative indexes. Image Quality Measure indexes are more sensitive than subjective image quality assessments in quantifying image degradation with compression. There is potential for this software-based quantitative method in determining the optimal compression ratio for any image without the use of subjective raters.
Image quality scaling of electrophotographic prints
NASA Astrophysics Data System (ADS)
Johnson, Garrett M.; Patil, Rohit A.; Montag, Ethan D.; Fairchild, Mark D.
2003-12-01
Two psychophysical experiments were performed scaling overall image quality of black-and-white electrophotographic (EP) images. Six different printers were used to generate the images. There were six different scenes included in the experiment, representing photographs, business graphics, and test-targets. The two experiments were split into a paired-comparison experiment examining overall image quality, and a triad experiment judging overall similarity and dissimilarity of the printed images. The paired-comparison experiment was analyzed using Thurstone's Law, to generate an interval scale of quality, and with dual scaling, to determine the independent dimensions used for categorical scaling. The triad experiment was analyzed using multidimensional scaling to generate a psychological stimulus space. The psychophysical results indicated that the image quality was judged mainly along one dimension and that the relationships among the images can be described with a single dimension in most cases. Regression of various physical measurements of the images to the paired comparison results showed that a small number of physical attributes of the images could be correlated with the psychophysical scale of image quality. However, global image difference metrics did not correlate well with image quality.
Hsu, L-F; Hung, C-L; Kuo, L-J; Tsai, P-S
2017-09-01
No instrument is available to assess the impact of faecal incontinence (FI) of quality of life for Chinese-speaking population. The purpose of the study was to adapt the Faecal Incontinence Quality of Life Scale (FIQL) for patients with colorectal cancer, assess the factor structure and reduce the items for brevity. A sample of 120 participants were enrolled. Internal consistency, test-retest reliability, and convergent and contrasted-groups validity were assessed. Construct validity was analysed using an exploratory and confirmatory factor analyses (CFA). The internal consistency (Cronbach's α of the total scale and four subscales = 0.98 and 0.97, 0.96, 0.92, 0.82 respectively), test-retest reliability (intraclass correlation coefficients ≥.98 for all scales with p < .001) and significant correlations of all scales with selected subscales of the Medical Outcomes Study 36-Item Short-Form Health Survey and the Wexner scale suggested satisfactory reliability and validity. The severe FI group (with a Wexner score ≥9) scored significantly lower on the scale than the less severe FI group (with a Wexner score <9) did (p < .001). The CFA supported a two-factor structure and demonstrated an excellent model fit of the 15-item abbreviated version of the FIQL-Chinese. The FIQL-Chinese has satisfactory validity and reliability and the abbreviated version may be more practical and applicable. © 2016 John Wiley & Sons Ltd.
Combined Effects of Chewing Ability and Dietary Diversity on Medical Service Use and Expenditures.
Lo, Yuan-Ting C; Wahlqvist, Mark L; Chang, Yu-Hung; Lee, Meei-Shyuan
2016-06-01
To examine whether chewing ability affects healthcare use and expenditure and whether improving dietary quality alleviates any such effects. Prospective cohort. The Elderly Nutrition and Health Survey in Taiwan (1999-2000), a nationwide community-based survey of people aged 65 and older. Individuals aged 65 and older (N = 1,793; 903 men, 890 women). Chewing ability (satisfactory or unsatisfactory) was assessed using a questionnaire, and dietary quality was assessed using a 24-hour dietary recall as a dietary diversity score. Data on annual medical use and expenditures from the interview date until December 31, 2006, were collected from National Health Insurance claims. Generalized linear models were used to assess the associations between chewing ability, dietary quality, and annual medical usage or expenditure. After 8 years of follow-up, older adults with unsatisfactory chewing ability had considerably higher emergency, hospitalization, and total medical expenditures. Older adults with unsatisfactory chewing ability and a poor diet used fewer annual preventive care and dental services than those with satisfactory chewing ability but had longer hospital stays and higher expenditures. After adjusting for covariates, unsatisfactory chewing ability resulted in significantly longer hospital stays in participants with a poor diet (β = 2.34, 95% confidence interval = 2.02-2.71, P < .001). Unsatisfactory chewing ability and a less-diverse diet together are associated with longer hospital stays and higher medical expenditures. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.
Mirzamani, Neda; Chau, Karen; Rafael, Oana; Shergill, Uday; Sajjan, Sujata; Sumskaya, Irina; Gimenez, Cecilia; Klein, Melissa; Das, Kasturi
2017-10-01
The quality of cervicovaginal smears determines the success of cytology in screening programs for cervical cancer. Bethesda 2014 revisited the adequacy criteria for atrophic smears and redefined the squamous cell count in the "unsatisfactory" category. In this study, we evaluated the smear quality of Thinprep liquid-based cervicovaginal Papanicolaou cytology slides (TPS) that were previously deemed unsatisfactory, to determine reasons for such categorization. In addition, we attempted to establish the impact of the new adequacy criteria on the rate and management of unsatisfactory diagnosis. About 234 unsatisfactory TPS were examined. The reasons for unsatisfactory were noted. The number of squamous cells was recounted, as per the new Bethesda criteria, in borderline adequacy cases that showed an atrophic pattern. The leading cause for unsatisfactory TPS was lubricating gel, followed by blood, as observed in older and younger age groups, respectively (Figure 1). Eleven borderline cases were reclassified as "satisfactory" using the new Bethesda cell count, with 27% above 60 years of age. About 82% of these borderline cases were negative for intraepithelial lesion or malignancy on repeat testing. There was no difference of management or change in rate of unsatisfactory when patients above 60 were reclassified into the satisfactory category using the new Bethesda count. However, a larger study is needed to evaluate whether the new recommendation for minimum cellularity can be implemented in patients above a certain age cut-off. The study highlights the need for improvement in collection practices and education of practitioners. © 2017 Wiley Periodicals, Inc.
Du, Yi-fei; Zhou, Wei-na; Li, Jie; Jiang, Hong-bing; Yuan, Hua; Wan, Lin-zhong
2014-11-01
The aim of this study was to investigate the reliability and outcomes of a new design of facial artery perforator flaps, extending from the angle of the mouth to the border of the mandible, for the reconstruction of small- to medium-sized intraoral defects. The technique had been used in 23 patients between February 2009 and August 2012. The locations of intraoral defects included the tongue, the floor of the mouth, the inferior gingival mucosa, and the sublingual gland. All flaps were monitored for complications including skin loss and ischemia. The functions of appearance, swallowing, and speech were assessed 6 months after operation with the University of Washington Quality of Life Questionnaire. All flaps presented with satisfactory results except for one, which demonstrated superficial tip necrosis that settled after conservative treatment. The follow-up period ranged from 6 to 12 months, and 1 patient died as a result of pulmonary metastasis, and 3 patients underwent second surgery because of local tumor recurrence (2patients) and cervical recurrence (1 patient). Nineteen patients were assessed with the University of Washington Quality of Life Questionnaire, and the mean (SD) scores of appearance, swallowing, and speech were 57.89 (14.45), 83.68 (19.98), and 81.58 (23.16), respectively. This design of facial artery perforator flaps could provide an efficient and cost-effective method for reconstruction of small- to medium-sized intraoral defects with a low surgical morbidity and satisfactory levels of quality of life.
Fang, Cheng; Wang, Kun; Zeng, Chaoting; Chi, Chongwei; Shang, Wenting; Ye, Jinzuo; Mao, Yamin; Fan, Yingfang; Yang, Jian; Xiang, Nan; Zeng, Ning; Zhu, Wen; Fang, Chihua; Tian, Jie
2016-01-01
Tissue necrosis commonly accompanies the development of a wide range of serious diseases. Therefore, highly sensitive detection and precise boundary delineation of necrotic tissue via effective imaging techniques are crucial for clinical treatments; however, no imaging modalities have achieved satisfactory results to date. Although fluorescence molecular imaging (FMI) shows potential in this regard, no effective necrosis-avid fluorescent probe has been developed for clinical applications. Here, we demonstrate that indocyanine green (ICG) can achieve high avidity of necrotic tissue owing to its interaction with lipoprotein (LP) and phospholipids. The mechanism was explored at the cellular and molecular levels through a series of in vitro studies. Detection of necrotic tissue and real-time image-guided surgery were successfully achieved in different organs of different animal models with the help of FMI using in house-designed imaging devices. The results indicated that necrotic tissue with a 0.6 mm diameter could be effectively detected with precise boundary definition. We believe that the new discovery and the associated imaging techniques will improve personalized and precise surgery in the near future. PMID:26864116
Benchmarking performance: Environmental impact statements in Egypt
DOE Office of Scientific and Technical Information (OSTI.GOV)
Badr, El-Sayed A., E-mail: ebadr@mans.edu.e; Zahran, Ashraf A., E-mail: ashraf_zahran@yahoo.co; Cashmore, Matthew, E-mail: m.cashmore@uea.ac.u
Environmental impact assessment (EIA) was formally introduced in Egypt in 1994. This short paper evaluates 'how well' the EIA process is working in practice in Egypt, by reviewing the quality of 45 environmental impact statements (EISs) produced between 2000 and 2007 for a variety of project types. The Lee and Colley review package was used to assess the quality of the selected EISs. About 69% of the EISs sampled were found to be of a satisfactory quality. An assessment of the performance of different elements of the EIA process indicates that descriptive tasks tend to be performed better than scientificmore » tasks. The quality of core elements of EIA (e.g., impact prediction, significance evaluation, scoping and consideration of alternatives) appears to be particularly problematic. Variables that influence the quality of EISs are identified and a number of broad recommendations are made for improving the effectiveness of the EIA system.« less
Automated daily quality control analysis for mammography in a multi-unit imaging center.
Sundell, Veli-Matti; Mäkelä, Teemu; Meaney, Alexander; Kaasalainen, Touko; Savolainen, Sauli
2018-01-01
Background The high requirements for mammography image quality necessitate a systematic quality assurance process. Digital imaging allows automation of the image quality analysis, which can potentially improve repeatability and objectivity compared to a visual evaluation made by the users. Purpose To develop an automatic image quality analysis software for daily mammography quality control in a multi-unit imaging center. Material and Methods An automated image quality analysis software using the discrete wavelet transform and multiresolution analysis was developed for the American College of Radiology accreditation phantom. The software was validated by analyzing 60 randomly selected phantom images from six mammography systems and 20 phantom images with different dose levels from one mammography system. The results were compared to a visual analysis made by four reviewers. Additionally, long-term image quality trends of a full-field digital mammography system and a computed radiography mammography system were investigated. Results The automated software produced feature detection levels comparable to visual analysis. The agreement was good in the case of fibers, while the software detected somewhat more microcalcifications and characteristic masses. Long-term follow-up via a quality assurance web portal demonstrated the feasibility of using the software for monitoring the performance of mammography systems in a multi-unit imaging center. Conclusion Automated image quality analysis enables monitoring the performance of digital mammography systems in an efficient, centralized manner.
Assessing product image quality for online shopping
NASA Astrophysics Data System (ADS)
Goswami, Anjan; Chung, Sung H.; Chittar, Naren; Islam, Atiq
2012-01-01
Assessing product-image quality is important in the context of online shopping. A high quality image that conveys more information about a product can boost the buyer's confidence and can get more attention. However, the notion of image quality for product-images is not the same as that in other domains. The perception of quality of product-images depends not only on various photographic quality features but also on various high level features such as clarity of the foreground or goodness of the background etc. In this paper, we define a notion of product-image quality based on various such features. We conduct a crowd-sourced experiment to collect user judgments on thousands of eBay's images. We formulate a multi-class classification problem for modeling image quality by classifying images into good, fair and poor quality based on the guided perceptual notions from the judges. We also conduct experiments with regression using average crowd-sourced human judgments as target. We compute a pseudo-regression score with expected average of predicted classes and also compute a score from the regression technique. We design many experiments with various sampling and voting schemes with crowd-sourced data and construct various experimental image quality models. Most of our models have reasonable accuracies (greater or equal to 70%) on test data set. We observe that our computed image quality score has a high (0.66) rank correlation with average votes from the crowd sourced human judgments.
[QUIPS: quality improvement in postoperative pain management].
Meissner, Winfried
2011-01-01
Despite the availability of high-quality guidelines and advanced pain management techniques acute postoperative pain management is still far from being satisfactory. The QUIPS (Quality Improvement in Postoperative Pain Management) project aims to improve treatment quality by means of standardised data acquisition, analysis of quality and process indicators, and feedback and benchmarking. During a pilot phase funded by the German Ministry of Health (BMG), a total of 12,389 data sets were collected from six participating hospitals. Outcome improved in four of the six hospitals. Process indicators, such as routine pain documentation, were only poorly correlated with outcomes. To date, more than 130 German hospitals use QUIPS as a routine quality management tool. An EC-funded parallel project disseminates the concept internationally. QUIPS demonstrates that patient-reported outcomes in postoperative pain management can be benchmarked in routine clinical practice. Quality improvement initiatives should use outcome instead of structural and process parameters. The concept is transferable to other fields of medicine. Copyright © 2011. Published by Elsevier GmbH.
Comparative Analysis of Reconstructed Image Quality in a Simulated Chromotomographic Imager
2014-03-01
quality . This example uses five basic images a backlit bar chart with random intensity, 100 nm separation. A total of 54 initial target...compared for a variety of scenes. Reconstructed image quality is highly dependent on the initial target hypercube so a total of 54 initial target...COMPARATIVE ANALYSIS OF RECONSTRUCTED IMAGE QUALITY IN A SIMULATED CHROMOTOMOGRAPHIC IMAGER THESIS
A formal approach for the prediction of the critical heat flux in subcooled water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lombardi, C.
1995-09-01
The critical heat flux (CHF) in subcooled water at high mass fluxes are not yet satisfactory correlated. For this scope a formal approach is here followed, which is based on an extension of the parameters and the correlation used for the dryout prediction for medium high quality mixtures. The obtained correlation, in spite of its simplicity and its explicit form, yields satisfactory predictions, also when applied to more conventional CHF data at low-medium mass fluxes and high pressures. Further improvements are possible, if a more complete data bank will be available. The main and general open item is the definitionmore » of a criterion, depending only on independent parameters, such as mass flux, pressure, inlet subcooling and geometry, to predict whether the heat transfer crisis will result as a DNB or a dryout phenomenon.« less
NASA Technical Reports Server (NTRS)
Polhamus, Edward C.; King, Thomas J., Jr.
1949-01-01
An investigation was made in the Langley high-speed 7- by 10-foot tunnel to determine the high-speed lateral and directional stability characteristics of a 0.10-scale model of the Grumman XF9F-2 airplane in the Mach number range from 0.40 to 0.85. The results indicate that static lateral and directional stability is present throughout the Mach number range investigated although in the Mach number range from 0.75 to 0.85 there is an appreciable decrease in rolling moment due to sideslip. Calculations of the dynamic stability indicate that according to current flying-quality requirements the damping of the lateral oscillation, although probably satisfactory for the sea-level condition, may not be satisfactory for the majority of the altitude conditions investigated
Retinal Image Quality Assessment for Spaceflight-Induced Vision Impairment Study
NASA Technical Reports Server (NTRS)
Vu, Amanda Cadao; Raghunandan, Sneha; Vyas, Ruchi; Radhakrishnan, Krishnan; Taibbi, Giovanni; Vizzeri, Gianmarco; Grant, Maria; Chalam, Kakarla; Parsons-Wingerter, Patricia
2015-01-01
Long-term exposure to space microgravity poses significant risks for visual impairment. Evidence suggests such vision changes are linked to cephalad fluid shifts, prompting a need to directly quantify microgravity-induced retinal vascular changes. The quality of retinal images used for such vascular remodeling analysis, however, is dependent on imaging methodology. For our exploratory study, we hypothesized that retinal images captured using fluorescein imaging methodologies would be of higher quality in comparison to images captured without fluorescein. A semi-automated image quality assessment was developed using Vessel Generation Analysis (VESGEN) software and MATLAB® image analysis toolboxes. An analysis of ten images found that the fluorescein imaging modality provided a 36% increase in overall image quality (two-tailed p=0.089) in comparison to nonfluorescein imaging techniques.
Joshi, Anuja; Gislason-Lee, Amber J; Keeble, Claire; Sivananthan, Uduvil M
2017-01-01
Objective: The aim of this research was to quantify the reduction in radiation dose facilitated by image processing alone for percutaneous coronary intervention (PCI) patient angiograms, without reducing the perceived image quality required to confidently make a diagnosis. Methods: Incremental amounts of image noise were added to five PCI angiograms, simulating the angiogram as having been acquired at corresponding lower dose levels (10–89% dose reduction). 16 observers with relevant experience scored the image quality of these angiograms in 3 states—with no image processing and with 2 different modern image processing algorithms applied. These algorithms are used on state-of-the-art and previous generation cardiac interventional X-ray systems. Ordinal regression allowing for random effects and the delta method were used to quantify the dose reduction possible by the processing algorithms, for equivalent image quality scores. Results: Observers rated the quality of the images processed with the state-of-the-art and previous generation image processing with a 24.9% and 15.6% dose reduction, respectively, as equivalent in quality to the unenhanced images. The dose reduction facilitated by the state-of-the-art image processing relative to previous generation processing was 10.3%. Conclusion: Results demonstrate that statistically significant dose reduction can be facilitated with no loss in perceived image quality using modern image enhancement; the most recent processing algorithm was more effective in preserving image quality at lower doses. Advances in knowledge: Image enhancement was shown to maintain perceived image quality in coronary angiography at a reduced level of radiation dose using computer software to produce synthetic images from real angiograms simulating a reduction in dose. PMID:28124572
Studies of the Lateral-Directional Flying Qualities of a Tandem Helicopter in Forward Flight
NASA Technical Reports Server (NTRS)
Amer, Kenneth B; Tapscott, Robert J
1954-01-01
An investigation of the lateral-directional flying qualities of a tandem-rotor helicopter in forward flight was undertaken to determine desirable goals for helicopter lateral-directional flying qualities and possible methods of achieving these goals in the tandem-rotor helicopter. Comparison between directional stability as measured in flight and rotor-off model tests in a wind tunnel shows qualitative agreement and, hence, indicates such wind-tunnel test, despite the absence of the rotors, to be one effective method of studying means of improving the directional stability of the tandem helicopter. Flight-test measurements of turns and oscillations, in conjunction with analytical studies, suggest possible practical methods of achieving the goals of satisfactory turn and oscillatory characteristics in the tandem helicopter.
NASA Technical Reports Server (NTRS)
Mcneill, Walter, E.; Chung, William W.; Stortz, Michael W.
1995-01-01
A piloted motion simulator evaluation, using the NASA Ames Vertical Motion Simulator, was conducted in support of a NASA Lewis Contractual study of the integration of flight and propulsion systems of a STOVL aircraft. Objectives of the study were to validate the Design Methods for Integrated Control Systems (DMICS) concept, to evaluate the handling qualities, and to assess control power usage. The E-7D ejector-augmentor STOVL fighter design served as the basis for the simulation. Handling-qualities ratings were obtained during precision hover and shipboard landing tasks. Handling-qualities ratings for these tasks ranged from satisfactory to adequate. Further improvement of the design process to fully validate the DMICS concept appears to be warranted.
Neuropathic pain screening questionnaires have limited measurement properties. A systematic review.
Mathieson, Stephanie; Maher, Christopher G; Terwee, Caroline B; Folly de Campos, Tarcisio; Lin, Chung-Wei Christine
2015-08-01
The Douleur Neuropathique 4 (DN4), ID Pain, Leeds Assessment of Neuropathic Symptoms and Signs (LANSS), PainDETECT, and Neuropathic Pain Questionnaire have been recommended as screening questionnaires for neuropathic pain. This systematic review aimed to evaluate the measurement properties (eg, criterion validity and reliability) of these questionnaires. Online database searches were conducted and two independent reviewers screened studies and extracted data. Methodological quality of included studies and the measurement properties were assessed against established criteria. A modified Grading of Recommendations Assessment, Development and Evaluation approach was used to summarize the level of evidence. Thirty-seven studies were included. Most studies recruited participants from pain clinics. The original version of the DN4 (French) and Neuropathic Pain Questionnaire (English) had the most number of satisfactory measurement properties. The ID Pain (English) demonstrated satisfactory hypothesis testing and reliability, but all other properties tested were unsatisfactory. The LANSS (English) was unsatisfactory for all properties, except specificity. The PainDETECT (English) demonstrated satisfactory hypothesis testing and criterion validity. In general, the cross-cultural adaptations had less evidence than the original versions. Overall, the DN4 and Neuropathic Pain Questionnaire were most suitable for clinical use. These screening questionnaires should not replace a thorough clinical assessment. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
Ritter, Lutz; Mischkowski, Robert A; Neugebauer, Jörg; Dreiseidler, Timo; Scheer, Martin; Keeve, Erwin; Zöller, Joachim E
2009-09-01
The aim was to determine the influence of patient age, gender, body mass index (BMI), amount of dental restorations, and implants on image quality of cone-beam computerized tomography (CBCT). Fifty CBCT scans of a preretail version of Galileos (Sirona, Germany) were investigated retrospectively by 4 observers regarding image quality of 6 anatomic structures, pathologic findings detection, subjective exposure quality, and artifacts. Patient age, BMI, gender, amount of dental restorations, and implants were recorded and statistically tested for correlations to image quality. A negative effect on image quality was found statistically significantly correlated with age and the amount of dental restorations. None of the investigated image features were garbled by any of the investigated influence factors. Age and the amount of dental restorations appear to have a negative impact on CBCT image quality, whereas gender and BMI do not. Image quality of mental foramen, mandibular canal, and nasal floor are affected negatively by age but not by the amount of dental restorations. Further studies are required to elucidate influence factors on CBCT image quality.
Wood, T J; Beavis, A W; Saunderson, J R
2013-01-01
Objective: The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. Methods: The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson’s correlation coefficient. Results: Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, p<0.033) and eDE (R=0.77, p<0.008) were observed. Conclusion: Medical physics experts may use the physical image quality metrics described here in quality assurance programmes and optimisation studies with a degree of confidence that they reflect the clinical image quality in chest CR images acquired without an antiscatter grid. Advances in knowledge: A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography. PMID:23568362
Kim, Chulhong; Zemp, Roger J; Wang, Lihong V
2006-08-15
Biophotonic imaging with ultrasound-modulated optical tomography (UOT) promises ultrasonically resolved imaging in biological tissues. A key challenge in this imaging technique is a low signal-to-noise ratio (SNR). We show significant UOT signal enhancement by using intense time-gated acoustic bursts. A CCD camera captured the speckle pattern from a laser-illuminated tissue phantom. Differences in speckle contrast were observed when ultrasonic bursts were applied, compared with when no ultrasound was applied. When CCD triggering was synchronized with burst initiation, acoustic-radiation-force-induced displacements were detected. To avoid mechanical contrast in UOT images, the CCD camera acquisition was delayed several milliseconds until transient effects of acoustic radiation force attenuated to a satisfactory level. The SNR of our system was sufficiently high to provide an image pixel per acoustic burst without signal averaging. Because of the substantially improved SNR, the use of intense acoustic bursts is a promising signal enhancement strategy for UOT.
Gaussian mixture models-based ship target recognition algorithm in remote sensing infrared images
NASA Astrophysics Data System (ADS)
Yao, Shoukui; Qin, Xiaojuan
2018-02-01
Since the resolution of remote sensing infrared images is low, the features of ship targets become unstable. The issue of how to recognize ships with fuzzy features is an open problem. In this paper, we propose a novel ship target recognition algorithm based on Gaussian mixture models (GMMs). In the proposed algorithm, there are mainly two steps. At the first step, the Hu moments of these ship target images are calculated, and the GMMs are trained on the moment features of ships. At the second step, the moment feature of each ship image is assigned to the trained GMMs for recognition. Because of the scale, rotation, translation invariance property of Hu moments and the power feature-space description ability of GMMs, the GMMs-based ship target recognition algorithm can recognize ship reliably. Experimental results of a large simulating image set show that our approach is effective in distinguishing different ship types, and obtains a satisfactory ship recognition performance.
Kamauu, Aaron W C; DuVall, Scott L; Robison, Reid J; Liimatta, Andrew P; Wiggins, Richard H; Avrin, David E
2006-01-01
Although digital teaching files are important to radiology education, there are no current satisfactory solutions for export of Digital Imaging and Communications in Medicine (DICOM) images from picture archiving and communication systems (PACS) in desktop publishing format. A vendor-neutral digital teaching file, the Radiology Interesting Case Server (RadICS), offers an efficient tool for harvesting interesting cases from PACS without requiring modifications of the PACS configurations. Radiologists push imaging studies from PACS to RadICS via the standard DICOM Send process, and the RadICS server automatically converts the DICOM images into the Joint Photographic Experts Group format, a common desktop publishing format. They can then select key images and create an interesting case series at the PACS workstation. RadICS was tested successfully against multiple unmodified commercial PACS. Using RadICS, radiologists are able to harvest and author interesting cases at the point of clinical interpretation with minimal disruption in clinical work flow. RSNA, 2006
Optimizing the optical wavelength for the photoacoustic imaging of inflammatory arthritis
NASA Astrophysics Data System (ADS)
Jo, Janggun; Xu, Guan; Hu, Jack; Francis, Sheeja; Marquardt, April; Yuan, Jie; Girish, Gandikota; Wang, Xueding
2015-03-01
With the capability of assessing high resolution optical information in soft tissues at imaging depth up to several centimeters, innovative biomedical photoacoustic imaging (PAI) offers benefits to diagnosis and treatment monitoring of inflammatory arthritis, particularly in combination with more established ultrasonography (US). In this work, a PAI and US dual-modality system facilitating both imaging functions in a real-time fashion was developed and initially tested for its clinical performance on patients with active inflammatory arthritis. Photoacoustic (PA) images of metacarpophalangeal (MCP) joints were acquired at 580-nm wavelength that provides a desired balance between optical absorption of blood and attenuation in background tissue. The results from six patients and six normal volunteers used as a control demonstrated the satisfactory sensitivity of PAI in assessing the physiological changes in the joints, specifically enhanced blood flow as a result of active synovitis. This preliminary study suggests that PAI, by revealing vascular features suggestive of joint inflammation, could be a valuable supplement to musculoskeletal US for rheumatology clinic.
Correction of data truncation artifacts in differential phase contrast (DPC) tomosynthesis imaging
NASA Astrophysics Data System (ADS)
Garrett, John; Ge, Yongshuai; Li, Ke; Chen, Guang-Hong
2015-10-01
The use of grating based Talbot-Lau interferometry permits the acquisition of differential phase contrast (DPC) imaging with a conventional medical x-ray source and detector. However, due to the limited area of the gratings, limited area of the detector, or both, data truncation image artifacts are often observed in tomographic DPC acquisitions and reconstructions, such as tomosynthesis (limited-angle tomography). When data are truncated in the conventional x-ray absorption tomosynthesis imaging, a variety of methods have been developed to mitigate the truncation artifacts. However, the same strategies used to mitigate absorption truncation artifacts do not yield satisfactory reconstruction results in DPC tomosynthesis reconstruction. In this work, several new methods have been proposed to mitigate data truncation artifacts in a DPC tomosynthesis system. The proposed methods have been validated using experimental data of a mammography accreditation phantom, a bovine udder, as well as several human cadaver breast specimens using a bench-top DPC imaging system at our facility.
A normal incidence X-ray telescope
NASA Technical Reports Server (NTRS)
Golub, Leon
1987-01-01
The postflight performance evaluation of the X-ray telescope was summarized. All payload systems and subsystems performed well within acceptable limits, with the sole exception of the light-blocking prefilters. Launch, flight and recovery were performed in a fully satisfactory manner. The payload was recovered in a timely manner and in excellent condition. The prefilter performance analysis showed that no X-ray images were detected on the processed flight film. Recommendations for improved performance are listed.
Desalu, Olufemi Olumuyiwa; Adeoti, Adekunle Olatayo; Ogunmola, Olarinde Jeffrey; Fadare, Joseph Olusesan; Kolawole, Tolutope Fasanmi
2016-01-01
To audit the quality of acute asthma care in two tertiary hospitals in a state in the southwestern region of Nigeria and to compare the clinical practice against the recommendations of the Global Initiative for Asthma (GINA) guideline. We carried out a retrospective analysis of 101 patients who presented with acute exacerbation of asthma to the hospital between November 2010 and October 2015. Majority of the cases were females (66.3%), <45 years of age (60.4%), and admitted in the wet season (64.4%). The median duration of hospital stay was 2 days (interquartile range; 1-3 days) and the mortality was 1.0%. At admission, 73 (72.3%) patients had their triggering factors documented and 33 (32.7%) had their severity assessed. Smoking status, medication adherence, serial oxygen saturation, and peak expiratory flow rate measurement were documented in less than half of the cases, respectively. Seventy-six (75.2%) patients had nebulized salbutamol, 89 (88.1%) had systemic corticosteroid, and 78 (77.2%) had within 1 h. On discharge, 68 (67.3%) patients were given follow-up appointment and 32 (31.7%) were reviewed within 30 days after discharge. Less than half were prescribed an inhaled corticosteroid (ICS), a self-management plan, or had their inhaler technique reviewed or controller medications adjusted. Overall, adherence to the GINA guideline was not satisfactory and was very poor among the medical officers. The quality of acute asthma care in our setting is not satisfactory, and there is a low level of compliance with most recommendations of asthma guidelines. This audit has implicated the need to address the non-performing areas and organizational issues to improve the quality of care.
Willis, Caroline; McLauchlin, Jim; Amar, Corinne; Sadler-Reeves, Lorraine; Elviss, Nicola; Aird, Heather; Fox, Andrew; Kaye, Moira
2016-04-01
Fresh fruit has been associated with a number of foodborne outbreaks in recent years. In particular, a large outbreak of listeriosis in the United States in 2011 was associated with consumption of cantaloupe melon, and an outbreak of Salmonella Newport in the United Kingdom and Europe (also in 2011) was linked to watermelon consumption. A study of precut fruit products from catering and retail premises in the United Kingdom was, therefore, carried out to assess their microbiological safety. Between January and March 2012, samples (1,188) of ready-to-eat precut fruit were collected from retail and catering premises in the United Kingdom, and 99% were of satisfactory microbiological quality. However, four samples (0.3%) were of an unsatisfactory quality (one with 800 CFU/g Listeria monocytogenes and three with >100 CFU/g Escherichia coli), and five samples (0.4%) were of a borderline quality owing to the presence of E. coli (two samples with a level of 20 CFU/g), Staphylococcus aureus (two samples with levels of >50 CFU/g), or L. monocytogenes (one sample with a level of 80 CFU/g). L. monocytogenes or other Listeria species were detected in a further 54 samples (4.5%) at levels below the threshold considered to be borderline or unsatisfactory. A significantly larger proportion of samples from one national supermarket chain was contaminated with L. monocytogenes than other supermarkets, and two types were, in this study, unique to this supermarket. This study shows that overall, the microbiological quality of ready-to-eat precut fruit was good. However, the presence of Listeria species in 5% of samples highlights the need for good hygiene during preparation and satisfactory temperature and time control during storage of these food products.
van Weert, Julia C M; Jansen, Jesse; de Bruijn, Gert-Jan; Noordman, Janneke; van Dulmen, Sandra; Bensing, Jozien M
2009-11-01
Knowing patients' needs is a prerequisite to ensure high quality cancer care. This study describes the development and psychometric properties of a patient-centred instrument to measure needs and actual experiences with communication preceding chemotherapy treatment: QUOTE(chemo). QUOTE-questionnaires (Quality Of care Through the patients' Eyes) are widely used to gain insight into unmet needs, but no validated, standardised questionnaire combining patients' needs and experiences surrounding chemotherapy treatment is available yet. To evaluate the psychometric properties of the QUOTE(chemo), content validity, internal structure and convergent validity were investigated amongst 345 cancer patients, new to chemotherapy, from 10 different hospitals. Literature study, focus group discussions and a categorisation procedure of 67 relevant topics revealed seven main themes: Treatment-related information, Prognosis information, Rehabilitation information, Coping information, Interpersonal communication, Tailored communication and Affective communication. Confirmatory factor analysis using structural equation modelling indicated that the measurement model provided good fit to the data with factor loadings ranging from .43 to .77. The seven QUOTE(chemo) dimensions captured relevant issues of concern with good internal consistency (alpha .72-.92), satisfactory item-total correlations (.35-.79) and satisfactory convergent validity. Affective communication, Treatment-related information and Rehabilitation information were perceived most important by patients. The instrument also appeared to be able to determine which aspects need improvement to ensure high quality care. The highest need for improvement was found for communicating Prognosis information and Rehabilitation information and for Interpersonal communication. These findings provide preliminary evidence of the reliability and validity of the QUOTE(chemo) for use in cancer care surrounding chemotherapy treatment. Researchers and health care providers can use the instrument to measure patients' needs and experiences with communication to identify aspects that need improvement.
On pictures and stuff: image quality and material appearance
NASA Astrophysics Data System (ADS)
Ferwerda, James A.
2014-02-01
Realistic images are a puzzle because they serve as visual representations of objects while also being objects themselves. When we look at an image we are able to perceive both the properties of the image and the properties of the objects represented by the image. Research on image quality has typically focused improving image properties (resolution, dynamic range, frame rate, etc.) while ignoring the issue of whether images are serving their role as visual representations. In this paper we describe a series of experiments that investigate how well images of different quality convey information about the properties of the objects they represent. In the experiments we focus on the effects that two image properties (contrast and sharpness) have on the ability of images to represent the gloss of depicted objects. We found that different experimental methods produced differing results. Specifically, when the stimulus images were presented using simultaneous pair comparison, observers were influenced by the surface properties of the images and conflated changes in image contrast and sharpness with changes in object gloss. On the other hand, when the stimulus images were presented sequentially, observers were able to disregard the image plane properties and more accurately match the gloss of the objects represented by the different quality images. These findings suggest that in understanding image quality it is useful to distinguish between quality of the imaging medium and the quality of the visual information represented by that medium.
Shaw, Leslee J; Blankstein, Ron; Jacobs, Jill E; Leipsic, Jonathon A; Kwong, Raymond Y; Taqueti, Viviany R; Beanlands, Rob S B; Mieres, Jennifer H; Flamm, Scott D; Gerber, Thomas C; Spertus, John; Di Carli, Marcelo F
2017-12-01
The aims of the current statement are to refine the definition of quality in cardiovascular imaging and to propose novel methodological approaches to inform the demonstration of quality in imaging in future clinical trials and registries. We propose defining quality in cardiovascular imaging using an analytical framework put forth by the Institute of Medicine whereby quality was defined as testing being safe, effective, patient-centered, timely, equitable, and efficient. The implications of each of these components of quality health care are as essential for cardiovascular imaging as they are for other areas within health care. Our proposed statement may serve as the foundation for integrating these quality indicators into establishing designations of quality laboratory practices and developing standards for value-based payment reform for imaging services. We also include recommendations for future clinical research to fulfill quality aims within cardiovascular imaging, including clinical hypotheses of improving patient outcomes, the importance of health status as an end point, and deferred testing options. Future research should evolve to define novel methods optimized for the role of cardiovascular imaging for detecting disease and guiding treatment and to demonstrate the role of cardiovascular imaging in facilitating healthcare quality. © 2017 American Heart Association, Inc.
Objective quality assessment for multiexposure multifocus image fusion.
Hassen, Rania; Wang, Zhou; Salama, Magdy M A
2015-09-01
There has been a growing interest in image fusion technologies, but how to objectively evaluate the quality of fused images has not been fully understood. Here, we propose a method for objective quality assessment of multiexposure multifocus image fusion based on the evaluation of three key factors of fused image quality: 1) contrast preservation; 2) sharpness; and 3) structure preservation. Subjective experiments are conducted to create an image fusion database, based on which, performance evaluation shows that the proposed fusion quality index correlates well with subjective scores, and gives a significant improvement over the existing fusion quality measures.
Photoacoustic imaging of inflammatory arthritis in human joints
NASA Astrophysics Data System (ADS)
Jo, Janggun; Xu, Guan; Marquardt, April; Francis, Sheeja; Yuan, Jie; Girish, Dhanuj; Girish, Gandikota; Wang, Xueding
2016-02-01
The ducal imaging with photoacoustic imaging (PAI) that is an emerging technology and clinical ultrasound imaging that is an established modality is developed for the imaging of early inflammatory arthritis. PAI is sensitive to blood volume, not limited by flow like ultrasound, holding great promise for the earliest detection of increase in blood volume and angiogenesis - a key early finding inflammation PAI has the capability of assessing inflammation in superficial human soft tissues, offering potential benefits in diagnosis, treatment and monitoring of inflammatory arthritis. PAI combined with ultrasonography (US), is a real time dual-modality system developed and tested to identify active synovitis in metacarpophalangeal (MCP) joints of 10 arthritis patients and 10 normal volunteers. Photoacoustic images of the joints were acquired at 580-nm laser wavelength, which provided the desired balance between the optical contrast of hemoglobin over bone cortex and the imaging depth. Confirmed by US Doppler imaging, the results from ten patients and ten normal volunteers demonstrated satisfactory sensitivity of PAI in assessing enhanced blood flow due to active synovitis. This preliminary study suggests that photoacoustic imaging, by identifying early increase in blood volume, related to increased vascularity, a hallmark of joint inflammation, could be a valuable supplement to musculoskeletal US.
Perceptual quality prediction on authentically distorted images using a bag of features approach
Ghadiyaram, Deepti; Bovik, Alan C.
2017-01-01
Current top-performing blind perceptual image quality prediction models are generally trained on legacy databases of human quality opinion scores on synthetically distorted images. Therefore, they learn image features that effectively predict human visual quality judgments of inauthentic and usually isolated (single) distortions. However, real-world images usually contain complex composite mixtures of multiple distortions. We study the perceptually relevant natural scene statistics of such authentically distorted images in different color spaces and transform domains. We propose a “bag of feature maps” approach that avoids assumptions about the type of distortion(s) contained in an image and instead focuses on capturing consistencies—or departures therefrom—of the statistics of real-world images. Using a large database of authentically distorted images, human opinions of them, and bags of features computed on them, we train a regressor to conduct image quality prediction. We demonstrate the competence of the features toward improving automatic perceptual quality prediction by testing a learned algorithm using them on a benchmark legacy database as well as on a newly introduced distortion-realistic resource called the LIVE In the Wild Image Quality Challenge Database. We extensively evaluate the perceptual quality prediction model and algorithm and show that it is able to achieve good-quality prediction power that is better than other leading models. PMID:28129417
After massive weight loss: patients' expectations of body contouring surgery.
Kitzinger, Hugo B; Abayev, Sara; Pittermann, Anna; Karle, Birgit; Bohdjalian, Arthur; Langer, Felix B; Prager, Gerhard; Frey, Manfred
2012-04-01
Massive weight loss following bariatric surgery leads to excess skin with functional and aesthetic impairments. Surplus skin can then contribute to problems with additional weight loss or gain. The aims of the current study were to evaluate the frequency of massive soft tissue development in gastric bypass patients, to determine whether males and females experience similar post-bypass body changes, and to learn about the expectations and impairments related to body contouring surgery. A questionnaire addressing information on the satisfaction of body image, quality of life, and expectation of body contouring surgery following massive weight loss was mailed to 425 patients who had undergone gastric bypass surgery between 2003 and 2009. Of these 425 individuals, 252 (59%) patients completed the survey. Ninety percent of women and 88% of men surveyed rated their appearance following massive weight loss as satisfactory, good, or very good. However, 96% of all patients developed surplus skin, which caused intertriginous dermatitis and itching. In addition, patients reported problems with physical activity (playing sports) and finding clothing that fit appropriately. Moreover, 75% of female and 68% of male patients reported desiring body contouring surgery. The most important expectation of body contouring surgery was improved appearance, followed by improved self-confidence and quality of life. Surplus skin resulting from gastric bypass surgery is a common issue that causes functional and aesthetic impairments in patients. Consequently, this increases the desire for body contouring surgery with high expectations for the aesthetic outcome as well as improved life satisfaction.
Lin, Muqing; Chan, Siwa; Chen, Jeon-Hor; Chang, Daniel; Nie, Ke; Chen, Shih-Ting; Lin, Cheng-Ju; Shih, Tzu-Ching; Nalcioglu, Orhan; Su, Min-Ying
2011-01-01
Quantitative breast density is known as a strong risk factor associated with the development of breast cancer. Measurement of breast density based on three-dimensional breast MRI may provide very useful information. One important step for quantitative analysis of breast density on MRI is the correction of field inhomogeneity to allow an accurate segmentation of the fibroglandular tissue (dense tissue). A new bias field correction method by combining the nonparametric nonuniformity normalization (N3) algorithm and fuzzy-C-means (FCM)-based inhomogeneity correction algorithm is developed in this work. The analysis is performed on non-fat-sat T1-weighted images acquired using a 1.5 T MRI scanner. A total of 60 breasts from 30 healthy volunteers was analyzed. N3 is known as a robust correction method, but it cannot correct a strong bias field on a large area. FCM-based algorithm can correct the bias field on a large area, but it may change the tissue contrast and affect the segmentation quality. The proposed algorithm applies N3 first, followed by FCM, and then the generated bias field is smoothed using Gaussian kernal and B-spline surface fitting to minimize the problem of mistakenly changed tissue contrast. The segmentation results based on the N3+FCM corrected images were compared to the N3 and FCM alone corrected images and another method, coherent local intensity clustering (CLIC), corrected images. The segmentation quality based on different correction methods were evaluated by a radiologist and ranked. The authors demonstrated that the iterative N3+FCM correction method brightens the signal intensity of fatty tissues and that separates the histogram peaks between the fibroglandular and fatty tissues to allow an accurate segmentation between them. In the first reading session, the radiologist found (N3+FCM > N3 > FCM) ranking in 17 breasts, (N3+FCM > N3 = FCM) ranking in 7 breasts, (N3+FCM = N3 > FCM) in 32 breasts, (N3+FCM = N3 = FCM) in 2 breasts, and (N3 > N3+FCM > FCM) in 2 breasts. The results of the second reading session were similar. The performance in each pairwise Wilcoxon signed-rank test is significant, showing N3+FCM superior to both N3 and FCM, and N3 superior to FCM. The performance of the new N3+FCM algorithm was comparable to that of CLIC, showing equivalent quality in 57/60 breasts. Choosing an appropriate bias field correction method is a very important preprocessing step to allow an accurate segmentation of fibroglandular tissues based on breast MRI for quantitative measurement of breast density. The proposed algorithm combining N3+FCM and CLIC both yield satisfactory results.
Shi, Hongli; Yang, Zhi; Luo, Shuqian
2017-01-01
The beam hardening artifact is one of most important modalities of metal artifact for polychromatic X-ray computed tomography (CT), which can impair the image quality seriously. An iterative approach is proposed to reduce beam hardening artifact caused by metallic components in polychromatic X-ray CT. According to Lambert-Beer law, the (detected) projections can be expressed as monotonic nonlinear functions of element geometry projections, which are the theoretical projections produced only by the pixel intensities (image grayscale) of certain element (component). With help of a prior knowledge on spectrum distribution of X-ray beam source and energy-dependent attenuation coefficients, the functions have explicit expressions. Newton-Raphson algorithm is employed to solve the functions. The solutions are named as the synthetical geometry projections, which are the nearly linear weighted sum of element geometry projections with respect to mean of each attenuation coefficient. In this process, the attenuation coefficients are modified to make Newton-Raphson iterative functions satisfy the convergence conditions of fixed pointed iteration(FPI) so that the solutions will approach the true synthetical geometry projections stably. The underlying images are obtained using the projections by general reconstruction algorithms such as the filtered back projection (FBP). The image gray values are adjusted according to the attenuation coefficient means to obtain proper CT numbers. Several examples demonstrate the proposed approach is efficient in reducing beam hardening artifacts and has satisfactory performance in the term of some general criteria. In a simulation example, the normalized root mean square difference (NRMSD) can be reduced 17.52% compared to a newest algorithm. Since the element geometry projections are free from the effect of beam hardening, the nearly linear weighted sum of them, the synthetical geometry projections, are almost free from the effect of beam hardening. By working out the synthetical geometry projections, the proposed approach becomes quite efficient in reducing beam hardening artifacts.
Pannell, J Scott; Santiago-Dieppa, David R; Wali, Arvin R; Hirshman, Brian R; Steinberg, Jeffrey A; Cheung, Vincent J; Oveisi, David; Hallstrom, Jon; Khalessi, Alexander A
2016-08-29
This study establishes performance metrics for angiography and neuroendovascular surgery procedures based on longitudinal improvement in individual trainees with differing levels of training and experience. Over the course of 30 days, five trainees performed 10 diagnostic angiograms, coiled 10 carotid terminus aneurysms in the setting of subarachnoid hemorrhage, and performed 10 left middle cerebral artery embolectomies on a Simbionix Angio Mentor™ simulator. All procedures were nonconsecutive. Total procedure time, fluoroscopy time, contrast dose, heart rate, blood pressures, medications administered, packing densities, the number of coils used, and the number of stent-retriever passes were recorded. Image quality was rated, and the absolute value of technically unsafe events was recorded. The trainees' device selection, macrovascular access, microvascular access, clinical management, and the overall performance of the trainee was rated during each procedure based on a traditional Likert scale score of 1=fail, 2=poor, 3=satisfactory, 4=good, and 5=excellent. These ordinal values correspond with published assessment scales on surgical technique. After performing five diagnostic angiograms and five embolectomies, all participants demonstrated marked decreases in procedure time, fluoroscopy doses, contrast doses, and adverse technical events; marked improvements in image quality, device selection, access scores, and overall technical performance were additionally observed (p < 0.05). Similarly, trainees demonstrated marked improvement in technical performance and clinical management after five coiling procedures (p < 0.05). However, trainees with less prior experience deploying coils continued to experience intra-procedural ruptures up to the eighth embolization procedure; this observation likely corresponded with less tactile procedural experience to an exertion of greater force than appropriate for coil placement. Trainees across all levels of training and prior experience demonstrated a significant performance improvement after completion of our simulator curriculum consisting of five diagnostic angiograms, five embolectomy cases, and 10 aneurysm coil embolizations.
Development of a Dual-PIV system for high-speed flow applications
NASA Astrophysics Data System (ADS)
Schreyer, Anne-Marie; Lasserre, Jean J.; Dupont, Pierre
2015-10-01
A new Dual-particle image velocimetry (Dual-PIV) system for application in supersonic flows was developed. The system was designed for shock wave/turbulent boundary layer interactions with separation. This type of flow places demanding requirements on the system, from the large range of characteristic frequencies O(100 Hz-100 kHz) to spatial and temporal resolutions necessary for the measurement of turbulent quantities (Dolling in AIAA J 39(8):1517-1531, 2001; Dupont et al. in J Fluid Mech 559:255-277, 2006; Smits and Dussauge in Turbulent shear layers in supersonic flow, 2nd edn. Springer, New York, 2006). While classic PIV systems using high-resolution CCD sensors allow high spatial resolution, these systems cannot provide the required temporal resolution. Existing high-speed PIV systems provide temporal and CMOS sensor resolutions, and even laser pulse energies, that are not adapted to our needs. The only obvious solution allowing sufficiently high spatial resolution, access to high frequencies, and a high laser pulse energy is a multi-frame system: a Dual-PIV system, consisting of two synchronized PIV systems observing the same field of view, will give access to temporal characteristics of the flow. The key technology of our system is frequency-based image separation: two lasers of different wavelengths illuminate the field of view. The cross-pollution with laser light from the respective other branches was quantified during system validation. The overall system noise was quantified, and the prevailing error of only 2 % reflects the good spatial and temporal alignment. The quality of the measurement system is demonstrated with some results on a subsonic jet flow including the spatio-temporal inter-correlation functions between the systems. First measurements in a turbulent flat-plate boundary layer at Mach 2 show the same satisfactory data quality and are also presented and discussed.
Guidance for Efficient Small Animal Imaging Quality Control.
Osborne, Dustin R; Kuntner, Claudia; Berr, Stuart; Stout, David
2017-08-01
Routine quality control is a critical aspect of properly maintaining high-performance small animal imaging instrumentation. A robust quality control program helps produce more reliable data both for academic purposes and as proof of system performance for contract imaging work. For preclinical imaging laboratories, the combination of costs and available resources often limits their ability to produce efficient and effective quality control programs. This work presents a series of simplified quality control procedures that are accessible to a wide range of preclinical imaging laboratories. Our intent is to provide minimum guidelines for routine quality control that can assist preclinical imaging specialists in setting up an appropriate quality control program for their facility.
Task-based measures of image quality and their relation to radiation dose and patient risk
Barrett, Harrison H.; Myers, Kyle J.; Hoeschen, Christoph; Kupinski, Matthew A.; Little, Mark P.
2015-01-01
The theory of task-based assessment of image quality is reviewed in the context of imaging with ionizing radiation, and objective figures of merit (FOMs) for image quality are summarized. The variation of the FOMs with the task, the observer and especially with the mean number of photons recorded in the image is discussed. Then various standard methods for specifying radiation dose are reviewed and related to the mean number of photons in the image and hence to image quality. Current knowledge of the relation between local radiation dose and the risk of various adverse effects is summarized, and some graphical depictions of the tradeoffs between image quality and risk are introduced. Then various dose-reduction strategies are discussed in terms of their effect on task-based measures of image quality. PMID:25564960
No-reference multiscale blur detection tool for content based image retrieval
NASA Astrophysics Data System (ADS)
Ezekiel, Soundararajan; Stocker, Russell; Harrity, Kyle; Alford, Mark; Ferris, David; Blasch, Erik; Gorniak, Mark
2014-06-01
In recent years, digital cameras have been widely used for image capturing. These devices are equipped in cell phones, laptops, tablets, webcams, etc. Image quality is an important component of digital image analysis. To assess image quality for these mobile products, a standard image is required as a reference image. In this case, Root Mean Square Error and Peak Signal to Noise Ratio can be used to measure the quality of the images. However, these methods are not possible if there is no reference image. In our approach, a discrete-wavelet transformation is applied to the blurred image, which decomposes into the approximate image and three detail sub-images, namely horizontal, vertical, and diagonal images. We then focus on noise-measuring the detail images and blur-measuring the approximate image to assess the image quality. We then compute noise mean and noise ratio from the detail images, and blur mean and blur ratio from the approximate image. The Multi-scale Blur Detection (MBD) metric provides both an assessment of the noise and blur content. These values are weighted based on a linear regression against full-reference y values. From these statistics, we can compare to normal useful image statistics for image quality without needing a reference image. We then test the validity of our obtained weights by R2 analysis as well as using them to estimate image quality of an image with a known quality measure. The result shows that our method provides acceptable results for images containing low to mid noise levels and blur content.
Rodríguez-Olivares, Ramón; El Faquir, Nahid; Rahhab, Zouhair; Maugenest, Anne-Marie; Van Mieghem, Nicolas M; Schultz, Carl; Lauritsch, Guenter; de Jaegere, Peter P T
2016-07-01
To study the determinants of image quality of rotational angiography using dedicated research prototype software for motion compensation without rapid ventricular pacing after the implantation of four commercially available catheter-based valves. Prospective observational study including 179 consecutive patients who underwent transcatheter aortic valve implantation (TAVI) with either the Medtronic CoreValve (MCS), Edward-SAPIEN Valve (ESV), Boston Sadra Lotus (BSL) or Saint-Jude Portico Valve (SJP) in whom rotational angiography (R-angio) with motion compensation 3D image reconstruction was performed. Image quality was evaluated from grade 1 (excellent image quality) to grade 5 (strongly degraded). Distinction was made between good (grades 1, 2) and poor image quality (grades 3-5). Clinical (gender, body mass index, Agatston score, heart rate and rhythm, artifacts), procedural (valve type) and technical variables (isocentricity) were related with the image quality assessment. Image quality was good in 128 (72 %) and poor in 51 (28 %) patients. By univariable analysis only valve type (BSL) and the presence of an artefact negatively affected image quality. By multivariate analysis (in which BMI was forced into the model) BSL valve (Odds 3.5, 95 % CI [1.3-9.6], p = 0.02), presence of an artifact (Odds 2.5, 95 % CI [1.2-5.4], p = 0.02) and BMI (Odds 1.1, 95 % CI [1.0-1.2], p = 0.04) were independent predictors of poor image quality. Rotational angiography with motion compensation 3D image reconstruction using a dedicated research prototype software offers good image quality for the evaluation of frame geometry after TAVI in the majority of patients. Valve type, presence of artifacts and higher BMI negatively affect image quality.
Use of animals in the development and control of viral vaccines.
Minor, P D
1996-01-01
Animal models were central to the development of poliovaccines and remain essential in some form in the routine quality control of both live and killed vaccines. The necessity of an animal model is illustrated by the examples of mumps and measles vaccines where the existing materials, while satisfactory, have a number of drawbacks and where changes in current practice raise concerns for safety and efficacy.
Comparison of the viewing wand and the BRW stereotaxy systems
NASA Astrophysics Data System (ADS)
Heiferman, Kenneth S.; Cramer, Kevin E.
1993-09-01
Intracranial lesions are invisible and exploration can be hazardous to the patient's postoperative quality of life. The first generation of neurosurgeons relied on their knowledge of neurology and anatomy to try to locate the patient's lesion. In general, this did not produce satisfactory results. Improvements in neuroradiology, neuroanesthesia, and neurosurgical techniques have diminished the proportion of the brain viewed as inoperable. These improvements have significantly improved patient outcomes.
Sun, H; Lau, K M; Fung, Y S
2010-05-07
Monitoring of trace impurities in electroplating bath is needed to meet EU requirements for WEEE and RoHS and for quality control of electrodeposits. Methods using IC and 100% aqueous CE buffer were found producing non-repeatable results attributed to interference of surfactants and major methanesulphonate anion. A new CE buffer containing 1.5mM tetraethylenepentaamine, 3mM 1,3,5-benzenetricarboxylic acid and 15 mM Tris in 20% (v/v) methanol at pH=8.4 was shown to enhance the separation window, reduce interaction between buffer and bath constituents, and give satisfactory repeatability with baseline separation for 14 organic and inorganic anions within 14 min, good repeatability for migration time (0.32-0.57% RSD), satisfactory peak area and peak height (2.9-4.5 and 3-4.7% respectively), low detection limit (S/N=2, 20-150 ppb), and wide working ranges (0.1-100 ppm). The CE buffer with 20% (v/v) methanol has demonstrated its capability for identifying anion impurities causing problem in aged tin bath and the use of only 10-fold dilution to produce reliable results for quality assessment in plating bath containing high surfactant additives. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Dreiling, Katharina; Montano, Diego; Poinstingl, Herbert; Müller, Tjark; Schiekirka-Schwake, Sarah; Anders, Sven; von Steinbüchel, Nicole; Raupach, Tobias
2017-08-01
Evaluation is an integral part of curriculum development in medical education. Given the peculiarities of bedside teaching, specific evaluation tools for this instructional format are needed. Development of these tools should be informed by appropriate frameworks. The purpose of this study was to develop a specific evaluation tool for bedside teaching based on the Stanford Faculty Development Program's clinical teaching framework. Based on a literature review yielding 47 evaluation items, an 18-item questionnaire was compiled and subsequently completed by undergraduate medical students at two German universities. Reliability and validity were assessed in an exploratory full information item factor analysis (study one) and a confirmatory factor analysis as well as a measurement invariance analysis (study two). The exploratory analysis involving 824 students revealed a three-factor structure. Reliability estimates of the subscales were satisfactory (α = 0.71-0.84). The model yielded satisfactory fit indices in the confirmatory factor analysis involving 1043 students. The new questionnaire is short and yet based on a widely-used framework for clinical teaching. The analyses presented here indicate good reliability and validity of the instrument. Future research needs to investigate whether feedback generated from this tool helps to improve teaching quality and student learning outcome.
Percutaneous cecostomy in the management of organic fecal incontinence in children
Donkol, Ragab Hani; Al-Nammi, Ahmed
2010-01-01
AIM: To assess the effectiveness and safety of imaging-guided percutaneous cecostomy in the management of pediatric patients with organic fecal incontinence. METHODS: Twenty three cecostomies were performed on 21 children with organic fecal incontinence (13 males, 8 females), aged from 5 to 16 years (mean 9.5 years). Thirteen patients had neurogenic fecal incontinence and 8 patients had anorectal anomalies. Procedures were performed under general anesthesia and fluoroscopic guidance. Effectiveness and complication data were obtained for at least 1 year after the procedure. RESULTS: Cecostomy was successful in 20 patients (primary technical success rate 95%). Cecostomy failed in one patient due to tube breakage (secondary technical success rate 100%). The tubes were in situ for an average of 18 mo (range 12-23 mo). Eighteen patients (87%) expressed satisfaction with the procedures. Resolution of soiling was achieved in all patients with neurogenic fecal incontinence (100%) and in 5 of 8 patients with anorectal anomalies (62.5%). Eleven patients (52%) experienced minor problems. No major complications were noted. CONCLUSION: Percutaneous cecostomy improves the quality of life in children with organic fecal incontinence. A satisfactory outcome is more prevalent in patients with neurogenic fecal incontinence than anorectal anomalies. PMID:21225001
An integrated system for the online monitoring of particle therapy treatment accuracy
NASA Astrophysics Data System (ADS)
Fiorina, E.; INSIDE Collaboration
2016-07-01
Quality assurance in hadrontherapy remains an open issue that can be addressed with reliable monitoring of treatment accuracy. The INSIDE (INnovative SolutIons for DosimEtry in hadrontherapy) project aims to develop an integrated online monitoring system based on two dedicated PET panels and a tracking system, called Dose Profiler. The proposed solution is designed to operate in-beam and provide an immediate feedback on the particle range acquiring both photons produced by β+ decays and prompt secondary particle signals. Monte Carlo simulations cover an important role both in the system development, by confirming the design feasibility, and in the system operation, by understanding data. A FLUKA-based integrated simulation was developed taking into account the hadron beam structure, the phantom/patient features and the PET detector and Dose Profiler specifications. In addition, to reduce simulation time in signal generation on PET detectors, a two-step technique has been implemented and validated. The first PET modules were tested in May 2015 at the Centro Nazionale Adroterapia Oncologica (CNAO) in Pavia (Italy) with very satisfactory results: in-spill, inter-spill and post-treatment PET images were reconstructed and a quantitative agreement between data and simulation was found.
Digital processing of radiographic images from PACS to publishing.
Christian, M E; Davidson, H C; Wiggins, R H; Berges, G; Cannon, G; Jackson, G; Chapman, B; Harnsberger, H R
2001-03-01
Several studies have addressed the implications of filmless radiologic imaging on telemedicine, diagnostic ability, and electronic teaching files. However, many publishers still require authors to submit hard-copy images for publication of articles and textbooks. This study compares the quality digital images directly exported from picture archive and communications systems (PACS) to images digitized from radiographic film. The authors evaluated the quality of publication-grade glossy photographs produced from digital radiographic images using 3 different methods: (1) film images digitized using a desktop scanner and then printed, (2) digital images obtained directly from PACS then printed, and (3) digital images obtained from PACS and processed to improve sharpness prior to printing. Twenty images were printed using each of the 3 different methods and rated for quality by 7 radiologists. The results were analyzed for statistically significant differences among the image sets. Subjective evaluations of the filmless images found them to be of equal or better quality than the digitized images. Direct electronic transfer of PACS images reduces the number of steps involved in creating publication-quality images as well as providing the means to produce high-quality radiographic images in a digital environment.
Human visual system consistent quality assessment for remote sensing image fusion
NASA Astrophysics Data System (ADS)
Liu, Jun; Huang, Junyi; Liu, Shuguang; Li, Huali; Zhou, Qiming; Liu, Junchen
2015-07-01
Quality assessment for image fusion is essential for remote sensing application. Generally used indices require a high spatial resolution multispectral (MS) image for reference, which is not always readily available. Meanwhile, the fusion quality assessments using these indices may not be consistent with the Human Visual System (HVS). As an attempt to overcome this requirement and inconsistency, this paper proposes an HVS-consistent image fusion quality assessment index at the highest resolution without a reference MS image using Gaussian Scale Space (GSS) technology that could simulate the HVS. The spatial details and spectral information of original and fused images are first separated in GSS, and the qualities are evaluated using the proposed spatial and spectral quality index respectively. The overall quality is determined without a reference MS image by a combination of the proposed two indices. Experimental results on various remote sensing images indicate that the proposed index is more consistent with HVS evaluation compared with other widely used indices that may or may not require reference images.
Low-cost oblique illumination: an image quality assessment.
Ruiz-Santaquiteria, Jesus; Espinosa-Aranda, Jose Luis; Deniz, Oscar; Sanchez, Carlos; Borrego-Ramos, Maria; Blanco, Saul; Cristobal, Gabriel; Bueno, Gloria
2018-01-01
We study the effectiveness of several low-cost oblique illumination filters to improve overall image quality, in comparison with standard bright field imaging. For this purpose, a dataset composed of 3360 diatom images belonging to 21 taxa was acquired. Subjective and objective image quality assessments were done. The subjective evaluation was performed by a group of diatom experts by psychophysical test where resolution, focus, and contrast were assessed. Moreover, some objective nonreference image quality metrics were applied to the same image dataset to complete the study, together with the calculation of several texture features to analyze the effect of these filters in terms of textural properties. Both image quality evaluation methods, subjective and objective, showed better results for images acquired using these illumination filters in comparison with the no filtered image. These promising results confirm that this kind of illumination filters can be a practical way to improve the image quality, thanks to the simple and low cost of the design and manufacturing process. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).
NASA Astrophysics Data System (ADS)
Titi Purwantini, V.; Sutanto, Yusuf
2018-05-01
This research is to create a model of flood control in the city of Surakarta using Servqual method and Importance Performance Analysis. Service quality is generally defined as the overall assessment of a service by the customersor the extent to which a service meets customer’s needs or expectations. The purpose of this study is to find the first model of flood control that is appropriate to the condition of the community. Surakarta This means looking for a model that can provide satisfactory service for the people of Surakarta who are in the location of the flood. The second is to find the right model to improve service performance of Surakarta City Government in serving the people in flood location. The method used to determine the satisfaction of the public on the quality of service is to see the difference in the quality of service expected by the community with the reality. This method is Servqual Method While to assess the performance of city government officials is by comparing the actual performance with the quality of services provided, this method is This means looking for a model that can provide satisfactory service for the people of Surakarta who are in the location of the flood.The second is to find the right model to improve service performance of Surakarta City Government in serving the people in flood location. The method used to determine the satisfaction of the public on the quality of service is to see the difference in the quality of service expected by the community with the reality. This method is Servqual Method While to assess the performance of city government officials is by comparing the actual performance with the quality of services provided, this method is Importance Performance Analysis. Samples were people living in flooded areas in the city of Surakarta. Result this research is Satisfaction = Responsiveness+ Realibility + Assurance + Empathy+ Tangible (Servqual Model) and Importance Performance Analysis is From Cartesian diagram can be made Flood Control Formula as follow: Food Control = High performance
NASA Astrophysics Data System (ADS)
Hoko, Zvikomborero
Zimbabwe generally receives an average rainfall of 675 mm per annum of which only a maximum of 10% finds its way to rivers as runoff. Gokwe, Nkayi, Lupane and Mwenezi are some of the driest districts in Zimbabwe having mean annual runoffs (MAR) in the range 17-70 mm. River flows especially in Nkayi and Lupane are seasonal and often dry in the period June to November every year. The Kalahari sands predominantly found in such areas as Gokwe, Nkayi, and Lupane promote rapid percolation of rainwater leaving little runoff. The main source of water for domestic purposes in these areas is groundwater with very little reliance on surface water. This study analyzed the water quality of water points in Gokwe South, Nkayi, Lupane, and Mwenezi districts. Parameters analyzed were pH, temperature, dissolved oxygen (DO), turbidity and electrical conductivity (EC). Water quality perceptions from the villagers and the research team were investigated and possible correlations studied. Water quality perceptions included, taste and soap consumption and colour. The uses of the water at domestic level as well as available alternatives to borehole water were investigated. The pH generally ranged from 6.5 to 8.0, which is within the Canadian guidelines. DO was 0.3-5.9 mg/l while turbidity ranged from 0 to 259 NTU with Mwenezi having the highest turbidity value. Conductivity ranged from 70 to 9800 μS/cm with the lowest and highest values recorded in Gokwe and Mwenezi. It was found out that the water quality in terms of taste and odour was 97% satisfactory for Gokwe South, 85% Nkayi, 64% Lupane, and 62% for Mwenezi. High soap consumption which is related to hardness was perceived to be least in Lupane (14%) and highest in Mwenezi with 81%. In general taste complaints also corresponded to high soap consumption but the opposite was not true. It was observed that there was no clear correlation between the quality parameters studied and perceived quality as for example satisfactory taste responses were obtained at EC values higher than the threshold minimum value for objection.
LANDSAT-1 and LANDSAT-2 flight evaluation report
NASA Technical Reports Server (NTRS)
1976-01-01
The LANDSAT-1 spacecraft was launched from the Western Test Range on 23 July 1972, at 18:08:06.508Z. The launch and orbital injection phase of the space flight was nominal and deployment of the spacecraft followed predictions. Orbital operations of the spacecraft and payload subsystems were satisfactory through Orbit 147, after which an internal short circuit disabled one of the Wideband Video Tape Recorders (WBVTR-2). Operations resumed until Orbit 196, when the Return Beam Vidicon failed to respond when commanded off. The RBV was commanded off via alternate commands. LANDSAT-1 continued to perform its imaging mission with the Multispectral Scanner and the remaining Wideband Video Tape Recorder providing image data.
Huh, S J; Shirato, H; Hashimoto, S; Shimizu, S; Kim, D Y; Ahn, Y C; Choi, D; Miyasaka, K; Mizuno, J
2000-07-01
This study introduces the integrated service digital network (ISDN)-based international teleradiotherapy system (THERAPIS) in radiation oncology between hospitals in Seoul, South Korea and in Sapporo, Japan. THERAPIS has the following functions: (1) exchange of patient's image data, (2) real-time teleconference, and (3) communication of the treatment planning, dose calculation and distribution, and of portal verification images between the remote hospitals. Our preliminary results of applications on eight patients demonstrated that the international telecommunication using THERAPIS was clinically useful and satisfactory with sufficient bandwidth for the transfer of patient data for clinical use in radiation oncology.
NASA Astrophysics Data System (ADS)
Tingberg, Anders Martin
Optimisation in diagnostic radiology requires accurate methods for determination of patient absorbed dose and clinical image quality. Simple methods for evaluation of clinical image quality are at present scarce and this project aims at developing such methods. Two methods are used and further developed; fulfillment of image criteria (IC) and visual grading analysis (VGA). Clinical image quality descriptors are defined based on these two methods: image criteria score (ICS) and visual grading analysis score (VGAS), respectively. For both methods the basis is the Image Criteria of the ``European Guidelines on Quality Criteria for Diagnostic Radiographic Images''. Both methods have proved to be useful for evaluation of clinical image quality. The two methods complement each other: IC is an absolute method, which means that the quality of images of different patients and produced with different radiographic techniques can be compared with each other. The separating power of IC is, however, weaker than that of VGA. VGA is the best method for comparing images produced with different radiographic techniques and has strong separating power, but the results are relative, since the quality of an image is compared to the quality of a reference image. The usefulness of the two methods has been verified by comparing the results from both of them with results from a generally accepted method for evaluation of clinical image quality, receiver operating characteristics (ROC). The results of the comparison between the two methods based on visibility of anatomical structures and the method based on detection of pathological structures (free-response forced error) indicate that the former two methods can be used for evaluation of clinical image quality as efficiently as the method based on ROC. More studies are, however, needed for us to be able to draw a general conclusion, including studies of other organs, using other radiographic techniques, etc. The results of the experimental evaluation of clinical image quality are compared with physical quantities calculated with a theoretical model based on a voxel phantom, and correlations are found. The results demonstrate that the computer model can be a useful toot in planning further experimental studies.
Research on assessment and improvement method of remote sensing image reconstruction
NASA Astrophysics Data System (ADS)
Sun, Li; Hua, Nian; Yu, Yanbo; Zhao, Zhanping
2018-01-01
Remote sensing image quality assessment and improvement is an important part of image processing. Generally, the use of compressive sampling theory in remote sensing imaging system can compress images while sampling which can improve efficiency. A method of two-dimensional principal component analysis (2DPCA) is proposed to reconstruct the remote sensing image to improve the quality of the compressed image in this paper, which contain the useful information of image and can restrain the noise. Then, remote sensing image quality influence factors are analyzed, and the evaluation parameters for quantitative evaluation are introduced. On this basis, the quality of the reconstructed images is evaluated and the different factors influence on the reconstruction is analyzed, providing meaningful referential data for enhancing the quality of remote sensing images. The experiment results show that evaluation results fit human visual feature, and the method proposed have good application value in the field of remote sensing image processing.
Thomas, Christoph; Brodoefel, Harald; Tsiflikas, Ilias; Bruckner, Friederike; Reimann, Anja; Ketelsen, Dominik; Drosch, Tanja; Claussen, Claus D; Kopp, Andreas; Heuschmid, Martin; Burgstahler, Christof
2010-02-01
To prospectively evaluate the influence of the clinical pretest probability assessed by the Morise score onto image quality and diagnostic accuracy in coronary dual-source computed tomography angiography (DSCTA). In 61 patients, DSCTA and invasive coronary angiography were performed. Subjective image quality and accuracy for stenosis detection (>50%) of DSCTA with invasive coronary angiography as gold standard were evaluated. The influence of pretest probability onto image quality and accuracy was assessed by logistic regression and chi-square testing. Correlations of image quality and accuracy with the Morise score were determined using linear regression. Thirty-eight patients were categorized into the high, 21 into the intermediate, and 2 into the low probability group. Accuracies for the detection of significant stenoses were 0.94, 0.97, and 1.00, respectively. Logistic regressions and chi-square tests showed statistically significant correlations between Morise score and image quality (P < .0001 and P < .001) and accuracy (P = .0049 and P = .027). Linear regression revealed a cutoff Morise score for a good image quality of 16 and a cutoff for a barely diagnostic image quality beyond the upper Morise scale. Pretest probability is a weak predictor of image quality and diagnostic accuracy in coronary DSCTA. A sufficient image quality for diagnostic images can be reached with all pretest probabilities. Therefore, coronary DSCTA might be suitable also for patients with a high pretest probability. Copyright 2010 AUR. Published by Elsevier Inc. All rights reserved.
Side-looking airborne radar image interpretation and geological mapping: Problems and results
NASA Technical Reports Server (NTRS)
Scanvic, J. Y.; Soubari, E. H.
1980-01-01
Geological experiments and surveys conducted by BRGM and GDTA members to evaluate interest in SLAR image interpretation are summarized. Two surveys were selected for presentation: Les Vans (Massif central, France) and Guyana (South America). They have permitted a comparison between different types of SLAR: Goodyear, Motorola, JPL, and Vigie in term of lithological and structural applications. On the Les Vans test site conclusions reached concern radiometry, which is better on L-band imagery, polarization, HV being more useful than HH for geological mapping in an L-band system, wavelength and illuminations. Over Guyana, the use of Goodyear X-band SLAR enables satisfactory geological and structural mapping under heavy equatorial forest with cloud cover conditions. A differential program was developed for fracture filtering and image enhancement with a coherent light laser, and significant results were obtained.
Patwary, Nurmohammed; Doblas, Ana; Preza, Chrysanthe
2018-01-01
The performance of structured illumination microscopy (SIM) is hampered in many biological applications due to the inability to modulate the light when imaging deep into the sample. This is in part because sample-induced aberration reduces the modulation contrast of the structured pattern. In this paper, we present an image restoration approach suitable for processing raw incoherent-grid-projection SIM data with a low fringe contrast. Restoration results from simulated and experimental ApoTome SIM data show results with improved signal-to-noise ratio (SNR) and optical sectioning compared to the results obtained from existing methods, such as 2D demodulation and 3D SIM deconvolution. Our proposed method provides satisfactory results (quantified by the achieved SNR and normalized mean square error) even when the modulation contrast of the illumination pattern is as low as 7%. PMID:29675307
Earth Resources Technology Satellite data collection project, ERTS - Bolivia. [thematic mapping
NASA Technical Reports Server (NTRS)
Brockmann, C. E.
1974-01-01
The Earth Resources Technology Satellite program of Bolivia has developed a multidisciplinary project to carry out investigations in cartography and to prepare various thematic maps. In cartography, investigations are being carried out with the ERTS-1 images and with existing maps, to determine their application to the preparation of new cartographic products on one hand and on the other to map those regions where the cartography is still deficient. The application of the MSS images to the geological mapping has given more than satisfactory results. Working with conventional photointerpretation, it has been possible to prepare regional geological maps, tectonic maps, studies relative to mining, geomorphological maps, studies relative to petroleum exploration, volcanological maps and maps of hydrologic basins. In agriculture, the ERTS images are used to study land classification and forest and soils mapping.
Modified-BRISQUE as no reference image quality assessment for structural MR images.
Chow, Li Sze; Rajagopal, Heshalini
2017-11-01
An effective and practical Image Quality Assessment (IQA) model is needed to assess the image quality produced from any new hardware or software in MRI. A highly competitive No Reference - IQA (NR - IQA) model called Blind/Referenceless Image Spatial Quality Evaluator (BRISQUE) initially designed for natural images were modified to evaluate structural MR images. The BRISQUE model measures the image quality by using the locally normalized luminance coefficients, which were used to calculate the image features. The modified-BRISQUE model trained a new regression model using MR image features and Difference Mean Opinion Score (DMOS) from 775 MR images. Two types of benchmarks: objective and subjective assessments were used as performance evaluators for both original and modified-BRISQUE models. There was a high correlation between the modified-BRISQUE with both benchmarks, and they were higher than those for the original BRISQUE. There was a significant percentage improvement in their correlation values. The modified-BRISQUE was statistically better than the original BRISQUE. The modified-BRISQUE model can accurately measure the image quality of MR images. It is a practical NR-IQA model for MR images without using reference images. Copyright © 2017 Elsevier Inc. All rights reserved.
Automated segmentation of three-dimensional MR brain images
NASA Astrophysics Data System (ADS)
Park, Jonggeun; Baek, Byungjun; Ahn, Choong-Il; Ku, Kyo Bum; Jeong, Dong Kyun; Lee, Chulhee
2006-03-01
Brain segmentation is a challenging problem due to the complexity of the brain. In this paper, we propose an automated brain segmentation method for 3D magnetic resonance (MR) brain images which are represented as a sequence of 2D brain images. The proposed method consists of three steps: pre-processing, removal of non-brain regions (e.g., the skull, meninges, other organs, etc), and spinal cord restoration. In pre-processing, we perform adaptive thresholding which takes into account variable intensities of MR brain images corresponding to various image acquisition conditions. In segmentation process, we iteratively apply 2D morphological operations and masking for the sequences of 2D sagittal, coronal, and axial planes in order to remove non-brain tissues. Next, final 3D brain regions are obtained by applying OR operation for segmentation results of three planes. Finally we reconstruct the spinal cord truncated during the previous processes. Experiments are performed with fifteen 3D MR brain image sets with 8-bit gray-scale. Experiment results show the proposed algorithm is fast, and provides robust and satisfactory results.
No-reference quality assessment based on visual perception
NASA Astrophysics Data System (ADS)
Li, Junshan; Yang, Yawei; Hu, Shuangyan; Zhang, Jiao
2014-11-01
The visual quality assessment of images/videos is an ongoing hot research topic, which has become more and more important for numerous image and video processing applications with the rapid development of digital imaging and communication technologies. The goal of image quality assessment (IQA) algorithms is to automatically assess the quality of images/videos in agreement with human quality judgments. Up to now, two kinds of models have been used for IQA, namely full-reference (FR) and no-reference (NR) models. For FR models, IQA algorithms interpret image quality as fidelity or similarity with a perfect image in some perceptual space. However, the reference image is not available in many practical applications, and a NR IQA approach is desired. Considering natural vision as optimized by the millions of years of evolutionary pressure, many methods attempt to achieve consistency in quality prediction by modeling salient physiological and psychological features of the human visual system (HVS). To reach this goal, researchers try to simulate HVS with image sparsity coding and supervised machine learning, which are two main features of HVS. A typical HVS captures the scenes by sparsity coding, and uses experienced knowledge to apperceive objects. In this paper, we propose a novel IQA approach based on visual perception. Firstly, a standard model of HVS is studied and analyzed, and the sparse representation of image is accomplished with the model; and then, the mapping correlation between sparse codes and subjective quality scores is trained with the regression technique of least squaresupport vector machine (LS-SVM), which gains the regressor that can predict the image quality; the visual metric of image is predicted with the trained regressor at last. We validate the performance of proposed approach on Laboratory for Image and Video Engineering (LIVE) database, the specific contents of the type of distortions present in the database are: 227 images of JPEG2000, 233 images of JPEG, 174 images of White Noise, 174 images of Gaussian Blur, 174 images of Fast Fading. The database includes subjective differential mean opinion score (DMOS) for each image. The experimental results show that the proposed approach not only can assess many kinds of distorted images quality, but also exhibits a superior accuracy and monotonicity.
Content-based cell pathology image retrieval by combining different features
NASA Astrophysics Data System (ADS)
Zhou, Guangquan; Jiang, Lu; Luo, Limin; Bao, Xudong; Shu, Huazhong
2004-04-01
Content Based Color Cell Pathology Image Retrieval is one of the newest computer image processing applications in medicine. Recently, some algorithms have been developed to achieve this goal. Because of the particularity of cell pathology images, the result of the image retrieval based on single characteristic is not satisfactory. A new method for pathology image retrieval by combining color, texture and morphologic features to search cell images is proposed. Firstly, nucleus regions of leukocytes in images are automatically segmented by K-mean clustering method. Then single leukocyte region is detected by utilizing thresholding algorithm segmentation and mathematics morphology. The features that include color, texture and morphologic features are extracted from single leukocyte to represent main attribute in the search query. The features are then normalized because the numerical value range and physical meaning of extracted features are different. Finally, the relevance feedback system is introduced. So that the system can automatically adjust the weights of different features and improve the results of retrieval system according to the feedback information. Retrieval results using the proposed method fit closely with human perception and are better than those obtained with the methods based on single feature.
Kim, Dong-Keun; Yoo, Sun K; Kim, Sun H
2005-01-01
The instant transmission of radiological images may be important for making rapid clinical decisions about emergency patients. We have examined an instant image transfer system based on a personal digital assistant (PDA) phone with a built-in camera. Images displayed on a picture archiving and communication systems (PACS) monitor can be captured by the camera in the PDA phone directly. Images can then be transmitted from an emergency centre to a remote physician via a wireless high-bandwidth network (CDMA 1 x EVDO). We reviewed the radiological lesions in 10 normal and 10 abnormal cases produced by modalities such as computerized tomography (CT), magnetic resonance (MR) and digital angiography. The images were of 24-bit depth and 1,144 x 880, 1,120 x 840, 1,024 x 768, 800 x 600, 640 x 480 and 320 x 240 pixels. Three neurosurgeons found that for satisfactory remote consultation a minimum size of 640 x 480 pixels was required for CT and MR images and 1,024 x 768 pixels for angiography images. Although higher resolution produced higher clinical satisfaction, it also required more transmission time. At the limited bandwidth employed, higher resolutions could not be justified.
A comparison of image processing techniques for bird recognition.
Nadimpalli, Uma D; Price, Randy R; Hall, Steven G; Bomma, Pallavi
2006-01-01
Bird predation is one of the major concerns for fish culture in open ponds. A novel method for dispersing birds is the use of autonomous vehicles. Image recognition software can improve their efficiency. Several image processing techniques for recognition of birds have been tested. A series of morphological operations were implemented. We divided images into 3 types, Type 1, Type 2, and Type 3, based on the level of difficulty of recognizing birds. Type 1 images were clear; Type 2 images were medium clear, and Type 3 images were unclear. Local thresholding has been implemented using HSV (Hue, Saturation, and Value), GRAY, and RGB (Red, Green, and Blue) color models on all three sections of images and results were tabulated. Template matching using normal correlation and artificial neural networks (ANN) are the other methods that have been developed in this study in addition to image morphology. Template matching produced satisfactory results irrespective of the difficulty level of images, but artificial neural networks produced accuracies of 100, 60, and 50% on Type 1, Type 2, and Type 3 images, respectively. Correct classification rate can be increased by further training. Future research will focus on testing the recognition algorithms in natural or aquacultural settings on autonomous boats. Applications of such techniques to industrial, agricultural, or related areas are additional future possibilities.
34 CFR 668.34 - Satisfactory academic progress.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 34 Education 3 2013-07-01 2013-07-01 false Satisfactory academic progress. 668.34 Section 668.34... Satisfactory academic progress. (a) Satisfactory academic progress policy. An institution must establish a reasonable satisfactory academic progress policy for determining whether an otherwise eligible student is...
34 CFR 668.34 - Satisfactory academic progress.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 34 Education 3 2014-07-01 2014-07-01 false Satisfactory academic progress. 668.34 Section 668.34... Satisfactory academic progress. (a) Satisfactory academic progress policy. An institution must establish a reasonable satisfactory academic progress policy for determining whether an otherwise eligible student is...
34 CFR 668.34 - Satisfactory academic progress.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 34 Education 3 2012-07-01 2012-07-01 false Satisfactory academic progress. 668.34 Section 668.34... Satisfactory academic progress. (a) Satisfactory academic progress policy. An institution must establish a reasonable satisfactory academic progress policy for determining whether an otherwise eligible student is...
34 CFR 668.34 - Satisfactory academic progress.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 34 Education 3 2011-07-01 2011-07-01 false Satisfactory academic progress. 668.34 Section 668.34... Satisfactory academic progress. (a) Satisfactory academic progress policy. An institution must establish a reasonable satisfactory academic progress policy for determining whether an otherwise eligible student is...
Backward Registration Based Aspect Ratio Similarity (ARS) for Image Retargeting Quality Assessment.
Zhang, Yabin; Fang, Yuming; Lin, Weisi; Zhang, Xinfeng; Li, Leida
2016-06-28
During the past few years, there have been various kinds of content-aware image retargeting operators proposed for image resizing. However, the lack of effective objective retargeting quality assessment metrics limits the further development of image retargeting techniques. Different from traditional Image Quality Assessment (IQA) metrics, the quality degradation during image retargeting is caused by artificial retargeting modifications, and the difficulty for Image Retargeting Quality Assessment (IRQA) lies in the alternation of the image resolution and content, which makes it impossible to directly evaluate the quality degradation like traditional IQA. In this paper, we interpret the image retargeting in a unified framework of resampling grid generation and forward resampling. We show that the geometric change estimation is an efficient way to clarify the relationship between the images. We formulate the geometric change estimation as a Backward Registration problem with Markov Random Field (MRF) and provide an effective solution. The geometric change aims to provide the evidence about how the original image is resized into the target image. Under the guidance of the geometric change, we develop a novel Aspect Ratio Similarity metric (ARS) to evaluate the visual quality of retargeted images by exploiting the local block changes with a visual importance pooling strategy. Experimental results on the publicly available MIT RetargetMe and CUHK datasets demonstrate that the proposed ARS can predict more accurate visual quality of retargeted images compared with state-of-the-art IRQA metrics.
Nyangara, Florence M; Hai, Tajrina; Zalisk, Kirsten; Ozor, Lynda; Ufere, Joy; Isiguzo, Chinwoke; Abubakar, Ibrahim Ndaliman
2018-05-01
Decision makers are searching for reliable data and best practices to support the implementation and scale-up of the integrated community case management (iCCM) programs in underserved areas to reduce under-five mortality in low-income countries. This study assesses data quality and reporting systems of the World Health Organization supported Rapid Access Expansion program implementing iCCM in Abia and Niger States, Nigeria. This cross-sectional study used data from 16 primary health facilities in both states. Data were collected through review of registers and monthly summary reports of 140 community-oriented resource persons (CORPs), assessments of the five dimensions of the data reporting systems and 46 key informant interviews with stakeholders. Data quality was assessed by availability, completeness and consistency. Each component of the reporting system was assessed on a 3-point scale (weak, satisfactory and strong). Results show that both the structure, functions and capabilities, as well as data collection and reporting tools dimensions of the reporting system were strong, scoring (2.80, 2.73) for Abia and (2.88, 2.75) for Niger, respectively. Data management processes and links with national reporting system components scored low 2 s, indicating fair strength. Data availability, completeness and consistency were found to be good, an indication of adequate training and supervision of CORPs and community health extension workers. Indicator definitions and reporting guidelines were the weakest dimension of the system due to lack of data reporting guidelines in both states. In conclusion, the results indicate satisfactory data reporting systems and good quality data during early implementation of iCCM programs in the two states. Hence, countries planning to adopt and implement iCCM programs should first develop structures, establish national standardized tools for collecting and reporting data, provide for adequate training and supervision of community health workers and develop reporting guidelines for all reporting levels to ensure data quality.
Ground-water quality in east-central New Jersey, and a plan for sampling networks
Harriman, D.A.; Sargent, B.P.
1985-01-01
Groundwater quality was evaluated in seven confined aquifers and the water table aquifer in east-central New Jersey based on 237 analyses of samples collected in 1981-82, and 225 older analyses. Investigation of the effect of land use on water quality and several sampling network proposals for the region are reported. Generally, water in the confined aquifers is of satisfactory quality for human consumption and most other uses. Iron (Fe) and manganese (Mn) concentrations exceed U.S. EPA drinking water standards in some wells screened in the Potomac-Raritan-Magothy aquifer system. Sodium (Na) concentrations in samples from three wells more than 800 ft deep in the Englishtown aquifer exceed the standard. Iron and Mn concentrations in this aquifer may also exceed the standards. Iron concentrations in the Wenonah-Mount Laurel aquifer exceed the standard. Based on 15 analyses of water from the Vincetown aquifer, Mn is the only constituent that exceeds the drinking water standard. In the Manasquan aquifer, 4 of the 16 Na determinations exceed the standard, and 8 of 16 Fe determinations exceed the standard. Water quality in the Atlantic City 800-ft sand is generally satisfactory. However, 12 Fe and 1 of 12 Mn determinations exceed the standards. For the Rio Grande water-bearing zone, 1 of 3 Fe determinations exceed the standard. The Kirkwood-Cohansey aquifer system (the water table aquifer) was the most thoroughly sampled (249 chemical analyses from 209 wells). Dissolved solids, chloride, Fe, nitrate, and Mn concentrations exceed drinking water standards in some areas. The results of chi-square tests of constituent distributions based on analyses from 158 wells in the water table aquifer indicate that calcium is higher in industrial and commercial areas; and Mg, chloride, and nitrate-plus-nitrite is higher in residential areas. (Author 's abstract)
Validation of the Kohnen Restless Legs Syndrome-Quality of Life instrument.
Kohnen, Ralf; Martinez-Martin, Pablo; Benes, Heike; Trenkwalder, Claudia; Högl, Birgit; Dunkl, Elmar; Walters, Arthur S
2016-08-01
Due to the symptoms and the sleep disturbances it causes, Restless Legs Syndrome (RLS) has a negative impact on quality of life. Measurement of such impact can be performed by means of questionnaires, such as the Kohnen Restless Legs Syndrome-Quality of Life questionnaire (KRLS-QoL), a specific 12-item instrument that is self-applied by patients. The present study is aimed at performing a first formal validation study of this instrument. Eight hundred ninety-one patients were included for analysis. RLS severity was assessed by the International Restless Legs Scale (IRLS), Restless Legs Syndrome-6 scales (RLS-6), and Clinical Global Impression of Severity. In addition the Epworth Sleepiness Scale (ESS) was assessed. Acceptability, dimensionality, scaling assumptions, reliability, precision, hypotheses-related validity, and responsiveness were tested. There were missing data in 3.58% patients. Floor and ceiling effects were low for the subscales, global evaluation, and summary index derived from items 1 to 11 after checking that scaling assumptions were met. Exploratory parallel factor analysis showed that the KRLS-QoL may be deemed unidimensional, ie, that all components of the scale are part of one overall general quality of life factor. Indexes of internal consistency (alpha = 0.88), item-total correlation (r S = 0.32-0.71), item homogeneity coefficient (0.41), and scale stability (ICC = 0.73) demonstrated a satisfactory reliability of the KRLS-QoL. Moderate or high correlations were obtained between KRLS-QoL scores and the IRLS, some components of the RLS-6, inter-KRLS-QoL domains, and global evaluations. Known-groups validity for severity levels grouping and responsiveness analysis results were satisfactory, the latter showing higher magnitudes of response for treated than for placebo arms. The KRLS-QoL was proven an acceptable, reliable, valid, and responsive measure to assess the impact of the RLS on quality of life. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Image quality assessment using deep convolutional networks
NASA Astrophysics Data System (ADS)
Li, Yezhou; Ye, Xiang; Li, Yong
2017-12-01
This paper proposes a method of accurately assessing image quality without a reference image by using a deep convolutional neural network. Existing training based methods usually utilize a compact set of linear filters for learning features of images captured by different sensors to assess their quality. These methods may not be able to learn the semantic features that are intimately related with the features used in human subject assessment. Observing this drawback, this work proposes training a deep convolutional neural network (CNN) with labelled images for image quality assessment. The ReLU in the CNN allows non-linear transformations for extracting high-level image features, providing a more reliable assessment of image quality than linear filters. To enable the neural network to take images of any arbitrary size as input, the spatial pyramid pooling (SPP) is introduced connecting the top convolutional layer and the fully-connected layer. In addition, the SPP makes the CNN robust to object deformations to a certain extent. The proposed method taking an image as input carries out an end-to-end learning process, and outputs the quality of the image. It is tested on public datasets. Experimental results show that it outperforms existing methods by a large margin and can accurately assess the image quality on images taken by different sensors of varying sizes.
Podkowinski, Dominika; Sharian Varnousfaderani, Ehsan; Simader, Christian; Bogunovic, Hrvoje; Philip, Ana-Maria; Gerendas, Bianca S.
2017-01-01
Background and Objective To determine optimal image averaging settings for Spectralis optical coherence tomography (OCT) in patients with and without cataract. Study Design/Material and Methods In a prospective study, the eyes were imaged before and after cataract surgery using seven different image averaging settings. Image quality was quantitatively evaluated using signal-to-noise ratio, distinction between retinal layer image intensity distributions, and retinal layer segmentation performance. Measures were compared pre- and postoperatively across different degrees of averaging. Results 13 eyes of 13 patients were included and 1092 layer boundaries analyzed. Preoperatively, increasing image averaging led to a logarithmic growth in all image quality measures up to 96 frames. Postoperatively, increasing averaging beyond 16 images resulted in a plateau without further benefits to image quality. Averaging 16 frames postoperatively provided comparable image quality to 96 frames preoperatively. Conclusion In patients with clear media, averaging 16 images provided optimal signal quality. A further increase in averaging was only beneficial in the eyes with senile cataract. However, prolonged acquisition time and possible loss of details have to be taken into account. PMID:28630764
38 CFR 21.8360 - Satisfactory conduct and cooperation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Satisfactory conduct and... Children of Vietnam Veterans-Spina Bifida and Covered Birth Defects Satisfactory Conduct and Cooperation § 21.8360 Satisfactory conduct and cooperation. The provisions for satisfactory conduct and cooperation...
Surgical Treatment of Cardiac Echinococcosis: Report of Nine Cases
Papo, Isidor; Ginsberg, Ervin; Albreht, Miša; Martinović, Nebojša; Sokolić, Josip
1982-01-01
We reviewed the results in eight patients followed from 10 months to 22 years after one-stage surgery for removal of primary and secondary myocardial and pericardial hydatid cysts. The results were satisfactory in eight patients who survived the operation. One patient, however, with recurrent myocardial echinococcosis, pulmonary embolization, and sepis died at reoperation. The series was analyzed with reference to the surgical treatment and world-wide experience of complicated cardiac echinococcosis. Images PMID:15226804
Alonso-Caneiro, David; Sampson, Danuta M.; Chew, Avenell L.; Collins, Michael J.; Chen, Fred K.
2018-01-01
Adaptive optics flood illumination ophthalmoscopy (AO-FIO) allows imaging of the cone photoreceptor in the living human retina. However, clinical interpretation of the AO-FIO image remains challenging due to suboptimal quality arising from residual uncorrected wavefront aberrations and rapid eye motion. An objective method of assessing image quality is necessary to determine whether an AO-FIO image is suitable for grading and diagnostic purpose. In this work, we explore the use of focus measure operators as a surrogate measure of AO-FIO image quality. A set of operators are tested on data sets acquired at different focal depths and different retinal locations from healthy volunteers. Our results demonstrate differences in focus measure operator performance in quantifying AO-FIO image quality. Further, we discuss the potential application of the selected focus operators in (i) selection of the best quality AO-FIO image from a series of images collected at the same retinal location and (ii) assessment of longitudinal changes in the diseased retina. Focus function could be incorporated into real-time AO-FIO image processing and provide an initial automated quality assessment during image acquisition or reading center grading. PMID:29552404
Gradient Magnitude Similarity Deviation: A Highly Efficient Perceptual Image Quality Index.
Xue, Wufeng; Zhang, Lei; Mou, Xuanqin; Bovik, Alan C
2014-02-01
It is an important task to faithfully evaluate the perceptual quality of output images in many applications, such as image compression, image restoration, and multimedia streaming. A good image quality assessment (IQA) model should not only deliver high quality prediction accuracy, but also be computationally efficient. The efficiency of IQA metrics is becoming particularly important due to the increasing proliferation of high-volume visual data in high-speed networks. We present a new effective and efficient IQA model, called gradient magnitude similarity deviation (GMSD). The image gradients are sensitive to image distortions, while different local structures in a distorted image suffer different degrees of degradations. This motivates us to explore the use of global variation of gradient based local quality map for overall image quality prediction. We find that the pixel-wise gradient magnitude similarity (GMS) between the reference and distorted images combined with a novel pooling strategy-the standard deviation of the GMS map-can predict accurately perceptual image quality. The resulting GMSD algorithm is much faster than most state-of-the-art IQA methods, and delivers highly competitive prediction accuracy. MATLAB source code of GMSD can be downloaded at http://www4.comp.polyu.edu.hk/~cslzhang/IQA/GMSD/GMSD.htm.
Alonso-Caneiro, David; Sampson, Danuta M; Chew, Avenell L; Collins, Michael J; Chen, Fred K
2018-02-01
Adaptive optics flood illumination ophthalmoscopy (AO-FIO) allows imaging of the cone photoreceptor in the living human retina. However, clinical interpretation of the AO-FIO image remains challenging due to suboptimal quality arising from residual uncorrected wavefront aberrations and rapid eye motion. An objective method of assessing image quality is necessary to determine whether an AO-FIO image is suitable for grading and diagnostic purpose. In this work, we explore the use of focus measure operators as a surrogate measure of AO-FIO image quality. A set of operators are tested on data sets acquired at different focal depths and different retinal locations from healthy volunteers. Our results demonstrate differences in focus measure operator performance in quantifying AO-FIO image quality. Further, we discuss the potential application of the selected focus operators in (i) selection of the best quality AO-FIO image from a series of images collected at the same retinal location and (ii) assessment of longitudinal changes in the diseased retina. Focus function could be incorporated into real-time AO-FIO image processing and provide an initial automated quality assessment during image acquisition or reading center grading.
Comprehensive model for predicting perceptual image quality of smart mobile devices.
Gong, Rui; Xu, Haisong; Luo, M R; Li, Haifeng
2015-01-01
An image quality model for smart mobile devices was proposed based on visual assessments of several image quality attributes. A series of psychophysical experiments were carried out on two kinds of smart mobile devices, i.e., smart phones and tablet computers, in which naturalness, colorfulness, brightness, contrast, sharpness, clearness, and overall image quality were visually evaluated under three lighting environments via categorical judgment method for various application types of test images. On the basis of Pearson correlation coefficients and factor analysis, the overall image quality could first be predicted by its two constituent attributes with multiple linear regression functions for different types of images, respectively, and then the mathematical expressions were built to link the constituent image quality attributes with the physical parameters of smart mobile devices and image appearance factors. The procedure and algorithms were applicable to various smart mobile devices, different lighting conditions, and multiple types of images, and performance was verified by the visual data.
[Quality of the Early Cervical Cancer Detection Program in the State of Nuevo León].
Salinas-Martínez, A M; Villarreal-Ríos, E; Garza-Elizondo, M E; Fraire-Gloria, J M; López-Franco, J J; Barboza-Quintana, O
1997-01-01
To determine the quality of the Early Cervical Cancer Detection Program in the state of Nuevo León. A random selection of 4791 cytologic reports were analyzed, emitted by the State Ministry of Health, the University Hospital and the Mexican Institute for Social Security early cervical cancer detection modules. Pap tests of women with hysterectomy, current pregnancy, menopause or positive result were excluded. Quality was measured with previously defined standards. Analysis included, besides univariate statistics, tests of significance for proportions and means. The quality of the program was fairly satisfactory at the level of the State. The quality of the sampling procedure was low; 39.9% of the tests contained endocervical cells. Quality of coverage was low; 15.6% were women 25+years with first time Pap test. Quality of opportunity was high; 8.5 +/- 7 weekdays between the date of the pap smear and the interpretation date. Strategies are needed to increase the impact of the state program, such as improving the sampling procedure and the coverage quality levels.
Image Quality Performance Measurement of the microPET Focus 120
NASA Astrophysics Data System (ADS)
Ballado, Fernando Trejo; López, Nayelli Ortega; Flores, Rafael Ojeda; Ávila-Rodríguez, Miguel A.
2010-12-01
The aim of this work is to evaluate the characteristics involved in the image reconstruction of the microPET Focus 120. For this evaluation were used two different phantoms; a miniature hot-rod Derenzo phantom and a National Electrical Manufacturers Association (NEMA) NU4-2008 image quality (IQ) phantom. The best image quality was obtained when using OSEM3D as the reconstruction method reaching a spatial resolution of 1.5 mm with the Derenzo phantom filled with 18F. Image quality test results indicate a superior image quality for the Focus 120 when compared to previous microPET models.
Behavior, neuropsychology and fMRI.
Bennett, Maxwell R; Hatton, Sean; Hermens, Daniel F; Lagopoulos, Jim
Cognitive neuroscientists in the late 20th century began the task of identifying the part(s) of the brain concerned with normal behavior as manifest in the psychological capacities as affective powers, reasoning, behaving purposively and the pursuit of goals, following introduction of the 'functional magnetic resonance imaging' (fMRI) method for identifying brain activity. For this research program to be successful two questions require satisfactory answers. First, as the fMRI method can currently only be used on stationary subjects, to what extent can neuropsychological tests applicable to such stationary subjects be correlated with normal behavior. Second, to what extent can correlations between the various neuropsychological tests on the one hand, and sites of brain activity determined with fMRI on the other, be regarded as established. The extent to which these questions have yet received satisfactory answers is reviewed, and suggestions made both for improving correlations of neuropsychological tests with behavior as well as with the results of fMRI-based observations. Copyright © 2016. Published by Elsevier Ltd.
PRELIMINARY STUDIES OF THE GASTROINTESTINAL TRACT WITH COLLOIDAL BARIUM
Windholz, Frank; Kaplan, Henry S.; Jones, Henry H.
1951-01-01
A stable colloidal suspension of barium sulfate has been developed and tested in roentgen examination of the gastrointestinal tract. The new material is rather distinctive in radiographic appearance and can usually be differentiated from simple barium-water mixtures by inspection of roentgenograms of the opacified stomach and small intestine. It usually affords a satisfactory demonstration of the mucosal folds of the stomach and duodenal bulb and is considerably more resistant to flocculation and precipitation by retained gastric secretions. In the small intestine, it has little tendency to undergo flocculation and fragmentation, and permits visualization of fine mucosal configurations with unusual clarity. Its motility is about the same as that of conventional suspensions. Air contrast colon examinations with the colloidal preparation exhibit a very uniform, opaque, and stable coating of the bowel wall and are more consistently satisfactory than when simple barium-water mixtures are used. ImagesFigure 1.Figure 1.Figure 1.Figure 1.Figure 2.Figure 2.Figure 3.Figure 4.Figure 4.Figure 5.Figure 5.Figure 6. PMID:14812347
Image quality assessment metric for frame accumulated image
NASA Astrophysics Data System (ADS)
Yu, Jianping; Li, Gang; Wang, Shaohui; Lin, Ling
2018-01-01
The medical image quality determines the accuracy of diagnosis, and the gray-scale resolution is an important parameter to measure image quality. But current objective metrics are not very suitable for assessing medical images obtained by frame accumulation technology. Little attention was paid to the gray-scale resolution, basically based on spatial resolution and limited to the 256 level gray scale of the existing display device. Thus, this paper proposes a metric, "mean signal-to-noise ratio" (MSNR) based on signal-to-noise in order to be more reasonable to evaluate frame accumulated medical image quality. We demonstrate its potential application through a series of images under a constant illumination signal. Here, the mean image of enough images was regarded as the reference image. Several groups of images by different frame accumulation and their MSNR were calculated. The results of the experiment show that, compared with other quality assessment methods, the metric is simpler, more effective, and more suitable for assessing frame accumulated images that surpass the gray scale and precision of the original image.
Synthesized view comparison method for no-reference 3D image quality assessment
NASA Astrophysics Data System (ADS)
Luo, Fangzhou; Lin, Chaoyi; Gu, Xiaodong; Ma, Xiaojun
2018-04-01
We develop a no-reference image quality assessment metric to evaluate the quality of synthesized view rendered from the Multi-view Video plus Depth (MVD) format. Our metric is named Synthesized View Comparison (SVC), which is designed for real-time quality monitoring at the receiver side in a 3D-TV system. The metric utilizes the virtual views in the middle which are warped from left and right views by Depth-image-based rendering algorithm (DIBR), and compares the difference between the virtual views rendered from different cameras by Structural SIMilarity (SSIM), a popular 2D full-reference image quality assessment metric. The experimental results indicate that our no-reference quality assessment metric for the synthesized images has competitive prediction performance compared with some classic full-reference image quality assessment metrics.
Deep supervised dictionary learning for no-reference image quality assessment
NASA Astrophysics Data System (ADS)
Huang, Yuge; Liu, Xuesong; Tian, Xiang; Zhou, Fan; Chen, Yaowu; Jiang, Rongxin
2018-03-01
We propose a deep convolutional neural network (CNN) for general no-reference image quality assessment (NR-IQA), i.e., accurate prediction of image quality without a reference image. The proposed model consists of three components such as a local feature extractor that is a fully CNN, an encoding module with an inherent dictionary that aggregates local features to output a fixed-length global quality-aware image representation, and a regression module that maps the representation to an image quality score. Our model can be trained in an end-to-end manner, and all of the parameters, including the weights of the convolutional layers, the dictionary, and the regression weights, are simultaneously learned from the loss function. In addition, the model can predict quality scores for input images of arbitrary sizes in a single step. We tested our method on commonly used image quality databases and showed that its performance is comparable with that of state-of-the-art general-purpose NR-IQA algorithms.
An Underwater Color Image Quality Evaluation Metric.
Yang, Miao; Sowmya, Arcot
2015-12-01
Quality evaluation of underwater images is a key goal of underwater video image retrieval and intelligent processing. To date, no metric has been proposed for underwater color image quality evaluation (UCIQE). The special absorption and scattering characteristics of the water medium do not allow direct application of natural color image quality metrics especially to different underwater environments. In this paper, subjective testing for underwater image quality has been organized. The statistical distribution of the underwater image pixels in the CIELab color space related to subjective evaluation indicates the sharpness and colorful factors correlate well with subjective image quality perception. Based on these, a new UCIQE metric, which is a linear combination of chroma, saturation, and contrast, is proposed to quantify the non-uniform color cast, blurring, and low-contrast that characterize underwater engineering and monitoring images. Experiments are conducted to illustrate the performance of the proposed UCIQE metric and its capability to measure the underwater image enhancement results. They show that the proposed metric has comparable performance to the leading natural color image quality metrics and the underwater grayscale image quality metrics available in the literature, and can predict with higher accuracy the relative amount of degradation with similar image content in underwater environments. Importantly, UCIQE is a simple and fast solution for real-time underwater video processing. The effectiveness of the presented measure is also demonstrated by subjective evaluation. The results show better correlation between the UCIQE and the subjective mean opinion score.
Learning to rank for blind image quality assessment.
Gao, Fei; Tao, Dacheng; Gao, Xinbo; Li, Xuelong
2015-10-01
Blind image quality assessment (BIQA) aims to predict perceptual image quality scores without access to reference images. State-of-the-art BIQA methods typically require subjects to score a large number of images to train a robust model. However, subjective quality scores are imprecise, biased, and inconsistent, and it is challenging to obtain a large-scale database, or to extend existing databases, because of the inconvenience of collecting images, training the subjects, conducting subjective experiments, and realigning human quality evaluations. To combat these limitations, this paper explores and exploits preference image pairs (PIPs) such as the quality of image Ia is better than that of image Ib for training a robust BIQA model. The preference label, representing the relative quality of two images, is generally precise and consistent, and is not sensitive to image content, distortion type, or subject identity; such PIPs can be generated at a very low cost. The proposed BIQA method is one of learning to rank. We first formulate the problem of learning the mapping from the image features to the preference label as one of classification. In particular, we investigate the utilization of a multiple kernel learning algorithm based on group lasso to provide a solution. A simple but effective strategy to estimate perceptual image quality scores is then presented. Experiments show that the proposed BIQA method is highly effective and achieves a performance comparable with that of state-of-the-art BIQA algorithms. Moreover, the proposed method can be easily extended to new distortion categories.
Standardizing Quality Assessment of Fused Remotely Sensed Images
NASA Astrophysics Data System (ADS)
Pohl, C.; Moellmann, J.; Fries, K.
2017-09-01
The multitude of available operational remote sensing satellites led to the development of many image fusion techniques to provide high spatial, spectral and temporal resolution images. The comparison of different techniques is necessary to obtain an optimized image for the different applications of remote sensing. There are two approaches in assessing image quality: 1. Quantitatively by visual interpretation and 2. Quantitatively using image quality indices. However an objective comparison is difficult due to the fact that a visual assessment is always subject and a quantitative assessment is done by different criteria. Depending on the criteria and indices the result varies. Therefore it is necessary to standardize both processes (qualitative and quantitative assessment) in order to allow an objective image fusion quality evaluation. Various studies have been conducted at the University of Osnabrueck (UOS) to establish a standardized process to objectively compare fused image quality. First established image fusion quality assessment protocols, i.e. Quality with No Reference (QNR) and Khan's protocol, were compared on varies fusion experiments. Second the process of visual quality assessment was structured and standardized with the aim to provide an evaluation protocol. This manuscript reports on the results of the comparison and provides recommendations for future research.
Bayesian framework inspired no-reference region-of-interest quality measure for brain MRI images
Osadebey, Michael; Pedersen, Marius; Arnold, Douglas; Wendel-Mitoraj, Katrina
2017-01-01
Abstract. We describe a postacquisition, attribute-based quality assessment method for brain magnetic resonance imaging (MRI) images. It is based on the application of Bayes theory to the relationship between entropy and image quality attributes. The entropy feature image of a slice is segmented into low- and high-entropy regions. For each entropy region, there are three separate observations of contrast, standard deviation, and sharpness quality attributes. A quality index for a quality attribute is the posterior probability of an entropy region given any corresponding region in a feature image where quality attribute is observed. Prior belief in each entropy region is determined from normalized total clique potential (TCP) energy of the slice. For TCP below the predefined threshold, the prior probability for a region is determined by deviation of its percentage composition in the slice from a standard normal distribution built from 250 MRI volume data provided by Alzheimer’s Disease Neuroimaging Initiative. For TCP above the threshold, the prior is computed using a mathematical model that describes the TCP–noise level relationship in brain MRI images. Our proposed method assesses the image quality of each entropy region and the global image. Experimental results demonstrate good correlation with subjective opinions of radiologists for different types and levels of quality distortions. PMID:28630885
Suh, Young Joo; Kim, Young Jin; Kim, Jin Young; Chang, Suyon; Im, Dong Jin; Hong, Yoo Jin; Choi, Byoung Wook
2017-11-01
We aimed to determine the effect of a whole-heart motion-correction algorithm (new-generation snapshot freeze, NG SSF) on the image quality of cardiac computed tomography (CT) images in patients with mechanical valve prostheses compared to standard images without motion correction and to compare the diagnostic accuracy of NG SSF and standard CT image sets for the detection of prosthetic valve abnormalities. A total of 20 patients with 32 mechanical valves who underwent wide-coverage detector cardiac CT with single-heartbeat acquisition were included. The CT image quality for subvalvular (below the prosthesis) and valvular regions (valve leaflets) of mechanical valves was assessed by two observers on a four-point scale (1 = poor, 2 = fair, 3 = good, and 4 = excellent). Paired t-tests or Wilcoxon signed rank tests were used to compare image quality scores and the number of diagnostic phases (image quality score≥3) between the standard image sets and NG SSF image sets. Diagnostic performance for detection of prosthetic valve abnormalities was compared between two image sets with the final diagnosis set by re-operation or clinical findings as the standard reference. NG SSF image sets had better image quality scores than standard image sets for both valvular and subvalvular regions (P < 0.05 for both). The number of phases that were of diagnostic image quality per patient was significantly greater in the NG SSF image set than standard image set for both valvular and subvalvular regions (P < 0.0001). Diagnostic performance of NG SSF image sets for the detection of prosthetic abnormalities (20 pannus and two paravalvular leaks) was greater than that of standard image sets (P < 0.05). Application of NG SSF can improve CT image quality and diagnostic accuracy in patients with mechanical valves compared to standard images. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
Digital mammography--DQE versus optimized image quality in clinical environment: an on site study
NASA Astrophysics Data System (ADS)
Oberhofer, Nadia; Fracchetti, Alessandro; Springeth, Margareth; Moroder, Ehrenfried
2010-04-01
The intrinsic quality of the detection system of 7 different digital mammography units (5 direct radiography DR; 2 computed radiography CR), expressed by DQE, has been compared with their image quality/dose performances in clinical use. DQE measurements followed IEC 62220-1-2 using a tungsten test object for MTF determination. For image quality assessment two different methods have been applied: 1) measurement of contrast to noise ratio (CNR) according to the European guidelines and 2) contrast-detail (CD) evaluation. The latter was carried out with the phantom CDMAM ver. 3.4 and the commercial software CDMAM Analyser ver. 1.1 (both Artinis) for automated image analysis. The overall image quality index IQFinv proposed by the software has been validated. Correspondence between the two methods has been shown figuring out a linear correlation between CNR and IQFinv. All systems were optimized with respect to image quality and average glandular dose (AGD) within the constraints of automatic exposure control (AEC). For each equipment, a good image quality level was defined by means of CD analysis, and the corresponding CNR value considered as target value. The goal was to achieve for different PMMA-phantom thicknesses constant image quality, that means the CNR target value, at minimum dose. All DR systems exhibited higher DQE and significantly better image quality compared to CR systems. Generally switching, where available, to a target/filter combination with an x-ray spectrum of higher mean energy permitted dose savings at equal image quality. However, several systems did not allow to modify the AEC in order to apply optimal radiographic technique in clinical use. The best ratio image quality/dose was achieved by a unit with a-Se detector and W anode only recently available on the market.
Drees, R.; Forrest, L. J.; Chappell, R.
2009-01-01
Objectives Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Methods Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Results Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. Clinical Significance We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity. PMID:19508490
Image quality classification for DR screening using deep learning.
FengLi Yu; Jing Sun; Annan Li; Jun Cheng; Cheng Wan; Jiang Liu
2017-07-01
The quality of input images significantly affects the outcome of automated diabetic retinopathy (DR) screening systems. Unlike the previous methods that only consider simple low-level features such as hand-crafted geometric and structural features, in this paper we propose a novel method for retinal image quality classification (IQC) that performs computational algorithms imitating the working of the human visual system. The proposed algorithm combines unsupervised features from saliency map and supervised features coming from convolutional neural networks (CNN), which are fed to an SVM to automatically detect high quality vs poor quality retinal fundus images. We demonstrate the superior performance of our proposed algorithm on a large retinal fundus image dataset and the method could achieve higher accuracy than other methods. Although retinal images are used in this study, the methodology is applicable to the image quality assessment and enhancement of other types of medical images.
Tod, D; Edwards, C
2015-09-01
The purpose of this study was to examine relationships among bodybuilding dependence, muscle satisfaction, body image-related quality of life and body image-related coping strategies, and test the hypothesis that muscle dysmorphia characteristics may predict quality of life via coping strategies. Participants (294 males, Mage=20.5 years, SD=3.1) participated in a cross-sectional survey. Participants completed questionnaires assessing muscle satisfaction, bodybuilding dependence, body image-related quality of life and body image-related coping. Quality of life was correlated positively with muscle satisfaction and bodybuilding dependence but negatively with body image coping (P<0.05). Body image coping was correlated positively with bodybuilding dependence and negatively with muscle satisfaction (P<0.05). Mediation analysis found that bodybuilding dependence and muscle satisfaction predicted quality of life both directly and indirectly via body image coping strategies (as evidenced by the bias corrected and accelerated bootstrapped confidence intervals). These results provide preliminary evidence regarding the ways that muscularity concerns might influence body image-related quality of life. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Antiscatter grid use in pediatric digital tomosynthesis imaging†
King, Jenna M.; Reed, Martin
2011-01-01
The objective of this study was to assess the effect of antiscatter grid use on tomosynthesis image quality. We performed an observer study that rated the image quality of digital tomosynthesis scout radiographs and slice images of a Leeds TO.20 contrast‐detail test object embedded in acrylic with and without a grid. We considered 10, 15, 20 and 25 cm of acrylic to represent the wide range of patient thicknesses encountered in pediatric imaging. We also acquired and rated images without a grid at an increased patient dose. The readers counted the total number of visible details in each image as a measure of relative image quality. We observed that the antiscatter grid improves tomosynthesis image quality compared to the grid‐out case, which received image quality scores similar to grid‐in radiography. Our results suggest that, in order to achieve the best image quality in exchange for the increase in patient dose, it may often be appropriate to include an antiscatter grid for pediatric tomosynthesis imaging, particularly if the patient thickness is greater than 10 cm. PACS number: 87.57.‐s PMID:22089021
Enhancement of digital radiography image quality using a convolutional neural network.
Sun, Yuewen; Li, Litao; Cong, Peng; Wang, Zhentao; Guo, Xiaojing
2017-01-01
Digital radiography system is widely used for noninvasive security check and medical imaging examination. However, the system has a limitation of lower image quality in spatial resolution and signal to noise ratio. In this study, we explored whether the image quality acquired by the digital radiography system can be improved with a modified convolutional neural network to generate high-resolution images with reduced noise from the original low-quality images. The experiment evaluated on a test dataset, which contains 5 X-ray images, showed that the proposed method outperformed the traditional methods (i.e., bicubic interpolation and 3D block-matching approach) as measured by peak signal to noise ratio (PSNR) about 1.3 dB while kept highly efficient processing time within one second. Experimental results demonstrated that a residual to residual (RTR) convolutional neural network remarkably improved the image quality of object structural details by increasing the image resolution and reducing image noise. Thus, this study indicated that applying this RTR convolutional neural network system was useful to improve image quality acquired by the digital radiography system.
Hoscheit, Larry P; Heng, Hock Gan; Lim, Chee Kin; Weng, Hsin-Yi
2018-05-01
Image quality in B-mode ultrasound is important as it reflects the diagnostic accuracy and diagnostic information provided during clinical scanning. Quality assurance programs for B-mode ultrasound systems/components are comprised of initial quality acceptance testing and subsequent regularly scheduled quality control testing. The importance of quality assurance programs for B-mode ultrasound image quality using ultrasound phantoms is well documented in the human medical and medical physics literature. The purpose of this prospective, cross-sectional, survey study was to determine the prevalence and methodology of quality acceptance testing and quality control testing of image quality for ultrasound system/components among veterinary sonographers. An online electronic survey was sent to 1497 members of veterinary imaging organizations: the American College of Veterinary Radiology, the Veterinary Ultrasound Society, and the European Association of Veterinary Diagnostic Imaging, and a total of 167 responses were received. The results showed that the percentages of veterinary sonographers performing quality acceptance testing and quality control testing are 42% (64/151; 95% confidence interval 34-52%) and 26% (40/156: 95% confidence interval 19-33%) respectively. Of the respondents who claimed to have quality acceptance testing or quality control testing of image quality in place for their ultrasound system/components, 0% have performed quality acceptance testing or quality control testing correctly (quality acceptance testing 95% confidence interval: 0-6%, quality control testing 95% confidence interval: 0-11%). Further education and guidelines are recommended for veterinary sonographers in the area of quality acceptance testing and quality control testing for B-mode ultrasound equipment/components. © 2018 American College of Veterinary Radiology.
Walch, Katharina; Kowarik, Eleen; Leithner, Katharina; Schätz, Theresa; Dörfler, Daniela; Wenzl, René
2011-08-01
To evaluate the long-term outcomes and degree of satisfaction after neovaginoplasty according to Wharton-Sheares-George in women with Mayer-Rokitansky-Küster-Hauser syndrome. Open, monocentric follow-up study. University hospital and referral center for pediatric and adolescent gynecology. Ten patients with Mayer-Rokitansky-Küster-Hauser syndrome with neovaginas created according to Wharton-Sheares-George 3 to 77 months ago. Gynecologic follow-up examination, including vaginal swab, bacterial culture, Papanicolaou smear, hybrid capture test for human papillomavirus typing, biopsy, pelvic ultrasound, and 2 questionnaires concerning global quality of life and degree of sexual satisfaction. Satisfaction with sexual function, quality of life, length and width of neovagina, structure of vaginal epithelium, and type of bacterial colonization. Functional long-term follow-up results showed a high subjective degree of general well-being and sexual satisfaction in affected women. A satisfactory neovaginal length (mean, 8.3 ± 1.06 cm; range, 7-10 cm) and width (mean, 3.3 ± 0.5 cm; range, 2.5-4 cm) was obtained. As revealed by smears and biopsy, the neovagina resembled a natural vagina with regard to type of bacterial colonization and structure of epithelium. The goal of any method of creating a neovagina is to provide the patient the possibility to have satisfactory sexual intercourse and to enhance well-being and quality of life. These aims can be achieved by creating a neovagina according to Wharton-Sheares-George. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Janik, Michał Robert; Rogula, Tomasz; Bielecka, Ilona; Kwiatkowski, Andrzej; Paśnik, Krzysztof
2016-12-01
The aims of our study were to compare quality of life (QOL) in obese patients after bariatric surgery with that in controls seeking surgery and to investigate which factors are associated with QOL in the Moorehead-Ardelt Quality of Life Questionnaire II (MA II). This was a cross-sectional study. The operated group consisted of patients after laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass. The MA II was administered by e-mail to 305 patients 12-18 months after surgery. The control groups consisted of 101 obese patients. We compared the QOL scores and considered good and very good outcomes to be satisfactory. Multiple logistic regression and correlation analysis was performed to identify factors associated with QOL. In the operated group, the total MA II score was 1.70 ± 0.76, which was higher than 0.59 ± 1.17 in the control group. The score adjusted for the type of surgery was comparable. The prevalence of satisfactory QOL outcomes was similar in both post-operative subgroups and was still higher than in the control group. We identified four factors associated with higher QOL in obese patients. Weight loss was not correlated with total score in MAII. This study demonstrates that patients after bariatric surgery have a higher score in MA II, which reflects better QOL. The scoring adjusted by type of operation is comparable. QOL among obese patients is dependent on age, gender, history of bariatric surgery, and partnered status. Body mass reduction was not associated with outcome in MAII.
Bulk Shielding Facility quarterly report, April, May and June 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Corbett, B.L.; Lance, E.D.
1984-12-01
The BSR operated at an average power level of 1310 kW for 3.8% of the time during April, May, and June. Water-quality control in both the reactor primary and secondary cooling systems was satisfactory. The PCA was used in training startups and was operated on five occasions for the NBS and HEDL recheck of a previous experiment run on the LWR pressure vessel surveillance dosimetry improvement program.
1982-11-01
model but uses the Hilbert transform to model intermittency as well as Gaussian structure patchiness. Includes University of Washington model features...Requirements for Satisfactory Elevator Control Characteristics, NACA TN 1060, June 1946. 852 - - - - 137. Jones, R. T., and H. Greenberg , Effect of Hinge...Moment Parameters on Elevator Stick Forces in Rapid Maneuvers NACA Report 798, Nov. 1944. 138. Greenberg , H., and L. Sternfield, A Theoretical
[Results of urethral reconstruction in adults after multiple hypospadias repairs].
Gamidov, S I; Shneiderman, M G; Pushkar, D Yu; Vasil'ev, A O; Govorov, A V; Ovchinnikov, R I; Popova, A Yu; Dusmukhamedov, R D
2017-06-01
To improve treatment results in patients after multiple hypospadias repairs by optimizing the postoperative management. Eighty-two patients (mean age 48.1+/-15.3 years) with urethral strictures secondary to failed hypospadias repairs underwent staged graft urethroplasty using oral mucosa (cheek, lip, tongue) as a grafting material. In 62 patients, at the end of surgery the bladder was drained with a standard Foley catheter. In twenty patients the bladder was drained with a modified silicone urethral catheter, which had an additional channel for delivering drugs and removing the urethral wound effluent, and a second additional channel for inflating a balloon fixed to the catheter tube at different parts of the catheter. The mean length of the stricture was 5.4+/-1.2 cm (from 1 to 16 cm). Twenty-eight patients had postoperative complications. Using the modified catheter resulted in statistically significantly (p<0.05) smaller percentage of complications (10% vs 41.9%) compared to standard Foley catheter. Urinalysis and sperm test on the follow up examination at 12 months showed that only 9 (10.9%) patients had signs of the inflammatory process. Seventy-five patients (91.5%) rated the appearance of the penis as "good"; only 5 (6.1%) and 2 (2.4%) patients considered the result as "satisfactory" and "unsatisfactory", respectively. Eighty patient (97.6%) regarded the treatment result as "good" for the quality of urination and only two (2.4%) considered it "satisfactory". When assessing the strength of urinary stream, 64 (78.1%), 13 (15.8%) and 5 (6.1%) patients rated it as "good", "satisfactory", and "unsatisfactory", respectively. The study findings shows that staged urethroplasty using the oral mucosa restores the urethral patency, reduces the severity of the inflammatory process, thus improving the quality of life of patients after failed hypospadias repair. The proposed modification of the catheter ensures the timely delivery of drugs to the surgical site, evacuation the wound effluent from the urethra and helps prevent strictures by periodically inflating the adjustable balloon-dilator.
Transplant Nurses' Work Environment: A Cross-Sectional Multi-Center Study.
Kugler, Christiane; Akca, Selda; Einhorn, Ina; Rebafka, Anne; Russell, Cynthia L
2016-09-01
BACKGROUND Numerically, nurses represent the largest healthcare profession, thus setting norms for the quality and safety of direct patient care. Evidence of a global shortage of nurses in all clinical practice settings across different healthcare systems and countries has been documented. The aims of the present study were: (1) to assess work environments in a sample of German transplant nurses, and (2) to compare their statements with a US-based sample. MATERIAL AND METHODS In a cross-sectional study, 181 transplant nurses from 16 German transplant centers provided information on their work environments. The translated version of the Job Design (JD) and Job Satisfaction (JS) survey showed satisfactory internal consistency for the JD (0.78) and JS (0.93) subscales. German nurses' work environments were compared with 331 transplant nurses from the US. RESULTS The majority of transplant nurses were female (81.8%), 55.4% were age 21-40 years, and 78.1% were employed full-time. German (versus US) transplant nurses reported their job design to be best for 'skill varieties' (p≤0.0002), and worst for 'autonomy' (p≤0.01). Job satisfaction was best with 'opportunities for autonomy and growth' (p≤0.0001), and 'pay and benefits' (p≤0.0001) was lowest. A higher professional degree (OR 1.57; p≤0.03; 95% CI 1.19-2.86), and longer time in transplant (OR 1.24; p≤0.001; 95% CI 1.11-1.38) showed a positive impact on German transplant nurses' perceptions of 'job satisfaction'. Nurses with time-dependent working contracts perceived more stress negatively affecting job satisfaction (OR 1.13; p≤0.009; 95% CI 1.02-12.82). CONCLUSIONS German specialty nurses working in the field of solid organ transplantation rate their work environments with respect to job design and job satisfaction as satisfactory. Institutions' investment into satisfactory nurse work environments and specializing nurses might increase the quality of care, thus improving patient outcomes.
Teich, Sorin; Al-Rawi, Wisam; Heima, Masahiro; Faddoul, Fady F; Goldzweig, Gil; Gutmacher, Zvi; Aizenbud, Dror
2016-10-01
To evaluate the image quality generated by eight commercially available intraoral sensors. Eighteen clinicians ranked the quality of a bitewing acquired from one subject using eight different intraoral sensors. Analytical methods used to evaluate clinical image quality included the Visual Grading Characteristics method, which helps to quantify subjective opinions to make them suitable for analysis. The Dexis sensor was ranked significantly better than Sirona and Carestream-Kodak sensors; and the image captured using the Carestream-Kodak sensor was ranked significantly worse than those captured using Dexis, Schick and Cyber Medical Imaging sensors. The Image Works sensor image was rated the lowest by all clinicians. Other comparisons resulted in non-significant results. None of the sensors was considered to generate images of significantly better quality than the other sensors tested. Further research should be directed towards determining the clinical significance of the differences in image quality reported in this study. © 2016 FDI World Dental Federation.
Ginieri-Coccossis, M; Triantafillou, E; Tomaras, V; Soldatos, C; Mavreas, V; Christodoulou, G
2012-01-01
Τhe present study examines main psychometric properties of the World Health Organisation (WHO) quality of life (QoL) instrument, the WHOQOL-BREF with the inclusion of four national items. Participants were 425 adult native Greek speaking, grouped into patients with physical disorders, psychiatric disorders and healthy individuals. Participants were administered WHOQOL-BREF and 23 national items, the General Health Questionnaire (GHQ-28) and the Life Satisfaction Index (LSI). Confirmatory factor analysis produced acceptable fit values for the original model of 26 items within the four WHOQOL domains: physical health, psychological health, social relationships and environment. Testing for the fit of national items within this model, the results indicated four new items with the most satisfactory fit indices and were thus included forming a 30-items version. The national items refer to: (a) nutrition, (b) satisfaction with work (both loaded in the physical health domain), (c) home life and (d) social life (both loaded in the social relationships domain). Statistical tests were applied to the 26- and 30-items versions producing satisfactory results, with the 30-items version showing slightly better values. Furthermore, results on the 30-items version included: (a) internal consistency, which was found satisfactory, with alpha values ranging from α=0.67-0.81, while the inclusion of new items produced higher alpha values in physical health and social relationships domains, (b) construct validity with good item-domain correlations, as well as strong correlations between domain scores, (c) convergent validity, which was very satisfactory, showing good correlations with GHQ-28 and LSI, (d) discriminant validity, showing instrument's ability to detect QoL differences between healthy and unhealthy participants, and between physically ill and psychiatric patients, and (e) test-retest reliability, with ICC scores in excess of 0.80 obtaining for all domains. The WHOQOL-BREF Greek version was found to perform well with sick and healthy participants, demonstrating satisfactory psychometric properties. Use of the instrument may be recommended for clinical and general populations, for service or intervention evaluation, as well as for cross-cultural clinical trials.
Feature-Motivated Simplified Adaptive PCNN-Based Medical Image Fusion Algorithm in NSST Domain.
Ganasala, Padma; Kumar, Vinod
2016-02-01
Multimodality medical image fusion plays a vital role in diagnosis, treatment planning, and follow-up studies of various diseases. It provides a composite image containing critical information of source images required for better localization and definition of different organs and lesions. In the state-of-the-art image fusion methods based on nonsubsampled shearlet transform (NSST) and pulse-coupled neural network (PCNN), authors have used normalized coefficient value to motivate the PCNN-processing both low-frequency (LF) and high-frequency (HF) sub-bands. This makes the fused image blurred and decreases its contrast. The main objective of this work is to design an image fusion method that gives the fused image with better contrast, more detail information, and suitable for clinical use. We propose a novel image fusion method utilizing feature-motivated adaptive PCNN in NSST domain for fusion of anatomical images. The basic PCNN model is simplified, and adaptive-linking strength is used. Different features are used to motivate the PCNN-processing LF and HF sub-bands. The proposed method is extended for fusion of functional image with an anatomical image in improved nonlinear intensity hue and saturation (INIHS) color model. Extensive fusion experiments have been performed on CT-MRI and SPECT-MRI datasets. Visual and quantitative analysis of experimental results proved that the proposed method provides satisfactory fusion outcome compared to other image fusion methods.
PyDBS: an automated image processing workflow for deep brain stimulation surgery.
D'Albis, Tiziano; Haegelen, Claire; Essert, Caroline; Fernández-Vidal, Sara; Lalys, Florent; Jannin, Pierre
2015-02-01
Deep brain stimulation (DBS) is a surgical procedure for treating motor-related neurological disorders. DBS clinical efficacy hinges on precise surgical planning and accurate electrode placement, which in turn call upon several image processing and visualization tasks, such as image registration, image segmentation, image fusion, and 3D visualization. These tasks are often performed by a heterogeneous set of software tools, which adopt differing formats and geometrical conventions and require patient-specific parameterization or interactive tuning. To overcome these issues, we introduce in this article PyDBS, a fully integrated and automated image processing workflow for DBS surgery. PyDBS consists of three image processing pipelines and three visualization modules assisting clinicians through the entire DBS surgical workflow, from the preoperative planning of electrode trajectories to the postoperative assessment of electrode placement. The system's robustness, speed, and accuracy were assessed by means of a retrospective validation, based on 92 clinical cases. The complete PyDBS workflow achieved satisfactory results in 92 % of tested cases, with a median processing time of 28 min per patient. The results obtained are compatible with the adoption of PyDBS in clinical practice.
Sandino, Juan; Wooler, Adam; Gonzalez, Felipe
2017-09-24
The increased technological developments in Unmanned Aerial Vehicles (UAVs) combined with artificial intelligence and Machine Learning (ML) approaches have opened the possibility of remote sensing of extensive areas of arid lands. In this paper, a novel approach towards the detection of termite mounds with the use of a UAV, hyperspectral imagery, ML and digital image processing is intended. A new pipeline process is proposed to detect termite mounds automatically and to reduce, consequently, detection times. For the classification stage, several ML classification algorithms' outcomes were studied, selecting support vector machines as the best approach for their role in image classification of pre-existing termite mounds. Various test conditions were applied to the proposed algorithm, obtaining an overall accuracy of 68%. Images with satisfactory mound detection proved that the method is "resolution-dependent". These mounds were detected regardless of their rotation and position in the aerial image. However, image distortion reduced the number of detected mounds due to the inclusion of a shape analysis method in the object detection phase, and image resolution is still determinant to obtain accurate results. Hyperspectral imagery demonstrated better capabilities to classify a huge set of materials than implementing traditional segmentation methods on RGB images only.
Blind CT image quality assessment via deep learning strategy: initial study
NASA Astrophysics Data System (ADS)
Li, Sui; He, Ji; Wang, Yongbo; Liao, Yuting; Zeng, Dong; Bian, Zhaoying; Ma, Jianhua
2018-03-01
Computed Tomography (CT) is one of the most important medical imaging modality. CT images can be used to assist in the detection and diagnosis of lesions and to facilitate follow-up treatment. However, CT images are vulnerable to noise. Actually, there are two major source intrinsically causing the CT data noise, i.e., the X-ray photo statistics and the electronic noise background. Therefore, it is necessary to doing image quality assessment (IQA) in CT imaging before diagnosis and treatment. Most of existing CT images IQA methods are based on human observer study. However, these methods are impractical in clinical for their complex and time-consuming. In this paper, we presented a blind CT image quality assessment via deep learning strategy. A database of 1500 CT images is constructed, containing 300 high-quality images and 1200 corresponding noisy images. Specifically, the high-quality images were used to simulate the corresponding noisy images at four different doses. Then, the images are scored by the experienced radiologists by the following attributes: image noise, artifacts, edge and structure, overall image quality, and tumor size and boundary estimation with five-point scale. We trained a network for learning the non-liner map from CT images to subjective evaluation scores. Then, we load the pre-trained model to yield predicted score from the test image. To demonstrate the performance of the deep learning network in IQA, correlation coefficients: Pearson Linear Correlation Coefficient (PLCC) and Spearman Rank Order Correlation Coefficient (SROCC) are utilized. And the experimental result demonstrate that the presented deep learning based IQA strategy can be used in the CT image quality assessment.
The use of the general image quality equation in the design and evaluation of imaging systems
NASA Astrophysics Data System (ADS)
Cota, Steve A.; Florio, Christopher J.; Duvall, David J.; Leon, Michael A.
2009-08-01
The design of any modern imaging system is the end result of many trade studies, each seeking to optimize image quality within real world constraints such as cost, schedule and overall risk. The National Imagery Interpretability Rating Scale (NIIRS) is a useful measure of image quality, because, by characterizing the overall interpretability of an image, it combines into one metric those contributors to image quality to which a human interpreter is most sensitive. The main drawback to using a NIIRS rating as a measure of image quality in engineering trade studies is the fact that it is tied to the human observer and cannot be predicted from physical principles and engineering parameters alone. The General Image Quality Equation (GIQE) of Leachtenauer et al. 1997 [Appl. Opt. 36, 8322-8328 (1997)] is a regression of actual image analyst NIIRS ratings vs. readily calculable engineering metrics, and provides a mechanism for using the expected NIIRS rating of an imaging system in the design and evaluation process. In this paper, we will discuss how we use the GIQE in conjunction with The Aerospace Corporation's Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) to evaluate imager designs, taking a hypothetical high resolution commercial imaging system as an example.
Uji, Akihito; Ooto, Sotaro; Hangai, Masanori; Arichika, Shigeta; Yoshimura, Nagahisa
2013-01-01
Purpose To investigate the effect of B-spline-based elastic image registration on adaptive optics scanning laser ophthalmoscopy (AO-SLO)-assisted capillary visualization. Methods AO-SLO videos were acquired from parafoveal areas in the eyes of healthy subjects and patients with various diseases. After nonlinear image registration, the image quality of capillary images constructed from AO-SLO videos using motion contrast enhancement was compared before and after B-spline-based elastic (nonlinear) image registration performed using ImageJ. For objective comparison of image quality, contrast-to-noise ratios (CNRS) for vessel images were calculated. For subjective comparison, experienced ophthalmologists ranked images on a 5-point scale. Results All AO-SLO videos were successfully stabilized by elastic image registration. CNR was significantly higher in capillary images stabilized by elastic image registration than in those stabilized without registration. The average ratio of CNR in images with elastic image registration to CNR in images without elastic image registration was 2.10 ± 1.73, with no significant difference in the ratio between patients and healthy subjects. Improvement of image quality was also supported by expert comparison. Conclusions Use of B-spline-based elastic image registration in AO-SLO-assisted capillary visualization was effective for enhancing image quality both objectively and subjectively. PMID:24265796
Learning a No-Reference Quality Assessment Model of Enhanced Images With Big Data.
Gu, Ke; Tao, Dacheng; Qiao, Jun-Fei; Lin, Weisi
2018-04-01
In this paper, we investigate into the problem of image quality assessment (IQA) and enhancement via machine learning. This issue has long attracted a wide range of attention in computational intelligence and image processing communities, since, for many practical applications, e.g., object detection and recognition, raw images are usually needed to be appropriately enhanced to raise the visual quality (e.g., visibility and contrast). In fact, proper enhancement can noticeably improve the quality of input images, even better than originally captured images, which are generally thought to be of the best quality. In this paper, we present two most important contributions. The first contribution is to develop a new no-reference (NR) IQA model. Given an image, our quality measure first extracts 17 features through analysis of contrast, sharpness, brightness and more, and then yields a measure of visual quality using a regression module, which is learned with big-data training samples that are much bigger than the size of relevant image data sets. The results of experiments on nine data sets validate the superiority and efficiency of our blind metric compared with typical state-of-the-art full-reference, reduced-reference and NA IQA methods. The second contribution is that a robust image enhancement framework is established based on quality optimization. For an input image, by the guidance of the proposed NR-IQA measure, we conduct histogram modification to successively rectify image brightness and contrast to a proper level. Thorough tests demonstrate that our framework can well enhance natural images, low-contrast images, low-light images, and dehazed images. The source code will be released at https://sites.google.com/site/guke198701/publications.
Cho, Yu Kyung
2016-07-01
In Korea, gastric cancer screening, either esophagogastroduodenoscopy or upper gastrointestinal series (UGIS), is performed biennially for adults aged 40 years or older. Screening endoscopy has been shown to be associated with localized cancer detection and better than UGIS. However, the diagnostic sensitivity of detecting cancer is not satisfactory. The National Endoscopy Quality Improvement (QI) program was initiated in 2009 to enhance the quality of medical institutions and improve the effectiveness of the National Cancer Screening Program (NCSP). The Korean Society of Gastrointestinal Endoscopy developed quality standards through a broad systematic review of other endoscopic quality guidelines and discussions with experts. The standards comprise five domains: qualifications of endoscopists, endoscopic unit facilities and equipment, endoscopic procedure, endoscopy outcomes, and endoscopic reprocessing. After 5 years of the QI program, feedback surveys showed that the perception of QI and endoscopic practice improved substantially in all domains of quality, but the quality standards need to be revised. How to avoid missing cancer in endoscopic procedures in daily practice was reviewed, which can be applied to the mass screening endoscopy. To improve the quality and effectiveness of NCSP, key performance indicators, acceptable quality standards, regular audit, and appropriate reimbursement are necessary.
Information retrieval based on single-pixel optical imaging with quick-response code
NASA Astrophysics Data System (ADS)
Xiao, Yin; Chen, Wen
2018-04-01
Quick-response (QR) code technique is combined with ghost imaging (GI) to recover original information with high quality. An image is first transformed into a QR code. Then the QR code is treated as an input image in the input plane of a ghost imaging setup. After measurements, traditional correlation algorithm of ghost imaging is utilized to reconstruct an image (QR code form) with low quality. With this low-quality image as an initial guess, a Gerchberg-Saxton-like algorithm is used to improve its contrast, which is actually a post processing. Taking advantage of high error correction capability of QR code, original information can be recovered with high quality. Compared to the previous method, our method can obtain a high-quality image with comparatively fewer measurements, which means that the time-consuming postprocessing procedure can be avoided to some extent. In addition, for conventional ghost imaging, the larger the image size is, the more measurements are needed. However, for our method, images with different sizes can be converted into QR code with the same small size by using a QR generator. Hence, for the larger-size images, the time required to recover original information with high quality will be dramatically reduced. Our method makes it easy to recover a color image in a ghost imaging setup, because it is not necessary to divide the color image into three channels and respectively recover them.
Michel, Pierre; Baumstarck, Karine; Ghattas, Badih; Pelletier, Jean; Loundou, Anderson; Boucekine, Mohamed; Auquier, Pascal; Boyer, Laurent
2016-04-01
The aim was to develop a multidimensional computerized adaptive short-form questionnaire, the MusiQoL-MCAT, from a fixed-length QoL questionnaire for multiple sclerosis.A total of 1992 patients were enrolled in this international cross-sectional study. The development of the MusiQoL-MCAT was based on the assessment of between-items MIRT model fit followed by real-data simulations. The MCAT algorithm was based on Bayesian maximum a posteriori estimation of latent traits and Kullback-Leibler information item selection. We examined several simulations based on a fixed number of items. Accuracy was assessed using correlations (r) between initial IRT scores and MCAT scores. Precision was assessed using the standard error measurement (SEM) and the root mean square error (RMSE).The multidimensional graded response model was used to estimate item parameters and IRT scores. Among the MCAT simulations, the 16-item version of the MusiQoL-MCAT was selected because the accuracy and precision became stable with 16 items with satisfactory levels (r ≥ 0.9, SEM ≤ 0.55, and RMSE ≤ 0.3). External validity of the MusiQoL-MCAT was satisfactory.The MusiQoL-MCAT presents satisfactory properties and can individually tailor QoL assessment to each patient, making it less burdensome to patients and better adapted for use in clinical practice.
Michel, Pierre; Baumstarck, Karine; Ghattas, Badih; Pelletier, Jean; Loundou, Anderson; Boucekine, Mohamed; Auquier, Pascal; Boyer, Laurent
2016-01-01
Abstract The aim was to develop a multidimensional computerized adaptive short-form questionnaire, the MusiQoL-MCAT, from a fixed-length QoL questionnaire for multiple sclerosis. A total of 1992 patients were enrolled in this international cross-sectional study. The development of the MusiQoL-MCAT was based on the assessment of between-items MIRT model fit followed by real-data simulations. The MCAT algorithm was based on Bayesian maximum a posteriori estimation of latent traits and Kullback–Leibler information item selection. We examined several simulations based on a fixed number of items. Accuracy was assessed using correlations (r) between initial IRT scores and MCAT scores. Precision was assessed using the standard error measurement (SEM) and the root mean square error (RMSE). The multidimensional graded response model was used to estimate item parameters and IRT scores. Among the MCAT simulations, the 16-item version of the MusiQoL-MCAT was selected because the accuracy and precision became stable with 16 items with satisfactory levels (r ≥ 0.9, SEM ≤ 0.55, and RMSE ≤ 0.3). External validity of the MusiQoL-MCAT was satisfactory. The MusiQoL-MCAT presents satisfactory properties and can individually tailor QoL assessment to each patient, making it less burdensome to patients and better adapted for use in clinical practice. PMID:27057832
Feature maps driven no-reference image quality prediction of authentically distorted images
NASA Astrophysics Data System (ADS)
Ghadiyaram, Deepti; Bovik, Alan C.
2015-03-01
Current blind image quality prediction models rely on benchmark databases comprised of singly and synthetically distorted images, thereby learning image features that are only adequate to predict human perceived visual quality on such inauthentic distortions. However, real world images often contain complex mixtures of multiple distortions. Rather than a) discounting the effect of these mixtures of distortions on an image's perceptual quality and considering only the dominant distortion or b) using features that are only proven to be efficient for singly distorted images, we deeply study the natural scene statistics of authentically distorted images, in different color spaces and transform domains. We propose a feature-maps-driven statistical approach which avoids any latent assumptions about the type of distortion(s) contained in an image, and focuses instead on modeling the remarkable consistencies in the scene statistics of real world images in the absence of distortions. We design a deep belief network that takes model-based statistical image features derived from a very large database of authentically distorted images as input and discovers good feature representations by generalizing over different distortion types, mixtures, and severities, which are later used to learn a regressor for quality prediction. We demonstrate the remarkable competence of our features for improving automatic perceptual quality prediction on a benchmark database and on the newly designed LIVE Authentic Image Quality Challenge Database and show that our approach of combining robust statistical features and the deep belief network dramatically outperforms the state-of-the-art.
Enders, Judith; Rief, Matthias; Zimmermann, Elke; Asbach, Patrick; Diederichs, Gerd; Wetz, Christoph; Siebert, Eberhard; Wagner, Moritz; Hamm, Bernd; Dewey, Marc
2013-01-01
The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR) imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. Altogether, 93 (80% women, mean age 53) consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR) and contrast-to-noise ratios (CNR), and quantitative contour sharpness. The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34-37% for the quantitative contour sharpness (P<0.0001). The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic) image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001). In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. ClinicalTrials.gov NCT00715806.
Zimmermann, Elke; Asbach, Patrick; Diederichs, Gerd; Wetz, Christoph; Siebert, Eberhard; Wagner, Moritz; Hamm, Bernd; Dewey, Marc
2013-01-01
Background The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR) imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. Methods Altogether, 93 (80% women, mean age 53) consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR) and contrast-to-noise ratios (CNR), and quantitative contour sharpness. Results The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34–37% for the quantitative contour sharpness (P<0.0001). The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic) image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001). Conclusions In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. Trial Registration ClinicalTrials.gov NCT00715806 PMID:24391767
Multiscale image processing and antiscatter grids in digital radiography.
Lo, Winnie Y; Hornof, William J; Zwingenberger, Allison L; Robertson, Ian D
2009-01-01
Scatter radiation is a source of noise and results in decreased signal-to-noise ratio and thus decreased image quality in digital radiography. We determined subjectively whether a digitally processed image made without a grid would be of similar quality to an image made with a grid but without image processing. Additionally the effects of exposure dose and of a using a grid with digital radiography on overall image quality were studied. Thoracic and abdominal radiographs of five dogs of various sizes were made. Four acquisition techniques were included (1) with a grid, standard exposure dose, digital image processing; (2) without a grid, standard exposure dose, digital image processing; (3) without a grid, half the exposure dose, digital image processing; and (4) with a grid, standard exposure dose, no digital image processing (to mimic a film-screen radiograph). Full-size radiographs as well as magnified images of specific anatomic regions were generated. Nine reviewers rated the overall image quality subjectively using a five-point scale. All digitally processed radiographs had higher overall scores than nondigitally processed radiographs regardless of patient size, exposure dose, or use of a grid. The images made at half the exposure dose had a slightly lower quality than those made at full dose, but this was only statistically significant in magnified images. Using a grid with digital image processing led to a slight but statistically significant increase in overall quality when compared with digitally processed images made without a grid but whether this increase in quality is clinically significant is unknown.
Hom, Erik F. Y.; Marchis, Franck; Lee, Timothy K.; Haase, Sebastian; Agard, David A.; Sedat, John W.
2011-01-01
We describe an adaptive image deconvolution algorithm (AIDA) for myopic deconvolution of multi-frame and three-dimensional data acquired through astronomical and microscopic imaging. AIDA is a reimplementation and extension of the MISTRAL method developed by Mugnier and co-workers and shown to yield object reconstructions with excellent edge preservation and photometric precision [J. Opt. Soc. Am. A 21, 1841 (2004)]. Written in Numerical Python with calls to a robust constrained conjugate gradient method, AIDA has significantly improved run times over the original MISTRAL implementation. Included in AIDA is a scheme to automatically balance maximum-likelihood estimation and object regularization, which significantly decreases the amount of time and effort needed to generate satisfactory reconstructions. We validated AIDA using synthetic data spanning a broad range of signal-to-noise ratios and image types and demonstrated the algorithm to be effective for experimental data from adaptive optics–equipped telescope systems and wide-field microscopy. PMID:17491626
Video see-through augmented reality for oral and maxillofacial surgery.
Wang, Junchen; Suenaga, Hideyuki; Yang, Liangjing; Kobayashi, Etsuko; Sakuma, Ichiro
2017-06-01
Oral and maxillofacial surgery has not been benefitting from image guidance techniques owing to the limitations in image registration. A real-time markerless image registration method is proposed by integrating a shape matching method into a 2D tracking framework. The image registration is performed by matching the patient's teeth model with intraoperative video to obtain its pose. The resulting pose is used to overlay relevant models from the same CT space on the camera video for augmented reality. The proposed system was evaluated on mandible/maxilla phantoms, a volunteer and clinical data. Experimental results show that the target overlay error is about 1 mm, and the frame rate of registration update yields 3-5 frames per second with a 4 K camera. The significance of this work lies in its simplicity in clinical setting and the seamless integration into the current medical procedure with satisfactory response time and overlay accuracy. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.