Sechopoulos, Ioannis
2013-01-01
Many important post-acquisition aspects of breast tomosynthesis imaging can impact its clinical performance. Chief among them is the reconstruction algorithm that generates the representation of the three-dimensional breast volume from the acquired projections. But even after reconstruction, additional processes, such as artifact reduction algorithms, computer aided detection and diagnosis, among others, can also impact the performance of breast tomosynthesis in the clinical realm. In this two part paper, a review of breast tomosynthesis research is performed, with an emphasis on its medical physics aspects. In the companion paper, the first part of this review, the research performed relevant to the image acquisition process is examined. This second part will review the research on the post-acquisition aspects, including reconstruction, image processing, and analysis, as well as the advanced applications being investigated for breast tomosynthesis. PMID:23298127
Grammatical verb aspect and event roles in sentence processing.
Madden-Lombardi, Carol; Dominey, Peter Ford; Ventre-Dominey, Jocelyne
2017-01-01
Two experiments examine how grammatical verb aspect constrains our understanding of events. According to linguistic theory, an event described in the perfect aspect (John had opened the bottle) should evoke a mental representation of a finished event with focus on the resulting object, whereas an event described in the imperfective aspect (John was opening the bottle) should evoke a representation of the event as ongoing, including all stages of the event, and focusing all entities relevant to the ongoing action (instruments, objects, agents, locations, etc.). To test this idea, participants saw rebus sentences in the perfect and imperfective aspect, presented one word at a time, self-paced. In each sentence, the instrument and the recipient of the action were replaced by pictures (John was using/had used a *corkscrew* to open the *bottle* at the restaurant). Time to process the two images as well as speed and accuracy on sensibility judgments were measured. Although experimental sentences always made sense, half of the object and instrument pictures did not match the temporal constraints of the verb. For instance, in perfect sentences aspect-congruent trials presented an image of the corkscrew closed (no longer in-use) and the wine bottle fully open. The aspect-incongruent yet still sensible versions either replaced the corkscrew with an in-use corkscrew (open, in-hand) or the bottle image with a half-opened bottle. In this case, the participant would still respond "yes", but with longer expected response times. A three-way interaction among Verb Aspect, Sentence Role, and Temporal Match on image processing times showed that participants were faster to process images that matched rather than mismatched the aspect of the verb, especially for resulting objects in perfect sentences. A second experiment replicated and extended the results to confirm that this was not due to the placement of the object in the sentence. These two experiments extend previous research, showing how verb aspect drives not only the temporal structure of event representation, but also the focus on specific roles of the event. More generally, the findings of visual match during online sentence-picture processing are consistent with theories of perceptual simulation.
Grammatical verb aspect and event roles in sentence processing
Madden-Lombardi, Carol; Dominey, Peter Ford; Ventre-Dominey, Jocelyne
2017-01-01
Two experiments examine how grammatical verb aspect constrains our understanding of events. According to linguistic theory, an event described in the perfect aspect (John had opened the bottle) should evoke a mental representation of a finished event with focus on the resulting object, whereas an event described in the imperfective aspect (John was opening the bottle) should evoke a representation of the event as ongoing, including all stages of the event, and focusing all entities relevant to the ongoing action (instruments, objects, agents, locations, etc.). To test this idea, participants saw rebus sentences in the perfect and imperfective aspect, presented one word at a time, self-paced. In each sentence, the instrument and the recipient of the action were replaced by pictures (John was using/had used a *corkscrew* to open the *bottle* at the restaurant). Time to process the two images as well as speed and accuracy on sensibility judgments were measured. Although experimental sentences always made sense, half of the object and instrument pictures did not match the temporal constraints of the verb. For instance, in perfect sentences aspect-congruent trials presented an image of the corkscrew closed (no longer in-use) and the wine bottle fully open. The aspect-incongruent yet still sensible versions either replaced the corkscrew with an in-use corkscrew (open, in-hand) or the bottle image with a half-opened bottle. In this case, the participant would still respond “yes”, but with longer expected response times. A three-way interaction among Verb Aspect, Sentence Role, and Temporal Match on image processing times showed that participants were faster to process images that matched rather than mismatched the aspect of the verb, especially for resulting objects in perfect sentences. A second experiment replicated and extended the results to confirm that this was not due to the placement of the object in the sentence. These two experiments extend previous research, showing how verb aspect drives not only the temporal structure of event representation, but also the focus on specific roles of the event. More generally, the findings of visual match during online sentence-picture processing are consistent with theories of perceptual simulation. PMID:29287091
Digital image analysis techniques for fiber and soil mixtures.
DOT National Transportation Integrated Search
1999-05-01
The objective of image processing is to visually enhance, quantify, and/or statistically evaluate some aspect of an image not readily apparent in its original form. Processed digital image data can be analyzed in numerous ways. In order to summarize ...
Microvax-based data management and reduction system for the regional planetary image facilities
NASA Technical Reports Server (NTRS)
Arvidson, R.; Guinness, E.; Slavney, S.; Weiss, B.
1987-01-01
Presented is a progress report for the Regional Planetary Image Facilities (RPIF) prototype image data management and reduction system being jointly implemented by Washington University and the USGS, Flagstaff. The system will consist of a MicroVAX with a high capacity (approx 300 megabyte) disk drive, a compact disk player, an image display buffer, a videodisk player, USGS image processing software, and SYSTEM 1032 - a commercial relational database management package. The USGS, Flagstaff, will transfer their image processing software including radiometric and geometric calibration routines, to the MicroVAX environment. Washington University will have primary responsibility for developing the database management aspects of the system and for integrating the various aspects into a working system.
Advances in medical image computing.
Tolxdorff, T; Deserno, T M; Handels, H; Meinzer, H-P
2009-01-01
Medical image computing has become a key technology in high-tech applications in medicine and an ubiquitous part of modern imaging systems and the related processes of clinical diagnosis and intervention. Over the past years significant progress has been made in the field, both on methodological and on application level. Despite this progress there are still big challenges to meet in order to establish image processing routinely in health care. In this issue, selected contributions of the German Conference on Medical Image Processing (BVM) are assembled to present latest advances in the field of medical image computing. The winners of scientific awards of the German Conference on Medical Image Processing (BVM) 2008 were invited to submit a manuscript on their latest developments and results for possible publication in Methods of Information in Medicine. Finally, seven excellent papers were selected to describe important aspects of recent advances in the field of medical image processing. The selected papers give an impression of the breadth and heterogeneity of new developments. New methods for improved image segmentation, non-linear image registration and modeling of organs are presented together with applications of image analysis methods in different medical disciplines. Furthermore, state-of-the-art tools and techniques to support the development and evaluation of medical image processing systems in practice are described. The selected articles describe different aspects of the intense development in medical image computing. The image processing methods presented enable new insights into the patient's image data and have the future potential to improve medical diagnostics and patient treatment.
Photography/Digital Imaging: Parallel & Paradoxical Histories.
ERIC Educational Resources Information Center
Witte, Mary Stieglitz
With the introduction of photography and photomechanical printing processes in the 19th century, the first age of machine pictures and reproductions emerged. The 20th century introduced computer image processing systems, creating a digital imaging revolution. Rather than concentrating on the adversarial aspects of the computer's influence on…
Physics of fractional imaging in biomedicine.
Sohail, Ayesha; Bég, O A; Li, Zhiwu; Celik, Sebahattin
2018-03-12
The mathematics of imaging is a growing field of research and is evolving rapidly parallel to evolution in the field of imaging. Imaging, which is a sub-field of biomedical engineering, considers novel approaches to visualize biological tissues with the general goal of improving health. "Medical imaging research provides improved diagnostic tools in clinical settings and supports the development of drugs and other therapies. The data acquisition and diagnostic interpretation with minimum error are the important technical aspects of medical imaging. The image quality and resolution are really important in portraying the internal aspects of patient's body. Although there are several user friendly resources for processing image features, such as enhancement, colour manipulation and compression, the development of new processing methods is still worthy of efforts. In this article we aim to present the role of fractional calculus in imaging with the aid of practical examples. Copyright © 2018 Elsevier Ltd. All rights reserved.
Image change detection systems, methods, and articles of manufacture
Jones, James L.; Lassahn, Gordon D.; Lancaster, Gregory D.
2010-01-05
Aspects of the invention relate to image change detection systems, methods, and articles of manufacture. According to one aspect, a method of identifying differences between a plurality of images is described. The method includes loading a source image and a target image into memory of a computer, constructing source and target edge images from the source and target images to enable processing of multiband images, displaying the source and target images on a display device of the computer, aligning the source and target edge images, switching displaying of the source image and the target image on the display device, to enable identification of differences between the source image and the target image.
Metric Aspects of Digital Images and Digital Image Processing.
1984-09-01
produced in a reconstructed digital image. Synthesized aerial photographs were formed by processing a combined elevation and orthophoto data base. These...brightness values h1 and Iion b) a line equation whose two parameters are calculated h12, along with tile borderline that separates the two intensity
Image processing and products for the Magellan mission to Venus
NASA Technical Reports Server (NTRS)
Clark, Jerry; Alexander, Doug; Andres, Paul; Lewicki, Scott; Mcauley, Myche
1992-01-01
The Magellan mission to Venus is providing planetary scientists with massive amounts of new data about the surface geology of Venus. Digital image processing is an integral part of the ground data system that provides data products to the investigators. The mosaicking of synthetic aperture radar (SAR) image data from the spacecraft is being performed at JPL's Multimission Image Processing Laboratory (MIPL). MIPL hosts and supports the Image Data Processing Subsystem (IDPS), which was developed in a VAXcluster environment of hardware and software that includes optical disk jukeboxes and the TAE-VICAR (Transportable Applications Executive-Video Image Communication and Retrieval) system. The IDPS is being used by processing analysts of the Image Data Processing Team to produce the Magellan image data products. Various aspects of the image processing procedure are discussed.
Three images of interdisciplinary team meetings.
Crepeau, E B
1994-08-01
Teams are an essential aspect of health care today, especially in rehabilitation or chronic illness where the course of care is frequently long, complex, and unpredictable. The coordinative function of teams and their interdisciplinary aspects are thought to improve patient care because team members bring their unique professional skills together to address patient problems. This coordination is enacted through the team meeting, which typically results in an integrated care plan. This professional image of team meetings is explicit and addresses the description and provision of care as objective and rational activities. In contrast, the constructed and ritualistic images of health care team meetings are implicit and concern the less objective and rational aspects of planning care. The constructed image pertains to the definitional activity of team members as they try to understand patient troubles and achieve consensus. This process involves the individual clinical reasoning of team members and the collective reasoning of the group. The ritualistic image is that aspect of team meetings in which the team affirms and reaffirms its collective identity. Drawing from field research of geropsychiatric team meetings, this article defines and explicates these images, focusing on the constructed and ritualistic aspects of team meetings and the influence of these images on group function.
Iplt--image processing library and toolkit for the electron microscopy community.
Philippsen, Ansgar; Schenk, Andreas D; Stahlberg, Henning; Engel, Andreas
2003-01-01
We present the foundation for establishing a modular, collaborative, integrated, open-source architecture for image processing of electron microscopy images, named iplt. It is designed around object oriented paradigms and implemented using the programming languages C++ and Python. In many aspects it deviates from classical image processing approaches. This paper intends to motivate developers within the community to participate in this on-going project. The iplt homepage can be found at http://www.iplt.org.
NASA Astrophysics Data System (ADS)
Zhan, Qi; Wang, Xin; Mu, Baozhong; Xu, Jie; Xie, Qing; Li, Yaran; Chen, Yifan; He, Yanan
2016-10-01
Dangerous materials inspection is an important technique to confirm dangerous materials crimes. It has significant impact on the prohibition of dangerous materials-related crimes and the spread of dangerous materials. Lobster-Eye Optical Imaging System is a kind of dangerous materials detection device which mainly takes advantage of backscatter X-ray. The strength of the system is its applicability to access only one side of an object, and to detect dangerous materials without disturbing the surroundings of the target material. The device uses Compton scattered x-rays to create computerized outlines of suspected objects during security detection process. Due to the grid structure of the bionic object glass, which imitate the eye of a lobster, grids contribute to the main image noise during the imaging process. At the same time, when used to inspect structured or dense materials, the image is plagued by superposition artifacts and limited by attenuation and noise. With the goal of achieving high quality images which could be used for dangerous materials detection and further analysis, we developed effective image process methods applied to the system. The first aspect of the image process is the denoising and enhancing edge contrast process, during the process, we apply deconvolution algorithm to remove the grids and other noises. After image processing, we achieve high signal-to-noise ratio image. The second part is to reconstruct image from low dose X-ray exposure condition. We developed a kind of interpolation method to achieve the goal. The last aspect is the region of interest (ROI) extraction process, which could be used to help identifying dangerous materials mixed with complex backgrounds. The methods demonstrated in the paper have the potential to improve the sensitivity and quality of x-ray backscatter system imaging.
NASA Technical Reports Server (NTRS)
Aldcroft, T.; Karovska, M.; Cresitello-Dittmar, M.; Cameron, R.
2000-01-01
The aspect system of the Chandra Observatory plays a key role in realizing the full potential of Chandra's x-ray optics and detectors. To achieve the highest spatial and spectral resolution (for grating observations), an accurate post-facto time history of the spacecraft attitude and internal alignment is needed. The CXC has developed a suite of tools which process sensor data from the aspect camera assembly and gyroscopes, and produce the spacecraft aspect solution. In this poster, the design of the aspect pipeline software is briefly described, followed by details of aspect system performance during the first eight months of flight. The two key metrics of aspect performance are: image reconstruction accuracy, which measures the x-ray image blurring introduced by aspect; and celestial location, which is the accuracy of detected source positions in absolute sky coordinates.
Photo-reconnaissance applications of computer processing of images.
NASA Technical Reports Server (NTRS)
Billingsley, F. C.
1972-01-01
Discussion of imaging processing techniques for enhancement and calibration of Jet Propulsion Laboratory imaging experiment pictures returned from NASA space vehicles such as Ranger, Mariner and Surveyor. Particular attention is given to data transmission, resolution vs recognition, and color aspects of digital data processing. The effectiveness of these techniques in applications to images from a wide variety of sources is noted. It is anticipated that the use of computer processing for enhancement of imagery will increase with the improvement and cost reduction of these techniques in the future.
VIEW-Station software and its graphical user interface
NASA Astrophysics Data System (ADS)
Kawai, Tomoaki; Okazaki, Hiroshi; Tanaka, Koichiro; Tamura, Hideyuki
1992-04-01
VIEW-Station is a workstation-based image processing system which merges the state-of-the- art software environment of Unix with the computing power of a fast image processor. VIEW- Station has a hierarchical software architecture, which facilitates device independence when porting across various hardware configurations, and provides extensibility in the development of application systems. The core image computing language is V-Sugar. V-Sugar provides a set of image-processing datatypes and allows image processing algorithms to be simply expressed, using a functional notation. VIEW-Station provides a hardware independent window system extension called VIEW-Windows. In terms of GUI (Graphical User Interface) VIEW-Station has two notable aspects. One is to provide various types of GUI as visual environments for image processing execution. Three types of interpreters called (mu) V- Sugar, VS-Shell and VPL are provided. Users may choose whichever they prefer based on their experience and tasks. The other notable aspect is to provide facilities to create GUI for new applications on the VIEW-Station system. A set of widgets are available for construction of task-oriented GUI. A GUI builder called VIEW-Kid is developed for WYSIWYG interactive interface design.
Counting Craters on MOC Images: Production Functions and Other Complications
NASA Technical Reports Server (NTRS)
Plaut, J. J.
2001-01-01
New crater counts on MOC images and associated Viking Orbiter images are used to address the issue of the crater production function at Mars, and to infer aspects of resurfacing processes. Additional information is contained in the original extended abstract.
SSME propellant path leak detection real-time
NASA Technical Reports Server (NTRS)
Crawford, R. A.; Smith, L. M.
1994-01-01
Included are four documents that outline the technical aspects of the research performed on NASA Grant NAG8-140: 'A System for Sequential Step Detection with Application to Video Image Processing'; 'Leak Detection from the SSME Using Sequential Image Processing'; 'Digital Image Processor Specifications for Real-Time SSME Leak Detection'; and 'A Color Change Detection System for Video Signals with Applications to Spectral Analysis of Rocket Engine Plumes'.
Investigation of 1 : 1,000 Scale Map Generation by Stereo Plotting Using Uav Images
NASA Astrophysics Data System (ADS)
Rhee, S.; Kim, T.
2017-08-01
Large scale maps and image mosaics are representative geospatial data that can be extracted from UAV images. Map drawing using UAV images can be performed either by creating orthoimages and digitizing them, or by stereo plotting. While maps generated by digitization may serve the need for geospatial data, many institutions and organizations require map drawing using stereoscopic vision on stereo plotting systems. However, there are several aspects to be checked for UAV images to be utilized for stereo plotting. The first aspect is the accuracy of exterior orientation parameters (EOPs) generated through automated bundle adjustment processes. It is well known that GPS and IMU sensors mounted on a UAV are not very accurate. It is necessary to adjust initial EOPs accurately using tie points. For this purpose, we have developed a photogrammetric incremental bundle adjustment procedure. The second aspect is unstable shooting conditions compared to aerial photographing. Unstable image acquisition may bring uneven stereo coverage, which will result in accuracy loss eventually. Oblique stereo pairs will create eye fatigue. The third aspect is small coverage of UAV images. This aspect will raise efficiency issue for stereo plotting of UAV images. More importantly, this aspect will make contour generation from UAV images very difficult. This paper will discuss effects relate to these three aspects. In this study, we tried to generate 1 : 1,000 scale map from the dataset using EOPs generated from software developed in-house. We evaluated Y-disparity of the tie points extracted automatically through the photogrammetric incremental bundle adjustment process. We could confirm that stereoscopic viewing is possible. Stereoscopic plotting work was carried out by a professional photogrammetrist. In order to analyse the accuracy of the map drawing using stereoscopic vision, we compared the horizontal and vertical position difference between adjacent models after drawing a specific model. The results of analysis showed that the errors were within the specification of 1 : 1,000 map. Although the Y-parallax can be eliminated, it is still necessary to improve the accuracy of absolute ground position error in order to apply this technique to the actual work. There are a few models in which the difference in height between adjacent models is about 40 cm. We analysed the stability of UAV images by checking angle differences between adjacent images. We also analysed the average area covered by one stereo model and discussed the possible difficulty associated with this narrow coverage. In the future we consider how to reduce position errors and improve map drawing performances from UAVs.
Fabrication of absorption gratings with X-ray lithography for X-ray phase contrast imaging
NASA Astrophysics Data System (ADS)
Wang, Bo; Wang, Yu-Ting; Yi, Fu-Ting; Zhang, Tian-Chong; Liu, Jing; Zhou, Yue
2018-05-01
Grating-based X-ray phase contrast imaging is promising especially in the medical area. Two or three gratings are involved in grating-based X-ray phase contrast imaging in which the absorption grating of high-aspect-ratio is the most important device and the fabrication process is a great challenge. The material with large atomic number Z is used to fabricate the absorption grating for excellent absorption of X-ray, and Au is usually used. The fabrication process, which involves X-ray lithography, development and gold electroplating, is described in this paper. The absorption gratings with 4 μm period and about 100 μm height are fabricated and the high-aspect-ratio is 50.
Technical aspects of CT imaging of the spine.
Tins, Bernhard
2010-11-01
This review article discusses technical aspects of computed tomography (CT) imaging of the spine. Patient positioning, and its influence on image quality and movement artefact, is discussed. Particular emphasis is placed on the choice of scan parameters and their relation to image quality and radiation burden to the patient. Strategies to reduce radiation burden and artefact from metal implants are outlined. Data acquisition, processing, image display and steps to reduce artefact are reviewed. CT imaging of the spine is put into context with other imaging modalities for specific clinical indications or problems. This review aims to review underlying principles for image acquisition and to provide a rough guide for clinical problems without being prescriptive. Individual practice will always vary and reflect differences in local experience, technical provisions and clinical requirements.
Hybrid vision activities at NASA Johnson Space Center
NASA Technical Reports Server (NTRS)
Juday, Richard D.
1990-01-01
NASA's Johnson Space Center in Houston, Texas, is active in several aspects of hybrid image processing. (The term hybrid image processing refers to a system that combines digital and photonic processing). The major thrusts are autonomous space operations such as planetary landing, servicing, and rendezvous and docking. By processing images in non-Cartesian geometries to achieve shift invariance to canonical distortions, researchers use certain aspects of the human visual system for machine vision. That technology flow is bidirectional; researchers are investigating the possible utility of video-rate coordinate transformations for human low-vision patients. Man-in-the-loop teleoperations are also supported by the use of video-rate image-coordinate transformations, as researchers plan to use bandwidth compression tailored to the varying spatial acuity of the human operator. Technological elements being developed in the program include upgraded spatial light modulators, real-time coordinate transformations in video imagery, synthetic filters that robustly allow estimation of object pose parameters, convolutionally blurred filters that have continuously selectable invariance to such image changes as magnification and rotation, and optimization of optical correlation done with spatial light modulators that have limited range and couple both phase and amplitude in their response.
Analyzing microtomography data with Python and the scikit-image library.
Gouillart, Emmanuelle; Nunez-Iglesias, Juan; van der Walt, Stéfan
2017-01-01
The exploration and processing of images is a vital aspect of the scientific workflows of many X-ray imaging modalities. Users require tools that combine interactivity, versatility, and performance. scikit-image is an open-source image processing toolkit for the Python language that supports a large variety of file formats and is compatible with 2D and 3D images. The toolkit exposes a simple programming interface, with thematic modules grouping functions according to their purpose, such as image restoration, segmentation, and measurements. scikit-image users benefit from a rich scientific Python ecosystem that contains many powerful libraries for tasks such as visualization or machine learning. scikit-image combines a gentle learning curve, versatile image processing capabilities, and the scalable performance required for the high-throughput analysis of X-ray imaging data.
Search systems and computer-implemented search methods
Payne, Deborah A.; Burtner, Edwin R.; Hampton, Shawn D.; Gillen, David S.; Henry, Michael J.
2017-03-07
Search systems and computer-implemented search methods are described. In one aspect, a search system includes a communications interface configured to access a plurality of data items of a collection, wherein the data items include a plurality of image objects individually comprising image data utilized to generate an image of the respective data item. The search system may include processing circuitry coupled with the communications interface and configured to process the image data of the data items of the collection to identify a plurality of image content facets which are indicative of image content contained within the images and to associate the image objects with the image content facets and a display coupled with the processing circuitry and configured to depict the image objects associated with the image content facets.
Search systems and computer-implemented search methods
Payne, Deborah A.; Burtner, Edwin R.; Bohn, Shawn J.; Hampton, Shawn D.; Gillen, David S.; Henry, Michael J.
2015-12-22
Search systems and computer-implemented search methods are described. In one aspect, a search system includes a communications interface configured to access a plurality of data items of a collection, wherein the data items include a plurality of image objects individually comprising image data utilized to generate an image of the respective data item. The search system may include processing circuitry coupled with the communications interface and configured to process the image data of the data items of the collection to identify a plurality of image content facets which are indicative of image content contained within the images and to associate the image objects with the image content facets and a display coupled with the processing circuitry and configured to depict the image objects associated with the image content facets.
ERIC Educational Resources Information Center
Bentolila, Alain
1977-01-01
Syntactic analysis identifies the "conductor wires" permitting the listener to conceptualize the speaker's image of reality from information furnished by the linguistic message. Syntactic study is thus situated in the economy of the communication process. Mood, aspect and tense are studied in this framework. (Text is in French.) (AMH)
NASA Astrophysics Data System (ADS)
Chockalingam, Letchumanan
2005-01-01
The data of Gunung Ledang region of Malaysia acquired through LANDSAT are considered to map certain hydrogeolocial features. To map these significant features, image-processing tools such as contrast enhancement, edge detection techniques are employed. The advantages of these techniques over the other methods are evaluated from the point of their validity in properly isolating features of hydrogeolocial interest are discussed. As these techniques take the advantage of spectral aspects of the images, these techniques have several limitations to meet the objectives. To discuss these limitations, a morphological transformation, which generally considers the structural aspects rather than spectral aspects from the image, are applied to provide comparisons between the results derived from spectral based and the structural based filtering techniques.
Sherlock, C; Mair, T; Blunden, T
2008-11-01
Erosion of the palmar (flexor) aspect of the navicular bone is difficult to diagnose with conventional imaging techniques. To review the clinical, magnetic resonance (MR) and pathological features of deep erosions of the palmar aspect of the navicular bone. Cases of deep erosions of the palmar aspect of the navicular bone, diagnosed by standing low field MR imaging, were selected. Clinical details, results of diagnostic procedures, MR features and pathological findings were reviewed. Deep erosions of the palmar aspect of the navicular bone were diagnosed in 16 mature horses, 6 of which were bilaterally lame. Sudden onset of lameness was recorded in 63%. Radiography prior to MR imaging showed equivocal changes in 7 horses. The MR features consisted of focal areas of intermediate or high signal intensity on T1-, T2*- and T2-weighted images and STIR images affecting the dorsal aspect of the deep digital flexor tendon, the fibrocartilage of the palmar aspect, subchondral compact bone and medulla of the navicular bone. On follow-up, 7/16 horses (44%) had been subjected to euthanasia and only one was being worked at its previous level. Erosions of the palmar aspect of the navicular bone were confirmed post mortem in 2 horses. Histologically, the lesions were characterised by localised degeneration of fibrocartilage with underlying focal osteonecrosis and fibroplasia. The adjacent deep digital flexor tendon showed fibril formation and fibrocartilaginous metaplasia. Deep erosions of the palmar aspect of the navicular bone are more easily diagnosed by standing low field MR imaging than by conventional radiography. The lesions involve degeneration of the palmar fibrocartilage with underlying osteonecrosis and fibroplasia affecting the subchondral compact bone and medulla, and carry a poor prognosis for return to performance. Diagnosis of shallow erosive lesions of the palmar fibrocartilage may allow therapeutic intervention earlier in the disease process, thereby preventing progression to deep erosive lesions.
Empathy-Related Responses to Depicted People in Art Works
Kesner, Ladislav; Horáček, Jiří
2017-01-01
Existing theories of empathic response to visual art works postulate the primacy of automatic embodied reaction to images based on mirror neuron mechanisms. Arguing for a more inclusive concept of empathy-related response and integrating four distinct bodies of literature, we discuss contextual, and personal factors which modulate empathic response to depicted people. We then present an integrative model of empathy-related responses to depicted people in art works. The model assumes that a response to empathy-eliciting figural artworks engages the dynamic interaction of two mutually interlinked sets of processes: socio-affective/cognitive processing, related to the person perception, and esthetic processing, primarily concerned with esthetic appreciation and judgment and attention to non-social aspects of the image. The model predicts that the specific pattern of interaction between empathy-related and esthetic processing is co-determined by several sets of factors: (i) the viewer's individual characteristics, (ii) the context variables (which include various modes of priming by narratives and other images), (iii) multidimensional features of the image, and (iv) aspects of a viewer's response. Finally we propose that the model is implemented by the interaction of functionally connected brain networks involved in socio-cognitive and esthetic processing. PMID:28286487
The Statistics of Visual Representation
NASA Technical Reports Server (NTRS)
Jobson, Daniel J.; Rahman, Zia-Ur; Woodell, Glenn A.
2002-01-01
The experience of retinex image processing has prompted us to reconsider fundamental aspects of imaging and image processing. Foremost is the idea that a good visual representation requires a non-linear transformation of the recorded (approximately linear) image data. Further, this transformation appears to converge on a specific distribution. Here we investigate the connection between numerical and visual phenomena. Specifically the questions explored are: (1) Is there a well-defined consistent statistical character associated with good visual representations? (2) Does there exist an ideal visual image? And (3) what are its statistical properties?
Single-Cell and Single-Molecule Analysis of Gene Expression Regulation.
Vera, Maria; Biswas, Jeetayu; Senecal, Adrien; Singer, Robert H; Park, Hye Yoon
2016-11-23
Recent advancements in single-cell and single-molecule imaging technologies have resolved biological processes in time and space that are fundamental to understanding the regulation of gene expression. Observations of single-molecule events in their cellular context have revealed highly dynamic aspects of transcriptional and post-transcriptional control in eukaryotic cells. This approach can relate transcription with mRNA abundance and lifetimes. Another key aspect of single-cell analysis is the cell-to-cell variability among populations of cells. Definition of heterogeneity has revealed stochastic processes, determined characteristics of under-represented cell types or transitional states, and integrated cellular behaviors in the context of multicellular organisms. In this review, we discuss novel aspects of gene expression of eukaryotic cells and multicellular organisms revealed by the latest advances in single-cell and single-molecule imaging technology.
Intensity dependent spread theory
NASA Technical Reports Server (NTRS)
Holben, Richard
1990-01-01
The Intensity Dependent Spread (IDS) procedure is an image-processing technique based on a model of the processing which occurs in the human visual system. IDS processing is relevant to many aspects of machine vision and image processing. For quantum limited images, it produces an ideal trade-off between spatial resolution and noise averaging, performs edge enhancement thus requiring only mean-crossing detection for the subsequent extraction of scene edges, and yields edge responses whose amplitudes are independent of scene illumination, depending only upon the ratio of the reflectance on the two sides of the edge. These properties suggest that the IDS process may provide significant bandwidth reduction while losing only minimal scene information when used as a preprocessor at or near the image plane.
Liver CT image processing: a short introduction of the technical elements.
Masutani, Y; Uozumi, K; Akahane, Masaaki; Ohtomo, Kuni
2006-05-01
In this paper, we describe the technical aspects of image analysis for liver diagnosis and treatment, including the state-of-the-art of liver image analysis and its applications. After discussion on modalities for liver image analysis, various technical elements for liver image analysis such as registration, segmentation, modeling, and computer-assisted detection are covered with examples performed with clinical data sets. Perspective in the imaging technologies is also reviewed and discussed.
User Preferences in Image Map Using
NASA Astrophysics Data System (ADS)
Vondráková, A.; Vozenilek, V.
2016-06-01
In the process of map making, the attention is given to the resulting image map (to be accurate, readable, and suit the primary purpose) and its user aspects. Current cartography understands the user issues as all matters relating to user perception, map use and also user preferences. Most commercial cartographic production is strongly connected to economic circumstances. Companies are discovering user's interests and market demands. However, is it sufficient to focus just on the user's preferences? Recent research on user aspects at Palacký University Olomouc addresses a much wider scope of user aspects. The user's preferences are very often distorting - the users think that the particular image map is kind, beautiful, and useful and they wants to buy it (or use it - it depends on the form of the map production). But when the same user gets the task to use practically this particular map (such as finding the shortest way), so the user concludes that initially preferred map is useless, and uses a map, that was worse evaluated according to his preferences. It is, therefore, necessary to evaluate not only the correctness of image maps and their aesthetics but also to assess the user perception and other user issues. For the accomplishment of such testing, eye-tracking technology is a useful tool. The research analysed how users read image maps, or if they prefer image maps over traditional maps. The eye tracking experiment on the comparison of the conventional and image map reading was conducted. The map readers were asked to solve few simple tasks with either conventional or image map. The readers' choice of the map to solve the task was one of investigated aspect of user preferences. Results demonstrate that the user preferences and user needs are often quite different issues. The research outcomes show that it is crucial to implement map user testing into the cartographic production process.
Spatial Scale in Image Detection and Recognition.
1986-02-01
detail and are important in later visual processing when attention has been focused on a particular aspect of the image. Two experiments investigated the...observers also selected the filter condition to be display on each trial prior to the detection or recognition response.
Applications based on restored satellite images
NASA Astrophysics Data System (ADS)
Arbel, D.; Levin, S.; Nir, M.; Bhasteker, I.
2005-08-01
Satellites orbit the earth and obtain imagery of the ground below. The quality of satellite images is affected by the properties of the atmospheric imaging path, which degrade the image by blurring it and reducing its contrast. Applications involving satellite images are many and varied. Imaging systems are also different technologically and in their physical and optical characteristics such as sensor types, resolution, field of view (FOV), spectral range of the acquiring channels - from the visible to the thermal IR (TIR), platforms (mobilization facilities; aircrafts and/or spacecrafts), altitude above ground surface etc. It is important to obtain good quality satellite images because of the variety of applications based on them. The more qualitative is the recorded image, the more information is yielded from the image. The restoration process is conditioned by gathering much data about the atmospheric medium and its characterization. In return, there is a contribution to the applications based on those restorations i.e., satellite communication, warfare against long distance missiles, geographical aspects, agricultural aspects, economical aspects, intelligence, security, military, etc. Several manners to use restored Landsat 7 enhanced thematic mapper plus (ETM+) satellite images are suggested and presented here. In particular, using the restoration results for few potential geographical applications such as color classification and mapping (roads and streets localization) methods.
Neuroimaging Techniques: a Conceptual Overview of Physical Principles, Contribution and History
NASA Astrophysics Data System (ADS)
Minati, Ludovico
2006-06-01
This paper is meant to provide a brief overview of the techniques currently used to image the brain and to study non-invasively its anatomy and function. After a historical summary in the first section, general aspects are outlined in the second section. The subsequent six sections survey, in order, computed tomography (CT), morphological magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion-tensor magnetic resonance imaging (DWI/DTI), positron emission tomography (PET), and electro- and magneto-encephalography (EEG/MEG) based imaging. Underlying physical principles, modelling and data processing approaches, as well as clinical and research relevance are briefly outlined for each technique. Given the breadth of the scope, there has been no attempt to be comprehensive. The ninth and final section outlines some aspects of active research in neuroimaging.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Minati, Ludovico
This paper is meant to provide a brief overview of the techniques currently used to image the brain and to study non-invasively its anatomy and function. After a historical summary in the first section, general aspects are outlined in the second section. The subsequent six sections survey, in order, computed tomography (CT), morphological magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion-tensor magnetic resonance imaging (DWI/DTI), positron emission tomography (PET), and electro- and magneto-encephalography (EEG/MEG) based imaging. Underlying physical principles, modelling and data processing approaches, as well as clinical and research relevance are briefly outlined for each technique. Givenmore » the breadth of the scope, there has been no attempt to be comprehensive. The ninth and final section outlines some aspects of active research in neuroimaging.« less
Processing techniques for digital sonar images from GLORIA.
Chavez, P.S.
1986-01-01
Image processing techniques have been developed to handle data from one of the newest members of the remote sensing family of digital imaging systems. This paper discusses software to process data collected by the GLORIA (Geological Long Range Inclined Asdic) sonar imaging system, designed and built by the Institute of Oceanographic Sciences (IOS) in England, to correct for both geometric and radiometric distortions that exist in the original 'raw' data. Preprocessing algorithms that are GLORIA-specific include corrections for slant-range geometry, water column offset, aspect ratio distortion, changes in the ship's velocity, speckle noise, and shading problems caused by the power drop-off which occurs as a function of range.-from Author
Masedunskas, Andrius; Milberg, Oleg; Porat-Shliom, Natalie; Sramkova, Monika; Wigand, Tim; Amornphimoltham, Panomwat; Weigert, Roberto
2012-01-01
Intravital microscopy is an extremely powerful tool that enables imaging several biological processes in live animals. Recently, the ability to image subcellular structures in several organs combined with the development of sophisticated genetic tools has made possible extending this approach to investigate several aspects of cell biology. Here we provide a general overview of intravital microscopy with the goal of highlighting its potential and challenges. Specifically, this review is geared toward researchers that are new to intravital microscopy and focuses on practical aspects of carrying out imaging in live animals. Here we share the know-how that comes from first-hand experience, including topics such as choosing the right imaging platform and modality, surgery and stabilization techniques, anesthesia and temperature control. Moreover, we highlight some of the approaches that facilitate subcellular imaging in live animals by providing numerous examples of imaging selected organelles and the actin cytoskeleton in multiple organs. PMID:22992750
The Television Generation, Television Literacy, and Television Trends.
ERIC Educational Resources Information Center
Cohen, Jodi R.
Unlike the linear, serial process of reading books, learning to "read" television is a parallel process in which multiple pieces of information are simultaneously received. Perceiving images, only one aspect of understanding television, requires the concurrent processing of information that is compounded within a symbol system. The…
NASA Astrophysics Data System (ADS)
Rocha, José Celso; Passalia, Felipe José; Matos, Felipe Delestro; Takahashi, Maria Beatriz; Maserati, Marc Peter, Jr.; Alves, Mayra Fernanda; de Almeida, Tamie Guibu; Cardoso, Bruna Lopes; Basso, Andrea Cristina; Nogueira, Marcelo Fábio Gouveia
2017-12-01
There is currently no objective, real-time and non-invasive method for evaluating the quality of mammalian embryos. In this study, we processed images of in vitro produced bovine blastocysts to obtain a deeper comprehension of the embryonic morphological aspects that are related to the standard evaluation of blastocysts. Information was extracted from 482 digital images of blastocysts. The resulting imaging data were individually evaluated by three experienced embryologists who graded their quality. To avoid evaluation bias, each image was related to the modal value of the evaluations. Automated image processing produced 36 quantitative variables for each image. The images, the modal and individual quality grades, and the variables extracted could potentially be used in the development of artificial intelligence techniques (e.g., evolutionary algorithms and artificial neural networks), multivariate modelling and the study of defined structures of the whole blastocyst.
Present status and trends of image fusion
NASA Astrophysics Data System (ADS)
Xiang, Dachao; Fu, Sheng; Cai, Yiheng
2009-10-01
Image fusion information extracted from multiple images which is more accurate and reliable than that from just a single image. Since various images contain different information aspects of the measured parts, and comprehensive information can be obtained by integrating them together. Image fusion is a main branch of the application of data fusion technology. At present, it was widely used in computer vision technology, remote sensing, robot vision, medical image processing and military field. This paper mainly presents image fusion's contents, research methods, and the status quo at home and abroad, and analyzes the development trend.
Art Therapy and Its Contemplative Nature: Unifying Aspects of Image Making
ERIC Educational Resources Information Center
Salom, Andrée
2013-01-01
This article describes an art-based inquiry that explored two contemplative strategies--the conceptual strategy and the awareness strategy--through observation of art images and processes of creation, conceptual understanding, assessment, and the inner movements of self-awareness. Art media and directives were used to subjectively test key…
NASA Astrophysics Data System (ADS)
Verrelst, Jochem; Malenovský, Zbyněk; Van der Tol, Christiaan; Camps-Valls, Gustau; Gastellu-Etchegorry, Jean-Philippe; Lewis, Philip; North, Peter; Moreno, Jose
2018-06-01
An unprecedented spectroscopic data stream will soon become available with forthcoming Earth-observing satellite missions equipped with imaging spectroradiometers. This data stream will open up a vast array of opportunities to quantify a diversity of biochemical and structural vegetation properties. The processing requirements for such large data streams require reliable retrieval techniques enabling the spatiotemporally explicit quantification of biophysical variables. With the aim of preparing for this new era of Earth observation, this review summarizes the state-of-the-art retrieval methods that have been applied in experimental imaging spectroscopy studies inferring all kinds of vegetation biophysical variables. Identified retrieval methods are categorized into: (1) parametric regression, including vegetation indices, shape indices and spectral transformations; (2) nonparametric regression, including linear and nonlinear machine learning regression algorithms; (3) physically based, including inversion of radiative transfer models (RTMs) using numerical optimization and look-up table approaches; and (4) hybrid regression methods, which combine RTM simulations with machine learning regression methods. For each of these categories, an overview of widely applied methods with application to mapping vegetation properties is given. In view of processing imaging spectroscopy data, a critical aspect involves the challenge of dealing with spectral multicollinearity. The ability to provide robust estimates, retrieval uncertainties and acceptable retrieval processing speed are other important aspects in view of operational processing. Recommendations towards new-generation spectroscopy-based processing chains for operational production of biophysical variables are given.
Lunar Regolith Particle Shape Analysis
NASA Technical Reports Server (NTRS)
Kiekhaefer, Rebecca; Hardy, Sandra; Rickman, Douglas; Edmunson, Jennifer
2013-01-01
Future engineering of structures and equipment on the lunar surface requires significant understanding of particle characteristics of the lunar regolith. Nearly all sediment characteristics are influenced by particle shape; therefore a method of quantifying particle shape is useful both in lunar and terrestrial applications. We have created a method to quantify particle shape, specifically for lunar regolith, using image processing. Photomicrographs of thin sections of lunar core material were obtained under reflected light. Three photomicrographs were analyzed using ImageJ and MATLAB. From the image analysis measurements for area, perimeter, Feret diameter, orthogonal Feret diameter, Heywood factor, aspect ratio, sieve diameter, and sieve number were recorded. Probability distribution functions were created from the measurements of Heywood factor and aspect ratio.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluationmore » of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base. (TEM)« less
ERIC Educational Resources Information Center
Vorstenbosch, Marc A. T. M.; Bouter, Shifra T.; van den Hurk, Marianne M.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.
2014-01-01
Assessment is an important aspect of medical education because it tests students' competence and motivates them to study. Various assessment methods, with and without images, are used in the study of anatomy. In this study, we investigated the use of extended matching questions (EMQs). To gain insight into the influence of images on the…
Modified Pressure System for Imaging Egg Cracks
USDA-ARS?s Scientific Manuscript database
One aspect of grading table eggs is shell checks or cracks. Currently, USDA voluntary regulations require that humans grade a representative sample of all eggs processed. However, as processing plants and packing facilities continue to increase their volume and throughput, human graders are having ...
Modified Pressure System for Imaging Egg Cracks
USDA-ARS?s Scientific Manuscript database
Abstract One aspect of grading table eggs is shell checks or cracks. Currently, USDA voluntary regulations require that humans grade a representative sample of all eggs processed. However, as processing plants and packing facilities continue to increase their volume and throughput, human graders a...
Quantitative Aspects of Single Molecule Microscopy
Ober, Raimund J.; Tahmasbi, Amir; Ram, Sripad; Lin, Zhiping; Ward, E. Sally
2015-01-01
Single molecule microscopy is a relatively new optical microscopy technique that allows the detection of individual molecules such as proteins in a cellular context. This technique has generated significant interest among biologists, biophysicists and biochemists, as it holds the promise to provide novel insights into subcellular processes and structures that otherwise cannot be gained through traditional experimental approaches. Single molecule experiments place stringent demands on experimental and algorithmic tools due to the low signal levels and the presence of significant extraneous noise sources. Consequently, this has necessitated the use of advanced statistical signal and image processing techniques for the design and analysis of single molecule experiments. In this tutorial paper, we provide an overview of single molecule microscopy from early works to current applications and challenges. Specific emphasis will be on the quantitative aspects of this imaging modality, in particular single molecule localization and resolvability, which will be discussed from an information theoretic perspective. We review the stochastic framework for image formation, different types of estimation techniques and expressions for the Fisher information matrix. We also discuss several open problems in the field that demand highly non-trivial signal processing algorithms. PMID:26167102
NASA Astrophysics Data System (ADS)
Attention is given to aspects of quality assurance methodologies in development life cycles, optical intercity transmission systems, multiaccess protocols, system and technology aspects in the case of regional/domestic satellites, advances in SSB-AM radio transmission over terrestrial and satellite network, and development environments for telecommunications systems. Other subjects studied are concerned with business communication networks for voice and data, VLSI in local network and communication protocol, product evaluation and support, an update regarding Videotex, topics in communication theory, topics in radio propagation, a status report regarding societal effects of technology in the workplace, digital image processing, and adaptive signal processing for communications. The management of the reliability function in the development process is considered along with Giga-bit technologies for long distance large capacity optical transmission equipment. The application of gallium arsenide analog and digital integrated circuits for high-speed fiber optical communications, and a simple algorithm for image data coding.
Quantitative analysis of cardiovascular MR images.
van der Geest, R J; de Roos, A; van der Wall, E E; Reiber, J H
1997-06-01
The diagnosis of cardiovascular disease requires the precise assessment of both morphology and function. Nearly all aspects of cardiovascular function and flow can be quantified nowadays with fast magnetic resonance (MR) imaging techniques. Conventional and breath-hold cine MR imaging allow the precise and highly reproducible assessment of global and regional left ventricular function. During the same examination, velocity encoded cine (VEC) MR imaging provides measurements of blood flow in the heart and great vessels. Quantitative image analysis often still relies on manual tracing of contours in the images. Reliable automated or semi-automated image analysis software would be very helpful to overcome the limitations associated with the manual and tedious processing of the images. Recent progress in MR imaging of the coronary arteries and myocardial perfusion imaging with contrast media, along with the further development of faster imaging sequences, suggest that MR imaging could evolve into a single technique ('one stop shop') for the evaluation of many aspects of heart disease. As a result, it is very likely that the need for automated image segmentation and analysis software algorithms will further increase. In this paper the developments directed towards the automated image analysis and semi-automated contour detection for cardiovascular MR imaging are presented.
Population-based imaging biobanks as source of big data.
Gatidis, Sergios; Heber, Sophia D; Storz, Corinna; Bamberg, Fabian
2017-06-01
Advances of computational sciences over the last decades have enabled the introduction of novel methodological approaches in biomedical research. Acquiring extensive and comprehensive data about a research subject and subsequently extracting significant information has opened new possibilities in gaining insight into biological and medical processes. This so-called big data approach has recently found entrance into medical imaging and numerous epidemiological studies have been implementing advanced imaging to identify imaging biomarkers that provide information about physiological processes, including normal development and aging but also on the development of pathological disease states. The purpose of this article is to present existing epidemiological imaging studies and to discuss opportunities, methodological and organizational aspects, and challenges that population imaging poses to the field of big data research.
NASA Technical Reports Server (NTRS)
Watson, Andrew B.
1988-01-01
Two types of research issues are involved in image management systems with space station applications: image processing research and image perception research. The image processing issues are the traditional ones of digitizing, coding, compressing, storing, analyzing, and displaying, but with a new emphasis on the constraints imposed by the human perceiver. Two image coding algorithms have been developed that may increase the efficiency of image management systems (IMS). Image perception research involves a study of the theoretical and practical aspects of visual perception of electronically displayed images. Issues include how rapidly a user can search through a library of images, how to make this search more efficient, and how to present images in terms of resolution and split screens. Other issues include optimal interface to an IMS and how to code images in a way that is optimal for the human perceiver. A test-bed within which such issues can be addressed has been designed.
Optical method for measuring the surface area of a threaded fastener
Douglas Rammer; Samuel Zelinka
2010-01-01
This article highlights major aspects of a new optical technique to determine the surface area of a threaded fastener; the theoretical framework has been reported elsewhere. Specifically, this article describes general surface area expressions used in the analysis, details of image acquisition system, and major image processing steps contained within the measurement...
Spinning Disk Confocal Imaging of Neutrophil Migration in Zebrafish
Lam, Pui-ying; Fischer, Robert S; Shin, William D.; Waterman, Clare M; Huttenlocher, Anna
2014-01-01
Live-cell imaging techniques have been substantially improved due to advances in confocal microscopy instrumentation coupled with ultrasensitive detectors. The spinning disk confocal system is capable of generating images of fluorescent live samples with broad dynamic range and high temporal and spatial resolution. The ability to acquire fluorescent images of living cells in vivo on a millisecond timescale allows the dissection of biological processes that have not previously been visualized in a physiologically relevant context. In vivo imaging of rapidly moving cells such as neutrophils can be technically challenging. In this chapter, we describe the practical aspects of imaging neutrophils in zebrafish embryos using spinning disk confocal microscopy. Similar setups can also be applied to image other motile cell types and signaling processes in translucent animals or tissues. PMID:24504955
The effect of a brief mindfulness induction on processing of emotional images: an ERP study.
Eddy, Marianna D; Brunyé, Tad T; Tower-Richardi, Sarah; Mahoney, Caroline R; Taylor, Holly A
2015-01-01
The ability to effectively direct one's attention is an important aspect of regulating emotions and a component of mindfulness. Mindfulness practices have been established as effective interventions for mental and physical illness; however, the underlying neural mechanisms of mindfulness and how they relate to emotional processing have not been explored in depth. The current study used a within-subjects repeated measures design to examine if focused breathing, a brief mindfulness induction, could modulate event-related potentials (ERPs) during emotional image processing relative to a control condition. We related ERP measures of processing positive, negative, and neutral images (the P300 and late positive potential - LPP) to state and trait mindfulness measures. Overall, the brief mindfulness induction condition did not influence ERPs reflecting emotional processing; however, in the brief mindfulness induction condition, those participants who reported feeling more decentered (a subscale of the Toronto Mindfulness Scale) after viewing the images had reduced P300 responses to negative versus neutral images.
The effect of a brief mindfulness induction on processing of emotional images: an ERP study
Eddy, Marianna D.; Brunyé, Tad T.; Tower-Richardi, Sarah; Mahoney, Caroline R.; Taylor, Holly A.
2015-01-01
The ability to effectively direct one’s attention is an important aspect of regulating emotions and a component of mindfulness. Mindfulness practices have been established as effective interventions for mental and physical illness; however, the underlying neural mechanisms of mindfulness and how they relate to emotional processing have not been explored in depth. The current study used a within-subjects repeated measures design to examine if focused breathing, a brief mindfulness induction, could modulate event-related potentials (ERPs) during emotional image processing relative to a control condition. We related ERP measures of processing positive, negative, and neutral images (the P300 and late positive potential – LPP) to state and trait mindfulness measures. Overall, the brief mindfulness induction condition did not influence ERPs reflecting emotional processing; however, in the brief mindfulness induction condition, those participants who reported feeling more decentered (a subscale of the Toronto Mindfulness Scale) after viewing the images had reduced P300 responses to negative versus neutral images. PMID:26441766
a Critical Review of Automated Photogrammetric Processing of Large Datasets
NASA Astrophysics Data System (ADS)
Remondino, F.; Nocerino, E.; Toschi, I.; Menna, F.
2017-08-01
The paper reports some comparisons between commercial software able to automatically process image datasets for 3D reconstruction purposes. The main aspects investigated in the work are the capability to correctly orient large sets of image of complex environments, the metric quality of the results, replicability and redundancy. Different datasets are employed, each one featuring a diverse number of images, GSDs at cm and mm resolutions, and ground truth information to perform statistical analyses of the 3D results. A summary of (photogrammetric) terms is also provided, in order to provide rigorous terms of reference for comparisons and critical analyses.
Tracking prominent points in image sequences
NASA Astrophysics Data System (ADS)
Hahn, Michael
1994-03-01
Measuring image motion and inferring scene geometry and camera motion are main aspects of image sequence analysis. The determination of image motion and the structure-from-motion problem are tasks that can be addressed independently or in cooperative processes. In this paper we focus on tracking prominent points. High stability, reliability, and accuracy are criteria for the extraction of prominent points. This implies that tracking should work quite well with those features; unfortunately, the reality looks quite different. In the experimental investigations we processed a long sequence of 128 images. This mono sequence is taken in an outdoor environment at the experimental field of Mercedes Benz in Rastatt. Different tracking schemes are explored and the results with respect to stability and quality are reported.
Medical Image Analysis by Cognitive Information Systems - a Review.
Ogiela, Lidia; Takizawa, Makoto
2016-10-01
This publication presents a review of medical image analysis systems. The paradigms of cognitive information systems will be presented by examples of medical image analysis systems. The semantic processes present as it is applied to different types of medical images. Cognitive information systems were defined on the basis of methods for the semantic analysis and interpretation of information - medical images - applied to cognitive meaning of medical images contained in analyzed data sets. Semantic analysis was proposed to analyzed the meaning of data. Meaning is included in information, for example in medical images. Medical image analysis will be presented and discussed as they are applied to various types of medical images, presented selected human organs, with different pathologies. Those images were analyzed using different classes of cognitive information systems. Cognitive information systems dedicated to medical image analysis was also defined for the decision supporting tasks. This process is very important for example in diagnostic and therapy processes, in the selection of semantic aspects/features, from analyzed data sets. Those features allow to create a new way of analysis.
A quality-refinement process for medical imaging applications.
Neuhaus, J; Maleike, D; Nolden, M; Kenngott, H-G; Meinzer, H-P; Wolf, I
2009-01-01
To introduce and evaluate a process for refinement of software quality that is suitable to research groups. In order to avoid constraining researchers too much, the quality improvement process has to be designed carefully. The scope of this paper is to present and evaluate a process to advance quality aspects of existing research prototypes in order to make them ready for initial clinical studies. The proposed process is tailored for research environments and therefore more lightweight than traditional quality management processes. Focus on quality criteria that are important at the given stage of the software life cycle. Usage of tools that automate aspects of the process is emphasized. To evaluate the additional effort that comes along with the process, it was exemplarily applied for eight prototypical software modules for medical image processing. The introduced process has been applied to improve the quality of all prototypes so that they could be successfully used in clinical studies. The quality refinement yielded an average of 13 person days of additional effort per project. Overall, 107 bugs were found and resolved by applying the process. Careful selection of quality criteria and the usage of automated process tools lead to a lightweight quality refinement process suitable for scientific research groups that can be applied to ensure a successful transfer of technical software prototypes into clinical research workflows.
X-ray diffraction imaging (topography) of electroopticcrystals by synchrotron radiation
NASA Technical Reports Server (NTRS)
Steiner, Bruce; Kuriyama, Masao; Dobbyn, Ronald C.; Laor, Uri
1988-01-01
Information of special interest to crystal growers and device physicists now available from monochromatic synchrotron diffraction imaging (topography) is reviewed. Illustrations are taken from a variety of electro-optic crystals. Aspects of the detailed understanding of crystal growth processes obtainable from carefully selected samples are described. Finally, new experimental opportunities now available for exploitation are indicated.
Can Teachers' Images of Good Writing Conflict with Goals of Process Writing?
ERIC Educational Resources Information Center
McCarthey, Sarah J.
This paper explores the nature of a fifth/sixth grade New York City teacher's image of good writing, its effect on teacher-student interactions, and its influence on students. These three aspects are interwoven through a discussion of writing from personal experience, selecting a particular form for a specific audience, and including elements of…
The Aging Lung: Clinical and Imaging Findings and the Fringe of Physiological State.
Schröder, T H; Storbeck, B; Rabe, K F; Weber, C
2015-06-01
Since aspects of demographic transition have become an essential part of socioeconomic, medical and health-care research in the last decades, it is vital for the radiologist to discriminate between normal ageing related effects and abnormal imaging findings in the elderly. This article reviews functional and structural aspects of the ageing lung and focuses on typical ageing related radiological patterns. • The physiological aging process of the thoracic organs shows typical structural and functional aspects.• Mild interstitial fibrosis and focal parenchymal abnormalities like septal thickening can be diagnosed frequently - whereas a clinical correlate is often lacking.• With increasing patient age, the influence by various intrinsic and extrinsic factors (including comorbidities of the patient, and drug inhalation toxicants) also increases.• A growing spectrum of imaging techniques (including functional cardiopulmonary MRI, MRI spectroscopy, hybrid-techniques) is confronted by rare empiric data in the very old people (aging 80 years and older). © Georg Thieme Verlag KG Stuttgart · New York.
Image Registration Workshop Proceedings
NASA Technical Reports Server (NTRS)
LeMoigne, Jacqueline (Editor)
1997-01-01
Automatic image registration has often been considered as a preliminary step for higher-level processing, such as object recognition or data fusion. But with the unprecedented amounts of data which are being and will continue to be generated by newly developed sensors, the very topic of automatic image registration has become and important research topic. This workshop presents a collection of very high quality work which has been grouped in four main areas: (1) theoretical aspects of image registration; (2) applications to satellite imagery; (3) applications to medical imagery; and (4) image registration for computer vision research.
Neural network and its application to CT imaging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nikravesh, M.; Kovscek, A.R.; Patzek, T.W.
We present an integrated approach to imaging the progress of air displacement by spontaneous imbibition of oil into sandstone. We combine Computerized Tomography (CT) scanning and neural network image processing. The main aspects of our approach are (I) visualization of the distribution of oil and air saturation by CT, (II) interpretation of CT scans using neural networks, and (III) reconstruction of 3-D images of oil saturation from the CT scans with a neural network model. Excellent agreement between the actual images and the neural network predictions is found.
Smart sensor for terminal homing
NASA Astrophysics Data System (ADS)
Panda, D.; Aggarwal, R.; Hummel, R.
1980-01-01
The practical scene matching problem is considered to present certain complications which must extend classical image processing capabilities. Certain aspects of the scene matching problem which must be addressed by a smart sensor for terminal homing are discussed. First a philosophy for treating the matching problem for the terminal homing scenario is outlined. Then certain aspects of the feature extraction process and symbolic pattern matching are considered. It is thought that in the future general ideas from artificial intelligence will be more useful for terminal homing requirements of fast scene recognition and pattern matching.
Synthetic Aperture Imaging Polarimeter: Postprint
2010-02-01
mechanical design of the SAlP prototype revol .... es around the concept of a modular array. The modular aspect allows for the array to be built in...imagery of source . The top row images are of the actual fringe pattern incident on the SAlP prototype array. These pictures were taken through the...processed images associated with each of the inputs. The results demonstrated that the SAlP prototype array works in conjunction with the algorithm
A Review of Algorithms for Segmentation of Optical Coherence Tomography from Retina
Kafieh, Raheleh; Rabbani, Hossein; Kermani, Saeed
2013-01-01
Optical coherence tomography (OCT) is a recently established imaging technique to describe different information about the internal structures of an object and to image various aspects of biological tissues. OCT image segmentation is mostly introduced on retinal OCT to localize the intra-retinal boundaries. Here, we review some of the important image segmentation methods for processing retinal OCT images. We may classify the OCT segmentation approaches into five distinct groups according to the image domain subjected to the segmentation algorithm. Current researches in OCT segmentation are mostly based on improving the accuracy and precision, and on reducing the required processing time. There is no doubt that current 3-D imaging modalities are now moving the research projects toward volume segmentation along with 3-D rendering and visualization. It is also important to develop robust methods capable of dealing with pathologic cases in OCT imaging. PMID:24083137
Incoherent imaging of radar targets
NASA Astrophysics Data System (ADS)
van Ommen, A.; van der Spek, G. A.
1986-05-01
Theory suggests that, if a target can be modeled as a rigid constellation of point scatterers, the RCS pattern over a certain aspect change can be used to produce a one-dimensional image. The results for actual measured RCS patterns, however, are not promising. This is illustrated by processing on 4 s of echo data obtained from a Boeing 737 in straight flight, during which its aspect change is 2 deg. The conclusion might be that, for the application considered, aircraft cannot be modeled as a rigid constellation of point scatterers; this is partly due to the treatment of a three-dimensional target as a line target.
Methods and Materials for Selective Modification of Photopatterned Polymer Films.
1999-06-28
reactivity templates (see below) formed by patterned irradiation of polymer films. In particular, the invention describes binding materials and processes ...image of the attached functional group) or that region of the polymer film left unexposed and unchanged during the aforementioned patterning process ...invention are accomplished by the structures and processes hereinafter 15 described. An aspect of the present invention is a process for modifying a
Data path design and image quality aspects of the next generation multifunctional printer
NASA Astrophysics Data System (ADS)
Brassé, M. H. H.; de Smet, S. P. R. C.
2008-01-01
Multifunctional devices (MFDs) are increasingly used as a document hub. The MFD is used as a copier, scanner, printer, and it facilitates digital document distribution and sharing. This imposes new requirements on the design of the data path and its image processing. Various design aspects need to be taken into account, including system performance, features, image quality, and cost price. A good balance is required in order to develop a competitive MFD. A modular datapath architecture is presented that supports all the envisaged use cases. Besides copying, colour scanning is becoming an important use case of a modern MFD. The copy-path use case is described and it is shown how colour scanning can also be supported with a minimal adaptation to the architecture. The key idea is to convert the scanner data to an opponent colour space representation at the beginning of the image processing pipeline. The sub-sampling of chromatic information allows for the saving of scarce hardware resources without significant perceptual loss of quality. In particular, we have shown that functional FPGA modules from the copy application can also be used for the scan-to-file application. This makes the presented approach very cost-effective while complying with market conform image quality standards.
Accountability: A Mosaic Image
ERIC Educational Resources Information Center
Turner, Teri
1977-01-01
The problems involved in definition, implementation and control of accountability processes are discussed. It is stated that "...emotional involvement in accountability is one of the most difficult aspects to deal with, the chief emotion being fear". (Author/RW)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, E.L.
A novel method for performing real-time acquisition and processing Landsat/EROS data covers all aspects including radiometric and geometric corrections of multispectral scanner or return-beam vidicon inputs, image enhancement, statistical analysis, feature extraction, and classification. Radiometric transformations include bias/gain adjustment, noise suppression, calibration, scan angle compensation, and illumination compensation, including topography and atmospheric effects. Correction or compensation for geometric distortion includes sensor-related distortions, such as centering, skew, size, scan nonlinearity, radial symmetry, and tangential symmetry. Also included are object image-related distortions such as aspect angle (altitude), scale distortion (altitude), terrain relief, and earth curvature. Ephemeral corrections are also applied to compensatemore » for satellite forward movement, earth rotation, altitude variations, satellite vibration, and mirror scan velocity. Image enhancement includes high-pass, low-pass, and Laplacian mask filtering and data restoration for intermittent losses. Resource classification is provided by statistical analysis including histograms, correlational analysis, matrix manipulations, and determination of spectral responses. Feature extraction includes spatial frequency analysis, which is used in parallel discriminant functions in each array processor for rapid determination. The technique uses integrated parallel array processors that decimate the tasks concurrently under supervision of a control processor. The operator-machine interface is optimized for programming ease and graphics image windowing.« less
Real-time image processing for particle tracking velocimetry
NASA Astrophysics Data System (ADS)
Kreizer, Mark; Ratner, David; Liberzon, Alex
2010-01-01
We present a novel high-speed particle tracking velocimetry (PTV) experimental system. Its novelty is due to the FPGA-based, real-time image processing "on camera". Instead of an image, the camera transfers to the computer using a network card, only the relevant information of the identified flow tracers. Therefore, the system is ideal for the remote particle tracking systems in research and industrial applications, while the camera can be controlled and data can be transferred over any high-bandwidth network. We present the hardware and the open source software aspects of the PTV experiments. The tracking results of the new experimental system has been compared to the flow visualization and particle image velocimetry measurements. The canonical flow in the central cross section of a a cubic cavity (1:1:1 aspect ratio) in our lid-driven cavity apparatus is used for validation purposes. The downstream secondary eddy (DSE) is the sensitive portion of this flow and its size was measured with increasing Reynolds number (via increasing belt velocity). The size of DSE estimated from the flow visualization, PIV and compressed PTV is shown to agree within the experimental uncertainty of the methods applied.
Visually representing reality: aesthetics and accessibility aspects
NASA Astrophysics Data System (ADS)
van Nes, Floris L.
2009-02-01
This paper gives an overview of the visual representation of reality with three imaging technologies: painting, photography and electronic imaging. The contribution of the important image aspects, called dimensions hereafter, such as color, fine detail and total image size, to the degree of reality and aesthetic value of the rendered image are described for each of these technologies. Whereas quite a few of these dimensions - or approximations, or even only suggestions thereof - were already present in prehistoric paintings, apparent motion and true stereoscopic vision only recently were added - unfortunately also introducing accessibility and image safety issues. Efforts are made to reduce the incidence of undesirable biomedical effects such as photosensitive seizures (PSS), visually induced motion sickness (VIMS), and visual fatigue from stereoscopic images (VFSI) by international standardization of the image parameters to be avoided by image providers and display manufacturers. The history of this type of standardization, from an International Workshop Agreement to a strategy for accomplishing effective international standardization by ISO, is treated at some length. One of the difficulties to be mastered in this process is the reconciliation of the, sometimes opposing, interests of vulnerable persons, thrill-seeking viewers, creative video designers and the game industry.
Automatic Mosaicking of Satellite Imagery Considering the Clouds
NASA Astrophysics Data System (ADS)
Kang, Yifei; Pan, Li; Chen, Qi; Zhang, Tong; Zhang, Shasha; Liu, Zhang
2016-06-01
With the rapid development of high resolution remote sensing for earth observation technology, satellite imagery is widely used in the fields of resource investigation, environment protection, and agricultural research. Image mosaicking is an important part of satellite imagery production. However, the existence of clouds leads to lots of disadvantages for automatic image mosaicking, mainly in two aspects: 1) Image blurring may be caused during the process of image dodging, 2) Cloudy areas may be passed through by automatically generated seamlines. To address these problems, an automatic mosaicking method is proposed for cloudy satellite imagery in this paper. Firstly, modified Otsu thresholding and morphological processing are employed to extract cloudy areas and obtain the percentage of cloud cover. Then, cloud detection results are used to optimize the process of dodging and mosaicking. Thus, the mosaic image can be combined with more clear-sky areas instead of cloudy areas. Besides, clear-sky areas will be clear and distortionless. The Chinese GF-1 wide-field-of-view orthoimages are employed as experimental data. The performance of the proposed approach is evaluated in four aspects: the effect of cloud detection, the sharpness of clear-sky areas, the rationality of seamlines and efficiency. The evaluation results demonstrated that the mosaic image obtained by our method has fewer clouds, better internal color consistency and better visual clarity compared with that obtained by traditional method. The time consumed by the proposed method for 17 scenes of GF-1 orthoimages is within 4 hours on a desktop computer. The efficiency can meet the general production requirements for massive satellite imagery.
ERIC Educational Resources Information Center
Samson, Dana; Connolly, Catherine; Humphreys, Glyn W.
2007-01-01
The contribution of the left inferior prefrontal cortex in semantic processing has been widely investigated in the last decade. Converging evidence from functional imaging studies shows that this region is involved in the "executive" or "controlled" aspects of semantic processing. In this study, we report a single case study of a patient, PW, with…
Recht, Michael; Macari, Michael; Lawson, Kirk; Mulholland, Tom; Chen, David; Kim, Danny; Babb, James
2013-03-01
The aim of this study was to evaluate all aspects of workflow in a large academic MRI department to determine whether process improvement (PI) efforts could improve key performance indicators (KPIs). KPI metrics in the investigators' MR imaging department include daily inpatient backlogs, on-time performance for outpatient examinations, examination volumes, appointment backlogs for pediatric anesthesia cases, and scan duration relative to time allotted for an examination. Over a 3-week period in April 2011, key members of the MR imaging department (including technologists, nurses, schedulers, physicians, and administrators) tracked all aspects of patient flow through the department, from scheduling to examination interpretation. Data were analyzed by the group to determine where PI could improve KPIs. Changes to MRI workflow were subsequently implemented, and KPIs were compared before (January 1, 2011, to April 30, 2011) and after (August 1, 2011, to December 31, 2011) using Mann-Whitney and Fisher's exact tests. The data analysis done during this PI led to multiple changes in the daily workflow of the MR department. In addition, a new sense of teamwork and empowerment was established within the MR staff. All of the measured KPIs showed statistically significant changes after the reengineering project. Intradepartmental PI efforts can significantly affect KPI metrics within an MR imaging department, making the process more patient centered. In addition, the process allowed significant growth without the need for additional equipment or personnel. Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.
A novel weighted-direction color interpolation
NASA Astrophysics Data System (ADS)
Tao, Jin-you; Yang, Jianfeng; Xue, Bin; Liang, Xiaofen; Qi, Yong-hong; Wang, Feng
2013-08-01
A digital camera capture images by covering the sensor surface with a color filter array (CFA), only get a color sample at pixel location. Demosaicking is a process by estimating the missing color components of each pixel to get a full resolution image. In this paper, a new algorithm based on edge adaptive and different weighting factors is proposed. Our method can effectively suppress undesirable artifacts. Experimental results based on Kodak images show that the proposed algorithm obtain higher quality images compared to other methods in numerical and visual aspects.
Experiments with recursive estimation in astronomical image processing
NASA Technical Reports Server (NTRS)
Busko, I.
1992-01-01
Recursive estimation concepts were applied to image enhancement problems since the 70's. However, very few applications in the particular area of astronomical image processing are known. These concepts were derived, for 2-dimensional images, from the well-known theory of Kalman filtering in one dimension. The historic reasons for application of these techniques to digital images are related to the images' scanned nature, in which the temporal output of a scanner device can be processed on-line by techniques borrowed directly from 1-dimensional recursive signal analysis. However, recursive estimation has particular properties that make it attractive even in modern days, when big computer memories make the full scanned image available to the processor at any given time. One particularly important aspect is the ability of recursive techniques to deal with non-stationary phenomena, that is, phenomena which have their statistical properties variable in time (or position in a 2-D image). Many image processing methods make underlying stationary assumptions either for the stochastic field being imaged, for the imaging system properties, or both. They will underperform, or even fail, when applied to images that deviate significantly from stationarity. Recursive methods, on the contrary, make it feasible to perform adaptive processing, that is, to process the image by a processor with properties tuned to the image's local statistical properties. Recursive estimation can be used to build estimates of images degraded by such phenomena as noise and blur. We show examples of recursive adaptive processing of astronomical images, using several local statistical properties to drive the adaptive processor, as average signal intensity, signal-to-noise and autocorrelation function. Software was developed under IRAF, and as such will be made available to interested users.
Modeling, simulation, and analysis of optical remote sensing systems
NASA Technical Reports Server (NTRS)
Kerekes, John Paul; Landgrebe, David A.
1989-01-01
Remote Sensing of the Earth's resources from space-based sensors has evolved in the past 20 years from a scientific experiment to a commonly used technological tool. The scientific applications and engineering aspects of remote sensing systems have been studied extensively. However, most of these studies have been aimed at understanding individual aspects of the remote sensing process while relatively few have studied their interrelations. A motivation for studying these interrelationships has arisen with the advent of highly sophisticated configurable sensors as part of the Earth Observing System (EOS) proposed by NASA for the 1990's. Two approaches to investigating remote sensing systems are developed. In one approach, detailed models of the scene, the sensor, and the processing aspects of the system are implemented in a discrete simulation. This approach is useful in creating simulated images with desired characteristics for use in sensor or processing algorithm development. A less complete, but computationally simpler method based on a parametric model of the system is also developed. In this analytical model the various informational classes are parameterized by their spectral mean vector and covariance matrix. These class statistics are modified by models for the atmosphere, the sensor, and processing algorithms and an estimate made of the resulting classification accuracy among the informational classes. Application of these models is made to the study of the proposed High Resolution Imaging Spectrometer (HRIS). The interrelationships among observational conditions, sensor effects, and processing choices are investigated with several interesting results.
Development of CCD imaging sensors for space applications, phase 1
NASA Technical Reports Server (NTRS)
Antcliffe, G. A.
1975-01-01
The results of an experimental investigation to develop a large area charge coupled device (CCD) imager for space photography applications are described. Details of the design and processing required to achieve 400 X 400 imagers are presented together with a discussion of the optical characterization techniques developed for this program. A discussion of several aspects of large CCD performance is given with detailed test reports. The areas covered include dark current, uniformity of optical response, square wave amplitude response, spectral responsivity and dynamic range.
Restoration of color in a remote sensing image and its quality evaluation
NASA Astrophysics Data System (ADS)
Zhang, Zuxun; Li, Zhijiang; Zhang, Jianqing; Wang, Zhihe
2003-09-01
This paper is focused on the restoration of color remote sensing (including airborne photo). A complete approach is recommended. It propose that two main aspects should be concerned in restoring a remote sensing image, that are restoration of space information, restoration of photometric information. In this proposal, the restoration of space information can be performed by making the modulation transfer function (MTF) as degradation function, in which the MTF is obtained by measuring the edge curve of origin image. The restoration of photometric information can be performed by improved local maximum entropy algorithm. What's more, a valid approach in processing color remote sensing image is recommended. That is splits the color remote sensing image into three monochromatic images which corresponding three visible light bands and synthesizes the three images after being processed separately with psychological color vision restriction. Finally, three novel evaluation variables are obtained based on image restoration to evaluate the image restoration quality in space restoration quality and photometric restoration quality. An evaluation is provided at last.
Karimi, Davood; Ward, Rabab K
2016-10-01
Image models are central to all image processing tasks. The great advancements in digital image processing would not have been made possible without powerful models which, themselves, have evolved over time. In the past decade, "patch-based" models have emerged as one of the most effective models for natural images. Patch-based methods have outperformed other competing methods in many image processing tasks. These developments have come at a time when greater availability of powerful computational resources and growing concerns over the health risks of the ionizing radiation encourage research on image processing algorithms for computed tomography (CT). The goal of this paper is to explain the principles of patch-based methods and to review some of their recent applications in CT. We first review the central concepts in patch-based image processing and explain some of the state-of-the-art algorithms, with a focus on aspects that are more relevant to CT. Then, we review some of the recent application of patch-based methods in CT. Patch-based methods have already transformed the field of image processing, leading to state-of-the-art results in many applications. More recently, several studies have proposed patch-based algorithms for various image processing tasks in CT, from denoising and restoration to iterative reconstruction. Although these studies have reported good results, the true potential of patch-based methods for CT has not been yet appreciated. Patch-based methods can play a central role in image reconstruction and processing for CT. They have the potential to lead to substantial improvements in the current state of the art.
The Process of Coorientation Toward a Definition of the Situation.
ERIC Educational Resources Information Center
Craig, Robert; And Others
The concept of definition of the situation is rooted in the view that human behavior is affected by the environment only indirectly, via the person's image or cognitive map. As a communication concept, however, definition of the situation must also have a relational aspect; an interaction process depends, in part, on the relationship between the…
Zimmer, H D
1993-01-01
It is discussed what is underlying the assumption of modality-specific processing systems and representations. Starting from the information processing approach relevant aspects of mental representations and their physiological realizations are discussed. Then three different forms of modality-specific systems are distinguished: as stimulus specific processing, as specific informational formats, and as modular part systems. Parallel to that three kinds of analogue systems are differentiated: as holding an analogue-relation, as having a specific informational format and as a set of specific processing constraints. These different aspects of the assumption of modality-specific systems are demonstrated in the example of visual and spatial information processing. It is concluded that postulating information-specific systems is not a superfluous assumption, but it is necessary, and even more likely it is an inevitable consequence of an optimization of stimulus processing.
UWGSP4: an imaging and graphics superworkstation and its medical applications
NASA Astrophysics Data System (ADS)
Jong, Jing-Ming; Park, Hyun Wook; Eo, Kilsu; Kim, Min-Hwan; Zhang, Peng; Kim, Yongmin
1992-05-01
UWGSP4 is configured with a parallel architecture for image processing and a pipelined architecture for computer graphics. The system's peak performance is 1,280 MFLOPS for image processing and over 200,000 Gouraud shaded 3-D polygons per second for graphics. The simulated sustained performance is about 50% of the peak performance in general image processing. Most of the 2-D image processing functions are efficiently vectorized and parallelized in UWGSP4. A performance of 770 MFLOPS in convolution and 440 MFLOPS in FFT is achieved. The real-time cine display, up to 32 frames of 1280 X 1024 pixels per second, is supported. In 3-D imaging, the update rate for the surface rendering is 10 frames of 20,000 polygons per second; the update rate for the volume rendering is 6 frames of 128 X 128 X 128 voxels per second. The system provides 1280 X 1024 X 32-bit double frame buffers and one 1280 X 1024 X 8-bit overlay buffer for supporting realistic animation, 24-bit true color, and text annotation. A 1280 X 1024- pixel, 66-Hz noninterlaced display screen with 1:1 aspect ratio can be windowed into the frame buffer for the display of any portion of the processed image or graphics.
Imaging Alzheimer's disease pathophysiology with PET
Schilling, Lucas Porcello; Zimmer, Eduardo R.; Shin, Monica; Leuzy, Antoine; Pascoal, Tharick A.; Benedet, Andréa L.; Borelli, Wyllians Vendramini; Palmini, André; Gauthier, Serge; Rosa-Neto, Pedro
2016-01-01
ABSTRACT Alzheimer's disease (AD) has been reconceptualised as a dynamic pathophysiological process characterized by preclinical, mild cognitive impairment (MCI), and dementia stages. Positron emission tomography (PET) associated with various molecular imaging agents reveals numerous aspects of dementia pathophysiology, such as brain amyloidosis, tau accumulation, neuroreceptor changes, metabolism abnormalities and neuroinflammation in dementia patients. In the context of a growing shift toward presymptomatic early diagnosis and disease-modifying interventions, PET molecular imaging agents provide an unprecedented means of quantifying the AD pathophysiological process, monitoring disease progression, ascertaining whether therapies engage their respective brain molecular targets, as well as quantifying pharmacological responses. In the present study, we highlight the most important contributions of PET in describing brain molecular abnormalities in AD. PMID:29213438
Image reproduction with interactive graphics
NASA Technical Reports Server (NTRS)
Buckner, J. D.; Council, H. W.; Edwards, T. R.
1974-01-01
Software application or development in optical image digital data processing requires a fast, good quality, yet inexpensive hard copy of processed images. To achieve this, a Cambo camera with an f 2.8/150-mm Xenotar lens in a Copal shutter having a Graflok back for 4 x 5 Polaroid type 57 pack-film has been interfaced to an existing Adage, AGT-30/Electro-Mechanical Research, EMR 6050 graphic computer system. Time-lapse photography in conjunction with a log to linear voltage transformation has resulted in an interactive system capable of producing a hard copy in 54 sec. The interactive aspect of the system lies in a Tektronix 4002 graphic computer terminal and its associated hard copy unit.
Microtomographic imaging in the process of bone modeling and simulation
NASA Astrophysics Data System (ADS)
Mueller, Ralph
1999-09-01
Micro-computed tomography ((mu) CT) is an emerging technique to nondestructively image and quantify trabecular bone in three dimensions. Where the early implementations of (mu) CT focused more on technical aspects of the systems and required equipment not normally available to the general public, a more recent development emphasized practical aspects of micro- tomographic imaging. That system is based on a compact fan- beam type of tomograph, also referred to as desktop (mu) CT. Desk-top (mu) CT has been used extensively for the investigation of osteoporosis related health problems gaining new insight into the organization of trabecular bone and the influence of osteoporotic bone loss on bone architecture and the competence of bone. Osteoporosis is a condition characterized by excessive bone loss and deterioration in bone architecture. The reduced quality of bone increases the risk of fracture. Current imaging technologies do not allow accurate in vivo measurements of bone structure over several decades or the investigation of the local remodeling stimuli at the tissue level. Therefore, computer simulations and new experimental modeling procedures are necessary for determining the long-term effects of age, menopause, and osteoporosis on bone. Microstructural bone models allow us to study not only the effects of osteoporosis on the skeleton but also to assess and monitor the effectiveness of new treatment regimens. The basis for such approaches are realistic models of bone and a sound understanding of the underlying biological and mechanical processes in bone physiology. In this article, strategies for new approaches to bone modeling and simulation in the study and treatment of osteoporosis and age-related bone loss are presented. The focus is on the bioengineering and imaging aspects of osteoporosis research. With the introduction of desk-top (mu) CT, a new generation of imaging instruments has entered the arena allowing easy and relatively inexpensive access to the three-dimensional microstructure of bone, thereby giving bone researchers a powerful tool for the exploration of age-related bone loss and osteoporosis.
Segregating the core computational faculty of human language from working memory.
Makuuchi, Michiru; Bahlmann, Jörg; Anwander, Alfred; Friederici, Angela D
2009-05-19
In contrast to simple structures in animal vocal behavior, hierarchical structures such as center-embedded sentences manifest the core computational faculty of human language. Previous artificial grammar learning studies found that the left pars opercularis (LPO) subserves the processing of hierarchical structures. However, it is not clear whether this area is activated by the structural complexity per se or by the increased memory load entailed in processing hierarchical structures. To dissociate the effect of structural complexity from the effect of memory cost, we conducted a functional magnetic resonance imaging study of German sentence processing with a 2-way factorial design tapping structural complexity (with/without hierarchical structure, i.e., center-embedding of clauses) and working memory load (long/short distance between syntactically dependent elements; i.e., subject nouns and their respective verbs). Functional imaging data revealed that the processes for structure and memory operate separately but co-operatively in the left inferior frontal gyrus; activities in the LPO increased as a function of structural complexity, whereas activities in the left inferior frontal sulcus (LIFS) were modulated by the distance over which the syntactic information had to be transferred. Diffusion tensor imaging showed that these 2 regions were interconnected through white matter fibers. Moreover, functional coupling between the 2 regions was found to increase during the processing of complex, hierarchically structured sentences. These results suggest a neuroanatomical segregation of syntax-related aspects represented in the LPO from memory-related aspects reflected in the LIFS, which are, however, highly interconnected functionally and anatomically.
Amestoy, Anouck; Bouvard, Manuel P; Cazalets, Jean-René
2010-01-01
We investigated the developmental aspect of sensitivity to the orientation of familiar faces by asking 38 adults and 72 children from 3 to 12 years old to make a preference choice between standard and mirror images of themselves and of familiar faces, presented side-by-side or successively. When familiar (parental) faces were presented simultaneously, 3- to 5-year-olds showed no preference, but by age 5-7 years an adult-like preference for the standard image emerged. Similarly, the adult-like preference for the mirror image of their own face emerged by 5-7 years of age. When familiar or self faces were presented successively, 3- to 7-year-olds showed no preference, and adult-like preference for the standard image emerged by age 7-12 years. These results suggest the occurrence of a developmental process in the perception of familiar face asymmetries which is retained in memory related to knowledge about faces.
Sujlana, Parvinder; Skrok, Jan; Fayad, Laura M
2018-04-01
Although postcontrast imaging has been used for many years in musculoskeletal imaging, dynamic contrast enhanced (DCE) MRI is not routinely used in many centers around the world. Unlike conventional contrast-enhanced sequences, DCE-MRI allows the evaluation of the temporal pattern of enhancement in the musculoskeletal system, perhaps best known for its use in oncologic applications (such as differentiating benign from malignant tumors, evaluating for treatment response after neoadjuvant chemotherapy, and differentiating postsurgical changes from residual tumor). However, DCE-MRI can also be used to evaluate inflammatory processes such as Charcot foot and synovitis, and evaluate bone perfusion in entities like Legg Calve Perthes disease and arthritis. Finally, vascular abnormalities and associated complications may be better characterized with DCE-MRI than conventional imaging. The goal of this article is to review the applications and technical aspects of DCE-MRI in the musculoskeletal system. 5 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:875-890. © 2017 International Society for Magnetic Resonance in Medicine.
Image denoising based on noise detection
NASA Astrophysics Data System (ADS)
Jiang, Yuanxiang; Yuan, Rui; Sun, Yuqiu; Tian, Jinwen
2018-03-01
Because of the noise points in the images, any operation of denoising would change the original information of non-noise pixel. A noise detection algorithm based on fractional calculus was proposed to denoise in this paper. Convolution of the image was made to gain direction gradient masks firstly. Then, the mean gray was calculated to obtain the gradient detection maps. Logical product was made to acquire noise position image next. Comparisons in the visual effect and evaluation parameters after processing, the results of experiment showed that the denoising algorithms based on noise were better than that of traditional methods in both subjective and objective aspects.
The influence of software filtering in digital mammography image quality
NASA Astrophysics Data System (ADS)
Michail, C.; Spyropoulou, V.; Kalyvas, N.; Valais, I.; Dimitropoulos, N.; Fountos, G.; Kandarakis, I.; Panayiotakis, G.
2009-05-01
Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.
Glover, Gary H.; Mueller, Bryon A.; Turner, Jessica A.; van Erp, Theo G.M.; Liu, Thomas T.; Greve, Douglas N.; Voyvodic, James T.; Rasmussen, Jerod; Brown, Gregory G.; Keator, David B.; Calhoun, Vince D.; Lee, Hyo Jong; Ford, Judith M.; Mathalon, Daniel H.; Diaz, Michele; O’Leary, Daniel S.; Gadde, Syam; Preda, Adrian; Lim, Kelvin O.; Wible, Cynthia G.; Stern, Hal S.; Belger, Aysenil; McCarthy, Gregory; Ozyurt, Burak; Potkin, Steven G.
2011-01-01
This report provides practical recommendations for the design and execution of Multi-Center functional Magnetic Resonance Imaging (MC-fMRI) studies based on the collective experience of the Function Biomedical Informatics Research Network (FBIRN). The paper was inspired by many requests from the fMRI community to FBIRN group members for advice on how to conduct MC-fMRI studies. The introduction briefly discusses the advantages and complexities of MC-fMRI studies. Prerequisites for MC-fMRI studies are addressed before delving into the practical aspects of carefully and efficiently setting up a MC-fMRI study. Practical multi-site aspects include: (1) establishing and verifying scan parameters including scanner types and magnetic fields, (2) establishing and monitoring of a scanner quality program, (3) developing task paradigms and scan session documentation, (4) establishing clinical and scanner training to ensure consistency over time, (5) developing means for uploading, storing, and monitoring of imaging and other data, (6) the use of a traveling fMRI expert and (7) collectively analyzing imaging data and disseminating results. We conclude that when MC-fMRI studies are organized well with careful attention to unification of hardware, software and procedural aspects, the process can be a highly effective means for accessing a desired participant demographics while accelerating scientific discovery. PMID:22314879
The AAO fiber instrument data simulator
NASA Astrophysics Data System (ADS)
Goodwin, Michael; Farrell, Tony; Smedley, Scott; Heald, Ron; Heijmans, Jeroen; De Silva, Gayandhi; Carollo, Daniela
2012-09-01
The fiber instrument data simulator is an in-house software tool that simulates detector images of fiber-fed spectrographs developed by the Australian Astronomical Observatory (AAO). In addition to helping validate the instrument designs, the resulting simulated images are used to develop the required data reduction software. Example applications that have benefited from the tool usage are the HERMES and SAMI instrumental projects for the Anglo-Australian Telescope (AAT). Given the sophistication of these projects an end-to-end data simulator that accurately models the predicted detector images is required. The data simulator encompasses all aspects of the transmission and optical aberrations of the light path: from the science object, through the atmosphere, telescope, fibers, spectrograph and finally the camera detectors. The simulator runs under a Linux environment that uses pre-calculated information derived from ZEMAX models and processed data from MATLAB. In this paper, we discuss the aspects of the model, software, example simulations and verification.
NASA Astrophysics Data System (ADS)
Zhang, Ding; Han, Xiaoyan; Newaz, Golam; Favro, Lawrence D.; Thomas, Robert L.
2013-01-01
We showed our work on modeling turbine blade crack detection in Sonic Infrared (IR) Imaging with a method of creating flat crack surface in finite element analysis (FEA) in last year's QNDE paper. This modeling has been carried out continuously as part of model-assisted study on crack detection in aircraft engine turbine blades. We have presented that Sonic IR Imaging NDE is a viable method to detect defects in various structures. It combines ultrasound excitation for frictional heating in defects and infrared imaging to sense this heating, and thus to identify the defects. It is a fast wide-area imaging technology. It only takes a second to image a large area of a target sample. When an aircraft is in flight, the turbine engine blades operate under high temperature and high cyclic stresses. Thus, fatigue cracks can form after many hours of operation. Sonic IR Imaging can be used to detect such cracks. However, we still need to better understand contributions of parameters/factors in the crack detection process with Sonic IR Imaging. FEA modeling can help us to reveal certain aspects through the data it produces where experimental work cannot achieve. Upon the model we presented last year, a two-step simulation process was designed to simulate the important aspects in our experiments. These include a newly designed model for the ultrasound transducer which delivers mechanical energy to the sample and the implementation of static force while engaging the transducer to the sample. In this paper, we present the ideas and the results from the new model.
FluoroSim: A Visual Problem-Solving Environment for Fluorescence Microscopy
Quammen, Cory W.; Richardson, Alvin C.; Haase, Julian; Harrison, Benjamin D.; Taylor, Russell M.; Bloom, Kerry S.
2010-01-01
Fluorescence microscopy provides a powerful method for localization of structures in biological specimens. However, aspects of the image formation process such as noise and blur from the microscope's point-spread function combine to produce an unintuitive image transformation on the true structure of the fluorescing molecules in the specimen, hindering qualitative and quantitative analysis of even simple structures in unprocessed images. We introduce FluoroSim, an interactive fluorescence microscope simulator that can be used to train scientists who use fluorescence microscopy to understand the artifacts that arise from the image formation process, to determine the appropriateness of fluorescence microscopy as an imaging modality in an experiment, and to test and refine hypotheses of model specimens by comparing the output of the simulator to experimental data. FluoroSim renders synthetic fluorescence images from arbitrary geometric models represented as triangle meshes. We describe three rendering algorithms on graphics processing units for computing the convolution of the specimen model with a microscope's point-spread function and report on their performance. We also discuss several cases where the microscope simulator has been used to solve real problems in biology. PMID:20431698
Efficiency analysis for 3D filtering of multichannel images
NASA Astrophysics Data System (ADS)
Kozhemiakin, Ruslan A.; Rubel, Oleksii; Abramov, Sergey K.; Lukin, Vladimir V.; Vozel, Benoit; Chehdi, Kacem
2016-10-01
Modern remote sensing systems basically acquire images that are multichannel (dual- or multi-polarization, multi- and hyperspectral) where noise, usually with different characteristics, is present in all components. If noise is intensive, it is desirable to remove (suppress) it before applying methods of image classification, interpreting, and information extraction. This can be done using one of two approaches - by component-wise or by vectorial (3D) filtering. The second approach has shown itself to have higher efficiency if there is essential correlation between multichannel image components as this often happens for multichannel remote sensing data of different origin. Within the class of 3D filtering techniques, there are many possibilities and variations. In this paper, we consider filtering based on discrete cosine transform (DCT) and pay attention to two aspects of processing. First, we study in detail what changes in DCT coefficient statistics take place for 3D denoising compared to component-wise processing. Second, we analyze how selection of component images united into 3D data array influences efficiency of filtering and can the observed tendencies be exploited in processing of images with rather large number of channels.
IEEE International Symposium on Biomedical Imaging.
2017-01-01
The IEEE International Symposium on Biomedical Imaging (ISBI) is a scientific conference dedicated to mathematical, algorithmic, and computational aspects of biological and biomedical imaging, across all scales of observation. It fosters knowledge transfer among different imaging communities and contributes to an integrative approach to biomedical imaging. ISBI is a joint initiative from the IEEE Signal Processing Society (SPS) and the IEEE Engineering in Medicine and Biology Society (EMBS). The 2018 meeting will include tutorials, and a scientific program composed of plenary talks, invited special sessions, challenges, as well as oral and poster presentations of peer-reviewed papers. High-quality papers are requested containing original contributions to the topics of interest including image formation and reconstruction, computational and statistical image processing and analysis, dynamic imaging, visualization, image quality assessment, and physical, biological, and statistical modeling. Accepted 4-page regular papers will be published in the symposium proceedings published by IEEE and included in IEEE Xplore. To encourage attendance by a broader audience of imaging scientists and offer additional presentation opportunities, ISBI 2018 will continue to have a second track featuring posters selected from 1-page abstract submissions without subsequent archival publication.
York, Timothy; Powell, Samuel B.; Gao, Shengkui; Kahan, Lindsey; Charanya, Tauseef; Saha, Debajit; Roberts, Nicholas W.; Cronin, Thomas W.; Marshall, Justin; Achilefu, Samuel; Lake, Spencer P.; Raman, Baranidharan; Gruev, Viktor
2015-01-01
In this paper, we present recent work on bioinspired polarization imaging sensors and their applications in biomedicine. In particular, we focus on three different aspects of these sensors. First, we describe the electro–optical challenges in realizing a bioinspired polarization imager, and in particular, we provide a detailed description of a recent low-power complementary metal–oxide–semiconductor (CMOS) polarization imager. Second, we focus on signal processing algorithms tailored for this new class of bioinspired polarization imaging sensors, such as calibration and interpolation. Third, the emergence of these sensors has enabled rapid progress in characterizing polarization signals and environmental parameters in nature, as well as several biomedical areas, such as label-free optical neural recording, dynamic tissue strength analysis, and early diagnosis of flat cancerous lesions in a murine colorectal tumor model. We highlight results obtained from these three areas and discuss future applications for these sensors. PMID:26538682
Efficient HIK SVM learning for image classification.
Wu, Jianxin
2012-10-01
Histograms are used in almost every aspect of image processing and computer vision, from visual descriptors to image representations. Histogram intersection kernel (HIK) and support vector machine (SVM) classifiers are shown to be very effective in dealing with histograms. This paper presents contributions concerning HIK SVM for image classification. First, we propose intersection coordinate descent (ICD), a deterministic and scalable HIK SVM solver. ICD is much faster than, and has similar accuracies to, general purpose SVM solvers and other fast HIK SVM training methods. We also extend ICD to the efficient training of a broader family of kernels. Second, we show an important empirical observation that ICD is not sensitive to the C parameter in SVM, and we provide some theoretical analyses to explain this observation. ICD achieves high accuracies in many problems, using its default parameters. This is an attractive property for practitioners, because many image processing tasks are too large to choose SVM parameters using cross-validation.
2008-11-01
17ºC; red: 17-18ºC. Although the image produced in Figure 9 is useful, the image itself is not the most important aspect of the process . Two...climatology for the Scotian Shelf. The database is intended for use while ashore and also while at-sea. Trial Q316 was the maiden voyage of the database...to the process of data transfer from external sources to the database, and also how the database can be restructured to be more accommodating of
Ink-constrained halftoning with application to QR codes
NASA Astrophysics Data System (ADS)
Bayeh, Marzieh; Compaan, Erin; Lindsey, Theodore; Orlow, Nathan; Melczer, Stephen; Voller, Zachary
2014-01-01
This paper examines adding visually significant, human recognizable data into QR codes without affecting their machine readability by utilizing known methods in image processing. Each module of a given QR code is broken down into pixels, which are halftoned in such a way as to keep the QR code structure while revealing aspects of the secondary image to the human eye. The loss of information associated to this procedure is discussed, and entropy values are calculated for examples given in the paper. Numerous examples of QR codes with embedded images are included.
Ahn, Hye Shin; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young
2014-01-01
To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.
ERIC Educational Resources Information Center
Legenbauer, Tanja; Vocks, Silja; Betz, Sabrina; Puigcerver, Maria Jose Baguena; Benecke, Andrea; Troje, Nikolaus F.; Ruddel, Heinz
2011-01-01
Various components of body image were measured to assess body image disturbances in patients with obesity. To overcome limitations of previous studies, a photo distortion technique and a biological motion distortion device were included to assess static and dynamic aspects of body image. Questionnaires assessed cognitive-affective aspects, bodily…
High-performance computing in image registration
NASA Astrophysics Data System (ADS)
Zanin, Michele; Remondino, Fabio; Dalla Mura, Mauro
2012-10-01
Thanks to the recent technological advances, a large variety of image data is at our disposal with variable geometric, radiometric and temporal resolution. In many applications the processing of such images needs high performance computing techniques in order to deliver timely responses e.g. for rapid decisions or real-time actions. Thus, parallel or distributed computing methods, Digital Signal Processor (DSP) architectures, Graphical Processing Unit (GPU) programming and Field-Programmable Gate Array (FPGA) devices have become essential tools for the challenging issue of processing large amount of geo-data. The article focuses on the processing and registration of large datasets of terrestrial and aerial images for 3D reconstruction, diagnostic purposes and monitoring of the environment. For the image alignment procedure, sets of corresponding feature points need to be automatically extracted in order to successively compute the geometric transformation that aligns the data. The feature extraction and matching are ones of the most computationally demanding operations in the processing chain thus, a great degree of automation and speed is mandatory. The details of the implemented operations (named LARES) exploiting parallel architectures and GPU are thus presented. The innovative aspects of the implementation are (i) the effectiveness on a large variety of unorganized and complex datasets, (ii) capability to work with high-resolution images and (iii) the speed of the computations. Examples and comparisons with standard CPU processing are also reported and commented.
Planning to avoid trouble in the operating room: experts' formulation of the preoperative plan.
Zilbert, Nathan R; St-Martin, Laurent; Regehr, Glenn; Gallinger, Steven; Moulton, Carol-Anne
2015-01-01
The purpose of this study was to capture the preoperative plans of expert hepato-pancreato-biliary (HPB) surgeons with the goal of finding consistent aspects of the preoperative planning process. HPB surgeons were asked to think aloud when reviewing 4 preoperative computed tomography scans of patients with distal pancreatic tumors. The imaging features they identified and the planned actions they proposed were tabulated. Surgeons viewed the tabulated list of imaging features for each case and rated the relevance of each feature for their subsequent preoperative plan. Average rater intraclass correlation coefficients were calculated for each type of data collected (imaging features detected, planned actions reported, and relevance of each feature) to establish whether the surgeons were consistent with one another in their responses. Average rater intraclass correlation coefficient values greater than 0.7 were considered indicative of consistency. Division of General Surgery, University of Toronto. HPB surgeons affiliated with the University of Toronto. A total of 11 HPB surgeons thought aloud when reviewing 4 computed tomography scans. Surgeons were consistent in the imaging features they detected but inconsistent in the planned actions they reported. Of the HPB surgeons, 8 completed the assessment of feature relevance. For 3 of the 4 cases, the surgeons were consistent in rating the relevance of specific imaging features on their preoperative plans. These results suggest that HPB surgeons are consistent in some aspects of the preoperative planning process but not others. The findings further our understanding of the preoperative planning process and will guide future research on the best ways to incorporate the teaching and evaluation of preoperative planning into surgical training. Copyright © 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Survey: interpolation methods for whole slide image processing.
Roszkowiak, L; Korzynska, A; Zak, J; Pijanowska, D; Swiderska-Chadaj, Z; Markiewicz, T
2017-02-01
Evaluating whole slide images of histological and cytological samples is used in pathology for diagnostics, grading and prognosis . It is often necessary to rescale whole slide images of a very large size. Image resizing is one of the most common applications of interpolation. We collect the advantages and drawbacks of nine interpolation methods, and as a result of our analysis, we try to select one interpolation method as the preferred solution. To compare the performance of interpolation methods, test images were scaled and then rescaled to the original size using the same algorithm. The modified image was compared to the original image in various aspects. The time needed for calculations and results of quantification performance on modified images were also compared. For evaluation purposes, we used four general test images and 12 specialized biological immunohistochemically stained tissue sample images. The purpose of this survey is to determine which method of interpolation is the best to resize whole slide images, so they can be further processed using quantification methods. As a result, the interpolation method has to be selected depending on the task involving whole slide images. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.
The infection algorithm: an artificial epidemic approach for dense stereo correspondence.
Olague, Gustavo; Fernández, Francisco; Pérez, Cynthia B; Lutton, Evelyne
2006-01-01
We present a new bio-inspired approach applied to a problem of stereo image matching. This approach is based on an artificial epidemic process, which we call the infection algorithm. The problem at hand is a basic one in computer vision for 3D scene reconstruction. It has many complex aspects and is known as an extremely difficult one. The aim is to match the contents of two images in order to obtain 3D information that allows the generation of simulated projections from a viewpoint that is different from the ones of the initial photographs. This process is known as view synthesis. The algorithm we propose exploits the image contents in order to produce only the necessary 3D depth information, while saving computational time. It is based on a set of distributed rules, which propagate like an artificial epidemic over the images. Experiments on a pair of real images are presented, and realistic reprojected images have been generated.
Segregating the core computational faculty of human language from working memory
Makuuchi, Michiru; Bahlmann, Jörg; Anwander, Alfred; Friederici, Angela D.
2009-01-01
In contrast to simple structures in animal vocal behavior, hierarchical structures such as center-embedded sentences manifest the core computational faculty of human language. Previous artificial grammar learning studies found that the left pars opercularis (LPO) subserves the processing of hierarchical structures. However, it is not clear whether this area is activated by the structural complexity per se or by the increased memory load entailed in processing hierarchical structures. To dissociate the effect of structural complexity from the effect of memory cost, we conducted a functional magnetic resonance imaging study of German sentence processing with a 2-way factorial design tapping structural complexity (with/without hierarchical structure, i.e., center-embedding of clauses) and working memory load (long/short distance between syntactically dependent elements; i.e., subject nouns and their respective verbs). Functional imaging data revealed that the processes for structure and memory operate separately but co-operatively in the left inferior frontal gyrus; activities in the LPO increased as a function of structural complexity, whereas activities in the left inferior frontal sulcus (LIFS) were modulated by the distance over which the syntactic information had to be transferred. Diffusion tensor imaging showed that these 2 regions were interconnected through white matter fibers. Moreover, functional coupling between the 2 regions was found to increase during the processing of complex, hierarchically structured sentences. These results suggest a neuroanatomical segregation of syntax-related aspects represented in the LPO from memory-related aspects reflected in the LIFS, which are, however, highly interconnected functionally and anatomically. PMID:19416819
ERIC Educational Resources Information Center
Young, Bernard
2012-01-01
Photography students spend a considerable amount of time working on technical issues in shooting, composing, editing, and processing prints. Another aspect of their learning should include the conception and communication of their ideas. A student's memories and dreams can serve as motivation to create images in visual art. Some artists claim that…
NASA Astrophysics Data System (ADS)
Mu, Yue; Wang, Feng; Zheng, Bangyou; Guo, Wei; Feng, Yiming
2018-03-01
The relationship between morphological characteristics (e.g. gravel size, coverage, angularity and orientation) and local geomorphic features (e.g. slope gradient and aspect) of desert has been used to explore the evolution process of Gobi desert. Conventional quantification methods are time-consuming, inefficient and even prove impossible to determine the characteristics of large numbers of gravels. We propose a rapid image-based method to obtain the morphological characteristics of gravels on the Gobi desert surface, which is called the "morphological characteristics gained effectively technique" (McGET). The image of the Gobi desert surface was classified into gravel clusters and background by a machine-learning "classification and regression tree" (CART) algorithm. Then gravel clusters were segmented into individual gravel clasts by separating objects in images using a "watershed segmentation" algorithm. Thirdly, gravel coverage, diameter, aspect ratio and orientation were calculated based on the basic principles of 2D computer graphics. We validated this method with two independent datasets in which the gravel morphological characteristics were obtained from 2728 gravels measured in the field and 7422 gravels measured by manual digitization. Finally, we applied McGET to derive the spatial variation of gravel morphology on the Gobi desert along an alluvial-proluvial fan located in Hami, Xinjiang, China. The validated results show that the mean gravel diameter measured in the field agreed well with that calculated by McGET for large gravels (R2 = 0.89, P < 0.001). Compared to manual digitization, the McGET accuracies for gravel coverage, gravel diameter and aspect ratio were 97%, 83% and 96%, respectively. The orientation distributions calculated were consistent across two different methods. More importantly, McGET significantly shortens the time cost in obtaining gravel morphological characteristics in the field and laboratory. The spatial variation results show that the gravel coverage ranged from 88% to 65%, the gravel diameter was unimodally distributed and ranged from 19 mm to 13 mm. Most gravels were bladed or rod-like, with a mean aspect ratio of 1.57, and had no preferred orientation on the surveyed Gobi desert. From the center to the edge of the fan, gravel coverage decreased 2.2% per 100 m elevation decrease (R2 = 0.69, P < 0.001), mean gravel diameter decreased 0.5 mm per 100 m elevation decrease (R2 = 0.52, P < 0.001), and mean aspect ratio slightly increased 0.004 per 100 m elevation decrease (R2 = 0.26, P < 0.05). These results imply that surface washing was the main process on the investigated Gobi desert. This study demonstrates that the new method can quickly and accurately calculate the gravel coverage, diameter, aspect ratio and orientation from the images of Gobi desert.
An fMRI Study of Grammatical Morpheme Processing Associated with Nouns and Verbs in Chinese
Yu, Xi; Bi, Yanchao; Han, Zaizhu; Law, Sam-Po
2013-01-01
This study examined whether the degree of complexity of a grammatical component in a language would impact on its representation in the brain through identifying the neural correlates of grammatical morpheme processing associated with nouns and verbs in Chinese. In particular, the processing of Chinese nominal classifiers and verbal aspect markers were investigated in a sentence completion task and a grammaticality judgment task to look for converging evidence. The Chinese language constitutes a special case because it has no inflectional morphology per se and a larger classifier than aspect marker inventory, contrary to the pattern of greater verbal than nominal paradigmatic complexity in most European languages. The functional imaging results showed BA47 and left supplementary motor area and superior medial frontal gyrus more strongly activated for classifier processing, and the left posterior middle temporal gyrus more responsive to aspect marker processing. We attributed the activation in the left prefrontal cortex to greater processing complexity during classifier selection, analogous to the accounts put forth for European languages, and the left posterior middle temporal gyrus to more demanding verb semantic processing. The overall findings significantly contribute to cross-linguistic observations of neural substrates underlying processing of grammatical morphemes from an analytic and a classifier language, and thereby deepen our understanding of neurobiology of human language. PMID:24146745
NASA Technical Reports Server (NTRS)
Parada, N. D. J. (Principal Investigator); Paradella, W. R.; Vitorello, I.
1982-01-01
Several aspects of computer-assisted analysis techniques for image enhancement and thematic classification by which LANDSAT MSS imagery may be treated quantitatively are explained. On geological applications, computer processing of digital data allows, possibly, the fullest use of LANDSAT data, by displaying enhanced and corrected data for visual analysis and by evaluating and assigning each spectral pixel information to a given class.
Planetary Data Workshop, Part 2
NASA Technical Reports Server (NTRS)
1984-01-01
Technical aspects of the Planetary Data System (PDS) are addressed. Methods and tools for maintaining and accessing large, complex sets of data are discussed. The specific software and applications needed for processing imaging and non-imaging science data are reviewed. The need for specific software that provides users with information on the location and geometry of scientific observations is discussed. Computer networks and user interface to the PDS are covered along with Computer hardware available to this data system.
Segmentation and automated measurement of chronic wound images: probability map approach
NASA Astrophysics Data System (ADS)
Ahmad Fauzi, Mohammad Faizal; Khansa, Ibrahim; Catignani, Karen; Gordillo, Gayle; Sen, Chandan K.; Gurcan, Metin N.
2014-03-01
estimated 6.5 million patients in the United States are affected by chronic wounds, with more than 25 billion US dollars and countless hours spent annually for all aspects of chronic wound care. There is need to develop software tools to analyze wound images that characterize wound tissue composition, measure their size, and monitor changes over time. This process, when done manually, is time-consuming and subject to intra- and inter-reader variability. In this paper, we propose a method that can characterize chronic wounds containing granulation, slough and eschar tissues. First, we generate a Red-Yellow-Black-White (RYKW) probability map, which then guides the region growing segmentation process. The red, yellow and black probability maps are designed to handle the granulation, slough and eschar tissues, respectively found in wound tissues, while the white probability map is designed to detect the white label card for measurement calibration purpose. The innovative aspects of this work include: 1) Definition of a wound characteristics specific probability map for segmentation, 2) Computationally efficient regions growing on 4D map; 3) Auto-calibration of measurements with the content of the image. The method was applied on 30 wound images provided by the Ohio State University Wexner Medical Center, with the ground truth independently generated by the consensus of two clinicians. While the inter-reader agreement between the readers is 85.5%, the computer achieves an accuracy of 80%.
Mari, João Fernando; Saito, José Hiroki; Neves, Amanda Ferreira; Lotufo, Celina Monteiro da Cruz; Destro-Filho, João-Batista; Nicoletti, Maria do Carmo
2015-12-01
Microelectrode Arrays (MEA) are devices for long term electrophysiological recording of extracellular spontaneous or evocated activities on in vitro neuron culture. This work proposes and develops a framework for quantitative and morphological analysis of neuron cultures on MEAs, by processing their corresponding images, acquired by fluorescence microscopy. The neurons are segmented from the fluorescence channel images using a combination of segmentation by thresholding, watershed transform, and object classification. The positioning of microelectrodes is obtained from the transmitted light channel images using the circular Hough transform. The proposed method was applied to images of dissociated culture of rat dorsal root ganglion (DRG) neuronal cells. The morphological and topological quantitative analysis carried out produced information regarding the state of culture, such as population count, neuron-to-neuron and neuron-to-microelectrode distances, soma morphologies, neuron sizes, neuron and microelectrode spatial distributions. Most of the analysis of microscopy images taken from neuronal cultures on MEA only consider simple qualitative analysis. Also, the proposed framework aims to standardize the image processing and to compute quantitative useful measures for integrated image-signal studies and further computational simulations. As results show, the implemented microelectrode identification method is robust and so are the implemented neuron segmentation and classification one (with a correct segmentation rate up to 84%). The quantitative information retrieved by the method is highly relevant to assist the integrated signal-image study of recorded electrophysiological signals as well as the physical aspects of the neuron culture on MEA. Although the experiments deal with DRG cell images, cortical and hippocampal cell images could also be processed with small adjustments in the image processing parameter estimation.
NASA Astrophysics Data System (ADS)
Utomo, Edy Setiyo; Juniati, Dwi; Siswono, Tatag Yuli Eko
2017-08-01
The aim of this research was to describe the mathematical visualization process of Junior High School students in solving contextual problems based on cognitive style. Mathematical visualization process in this research was seen from aspects of image generation, image inspection, image scanning, and image transformation. The research subject was the students in the eighth grade based on GEFT test (Group Embedded Figures Test) adopted from Within to determining the category of cognitive style owned by the students namely field independent or field dependent and communicative. The data collection was through visualization test in contextual problem and interview. The validity was seen through time triangulation. The data analysis referred to the aspect of mathematical visualization through steps of categorization, reduction, discussion, and conclusion. The results showed that field-independent and field-dependent subjects were difference in responding to contextual problems. The field-independent subject presented in the form of 2D and 3D, while the field-dependent subject presented in the form of 3D. Both of the subjects had different perception to see the swimming pool. The field-independent subject saw from the top, while the field-dependent subject from the side. The field-independent subject chose to use partition-object strategy, while the field-dependent subject chose to use general-object strategy. Both the subjects did transformation in an object rotation to get the solution. This research is reference to mathematical curriculum developers of Junior High School in Indonesia. Besides, teacher could develop the students' mathematical visualization by using technology media or software, such as geogebra, portable cabri in learning.
Caballero Perea, Begoña; Villegas, Antonio Cabrera; Rodríguez, José Miguel Delgado; Velloso, María José García; Vicente, Ana María García; Cabrerizo, Carlos Huerga; López, Rosa Morera; Romasanta, Luis Alberto Pérez; Beltrán, Moisés Sáez
2012-01-01
Positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) is a valuable tool for diagnosing and staging malignant lesions. The fusion of PET and computed tomography (CT) yields images that contain both metabolic and morphological information, which, taken together, have improved the diagnostic precision of PET in oncology. The main imaging modality for planning radiotherapy treatment is CT. However, PET-CT is an emerging modality for use in planning treatments because it allows for more accurate treatment volume definition. The use of PET-CT for treatment planning is highly complex, and protocols and standards for its use are still being developed. It seems probable that PET-CT will eventually replace current CT-based planning methods, but this will require a full understanding of the relevant technical aspects of PET-CT planning. The aim of the present document is to review these technical aspects and to provide recommendations for clinical use of this imaging modality in the radiotherapy planning process.
Caballero Perea, Begoña; Villegas, Antonio Cabrera; Rodríguez, José Miguel Delgado; Velloso, María José García; Vicente, Ana María García; Cabrerizo, Carlos Huerga; López, Rosa Morera; Romasanta, Luis Alberto Pérez; Beltrán, Moisés Sáez
2012-01-01
Positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) is a valuable tool for diagnosing and staging malignant lesions. The fusion of PET and computed tomography (CT) yields images that contain both metabolic and morphological information, which, taken together, have improved the diagnostic precision of PET in oncology. The main imaging modality for planning radiotherapy treatment is CT. However, PET-CT is an emerging modality for use in planning treatments because it allows for more accurate treatment volume definition. The use of PET-CT for treatment planning is highly complex, and protocols and standards for its use are still being developed. It seems probable that PET-CT will eventually replace current CT-based planning methods, but this will require a full understanding of the relevant technical aspects of PET-CT planning. The aim of the present document is to review these technical aspects and to provide recommendations for clinical use of this imaging modality in the radiotherapy planning process. PMID:24377032
Open Technologies at Athabasca University's Geospace Observatories
NASA Astrophysics Data System (ADS)
Connors, M. G.; Schofield, I. S.
2012-12-01
Athabasca University Geophysical Observatories feature two auroral observation sites situated in the subauroral zone of western Canada, separated by approximately 25 km. These sites are both on high-speed internet and ideal for observing phenomena detectable from this latitude, which include noctilucent clouds, meteors, and magnetic and optical aspects of the aurora. General aspects of use of Linux in observatory management are described, with emphasis on recent imaging projects involving control of high resolution digital SLR cameras at low cadence, and inexpensive white light analog video cameras at 30 Hz. Linux shell scripts are extensively used, with image capture controlled by gphoto2, the ivtv-utils package, x264 video coding library, and ffmpeg. Imagemagick allows processing of images in an automated fashion. Image archives and movies are created and can be correlated with magnetic data. Much of the magnetic data stream also uses GMT (Generic Mapping Tools) within shell scripts for display. Additionally, SPASE metadata are generated for most of the magnetic data, thus allowing users of our AUTUMN magnetic data repository to perform SPASE queries on the dataset. Visualization products from our twin observatories will be presented.
NASA Astrophysics Data System (ADS)
Zoratti, Paul K.; Gilbert, R. Kent; Majewski, Ronald; Ference, Jack
1995-12-01
Development of automotive collision warning systems has progressed rapidly over the past several years. A key enabling technology for these systems is millimeter-wave radar. This paper addresses a very critical millimeter-wave radar sensing issue for automotive radar, namely the scattering characteristics of common roadway objects such as vehicles, roadsigns, and bridge overpass structures. The data presented in this paper were collected on ERIM's Fine Resolution Radar Imaging Rotary Platform Facility and processed with ERIM's image processing tools. The value of this approach is that it provides system developers with a 2D radar image from which information about individual point scatterers `within a single target' can be extracted. This information on scattering characteristics will be utilized to refine threat assessment processing algorithms and automotive radar hardware configurations. (1) By evaluating the scattering characteristics identified in the radar image, radar signatures as a function of aspect angle for common roadway objects can be established. These signatures will aid in the refinement of threat assessment processing algorithms. (2) Utilizing ERIM's image manipulation tools, total RCS and RCS as a function of range and azimuth can be extracted from the radar image data. This RCS information will be essential in defining the operational envelope (e.g. dynamic range) within which any radar sensor hardware must be designed.
Forming impressions of facial attractiveness is mandatory.
Ritchie, Kay L; Palermo, Romina; Rhodes, Gillian
2017-03-28
First impressions of social traits, such as attractiveness, from faces are often claimed to be made automatically, given their speed and reliability. However, speed of processing is only one aspect of automaticity. Here we address a further aspect, asking whether impression formation is mandatory. Mandatory formation requires that impressions are formed about social traits even when this is task-irrelevant, and that once formed, these impressions are difficult to inhibit. In two experiments, participants learned what new people looked like for the purpose of future identification, from sets of images high or low in attractiveness. They then rated middle-attractiveness images of each person, for attractiveness. Even though instructed to rate the specific images, not the people, their ratings were biased by the attractiveness of the learned images. A third control experiment, with participants rating names, demonstrated that participants in Experiments 1 and 2 were not simply rating the people, rather than the specific images as instructed. These results show that the formation of attractiveness impressions from faces is mandatory, thus broadening the evidence for automaticity of facial impressions. The mandatory formation of impressions is likely to have an important impact in real-world situations such as online dating sites.
Optimized Laplacian image sharpening algorithm based on graphic processing unit
NASA Astrophysics Data System (ADS)
Ma, Tinghuai; Li, Lu; Ji, Sai; Wang, Xin; Tian, Yuan; Al-Dhelaan, Abdullah; Al-Rodhaan, Mznah
2014-12-01
In classical Laplacian image sharpening, all pixels are processed one by one, which leads to large amount of computation. Traditional Laplacian sharpening processed on CPU is considerably time-consuming especially for those large pictures. In this paper, we propose a parallel implementation of Laplacian sharpening based on Compute Unified Device Architecture (CUDA), which is a computing platform of Graphic Processing Units (GPU), and analyze the impact of picture size on performance and the relationship between the processing time of between data transfer time and parallel computing time. Further, according to different features of different memory, an improved scheme of our method is developed, which exploits shared memory in GPU instead of global memory and further increases the efficiency. Experimental results prove that two novel algorithms outperform traditional consequentially method based on OpenCV in the aspect of computing speed.
Computational aspects of geometric correction data generation in the LANDSAT-D imagery processing
NASA Technical Reports Server (NTRS)
Levine, I.
1981-01-01
A method is presented for systematic and geodetic correction data calculation. It is based on presentation of image distortions as a sum of nominal distortions and linear effects caused by variation of the spacecraft position and attitude variables from their nominals. The method may be used for both MSS and TM image data and it is incorporated into the processing by means of mostly offline calculations. Modeling shows that the maximal of the method are of the order of 5m at the worst point in a frame; the standard deviations of the average errors less than .8m.
Embedded mobile farm robot for identification of diseased plants
NASA Astrophysics Data System (ADS)
Sadistap, S. S.; Botre, B. A.; Pandit, Harshavardhan; Chandrasekhar; Rao, Adesh
2013-07-01
This paper presents the development of a mobile robot used in farms for identification of diseased plants. It puts forth two of the major aspects of robotics namely automated navigation and image processing. The robot navigates on the basis of the GPS (Global Positioning System) location and data obtained from IR (Infrared) sensors to avoid any obstacles in its path. It uses an image processing algorithm to differentiate between diseased and non-diseased plants. A robotic platform consisting of an ARM9 processor, motor drivers, robot mechanical assembly, camera and infrared sensors has been used. Mini2440 microcontroller has been used wherein Embedded linux OS (Operating System) is implemented.
Notes to Parents - When Your Child Has Undergone Amputation.
ERIC Educational Resources Information Center
Pierson, Margaret Hauser
Designed to provide parents with basic information about the physical and emotional aspects of amputation, the booklet gives information about the grief response, body image, phantom limb sensation, stump care, and the prosthesis. The section on the grief process describes normal reactions to loss: denial, anger, bargaining, depression, and…
Neuronal Effects of Auditory Distraction on Visual Attention
ERIC Educational Resources Information Center
Smucny, Jason; Rojas, Donald C.; Eichman, Lindsay C.; Tregellas, Jason R.
2013-01-01
Selective attention in the presence of distraction is a key aspect of healthy cognition. The underlying neurobiological processes, have not, however, been functionally well characterized. In the present study, we used functional magnetic resonance imaging to determine how ecologically relevant distracting noise affects cortical activity in 27…
Requirements for a documentation of the image manipulation processes within PACS
NASA Astrophysics Data System (ADS)
Retter, Klaus; Rienhoff, Otto; Karsten, Ch.; Prince, Hazel E.
1990-08-01
This paper discusses to which extent manipulation functions which have been applied to images handled in PACS should be documented. After postulating an increasing amount of postprocessing features on PACS-consoles, legal, educational and medical reasons for a documentation of image manipulation processes are presented. Besides legal necessities, aspects of storage capacity, response time, and potential uses determine the extent of this documentation. Is there a specific kind of manipulation functions which has to be documented generally? Should the physician decide which parts of the various pathways he tries are recorded by the system? To distinguish, for example, between reversible and irreversible functions or between interactive and non-interactive functions is one step towards a solution. Another step is to establish definitions for terms like "raw" and "final" image. The paper systematizes these questions and offers strategic help. The answers will have an important impact on PACS design and functionality.
Karnowski, Karol; Ajduk, Anna; Wieloch, Bartosz; Tamborski, Szymon; Krawiec, Krzysztof; Wojtkowski, Maciej; Szkulmowski, Maciej
2017-06-23
Imaging of living cells based on traditional fluorescence and confocal laser scanning microscopy has delivered an enormous amount of information critical for understanding biological processes in single cells. However, the requirement for a high numerical aperture and fluorescent markers still limits researchers' ability to visualize the cellular architecture without causing short- and long-term photodamage. Optical coherence microscopy (OCM) is a promising alternative that circumvents the technical limitations of fluorescence imaging techniques and provides unique access to fundamental aspects of early embryonic development, without the requirement for sample pre-processing or labeling. In the present paper, we utilized the internal motion of cytoplasm, as well as custom scanning and signal processing protocols, to effectively reduce the speckle noise typical for standard OCM and enable high-resolution intracellular time-lapse imaging. To test our imaging system we used mouse and pig oocytes and embryos and visualized them through fertilization and the first embryonic division, as well as at selected stages of oogenesis and preimplantation development. Because all morphological and morphokinetic properties recorded by OCM are believed to be biomarkers of oocyte/embryo quality, OCM may represent a new chapter in imaging-based preimplantation embryo diagnostics.
Applying high resolution remote sensing image and DEM to falling boulder hazard assessment
NASA Astrophysics Data System (ADS)
Huang, Changqing; Shi, Wenzhong; Ng, K. C.
2005-10-01
Boulder fall hazard assessing generally requires gaining the boulder information. The extensive mapping and surveying fieldwork is a time-consuming, laborious and dangerous conventional method. So this paper proposes an applying image processing technology to extract boulder and assess boulder fall hazard from high resolution remote sensing image. The method can replace the conventional method and extract the boulder information in high accuracy, include boulder size, shape, height and the slope and aspect of its position. With above boulder information, it can be satisfied for assessing, prevention and cure boulder fall hazard.
1981-01-01
Video cameras with contrast and black level controls can yield polarized light and differential interference contrast microscope images with unprecedented image quality, resolution, and recording speed. The theoretical basis and practical aspects of video polarization and differential interference contrast microscopy are discussed and several applications in cell biology are illustrated. These include: birefringence of cortical structures and beating cilia in Stentor, birefringence of rotating flagella on a single bacterium, growth and morphogenesis of echinoderm skeletal spicules in culture, ciliary and electrical activity in a balancing organ of a nudibranch snail, and acrosomal reaction in activated sperm. PMID:6788777
Implementation Analysis of Cutting Tool Carbide with Cast Iron Material S45 C on Universal Lathe
NASA Astrophysics Data System (ADS)
Junaidi; hestukoro, Soni; yanie, Ahmad; Jumadi; Eddy
2017-12-01
Cutting tool is the tools lathe. Cutting process tool CARBIDE with Cast Iron Material Universal Lathe which is commonly found at Analysiscutting Process by some aspects numely Cutting force, Cutting Speed, Cutting Power, Cutting Indication Power, Temperature Zone 1 and Temperatur Zone 2. Purpose of this Study was to determine how big the cutting Speed, Cutting Power, electromotor Power,Temperatur Zone 1 and Temperatur Zone 2 that drives the chisel cutting CARBIDE in the Process of tur ning Cast Iron Material. Cutting force obtained from image analysis relationship between the recommended Component Cuting Force with plane of the cut and Cutting Speed obtained from image analysis of relationships between the recommended Cutting Speed Feed rate.
Imaging cell competition in Drosophila imaginal discs.
Ohsawa, Shizue; Sugimura, Kaoru; Takino, Kyoko; Igaki, Tatsushi
2012-01-01
Cell competition is a process in which cells with higher fitness ("winners") survive and proliferate at the expense of less fit neighbors ("losers"). It has been suggested that cell competition is involved in a variety of biological processes such as organ size control, tissue homeostasis, cancer progression, and the maintenance of stem cell population. By advent of a genetic mosaic technique, which enables to generate fluorescently marked somatic clones in Drosophila imaginal discs, recent studies have presented some aspects of molecular mechanisms underlying cell competition. Now, with a live-imaging technique using ex vivo-cultured imaginal discs, we can dissect the spatiotemporal nature of competitive cell behaviors within multicellular communities. Here, we describe procedures and tips for live imaging of cell competition in Drosophila imaginal discs. Copyright © 2012 Elsevier Inc. All rights reserved.
WE-E-BRD-01: HDR Brachytherapy I: Overview of Clinical Application and QA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Libby, B; Showalter, T
2014-06-15
With the increased usage of high dose rate (HDR) brachytherapy and the introduction of dedicated image guided brachytherapy suites, it is necessary to review the processes and procedures associated with safely delivering these treatments in the expedited time scales that dedicated treatment suites afford. The speakers will present the clinical aspects of switching from LDR to HDR treatments, including guidelines for patient selection, and the clinical outcomes comparing LDR to HDR. The speakers will also discuss the HDR treatment process itself, because the shortened clinical timeline involved with a streamlined scan/plan/treat workflow can introduce other issues. Safety and QA aspectsmore » involved with the streamlined process, including increased personnel required for parallel tasks, and possible interfering tasks causing delays in patient treatments will also be discussed. Learning Objectives: To understand the clinical aspects of HDR Brachytherapy, including common clinical indications, patient selection, and the evolving evidence in support of this therapeutic modality To review the current prominent clinical trials for HDR brachytherapy To interpret the established guidelines for HDR brachytherapy quality assurance for implementation into practical clinical settings. To introduce the basic requirements for image guided brachytherapy.« less
ERIC Educational Resources Information Center
Tallman, Oliver H.
A digital simulation of a model for the processing of visual images is derived from known aspects of the human visual system. The fundamental principle of computation suggested by a biological model is a transformation that distributes information contained in an input stimulus everywhere in a transform domain. Each sensory input contributes under…
Endoscopic fluorescence imaging for early assessment of anastomotic recurrence of Crohn's disease
NASA Astrophysics Data System (ADS)
Mordon, Serge R.; Maunoury, Vincent; Geboes, K.; Klein, Olivier; Desreumaux, P.; Debaert, A.; Colombel, Jean-Frederic
1999-02-01
Crohn's disease is an inflammatory bowel disease of unknown etiology. The mechanism of the initial mucosal alterations is still unclear: ulcerations overlying lymphoid follicles and/or vasculitis have been proposed as the early lesions. We have developed a new and original method combining endoscopy of fluorescence angiography for identifying the early pathological lesions, occurring in the neo-terminal ileum after right ileocolonic resection. The patient population consisted of 10 subjects enrolled in a prospective protocol of endoscopic follow-up at 3 and 12 months after surgery. Fluorescence imaging showed small spots giving a bright fluorescence distributed singly in mucosa which appeared normal in routine endoscopy. Histopathological examination demonstrated that the fluorescence of small spots originated from small, usually superficial, erosive lesions. In several cases, these erosive lesions occurred over lymphoid follicles. Endoscopic fluorescence imaging provides a suitable means of investigating the initial aspect of the Crohn's disease process in displaying some correlative findings between fluorescent aspects and early pathological mucosal alterations.
Physically-based in silico light sheet microscopy for visualizing fluorescent brain models
2015-01-01
Background We present a physically-based computational model of the light sheet fluorescence microscope (LSFM). Based on Monte Carlo ray tracing and geometric optics, our method simulates the operational aspects and image formation process of the LSFM. This simulated, in silico LSFM creates synthetic images of digital fluorescent specimens that can resemble those generated by a real LSFM, as opposed to established visualization methods producing visually-plausible images. We also propose an accurate fluorescence rendering model which takes into account the intrinsic characteristics of fluorescent dyes to simulate the light interaction with fluorescent biological specimen. Results We demonstrate first results of our visualization pipeline to a simplified brain tissue model reconstructed from the somatosensory cortex of a young rat. The modeling aspects of the LSFM units are qualitatively analysed, and the results of the fluorescence model were quantitatively validated against the fluorescence brightness equation and characteristic emission spectra of different fluorescent dyes. AMS subject classification Modelling and simulation PMID:26329404
Towards diverse visual suggestions on Flickr
NASA Astrophysics Data System (ADS)
Feki, Ghada; Ben Ammar, Anis; Ben Amar, Chokri
2017-03-01
With the great popularity of the photo sharing site Flickr, the research community is involved to produce innovative applications in order to enhance different Flickr services. In this paper, we present a new process for diverse visual suggestions generation on Flickr. We unify the social aspect of Flickr and the richness of Wikipedia to produce an important number of meanings illustrated by the diverse visual suggestions which can integrate the diversity aspect into the Flickr search. We conduct an experimental study to illustrate the effect of the fusion of the Wikipedia and Flickr knowledge on the diversity rate among the Flickr search and reveal the evolution of the diversity aspect through the returned images among the different results of search engines.
Object-related activity revealed by functional magnetic resonance imaging in human occipital cortex.
Malach, R; Reppas, J B; Benson, R R; Kwong, K K; Jiang, H; Kennedy, W A; Ledden, P J; Brady, T J; Rosen, B R; Tootell, R B
1995-01-01
The stages of integration leading from local feature analysis to object recognition were explored in human visual cortex by using the technique of functional magnetic resonance imaging. Here we report evidence for object-related activation. Such activation was located at the lateral-posterior aspect of the occipital lobe, just abutting the posterior aspect of the motion-sensitive area MT/V5, in a region termed the lateral occipital complex (LO). LO showed preferential activation to images of objects, compared to a wide range of texture patterns. This activation was not caused by a global difference in the Fourier spatial frequency content of objects versus texture images, since object images produced enhanced LO activation compared to textures matched in power spectra but randomized in phase. The preferential activation to objects also could not be explained by different patterns of eye movements: similar levels of activation were observed when subjects fixated on the objects and when they scanned the objects with their eyes. Additional manipulations such as spatial frequency filtering and a 4-fold change in visual size did not affect LO activation. These results suggest that the enhanced responses to objects were not a manifestation of low-level visual processing. A striking demonstration that activity in LO is uniquely correlated to object detectability was produced by the "Lincoln" illusion, in which blurring of objects digitized into large blocks paradoxically increases their recognizability. Such blurring led to significant enhancement of LO activation. Despite the preferential activation to objects, LO did not seem to be involved in the final, "semantic," stages of the recognition process. Thus, objects varying widely in their recognizability (e.g., famous faces, common objects, and unfamiliar three-dimensional abstract sculptures) activated it to a similar degree. These results are thus evidence for an intermediate link in the chain of processing stages leading to object recognition in human visual cortex. Images Fig. 1 Fig. 2 Fig. 3 PMID:7667258
Advances in diffusion MRI acquisition and processing in the Human Connectome Project
Sotiropoulos, Stamatios N; Jbabdi, Saad; Xu, Junqian; Andersson, Jesper L; Moeller, Steen; Auerbach, Edward J; Glasser, Matthew F; Hernandez, Moises; Sapiro, Guillermo; Jenkinson, Mark; Feinberg, David A; Yacoub, Essa; Lenglet, Christophe; Ven Essen, David C; Ugurbil, Kamil; Behrens, Timothy EJ
2013-01-01
The Human Connectome Project (HCP) is a collaborative 5-year effort to map human brain connections and their variability in healthy adults. A consortium of HCP investigators will study a population of 1200 healthy adults using multiple imaging modalities, along with extensive behavioral and genetic data. In this overview, we focus on diffusion MRI (dMRI) and the structural connectivity aspect of the project. We present recent advances in acquisition and processing that allow us to obtain very high-quality in-vivo MRI data, while enabling scanning of a very large number of subjects. These advances result from 2 years of intensive efforts in optimising many aspects of data acquisition and processing during the piloting phase of the project. The data quality and methods described here are representative of the datasets and processing pipelines that will be made freely available to the community at quarterly intervals, beginning in 2013. PMID:23702418
GPU-Based High-performance Imaging for Mingantu Spectral RadioHeliograph
NASA Astrophysics Data System (ADS)
Mei, Ying; Wang, Feng; Wang, Wei; Chen, Linjie; Liu, Yingbo; Deng, Hui; Dai, Wei; Liu, Cuiyin; Yan, Yihua
2018-01-01
As a dedicated solar radio interferometer, the MingantU SpEctral RadioHeliograph (MUSER) generates massive observational data in the frequency range of 400 MHz-15 GHz. High-performance imaging forms a significantly important aspect of MUSER’s massive data processing requirements. In this study, we implement a practical high-performance imaging pipeline for MUSER data processing. At first, the specifications of the MUSER are introduced and its imaging requirements are analyzed. Referring to the most commonly used radio astronomy software such as CASA and MIRIAD, we then implement a high-performance imaging pipeline based on the Graphics Processing Unit technology with respect to the current operational status of the MUSER. A series of critical algorithms and their pseudo codes, i.e., detection of the solar disk and sky brightness, automatic centering of the solar disk and estimation of the number of iterations for clean algorithms, are proposed in detail. The preliminary experimental results indicate that the proposed imaging approach significantly increases the processing performance of MUSER and generates images with high-quality, which can meet the requirements of the MUSER data processing. Supported by the National Key Research and Development Program of China (2016YFE0100300), the Joint Research Fund in Astronomy (No. U1531132, U1631129, U1231205) under cooperative agreement between the National Natural Science Foundation of China (NSFC) and the Chinese Academy of Sciences (CAS), the National Natural Science Foundation of China (Nos. 11403009 and 11463003).
Wang, Juan; Nishikawa, Robert M; Yang, Yongyi
2017-07-01
Mammograms acquired with full-field digital mammography (FFDM) systems are provided in both "for-processing'' and "for-presentation'' image formats. For-presentation images are traditionally intended for visual assessment by the radiologists. In this study, we investigate the feasibility of using for-presentation images in computerized analysis and diagnosis of microcalcification (MC) lesions. We make use of a set of 188 matched mammogram image pairs of MC lesions from 95 cases (biopsy proven), in which both for-presentation and for-processing images are provided for each lesion. We then analyze and characterize the MC lesions from for-presentation images and compare them with their counterparts in for-processing images. Specifically, we consider three important aspects in computer-aided diagnosis (CAD) of MC lesions. First, we quantify each MC lesion with a set of 10 image features of clustered MCs and 12 textural features of the lesion area. Second, we assess the detectability of individual MCs in each lesion from the for-presentation images by a commonly used difference-of-Gaussians (DoG) detector. Finally, we study the diagnostic accuracy in discriminating between benign and malignant MC lesions from the for-presentation images by a pretrained support vector machine (SVM) classifier. To accommodate the underlying background suppression and image enhancement in for-presentation images, a normalization procedure is applied. The quantitative image features of MC lesions from for-presentation images are highly consistent with that from for-processing images. The values of Pearson's correlation coefficient between features from the two formats range from 0.824 to 0.961 for the 10 MC image features, and from 0.871 to 0.963 for the 12 textural features. In detection of individual MCs, the FROC curve from for-presentation is similar to that from for-processing. In particular, at sensitivity level of 80%, the average number of false-positives (FPs) per image region is 9.55 for both for-presentation and for-processing images. Finally, for classifying MC lesions as malignant or benign, the area under the ROC curve is 0.769 in for-presentation, compared to 0.761 in for-processing (P = 0.436). The quantitative results demonstrate that MC lesions in for-presentation images are highly consistent with that in for-processing images in terms of image features, detectability of individual MCs, and classification accuracy between malignant and benign lesions. These results indicate that for-presentation images can be compatible with for-processing images for use in CAD algorithms for MC lesions. © 2017 American Association of Physicists in Medicine.
X-ray mask and method for providing same
Morales, Alfredo M [Pleasanton, CA; Skala, Dawn M [Fremont, CA
2004-09-28
The present invention describes a method for fabricating an x-ray mask tool which can achieve pattern features having lateral dimension of less than 1 micron. The process uses a thin photoresist and a standard lithographic mask to transfer an trace image pattern in the surface of a silicon wafer by exposing and developing the resist. The exposed portion of the silicon substrate is then anisotropically etched to provide an etched image of the trace image pattern consisting of a series of channels in the silicon having a high depth-to-width aspect ratio. These channels are then filled by depositing a metal such as gold to provide an inverse image of the trace image and thereby providing a robust x-ray mask tool.
X-ray mask and method for providing same
Morales, Alfredo M.; Skala, Dawn M.
2002-01-01
The present invention describes a method for fabricating an x-ray mask tool which can achieve pattern features having lateral dimension of less than 1 micron. The process uses a thin photoresist and a standard lithographic mask to transfer an trace image pattern in the surface of a silicon wafer by exposing and developing the resist. The exposed portion of the silicon substrate is then anisotropically etched to provide an etched image of the trace image pattern consisting of a series of channels in the silicon having a high depth-to-width aspect ratio. These channels are then filled by depositing a metal such as gold to provide an inverse image of the trace image and thereby providing a robust x-ray mask tool.
Analysis and characterization of high-resolution and high-aspect-ratio imaging fiber bundles.
Motamedi, Nojan; Karbasi, Salman; Ford, Joseph E; Lomakin, Vitaliy
2015-11-10
High-contrast imaging fiber bundles (FBs) are characterized and modeled for wide-angle and high-resolution imaging applications. Scanning electron microscope images of FB cross sections are taken to measure physical parameters and verify the variations of irregular fibers due to the fabrication process. Modal analysis tools are developed that include irregularities in the fiber core shapes and provide results in agreement with experimental measurements. The modeling demonstrates that the irregular fibers significantly outperform a perfectly regular "ideal" array. Using this method, FBs are designed that can provide high contrast with core pitches of only a few wavelengths of the guided light. Structural modifications of the commercially available FB can reduce the core pitch by 60% for higher resolution image relay.
Image acquisition in the Pi-of-the-Sky project
NASA Astrophysics Data System (ADS)
Jegier, M.; Nawrocki, K.; Poźniak, K.; Sokołowski, M.
2006-10-01
Modern astronomical image acquisition systems dedicated for sky surveys provide large amount of data in a single measurement session. During one session that lasts a few hours it is possible to get as much as 100 GB of data. This large amount of data needs to be transferred from camera and processed. This paper presents some aspects of image acquisition in a sky survey image acquisition system. It describes a dedicated USB linux driver for the first version of the "Pi of The Sky" CCD camera (later versions have also Ethernet interface) and the test program for the camera together with a driver-wrapper providing core device functionality. Finally, the paper contains description of an algorithm for matching several images based on image features, i.e. star positions and their brightness.
Colour image segmentation using unsupervised clustering technique for acute leukemia images
NASA Astrophysics Data System (ADS)
Halim, N. H. Abd; Mashor, M. Y.; Nasir, A. S. Abdul; Mustafa, N.; Hassan, R.
2015-05-01
Colour image segmentation has becoming more popular for computer vision due to its important process in most medical analysis tasks. This paper proposes comparison between different colour components of RGB(red, green, blue) and HSI (hue, saturation, intensity) colour models that will be used in order to segment the acute leukemia images. First, partial contrast stretching is applied on leukemia images to increase the visual aspect of the blast cells. Then, an unsupervised moving k-means clustering algorithm is applied on the various colour components of RGB and HSI colour models for the purpose of segmentation of blast cells from the red blood cells and background regions in leukemia image. Different colour components of RGB and HSI colour models have been analyzed in order to identify the colour component that can give the good segmentation performance. The segmented images are then processed using median filter and region growing technique to reduce noise and smooth the images. The results show that segmentation using saturation component of HSI colour model has proven to be the best in segmenting nucleus of the blast cells in acute leukemia image as compared to the other colour components of RGB and HSI colour models.
Image counter-forensics based on feature injection
NASA Astrophysics Data System (ADS)
Iuliani, M.; Rossetto, S.; Bianchi, T.; De Rosa, Alessia; Piva, A.; Barni, M.
2014-02-01
Starting from the concept that many image forensic tools are based on the detection of some features revealing a particular aspect of the history of an image, in this work we model the counter-forensic attack as the injection of a specific fake feature pointing to the same history of an authentic reference image. We propose a general attack strategy that does not rely on a specific detector structure. Given a source image x and a target image y, the adversary processes x in the pixel domain producing an attacked image ~x, perceptually similar to x, whose feature f(~x) is as close as possible to f(y) computed on y. Our proposed counter-forensic attack consists in the constrained minimization of the feature distance Φ(z) =│ f(z) - f(y)│ through iterative methods based on gradient descent. To solve the intrinsic limit due to the numerical estimation of the gradient on large images, we propose the application of a feature decomposition process, that allows the problem to be reduced into many subproblems on the blocks the image is partitioned into. The proposed strategy has been tested by attacking three different features and its performance has been compared to state-of-the-art counter-forensic methods.
Iyappan, Anandhi; Younesi, Erfan; Redolfi, Alberto; Vrooman, Henri; Khanna, Shashank; Frisoni, Giovanni B; Hofmann-Apitius, Martin
2017-01-01
Ontologies and terminologies are used for interoperability of knowledge and data in a standard manner among interdisciplinary research groups. Existing imaging ontologies capture general aspects of the imaging domain as a whole such as methodological concepts or calibrations of imaging instruments. However, none of the existing ontologies covers the diagnostic features measured by imaging technologies in the context of neurodegenerative diseases. Therefore, the Neuro-Imaging Feature Terminology (NIFT) was developed to organize the knowledge domain of measured brain features in association with neurodegenerative diseases by imaging technologies. The purpose is to identify quantitative imaging biomarkers that can be extracted from multi-modal brain imaging data. This terminology attempts to cover measured features and parameters in brain scans relevant to disease progression. In this paper, we demonstrate the systematic retrieval of measured indices from literature and how the extracted knowledge can be further used for disease modeling that integrates neuroimaging features with molecular processes.
Chen, Chieh-Li; Ishikawa, Hiroshi; Wollstein, Gadi; Bilonick, Richard A; Kagemann, Larry; Schuman, Joel S
2016-01-01
Developing a novel image enhancement method so that nonframe-averaged optical coherence tomography (OCT) images become comparable to active eye-tracking frame-averaged OCT images. Twenty-one eyes of 21 healthy volunteers were scanned with noneye-tracking nonframe-averaged OCT device and active eye-tracking frame-averaged OCT device. Virtual averaging was applied to nonframe-averaged images with voxel resampling and adding amplitude deviation with 15-time repetitions. Signal-to-noise (SNR), contrast-to-noise ratios (CNR), and the distance between the end of visible nasal retinal nerve fiber layer (RNFL) and the foveola were assessed to evaluate the image enhancement effect and retinal layer visibility. Retinal thicknesses before and after processing were also measured. All virtual-averaged nonframe-averaged images showed notable improvement and clear resemblance to active eye-tracking frame-averaged images. Signal-to-noise and CNR were significantly improved (SNR: 30.5 vs. 47.6 dB, CNR: 4.4 vs. 6.4 dB, original versus processed, P < 0.0001, paired t -test). The distance between the end of visible nasal RNFL and the foveola was significantly different before (681.4 vs. 446.5 μm, Cirrus versus Spectralis, P < 0.0001) but not after processing (442.9 vs. 446.5 μm, P = 0.76). Sectoral macular total retinal and circumpapillary RNFL thicknesses showed systematic differences between Cirrus and Spectralis that became not significant after processing. The virtual averaging method successfully improved nontracking nonframe-averaged OCT image quality and made the images comparable to active eye-tracking frame-averaged OCT images. Virtual averaging may enable detailed retinal structure studies on images acquired using a mixture of nonframe-averaged and frame-averaged OCT devices without concerning about systematic differences in both qualitative and quantitative aspects.
Chen, Chieh-Li; Ishikawa, Hiroshi; Wollstein, Gadi; Bilonick, Richard A.; Kagemann, Larry; Schuman, Joel S.
2016-01-01
Purpose Developing a novel image enhancement method so that nonframe-averaged optical coherence tomography (OCT) images become comparable to active eye-tracking frame-averaged OCT images. Methods Twenty-one eyes of 21 healthy volunteers were scanned with noneye-tracking nonframe-averaged OCT device and active eye-tracking frame-averaged OCT device. Virtual averaging was applied to nonframe-averaged images with voxel resampling and adding amplitude deviation with 15-time repetitions. Signal-to-noise (SNR), contrast-to-noise ratios (CNR), and the distance between the end of visible nasal retinal nerve fiber layer (RNFL) and the foveola were assessed to evaluate the image enhancement effect and retinal layer visibility. Retinal thicknesses before and after processing were also measured. Results All virtual-averaged nonframe-averaged images showed notable improvement and clear resemblance to active eye-tracking frame-averaged images. Signal-to-noise and CNR were significantly improved (SNR: 30.5 vs. 47.6 dB, CNR: 4.4 vs. 6.4 dB, original versus processed, P < 0.0001, paired t-test). The distance between the end of visible nasal RNFL and the foveola was significantly different before (681.4 vs. 446.5 μm, Cirrus versus Spectralis, P < 0.0001) but not after processing (442.9 vs. 446.5 μm, P = 0.76). Sectoral macular total retinal and circumpapillary RNFL thicknesses showed systematic differences between Cirrus and Spectralis that became not significant after processing. Conclusion The virtual averaging method successfully improved nontracking nonframe-averaged OCT image quality and made the images comparable to active eye-tracking frame-averaged OCT images. Translational Relevance Virtual averaging may enable detailed retinal structure studies on images acquired using a mixture of nonframe-averaged and frame-averaged OCT devices without concerning about systematic differences in both qualitative and quantitative aspects. PMID:26835180
Image quality prediction - An aid to the Viking lander imaging investigation on Mars
NASA Technical Reports Server (NTRS)
Huck, F. O.; Wall, S. D.
1976-01-01
Image quality criteria and image quality predictions are formulated for the multispectral panoramic cameras carried by the Viking Mars landers. Image quality predictions are based on expected camera performance, Mars surface radiance, and lighting and viewing geometry (fields of view, Mars lander shadows, solar day-night alternation), and are needed in diagnosis of camera performance, in arriving at a preflight imaging strategy, and revision of that strategy should the need arise. Landing considerations, camera control instructions, camera control logic, aspects of the imaging process (spectral response, spatial response, sensitivity), and likely problems are discussed. Major concerns include: degradation of camera response by isotope radiation, uncertainties in lighting and viewing geometry and in landing site local topography, contamination of camera window by dust abrasion, and initial errors in assigning camera dynamic ranges (gains and offsets).
Gintautas, Vadas; Ham, Michael I.; Kunsberg, Benjamin; Barr, Shawn; Brumby, Steven P.; Rasmussen, Craig; George, John S.; Nemenman, Ilya; Bettencourt, Luís M. A.; Kenyon, Garret T.
2011-01-01
Can lateral connectivity in the primary visual cortex account for the time dependence and intrinsic task difficulty of human contour detection? To answer this question, we created a synthetic image set that prevents sole reliance on either low-level visual features or high-level context for the detection of target objects. Rendered images consist of smoothly varying, globally aligned contour fragments (amoebas) distributed among groups of randomly rotated fragments (clutter). The time course and accuracy of amoeba detection by humans was measured using a two-alternative forced choice protocol with self-reported confidence and variable image presentation time (20-200 ms), followed by an image mask optimized so as to interrupt visual processing. Measured psychometric functions were well fit by sigmoidal functions with exponential time constants of 30-91 ms, depending on amoeba complexity. Key aspects of the psychophysical experiments were accounted for by a computational network model, in which simulated responses across retinotopic arrays of orientation-selective elements were modulated by cortical association fields, represented as multiplicative kernels computed from the differences in pairwise edge statistics between target and distractor images. Comparing the experimental and the computational results suggests that each iteration of the lateral interactions takes at least ms of cortical processing time. Our results provide evidence that cortical association fields between orientation selective elements in early visual areas can account for important temporal and task-dependent aspects of the psychometric curves characterizing human contour perception, with the remaining discrepancies postulated to arise from the influence of higher cortical areas. PMID:21998562
Semi-Global Matching with Self-Adjusting Penalties
NASA Astrophysics Data System (ADS)
Karkalou, E.; Stentoumis, C.; Karras, G.
2017-02-01
The demand for 3D models of various scales and precisions is strong for a wide range of applications, among which cultural heritage recording is particularly important and challenging. In this context, dense image matching is a fundamental task for processes which involve image-based reconstruction of 3D models. Despite the existence of commercial software, the need for complete and accurate results under different conditions, as well as for computational efficiency under a variety of hardware, has kept image-matching algorithms as one of the most active research topics. Semi-global matching (SGM) is among the most popular optimization algorithms due to its accuracy, computational efficiency, and simplicity. A challenging aspect in SGM implementation is the determination of smoothness constraints, i.e. penalties P1, P2 for disparity changes and discontinuities. In fact, penalty adjustment is needed for every particular stereo-pair and cost computation. In this work, a novel formulation of self-adjusting penalties is proposed: SGM penalties can be estimated solely from the statistical properties of the initial disparity space image. The proposed method of self-adjusting penalties (SGM-SAP) is evaluated using typical cost functions on stereo-pairs from the recent Middlebury dataset of interior scenes, as well as from the EPFL Herz-Jesu architectural scenes. Results are competitive against the original SGM estimates. The significant aspects of self-adjusting penalties are: (i) the time-consuming tuning process is avoided; (ii) SGM can be used in image collections with limited number of stereo-pairs; and (iii) no heuristic user intervention is needed.
fMRI paradigm designing and post-processing tools
James, Jija S; Rajesh, PG; Chandran, Anuvitha VS; Kesavadas, Chandrasekharan
2014-01-01
In this article, we first review some aspects of functional magnetic resonance imaging (fMRI) paradigm designing for major cognitive functions by using stimulus delivery systems like Cogent, E-Prime, Presentation, etc., along with their technical aspects. We also review the stimulus presentation possibilities (block, event-related) for visual or auditory paradigms and their advantage in both clinical and research setting. The second part mainly focus on various fMRI data post-processing tools such as Statistical Parametric Mapping (SPM) and Brain Voyager, and discuss the particulars of various preprocessing steps involved (realignment, co-registration, normalization, smoothing) in these software and also the statistical analysis principles of General Linear Modeling for final interpretation of a functional activation result. PMID:24851001
Developing Creativity and Abstraction in Representing Data
ERIC Educational Resources Information Center
South, Andy
2012-01-01
Creating charts and graphs is all about visual abstraction: the process of representing aspects of data with imagery that can be interpreted by the reader. Children may need help making the link between the "real" and the image. This abstraction can be achieved using symbols, size, colour and position. Where the representation is close to what…
Image reconstruction for PET/CT scanners: past achievements and future challenges
Tong, Shan; Alessio, Adam M; Kinahan, Paul E
2011-01-01
PET is a medical imaging modality with proven clinical value for disease diagnosis and treatment monitoring. The integration of PET and CT on modern scanners provides a synergy of the two imaging modalities. Through different mathematical algorithms, PET data can be reconstructed into the spatial distribution of the injected radiotracer. With dynamic imaging, kinetic parameters of specific biological processes can also be determined. Numerous efforts have been devoted to the development of PET image reconstruction methods over the last four decades, encompassing analytic and iterative reconstruction methods. This article provides an overview of the commonly used methods. Current challenges in PET image reconstruction include more accurate quantitation, TOF imaging, system modeling, motion correction and dynamic reconstruction. Advances in these aspects could enhance the use of PET/CT imaging in patient care and in clinical research studies of pathophysiology and therapeutic interventions. PMID:21339831
Hangiandreou, Nicholas J
2003-01-01
Ultrasonography (US) has been used in medical imaging for over half a century. Current US scanners are based largely on the same basic principles used in the initial devices for human imaging. Modern equipment uses a pulse-echo approach with a brightness-mode (B-mode) display. Fundamental aspects of the B-mode imaging process include basic ultrasound physics, interactions of ultrasound with tissue, ultrasound pulse formation, scanning the ultrasound beam, and echo detection and signal processing. Recent technical innovations that have been developed to improve the performance of modern US equipment include the following: tissue harmonic imaging, spatial compound imaging, extended field of view imaging, coded pulse excitation, electronic section focusing, three-dimensional and four-dimensional imaging, and the general trend toward equipment miniaturization. US is a relatively inexpensive, portable, safe, and real-time modality, all of which make it one of the most widely used imaging modalities in medicine. Although B-mode US is sometimes referred to as a mature technology, this modality continues to experience a significant evolution in capability with even more exciting developments on the horizon. Copyright RSNA, 2003
An analysis of logical thinking using mind mapping
NASA Astrophysics Data System (ADS)
Swestyani, S.; Masykuri, M.; Prayitno, B. A.; Rinanto, Y.; Widoretno, S.
2018-05-01
Brains can remember information in different forms, i.e images, symbols, sounds, and senses, and the information is connected by logical gate. This information needs imagination and association to construct new meaningful images. The purpose of this research was to describe a method of teaching which based on Tony Buzan’s mind mapping technique. This research showed how mind mapping could be used to measure students’ logical thinking and how mind mapping could promote students’ understanding in meaningful way. The test of mind mapping that involved 31 students of XI grade in SMA Batik 2 Surakarta was used as the data collecting method in this research. Then, the Ohassta’s mind mapping rubric was used to analyze the structure and content of mind mapping. The rubric includes four aspects, i.e knowledge, communication, thinking, and application. A qualitative analysis Miles and Hubberman’s was used to assess the obtained data. The result showed that the percentage of knowledge aspect was 53,23 %, communication aspect was 28,33 %, thinking aspect was 28,33 %, and knowledge aspect was 41,53 %. Mind mapping makes logical thinking visible so that the quality of learning that has occurred can be seen and explored. Using mind mapping in the course of teaching means that learning is no longer a complex and intractable process, measurable is not only by proxy but also by an observable phenomenon.
[Progress in Application of Measuring Skeleton by CT in Forensic Anthropology Research].
Miao, C Y; Xu, L; Wang, N; Zhang, M; Li, Y S; Lü, J X
2017-02-01
Individual identification by measuring the human skeleton is an important research in the field of forensic anthropology. Computed tomography (CT) technology can provide high-resolution image of skeleton. Skeleton image can be reformed by software in the post-processing workstation. Different skeleton measurement indexes of anthropology, such as diameter, angle, area and volume, can be measured on section and reformative images. Measurement process is barely affected by human factors. This paper reviews the literatures at home and abroad about the application of measuring skeleton by CT in forensic anthropology research for individual identification in four aspects, including sex determination, height infer, facial soft tissue thickness measurement and age estimation. The major technology and the application of CT in forensic anthropology research are compared and discussed, respectively. Copyright© by the Editorial Department of Journal of Forensic Medicine.
Generic framework for vessel detection and tracking based on distributed marine radar image data
NASA Astrophysics Data System (ADS)
Siegert, Gregor; Hoth, Julian; Banyś, Paweł; Heymann, Frank
2018-04-01
Situation awareness is understood as a key requirement for safe and secure shipping at sea. The primary sensor for maritime situation assessment is still the radar, with the AIS being introduced as supplemental service only. In this article, we present a framework to assess the current situation picture based on marine radar image processing. Essentially, the framework comprises a centralized IMM-JPDA multi-target tracker in combination with a fully automated scheme for track management, i.e., target acquisition and track depletion. This tracker is conditioned on measurements extracted from radar images. To gain a more robust and complete situation picture, we are exploiting the aspect angle diversity of multiple marine radars, by fusing them a priori to the tracking process. Due to the generic structure of the proposed framework, different techniques for radar image processing can be implemented and compared, namely the BLOB detector and SExtractor. The overall framework performance in terms of multi-target state estimation will be compared for both methods based on a dedicated measurement campaign in the Baltic Sea with multiple static and mobile targets given.
Three-pass protocol scheme for bitmap image security by using vernam cipher algorithm
NASA Astrophysics Data System (ADS)
Rachmawati, D.; Budiman, M. A.; Aulya, L.
2018-02-01
Confidentiality, integrity, and efficiency are the crucial aspects of data security. Among the other digital data, image data is too prone to abuse of operation like duplication, modification, etc. There are some data security techniques, one of them is cryptography. The security of Vernam Cipher cryptography algorithm is very dependent on the key exchange process. If the key is leaked, security of this algorithm will collapse. Therefore, a method that minimizes key leakage during the exchange of messages is required. The method which is used, is known as Three-Pass Protocol. This protocol enables message delivery process without the key exchange. Therefore, the sending messages process can reach the receiver safely without fear of key leakage. The system is built by using Java programming language. The materials which are used for system testing are image in size 200×200 pixel, 300×300 pixel, 500×500 pixel, 800×800 pixel and 1000×1000 pixel. The result of experiments showed that Vernam Cipher algorithm in Three-Pass Protocol scheme could restore the original image.
Matrix phased array (MPA) imaging technology for resistance spot welds
NASA Astrophysics Data System (ADS)
Na, Jeong K.; Gleeson, Sean T.
2014-02-01
A three-dimensional MPA probe has been incorporated with a high speed phased array electronic board to visualize nugget images of resistance spot welds. The primary application area of this battery operated portable MPA ultrasonic imaging system is in the automotive industry which a conventional destructive testing process is commonly adopted to check the quality of resistance spot welds in auto bodies. Considering an average of five-thousand spot welds in a medium size passenger vehicle, the amount of time and effort given to popping the welds and measuring nugget size are immeasurable in addition to the millions of dollars' worth of scrap metals recycled per plant per year. This wasteful labor intensive destructive testing process has become less reliable as auto body sheet metal has transitioned from thick and heavy mild steels to thin and light high strength steels. Consequently, the necessity of developing a non-destructive inspection methodology has become inevitable. In this paper, the fundamental aspects of the current 3-D probe design, data acquisition algorithms, and weld nugget imaging process are discussed.
Matrix phased array (MPA) imaging technology for resistance spot welds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Na, Jeong K.; Gleeson, Sean T.
2014-02-18
A three-dimensional MPA probe has been incorporated with a high speed phased array electronic board to visualize nugget images of resistance spot welds. The primary application area of this battery operated portable MPA ultrasonic imaging system is in the automotive industry which a conventional destructive testing process is commonly adopted to check the quality of resistance spot welds in auto bodies. Considering an average of five-thousand spot welds in a medium size passenger vehicle, the amount of time and effort given to popping the welds and measuring nugget size are immeasurable in addition to the millions of dollars' worth ofmore » scrap metals recycled per plant per year. This wasteful labor intensive destructive testing process has become less reliable as auto body sheet metal has transitioned from thick and heavy mild steels to thin and light high strength steels. Consequently, the necessity of developing a non-destructive inspection methodology has become inevitable. In this paper, the fundamental aspects of the current 3-D probe design, data acquisition algorithms, and weld nugget imaging process are discussed.« less
Shedding of dual structures in the wake of a surface-mounted low aspect ratio cone
NASA Astrophysics Data System (ADS)
Chen, Zixiang; Martinuzzi, Robert J.
2018-04-01
The periodic shedding of vortex pairs in the turbulent wake of a surface-mounted right cone of aspect ratio 0.867 protruding a thin turbulent boundary layer is investigated experimentally. A phase-averaged volumetric velocity field is reconstructed from planar stereoscopic particle image velocimetry. During a typical (phase-averaged) shedding cycle, counter-rotating base vortices alternately form. These are tilted and stretched to merge with stream-wise tip vortices. The merged structure sheds and is convected downstream. A synthesis of earlier observations suggests that a similar shedding process exists for other low aspect ratio tapered geometries and is more complex than the shedding patterns observed for cantilevered cylinders, despite similarities of the mean flow field structure.
Diken, Mustafa; Pektor, Stefanie; Miederer, Matthias
2016-10-01
Preclinical imaging has become a powerful method for investigation of in vivo processes such as pharmacokinetics of therapeutic substances and visualization of physiologic and pathophysiological mechanisms. These are important aspects to understand diseases and develop strategies to modify their progression with pharmacologic interventions. One promising intervention is the application of specifically tailored nanoscale particles that modulate the immune system to generate a tumor targeting immune response. In this complex interaction between immunomodulatory therapies, the immune system and malignant disease, imaging methods are expected to play a key role on the way to generate new therapeutic strategies. Here, we summarize examples which demonstrate the current potential of imaging methods and develop a perspective on the future value of preclinical imaging of the immune system.
Three-dimensional near-field MIMO array imaging using range migration techniques.
Zhuge, Xiaodong; Yarovoy, Alexander G
2012-06-01
This paper presents a 3-D near-field imaging algorithm that is formulated for 2-D wideband multiple-input-multiple-output (MIMO) imaging array topology. The proposed MIMO range migration technique performs the image reconstruction procedure in the frequency-wavenumber domain. The algorithm is able to completely compensate the curvature of the wavefront in the near-field through a specifically defined interpolation process and provides extremely high computational efficiency by the application of the fast Fourier transform. The implementation aspects of the algorithm and the sampling criteria of a MIMO aperture are discussed. The image reconstruction performance and computational efficiency of the algorithm are demonstrated both with numerical simulations and measurements using 2-D MIMO arrays. Real-time 3-D near-field imaging can be achieved with a real-aperture array by applying the proposed MIMO range migration techniques.
A method to perform a fast fourier transform with primitive image transformations.
Sheridan, Phil
2007-05-01
The Fourier transform is one of the most important transformations in image processing. A major component of this influence comes from the ability to implement it efficiently on a digital computer. This paper describes a new methodology to perform a fast Fourier transform (FFT). This methodology emerges from considerations of the natural physical constraints imposed by image capture devices (camera/eye). The novel aspects of the specific FFT method described include: 1) a bit-wise reversal re-grouping operation of the conventional FFT is replaced by the use of lossless image rotation and scaling and 2) the usual arithmetic operations of complex multiplication are replaced with integer addition. The significance of the FFT presented in this paper is introduced by extending a discrete and finite image algebra, named Spiral Honeycomb Image Algebra (SHIA), to a continuous version, named SHIAC.
Fernández-Berni, Jorge; Carmona-Galán, Ricardo; del Río, Rocío; Kleihorst, Richard; Philips, Wilfried; Rodríguez-Vázquez, Ángel
2014-01-01
The capture, processing and distribution of visual information is one of the major challenges for the paradigm of the Internet of Things. Privacy emerges as a fundamental barrier to overcome. The idea of networked image sensors pervasively collecting data generates social rejection in the face of sensitive information being tampered by hackers or misused by legitimate users. Power consumption also constitutes a crucial aspect. Images contain a massive amount of data to be processed under strict timing requirements, demanding high-performance vision systems. In this paper, we describe a hardware-based strategy to concurrently address these two key issues. By conveying processing capabilities to the focal plane in addition to sensing, we can implement privacy protection measures just at the point where sensitive data are generated. Furthermore, such measures can be tailored for efficiently reducing the computational load of subsequent processing stages. As a proof of concept, a full-custom QVGA vision sensor chip is presented. It incorporates a mixed-signal focal-plane sensing-processing array providing programmable pixelation of multiple image regions in parallel. In addition to this functionality, the sensor exploits reconfigurability to implement other processing primitives, namely block-wise dynamic range adaptation, integral image computation and multi-resolution filtering. The proposed circuitry is also suitable to build a granular space, becoming the raw material for subsequent feature extraction and recognition of categorized objects. PMID:25195849
Fernández-Berni, Jorge; Carmona-Galán, Ricardo; del Río, Rocío; Kleihorst, Richard; Philips, Wilfried; Rodríguez-Vázquez, Ángel
2014-08-19
The capture, processing and distribution of visual information is one of the major challenges for the paradigm of the Internet of Things. Privacy emerges as a fundamental barrier to overcome. The idea of networked image sensors pervasively collecting data generates social rejection in the face of sensitive information being tampered by hackers or misused by legitimate users. Power consumption also constitutes a crucial aspect. Images contain a massive amount of data to be processed under strict timing requirements, demanding high-performance vision systems. In this paper, we describe a hardware-based strategy to concurrently address these two key issues. By conveying processing capabilities to the focal plane in addition to sensing, we can implement privacy protection measures just at the point where sensitive data are generated. Furthermore, such measures can be tailored for efficiently reducing the computational load of subsequent processing stages. As a proof of concept, a full-custom QVGA vision sensor chip is presented. It incorporates a mixed-signal focal-plane sensing-processing array providing programmable pixelation of multiple image regions in parallel. In addition to this functionality, the sensor exploits reconfigurability to implement other processing primitives, namely block-wise dynamic range adaptation, integral image computation and multi-resolution filtering. The proposed circuitry is also suitable to build a granular space, becoming the raw material for subsequent feature extraction and recognition of categorized objects.
Vision Algorithm for the Solar Aspect System of the HEROES Mission
NASA Technical Reports Server (NTRS)
Cramer, Alexander
2014-01-01
This work covers the design and test of a machine vision algorithm for generating high-accuracy pitch and yaw pointing solutions relative to the sun for the High Energy Replicated Optics to Explore the Sun (HEROES) mission. It describes how images were constructed by focusing an image of the sun onto a plate printed with a pattern of small fiducial markers. Images of this plate were processed in real time to determine relative position of the balloon payload to the sun. The algorithm is broken into four problems: circle detection, fiducial detection, fiducial identification, and image registration. Circle detection is handled by an "Average Intersection" method, fiducial detection by a matched filter approach, identification with an ad-hoc method based on the spacing between fiducials, and image registration with a simple least squares fit. Performance is verified on a combination of artificially generated images, test data recorded on the ground, and images from the 2013 flight
Vision Algorithm for the Solar Aspect System of the HEROES Mission
NASA Technical Reports Server (NTRS)
Cramer, Alexander; Christe, Steven; Shih, Albert
2014-01-01
This work covers the design and test of a machine vision algorithm for generating high-accuracy pitch and yaw pointing solutions relative to the sun for the High Energy Replicated Optics to Explore the Sun (HEROES) mission. It describes how images were constructed by focusing an image of the sun onto a plate printed with a pattern of small fiducial markers. Images of this plate were processed in real time to determine relative position of the balloon payload to the sun. The algorithm is broken into four problems: circle detection, fiducial detection, fiducial identification, and image registration. Circle detection is handled by an Average Intersection method, fiducial detection by a matched filter approach, identification with an ad-hoc method based on the spacing between fiducials, and image registration with a simple least squares fit. Performance is verified on a combination of artificially generated images, test data recorded on the ground, and images from the 2013 flight.
Molecular aspects of magnetic resonance imaging and spectroscopy.
Boesch, C
1999-01-01
Magnetic resonance imaging (MRI) is a well known diagnostic tool in radiology that produces unsurpassed images of the human body, in particular of soft tissue. However, the medical community is often not aware that MRI is an important yet limited segment of magnetic resonance (MR) or nuclear magnetic resonance (NMR) as this method is called in basic science. The tremendous morphological information of MR images sometimes conceal the fact that MR signals in general contain much more information, especially on processes on the molecular level. NMR is successfully used in physics, chemistry, and biology to explore and characterize chemical reactions, molecular conformations, biochemical pathways, solid state material, and many other applications that elucidate invisible characteristics of matter and tissue. In medical applications, knowledge of the molecular background of MRI and in particular MR spectroscopy (MRS) is an inevitable basis to understand molecular phenomenon leading to macroscopic effects visible in diagnostic images or spectra. This review shall provide the necessary background to comprehend molecular aspects of magnetic resonance applications in medicine. An introduction into the physical basics aims at an understanding of some of the molecular mechanisms without extended mathematical treatment. The MR typical terminology is explained such that reading of original MR publications could be facilitated for non-MR experts. Applications in MRI and MRS are intended to illustrate the consequences of molecular effects on images and spectra.
Wear Detection of Drill Bit by Image-based Technique
NASA Astrophysics Data System (ADS)
Sukeri, Maziyah; Zulhilmi Paiz Ismadi, Mohd; Rahim Othman, Abdul; Kamaruddin, Shahrul
2018-03-01
Image processing for computer vision function plays an essential aspect in the manufacturing industries for the tool condition monitoring. This study proposes a dependable direct measurement method to measure the tool wear using image-based analysis. Segmentation and thresholding technique were used as the means to filter and convert the colour image to binary datasets. Then, the edge detection method was applied to characterize the edge of the drill bit. By using cross-correlation method, the edges of original and worn drill bits were correlated to each other. Cross-correlation graphs were able to detect the difference of the worn edge despite small difference between the graphs. Future development will focus on quantifying the worn profile as well as enhancing the sensitivity of the technique.
Effects of relative embodiment in lexical and semantic processing of verbs.
Sidhu, David M; Kwan, Rachel; Pexman, Penny M; Siakaluk, Paul D
2014-06-01
Research examining semantic richness effects in visual word recognition has shown that multiple dimensions of meaning are activated in the process of word recognition (e.g., Yap et al., 2012). This research has, however, been limited to nouns. In the present research we extended the semantic richness approach to verb stimuli in order to investigate how verb meanings are represented. We characterized a dimension of relative embodiment for verbs, based on the bodily sense described by Borghi and Cimatti (2010), and collected ratings on that dimension for 687 English verbs. The relative embodiment ratings revealed that bodily experience was judged to be more important to the meanings of some verbs (e.g., dance, breathe) than to others (e.g., evaporate, expect). We then tested the effects of relative embodiment and imageability on verb processing in lexical decision (Experiment 1), action picture naming (Experiment 2), and syntactic classification (Experiment 3). In all three experiments results showed facilitatory effects of relative embodiment, but not imageability: latencies were faster for relatively more embodied verbs, even after several other lexical variables were controlled. The results suggest that relative embodiment is an important aspect of verb meaning, and that the semantic richness approach holds promise as a strategy for investigating other aspects of verb meaning. Copyright © 2014 Elsevier B.V. All rights reserved.
Destructive Dialogue: Negative Self-Talk and Effective Imaging.
ERIC Educational Resources Information Center
Weaver, Richard L., II; Cotrell, Howard W.
Destructive dialogue, originating from frustration and disappointment, is an intrapersonal process that always involves a person in a relationship to others and that can be defined as inner talk cast in a negative tone. It is so powerful, influential, and pervasive that it can affect all aspects of a person's life and become a self-fulfilling…
Local area networks in an imaging environment.
Noz, M E; Maguire, G Q; Erdman, W A
1986-01-01
There is great interest at present in incorporating image-management systems popularly referred to as picture archiving and communication systems (PACS) into imaging departments. This paper will describe various aspects of local area networks (LANs) for medical images and will give a definition of terms and classification of devices by describing a possible system which links various digital image sources through a high-speed data link and a common image format, allows for viewing and processing of all images produced within the complex, and eliminates the transport of films. The status of standards governing LAN and particularly PACS systems along with a proposed image exchange format will be given. Prototype systems, particularly a system for nuclear medicine images, will be presented, as well as the prospects for the immediate future in terms of installations started and commercial products available. A survey of the many questions that arise in the development of a PACS for medical images and also a survey of the presently suggested/adopted answers will be given.
On-road anomaly detection by multimodal sensor analysis and multimedia processing
NASA Astrophysics Data System (ADS)
Orhan, Fatih; Eren, P. E.
2014-03-01
The use of smartphones in Intelligent Transportation Systems is gaining popularity, yet many challenges exist in developing functional applications. Due to the dynamic nature of transportation, vehicular social applications face complexities such as developing robust sensor management, performing signal and image processing tasks, and sharing information among users. This study utilizes a multimodal sensor analysis framework which enables the analysis of sensors in multimodal aspect. It also provides plugin-based analyzing interfaces to develop sensor and image processing based applications, and connects its users via a centralized application as well as to social networks to facilitate communication and socialization. With the usage of this framework, an on-road anomaly detector is being developed and tested. The detector utilizes the sensors of a mobile device and is able to identify anomalies such as hard brake, pothole crossing, and speed bump crossing. Upon such detection, the video portion containing the anomaly is automatically extracted in order to enable further image processing analysis. The detection results are shared on a central portal application for online traffic condition monitoring.
Flavel, Richard J; Guppy, Chris N; Rabbi, Sheikh M R; Young, Iain M
2017-01-01
The objective of this study was to develop a flexible and free image processing and analysis solution, based on the Public Domain ImageJ platform, for the segmentation and analysis of complex biological plant root systems in soil from x-ray tomography 3D images. Contrasting root architectures from wheat, barley and chickpea root systems were grown in soil and scanned using a high resolution micro-tomography system. A macro (Root1) was developed that reliably identified with good to high accuracy complex root systems (10% overestimation for chickpea, 1% underestimation for wheat, 8% underestimation for barley) and provided analysis of root length and angle. In-built flexibility allowed the user interaction to (a) amend any aspect of the macro to account for specific user preferences, and (b) take account of computational limitations of the platform. The platform is free, flexible and accurate in analysing root system metrics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perrine, Kenneth A.; Hopkins, Derek F.; Lamarche, Brian L.
2005-09-01
Biologists and computer engineers at Pacific Northwest National Laboratory have specified, designed, and implemented a hardware/software system for performing real-time, multispectral image processing on a confocal microscope. This solution is intended to extend the capabilities of the microscope, enabling scientists to conduct advanced experiments on cell signaling and other kinds of protein interactions. FRET (fluorescence resonance energy transfer) techniques are used to locate and monitor protein activity. In FRET, it is critical that spectral images be precisely aligned with each other despite disturbances in the physical imaging path caused by imperfections in lenses and cameras, and expansion and contraction ofmore » materials due to temperature changes. The central importance of this work is therefore automatic image registration. This runs in a framework that guarantees real-time performance (processing pairs of 1024x1024, 8-bit images at 15 frames per second) and enables the addition of other types of advanced image processing algorithms such as image feature characterization. The supporting system architecture consists of a Visual Basic front-end containing a series of on-screen interfaces for controlling various aspects of the microscope and a script engine for automation. One of the controls is an ActiveX component written in C++ for handling the control and transfer of images. This component interfaces with a pair of LVDS image capture boards and a PCI board containing a 6-million gate Xilinx Virtex-II FPGA. Several types of image processing are performed on the FPGA in a pipelined fashion, including the image registration. The FPGA offloads work that would otherwise need to be performed by the main CPU and has a guaranteed real-time throughput. Image registration is performed in the FPGA by applying a cubic warp on one image to precisely align it with the other image. Before each experiment, an automated calibration procedure is run in order to set up the cubic warp. During image acquisitions, the cubic warp is evaluated by way of forward differencing. Unwanted pixelation artifacts are minimized by bilinear sampling. The resulting system is state-of-the-art for biological imaging. Precisely registered images enable the reliable use of FRET techniques. In addition, real-time image processing performance allows computed images to be fed back and displayed to scientists immediately, and the pipelined nature of the FPGA allows additional image processing algorithms to be incorporated into the system without slowing throughput.« less
A Versatile Mounting Method for Long Term Imaging of Zebrafish Development.
Hirsinger, Estelle; Steventon, Ben
2017-01-26
Zebrafish embryos offer an ideal experimental system to study complex morphogenetic processes due to their ease of accessibility and optical transparency. In particular, posterior body elongation is an essential process in embryonic development by which multiple tissue deformations act together to direct the formation of a large part of the body axis. In order to observe this process by long-term time-lapse imaging it is necessary to utilize a mounting technique that allows sufficient support to maintain samples in the correct orientation during transfer to the microscope and acquisition. In addition, the mounting must also provide sufficient freedom of movement for the outgrowth of the posterior body region without affecting its normal development. Finally, there must be a certain degree in versatility of the mounting method to allow imaging on diverse imaging set-ups. Here, we present a mounting technique for imaging the development of posterior body elongation in the zebrafish D. rerio. This technique involves mounting embryos such that the head and yolk sac regions are almost entirely included in agarose, while leaving out the posterior body region to elongate and develop normally. We will show how this can be adapted for upright, inverted and vertical light-sheet microscopy set-ups. While this protocol focuses on mounting embryos for imaging for the posterior body, it could easily be adapted for the live imaging of multiple aspects of zebrafish development.
Text analysis devices, articles of manufacture, and text analysis methods
Turner, Alan E; Hetzler, Elizabeth G; Nakamura, Grant C
2015-03-31
Text analysis devices, articles of manufacture, and text analysis methods are described according to some aspects. In one aspect, a text analysis device includes a display configured to depict visible images, and processing circuitry coupled with the display and wherein the processing circuitry is configured to access a first vector of a text item and which comprises a plurality of components, to access a second vector of the text item and which comprises a plurality of components, to weight the components of the first vector providing a plurality of weighted values, to weight the components of the second vector providing a plurality of weighted values, and to combine the weighted values of the first vector with the weighted values of the second vector to provide a third vector.
PIZZARO: Forensic analysis and restoration of image and video data.
Kamenicky, Jan; Bartos, Michal; Flusser, Jan; Mahdian, Babak; Kotera, Jan; Novozamsky, Adam; Saic, Stanislav; Sroubek, Filip; Sorel, Michal; Zita, Ales; Zitova, Barbara; Sima, Zdenek; Svarc, Petr; Horinek, Jan
2016-07-01
This paper introduces a set of methods for image and video forensic analysis. They were designed to help to assess image and video credibility and origin and to restore and increase image quality by diminishing unwanted blur, noise, and other possible artifacts. The motivation came from the best practices used in the criminal investigation utilizing images and/or videos. The determination of the image source, the verification of the image content, and image restoration were identified as the most important issues of which automation can facilitate criminalists work. Novel theoretical results complemented with existing approaches (LCD re-capture detection and denoising) were implemented in the PIZZARO software tool, which consists of the image processing functionality as well as of reporting and archiving functions to ensure the repeatability of image analysis procedures and thus fulfills formal aspects of the image/video analysis work. Comparison of new proposed methods with the state of the art approaches is shown. Real use cases are presented, which illustrate the functionality of the developed methods and demonstrate their applicability in different situations. The use cases as well as the method design were solved in tight cooperation of scientists from the Institute of Criminalistics, National Drug Headquarters of the Criminal Police and Investigation Service of the Police of the Czech Republic, and image processing experts from the Czech Academy of Sciences. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Henderson, Fiona; Hart, Philippa J; Pradillo, Jesus M; Kassiou, Michael; Christie, Lidan; Williams, Kaye J; Boutin, Herve; McMahon, Adam
2018-05-15
Stroke is a leading cause of disability worldwide. Understanding the recovery process post-stroke is essential; however, longer-term recovery studies are lacking. In vivo positron emission tomography (PET) can image biological recovery processes, but is limited by spatial resolution and its targeted nature. Untargeted mass spectrometry imaging offers high spatial resolution, providing an ideal ex vivo tool for brain recovery imaging. Magnetic resonance imaging (MRI) was used to image a rat brain 48 h after ischaemic stroke to locate the infarcted regions of the brain. PET was carried out 3 months post-stroke using the tracers [ 18 F]DPA-714 for TSPO and [ 18 F]IAM6067 for sigma-1 receptors to image neuroinflammation and neurodegeneration, respectively. The rat brain was flash-frozen immediately after PET scanning, and sectioned for matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) imaging. Three months post-stroke, PET imaging shows minimal detection of neurodegeneration and neuroinflammation, indicating that the brain has stabilised. However, MALDI-MS images reveal distinct differences in lipid distributions (e.g. phosphatidylcholine and sphingomyelin) between the scar and the healthy brain, suggesting that recovery processes are still in play. It is currently not known if the altered lipids in the scar will change on a longer time scale, or if they are stabilised products of the brain post-stroke. The data demonstrates the ability to combine MALD-MS with in vivo PET to image different aspects of stroke recovery. Copyright © 2018 John Wiley & Sons, Ltd.
Magnetic resonance imaging of live freshwater mussels (Unionidae)
Michael, Holliman F.; Davis, Denise; Bogan, Arthur E.; Kwak, Thomas J.; Cope, W. Gregory; Levine, Jay F.
2008-01-01
We examined the soft tissues of live freshwater mussels, Eastern elliptio Elliptio complanata, via magnetic resonance imaging (MRI), acquiring data with a widely available human whole-body MRI system. Anatomical features depicted in the profile images included the foot, stomach, intestine, anterior and posterior adductor muscles, and pericardial cavity. Noteworthy observations on soft tissue morphology included a concentration of lipids at the most posterior aspect of the foot, the presence of hemolymph-filled fissures in the posterior adductor muscle, the presence of a relatively large hemolymph-filled sinus adjacent to the posterior adductor muscle (at the ventral-anterior aspect), and segmentation of the intestine (a diagnostic description not reported previously in Unionidae). Relatively little is known about the basic biology and ecological physiology of freshwater mussels. Traditional approaches for studying anatomy and tissue processes, and for measuring sub-lethal physiological stress, are destructive or invasive. Our study, the first to evaluate freshwater mussel soft tissues by MRI, clarifies the body plan of unionid mussels and demonstrates the efficacy of this technology for in vivoevaluation of the structure, function, and integrity of mussel soft tissues.
Complementary aspects of diffusion imaging and fMRI; I: structure and function.
Mulkern, Robert V; Davis, Peter E; Haker, Steven J; Estepar, Raul San Jose; Panych, Lawrence P; Maier, Stephan E; Rivkin, Michael J
2006-05-01
Studying the intersection of brain structure and function is an important aspect of modern neuroscience. The development of magnetic resonance imaging (MRI) over the last 25 years has provided new and powerful tools for the study of brain structure and function. Two tools in particular, diffusion imaging and functional MRI (fMRI), are playing increasingly important roles in elucidating the complementary aspects of brain structure and function. In this work, we review basic technical features of diffusion imaging and fMRI for studying the integrity of white matter structural components and for determining the location and extent of cortical activation in gray matter, respectively. We then review a growing body of literature in which the complementary aspects of diffusion imaging and fMRI, applied as separate examinations but analyzed in tandem, have been exploited to enhance our knowledge of brain structure and function.
Dissociation between melodic and rhythmic processing during piano performance from musical scores.
Bengtsson, Sara L; Ullén, Fredrik
2006-03-01
When performing or perceiving music, we experience the melodic (spatial) and rhythmic aspects as a unified whole. Moreover, the motor program theory stipulates that the relative timing and the serial order of the movement are invariant features of a motor program. Still, clinical and psychophysical observations suggest independent processing of these two aspects, in both production and perception. Here, we used functional magnetic resonance imaging to dissociate between brain areas processing the melodic and the rhythmic aspects during piano playing from musical scores. This behavior requires that the pianist decodes two types of information from the score in order to produce the desired piece of music. The spatial location of a note head determines which piano key to strike, and the various features of the note, such as the stem and flags determine the timing of each key stroke. We found that the medial occipital lobe, the superior temporal lobe, the rostral cingulate cortex, the putamen and the cerebellum process the melodic information, whereas the lateral occipital and the inferior temporal cortex, the left supramarginal gyrus, the left inferior and ventral frontal gyri, the caudate nucleus, and the cerebellum process the rhythmic information. Thus, we suggest a dissociate involvement of the dorsal visual stream in the spatial pitch processing and the ventral visual stream in temporal movement preparation. We propose that this dissociate organization may be important for fast learning and flexibility in motor control.
NASA Astrophysics Data System (ADS)
Bianchetti, Raechel Anne
Remotely sensed images have become a ubiquitous part of our daily lives. From novice users, aiding in search and rescue missions using tools such as TomNod, to trained analysts, synthesizing disparate data to address complex problems like climate change, imagery has become central to geospatial problem solving. Expert image analysts are continually faced with rapidly developing sensor technologies and software systems. In response to these cognitively demanding environments, expert analysts develop specialized knowledge and analytic skills to address increasingly complex problems. This study identifies the knowledge, skills, and analytic goals of expert image analysts tasked with identification of land cover and land use change. Analysts participating in this research are currently working as part of a national level analysis of land use change, and are well versed with the use of TimeSync, forest science, and image analysis. The results of this study benefit current analysts as it improves their awareness of their mental processes used during the image interpretation process. The study also can be generalized to understand the types of knowledge and visual cues that analysts use when reasoning with imagery for purposes beyond land use change studies. Here a Cognitive Task Analysis framework is used to organize evidence from qualitative knowledge elicitation methods for characterizing the cognitive aspects of the TimeSync image analysis process. Using a combination of content analysis, diagramming, semi-structured interviews, and observation, the study highlights the perceptual and cognitive elements of expert remote sensing interpretation. Results show that image analysts perform several standard cognitive processes, but flexibly employ these processes in response to various contextual cues. Expert image analysts' ability to think flexibly during their analysis process was directly related to their amount of image analysis experience. Additionally, results show that the basic Image Interpretation Elements continue to be important despite technological augmentation of the interpretation process. These results are used to derive a set of design guidelines for developing geovisual analytic tools and training to support image analysis.
Generalized ISAR--part I: an optimal method for imaging large naval vessels.
Given, James A; Schmidt, William R
2005-11-01
We describe a generalized inverse synthetic aperture radar (ISAR) process that performs well under a wide variety of conditions common to the naval ISAR tests of large vessels. In particular, the generalized ISAR process performs well in the presence of moderate intensity ship roll. The process maps localized scatterers onto peaks on the ISAR plot. However, in a generalized ISAR plot, each of the two coordinates of a peak is a fixed linear combination of the three ship coordinates of the scatterer causing the peak. Combining this process with interferometry will then provide high-accuracy three-dimensional location of the important scatterers on a ship. We show that ISAR can be performed in the presence of simultaneous roll and aspect change, provided the two Doppler rates are not too close in magnitude. We derive the equations needed for generalized ISAR, both roll driven and aspect driven, and test them against simulations performed in a variety of conditions, including large roll amplitudes.
A pipeline for comprehensive and automated processing of electron diffraction data in IPLT.
Schenk, Andreas D; Philippsen, Ansgar; Engel, Andreas; Walz, Thomas
2013-05-01
Electron crystallography of two-dimensional crystals allows the structural study of membrane proteins in their native environment, the lipid bilayer. Determining the structure of a membrane protein at near-atomic resolution by electron crystallography remains, however, a very labor-intense and time-consuming task. To simplify and accelerate the data processing aspect of electron crystallography, we implemented a pipeline for the processing of electron diffraction data using the Image Processing Library and Toolbox (IPLT), which provides a modular, flexible, integrated, and extendable cross-platform, open-source framework for image processing. The diffraction data processing pipeline is organized as several independent modules implemented in Python. The modules can be accessed either from a graphical user interface or through a command line interface, thus meeting the needs of both novice and expert users. The low-level image processing algorithms are implemented in C++ to achieve optimal processing performance, and their interface is exported to Python using a wrapper. For enhanced performance, the Python processing modules are complemented with a central data managing facility that provides a caching infrastructure. The validity of our data processing algorithms was verified by processing a set of aquaporin-0 diffraction patterns with the IPLT pipeline and comparing the resulting merged data set with that obtained by processing the same diffraction patterns with the classical set of MRC programs. Copyright © 2013 Elsevier Inc. All rights reserved.
A pipeline for comprehensive and automated processing of electron diffraction data in IPLT
Schenk, Andreas D.; Philippsen, Ansgar; Engel, Andreas; Walz, Thomas
2013-01-01
Electron crystallography of two-dimensional crystals allows the structural study of membrane proteins in their native environment, the lipid bilayer. Determining the structure of a membrane protein at near-atomic resolution by electron crystallography remains, however, a very labor-intense and time-consuming task. To simplify and accelerate the data processing aspect of electron crystallography, we implemented a pipeline for the processing of electron diffraction data using the Image Processing Library & Toolbox (IPLT), which provides a modular, flexible, integrated, and extendable cross-platform, open-source framework for image processing. The diffraction data processing pipeline is organized as several independent modules implemented in Python. The modules can be accessed either from a graphical user interface or through a command line interface, thus meeting the needs of both novice and expert users. The low-level image processing algorithms are implemented in C++ to achieve optimal processing performance, and their interface is exported to Python using a wrapper. For enhanced performance, the Python processing modules are complemented with a central data managing facility that provides a caching infrastructure. The validity of our data processing algorithms was verified by processing a set of aquaporin-0 diffraction patterns with the IPLT pipeline and comparing the resulting merged data set with that obtained by processing the same diffraction patterns with the classical set of MRC programs. PMID:23500887
Iyappan, Anandhi; Younesi, Erfan; Redolfi, Alberto; Vrooman, Henri; Khanna, Shashank; Frisoni, Giovanni B.; Hofmann-Apitius, Martin
2017-01-01
Ontologies and terminologies are used for interoperability of knowledge and data in a standard manner among interdisciplinary research groups. Existing imaging ontologies capture general aspects of the imaging domain as a whole such as methodological concepts or calibrations of imaging instruments. However, none of the existing ontologies covers the diagnostic features measured by imaging technologies in the context of neurodegenerative diseases. Therefore, the Neuro-Imaging Feature Terminology (NIFT) was developed to organize the knowledge domain of measured brain features in association with neurodegenerative diseases by imaging technologies. The purpose is to identify quantitative imaging biomarkers that can be extracted from multi-modal brain imaging data. This terminology attempts to cover measured features and parameters in brain scans relevant to disease progression. In this paper, we demonstrate the systematic retrieval of measured indices from literature and how the extracted knowledge can be further used for disease modeling that integrates neuroimaging features with molecular processes. PMID:28731430
Interactive degraded document enhancement and ground truth generation
NASA Astrophysics Data System (ADS)
Bal, G.; Agam, G.; Frieder, O.; Frieder, G.
2008-01-01
Degraded documents are frequently obtained in various situations. Examples of degraded document collections include historical document depositories, document obtained in legal and security investigations, and legal and medical archives. Degraded document images are hard to to read and are hard to analyze using computerized techniques. There is hence a need for systems that are capable of enhancing such images. We describe a language-independent semi-automated system for enhancing degraded document images that is capable of exploiting inter- and intra-document coherence. The system is capable of processing document images with high levels of degradations and can be used for ground truthing of degraded document images. Ground truthing of degraded document images is extremely important in several aspects: it enables quantitative performance measurements of enhancement systems and facilitates model estimation that can be used to improve performance. Performance evaluation is provided using the historical Frieder diaries collection.1
Mining biomedical images towards valuable information retrieval in biomedical and life sciences
Ahmed, Zeeshan; Zeeshan, Saman; Dandekar, Thomas
2016-01-01
Biomedical images are helpful sources for the scientists and practitioners in drawing significant hypotheses, exemplifying approaches and describing experimental results in published biomedical literature. In last decades, there has been an enormous increase in the amount of heterogeneous biomedical image production and publication, which results in a need for bioimaging platforms for feature extraction and analysis of text and content in biomedical images to take advantage in implementing effective information retrieval systems. In this review, we summarize technologies related to data mining of figures. We describe and compare the potential of different approaches in terms of their developmental aspects, used methodologies, produced results, achieved accuracies and limitations. Our comparative conclusions include current challenges for bioimaging software with selective image mining, embedded text extraction and processing of complex natural language queries. PMID:27538578
Interdepartmental conflict management and negotiation in cardiovascular imaging.
Otero, Hansel J; Nallamshetty, Leelakrishna; Rybicki, Frank J
2008-07-01
Although the relationship between cardiologists and radiologists has a thorny history, advanced cardiac imaging technology and the promise of cardiac computed tomography are forcing both specialties back to the negotiation table. These discussions represent an opportunity for better communication, collaboration, and resource allocation. The authors address the aspects of interdepartmental conflict management and negotiation through their radiology department's ongoing efforts to provide high-quality advanced noninvasive cardiovascular imaging services at a large academic institution. The definition and causes of conflict are defined, with a specific focus on noninvasive cardiovascular imaging, followed by a description of steps used in the negotiation process. The authors encourage radiologists to entertain an open dialogue with cardiology, because in many cases, both sides can benefit. The benefits of a negotiated outcome include minimizing internal competitors, incorporating cardiologists' expertise to cardiac imaging algorithms, and more effective training opportunities.
3D Lunar Terrain Reconstruction from Apollo Images
NASA Technical Reports Server (NTRS)
Broxton, Michael J.; Nefian, Ara V.; Moratto, Zachary; Kim, Taemin; Lundy, Michael; Segal, Alkeksandr V.
2009-01-01
Generating accurate three dimensional planetary models is becoming increasingly important as NASA plans manned missions to return to the Moon in the next decade. This paper describes a 3D surface reconstruction system called the Ames Stereo Pipeline that is designed to produce such models automatically by processing orbital stereo imagery. We discuss two important core aspects of this system: (1) refinement of satellite station positions and pose estimates through least squares bundle adjustment; and (2) a stochastic plane fitting algorithm that generalizes the Lucas-Kanade method for optimal matching between stereo pair images.. These techniques allow us to automatically produce seamless, highly accurate digital elevation models from multiple stereo image pairs while significantly reducing the influence of image noise. Our technique is demonstrated on a set of 71 high resolution scanned images from the Apollo 15 mission
Characterizing challenged Minnesota ballots
NASA Astrophysics Data System (ADS)
Nagy, George; Lopresti, Daniel; Barney Smith, Elisa H.; Wu, Ziyan
2011-01-01
Photocopies of the ballots challenged in the 2008 Minnesota elections, which constitute a public record, were scanned on a high-speed scanner and made available on a public radio website. The PDF files were downloaded, converted to TIF images, and posted on the PERFECT website. Based on a review of relevant image-processing aspects of paper-based election machinery and on additional statistics and observations on the posted sample data, robust tools were developed for determining the underlying grid of the targets on these ballots regardless of skew, clipping, and other degradations caused by high-speed copying and digitization. The accuracy and robustness of a method based on both index-marks and oval targets are demonstrated on 13,435 challenged ballot page images.
Kuniecki, Michał; Wołoszyn, Kinga; Domagalik, Aleksandra; Pilarczyk, Joanna
2018-05-01
Processing of emotional visual information engages cognitive functions and induces arousal. We aimed to examine the modulatory role of emotional valence on brain activations linked to the processing of visual information and those linked to arousal. Participants were scanned and their pupil size was measured while viewing negative and neutral images. The visual noise was added to the images in various proportions to parametrically manipulate the amount of visual information. Pupil size was used as an index of physiological arousal. We show that arousal induced by the negative images, as compared to the neutral ones, is primarily related to greater amygdala activity while increasing visibility of negative content to enhanced activity in the lateral occipital complex (LOC). We argue that more intense visual processing of negative scenes can occur irrespective of the level of arousal. It may suggest that higher areas of the visual stream are fine-tuned to process emotionally relevant objects. Both arousal and processing of emotional visual information modulated activity within the ventromedial prefrontal cortex (vmPFC). Overlapping activations within the vmPFC may reflect the integration of these aspects of emotional processing. Additionally, we show that emotionally-evoked pupil dilations are related to activations in the amygdala, vmPFC, and LOC.
Wavelet-Based Signal and Image Processing for Target Recognition
NASA Astrophysics Data System (ADS)
Sherlock, Barry G.
2002-11-01
The PI visited NSWC Dahlgren, VA, for six weeks in May-June 2002 and collaborated with scientists in the G33 TEAMS facility, and with Marilyn Rudzinsky of T44 Technology and Photonic Systems Branch. During this visit the PI also presented six educational seminars to NSWC scientists on various aspects of signal processing. Several items from the grant proposal were completed, including (1) wavelet-based algorithms for interpolation of 1-d signals and 2-d images; (2) Discrete Wavelet Transform domain based algorithms for filtering of image data; (3) wavelet-based smoothing of image sequence data originally obtained for the CRITTIR (Clutter Rejection Involving Temporal Techniques in the Infra-Red) project. The PI visited the University of Stellenbosch, South Africa to collaborate with colleagues Prof. B.M. Herbst and Prof. J. du Preez on the use of wavelet image processing in conjunction with pattern recognition techniques. The University of Stellenbosch has offered the PI partial funding to support a sabbatical visit in Fall 2003, the primary purpose of which is to enable the PI to develop and enhance his expertise in Pattern Recognition. During the first year, the grant supported publication of 3 referred papers, presentation of 9 seminars and an intensive two-day course on wavelet theory. The grant supported the work of two students who functioned as research assistants.
ERIC Educational Resources Information Center
Kohaupt, Ludwig
2015-01-01
The discrete Fourier series is a valuable tool developed and used by mathematicians and engineers alike. One of the most prominent applications is signal processing. Usually, it is important that the signals be transmitted fast, for example, when transmitting images over large distances such as between the moon and the earth or when generating…
Challenges for data storage in medical imaging research.
Langer, Steve G
2011-04-01
Researchers in medical imaging have multiple challenges for storing, indexing, maintaining viability, and sharing their data. Addressing all these concerns requires a constellation of tools, but not all of them need to be local to the site. In particular, the data storage challenges faced by researchers can begin to require professional information technology skills. With limited human resources and funds, the medical imaging researcher may be better served with an outsourcing strategy for some management aspects. This paper outlines an approach to manage the main objectives faced by medical imaging scientists whose work includes processing and data mining on non-standard file formats, and relating those files to the their DICOM standard descendents. The capacity of the approach scales as the researcher's need grows by leveraging the on-demand provisioning ability of cloud computing.
Use of multidimensional, multimodal imaging and PACS to support neurological diagnoses
NASA Astrophysics Data System (ADS)
Wong, Stephen T. C.; Knowlton, Robert C.; Hoo, Kent S.; Huang, H. K.
1995-05-01
Technological advances in brain imaging have revolutionized diagnosis in neurology and neurological surgery. Major imaging techniques include magnetic resonance imaging (MRI) to visualize structural anatomy, positron emission tomography (PET) to image metabolic function and cerebral blood flow, magnetoencephalography (MEG) to visualize the location of physiologic current sources, and magnetic resonance spectroscopy (MRS) to measure specific biochemicals. Each of these techniques studies different biomedical aspects of the brain, but there lacks an effective means to quantify and correlate the disparate imaging datasets in order to improve clinical decision making processes. This paper describes several techniques developed in a UNIX-based neurodiagnostic workstation to aid the noninvasive presurgical evaluation of epilepsy patients. These techniques include online access to the picture archiving and communication systems (PACS) multimedia archive, coregistration of multimodality image datasets, and correlation and quantitation of structural and functional information contained in the registered images. For illustration, we describe the use of these techniques in a patient case of nonlesional neocortical epilepsy. We also present out future work based on preliminary studies.
Integration of medical imaging into a multi-institutional hospital information system structure.
Dayhoff, R E
1995-01-01
The Department of Veterans Affairs (VA) is providing integrated text and image data to its clinical users at its Washington and Baltimore medical centers and, soon, at nine other medical centers. The DHCP Imaging System records clinically significant diagnostic images selected by medical specialists in a variety of departments, including cardiology, gastroenterology, pathology, dermatology, surgery, radiology, podiatry, dentistry, and emergency medicine. These images, which include color and gray scale images, and electrocardiogram waveforms, are displayed on workstations located throughout the medical centers. Integration of clinical images with the VA's electronic mail system allows transfer of data from one medical center to another. The ability to incorporate transmitted text and image data into on-line patient records at the collaborating sites is an important aspect of professional consultation. In order to achieve the maximum benefits from an integrated patient record system, a critical mass of information must be available for clinicians. When there is also seamless support for administration, it becomes possible to re-engineer the processes involved in providing medical care.
Chhatbar, Pratik Y.; Kara, Prakash
2013-01-01
Neural activity leads to hemodynamic changes which can be detected by functional magnetic resonance imaging (fMRI). The determination of blood flow changes in individual vessels is an important aspect of understanding these hemodynamic signals. Blood flow can be calculated from the measurements of vessel diameter and blood velocity. When using line-scan imaging, the movement of blood in the vessel leads to streaks in space-time images, where streak angle is a function of the blood velocity. A variety of methods have been proposed to determine blood velocity from such space-time image sequences. Of these, the Radon transform is relatively easy to implement and has fast data processing. However, the precision of the velocity measurements is dependent on the number of Radon transforms performed, which creates a trade-off between the processing speed and measurement precision. In addition, factors like image contrast, imaging depth, image acquisition speed, and movement artifacts especially in large mammals, can potentially lead to data acquisition that results in erroneous velocity measurements. Here we show that pre-processing the data with a Sobel filter and iterative application of Radon transforms address these issues and provide more accurate blood velocity measurements. Improved signal quality of the image as a result of Sobel filtering increases the accuracy and the iterative Radon transform offers both increased precision and an order of magnitude faster implementation of velocity measurements. This algorithm does not use a priori knowledge of angle information and therefore is sensitive to sudden changes in blood flow. It can be applied on any set of space-time images with red blood cell (RBC) streaks, commonly acquired through line-scan imaging or reconstructed from full-frame, time-lapse images of the vasculature. PMID:23807877
Lee, In-Seon; Preissl, Hubert; Giel, Katrin; Schag, Kathrin; Enck, Paul
2018-01-23
The food-related behavior of functional dyspepsia has been attracting more interest of late. This pilot study aims to provide evidence of the physiological, emotional, and attentional aspects of food processing in functional dyspepsia patients. The study was performed in 15 functional dyspepsia patients and 17 healthy controls after a standard breakfast. We measured autonomic nervous system activity using skin conductance response and heart rate variability, emotional response using facial electromyography, and visual attention using eyetracking during the visual stimuli of food/non-food images. In comparison to healthy controls, functional dyspepsia patients showed a greater craving for food, a decreased intake of food, more dyspeptic symptoms, lower pleasantness rating of food images (particularly of high fat), decreased low frequency/high frequency ratio of heart rate variability, and suppressed total processing time of food images. There were no significant differences of skin conductance response and facial electromyography data between groups. The results suggest that high level cognitive functions rather than autonomic and emotional mechanisms are more liable to function differently in functional dyspepsia patients. Abnormal dietary behavior, reduced subjective rating of pleasantness and visual attention to food should be considered as important pathophysiological characteristics in functional dyspepsia.
Advantages and disadvantages of computer imaging in cosmetic surgery.
Koch, R J; Chavez, A; Dagum, P; Newman, J P
1998-02-01
Despite the growing popularity of computer imaging systems, it is not clear whether the medical and legal advantages of using such a system outweigh the disadvantages. The purpose of this report is to evaluate these aspects, and provide some protective guidelines in the use of computer imaging in cosmetic surgery. The positive and negative aspects of computer imaging from a medical and legal perspective are reviewed. Also, specific issues are examined by a legal panel. The greatest advantages are potential problem patient exclusion, and enhanced physician-patient communication. Disadvantages include cost, user learning curve, and potential liability. Careful use of computer imaging should actually reduce one's liability when all aspects are considered. Recommendations for such use and specific legal issues are discussed.
Local field potentials and border ownership: A conjecture about computation in visual cortex.
Zucker, Steven W
2012-01-01
Border ownership is an intermediate-level visual task: it must integrate (upward flowing) image information about edges with (downward flowing) shape information. This highlights the familiar local-to-global aspect of border formation (linking of edge elements to form contours) with the much less studied global-to-local aspect (which edge elements form part of the same shape). To address this task we show how to incorporate certain high-level notions of distance and geometric arrangement into a form that can influence image-based edge information. The center of the argument is a reaction-diffusion equation that reveals how (global) aspects of the distance map (that is, shape) can be "read out" locally, suggesting a solution to the border ownership problem. Since the reaction-diffusion equation defines a field, a possible information processing role for the local field potential can be defined. We argue that such fields also underlie the Gestalt notion of closure, especially when it is refined using modern experimental techniques. An important implication of this theoretical argument is that, if true, then network modeling must be extended to include the substrate surrounding spiking neurons, including glia. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
De Luccia, Frank J.; Houchin, Scott; Porter, Brian C.; Graybill, Justin; Haas, Evan; Johnson, Patrick D.; Isaacson, Peter J.; Reth, Alan D.
2016-05-01
The GOES-R Flight Project has developed an Image Navigation and Registration (INR) Performance Assessment Tool Set (IPATS) for measuring Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM) INR performance metrics in the post-launch period for performance evaluation and long term monitoring. For ABI, these metrics are the 3-sigma errors in navigation (NAV), channel-to-channel registration (CCR), frame-to-frame registration (FFR), swath-to-swath registration (SSR), and within frame registration (WIFR) for the Level 1B image products. For GLM, the single metric of interest is the 3-sigma error in the navigation of background images (GLM NAV) used by the system to navigate lightning strikes. 3-sigma errors are estimates of the 99. 73rd percentile of the errors accumulated over a 24 hour data collection period. IPATS utilizes a modular algorithmic design to allow user selection of data processing sequences optimized for generation of each INR metric. This novel modular approach minimizes duplication of common processing elements, thereby maximizing code efficiency and speed. Fast processing is essential given the large number of sub-image registrations required to generate INR metrics for the many images produced over a 24 hour evaluation period. Another aspect of the IPATS design that vastly reduces execution time is the off-line propagation of Landsat based truth images to the fixed grid coordinates system for each of the three GOES-R satellite locations, operational East and West and initial checkout locations. This paper describes the algorithmic design and implementation of IPATS and provides preliminary test results.
NASA Technical Reports Server (NTRS)
DeLuccia, Frank J.; Houchin, Scott; Porter, Brian C.; Graybill, Justin; Haas, Evan; Johnson, Patrick D.; Isaacson, Peter J.; Reth, Alan D.
2016-01-01
The GOES-R Flight Project has developed an Image Navigation and Registration (INR) Performance Assessment Tool Set (IPATS) for measuring Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM) INR performance metrics in the post-launch period for performance evaluation and long term monitoring. For ABI, these metrics are the 3-sigma errors in navigation (NAV), channel-to-channel registration (CCR), frame-to-frame registration (FFR), swath-to-swath registration (SSR), and within frame registration (WIFR) for the Level 1B image products. For GLM, the single metric of interest is the 3-sigma error in the navigation of background images (GLM NAV) used by the system to navigate lightning strikes. 3-sigma errors are estimates of the 99.73rd percentile of the errors accumulated over a 24 hour data collection period. IPATS utilizes a modular algorithmic design to allow user selection of data processing sequences optimized for generation of each INR metric. This novel modular approach minimizes duplication of common processing elements, thereby maximizing code efficiency and speed. Fast processing is essential given the large number of sub-image registrations required to generate INR metrics for the many images produced over a 24 hour evaluation period. Another aspect of the IPATS design that vastly reduces execution time is the off-line propagation of Landsat based truth images to the fixed grid coordinates system for each of the three GOES-R satellite locations, operational East and West and initial checkout locations. This paper describes the algorithmic design and implementation of IPATS and provides preliminary test results.
NASA Technical Reports Server (NTRS)
De Luccia, Frank J.; Houchin, Scott; Porter, Brian C.; Graybill, Justin; Haas, Evan; Johnson, Patrick D.; Isaacson, Peter J.; Reth, Alan D.
2016-01-01
The GOES-R Flight Project has developed an Image Navigation and Registration (INR) Performance Assessment Tool Set (IPATS) for measuring Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM) INR performance metrics in the post-launch period for performance evaluation and long term monitoring. For ABI, these metrics are the 3-sigma errors in navigation (NAV), channel-to-channel registration (CCR), frame-to-frame registration (FFR), swath-to-swath registration (SSR), and within frame registration (WIFR) for the Level 1B image products. For GLM, the single metric of interest is the 3-sigma error in the navigation of background images (GLM NAV) used by the system to navigate lightning strikes. 3-sigma errors are estimates of the 99.73rd percentile of the errors accumulated over a 24-hour data collection period. IPATS utilizes a modular algorithmic design to allow user selection of data processing sequences optimized for generation of each INR metric. This novel modular approach minimizes duplication of common processing elements, thereby maximizing code efficiency and speed. Fast processing is essential given the large number of sub-image registrations required to generate INR metrics for the many images produced over a 24-hour evaluation period. Another aspect of the IPATS design that vastly reduces execution time is the off-line propagation of Landsat based truth images to the fixed grid coordinates system for each of the three GOES-R satellite locations, operational East and West and initial checkout locations. This paper describes the algorithmic design and implementation of IPATS and provides preliminary test results.
Color standardization and optimization in whole slide imaging.
Yagi, Yukako
2011-03-30
Standardization and validation of the color displayed by digital slides is an important aspect of digital pathology implementation. While the most common reason for color variation is the variance in the protocols and practices in the histology lab, the color displayed can also be affected by variation in capture parameters (for example, illumination and filters), image processing and display factors in the digital systems themselves. We have been developing techniques for color validation and optimization along two paths. The first was based on two standard slides that are scanned and displayed by the imaging system in question. In this approach, one slide is embedded with nine filters with colors selected especially for H&E stained slides (looking like tiny Macbeth color chart); the specific color of the nine filters were determined in our previous study and modified for whole slide imaging (WSI). The other slide is an H&E stained mouse embryo. Both of these slides were scanned and the displayed images were compared to a standard. The second approach was based on our previous multispectral imaging research. As a first step, the two slide method (above) was used to identify inaccurate display of color and its cause, and to understand the importance of accurate color in digital pathology. We have also improved the multispectral-based algorithm for more consistent results in stain standardization. In near future, the results of the two slide and multispectral techniques can be combined and will be widely available. We have been conducting a series of researches and developing projects to improve image quality to establish Image Quality Standardization. This paper discusses one of most important aspects of image quality - color.
Sharp-Tip Silver Nanowires Mounted on Cantilevers for High-Aspect-Ratio High-Resolution Imaging.
Ma, Xuezhi; Zhu, Yangzhi; Kim, Sanggon; Liu, Qiushi; Byrley, Peter; Wei, Yang; Zhang, Jin; Jiang, Kaili; Fan, Shoushan; Yan, Ruoxue; Liu, Ming
2016-11-09
Despite many efforts to fabricate high-aspect-ratio atomic force microscopy (HAR-AFM) probes for high-fidelity, high-resolution topographical imaging of three-dimensional (3D) nanostructured surfaces, current HAR probes still suffer from unsatisfactory performance, low wear-resistivity, and extravagant prices. The primary objective of this work is to demonstrate a novel design of a high-resolution (HR) HAR AFM probe, which is fabricated through a reliable, cost-efficient benchtop process to precisely implant a single ultrasharp metallic nanowire on a standard AFM cantilever probe. The force-displacement curve indicated that the HAR-HR probe is robust against buckling and bending up to 150 nN. The probes were tested on polymer trenches, showing a much better image fidelity when compared with standard silicon tips. The lateral resolution, when scanning a rough metal thin film and single-walled carbon nanotubes (SW-CNTs), was found to be better than 8 nm. Finally, stable imaging quality in tapping mode was demonstrated for at least 15 continuous scans indicating high resistance to wear. These results demonstrate a reliable benchtop fabrication technique toward metallic HAR-HR AFM probes with performance parallel or exceeding that of commercial HAR probes, yet at a fraction of their cost.
Referral criteria and clinical decision support: radiological protection aspects for justification.
Pérez, M del Rosario
2015-06-01
Advanced imaging technology has opened new horizons for medical diagnostics and improved patient care. However, many procedures are unjustified and do not provide a net benefit. An area of particular concern is the unnecessary use of radiation when clinical evaluation or other imaging modalities could provide an accurate diagnosis. Referral criteria for medical imaging are consensus statements based on the best-available evidence to assist the decision-making process when choosing the best imaging procedure for a given patient. Although they are advisory rather than compulsory, physicians should have good reasons for deviation from these criteria. Voluntary use of referral criteria has shown limited success compared with integration into clinical decision support systems. These systems support good medical practice, can improve health service delivery, and foster safer, more efficient, fair, cost-effective care, thus contributing to the strengthening of health systems. Justification of procedures and optimisation of protection, the two pillars of radiological protection in health care, are implicit in the notion of good medical practice. However, some health professionals are not familiar with these principles, and have low awareness of radiological protection aspects of justification. A stronger collaboration between radiation protection and healthcare communities could contribute to improve the radiation protection culture in medical practice. © The Chartered Institution of Building Services Engineers 2014.
Studies of the physical aspects of intumescence using advance diagnostics methods
NASA Astrophysics Data System (ADS)
Saeed, Hussain; Huang, Hua Wei; Zhang, Yang
2014-04-01
The use of intumescent paints as an active fire protection method has gained immense interest in recent years. A significant aspect of research has focused on studying the chemical aspects of the system to improve performance. The dynamics and physical aspects of intumescence in real time fire conditions are still unclear. The present research uses an experimental approach where diagnostics techniques such as thermal imaging camera was used to study intumescent characteristics that have been not been reported in great detail. T-panels are a substitute to the most commonly used part in construction, the I-beam. Studies were conducted using a cone calorimeter that provided a uniform heat flux through radiation on steel T-panel samples. The complex nature of char movement was recorded and a novel algorithm was used to track the growing char laye07r. The samples are designed to cater to different fire conditions. Therefore, the degree of intumescence was observed to be very different in the samples. The samples designed for low temperature cellulosic fires focus on high degree of intumesce. Whereas, mechanical strength is the focus for samples used in high temperature turbulent hydrocarbon fire conditions. The variation in the internal structure of the sample is presented. Furthermore, the phenomenon is phase shift is discussed. The phase shift is an essential part of the process of intumescence when the majority of intumescence occurs. It was observed to be different in all the samples. The movement of the samples is a property of great interest. This is because if any part of the substrate is exposed then the formulation does not meet strict commercialisation criterion. The movement was diagonal in nature as compared to flat panels where it is perpendicular. This is due tot the heating pattern of the plate that results in the web part of the panel to influence the growth of char on the flange part of the panel. A special case of char cracking is also highlighted and using image processing algorithm on the thermal imaging data. A quantitative method of analsysis is presented to an otherwise commonly qualitative nature of experimental study in this field.
Web-based document image processing
NASA Astrophysics Data System (ADS)
Walker, Frank L.; Thoma, George R.
1999-12-01
Increasing numbers of research libraries are turning to the Internet for electron interlibrary loan and for document delivery to patrons. This has been made possible through the widespread adoption of software such as Ariel and DocView. Ariel, a product of the Research Libraries Group, converts paper-based documents to monochrome bitmapped images, and delivers them over the Internet. The National Library of Medicine's DocView is primarily designed for library patrons are beginning to reap the benefits of this new technology, barriers exist, e.g., differences in image file format, that lead to difficulties in the use of library document information. To research how to overcome such barriers, the Communications Engineering Branch of the Lister Hill National Center for Biomedical Communications, an R and D division of NLM, has developed a web site called the DocMorph Server. This is part of an ongoing intramural R and D program in document imaging that has spanned many aspects of electronic document conversion and preservation, Internet document transmission and document usage. The DocMorph Server Web site is designed to fill two roles. First, in a role that will benefit both libraries and their patrons, it allows Internet users to upload scanned image files for conversion to alternative formats, thereby enabling wider delivery and easier usage of library document information. Second, the DocMorph Server provides the design team an active test bed for evaluating the effectiveness and utility of new document image processing algorithms and functions, so that they may be evaluated for possible inclusion in other image processing software products being developed at NLM or elsewhere. This paper describes the design of the prototype DocMorph Server and the image processing functions being implemented on it.
An improved architecture for video rate image transformations
NASA Technical Reports Server (NTRS)
Fisher, Timothy E.; Juday, Richard D.
1989-01-01
Geometric image transformations are of interest to pattern recognition algorithms for their use in simplifying some aspects of the pattern recognition process. Examples include reducing sensitivity to rotation, scale, and perspective of the object being recognized. The NASA Programmable Remapper can perform a wide variety of geometric transforms at full video rate. An architecture is proposed that extends its abilities and alleviates many of the first version's shortcomings. The need for the improvements are discussed in the context of the initial Programmable Remapper and the benefits and limitations it has delivered. The implementation and capabilities of the proposed architecture are discussed.
A spatio-temporal model of the human observer for use in display design
NASA Astrophysics Data System (ADS)
Bosman, Dick
1989-08-01
A "quick look" visual model, a kind of standard observer in software, is being developed to estimate the appearance of new display designs before prototypes are built. It operates on images also stored in software. It is assumed that the majority of display design flaws and technology artefacts can be identified in representations of early visual processing, and insight obtained into very local to global (supra-threshold) brightness distributions. Cognitive aspects are not considered because it seems that poor acceptance of technology and design is only weakly coupled to image content.
Exploring an optimal wavelet-based filter for cryo-ET imaging.
Huang, Xinrui; Li, Sha; Gao, Song
2018-02-07
Cryo-electron tomography (cryo-ET) is one of the most advanced technologies for the in situ visualization of molecular machines by producing three-dimensional (3D) biological structures. However, cryo-ET imaging has two serious disadvantages-low dose and low image contrast-which result in high-resolution information being obscured by noise and image quality being degraded, and this causes errors in biological interpretation. The purpose of this research is to explore an optimal wavelet denoising technique to reduce noise in cryo-ET images. We perform tests using simulation data and design a filter using the optimum selected wavelet parameters (three-level decomposition, level-1 zeroed out, subband-dependent threshold, a soft-thresholding and spline-based discrete dyadic wavelet transform (DDWT)), which we call a modified wavelet shrinkage filter; this filter is suitable for noisy cryo-ET data. When testing using real cryo-ET experiment data, higher quality images and more accurate measures of a biological structure can be obtained with the modified wavelet shrinkage filter processing compared with conventional processing. Because the proposed method provides an inherent advantage when dealing with cryo-ET images, it can therefore extend the current state-of-the-art technology in assisting all aspects of cryo-ET studies: visualization, reconstruction, structural analysis, and interpretation.
Technical aspects of cardiac PET/MRI.
Masuda, Atsuro; Nemoto, Ayaka; Takeishi, Yasuchika
2018-06-01
PET/MRI is a novel modality that enables to combine PET and MR images, and has significant potential to evaluate various cardiac diseases through the combination of PET molecular imaging and MRI functional imaging. Precise management of technical issues, however, is necessary for cardiac PET/MRI. This article describes several technical points, including patient preparation, MR attenuation correction, parallel acquisition of PET with MRI, clinical aspects, and image quality control.
Ansari, Daniel; Dhital, Bibek
2006-11-01
Numerical magnitude processing is an essential everyday skill. Functional brain imaging studies with human adults have repeatedly revealed that bilateral regions of the intraparietal sulcus are correlated with various numerical and mathematical skills. Surprisingly little, however, is known about the development of these brain representations. In the present study, we used functional neuroimaging to compare the neural correlates of nonsymbolic magnitude judgments between children and adults. Although behavioral performance was similar across groups, in comparison to the group of children the adult participants exhibited greater effects of numerical distance on the left intraparietal sulcus. Our findings are the first to reveal that even the most basic aspects of numerical cognition are subject to age-related changes in functional neuroanatomy. We propose that developmental impairments of number may be associated with atypical specialization of cortical regions underlying magnitude processing.
Image-algebraic design of multispectral target recognition algorithms
NASA Astrophysics Data System (ADS)
Schmalz, Mark S.; Ritter, Gerhard X.
1994-06-01
In this paper, we discuss methods for multispectral ATR (Automated Target Recognition) of small targets that are sensed under suboptimal conditions, such as haze, smoke, and low light levels. In particular, we discuss our ongoing development of algorithms and software that effect intelligent object recognition by selecting ATR filter parameters according to ambient conditions. Our algorithms are expressed in terms of IA (image algebra), a concise, rigorous notation that unifies linear and nonlinear mathematics in the image processing domain. IA has been implemented on a variety of parallel computers, with preprocessors available for the Ada and FORTRAN languages. An image algebra C++ class library has recently been made available. Thus, our algorithms are both feasible implementationally and portable to numerous machines. Analyses emphasize the aspects of image algebra that aid the design of multispectral vision algorithms, such as parameterized templates that facilitate the flexible specification of ATR filters.
Mining biomedical images towards valuable information retrieval in biomedical and life sciences.
Ahmed, Zeeshan; Zeeshan, Saman; Dandekar, Thomas
2016-01-01
Biomedical images are helpful sources for the scientists and practitioners in drawing significant hypotheses, exemplifying approaches and describing experimental results in published biomedical literature. In last decades, there has been an enormous increase in the amount of heterogeneous biomedical image production and publication, which results in a need for bioimaging platforms for feature extraction and analysis of text and content in biomedical images to take advantage in implementing effective information retrieval systems. In this review, we summarize technologies related to data mining of figures. We describe and compare the potential of different approaches in terms of their developmental aspects, used methodologies, produced results, achieved accuracies and limitations. Our comparative conclusions include current challenges for bioimaging software with selective image mining, embedded text extraction and processing of complex natural language queries. © The Author(s) 2016. Published by Oxford University Press.
2D dose distribution images of a hybrid low field MRI-γ detector
NASA Astrophysics Data System (ADS)
Abril, A.; Agulles-Pedrós, L.
2016-07-01
The proposed hybrid system is a combination of a low field MRI and dosimetric gel as a γ detector. The readout system is based on the polymerization process induced by the gel radiation. A gel dose map is obtained which represents the functional part of hybrid image alongside with the anatomical MRI one. Both images should be taken while the patient with a radiopharmaceutical is located inside the MRI system with a gel detector matrix. A relevant aspect of this proposal is that the dosimetric gel has never been used to acquire medical images. The results presented show the interaction of the 99mTc source with the dosimetric gel simulated in Geant4. The purpose was to obtain the planar γ 2D-image. The different source configurations are studied to explore the ability of the gel as radiation detector through the following parameters; resolution, shape definition and radio-pharmaceutical concentration.
Optical implementation of the synthetic discriminant function
NASA Astrophysics Data System (ADS)
Butler, S.; Riggins, J.
1984-10-01
Much attention is focused on the use of coherent optical pattern recognition (OPR) using matched spatial filters for robotics and intelligent systems. The OPR problem consists of three aspects -- information input, information processing, and information output. This paper discusses the information processing aspect which consists of choosing a filter to provide robust correlation with high efficiency. The filter should ideally be invariant to image shift, rotation and scale, provide a reasonable signal-to-noise (S/N) ratio and allow high throughput efficiency. The physical implementation of a spatial matched filter involves many choices. These include the use of conventional holograms or computer-generated holograms (CGH) and utilizing absorption or phase materials. Conventional holograms inherently modify the reference image by non-uniform emphasis of spatial frequencies. Proper use of film nonlinearity provides improved filter performance by emphasizing frequency ranges crucial to target discrimination. In the case of a CGH, the emphasis of the reference magnitude and phase can be controlled independently of the continuous tone or binary writing processes. This paper describes computer simulation and optical implementation of a geometrical shape and a Synthetic Discriminant Function (SDF) matched filter. The authors chose the binary Allebach-Keegan (AK) CGH algorithm to produce actual filters. The performances of these filters were measured to verify the simulation results. This paper provides a brief summary of the matched filter theory, the SDF, CGH algorithms, Phase-Only-Filtering, simulation procedures, and results.
Application of High Speed Digital Image Correlation in Rocket Engine Hot Fire Testing
NASA Technical Reports Server (NTRS)
Gradl, Paul R.; Schmidt, Tim
2016-01-01
Hot fire testing of rocket engine components and rocket engine systems is a critical aspect of the development process to understand performance, reliability and system interactions. Ground testing provides the opportunity for highly instrumented development testing to validate analytical model predictions and determine necessary design changes and process improvements. To properly obtain discrete measurements for model validation, instrumentation must survive in the highly dynamic and extreme temperature application of hot fire testing. Digital Image Correlation has been investigated and being evaluated as a technique to augment traditional instrumentation during component and engine testing providing further data for additional performance improvements and cost savings. The feasibility of digital image correlation techniques were demonstrated in subscale and full scale hotfire testing. This incorporated a pair of high speed cameras to measure three-dimensional, real-time displacements and strains installed and operated under the extreme environments present on the test stand. The development process, setup and calibrations, data collection, hotfire test data collection and post-test analysis and results are presented in this paper.
Sentence processing in the cerebral cortex.
Sakai, K L; Hashimoto, R; Homae, F
2001-01-01
Human language is a unique faculty of the mind. It has been the ultimate mystery throughout the history of neuroscience. Despite many aphasia and functional imaging studies, the exact correlation between cortical language areas and subcomponents of the linguistic system has not been established. One notable drawback is that most functional imaging studies have tested language tasks at the word level, such as lexical decision and word generation tasks, thereby neglecting the syntactic aspects of the language faculty. As proposed by Chomsky, the critical knowledge of language involves universal grammar (UG), which governs the syntactic structure of sentences. In this article, we will review recent advances made by functional neuroimaging studies of language, focusing especially on sentence processing in the cerebral cortex. We also present the recent results of our functional magnetic resonance imaging (fMRI) study intended to identify cortical areas specifically involved in syntactic processing. A study of sentence processing that employs a newly developed technique, optical topography (OT), is also presented. Based on these findings, we propose a modular specialization of Broca's area, Wernicke's area, and the angular gyrus/supramarginal gyrus. The current direction of research in neuroscience is beginning to establish the existence of distinct modules responsible for our knowledge of language.
Brain Mechanisms Supporting Discrimination of Sensory Features of Pain: A New Model
Oshiro, Yoshitetsu; Quevedo, Alexandre S.; McHaffie, John G.; Kraft, Robert A.; Coghill, Robert C.
2010-01-01
Pain can be very intense or only mild, and can be well localized or diffuse. To date, little is known as to how such distinct sensory aspects of noxious stimuli are processed by the human brain. Using functional magnetic resonance imaging and a delayed match-to-sample task, we show that discrimination of pain intensity, a non-spatial aspect of pain, activates a ventrally directed pathway extending bilaterally from the insular cortex to the prefrontal cortex. This activation is distinct from the dorsally-directed activation of the posterior parietal cortex and right dorsolateral prefrontal cortex that occurs during spatial discrimination of pain. Both intensity and spatial discrimination tasks activate highly similar aspects of the anterior cingulate cortex, suggesting that this structure contributes to common elements of the discrimination task such as the monitoring of sensory comparisons and response selection. Taken together, these results provide the foundation for a new model of pain in which bidirectional dorsal and ventral streams preferentially amplify and process distinct sensory features of noxious stimuli according to top-down task demands. PMID:19940188
Etching of Silicon in HBr Plasmas for High Aspect Ratio Features
NASA Technical Reports Server (NTRS)
Hwang, Helen H.; Meyyappan, M.; Mathad, G. S.; Ranade, R.
2002-01-01
Etching in semiconductor processing typically involves using halides because of the relatively fast rates. Bromine containing plasmas can generate high aspect ratio trenches, desirable for DRAM and MEMS applications, with relatively straight sidewalk We present scanning electron microscope images for silicon-etched trenches in a HBr plasma. Using a feature profile simulation, we show that the removal yield parameter, or number of neutrals removed per incident ion due to all processes (sputtering, spontaneous desorption, etc.), dictates the profile shape. We find that the profile becomes pinched off when the removal yield is a constant, with a maximum aspect ratio (AR) of about 5 to 1 (depth to height). When the removal yield decreases with increasing ion angle, the etch rate increases at the comers and the trench bottom broadens. The profiles have ARs of over 9:1 for yields that vary with ion angle. To match the experimentally observed etched time of 250 s for an AR of 9:1 with a trench width of 0.135 microns, we find that the neutral flux must be 3.336 x 10(exp 17)sq cm/s.
NASA Astrophysics Data System (ADS)
Tsuji, Hidenobu; Imaki, Masaharu; Kotake, Nobuki; Hirai, Akihito; Nakaji, Masaharu; Kameyama, Shumpei
2017-03-01
We demonstrate a range imaging pulsed laser sensor with two-dimensional scanning of a transmitted beam and a scanless receiver using a high-aspect avalanche photodiode (APD) array for the eye-safe wavelength. The system achieves a high frame rate and long-range imaging with a relatively simple sensor configuration. We developed a high-aspect APD array for the wavelength of 1.5 μm, a receiver integrated circuit, and a range and intensity detector. By combining these devices, we realized 160×120 pixels range imaging with a frame rate of 8 Hz at a distance of about 50 m.
Profile of science process skills of Preservice Biology Teacher in General Biology Course
NASA Astrophysics Data System (ADS)
Susanti, R.; Anwar, Y.; Ermayanti
2018-04-01
This study aims to obtain portrayal images of science process skills among preservice biology teacher. This research took place in Sriwijaya University and involved 41 participants. To collect the data, this study used multiple choice test comprising 40 items to measure the mastery of science process skills. The data were then analyzed in descriptive manner. The results showed that communication aspect outperfomed the other skills with that 81%; while the lowest one was identifying variables and predicting (59%). In addition, basic science process skills was 72%; whereas for integrated skills was a bit lower, 67%. In general, the capability of doing science process skills varies among preservice biology teachers.
Disconnected aging: cerebral white matter integrity and age-related differences in cognition.
Bennett, I J; Madden, D J
2014-09-12
Cognition arises as a result of coordinated processing among distributed brain regions and disruptions to communication within these neural networks can result in cognitive dysfunction. Cortical disconnection may thus contribute to the declines in some aspects of cognitive functioning observed in healthy aging. Diffusion tensor imaging (DTI) is ideally suited for the study of cortical disconnection as it provides indices of structural integrity within interconnected neural networks. The current review summarizes results of previous DTI aging research with the aim of identifying consistent patterns of age-related differences in white matter integrity, and of relationships between measures of white matter integrity and behavioral performance as a function of adult age. We outline a number of future directions that will broaden our current understanding of these brain-behavior relationships in aging. Specifically, future research should aim to (1) investigate multiple models of age-brain-behavior relationships; (2) determine the tract-specificity versus global effect of aging on white matter integrity; (3) assess the relative contribution of normal variation in white matter integrity versus white matter lesions to age-related differences in cognition; (4) improve the definition of specific aspects of cognitive functioning related to age-related differences in white matter integrity using information processing tasks; and (5) combine multiple imaging modalities (e.g., resting-state and task-related functional magnetic resonance imaging; fMRI) with DTI to clarify the role of cerebral white matter integrity in cognitive aging. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.
Disconnected Aging: Cerebral White Matter Integrity and Age-Related Differences in Cognition
Bennett, Ilana J.; Madden, David J.
2013-01-01
Cognition arises as a result of coordinated processing among distributed brain regions and disruptions to communication within these neural networks can result in cognitive dysfunction. Cortical disconnection may thus contribute to the declines in some aspects of cognitive functioning observed in healthy aging. Diffusion tensor imaging (DTI) is ideally suited for the study of cortical disconnection as it provides indices of structural integrity within interconnected neural networks. The current review summarizes results of previous DTI aging research with the aim of identifying consistent patterns of age-related differences in white matter integrity, and of relationships between measures of white matter integrity and behavioral performance as a function of adult age. We outline a number of future directions that will broaden our current understanding of these brain-behavior relationships in aging. Specifically, future research should aim to (1) investigate multiple models of age-brain-behavior relationships; (2) determine the tract-specificity versus global effect of aging on white matter integrity; (3) assess the relative contribution of normal variation in white matter integrity versus white matter lesions to age-related differences in cognition; (4) improve the definition of specific aspects of cognitive functioning related to age-related differences in white matter integrity using information processing tasks; and (5) combine multiple imaging modalities (e.g., resting-state and task-related functional magnetic resonance imaging; fMRI) with DTI to clarify the role of cerebral white matter integrity in cognitive aging. PMID:24280637
TRMM Microwave Imager (TMI) Updates for Final Data Version Release
NASA Technical Reports Server (NTRS)
Kroodsma, Rachael A; Bilanow, Stephen; Ji, Yimin; McKague, Darren
2017-01-01
The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) dataset released by the Precipitation Processing System (PPS) will be updated to a final version within the next year. These updates are based on increased knowledge in recent years of radiometer calibration and sensor performance issues. In particular, the Global Precipitation Measurement (GPM) Microwave Imager (GMI) is used as a model for many of the TMI version updates. This paper discusses four aspects of the TMI data product that will be improved: spacecraft attitude, calibration and quality control, along-scan bias corrections, and sensor pointing accuracy. These updates will be incorporated into the final TMI data version, improving the quality of the data product and ensuring accurate geophysical parameters can be derived from TMI.
The continual innovation of commercial PET/CT solutions in nuclear cardiology: Siemens Healthineers.
Bendriem, Bernard; Reed, Jessie; McCullough, Kathryn; Khan, Mohammad Raza; Smith, Anne M; Thomas, Damita; Long, Misty
2018-04-10
Cardiac PET/CT is an evolving, non-invasive imaging modality that impacts patient management in many clinical scenarios. Beyond offering the capability to assess myocardial perfusion, inflammatory cardiac pathologies, and myocardial viability, cardiac PET/CT also allows for the non-invasive quantitative assessment of myocardial blood flow (MBF) and myocardial flow reserve (MFR). Recognizing the need for an enhanced comprehension of coronary physiology, Siemens Healthineers implemented a sophisticated solution for the calculation of MBF and MFR in 2009. As a result, each aspect of their innovative scanner and image-processing technology seamlessly integrates into an efficient, easy-to-use workflow for everyday clinical use that maximizes the number of patients who potentially benefit from this imaging modality.
Unified modeling language and design of a case-based retrieval system in medical imaging.
LeBozec, C.; Jaulent, M. C.; Zapletal, E.; Degoulet, P.
1998-01-01
One goal of artificial intelligence research into case-based reasoning (CBR) systems is to develop approaches for designing useful and practical interactive case-based environments. Explaining each step of the design of the case-base and of the retrieval process is critical for the application of case-based systems to the real world. We describe herein our approach to the design of IDEM--Images and Diagnosis from Examples in Medicine--a medical image case-based retrieval system for pathologists. Our approach is based on the expressiveness of an object-oriented modeling language standard: the Unified Modeling Language (UML). We created a set of diagrams in UML notation illustrating the steps of the CBR methodology we used. The key aspect of this approach was selecting the relevant objects of the system according to user requirements and making visualization of cases and of the components of the case retrieval process. Further evaluation of the expressiveness of the design document is required but UML seems to be a promising formalism, improving the communication between the developers and users. Images Figure 6 Figure 7 PMID:9929346
NASA Technical Reports Server (NTRS)
Lee, S. (Editor)
1985-01-01
A workshop was organized to stimulate and coordinate research on the properties of Martian dust, its distribution on the planet, and the processes affecting its yearly deposition, erosion, and transport. A great deal of research was carried out to understand local, regional, and global aspects of the Martian dust transport cycle, with the goal being definition of the currently active processes and their relation to those operating over the long term. To date, however, most individual research projects have centered around interpretation of single data sets (visual images, IRTM, radar, etc.), and these many efforts were not coordinated. Many of the details of short and long term dust-related processes, as inferred from the various single data sets, are still not agreed upon. It was the intent of this workshop to encourage the informal exchange of ideas among several researchers currently investigating various aspects of the problem and to investigate cooperative efforts to synthesize the individual approaches into a unified understanding of the present seasonal and yearly Martian sediment transport cycles.
Usefulness of tissue autofluorescence imaging in actinic cheilitis diagnosis.
Takahama Junior, Ademar; Kurachi, Cristina; Cosci, Alessandro; Pereira Faustino, Isabel Schausltz; Camisasca, Danielle Resende; da Costa Fontes, Karla Bianca Fernandes; Pires, Fábio Ramôa; Azevedo, Rebeca Souza
2013-07-01
Actinic cheilitis (AC) is a potentially malignant disorder of the lips. Because of its heterogeneous clinical aspect, it is difficult to indicate representative biopsy area. The purpose of this study was to evaluate the usefulness of tissue autofluorescence in AC diagnosis. The system was composed of a 405-nm light-emitting diode, sent to the sample by a dichroic, that allows the fluorescence signal to reach a camera directly plugged in the system. Fifty-seven patients with clinical diagnosis of AC and 45 normal volunteers were selected. According to clinical and fluorescence features, one or more areas were selected for biopsies in the AC group and epithelial dysplasia (ED) grades were established. The autofluorescence images were processed by a clustering algorithm for AC automated diagnosis. The tissue autofluorescence image revealed a heterogeneous pattern of loss and increase of fluorescence in patients with AC. ED was found in 93% of the cases, and most of the areas graded as moderate or severe ED were chosen with the aid of autofluorescence. The processed autofluorescence images from AC patients showed a higher number of spots in an irregular pattern. Tissue autofluorescence image system is a useful technique in association with clinical examination for AC diagnosis.
NASA Astrophysics Data System (ADS)
Lawi, Armin; Adhitya, Yudhi
2018-03-01
The objective of this research is to determine the quality of cocoa beans through morphology of their digital images. Samples of cocoa beans were scattered on a bright white paper under a controlled lighting condition. A compact digital camera was used to capture the images. The images were then processed to extract their morphological parameters. Classification process begins with an analysis of cocoa beans image based on morphological feature extraction. Parameters for extraction of morphological or physical feature parameters, i.e., Area, Perimeter, Major Axis Length, Minor Axis Length, Aspect Ratio, Circularity, Roundness, Ferret Diameter. The cocoa beans are classified into 4 groups, i.e.: Normal Beans, Broken Beans, Fractured Beans, and Skin Damaged Beans. The model of classification used in this paper is the Multiclass Ensemble Least-Squares Support Vector Machine (MELS-SVM), a proposed improvement model of SVM using ensemble method in which the separate hyperplanes are obtained by least square approach and the multiclass procedure uses One-Against- All method. The result of our proposed model showed that the classification with morphological feature input parameters were accurately as 99.705% for the four classes, respectively.
The nature of face representations in subcortical regions.
Gabay, Shai; Burlingham, Charles; Behrmann, Marlene
2014-07-01
Studies examining the neural correlates of face perception in humans have focused almost exclusively on the distributed cortical network of face-selective regions. Recently, however, investigations have also identified subcortical correlates of face perception and the question addressed here concerns the nature of these subcortical face representations. To explore this issue, we presented to participants pairs of images sequentially to the same or to different eyes. Superior performance in the former over latter condition implicates monocular, prestriate portions of the visual system. Over a series of five experiments, we manipulated both lower-level (size, location) as well as higher-level (identity) similarity across the pair of faces. A monocular advantage was observed even when the faces in a pair differed in location and in size, implicating some subcortical invariance across lower-level image properties. A monocular advantage was also observed when the faces in a pair were two different images of the same individual, indicating the engagement of subcortical representations in more abstract, higher-level aspects of face processing. We conclude that subcortical structures of the visual system are involved, perhaps interactively, in multiple aspects of face perception, and not simply in deriving initial coarse representations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Empowering schoolchildren to do astronomical science with images
NASA Astrophysics Data System (ADS)
Raeside, L.; Busschots, B.; O'Cinneide, E.; Foy, S.; Keating, J. G.
2005-06-01
In 1991 the TIE (Telescopes in Education) Foundation provided schoolchildren with the ability to access professional observatory telescopes remotely. TIE has raised the profile of astronomy and science among schoolchildren. Since the initiation of this facility the TIE Foundation have spread their reach from one telescope in the US to many telescopes and many schools across the globe. The VTIE (Virtual Telescopes in Education) project was launched in 2001 to build on the success of TIE. The VTIE VLE (Virtual Learning Environment) provides a Web portal through which pupils can create a scientific proposal, retrieve astronomical images, and produce a scientific paper summarizing their learning experiences of the VTIE scientific process. Since the completion of the first formative evaluations of VTIE (which involved over 250 schoolchildren) it has been observed that the participating schoolchildren have had difficulty completing and understanding the practical imaging aspects of astronomical science. Our experimental observations have revealed that the imaging tools currently available to astronomers have not ported well to schools. The VTIE imaging tools developed during our research will provide schoolchildren with the ability to store, acquire, manipulate and analyze images within the VTIE VLE. It is hypothesized herein that the provision of exclusively child-centered imaging software components will improve greatly the children's empowerment within the VTIE scientific process. Consequentially the addition of fully integrated child-centered imaging tools will contribute positively to the overall VTIE goal to promote science among schoolchildren.
Seismic tomography; theory and practice
Iver, H.M.; Hirahara, Kazuro
1993-01-01
Although highly theoretical and computer-orientated, seismic tomography has created spectacular images of anomolies within the Earth with dimensions of thousands of kilometers to few tens of meters. These images have enabled Earth scientists working on diverse areas to attack fundamental problems relating to the deep dynamical processes within our planet. Additionally, this technique is being used extensively to study the Earth's hazardous regions such as earthquake fault zones and volcanoes, as well as features beneficial to man such as oil or mineral-bearing structures. This book has been written by world experts and describes the theories, experimental and analytical procedures and results of applying seismic tomography from global to purely local scale. It represents the collective global perspective on the state of the art and focusses not only on the theoretical and practical aspects, but also on the uses for hydrocarbon, mineral and geothermal exploitation. Students and researchers in the Earth sciences, and research and exploration geophysicists should find this a useful, practical reference book for all aspects of their work.
Conceptual design of an on-board optical processor with components
NASA Technical Reports Server (NTRS)
Walsh, J. R.; Shackelford, R. G.
1977-01-01
The specification of components for a spacecraft on-board optical processor was investigated. A space oriented application of optical data processing and the investigation of certain aspects of optical correlators were examined. The investigation confirmed that real-time optical processing has made significant advances over the past few years, but that there are still critical components which will require further development for use in an on-board optical processor. The devices evaluated were the coherent light valve, the readout optical modulator, the liquid crystal modulator, and the image forming light modulator.
Sedgewick, Gerald J.; Ericson, Marna
2015-01-01
Obtaining digital images of color brightfield microscopy is an important aspect of biomedical research and the clinical practice of diagnostic pathology. Although the field of digital pathology has had tremendous advances in whole-slide imaging systems, little effort has been directed toward standardizing color brightfield digital imaging to maintain image-to-image consistency and tonal linearity. Using a single camera and microscope to obtain digital images of three stains, we show that microscope and camera systems inherently produce image-to-image variation. Moreover, we demonstrate that post-processing with a widely used raster graphics editor software program does not completely correct for session-to-session inconsistency. We introduce a reliable method for creating consistent images with a hardware/software solution (ChromaCal™; Datacolor Inc., NJ) along with its features for creating color standardization, preserving linear tonal levels, providing automated white balancing and setting automated brightness to consistent levels. The resulting image consistency using this method will also streamline mean density and morphometry measurements, as images are easily segmented and single thresholds can be used. We suggest that this is a superior method for color brightfield imaging, which can be used for quantification and can be readily incorporated into workflows. PMID:25575568
Real-time simulation of the retina allowing visualization of each processing stage
NASA Astrophysics Data System (ADS)
Teeters, Jeffrey L.; Werblin, Frank S.
1991-08-01
The retina computes to let us see, but can we see the retina compute? Until now, the answer has been no, because the unconscious nature of the processing hides it from our view. Here the authors describe a method of seeing computations performed throughout the retina. This is achieved by using neurophysiological data to construct a model of the retina, and using a special-purpose image processing computer (PIPE) to implement the model in real time. Processing in the model is organized into stages corresponding to computations performed by each retinal cell type. The final stage is the transient (change detecting) ganglion cell. A CCD camera forms the input image, and the activity of a selected retinal cell type is the output which is displayed on a TV monitor. By changing the retina cell driving the monitor, the progressive transformations of the image by the retina can be observed. These simulations demonstrate the ubiquitous presence of temporal and spatial variations in the patterns of activity generated by the retina which are fed into the brain. The dynamical aspects make these patterns very different from those generated by the common DOG (Difference of Gaussian) model of receptive field. Because the retina is so successful in biological vision systems, the processing described here may be useful in machine vision.
On-line range images registration with GPGPU
NASA Astrophysics Data System (ADS)
Będkowski, J.; Naruniec, J.
2013-03-01
This paper concerns implementation of algorithms in the two important aspects of modern 3D data processing: data registration and segmentation. Solution proposed for the first topic is based on the 3D space decomposition, while the latter on image processing and local neighbourhood search. Data processing is implemented by using NVIDIA compute unified device architecture (NIVIDIA CUDA) parallel computation. The result of the segmentation is a coloured map where different colours correspond to different objects, such as walls, floor and stairs. The research is related to the problem of collecting 3D data with a RGB-D camera mounted on a rotated head, to be used in mobile robot applications. Performance of the data registration algorithm is aimed for on-line processing. The iterative closest point (ICP) approach is chosen as a registration method. Computations are based on the parallel fast nearest neighbour search. This procedure decomposes 3D space into cubic buckets and, therefore, the time of the matching is deterministic. First technique of the data segmentation uses accele-rometers integrated with a RGB-D sensor to obtain rotation compensation and image processing method for defining pre-requisites of the known categories. The second technique uses the adapted nearest neighbour search procedure for obtaining normal vectors for each range point.
Wildgruber, D; Hertrich, I; Riecker, A; Erb, M; Anders, S; Grodd, W; Ackermann, H
2004-12-01
In addition to the propositional content of verbal utterances, significant linguistic and emotional information is conveyed by the tone of speech. To differentiate brain regions subserving processing of linguistic and affective aspects of intonation, discrimination of sentences differing in linguistic accentuation and emotional expressiveness was evaluated by functional magnetic resonance imaging. Both tasks yielded rightward lateralization of hemodynamic responses at the level of the dorsolateral frontal cortex as well as bilateral thalamic and temporal activation. Processing of linguistic and affective intonation, thus, seems to be supported by overlapping neural networks comprising partially right-sided brain regions. Comparison of hemodynamic activation during the two different tasks, however, revealed bilateral orbito-frontal responses restricted to the affective condition as opposed to activation of the left lateral inferior frontal gyrus confined to evaluation of linguistic intonation. These findings indicate that distinct frontal regions contribute to higher level processing of intonational information depending on its communicational function. In line with other components of language processing, discrimination of linguistic accentuation seems to be lateralized to the left inferior-lateral frontal region whereas bilateral orbito-frontal areas subserve evaluation of emotional expressiveness.
A Solar Aspect System for the HEROES Mission
NASA Technical Reports Server (NTRS)
Christe, Steven; Shih, Albert; Rodriguez, Marcello; Gregory, Kyle; Cramer, Alexander; Edgerton, Melissa; Gaskin, Jessica; O'Connor, Brian; Sobey, Alexander
2014-01-01
A new Solar Aspect System (SAS) has been developed to provide the ability to observe the Sun on an existing balloon payload HERO (short for High Energy Replicated Optics). Developed under the HEROES program (High Energy Replicated Optics to Explore the Sun), the SAS aspect system provides solar pointing knowledge in pitch, yaw, and roll. The required precision of these measurements must be better than the HEROES X-ray resolution of approximately 20 arcsec Full Width at Half Maximum (FWHM) so as to not degrade the image resolution. The SAS consists of two separate systems: the Pitch-Yaw Aspect System (PYAS) and the Roll Aspect System (RAS). The PYAS functions by projecting an image of the Sun onto a screen with precision fiducials. A CCD camera takes an image of these fiducials, and an automated algorithm determines the location of the Sun as well as the location of the fiducials. The spacing between fiducials is unique and allows each to be identified so that the location of the Sun on the screen can be precisely determined. The RAS functions by imaging the Earth's horizon in opposite directions using a silvered prism imaged by a CCD camera. The design and first results of the performance of these systems during the HEROES flight which occurred in September 2013 are presented here.
Single-molecule live-cell imaging of bacterial DNA repair and damage tolerance.
Ghodke, Harshad; Ho, Han; van Oijen, Antoine M
2018-02-19
Genomic DNA is constantly under threat from intracellular and environmental factors that damage its chemical structure. Uncorrected DNA damage may impede cellular propagation or even result in cell death, making it critical to restore genomic integrity. Decades of research have revealed a wide range of mechanisms through which repair factors recognize damage and co-ordinate repair processes. In recent years, single-molecule live-cell imaging methods have further enriched our understanding of how repair factors operate in the crowded intracellular environment. The ability to follow individual biochemical events, as they occur in live cells, makes single-molecule techniques tremendously powerful to uncover the spatial organization and temporal regulation of repair factors during DNA-repair reactions. In this review, we will cover practical aspects of single-molecule live-cell imaging and highlight recent advances accomplished by the application of these experimental approaches to the study of DNA-repair processes in prokaryotes. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
Applications of LC-MS in PET Radioligand Development and Metabolic Elucidation
Ma, Ying; Kiesewetter, Dale O.; Lang, Lixin; Gu, Dongyu; Chen, Xiaoyuan
2013-01-01
Positron emission tomography (PET) is a very sensitive molecular imaging technique that when employed with an appropriate radioligand has the ability to quantititate physiological processes in a non-invasive manner. Since the imaging technique detects all radioactive emissions in the field of view, the presence and biological activity of radiolabeled metabolites must be determined for each radioligand in order to validate the utility of the radiotracer for measuring the desired physiological process. Thus, the identification of metabolic profiles of radiolabeled compounds is an important aspect of design, development, and validation of new radiopharmaceuticals and their applications in drug development and molecular imaging. Metabolite identification for different chemical classes of radiopharmaceuticals allows rational design to minimize the formation and accumulation of metabolites in the target tissue, either through enhanced excretion or minimized metabolism. This review will discuss methods for identifying and quantitating metabolites during the pre-clinical development of radiopharmaceuticals with special emphasis on the application of LC/MS. PMID:20540692
NASA Astrophysics Data System (ADS)
Luo, T.; Chen, J. X.; Zhuo, S. M.; Lu, K. C.; Jiang, X. S.; Liu, Q. G.
2009-03-01
The purpose of this study is to highlight a clearer understanding of the process of collagen regeneration during wound healing. By means of second harmonic generation (SHG) microscopy, the changes of collagen arrangement at the wound margin were analyzed at 0, 3, 5, 7, 11 and 13 days post injury. The degree of collagen disorders associated with the healing process was quantitatively obtained using the aspect ratio of polar plot image of collagen azimuthal angles and the healing status of collagen could be estimated by arithmetical mean deviation ( Ra) of the collagen SHG images. Our results suggest that SHG microscopy has potential advances in the collagen studies during wound healing and the arrangement of collagen fibers gradually transformed from disorder to order so as to contract the wound. It is capable of promoting clinical application of the noninvasive imaging tool and the analysis methods of collagen disorder as an effective scar management for prevention and treatment about aberrant healing.
Image Processing Occupancy Sensor
DOE Office of Scientific and Technical Information (OSTI.GOV)
The Image Processing Occupancy Sensor, or IPOS, is a novel sensor technology developed at the National Renewable Energy Laboratory (NREL). The sensor is based on low-cost embedded microprocessors widely used by the smartphone industry and leverages mature open-source computer vision software libraries. Compared to traditional passive infrared and ultrasonic-based motion sensors currently used for occupancy detection, IPOS has shown the potential for improved accuracy and a richer set of feedback signals for occupant-optimized lighting, daylighting, temperature setback, ventilation control, and other occupancy and location-based uses. Unlike traditional passive infrared (PIR) or ultrasonic occupancy sensors, which infer occupancy based only onmore » motion, IPOS uses digital image-based analysis to detect and classify various aspects of occupancy, including the presence of occupants regardless of motion, their number, location, and activity levels of occupants, as well as the illuminance properties of the monitored space. The IPOS software leverages the recent availability of low-cost embedded computing platforms, computer vision software libraries, and camera elements.« less
PACS in an intensive care unit: results from a randomized controlled trial
NASA Astrophysics Data System (ADS)
Bryan, Stirling; Weatherburn, Gwyneth C.; Watkins, Jessamy; Walker, Samantha; Wright, Carl; Waters, Brian; Evans, Jeff; Buxton, Martin J.
1998-07-01
The objective of this research was to assess the costs and benefits associated with the introduction of a small PACS system into an intensive care unit (ICU) at a district general hospital in north Wales. The research design adopted for this study was a single center randomized controlled trial (RCT). Patients were randomly allocated either to a trial arm where their x-ray imaging was solely film-based or to a trial arm where their x-ray imaging was solely PACS based. Benefit measures included examination-based process measures, such as image turn-round time, radiation dose and image unavailability; and patient-related process measures, which included adverse events and length of stay. The measurement of costs focused on additional 'radiological' costs and the costs of patient management. The study recruited 600 patients. The key findings from this study were that the installation of PACS was associated with important benefits in terms of image availability, and important costs in both monetary and radiation dose terms. PACS-related improvements in terms of more timely 'clinical actions' were not found. However, the qualitative aspect of the research found that clinicians were advocates of the technology and believed that an important benefit of PACS related to improved image availability.
Blanc-Garin, J; Faure, S; Sabio, P
1993-05-01
The objective of this study was to analyze dynamic aspects of right hemisphere implementation in processing visual images. Two tachistoscopic, divided visual field experiments were carried out on a partial split-brain patient with no damage to the right hemisphere. In the first experiment, image generation performance for letters presented in the right visual field (/left hemisphere) was undeniably optimal. In the left visual field (/right hemisphere), performance was no better than chance level at first, but then improved dramatically across stimulation blocks, in each of five successive sessions. This was interpreted as revealing the progressive spontaneous activation of the right hemisphere's competence not shown initially. The aim of the second experiment was to determine some conditions under which this pattern was obtained. The experimental design contrasted stimuli (words and pictures) and representational activity (phonologic and visuo-imaged processing). The right visual field (/left hemisphere: LH) elicited higher performance than the left visual field (/right hemisphere, RH) in the three situations where verbal activity was required. No superiority could be found when visual images were to be generated from pictures: parallel and weak improvement of both hemispheres was observed across sessions. Two other patterns were obtained: improvement in RH performance (although LH performance remained superior) and an unexpectedly large decrease in RH performance. These data are discussed in terms of RH cognitive competence and hemisphere implementation.
Hock, Sabrina; Hasenauer, Jan; Theis, Fabian J
2013-01-01
Diffusion is a key component of many biological processes such as chemotaxis, developmental differentiation and tissue morphogenesis. Since recently, the spatial gradients caused by diffusion can be assessed in-vitro and in-vivo using microscopy based imaging techniques. The resulting time-series of two dimensional, high-resolutions images in combination with mechanistic models enable the quantitative analysis of the underlying mechanisms. However, such a model-based analysis is still challenging due to measurement noise and sparse observations, which result in uncertainties of the model parameters. We introduce a likelihood function for image-based measurements with log-normal distributed noise. Based upon this likelihood function we formulate the maximum likelihood estimation problem, which is solved using PDE-constrained optimization methods. To assess the uncertainty and practical identifiability of the parameters we introduce profile likelihoods for diffusion processes. As proof of concept, we model certain aspects of the guidance of dendritic cells towards lymphatic vessels, an example for haptotaxis. Using a realistic set of artificial measurement data, we estimate the five kinetic parameters of this model and compute profile likelihoods. Our novel approach for the estimation of model parameters from image data as well as the proposed identifiability analysis approach is widely applicable to diffusion processes. The profile likelihood based method provides more rigorous uncertainty bounds in contrast to local approximation methods.
Imaging of cerebrovascular pathology in animal models of Alzheimer's disease
Klohs, Jan; Rudin, Markus; Shimshek, Derya R.; Beckmann, Nicolau
2014-01-01
In Alzheimer's disease (AD), vascular pathology may interact with neurodegeneration and thus aggravate cognitive decline. As the relationship between these two processes is poorly understood, research has been increasingly focused on understanding the link between cerebrovascular alterations and AD. This has at last been spurred by the engineering of transgenic animals, which display pathological features of AD and develop cerebral amyloid angiopathy to various degrees. Transgenic models are versatile for investigating the role of amyloid deposition and vascular dysfunction, and for evaluating novel therapeutic concepts. In addition, research has benefited from the development of novel imaging techniques, which are capable of characterizing vascular pathology in vivo. They provide vascular structural read-outs and have the ability to assess the functional consequences of vascular dysfunction as well as to visualize and monitor the molecular processes underlying these pathological alterations. This article focusses on recent in vivo small animal imaging studies addressing vascular aspects related to AD. With the technical advances of imaging modalities such as magnetic resonance, nuclear and microscopic imaging, molecular, functional and structural information related to vascular pathology can now be visualized in vivo in small rodents. Imaging vascular and parenchymal amyloid-β (Aβ) deposition as well as Aβ transport pathways have been shown to be useful to characterize their dynamics and to elucidate their role in the development of cerebral amyloid angiopathy and AD. Structural and functional imaging read-outs have been employed to describe the deleterious affects of Aβ on vessel morphology, hemodynamics and vascular integrity. More recent imaging studies have also addressed how inflammatory processes partake in the pathogenesis of the disease. Moreover, imaging can be pivotal in the search for novel therapies targeting the vasculature. PMID:24659966
A simple method for imaging axonal transport in aging neurons using the adult Drosophila wing.
Vagnoni, Alessio; Bullock, Simon L
2016-09-01
There is growing interest in the link between axonal cargo transport and age-associated neuronal dysfunction. The study of axonal transport in neurons of adult animals requires intravital or ex vivo imaging approaches, which are laborious and expensive in vertebrate models. We describe simple, noninvasive procedures for imaging cargo motility within axons using sensory neurons of the translucent Drosophila wing. A key aspect is a method for mounting the intact fly that allows detailed imaging of transport in wing neurons. Coupled with existing genetic tools in Drosophila, this is a tractable system for studying axonal transport over the life span of an animal and thus for characterization of the relationship between cargo dynamics, neuronal aging and disease. Preparation of a sample for imaging takes ∼5 min, with transport typically filmed for 2-3 min per wing. We also document procedures for the quantification of transport parameters from the acquired images and describe how the protocol can be adapted to study other cell biological processes in aging neurons.
JADA: a graphical user interface for comprehensive internal dose assessment in nuclear medicine.
Grimes, Joshua; Uribe, Carlos; Celler, Anna
2013-07-01
The main objective of this work was to design a comprehensive dosimetry package that would keep all aspects of internal dose calculation within the framework of a single software environment and that would be applicable for a variety of dose calculation approaches. Our MATLAB-based graphical user interface (GUI) can be used for processing data obtained using pure planar, pure SPECT, or hybrid planar/SPECT imaging. Time-activity data for source regions are obtained using a set of tools that allow the user to reconstruct SPECT images, load images, coregister a series of planar images, and to perform two-dimensional and three-dimensional image segmentation. Curve fits are applied to the acquired time-activity data to construct time-activity curves, which are then integrated to obtain time-integrated activity coefficients. Subsequently, dose estimates are made using one of three methods. The organ level dose calculation subGUI calculates mean organ doses that are equivalent to dose assessment performed by OLINDA/EXM. Voxelized dose calculation options, which include the voxel S value approach and Monte Carlo simulation using the EGSnrc user code DOSXYZnrc, are available within the process 3D image data subGUI. The developed internal dosimetry software package provides an assortment of tools for every step in the dose calculation process, eliminating the need for manual data transfer between programs. This saves times and minimizes user errors, while offering a versatility that can be used to efficiently perform patient-specific internal dose calculations in a variety of clinical situations.
NASA Technical Reports Server (NTRS)
Mcnider, Richard T.; Song, Aaron; Casey, Dan; Crosson, William; Wetzel, Peter
1993-01-01
The current NWS ground based network is not sufficient to capture the dynamic or thermodynamic structure leading to the initiation and organization of air mass moist convective events. Under this investigation we intend to use boundary layer mesoscale models (McNider and Pielke, 1981) to examine the dynamic triggering of convection due to topography and surface thermal contrasts. VAS and MAN's estimates of moisture will be coupled with the dynamic solution to provide an estimate of the total convective potential. Visible GOES images will be used to specify incoming insolation which may lead to surface thermal contrasts and JR skin temperatures will be used to estimate surface moisture (via the surface thermal inertia) (Weizel and Chang, 1988) which can also induce surface thermal contrasts. We will use the SPACE-COHMEX data base to evaluate the ability of the joint mesoscale model satellite products to show skill in predicting the development of air mass convection. We will develop images of model vertical velocity and satellite thermodynamic measures to derive images of predicted convective potential. We will then after suitable geographic registration carry out a pixel by pixel correlation between the model/satellite convective potential and the 'truth' which are the visible images. During the first half of the first year of this investigation we have concentrated on two aspects of the project. The first has been in generating vertical velocity fields from the model for COHMEX case days. We have taken June 19 as the first case and have run the mesoscale model at several different grid resolutions. We are currently developing the composite model/satellite convective image. The second aspect has been the attempted calibration of the surface energy budget to provide the proper horizontal thermal contrasts for convective initiation. We have made extensive progress on this aspect using the FIFE data as a test data set. The calibration technique looks very promising.
Use of multidimensional, multimodal imaging and PACS to support neurological diagnoses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, S.T.C.; Knowlton, R.; Hoo, K.S.
1995-12-31
Technological advances in brain imaging have revolutionized diagnosis in neurology and neurological surgery. Major imaging techniques include magnetic resonance imaging (MRI) to visualize structural anatomy, positron emission tomography (PET) to image metabolic function and cerebral blood flow, magnetoencephalography (MEG) to visualize the location of physiologic current sources, and magnetic resonance spectroscopy (MRS) to measure specific biochemicals. Each of these techniques studies different biomedical aspects of the grain, but there lacks an effective means to quantify and correlate the disparate imaging datasets in order to improve clinical decision making processes. This paper describes several techniques developed in a UNIX-based neurodiagnostic workstationmore » to aid the non-invasive presurgical evaluation of epilepsy patients. These techniques include on-line access to the picture archiving and communication systems (PACS) multimedia archive, coregistration of multimodality image datasets, and correlation and quantitative of structural and functional information contained in the registered images. For illustration, the authors describe the use of these techniques in a patient case of non-lesional neocortical epilepsy. They also present the future work based on preliminary studies.« less
NASA Astrophysics Data System (ADS)
Bernard, J.
2012-12-01
The Manufacturers of geophysical instruments have been facing these past decades the fast evolution of the electronics and of the computer sciences. More automatisms have been introduced into the equipment and into the processing and interpretation software which may let believe that conducting geophysical surveys requires less understanding of the method and less experience than in the past. Hence some misunderstandings in the skills that are needed to make the geophysical results well integrated among the global information which the applied geologist needs to acquire to be successful in his applications. Globally, the demand in geophysical investigation goes towards more penetration depth, requiring more powerful transmitters, and towards a better resolution, requiring more data such as in 3D analysis. Budgets aspects strongly suggest a high efficiency in the field associated to high speed data processing. The innovation is required in all aspects of geophysics to fit with the market needs, including new technological (instruments, software) and methodological (methods, procedures, arrays) developments. The structures in charge of the geophysical work can be public organisations (institutes, ministries, geological surveys,…) or can come from the private sector (large companies, sub-contractors, consultants, …), each one of them getting their own constraints in the field work and in the processing and interpretation phases. In the applications concerning Groundwater investigations, Mining Exploration, Environmental and Engineering surveys, examples of data and their interpretation presently carried out all around the world will be presented for DC Resistivity (Vertical Electrical Sounding, 2D, 3D Resistivity Imaging, Resistivity Monitoring), Induced Polarisation (Time Domain 2D, 3D arrays for mining and environmental), Magnetic Resonance Sounding (direct detection and characterisation of groundwater) and Electromagnetic (multi-component and multi-spacing Frequency Domain Sounding and Profiling technique). The place that Geophysics takes in the market among the other investigation techniques is, and will remain, dependant on the quality of the results obtained, despite the uncertainties linked to the field (noise aspects) and to the interpretation (equivalence aspects), under the control of budget decisions.Resistivity Imaging measurements for groundwater investigations
Conghe Song; Matthew B. Dickinson; Lihong Su; Su Zhang; Daniel Yaussey
2010-01-01
The forest canopy is the medium for energy, mass, and momentum exchanges between the forest ecosystem and the atmosphere. Tree crown size is a critical aspect of canopy structure that significantly influences these biophysical processes in the canopy. Tree crown size is also strongly related to other canopy structural parameters, such as tree height, diameter at breast...
NASA Technical Reports Server (NTRS)
1974-01-01
The specifications and functions of the Central Data Processing (CDPF) Facility which supports the Earth Observatory Satellite (EOS) are discussed. The CDPF will receive the EOS sensor data and spacecraft data through the Spaceflight Tracking and Data Network (STDN) and the Operations Control Center (OCC). The CDPF will process the data and produce high density digital tapes, computer compatible tapes, film and paper print images, and other data products. The specific aspects of data inputs and data processing are identified. A block diagram of the CDPF to show the data flow and interfaces of the subsystems is provided.
Engineering workstation: Sensor modeling
NASA Technical Reports Server (NTRS)
Pavel, M; Sweet, B.
1993-01-01
The purpose of the engineering workstation is to provide an environment for rapid prototyping and evaluation of fusion and image processing algorithms. Ideally, the algorithms are designed to optimize the extraction of information that is useful to a pilot for all phases of flight operations. Successful design of effective fusion algorithms depends on the ability to characterize both the information available from the sensors and the information useful to a pilot. The workstation is comprised of subsystems for simulation of sensor-generated images, image processing, image enhancement, and fusion algorithms. As such, the workstation can be used to implement and evaluate both short-term solutions and long-term solutions. The short-term solutions are being developed to enhance a pilot's situational awareness by providing information in addition to his direct vision. The long term solutions are aimed at the development of complete synthetic vision systems. One of the important functions of the engineering workstation is to simulate the images that would be generated by the sensors. The simulation system is designed to use the graphics modeling and rendering capabilities of various workstations manufactured by Silicon Graphics Inc. The workstation simulates various aspects of the sensor-generated images arising from phenomenology of the sensors. In addition, the workstation can be used to simulate a variety of impairments due to mechanical limitations of the sensor placement and due to the motion of the airplane. Although the simulation is currently not performed in real-time, sequences of individual frames can be processed, stored, and recorded in a video format. In that way, it is possible to examine the appearance of different dynamic sensor-generated and fused images.
Multispectral simulation environment for modeling low-light-level sensor systems
NASA Astrophysics Data System (ADS)
Ientilucci, Emmett J.; Brown, Scott D.; Schott, John R.; Raqueno, Rolando V.
1998-11-01
Image intensifying cameras have been found to be extremely useful in low-light-level (LLL) scenarios including military night vision and civilian rescue operations. These sensors utilize the available visible region photons and an amplification process to produce high contrast imagery. It has been demonstrated that processing techniques can further enhance the quality of this imagery. For example, fusion with matching thermal IR imagery can improve image content when very little visible region contrast is available. To aid in the improvement of current algorithms and the development of new ones, a high fidelity simulation environment capable of producing radiometrically correct multi-band imagery for low- light-level conditions is desired. This paper describes a modeling environment attempting to meet these criteria by addressing the task as two individual components: (1) prediction of a low-light-level radiance field from an arbitrary scene, and (2) simulation of the output from a low- light-level sensor for a given radiance field. The radiance prediction engine utilized in this environment is the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model which is a first principles based multi-spectral synthetic image generation model capable of producing an arbitrary number of bands in the 0.28 to 20 micrometer region. The DIRSIG model is utilized to produce high spatial and spectral resolution radiance field images. These images are then processed by a user configurable multi-stage low-light-level sensor model that applies the appropriate noise and modulation transfer function (MTF) at each stage in the image processing chain. This includes the ability to reproduce common intensifying sensor artifacts such as saturation and 'blooming.' Additionally, co-registered imagery in other spectral bands may be simultaneously generated for testing fusion and exploitation algorithms. This paper discusses specific aspects of the DIRSIG radiance prediction for low- light-level conditions including the incorporation of natural and man-made sources which emphasizes the importance of accurate BRDF. A description of the implementation of each stage in the image processing and capture chain for the LLL model is also presented. Finally, simulated images are presented and qualitatively compared to lab acquired imagery from a commercial system.
High-volume workflow management in the ITN/FBI system
NASA Astrophysics Data System (ADS)
Paulson, Thomas L.
1997-02-01
The Identification Tasking and Networking (ITN) Federal Bureau of Investigation system will manage the processing of more than 70,000 submissions per day. The workflow manager controls the routing of each submission through a combination of automated and manual processing steps whose exact sequence is dynamically determined by the results at each step. For most submissions, one or more of the steps involve the visual comparison of fingerprint images. The ITN workflow manager is implemented within a scaleable client/server architecture. The paper describes the key aspects of the ITN workflow manager design which allow the high volume of daily processing to be successfully accomplished.
NASA Astrophysics Data System (ADS)
Alizadeh Savareh, Behrouz; Emami, Hassan; Hajiabadi, Mohamadreza; Ghafoori, Mahyar; Majid Azimi, Seyed
2018-03-01
Manual analysis of brain tumors magnetic resonance images is usually accompanied by some problem. Several techniques have been proposed for the brain tumor segmentation. This study will be focused on searching popular databases for related studies, theoretical and practical aspects of Convolutional Neural Network surveyed in brain tumor segmentation. Based on our findings, details about related studies including the datasets used, evaluation parameters, preferred architectures and complementary steps analyzed. Deep learning as a revolutionary idea in image processing, achieved brilliant results in brain tumor segmentation too. This can be continuing until the next revolutionary idea emerging.
Retinal imaging and image analysis.
Abràmoff, Michael D; Garvin, Mona K; Sonka, Milan
2010-01-01
Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships.
Retinal Imaging and Image Analysis
Abràmoff, Michael D.; Garvin, Mona K.; Sonka, Milan
2011-01-01
Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships. PMID:22275207
Application of separable parameter space techniques to multi-tracer PET compartment modeling.
Zhang, Jeff L; Michael Morey, A; Kadrmas, Dan J
2016-02-07
Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg-Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models.
Chatterjee, S; Mott, J H; Smyth, G; Dickson, S; Dobrowsky, W; Kelly, C G
2011-04-01
Intensity-modulated radiotherapy (IMRT) is increasingly being used to treat head and neck cancer cases. We discuss the clinical challenges associated with the setting up of an image guided intensity modulated radiotherapy service for a subset of head and neck cancer patients, using a recently commissioned helical tomotherapy (HT) Hi Art (Tomotherapy Inc, WI) machine in this article. We also discuss the clinical aspects of the tomotherapy planning process, treatment and image guidance experiences for the first 10 head and neck cancer cases. The concepts of geographical miss along with tomotherapy-specific effects, including that of field width and megavoltage CT (MVCT) imaging strategy, have been highlighted using the first 10 head and neck cases treated. There is a need for effective streamlining of all aspects of the service to ensure compliance with cancer waiting time targets. We discuss how patient toxicity audits are crucial to guide refinement of the newly set-up planning dose constraints. This article highlights the important clinical issues one must consider when setting up a head and neck IMRT, image-guided radiotherapy service. It shares some of the clinical challenges we have faced during the setting up of a tomotherapy service. Implementation of a clinical tomotherapy service requires a multidisciplinary team approach and relies heavily on good team working and effective communication between different staff groups.
Application of separable parameter space techniques to multi-tracer PET compartment modeling
NASA Astrophysics Data System (ADS)
Zhang, Jeff L.; Morey, A. Michael; Kadrmas, Dan J.
2016-02-01
Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg-Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models.
Jang, Jung Eun
2016-06-01
The purpose of this article is to present a sketch of a new image of pastoral care and counseling, which reflects the psychoanalytic understanding of the interacting transference and countertransference matrix, along with a process view of God in a mutually influencing relationship with creatures. A more effective approach in pastoral care and counseling can be conceptualized as the interactive play in which pastoral caregivers and receivers co-create a therapeutic relationship with their own past experiences and their creative capabilities. The interactive play is a concept of describing the mutually influencing relationship in the transference and countertransference interchange. The article introduces the concept of a persuasive God as a new image of pastoral care and counseling which includes aspects of the mutually interacting process in play. © The Author(s) 2016.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doughty, Benjamin; Simpson, Mary Jane; Yang, Bin
Our work aims to simplify multi-dimensional femtosecond transient absorption microscopy (TAM) data into decay associated amplitude maps that describe the spatial distributions of dynamical processes occurring on various characteristic timescales. Application of this method to TAM data obtained from a model methyl-ammonium lead iodide (CH 3NH 3PbI 3) perovskite thin film allows us to simplify the dataset consisting of a 68 time-resolved images into 4 decay associated amplitude maps. Furthermore, these maps provide a simple means to visualize the complex electronic excited-state dynamics in this system by separating distinct dynamical processes evolving on characteristic timescales into individual spatial images. Thismore » approach provides new insight into subtle aspects of ultrafast relaxation dynamics associated with excitons and charge carriers in the perovskite thin film, which have recently been found to coexist at spatially distinct locations.« less
NASA Astrophysics Data System (ADS)
Górna, K.; Jaśkowski, B. M.; Okoń, P.; Czechlowski, M.; Koszela, K.; Zaborowicz, M.; Idziaszek, P.
2017-07-01
The aim of the paper is to shown the neural image analysis as a method useful for identifying the development stage of the domestic bovine corpus luteum on digital USG (UltraSonoGraphy) images. Corpus luteum (CL) is a transient endocrine gland that develops after ovulation from the follicle secretory cells. The aim of CL is the production of progesterone, which regulates many reproductive functions. In the presented studies, identification of the corpus luteum was carried out on the basis of information contained in ultrasound digital images. Development stage of the corpus luteum was considered in two aspects: just before and middle of domination phase and luteolysis and degradation phase. Prior to the classification, the ultrasound images have been processed using a GLCM (Gray Level Co-occurence Matrix). To generate a classification model, a Neural Networks module implemented in the STATISTICA was used. Five representative parameters describing the ultrasound image were used as learner variables. On the output of the artificial neural network was generated information about the development stage of the corpus luteum. Results of this study indicate that neural image analysis combined with GLCM texture analysis may be a useful tool for identifying the bovine corpus luteum in the context of its development phase. Best-generated artificial neural network model was the structure of MLP (Multi Layer Perceptron) 5:5-17-1:1.
Interoceptive signals impact visual processing: Cardiac modulation of visual body perception.
Ronchi, Roberta; Bernasconi, Fosco; Pfeiffer, Christian; Bello-Ruiz, Javier; Kaliuzhna, Mariia; Blanke, Olaf
2017-09-01
Multisensory perception research has largely focused on exteroceptive signals, but recent evidence has revealed the integration of interoceptive signals with exteroceptive information. Such research revealed that heartbeat signals affect sensory (e.g., visual) processing: however, it is unknown how they impact the perception of body images. Here we linked our participants' heartbeat to visual stimuli and investigated the spatio-temporal brain dynamics of cardio-visual stimulation on the processing of human body images. We recorded visual evoked potentials with 64-channel electroencephalography while showing a body or a scrambled-body (control) that appeared at the frequency of the on-line recorded participants' heartbeat or not (not-synchronous, control). Extending earlier studies, we found a body-independent effect, with cardiac signals enhancing visual processing during two time periods (77-130 ms and 145-246 ms). Within the second (later) time-window we detected a second effect characterised by enhanced activity in parietal, temporo-occipital, inferior frontal, and right basal ganglia-insula regions, but only when non-scrambled body images were flashed synchronously with the heartbeat (208-224 ms). In conclusion, our results highlight the role of interoceptive information for the visual processing of human body pictures within a network integrating cardio-visual signals of relevance for perceptual and cognitive aspects of visual body processing. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
DeForest, Craig; Seaton, Daniel B.; Darnell, John A.
2017-08-01
I present and demonstrate a new, general purpose post-processing technique, "3D noise gating", that can reduce image noise by an order of magnitude or more without effective loss of spatial or temporal resolution in typical solar applications.Nearly all scientific images are, ultimately, limited by noise. Noise can be direct Poisson "shot noise" from photon counting effects, or introduced by other means such as detector read noise. Noise is typically represented as a random variable (perhaps with location- or image-dependent characteristics) that is sampled once per pixel or once per resolution element of an image sequence. Noise limits many aspects of image analysis, including photometry, spatiotemporal resolution, feature identification, morphology extraction, and background modeling and separation.Identifying and separating noise from image signal is difficult. The common practice of blurring in space and/or time works because most image "signal" is concentrated in the low Fourier components of an image, while noise is evenly distributed. Blurring in space and/or time attenuates the high spatial and temporal frequencies, reducing noise at the expense of also attenuating image detail. Noise-gating exploits the same property -- "coherence" -- that we use to identify features in images, to separate image features from noise.Processing image sequences through 3-D noise gating results in spectacular (more than 10x) improvements in signal-to-noise ratio, while not blurring bright, resolved features in either space or time. This improves most types of image analysis, including feature identification, time sequence extraction, absolute and relative photometry (including differential emission measure analysis), feature tracking, computer vision, correlation tracking, background modeling, cross-scale analysis, visual display/presentation, and image compression.I will introduce noise gating, describe the method, and show examples from several instruments (including SDO/AIA , SDO/HMI, STEREO/SECCHI, and GOES-R/SUVI) that explore the benefits and limits of the technique.
Image standards in tissue-based diagnosis (diagnostic surgical pathology).
Kayser, Klaus; Görtler, Jürgen; Goldmann, Torsten; Vollmer, Ekkehard; Hufnagl, Peter; Kayser, Gian
2008-04-18
Progress in automated image analysis, virtual microscopy, hospital information systems, and interdisciplinary data exchange require image standards to be applied in tissue-based diagnosis. To describe the theoretical background, practical experiences and comparable solutions in other medical fields to promote image standards applicable for diagnostic pathology. THEORY AND EXPERIENCES: Images used in tissue-based diagnosis present with pathology-specific characteristics. It seems appropriate to discuss their characteristics and potential standardization in relation to the levels of hierarchy in which they appear. All levels can be divided into legal, medical, and technological properties. Standards applied to the first level include regulations or aims to be fulfilled. In legal properties, they have to regulate features of privacy, image documentation, transmission, and presentation; in medical properties, features of disease-image combination, human-diagnostics, automated information extraction, archive retrieval and access; and in technological properties features of image acquisition, display, formats, transfer speed, safety, and system dynamics. The next lower second level has to implement the prescriptions of the upper one, i.e. describe how they are implemented. Legal aspects should demand secure encryption for privacy of all patient related data, image archives that include all images used for diagnostics for a period of 10 years at minimum, accurate annotations of dates and viewing, and precise hardware and software information. Medical aspects should demand standardized patients' files such as DICOM 3 or HL 7 including history and previous examinations, information of image display hardware and software, of image resolution and fields of view, of relation between sizes of biological objects and image sizes, and of access to archives and retrieval. Technological aspects should deal with image acquisition systems (resolution, colour temperature, focus, brightness, and quality evaluation procedures), display resolution data, implemented image formats, storage, cycle frequency, backup procedures, operation system, and external system accessibility. The lowest third level describes the permitted limits and threshold in detail. At present, an applicable standard including all mentioned features does not exist to our knowledge; some aspects can be taken from radiological standards (PACS, DICOM 3); others require specific solutions or are not covered yet. The progress in virtual microscopy and application of artificial intelligence (AI) in tissue-based diagnosis demands fast preparation and implementation of an internationally acceptable standard. The described hierarchic order as well as analytic investigation in all potentially necessary aspects and details offers an appropriate tool to specifically determine standardized requirements.
Study of the wide area of a lake with remote sensing
NASA Astrophysics Data System (ADS)
Lazaridou, Maria A.; Karagianni, Aikaterini C.
2016-08-01
Water bodies are particularly important for environment and development issues. Their study requires multiple information. Remote sensing has been proven useful in the above study. This paper concerns the wide area of Lake Orestiada in the region of Western Macedonia in Greece. The area is of particular interest because Lake Orestiada is included in the Natura 2000 network and is surrounded by diverse landcovers as built up areas and agricultural land. Multispectral and thermal Landsat 5 satellite images of two time periods are being used. Their processing is being done by Erdas Imagine software. The general physiognomy of the area and the lake shore are examined after image enhancement techniques and image interpretation. Directions of the study concern geomorphological aspects, land covers, estimation of surface temperature as well as changes through time.
Current Status and Future Perspectives of Mass Spectrometry Imaging
Nimesh, Surendra; Mohottalage, Susantha; Vincent, Renaud; Kumarathasan, Prem
2013-01-01
Mass spectrometry imaging is employed for mapping proteins, lipids and metabolites in biological tissues in a morphological context. Although initially developed as a tool for biomarker discovery by imaging the distribution of protein/peptide in tissue sections, the high sensitivity and molecular specificity of this technique have enabled its application to biomolecules, other than proteins, even in cells, latent finger prints and whole organisms. Relatively simple, with no requirement for labelling, homogenization, extraction or reconstitution, the technique has found a variety of applications in molecular biology, pathology, pharmacology and toxicology. By discriminating the spatial distribution of biomolecules in serial sections of tissues, biomarkers of lesions and the biological responses to stressors or diseases can be better understood in the context of structure and function. In this review, we have discussed the advances in the different aspects of mass spectrometry imaging processes, application towards different disciplines and relevance to the field of toxicology. PMID:23759983
On the Uncertain Future of the Volumetric 3D Display Paradigm
NASA Astrophysics Data System (ADS)
Blundell, Barry G.
2017-06-01
Volumetric displays permit electronically processed images to be depicted within a transparent physical volume and enable a range of cues to depth to be inherently associated with image content. Further, images can be viewed directly by multiple simultaneous observers who are able to change vantage positions in a natural way. On the basis of research to date, we assume that the technologies needed to implement useful volumetric displays able to support translucent image formation are available. Consequently, in this paper we review aspects of the volumetric paradigm and identify important issues which have, to date, precluded their successful commercialization. Potentially advantageous characteristics are outlined and demonstrate that significant research is still needed in order to overcome barriers which continue to hamper the effective exploitation of this display modality. Given the recent resurgence of interest in developing commercially viable general purpose volumetric systems, this discussion is of particular relevance.
Modeling Images of Natural 3D Surfaces: Overview and Potential Applications
NASA Technical Reports Server (NTRS)
Jalobeanu, Andre; Kuehnel, Frank; Stutz, John
2004-01-01
Generative models of natural images have long been used in computer vision. However, since they only describe the of 2D scenes, they fail to capture all the properties of the underlying 3D world. Even though such models are sufficient for many vision tasks a 3D scene model is when it comes to inferring a 3D object or its characteristics. In this paper, we present such a generative model, incorporating both a multiscale surface prior model for surface geometry and reflectance, and an image formation process model based on realistic rendering, the computation of the posterior model parameter densities, and on the critical aspects of the rendering. We also how to efficiently invert the model within a Bayesian framework. We present a few potential applications, such as asteroid modeling and Planetary topography recovery, illustrated by promising results on real images.
Quality initiatives: planning, setting up, and carrying out radiology process improvement projects.
Tamm, Eric P; Szklaruk, Janio; Puthooran, Leejo; Stone, Danna; Stevens, Brian L; Modaro, Cathy
2012-01-01
In the coming decades, those who provide radiologic imaging services will be increasingly challenged by the economic, demographic, and political forces affecting healthcare to improve their efficiency, enhance the value of their services, and achieve greater customer satisfaction. It is essential that radiologists master and consistently apply basic process improvement skills that have allowed professionals in many other fields to thrive in a competitive environment. The authors provide a step-by-step overview of process improvement from the perspective of a radiologic imaging practice by describing their experience in conducting a process improvement project: to increase the daily volume of body magnetic resonance imaging examinations performed at their institution. The first step in any process improvement project is to identify and prioritize opportunities for improvement in the work process. Next, an effective project team must be formed that includes representatives of all participants in the process. An achievable aim must be formulated, appropriate measures selected, and baseline data collected to determine the effects of subsequent efforts to achieve the aim. Each aspect of the process in question is then analyzed by using appropriate tools (eg, flowcharts, fishbone diagrams, Pareto diagrams) to identify opportunities for beneficial change. Plans for change are then established and implemented with regular measurements and review followed by necessary adjustments in course. These so-called PDSA (planning, doing, studying, and acting) cycles are repeated until the aim is achieved or modified and the project closed.
BOOK REVIEW: Image-Guided IMRT
NASA Astrophysics Data System (ADS)
Mayles, P.
2006-12-01
This book provides comprehensive coverage of the subject of intensity modulated radiotherapy and the associated imaging. Most of the names associated with advanced radiotherapy can be found among the 80 authors and the book is therefore an authoritative reference text. The early chapters deal with the basic principles and include an interesting comparison between views of quality assurance for IMRT from Europe and North America. It is refreshing to see that the advice given has moved on from the concept of individual patient based quality control to more generic testing of the delivery system. However, the point is made that the whole process including the data transfer needs to be quality assured and the need for thorough commissioning of the process is emphasised. The `tricks' needed to achieve a dose based IMRT plan are well covered by the group at Ghent and there is an interesting summary of biological aspects of treatment planning for IMRT by Andrzej Niemierko. The middle section of the book deals with advanced imaging aspects of both treatment planning and delivery. The contributions of PET and MR imaging are well covered and there is a rather rambling section on molecular imaging. Image guidance in radiotherapy treatment is addressed including the concept of adaptive radiotherapy. The treatment aspects could perhaps have merited some more coverage, but there is a very thorough discussion of 4D techniques. The final section of the book considers each site of the body in turn. This will be found useful by those wishing to embark on IMRT in a new area, although some of the sections are more comprehensive than others. The book contains a wealth of interesting and thought provoking articles giving details as well as broad principles, and would be a useful addition to every departmental library. The editors have done a good job of ensuring that the different chapters are complementary, and of encouraging a systematic approach to the descriptions of IMRT in different anatomical sites, each of which ends with a look ahead to the future. It is something of a challenge to keep a book devoted to a rapidly developing technique up to date. Inspection of the references suggests that most of the text was completed in 2004, but the choice of world renowned authors means that the text very much represents the state of the art. The book is well presented with many colour images and justifies its £110 price tag. However, there are some signs of it having been produced within a short time scale, such as an inadequate index which cannot be relied on to lead the reader to all, or even the most relevant, discussion on a particular topic. This book should make a significant contribution to widening the use of this important advance in radiation therapy techniques.
Technical aspects of dental CBCT: state of the art
Araki, K; Siewerdsen, J H; Thongvigitmanee, S S
2015-01-01
As CBCT is widely used in dental and maxillofacial imaging, it is important for users as well as referring practitioners to understand the basic concepts of this imaging modality. This review covers the technical aspects of each part of the CBCT imaging chain. First, an overview is given of the hardware of a CBCT device. The principles of cone beam image acquisition and image reconstruction are described. Optimization of imaging protocols in CBCT is briefly discussed. Finally, basic and advanced visualization methods are illustrated. Certain topics in these review are applicable to all types of radiographic imaging (e.g. the principle and properties of an X-ray tube), others are specific for dental CBCT imaging (e.g. advanced visualization techniques). PMID:25263643
Image-guided positioning and tracking.
Ruan, Dan; Kupelian, Patrick; Low, Daniel A
2011-01-01
Radiation therapy aims at maximizing tumor control while minimizing normal tissue complication. The introduction of stereotactic treatment explores the volume effect and achieves dose escalation to tumor target with small margins. The use of ablative irradiation dose and sharp dose gradients requires accurate tumor definition and alignment between patient and treatment geometry. Patient geometry variation during treatment may significantly compromise the conformality of delivered dose and must be managed properly. Setup error and interfraction/intrafraction motion are incorporated in the target definition process by expanding the clinical target volume to planning target volume, whereas the alignment between patient and treatment geometry is obtained with an adaptive control process, by taking immediate actions in response to closely monitored patient geometry. This article focuses on the monitoring and adaptive response aspect of the problem. The term "image" in "image guidance" will be used in a most general sense, to be inclusive of some important point-based monitoring systems that can be considered as degenerate cases of imaging. Image-guided motion adaptive control, as a comprehensive system, involves a hierarchy of decisions, each of which balances simplicity versus flexibility and accuracy versus robustness. Patient specifics and machine specifics at the treatment facility also need to be incorporated into the decision-making process. Identifying operation bottlenecks from a system perspective and making informed compromises are crucial in the proper selection of image-guidance modality, the motion management mechanism, and the respective operation modes. Not intended as an exhaustive exposition, this article focuses on discussing the major issues and development principles for image-guided motion management systems. We hope these information and methodologies will facilitate conscientious practitioners to adopt image-guided motion management systems accounting for patient and institute specifics and to embrace advances in knowledge and new technologies subsequent to the publication of this article.
Adaptation of in-situ microscopy for crystallization processes
NASA Astrophysics Data System (ADS)
Bluma, A.; Höpfner, T.; Rudolph, G.; Lindner, P.; Beutel, S.; Hitzmann, B.; Scheper, T.
2009-08-01
In biotechnological and pharmaceutical engineering, the study of crystallization processes gains importance. An efficient analytical inline sensor could help to improve the knowledge about these processes in order to increase efficiency and yields. The in-situ microscope (ISM) is an optical sensor developed for the monitoring of bioprocesses. A new application for this sensor is the monitoring in downstream processes, e.g. the crystallization of proteins and other organic compounds. This contribution shows new aspects of using in-situ microscopy to monitor crystallization processes. Crystals of different chemical compounds were precipitated from supersaturated solutions and the crystal growth was monitored. Exemplified morphological properties and different forms of crystals could be distinguished on the basis of offline experiments. For inline monitoring of crystallization processes, a special 0.5 L stirred tank reactor was developed and equipped with the in-situ microscope. This reactor was utilized to carry out batch experiments for crystallizations of O-acetylsalicyclic acid (ASS) and hen egg white lysozyme (HEWL). During the whole crystallization process, the in-situ microscope system acquired images directly from the crystallization broth. For the data evaluation, an image analysis algorithm was developed and implemented in the microscope analysis software.
Menning, Sanne; de Ruiter, Michiel B; Veltman, Dick J; Koppelmans, V; Kirschbaum, Clemens; Boogerd, Willem; Reneman, Liesbeth; Schagen, Sanne B
2015-01-01
An increasing body of literature indicates that chemotherapy (ChT) for breast cancer (BC) is associated with adverse effects on the brain. Recent research suggests that cognitive and brain function in patients with BC may already be compromised before the start of chemotherapy. This is the first study combining neuropsychological testing, patient-reported outcomes, and multimodal magnetic resonance imaging (MRI) to examine pretreatment cognition and various aspects of brain function and structure in a large sample. Thirty-two patients with BC scheduled to receive ChT (pre-ChT+), 33 patients with BC not indicated to undergo ChT (pre-ChT-), and 38 no-cancer controls (NCs) were included. The examination consisted of a neuropsychological test battery, self-reported aspects of psychosocial functioning, and multimodal MRI. Patients with BC reported worse scores on several aspects of quality of life, such as higher levels of fatigue and stress. However, cortisol levels were not elevated in the patient groups compared to the control group. Overall cognitive performance was lower in the pre-ChT+ and the pre-ChT- groups compared to NC. Further, patients demonstrated prefrontal hyperactivation with increasing task difficulty on a planning task compared to NC, but not during a memory task. White matter integrity was lower in both patient groups. No differences in regional brain volume and brain metabolites were found. The cognitive and imaging data converged to show that symptoms of fatigue were associated with the observed abnormalities; the observed differences were no longer significant when fatigue was accounted for. This study suggests that cancer-related psychological or biological processes may adversely impact cognitive functioning and associated aspects of brain structure and function before the start of adjuvant treatment. Our findings stress the importance to further explore the processes underlying the expression of fatigue and to study whether it has a contributory role in subsequent treatment-related cognitive decline.
Some new classification methods for hyperspectral remote sensing
NASA Astrophysics Data System (ADS)
Du, Pei-jun; Chen, Yun-hao; Jones, Simon; Ferwerda, Jelle G.; Chen, Zhi-jun; Zhang, Hua-peng; Tan, Kun; Yin, Zuo-xia
2006-10-01
Hyperspectral Remote Sensing (HRS) is one of the most significant recent achievements of Earth Observation Technology. Classification is the most commonly employed processing methodology. In this paper three new hyperspectral RS image classification methods are analyzed. These methods are: Object-oriented FIRS image classification, HRS image classification based on information fusion and HSRS image classification by Back Propagation Neural Network (BPNN). OMIS FIRS image is used as the example data. Object-oriented techniques have gained popularity for RS image classification in recent years. In such method, image segmentation is used to extract the regions from the pixel information based on homogeneity criteria at first, and spectral parameters like mean vector, texture, NDVI and spatial/shape parameters like aspect ratio, convexity, solidity, roundness and orientation for each region are calculated, finally classification of the image using the region feature vectors and also using suitable classifiers such as artificial neural network (ANN). It proves that object-oriented methods can improve classification accuracy since they utilize information and features both from the point and the neighborhood, and the processing unit is a polygon (in which all pixels are homogeneous and belong to the class). HRS image classification based on information fusion, divides all bands of the image into different groups initially, and extracts features from every group according to the properties of each group. Three levels of information fusion: data level fusion, feature level fusion and decision level fusion are used to HRS image classification. Artificial Neural Network (ANN) can perform well in RS image classification. In order to promote the advances of ANN used for HIRS image classification, Back Propagation Neural Network (BPNN), the most commonly used neural network, is used to HRS image classification.
Improved 3D seismic images of dynamic deformation in the Nankai Trough off Kumano
NASA Astrophysics Data System (ADS)
Shiraishi, K.; Moore, G. F.; Yamada, Y.; Kinoshita, M.; Sanada, Y.; Kimura, G.
2016-12-01
In order to improve the seismic reflection image of dynamic deformation and seismogenic faults in the Nankai trough, the 2006 Kumano 3D seismic dataset was reprocessed from the original field records by applying advanced technologies a decade after the data acquisition and initial processing. The 3D seismic survey revealed the geometry of megasplay fault system. However, there were still unclear regions in the accretionary prism beneath from Kumano basin to the outer ridge, because of sea floor multiple reflections and noise caused by the Kuroshio current. For the next stage of deep scientific drilling into the Nankai trough seismogenic zone, it is essential to know exactly the shape and depth of the megasplay, and fine structures around the drilling site. Three important improvements were achieved in data processing before imaging. First, full deghosting and optimized zero phasing techniques could recover broadband signals, especially in low frequency, by compensating for ghost effects at both source and receiver, and removing source bubbles. Second, the multiple reflections better attenuated by applying advanced techniques in combination, and the strong noise caused by the Kuroshio were attenuated carefully. Third, data regularization by means of the optimized 4D trace interpolation was effective both to mitigate non-uniform fold distribution and to improve data quality. Further imaging processes led to obvious improvement from previous results by applying PSTM with higher order correction of VTI anisotropy, and PSDM based on the velocity model built by reflection tomography with TTI anisotropy. Final reflection images show new geological aspects, such as clear steep dip faults around the "notch", and fine scale faults related to main thrusts in frontal thrust zone. The improved images will highly contribute to understanding the deformation process in the old accretionary prism and seismogenic features related to the megasplay faults.
Stereoscopic Machine-Vision System Using Projected Circles
NASA Technical Reports Server (NTRS)
Mackey, Jeffrey R.
2010-01-01
A machine-vision system capable of detecting obstacles large enough to damage or trap a robotic vehicle is undergoing development. The system includes (1) a pattern generator that projects concentric circles of laser light forward onto the terrain, (2) a stereoscopic pair of cameras that are aimed forward to acquire images of the circles, (3) a frame grabber and digitizer for acquiring image data from the cameras, and (4) a single-board computer that processes the data. The system is being developed as a prototype of machine- vision systems to enable robotic vehicles ( rovers ) on remote planets to avoid craters, large rocks, and other terrain features that could capture or damage the vehicles. Potential terrestrial applications of systems like this one could include terrain mapping, collision avoidance, navigation of robotic vehicles, mining, and robotic rescue. This system is based partly on the same principles as those of a prior stereoscopic machine-vision system in which the cameras acquire images of a single stripe of laser light that is swept forward across the terrain. However, this system is designed to afford improvements over some of the undesirable features of the prior system, including the need for a pan-and-tilt mechanism to aim the laser to generate the swept stripe, ambiguities in interpretation of the single-stripe image, the time needed to sweep the stripe across the terrain and process the data from many images acquired during that time, and difficulty of calibration because of the narrowness of the stripe. In this system, the pattern generator does not contain any moving parts and need not be mounted on a pan-and-tilt mechanism: the pattern of concentric circles is projected steadily in the forward direction. The system calibrates itself by use of data acquired during projection of the concentric-circle pattern onto a known target representing flat ground. The calibration- target image data are stored in the computer memory for use as a template in processing terrain images. During operation on terrain, the images acquired by the left and right cameras are analyzed. The analysis includes (1) computation of the horizontal and vertical dimensions and the aspect ratios of rectangles that bound the circle images and (2) comparison of these aspect ratios with those of the template. Coordinates of distortions of the circles are used to identify and locate objects. If the analysis leads to identification of an object of significant size, then stereoscopicvision algorithms are used to estimate the distance to the object. The time taken in performing this analysis on a single pair of images acquired by the left and right cameras in this system is a fraction of the time taken in processing the many pairs of images acquired in a sweep of the laser stripe across the field of view in the prior system. The results of the analysis include data on sizes and shapes of, and distances and directions to, objects. Coordinates of objects are updated as the vehicle moves so that intelligent decisions regarding speed and direction can be made. The results of the analysis are utilized in a computational decision-making process that generates obstacle-avoidance data and feeds those data to the control system of the robotic vehicle.
[Aged subjects' personal image of elderly people].
Oswald, F
1991-01-01
Many findings demonstrate a negative image toward old people in our society. "Being-old" is characterised by many negative stereotypes. The elderly are often seen as victims or targets of discrimination against the aged ("ageism"). We also find self-discrimination in the elderly's image of "being-old"; this could be a result of assimilating the general image of "being-old" in our society to the self-concept of the elderly. We asked 30 persons, 63-96 years old, to give a description of "being-old". Our participants differed in sex, health status, and social housing conditions (number of persons living together). The given aspects of "being-old" had to be semantically described and evaluated. We got 279 aspects of "being-old" which we put into 13 categories. We did not find a generally negative image of "being-old". All participants did not assess themselves as being "old", regardless of their age. The most frequently cited aspects of "being-old" were "physical and mental activity", "achievement-relation" and "autonomy", but not "disease" or "decrease of power". As far as they are concerned, aspects of "having time and calmness" were more often mentioned than aspects of "being-religious" or thinking about "dying and death". Participants living with their partners or family members more often talked about themselves than singles did when they explained a given aspect of "being-old" to the interviewer. Those who live without health problems more often talked about diseases than ill participants did. Women more frequently explained self evaluation of health problems to the interviewer than men.
NASA Astrophysics Data System (ADS)
Cipriani, L.; Fantini, F.; Bertacchi, S.
2014-06-01
Image-based modelling tools based on SfM algorithms gained great popularity since several software houses provided applications able to achieve 3D textured models easily and automatically. The aim of this paper is to point out the importance of controlling models parameterization process, considering that automatic solutions included in these modelling tools can produce poor results in terms of texture utilization. In order to achieve a better quality of textured models from image-based modelling applications, this research presents a series of practical strategies aimed at providing a better balance between geometric resolution of models from passive sensors and their corresponding (u,v) map reference systems. This aspect is essential for the achievement of a high-quality 3D representation, since "apparent colour" is a fundamental aspect in the field of Cultural Heritage documentation. Complex meshes without native parameterization have to be "flatten" or "unwrapped" in the (u,v) parameter space, with the main objective to be mapped with a single image. This result can be obtained by using two different strategies: the former automatic and faster, while the latter manual and time-consuming. Reverse modelling applications provide automatic solutions based on splitting the models by means of different algorithms, that produce a sort of "atlas" of the original model in the parameter space, in many instances not adequate and negatively affecting the overall quality of representation. Using in synergy different solutions, ranging from semantic aware modelling techniques to quad-dominant meshes achieved using retopology tools, it is possible to obtain a complete control of the parameterization process.
Qualitative and quantitative processing of side-scan sonar data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dwan, F.S.; Anderson, A.L.; Hilde, T.W.C.
1990-06-01
Modern side-scan sonar systems allow vast areas of seafloor to be rapidly imaged and quantitatively mapped in detail. The application of remote sensing image processing techniques can be used to correct for various distortions inherent in raw sonography. Corrections are possible for water column, slant-range, aspect ratio, speckle and striping noise, multiple returns, power drop-off, and for georeferencing. The final products reveal seafloor features and patterns that are geometrically correct, georeferenced, and have improved signal/noise ratio. These products can be merged with other georeferenced data bases for further database management and information extraction. In order to compare data collected bymore » different systems from a common area and to ground truth measurements and geoacoustic models, quantitative correction must be made for calibrated sonar system and bathymetry effects. Such data inversion must account for system source level, beam pattern, time-varying gain, processing gain, transmission loss, absorption, insonified area, and grazing angle effects. Seafloor classification can then be performed on the calculated back-scattering strength using Lambert's Law and regression analysis. Examples are given using both approaches: image analysis and inversion of data based on the sonar equation.« less
Sadness is unique: neural processing of emotions in speech prosody in musicians and non-musicians.
Park, Mona; Gutyrchik, Evgeny; Welker, Lorenz; Carl, Petra; Pöppel, Ernst; Zaytseva, Yuliya; Meindl, Thomas; Blautzik, Janusch; Reiser, Maximilian; Bao, Yan
2014-01-01
Musical training has been shown to have positive effects on several aspects of speech processing, however, the effects of musical training on the neural processing of speech prosody conveying distinct emotions are yet to be better understood. We used functional magnetic resonance imaging (fMRI) to investigate whether the neural responses to speech prosody conveying happiness, sadness, and fear differ between musicians and non-musicians. Differences in processing of emotional speech prosody between the two groups were only observed when sadness was expressed. Musicians showed increased activation in the middle frontal gyrus, the anterior medial prefrontal cortex, the posterior cingulate cortex and the retrosplenial cortex. Our results suggest an increased sensitivity of emotional processing in musicians with respect to sadness expressed in speech, possibly reflecting empathic processes.
A forensic science perspective on the role of images in crime investigation and reconstruction.
Milliet, Quentin; Delémont, Olivier; Margot, Pierre
2014-12-01
This article presents a global vision of images in forensic science. The proliferation of perspectives on the use of images throughout criminal investigations and the increasing demand for research on this topic seem to demand a forensic science-based analysis. In this study, the definitions of and concepts related to material traces are revisited and applied to images, and a structured approach is used to persuade the scientific community to extend and improve the use of images as traces in criminal investigations. Current research efforts focus on technical issues and evidence assessment. This article provides a sound foundation for rationalising and explaining the processes involved in the production of clues from trace images. For example, the mechanisms through which these visual traces become clues of presence or action are described. An extensive literature review of forensic image analysis emphasises the existing guidelines and knowledge available for answering investigative questions (who, what, where, when and how). However, complementary developments are still necessary to demystify many aspects of image analysis in forensic science, including how to review and select images or use them to reconstruct an event or assist intelligence efforts. The hypothetico-deductive reasoning pathway used to discover unknown elements of an event or crime can also help scientists understand the underlying processes involved in their decision making. An analysis of a single image in an investigative or probative context is used to demonstrate the highly informative potential of images as traces and/or clues. Research efforts should be directed toward formalising the extraction and combination of clues from images. An appropriate methodology is key to expanding the use of images in forensic science. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.
Quantitative fluorescence microscopy and image deconvolution.
Swedlow, Jason R
2013-01-01
Quantitative imaging and image deconvolution have become standard techniques for the modern cell biologist because they can form the basis of an increasing number of assays for molecular function in a cellular context. There are two major types of deconvolution approaches--deblurring and restoration algorithms. Deblurring algorithms remove blur but treat a series of optical sections as individual two-dimensional entities and therefore sometimes mishandle blurred light. Restoration algorithms determine an object that, when convolved with the point-spread function of the microscope, could produce the image data. The advantages and disadvantages of these methods are discussed in this chapter. Image deconvolution in fluorescence microscopy has usually been applied to high-resolution imaging to improve contrast and thus detect small, dim objects that might otherwise be obscured. Their proper use demands some consideration of the imaging hardware, the acquisition process, fundamental aspects of photon detection, and image processing. This can prove daunting for some cell biologists, but the power of these techniques has been proven many times in the works cited in the chapter and elsewhere. Their usage is now well defined, so they can be incorporated into the capabilities of most laboratories. A major application of fluorescence microscopy is the quantitative measurement of the localization, dynamics, and interactions of cellular factors. The introduction of green fluorescent protein and its spectral variants has led to a significant increase in the use of fluorescence microscopy as a quantitative assay system. For quantitative imaging assays, it is critical to consider the nature of the image-acquisition system and to validate its response to known standards. Any image-processing algorithms used before quantitative analysis should preserve the relative signal levels in different parts of the image. A very common image-processing algorithm, image deconvolution, is used to remove blurred signal from an image. There are two major types of deconvolution approaches, deblurring and restoration algorithms. Deblurring algorithms remove blur, but treat a series of optical sections as individual two-dimensional entities, and therefore sometimes mishandle blurred light. Restoration algorithms determine an object that, when convolved with the point-spread function of the microscope, could produce the image data. The advantages and disadvantages of these methods are discussed. Copyright © 1998 Elsevier Inc. All rights reserved.
Image-guided radiation therapy in lymphoma management
Eng, Tony
2015-01-01
Image-guided radiation therapy (IGRT) is a process of incorporating imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), Positron emission tomography (PET), and ultrasound (US) during radiation therapy (RT) to improve treatment accuracy. It allows real-time or near real-time visualization of anatomical information to ensure that the target is in its position as planned. In addition, changes in tumor volume and location due to organ motion during treatment can be also compensated. IGRT has been gaining popularity and acceptance rapidly in RT over the past 10 years, and many published data have been reported on prostate, bladder, head and neck, and gastrointestinal cancers. However, the role of IGRT in lymphoma management is not well defined as there are only very limited published data currently available. The scope of this paper is to review the current use of IGRT in the management of lymphoma. The technical and clinical aspects of IGRT, lymphoma imaging studies, the current role of IGRT in lymphoma management and future directions will be discussed. PMID:26484299
Securing Color Fidelity in 3D Architectural Heritage Scenarios.
Gaiani, Marco; Apollonio, Fabrizio Ivan; Ballabeni, Andrea; Remondino, Fabio
2017-10-25
Ensuring color fidelity in image-based 3D modeling of heritage scenarios is nowadays still an open research matter. Image colors are important during the data processing as they affect algorithm outcomes, therefore their correct treatment, reduction and enhancement is fundamental. In this contribution, we present an automated solution developed to improve the radiometric quality of an image datasets and the performances of two main steps of the photogrammetric pipeline (camera orientation and dense image matching). The suggested solution aims to achieve a robust automatic color balance and exposure equalization, stability of the RGB-to-gray image conversion and faithful color appearance of a digitized artifact. The innovative aspects of the article are: complete automation, better color target detection, a MATLAB implementation of the ACR scripts created by Fraser and the use of a specific weighted polynomial regression. A series of tests are presented to demonstrate the efficiency of the developed methodology and to evaluate color accuracy ('color characterization').
Multispectral laser imaging for advanced food analysis
NASA Astrophysics Data System (ADS)
Senni, L.; Burrascano, P.; Ricci, M.
2016-07-01
A hardware-software apparatus for food inspection capable of realizing multispectral NIR laser imaging at four different wavelengths is herein discussed. The system was designed to operate in a through-transmission configuration to detect the presence of unwanted foreign bodies inside samples, whether packed or unpacked. A modified Lock-In technique was employed to counterbalance the significant signal intensity attenuation due to transmission across the sample and to extract the multispectral information more efficiently. The NIR laser wavelengths used to acquire the multispectral images can be varied to deal with different materials and to focus on specific aspects. In the present work the wavelengths were selected after a preliminary analysis to enhance the image contrast between foreign bodies and food in the sample, thus identifying the location and nature of the defects. Experimental results obtained from several specimens, with and without packaging, are presented and the multispectral image processing as well as the achievable spatial resolution of the system are discussed.
Securing Color Fidelity in 3D Architectural Heritage Scenarios
Apollonio, Fabrizio Ivan; Ballabeni, Andrea; Remondino, Fabio
2017-01-01
Ensuring color fidelity in image-based 3D modeling of heritage scenarios is nowadays still an open research matter. Image colors are important during the data processing as they affect algorithm outcomes, therefore their correct treatment, reduction and enhancement is fundamental. In this contribution, we present an automated solution developed to improve the radiometric quality of an image datasets and the performances of two main steps of the photogrammetric pipeline (camera orientation and dense image matching). The suggested solution aims to achieve a robust automatic color balance and exposure equalization, stability of the RGB-to-gray image conversion and faithful color appearance of a digitized artifact. The innovative aspects of the article are: complete automation, better color target detection, a MATLAB implementation of the ACR scripts created by Fraser and the use of a specific weighted polynomial regression. A series of tests are presented to demonstrate the efficiency of the developed methodology and to evaluate color accuracy (‘color characterization’). PMID:29068359
Isolating contour information from arbitrary images
NASA Technical Reports Server (NTRS)
Jobson, Daniel J.
1989-01-01
Aspects of natural vision (physiological and perceptual) serve as a basis for attempting the development of a general processing scheme for contour extraction. Contour information is assumed to be central to visual recognition skills. While the scheme must be regarded as highly preliminary, initial results do compare favorably with the visual perception of structure. The scheme pays special attention to the construction of a smallest scale circular difference-of-Gaussian (DOG) convolution, calibration of multiscale edge detection thresholds with the visual perception of grayscale boundaries, and contour/texture discrimination methods derived from fundamental assumptions of connectivity and the characteristics of printed text. Contour information is required to fall between a minimum connectivity limit and maximum regional spatial density limit at each scale. Results support the idea that contour information, in images possessing good image quality, is (centered at about 10 cyc/deg and 30 cyc/deg). Further, lower spatial frequency channels appear to play a major role only in contour extraction from images with serious global image defects.
Developing Low-Noise GaAs JFETs For Cryogenic Operation
NASA Technical Reports Server (NTRS)
Cunningham, Thomas J.
1995-01-01
Report discusses aspects of effort to develop low-noise, low-gate-leakage gallium arsenide-based junction field-effect transistors (JFETs) for operation at temperature of about 4 K as readout amplifiers and multiplexing devices for infrared-imaging devices. Transistors needed to replace silicon transistors, relatively noisy at 4 K. Report briefly discusses basic physical principles of JFETs and describes continuing process of optimization of designs of GaAs JFETs for cryogenic operation.
Segmentation of anatomical structures of the heart based on echocardiography
NASA Astrophysics Data System (ADS)
Danilov, V. V.; Skirnevskiy, I. P.; Gerget, O. M.
2017-01-01
Nowadays, many practical applications in the field of medical image processing require valid and reliable segmentation of images in the capacity of input data. Some of the commonly used imaging techniques are ultrasound, CT, and MRI. However, the main difference between the other medical imaging equipment and EchoCG is that it is safer, low cost, non-invasive and non-traumatic. Three-dimensional EchoCG is a non-invasive imaging modality that is complementary and supplementary to two-dimensional imaging and can be used to examine the cardiovascular function and anatomy in different medical settings. The challenging problems, presented by EchoCG image processing, such as speckle phenomena, noise, temporary non-stationarity of processes, unsharp boundaries, attenuation, etc. forced us to consider and compare existing methods and then to develop an innovative approach that can tackle the problems connected with clinical applications. Actual studies are related to the analysis and development of a cardiac parameters automatic detection system by EchoCG that will provide new data on the dynamics of changes in cardiac parameters and improve the accuracy and reliability of the diagnosis. Research study in image segmentation has highlighted the capabilities of image-based methods for medical applications. The focus of the research is both theoretical and practical aspects of the application of the methods. Some of the segmentation approaches can be interesting for the imaging and medical community. Performance evaluation is carried out by comparing the borders, obtained from the considered methods to those manually prescribed by a medical specialist. Promising results demonstrate the possibilities and the limitations of each technique for image segmentation problems. The developed approach allows: to eliminate errors in calculating the geometric parameters of the heart; perform the necessary conditions, such as speed, accuracy, reliability; build a master model that will be an indispensable assistant for operations on a beating heart.
Torres, Ana M; Lopez, Jose J; Pueo, Basilio; Cobos, Maximo
2013-04-01
Plane-wave decomposition (PWD) methods using microphone arrays have been shown to be a very useful tool within the applied acoustics community for their multiple applications in room acoustics analysis and synthesis. While many theoretical aspects of PWD have been previously addressed in the literature, the practical advantages of the PWD method to assess the acoustic behavior of real rooms have been barely explored so far. In this paper, the PWD method is employed to analyze the sound field inside a selected set of real rooms having a well-defined purpose. To this end, a circular microphone array is used to capture and process a number of impulse responses at different spatial positions, providing angle-dependent data for both direct and reflected wavefronts. The detection of reflected plane waves is performed by means of image processing techniques applied over the raw array response data and over the PWD data, showing the usefulness of image-processing-based methods for room acoustics analysis.
Wu, Jyh Ming; Chen, Yi-Ru; Lin, Yu-Hung
2011-03-01
We are the first group to use a simple direct ultraviolet light (UV, λ=365 nm, I=76 mW cm(-2)) in a decomposition process to fabricate ZnO nanowires on a flexible substrate using a zinc acetylacetonate hydrate precursor in ambient air. ZnO nanocrystal (or nanowire) production only requires three to ten minutes. A field emission scanning electron microscopy (FESEM) image reveals a high aspect ratio of the ZnO nanowires, which are grown on a substrate with a diameter of ∼50-100 nm, and a length of up to several hundred microns. High resolution transmission electron microscopy (HRTEM) images reveal that the nanowires consist of many single crystalline ZnO nanoparticles that grow along the c axis, which suggests an oriented attachment process. A potential application for flexible UV photodetectors was investigated using a UV lamp (λ=365 nm, I=2.34 mW cm(-2)). A significant ratio of photocurrent to dark current--around 11,300%--was achieved.
Exploiting spectral content for image segmentation in GPR data
NASA Astrophysics Data System (ADS)
Wang, Patrick K.; Morton, Kenneth D., Jr.; Collins, Leslie M.; Torrione, Peter A.
2011-06-01
Ground-penetrating radar (GPR) sensors provide an effective means for detecting changes in the sub-surface electrical properties of soils, such as changes indicative of landmines or other buried threats. However, most GPR-based pre-screening algorithms only localize target responses along the surface of the earth, and do not provide information regarding an object's position in depth. As a result, feature extraction algorithms are forced to process data from entire cubes of data around pre-screener alarms, which can reduce feature fidelity and hamper performance. In this work, spectral analysis is investigated as a method for locating subsurface anomalies in GPR data. In particular, a 2-D spatial/frequency decomposition is applied to pre-screener flagged GPR B-scans. Analysis of these spatial/frequency regions suggests that aspects (e.g. moments, maxima, mode) of the frequency distribution of GPR energy can be indicative of the presence of target responses. After translating a GPR image to a function of the spatial/frequency distributions at each pixel, several image segmentation approaches can be applied to perform segmentation in this new transformed feature space. To illustrate the efficacy of the approach, a performance comparison between feature processing with and without the image segmentation algorithm is provided.
Microwave synthesis and photocatalytic activities of ZnO bipods with different aspect ratios
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Fazhe; Zhao, Zengdian; Qiao, Xueliang, E-mail: xuelqiao@163.com
2016-02-15
Highlights: • We synthesized linked ZnO nanorods by a facile microwave method. • The effect of reaction parameters on ZnO was investigated. • ZnO bipods with different aspect ratios were prepared. • The photocatalytic performance of ZnO bipods was evaluated. - Abstract: Linked ZnO nanorods have been successfully prepared via a facile microwave method without any post-synthesis treatment. The X-ray diffraction (XRD) patterns indicated the precursor had completely transformed into the pure ZnO crystal. The images of field emitting scanning electron microscope (FESEM) and transmission electron microscope (TEM) showed that linked ZnO nanorods consisted predominantly of ZnO bipods. The formationmore » process of the ZnO bipods was clearly discussed. ZnO bipods with different aspect ratios have been obtained by tuning the concentrations of reagents and microwave power. Moreover, the photocatalytic performance of ZnO bipods with different aspect ratios for degradation of methylene blue was systematically evaluated. The results of photocatalytic experiments showed that the photocatalytic activity increased with the aspect ratios of ZnO bipods increased. The reason is that ZnO bipods with larger aspect ratio have higher surface area, which can absorb more MB molecules to react with ·OH radicals.« less
Feasibility of Rapid Multitracer PET Tumor Imaging
NASA Astrophysics Data System (ADS)
Kadrmas, D. J.; Rust, T. C.
2005-10-01
Positron emission tomography (PET) can characterize different aspects of tumor physiology using various tracers. PET scans are usually performed using only one tracer since there is no explicit signal for distinguishing multiple tracers. We tested the feasibility of rapidly imaging multiple PET tracers using dynamic imaging techniques, where the signals from each tracer are separated based upon differences in tracer half-life, kinetics, and distribution. Time-activity curve populations for FDG, acetate, ATSM, and PTSM were simulated using appropriate compartment models, and noisy dual-tracer curves were computed by shifting and adding the single-tracer curves. Single-tracer components were then estimated from dual-tracer data using two methods: principal component analysis (PCA)-based fits of single-tracer components to multitracer data, and parallel multitracer compartment models estimating single-tracer rate parameters from multitracer time-activity curves. The PCA analysis found that there is information content present for separating multitracer data, and that tracer separability depends upon tracer kinetics, injection order and timing. Multitracer compartment modeling recovered rate parameters for individual tracers with good accuracy but somewhat higher statistical uncertainty than single-tracer results when the injection delay was >10 min. These approaches to processing rapid multitracer PET data may potentially provide a new tool for characterizing multiple aspects of tumor physiology in vivo.
Green, Walton A.; Little, Stefan A.; Price, Charles A.; Wing, Scott L.; Smith, Selena Y.; Kotrc, Benjamin; Doria, Gabriela
2014-01-01
The reticulate venation that is characteristic of a dicot leaf has excited interest from systematists for more than a century, and from physiological and developmental botanists for decades. The tools of digital image acquisition and computer image analysis, however, are only now approaching the sophistication needed to quantify aspects of the venation network found in real leaves quickly, easily, accurately, and reliably enough to produce biologically meaningful data. In this paper, we examine 120 leaves distributed across vascular plants (representing 118 genera and 80 families) using two approaches: a semiquantitative scoring system called “leaf ranking,” devised by the late Leo Hickey, and an automated image-analysis protocol. In the process of comparing these approaches, we review some methodological issues that arise in trying to quantify a vein network, and discuss the strengths and weaknesses of automatic data collection and human pattern recognition. We conclude that subjective leaf rank provides a relatively consistent, semiquantitative measure of areole size among other variables; that modal areole size is generally consistent across large sections of a leaf lamina; and that both approaches—semiquantitative, subjective scoring; and fully quantitative, automated measurement—have appropriate places in the study of leaf venation. PMID:25202646
Scripes, Paola G; Yaparpalvi, Ravindra
2012-09-01
The usage of functional data in radiation therapy (RT) treatment planning (RTP) process is currently the focus of significant technical, scientific, and clinical development. Positron emission tomography (PET) using ((18)F) fluorodeoxyglucose is being increasingly used in RT planning in recent years. Fluorodeoxyglucose is the most commonly used radiotracer for diagnosis, staging, recurrent disease detection, and monitoring of tumor response to therapy (Lung Cancer 2012;76:344-349; Lung Cancer 2009;64:301-307; J Nucl Med 2008;49:532-540; J Nucl Med 2007;48:58S-67S). All the efforts to improve both PET and computed tomography (CT) image quality and, consequently, lesion detectability have a common objective to increase the accuracy in functional imaging and thus of coregistration into RT planning systems. In radiotherapy, improvement in target localization permits reduction of tumor margins, consequently reducing volume of normal tissue irradiated. Furthermore, smaller treated target volumes create the possibility of dose escalation, leading to increased chances of tumor cure and control. This article focuses on the technical aspects of PET/CT image acquisition, fusion, usage, and impact on the physics of RTP. The authors review the basic elements of RTP, modern radiation delivery, and the technical parameters of coregistration of PET/CT into RT computerized planning systems. Copyright © 2012 Elsevier Inc. All rights reserved.
Integer-ambiguity resolution in astronomy and geodesy
NASA Astrophysics Data System (ADS)
Lannes, A.; Prieur, J.-L.
2014-02-01
Recent theoretical developments in astronomical aperture synthesis have revealed the existence of integer-ambiguity problems. Those problems, which appear in the self-calibration procedures of radio imaging, have been shown to be similar to the nearest-lattice point (NLP) problems encountered in high-precision geodetic positioning and in global navigation satellite systems. In this paper we analyse the theoretical aspects of the matter and propose new methods for solving those NLP~problems. The related optimization aspects concern both the preconditioning stage, and the discrete-search stage in which the integer ambiguities are finally fixed. Our algorithms, which are described in an explicit manner, can easily be implemented. They lead to substantial gains in the processing time of both stages. Their efficiency was shown via intensive numerical tests.
Modeling the functional repair of nervous tissue in spinal cord injury
NASA Astrophysics Data System (ADS)
Mantila, Sara M.; Camp, Jon J.; Krych, Aaron J.; Robb, Richard A.
2004-05-01
Functional repair of traumatic spinal cord injury (SCI) is one of the most challenging goals in modern medicine. The annual incidence of SCI in the United States is approximately 11,000 new cases. The prevalence of people in the U.S. currently living with SCI is approximately 200,000. Exploring and understanding nerve regeneration in the central nervous system (CNS) is a critical first step in attempting to reverse the devastating consequences of SCI. At Mayo Clinic, a preliminary study of implants in the transected rat spinal cord model demonstrates potential for promoting axon regeneration. In collaborative research between neuroscientists and bioengineers, this procedure holds promise for solving two critical aspects of axon repair-providing a resorbable structural scaffold to direct focused axon repair, and delivery of relevant signaling molecules necessary to facilitate regeneration. In our preliminary study, regeneration in the rat's spinal cord was modeled in three dimensions utilizing an image processing software system developed in the Biomedical Imaging Resource at Mayo Clinic. Advanced methods for image registration, segmentation, and rendering were used. The raw images were collected at three different magnifications. After image processing the individual channels in the scaffold, axon bundles, and macrophages could be identified. Several axon bundles could be visualized and traced through the entire volume, suggesting axonal growth throughout the length of the scaffold. Such information could potentially allow researchers and physicians to better understand and improve the nerve regeneration process for individuals with SCI.
Speech processing asymmetry revealed by dichotic listening and functional brain imaging.
Hugdahl, Kenneth; Westerhausen, René
2016-12-01
In this article, we review research in our laboratory from the last 25 to 30 years on the neuronal basis for laterality of speech perception focusing on the upper, posterior parts of the temporal lobes, and its functional and structural connections to other brain regions. We review both behavioral and brain imaging data, with a focus on dichotic listening experiments, and using a variety of imaging modalities. The data have come in most parts from healthy individuals and from studies on normally functioning brain, although we also review a few selected clinical examples. We first review and discuss the structural model for the explanation of the right-ear advantage (REA) and left hemisphere asymmetry for auditory language processing. A common theme across many studies have been our interest in the interaction between bottom-up, stimulus-driven, and top-down, instruction-driven, aspects of hemispheric asymmetry, and how perceptual factors interact with cognitive factors to shape asymmetry of auditory language information processing. In summary, our research have shown laterality for the initial processing of consonant-vowel syllables, first observed as a behavioral REA when subjects are required to report which syllable of a dichotic syllable-pair they perceive. In subsequent work we have corroborated the REA with brain imaging, and have shown that the REA is modulated through both bottom-up manipulations of stimulus properties, like sound intensity, and top-down manipulations of cognitive properties, like attention focus. Copyright © 2015 Elsevier Ltd. All rights reserved.
Ventral striatal activity links adversity and reward processing in children.
Kamkar, Niki H; Lewis, Daniel J; van den Bos, Wouter; Morton, J Bruce
2017-08-01
Adversity impacts many aspects of psychological and physical development including reward-based learning and decision-making. Mechanisms relating adversity and reward processing in children, however, remain unclear. Here, we show that adversity is associated with potentiated learning from positive outcomes and impulsive decision-making, but unrelated to learning from negative outcomes. We then show via functional magnetic resonance imaging that the link between adversity and reward processing is partially mediated by differences in ventral striatal response to rewards. The findings suggest that early-life adversity is associated with alterations in the brain's sensitivity to rewards accounting, in part, for the link between adversity and altered reward processing in children. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Ultrasonographic anatomy of the dorsal and abaxial aspects of the equine fetlock.
Denoix, J M; Jacot, S; Bousseau, B; Perrot, P
1996-01-01
This paper describes normal ultrasound images of the soft tissues of the dorsal and abaxial aspects of the equine fetlock. The palmar aspect of the fetlock is not discussed because it is related to the suspensory apparatus and flexor tendon anatomy which has been previously described. Ultrasound scanning was performed with 7.5 MHz linear or 10 MHz sector probes and recorded on 7.5 cm U-matic videocassettes allowing further retrospective data analysis, computer manipulation and good image reproducibility. Sagittal, parasagittal, frontal and transverse ultrasound scans of 13 lameness free mature horses were compared to anatomically dissected leg specimens, anatomical sections and Magnetic Resonance Imaging scans of isolated limbs. The results are focused on the comparison between anatomical sections and ultrasonograms performed on the legs of nonlame horses. Ultrasonography was demonstrated to be a very accurate imaging procedure for soft tissue structures at the dorsal and abaxial aspects of the equine fetlock. Under clinical conditions, a thorough knowledge of normal ultrasonographic anatomy is critical for an accurate diagnosis of fetlock soft tissue injury.
Time-lapse microscopy and image processing for stem cell research: modeling cell migration
NASA Astrophysics Data System (ADS)
Gustavsson, Tomas; Althoff, Karin; Degerman, Johan; Olsson, Torsten; Thoreson, Ann-Catrin; Thorlin, Thorleif; Eriksson, Peter
2003-05-01
This paper presents hardware and software procedures for automated cell tracking and migration modeling. A time-lapse microscopy system equipped with a computer controllable motorized stage was developed. The performance of this stage was improved by incorporating software algorithms for stage motion displacement compensation and auto focus. The microscope is suitable for in-vitro stem cell studies and allows for multiple cell culture image sequence acquisition. This enables comparative studies concerning rate of cell splits, average cell motion velocity, cell motion as a function of cell sample density and many more. Several cell segmentation procedures are described as well as a cell tracking algorithm. Statistical methods for describing cell migration patterns are presented. In particular, the Hidden Markov Model (HMM) was investigated. Results indicate that if the cell motion can be described as a non-stationary stochastic process, then the HMM can adequately model aspects of its dynamic behavior.
BIM authoring for an image-based bridge maintenance system of existing cable-supported bridges
NASA Astrophysics Data System (ADS)
Dang, N. S.; Shim, C. S.
2018-04-01
Infrastructure nowadays is increasingly become the main backbone for the metropolitan development in general. Along with the rise of new facilities, the demand in term of maintenance for the existing bridges is indispensable. Recently, the terminology of “preventive maintenance” is not unfamiliar with the engineer, literally is the use of a bridge maintenance system (BMS) based on a BIM-oriented model. In this paper, the process of generating a BMS based on BIM model is introduced in detail. Data management for this BMS is separated into two modules: site inspection system and information management system. The noteworthy aspect of this model lays on the closed and automatic process of “capture image, generate the technical damage report, and upload/feedback to the BMS” in real-time. A pilot BMS system for a cable-supported bridge is presented which showed a good performance and potential to further development of preventive maintenance.
Computer vision system for egg volume prediction using backpropagation neural network
NASA Astrophysics Data System (ADS)
Siswantoro, J.; Hilman, M. Y.; Widiasri, M.
2017-11-01
Volume is one of considered aspects in egg sorting process. A rapid and accurate volume measurement method is needed to develop an egg sorting system. Computer vision system (CVS) provides a promising solution for volume measurement problem. Artificial neural network (ANN) has been used to predict the volume of egg in several CVSs. However, volume prediction from ANN could have less accuracy due to inappropriate input features or inappropriate ANN structure. This paper proposes a CVS for predicting the volume of egg using ANN. The CVS acquired an image of egg from top view and then processed the image to extract its 1D and 2 D size features. The features were used as input for ANN in predicting the volume of egg. The experiment results show that the proposed CSV can predict the volume of egg with a good accuracy and less computation time.
NASA Astrophysics Data System (ADS)
Wantuch, Andrew C.; Vita, Joshua A.; Jimenez, Edward S.; Bray, Iliana E.
2016-10-01
Despite object detection, recognition, and identification being very active areas of computer vision research, many of the available tools to aid in these processes are designed with only photographs in mind. Although some algorithms used specifically for feature detection and identification may not take explicit advantage of the colors available in the image, they still under-perform on radiographs, which are grayscale images. We are especially interested in the robustness of these algorithms, specifically their performance on a preexisting database of X-ray radiographs in compressed JPEG form, with multiple ways of describing pixel information. We will review various aspects of the performance of available feature detection and identification systems, including MATLABs Computer Vision toolbox, VLFeat, and OpenCV on our non-ideal database. In the process, we will explore possible reasons for the algorithms' lessened ability to detect and identify features from the X-ray radiographs.
NASA Astrophysics Data System (ADS)
Doughty, Benjamin; Simpson, Mary Jane; Yang, Bin; Xiao, Kai; Ma, Ying-Zhong
2016-03-01
This work aims to simplify multi-dimensional femtosecond transient absorption microscopy (TAM) data into decay associated amplitude maps (DAAMs) that describe the spatial distributions of dynamical processes occurring on various characteristic timescales. Application of this method to TAM data obtained from a model methyl-ammonium lead iodide (CH3NH3PbI3) perovskite thin film allows us to simplify the data set comprising 68 time-resolved images into four DAAMs. These maps offer a simple means to visualize the complex electronic excited-state dynamics in this system by separating distinct dynamical processes evolving on characteristic timescales into individual spatial images. This approach provides new insight into subtle aspects of ultrafast relaxation dynamics associated with excitons and charge carriers in the perovskite thin film, which have recently been found to coexist at spatially distinct locations.
[Language Functions in the Frontal Association Area: Brain Mechanisms That Create Language].
Yamamoto, Kayako; Sakai, Kuniyoshi L
2016-11-01
Broca's area is known to be critically involved in language processing for more than 150 years. Recent neuroimaging techniques, including functional magnetic resonance imaging (fMRI) and diffusion MRI, enabled the subdivision of Broca's area based on both functional and anatomical aspects. Networks among the frontal association areas, especially the left inferior frontal gyrus (IFG), and other cortical regions in the temporal/parietal association areas, are also important for language-related information processing. Here, we review how neuroimaging studies, combined with research paradigms based on theoretical linguistics, have contributed to clarifying the critical roles of the left IFG in syntactic processing and those of language-related networks, including cortical and cerebellar regions.
How does the brain process music?
Warren, Jason
2008-02-01
The organisation of the musical brain is a major focus of interest in contemporary neuroscience. This reflects the increasing sophistication of tools (especially imaging techniques) to examine brain anatomy and function in health and disease, and the recognition that music provides unique insights into a number of aspects of nonverbal brain function. The emerging picture is complex but coherent, and moves beyond older ideas of music as the province of a single brain area or hemisphere to the concept of music as a 'whole-brain' phenomenon. Music engages a distributed set of cortical modules that process different perceptual, cognitive and emotional components with varying selectivity. 'Why' rather than 'how' the brain processes music is a key challenge for the future.
Torres-Sánchez, Jorge; López-Granados, Francisca; De Castro, Ana Isabel; Peña-Barragán, José Manuel
2013-01-01
A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches).
Torres-Sánchez, Jorge; López-Granados, Francisca; De Castro, Ana Isabel; Peña-Barragán, José Manuel
2013-01-01
A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches). PMID:23483997
Ripp, Isabelle; Zur Nieden, Anna-Nora; Blankenagel, Sonja; Franzmeier, Nicolai; Lundström, Johan N; Freiherr, Jessica
2018-05-07
In this study, we aimed to understand how whole-brain neural networks compute sensory information integration based on the olfactory and visual system. Task-related functional magnetic resonance imaging (fMRI) data was obtained during unimodal and bimodal sensory stimulation. Based on the identification of multisensory integration processing (MIP) specific hub-like network nodes analyzed with network-based statistics using region-of-interest based connectivity matrices, we conclude the following brain areas to be important for processing the presented bimodal sensory information: right precuneus connected contralaterally to the supramarginal gyrus for memory-related imagery and phonology retrieval, and the left middle occipital gyrus connected ipsilaterally to the inferior frontal gyrus via the inferior fronto-occipital fasciculus including functional aspects of working memory. Applied graph theory for quantification of the resulting complex network topologies indicates a significantly increased global efficiency and clustering coefficient in networks including aspects of MIP reflecting a simultaneous better integration and segregation. Graph theoretical analysis of positive and negative network correlations allowing for inferences about excitatory and inhibitory network architectures revealed-not significant, but very consistent-that MIP-specific neural networks are dominated by inhibitory relationships between brain regions involved in stimulus processing. © 2018 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Muench, R.; Jones, M.; Herndon, K. E.; Bell, J. R.; Anderson, E. R.; Markert, K. N.; Molthan, A.; Adams, E. C.; Shultz, L.; Cherrington, E. A.; Flores, A.; Lucey, R.; Munroe, T.; Layne, G.; Pulla, S. T.; Weigel, A. M.; Tondapu, G.
2017-12-01
On August 25, 2017, Hurricane Harvey made landfall between Port Aransas and Port O'Connor, Texas, bringing with it unprecedented amounts of rainfall and flooding. In times of natural disasters of this nature, emergency responders require timely and accurate information about the hazard in order to assess and plan for disaster response. Due to the extreme flooding impacts associated with Hurricane Harvey, delineations of water extent were crucial to inform resource deployment. Through the USGS's Hazards Data Distribution System, government and commercial vendors were able to acquire and distribute various satellite imagery to analysts to create value-added products that can be used by these emergency responders. Rapid-response water extent maps were created through a collaborative multi-organization and multi-sensor approach. One team of researchers created Synthetic Aperture Radar (SAR) water extent maps using modified Copernicus Sentinel data (2017), processed by ESA. This group used backscatter images, pre-processed by the Alaska Satellite Facility's Hybrid Pluggable Processing Pipeline (HyP3), to identify and apply a threshold to identify water in the image. Quality control was conducted by manually examining the image and correcting for potential errors. Another group of researchers and graduate student volunteers derived water masks from high resolution DigitalGlobe and SPOT images. Through a system of standardized image processing, quality control measures, and communication channels the team provided timely and fairly accurate water extent maps to support a larger NASA Disasters Program response. The optical imagery was processed through a combination of various band thresholds by using Normalized Difference Water Index (NDWI), Modified Normalized Water Index (MNDWI), Normalized Difference Vegetation Index (NDVI), and cloud masking. Several aspects of the pre-processing and image access were run on internal servers to expedite the provision of images to analysts who could focus on manipulating thresholds and quality control checks for maximum accuracy within the time constraints. The combined results of the radar- and optical-derived value-added products through the coordination of multiple organizations provided timely information for emergency response and recovery efforts
NASA Technical Reports Server (NTRS)
Muench, Rebekke; Jones, Madeline; Herndon, Kelsey; Schultz, Lori; Bell, Jordan; Anderson, Eric; Markert, Kel; Molthan, Andrew; Adams, Emily; Cherrington, Emil;
2017-01-01
On August 25, 2017, Hurricane Harvey made landfall between Port Aransas and Port O'Connor, Texas, bringing with it unprecedented amounts of rainfall and record flooding. In times of natural disasters of this nature, emergency responders require timely and accurate information about the hazard in order to assess and plan for disaster response. Due to the extreme flooding impacts associated with Hurricane Harvey, delineations of water extent were crucial to inform resource deployment. Through the USGS's Hazards Data Distribution System, government and commercial vendors were able to acquire and distribute various satellite imagery to analysts to create value-added products that can be used by these emergency responders. Rapid-response water extent maps were created through a collaborative multi-organization and multi-sensor approach. One team of researchers created Synthetic Aperture Radar (SAR) water extent maps using modified Copernicus Sentinel data (2017), processed by ESA. This group used backscatter images, pre-processed by the Alaska Satellite Facility's Hybrid Pluggable Processing Pipeline (HyP3), to identify and apply a threshold to identify water in the image. Quality control was conducted by manually examining the image and correcting for potential errors. Another group of researchers and graduate student volunteers derived water masks from high resolution DigitalGlobe and SPOT images. Through a system of standardized image processing, quality control measures, and communication channels the team provided timely and fairly accurate water extent maps to support a larger NASA Disasters Program response. The optical imagery was processed through a combination of various band thresholds and by using Normalized Difference Water Index (NDWI), Modified Normalized Water Index (MNDWI), Normalized Difference Vegetation Index (NDVI), and cloud masking. Several aspects of the pre-processing and image access were run on internal servers to expedite the provision of images to analysts who could focus on manipulating thresholds and quality control checks for maximum accuracy within the time constraints. The combined results of the radar- and optical-derived value-added products through the coordination of multiple organizations provided timely information for emergency response and recovery efforts.
Fahed, Robert; Lecler, Augustin; Sabben, Candice; Khoury, Naim; Ducroux, Célina; Chalumeau, Vanessa; Botta, Daniele; Kalsoum, Erwah; Boisseau, William; Duron, Loïc; Cabral, Dominique; Koskas, Patricia; Benaïssa, Azzedine; Koulakian, Hasmik; Obadia, Michael; Maïer, Benjamin; Weisenburger-Lile, David; Lapergue, Bertrand; Wang, Adrien; Redjem, Hocine; Ciccio, Gabriele; Smajda, Stanislas; Desilles, Jean-Philippe; Mazighi, Mikaël; Ben Maacha, Malek; Akkari, Inès; Zuber, Kevin; Blanc, Raphaël; Raymond, Jean; Piotin, Michel
2018-01-01
We aimed to study the intrarater and interrater agreement of clinicians attributing DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) mismatch in patients with acute ischemic stroke referred for mechanical thrombectomy. Eighteen raters independently scored anonymized magnetic resonance imaging scans of 30 participants from a multicentre thrombectomy trial, in 2 different reading sessions. Agreement was measured using Fleiss κ and Cohen κ statistics. Interrater agreement for DWI-ASPECTS was slight (κ=0.17 [0.14-0.21]). Four raters (22.2%) had a substantial (or higher) intrarater agreement. Dichotomization of the DWI-ASPECTS (0-5 versus 6-10 or 0-6 versus 7-10) increased the interrater agreement to a substantial level (κ=0.62 [0.48-0.75] and 0.68 [0.55-0.79], respectively) and more raters reached a substantial (or higher) intrarater agreement (17/18 raters [94.4%]). Interrater agreement for DWI-FLAIR mismatch was moderate (κ=0.43 [0.33-0.57]); 11 raters (61.1%) reached a substantial (or higher) intrarater agreement. Agreement between clinicians assessing DWI-ASPECTS and DWI-FLAIR mismatch may not be sufficient to make repeatable clinical decisions in mechanical thrombectomy. The dichotomization of the DWI-ASPECTS (0-5 versus 0-6 or 0-6 versus 7-10) improved interrater and intrarater agreement, however, its relevance for patients selection for mechanical thrombectomy needs to be validated in a randomized trial. © 2017 American Heart Association, Inc.
Viruses, Artificial Viruses and Virus-Based Structures for Biomedical Applications.
van Rijn, Patrick; Schirhagl, Romana
2016-06-01
Nanobiomaterials such as virus particles and artificial virus particles offer tremendous opportunities to develop new biomedical applications such as drug- or gene-delivery, imaging and sensing but also improve understanding of biological mechanisms. Recent advances within the field of virus-based systems give insights in how to mimic viral structures and virus assembly processes as well as understanding biodistribution, cell/tissue targeting, controlled and triggered disassembly or release and circulation times. All these factors are of high importance for virus-based functional systems. This review illustrates advances in mimicking and enhancing or controlling these aspects to a high degree toward delivery and imaging applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
All-optical video-image encryption with enforced security level using independent component analysis
NASA Astrophysics Data System (ADS)
Alfalou, A.; Mansour, A.
2007-10-01
In the last two decades, wireless communications have been introduced in various applications. However, the transmitted data can be, at any moment, intercepted by non-authorized people. That could explain why data encryption and secure transmission have gained enormous popularity. In order to secure data transmission, we should pay attention to two aspects: transmission rate and encryption security level. In this paper, we address these two aspects by proposing a new video-image transmission scheme. This new system consists in using the advantage of optical high transmission rate and some powerful signal processing tools to secure the transmitted data. The main idea of our approach is to secure transmitted information at two levels: at the classical level by using an adaptation of standard optical techniques and at a second level (spatial diversity) by using independent transmitters. In the second level, a hacker would need to intercept not only one channel but all of them in order to retrieve information. At the receiver, we can easily apply ICA algorithms to decrypt the received signals and retrieve information.
Focusing Solar Hard X-rays: Expected Results from a FOXSI Spacecraft
NASA Astrophysics Data System (ADS)
Glesener, L.; Christe, S.; Shih, A. Y.; Dennis, B. R.; Krucker, S.; Saint-Hilaire, P.; Hudson, H. S.; Ryan, D.; Inglis, A. R.; Hannah, I. G.; Caspi, A.; Klimchuk, J. A.; Drake, J. F.; Kontar, E.; Holman, G.; White, S. M.; Alaoui, M.; Battaglia, M.; Vilmer, N.; Allred, J. C.; Longcope, D. W.; Gary, D. E.; Jeffrey, N. L. S.; Musset, S.; Swisdak, M.
2016-12-01
Over the course of two solar cycles, RHESSI has examined high-energy processes in flares via high-resolution spectroscopy and imaging of soft and hard X-rays (HXRs). The detected X-rays are the thermal and nonthermal bremsstrahlung from heated coronal plasma and from accelerated electrons, respectively, making them uniquely suited to explore the highest-energy processes that occur in the corona. RHESSI produces images using an indirect, Fourier-based method and has made giant strides in our understanding of these processes, but it has also uncovered intriguing new mysteries regarding energy release location, acceleration mechanisms, and energy propagation in flares. Focusing optics are now available for the HXR regime and stand poised to perform another revolution in the field of high-energy solar physics. With two successful sounding rocket flights completed, the Focusing Optics X-ray Solar Imager (FOXSI) program has demonstrated the feasibility and power of direct solar HXR imaging with its vastly superior sensitivity and dynamic range. Placing this mature technology aboard a spacecraft will offer a systematic way to explore high-energy aspects of the solar corona and to address scientific questions left unanswered by RHESSI. Here we present examples of such questions and show simulations of expected results from a FOXSI spaceborne instrument to demonstrate how these questions can be addressed with the focusing of hard X-rays.
DISTA: a portable software solution for 3D compilation of photogrammetric image blocks
NASA Astrophysics Data System (ADS)
Boochs, Frank; Mueller, Hartmut; Neifer, Markus
2001-04-01
A photogrammetric evaluation system used for the precise determination of 3D-coordinates from blocks of large metric images will be presented. First, the motivation for the development is shown, which is placed in the field of processing tools for photogrammetric evaluation tasks. As the use and availability of metric images of digital type rapidly increases corresponding equipment for the measuring process is needed. Systems which have been developed up to now are either very special ones, founded on high end graphics workstations with an according pricing or simple ones with restricted measuring functionality. A new conception will be shown, avoiding special high end graphics hardware but providing a complete processing chain for all elementary photogrammetric tasks ranging from preparatory steps over the formation of image blocks up to the automatic and interactive 3D-evaluation within digital stereo models. The presented system is based on PC-hardware equipped with off the shelf graphics boards and uses an object oriented design. The specific needs of a flexible measuring system and the corresponding requirements which have to be met by the system are shown. Important aspects as modularity and hardware independence and their value for the solution are shown. The design of the software will be presented and first results with a prototype realised on a powerful PC-hardware configuration will be featured
NASA Technical Reports Server (NTRS)
Cardullo, Frank M.; Lewis, Harold W., III; Panfilov, Peter B.
2007-01-01
An extremely innovative approach has been presented, which is to have the surgeon operate through a simulator running in real-time enhanced with an intelligent controller component to enhance the safety and efficiency of a remotely conducted operation. The use of a simulator enables the surgeon to operate in a virtual environment free from the impediments of telecommunication delay. The simulator functions as a predictor and periodically the simulator state is corrected with truth data. Three major research areas must be explored in order to ensure achieving the objectives. They are: simulator as predictor, image processing, and intelligent control. Each is equally necessary for success of the project and each of these involves a significant intelligent component in it. These are diverse, interdisciplinary areas of investigation, thereby requiring a highly coordinated effort by all the members of our team, to ensure an integrated system. The following is a brief discussion of those areas. Simulator as a predictor: The delays encountered in remote robotic surgery will be greater than any encountered in human-machine systems analysis, with the possible exception of remote operations in space. Therefore, novel compensation techniques will be developed. Included will be the development of the real-time simulator, which is at the heart of our approach. The simulator will present real-time, stereoscopic images and artificial haptic stimuli to the surgeon. Image processing: Because of the delay and the possibility of insufficient bandwidth a high level of novel image processing is necessary. This image processing will include several innovative aspects, including image interpretation, video to graphical conversion, texture extraction, geometric processing, image compression and image generation at the surgeon station. Intelligent control: Since the approach we propose is in a sense predictor based, albeit a very sophisticated predictor, a controller, which not only optimizes end effector trajectory but also avoids error, is essential. We propose to investigate two different approaches to the controller design. One approach employs an optimal controller based on modern control theory; the other one involves soft computing techniques, i.e. fuzzy logic, neural networks, genetic algorithms and hybrids of these.
Price, P M; Green, M M
2011-01-01
In an era in which it is possible to deliver radiation with high precision, there is a heightened need for enhanced imaging capabilities to improve tumour localisation for diagnostic, planning and delivery purposes. This is necessary to increase the accuracy and overall efficacy of all types of external beam radiotherapy (RT), including particle therapies. Positron emission tomography (PET) has the potential to fulfil this need by imaging fundamental aspects of tumour biology. The key areas in which PET may support the RT process include improving disease diagnosis and staging; assisting tumour volume delineation; defining tumour phenotype or biological tumour volume; assessment of treatment response; and in-beam monitoring of radiation dosimetry. The role of PET and its current developmental status in these key areas are overviewed in this review, highlighting the advantages and drawbacks. PMID:21427180
Optical Spectroscopy and Imaging for the Noninvasive Evaluation of Engineered Tissues
Rice, William L.; Hronik-Tupaj, Marie; Kaplan, David L.
2008-01-01
Optical spectroscopy and imaging approaches offer the potential to noninvasively assess different aspects of the cellular, extracellular matrix, and scaffold components of engineered tissues. In addition, the combination of multiple imaging modalities within a single instrument is highly feasible, allowing acquisition of complementary information related to the structure, organization, biochemistry, and physiology of the sample. The ability to characterize and monitor the dynamic interactions that take place as engineered tissues develop promises to enhance our understanding of the interdependence of processes that ultimately leads to functional tissue outcomes. It is expected that this information will impact significantly upon our abilities to optimize the design of biomaterial scaffolds, bioreactors, and cell systems. Here, we review the principles and performance characteristics of the main methodologies that have been exploited thus far, and we present examples of corresponding tissue engineering studies. PMID:18844604
Photogrammetry on glaciers: Old and new knowledge
NASA Astrophysics Data System (ADS)
Pfeffer, W. T.; Welty, E.; O'Neel, S.
2014-12-01
In the past few decades terrestrial photogrammetry has become a widely used tool for glaciological research, brought about in part by the proliferation of high-quality, low-cost digital cameras, dramatic increases in image-processing power of computers, and very innovative progress in image processing, much of which has come from computer vision research and from the computer gaming industry. At present, glaciologists have developed their capacity to gather images much further than their ability to process them. Many researchers have accumulated vast inventories of imagery, but have no efficient means to extract the data they desire from them. In many cases these are single-image time series where the processing limitation lies in the paucity of methods to obtain 3-dimension object space information from measurements in the 2-dimensional image space; in other cases camera pairs have been operated but no automated means is in hand for conventional stereometric analysis of many thousands of image pairs. Often the processing task is further complicated by weak camera geometry or ground control distribution, either of which will compromise the quality of 3-dimensional object space solutions. Solutions exist for many of these problems, found sometimes among the latest computer vision results, and sometimes buried in decades-old pre-digital terrestrial photogrammetric literature. Other problems, particularly those arising from poorly constrained or underdetermined camera and ground control geometry, may be unsolvable. Small-scale, ground-based photography and photogrammetry of glaciers has grown over the past few decades in an organic and disorganized fashion, with much duplication of effort and little coordination or sharing of knowledge among researchers. Given the utility of terrestrial photogrammetry, its low cost (if properly developed and implemented), and the substantial value of the information to be had from it, some further effort to share knowledge and methods would be a great benefit for the community. We consider some of the main problems to be solved, and aspects of how optimal knowledge sharing might be accomplished.
Speckle imaging of active galactic nuclei: NGC 1068 and NGC 4151
NASA Astrophysics Data System (ADS)
Ebstein, Steven Michael
High resolution images of NGC 1068 and NGC 4151 in the 5007 A line and the nearby continuum produced from data taken with the PAPA photon counting imaging detector using the technique of speckle imaging are presented. The images show an unresolved core of 5007 A emission in the middle of an extended emission region. The extended emission tends to lie alongside the subarcsecond radio structure. In NGC 4151, the extended emission comes from a nearly linear structure extending on both sides of the unresolved core. In NGC 1068, the extended emission is concentrated in lobes lying to the unresolved core but the emission is concentrated in lobes lying to either side of the major axis. The continuum of NGC 4151 is spatially unresolved. The continuum of NGC 1068 is extended approx. 1 in to the SW of the center of the 5007 A emission. Certain aspects of the PAPA detector are discussed, including the variable threshold discriminators that track the image intensifier pulse height and the camera artifacts. The data processing is described in detail.
Remote Sensing of Landscapes with Spectral Images
NASA Astrophysics Data System (ADS)
Adams, John B.; Gillespie, Alan R.
2006-05-01
Remote Sensing of Landscapes with Spectral Images describes how to process and interpret spectral images using physical models to bridge the gap between the engineering and theoretical sides of remote-sensing and the world that we encounter when we venture outdoors. The emphasis is on the practical use of images rather than on theory and mathematical derivations. Examples are drawn from a variety of landscapes and interpretations are tested against the reality seen on the ground. The reader is led through analysis of real images (using figures and explanations); the examples are chosen to illustrate important aspects of the analytic framework. This textbook will form a valuable reference for graduate students and professionals in a variety of disciplines including ecology, forestry, geology, geography, urban planning, archeology and civil engineering. It is supplemented by a web-site hosting digital color versions of figures in the book as well as ancillary images (www.cambridge.org/9780521662214). Presents a coherent view of practical remote sensing, leading from imaging and field work to the generation of useful thematic maps Explains how to apply physical models to help interpret spectral images Supplemented by a website hosting digital colour versions of figures in the book, as well as additional colour figures
Imaging characteristics of photogrammetric camera systems
Welch, R.; Halliday, J.
1973-01-01
In view of the current interest in high-altitude and space photographic systems for photogrammetric mapping, the United States Geological Survey (U.S.G.S.) undertook a comprehensive research project designed to explore the practical aspects of applying the latest image quality evaluation techniques to the analysis of such systems. The project had two direct objectives: (1) to evaluate the imaging characteristics of current U.S.G.S. photogrammetric camera systems; and (2) to develop methodologies for predicting the imaging capabilities of photogrammetric camera systems, comparing conventional systems with new or different types of systems, and analyzing the image quality of photographs. Image quality was judged in terms of a number of evaluation factors including response functions, resolving power, and the detectability and measurability of small detail. The limiting capabilities of the U.S.G.S. 6-inch and 12-inch focal length camera systems were established by analyzing laboratory and aerial photographs in terms of these evaluation factors. In the process, the contributing effects of relevant parameters such as lens aberrations, lens aperture, shutter function, image motion, film type, and target contrast procedures for analyzing image quality and predicting and comparing performance capabilities. ?? 1973.
Modeling Of Object- And Scene-Prototypes With Hierarchically Structured Classes
NASA Astrophysics Data System (ADS)
Ren, Z.; Jensch, P.; Ameling, W.
1989-03-01
The success of knowledge-based image analysis methodology and implementation tools depends largely on an appropriately and efficiently built model wherein the domain-specific context information about and the inherent structure of the observed image scene have been encoded. For identifying an object in an application environment a computer vision system needs to know firstly the description of the object to be found in an image or in an image sequence, secondly the corresponding relationships between object descriptions within the image sequence. This paper presents models of image objects scenes by means of hierarchically structured classes. Using the topovisual formalism of graph and higraph, we are currently studying principally the relational aspect and data abstraction of the modeling in order to visualize the structural nature resident in image objects and scenes, and to formalize. their descriptions. The goal is to expose the structure of image scene and the correspondence of image objects in the low level image interpretation. process. The object-based system design approach has been applied to build the model base. We utilize the object-oriented programming language C + + for designing, testing and implementing the abstracted entity classes and the operation structures which have been modeled topovisually. The reference images used for modeling prototypes of objects and scenes are from industrial environments as'well as medical applications.
A method for smoothing segmented lung boundary in chest CT images
NASA Astrophysics Data System (ADS)
Yim, Yeny; Hong, Helen
2007-03-01
To segment low density lung regions in chest CT images, most of methods use the difference in gray-level value of pixels. However, radiodense pulmonary vessels and pleural nodules that contact with the surrounding anatomy are often excluded from the segmentation result. To smooth lung boundary segmented by gray-level processing in chest CT images, we propose a new method using scan line search. Our method consists of three main steps. First, lung boundary is extracted by our automatic segmentation method. Second, segmented lung contour is smoothed in each axial CT slice. We propose a scan line search to track the points on lung contour and find rapidly changing curvature efficiently. Finally, to provide consistent appearance between lung contours in adjacent axial slices, 2D closing in coronal plane is applied within pre-defined subvolume. Our method has been applied for performance evaluation with the aspects of visual inspection, accuracy and processing time. The results of our method show that the smoothness of lung contour was considerably increased by compensating for pulmonary vessels and pleural nodules.
Unified modeling language and design of a case-based retrieval system in medical imaging.
LeBozec, C; Jaulent, M C; Zapletal, E; Degoulet, P
1998-01-01
One goal of artificial intelligence research into case-based reasoning (CBR) systems is to develop approaches for designing useful and practical interactive case-based environments. Explaining each step of the design of the case-base and of the retrieval process is critical for the application of case-based systems to the real world. We describe herein our approach to the design of IDEM--Images and Diagnosis from Examples in Medicine--a medical image case-based retrieval system for pathologists. Our approach is based on the expressiveness of an object-oriented modeling language standard: the Unified Modeling Language (UML). We created a set of diagrams in UML notation illustrating the steps of the CBR methodology we used. The key aspect of this approach was selecting the relevant objects of the system according to user requirements and making visualization of cases and of the components of the case retrieval process. Further evaluation of the expressiveness of the design document is required but UML seems to be a promising formalism, improving the communication between the developers and users.
NASA Astrophysics Data System (ADS)
Hurford, Gordon J.; Krucker, Samuel
The previous solar maximum has featured high resolution imaging/spectroscopy observations at hard x-ray and gamma-ray energies by the Reuven Ramaty High Energy Solar/Spectroscopic Imager (RHESSI). Highlights of these observations will be reviewed, along with their impli-cations for our understanding of ion and electron acceleration and transport processes. The results to date have included new insights into the location of the acceleration region and the thick target model, a new appreciation of the significance of x-ray albedo, observation of coronal gamma-ray sources and their implications for electron trapping, and indications of differences in the acceleration and transport between electrons and ions. The role of RHESSI's observational strengths and weaknesses in determining the character of its scientific results will also be discussed and used to identify what aspects of the acceleration and transport processes must await the next generation of instrumentation. The extent to which new instrumentation now under development, such as Solar Orbiter/STIX, GRIPS, and FOXSI, can address these open issues will be outlined.
Shon, Hyun-Chul; Park, Ji-Kang; Kim, Dong-Soo; Kang, Sang-Woo; Kim, Kook-Jong; Hong, Seok-Hyun
2018-01-01
The supracondylar process is a beak-shaped bony process on the anteromedial aspect of the distal humerus. The ligament of Struthers is a fibrous band extending from the tip of the process to the medial epicondyle. The median nerve and brachial artery pass under the ligament of Struthers and consequently can be compressed, causing supracondylar process syndrome. As a rare cause of proximal median nerve entrapment, supracondylar process syndrome is triggered when the median nerve is located in the superficial or deep layer of the ligament of Struthers as a result of anatomical variation. The supracondylar process can be easily detected on X-ray images obtained in oblique views but may not be identified in only anteroposterior or lateral views. In this article, we present 2 cases of supracondylar process syndrome and describe the process of diagnosis and treatment and results of a literature review.
Vu, Cung; Nihei, Kurt T.; Schmitt, Denis P.; Skelt, Christopher; Johnson, Paul A.; Guyer, Robert; TenCate, James A.; Le Bas, Pierre-Yves
2013-01-01
In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region remote from a borehole using a conveyed logging tool is disclosed. In some aspects, the method includes arranging a first source in the borehole and generating a steered beam of elastic energy at a first frequency; arranging a second source in the borehole and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location away from the borehole; receiving at the borehole by a sensor a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole; determining a location of a three wave mixing region based on the arrangement of the first and second sources and on properties of the third wave signal; and creating three-dimensional images of the non-linear properties using data recorded by repeating the generating, receiving and determining at a plurality of azimuths, inclinations and longitudinal locations within the borehole. The method is additionally used to generate three dimensional images of the ratio of compressional to shear acoustic velocity of the same volume surrounding the borehole.
Application of separable parameter space techniques to multi-tracer PET compartment modeling
Zhang, Jeff L; Morey, A Michael; Kadrmas, Dan J
2016-01-01
Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg–Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models. PMID:26788888
Lechuga, Lawrence; Weidlich, Georg A
2016-09-12
A comparison of image quality and dose delivered between two differing computed tomography (CT) imaging modalities-fan beam and cone beam-was performed. A literature review of quantitative analyses for various image quality aspects such as uniformity, signal-to-noise ratio, artifact presence, spatial resolution, modulation transfer function (MTF), and low contrast resolution was generated. With these aspects quantified, cone beam computed tomography (CBCT) shows a superior spatial resolution to that of fan beam, while fan beam shows a greater ability to produce clear and anatomically correct images with better soft tissue differentiation. The results indicate that fan beam CT produces superior images to that of on-board imaging (OBI) cone beam CT systems, while providing a considerably less dose to the patient.
Weidlich, Georg A.
2016-01-01
A comparison of image quality and dose delivered between two differing computed tomography (CT) imaging modalities—fan beam and cone beam—was performed. A literature review of quantitative analyses for various image quality aspects such as uniformity, signal-to-noise ratio, artifact presence, spatial resolution, modulation transfer function (MTF), and low contrast resolution was generated. With these aspects quantified, cone beam computed tomography (CBCT) shows a superior spatial resolution to that of fan beam, while fan beam shows a greater ability to produce clear and anatomically correct images with better soft tissue differentiation. The results indicate that fan beam CT produces superior images to that of on-board imaging (OBI) cone beam CT systems, while providing a considerably less dose to the patient. PMID:27752404
NASA Astrophysics Data System (ADS)
Lyu, F.; Cummer, S. A.; Weinert, J. L.; McTague, L. E.; Solanki, R.; Barrett, J.
2014-12-01
Lightning processes radiated extremely wideband electromagnetic signals. Lightning images mapped by VHF interferometry and VHF time of arrival lightning mapping arrays enable us to understand the lightning in-cloud detail development during the extent of flash that can not always be captured by cameras because of the shield of cloud. Lightning processes radiate electromagnetically over an extremely wide bandwidth, offering the possibility of multispectral lightning radio imaging. Low frequency signals are often used for lightning detection, but usually only for ground point location or thunderstorm tracking. Some recent results have demonstrated lightning LF 3D mapping of discrete lightning pulses, but imaging of continuous LF emissions have not been shown. In this work, we report a GPS-synchronized LF near field interferometric-TOA 3D lightning mapping array applied to image the development of lightning flashes on second time scale. Cross-correlation, as used in broadband interferometry, is applied in our system to find windowed arrival time differences with sub-microsecond time resolution. However, because the sources are in the near field of the array, time of arrival processing is used to find the source locations with a typical precision of 100 meters. We show that this system images the complete lightning flash structure with thousands of LF sources for extensive flashes. Importantly, this system is able to map both continuous emissions like dart leaders, and bursty or discrete emissions. Lightning stepped leader and dart leader propagation speeds are estimated to 0.56-2.5x105 m/s and 0.8-2.0x106 m/s respectively, which are consistent with previous reports. In many aspects our LF images are remarkably similar to VHF lightning mapping array images, despite the 1000 times difference in frequency, which may suggest some special links between the LF and VHF emission during lightning processes.
Fongaro, Lorenzo; Alamprese, Cristina; Casiraghi, Ernestina
2015-03-01
During ripening of salami, colour changes occur due to oxidation phenomena involving myoglobin. Moreover, shrinkage due to dehydration results in aspect modifications, mainly ascribable to fat aggregation. The aim of this work was the application of image analysis (IA) and multivariate image analysis (MIA) techniques to the study of colour and aspect changes occurring in salami during ripening. IA results showed that red, green, blue, and intensity parameters decreased due to the development of a global darker colour, while Heterogeneity increased due to fat aggregation. By applying MIA, different salami slice areas corresponding to fat and three different degrees of oxidised meat were identified and quantified. It was thus possible to study the trend of these different areas as a function of ripening, making objective an evaluation usually performed by subjective visual inspection. Copyright © 2014 Elsevier Ltd. All rights reserved.
Using the World Wide Web for GIDEP Problem Data Processing at Marshall Space Flight Center
NASA Technical Reports Server (NTRS)
McPherson, John W.; Haraway, Sandra W.; Whirley, J. Don
1999-01-01
Since April 1997, Marshall Space Flight Center has been using electronic transfer and the web to support our processing of the Government-Industry Data Exchange Program (GIDEP) and NASA ALERT information. Specific aspects include: (1) Extraction of ASCII text information from GIDEP for loading into Word documents for e-mail to ALERT actionees; (2) Downloading of GIDEP form image formats in Adobe Acrobat (.pdf) for internal storage display on the MSFC ALERT web page; (3) Linkage of stored GRDEP problem forms with summary information for access from the MSFC ALERT Distribution Summary Chart or from an html table of released MSFC ALERTs (4) Archival of historic ALERTs for reference by GIDEP ID, MSFC ID, or MSFC release date; (5) On-line tracking of ALERT response status using a Microsoft Access database and the web (6) On-line response to ALERTs from MSFC actionees through interactive web forms. The technique, benefits, effort, coordination, and lessons learned for each aspect are covered herein.
Visual Processing in Rapid-Chase Systems: Image Processing, Attention, and Awareness
Schmidt, Thomas; Haberkamp, Anke; Veltkamp, G. Marina; Weber, Andreas; Seydell-Greenwald, Anna; Schmidt, Filipp
2011-01-01
Visual stimuli can be classified so rapidly that their analysis may be based on a single sweep of feedforward processing through the visuomotor system. Behavioral criteria for feedforward processing can be evaluated in response priming tasks where speeded pointing or keypress responses are performed toward target stimuli which are preceded by prime stimuli. We apply this method to several classes of complex stimuli. (1) When participants classify natural images into animals or non-animals, the time course of their pointing responses indicates that prime and target signals remain strictly sequential throughout all processing stages, meeting stringent behavioral criteria for feedforward processing (rapid-chase criteria). (2) Such priming effects are boosted by selective visual attention for positions, shapes, and colors, in a way consistent with bottom-up enhancement of visuomotor processing, even when primes cannot be consciously identified. (3) Speeded processing of phobic images is observed in participants specifically fearful of spiders or snakes, suggesting enhancement of feedforward processing by long-term perceptual learning. (4) When the perceived brightness of primes in complex displays is altered by means of illumination or transparency illusions, priming effects in speeded keypress responses can systematically contradict subjective brightness judgments, such that one prime appears brighter than the other but activates motor responses as if it was darker. We propose that response priming captures the output of the first feedforward pass of visual signals through the visuomotor system, and that this output lacks some characteristic features of more elaborate, recurrent processing. This way, visuomotor measures may become dissociated from several aspects of conscious vision. We argue that “fast” visuomotor measures predominantly driven by feedforward processing should supplement “slow” psychophysical measures predominantly based on visual awareness. PMID:21811484
Different Images of Science at Nordic Science Centres
ERIC Educational Resources Information Center
Davidsson, Eva; Jakobsson, Anders
2007-01-01
Science centres aim to present science in ways that will attract visitors and enhance public interest in, and knowledge of, science. But what images and different aspects of science are visitors confronted with at Nordic science centres? This study aims to explore the different aspects of science that are displayed and the ways in which these…
Sadness is unique: neural processing of emotions in speech prosody in musicians and non-musicians
Park, Mona; Gutyrchik, Evgeny; Welker, Lorenz; Carl, Petra; Pöppel, Ernst; Zaytseva, Yuliya; Meindl, Thomas; Blautzik, Janusch; Reiser, Maximilian; Bao, Yan
2015-01-01
Musical training has been shown to have positive effects on several aspects of speech processing, however, the effects of musical training on the neural processing of speech prosody conveying distinct emotions are yet to be better understood. We used functional magnetic resonance imaging (fMRI) to investigate whether the neural responses to speech prosody conveying happiness, sadness, and fear differ between musicians and non-musicians. Differences in processing of emotional speech prosody between the two groups were only observed when sadness was expressed. Musicians showed increased activation in the middle frontal gyrus, the anterior medial prefrontal cortex, the posterior cingulate cortex and the retrosplenial cortex. Our results suggest an increased sensitivity of emotional processing in musicians with respect to sadness expressed in speech, possibly reflecting empathic processes. PMID:25688196
Anatomic modeling using 3D printing: quality assurance and optimization.
Leng, Shuai; McGee, Kiaran; Morris, Jonathan; Alexander, Amy; Kuhlmann, Joel; Vrieze, Thomas; McCollough, Cynthia H; Matsumoto, Jane
2017-01-01
The purpose of this study is to provide a framework for the development of a quality assurance (QA) program for use in medical 3D printing applications. An interdisciplinary QA team was built with expertise from all aspects of 3D printing. A systematic QA approach was established to assess the accuracy and precision of each step during the 3D printing process, including: image data acquisition, segmentation and processing, and 3D printing and cleaning. Validation of printed models was performed by qualitative inspection and quantitative measurement. The latter was achieved by scanning the printed model with a high resolution CT scanner to obtain images of the printed model, which were registered to the original patient images and the distance between them was calculated on a point-by-point basis. A phantom-based QA process, with two QA phantoms, was also developed. The phantoms went through the same 3D printing process as that of the patient models to generate printed QA models. Physical measurement, fit tests, and image based measurements were performed to compare the printed 3D model to the original QA phantom, with its known size and shape, providing an end-to-end assessment of errors involved in the complete 3D printing process. Measured differences between the printed model and the original QA phantom ranged from -0.32 mm to 0.13 mm for the line pair pattern. For a radial-ulna patient model, the mean distance between the original data set and the scanned printed model was -0.12 mm (ranging from -0.57 to 0.34 mm), with a standard deviation of 0.17 mm. A comprehensive QA process from image acquisition to completed model has been developed. Such a program is essential to ensure the required accuracy of 3D printed models for medical applications.
Social computing for image matching
Rivas, Alberto; Sánchez-Torres, Ramiro; Rodríguez, Sara
2018-01-01
One of the main technological trends in the last five years is mass data analysis. This trend is due in part to the emergence of concepts such as social networks, which generate a large volume of data that can provide added value through their analysis. This article is focused on a business and employment-oriented social network. More specifically, it focuses on the analysis of information provided by different users in image form. The images are analyzed to detect whether other existing users have posted or talked about the same image, even if the image has undergone some type of modification such as watermarks or color filters. This makes it possible to establish new connections among unknown users by detecting what they are posting or whether they are talking about the same images. The proposed solution consists of an image matching algorithm, which is based on the rapid calculation and comparison of hashes. However, there is a computationally expensive aspect in charge of revoking possible image transformations. As a result, the image matching process is supported by a distributed forecasting system that enables or disables nodes to serve all the possible requests. The proposed system has shown promising results for matching modified images, especially when compared with other existing systems. PMID:29813082
Caldas, Victor E A; Punter, Christiaan M; Ghodke, Harshad; Robinson, Andrew; van Oijen, Antoine M
2015-10-01
Recent technical advances have made it possible to visualize single molecules inside live cells. Microscopes with single-molecule sensitivity enable the imaging of low-abundance proteins, allowing for a quantitative characterization of molecular properties. Such data sets contain information on a wide spectrum of important molecular properties, with different aspects highlighted in different imaging strategies. The time-lapsed acquisition of images provides information on protein dynamics over long time scales, giving insight into expression dynamics and localization properties. Rapid burst imaging reveals properties of individual molecules in real-time, informing on their diffusion characteristics, binding dynamics and stoichiometries within complexes. This richness of information, however, adds significant complexity to analysis protocols. In general, large datasets of images must be collected and processed in order to produce statistically robust results and identify rare events. More importantly, as live-cell single-molecule measurements remain on the cutting edge of imaging, few protocols for analysis have been established and thus analysis strategies often need to be explored for each individual scenario. Existing analysis packages are geared towards either single-cell imaging data or in vitro single-molecule data and typically operate with highly specific algorithms developed for particular situations. Our tool, iSBatch, instead allows users to exploit the inherent flexibility of the popular open-source package ImageJ, providing a hierarchical framework in which existing plugins or custom macros may be executed over entire datasets or portions thereof. This strategy affords users freedom to explore new analysis protocols within large imaging datasets, while maintaining hierarchical relationships between experiments, samples, fields of view, cells, and individual molecules.
Herweh, Christian; Ringleb, Peter A; Rauch, Geraldine; Gerry, Steven; Behrens, Lars; Möhlenbruch, Markus; Gottorf, Rebecca; Richter, Daniel; Schieber, Simon; Nagel, Simon
2016-06-01
The Alberta Stroke Program Early CT score (ASPECTS) is an established 10-point quantitative topographic computed tomography scan score to assess early ischemic changes. We compared the performance of the e-ASPECTS software with those of stroke physicians at different professional levels. The baseline computed tomography scans of acute stroke patients, in whom computed tomography and diffusion-weighted imaging scans were obtained less than two hours apart, were retrospectively scored by e-ASPECTS as well as by three stroke experts and three neurology trainees blinded to any clinical information. The ground truth was defined as the ASPECTS on diffusion-weighted imaging scored by another two non-blinded independent experts on consensus basis. Sensitivity and specificity in an ASPECTS region-based and an ASPECTS score-based analysis as well as receiver-operating characteristic curves, Bland-Altman plots with mean score error, and Matthews correlation coefficients were calculated. Comparisons were made between the human scorers and e-ASPECTS with diffusion-weighted imaging being the ground truth. Two methods for clustered data were used to estimate sensitivity and specificity in the region-based analysis. In total, 34 patients were included and 680 (34 × 20) ASPECTS regions were scored. Mean time from onset to computed tomography was 172 ± 135 min and mean time difference between computed tomographyand magnetic resonance imaging was 41 ± 31 min. The region-based sensitivity (46.46% [CI: 30.8;62.1]) of e-ASPECTS was better than three trainees and one expert (p ≤ 0.01) and not statistically different from another two experts. Specificity (94.15% [CI: 91.7;96.6]) was lower than one expert and one trainee (p < 0.01) and not statistically different to the other four physicians. e-ASPECTS had the best Matthews correlation coefficient of 0.44 (experts: 0.38 ± 0.08 and trainees: 0.19 ± 0.05) and the lowest mean score error of 0.56 (experts: 1.44 ± 1.79 and trainees: 1.97 ± 2.12). e-ASPECTS showed a similar performance to that of stroke experts in the assessment of brain computed tomographys of acute ischemic stroke patients with the Alberta Stroke Program Early CT score method. © 2016 World Stroke Organization.
Different Aspects of the Monotonicity of a Function
ERIC Educational Resources Information Center
Tossavainen, Timo; Haukkanen, Pentti; Pesonen, Martti
2013-01-01
In this paper, we investigate which aspects are overriding in the concept images of monotonicity of Finnish tertiary mathematics students, i.e., on which aspects of monotonicity they base their argument in different types of exercises related to that concept. Further, we examine the relationship between the quality of principal aspects and the…
Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel
Collette, R.; Douglas, J.; Patterson, L.; ...
2015-05-01
Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellularmore » measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.« less
Do photographic images of pain improve communication during pain consultations?
Padfield, Deborah; Zakrzewska, Joanna M; Williams, Amanda C de C
2015-01-01
Visual images may facilitate the communication of pain during consultations. To assess whether photographic images of pain enrich the content and⁄or process of pain consultation by comparing patients' and clinicians' ratings of the consultation experience. Photographic images of pain previously co-created by patients with a photographer were provided to new patients attending pain clinic consultations. Seventeen patients selected and used images that best expressed their pain and were compared with 21 patients who were not shown images. Ten clinicians conducted assessments in each condition. After consultation, patients and clinicians completed ratings of aspects of communication and, when images were used, how they influenced the consultation. The majority of both patients and clinicians reported that images enhanced the consultation. Ratings of communication were generally high, with no differences between those with and without images (with the exception of confidence in treatment plan, which was rated more highly in the image group). However, patients' and clinicians' ratings of communication were inversely related only in consultations with images. Methodological shortcomings may underlie the present findings of no difference. It is also possible that using images raised patients' and clinicians' expectations and encouraged emotional disclosure, in response to which clinicians were dissatisfied with their performance. Using images in clinical encounters did not have a negative impact on the consultation, nor did it improve communication or satisfaction. These findings will inform future analysis of behaviour in the video-recorded consultations.
Improved Process for Fabricating Carbon Nanotube Probes
NASA Technical Reports Server (NTRS)
Stevens, R.; Nguyen, C.; Cassell, A.; Delzeit, L.; Meyyappan, M.; Han, Jie
2003-01-01
An improved process has been developed for the efficient fabrication of carbon nanotube probes for use in atomic-force microscopes (AFMs) and nanomanipulators. Relative to prior nanotube tip production processes, this process offers advantages in alignment of the nanotube on the cantilever and stability of the nanotube's attachment. A procedure has also been developed at Ames that effectively sharpens the multiwalled nanotube, which improves the resolution of the multiwalled nanotube probes and, combined with the greater stability of multiwalled nanotube probes, increases the effective resolution of these probes, making them comparable in resolution to single-walled carbon nanotube probes. The robust attachment derived from this improved fabrication method and the natural strength and resiliency of the nanotube itself produces an AFM probe with an extremely long imaging lifetime. In a longevity test, a nanotube tip imaged a silicon nitride surface for 15 hours without measurable loss of resolution. In contrast, the resolution of conventional silicon probes noticeably begins to degrade within minutes. These carbon nanotube probes have many possible applications in the semiconductor industry, particularly as devices are approaching the nanometer scale and new atomic layer deposition techniques necessitate a higher resolution characterization technique. Previously at Ames, the use of nanotube probes has been demonstrated for imaging photoresist patterns with high aspect ratio. In addition, these tips have been used to analyze Mars simulant dust grains, extremophile protein crystals, and DNA structure.
Display challenges resulting from the use of wide field of view imaging devices
NASA Astrophysics Data System (ADS)
Petty, Gregory J.; Fulton, Jack; Nicholson, Gail; Seals, Ean
2012-06-01
As focal plane array technologies advance and imagers increase in resolution, display technology must outpace the imaging improvements in order to adequately represent the complete data collection. Typical display devices tend to have an aspect ratio similar to 4:3 or 16:9, however a breed of Wide Field of View (WFOV) imaging devices exist that skew from the norm with aspect ratios as high as 5:1. This particular quality, when coupled with a high spatial resolution, presents a unique challenge for display devices. Standard display devices must choose between resizing the image data to fit the display and displaying the image data in native resolution and truncating potentially important information. The problem compounds when considering the applications; WFOV high-situationalawareness imagers are sought for space-limited military vehicles. Tradeoffs between these issues are assessed to the image quality of the WFOV sensor.
Hsu, Bing-Cheng
2018-01-01
Waxing is an important aspect of automobile detailing, aimed at protecting the finish of the car and preventing rust. At present, this delicate work is conducted manually due to the need for iterative adjustments to achieve acceptable quality. This paper presents a robotic waxing system in which surface images are used to evaluate the quality of the finish. An RGB-D camera is used to build a point cloud that details the sheet metal components to enable path planning for a robot manipulator. The robot is equipped with a multi-axis force sensor to measure and control the forces involved in the application and buffing of wax. Images of sheet metal components that were waxed by experienced car detailers were analyzed using image processing algorithms. A Gaussian distribution function and its parameterized values were obtained from the images for use as a performance criterion in evaluating the quality of surfaces prepared by the robotic waxing system. Waxing force and dwell time were optimized using a mathematical model based on the image-based criterion used to measure waxing performance. Experimental results demonstrate the feasibility of the proposed robotic waxing system and image-based performance evaluation scheme. PMID:29757940
Lin, Chi-Ying; Hsu, Bing-Cheng
2018-05-14
Waxing is an important aspect of automobile detailing, aimed at protecting the finish of the car and preventing rust. At present, this delicate work is conducted manually due to the need for iterative adjustments to achieve acceptable quality. This paper presents a robotic waxing system in which surface images are used to evaluate the quality of the finish. An RGB-D camera is used to build a point cloud that details the sheet metal components to enable path planning for a robot manipulator. The robot is equipped with a multi-axis force sensor to measure and control the forces involved in the application and buffing of wax. Images of sheet metal components that were waxed by experienced car detailers were analyzed using image processing algorithms. A Gaussian distribution function and its parameterized values were obtained from the images for use as a performance criterion in evaluating the quality of surfaces prepared by the robotic waxing system. Waxing force and dwell time were optimized using a mathematical model based on the image-based criterion used to measure waxing performance. Experimental results demonstrate the feasibility of the proposed robotic waxing system and image-based performance evaluation scheme.
Aerospace Technology Innovation. Volume 10
NASA Technical Reports Server (NTRS)
Turner, Janelle (Editor); Cousins, Liz (Editor); Bennett, Evonne (Editor); Vendette, Joel (Editor); West, Kenyon (Editor)
2002-01-01
Whether finding new applications for existing NASA technologies or developing unique marketing strategies to demonstrate them, NASA's offices are committed to identifying unique partnering opportunities. Through their efforts NASA leverages resources through joint research and development, and gains new insight into the core areas relevant to all NASA field centers. One of the most satisfying aspects of my job comes when I learn of a mission-driven technology that can be spun-off to touch the lives of everyday people. NASA's New Partnerships in Medical Diagnostic Imaging is one such initiative. Not only does it promise to provide greater dividends for the country's investment in aerospace research, but also to enhance the American quality of life. This issue of Innovation highlights the new NASA-sponsored initiative in medical imaging. Early in 2001, NASA announced the launch of the New Partnerships in Medical Diagnostic Imaging initiative to promote the partnership and commercialization of NASA technologies in the medical imaging industry. NASA and the medical imaging industry share a number of crosscutting technologies in areas such as high-performance detectors and image-processing tools. Many of the opportunities for joint development and technology transfer to the medical imaging market also hold the promise for future spin back to NASA.
Shin, Seung-Han; Lee, Yong-Suk; Kang, Jin-Woo; Noh, Dong-Young; Jung, Joon-Yong; Chung, Yang-Guk
2018-03-01
The location of the ulnar styloid process can be confusing because the radius and the hand rotate around the ulna. The purpose of this study was to identify the absolute location of the ulnar styloid process, which is independent of forearm pronation or supination, to use it as a reference for neutral forearm rotation on lateral radiographs of the wrist. Computed tomography (CT) images of 23 forearms taken with elbow flexion of 70° to 90° were analyzed. The axial CT images were reconstructed to be perpendicular to the distal ulnar shaft. The absolute location of the ulnar styloid process in this study was defined as the position of the ulnar styloid process on the axial plane of the ulnar head relative to the long axis of the humeral shaft with the elbow set in the position for standard lateral radiographs of the wrist. To identify in which direction the ulnar styloid is located on the axial plane of the ulnar head, the angle between "the line of humeral long axis projected on the axial plane of the ulna" and "the line passing the center of the ulnar head and the center of the ulnar styloid" was measured (ulnar styloid direction angle). To identify how volarly or dorsally the ulnar styloid should appear on the true lateral view of the wrist, the ratio of "the volar-dorsal diameter of the ulnar head" and "the distance between the volar-most aspect of the ulnar head and the center of the ulnar styloid" was calculated (ulnar styloid location ratio). The mean ulnar styloid direction angle was 12° dorsally. The mean ulnar styloid location ratio was 1:0.55. The ulnar styloid is located at nearly the ulnar-most (the opposite side of the humerus with the elbow flexed) and slightly dorsal aspects of the ulnar head on the axial plane. It should appear almost midway (55% dorsally) from the ulnar head on the standard lateral view of the wrist in neutral forearm rotation. These location references could help clinicians determine whether the forearm is in neutral or rotated position on an axial CT/magnetic resonance imaging scan or a lateral radiograph of the wrist.
Silicon Nanotips Antireflection Surface for Micro Sun Sensor
NASA Technical Reports Server (NTRS)
Bae, Sam Y.; Lee, Choonsup; Mobasser, Sohrab; Manohara, Harish
2006-01-01
We have developed a new technique to fabricate antireflection surface using silicon nano-tips for use on a micro sun sensor for Mars rovers. We have achieved randomly distributed nano-tips of radius spanning from 20 nm to 100 nm and aspect ratio of 200 using a two-step dry etching process. The 30(deg) specular reflectance at the target wavelength of 1 (mu)m is only about 0.09 %, nearly three orders of magnitude lower than that of bare silicon, and the hemispherical reflectance is 8%. By changing the density and aspect ratio of these nanotips, the change in reflectance is demonstrated. Using surfaces covered with these nano-tips, the critical problem of ghost images that are caused by multiple internal reflections in a micro sun sensor was solved.
NASA Technical Reports Server (NTRS)
Chao, Tien-Hsin; Stoner, William W.
1993-01-01
An optical neural network based on the neocognitron paradigm is introduced. A novel aspect of the architecture design is shift-invariant multichannel Fourier optical correlation within each processing layer. Multilayer processing is achieved by feeding back the ouput of the feature correlator interatively to the input spatial light modulator and by updating the Fourier filters. By training the neural net with characteristic features extracted from the target images, successful pattern recognition with intraclass fault tolerance and interclass discrimination is achieved. A detailed system description is provided. Experimental demonstrations of a two-layer neural network for space-object discrimination is also presented.
Automatic target recognition using a feature-based optical neural network
NASA Technical Reports Server (NTRS)
Chao, Tien-Hsin
1992-01-01
An optical neural network based upon the Neocognitron paradigm (K. Fukushima et al. 1983) is introduced. A novel aspect of the architectural design is shift-invariant multichannel Fourier optical correlation within each processing layer. Multilayer processing is achieved by iteratively feeding back the output of the feature correlator to the input spatial light modulator and updating the Fourier filters. By training the neural net with characteristic features extracted from the target images, successful pattern recognition with intra-class fault tolerance and inter-class discrimination is achieved. A detailed system description is provided. Experimental demonstration of a two-layer neural network for space objects discrimination is also presented.
Data protection and security issues of PACS
NASA Astrophysics Data System (ADS)
Bakker, Albert R.
1992-07-01
It is observed that the dataprotection aspects of PACS have hardly been explored, while for Hospital Information Systems (HIS) considerable attention has been paid to these aspects. In the dataprotection domain around HIS we distinguish the aspects data integrity (safety), usage integrity (confidentiality, privacy) and availability. A wide range of measures (dealing with hardware, software or organization/procedures) has been suggested to achieve adequate protection. For each system a selection of the suggested measures has to be made, where risk is balanced against costs. It seems that it is taken for granted that the usual measures as implemented for HIS will also be adequate for PACS. In this paper dataprotection aspects for PACS are discussed. Apart from similarities with the HIS situation also differences will be identified. In particular safeguarding the image databank requires special measured. Dataprotection should not be an add-on of the system, it should be taken into account in the design phase. As an illustration two alternatives for the organization of the image databank will be considered from the point of view of dataprotection. The one being consecutive historical storage of images, the other the clustering of images of the same patient on the same volume in the storage system.
System and method for the detection of anomalies in an image
Prasad, Lakshman; Swaminarayan, Sriram
2013-09-03
Preferred aspects of the present invention can include receiving a digital image at a processor; segmenting the digital image into a hierarchy of feature layers comprising one or more fine-scale features defining a foreground object embedded in one or more coarser-scale features defining a background to the one or more fine-scale features in the segmentation hierarchy; detecting a first fine-scale foreground feature as an anomaly with respect to a first background feature within which it is embedded; and constructing an anomalous feature layer by synthesizing spatially contiguous anomalous fine-scale features. Additional preferred aspects of the present invention can include detecting non-pervasive changes between sets of images in response at least in part to one or more difference images between the sets of images.
Rotation invariants of vector fields from orthogonal moments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Bo; Kostková, Jitka; Flusser, Jan
Vector field images are a type of new multidimensional data that appear in many engineering areas. Although the vector fields can be visualized as images, they differ from graylevel and color images in several aspects. In order to analyze them, special methods and algorithms must be originally developed or substantially adapted from the traditional image processing area. Here, we propose a method for the description and matching of vector field patterns under an unknown rotation of the field. Rotation of a vector field is so-called total rotation, where the action is applied not only on the spatial coordinates but alsomore » on the field values. Invariants of vector fields with respect to total rotation constructed from orthogonal Gaussian–Hermite moments and Zernike moments are introduced. Their numerical stability is shown to be better than that of the invariants published so far. We demonstrate their usefulness in a real world template matching application of rotated vector fields.« less
NASA Astrophysics Data System (ADS)
Cho, Hyo Sung; Woo, Tae Ho; Park, Chul Kyu
2016-10-01
Using the metal artifact property, it is analyzed for the X-ray computed tomography (CT) in the aspect of the security on the examined places like airport and surveillance areas. Since the importance of terror prevention strategy has been increased, the security application of X-ray CT has the significant remark. One shot X-ray image has the limitation to find out the exact shape to property in the closed box, which could be solved by the CT scanning without the tearing off the box in this work. Cleaner images can be obtained by the advanced technology if the CT scanning is utilized in the security purposes on the secured areas. A metal sample is treated by the metal artifact removal (MAR) method for the enhanced image. The mimicked explosive is experimented for the imaging processing application where the cleaner one is obtained. The procedure is explained and the further study is discussed.
NASA Technical Reports Server (NTRS)
Cramer, Alexander Krishnan
2014-01-01
This work covers the design and test of a machine vision algorithm for generating high- accuracy pitch and yaw pointing solutions relative to the sun on a high altitude balloon. It describes how images were constructed by focusing an image of the sun onto a plate printed with a pattern of small cross-shaped fiducial markers. Images of this plate taken with an off-the-shelf camera were processed to determine relative position of the balloon payload to the sun. The algorithm is broken into four problems: circle detection, fiducial detection, fiducial identification, and image registration. Circle detection is handled by an "Average Intersection" method, fiducial detection by a matched filter approach, and identification with an ad-hoc method based on the spacing between fiducials. Performance is verified on real test data where possible, but otherwise uses artificially generated data. Pointing knowledge is ultimately verified to meet the 20 arcsecond requirement.
Rotation invariants of vector fields from orthogonal moments
Yang, Bo; Kostková, Jitka; Flusser, Jan; ...
2017-09-11
Vector field images are a type of new multidimensional data that appear in many engineering areas. Although the vector fields can be visualized as images, they differ from graylevel and color images in several aspects. In order to analyze them, special methods and algorithms must be originally developed or substantially adapted from the traditional image processing area. Here, we propose a method for the description and matching of vector field patterns under an unknown rotation of the field. Rotation of a vector field is so-called total rotation, where the action is applied not only on the spatial coordinates but alsomore » on the field values. Invariants of vector fields with respect to total rotation constructed from orthogonal Gaussian–Hermite moments and Zernike moments are introduced. Their numerical stability is shown to be better than that of the invariants published so far. We demonstrate their usefulness in a real world template matching application of rotated vector fields.« less
MEG-BIDS, the brain imaging data structure extended to magnetoencephalography
Niso, Guiomar; Gorgolewski, Krzysztof J.; Bock, Elizabeth; Brooks, Teon L.; Flandin, Guillaume; Gramfort, Alexandre; Henson, Richard N.; Jas, Mainak; Litvak, Vladimir; T. Moreau, Jeremy; Oostenveld, Robert; Schoffelen, Jan-Mathijs; Tadel, Francois; Wexler, Joseph; Baillet, Sylvain
2018-01-01
We present a significant extension of the Brain Imaging Data Structure (BIDS) to support the specific aspects of magnetoencephalography (MEG) data. MEG measures brain activity with millisecond temporal resolution and unique source imaging capabilities. So far, BIDS was a solution to organise magnetic resonance imaging (MRI) data. The nature and acquisition parameters of MRI and MEG data are strongly dissimilar. Although there is no standard data format for MEG, we propose MEG-BIDS as a principled solution to store, organise, process and share the multidimensional data volumes produced by the modality. The standard also includes well-defined metadata, to facilitate future data harmonisation and sharing efforts. This responds to unmet needs from the multimodal neuroimaging community and paves the way to further integration of other techniques in electrophysiology. MEG-BIDS builds on MRI-BIDS, extending BIDS to a multimodal data structure. We feature several data-analytics software that have adopted MEG-BIDS, and a diverse sample of open MEG-BIDS data resources available to everyone. PMID:29917016
MEG-BIDS, the brain imaging data structure extended to magnetoencephalography.
Niso, Guiomar; Gorgolewski, Krzysztof J; Bock, Elizabeth; Brooks, Teon L; Flandin, Guillaume; Gramfort, Alexandre; Henson, Richard N; Jas, Mainak; Litvak, Vladimir; T Moreau, Jeremy; Oostenveld, Robert; Schoffelen, Jan-Mathijs; Tadel, Francois; Wexler, Joseph; Baillet, Sylvain
2018-06-19
We present a significant extension of the Brain Imaging Data Structure (BIDS) to support the specific aspects of magnetoencephalography (MEG) data. MEG measures brain activity with millisecond temporal resolution and unique source imaging capabilities. So far, BIDS was a solution to organise magnetic resonance imaging (MRI) data. The nature and acquisition parameters of MRI and MEG data are strongly dissimilar. Although there is no standard data format for MEG, we propose MEG-BIDS as a principled solution to store, organise, process and share the multidimensional data volumes produced by the modality. The standard also includes well-defined metadata, to facilitate future data harmonisation and sharing efforts. This responds to unmet needs from the multimodal neuroimaging community and paves the way to further integration of other techniques in electrophysiology. MEG-BIDS builds on MRI-BIDS, extending BIDS to a multimodal data structure. We feature several data-analytics software that have adopted MEG-BIDS, and a diverse sample of open MEG-BIDS data resources available to everyone.
Underwater Photogrammetry and 3d Reconstruction of Marble Cargos Shipwreck
NASA Astrophysics Data System (ADS)
Balletti, C.; Beltrame, C.; Costa, E.; Guerra, F.; Vernier, P.
2015-04-01
Nowadays archaeological and architectural surveys are based on the acquisition and processing of point clouds, allowing a high metric precision, essential prerequisite for a good documentation. Digital image processing and laser scanner have changed the archaeological survey campaign, from manual and direct survey to a digital one and, actually, multi-image photogrammetry is a good solution for the underwater archaeology. This technical documentation cannot operate alone, but it has to be supported by a topographical survey to georeference all the finds in the same reference system. In the last years the Ca' Foscari and IUAV University of Venice are conducting a research on integrated survey techniques to support underwater metric documentation. The paper will explain all the phases regarding the survey's design, images acquisition, topographic measure and the data processing of two Roman shipwrecks in south Sicily. The cargos of the shipwrecks are composed by huge marble blocks, but they are different for morphological characteristic of the sites, for the depth and for their distribution on the seabed. Photogrammetrical and topographical surveys were organized in two distinct methods, especially for the second one, due to the depth that have allowed an experimentation of GPS RTK's measurements on one shipwreck. Moreover, this kind of three-dimensional documentation is useful for educational and dissemination aspect, for the ease of understanding by wide public.
NASA Astrophysics Data System (ADS)
Lima Neto, Irineu A.; Misságia, Roseane M.; Ceia, Marco A.; Archilha, Nathaly L.; Oliveira, Lucas C.
2014-11-01
Carbonate reservoirs exhibit heterogeneous pore systems and a wide variety of grain types, which affect the rock's elastic properties and the reservoir parameter relationships. To study the Albian carbonates in the Campos Basin, a methodology is proposed to predict the amount of microporosity and the representative aspect ratio of these inclusions. The method assumes three pore-space scales in two representative inclusion scenarios: 1) a macro-mesopore median aspect ratio from the thin-section digital image analysis (DIA) and 2) a microporosity aspect ratio predicted based on the measured P-wave velocities. Through a laboratory analysis of 10 grainstone core samples of the Albian age, the P- and S-wave velocities (Vp and Vs) are evaluated at effective pressures of 0-10 MPa. The analytical theories in the proposed methodology are functions of the aspect ratios from the differential effective medium (DEM) theory, the macro-mesopore system recognized from the DIA, the amount of microporosity determined by the difference between the porosities estimated from laboratorial helium-gas and the thin-section petrographic images, and the P-wave velocities under dry effective pressure conditions. The DIA procedure is applied to estimate the local and global parameters, and the textural implications concerning ultrasonic velocities and image resolution. The macro-mesopore inclusions contribute to stiffer rocks and higher velocities, whereas the microporosity inclusions contribute to softer rocks and lower velocities. We observe a high potential for this methodology, which uses the microporosity aspect ratio inverted from Vp to predict Vs with a good agreement. The results acceptably characterize the Albian grainstones. The representative macro-mesopore aspect ratio is 0.5, and the inverted microporosity aspect ratio ranges from 0.01 to 0.07. The effective pressure induced an effect of slight porosity reduction during the triaxial tests, mainly in the microporosity inclusions, slightly changing the amount and the aspect ratio of the microporosity.
Informatics in radiology: Efficiency metrics for imaging device productivity.
Hu, Mengqi; Pavlicek, William; Liu, Patrick T; Zhang, Muhong; Langer, Steve G; Wang, Shanshan; Place, Vicki; Miranda, Rafael; Wu, Teresa Tong
2011-01-01
Acute awareness of the costs associated with medical imaging equipment is an ever-present aspect of the current healthcare debate. However, the monitoring of productivity associated with expensive imaging devices is likely to be labor intensive, relies on summary statistics, and lacks accepted and standardized benchmarks of efficiency. In the context of the general Six Sigma DMAIC (design, measure, analyze, improve, and control) process, a World Wide Web-based productivity tool called the Imaging Exam Time Monitor was developed to accurately and remotely monitor imaging efficiency with use of Digital Imaging and Communications in Medicine (DICOM) combined with a picture archiving and communication system. Five device efficiency metrics-examination duration, table utilization, interpatient time, appointment interval time, and interseries time-were derived from DICOM values. These metrics allow the standardized measurement of productivity, to facilitate the comparative evaluation of imaging equipment use and ongoing efforts to improve efficiency. A relational database was constructed to store patient imaging data, along with device- and examination-related data. The database provides full access to ad hoc queries and can automatically generate detailed reports for administrative and business use, thereby allowing staff to monitor data for trends and to better identify possible changes that could lead to improved productivity and reduced costs in association with imaging services. © RSNA, 2011.
The EarthKAM project: creating space imaging tools for teaching and learning
NASA Astrophysics Data System (ADS)
Dodson, Holly; Levin, Paula; Ride, Sally; Souviney, Randall
2000-07-01
The EarthKAM Project is a NASA-supported partnership of secondary and university students with Earth Science and educational researchers. This report describes an ongoing series of activities that more effectively integrate Earth images into classroom instruction. In this project, students select and analyze images of the Earth taken during Shuttle flights and use the tools of modern science (computers, data analysis tools and the Internet) to disseminate the images and results of their research. A related study, the Visualizing Earth Project, explores in greater detail the cognitive aspects of image processing and the educational potential of visualizations in science teaching and learning. The content and organization of the EarthKAM datasystem of images and metadata are also described. An associated project is linking this datasystem of images with the Getty Thesaurus of Geographic Names, which will allow users to access a wide range of geographic and political information for the regions shown in EarthKAM images. Another project will provide tools for automated feature extraction from EarthKAM images. In order to make EarthKAM resources available to a larger number of schools, the next important goal is to create an integrated datasystem that combines iterative resource validation and publication, with multimedia management of instructional materials.
NASA Astrophysics Data System (ADS)
Mazurowski, Maciej A.; Clark, Kal; Czarnek, Nicholas M.; Shamsesfandabadi, Parisa; Peters, Katherine B.; Saha, Ashirbani
2017-03-01
Recent studies showed that genomic analysis of lower grade gliomas can be very effective for stratification of patients into groups with different prognosis and proposed specific genomic classifications. In this study, we explore the association of one of those genomic classifications with imaging parameters to determine whether imaging could serve a similar role to genomics in cancer patient treatment. Specifically, we analyzed imaging and genomics data for 110 patients from 5 institutions from The Cancer Genome Atlas and The Cancer Imaging Archive datasets. The analyzed imaging data contained preoperative FLAIR sequence for each patient. The images were analyzed using the in-house algorithms which quantify 2D and 3D aspects of the tumor shape. Genomic data consisted of a cluster of clusters classification proposed in a very recent and leading publication in the field of lower grade glioma genomics. Our statistical analysis showed that there is a strong association between the tumor cluster-of-clusters subtype and two imaging features: bounding ellipsoid volume ratio and angular standard deviation. This result shows high promise for the potential use of imaging as a surrogate measure for genomics in the decision process regarding treatment of lower grade glioma patients.
Modeling semantic aspects for cross-media image indexing.
Monay, Florent; Gatica-Perez, Daniel
2007-10-01
To go beyond the query-by-example paradigm in image retrieval, there is a need for semantic indexing of large image collections for intuitive text-based image search. Different models have been proposed to learn the dependencies between the visual content of an image set and the associated text captions, then allowing for the automatic creation of semantic indices for unannotated images. The task, however, remains unsolved. In this paper, we present three alternatives to learn a Probabilistic Latent Semantic Analysis model (PLSA) for annotated images, and evaluate their respective performance for automatic image indexing. Under the PLSA assumptions, an image is modeled as a mixture of latent aspects that generates both image features and text captions, and we investigate three ways to learn the mixture of aspects. We also propose a more discriminative image representation than the traditional Blob histogram, concatenating quantized local color information and quantized local texture descriptors. The first learning procedure of a PLSA model for annotated images is a standard EM algorithm, which implicitly assumes that the visual and the textual modalities can be treated equivalently. The other two models are based on an asymmetric PLSA learning, allowing to constrain the definition of the latent space on the visual or on the textual modality. We demonstrate that the textual modality is more appropriate to learn a semantically meaningful latent space, which translates into improved annotation performance. A comparison of our learning algorithms with respect to recent methods on a standard dataset is presented, and a detailed evaluation of the performance shows the validity of our framework.
NASA Astrophysics Data System (ADS)
Suponenkovs, Artjoms; Glazs, Aleksandrs; Platkajis, Ardis
2017-03-01
The aim of this paper is to describe the new methods for analyzing knee articular cartilage degeneration. The most important aspects regarding research about magnetic resonance imaging, knee joint anatomy, stages of knee osteoarthritis, medical image segmentation and relaxation times calculation. This paper proposes new methods for relaxation times calculation and medical image segmentation. The experimental part describes the most important aspect regarding analysing of articular cartilage relaxation times changing. This part contains experimental results, which show the codependence between relaxation times and organic structure. These experimental results and proposed methods can be helpful for early osteoarthritis diagnostics.
Variable electronic shutter in CMOS imager with improved anti smearing techniques
NASA Technical Reports Server (NTRS)
Pain, Bedabrata (Inventor)
2005-01-01
A leakage compensated snapshot imager provides a number of different aspects to prevent smear and other problems in a snapshot imager. The area where the imager is formed may be biased in a way that prevents photo carriers including electrons and holes from reaching a storage area. In addition, a number of different aspects may improve the efficiency. The capacitance per unit area of the storage area may be one, two or more orders of magnitude greater than the capacitance per-unit area of the photodiode. In addition, a ratio between photodiode capacitance and storage area capacitance is maintained larger than 0.7.
Procedure for Automated Eddy Current Crack Detection in Thin Titanium Plates
NASA Technical Reports Server (NTRS)
Wincheski, Russell A.
2012-01-01
This procedure provides the detailed instructions for conducting Eddy Current (EC) inspections of thin (5-30 mils) titanium membranes with thickness and material properties typical of the development of Ultra-Lightweight diaphragm Tanks Technology (ULTT). The inspection focuses on the detection of part-through, surface breaking fatigue cracks with depths between approximately 0.002" and 0.007" and aspect ratios (a/c) of 0.2-1.0 using an automated eddy current scanning and image processing technique.
A Fast MEANSHIFT Algorithm-Based Target Tracking System
Sun, Jian
2012-01-01
Tracking moving targets in complex scenes using an active video camera is a challenging task. Tracking accuracy and efficiency are two key yet generally incompatible aspects of a Target Tracking System (TTS). A compromise scheme will be studied in this paper. A fast mean-shift-based Target Tracking scheme is designed and realized, which is robust to partial occlusion and changes in object appearance. The physical simulation shows that the image signal processing speed is >50 frame/s. PMID:22969397
The Effect of Sub-Aperture in DRIA Framework Applied on Multi-Aspect PolSAR Data
NASA Astrophysics Data System (ADS)
Xue, Feiteng; Yin, Qiang; Lin, Yun; Hong, Wen
2016-08-01
Multi-aspect SAR is a new remote sensing technology, achieves consecutive data in large look angle as platform moves. Multi- aspect observation brings higher resolution and SNR to SAR picture. Multi-aspect PolSAR data can increase the accuracy of target identify and classification because it contains the 3-D polarimetric scattering properties.DRIA(detecting-removing-incoherent-adding)framework is a multi-aspect PolSAR data processing method. In this method, the anisotropic and isotropic scattering is separated by maximum- likelihood ratio test. The anisotropic scattering is removed to gain a removal series. The isotropic scattering is incoherent added to gain a high resolution picture. The removal series describes the anisotropic scattering property and is used in features extraction and classification.This article focuses on the effect brought by difference of sub-aperture numbers in anisotropic scattering detection and removal. The more sub-apertures are, the less look angle is. Artificial target has anisotropic scattering because of Bragg resonances. The increase of sub-aperture number brings more accurate observation in azimuth though the quality of each single image may loss. The accuracy of classification in agricultural fields is affected by the anisotropic scattering brought by Bragg resonances. The size of the sub-aperture has a significant effect in the removal result of Bragg resonances.
NASA Astrophysics Data System (ADS)
Wang, Zhun; Cheng, Feiyan; Shi, Junsheng; Huang, Xiaoqiao
2018-01-01
In a low-light scene, capturing color images needs to be at a high-gain setting or a long-exposure setting to avoid a visible flash. However, such these setting will lead to color images with serious noise or motion blur. Several methods have been proposed to improve a noise-color image through an invisible near infrared flash image. A novel method is that the luminance component and the chroma component of the improved color image are estimated from different image sources [1]. The luminance component is estimated mainly from the NIR image via a spectral estimation, and the chroma component is estimated from the noise-color image by denoising. However, it is challenging to estimate the luminance component. This novel method to estimate the luminance component needs to generate the learning data pairs, and the processes and algorithm are complex. It is difficult to achieve practical application. In order to reduce the complexity of the luminance estimation, an improved luminance estimation algorithm is presented in this paper, which is to weight the NIR image and the denoised-color image and the weighted coefficients are based on the mean value and standard deviation of both images. Experimental results show that the same fusion effect at aspect of color fidelity and texture quality is achieved, compared the proposed method with the novel method, however, the algorithm is more simple and practical.
Simulation of digital mammography images
NASA Astrophysics Data System (ADS)
Workman, Adam
2005-04-01
A number of different technologies are available for digital mammography. However, it is not clear how differences in the physical performance aspects of the different imaging technologies affect clinical performance. Randomised controlled trials provide a means of gaining information on clinical performance however do not provide direct comparison of the different digital imaging technologies. This work describes a method of simulating the performance of different digital mammography systems. The method involves modifying the imaging performance parameters of images from a small field of view (SFDM), high resolution digital imaging system used for spot imaging. Under normal operating conditions this system produces images with higher signal-to-noise ratio (SNR) over a wide spatial frequency range than current full field digital mammography (FFDM) systems. The SFDM images can be 'degraded" by computer processing to simulate the characteristics of a FFDM system. Initial work characterised the physical performance (MTF, NPS) of the SFDM detector and developed a model and method for simulating signal transfer and noise properties of a FFDM system. It was found that the SNR properties of the simulated FFDM images were very similar to those measured from an actual FFDM system verifying the methodology used. The application of this technique to clinical images from the small field system will allow the clinical performance of different FFDM systems to be simulated and directly compared using the same clinical image datasets.
EduGATE - basic examples for educative purpose using the GATE simulation platform.
Pietrzyk, Uwe; Zakhnini, Abdelhamid; Axer, Markus; Sauerzapf, Sophie; Benoit, Didier; Gaens, Michaela
2013-02-01
EduGATE is a collection of basic examples to introduce students to the fundamental physical aspects of medical imaging devices. It is based on the GATE platform, which has received a wide acceptance in the field of simulating medical imaging devices including SPECT, PET, CT and also applications in radiation therapy. GATE can be configured by commands, which are, for the sake of simplicity, listed in a collection of one or more macro files to set up phantoms, multiple types of sources, detection device, and acquisition parameters. The aim of the EduGATE is to use all these helpful features of GATE to provide insights into the physics of medical imaging by means of a collection of very basic and simple GATE macros in connection with analysis programs based on ROOT, a framework for data processing. A graphical user interface to define a configuration is also included. Copyright © 2012. Published by Elsevier GmbH.
An evaluation of EREP (Skylab) and ERTS imagery for integrated natural resources survey
NASA Technical Reports Server (NTRS)
Vangenderen, J. L. (Principal Investigator)
1973-01-01
The author has identified the following significant results. An experimental procedure has been devised and is being tested for natural resource surveys to cope with the problems of interpreting and processing the large quantities of data provided by Skylab and ERTS. Some basic aspects of orbital imagery such as scale, the role of repetitive coverage, and types of sensors are being examined in relation to integrated surveys of natural resources and regional development planning. Extrapolation away from known ground conditions, a fundamental technique for mapping resources, becomes very effective when used on orbital imagery supported by field mapping. Meaningful boundary delimitations can be made on orbital images using various image enhancement techniques. To meet the needs of many developing countries, this investigation into the use of satellite imagery for integrated resource surveys involves the analysis of the images by means of standard visual photointerpretation methods.
Biomedical Applications of Nanodiamonds: An Overview.
Passeri, D; Rinaldi, F; Ingallina, C; Carafa, M; Rossi, M; Terranova, M L; Marianecci, C
2015-02-01
Nanodiamonds are a novel class of nanomaterials which have raised much attention for application in biomedical field, as they combine the possibility of being produced on large scale using relatively inexpensive synthetic processes, of being fluorescent as a consequence of the presence of nitrogen vacancies, of having their surfaces functionalized, and of having good biocompatibility. Among other applications, we mainly focus on drug delivery, including cell interaction, targeting, cancer therapy, gene and protein delivery. In addition, nanodiamonds for bone and dental implants and for antibacterial use is discussed. Techniques for detection and imaging of nanodiamonds in biological tissues are also reviewed, including electron microscopy, fluorescence microscopy, Raman mapping, atomic force microscopy, thermal imaging, magnetic resonance imaging, and positron emission tomography, either in vitro, in vivo, or ex vivo. Toxicological aspects related to the use of nanodiamonds are also discussed. Finally, patents, preclinical and clinical trials based on the use of nanodiamonds for biomedical applications are reviewed.
Location precision analysis of stereo thermal anti-sniper detection system
NASA Astrophysics Data System (ADS)
He, Yuqing; Lu, Ya; Zhang, Xiaoyan; Jin, Weiqi
2012-06-01
Anti-sniper detection devices are the urgent requirement in modern warfare. The precision of the anti-sniper detection system is especially important. This paper discusses the location precision analysis of the anti-sniper detection system based on the dual-thermal imaging system. It mainly discusses the following two aspects which produce the error: the digital quantitative effects of the camera; effect of estimating the coordinate of bullet trajectory according to the infrared images in the process of image matching. The formula of the error analysis is deduced according to the method of stereovision model and digital quantitative effects of the camera. From this, we can get the relationship of the detecting accuracy corresponding to the system's parameters. The analysis in this paper provides the theory basis for the error compensation algorithms which are put forward to improve the accuracy of 3D reconstruction of the bullet trajectory in the anti-sniper detection devices.
Friedman, Tamir; Michalski, Mark; Goodman, T Rob; Brown, J Elliott
2016-03-01
Three-dimensional (3D) printing has recently erupted into the medical arena due to decreased costs and increased availability of printers and software tools. Due to lack of detailed information in the medical literature on the methods for 3D printing, we have reviewed the medical and engineering literature on the various methods for 3D printing and compiled them into a practical "how to" format, thereby enabling the novice to start 3D printing with very limited funds. We describe (1) background knowledge, (2) imaging parameters, (3) software, (4) hardware, (5) post-processing, and (6) financial aspects required to cost-effectively reproduce a patient's disease ex vivo so that the patient, engineer and surgeon may hold the anatomy and associated pathology in their hands.
Real-time generation of infrared ocean scene based on GPU
NASA Astrophysics Data System (ADS)
Jiang, Zhaoyi; Wang, Xun; Lin, Yun; Jin, Jianqiu
2007-12-01
Infrared (IR) image synthesis for ocean scene has become more and more important nowadays, especially for remote sensing and military application. Although a number of works present ready-to-use simulations, those techniques cover only a few possible ways of water interacting with the environment. And the detail calculation of ocean temperature is rarely considered by previous investigators. With the advance of programmable features of graphic card, many algorithms previously limited to offline processing have become feasible for real-time usage. In this paper, we propose an efficient algorithm for real-time rendering of infrared ocean scene using the newest features of programmable graphics processors (GPU). It differs from previous works in three aspects: adaptive GPU-based ocean surface tessellation, sophisticated balance equation of thermal balance for ocean surface, and GPU-based rendering for infrared ocean scene. Finally some results of infrared image are shown, which are in good accordance with real images.
European Union RACE program contributions to digital audiovisual communications and services
NASA Astrophysics Data System (ADS)
de Albuquerque, Augusto; van Noorden, Leon; Badique', Eric
1995-02-01
The European Union RACE (R&D in advanced communications technologies in Europe) and the future ACTS (advanced communications technologies and services) programs have been contributing and continue to contribute to world-wide developments in audio-visual services. The paper focuses on research progress in: (1) Image data compression. Several methods of image analysis leading to the use of encoders based on improved hybrid DCT-DPCM (MPEG or not), object oriented, hybrid region/waveform or knowledge-based coding methods are discussed. (2) Program production in the aspects of 3D imaging, data acquisition, virtual scene construction, pre-processing and sequence generation. (3) Interoperability and multimedia access systems. The diversity of material available and the introduction of interactive or near- interactive audio-visual services led to the development of prestandards for video-on-demand (VoD) and interworking of multimedia services storage systems and customer premises equipment.
Language/culture/mind/brain. Progress at the margins between disciplines.
Kuhl, P K; Tsao, F M; Liu, H M; Zhang, Y; De Boer, B
2001-05-01
At the forefront of research on language are new data demonstrating infants' strategies in the early acquisition of language. The data show that infants perceptually "map" critical aspects of ambient language in the first year of life before they can speak. Statistical and abstract properties of speech are picked up through exposure to ambient language. Moreover, linguistic experience alters infants' perception of speech, warping perception in a way that enhances native-language speech processing. Infants' strategies are unexpected and unpredicted by historical views. At the same time, research in three additional disciplines is contributing to our understanding of language and its acquisition by children. Cultural anthropologists are demonstrating the universality of adult speech behavior when addressing infants and children across cultures, and this is creating a new view of the role adult speakers play in bringing about language in the child. Neuroscientists, using the techniques of modern brain imaging, are revealing the temporal and structural aspects of language processing by the brain and suggesting new views of the critical period for language. Computer scientists, modeling the computational aspects of childrens' language acquisition, are meeting success using biologically inspired neural networks. Although a consilient view cannot yet be offered, the cross-disciplinary interaction now seen among scientists pursuing one of humans' greatest achievements, language, is quite promising.
NASA Technical Reports Server (NTRS)
LaBonte, Barry J.
2004-01-01
A small amount of work has been done on this project; the strategy to be adopted has been better defined, though no experimental work has been started. 1) Wavefront error signals: The best choice appears use a lenslet array at a pupil image to produce defocused image pairs for each subaperture. Then use the method proposed by Molodij et al. to produce subaperture curvature signals. Basically, this method samples a moderate number of locations in the image where the value of the image Laplacian is high, then taking the curvature signal from the difference of the Laplacians of the extrafocal images at those locations. The tip-tilt error is obtained from the temporal dependence of the first spatial derivatives of an in-focus image, at selected locations where these derivatives are significant. The wavefront tilt can be obtained from the full-aperture image. 2) Extrafocal image generation: The important aspect here is to generate symmetrically defocused images, with dynamically adjustable defocus. The adjustment is needed because larger defocus is required before the feedback loop is closed, and at times when the seeing is worse. It may be that the usual membrane mirror is the best choice, though other options should be explored. 3) Detector: Since the proposed sensor is to work on solar granulation, rather than a point source, an array detector for each subaperture is required. A fast CMOS camera such as that developed by the National Solar Observatory would be a satisfactory choice. 4) Processing: Processing requirements have not been defined in detail, though significantly fewer operations per cycle are required than for a correlation tracker.
Retrieval and classification of food images.
Farinella, Giovanni Maria; Allegra, Dario; Moltisanti, Marco; Stanco, Filippo; Battiato, Sebastiano
2016-10-01
Automatic food understanding from images is an interesting challenge with applications in different domains. In particular, food intake monitoring is becoming more and more important because of the key role that it plays in health and market economies. In this paper, we address the study of food image processing from the perspective of Computer Vision. As first contribution we present a survey of the studies in the context of food image processing from the early attempts to the current state-of-the-art methods. Since retrieval and classification engines able to work on food images are required to build automatic systems for diet monitoring (e.g., to be embedded in wearable cameras), we focus our attention on the aspect of the representation of the food images because it plays a fundamental role in the understanding engines. The food retrieval and classification is a challenging task since the food presents high variableness and an intrinsic deformability. To properly study the peculiarities of different image representations we propose the UNICT-FD1200 dataset. It was composed of 4754 food images of 1200 distinct dishes acquired during real meals. Each food plate is acquired multiple times and the overall dataset presents both geometric and photometric variabilities. The images of the dataset have been manually labeled considering 8 categories: Appetizer, Main Course, Second Course, Single Course, Side Dish, Dessert, Breakfast, Fruit. We have performed tests employing different representations of the state-of-the-art to assess the related performances on the UNICT-FD1200 dataset. Finally, we propose a new representation based on the perceptual concept of Anti-Textons which is able to encode spatial information between Textons outperforming other representations in the context of food retrieval and Classification. Copyright © 2016 Elsevier Ltd. All rights reserved.
Geostationary Imaging FTS (GIFTS) Data Processing: Measurement Simulation and Compression
NASA Technical Reports Server (NTRS)
Huang, Hung-Lung; Revercomb, H. E.; Thom, J.; Antonelli, P. B.; Osborne, B.; Tobin, D.; Knuteson, R.; Garcia, R.; Dutcher, S.; Li, J.
2001-01-01
GIFTS (Geostationary Imaging Fourier Transform Spectrometer), a forerunner of next generation geostationary satellite weather observing systems, will be built to fly on the NASA EO-3 geostationary orbit mission in 2004 to demonstrate the use of large area detector arrays and readouts. Timely high spatial resolution images and quantitative soundings of clouds, water vapor, temperature, and pollutants of the atmosphere for weather prediction and air quality monitoring will be achieved. GIFTS is novel in terms of providing many scientific returns that traditionally can only be achieved by separate advanced imaging and sounding systems. GIFTS' ability to obtain half-hourly high vertical density wind over the full earth disk is revolutionary. However, these new technologies bring forth many challenges for data transmission, archiving, and geophysical data processing. In this paper, we will focus on the aspect of data volume and downlink issues by conducting a GIFTS data compression experiment. We will discuss the scenario of using principal component analysis as a foundation for atmospheric data retrieval and compression of uncalibrated and un-normalized interferograms. The effects of compression on the degradation of the signal and noise reduction in interferogram and spectral domains will be highlighted. A simulation system developed to model the GIFTS instrument measurements is described in detail.
Thermal Imaging Applied to Cryocrystallography: Cryocooling and Beam Heating (Part I)
NASA Technical Reports Server (NTRS)
Snell, Edward; Bellamy, Henry; Rosenbaum, Gerd; vanderWoerd, Mark; Kazmierczak, Michael
2006-01-01
Thermal imaging provides a non-invasive method to study both the cryocooling process and the heating due to the X-ray beam interaction with a sample. The method has been used successfully to image cryocooling in a number of experimental situations, i.e. cooling as a function of sample volume and as a function of cryostream orientation. Although there are experimental limitations to the method, it has proved a powerful technique to aid cryocrystallography development. Due to the rapid spatial temperature information provided about the sample it is also a powerful tool in the testing of mathematical models. Recently thermal imaging has been used to measure the temperature distribution on both a model and typical crystal samples illuminated with an X-ray beam produced by an undulator. A brief overview of thermal imaging and previous results will be presented. In addition, a detailed description of the calibration and experimental aspects of the beam heating measurements will be described. This will complement the following talk on the mathematical modeling and analysis of the results.
Sliding Window-Based Region of Interest Extraction for Finger Vein Images
Yang, Lu; Yang, Gongping; Yin, Yilong; Xiao, Rongyang
2013-01-01
Region of Interest (ROI) extraction is a crucial step in an automatic finger vein recognition system. The aim of ROI extraction is to decide which part of the image is suitable for finger vein feature extraction. This paper proposes a finger vein ROI extraction method which is robust to finger displacement and rotation. First, we determine the middle line of the finger, which will be used to correct the image skew. Then, a sliding window is used to detect the phalangeal joints and further to ascertain the height of ROI. Last, for the corrective image with certain height, we will obtain the ROI by using the internal tangents of finger edges as the left and right boundary. The experimental results show that the proposed method can extract ROI more accurately and effectively compared with other methods, and thus improve the performance of finger vein identification system. Besides, to acquire the high quality finger vein image during the capture process, we propose eight criteria for finger vein capture from different aspects and these criteria should be helpful to some extent for finger vein capture. PMID:23507824
Ding, Qiuning; Tao, Chao; Liu, Xiaojun
2017-03-20
Speed-of-sound and optical absorption reflect the structure and function of tissues from different aspects. A dual-mode microscopy system based on a concentric annular ultrasound array is proposed to simultaneously acquire the long depth-of-field images of speed-of-sound and optical absorption of inhomogeneous samples. First, speed-of-sound is decoded from the signal delay between each element of the annular array. The measured speed-of-sound could not only be used as an image contrast, but also improve the resolution and accuracy of spatial location of photoacoustic image in inhomogeneous acoustic media. Secondly, benefitting from dynamic focusing of annular array and the measured speed-of-sound, it is achieved an advanced acoustic-resolution photoacoustic microscopy with a precise position and a long depth-of-field. The performance of the dual-mode imaging system has been experimentally examined by using a custom-made annular array. The proposed dual-mode microscopy might have the significances in monitoring the biological physiological and pathological processes.
Synthetic Aperture Sonar Processing with MMSE Estimation of Image Sample Values
2016-12-01
UNCLASSIFIED/UNLIMITED 13. SUPPLEMENTARY NOTES 14. ABSTRACT MMSE (minimum mean- square error) target sample estimation using non-orthogonal basis...orthogonal, they can still be used in a minimum mean‐ square error (MMSE) estimator that models the object echo as a weighted sum of the multi‐aspect basis...problem. 3 Introduction Minimum mean‐ square error (MMSE) estimation is applied to target imaging with synthetic aperture
NASA Astrophysics Data System (ADS)
Niederheiser, R.; Rutzinger, M.; Bremer, M.; Wichmann, V.
2018-04-01
The investigation of changes in spatial patterns of vegetation and identification of potential micro-refugia requires detailed topographic and terrain information. However, mapping alpine topography at very detailed scales is challenging due to limited accessibility of sites. Close-range sensing by photogrammetric dense matching approaches based on terrestrial images captured with hand-held cameras offers a light-weight and low-cost solution to retrieve high-resolution measurements even in steep terrain and at locations, which are difficult to access. We propose a novel approach for rapid capturing of terrestrial images and a highly automated processing chain for retrieving detailed dense point clouds for topographic modelling. For this study, we modelled 249 plot locations. For the analysis of vegetation distribution and location properties, topographic parameters, such as slope, aspect, and potential solar irradiation were derived by applying a multi-scale approach utilizing voxel grids and spherical neighbourhoods. The result is a micro-topography archive of 249 alpine locations that includes topographic parameters at multiple scales ready for biogeomorphological analysis. Compared with regional elevation models at larger scales and traditional 2D gridding approaches to create elevation models, we employ analyses in a fully 3D environment that yield much more detailed insights into interrelations between topographic parameters, such as potential solar irradiation, surface area, aspect and roughness.
Feature and Intensity Based Medical Image Registration Using Particle Swarm Optimization.
Abdel-Basset, Mohamed; Fakhry, Ahmed E; El-Henawy, Ibrahim; Qiu, Tie; Sangaiah, Arun Kumar
2017-11-03
Image registration is an important aspect in medical image analysis, and kinds use in a variety of medical applications. Examples include diagnosis, pre/post surgery guidance, comparing/merging/integrating images from multi-modal like Magnetic Resonance Imaging (MRI), and Computed Tomography (CT). Whether registering images across modalities for a single patient or registering across patients for a single modality, registration is an effective way to combine information from different images into a normalized frame for reference. Registered datasets can be used for providing information relating to the structure, function, and pathology of the organ or individual being imaged. In this paper a hybrid approach for medical images registration has been developed. It employs a modified Mutual Information (MI) as a similarity metric and Particle Swarm Optimization (PSO) method. Computation of mutual information is modified using a weighted linear combination of image intensity and image gradient vector flow (GVF) intensity. In this manner, statistical as well as spatial image information is included into the image registration process. Maximization of the modified mutual information is effected using the versatile Particle Swarm Optimization which is developed easily with adjusted less parameter. The developed approach has been tested and verified successfully on a number of medical image data sets that include images with missing parts, noise contamination, and/or of different modalities (CT, MRI). The registration results indicate the proposed model as accurate and effective, and show the posture contribution in inclusion of both statistical and spatial image data to the developed approach.
Improving Vintage Seismic Data Quality through Implementation of Advance Processing Techniques
NASA Astrophysics Data System (ADS)
Latiff, A. H. Abdul; Boon Hong, P. G.; Jamaludin, S. N. F.
2017-10-01
It is essential in petroleum exploration to have high resolution subsurface images, both vertically and horizontally, in uncovering new geological and geophysical aspects of our subsurface. The lack of success may have been from the poor imaging quality which led to inaccurate analysis and interpretation. In this work, we re-processed the existing seismic dataset with an emphasis on two objectives. Firstly, to produce a better 3D seismic data quality with full retention of relative amplitudes and significantly reduce seismic and structural uncertainty. Secondly, to facilitate further prospect delineation through enhanced data resolution, fault definitions and events continuity, particularly in syn-rift section and basement cover contacts and in turn, better understand the geology of the subsurface especially in regard to the distribution of the fluvial and channel sands. By adding recent, state-of-the-art broadband processing techniques such as source and receiver de-ghosting, high density velocity analysis and shallow water de-multiple, the final results produced a better overall reflection detail and frequency in specific target zones, particularly in the deeper section.
2001 Mars Odyssey THEMIS: Thermophysics at a New Local Time
NASA Astrophysics Data System (ADS)
Hamilton, V. E.; Christensen, P. R.
2017-12-01
During its sixth extended mission, the 2001 Mars Odyssey transitioned to a new, rarely-seen, post-sunset (morning daylight) local time designed to reduce stress on the spacecraft. Since then, Thermal Emission Imaging System (THEMIS) observations have provided an unprecedented opportunity to investigate dynamic phenomena in the atmosphere and on the surface. In this new local time ( 6:45 am/pm) orbit, Odyssey's camera is acquiring expanded diurnal thermal imaging coverage, providing insight into surface texture, layering, and ice content, as well as dynamic, temperature-dependent surface, atmospheric, and polar processes. New THEMIS observations at dawn and dusk local times are filling major gaps in current knowledge about the diurnal variation of clouds, hazes and surface frost. In this presentation, we will highlight some of these data and discuss the unique scientific results that can be obtained from Mars Odyssey THEMIS observations, including: insights into potential past and present habitability of Mars, the processes and history of climate, the nature and evolution of geologic processes, and aspects of the environment relevant to future human exploration.
Medhi, Jyoti Prakash; Dandapat, Samarendra
2016-07-01
Prolonged diabetes causes severe damage to the vision through leakage of blood and blood constituents over the retina. The effect of the leakage becomes more threatening when these abnormalities involve the macula. This condition is known as diabetic maculopathy and it leads to blindness, if not treated in time. Early detection and proper diagnosis can help in preventing this irreversible damage. To achieve this, the possible way is to perform retinal screening at regular intervals. But the ratio of ophthalmologists to patients is very small and the process of evaluation is time consuming. Here, the automatic methods for analyzing retinal/fundus images prove handy and help the ophthalmologists to screen at a faster rate. Motivated from this aspect, an automated method for detection and analysis of diabetic maculopathy is proposed in this work. The method is implemented in two stages. The first stage involves preprocessing required for preparing the image for further analysis. During this stage the input image is enhanced and the optic disc is masked to avoid false detection during bright lesion identification. The second stage is maculopathy detection and its analysis. Here, the retinal lesions including microaneurysms, hemorrhages and exudates are identified by processing the green and hue plane color images. The macula and the fovea locations are determined using intensity property of processed red plane image. Different circular regions are thereafter marked in the neighborhood of the macula. The presence of lesions in these regions is identified to confirm positive maculopathy. Later, the information is used for evaluating its severity. The principal advantage of the proposed algorithm is, utilization of the relation of blood vessels with optic disc and macula, which enhances the detection process. Proper usage of various color plane information sequentially enables the algorithm to perform better. The method is tested on various publicly available databases consisting of both normal and maculopathy images. The algorithm detects fovea with an accuracy of 98.92% when applied on 1374 images. The average specificity and sensitivity of the proposed method for maculopathy detection are obtained as 98.05% and 98.86% respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.
Neurophysiological correlates of relatively enhanced local visual search in autistic adolescents.
Manjaly, Zina M; Bruning, Nicole; Neufang, Susanne; Stephan, Klaas E; Brieber, Sarah; Marshall, John C; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Fink, Gereon R
2007-03-01
Previous studies found normal or even superior performance of autistic patients on visuospatial tasks requiring local search, like the Embedded Figures Task (EFT). A well-known interpretation of this is "weak central coherence", i.e. autistic patients may show a reduced general ability to process information in its context and may therefore have a tendency to favour local over global aspects of information processing. An alternative view is that the local processing advantage in the EFT may result from a relative amplification of early perceptual processes which boosts processing of local stimulus properties but does not affect processing of global context. This study used functional magnetic resonance imaging (fMRI) in 12 autistic adolescents (9 Asperger and 3 high-functioning autistic patients) and 12 matched controls to help distinguish, on neurophysiological grounds, between these two accounts of EFT performance in autistic patients. Behaviourally, we found autistic individuals to be unimpaired during the EFT while they were significantly worse at performing a closely matched control task with minimal local search requirements. The fMRI results showed that activations specific for the local search aspects of the EFT were left-lateralised in parietal and premotor areas for the control group (as previously demonstrated for adults), whereas for the patients these activations were found in right primary visual cortex and bilateral extrastriate areas. These results suggest that enhanced local processing in early visual areas, as opposed to impaired processing of global context, is characteristic for performance of the EFT by autistic patients.
Neurophysiological correlates of relatively enhanced local visual search in autistic adolescents
Manjaly, Zina M.; Bruning, Nicole; Neufang, Susanne; Stephan, Klaas E.; Brieber, Sarah; Marshall, John C.; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Fink, Gereon R.
2007-01-01
Previous studies found normal or even superior performance of autistic patients on visuospatial tasks requiring local search, like the Embedded Figures Task (EFT). A well-known interpretation of this is “weak central coherence”, i.e. autistic patients may show a reduced general ability to process information in its context and may therefore have a tendency to favour local over global aspects of information processing. An alternative view is that the local processing advantage in the EFT may result from a relative amplification of early perceptual processes which boosts processing of local stimulus properties but does not affect processing of global context. This study used functional magnetic resonance imaging (fMRI) in 12 autistic adolescents (9 Asperger and 3 high-functioning autistic patients) and 12 matched controls to help distinguish, on neurophysiological grounds, between these two accounts of EFT performance in autistic patients. Behaviourally, we found autistic individuals to be unimpaired during the EFT while they were significantly worse at performing a closely matched control task with minimal local search requirements. The fMRI results showed that activations specific for the local search aspects of the EFT were left-lateralised in parietal and premotor areas for the control group (as previously demonstrated for adults), whereas for the patients these activations were found in right primary visual cortex and bilateral extrastriate areas. These results suggest that enhanced local processing in early visual areas, as opposed to impaired processing of global context, is characteristic for performance of the EFT by autistic patients. PMID:17240169
Non-invasive long-term fluorescence live imaging of Tribolium castaneum embryos.
Strobl, Frederic; Stelzer, Ernst H K
2014-06-01
Insect development has contributed significantly to our understanding of metazoan development. However, most information has been obtained by analyzing a single species, the fruit fly Drosophila melanogaster. Embryonic development of the red flour beetle Tribolium castaneum differs fundamentally from that of Drosophila in aspects such as short-germ development, embryonic leg development, extensive extra-embryonic membrane formation and non-involuted head development. Although Tribolium has become the second most important insect model organism, previous live imaging attempts have addressed only specific questions and no long-term live imaging data of Tribolium embryogenesis have been available. By combining light sheet-based fluorescence microscopy with a novel mounting method, we achieved complete, continuous and non-invasive fluorescence live imaging of Tribolium embryogenesis at high spatiotemporal resolution. The embryos survived the 2-day or longer imaging process, developed into adults and produced fertile progeny. Our data document all morphogenetic processes from the rearrangement of the uniform blastoderm to the onset of regular muscular movement in the same embryo and in four orientations, contributing significantly to the understanding of Tribolium development. Furthermore, we created a comprehensive chronological table of Tribolium embryogenesis, integrating most previous work and providing a reference for future studies. Based on our observations, we provide evidence that serosa window closure and serosa opening, although deferred by more than 1 day, are linked. All our long-term imaging datasets are available as a resource for the community. Tribolium is only the second insect species, after Drosophila, for which non-invasive long-term fluorescence live imaging has been achieved. © 2014. Published by The Company of Biologists Ltd.
A portable low-cost long-term live-cell imaging platform for biomedical research and education.
Walzik, Maria P; Vollmar, Verena; Lachnit, Theresa; Dietz, Helmut; Haug, Susanne; Bachmann, Holger; Fath, Moritz; Aschenbrenner, Daniel; Abolpour Mofrad, Sepideh; Friedrich, Oliver; Gilbert, Daniel F
2015-02-15
Time-resolved visualization and analysis of slow dynamic processes in living cells has revolutionized many aspects of in vitro cellular studies. However, existing technology applied to time-resolved live-cell microscopy is often immobile, costly and requires a high level of skill to use and maintain. These factors limit its utility to field research and educational purposes. The recent availability of rapid prototyping technology makes it possible to quickly and easily engineer purpose-built alternatives to conventional research infrastructure which are low-cost and user-friendly. In this paper we describe the prototype of a fully automated low-cost, portable live-cell imaging system for time-resolved label-free visualization of dynamic processes in living cells. The device is light-weight (3.6 kg), small (22 × 22 × 22 cm) and extremely low-cost (<€1250). We demonstrate its potential for biomedical use by long-term imaging of recombinant HEK293 cells at varying culture conditions and validate its ability to generate time-resolved data of high quality allowing for analysis of time-dependent processes in living cells. While this work focuses on long-term imaging of mammalian cells, the presented technology could also be adapted for use with other biological specimen and provides a general example of rapidly prototyped low-cost biosensor technology for application in life sciences and education. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
Methodology for quantitative rapid multi-tracer PET tumor characterizations.
Kadrmas, Dan J; Hoffman, John M
2013-10-04
Positron emission tomography (PET) can image a wide variety of functional and physiological parameters in vivo using different radiotracers. As more is learned about the molecular basis for disease and treatment, the potential value of molecular imaging for characterizing and monitoring disease status has increased. Characterizing multiple aspects of tumor physiology by imaging multiple PET tracers in a single patient provides additional complementary information, and there is a significant body of literature supporting the potential value of multi-tracer PET imaging in oncology. However, imaging multiple PET tracers in a single patient presents a number of challenges. A number of techniques are under development for rapidly imaging multiple PET tracers in a single scan, where signal-recovery processing algorithms are employed to recover various imaging endpoints for each tracer. Dynamic imaging is generally used with tracer injections staggered in time, and kinetic constraints are utilized to estimate each tracers' contribution to the multi-tracer imaging signal. This article summarizes past and ongoing work in multi-tracer PET tumor imaging, and then organizes and describes the main algorithmic approaches for achieving multi-tracer PET signal-recovery. While significant advances have been made, the complexity of the approach necessitates protocol design, optimization, and testing for each particular tracer combination and application. Rapid multi-tracer PET techniques have great potential for both research and clinical cancer imaging applications, and continued research in this area is warranted.
Methodology for Quantitative Rapid Multi-Tracer PET Tumor Characterizations
Kadrmas, Dan J.; Hoffman, John M.
2013-01-01
Positron emission tomography (PET) can image a wide variety of functional and physiological parameters in vivo using different radiotracers. As more is learned about the molecular basis for disease and treatment, the potential value of molecular imaging for characterizing and monitoring disease status has increased. Characterizing multiple aspects of tumor physiology by imaging multiple PET tracers in a single patient provides additional complementary information, and there is a significant body of literature supporting the potential value of multi-tracer PET imaging in oncology. However, imaging multiple PET tracers in a single patient presents a number of challenges. A number of techniques are under development for rapidly imaging multiple PET tracers in a single scan, where signal-recovery processing algorithms are employed to recover various imaging endpoints for each tracer. Dynamic imaging is generally used with tracer injections staggered in time, and kinetic constraints are utilized to estimate each tracers' contribution to the multi-tracer imaging signal. This article summarizes past and ongoing work in multi-tracer PET tumor imaging, and then organizes and describes the main algorithmic approaches for achieving multi-tracer PET signal-recovery. While significant advances have been made, the complexity of the approach necessitates protocol design, optimization, and testing for each particular tracer combination and application. Rapid multi-tracer PET techniques have great potential for both research and clinical cancer imaging applications, and continued research in this area is warranted. PMID:24312149
Moriya, Jun
2017-01-01
According to cognitive theories, verbal processing attenuates emotional processing, whereas visual imagery enhances emotional processing and contributes to the maintenance of social anxiety. Individuals with social anxiety report negative mental images in social situations. However, the general ability of visual mental imagery of neutral scenes in individuals with social anxiety is still unclear. The present study investigated the general ability of non-emotional mental imagery (vividness, preferences for imagery vs. verbal processing, and object or spatial imagery) and the moderating role of effortful control in attenuating social anxiety. The participants ( N = 231) completed five questionnaires. The results showed that social anxiety was not necessarily associated with all aspects of mental imagery. As suggested by theories, social anxiety was not associated with a preference for verbal processing. However, social anxiety was positively correlated with the visual imagery scale, especially the object imagery scale, which concerns the ability to construct pictorial images of individual objects. Further, it was negatively correlated with the spatial imagery scale, which concerns the ability to process information about spatial relations between objects. Although object imagery and spatial imagery positively and negatively predicted the degree of social anxiety, respectively, these effects were attenuated when socially anxious individuals had high effortful control. Specifically, in individuals with high effortful control, both object and spatial imagery were not associated with social anxiety. Socially anxious individuals might prefer to construct pictorial images of individual objects in natural scenes through object imagery. However, even in individuals who exhibit these features of mental imagery, effortful control could inhibit the increase in social anxiety.
Aakre, Kenneth T; Valley, Timothy B; O'Connor, Michael K
2010-03-01
Lean Six Sigma process improvement methodologies have been used in manufacturing for some time. However, Lean Six Sigma process improvement methodologies also are applicable to radiology as a way to identify opportunities for improvement in patient care delivery settings. A multidisciplinary team of physicians and staff conducted a 100-day quality improvement project with the guidance of a quality advisor. By using the framework of DMAIC (define, measure, analyze, improve, and control), time studies were performed for all aspects of patient and technologist involvement. From these studies, value stream maps for the current state and for the future were developed, and tests of change were implemented. Comprehensive value stream maps showed that before implementation of process changes, an average time of 20.95 minutes was required for completion of a bone densitometry study. Two process changes (ie, tests of change) were undertaken. First, the location for completion of a patient assessment form was moved from inside the imaging room to the waiting area, enabling patients to complete the form while waiting for the technologist. Second, the patient was instructed to sit in a waiting area immediately outside the imaging rooms, rather than in the main reception area, which is far removed from the imaging area. Realignment of these process steps, with reduced technologist travel distances, resulted in a 3-minute average decrease in the patient cycle time. This represented a 15% reduction in the initial patient cycle time with no change in staff or costs. Radiology process improvement projects can yield positive results despite small incremental changes.
Fujino, Junya; Tei, Shisei; Jankowski, Kathryn F; Kawada, Ryosaku; Murai, Toshiya; Takahashi, Hidehiko
2017-12-26
We are constantly exposed to socially conflicting situations in everyday life, and cognitive flexibility is essential for adaptively coping with such difficulties. Flexible goal choice and pursuit are not exclusively conscious, and therefore cognitive flexibility involves both explicit and implicit forms of processing. However, it is unclear how individual differences in explicit and implicit aspects of flexibility are associated with neural activity in a resting state. Here, we measured intrinsic fractional amplitude of low-frequency fluctuations (fALFF) by resting-state functional magnetic resonance imaging (RS-fMRI) as an indicator of regional brain spontaneous activity, together with explicit and implicit aspects of cognitive flexibility using the Cognitive Flexibility Scale (CFS) and Implicit Association Test (IAT). Consistent with the dual processing theory, there was a strong association between explicit aspects of flexibility (CFS score) and "rationalism" thinking style and between implicit aspects (IAT effect) and "experientialism." The level of explicit flexibility was also correlated with fALFF values in the left lateral prefrontal cortex, whereas the level of implicit flexibility was correlated with fALFF values in the right cerebellum. Furthermore, the fALFF values in both regions predicted individual preference for flexible decision-making strategy in a vignettes simulation task. These results add to our understanding of the neural mechanisms underlying flexible decision-making for solving social conflicts. More generally, our findings highlight the utility of RS-fMRI combined with both explicit and implicit psychometric measures for better understanding individual differences in social cognition. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Some Aspects in Photogrammetry Education at the Department of Geodesy and Cadastre of the VGTU
NASA Astrophysics Data System (ADS)
Ruzgienė, Birutė
2008-03-01
The education in photogrammetry is very important when applying photogrammetric methods for the terrain mapping purposes, for spatial data modelling, solving engineering tasks, measuring of architectural monuments etc. During the time the traditional photogrammetric technologies have been changing to modern fully digital photogrammetric workflow. The number of potential users of the photogrammetric methods tends to increase, because of high-degree automation in photographs (images) processing. The main subjects in Photogrammetry (particularly in Digital Photogrammetry) educational process are discussed. Different methods and digital systems are demonstrated with the examples of aerial photogrammetry products. The main objective is to search the possibilities for training in the photogrammetric measurements. Special attention is paid to the stereo plotting from aerial photography applying modified for teaching analytical technology. The integration of functionality of Digital Photogrammetric Systems and Digital Image Processing is analysed as well with an intention of extending the application areas and possibilities for usage of modern technologies in urban mapping and land cadastre. The practical presentation of photos geometry restitution is implemented as significant part of the studies. The interactive teaching for main photogrammetric procedures and controlling systems are highly desirable that without any doubt improve the quality of educational process.
Synthesis, isolation and purification of [11C]-choline
Jadwiński, Michał; Chmura, Agnieszka; Gorczewski, Kamil; Sokół, Maria
2016-01-01
[11C]-choline is an effective PET tracer used for imaging of neoplastic lesions and metastases of the prostate cancer. However, its production can be a challenge for manufacturers, as it has not yet been described in Polish or European pharmacopoeia. In this study the technical aspects of [11C]-choline production are described and detailed process parameters are provided. The quality control procedures for releasing [11C]-choline as solutio iniectabilis are also presented. The purity and quality of the radiopharmaceutical obtained according to the proposed method were find to be high enough to safely administrate the radiopharmaceutical to patients. Application of an automated synthesizer makes it possible to carry out the entire process of [11C]-choline production, isolation and purification within 20 minutes. It is crucial to maintain all aspects of the process as short as possible, since the decay half-time of carbon-11 is 20.4 minutes. The resulting radiopharmaceutical is sterile and pyrogen-free and of a high chemical, radiochemical, and radionuclide purity proved by chromatographic techniques. The yield of the process is up to 20%. [11C]-choline PET scanning can be used as accurate and effective diagnostic tool in all centers equipped with [11C]-target containing cyclotron. PMID:27660552
A diabetic retinopathy detection method using an improved pillar K-means algorithm.
Gogula, Susmitha Valli; Divakar, Ch; Satyanarayana, Ch; Rao, Allam Appa
2014-01-01
The paper presents a new approach for medical image segmentation. Exudates are a visible sign of diabetic retinopathy that is the major reason of vision loss in patients with diabetes. If the exudates extend into the macular area, blindness may occur. Automated detection of exudates will assist ophthalmologists in early diagnosis. This segmentation process includes a new mechanism for clustering the elements of high-resolution images in order to improve precision and reduce computation time. The system applies K-means clustering to the image segmentation after getting optimized by Pillar algorithm; pillars are constructed in such a way that they can withstand the pressure. Improved pillar algorithm can optimize the K-means clustering for image segmentation in aspects of precision and computation time. This evaluates the proposed approach for image segmentation by comparing with Kmeans and Fuzzy C-means in a medical image. Using this method, identification of dark spot in the retina becomes easier and the proposed algorithm is applied on diabetic retinal images of all stages to identify hard and soft exudates, where the existing pillar K-means is more appropriate for brain MRI images. This proposed system help the doctors to identify the problem in the early stage and can suggest a better drug for preventing further retinal damage.
NASA Astrophysics Data System (ADS)
Mazza, F.; Da Silva, M. P.; Le Callet, P.; Heynderickx, I. E. J.
2015-03-01
Multimedia quality assessment has been an important research topic during the last decades. The original focus on artifact visibility has been extended during the years to aspects as image aesthetics, interestingness and memorability. More recently, Fedorovskaya proposed the concept of 'image psychology': this concept focuses on additional quality dimensions related to human content processing. While these additional dimensions are very valuable in understanding preferences, it is very hard to define, isolate and measure their effect on quality. In this paper we continue our research on face pictures investigating which image factors influence context perception. We collected perceived fit of a set of images to various content categories. These categories were selected based on current typologies in social networks. Logistic regression was adopted to model category fit based on images features. In this model we used both low level and high level features, the latter focusing on complex features related to image content. In order to extract these high level features, we relied on crowdsourcing, since computer vision algorithms are not yet sufficiently accurate for the features we needed. Our results underline the importance of some high level content features, e.g. the dress of the portrayed person and scene setting, in categorizing image.
On-the-fly detection of images with gastritis aspects in magnetically guided capsule endoscopy
NASA Astrophysics Data System (ADS)
Mewes, P. W.; Neumann, D.; Juloski, A. L.; Angelopoulou, E.; Hornegger, J.
2011-03-01
Capsule Endoscopy (CE) was introduced in 2000 and has since become an established diagnostic procedure for the small bowel, colon and esophagus. For the CE examination the patient swallows the capsule, which then travels through the gastrointestinal tract under the influence of the peristaltic movements. CE is not indicated for stomach examination, as the capsule movements can not be controlled from the outside and the entire surface of the stomach can not be reliably covered. Magnetically-guided capsule endoscopy (MGCE) was introduced in 2010. For the MGCE procedure the stomach is filled with water and the capsule is navigated from the outside using an external magnetic field. During the examination the operator can control the motion of the capsule in order to obtain a sufficient number of stomach-surface images with diagnostic value. The quality of the examination depends on the skill of the operator and his ability to detect aspects of interest in real time. We present a novel computer-assisted diagnostic-procedure (CADP) algorithm for indicating gastritis pathologies in the stomach during the examination. Our algorithm is based on pre-processing methods and feature vectors that are suitably chosen for the challenges of the MGCE imaging (suspended particles, bubbles, lighting). An image is classified using an ada-boost trained classifier. For the classifier training, a number of possible features were investigated. Statistical evaluation was conducted to identify relevant features with discriminative potential. The proposed algorithm was tested on 12 video sequences stemming from 6 volunteers. A mean detection rate of 91.17% was achieved during leave-one out cross-validation.
Intelligent Image Based Computer Aided Education (IICAE)
NASA Astrophysics Data System (ADS)
David, Amos A.; Thiery, Odile; Crehange, Marion
1989-03-01
Artificial Intelligence (AI) has found its way into Computer Aided Education (CAE), and there are several systems constructed to put in evidence its interesting advantages. We believe that images (graphic or real) play an important role in learning. However, the use of images, outside their use as illustration, makes it necessary to have applications such as AI. We shall develop the application of AI in an image based CAE and briefly present the system under construction to put in evidence our concept. We shall also elaborate a methodology for constructing such a system. Futhermore we shall briefly present the pedagogical and psychological activities in a learning process. Under the pedagogical and psychological aspect of learning, we shall develop areas such as the importance of image in learning both as pedagogical objects as well as means for obtaining psychological information about the learner. We shall develop the learner's model, its use, what to build into it and how. Under the application of AI in an image based CAE, we shall develop the importance of AI in exploiting the knowledge base in the learning environment and its application as a means of implementing pedagogical strategies.
Geldermann, Ina; Grouls, Christoph; Kuhl, Christiane; Deserno, Thomas M; Spreckelsen, Cord
2013-08-01
Usability aspects of different integration concepts for picture archiving and communication systems (PACS) and computer-aided diagnosis (CAD) were inquired on the example of BoneXpert, a program determining the skeletal age from a left hand's radiograph. CAD-PACS integration was assessed according to its levels: data, function, presentation, and context integration focusing on usability aspects. A user-based study design was selected. Statements of seven experienced radiologists using two alternative types of integration provided by BoneXpert were acquired and analyzed using a mixed-methods approach based on think-aloud records and a questionnaire. In both variants, the CAD module (BoneXpert) was easily integrated in the workflow, found comprehensible and fitting in the conceptual framework of the radiologists. Weak points of the software integration referred to data and context integration. Surprisingly, visualization of intermediate image processing states (presentation integration) was found less important as compared to efficient handling and fast computation. Seamlessly integrating CAD into the PACS without additional work steps or unnecessary interrupts and without visualizing intermediate images may considerably improve software performance and user acceptance with efforts in time.
Publication ethics in biomedical journals from countries in Central and Eastern Europe.
Broga, Mindaugas; Mijaljica, Goran; Waligora, Marcin; Keis, Aime; Marusic, Ana
2014-03-01
Publication ethics is an important aspect of both the research and publication enterprises. It is particularly important in the field of biomedical science because published data may directly affect human health. In this article, we examine publication ethics policies in biomedical journals published in Central and Eastern Europe. We were interested in possible differences between East European countries that are members of the European Union (Eastern EU) and South-East European countries (South-East Europe) that are not members of the European Union. The most common ethical issues addressed by all journals in the region were redundant publication, peer review process, and copyright or licensing details. Image manipulation, editors' conflicts of interest and registration of clinical trials were the least common ethical policies. Three aspects were significantly more common in journals published outside the EU: statements on the endorsement of international editorial standards, contributorship policy, and image manipulation. On the other hand, copyright or licensing information were more prevalent in journals published in the Eastern EU. The existence of significant differences among biomedical journals' ethical policies calls for further research and active measures to harmonize policies across journals.
Face Adaptation Effects: Reviewing the Impact of Adapting Information, Time, and Transfer
Strobach, Tilo; Carbon, Claus-Christian
2013-01-01
The ability to adapt is essential to live and survive in an ever-changing environment such as the human ecosystem. Here we review the literature on adaptation effects of face stimuli to give an overview of existing findings in this area, highlight gaps in its research literature, initiate new directions in face adaptation research, and help to design future adaptation studies. Furthermore, this review should lead to better understanding of the processing characteristics as well as the mental representations of face-relevant information. The review systematizes studies at a behavioral level in respect of a framework which includes three dimensions representing the major characteristics of studies in this field of research. These dimensions comprise (1) the specificity of adapting face information, e.g., identity, gender, or age aspects of the material to be adapted to (2) aspects of timing (e.g., the sustainability of adaptation effects) and (3) transfer relations between face images presented during adaptation and adaptation tests (e.g., images of the same or different identities). The review concludes with options for how to combine findings across different dimensions to demonstrate the relevance of our framework for future studies. PMID:23760550
An efficient system for reliably transmitting image and video data over low bit rate noisy channels
NASA Technical Reports Server (NTRS)
Costello, Daniel J., Jr.; Huang, Y. F.; Stevenson, Robert L.
1994-01-01
This research project is intended to develop an efficient system for reliably transmitting image and video data over low bit rate noisy channels. The basic ideas behind the proposed approach are the following: employ statistical-based image modeling to facilitate pre- and post-processing and error detection, use spare redundancy that the source compression did not remove to add robustness, and implement coded modulation to improve bandwidth efficiency and noise rejection. Over the last six months, progress has been made on various aspects of the project. Through our studies of the integrated system, a list-based iterative Trellis decoder has been developed. The decoder accepts feedback from a post-processor which can detect channel errors in the reconstructed image. The error detection is based on the Huber Markov random field image model for the compressed image. The compression scheme used here is that of JPEG (Joint Photographic Experts Group). Experiments were performed and the results are quite encouraging. The principal ideas here are extendable to other compression techniques. In addition, research was also performed on unequal error protection channel coding, subband vector quantization as a means of source coding, and post processing for reducing coding artifacts. Our studies on unequal error protection (UEP) coding for image transmission focused on examining the properties of the UEP capabilities of convolutional codes. The investigation of subband vector quantization employed a wavelet transform with special emphasis on exploiting interband redundancy. The outcome of this investigation included the development of three algorithms for subband vector quantization. The reduction of transform coding artifacts was studied with the aid of a non-Gaussian Markov random field model. This results in improved image decompression. These studies are summarized and the technical papers included in the appendices.
Nguyen, Peter L.; Davidson, Bennett; Akkina, Sanjeev; Guzman, Grace; Setty, Suman; Kajdacsy-Balla, Andre; Walsh, Michael J.
2015-01-01
High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging is an emerging approach to obtain detailed images that have associated biochemical information. FT-IR imaging of tissue is based on the principle that different regions of the mid-infrared are absorbed by different chemical bonds (e.g., C=O, C-H, N-H) within cells or tissue that can then be related to the presence and composition of biomolecules (e.g., lipids, DNA, glycogen, protein, collagen). In an FT-IR image, every pixel within the image comprises an entire Infrared (IR) spectrum that can give information on the biochemical status of the cells that can then be exploited for cell-type or disease-type classification. In this paper, we show: how to obtain IR images from human tissues using an FT-IR system, how to modify existing instrumentation to allow for high-definition imaging capabilities, and how to visualize FT-IR images. We then present some applications of FT-IR for pathology using the liver and kidney as examples. FT-IR imaging holds exciting applications in providing a novel route to obtain biochemical information from cells and tissue in an entirely label-free non-perturbing route towards giving new insight into biomolecular changes as part of disease processes. Additionally, this biochemical information can potentially allow for objective and automated analysis of certain aspects of disease diagnosis. PMID:25650759
IT infrastructure in the era of imaging 3.0.
McGinty, Geraldine B; Allen, Bibb; Geis, J Raymond; Wald, Christoph
2014-12-01
Imaging 3.0 is a blueprint for the future of radiology modeled after the description of Web 3.0 as "more connected, more open, and more intelligent." Imaging 3.0 involves radiologists' using their expertise to manage all aspects of imaging care to improve patient safety and outcomes and to deliver high-value care. IT tools are critical elements and drivers of success as radiologists embrace the concepts of Imaging 3.0. Organized radiology, specifically the ACR, is the natural convener and resource for the development of this Imaging 3.0 toolkit. The ACR's new Imaging 3.0 Informatics Committee is actively working to develop the informatics tools radiologists need to improve efficiency, deliver more value, and provide quantitative ways to demonstrate their value in new health care delivery and payment systems. This article takes each step of the process of delivering high-value Imaging 3.0 care and outlines the tools available as well as additional resources available to support practicing radiologists. From the moment when imaging is considered through the delivery of a meaningful and actionable report that is communicated to the referring clinician and, when appropriate, to the patient, Imaging 3.0 IT tools will enable radiologists to position themselves as vital constituents in cost-effective, high-value health care. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights reserved.
Building an Authentic Leadership Image
ERIC Educational Resources Information Center
Criswell, Corey; Campbell, David
2008-01-01
Your image can be either an asset or a liability for you as a leader. Image building is neither superficial nor unimportant. It's not about creating a false image, but recognizing genuine aspects of yourself that should be coming across to other people--but aren't. Crafting your image requires you to gain a clear picture of the image people are…
Going fully digital: Perspective of a Dutch academic pathology lab
Stathonikos, Nikolas; Veta, Mitko; Huisman, André; van Diest, Paul J.
2013-01-01
During the last years, whole slide imaging has become more affordable and widely accepted in pathology labs. Digital slides are increasingly being used for digital archiving of routinely produced clinical slides, remote consultation and tumor boards, and quantitative image analysis for research purposes and in education. However, the implementation of a fully digital Pathology Department requires an in depth look into the suitability of digital slides for routine clinical use (the image quality of the produced digital slides and the factors that affect it) and the required infrastructure to support such use (the storage requirements and integration with lab management and hospital information systems). Optimization of digital pathology workflow requires communication between several systems, which can be facilitated by the use of open standards for digital slide storage and scanner management. Consideration of these aspects along with appropriate validation of the use of digital slides for routine pathology can pave the way for pathology departments to go “fully digital.” In this paper, we summarize our experiences so far in the process of implementing a fully digital workflow at our Pathology Department and the steps that are needed to complete this process. PMID:23858390
Li, Yixian; Qi, Lehua; Song, Yongshan; Chao, Xujiang
2017-06-01
The components of carbon/carbon (C/C) composites have significant influence on the thermal and mechanical properties, so a quantitative characterization of component is necessary to study the microstructure of C/C composites, and further to improve the macroscopic properties of C/C composites. Considering the extinction crosses of the pyrocarbon matrix have significant moving features, the polarized light microscope (PLM) video is used to characterize C/C composites quantitatively because it contains sufficiently dynamic and structure information. Then the optical flow method is introduced to compute the optical flow field between the adjacent frames, and segment the components of C/C composites from PLM image by image processing. Meanwhile the matrix with different textures is re-segmented by the length difference of motion vectors, and then the component fraction of each component and extinction angle of pyrocarbon matrix are calculated directly. Finally, the C/C composites are successfully characterized from three aspects of carbon fiber, pyrocarbon, and pores by a series of image processing operators based on PLM video, and the errors of component fractions are less than 15%. © 2017 Wiley Periodicals, Inc.
Flight Performance of the HEROES Solar Aspect System
NASA Astrophysics Data System (ADS)
Shih, Albert Y.; Christe, Steven; Rodriguez, Marcello; Gregory, Kyle; Cramer, Alexander; Edgerton, Melissa; Gaskin, Jessica; O'Connor, Brian; Sobey, Alexander
2014-06-01
Hard X-ray (HXR) observations of solar flares reveal the signatures of energetic electrons, and HXR images with high dynamic range and high sensitivity can distinguish between where electrons are accelerated and where they stop. Furthermore, high-sensitivity HXR measurements may be able to detect the presence of electron acceleration in the non-flaring corona. The High Energy Replicated Optics to Explore the Sun (HEROES) balloon mission added the capability of solar observations to an existing astrophysics balloon payload, HERO, which used grazing-incidence optics for direct HXR imaging. The HEROES Solar Aspect System (SAS) was developed and built to provide pointing knowledge during solar observations to better than the ~20 arcsec FWHM angular resolution of the HXR instrument. The SAS consists of two separate systems: the Pitch-Yaw aspect System (PYAS) and the Roll Aspect System (RAS). The PYAS compares the position of an optical image of the Sun relative to precise fiducials to determine the pitch and yaw pointing offsets from the desired solar target. The RAS images the Earth's horizon in opposite directions simultaneously to determine the roll of the gondola. HEROES launched in September 2013 from Fort Sumner, New Mexico, and had a successful one-day flight. We present the detailed analysis of the performance of the SAS for that flight.
High-performance floating-point image computing workstation for medical applications
NASA Astrophysics Data System (ADS)
Mills, Karl S.; Wong, Gilman K.; Kim, Yongmin
1990-07-01
The medical imaging field relies increasingly on imaging and graphics techniques in diverse applications with needs similar to (or more stringent than) those of the military, industrial and scientific communities. However, most image processing and graphics systems available for use in medical imaging today are either expensive, specialized, or in most cases both. High performance imaging and graphics workstations which can provide real-time results for a number of applications, while maintaining affordability and flexibility, can facilitate the application of digital image computing techniques in many different areas. This paper describes the hardware and software architecture of a medium-cost floating-point image processing and display subsystem for the NeXT computer, and its applications as a medical imaging workstation. Medical imaging applications of the workstation include use in a Picture Archiving and Communications System (PACS), in multimodal image processing and 3-D graphics workstation for a broad range of imaging modalities, and as an electronic alternator utilizing its multiple monitor display capability and large and fast frame buffer. The subsystem provides a 2048 x 2048 x 32-bit frame buffer (16 Mbytes of image storage) and supports both 8-bit gray scale and 32-bit true color images. When used to display 8-bit gray scale images, up to four different 256-color palettes may be used for each of four 2K x 2K x 8-bit image frames. Three of these image frames can be used simultaneously to provide pixel selectable region of interest display. A 1280 x 1024 pixel screen with 1: 1 aspect ratio can be windowed into the frame buffer for display of any portion of the processed image or images. In addition, the system provides hardware support for integer zoom and an 82-color cursor. This subsystem is implemented on an add-in board occupying a single slot in the NeXT computer. Up to three boards may be added to the NeXT for multiple display capability (e.g., three 1280 x 1024 monitors, each with a 16-Mbyte frame buffer). Each add-in board provides an expansion connector to which an optional image computing coprocessor board may be added. Each coprocessor board supports up to four processors for a peak performance of 160 MFLOPS. The coprocessors can execute programs from external high-speed microcode memory as well as built-in internal microcode routines. The internal microcode routines provide support for 2-D and 3-D graphics operations, matrix and vector arithmetic, and image processing in integer, IEEE single-precision floating point, or IEEE double-precision floating point. In addition to providing a library of C functions which links the NeXT computer to the add-in board and supports its various operational modes, algorithms and medical imaging application programs are being developed and implemented for image display and enhancement. As an extension to the built-in algorithms of the coprocessors, 2-D Fast Fourier Transform (FF1), 2-D Inverse FFF, convolution, warping and other algorithms (e.g., Discrete Cosine Transform) which exploit the parallel architecture of the coprocessor board are being implemented.
Doughty, Benjamin; Simpson, Mary Jane; Yang, Bin; ...
2016-02-16
Our work aims to simplify multi-dimensional femtosecond transient absorption microscopy (TAM) data into decay associated amplitude maps that describe the spatial distributions of dynamical processes occurring on various characteristic timescales. Application of this method to TAM data obtained from a model methyl-ammonium lead iodide (CH 3NH 3PbI 3) perovskite thin film allows us to simplify the dataset consisting of a 68 time-resolved images into 4 decay associated amplitude maps. Furthermore, these maps provide a simple means to visualize the complex electronic excited-state dynamics in this system by separating distinct dynamical processes evolving on characteristic timescales into individual spatial images. Thismore » approach provides new insight into subtle aspects of ultrafast relaxation dynamics associated with excitons and charge carriers in the perovskite thin film, which have recently been found to coexist at spatially distinct locations.« less
Sustainable Land Imaging User Requirements
NASA Astrophysics Data System (ADS)
Wu, Z.; Snyder, G.; Vadnais, C. M.
2017-12-01
The US Geological Survey (USGS) Land Remote Sensing Program (LRSP) has collected user requirements from a range of applications to help formulate the Landsat 9 follow-on mission (Landsat 10) through the Requirements, Capabilities and Analysis (RCA) activity. The USGS is working with NASA to develop Landsat 10, which is scheduled to launch in the 2027 timeframe as part of the Sustainable Land Imaging program. User requirements collected through RCA will help inform future Landsat 10 sensor designs and mission characteristics. Current Federal civil community users have provided hundreds of requirements through systematic, in-depth interviews. Academic, State, local, industry, and international Landsat user community input was also incorporated in the process. Emphasis was placed on spatial resolution, temporal revisit, and spectral characteristics, as well as other aspects such as accuracy, continuity, sampling condition, data access and format. We will provide an overview of the Landsat 10 user requirements collection process and summary results of user needs from the broad land imagining community.
Interpretation of Pennsylvania agricultural land use from ERTS-1 data
NASA Technical Reports Server (NTRS)
Mcmurtry, G. J.; Petersen, G. W. (Principal Investigator); Wilson, A. D.
1974-01-01
The author has identified the following significant results. To study the complex agricultural patterns in Pennsylvania, a portion of an ERTS scene was selected for detailed analysis. Various photographic products were made and were found to be only of limited value. This necessitated the digital processing of the ERTS data. Using an unsupervised classification procedure, it was possible to delineate the following categories: (1) forest land with a northern aspect, (2) forest land with a southern aspect, (3) valley trees, (4) wheat, (5) corn, (6) alfalfa, grass, pasture, (7) disturbed land, (8) builtup land, (9) strip mines, and (10) water. These land use categories were delineated at a scale of approximately 1:20,000 on the line printer output. Land use delineations were also made using the General Electric IMAGE 100 interactive analysis system.
Ultrasonic imaging of material flaws exploiting multipath information
NASA Astrophysics Data System (ADS)
Shen, Xizhong; Zhang, Yimin D.; Demirli, Ramazan; Amin, Moeness G.
2011-05-01
In this paper, we consider ultrasonic imaging for the visualization of flaws in a material. Ultrasonic imaging is a powerful nondestructive testing (NDT) tool which assesses material conditions via the detection, localization, and classification of flaws inside a structure. Multipath exploitations provide extended virtual array apertures and, in turn, enhance imaging capability beyond the limitation of traditional multisensor approaches. We utilize reflections of ultrasonic signals which occur when encountering different media and interior discontinuities. The waveforms observed at the physical as well as virtual sensors yield additional measurements corresponding to different aspect angles. Exploitation of multipath information addresses unique issues observed in ultrasonic imaging. (1) Utilization of physical and virtual sensors significantly extends the array aperture for image enhancement. (2) Multipath signals extend the angle of view of the narrow beamwidth of the ultrasound transducers, allowing improved visibility and array design flexibility. (3) Ultrasonic signals experience difficulty in penetrating a flaw, thus the aspect angle of the observation is limited unless access to other sides is available. The significant extension of the aperture makes it possible to yield flaw observation from multiple aspect angles. We show that data fusion of physical and virtual sensor data significantly improves the detection and localization performance. The effectiveness of the proposed multipath exploitation approach is demonstrated through experimental studies.
Image-guided tumor ablation: standardization of terminology and reporting criteria.
Goldberg, S Nahum; Grassi, Clement J; Cardella, John F; Charboneau, J William; Dodd, Gerald D; Dupuy, Damian E; Gervais, Debra A; Gillams, Alice R; Kane, Robert A; Lee, Fred T; Livraghi, Tito; McGahan, John; Phillips, David A; Rhim, Hyunchul; Silverman, Stuart G; Solbiati, Luigi; Vogl, Thomas J; Wood, Bradford J; Vedantham, Suresh; Sacks, David
2009-07-01
The field of interventional oncology with use of image-guided tumor ablation requires standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison between treatments that use different technologies, such as chemical (ethanol or acetic acid) ablation, and thermal therapies, such as radiofrequency (RF), laser, microwave, ultrasound, and cryoablation. This document provides a framework that will hopefully facilitate the clearest communication between investigators and will provide the greatest flexibility in comparison between the many new, exciting, and emerging technologies. An appropriate vehicle for reporting the various aspects of image-guided ablation therapy, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings, are outlined. Methods for standardizing the reporting of follow-up findings and complications and other important aspects that require attention when reporting clinical results are addressed. It is the group's intention that adherence to the recommendations will facilitate achievement of the group's main objective: improved precision and communication in this field that lead to more accurate comparison of technologies and results and, ultimately, to improved patient outcomes. The intent of this standardization of terminology is to provide an appropriate vehicle for reporting the various aspects of image-guided ablation therapy.
Real-time high-level video understanding using data warehouse
NASA Astrophysics Data System (ADS)
Lienard, Bruno; Desurmont, Xavier; Barrie, Bertrand; Delaigle, Jean-Francois
2006-02-01
High-level Video content analysis such as video-surveillance is often limited by computational aspects of automatic image understanding, i.e. it requires huge computing resources for reasoning processes like categorization and huge amount of data to represent knowledge of objects, scenarios and other models. This article explains how to design and develop a "near real-time adaptive image datamart", used, as a decisional support system for vision algorithms, and then as a mass storage system. Using RDF specification as storing format of vision algorithms meta-data, we can optimise the data warehouse concepts for video analysis, add some processes able to adapt the current model and pre-process data to speed-up queries. In this way, when new data is sent from a sensor to the data warehouse for long term storage, using remote procedure call embedded in object-oriented interfaces to simplified queries, they are processed and in memory data-model is updated. After some processing, possible interpretations of this data can be returned back to the sensor. To demonstrate this new approach, we will present typical scenarios applied to this architecture such as people tracking and events detection in a multi-camera network. Finally we will show how this system becomes a high-semantic data container for external data-mining.
Biomedical signal and image processing.
Cerutti, Sergio; Baselli, Giuseppe; Bianchi, Anna; Caiani, Enrico; Contini, Davide; Cubeddu, Rinaldo; Dercole, Fabio; Rienzo, Luca; Liberati, Diego; Mainardi, Luca; Ravazzani, Paolo; Rinaldi, Sergio; Signorini, Maria; Torricelli, Alessandro
2011-01-01
Generally, physiological modeling and biomedical signal processing constitute two important paradigms of biomedical engineering (BME): their fundamental concepts are taught starting from undergraduate studies and are more completely dealt with in the last years of graduate curricula, as well as in Ph.D. courses. Traditionally, these two cultural aspects were separated, with the first one more oriented to physiological issues and how to model them and the second one more dedicated to the development of processing tools or algorithms to enhance useful information from clinical data. A practical consequence was that those who did models did not do signal processing and vice versa. However, in recent years,the need for closer integration between signal processing and modeling of the relevant biological systems emerged very clearly [1], [2]. This is not only true for training purposes(i.e., to properly prepare the new professional members of BME) but also for the development of newly conceived research projects in which the integration between biomedical signal and image processing (BSIP) and modeling plays a crucial role. Just to give simple examples, topics such as brain–computer machine or interfaces,neuroengineering, nonlinear dynamical analysis of the cardiovascular (CV) system,integration of sensory-motor characteristics aimed at the building of advanced prostheses and rehabilitation tools, and wearable devices for vital sign monitoring and others do require an intelligent fusion of modeling and signal processing competences that are certainly peculiar of our discipline of BME.
Suggate, Sebastian; Stoeger, Heidrun
2017-10-01
Research suggests that fine motor skills (FMS) are linked to aspects of cognitive development in children. Additionally, lexical processing advantages exist for words implying a high body-object interaction (BOI), with initial findings indicating that such words in turn link to children's FMS-for which we propose and evaluate four competing hypotheses. First, a maturational account argues that any links between FMS and lexical processing should not exist once developmental variables are controlled for. Second, functionalism posits that any link between FMS and lexical processing arises due to environmental interactions. Third, the semantic richness hypothesis argues that sensorimotor input improves lexical processing, but predicts no links between FMS and lexical processing. A fourth account, the nimble-hands, nimble minds (NHNM) hypothesis, proposes that having greater FMS improves lexical processing for high-BOI words. In two experiments, the response latencies of preschool children (n = 90, n = 76, ages = 5;1) to 45 lexical items encompassing high-BOI, low-BOI, and less imageable words were measured, alongside measures of FMS, reasoning, and general receptive/expressive vocabulary. High-BOI words appeared to show unique links to FMS, which remained after accounting for low-BOI and less imageable words, general vocabulary, reasoning, and chronological age. Although further work is needed, the findings provide initial support for the NHNM hypothesis.
Measuring the significance of pearlescence in real-time bottle forming
NASA Astrophysics Data System (ADS)
Nixon, J.; Menary, G.; Yan, S.
2018-05-01
This work examines the optical properties of polyethylene terephthalate (PET) bottles during the stretch-blow-moulding (SBM) process. PET has a relatively large process window with regards to process parameters, however if the boundaries are pushed, the resultant bottle can become insufficient for consumer requirements. One aspect of this process is the onset of pearlescence in the bottle material, where the bottle becomes opaque due to elevated stress whitening. Experimental trials were carried out using a modified free-stretch-blow machine where the deforming bottle was examined in free air. The strain values of the deformation were measured using digital image correlation (DIC) and the optical properties were measured relative to the initial amorphous PET preform. The results reveal that process parameters can significantly affect pearlescence. The detrimental level of pearlescence may be predicted therefore reducing the probability of poorly formed bottles.
Dispersal of Volcanic Ash on Mars: Ash Grain Shape Analysis
NASA Astrophysics Data System (ADS)
Langdalen, Z.; Fagents, S. A.; Fitch, E. P.
2017-12-01
Many ash dispersal models use spheres as ash-grain analogs in drag calculations. These simplifications introduce inaccuracies in the treatment of drag coefficients, leading to inaccurate settling velocities and dispersal predictions. Therefore, we are investigating the use of a range of shape parameters, calculated using grain dimensions, to derive a better representation of grain shape and effective grain cross-sectional area. Specifically, our goal is to apply our results to the modeling of ash deposition to investigate the proposed volcanic origin of certain fine-grained deposits on Mars. Therefore, we are documenting the dimensions and shapes of ash grains from terrestrial subplinian to plinian deposits, in eight size divisions from 2 mm to 16 μm, employing a high resolution optical microscope. The optical image capture protocol provides an accurate ash grain outline by taking multiple images at different focus heights prior to combining them into a composite image. Image composite mosaics are then processed through ImageJ, a robust scientific measurement software package, to calculate a range of dimensionless shape parameters. Since ash grains rotate as they fall, drag forces act on a changing cross-sectional area. Therefore, we capture images and calculate shape parameters of each grain positioned in three orthogonal orientations. We find that the difference between maximum and minimum aspect ratios of the three orientations of a given grain best quantifies the degree of elongation of that grain. However, the average aspect ratio calculated for each grain provides a good representation of relative differences among grains. We also find that convexity provides the best representation of surface irregularity. For both shape parameters, natural ash grains display notably different shape parameter values than sphere analogs. Therefore, Mars ash dispersal modeling that incorporates shape parameters will provide more realistic predictions of deposit extents because volcanic ash-grain morphologies differ substantially from simplified geometric shapes.
The Practical Application of Uav-Based Photogrammetry Under Economic Aspects
NASA Astrophysics Data System (ADS)
Sauerbier, M.; Siegrist, E.; Eisenbeiss, H.; Demir, N.
2011-09-01
Nowadays, small size UAVs (Unmanned Aerial Vehicles) have reached a level of practical reliability and functionality that enables this technology to enter the geomatics market as an additional platform for spatial data acquisition. Though one could imagine a wide variety of interesting sensors to be mounted on such a device, here we will focus on photogrammetric applications using digital cameras. In praxis, UAV-based photogrammetry will only be accepted if it a) provides the required accuracy and an additional value and b) if it is competitive in terms of economic application compared to other measurement technologies. While a) was already proven by the scientific community and results were published comprehensively during the last decade, b) still has to be verified under real conditions. For this purpose, a test data set representing a realistic scenario provided by ETH Zurich was used to investigate cost effectiveness and to identify weak points in the processing chain that require further development. Our investigations are limited to UAVs carrying digital consumer cameras, for larger UAVs equipped with medium format cameras the situation has to be considered as significantly different. Image data was acquired during flights using a microdrones MD4-1000 quadrocopter equipped with an Olympus PE-1 digital compact camera. From these images, a subset of 5 images was selected for processing in order to register the effort of time required for the whole production chain of photogrammetric products. We see the potential of mini UAV-based photogrammetry mainly in smaller areas, up to a size of ca. 100 hectares. Larger areas can be efficiently covered by small airplanes with few images, reducing processing effort drastically. In case of smaller areas of a few hectares only, it depends more on the products required. UAVs can be an enhancement or alternative to GNSS measurements, terrestrial laser scanning and ground based photogrammetry. We selected the above mentioned test data from a project featuring an area of interest within the practical range for mini UAVs. While flight planning and flight operation are already quite efficient processes, the bottlenecks identified are mainly related to image processing. Although we used specific software for image processing, the identified gaps in the processing chain today are valid for most commercial photogrammetric software systems on the market. An outlook proposing improvements for a practicable workflow applicable in projects in private economy will be given.
The association between sexual satisfaction and body image in women.
Pujols, Yasisca; Seal, Brooke N; Meston, Cindy M
2010-02-01
Although sexual functioning has been linked to sexual satisfaction, it only partially explains the degree to which women report being sexually satisfied. Other factors include quality of life, relational variables, and individual factors such as body image. Of the few studies that have investigated the link between body image and sexual satisfaction, most have considered body image to be a single construct and have shown mixed results. The present study assessed multiple body image variables in order to better understand which aspects of body image influence multiple domains of sexual satisfaction, including sexual communication, compatibility, contentment, personal concern, and relational concern in a community sample of women. Women between the ages of 18 and 49 years in sexual relationships (N = 154) participated in an Internet survey that assessed sexual functioning, five domains of sexual satisfaction, and several body image variables. Body image variables included the sexual attractiveness, weight concern, and physical condition subscales of the Body Esteem Scale, the appearance-based subscale of the Cognitive Distractions During Sexual Activity Scale, and body mass index. Total score of the Sexual Satisfaction Scale for Women was the main outcome measure. Sexual functioning was measured by a modified Female Sexual Function Index. Consistent with expectations, correlations indicated significant positive relationships between sexual functioning, sexual satisfaction, and all body image variables. A multiple regression analysis revealed that sexual satisfaction was predicted by high body esteem and low frequency of appearance-based distracting thoughts during sexual activity, even after controlling for sexual functioning status. Several aspects of body image, including weight concern, physical condition, sexual attractiveness, and thoughts about the body during sexual activity predict sexual satisfaction in women. The findings suggest that women who experience low sexual satisfaction may benefit from treatments that target these specific aspects of body image.
The extensor digitorum brevis: histological and histochemical aspects
Jennekens, F. G. I.; Tomlinson, B. E.; Walton, J. N.
1972-01-01
Samples of the extensor digitorum brevis muscle (EDB) obtained at necropsy from 26 subjects without known neuromuscular disease were examined histologically and histochemically. In the two youngest subjects, aged 2 months and 8 years, a mosaic distribution of type I and type II fibres was present. From the second decade onwards, increasing with age, the mosaic pattern was gradually replaced by groups of type I and type II fibres and areas of grouped fibre atrophy appeared. It is suggested that these findings may be explained by a slow process of denervation and reinnervation. This process does not seem to occur to the same extent in three other distal limb muscles from which specimens were also examined. Images PMID:4260286
NASA Astrophysics Data System (ADS)
Paar, G.
2009-04-01
At present, mainly the US have realized planetary space missions with essential robotics background. Joining institutions, companies and universities from different established groups in Europe and two relevant players from the US, the EC FP7 Project PRoVisG started in autumn 2008 to demonstrate the European ability of realizing high-level processing of robotic vision image products from the surface of planetary bodies. PRoVisG will build a unified European framework for Robotic Vision Ground Processing. State-of-art computer vision technology will be collected inside and outside Europe to better exploit the image data gathered during past, present and future robotic space missions to the Moon and the Planets. This will lead to a significant enhancement of the scientific, technologic and educational outcome of such missions. We report on the main PRoVisG objectives and the development status: - Past, present and future planetary robotic mission profiles are analysed in terms of existing solutions and requirements for vision processing - The generic processing chain is based on unified vision sensor descriptions and processing interfaces. Processing components available at the PRoVisG Consortium Partners will be completed by and combined with modules collected within the international computer vision community in the form of Announcements of Opportunity (AOs). - A Web GIS is developed to integrate the processing results obtained with data from planetary surfaces into the global planetary context. - Towards the end of the 39 month project period, PRoVisG will address the public by means of a final robotic field test in representative terrain. The European tax payers will be able to monitor the imaging and vision processing in a Mars - similar environment, thus getting an insight into the complexity and methods of processing, the potential and decision making of scientific exploitation of such data and not least the elegancy and beauty of the resulting image products and their visualization. - The educational aspect is addressed by two summer schools towards the end of the project, presenting robotic vision to the students who are future providers of European science and technology, inside and outside the space domain.
Van Neste, Dominique
2014-01-01
The words "hair growth" frequently encompass many aspects other than just growth. Report on a validation method for precise non-invasive measurement of thickness together with linear hair growth rates of individual hair fibres. To verify the possible correlation between thickness and linear growth rate of scalp hair in male pattern hair loss as compared with healthy male controls. To document the process of validation of hair growth measurement from in vivo image capturing and manual processing, followed by computer assisted image analysis. We analysed 179 paired images obtained with the contrast-enhanced-phototrichogram method with exogen collection (CE-PTG-EC) in 13 healthy male controls and in 87 men with male pattern hair loss (MPHL). There was a global positive correlation between thickness and growth rate (ANOVA; p<0.0001) and a statistically significantly (ANOVA; p<0.0005) slower growth rate in MPHL as compared with equally thick hairs from controls. Finally, the growth rate recorded in the more severe patterns was significantly (ANOVA; P ≤ 0.001) reduced compared with equally thick hair from less severely affected MPHL or controls subjects. Reduced growth rate, together with thinning and shortening of the anagen phase duration in MPHL might contribute together to the global impression of decreased hair volume on the top of the head. Amongst other structural and functional parameters characterizing hair follicle regression, linear hair growth rate warrants further investigation, as it may be relevant in terms of self-perception of hair coverage, quantitative diagnosis and prognostic factor of the therapeutic response.
A neuromorphic approach to satellite image understanding
NASA Astrophysics Data System (ADS)
Partsinevelos, Panagiotis; Perakakis, Manolis
2014-05-01
Remote sensing satellite imagery provides high altitude, top viewing aspects of large geographic regions and as such the depicted features are not always easily recognizable. Nevertheless, geoscientists familiar to remote sensing data, gradually gain experience and enhance their satellite image interpretation skills. The aim of this study is to devise a novel computational neuro-centered classification approach for feature extraction and image understanding. Object recognition through image processing practices is related to a series of known image/feature based attributes including size, shape, association, texture, etc. The objective of the study is to weight these attribute values towards the enhancement of feature recognition. The key cognitive experimentation concern is to define the point when a user recognizes a feature as it varies in terms of the above mentioned attributes and relate it with their corresponding values. Towards this end, we have set up an experimentation methodology that utilizes cognitive data from brain signals (EEG) and eye gaze data (eye tracking) of subjects watching satellite images of varying attributes; this allows the collection of rich real-time data that will be used for designing the image classifier. Since the data are already labeled by users (using an input device) a first step is to compare the performance of various machine-learning algorithms on the collected data. On the long-run, the aim of this work would be to investigate the automatic classification of unlabeled images (unsupervised learning) based purely on image attributes. The outcome of this innovative process is twofold: First, in an abundance of remote sensing image datasets we may define the essential image specifications in order to collect the appropriate data for each application and improve processing and resource efficiency. E.g. for a fault extraction application in a given scale a medium resolution 4-band image, may be more effective than costly, multispectral, very high resolution imagery. Second, we attempt to relate the experienced against the non-experienced user understanding in order to indirectly assess the possible limits of purely computational systems. In other words, obtain the conceptual limits of computation vs human cognition concerning feature recognition from satellite imagery. Preliminary results of this pilot study show relations between collected data and differentiation of the image attributes which indicates that our methodology can lead to important results.
Basic Energy Sciences Program Update
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
2016-01-04
The U.S. Department of Energy’s (DOE) Office of Basic Energy Sciences (BES) supports fundamental research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels to provide the foundations for new energy technologies and to support DOE missions in energy, environment, and national security. The research disciplines covered by BES—condensed matter and materials physics, chemistry, geosciences, and aspects of physical biosciences— are those that discover new materials and design new chemical processes. These disciplines touch virtually every aspect of energy resources, production, conversion, transmission, storage, efficiency, and waste mitigation. BES also plans, constructs, andmore » operates world-class scientific user facilities that provide outstanding capabilities for imaging and spectroscopy, characterizing materials of all kinds ranging from hard metals to fragile biological samples, and studying the chemical transformation of matter. These facilities are used to correlate the microscopic structure of materials with their macroscopic properties and to study chemical processes. Such experiments provide critical insights to electronic, atomic, and molecular configurations, often at ultrasmall length and ultrafast time scales.« less
Threat perception in mild cognitive impairment and early dementia.
Henry, Julie D; Thompson, Claire; Ruffman, Ted; Leslie, Felicity; Withall, Adrienne; Sachdev, Perminder; Brodaty, Henry
2009-09-01
Mild cognitive impairment (MCI) and dementia affect many aspects of emotion processing. Even though the ability to detect threat is a particularly important aspect of emotion processing, no study to date has assessed threat perception in either of these groups. The purpose of the present study was to test whether individuals with MCI (n = 38) and mild dementia (n = 34) have difficulty differentiating between faces and situations normatively judged to be either high or low in threat relative to age-matched controls (n = 34). To achieve this aim, all participants completed 2 danger rating tasks that involved viewing and rating high- and low-danger images. It was also assessed whether threat perception was related to cognitive functioning and emotion recognition. The results indicated that all 3 groups were accurately, and comparably, able to differentiate high from low-danger faces. However, the dementia group had difficulties differentiating high from low-danger situations, which reflected a bias to overattribute the level of threat posed by normatively judged nonthreatening situations. This difficulty was related to more general cognitive decline.
Multislice CT perfusion imaging of the lung in detection of pulmonary embolism
NASA Astrophysics Data System (ADS)
Hong, Helen; Lee, Jeongjin
2006-03-01
We propose a new subtraction technique for accurately imaging lung perfusion and efficiently detecting pulmonary embolism in chest MDCT angiography. Our method is composed of five stages. First, optimal segmentation technique is performed for extracting same volume of the lungs, major airway and vascular structures from pre- and post-contrast images with different lung density. Second, initial registration based on apex, hilar point and center of inertia (COI) of each unilateral lung is proposed to correct the gross translational mismatch. Third, initial alignment is refined by iterative surface registration. For fast and robust convergence of the distance measure to the optimal value, a 3D distance map is generated by the narrow-band distance propagation. Fourth, 3D nonlinear filter is applied to the lung parenchyma to compensate for residual spiral artifacts and artifacts caused by heart motion. Fifth, enhanced vessels are visualized by subtracting registered pre-contrast images from post-contrast images. To facilitate visualization of parenchyma enhancement, color-coded mapping and image fusion is used. Our method has been successfully applied to ten patients of pre- and post-contrast images in chest MDCT angiography. Experimental results show that the performance of our method is very promising compared with conventional methods with the aspects of its visual inspection, accuracy and processing time.
NASA Astrophysics Data System (ADS)
Zeilhofer, Hans-Florian U.; Krol, Zdzislaw; Sader, Robert; Hoffmann, Karl-Heinz; Gerhardt, Paul; Schweiger, Markus; Horch, Hans-Henning
1997-05-01
For several diseases in the head and neck area different imaging modalities are applied to the same patient.Each of these image data sets has its specific advantages and disadvantages. The combination of different methods allows to make the best use of the advantageous properties of each method while minimizing the impact of its negative aspects. Soft tissue alterations can be judged better in an MRI image while it may be unrecognizable in the relating CT. Bone tissue, on the other hand, is optimally imaged in CT. Inflammatory nuclei of the bone can be detected best by their increased signal in SPECT. Only the combination of all modalities let the physical come to an exact statement on pathological processes that involve multiple tissue structures. Several surfaces and voxel based matching functions we have tested allowed a precise merging by means of numerical optimization methods like e.g. simulated annealing without the complicated assertion of fiducial markers or the localization landmarks in 2D cross sectional slice images. The quality of the registration depends on the choice of the optimization procedure according to the complexity of the matching function landscape. Precise correlation of the multimodal head and neck area images together with its 2D and 3D presentation techniques provides a valuable tool for physicians.
Kawooya, Michael G.; Pariyo, George; Malwadde, Elsie Kiguli; Byanyima, Rosemary; Kisembo, Harrient
2012-01-01
Objectives: Uganda, has limited health resources and improving performance of personnel involved in imaging is necessary for efficiency. The objectives of the study were to develop and pilot imaging user performance indices, document non-tangible aspects of performance, and propose ways of improving performance. Materials and Methods: This was a cross-sectional survey employing triangulation methodology, conducted in Mulago National Referral Hospital over a period of 3 years from 2005 to 2008. The qualitative study used in-depth interviews, focus group discussions, and self-administered questionnaires, to explore clinicians’ and radiologists’ performancerelated views. Results: The study came up with following indices: appropriate service utilization (ASU), appropriateness of clinician's nonimaging decisions (ANID), and clinical utilization of imaging results (CUI). The ASU, ANID, and CUI were: 94%, 80%, and 97%, respectively. The clinician's requisitioning validity was high (positive likelihood ratio of 10.6) contrasting with a poor validity for detecting those patients not needing imaging (negative likelihood ratio of 0.16). Some requisitions were inappropriate and some requisition and reports lacked detail, clarity, and precision. Conclusion: Clinicians perform well at imaging requisition-decisions but there are issues in imaging requisitioning and reporting that need to be addressed to improve performance. PMID:23230543
Autonomous caregiver following robotic wheelchair
NASA Astrophysics Data System (ADS)
Ratnam, E. Venkata; Sivaramalingam, Sethurajan; Vignesh, A. Sri; Vasanth, Elanthendral; Joans, S. Mary
2011-12-01
In the last decade, a variety of robotic/intelligent wheelchairs have been proposed to meet the need in aging society. Their main research topics are autonomous functions such as moving toward some goals while avoiding obstacles, or user-friendly interfaces. Although it is desirable for wheelchair users to go out alone, caregivers often accompany them. Therefore we have to consider not only autonomous functions and user interfaces but also how to reduce caregivers' load and support their activities in a communication aspect. From this point of view, we have proposed a robotic wheelchair moving with a caregiver side by side based on the MATLAB process. In this project we discussing about robotic wheel chair to follow a caregiver by using a microcontroller, Ultrasonic sensor, keypad, Motor drivers to operate robot. Using camera interfaced with the DM6437 (Davinci Code Processor) image is captured. The captured image are then processed by using image processing technique, the processed image are then converted into voltage levels through MAX 232 level converter and given it to the microcontroller unit serially and ultrasonic sensor to detect the obstacle in front of robot. In this robot we have mode selection switch Automatic and Manual control of robot, we use ultrasonic sensor in automatic mode to find obstacle, in Manual mode to use the keypad to operate wheel chair. In the microcontroller unit, c language coding is predefined, according to this coding the robot which connected to it was controlled. Robot which has several motors is activated by using the motor drivers. Motor drivers are nothing but a switch which ON/OFF the motor according to the control given by the microcontroller unit.
Current Controversies in Diagnosis and Management of Cleft Palate and Velopharyngeal Insufficiency
Ysunza, Pablo Antonio; Repetto, Gabriela M.; Pamplona, Maria Carmen; Calderon, Juan F.; Shaheen, Kenneth; Chaiyasate, Konkgrit; Rontal, Matthew
2015-01-01
Background. One of the most controversial topics concerning cleft palate is the diagnosis and treatment of velopharyngeal insufficiency (VPI). Objective. This paper reviews current genetic aspects of cleft palate, imaging diagnosis of VPI, the planning of operations for restoring velopharyngeal function during speech, and strategies for speech pathology treatment of articulation disorders in patients with cleft palate. Materials and Methods. An updated review of the scientific literature concerning genetic aspects of cleft palate was carried out. Current strategies for assessing and treating articulation disorders associated with cleft palate were analyzed. Imaging procedures for assessing velopharyngeal closure during speech were reviewed, including a recent method for performing intraoperative videonasopharyngoscopy. Results. Conclusions from the analysis of genetic aspects of syndromic and nonsyndromic cleft palate and their use in its diagnosis and management are presented. Strategies for classifying and treating articulation disorders in patients with cleft palate are presented. Preliminary results of the use of multiplanar videofluoroscopy as an outpatient procedure and intraoperative endoscopy for the planning of operations which aimed to correct VPI are presented. Conclusion. This paper presents current aspects of the diagnosis and management of patients with cleft palate and VPI including 3 main aspects: genetics and genomics, speech pathology and imaging diagnosis, and surgical management. PMID:26273595
Wagner, John H; Miskelly, Gordon M
2003-05-01
The combination of photographs taken at two or three wavelengths at and bracketing an absorbance peak indicative of a particular compound can lead to an image with enhanced visualization of the compound. This procedure works best for compounds with absorbance bands that are narrow compared with "average" chromophores. If necessary, the photographs can be taken with different exposure times to ensure that sufficient light from the substrate is detected at all three wavelengths. The combination of images is readily performed if the images are obtained with a digital camera and are then processed using an image processing program. Best results are obtained if linear images at the peak maximum, at a slightly shorter wavelength, and at a slightly longer wavelength are used. However, acceptable results can also be obtained under many conditions if non-linear photographs are used or if only two wavelengths (one of which is at the peak maximum) are combined. These latter conditions are more achievable by many "mid-range" digital cameras. Wavelength selection can either be by controlling the illumination (e.g., by using an alternate light source) or by use of narrow bandpass filters. The technique is illustrated using blood as the target analyte, using bands of light centered at 395, 415, and 435 nm. The extension of the method to detection of blood by fluorescence quenching is also described.
Studying cytokinesis in Drosophila epithelial tissues.
Pinheiro, D; Bellaïche, Y
2017-01-01
Epithelial tissue cohesiveness is ensured through cell-cell junctions that maintain both adhesion and mechanical coupling between neighboring cells. During development, epithelial tissues undergo intensive cell proliferation. Cell division, and particularly cytokinesis, is coupled to the formation of new adhesive contacts, thereby preserving tissue integrity and propagating cell polarity. Remarkably, the geometry of the new interfaces is determined by the combined action of the dividing cell and its neighbors. To further understand the interplay between the dividing cell and its neighbors, as well as the role of cell division for tissue morphogenesis, it is important to analyze cytokinesis in vivo. Here we present methods to perform live imaging of cell division in Drosophila epithelial tissues and discuss some aspects of image processing and analysis. Copyright © 2017 Elsevier Inc. All rights reserved.
New developments in electron microscopy for serial image acquisition of neuronal profiles.
Kubota, Yoshiyuki
2015-02-01
Recent developments in electron microscopy largely automate the continuous acquisition of serial electron micrographs (EMGs), previously achieved by laborious manual serial ultrathin sectioning using an ultramicrotome and ultrastructural image capture process with transmission electron microscopy. The new systems cut thin sections and capture serial EMGs automatically, allowing for acquisition of large data sets in a reasonably short time. The new methods are focused ion beam/scanning electron microscopy, ultramicrotome/serial block-face scanning electron microscopy, automated tape-collection ultramicrotome/scanning electron microscopy and transmission electron microscope camera array. In this review, their positive and negative aspects are discussed. © The Author 2015. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Sandoval, Guillermo A; Brown, Adalsteinn D; Wodchis, Walter P; Anderson, Geoffrey M
2018-05-17
Measuring the value of medical imaging is challenging, in part, due to the lack of conceptual frameworks underlying potential mechanisms where value may be assessed. To address this gap, this article proposes a framework that builds on the large body of literature on quality of hospital care and the classic structure-process-outcome paradigm. The framework was also informed by the literature on adoption of technological innovations and introduces 2 distinct though related aspects of imaging technology not previously addressed specifically in the literature on quality of hospital care: adoption (a structural hospital characteristic) and use (an attribute of the process of care). The framework hypothesizes a 2-part causality where adoption is proposed to be a central, linking factor between hospital structural characteristics, market factors, and hospital outcomes (ie, quality and efficiency). The first part indicates that hospital structural characteristics and market factors influence or facilitate the adoption of high technology medical imaging within an institution. The presence of this technology, in turn, is hypothesized to improve the ability of the hospital to deliver high quality and efficient care. The second part describes this ability throughout 3 main mechanisms pointing to the importance of imaging use on patients, to the presence of staff and qualified care providers, and to some elements of organizational capacity capturing an enhanced clinical environment. The framework has the potential to assist empirical investigations of the value of adoption and use of medical imaging, and to advance understanding of the mechanisms that produce quality and efficiency in hospitals. Copyright © 2018 John Wiley & Sons, Ltd.
Proton magnetic resonance spectroscopy imaging in the study of human brain cancer.
Martínez-Bisbal, M C; Celda, B
2009-12-01
Magnetic resonance spectroscopic imaging (MRSI) is a non-invasive imaging technique that provides metabolic information on brain tumor. This biochemical information can be processed and presented as density maps of several metabolites, among them N-acetylaspartate (marker of neuronal viability), choline (marker of membrane turnover), creatine (related to the energy state of the cells), myo-Inositol (exclusively found in astrocytes), lipids and lactate (observed in necrosis and other pathological processes) which mean relevant information in the context of brain tumors. Thus, this technique is a multiparametrical molecular imaging method that can complete the magnetic resonance imaging (MRI) study enabling the detection of biochemical patterns of different features and aspects of brain tumors. In this article, the role of MRSI as a molecular imaging technique to provide biochemical information on human brain tumors is reviewed. The most frequent questions and situations in the study of human brain tumors in clinical settings will be considered, as well as the distinction of neoplastic lesions from non neoplastic, the tumor type identification, the study of heterogeneity and infiltration of normal appearing white matter and the therapy following with detection of side effects. The great amount of data in MRSI acquisition compared to the single voxel techniques requires the use of automated methods of quantification, but the possibility to obtain self-reference in the non-affected areas allows different strategies for data handling and interpretation, as presented in the literature. The combination of MRSI with other physiological MRI techniques and positron emission tomography is also included in this review.
Kessel, Ellen M; Kujawa, Autumn; Goldstein, Brandon; Hajcak, Greg; Bufferd, Sara J; Dyson, Margaret; Klein, Daniel N
2017-07-01
The Research Domain Criteria (RDoC) constructs of Positive Valence Systems (PVS) and Negative Valence Systems (NVS) are presumed to manifest behaviorally through early-emerging temperamental negative affectivity (NA) and positive affectivity (PA). The late positive potential (LPP) is a physiological measure of attention towards both negative and positive emotional stimuli; however, its associations with behavioral aspects of PVS and NVS have yet to be examined. In a community sample of children (N = 340), we examined longitudinal relationships between observational measures of temperamental PA and NA assessed at age 6, and the LPP to both pleasant and unpleasant images assessed at age 9. Lower PA at age 6 predicted reduced LPP amplitudes to pleasant, but not unpleasant, images. NA as a composite measure was not related to the LPP, but specific associations were observed with facets of NA: greater fear predicted an enhanced LPP to unpleasant images, whereas greater sadness predicted a reduced LPP to unpleasant images. We were unable to evaluate concurrent associations between behavioral observations of temperament and the LPP, and effect sizes were modest. Results support correspondence between behavioral and physiological measures of emotional processing across development, and provide evidence of discriminant validity in that PA was specifically related to the LPP to pleasant images, while facets of NA were specifically linked to the LPP to unpleasant images. Distinct associations of temperamental sadness and fear with the LPP highlight the importance of further evaluating subconstructs of NVS. Copyright © 2016 Elsevier B.V. All rights reserved.
Pobric, Gorana; Lambon Ralph, Matthew A.; Jefferies, Elizabeth
2009-01-01
Conceptual knowledge allows us to bring meaning to our world. Studies of semantic dementia (SD) patients and some functional neuroimaging studies indicate that the anterior temporal lobes, bilaterally, are a core neural substrate for the formation of conceptual representations. The majority of SD patients (who have circumscribed atrophy of the anterior temporal lobes) have better comprehension of concrete than abstract words. However, this finding remains controversial, as some individual SD patients have exhibited reverse imageability effects, i.e., relative preservation of abstract knowledge. This would imply that the anterior temporal lobes are particularly crucial for processing sensory aspects of semantic knowledge, which are an important part of concrete but not abstract concepts. To adjudicate on this debate, we used offline, low-frequency, repetitive transcranial magnetic stimulation to disrupt neural processing temporarily in the left or right temporal poles (TPs). We examined this effect using a synonym judgement task, comprising high, medium and low imageability items, which we have previously employed with a case-series of SD patients. The time required to make semantic decisions was slowed considerably, particularly for low imageability items, consistent with the pattern we observed in SD. These results confirm that both TPs make a critical contribution to semantic processing, even for abstract concepts that do not have strong sensory representations. PMID:19303592
Farrar, Stephanie; Stopa, Lusia; Turner, Hannah
2015-03-01
Cognitive behavioural models of eating disorders highlight low self-esteem as a maintaining factor. This study explored the impact of positive and negative self-imagery on aspects of the working self (implicit and explicit self-esteem and self-concept clarity) in individuals with high body dissatisfaction (an important aspect of eating disorders). The impact of these images on state body satisfaction and affect was also explored. A group of participants with high body dissatisfaction completed measures of explicit self-esteem, self-concept clarity, state body satisfaction and affect prior to completing a negative (n = 33) or positive (n = 33) self-imagery retrieval task. Following this they completed the baseline measures and a measure of implicit self-esteem. Holding a negative self-image in mind had a negative effect on explicit self-esteem, whilst holding a positive self-image had a beneficial effect. There were no effects of imagery on implicit self-esteem. Holding a negative image in mind led to a significant reduction in self-concept clarity; however, positive self-imagery did not affect self-concept clarity. Holding a negative self-image in mind led to a decrease in body satisfaction and state affect. The opposite was found for the positive self-imagery group. Implicit self-esteem was not measured at baseline. Imagery techniques which promote positive self-images may help improve aspects of the working self, body satisfaction and affect in individuals with high levels of body dissatisfaction. As such, these imagery techniques warrant further investigation in a clinical population. Copyright © 2014 Elsevier Ltd. All rights reserved.
Electronic document management systems: an overview.
Kohn, Deborah
2002-08-01
For over a decade, most health care information technology (IT) professionals erroneously learned that document imaging, which is one of the many component technologies of an electronic document management system (EDMS), is the only technology of an EDMS. In addition, many health care IT professionals erroneously believed that EDMSs have either a limited role or no place in IT environments. As a result, most health care IT professionals do not understand documents and unstructured data and their value as structured data partners in most aspects of transaction and information processing systems.
Monolithically Integrated, Mechanically Resilient Carbon-Based Probes for Scanning Probe Microscopy
NASA Technical Reports Server (NTRS)
Kaul, Anupama B.; Megerian, Krikor G.; Jennings, Andrew T.; Greer, Julia R.
2010-01-01
Scanning probe microscopy (SPM) is an important tool for performing measurements at the nanoscale in imaging bacteria or proteins in biology, as well as in the electronics industry. An essential element of SPM is a sharp, stable tip that possesses a small radius of curvature to enhance spatial resolution. Existing techniques for forming such tips are not ideal. High-aspect-ratio, monolithically integrated, as-grown carbon nanofibers (CNFs) have been formed that show promise for SPM applications by overcoming the limitations present in wet chemical and separate substrate etching processes.
It takes two-coincidence coding within the dual olfactory pathway of the honeybee.
Brill, Martin F; Meyer, Anneke; Rössler, Wolfgang
2015-01-01
To rapidly process biologically relevant stimuli, sensory systems have developed a broad variety of coding mechanisms like parallel processing and coincidence detection. Parallel processing (e.g., in the visual system), increases both computational capacity and processing speed by simultaneously coding different aspects of the same stimulus. Coincidence detection is an efficient way to integrate information from different sources. Coincidence has been shown to promote associative learning and memory or stimulus feature detection (e.g., in auditory delay lines). Within the dual olfactory pathway of the honeybee both of these mechanisms might be implemented by uniglomerular projection neurons (PNs) that transfer information from the primary olfactory centers, the antennal lobe (AL), to a multimodal integration center, the mushroom body (MB). PNs from anatomically distinct tracts respond to the same stimulus space, but have different physiological properties, characteristics that are prerequisites for parallel processing of different stimulus aspects. However, the PN pathways also display mirror-imaged like anatomical trajectories that resemble neuronal coincidence detectors as known from auditory delay lines. To investigate temporal processing of olfactory information, we recorded PN odor responses simultaneously from both tracts and measured coincident activity of PNs within and between tracts. Our results show that coincidence levels are different within each of the two tracts. Coincidence also occurs between tracts, but to a minor extent compared to coincidence within tracts. Taken together our findings support the relevance of spike timing in coding of olfactory information (temporal code).
Telling true from false: cannabis users show increased susceptibility to false memories.
Riba, J; Valle, M; Sampedro, F; Rodríguez-Pujadas, A; Martínez-Horta, S; Kulisevsky, J; Rodríguez-Fornells, A
2015-06-01
Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring.
NASA Astrophysics Data System (ADS)
Denker, Carsten; Kuckein, Christoph; Verma, Meetu; González Manrique, Sergio J.; Diercke, Andrea; Enke, Harry; Klar, Jochen; Balthasar, Horst; Louis, Rohan E.; Dineva, Ekaterina
2018-05-01
In high-resolution solar physics, the volume and complexity of photometric, spectroscopic, and polarimetric ground-based data significantly increased in the last decade, reaching data acquisition rates of terabytes per hour. This is driven by the desire to capture fast processes on the Sun and the necessity for short exposure times “freezing” the atmospheric seeing, thus enabling ex post facto image restoration. Consequently, large-format and high-cadence detectors are nowadays used in solar observations to facilitate image restoration. Based on our experience during the “early science” phase with the 1.5 m GREGOR solar telescope (2014–2015) and the subsequent transition to routine observations in 2016, we describe data collection and data management tailored toward image restoration and imaging spectroscopy. We outline our approaches regarding data processing, analysis, and archiving for two of GREGOR’s post-focus instruments (see http://gregor.aip.de), i.e., the GREGOR Fabry–Pérot Interferometer (GFPI) and the newly installed High-Resolution Fast Imager (HiFI). The heterogeneous and complex nature of multidimensional data arising from high-resolution solar observations provides an intriguing but also a challenging example for “big data” in astronomy. The big data challenge has two aspects: (1) establishing a workflow for publishing the data for the whole community and beyond and (2) creating a collaborative research environment (CRE), where computationally intense data and postprocessing tools are colocated and collaborative work is enabled for scientists of multiple institutes. This requires either collaboration with a data center or frameworks and databases capable of dealing with huge data sets based on virtual observatory (VO) and other community standards and procedures.
Uav Photogrammetry with Oblique Images: First Analysis on Data Acquisition and Processing
NASA Astrophysics Data System (ADS)
Aicardi, I.; Chiabrando, F.; Grasso, N.; Lingua, A. M.; Noardo, F.; Spanò, A.
2016-06-01
In recent years, many studies revealed the advantages of using airborne oblique images for obtaining improved 3D city models (e.g. including façades and building footprints). Expensive airborne cameras, installed on traditional aerial platforms, usually acquired the data. The purpose of this paper is to evaluate the possibility of acquire and use oblique images for the 3D reconstruction of a historical building, obtained by UAV (Unmanned Aerial Vehicle) and traditional COTS (Commercial Off-the-Shelf) digital cameras (more compact and lighter than generally used devices), for the realization of high-level-of-detail architectural survey. The critical issues of the acquisitions from a common UAV (flight planning strategies, ground control points, check points distribution and measurement, etc.) are described. Another important considered aspect was the evaluation of the possibility to use such systems as low cost methods for obtaining complete information from an aerial point of view in case of emergency problems or, as in the present paper, in the cultural heritage application field. The data processing was realized using SfM-based approach for point cloud generation: different dense image-matching algorithms implemented in some commercial and open source software were tested. The achieved results are analysed and the discrepancies from some reference LiDAR data are computed for a final evaluation. The system was tested on the S. Maria Chapel, a part of the Novalesa Abbey (Italy).
Unconventional methods of imaging: computational microscopy and compact implementations
NASA Astrophysics Data System (ADS)
McLeod, Euan; Ozcan, Aydogan
2016-07-01
In the past two decades or so, there has been a renaissance of optical microscopy research and development. Much work has been done in an effort to improve the resolution and sensitivity of microscopes, while at the same time to introduce new imaging modalities, and make existing imaging systems more efficient and more accessible. In this review, we look at two particular aspects of this renaissance: computational imaging techniques and compact imaging platforms. In many cases, these aspects go hand-in-hand because the use of computational techniques can simplify the demands placed on optical hardware in obtaining a desired imaging performance. In the first main section, we cover lens-based computational imaging, in particular, light-field microscopy, structured illumination, synthetic aperture, Fourier ptychography, and compressive imaging. In the second main section, we review lensfree holographic on-chip imaging, including how images are reconstructed, phase recovery techniques, and integration with smart substrates for more advanced imaging tasks. In the third main section we describe how these and other microscopy modalities have been implemented in compact and field-portable devices, often based around smartphones. Finally, we conclude with some comments about opportunities and demand for better results, and where we believe the field is heading.
Final Report 2007: DOE-FG02-87ER60561
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kilbourn, Michael R
2007-04-26
This project involved a multi-faceted approach to the improvement of techniques used in Positron Emission Tomography (PET), from radiochemistry to image processing and data analysis. New methods for radiochemical syntheses were examined, new radiochemicals prepared for evaluation and eventual use in human PET studies, and new pre-clinical methods examined for validation of biochemical parameters in animal studies. The value of small animal PET imaging in measuring small changes of in vivo biochemistry was examined and directly compared to traditional tissue sampling techniques. In human imaging studies, the ability to perform single experimental sessions utilizing two overlapping injections of radiopharmaceuticals wasmore » tested, and it was shown that valid biochemical measures for both radiotracers can be obtained through careful pharmacokinetic modeling of the PET emission data. Finally, improvements in reconstruction algorithms for PET data from small animal PET scanners was realized and these have been implemented in commercial releases. Together, the project represented an integrated effort to improve and extend all basic science aspects of PET imaging at both the animal and human level.« less
NASA Technical Reports Server (NTRS)
Partridge, James D.
2002-01-01
'NASA is preparing to launch the Next Generation Space Telescope (NGST). This telescope will be larger than the Hubble Space Telescope, be launched on an Atlas missile rather than the Space Shuttle, have a segmented primary mirror, and be placed in a higher orbit. All these differences pose significant challenges.' This effort addresses the challenge of implementing an algorithm for aligning the segments of the primary mirror during the initial deployment that was designed by Philip Olivier and members of SOMTC (Space Optics Manufacturing Technology Center). The implementation was to be performed on the SIBOA (Systematic Image Based Optical Alignment) test bed. Unfortunately, hardware/software aspect concerning SIBOA and an extended time period for algorithm development prevented testing before the end of the study period. Properties of the digital camera were studied and understood, resulting in the current ability of selecting optimal settings regarding saturation. The study was successful in manually capturing several images of two stacked segments with various relative phases. These images can be used to calibrate the algorithm for future implementation. Currently the system is ready for testing.
Multiple Representations-Based Face Sketch-Photo Synthesis.
Peng, Chunlei; Gao, Xinbo; Wang, Nannan; Tao, Dacheng; Li, Xuelong; Li, Jie
2016-11-01
Face sketch-photo synthesis plays an important role in law enforcement and digital entertainment. Most of the existing methods only use pixel intensities as the feature. Since face images can be described using features from multiple aspects, this paper presents a novel multiple representations-based face sketch-photo-synthesis method that adaptively combines multiple representations to represent an image patch. In particular, it combines multiple features from face images processed using multiple filters and deploys Markov networks to exploit the interacting relationships between the neighboring image patches. The proposed framework could be solved using an alternating optimization strategy and it normally converges in only five outer iterations in the experiments. Our experimental results on the Chinese University of Hong Kong (CUHK) face sketch database, celebrity photos, CUHK Face Sketch FERET Database, IIIT-D Viewed Sketch Database, and forensic sketches demonstrate the effectiveness of our method for face sketch-photo synthesis. In addition, cross-database and database-dependent style-synthesis evaluations demonstrate the generalizability of this novel method and suggest promising solutions for face identification in forensic science.
Wide-field ultraviolet imager for astronomical transient studies
NASA Astrophysics Data System (ADS)
Mathew, Joice; Ambily, S.; Prakash, Ajin; Sarpotdar, Mayuresh; Nirmal, K.; G. Sreejith, A.; Safonova, Margarita; Murthy, Jayant; Brosch, Noah
2018-04-01
Though the ultraviolet (UV) domain plays a vital role in the studies of astronomical transient events, the UV time-domain sky remains largely unexplored. We have designed a wide-field UV imager that can be flown on a range of available platforms, such as high-altitude balloons, CubeSats, and larger space missions. The major scientific goals are the variability of astronomical sources, detection of transients such as supernovae, novae, tidal disruption events, and characterizing active galactic nuclei variability. The instrument has a 80 mm aperture with a circular field of view of 10.8 degrees, an angular resolution of ˜22 arcsec, and a 240 - 390 nm spectral observation window. The detector for the instrument is a Microchannel Plate (MCP)-based image intensifier with both photon counting and integration capabilities. An FPGA-based detector readout mechanism and real time data processing have been implemented. The imager is designed in such a way that its lightweight and compact nature are well fitted for the CubeSat dimensions. Here we present various design and developmental aspects of this UV wide-field transient explorer.
NASA Astrophysics Data System (ADS)
Elshahaby, Fatma E. A.; Ghaly, Michael; Jha, Abhinav K.; Frey, Eric C.
2015-03-01
Model Observers are widely used in medical imaging for the optimization and evaluation of instrumentation, acquisition parameters and image reconstruction and processing methods. The channelized Hotelling observer (CHO) is a commonly used model observer in nuclear medicine and has seen increasing use in other modalities. An anthropmorphic CHO consists of a set of channels that model some aspects of the human visual system and the Hotelling Observer, which is the optimal linear discriminant. The optimality of the CHO is based on the assumption that the channel outputs for data with and without the signal present have a multivariate normal distribution with equal class covariance matrices. The channel outputs result from the dot product of channel templates with input images and are thus the sum of a large number of random variables. The central limit theorem is thus often used to justify the assumption that the channel outputs are normally distributed. In this work, we aim to examine this assumption for realistically simulated nuclear medicine images when various types of signal variability are present.
Vu, Cung; Nihei, Kurt T; Schmitt, Denis P; Skelt, Christopher; Johnson, Paul A; Guyer, Robert; TenCate, James A; Le Bas, Pierre-Yves
2012-10-16
In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region remote from a borehole using a conveyed logging tool is disclosed. In some aspects, the method includes arranging a first source in the borehole and generating a steered beam of elastic energy at a first frequency; arranging a second source in the borehole and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location away from the borehole; receiving at the borehole by a sensor a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole; determining a location of a three wave mixing region based on the arrangement of the first and second sources and on properties of the third wave signal; and creating three-dimensional images of the non-linear properties using data recorded by repeating the generating, receiving and determining at a plurality of azimuths, inclinations and longitudinal locations within the borehole. The method is additionally used to generate three dimensional images of the ratio of compressional to shear acoustic velocity of the same volume surrounding the borehole.
Flexible real-time magnetic resonance imaging framework.
Santos, Juan M; Wright, Graham A; Pauly, John M
2004-01-01
The extension of MR imaging to new applications has demonstrated the limitations of the architecture of current real-time systems. Traditional real-time implementations provide continuous acquisition of data and modification of basic sequence parameters on the fly. We have extended the concept of real-time MRI by designing a system that drives the examinations from a real-time localizer and then gets reconfigured for different imaging modes. Upon operator request or automatic feedback the system can immediately generate a new pulse sequence or change fundamental aspects of the acquisition such as gradient waveforms excitation pulses and scan planes. This framework has been implemented by connecting a data processing and control workstation to a conventional clinical scanner. Key components on the design of this framework are the data communication and control mechanisms, reconstruction algorithms optimized for real-time and adaptability, flexible user interface and extensible user interaction. In this paper we describe the various components that comprise this system. Some of the applications implemented in this framework include real-time catheter tracking embedded in high frame rate real-time imaging and immediate switching between real-time localizer and high-resolution volume imaging for coronary angiography applications.
Multimodal 3D cancer-mimicking optical phantom
Smith, Gennifer T.; Lurie, Kristen L.; Zlatev, Dimitar V.; Liao, Joseph C.; Ellerbee Bowden, Audrey K.
2016-01-01
Three-dimensional (3D) organ-mimicking phantoms provide realistic imaging environments for testing various aspects of optical systems, including for evaluating new probe designs, characterizing the diagnostic potential of new technologies, and assessing novel image processing algorithms prior to validation in real tissue. We introduce and characterize the use of a new material, Dragon Skin (Smooth-On Inc.), and fabrication technique, air-brushing, for fabrication of a 3D phantom that mimics the appearance of a real organ under multiple imaging modalities. We demonstrate the utility of the material and technique by fabricating the first 3D, hollow bladder phantom with realistic normal and multi-stage pathology features suitable for endoscopic detection using the gold standard imaging technique, white light cystoscopy (WLC), as well as the complementary imaging modalities of optical coherence tomography and blue light cystoscopy, which are aimed at improving the sensitivity and specificity of WLC to bladder cancer detection. The flexibility of the material and technique used for phantom construction allowed for the representation of a wide range of diseased tissue states, ranging from inflammation (benign) to high-grade cancerous lesions. Such phantoms can serve as important tools for trainee education and evaluation of new endoscopic instrumentation. PMID:26977369
NASA Astrophysics Data System (ADS)
Zhang, Guozhi; Petrov, Dimitar; Marshall, Nicholas; Bosmans, Hilde
2017-03-01
Digital breast tomosynthesis (DBT) is a relatively new diagnostic imaging modality for women. Currently, various models of DBT systems are available on the market and the number of installations is rapidly increasing. EUREF, the European Reference Organization for Quality Assured Breast Screening and Diagnostic Services, has proposed a preliminary Guideline - protocol for the quality control of the physical and technical aspects of digital breast tomosynthesis systems, with an ultimate aim of providing limiting values guaranteeing proper performance for different applications of DBT. In this work, we introduce an adaptive toolkit developed in accordance with this guideline to facilitate the process of image quality evaluation in DBT performance test. This toolkit implements robust algorithms to quantify various technical parameters of DBT images and provides a convenient user interface in practice. Each test is built into a separate module with configurations set corresponding to the European guideline, which can be easily adapted to different settings and extended with additional tests. This toolkit largely improves the efficiency for image quality evaluation of DBT. It is also going to evolve with the development of protocols in quality control of DBT systems.
NASA Astrophysics Data System (ADS)
Han, Jun Sae; Gal, Chang Woo; Park, Jae Man; Kim, Jong Hyun; Park, Seong Jin
2018-04-01
Aspect ratio effects in the micro-powder injection molding process were experimentally analyzed for fabrication of high-aspect-ratio piezoelectric ceramic structure. The mechanisms of critical defects have been studied according to individual manufacturing steps. In the molding process, incomplete filling phenomenon determines the critical aspect ratios of a micro pattern. According to mold temperature, an incomplete filling phenomenon has been analyzed with respect to different pattern sizes and aspect ratio. In demolding and drying process, the capillary behavior of sacrificial polymeric mold insert determines the critical aspect ratio of a micro pattern. With respect to pattern dimensions, slumping behavior has been analyzed. Based on our current systems, micro PZT feature has stability when it has lower aspect ratio than 5. Under optimized processing conditions, 20 μm and 40 μm ceramic rod array feature which has 5 of aspect ratio were successfully fabricated by the developed process. Further modification points to fabricate the smaller and higher feature were specifically addressed.
Einstein, Andrew J.; Blankstein, Ron; Andrews, Howard; Fish, Mathews; Padgett, Richard; Hayes, Sean W.; Friedman, John D.; Qureshi, Mehreen; Rakotoarivelo, Harivony; Slomka, Piotr; Nakazato, Ryo; Bokhari, Sabahat; Di Carli, Marcello; Berman, Daniel S.
2015-01-01
SPECT myocardial perfusion imaging (MPI) plays a central role in coronary artery disease diagnosis; but concerns exist regarding its radiation burden. Compared to standard Anger-SPECT (A-SPECT) cameras, new high-efficiency (HE) cameras with specialized collimators and solid-state cadmium-zinc-telluride detectors offer potential to maintain image quality (IQ), while reducing administered activity and thus radiation dose to patients. No previous study has compared IQ, interpretation, total perfusion deficit (TPD), or ejection fraction (EF) in patients receiving both ultra-low-dose (ULD) imaging on a HE-SPECT camera and standard low-dose (SLD) A-SPECT imaging. Methods We compared ULD-HE-SPECT to SLD-A-SPECT imaging by dividing the rest dose in 101 patients at 3 sites scheduled to undergo clinical A-SPECT MPI using a same day rest/stress Tc-99m protocol. Patients received HE-SPECT imaging following an initial ~130 MBq (3.5mCi) dose, and SLD-A-SPECT imaging following the remainder of the planned dose. Images were scored visually by 2 blinded readers for IQ and summed rest score (SRS). TPD and EF were assessed quantitatively. Results Mean activity was 134 MBq (3.62 mCi) for ULD-HE-SPECT (effective dose 1.15 mSv) and 278 MBq (7.50 mCi, 2.39 mSv) for SLD-A-SPECT. Overall IQ was superior for ULD-HE-SPECT (p<0.0001), with twice as many studies graded excellent quality. Extracardiac activity and overall perfusion assessment were similar. Between-method correlations were high for SRS (r=0.87), TPD (r=0.91), and EF (r=0.88). Conclusion ULD-HE-SPECT rest imaging correlates highly with SLD-A-SPECT. It has improved image quality, comparable extracardiac activity, and achieves radiation dose reduction to 1 mSv for a single injection. PMID:24982439
Imaging of Myocardial Fatty Acid Oxidation
Mather, Kieren J; DeGrado, Tim
2016-01-01
Myocardial fuel selection is a key feature of the health and function of the heart, with clear links between myocardial function and fuel selection and important impacts of fuel selection on ischemia tolerance. Radiopharmaceuticals provide uniquely valuable tools for in vivo, non-invasive assessment of these aspects of cardiac function and metabolism. Here we review the landscape of imaging probes developed to provide noninvasive assessment of myocardial fatty acid oxidation (MFAO). Also, we review the state of current knowledge that myocardial fatty acid imaging has helped establish of static and dynamic fuel selection that characterizes cardiac and cardiometabolic disease and the interplay between fuel selection and various aspects of cardiac function. PMID:26923433
van Veggel, Frank C J M; Dong, Cunhai; Johnson, Noah J J; Pichaandi, Jothirmayanantham
2012-12-07
In this feature article we will critically discuss the synthesis and characterisation aspects of Ln(3+)-doped nanoparticles (NPs) that show upconversion, upon 980 nm excitation. Upconversion is a non-linear process that converts two or more low-energy photons, often near-infrared photons, into one of higher energy, e.g. blue and 800 nm from Tm(3+) and green and red from Er(3+) or Ho(3+). Nearly all researchers use the absorption of 980 nm light by Yb(3+) as the sensitiser for the co-doped emissive Ln(3+) ions. The focus will be on LnF(3) and MLnF(4) (M = alkali metal) as the host matrix, because most progress has been made with these. In particular we will argue that a detailed understanding of how the dopant ions and the host Ln(3+) ions are distributed (in the core) and how (doped) shell growth occurs is not well understood. Moreover, their use as optical and magnetic resonance imaging contrast agents will be discussed. We will argue that deep-tissue imaging beyond 600 μm with retention of optical resolution, i.e. to see fine structure such as blood capillaries in brain tissues, has not yet been achieved. Three key parameters have been identified as impediments: (i) the low absorption efficiency of the Yb(3+) sensitiser, (ii) the low quantum yield of upconversion, and (iii) the long-lived excited states. On the other hand, there are very encouraging results that suggest that these nanoparticles could be developed into very potent magnetic resonance imaging (MRI) contrast agents.
NASA Astrophysics Data System (ADS)
van Veggel, Frank C. J. M.; Dong, Cunhai; Johnson, Noah J. J.; Pichaandi, Jothirmayanantham
2012-11-01
In this feature article we will critically discuss the synthesis and characterisation aspects of Ln3+-doped nanoparticles (NPs) that show upconversion, upon 980 nm excitation. Upconversion is a non-linear process that converts two or more low-energy photons, often near-infrared photons, into one of higher energy, e.g. blue and 800 nm from Tm3+ and green and red from Er3+ or Ho3+. Nearly all researchers use the absorption of 980 nm light by Yb3+ as the sensitiser for the co-doped emissive Ln3+ ions. The focus will be on LnF3 and MLnF4 (M = alkali metal) as the host matrix, because most progress has been made with these. In particular we will argue that a detailed understanding of how the dopant ions and the host Ln3+ ions are distributed (in the core) and how (doped) shell growth occurs is not well understood. Moreover, their use as optical and magnetic resonance imaging contrast agents will be discussed. We will argue that deep-tissue imaging beyond 600 μm with retention of optical resolution, i.e. to see fine structure such as blood capillaries in brain tissues, has not yet been achieved. Three key parameters have been identified as impediments: (i) the low absorption efficiency of the Yb3+ sensitiser, (ii) the low quantum yield of upconversion, and (iii) the long-lived excited states. On the other hand, there are very encouraging results that suggest that these nanoparticles could be developed into very potent magnetic resonance imaging (MRI) contrast agents.
Biological imaging in radiation therapy: role of positron emission tomography.
Nestle, Ursula; Weber, Wolfgang; Hentschel, Michael; Grosu, Anca-Ligia
2009-01-07
In radiation therapy (RT), staging, treatment planning, monitoring and evaluation of response are traditionally based on computed tomography (CT) and magnetic resonance imaging (MRI). These radiological investigations have the significant advantage to show the anatomy with a high resolution, being also called anatomical imaging. In recent years, so called biological imaging methods which visualize metabolic pathways have been developed. These methods offer complementary imaging of various aspects of tumour biology. To date, the most prominent biological imaging system in use is positron emission tomography (PET), whose diagnostic properties have clinically been evaluated for years. The aim of this review is to discuss the valences and implications of PET in RT. We will focus our evaluation on the following topics: the role of biological imaging for tumour tissue detection/delineation of the gross tumour volume (GTV) and for the visualization of heterogeneous tumour biology. We will discuss the role of fluorodeoxyglucose-PET in lung and head and neck cancer and the impact of amino acids (AA)-PET in target volume delineation of brain gliomas. Furthermore, we summarize the data of the literature about tumour hypoxia and proliferation visualized by PET. We conclude that, regarding treatment planning in radiotherapy, PET offers advantages in terms of tumour delineation and the description of biological processes. However, to define the real impact of biological imaging on clinical outcome after radiotherapy, further experimental, clinical and cost/benefit analyses are required.
TOPICAL REVIEW: Biological imaging in radiation therapy: role of positron emission tomography
NASA Astrophysics Data System (ADS)
Nestle, Ursula; Weber, Wolfgang; Hentschel, Michael; Grosu, Anca-Ligia
2009-01-01
In radiation therapy (RT), staging, treatment planning, monitoring and evaluation of response are traditionally based on computed tomography (CT) and magnetic resonance imaging (MRI). These radiological investigations have the significant advantage to show the anatomy with a high resolution, being also called anatomical imaging. In recent years, so called biological imaging methods which visualize metabolic pathways have been developed. These methods offer complementary imaging of various aspects of tumour biology. To date, the most prominent biological imaging system in use is positron emission tomography (PET), whose diagnostic properties have clinically been evaluated for years. The aim of this review is to discuss the valences and implications of PET in RT. We will focus our evaluation on the following topics: the role of biological imaging for tumour tissue detection/delineation of the gross tumour volume (GTV) and for the visualization of heterogeneous tumour biology. We will discuss the role of fluorodeoxyglucose-PET in lung and head and neck cancer and the impact of amino acids (AA)-PET in target volume delineation of brain gliomas. Furthermore, we summarize the data of the literature about tumour hypoxia and proliferation visualized by PET. We conclude that, regarding treatment planning in radiotherapy, PET offers advantages in terms of tumour delineation and the description of biological processes. However, to define the real impact of biological imaging on clinical outcome after radiotherapy, further experimental, clinical and cost/benefit analyses are required.
Poelmans, Jennifer; Himmelreich, Uwe; Vanherp, Liesbeth; Zhai, Luca; Hillen, Amy; Holvoet, Bryan; Belderbos, Sarah; Brock, Matthias; Maertens, Johan; Velde, Greetje Vande; Lagrou, Katrien
2018-05-14
Aspergillus fumigatus causes life-threatening lung infections in immunocompromised patients. Mouse models are extensively used in research to assess the in vivo efficacy of antifungals. In recent years, there has been an increasing interest in the use of non-invasive imaging techniques to evaluate experimental infections. However, single imaging modalities have limitations concerning the type of information they can provide. In this study, magnetic resonance imaging and bioluminescence imaging were combined to obtain longitudinal information on the extent of developing lesions and fungal load in a leucopenic mouse model of IPA. This multimodal imaging approach was used to assess changes occurring within lungs of infected mice receiving voriconazole treatment starting at different time points after infection. Results showed that IPA development depends on the inoculum size used to infect animals and that disease can be successfully prevented or treated by initiating intervention during early stages of infection. Furthermore, we demonstrated that reduction of the fungal load is not necessarily associated with the disappearance of lesions on anatomical lung images, especially when antifungal treatment coincides with immune recovery. In conclusion, multimodal imaging allows to investigate different aspects of disease progression or recovery by providing complementary information on dynamic processes, which are highly useful for assessing the efficacy of (novel) therapeutic compounds in a time- and labor-efficient manner. Copyright © 2018 American Society for Microbiology.
Yi, Jizheng; Mao, Xia; Chen, Lijiang; Xue, Yuli; Rovetta, Alberto; Caleanu, Catalin-Daniel
2015-01-01
Illumination normalization of face image for face recognition and facial expression recognition is one of the most frequent and difficult problems in image processing. In order to obtain a face image with normal illumination, our method firstly divides the input face image into sixteen local regions and calculates the edge level percentage in each of them. Secondly, three local regions, which meet the requirements of lower complexity and larger average gray value, are selected to calculate the final illuminant direction according to the error function between the measured intensity and the calculated intensity, and the constraint function for an infinite light source model. After knowing the final illuminant direction of the input face image, the Retinex algorithm is improved from two aspects: (1) we optimize the surround function; (2) we intercept the values in both ends of histogram of face image, determine the range of gray levels, and stretch the range of gray levels into the dynamic range of display device. Finally, we achieve illumination normalization and get the final face image. Unlike previous illumination normalization approaches, the method proposed in this paper does not require any training step or any knowledge of 3D face and reflective surface model. The experimental results using extended Yale face database B and CMU-PIE show that our method achieves better normalization effect comparing with the existing techniques.