Energy Technology Data Exchange (ETDEWEB)

To more accurately measure fluorescent signals from microarrays, we calibrated our acquisition and analysis systems by using groundtruth samples comprised of known quantities of red and green gene-specific DNA probes hybridized to cDNA targets. We imaged the slides with a full-field, white light CCD imager and analyzed them with our custom analysis software. Here we compare, for multiple genes, results obtained with and without preprocessing (alignment, color crosstalk compensation, dark field subtraction, and integration time). We also evaluate the accuracy of various image processing and analysis techniques (background subtraction, segmentation, quantitation and normalization). This methodology calibrates and validates our system for accurate quantitative measurement of microarrays. Specifically, we show that preprocessing the images produces results ...

UK PubMed Central (United Kingdom)

The use of digital wound images would allow remote consultation between patients, physicians, or other caregivers over the Internet. To evaluate the efficacy and validity of digital images for assessment...Full Text Available

CERN Document Server

Adaptive image processing is one of the most important techniques in visual information processing, especially in early vision such as image restoration, filtering, enhancement, and segmentation. This work focuses on applications of advanced CI techniques in image processing applications

Energy Technology Data Exchange (ETDEWEB)

As part of a larger elastic numerical modeling project, we have been investigating how energy reflected from steeply dipping interfaces is recorded using typical multicomponent acquisition geometries. Specifically, we have been interpreting how rcflection events from the flanks of salt dome structures are distributed on 3C and 4C phones for vertical seismic profiles (VSPs) and ocean bottom seismic (OBS) or land surface surveys. The ultimate goal of this investigation is to improve the structural imaging of steeply dipping interfaces and eventually to evaluate the usc of the recorded elastic wavefield for fluid description near these interfaces. In the current work, we focus on a common assumption used when processing converted wave reflection seismic data that most PP energy is recorded on the vertical geophone and/or the hydrophone and that most PS energy is recorded on the horizontal geophones. This is a useful assumption when it is ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of the Spatial Signature Analysis (SSA) Electrical-test (e-test) validation study that was conducted between February and June, 1998. SSA is an automated procedure developed by researchers at the Oak Ridge National Laboratory to address the issue of intelligent data reduction while providing feedback on current manufacturing processes. SSA was initially developed to automate the analysis of optical defect data. Optical defects can form groups, or clusters, which may have a distinct shape. These patterns can reveal information about the manufacturing process. Optical defect SSA uses image processing algorithms and a classifier system to interpret and identify these patterns, or signatures. SSA has been extended to analyze and interpret electrical test data. The algorithms used for optical defect SSA have been adapted and applied to e-test binmaps. An ...

CERN Document Server

Heterogeneous anisotropic diffusion problems arise in the various areas of science and engineering including plasma physics, petroleum engineering, and image processing. Standard numerical methods can produce spurious oscillations when they are used to solve those problems. A common approach to avoid this difficulty is to design a proper numerical scheme and/or a proper mesh so that the numerical solution validates the discrete counterpart (DMP) of the maximum principle satisfied by the continuous solution. A well known mesh condition for the DMP satisfaction by the linear finite element solution of isotropic diffusion problems is the non-obtuse angle condition that requires the dihedral angles of mesh elements to be non-obtuse. In this paper, a generalization of the condition, the so-called anisotropic non-obtuse angle condition, is developed for the finite element solution of heterogeneous anisotropic diffusion problems. ...

International Nuclear Information System (INIS)

The most important commercialized methods of attenuation correction in SPECT are based on attenuation coefficient map from a transmission imaging method. The transmission imaging system can be the linear source of radioelement or a X-ray CT system. The image of transmission imaging system is not useful unless to replacement of the attenuation coefficient or CT number with the attenuation coefficient in SPECT energy. In this paper we essay to evaluate the validity and estimate the error of the most used method of this transformation. The final result shows that the methods which use a linear or multi-linear curve accept a error in their estimation. The value of mA is not important but the patient thickness is very important and it can introduce a error more than 10 percent in the final result.

International Nuclear Information System (INIS)

Real-time neutron radiography (NTV) has been used for practical applications at the Kyoto University Reactor (KUR). At present, however, the direct image from the TV system is still poor in resolution and low in contrast. In this paper several image improvements are demonstrated, such as a frame summing technique, which are effective in increasing image quality in neutron radiography. Image integration before the A/D converter has a beneficial effect on image quality and the high quality image reveals details invisible in direct images, such as: small holes by a reversed image, defects in a neutron converter screen through a high quality image, a moving object in a contoured image, a slight difference between two low-contrast images by a subtraction ...

Energy Technology Data Exchange (ETDEWEB)

A real time neutron radiography system has been developed at the University of Michigan Phoenix Memorial Laboratory (PML) and has recently been used to test the imaging capabilities of a neutron imaging device developed by Lixi, Inc. of Downers Grove, Illinois. This device uses an input phosphor that is high in gadolinium to generate a light image which is then sent through an intensifier stage to provide images that can be viewed by eye, video camera, or standard 35 mm camera. It was determined that this device provides images of much higher resolution and sensitivity than those obtained with the imaging system currently being used at PML. Using computerized image enhancement techniques, the images obtained with the Lixi neutron imaging device can then be further enhanced or ...

International Nuclear Information System (INIS)

The image processing system for the dynamic neutron radiography has been developed. It is based on the hardware subset, composed by the method of the pipe-line and use of algorithm of local statistics. The processing speed per one pixel is shorter than 100 n sec and video-rate processing can be executed on it. Some image processes for improving the quality of the real-time neutron image, noise reduction and contrast stretching would be attempted by the use of this system. (author).

International Nuclear Information System (INIS)

SAFT-UT technology is shown to provide significant enhancements to the inspection of materials used in US nuclear power plants. This report provides guidelines for the implementation of SAFT-UT technology and shows the results from its application. An overview of the development of SAFT-UT is provided so that the reader may become familiar with the technology. Then the basic fundamentals are presented with an extensive list of references. A comprehensive operating procedure, which is used in conjunction with the SAFT-UT field system developed by Pacific Northwest Laboratory (PNL), provides the recipe for both SAFT data acquisition and analysis. The specification for the hardware implementation is provided for the SAFT-UT system along with a description of the subsequent developments and improvements. One development of technical interest is the SAFT real time processor. Performance of the real-time processor is impressive and comparison is made of this dedicated parallel processor to a ...

DEFF Research Database (Denmark)

The sources of non-white noise in Blood Oxygenation Level Dependent (BOLD) functional magnetic resonance imaging (fMRI) are many. Familiar sources include low-frequency drift due to hardware imperfections, oscillatory noise due to respiration and cardiac pulsation and residual movement artefacts not accounted for by rigid body registration. These contributions give rise to temporal autocorrelation in the residuals of the fMRI signal and invalidate the statistical analysis as the errors are no longer independent. The low-frequency drift is often removed by high-pass filtering, and other effects are typically modelled as an autoregressive (AR) process. In this paper, we propose an alternative approach: Nuisance Variable Regression (NVR). By inclusion of confounding effects in a general linear model (GLM), we first confirm that the spatial distribution of the various fMRI noise sources is similar to what has already been described in the ...

International Nuclear Information System (INIS)

MR images of steady and pulsatile disturbed flow, obtained with use of flow-compensated spin-echo (SE) and cine pulse sequences, revealed excellent flow visualization in three dimensions. Phantoms, built from molds of actual blood vessels, reproduced laminar, disturbed, or turbulent flow. Video recording (VR), performed under conditions equivalent to those of the MR experiments, showed separation zones identical to those seen on SE images. Pulsatile flow studies showed complex patterns of vortical flow on cine images and VR. Varying pulse sequence details changed contrast but not flow patterns. The validation of MR observations by VR has implications for clinical cine imaging and low abnormal signals observed on MR angiograms.

British Library Electronic Table of Contents (United Kingdom)

Magnetic resonance (MR) imaging and histopathology were used to diagnose an articular process synovial myxoma in a dog. On MR images, the tumor was characterized by distortion of the left L1-L2 articular process, widening of the articular process joint, and the presence of a mass contiguous with the synovium of the articular process that displaced the spinal cord. The tumor was T2-hyperintense, T1-hypointense, relative to muscle, and had mild contrast enhancement. The MR features of articular process synovial myxoma may be distinct from other diseases of the articular process joint.

Energy Technology Data Exchange (ETDEWEB)

Papers are presented in the areas of: Medical Technologies; Non-Destructive Evaluation; Applications of Signal/Image Processing; Laser Guide Star and Adaptive Optics; Computational Electromagnetic, Acoustics and Optics; Micro-Impulse Radar Processing; Optical Applications; TANGO Space Shuttle.

Energy Technology Data Exchange (ETDEWEB)

The impingement of a fluid jet onto a surface has broad applications across many industries. Within the UK nuclear industry, during the final stages of fuel reprocessing, impinging fluid jets are utilised to mobilise settled sludge material within storage tanks and ponds in preparation for transfer and ultimate immobilisation through vitrification. Despite the extensive applications of impinging jets within the nuclear and other industries, the study of two-phase, solid loaded, impinging jets is limited, and generally restricted to computational modelling. Surprisingly, very little fundamental understanding of the turbulence structure within such fluid flows through experimental investigation is found within the literature. The physical modelling of impinging jet systems could successfully serve to aid computer model validation, determine operating requirements, evaluate plant throughput requirements, optimise process operations and support ...

Energy Technology Data Exchange (ETDEWEB)

For many years, {beta} radioactivity has been used to label molecules and follow them in various biological processes. {beta} imaging is obtained by autoradiography. Classically made on films or on photographic emulsions, autoradiography is now supplanted by radio-imagers which are very performing. The phosphor-imager, {beta}-imager and {mu}-imager are the systems mainly used today and their operating principles and properties are compared. The great advantages of these imagers are: their rapidity to obtain results and their reliability for absolute quantification. All emitters ({beta}{sup -}, {beta}{sup -} -{gamma} and {beta}{sup +}) are detectable as well as the gamma emitters of nuclear medicine, by means of their low energy electrons ejected during y emission. Phosphor-imager is well suited to energetic tracers and ...

International Nuclear Information System (INIS)

In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable ...

International Nuclear Information System (INIS)

Fuji computed radiography (FCR) utilizing imaging plates stimulated by a scanning lazer has been developed in Japan and come to be widely available in diagnostic radiology. This system is advantageous because many processed images can be obtained with a single exposure. However, no reports have been published on the exact conditions necessary under which the FCR image processing method will produce improved visibility of pulmonary abnormal shadows on chest radiographs. In this report, chest FCR images obtained from 50 patients were analyzed, and the best practical image processing conditions were determined for each pathological state. Fundamental analysis was also performed for spatial and contrast resolution with FUNK chart and Burger's phantom using various thickness of acryl plate. Ninety ...

British Library Electronic Table of Contents (United Kingdom)

Even if there have been efforts to validate remote-sensing-based energy balance models, which provide evapotranspiration (ET) maps over a large spatial scale, few studies have been conducted to validate their performance in Korea. In this study, surface energy balance fluxes including ET were estimated and inter-compared with two different models using the Landsat-5 Thematic Mapper (TM) image over a watershed scale in Korea. While there were larger spatial discrepancies for net radiation, soil heat and sensible heat fluxes on a pixel-by-pixel basis between the two models, relatively smaller spatial discrepancies for the latent heat flux and daily ET were detected. The spatial discrepancies for the daily ET were larger in low topography and dense vegetation ranges. Despite the different par...

British Library Electronic Table of Contents (United Kingdom)

This paper introduces a parallel measurement approach for fast infrared-based human temperature screening suitable for use in a large public area. Our key idea is based on the combination of simple image processing algorithms, infrared technology, and human flow management. With this multidisciplinary concept, we arrange as many people as possible in a two-dimensional space in front of a thermal imaging camera and then highlight all human facial areas through simple image filtering, image morphological, and particle analysis processes. In this way, an individual's face in live thermal image can be located and the maximum facial skin temperature can be monitored and displayed. Our experiment shows a measured 1ms processing time in highlighting all human face areas. With a thermal imaging ca...

DEFF Research Database (Denmark)

Background:The validity of dementia diagnoses in the Danish nationwide hospital registers was evaluated to determine the value of these registers in epidemiological research about dementia. Methods: Two hundred patients were randomly selected from 4,682 patients registered for the first time with a dementia diagnosis in the last 6 months of 2003. The patients' medical journals were reviewed to evaluate if they fulfilled ICD-10 and/or DSM-IV criteria for dementia and specific dementia subtypes. The patients who were still alive in 2006 were invited to an interview. Results: One hundred and ninety-seven journals were available for review and 51 patients were interviewed. A registered diagnosis of dementia was found to be correct in 169 (85.8%) cases. Regarding dementia subtypes, the degree of agreement between the registers and the results of the validating process was low with a kappa of 0.36 (95% CI 0.24-0.48). Conclusion: ...

Energy Technology Data Exchange (ETDEWEB)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

Energy Technology Data Exchange (ETDEWEB)

In the presented case study CRS processing was able to improve the overall data quality of the processed lines in terms of signal-to-noise ratio and imaging. The complex geology is causing serious problems in conventional NMO/DMO processing that were solved by CRS processing. Even a depth processing with velocities calculated from CRS attributes gives good results similar to those from PreSDM in terms of the velocity field. Data quality of poststack depth migrated CRS stacks is even better than the image from PreSDM. (orig.)

Energy Technology Data Exchange (ETDEWEB)

Most of the tissue banks in the Asia Pacific region have been using ionising radiation at 25 kGy to sterilise human tissues for save clinical usage. Under tissue banking quality system, any dose employed for sterilisation has to be validated and the validation exercise has to be a part of quality document. Tissue grafts, unlike medical items, are not produced in large number per each processing batch and tissues relatively have a different microbial population. A Code of Practice established by the International Atomic Energy Agency (IAEA) in 2004 offers several validation methods using smaller number of samples compared to ISO 11137 (1995), which is meant for medical products. The methods emphasise on bioburden determination, followed by sterility test on samples after they were exposed to verification dose for attaining of sterility assurance level (SAL) of 10{sup -1}. This paper describes our ...

UK PubMed Central (United Kingdom)

Adaptive radiation therapy (ART) is the incorporation of daily images in the radiotherapy treatment process so that the treatment plan can be evaluated and modified to maximize the amount of radiation...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Ultrasound tomography is an attractive imaging method for the detection of breast cancer. The complex anatomy of the breast with its different spatial scales and material property contrasts make accurate reconstructions very challenging. This paper proposes a hybrid approach whereby Travel-of-Flight and Diffraction Tomography are combined together to achieve high-resolution and high-accuracy sound-speed reconstructions. The method is validated with several numerical phantoms.

Energy Technology Data Exchange (ETDEWEB)

In this paper, the multisource geoscientific data, such as TM data, NOAA data, the data of Bouguer gravity anomaly and aeromagnetic anomaly, the multisource geophysical processing methods, such as upward continuations, vertical derivative and gradient image, and synthetic image processing method - remote sensing image processing and geophysical image processing under I{sup 2}S600, are used to study the reverse faults or thrusts in the southern margin of Ordos basin, China. On the basis of these results and with geological investigation in the field, the authors have determined three thrust compression systems, named EW thrust compression system, NE thrust compression system and NW thrust compression system. These three systems reveal the regularity of geological structural evolution in the southern margin of Ordos basis ...

Energy Technology Data Exchange (ETDEWEB)

The biological treatment process was selected by Gaz de France (GDF), the French national gas utility, for the de-pollution of an old gas works where the main pollutants are coal tars containing polycyclic aromatic hydrocarbons. Microorganism-based biological treatment techniques may involve bio-reactors, static ground knolls (where oxygen is brought through drains) and dynamic knolls (where oxygenation is carried out by turning up the soil). Issues on sampling, sorting, process testing, site preparation, process control, etc. are reviewed

Energy Technology Data Exchange (ETDEWEB)

In order to understand the detail transient two-phase flow structure, more advanced two-phase flow instrumentation is required. One advanced technique for flow visualization is real-time neutron radiography. Reconstruction method of visualized radiographic image of liquid metal two-phase flow generated by the real-time neutron radiography system is proposed in this paper. Image processing techniques for noise reduction and image enhancement are discussed in detail. (author).

International Nuclear Information System (INIS)

The characteristics of real-time neutron radiography are described briefly in this paper, and the acquirement of neutron flux, the selection of convertor and the structure of the twilight imaging system and the image-sampling and image-processing system in SPRR-300 reactor are also analyzed detailedly. The experimental result of real-time neutron radiograph is too analyzed in this paper

International Nuclear Information System (INIS)

An imaging position sensitive detector for charged particles, neutrons, X-and gamma rays has been developed. The novel feature of this scintillation imaging radiation detector is its ability to detect individual nuclear particle scintillations with a h igh degree of spatial resolution. The key elements of this detector system are a high gain, low noise image intensifier tube, a CCD camera and commercially available image processing hardware and software. This detector system is highly effective for applications such as low fluence and real time neutron radiography, mapping of radioactive contamination in nuclear reactor fuel rods, X-ray diffraction imaging, high speed autoradiography and in general position sensitive detection of nuclear radiation. Results of some of the exploratory experiments carried out using this detector system are presented in this paper. ...

Energy Technology Data Exchange (ETDEWEB)

The authors have developed a high-sensitivity real-time neutron radiography (NR) system by the use of the low power reactor of Kinki University. The system was constructed with a high efficiency neutron-photon converter, an image intensifier and a SIT TELEVISION camera. Some digital image processing techniques were applied for improving the quality of the real-time neutron images. By the use of this system, dynamic neutron imaging was performed successfully under the condition of a weak neutron field that was about two orders of magnitude lower than that of the standard NR system. The neutron flux, calculated from the fluctuation of the neutron response of the images, was nearly equal to the value measured by the foil activation method. From this fact, the efficiency for the neutron detection of the imaging system was estimated to be almost ...

Energy Technology Data Exchange (ETDEWEB)

A rigorous mathematical model is developed to describe chemical absorption of carbon dioxide in a falling-film micro-contactor. Contrary to previous models described in literature, hydrodynamics in both phases is accurately captured by the Navier-Stokes equations. By this means, backmixing effects can be accounted for. Furthermore, the interface position is determined directly using the level-set method. The developed model is validated with experimental data obtained from literature and a good agreement is established. With the validated model, detailed studies are performed to investigate the impact of process parameters.

International Nuclear Information System (INIS)

The aim of this work is the implantation and characterization of a neutron radiography system that uses an electronic device for attainment of images in real time, for its implementation in the nuclear research reactor Argonauta at IEN/CNEN (Nuclear Engineering Institute of the Brazilian Nuclear Energy Commission). The Electronic Imaging System in Real Time is composed by a scintillator screen for neutron, a video camera (CCD), a digital plate and a computer with specific computational programs for digital processing of the images. The System in installed real time is apt to carry through neutron radiography inspections of static and dynamic events of several types of samples. (author)

Energy Technology Data Exchange (ETDEWEB)

In order to improve the image quality of linear tomography performed with the Fuji Computed Radiography (FCR) system, we have examined one-dimensional unsharp mask filtering to reduce blur formed in the direction of tomographic swing. We determined a mask size and a weighting factor of the image processing suitable to obtain a quality tomogram. The mask size of 41 x 1 pixels for a 14 x 14'' imaging plate, which modifies the original image date and results in demonstrating a peak frequency at 0.2 cycles/mm for spatial frequency spectrum, is superior in showing fine vessel structures and morphological features of pathology in the lung fields. An additional spatial frequency filtration in the direction perpendicular to the tomographic movement reduces the blur and clearly demonstrates object contours running parallel to the tube movement. However, the additional ...

Energy Technology Data Exchange (ETDEWEB)

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead-bismuth eutectic was used as a working fluid. Particles made from a gold-cadmium intermetallic compound (AuCd{sub 3}) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than l/e and the particle size of the tracer was larger than one image element size digitized for the image processing. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Computer vision imposes unique requirements on the representation and manipulation of image data and knowledge. At a vision system's lowest level are sensors that represent an image with purely numeric image arrays, while at the highest level are semantic world models that provide the final interpretation of the scene. In between are thousands of intermediate descriptions, many of which must be repeatedly accessed and processed during interpretation. In this article, the authors describe a representation and management system for use at the intermediate (symbolic) level of vision. Based on database management methodology, the intermediate symbolic representation (ISR) mediates access to intermediate-level vision data and forms an active interface to the higher-level inference processes that construct an image's interpretation. The system ...

International Nuclear Information System (INIS)

Chest radiograms obtained by using Fuji Computed Radiography (FCR) system were compared to conventional film/screen radiograms. The FCR images showed better image quality in diagnostic information than the conventional chest images. In FCR, the radiation exposure to patient for chest examination could be reduced up to one tenths of conventional chest examination. The main advantages or FCR were considered to depend on the contrast processing and frequency processing properties. The use of FCR in clinical work may improve both diagnostic quality and radiation exposure.

Energy Technology Data Exchange (ETDEWEB)

Quantitative digital imaging, using planar laser light scattering techniques is being developed for the analysis of turbulent and reacting flows. Quantitative image data, implying both a direct relation to flowfield variables as well as sufficient signal and spatial dynamic range, can be readily processed to yield two-dimensional distributions of flowfield scalars and in turn two-dimensional images of gradients and turbulence scales. Much of the development of imaging techniques to date has concentrated on understanding the requisite molecular spectroscopy and collision dynamics to be able to determine how flowfield variable information is encoded into the measured signal. From this standpoint the image is seen as a collection of single point measurements. The present effort aims at realizing necessary improvements in signal and spatial dynamic range, ...

International Nuclear Information System (INIS)

In spite of the improved imaging techniques currently available, mortality for pancreatic cancer is still high, and pancreatics is often diagnosed only in its advanced stages. The authors investigated the value of different imaging techniques - i.e., US, CT, and ERCP - for an early diagnosis, when a more effective (curative?) treatment can be suggested. Fifty-six cases of pancreatic cancer and 36 cases of chronic pancreatitis were evaluated. The results indicate that ERCP, with the help of statistical methods, is superior to US and CT not only in evaluating early neoplastic or inflammatory lesions, but also for their differential diagnosis. In the letter case, ERCP can sometimes be used as a valid alternative to fine-needle aspiration biopsy.

Science.gov (United States)

An improved method of generating angle-domain common-image gathers (ADCIGs) by VSP reverse time migration (RTM) is introduced in this paper. The formula which is used to compute the receiver wavefield for VSP RTM is modified by adding an amplitude correction term in order to conveniently output amplitude-preserved ADCIGs. Compared with the surface seismic data, VSP data contains much richer wavefields. However, the direct and downgoing waves can bring about serious imaging artifacts in ADCIGs, especially the direct wave. The feasibility and validity of this method is demonstrated by both numerical and real VSP data from western China. Thus, the ADCIGs from this method can provide reliable basic data for VSP migration velocity analysis, VSP AVO/AVA analysis, and inversion.

International Nuclear Information System (INIS)

The neutron radiography system installed at the E-2 experimental hole of the KUR (Kyoto University Reactor) has been used for some NDT applications in the nuclear field. The on-line video image processing system of this facility is introduced in this paper. A 0.5 mm resolution in images was obtained by using a super high quality TV camera developed for X-radiography viewing a NE-426 neutron-sensitive scintillator. The image of the NE-426 on a CRT can be observed directly and visually, thus many test samples can be sequentially observed when necessary for industrial purposes. The video image signals from the TV camera are digitized, with a 33 ms delay, through a video A/D converter (ADC) and can be stored in the image buffer (32 KB DRAM) of a microcomputer (Z-80) system. The digitized pictures are taken with 16 levels of gray scale and resolved to 240 x 256 ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a 1993 field experiment entitled Marine Aerosol Properties and Thermal Imager Performance Trial (MAPTIP) conducted by NATO AC/243 Panel 04/RSG.8 and 04/RSG.5 in the Dutch coastal waters. Objectives were: to improve and validate vertical marine aerosol models by providing an extensive set of aerosol and meteorological measurements, within a coastal environment at different altitudes and for a range of meteorological conditions; make aerosol and meteorological observations in the first 10 m of the ocean surface with a view to extending existing aerosol models to incorporate near-surface effects; and to assess marine boundary layer effects on thermal Imaging systems. Aerosol and meteorological instruments, as well as thermal imagers and calibrated targets, were utilized. This network of instrumentation has provided a comprehensive database of aerosol size distribution profiles and ...

International Nuclear Information System (INIS)

The validation of the forecast model for early emergency response to nuclear accidents is evaluated by trace tests in atmosphere in Daya Bay nuclear power site. The simulation experiment of the Daya Bay nuclear power site shows that the particle spreading image and the time-integrated concentration distribution given by plume concentration prediction model can perform the variation of pathway of the pollutant transport, as well as the effects of topography on transport and diffusion of pollutants. The simulation of five trace tests in field shows that 59.1% of ratios between predicted results and observed results are within the range of 10, and 41% of ratios are within the range of 5 approximately. (authors)

Energy Technology Data Exchange (ETDEWEB)

The real-time neutron radiography system of the Kyoto University Reactor (KUR) has been practically applied to penetrating the side plates containing boron burnable poison to test MTR type reactor fuels and to investigation of moving objects. Compared with the image obtained by the direct film method, however, the image from the TV system is in low-contrast and poor-resolution. This paper presents some digital processing approaches to improve the image quality and the neutron TV system is successfully applied to neutron computed tomography (NCT). The frame summing technique is effective to increase the quality of the radiographic image. By using the NTV system in NCT, the projection data are able to be acquired in a single measurement as observing the projection image on a CRT monitor. Two weighting functions based on the Fourier-convolution algorithm are ...

Science.gov (United States)

We describe a closed-loop brain-computer interface that re-ranks an image database by iterating between user generated 'interest' scores and computer vision generated visual similarity measures. The interest scores are based on decoding the electroencephalographic (EEG) correlates of target detection, attentional shifts and self-monitoring processes, which result from the user paying attention to target images interspersed in rapid serial visual presentation (RSVP) sequences. The highest scored images are passed to a semi-supervised computer vision system that reorganizes the image database accordingly, using a graph-based representation that captures visual similarity between images. The system can either query the user for more information, by adaptively resampling the database to create additional RSVP sequences, or it can converge to a 'done' state. The done ...

Energy Technology Data Exchange (ETDEWEB)

VSP reverse-time migration is a well adaptable wave equation migration method. Its control equation not only describes all-direction propagation of seismic wave but also removes interbed multiples. Clearbout's image principle is generalized to determine image conditions, real VSP data are used to determine boundary condition, and two way reflection-free wave equation is solved by making reverse-time extrapolation. In each step of extrapolation, the migration value at relevant image point is obtained by using the image condition. The complete migration of a seismic section is achieved when reverse-time extrapolation reaches the minimum image time. In this paper it is proved theoretically and practically that this method is applicable to any velocity variation and makes the migrated section have both good resolution and high S/N ratio. Besides, this method results in high ...

British Library Electronic Table of Contents (United Kingdom)

In the autonomous unmanned helicopter landing problem, the position of the unmanned helicopter relative to the landmark is very important. A camera carried on the unmanned helicopter can capture an image of the landmark. In earlier research, it was reported that the camera position could be estimated by features extracted from the landmark image. However, it is necessary that the landmark image should be complete, or with only slight deficiencies, in order for this estimation process to be possible. In this article, we report on an innovative design for an estimation made from a camera position giving an incomplete single image of the landmark. An adaptive neuro-fuzzy inference system (ANFIS) is used to construct the mapping relation between the features of complete and incomplete landmark...

International Nuclear Information System (INIS)

Conventional Radiography, Fuji Computed Radiography (FCR) hardcopy and CRT images were evaluated about the detectability of pulmonary nodule using the chest phantom. Conventional and digitized chest radiographs (FCR) were used, including 45 normal cases and 45 abnormal cases with a variety pulmonary nodule. Observer performance tests were conducted to compare the effects on diagnostic accuracy of Conventional Radiography, FCR hardcopy and CRT images, and diagnostic accuracy was determined with receiver operating characteristic (ROC) analysis. ROC study was performed in which six radiologists were asked to locate nodule on three modalities. Two CRT monitors were used to observed CRT images. The left side CRT monitor was divided into two parts and displayed two images which were done as same image processing as FCR hardcopy. The right side CRT monitor was divided ...

International Nuclear Information System (INIS)

A computer controlled digital system, Fuji Computed Radiography (FCR) is capable of providing more stable output image than conventional screen/film system. So FCR would be an ideal system for the detection of pneumoconiosis due to the constant high quality of the output films. We tried to find the optimum image processing to compensate the small size (1/2 in length of a full-size radiograph) of the output image of digital radiography. The best result for FCR was given with gamma 0.85 and 0.30 enhancement of response at spatial frequency of 0.085 cycle/mm. On the other hand, the digitally processed FCR size ILO standard films, the characteristics of which is different from FCR output films, proved to be most preferable when the image processing is made with gamma 0.85 and 0.25 enhancement at spacial frequency of 0.17 cycle/mm. If the above ...

CERN Document Server

Methods and Procedures for the Verification and Validation of Artificial Neural Networks

Energy Technology Data Exchange (ETDEWEB)

Digital imaging techniques such as Digital Image Intensifier Radiography and Digital Storage Phosphor (Selenium) Radiography are replacing conventional film-screen radiography more and more. The aim of this development is the extension of diagnostic capabilities and the reduction of side effects such as radiation dose. Conventional film-screen radiography and digital radiography are very different ways of imaging. For digital radiography specific post-processing is the link between imaging conditions and film documentation. Optimisation of the images includes new possibilities of post-processing and a broad range for variation of the dose. Especially in fluoroscopy, dose can be reduced significantly by new technical features like pulsed fluoroscopy. For digital radiography the European guidelines on quality criteria have to be applied to ...

Science.gov (United States)

Heterogeneous gasless reactive systems, including high-energy density metal-nonmetal compositions, have seen increasing study due to their various applications. However, owing to their high reaction temperature, short reaction time, and small scale of heterogeneity, investigation of their reaction mechanisms and kinetics is very difficult. In this study, microstructural changes and the kinetics of product layer growth in the W-Si system was investigated using a high-speed x-ray phase-contrast imaging technique. Using the Advanced Photon Source of Argonne National Laboratory, this method allowed direct imaging of irreversible reactions in the W-Si reactive system at frame rates up to 36 000 frames per second with 4 {mu}s exposure and spatial resolution of 10 {mu}m. Details of the Si melt and reactions between W and Si, that are unable to be viewed with visible-light imaging, were revealed. These include ...

Energy Technology Data Exchange (ETDEWEB)

In an effort to evaluate the feasibility of introducing computed radiography (FCR) into mass screening for lung cancer, the ability of FCR to detect nodules one cm in diameter was examined using a humanoid chest phantom. Based on the receiver operating characteristic (ROC) analysis, the detectability of FCR was compared with that of conventional radiography and photofluorography. The values of area under ROC curves were higher for FCR (0.963 for image similar to that with conventional film-intensifying screen system, image A; and 0.952 for processed image, image B) than the other two methods (0.774 for radiography and 0.789 for photofluorography). Degradation of image quality in FCR could be avoided by a wide latitude even if proper exposure techniques might not be employed. Images A and B in FCR yielded excellent delineation for nodules in ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes Fuji computed radiography (FCR) of Fuji Film for NDT (non-destructive testing). Imaging plate (IP) is a two-dimensional detector of X-ray, and shows higher photographic sensitivity than X-ray film. The output emission of IP provides a good linear relationship to X-ray intensity in a wide intensity range. When this emission can be digitized, the X-ray intensity can be also digitized. IP is applied to NDT as an inspection using X-ray. FCR provides higher photographic sensitivity than the conventional X-ray film method, which results in one-fifth to one-twentieth of irradiation time. Images with stable density can be obtained independent of the intensity. Since IP has a wide dynamic range, the variation of X-ray intensity of 1:500 can be expressed in a single image by single shot. High density record including 1000 images can be done using a 5.25 inch optical disk through the digital ...

International Nuclear Information System (INIS)

Several neutron radiography systems designed to view transient processes on a real-time basis have been developed. With the advent of these different real-time systems comes the necessity to develop a means to quantitatively evaluate and compare these systems. A suitable method for measuring the resolution capabilities of the image-forming system is the determination of the modulation transfer function (MTF). The MTF is a measure of an imaging system's ability to reproduce the spatial frequencies present in an image. The system in use at the University of Missouri Research Reactor is described. (Auth.).

Energy Technology Data Exchange (ETDEWEB)

The current role of magnetic resonance imaging (MRI) in different organ systems is discussed and compared to nuclear medicine and to other available clinical diagnostic modalities. The value of optimizing radiofrequency pulse sequence selection to provide additional tissue characterization is also described. The results of nuclear medicine and MRI studies in 56 patients are compared to evaluate the clinical diagnostic contribution of each imaging modality for various pathological processes. In addition, the state-of-the-art MRI systems and future development in MRI technology with its potential contribution is defined.

Energy Technology Data Exchange (ETDEWEB)

CuAg core-shell nanoparticles are synthesized by ultra-high vacuum thermal evaporation. We show on this system how the Energy-Filtered Transmission Electron Microscopy (EFTEM) technique allows one to improve the characterization by precisely pointing out the formation of core-shell arrangements in bimetallic nanoparticle assemblies. A criterion to measure the shell thickness from EFTEM images on unique core-shell nanoparticles is defined, that can be used for core-shell nanoparticles of any sizes, with shell thicknesses over 1 nm. It is based on the intensity variation along a line drawn across a core-shell nanoparticle on a EFTEM image. This criterion has been validated by a close comparison of the shell thickness measurements performed in this work and the ones obtained by acoustic micro-Raman spectroscopy. Using this criterion, we report a strong correlation between the size of the Cu cores and the formation of the ...

Energy Technology Data Exchange (ETDEWEB)

Certification as applied to existing computer codes includes the verification and validation process, placing the code in configuration control, establishing user qualification standards and training requirements. All software intended for use in critical calculations must be certified. This report is intended to fulfill the requirements for the certification of the SHIELD, SHLDED, GEDIT, GENPRT, FIPROD, FPCALC, and PROCES modules of the SHIELD system built February, 1992, by W.S. Parks. These modules are used for burnup, cooling, separate, and edit calculations.

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The application of a Compact Airborne Spectrographic Imager to assessment and monitoring of lakes in a lignite open cast mining area in central Germany is described. The imager was used in combination with additional ground experiments, such as field spectroscopy and water sampling. The spectral characteristics of an instrument under development for monitoring geochemical and hydrological processes are presented. Summary form only.

Wastenet

...) Abstract: Fluorescence microscopic imaging is widely used in biomedical research to study molecular and cellular processes in cell culture or tissue samples. This is motivated by the high inherent sensitivity of fluorescence techniques, the spatial resolution that compares favorably with cellular dimensions, the stability of the fluorescent labels used and the sophisticated strategies that have been developed for selectively labeling target molecules. More recently, two and ...

Energy Technology Data Exchange (ETDEWEB)

In this paper, the adaptive optics (AO) system at Keck Observatory is characterized. The AO system is described in detail. The physical parameters of the lenslets, CCD and deformable mirror, the calibration procedures and the signal processing algorithms are explained. Results of sky performance tests are presented: the AO system is shown to deliver images with an average Strehl ratio of up to 0.37 at 1.59 {micro}m using a bright guide star. An error budget that is consistent with the observed image quality is presented.

International Nuclear Information System (INIS)

Medical imaging using single gamma-ray-emitting radionuclides typically makes use of parallel hole collimators or pinholes in order to achieve good spatial resolution. However, a tradeoff in sensitivity is inherent in the use of a collimator, and modern preclinical single photon emission computed tomography (SPECT) systems detect a very small fraction of emitted gamma rays, often less than 0.1%. A system for small animal SPECT imaging which uses no collimators could potentially achieve very high sensitivity-several tens of percent-with reasonably sized detectors. This would allow two significant improvements in preclinical studies: images could be obtained more rapidly, allowing higher throughput for screening applications, or for dynamic processes to be observed with very good time resolution; and images could be obtained with less radioactive tracer, making possible the in vivo ...

Energy Technology Data Exchange (ETDEWEB)

Gel dosimetry is a new dosimetry method applied in radiation therapy. Gel dosimeters consist of a radiation sensitive gel, which can integrate absorbed doses from several radiation sources or beams. The dose to the gel can be evaluated by magnetic resonance imaging (MRI), a procedure that is the focus of the present thesis. A robust tool for the evaluation of the nonuniformity in MRI has been developed, the Deviation Image method. Unlike previously presented methods, the Deviation Image method includes all nonuniformity variations across a phantom surface and is insensitive to stochastic noise. Methods for the estimation of stochastic noise were analyzed in terms of sensitivity to nonuniformities. A method that averages the stochastic noise level over five regions over the phantom surface, and a method that assesses the stochastic noise level from the background, were found to be the methods of choice. Pronounced MR ...

UK PubMed Central (United Kingdom)

Background and AimsXylem vessels containing gases (embolized) must be refilled with water if they are to resume transport of water through the plant, so refilling is of great importance...Full Text Available

UK PubMed Central (United Kingdom)

In Diffusion Tensor Magnetic Resonance Image (DT-MRI) processing a 2^nd order tensor has been commonly used to approximate the diffusivity function at each lattice...Full Text Available

UK PubMed Central (United Kingdom)

Accurate segmentation of tissue microarrays is a challenging topic because of some of the similarities exhibited by normal tissue and tumor regions. Processing speed is another consideration...Full Text Available

Science.gov (United States)

We propose a quantum secure direct communication scheme based on non-orthogonal entangled pairs and local measurement. In this scheme, we use eight non-orthogonal entangled pairs to act as quantum channels. Due to the non-orthogonality of the quantum channels, the present protocol can availably prohibit from all kinds of valid eavesdropping and acquire a secure quantum channel. By local measurement, the sender acquires a secret random sequence. The process of encoding on the random sequence is identical to the one in one-time-pad. So the present protocol is secure. Even for a highly lossy channel, our scheme is also valid. The scheme is feasible with present-day techniques.

International Nuclear Information System (INIS)

The objective of this project is to develop multi-dimensional computational models in order to improve the operation of uranium electrorefiners currently used in pyroprocessing technology. These 2-D (US) and 3-D (ROK) mathematical models are based on the fundamental physical and chemical properties of the electrorefiner processes. The validated models by compiled and evaluated experimental data could provide better information for developing advanced electrorefiners for uranium recovery. The research results in this period are as follows: - Successfully assessed a common computational platform for the modeling work and identify spatial characterization requirements. - Successfully developed a 3-D electro-fluid dynamic electrorefiner model. - Successfully validated and benchmarked the two multi-dimensional models with compiled experimental data sets

Energy Technology Data Exchange (ETDEWEB)

A section of the northern margin of the Guineo-Congolian rain forest of the Central African Republic is studied to determine to what extent deforestation is evolving. Three sites are presented to highlight the diversity in local environmental settings at the northern margin of the closed equatorial rain forest: the contiguous equatorial rain forest, the boundary between the closed rain forest and the grasslands, and a predominantly secondary grassland environment. Proven image processing procedures for determining land cover and vegetation vigor were applied to Landsat MSS data to determine land cover characteristics and identify alterations in land cover that indicate potentially degraded forest environments. Land cover was independently assessed using spectral signatures determined from a statistical clustering routine. The images presented and image analyses contribute insights and information to an ...

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is the implantation and characterization of a neutron radiography system that uses an electronic device for attainment of images in real time, for its implementation in the nuclear research reactor Argonauta at IEN/CNEN (Nuclear Engineering Institute of the Brazilian Nuclear Energy Commission). The Electronic Imaging System in Real Time is composed by a scintillator screen for neutron, a video camera (CCD), a digital plate and a computer with specific computational programs for digital processing of the images. The System in installed real time is apt to carry through neutron radiography inspections of static and dynamic events of several types of samples. (author)

International Nuclear Information System (INIS)

Forty-seven subtraction images of FCR were compared with subtraction images of conventional angiography of the head. Quality of the FCR images were equal or superior to that of conventional angiography. Antero-posterior projection of external carotid arteriography by FCR was most useful because of its wide dynamic range. As contrast resolution of FCR is superior to that of conventional angiography, only half diluted contrast media was needed. As for spacial resolution, FCR is slightly inferior to conventional angiography. However, most vessels which are clinically important were adequately demonstrated. A weak point of FCR which should be improved is relatively long time to process the images after radiation exposure. (author).

British Library Electronic Table of Contents (United Kingdom)

There is proposed the nonlinear model of dose dependence saturation of the yield strength on the base of the vacancy and interstitial barrier interaction in this work. Processes of mutual recombination of vacancy and interstitial barriers and formation of vacancy and interstitial clusters are taken into consideration. In the framework of the model, the analytical equations corresponding to the evolution of the barrier densities and yield strength are obtained. It is shown that the yield strength of irradiated materials decreases with the increasing intensity of barrier recombination processes, the dependence being nonlinear. Also it is shown that the model is valid both for low doses and large doses on the stage of radiation hardening.

British Library Electronic Table of Contents (United Kingdom)

We propose unsteady-state reverse osmosis cell modelling in two dimensions. The convection-diffusion equation describing the concentration of the relevant chemical species is solved by a finite difference technique, while the velocity field is described by empirical expressions for spiral-wound membrane cells. A non-constant permeability is introduced to take into account the effects of membrane compaction at high operating pressures. The role of concentration polarization is discussed for different values of the parameters describing the global process. Finally, the model is applied to predict the effects of a pulsating flow where a cyclic pressure feed is adopted to enhance the permeate flux. In this context, an experimental validation of the model is proposed.

International Nuclear Information System (INIS)

The long and resource intensive process of drug discovery and development is confronted with the basic challenge of providing effective and safe therapies at reasonably low costs. The better the mechanism of a disease is known, the higher the probability to find an appropriate therapy. Also, the better and earlier a disease can be diagnosed and characterized, the higher the chance to be able to interfere in this process with a chemical entity. This reasoning sets the framework for the use of imaging in drug discovery. We discuss the relevance of magnetic resonance imaging and spectroscopy to derive anatomical, functional, metabolic and target-related information in the context of pharmacological research in vivo. (author)

Energy Technology Data Exchange (ETDEWEB)

Neutron radiography has been put to practical use in foreign countries as one of nondestructive inspection technologies, but in Japan, its application to other scientific fields is mainly researched. The reason is, the neutron radiography apparatuses installed in Japan are hard to be industrially utilized for a number of reasons, but also the characteristics of neutron radiography are not clearly established, and it is not standardized. The part from a collimator through an object to a detector is called ``upstream``, the part of an image detector is called ``midstream``, and the part of image processing is called ``downstream``. The nonparallel property of beam, image distortion and the lack of sharpness, beam quality and the interaction of neutron beam with an object are discussed about the upstream. The intensity of neutron beam, the energy spectra, the effective total macroscopic cross section, the ...

Energy Technology Data Exchange (ETDEWEB)

The present paper is concerned with development and application of a so-called Effective Convection Model (ECM), which aims to provide a detailed, mechanistic description of heat transfer processes in a BWR lower plenum. The ECM is a Computational Fluid Dynamics (CFD)-like tool which employs a simpler and more effective approach to compute heat transfer by solving only energy conservation equation instead of solving the full set of Navier-Stokes and energy equations by a CFD code. We implement the ECM in a CFD code (Fluent), with detailed description of the ECM development, implementation and validation. A dual approach is used to validate the ECM, namely validation against experimental data and against heat transfer results obtained by CFD predictions in the same geometries and conditions. Insights gained from CFD simulations are also used to improve ECM. The ECM capability as an effective tool to ...

International Nuclear Information System (INIS)

Particularly high coherence of the x-ray beam is associated, on the ID19 beamline at ESRF, with the small angular size of the source as seen from a point of the sample (0.1-1 #mu#rad). This feature makes the imaging of phase objects extremely simple, by using a 'propagation' technique. The physical principle involved is Fresnel diffraction. Phase imaging is being simultaneously developed as a technique and used as a tool to investigate light natural or artificial materials introducing phase variations across the transmitted x-ray beam. They include polymers, wood, crystals, alloys, composites or ceramics, exhibiting inclusions, holes, cracks, ... . 'Tomographic' three-dimensional reconstruction can be performed with a filtered back-projection algorithm either on the images processed as in attenuation tomography, or on the phase maps retrieved from the images with a reconstruction ...

Energy Technology Data Exchange (ETDEWEB)

This paper briefly describes an industrial application of the foam decontamination process applied to large volume components. The process is based on the filling of the component with liquid foam containing suitable chemical reagents, and a circulation loop enables its continuous recycling. The process was successfully validated during the decontamination of a graphite gas-cooler representing a developed area of 1000 m{sup 2}. A decontamination factor up to 190 was obtained leading to a residual activity below 1 Bq/cm{sup 2}. The process only produced 6 m{sup 3} of effluent i.e. about ten times less than for a chemical solution technique. (authors) 2 refs.

Energy Technology Data Exchange (ETDEWEB)

Accurate automated alignment of laser beams in the National Ignition Facility (NIF) is essential for achieving extreme temperature and pressure required for inertial confinement fusion. The alignment achieved by the integrated control systems relies on algorithms processing video images to determine the position of the laser beam images in real-time. Alignment images that exhibit wide variations in beam quality require a matched-filter algorithm for position detection. One challenge in designing a matched-filter based algorithm is to construct a filter template that is resilient to variations in imaging conditions while guaranteeing accurate position determination. A second challenge is to process the image as fast as possible. This paper describes the development of a new analytical template that captures key recurring features present in ...

International Nuclear Information System (INIS)

Early white matter (WM) injury affects brain maturation in preterm infants as revealed by diffusion tensor imaging and volumetric magnetic resonance (MR) imaging at term postmenstrual age (PMA). The aim of the study was to assess quantitatively brain maturation in preterm infants with and without milder forms of WM damage (punctate WM lesions, PWML) using conventional MRI. Brain development was quantitatively assessed using a previously validated scoring system (total maturation score, TMS) which utilizes four parameters (progressive myelination and cortical infolding, progressive involution of glial cell migration bands and germinal matrix tissue). PWML were defined as foci of increased signal on T1-weighted images and decreased signal on T2-weighted images with no evidence of cystic degeneration. A group of 22 preterm infants with PWML at term PMA (PWML group) were compared with ...

International Nuclear Information System (INIS)

The PERMCAT process chosen for the final clean-up stage of the Tokamak Exhaust Processing system of the ITER tritium plant combines in a single component a catalytic reactor and a permeator using Pd/Ag membranes. This study covers the mechanical behaviour of a Pd/Ag membrane under different operating conditions. The consequences of hydrogen uptake by the membrane during nominal operation but also during off-normal events are presented. Depending on the operating conditions, expansions around 2% and significant deformations are observed. Different mechanical designs of PERMCAT reactors are then discussed. The first generation comprises finger-type membranes and two new mechanical designs use either additional edge welded bellows or a special corrugated Pd/Ag membrane. These upgraded designs improve the robustness and simplify the geometry of the component. The experimental validation of these new units has been carried out ...

Energy Technology Data Exchange (ETDEWEB)

To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human ...

CERN Document Server

We describe features of the LSST science database that are amenable to scientific data mining, object classification, outlier identification, anomaly detection, image quality assurance, and survey science validation. The data mining research agenda includes: scalability (at petabytes scales) of existing machine learning and data mining algorithms; development of grid-enabled parallel data mining algorithms; designing a robust system for brokering classifications from the LSST event pipeline (which may produce 10,000 or more event alerts per night); multi-resolution methods for exploration of petascale databases; indexing of multi-attribute multi-dimensional astronomical databases (beyond spatial indexing) for rapid querying of petabyte databases; and more.

Energy Technology Data Exchange (ETDEWEB)

Forests on the Kola Peninsula in Northern Russia grow close to the northern tree line. They are subjected to both natural and anthropogenic stress factors. The Cu-Ni smelter 'Severonikel' (Lat. 67 deg 55'N; Long. 32 deg 57'E) near Monchegorsk is one of the two major sources of sulphur dioxide and heavy metals emissions on the Kola Peninsula. These emissions have caused significant deterioration of the surrounding vegetation. The thesis demonstrates how methods of Remote sensing, ground survey and mathematical modelling can be integrated for monitoring of the smelter's environmental impact on the surrounding vegetation: ground truth data are used for calibration of remote-sensed data, which further serve to verify mathematical models. The study aims were: * to estimate the scale of airborne sulphur pollution from the smelting industry on the Kola Peninsula and its effect on vegetation; * to assess spatial extent of the forest decline in the ...

Science.gov (United States)

BackgroundIn recent years, near-infrared fluorescence (NIRF)-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area.ResultsThis study manufactured 12-nm DMSA-coated Fe3O4 ...

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The groundwater flow and transport model of the Faultless underground nuclear test conducted at the Central Nevada Test Area (CNTA) was accepted by the state regulator and the environmental remediation efforts at the site have progressed to the stages of model validation and long-term monitoring design. This report discusses the long-term monitoring strategy developed for CNTA. Subsurface monitoring is an expensive and time-consuming process, and the design approach should be based on a solid foundation. As such, a thorough literature review of monitoring network design is first presented. Monitoring well networks can be designed for a number of objectives including aquifer characterization, parameter estimation, compliance monitoring, detection monitoring, ambient monitoring, and research monitoring, to name a few. Design methodologies also range from simple hydrogeologic intuition-based tools to sophisticated statistical- and ...

British Library Electronic Table of Contents (United Kingdom)

Subject of this study is the question of whether cone beam CT (CBCT) images with reduced projection data are suitable for use in adaptive radiation therapy (ART) treatment planning. For this purpose image quality and dose calculation accuracy depending on imaging modality were analysed. In this context, two CBCT-methods will be indicated having reduced projection data sets: Scans acquired with 200^o rotation angle in order to accelerate the CBCT process (half scan), or scans with an asymmetric cone beam and detector offset, used to enlarge the field-of-view (half fan). Methods: For three different CBCT-modes (On-Board-Imaging, Varian Medical Systems), two of them based on reduced projection data, and a conventional multidetector CT system, the main image quality parameters were studied. Tr...

International Nuclear Information System (INIS)

A real-time neutron radiography system was installed at the neutron radiography facility of Sumitomo Heavy Industries where a sub-compact cyclotron is used as a neutron generator and nominal neutron flux was observed as 1.1 x 10"6 n/cm"2/sec. Preliminary tests were made for various kinds of such components as collimators, scintillators, cameras and lenses and the system was chosen to give the highest quality images. Especially for the scintillator screen, screening tests were carried out for compounds of LiF/ZnS(Ag) and Gd_2O_3/ZnS(Ag) by radiographic film method. The neutron radiography image was converted to fluorescent images by means of the converter and observed by a SIT type TV camera. The video signal was directly displayed on a CRT or after processed with digital image processing devices. The characteristics of this system as for the resultant resolution ...

International Nuclear Information System (INIS)

Present day mammography has not been able to make use of the advantages of digital luminescence radiography because of the limited spatial resolution. The recent development of electromagnetic focusing X-ray tube with effective focal spot sizes from 0.04 to 0.12 mm allows radiographic direct magnification with less geometric blur. It is now possible to combine direct magnification mammography with digital luminescence radiography. By combining high quality storage phosphor screens with an HQ-workstation a spatial resolution of 8 lp/mm is possible for 1.7-fold magnification. For 4-fold spot magnification views spatial resolution can be theoretically increased to approx. 20 lp/mm. One important advantage of digital radiography is the possibility of image-postprocessing. This article presents two sets of standard parameters and three sets of image dependent parameters for better imaging of specific lesions, such as ...

Energy Technology Data Exchange (ETDEWEB)

Current projections of the response of the biosphere to global climatic change indicate as much as 50% to 90% spatial displacement of extratropical biomes. The mechanism of spatial shift could be dominated by either (1) competitive displacement of northern biomes by southern biomes, or (2) drought-induced dieback of areas susceptible to change. The current suite of global biosphere models cannot distinguish between these two processes, thus determining the need for a mechanistically based biome model. The model is in an early stage of development and will require several enhancements, including explicit simulation of potential evapotranspiration, extension to boreal and tropical biomes, a shift from steady-state to transient dynamics, and validation on other continents.

International Nuclear Information System (INIS)

This report has been prepared in support of the industry effort to standardize nuclear plant designs. This document describes the Combustion Engineering, Inc. System 80+trademark Standard Design. This volume contain Chapter 18 -- Human Factors Engineering. Topics covered include: design team organization and responsibilities; design goals and design bases; design process and application to human factors engineering; functional task analysis; control room configuration; information presentation and panel layout evaluation; control and monitoring outside the main control room; and verification and validation.

Energy Technology Data Exchange (ETDEWEB)

The development of detailed chemical kinetic reaction mechanisms for analysis of autoignition and knocking of hydrocarbon fuels is described. In particular, kinetic processes of concern for the oxidation of complex hydrocarbon fuel molecules are emphasized. The wide ranges of temperature and pressure which are encountered by end gases in automobile engine combustion chambers result in extreme demands on reaction mechanisms which are intended to describe knocking conditions and predict rates of combustion and ignition. The reactions and chemical species which are most important in each temperature and pressure regime are discussed, and the validation of these reaction mechanisms through comparison with idealized experimental results is described. 53 refs., 8 figs., 5 tabs.

Energy Technology Data Exchange (ETDEWEB)

The validity of the Big Bang theory is evaluated. The basis of the Big Band theory and the supercluster observations of Tully, which conflict with the Big Band theory, are discussed. Various explanations for the existence of supercluster observations are proposed. The cosmic background explorer (COBE) is being utilized to detect energetic processes. The COBE contains a far IR absolute spectrometer, a differential microwave radiometer, and a diffuse IR background experiment. The hypothesis of the evolution of the universe of Hannes Alfven, which emphasizes the importance of electricity and magnetism, is presented and research illustrating the importance of electric currents and magnetic fields in space is examined.

British Library Electronic Table of Contents (United Kingdom)

Current multi-scale computational models of ventricular electromechanics describe the full process of cardiac contraction on both the micro- and macro- scales including: the depolarization of cardiac cells, the release of calcium from intracellular stores, tension generation by cardiac myofilaments, and mechanical contraction of the whole heart. Such models are used to reveal basic mechanisms of cardiac contraction as well as the mechanisms of cardiac dysfunction in disease conditions. In this paper, we present a methodology to construct finite element electromechanical models of ventricular contraction with anatomically accurate ventricular geometry based on magnetic resonance and diffusion tensor magnetic resonance imaging of the heart. The electromechanical model couples detailed repres...

International Nuclear Information System (INIS)

In the Wajima lung cancer screening program conducted under the auspices of Kanazawa University Hospital, Fuji Computed Radiography (FCR) was utilized in a new chest radiography trial. The results of the screening program are that the necessity of repeat examinations due to poor image quality are less common and the method enables detection of small pulmonary nodular shadows which are possibly candidates for surgery. Oblique chest X-ray with FCR is remarkably effective for the detection and the identification of small lesions. However, the disadvantage of slow processing and high cost must be fully satisfied if FCR is to become a new imaging modality for mass screening. (author).

International Nuclear Information System (INIS)

As part of the evolution of computer technology, Fuji Computed Radiography (FCR) has been developed as a new system for radiographical diagnosis. In this system, the X-ray energy is stored on the imaging plate and then converted into digital signals utilizing scanning laser-stimulated luminence. After proper image processing, it offers much more improved information for diagnosis than the conventional film system does. Since April, 1986, we have principally used FCR (System 101) for neurosurgical practice. In this article, we present our recent experience and evaluate its usefulness. (author).

International Nuclear Information System (INIS)

Results of ongoing research project at the McMaster Nuclear Reactor Facility on real-time neutron radiography for the visualization of interfacial geometry, movements and phase distributions in gas-liquid and gas-liquid-metal multi-phase flows are presented. Experiments were conducted with bubble column tubes with boiling liquid nitrogen, air-water and air-mercury mixtures. Discussions are also focused on air-water flowing within a tube containing a CANDU type 37 rod fuel bundle assembly positioned both horizontally and vertically. Computer processing using a digital image format to enhance the real-time images was used. Imaging techniques include frame averaging, background substraction, edge enhancement (spatial filtering), contrast enhancement and video densitometry. (orig.).

CERN Document Server

This paper proposes an adaptive morphological dilation image coding with context weights prediction. The new dilation method is not to use fixed models, but to decide whether a coefficient needs to be dilated or not according to the coefficient's predicted significance degree. It includes two key dilation technologies: 1) controlling dilation process with context weights to reduce the output of insignificant coefficients, and 2) using variable-length group test coding with context weights to adjust the coding order and cost as few bits as possible to present the events with large probability. Moreover, we also propose a novel context weight strategy to predict coefficient's significance degree more accurately, which serves for two dilation technologies. Experimental results show that our proposed method outperforms the state of the art image coding algorithms available today.

Energy Technology Data Exchange (ETDEWEB)

A thermal neutron imaging facility for real-time neutron radiography and computed tomography has been developed at the University of Texas reactor. The facility produced a good-quality radiographs and two-dimensional tomograms. Further developments have been recently accomplished. Further developments have been recently accomplished. A computer software has been developed to automate and expedite the data acquisition and reconstruction processes. Volume tomographic visualization using Interactive Data Language (IDL) software has been demonstrated and will be further developed. Volume tomography provides the additional flexibility of producing slices of the object using software and thus avoids redoing the measurements.

International Nuclear Information System (INIS)

To evaluate the usefulness of portable chest radiographs by Fuji computed radiography (FCR) in ICU, FCR radiographs of 56 patients who were admitted to General Intensive Care Unit of Keio University Hospital were compared with the conventional portable images. Because FCR could show two differently processed images in one film and allowed a wide range of image reproduction, visualization of the trachea, bone soft tissues and catheters by FCR was easier than that by the conventional radiography. Repeated radiographs by FCR had similar optical densities and limited exposure errors. Furthermore, radiation was reduced than that of the conventional radiography. In conclusion, FCR is thought to be a useful technique for portable chest radiography in ICU patients. (author).

Energy Technology Data Exchange (ETDEWEB)

A real-time neutron radiography imaging system has been installed at the Texas A and M University Nuclear Science Center. The system employs a scintillating screen viewed by a low-light TV camera with a front surface mirror placed at 45deg to the neutron beam. The key components of the system are the neutron camera and the image capture and processing unit. The neutron camera uses an NE 426 scintillating screen (ZnS), front surface mirror, remote focus and zoom lens, intensified relay optics (IRO) and monochrome CCD television camera. The image capture and processing unit consists of an IBM PC AT-compatible computer, arithmetic frame grabber, frame processor and high-resolution color monitor. The neutron camera is similar to others using a silicon intensified target (SIT) television camera to provide a TV image of the low-level light from a NE 426 screen. The ...

Energy Technology Data Exchange (ETDEWEB)

The field of neutron imaging has a broad scope of applications and has played a pivotal role in visualizing and quantifying hydrogenous masses in metallic matrices. The field continues to expand into new applications with the installation of new neutron imaging facilities. In this scope, a neutron imaging facility for computed tomography and real-time neutron radiography is currently being developed around 2.0 MW TRIGA MARK-II Reactor at Maamora Nuclear Research Centre in Morocco (CENM). The neutron imaging facility consists of a neutron collimator, a real-time neutron imaging system and imaging process systems. In order to reduce the gamma-ray content in the neutron beam, the reactor tangential channel was selected. For power of 250 kW, the corresponding thermal neutron flux measured at the inlet of the tangential channel is around 3.10{sup ...

Energy Technology Data Exchange (ETDEWEB)

The simulation of processes in engineering and the physical sciences has progressed rapidly over the last several years. With rapid developments in supercomputers, parallel processing, numerical algorithms and software, scientists and engineers are now positioned to quantitatively simulate systems requiring many billions of arithmetic operations. The need to understand and assimilate such massive amounts of data has been a driving force in the development of both hardware and software to create visual representations of the underling physical systems. In this paper, and the accompanying videotape, the evolution and development of the visualization process in scientific computing will be reviewed. Specific applications and associated imaging hardware and software technology illustrate both the computational needs and the evolving trends. 6 refs.

Energy Technology Data Exchange (ETDEWEB)

Uncertainty in computer vision can arise at various levels. It can occur in the low level in the raw sensor input, and extends all the way through intermediate and higher levels. Ideally, at any level where decisions are being made on the basis of previous processing steps, a computer vision system must have sufficient flexibility for representation of uncertainty in any of these levels. The input cue representation portion of a computer vision system should maintain the information content of the original input images, while at the same time allowing for uncertainty in the identification of attributes required by other parts of the system for decision making. Processes such as edge detection, segmentation, and shape matching yield results which could bias higher level decision making, unless some framework is defined for the representation of uncertainty in the context of fuzzy set theory where membership values associated ...

British Library Electronic Table of Contents (United Kingdom)

This study aimed to explore the impact of perceived service quality and self-concept on consumer attitude and purchase process using channel type (physical and Internet) as a segmentation variable. From the perspective of consumer behaviour, this study attempted to estimate a relational model and perform an empirical validation using female cosmetics and skincare products as an example. It was discovered that the influence of perceived service quality and self-concept on consumer attitude, purchase intention and behaviour, satisfaction, and loyalty varied with channel type. The analysis result revealed that physical stores presented higher levels of agreement with all research perspectives than Internet stores. However, only two relational paths have a higher influencing effect in physical...

British Library Electronic Table of Contents (United Kingdom)

Waste cooking oil can be recovered and processed into animal feed additives after purification. Unfortunately, the traditional purification processes are insufficient for the removal of the harmful compounds formed during frying, mainly about malondialdehyde and other 2-thiobarbituric acid reactive substances. In the present paper, firstly, a simple and reliable HPLC method was developed to measure the content of malondialdehyde in purified waste cooking oil. The detection limit and the standard recovery of the analysis method are 1.20x10-5gl-1 and 96.5-99.2%, respectively, which is accurate and valid enough for the detection of malondialdehyde in waste cooking oil. Furthermore, the removal of malondialdehyde and other 2-thiobarbituric acid reactive substances from waste cooking oil was in...

British Library Electronic Table of Contents (United Kingdom)

In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.

International Nuclear Information System (INIS)

Bone images obtained by single exposure dual energy subtraction with computed radiography, a new image processing method, were evaluated for the detectability of calcification in lung nodules in both phantom and clinical studies. In the phantom study, five simulated nodules containing known and uniformly distributed amounts of calcium hydroxide were placed in a human chest phantom and images were obtained the following five techniques: 1) conventional radiography (CXR), 2) low kV conventional radiography (Low), 3) Fuji computed radiography (FCR), 4) bone images with conventional singles exposure energy subtraction (ES) and 5) bone image with fine single exposure energy subtraction (FES). The detectability of calcification in the simulated nodules was evaluated by six radiologists using ROC analysis and two-way analysis of variance. In the clinical study, ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (inner diameter; 4.08mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3 M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the ...

Energy Technology Data Exchange (ETDEWEB)

This paper is concerned with the validation of the 3D deterministic neutral-particle transport theory code EVENT for shielding applications. The code is based on the finite element-spherical harmonics (FE-P{sub N}) method which has been extensively developed over the last decade. A general multi-group, anisotropic scattering formalism enables the code to address realistic steady state and time dependent, multi-dimensional coupled neutron/gamma radiation transport problems involving high scattering and deep penetration alike. The powerful geometrical flexibility and competitive computational effort makes the code an attractive tool for shielding applications. In recognition of this, EVENT is currently in the process of being adopted by the UK nuclear industry. The theory behind EVENT is described and its numerical implementation is outlined. Numerical results obtained by the code are compared with predictions of the Monte Carlo code MCBEND and ...

CERN Document Server

Sediment transport over wave-induced ripples is a very complex phenomenon where available models fail to provide accurate predictions. For coastal engineering applications, the 1-DV advection-diffusion equation could be used with an additional parameter {\\alpha} related to the process of vortex shedding above ripples (Absi, 2010). The aim of this study is to provide simple practical analytical tools. An analytical eddy viscosity profile was validated by DNS data of turbulent channel flows (Absi et al., 2011). In this study, we will show that: (1) the period-averaged eddy viscosity in oscillatory boundary layers could be described by this simple analytical formulation; (2) The shape of the vertical profile is validated by period-averaged eddy viscosity of baseline (BSL) k-{\\omega} model (Suntoyo and Tanaka, 2009) for sinusoidal and asymmetric waves; (3) The vertical eddy viscosity profile depends on the wave non-linearity ...

Energy Technology Data Exchange (ETDEWEB)

Essential to today's modern refineries and the gasoline production process are fluidized catalytic cracking units. By using a computational fluid dynamics (CFD) code developed at Argonne National Laboratory to simulate the riser, parametric and sensitivity studies were performed to determine the effect of catalyst inlet conditions on the riser hydrodynamics and on the product yields. Simulations were created on the basis of a general riser configuration and operating conditions. The results of this work are indications of riser operating conditions that will maximize specific product yields. The CFD code is a three-dimensional, multiphase, turbulent, reacting flow code with phenomenological models for particle-solid interactions, droplet evaporation, and chemical kinetics. The code has been validated against pressure, particle loading, and product yield measurements. After validation of the code, parametric studies ...

Energy Technology Data Exchange (ETDEWEB)

This article discussed a project formed to develop innovative seismic imaging technologies. The Kaleidoscope project aims to accelerate the processing of seismic sound waves by several orders of magnitude using advanced computer-based techniques to reveal oil and gas deposits buried deep in the earth in a manner that is both cost-effective and efficient. It is expected that the technology will be used in deep water applications with massive untapped reserves. The seismic technology will be used to locate hydrocarbons and oil reserves buried 20,000 feet beneath the seabed. It is estimated that the Gulf of Mexico contains 56 billion barrels of oil equivalent worth nearly $6 trillion. However, the reserves are difficult to locate due to the interbedded salt bodies in the subsurface. The project is simultaneously working on both hardware and software applications, and are currently writing the first petascale set of seismic ...

Energy Technology Data Exchange (ETDEWEB)

A new three-dimensional (3D) acoustic modelling method was developed using a first-order hyperbolic wave system which was solved with explicit finite dfferences. The numerical solution of the 3D wave system provides a useful method for simulating evolution of a pressure field corresponding to compressional type waves. Existing two-dimensional (2D) elastic modelling algorithms were modified and fine-tuned for computationally efficient and realistic wave propagation simulations in complex structures. An original formulation of the 3D reverse time migration method was developed which is very accurate, does not suffer from unwanted evenescent energy, can image dips beyond 90{degree}, and does not generate multiple energy. Two case studies were performed that involved steam stimulation projects in the Cold Lake deposit. Simulations were performed during different phases of the steam stimulation process to examine the relation between reservoir ...

International Nuclear Information System (INIS)

Purpose/Objective: At present, treatment verification between portal and reference images is performed based on manually-identified features by radiation oncologist, which is both time-consuming and potentially error-prone. There is a demand for the computerized verification procedure in clinical application. The purpose of this study is to develop a computerized portal verification scheme for pelvic treatment fields. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature matching between reference and portal images and quantitative evaluation of patient setup. Electronic portal images with a matrix size of 256 x 256 and 12 bit gray levels were acquired using a liquid matrix electronic portal imaging device. Simulation images were acquired by digitizing simulation films using a TV ...

International Nuclear Information System (INIS)

In the case of injuries of the ankle joint, an imaging technique is expected to reveal the state of the bones, ligaments, and articular cartilage. Irrespective of novel imaging techniques, a plain radiography will be made in order to obtain a first picture of the injury. Examples are given, showing that further orientation along the Lauge-Hansen classification scheme of this type of injury helps to completely ascertain the damage to the Articulatio talocruralis. Further examinations applying specific methods such as arthrography will detect possible, isolated syndesmosis ruptures; lesions of the ligaments can also be directly detected by CT or MRT. The articular cartilage and its lesions can be visualized by a combination of CT and arthrography, but are better shown by the completely non-invasive MRT. This latter method also gives insight into pathological processes with the bone. It allows to detect necrotic bone regions ...

International Nuclear Information System (INIS)

Neutron radiography (NR) is a useful non-destructive method for determination of hydrogen content in various building and technical materials. Monitoring of transport processes of moisture and hydrogenous liquids in porous building materials is enabled by fast, quasi-real-time NR methods based on novel imaging plate neutron detectors (IP-NDs). Hydrogen content in the samples is determined by quantitative analysis of measured profiles of neutron attenuation in the samples. Detailed description of quantitative NR method is presented by the authors in another accompanying contribution at this conference. Deterioration of building materials is originated by different processes that all require presence of water therefore it is essential to limit or prevent the transport of water through the porous material. In this presentation, results of a study of clay brick impregnation by silicone based hydrophobic agents will be ...

Energy Technology Data Exchange (ETDEWEB)

With respect to concept of resolution in seismic exploration using the reflection method, detailed considerations were given on processes of forming the resolution as a result of arranging observation points at vibration transmitting and receiving points. In the discussion, numerical experiments were carried out, in which the scattering stacking process is applied in a model having one scatterer existing in homogeneous media. The experiments investigated an imaging formation process of the scatterer when arrangement of the vibration transmitting and receiving points were changed from a coarse condition to a dense condition while the number of transmitting and receiving points is being increased. Resolution is created if waveforms having finite frequencies are used as input, and the imaging is performed by utilizing the limited number of vibration receiving and transmitting points. ...

International Nuclear Information System (INIS)

Secondary ion mass spectrometry (SIMS), secondary electron microscopy (SEM) and X-ray analysis have been applied to the measurement of U-bearing particles with the intent of gleaning information concerning their history and/or origin. The lead isotopic abundances are definitive indicators that U-bearing particles have come from an ore-body, even if they have undergone chemical processing. SEM images and X-ray analysis can add further information to the study that may allude to the extent of chemical processing. The presence of 'common' lead that does not exhibit a radiogenic signature is clear evidence of anthropogenic origin. (author)

UK PubMed Central (United Kingdom)

Multiple memory systems are involved in parallel processing of spatial information during navigation. A series of studies have distinguished between hippocampus-dependent ‘spatial’ navigation,...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Methods of solving Navier-Stokes equations for turbulent channel flow are given. These numerical solutions utilize either Neumann or Dirichlet boundary conditions. Computer codes were written and tested and are discussed. Digital image processing of flow visualization video sequences, taken simultaneously with vorticity probe measurements in a turbulent boundary layer, were carried out. 4 figs. (GHH)

International Nuclear Information System (INIS)

Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are unique to tomotherapy are highlighted. Many beam characteristics can be measured automatically by an included megavoltage computed tomography imaging system. This greatly improves data collection efficiency.

Science.gov (United States)

The MISR instrument aboard NASA's Terra satellite participated in the UAE-2 campaign, August-October 2004. This campaign represented a unique opportunity to study the complex aerosol situation in the Arabian Gulf region, in the context of a first-rate collection of aircraft and surface-based instruments, giving us the opportunity to do some groundbreaking satellite aerosol validation work. We aimed (1) to validate MISR aerosol retrieval results for dust and pollution particles over dark and light surfaces, and (2) to contribute regional maps of aerosol optical thickness (AOT) and particle micro-physical properties, giving spatial context to the field-instrument measurements, and moving toward a satellite-based regional aerosol climatology. The validation effort benefited from the combination of an instrumented aircraft and a regional network of surface-based sun photometers. We obtained high-quality sub-orbital data ...

International Nuclear Information System (INIS)

In this paper, we put forward a systematic method to analyze, control and evaluate the safety issues of medical robotics. We created a safety model that consists of three axes to analyze safety factors. Software and hardware are the two material axes. The third axis is the policy that controls all phases of design, production, testing and application of the robot system. The policy was defined as hazard identification and safety insurance control (HISIC) that includes seven principles: definitions and requirements, hazard identification, safety insurance control, safety critical limits, monitoring and control, verification and validation, system log and documentation. HISIC was implemented in the development of a robot for urological applications that was known as URObot. The URObot is a universal robot with different modules adaptable for 3D ultrasound image-guided interstitial laser coagulation, radiation seed implantation, laser resection, ...

Energy Technology Data Exchange (ETDEWEB)

Biodiesel made from vegetable oil is among the most desirable of renewable energy sources because it can be a substitute for diesel oil. However, biodiesel from soybean or corn can be confronted with a food crisis. Microalgae is a new biodiesel source which contains high oil lipids with a high growth rate, and which also offers value-added products from the residue, such as cosmetics, health functional food or pharmaceuticals. Microalgae are best cultivated in photo-bioreactors (PBRs) where light, nutrients, carbon dioxide and temperature can be controlled. Despite the current availability of PBRs, only a few can be practically used for mass production. Computational fluid dynamics (CFD) was used in this study to design an optimum bubble-column PBR for mass production of microalgae. Multi-phase models including bubble movement, meshes and time step independent tests were considered to develop the 3-dimensional CFD model. Particle Image Velocimetry (PIV) tests were ...

UK PubMed Central (United Kingdom)

The evaluation of biological markers is recognized as necessary to the future of toxicology, epidemiology, and quantitative risk assessment. For biological markers to become widely accepted, their validity...Full Text Available

Science.gov (United States)

... Standards Validation Group National Computer Systems Laboratory National Institute of Standards and Technology ... STANDARD. ... (See test Ci )i3A. ...

KoreaScience (Korea)

Full Text Available

Science.gov (United States)

The National Oceanic and Atmospheric Administration (NOAA), Department of Defense (DoD), and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation weather and environmental satellite system; the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS replaces the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA and the Defense Meteorological Satellite Program (DMSP) managed by the DoD. The NPOESS satellites carry a suite of sensors that collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The NPOESS design allows centralized mission management and delivers high quality environmental products to military, civil and scientific users. The ground data processing segment for NPOESS is the Interface Data Processing Segment (IDPS), developed by Raytheon Intelligence and ...

Energy Technology Data Exchange (ETDEWEB)

During the last years, boron dilution events with the potential of reactivity transients were an important issue of German PWR safety analyses. A coolant with a low-boron concentration could be collected in localized areas of the reactor coolant system, e.g., by separation of a borated reactor coolant into highly concentrated and diluted fractions (inherent dilution) which can occur during reflux-condenser heat transfer after a small break loss of coolant accident with a limited availability of the emergency core cooling systems. During the course of follower core assessments, TUV NORD SysTec appraises safety analyses of boron dilution events presented by the utilities. These analyses are based on the simulation of boron dilution and transport processes in conjunction with a number of dedicated experiments. The analyses demonstrate that boron dilution events cannot lead to recriticality of the core. Hence, the boron concentration at the core inlet has to be ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this experiment was to evaluate the diagnostic ability of a CCD-based digital system (CDX-2000HQ) in the detection of incipient dental caries. 93 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were radiographed using 4 imaging methods. Automatically processed No.2 Insight film (Eastman Kodak Co., U.S.A.) was used for conventional radiography, scanned images of conventional radiograms for indirect digital radiography were used. For the direct digital radiography, the CDX-2000HQ CCD system (Biomedisys Co. Korea) was used. The subtraction images were made from two direct digital images by Sunny program in the CDX-2000HQ system. Two radiologists and three endodontists examined the presence of lesions using a five-point confidence scale and compared the diagnostic ability by ROC (Receiver Operating Characteristic) analysis and one ...

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a three year DOE funded project titled ''A real-time coal content/ore grade (C{sub 2}OG) sensor''. The sensor, which is based on hyperspectral imaging technology, was designed to give a machine vision assay of ore or coal. Sensors were designed and built at Resonon, Inc., and then deployed at the Stillwater Mining Company core room in southcentral Montana for analyzing platinum/palladium ore and at the Montana Tech Spectroscopy Lab for analyzing coal and other materials. The Stillwater sensor imaged 91' of core and analyzed this data for surface sulfides which are considered to be pathfinder minerals for platinum/palladium at this mine. Our results indicate that the sensor could deliver a relative ore grade provided tool markings and iron oxidation were kept to a minimum. Coal, talc, and titanium sponge samples were also imaged and analyzed for content ...

Science.gov (United States)

Analysts working at the International Data Centre in support of treaty monitoring through the Comprehensive Nuclear-Test-Ban Treaty Organization spend a significant amount of time reviewing hypothesized seismic events produced by an automatic processing system. When reviewing these events to determine their legitimacy, analysts take a variety of approaches that rely heavily on training and past experience. One method used by analysts to gauge the validity of an event involves examining the set of stations involved in the detection of an event. In particular, leveraging past experience, an analyst can say that an event located in a certain part of the world is expected to be detected by Stations A, B, and C. Implicit in this statement is that such an event would usually not be detected by Stations X, Y, or Z. For some well understood parts of the world, the absence of one or more 'expected' stations - or the presence of one or ...

Energy Technology Data Exchange (ETDEWEB)

Commercial focused ion beam (FIB) systems are commonly used to image integrated circuits (ICS) after device processing, especially in failure analysis applications. FIB systems are also often employed to repair faults in metal lines for otherwise functioning ICS, and are being evaluated for applications in film deposition and nanofabrication. A problem that is often seen in FIB imaging and repair is that ICS can be damaged during the exposure process. This can result in degraded response or out-right circuit failure. Because FIB processes typically require the surface of an IC to be exposed to an intense beam of 30--50 keV Ga{sup +} ions, both charging and secondary radiation damage are potential concerns. In previous studies, both types of effects have been suggested as possible causes of device degradation, depending on the type of device examined and/or the bias conditions. ...

International Nuclear Information System (INIS)

The complex thermally stimulated luminescence (TSL) pattern of NaAlSi_3O_8 has been analyzed on transparent and opaque varieties of natural crystals and synthetic pure powder. The existence of seven additional peaks in the range 20 to 450 "0C following X-irradiation at room temperature (RT) is reported, also evaluated by the curve fitting method. The validity of the analysis is discussed in the light of detailed trap analysis of KAlSi_3O_8. An attempt has been made to probe the excistence of high temperature peaks beyond 450 "0C using UV stimulation at RT. All the TSL peaks analyzed follow a second-order kinetic process.

Energy Technology Data Exchange (ETDEWEB)

A new process for the removal of tar from biosyngas, OLGA (Oil and Gas Washer), is presented. This gas cleaning technology is based on physical principles and is designed to eliminate tar problems that relate to fouling and er pollution. The applied principles are confirmed by experimental validation. OLGA can be operated without suffering from harmful effects on important gasification characteristics as cold gas efficiency, gasifier simplicity, and feedstock flexibility. Some fundamental considerations in the development of OLGA are discussed. Amongst these is a different approach to the tar problem. This approach does not consider the total tar content as decisive in the evaluation of gas cleaning equipment. Instead, evaluation is focussed on whether tar properties as condensation behaviour and water solubility can still occur. A biosyngas free of tar should therefore be synonymous to a biosyngas that is free of tar related problems.

Science.gov (United States)

The aim of this paper is to illustrate the validity and efficiency of iterative methods for solving large linear systems arising from the finite element discretization of the equation governing conduction-controlled solidification processes. Starting from the basic enthalpy equation, two alternative formulations are obtained and fixed-grid finite element discretizations are developed. These discretizations yield a set of nonlinear equations that are linearized using the Newton-Raphson scheme. The linearized equations are used as a basis for evaluating different iterative methods of the conjugated gradient type. Symmetric scaling and incomplete factorization preconditioning of the linear equations are used to improve the convergence properties of the iterative methods. Vectorization and parallelization are also employed to make full use of the CRAY-2 supercomputer. The results indicate that the implementation of currently available iterative ...

International Nuclear Information System (INIS)

In the frame of the Primary Wall Module prototype manufacturing for ITER, a consistent R and D phase was conducted in order to identify the industrial allowable tolerances and manufacturing problems which would occur when joining pieces by HIPping process during the PW module manufacturing. The purpose of this development was to give as industrial as possible manufacturing routes for joining together large Stainless Steel or DS-Copper pieces with Stainless Steel tubes and for bonding Beryllium tiles onto a curved component surface. The study concerned surface preparations, allowable gaps and joint geometry, Beryllium tile geometry, Titanium interlayer thickness, etc. This R and D phase also allowed the development and validation of different ultrasonic inspection tools needed for plate-plate, tube-plate, edge to edge plate bonding.

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the proton spin.

Energy Technology Data Exchange (ETDEWEB)

Code coupling activities have so far focused on coupling the neutronics modules with the CFD module. An interface module for the CFD-ACE/DeCART coupling was established as an alternative to the original STAR-CD/DeCART interface. The interface module for DeCART/CFD-ACE was validated by single-pin model. The optimized CFD mesh was decided through the calculation of multi-pin model. It was important to consider turbulent mixing of subchannels for calculation of fuel temperature. For the parallel calculation, the optimized decompose process was necessary to reduce the calculation costs and setting of the iteration and convergence criterion for each code was important, too.

Energy Technology Data Exchange (ETDEWEB)

Results from this analysis show that the wood-value per hectare is rather the same whether we use the conventional harvester to harvest the pulpwood and timber only, or if we use a combination of a harvester and a chipping system to harvest the small trees for fuel. This is valid if the price of chips is on the same level as pulpwood. The incomes from the wood per hectare reduced with the harvesting costs differ between the two systems. We can see that the revenue per hectare is 34% higher when we harvest pulpwood only (9362 SEK compared to 6702 + 268 SEK). But if we only look at the revenue within the machine-system we can find it is more profitable to use the harvester for processing stems with larger diameter combined with a small scale system for harvesting fuel-wood from the small trees. 7 refs, 7 figs, 2 tabs

British Library Electronic Table of Contents (United Kingdom)

A new numerical technique called the convolution-based particle tracking (CBPT) method is developed to simulate resident or flux-averaged solute concentrations in groundwater models. The method is valid for steady-state flow and linear transport processes such as sorption with a linear sorption isotherm and first-order decay. The CBPT method uses particle tracking to take advantage of the ability of particle-based approaches to maintain sharp fronts for advection-dominated transport problems common in groundwater modeling and because of the flexibility of the random walk method to simulate a wide range of possible forms of the dispersion tensor. Furthermore, the algorithm for carrying out the convolution and superposition calculation from particle tracking results is very efficient. We sho...

Environmental Research Database

ObjectivesFirst comprehensive evaluation of the mechanical properties of an epoxy adhesive in different environments using a nano-indenter. ~%~~%~Use AFM/SEM and finite element modelling to generate knowledge of the precise mechanism of indentation in the epoxy adhesive. ~%~~%~Develop an improved data reduction algorithm for generating meaningful mechanical property data from indentation tests for adhesive materials.~%~ ~%~Validate the nano-indentation method of generating mechanical property data against [continued...]DescriptionThis project aims to address the problem of insufficient data on adhesive materials for effective modelling of joint behaviour in different environments. The methodology to be used is based on depth sensing indentation tests at different loads and rates and in different environments. Post-indentation deformation and recovery will be monitored by AFM and SEM and the indentation ...

CERN Document Server

The diffuse morphology and transient nature of coronal mass ejections (CMEs) make them difficult to identify and track using traditional image processing techniques. We apply multiscale methods to enhance the visibility of the faint CME front. This enables an ellipse characterisation to objectively study the changing morphology and kinematics of a sample of events imaged by the Large Angle Spectrometric Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO) and the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) onboard the Solar Terrestrial Relations Observatory (STEREO). The accuracy of these methods allows us to test the CMEs for non-constant acceleration and expansion. We exploit the multiscale nature of CMEs to extract structure with a multiscale decomposition, akin to a Canny edge detector. Spatio-temporal filtering highlights the CME front as it propagates in time. We apply an ...

Energy Technology Data Exchange (ETDEWEB)

For the application of dynamic neutron radiography to the two-phase flow research using HANARO, several experimental items to which the radiography technique is beneficial were identified through the review of the outputs from the related researches and the discussions with experts. Also, the investigation of the equipments including the beam port, camera and converter was made and a hardware and a software for image processing were equipped. It was confirmed that the calibration curve for the attenuation of neutron beam in fluid which is required for the two-phase flow experiment could be obtained by the computer code calculation. Based on the investigation results on the equipment and the results from the measurement of BNCT beam characteristics, a high speed camera and an image intensifier will be purchased. Then, the high speed dynamic neutron radiography facility for two-phase flow experiments will be fully equipped.

International Nuclear Information System (INIS)

For neutron radiography (NR), photographic techniques have been mainly used for many years. To observe a dynamic event and to test many samples, the real-time neutron radiography (i.e. neutron television - NTV) system has been introduced at the E-2 experimental tube of the Kyoto University Research Reactor (KUR). The NTV system has been practically applied to penetrating the side plates containing boron burnable poison to test MTR type reactor fuel, to investigation of moving objects and to neutron computed tomography (NCT). New approaches using some advanced neutron converters, a high sensitive and resolution TV camera and a high performance image processing system are being undertaken for standard indicators, visualization on air-water two-phase flow, NCT and so on. (author).

British Library Electronic Table of Contents (United Kingdom)

This article focuses on visual representations of subjective experiences of the process of recovery from addiction and the meanings that participants attribute to their visual work. The data are drawn from a study of six female participants. In this article, we discuss the results with reference to one participant, to allow for detailed consideration of the visual and the verbal material. This participant was selected because of the richness of her material, which provided an opportunity to carry out a detailed case study. Potential participants were informed in advance that they would be asked to draw during the interview. They were also asked to bring to the interview some artwork made during their engagement in creative activities at an earlier stage in their recovery. The data were ana...

Energy Technology Data Exchange (ETDEWEB)

The solubilities of plutonium and uranium have been determined for alkaline salt solutions having compositions which bound those which will be processed in the In-Tank Precipitation (ITP) process. Loadings of plutonium and uranium onto monosodium titanate (MST) have been determined at temperatures bounding those expected to occur during ITP and using a salt solution which was determined to have the maximum solubility for uranium and plutonium. Fissile loadings increase with decreasing amounts of MST in contact with the salt solutions saturated in plutonium and uranium. At MST concentrations bounding those which are planned for the ITP process, expressions for the maximum loadings (wt %) are determined to be 0.29 - 0.20x[MST] for plutonium and 1.8 - 0.29x[MST] for uranium, where [MST] is the concentration of MST in grams/liter. These expressions are valid over the range of MST concentrations from 0.05 to ...

Energy Technology Data Exchange (ETDEWEB)

Both the increased complexity of integrated circuits, resulting in six or more levels of integration, and the increasing use of flip-chip packaging have driven the development of integrated circuit (IC) failure analysis tools that can be applied to the backside of the chip. Among these new approaches are focused ion beam (FIB) tools and processes for performing chip edits/repairs from the die backside. This paper describes the use of backside FIB for a failure analysis application rather than for chip repair. Specifically, they used FIB technology to prepare an IC for inspection of voided metal interconnects (lines) and vias. Conventional FIB milling was combined with a super-enhanced gas assisted milling process that uses XeF{sub 2} for rapid removal of large volumes of bulk silicon. This combined approach allowed removal of the TiW underlayer from a large number of Ml lines simultaneously, enabling rapid localization and plan view ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Results of numerous experiments conducted over the past 15-years by using behavioural as well as brain imaging methods have shown that musical expertise influences brain anatomy, brain functions and behaviour. The musician- brain is thus considered as a very good model of brain plasticity. Moreover, many results have demonstrated that musical expertise not only impacts on music processing but also on several aspects of speech processing including lexical pitch, sentence intonation and the metric structure of words. Conversely, recent results indicated that linguistic expertise with tone or quantity languages such as Mandarin Chinese, Thai, Finnish and Japanese, influences the processing of harmonic tones and musical intervals. We discuss possible interpretations of these findings ...

Science.gov (United States)

Seasonal Allergic Rhinitis

Norwegian Open Research Archives (NORA)

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International Nuclear Information System (INIS)

Intervertebral spacers for anterior spine fusion are made of different materials, such as titanium and cobalt chromium alloys and carbon fiber-reinforced polymers. Implant-related susceptibility artifacts can decrease the quality of MRI scans. The aim of this cadaveric study was to demonstrate the extent that implant-related MRI artifacting affects the postfusion differentiation of determined regions of interest (ROIs). In six cadaveric porcine spines, we evaluated the postimplantation MRI scans of a titanium, cobalt-chromium and carbon spacer that differed in shape and surface qualities. A spacer made of human cortical bone was used as a control. A defined evaluation unit was divided into ROIs to characterize the spinal canal as well as the intervertebral disc space. Considering 15 different MRI sequences read independently by an interobserver-validated team of specialists the artifact-affected image quality of the median MRI slice was rated ...

KoreaScience (Korea)

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Science.gov (United States)

We have investigated the nanotexture and crystallographic orientation of aragonite in a coral skeleton using synchrotron-based scanning transmission X-ray microscopy (STXM) and transmission electron microscopy (TEM). Polarization-dependent STXM imaging at 40-nm spatial resolution was used to obtain an orientation map of the c-axis of aragonite on a focused ion beam milled ultrathin section of a Porites coral. This imaging showed that one of the basic units of coral skeletons, referred to as the center of calcification (COC), consists of a cluster of 100-nm aragonite globules crystallographically aligned over several micrometers with a fan-like distribution and with the properties of single crystals at the mesoscale. The remainder of the skeleton consists of aragonite single-crystal fibers in crystallographic continuity with the nanoglobules comprising the COC. Our observation provides information on the nm-scale processes ...

CERN Document Server

The hurried development of multimedia and internet allows for wide distribution of digital media data. It becomes much easier to edit, modify and duplicate digital information. In additional, digital document is also easy to copy and distribute, therefore it may face many threats. It became necessary to find an appropriate protection due to the significance, accuracy and sensitivity of the information. Furthermore, there is no formal method to be followed to discover a hidden data. In this paper, a new information hiding framework is presented.The proposed framework aim is implementation of framework computation between advance encryption standard (AES) and distortion technique (DT) which embeds information in image page within executable file (EXE file) to find a secure solution to cover file without change the size of cover file. The framework includes two main functions; first is the hiding of the information in the image page of EXE file, ...

International Nuclear Information System (INIS)

Three dimensional data of brain from the formalin-fixed fetuses were collected without isolation, by the 4.7 tesla super high magnetic field MRI and the developmental process of the cerebral parenchyma was studied by 3D images. Subjects were 13 fetal brain and MRI was performed using 3D-steady-state free precession sequence. The isolated brain is very soft and fragile and is deformed by its weight at the imaging. However 3D-MRI can be obtained without isolation, and the deformation is remarkably small. The subependymal germinal matrix layer did not be observed in 7 weeks-old fetus, appeared at 9 weeks-old and increased gradually. Then it rapidly reduced from 28 weeks-old. The volume calculated, from 3D-MRI, increased rapidly from 9 weeks-old to 23 weeks-old, and reached the maximum (2.346 mm"3) at 23 weeks-old. The relation between fetal ages and volume of cerebral ventricle also showed similar pattern. This method will be ...

International Nuclear Information System (INIS)

Diagnostic capability of Fuji Computed Radiography (FCR) of the chest was compared to the conventional radiography (CoR) using regular film-screen system. FCR utilizers imaging plates of scanning laser stimulated luminescence. Visibility of 14 structures of the chest radiography was evaluated by 3 radiologists in 100 pairs of FCR and CoR which were taken at the same time with the same exposure factors. FCR was superior to CoR especially in observation of the mediastinum and areas behind the heart and diaphragm. The minor fissure was better seen on CoR. Superiority of FCR to CoR was thought to be mainly due to the processed image of FCR, and the so-called normal image of FCR had little diagnostic advantage. Simulated abnormal densities: nodular, alveolar, and interstitial densities with a chest phantom, were made, and detectability of alteration of these densities on FCR and CoR was evaluated by 19 ...

Energy Technology Data Exchange (ETDEWEB)

Radiographic images generated by the real-time neutron radiography system (RTNR) are analyzed by customized image processing software of the determination of instantaneous void fraction distribution. The cross-sectional averaged axial void fraction profiles and the two-dimensional void fraction profiles are determined simultaneously for each image. Various flow regimes are generated to determine if the RTNR system can accurately predict the void distribution in the radial, axial, and temporal coordinates. The results show the RTNR system correctly determines the void fraction distribution for each flow regime; however, accuracy decreases with decreasing void fraction. For net water thicknesses > 1.0 cm, the accuracy decreases with increasing water thickness due to the extreme sensitivity of thermal neutron interactions with light water. Heavy water is a more suitable fluid than light water for void ...

Science.gov (United States)

A first-principles task-based approach to the design of medical ultrasonic imaging systems for breast lesion discrimination is described. This study explores a new approximation to the ideal Bayesian observer strategy that allows for object heterogeneity. The new method, called iterative Wiener filtering, is implemented using echo data simulations and a phantom study. We studied five lesion features closely associated with visual discrimination for clinical diagnosis. A series of human observer measurements for the same image data allowed us to quantitatively compare alternative beamforming strategies through measurements of visual discrimination efficiency. Employing the Smith-Wagner model observer, we were able to breakdown efficiency estimates and identify the processing stage at which performance losses occur. The methods were implemented using a commercial scanner and a cyst phantom to explore development of spatial ...

UK PubMed Central (United Kingdom)

Image enhancement is of great importance in medical imaging where image resolution remains a crucial point in many image analysis algorithms. In this paper, we investigate brain hallucination...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. After subdividing subsurface into triangular element we shoot off the ray into subsurface by the Snell`s law. And then after taking the ray path which is similar to proper assumption we can calculate ...

Energy Technology Data Exchange (ETDEWEB)

Since April, 1985, we have, in co-operation with the Fuji Film Co., Ltd., used Fuji Computed Radiography (FCR) in the diagnosis of spinal disorders. FCR is a new computed radiographic system which uses an energy-storage phosphorus panel called an ''Imaging Plate'' as an image sensor. The ''Imaging Plate'' can be used to obtain radiographs in exactly the same way as the screen-film combination used in conventional radiography; X-rays are exposed on the ''Imaging Plate'' instead of X-ray film in the conventional fashion, and then the ''Imaging Plate'' is calculated. The processed digital data from the scans is transformed into a picture by means of digital-to-analogue conversion. The pictures are always clear and ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to assess experimentally and clinically the usefulness of Fuji Computed Radiography (FCR) in angiographic examinations. FCR had a spatial resolution with much lower X-ray exposure doses, although the resolution of FCR was generally inferior to conventional films. When a contrast medium of 1% iodine concentration was used, FCR pinpointed a mass 1.5 mm in diameter; and conventional film could detect a mass 2.2 mm in diameter. The contrast of iodine in FCR examinations was stable. A high sensitivity of imaging plate allowed a wide range of visualization. In 148 selective angiographic examinatinons for 138 patients, FCR-subtraction images were superior to conventional film angiography for contrast resolution; it had a high sensitivity in detecting areas, such as the mediastimun and left lobe of the liver, and tumor stains in capillary phase. The capability of FCR arteriogram was as good as film arteriogram even with a ...

International Nuclear Information System (INIS)

Fuji Computed Radiography (FCR) utilizes imaging plates of scanning lazer stimulated luminescence. FCR can be used for intravenous digital subtraction angiography (IVDSA) and for intraarterial studies because of tis high contrast and spatial resolution. Pixel size of the imaging plates for angiography is 0.2 mm. Experimentally, it could demonstrate a vessel 1 mm in diameter with a contrast of 0.1, when opacified with a contrast medium of 3 % iodine concentration, and could image a vessel 3 mm in diameter with contrast of 0.1, when opacified with 1 % contrast medium. A 20 % stenosed portion of a vessel 3 mm in diameter was identified when opacified with 3 % contrast medium, and a 20 % stenosed portion of a vessel 2 mm in diameter was identified when opacified with 10 % contrast medium. In 105 IVDSA examinations of 75 patients, FCR was superior to Digital Fluorography (DF) in spatial resolution, size of examination field, ...

International Nuclear Information System (INIS)

Quantitative evaluation of CRT and CR observations in indentification of malignancy using phantom and clinical data. A breast phantom and a total of 40 patients were imaged by Fuji computed radiography (FCR). The images were interpreted twice by six radiologists both on CR film (2510 x 2000 pixels x 10 bits, 0.1 mm spatial resolution) and on a CRT monitor (1568 x 1152 pixels x 10 bits, 0.1 mm pixel size with double expansion) with image processing parameters of a toutine (RN 1.0, RE 0.2), for a calcification (RN 9.0, RE 4.0) and for a mass (RN 7.0, RE 2.0). The forty clinical cases included breast diseases with calcifications, masses, and normal breasts. Two-tailed t-test was performed to analyze interpretation of simulated microcalcifications and masses in the phantom. The receiver operating characteristic (ROC) analysis was performed to evaluate clinical cases. In all interpretation studies using both ...

Science.gov (United States)

High salinity is one of the main factors limiting cotton growth and productivity. The genes that regulate salt stress in TM-1 upland cotton were monitored using microarray and real-time PCR (RT-PCR) with samples taken from roots. Microarray analysis showed that 1503 probe sets were up-regulated and 1490 probe sets were down-regulated in plants exposed for 3h to 100mM NaCl, and RT-PCR analysis validated 42 relevant/related genes. The distribution of enriched gene ontology terms showed such important processes as the response to water stress and pathways of hormone metabolism and signal transduction were induced by the NaCl treatment. Some key regulatory gene families involved in abiotic and biotic sources of stress such as WRKY, ERF, and JAZ were differentially expressed. Our transcriptome analysis might provide some useful insights into salt-mediated signal transduction pathways in cotton and offer a number of candidate genes as potential ...

Energy Technology Data Exchange (ETDEWEB)

A numerical investigation of a humidification dehumidification desalination (HDD) process using solar energy is presented. The HDD system consists mainly of a concentrating solar water heating collector, flat plate solar air heating collector, humidifying tower and dehumidifying exchanger. Two separate circulating loops constitute the HDD system, the first for heating the feed water and the second for heating air. A mathematical model is developed, simulating the HDD system, to study the influence of the different system configurations, weather and operating conditions on the system productivity. The model validity is examined by comparing the theoretical and experimental results of the same authors. It is found that the results of the developed mathematical model are in good agreement with the experimental results and other published works. The results show also that the productivity of the unit is strongly influenced by the air flow rate, ...

British Library Electronic Table of Contents (United Kingdom)

Electrodeposition of tertiary alumina/yttria/carbon nanotube (Al2O3/Y2O3/CNT) nanocomposite by using pulsed current has been studied in this investigation. Coating process has been performed on nickel sulphate bath and nanostructure of obtained compound layer is examined with high precision figure analysis of SEM nanographs. The effects of process variables, i.e., Y2O3 concentration, treatment time, frequency and duty cycle, have been experimentally studied. Statistical methods are used to achieve the minimum of corrosion rate and average size of nanoparticles. Finally the contribution percentage of different effective factors is revealed and confirmation run shows the validity of obtained results. Also it has been revealed that by changing the size of nanoparticles, corrosion properties o...

CERN Document Server

It has by now been established that standard QCD factorization using transverse momentum dependent parton distribution functions fails in hadro-production of nearly back-to-back hadrons with high transverse momentum. The essential problem is that gauge invariant transverse momentum dependent parton distribution functions cannot be defined with process-independent Wilson line operators, thus implying a breakdown of universality. This has led naturally to proposals that a correct approach is to instead use a type of "generalized" transverse momentum dependent factorization in which the basic factorized structure is assumed to remain valid, but with transverse momentum dependent parton distribution functions that contain non-standard, process dependent Wilson line structures. In other words, to recover a factorization formula, it has become common to assume that it is sufficient to simply modify the Wilson lines in the parton ...

Energy Technology Data Exchange (ETDEWEB)

Verification and validation issues have been perceived as important factors in the large scale deployment of knowledge-based digital systems for plant transient diagnostics and management. Research and development (R&D) is being performed on the IGENPRO package to resolve knowledge base issues. The IGENPRO approach is to structure the knowledge bases on generic thermal-hydraulic (T-H) first principles and not use the conventional event-basis structure. This allows for generic comprehensive knowledge, relatively small knowledge bases and above all the possibility of T-H system/plant independence. To demonstrate concept feasibility the knowledge structure has been implemented in the diagnostic module PRODIAG. Promising laboratory testing results have been obtained using data from the full scope Braidwood PWR operator training simulator. This knowledge structure is now being implemented in the transient management module PROMANA to treat unanticipated events and ...

Energy Technology Data Exchange (ETDEWEB)

A new small size gamma irradiator is being set up at Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Brazil, with a revolutionary design. The developed technology for this facility consists of continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m{sup 2} of floor area, the irradiator design is product overlap sources and the maximum capacity of Cobalt-60 wet sources is 37 PBq (1 MCi). The irradiator is being installed in a Governmental Institution and it will be used as a demonstration facility for manufacturers, who need an economic and logistic in-house irradiation system alternative. Also, it will be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the ...

Energy Technology Data Exchange (ETDEWEB)

VSP data are usually recorded in common-shot gather and contain less informations. It is difficult, therefore, to obtain good migration result by using conventional migration methods. Both inner interface reflections and interformational multiples can be removed by reverse-time migration with the use of two-way nonreflection wave equation: besides, boundary reflection in VSP can be eliminated using Clayton's absorption boundary condition. It is proved that reverse-time migration is able to improve migration quality. The imaging condition is still obtained by generalizing Claerbout's imaging principle and solving eikonal equation. This is a very practical wave equation migration method. This method is applicable to prestack VSP data, conventional multiple-offset shot gather and the simultaneous migration of VSP data and surface seismic data. Besides, it is adaptable to various velocity variations. Before applying the method to ...

Energy Technology Data Exchange (ETDEWEB)

Fabrication of diffused titanium optical guides on a LiNbO/sub 3/ crystal substrate requires precise quality assurance. Light couplers in particular must be positioned within micron specifications. This requirement is the reason that the width of lines detected during microscopic inspection of the crystal is such an important parameter for quality evaluation. To assist in the inspection of these optical guides, a line width estimation program has been developed for an IBM PC based microscope inspection system. A digital image processing approach is used to develop an algorithm which can be tailored by the user for specific signal and noise characteristics. Default filter parameters, which can be updated and saved interactively by the user, are stored in a file on disk. The final program can be executed stand-alone or through a commercially available, menu-driven, image processing software package. ...