WorldWideScience

Sample records for pacs photometric imaging

  1. PACS for imaging centers.

    Science.gov (United States)

    Farnsworth, T J

    2003-01-01

    PACS can be a difficult and confusing decision for any radiology provider, but it can be an even more dynamic question for an outpatient imaging center. Every center represents a unique situation and requires a specialized solution. Typically, most of what is said and discussed about PACS concentrates on solutions and requirements for hospital radiology facilities. Administrators of imaging centers have different problems from hospital administrators, and they need different answers. For imaging centers, the financial justification for PACS may be less immediate than for hospitals. The first thing that must be understood is that no PAC system can make a typical imaging center completely filmless, at least not for quite a while. A hospital has the ability to dictate to its internal referring physicians how a radiological study is delivered, whereas in an imaging center environment, the roles are very much reversed. Once the justification are made for the financial viability of PACS in an imaging center, the next question is how to finance the acquisition of PACS. The decision will depend on how you cost justify your PACS, as well as the shape of your business model, and it will come to a decision between capital purchase or contracting with an application service provider, or ASP. Historically, in the hospital-dominated marketplace, PAC systems have been treated as capital acquisitions. However, for most imaging center, owning the system is more of a problem than a benefit. ASPs increasingly represent a successful alternative for imaging centers. One of the biggest things to consider with PACS is how to store all of those images. There are typically two options, on-site and off-site, with a new "hybrid" option surfacing more recently. Each option has benefits for the user, but the benefits of off-site storage are increasing as the technology advances. Some of the benefits are data security and access. Other issues to address are HIPAA compliance, standardized

  2. Diagnostic image workstations ofr PACS

    International Nuclear Information System (INIS)

    Meyer-Ebrecht, D.; Fasel, B.; Dahm, M.; Kaupp, A.; Schilling, R.

    1990-01-01

    Image workstations will be the 'window' to the complex infrastructure of PACS with its intertwined image modalities (image sources, image data bases and image processing devices) and data processing modalities (patient data bases, departmental and hospital information systems). They will serve for user-to-system dialogues, image display and local processing of data as well as images. Their hardware and software structures have to be optimized towards an efficient throughput and processing of image data. (author). 10 refs

  3. PACS strategy for imaging centers.

    Science.gov (United States)

    Bedel, Victoria; Zdanowicz, Mark

    2004-01-01

    Picture archiving and communications systems (PACS) have been available in imaging centers for many years, but they often were less functional, were not well integrated into patient information systems, and lacked the network backbone to implement a system. As modalities are replaced and technology improves, the ability and time for an imaging center to acquire, integrate, and utilize PACS has arrived. However, each imaging center must determine why it should invest in PACS. A business plan is the fundamental need. Each imaging center must understand its target market, growth rate, and staffing plans. Additional considerations lie in current and future modality availability, the need for offsite delivery of images and reports, and the potential need for remote transmission of images. These issues must be identified and prioritized. A multidisciplinary team is essential. The most successful PACS implementation begins with complete involvement from all levels. The team should be comprised of people with complementary skills who are committed to a common purpose, set of performance goals, and approach for which they hold themselves mutually accountable. The team must jointly decide on the project's objectives. These objectives fall under 4 categories: clinical, service, financial, and performance. PACS must be considered a tool to help accomplish each objective. The imaging center must determine its top priorities, then translate them into a technology "wish list." The center can then list those pieces of technology that are most important and prioritize them. There are even more considerations for connecting multiple imaging centers. The team must create a comprehensive request for proposal (RFP) and determine the vendors that will receive the document. Once the RFP responses have been received and the vendor has been selected, an effective training plan must be executed. Training plans should be competency-based, ensuring comfort and competency among all staff. Upon

  4. Medical imaging, PACS, and imaging informatics: retrospective.

    Science.gov (United States)

    Huang, H K

    2014-01-01

    Historical reviews of PACS (picture archiving and communication system) and imaging informatics development from different points of view have been published in the past (Huang in Euro J Radiol 78:163-176, 2011; Lemke in Euro J Radiol 78:177-183, 2011; Inamura and Jong in Euro J Radiol 78:184-189, 2011). This retrospective attempts to look at the topic from a different angle by identifying certain basic medical imaging inventions in the 1960s and 1970s which had conceptually defined basic components of PACS guiding its course of development in the 1980s and 1990s, as well as subsequent imaging informatics research in the 2000s. In medical imaging, the emphasis was on the innovations at Georgetown University in Washington, DC, in the 1960s and 1970s. During the 1980s and 1990s, research and training support from US government agencies and public and private medical imaging manufacturers became available for training of young talents in biomedical physics and for developing the key components required for PACS development. In the 2000s, computer hardware and software as well as communication networks advanced by leaps and bounds, opening the door for medical imaging informatics to flourish. Because many key components required for the PACS operation were developed by the UCLA PACS Team and its collaborative partners in the 1980s, this presentation is centered on that aspect. During this period, substantial collaborative research efforts by many individual teams in the US and in Japan were highlighted. Credits are due particularly to the Pattern Recognition Laboratory at Georgetown University, and the computed radiography (CR) development at the Fuji Electric Corp. in collaboration with Stanford University in the 1970s; the Image Processing Laboratory at UCLA in the 1980s-1990s; as well as the early PACS development at the Hokkaido University, Sapporo, Japan, in the late 1970s, and film scanner and digital radiography developed by Konishiroku Photo Ind. Co. Ltd

  5. Enterprise imaging and multi-departmental PACS

    International Nuclear Information System (INIS)

    Bergh, Bjoern

    2006-01-01

    The aim of this review is to present the status of digital image acquisition and archiving outside of radiology and to describe the technical concepts and possibilities of how a ''radiology'' Picture Archiving and Communication System (PACS) can become a multi-departmental (MD-)PACS. First the principles of system integration technology are explained and illustrated by the description of a typical radiology system integration. Then four types of modality integration approaches are defined: the direct modality integration (Type-I), the integration via DICOM acquisition software (Type-II) the integration via specialised systems either with (Type-III) or without PACS connection (Type-IV). The last section is dedicated to the presentation of the PACS requirements of selected interdisciplinary modality types [Endoscopy, Ultrasound and Electrocardiography (ECG)] and clinical disciplines (Pathology, Dermatology, Ophthalmology and Cardiology), which are then compared with the technical possibilities of a MD-PACS. (orig.)

  6. [PACS-based endoscope image acquisition workstation].

    Science.gov (United States)

    Liu, J B; Zhuang, T G

    2001-01-01

    A practical PACS-based Endoscope Image Acquisition Workstation is here introduced. By a Multimedia Video Card, the endoscope video is digitized and captured dynamically or statically into computer. This workstation realizes a variety of functions such as the endoscope video's acquisition and display, as well as the editing, processing, managing, storage, printing, communication of related information. Together with other medical image workstation, it can make up the image sources of PACS for hospitals. In addition, it can also act as an independent endoscopy diagnostic system.

  7. PACS module image communication at UCLA

    International Nuclear Information System (INIS)

    Stewart, B.K.; Taira, R.K.; Cho, P.S.; Mankovich, N.J.

    1987-01-01

    The advent of the ACR-NEMA digital and communication standard for PACS implementation between imaging, storage and display devices may simplify the networking problems inherent to PACS in the future. However, since the ACR-NEMA interface has not been implemented in manufactured products, the components of a PACS at the present time use various network interface designs, requiring substantial effort in the area of hardware and software integration. Many communication systems are used for the PACS implementation in Pediatric Radiology at UCLA, including baseband, broadband, as well as various parallel-line interface protocols, e.g. GP-IB. A VAX 11/750 minicomputer serves as the host computer for the UCLA Pediatric Radiology PACS system. Communication between the many peripherals take place through the host computer, which acts as the central node. Several communication links have been established, primarily: host computer to other local computers, image processors, various peripherals (digitizers, storage media, etc.) and, of course, to the 512, 1024 and 2048 viewing stations

  8. Authenticity techniques for PACS images and records

    Science.gov (United States)

    Wong, Stephen T. C.; Abundo, Marco; Huang, H. K.

    1995-05-01

    Along with the digital radiology environment supported by picture archiving and communication systems (PACS) comes a new problem: How to establish trust in multimedia medical data that exist only in the easily altered memory of a computer. Trust is characterized in terms of integrity and privacy of digital data. Two major self-enforcing techniques can be used to assure the authenticity of electronic images and text -- key-based cryptography and digital time stamping. Key-based cryptography associates the content of an image with the originator using one or two distinct keys and prevents alteration of the document by anyone other than the originator. A digital time stamping algorithm generates a characteristic `digital fingerprint' for the original document using a mathematical hash function, and checks that it has not been modified. This paper discusses these cryptographic algorithms and their appropriateness for a PACS environment. It also presents experimental results of cryptographic algorithms on several imaging modalities.

  9. Reengineering the picture archiving and communication system (PACS) process for digital imaging networks PACS.

    Science.gov (United States)

    Horton, M C; Lewis, T E; Kinsey, T V

    1999-05-01

    Prior to June 1997, military picture archiving and communications systems (PACS) were planned, procured, and installed with key decisions on the system, equipment, and even funding sources made through a research and development office called Medical Diagnostic Imaging Systems (MDIS). Beginning in June 1997, the Joint Imaging Technology Project Office (JITPO) initiated a collaborative and consultative process for planning and implementing PACS into military treatment facilities through a new Department of Defense (DoD) contract vehicle called digital imaging networks (DIN)-PACS. The JITPO reengineered this process incorporating multiple organizations and politics. The reengineered PACS process administered through the JITPO transformed the decision process and accountability from a single office to a consultative method that increased end-user knowledge, responsibility, and ownership in PACS. The JITPO continues to provide information and services that assist multiple groups and users in rendering PACS planning and implementation decisions. Local site project managers are involved from the outset and this end-user collaboration has made the sometimes difficult transition to PACS an easier and more acceptable process for all involved. Corporately, this process saved DoD sites millions by having PACS plans developed within the government and proposed to vendors second, and then having vendors respond specifically to those plans. The integrity and efficiency of the process have reduced the opportunity for implementing nonstandard systems while sharing resources and reducing wasted government dollars. This presentation will describe the chronology of changes, encountered obstacles, and lessons learned within the reengineering of the PACS process for DIN-PACS.

  10. Reengineering the picture archiving and communication system (PACS) process for digital imaging networks PACS

    OpenAIRE

    Horton, Maria C.; Lewis, Thomas E.; Kinsey, Thomas V.

    1999-01-01

    Prior to June 1997, military picture archiving and communications systems (PACS) were planned, procured, and installed with key decisions on the system, equipment, and even funding sources made through a research and development office called Medical Diagnostic Imaging Systems (MDIS). Beginning in June 1997, the Joint Imaging Technology Project Office (JITPO) initiated a collaborative and consultative process for planning and implementing PACS into military treatment facilities through a new ...

  11. The management and realizing of image data flow in PACS

    International Nuclear Information System (INIS)

    Tao Yonghao; Miao Jingtao

    2002-01-01

    Objective: To explore the management model and realizing of PACS image data-flow. Methods: Based on the implementing environment and management model of PACS image data-flow after full digital reengineering for radiology department in Shanghai First Hospital was completed, analysis on image data flow types, procedure, and achieving pattern were conducted. Results: Two kinds of image data-flow management were set up for the PACS of Shanghai First Hospital, which included image archiving procedure and image forward procedure. The former was implemented with central management model while the latter was achieved with a program that functionally acted as workflow management running on the central server. Conclusion: The image data-flow management pattern, as a key factor for PACS, has to be designed and implemented functionally and effectively depending on the performance environment, the tasks and requirements specified to particular user

  12. Integration Of An MR Image Network Into A Clinical PACS

    Science.gov (United States)

    Ratib, Osman M.; Mankovich, Nicholas J.; Taira, Ricky K.; Cho, Paul S.; Huang, H. K.

    1988-06-01

    A direct link between a clinical pediatric PACS module and a FONAR MRI image network was implemented. The original MR network combines together the MR scanner, a remote viewing station and a central archiving station. The pediatric PACS directly connects to the archiving unit through an Ethernet TCP-IP network adhering to FONAR's protocol. The PACS communication software developed supports the transfer of patient studies and the patient information directly from the MR archive database to the pediatric PACS. In the first phase of our project we developed a package to transfer data between a VAX-111750 and the IBM PC I AT-based MR archive database through the Ethernet network. This system served as a model for PACS-to-modality network communication. Once testing was complete on this research network, the software and network hardware was moved to the clinical pediatric VAX for full PACS integration. In parallel to the direct transmission of digital images to the Pediatric PACS, a broadband communication system in video format was developed for real-time broadcasting of images originating from the MR console to 8 remote viewing stations distributed in the radiology department. These analog viewing stations allow the radiologists to directly monitor patient positioning and to select the scan levels during a patient examination from remote locations in the radiology department. This paper reports (1) the technical details of this implementation, (2) the merits of this network development scheme, and (3) the performance statistics of the network-to-PACS interface.

  13. [Economic and organizational evaluation of an imaging network (PACS)].

    Science.gov (United States)

    Charvet-Protat, S; Thoral, F

    1998-12-01

    Over the last twenty years, imaging modalities featuring new image production methods (ultrasound, nuclear magnetic resonance, etc.) have appeared on the market. Nevertheless, conventional radiology still accounts for 70% of the image examinations carried out in most western countries, including France. The conventional radiological image is in the process of evolving from analog to digital form. Digitalization of radiology means that image acquisition, archiving and distribution functions that were previously carried out by hand can now be automated using a Picture Archiving and Communication System. Decision-makers are having to decide whether or not to promote the development of PACS which, while they considerably modernize the way in which images are managed, also require heavy capital outlays. A critical appraisal of the literature allowed us to evaluate the relative cost and the efficiency of these image networks in comparison with film-based archiving and communication systems. It is clear from the economic evaluation that a PACS strategy involves greater costs than a film system. While PACS systems do generate savings on film and on storage space and obviate the need for certain staff, these savings do not offset the extra equipment and maintenance costs. This situation is likely to persist for some years yet, even when future price reductions are taken into account. The objective of this new radiological information management method is to improve organizational efficiency and hospital productivity. However, the economic evaluations that have been published to date are cost studies which do not take the efficiency criterion into account. A number of potential organizational benefits such as the fact that medical decisions can be made more quickly or that the average length of hospital stays can be reduced, are often claimed for PACS. However, for methodological reasons, these results cannot be generalised to cover all PACS. It is difficult to compare PACS

  14. Java-based cryptosystem for PACS and tele-imaging

    Science.gov (United States)

    Tjandra, Donny; Wong, Stephen T. C.; Yu, Yuan-Pin

    1998-07-01

    Traditional PACS systems are based on two-tier client server architectures, and require the use of costly, high-end client workstations for image viewing. Consequently, PACS systems using the two-tier architecture do not scale well as data increases in size and complexity. Furthermore, use of dedicated viewing workstations incurs costs in deployment and maintenance. To address these issues, the use of digital library technologies, such as the World Wide Web, Java, and CORBA, is being explored to distribute PACS data to serve a broader range of healthcare providers in an economic and efficient manner. Integration of PACS systems with digital library technologies allows access to medical information through open networks such as the Internet. However, use of open networks to transmit medical data introduces problems with maintaining privacy and integrity of patient information. Cryptography and digital timestamping is used to protect sensitive information from unauthorized access or tampering. A major concern when using cryptography and digital timestamping is the performance degradation associated with the mathematical calculations needed to encrypt/decrypt an image dataset, or to calculate the hash value of an image. The performance issue is compounded by the extra layer associated with the CORBA middleware, and the use of programming languages interpreted at the client side, such as Java. This paper study the extent to which Java-based cryptography and digital timestamping affects performance in a PACS system integrated with digital library technologies.

  15. Herschel-PACS photometry of faint stars for sensitivity performance assessment and establishment of faint FIR primary photometric standards

    Science.gov (United States)

    Klaas, U.; Balog, Z.; Nielbock, M.; Müller, T. G.; Linz, H.; Kiss, Cs.

    2018-05-01

    Aims: Our aims are to determine flux densities and their photometric accuracy for a set of seventeen stars that range in flux from intermediately bright (≲2.5 Jy) to faint (≳5 mJy) in the far-infrared (FIR). We also aim to derive signal-to-noise dependence with flux and time, and compare the results with predictions from the Herschel exposure-time calculation tool. Methods: We obtain aperture photometry from Herschel-PACS high-pass-filtered scan maps and chop/nod observations of the faint stars. The issues of detection limits and sky confusion noise are addressed by comparison of the field-of-view at different wavelengths, by multi-aperture photometry, by special processing of the maps to preserve extended emission, and with the help of large-scale absolute sky brightness maps from AKARI. This photometry is compared with flux-density predictions based on photospheric models for these stars. We obtain a robust noise estimate by fitting the flux distribution per map pixel histogram for the area around the stars, scaling it for the applied aperture size and correcting for noise correlation. Results: For 15 stars we obtain reliable photometry in at least one PACS filter, and for 11 stars we achieve this in all three PACS filters (70, 100, 160 μm). Faintest fluxes, for which the photometry still has good quality, are about 10-20 mJy with scan map photometry. The photometry of seven stars is consistent with models or flux predictions for pure photospheric emission, making them good primary standard candidates. Two stars exhibit source-intrinsic far-infrared excess: β Gem (Pollux), being the host star of a confirmed Jupiter-size exoplanet, due to emission of an associated dust disk, and η Dra due to dust emission in a binary system with a K1 dwarf. The investigation of the 160 μm sky background and environment of four sources reveals significant sky confusion prohibiting the determination of an accurate stellar flux at this wavelength. As a good model

  16. Photometric normalization of LROC WAC images

    Science.gov (United States)

    Sato, H.; Denevi, B.; Robinson, M. S.; Hapke, B. W.; McEwen, A. S.; LROC Science Team

    2010-12-01

    The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) acquires near global coverage on a monthly basis. The WAC is a push frame sensor with a 90° field of view (FOV) in BW mode and 60° FOV in 7-color mode (320 nm to 689 nm). WAC images are acquired during each orbit in 10° latitude segments with cross track coverage of ~50 km. Before mosaicking, WAC images are radiometrically calibrated to remove instrumental artifacts and to convert at sensor radiance to I/F. Images are also photometrically normalized to common viewing and illumination angles (30° phase), a challenge due to the wide angle nature of the WAC where large differences in phase angle are observed in a single image line (±30°). During a single month the equatorial incidence angle drifts about 28° and over the course of ~1 year the lighting completes a 360° cycle. The light scattering properties of the lunar surface depend on incidence(i), emission(e), and phase(p) angles as well as soil properties such as single-scattering albedo and roughness that vary with terrain type and state of maturity [1]. We first tested a Lommel-Seeliger Correction (LSC) [cos(i)/(cos(i) + cos(e))] [2] with a phase function defined by an exponential decay plus 4th order polynomial term [3] which did not provide an adequate solution. Next we employed a LSC with an exponential 2nd order decay phase correction that was an improvement, but still exhibited unacceptable frame-to-frame residuals. In both cases we fitted the LSC I/F vs. phase angle to derive the phase corrections. To date, the best results are with a lunar-lambert function [4] with exponential 2nd order decay phase correction (LLEXP2) [(A1exp(B1p)+A2exp(B2p)+A3) * cos(i)/(cos(e) + cos(i)) + B3cos(i)]. We derived the parameters for the LLEXP2 from repeat imaging of a small region and then corrected that region with excellent results. When this correction was applied to the whole Moon the results were less than optimal - no surprise given the

  17. Image acquisition for the pediatric radiology PACS module

    International Nuclear Information System (INIS)

    Ho, B.K.; Morioka, C.; Mankovich, N.J.; Stewart, B.; Huang, H.K.

    1987-01-01

    The prototype PACS module implemented at UCLA's pediatric radiology section has multi-modality access to image data from any of the three types of sources: digital modalities (i.e. CT, MR, and DSA), the Fuji Computed Radiography unit (FCR), and laser film digitizers. An interface unit was built to facilitate real-time data transfer from the FCR to the VAX11/750 which serves as the PACS host computer. The design of the interface unit, methods for linking to digital modalities, and characteristics of two film digitizers are described

  18. PACS and the digital storage of medical images

    International Nuclear Information System (INIS)

    Perry, J.R.; Johnston, R.E.; Pizer, S.M.; Lowendorf, D.D.; Rogers, D.C.; Thompson, B.C.; Parrish, D.M.; Brenton, B.C.; Staab, E.V.

    1986-01-01

    An application of computers in medicine is developing wherein large amounts of digital information in the form of images must be stored, retrieved, and displayed quickly. In radiology this application most commonly goes by the acronym PACS which stands for picture archival and communications system. Estimates of the storage requirements for radiologic images strongly suggest that we should think in terms of terabytes per year for a 150,000 procedure/year, 600 bed hospital. Transmission of patient image data files (a single X-ray image pair may be 12.6 Mbytes) arouses concern over transmission speeds, user waiting tolerances and a communications standard. An important accord is being reached between users and equipment manufacturers in radiology for a standard communications protocol, called the proposed ACR-NEMA standard. Features of PACS which require high speed computational abilities include a lexicon for report generation and image reconstruction, compression, enhancement and 3D display

  19. PACS and diagnostic imaging service delivery-A UK perspective

    International Nuclear Information System (INIS)

    Sutton, Laurence N.

    2011-01-01

    This review sets out the current position with regard to the implementation of PACS throughout the United Kingdom and the impact this has had on improving patient care. In December 2007 England had implemented full hospital-wide PACS in all hospitals: a major achievement in the relatively short time period of three years. The different approaches used by each country of the UK to achieve full national PACS are described in addition to the current issues with the sharing of images and reports across different healthcare organisations with regard to technical solutions, clinical safety and governance. The review gives insight into the changing methods of service delivery to address increasing demand pressures on diagnostic imaging services and how the national PACS implementation, specifically in England, has made a significant contribution to measures to improve efficiencies. The role of Teleradiology is discussed in the context of supporting local patient services rather than undermining them and the concept of cross-healthcare reporting 'Grids' is described. Finally, in the summary it is recognised that the vast wealth of knowledge accumulated during the national implementations has placed the UK in a strong position to facilitate full national data sharing across all healthcare organisations to improve patient care.

  20. Ethernet image communication performance in a multimodal PACS network

    International Nuclear Information System (INIS)

    Lou, S.L.; Valentino, D.J.; Chan, K.K.; Huang, H.K.

    1989-01-01

    The authors have evaluated the performance of an Ethernet network in a multimodal picture archiving and communications system (PACS) environment. The study included measurements between Sun workstations and PC- AT computers running communication software at the TCP level. First they initiated image transfers between two workstations, a server and a client. Next, they successively added clients to transfer images to the server and they measured degradation in network performance. Finally, they initiated image transfers between pairs of workstations and again measured performance degradation. The results of the authors' experiments indicate that Ethernet is suitable for image communication only in limited network situations. They discuss how to maximize network performance given these constraints

  1. Photometric Modeling of Simulated Surace-Resolved Bennu Images

    Science.gov (United States)

    Golish, D.; DellaGiustina, D. N.; Clark, B.; Li, J. Y.; Zou, X. D.; Bennett, C. A.; Lauretta, D. S.

    2017-12-01

    The Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) is a NASA mission to study and return a sample of asteroid (101955) Bennu. Imaging data from the mission will be used to develop empirical surface-resolved photometric models of Bennu at a series of wavelengths. These models will be used to photometrically correct panchromatic and color base maps of Bennu, compensating for variations due to shadows and photometric angle differences, thereby minimizing seams in mosaicked images. Well-corrected mosaics are critical to the generation of a global hazard map and a global 1064-nm reflectance map which predicts LIDAR response. These data products directly feed into the selection of a site from which to safely acquire a sample. We also require photometric correction for the creation of color ratio maps of Bennu. Color ratios maps provide insight into the composition and geological history of the surface and allow for comparison to other Solar System small bodies. In advance of OSIRIS-REx's arrival at Bennu, we use simulated images to judge the efficacy of both the photometric modeling software and the mission observation plan. Our simulation software is based on USGS's Integrated Software for Imagers and Spectrometers (ISIS) and uses a synthetic shape model, a camera model, and an empirical photometric model to generate simulated images. This approach gives us the flexibility to create simulated images of Bennu based on analog surfaces from other small Solar System bodies and to test our modeling software under those conditions. Our photometric modeling software fits image data to several conventional empirical photometric models and produces the best fit model parameters. The process is largely automated, which is crucial to the efficient production of data products during proximity operations. The software also produces several metrics on the quality of the observations themselves, such as surface coverage and the

  2. Photometric imaging in particle size measurement and surface visualization.

    Science.gov (United States)

    Sandler, Niklas

    2011-09-30

    The aim of this paper is to give an insight into photometric particle sizing approaches, which differ from the typical particle size measurement of dispersed particles. These approaches can often be advantageous especially for samples that are moist or cohesive, when dispersion of particles is difficult or sometimes impossible. The main focus of this paper is in the use of photometric stereo imaging. The technique allows the reconstruction of three-dimensional images of objects using multiple light sources in illumination. The use of photometric techniques is demonstrated in at-line measurement of granules and on-line measurement during granulation and dry milling. Also, surface visualization and roughness measurements are briefly discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. DICOM-compliant PACS with CD-based image archival

    Science.gov (United States)

    Cox, Robert D.; Henri, Christopher J.; Rubin, Richard K.; Bret, Patrice M.

    1998-07-01

    This paper describes the design and implementation of a low- cost PACS conforming to the DICOM 3.0 standard. The goal was to provide an efficient image archival and management solution on a heterogeneous hospital network as a basis for filmless radiology. The system follows a distributed, client/server model and was implemented at a fraction of the cost of a commercial PACS. It provides reliable archiving on recordable CD and allows access to digital images throughout the hospital and on the Internet. Dedicated servers have been designed for short-term storage, CD-based archival, data retrieval and remote data access or teleradiology. The short-term storage devices provide DICOM storage and query/retrieve services to scanners and workstations and approximately twelve weeks of 'on-line' image data. The CD-based archival and data retrieval processes are fully automated with the exception of CD loading and unloading. The system employs lossless compression on both short- and long-term storage devices. All servers communicate via the DICOM protocol in conjunction with both local and 'master' SQL-patient databases. Records are transferred from the local to the master database independently, ensuring that storage devices will still function if the master database server cannot be reached. The system features rules-based work-flow management and WWW servers to provide multi-platform remote data access. The WWW server system is distributed on the storage, retrieval and teleradiology servers allowing viewing of locally stored image data directly in a WWW browser without the need for data transfer to a central WWW server. An independent system monitors disk usage, processes, network and CPU load on each server and reports errors to the image management team via email. The PACS was implemented using a combination of off-the-shelf hardware, freely available software and applications developed in-house. The system has enabled filmless operation in CT, MR and ultrasound within

  4. A PHOTOMETRIC ANALYSIS OF SEVENTEEN BINARY STARS USING SPECKLE IMAGING

    International Nuclear Information System (INIS)

    Davidson, James W.; Baptista, Brian J.; Horch, Elliott P.; Franz, Otto; Van Altena, William F.

    2009-01-01

    Magnitude differences obtained from speckle imaging are used in combination with other data in the literature to place the components of binary star systems on the H-R diagram. Isochrones are compared with the positions obtained, and a best-fit isochrone is determined for each system, yielding both masses of the components as well as an age range consistent with the system parameters. Seventeen systems are studied, 12 of which were observed with the 0.6 m Lowell-Tololo Telescope at Cerro Tololo Inter-American Observatory and six of which were observed with the WIYN 3.5 m Telescope (The WIYN Observatory is a joint facility of the University of Wisconsin-Madison, Indiana University, Yale University, and the National Optical Astronomy Observatories) at Kitt Peak. One system was observed from both sites. In comparing photometric masses to mass information from orbit determinations, we find that the photometric masses agree very well with the dynamical masses, and are generally more precise. For three systems, no dynamical masses exist at present, and therefore the photometrically determined values are the first mass estimates derived for these components.

  5. CT and MR imaging acquisition performance in a neuroradiology PACS module 1-year clinical experience

    International Nuclear Information System (INIS)

    Lou, S.L.; Loloyan, M.; Weinberg, W.S.; Valentino, D.J.; Lufkin, R.B.; Hanafee, W.N.; Bentson, J.; Jabour, B.A.; Huang, H.K.

    1990-01-01

    This paper analyzes the operational efficiency of our neuroradiology PACS compared with conventional film-based management systems. The authors neuroradiology PACS module has been in clinical evaluation for 6 months. Three SUN microcomputers, two PC/ATs, and an automated optical disk library are connected through Ethernet. Software implemented at the TCP/IP level is used to transfer images from MR imagers and CT scanners to a viewing station. Performance measurements include the time elapsed at each stage of the system

  6. Development and practice for a PACS-based interactive teaching model for CT image

    International Nuclear Information System (INIS)

    Tian Junzhang; Jiang Guihua; Zheng Liyin; Wang Ling; Wenhua; Liang Lianbao

    2002-01-01

    Objective: To explore the interactive teaching model for CT imaging based on PACS, and provide the clinician and young radiologist with continued medical education. Methods: 100 M trunk net was adopted in PACS and 10 M was exchanged on desktop. Teaching model was installed in browse and diagnosis workstation. Teaching contents were classified according to region and managed according to branch model. Text data derived from authoritative textbooks, monograph, and periodicals. Imaging data derived from cases proved by pathology and clinic. The data were obtained through digital camera and scanner or from PACS. After edited and transformed into standard digital image through DICOM server, they were saved in HD of PACS image server with file form. Results: Teaching model for CT imaging provided kinds of cases of CT sign, clinic characteristics, pathology and distinguishing diagnosis. Normal section anatomy, typical image, and its notation could be browsed real time. Teaching model for CT imaging could provide reference to teaching, diagnosis and report. Conclusion: PACS-based teaching model for CT imaging could provide interactive teaching and scientific research tool and improve work quality and efficiency

  7. Photometric Calibration of the Gemini South Adaptive Optics Imager

    Science.gov (United States)

    Stevenson, Sarah Anne; Rodrigo Carrasco Damele, Eleazar; Thomas-Osip, Joanna

    2017-01-01

    The Gemini South Adaptive Optics Imager (GSAOI) is an instrument available on the Gemini South telescope at Cerro Pachon, Chile, utilizing the Gemini Multi-Conjugate Adaptive Optics System (GeMS). In order to allow users to easily perform photometry with this instrument and to monitor any changes in the instrument in the future, we seek to set up a process for performing photometric calibration with standard star observations taken across the time of the instrument’s operation. We construct a Python-based pipeline that includes IRAF wrappers for reduction and combines the AstroPy photutils package and original Python scripts with the IRAF apphot and photcal packages to carry out photometry and linear regression fitting. Using the pipeline, we examine standard star observations made with GSAOI on 68 nights between 2013 and 2015 in order to determine the nightly photometric zero points in the J, H, Kshort, and K bands. This work is based on observations obtained at the Gemini Observatory, processed using the Gemini IRAF and gemini_python packages, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).

  8. Bifurcations in two-image photometric stereo for orthogonal illuminations

    Science.gov (United States)

    Kozera, R.; Prokopenya, A.; Noakes, L.; Śluzek, A.

    2017-07-01

    This paper discusses the ambiguous shape recovery in two-image photometric stereo for a Lambertian surface. The current uniqueness analysis refers to linearly independent light-source directions p = (0, 0, -1) and q arbitrary. For this case necessary and sufficient condition determining ambiguous reconstruction is governed by a second-order linear partial differential equation with constant coefficients. In contrast, a general position of both non-colinear illumination directions p and q leads to a highly non-linear PDE which raises a number of technical difficulties. As recently shown, the latter can also be handled for another family of orthogonal illuminations parallel to the OXZ-plane. For the special case of p = (0, 0, -1) a potential ambiguity stems also from the possible bifurcations of sub-local solutions glued together along a curve defined by an algebraic equation in terms of the data. This paper discusses the occurrence of similar bifurcations for such configurations of orthogonal light-source directions. The discussion to follow is supplemented with examples based on continuous reflectance map model and generated synthetic images.

  9. Overview of PACS

    Science.gov (United States)

    Vanden Brink, John A.

    1995-08-01

    Development of the DICOM standard and incremental developments in workstation, network, compression, archiving, and digital x-ray technology have produced cost effective image communication possibilities for selected medical applications. The emerging markets include modality PACS, mini PACS, and teleradiology. Military and VA programs lead the way in the move to adopt PACS technology. Commercial markets for PACS components and PAC systems are at LR400 million growing to LR500 million in 1996.

  10. From PACS to Web-based ePR system with image distribution for enterprise-level filmless healthcare delivery.

    Science.gov (United States)

    Huang, H K

    2011-07-01

    The concept of PACS (picture archiving and communication system) was initiated in 1982 during the SPIE medical imaging conference in New Port Beach, CA. Since then PACS has been matured to become an everyday clinical tool for image archiving, communication, display, and review. This paper follows the continuous development of PACS technology including Web-based PACS, PACS and ePR (electronic patient record), enterprise PACS to ePR with image distribution (ID). The concept of large-scale Web-based enterprise PACS and ePR with image distribution is presented along with its implementation, clinical deployment, and operation. The Hong Kong Hospital Authority's (HKHA) integration of its home-grown clinical management system (CMS) with PACS and ePR with image distribution is used as a case study. The current concept and design criteria of the HKHA enterprise integration of the CMS, PACS, and ePR-ID for filmless healthcare delivery are discussed, followed by its work-in-progress and current status.

  11. Enterprise-wide PACS: beyond radiology, an architecture to manage all medical images.

    Science.gov (United States)

    Bandon, David; Lovis, Christian; Geissbühler, Antoine; Vallée, Jean-Paul

    2005-08-01

    Picture archiving and communication systems (PACS) have the vocation to manage all medical images acquired within the hospital. To address the various situations encountered in the imaging specialties, the traditional architecture used for the radiology department has to evolve. We present our preliminarily results toward an enterprise-wide PACS intended to support all kind of image production in medicine, from biomolecular images to whole-body pictures. Our solution is based on an existing radiologic PACS system from which images are distributed through an electronic patient record to all care facilities. This platform is enriched with a flexible integration framework supporting digital image communication in medicine (DICOM) and DICOM-XML formats. In addition, a generic workflow engine highly customizable is used to drive work processes. Echocardiology; hematology; ear, nose, and throat; and dermatology, including wounds, follow-up is the first implemented extensions outside of radiology. We also propose a global strategy for further developments based on three possible architectures for an enterprise-wide PACS.

  12. Whole-slide imaging in pathology: the potential impact on PACS

    Science.gov (United States)

    Horii, Steven C.

    2007-03-01

    Pathology, the medical specialty charged with the evaluation of macroscopic and microscopic aspects of disease, is increasingly turning to digital imaging. While the conventional tissue blocks and glass slides form an "archive" that pathology departments must maintain, digital images acquired from microscopes or digital slide scanners are increasingly used for telepathology, consultation, and intra-facility communication. Since many healthcare facilities are moving to "enterprise PACS" with departments in addition to radiology using the infrastructure of such systems, some understanding of the potential of whole-slide digital images is important. Network and storage designers, in particular, are very likely to be impacted if a significant number of such images are to be moved on, or stored (even temporarily) in, enterprise PACS. As an example, a typical commercial whole-slide imaging system typically generates 15 gigabytes per slide scanned (per focal plane). Many of these whole-slide scanners have a throughput of 1000 slides per day. If that full capacity is used and all the resulting digital data is moved to the enterprise PACS, it amounts to 15 terabytes per day; the amount of data a large radiology department might generate in a year or two. This paper will review both the clinical scenarios of whole-slide imaging as well as the resulting data volumes. The author will emphasize the potential PACS infrastructure impact of such huge data volumes.

  13. Lunar photometric modelling with SMART-1/AMIE imaging data

    International Nuclear Information System (INIS)

    Wilkman, O.; Muinonen, K.; Videen, G.; Josset, J.-L.; Souchon, A.

    2014-01-01

    We investigate the light-scattering properties of the lunar mare areas. A large photometric dataset was extracted from images taken by the AMIE camera on board the SMART-1 spacecraft. Inter-particle shadowing effects in the regolith are modelled using ray-tracing simulations, and then a phase function is fit to the data using Bayesian techniques and Markov chain Monte Carlo. Additionally, the data are fit with phase functions computed from radiative-transfer coherent-backscatter (RT-CB) simulations. The results indicate that the lunar photometry, including both the opposition effect and azimuthal effects, can be explained well with a combination of inter-particle shadowing and coherent backscattering. Our results produce loose constraints on the mare physical properties. The RT-CB results indicate that the scattering volume element is optically thick. In both the Bayesian analysis and the RT-CB fit, models with lower packing density and/or higher surface roughness always produce better fits to the data than densely packed, smoother ones

  14. Investigation on network utilization efficiency and image transmission time for the PACS network

    International Nuclear Information System (INIS)

    Tawara, K.; Nishihara, E.; Komatsu, K.I.

    1987-01-01

    The authors investigated the following features of a PACS network: (1) network utilization efficiency and (2) image transmission time. They changed the following parameters, which the two items shown above depend on: (1) transfer rate between imaging equipment and network (10 kB/econd-8 MB/second), (2) network transmission speed (100 kB/second-50 MB/second), (3) packet length (10 kB-4 MB), and (4) message length (image data) (64 kB-4 MB). As a result, a conventional-type network cannot meet a need for PACS. To solve this problem, the authors propose a multiplexed network that consists of the high-speed network for image transmission and the conventional speed of control network for commands and shorter messages. If the packet length of the image network is designed to be variable, they can choose an optimum packet length for image transmission

  15. Digital imaging and electronic patient records in pathology using an integrated department information system with PACS.

    Science.gov (United States)

    Kalinski, Thomas; Hofmann, Harald; Franke, Dagmar-Sybilla; Roessner, Albert

    2002-01-01

    Picture archiving and communication systems have been widely used in radiology thus far. Owing to the progress made in digital photo technology, their use in medicine opens up further opportunities. In the field of pathology, digital imaging offers new possiblities for the documentation of macroscopic and microscopic findings. Digital imaging has the advantage that the data is permanently and readily available, independent of conventional archives. In the past, PACS was a separate entity. Meanwhile, however, PACS has been integrated in DIS, the department information system, which was also run separately in former times. The combination of these two systems makes the administration of patient data, findings and images easier. Moreover, thanks to the introduction of special communication standards, a data exchange between different department information systems and hospital information systems (HIS) is possible. This provides the basis for a communication platform in medicine, constituting an electronic patient record (EPR) that permits an interdisciplinary treatment of patients by providing data of findings and images from clinics treating the same patient. As the pathologic diagnosis represents a central and often therapy-determining component, it is of utmost importance to add pathologic diagnoses to the EPR. Furthermore, the pathologist's work is considerably facilitated when he is able to retrieve additional data from the patient file. In this article, we describe our experience gained with the combined PACS and DIS systems recently installed at the Department of Pathology, University of Magdeburg. Moreover, we evaluate the current situation and future prospects for PACS in pathology.

  16. Evaluation of video capture equipment for secondary image acquisition in the PACS.

    Science.gov (United States)

    Sukenobu, Yoshiharu; Sasagaki, Michihiro; Hirabuki, Norio; Naito, Hiroaki; Narumi, Yoshifumi; Inamura, Kiyonari

    2002-01-01

    There are many cases in which picture archiving and communication systems (PACS) are built with old-type existing modalities with no DICOM output. One of the methods for interfacing them to the PACS is to implement video capture (/ frame grabber) equipment. This equipment takes analog video signal output from medical imaging modalities, and amplitude of the video signal is A/D converted and supplied to the PACS. In this report, we measured and evaluated the accuracy at which this video capture equipment could capture the image. From the physical evaluation, we found the pixel values of an original image and its captured image were almost equal in gray level from 20%-90%. The change in the pixel values of a captured image was +/-3 on average. The change of gray level concentration was acceptable and had an average standard deviation of around 0.63. As for resolution, the degradation was observed at the highest physical level. In a subjective evaluation, the evaluation value of the CT image had a grade of 2.81 on the average (the same quality for a reference image was set to a grade of 3.0). Abnormalities in heads, chests, and abdomens were judged not to influence diagnostic accuracy. Some small differences were seen when comparing captured and reference images, but they are recognized as having no influence on the diagnoses.

  17. Remote consultation and diagnosis in medical imaging using a global PACS backbone network

    Science.gov (United States)

    Martinez, Ralph; Sutaria, Bijal N.; Kim, Jinman; Nam, Jiseung

    1993-10-01

    A Global PACS is a national network which interconnects several PACS networks at medical and hospital complexes using a national backbone network. A Global PACS environment enables new and beneficial operations between radiologists and physicians, when they are located in different geographical locations. One operation allows the radiologist to view the same image folder at both Local and Remote sites so that a diagnosis can be performed. The paper describes the user interface, database management, and network communication software which has been developed in the Computer Engineering Research Laboratory and Radiology Research Laboratory. Specifically, a design for a file management system in a distributed environment is presented. In the remote consultation and diagnosis operation, a set of images is requested from the database archive system and sent to the Local and Remote workstation sites on the Global PACS network. Viewing the same images, the radiologists use pointing overlay commands, or frames to point out features on the images. Each workstation transfers these frames, to the other workstation, so that an interactive session for diagnosis takes place. In this phase, we use fixed frames and variable size frames, used to outline an object. The data pockets for these frames traverses the national backbone in real-time. We accomplish this feature by using TCP/IP protocol sockets for communications. The remote consultation and diagnosis operation has been tested in real-time between the University Medical Center and the Bowman Gray School of Medicine at Wake Forest University, over the Internet. In this paper, we show the feasibility of the operation in a Global PACS environment. Future improvements to the system will include real-time voice and interactive compressed video scenarios.

  18. On-line monitoring of fluid bed granulation by photometric imaging.

    Science.gov (United States)

    Soppela, Ira; Antikainen, Osmo; Sandler, Niklas; Yliruusi, Jouko

    2014-11-01

    This paper introduces and discusses a photometric surface imaging approach for on-line monitoring of fluid bed granulation. Five granule batches consisting of paracetamol and varying amounts of lactose and microcrystalline cellulose were manufactured with an instrumented fluid bed granulator. Photometric images and NIR spectra were continuously captured on-line and particle size information was extracted from them. Also key process parameters were recorded. The images provided direct real-time information on the growth, attrition and packing behaviour of the batches. Moreover, decreasing image brightness in the drying phase was found to indicate granule drying. The changes observed in the image data were also linked to the moisture and temperature profiles of the processes. Combined with complementary process analytical tools, photometric imaging opens up possibilities for improved real-time evaluation fluid bed granulation. Furthermore, images can give valuable insight into the behaviour of excipients or formulations during product development. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Making the PACS workstation a browser of image processing software: a feasibility study using inter-process communication techniques.

    Science.gov (United States)

    Wang, Chunliang; Ritter, Felix; Smedby, Orjan

    2010-07-01

    To enhance the functional expandability of a picture archiving and communication systems (PACS) workstation and to facilitate the integration of third-part image-processing modules, we propose a browser-server style method. In the proposed solution, the PACS workstation shows the front-end user interface defined in an XML file while the image processing software is running in the background as a server. Inter-process communication (IPC) techniques allow an efficient exchange of image data, parameters, and user input between the PACS workstation and stand-alone image-processing software. Using a predefined communication protocol, the PACS workstation developer or image processing software developer does not need detailed information about the other system, but will still be able to achieve seamless integration between the two systems and the IPC procedure is totally transparent to the final user. A browser-server style solution was built between OsiriX (PACS workstation software) and MeVisLab (Image-Processing Software). Ten example image-processing modules were easily added to OsiriX by converting existing MeVisLab image processing networks. Image data transfer using shared memory added communication based on IPC techniques is an appealing method that allows PACS workstation developers and image processing software developers to cooperate while focusing on different interests.

  20. The guarantee of the consistency of patient information through modality worklist among PACS, RIS and imaging equipments

    International Nuclear Information System (INIS)

    Luo Min; Peng Chenglin; Wang Xiaolin; Luo Song; Lei Wenyong; Wang Kang; Wang Xuejian; Wen Hongyu; Wu Hongxing

    2003-01-01

    Objective: To realize the consistency of patient information through modality worklist among picture archiving and communication system (PACS), radiology information systems (RIS), and imaging equipments. Methods: Many digital modalities including GE Signa 1.5 T MR system, digital mammography, Agfa digital radiography, computed radiography, GE CT, and etc were installed in our hospital. Since the GE PACS system was in English version, the images were saved and the information was managed to PACS without a truly worklist. Two months later, while still using the previous PACS, the consistency of patient information was resolved through modality worklist by adopting the international advanced approach to realize thread worklist of digital imaging and communication in medicine. The information in Chinese will be transformed into information in English in RIS system and saved as the English information to worklist. Results: After the implementation and integration of PACS and RIS was achieved in my hospital, the consistency of patient information was guaranteed through modality worklist between RIS and imaging equipments and the first-rate effect was acquired. The patient information could be checked, edited, and created by using the Chinese RIS system on all diagnostic workstations. Conclusion: The consistency of patient information through modality worklist was realized among PACS, RIS, and imaging equipments, yet at present, the question of guarantee the consistency of patient information must be thought over in PACS building

  1. PACS in nuclear medicine

    International Nuclear Information System (INIS)

    Kang, Keon Wook

    2000-01-01

    PACS (Picture Archiving and Communication System) is being rapidly spread and installed in many hospitals, but most of the system do not include nuclear medicine field. Although additional costs of hardware for nuclear medicine PACS is low, the complexity in developing viewing software and little market have made the nuclear medicine PACS not popular. Most PACS utilize DICOM 3.0 as standard format, but standard format in nuclear medicine has been Interfile. Interfile should be converted into DICOM format if nuclear images are to be stored and visualized in most PACS. Nowadays, many vendors supply the DICOM option in gamma camera and PET. Several hospitals in Korea have already installed nucler PACS with DICOM, but only the screen captured images are supplied. Software for visualizing pseudo-color with color lookup tables and expressing with volume view should be developed to fulfill the demand of referring physicians and nuclear medicine physicians. PACS is going to integrate not only radiologic images but also endoscopic and pathologic images. Web and PC based PACS is now a trend and is much compatible with nuclear medicine PACS. Most important barrier for nuclear medicine PACS that we encounter is not a technical problem, but indifference of investor such as administrator of hospital or PACS. Now it is time to support and invest for the development of nuclear medicine PACS

  2. CALIPSO: an interactive image analysis software package for desktop PACS workstations

    Science.gov (United States)

    Ratib, Osman M.; Huang, H. K.

    1990-07-01

    The purpose of this project is to develop a low cost workstation for quantitative analysis of multimodality images using a Macintosh II personal computer. In the current configuration the Macintosh operates as a stand alone workstation where images are imported either from a central PACS server through a standard Ethernet network or recorded through video digitizer board. The CALIPSO software developed contains a large variety ofbasic image display and manipulation tools. We focused our effort however on the design and implementation ofquantitative analysis methods that can be applied to images from different imaging modalities. Analysis modules currently implemented include geometric and densitometric volumes and ejection fraction calculation from radionuclide and cine-angiograms Fourier analysis ofcardiac wall motion vascular stenosis measurement color coded parametric display of regional flow distribution from dynamic coronary angiograms automatic analysis ofmyocardial distribution ofradiolabelled tracers from tomoscintigraphic images. Several of these analysis tools were selected because they use similar color coded andparametric display methods to communicate quantitative data extracted from the images. 1. Rationale and objectives of the project Developments of Picture Archiving and Communication Systems (PACS) in clinical environment allow physicians and radiologists to assess radiographic images directly through imaging workstations (''). This convenient access to the images is often limited by the number of workstations available due in part to their high cost. There is also an increasing need for quantitative analysis ofthe images. During thepast decade

  3. The Dynamic Photometric Stereo Method Using a Multi-Tap CMOS Image Sensor †

    Science.gov (United States)

    Yoda, Takuya; Nagahara, Hajime; Taniguchi, Rin-ichiro; Kagawa, Keiichiro; Yasutomi, Keita; Kawahito, Shoji

    2018-01-01

    The photometric stereo method enables estimation of surface normals from images that have been captured using different but known lighting directions. The classical photometric stereo method requires at least three images to determine the normals in a given scene. However, this method cannot be applied to dynamic scenes because it is assumed that the scene remains static while the required images are captured. In this work, we present a dynamic photometric stereo method for estimation of the surface normals in a dynamic scene. We use a multi-tap complementary metal-oxide-semiconductor (CMOS) image sensor to capture the input images required for the proposed photometric stereo method. This image sensor can divide the electrons from the photodiode from a single pixel into the different taps of the exposures and can thus capture multiple images under different lighting conditions with almost identical timing. We implemented a camera lighting system and created a software application to enable estimation of the normal map in real time. We also evaluated the accuracy of the estimated surface normals and demonstrated that our proposed method can estimate the surface normals of dynamic scenes. PMID:29510599

  4. The Dynamic Photometric Stereo Method Using a Multi-Tap CMOS Image Sensor.

    Science.gov (United States)

    Yoda, Takuya; Nagahara, Hajime; Taniguchi, Rin-Ichiro; Kagawa, Keiichiro; Yasutomi, Keita; Kawahito, Shoji

    2018-03-05

    The photometric stereo method enables estimation of surface normals from images that have been captured using different but known lighting directions. The classical photometric stereo method requires at least three images to determine the normals in a given scene. However, this method cannot be applied to dynamic scenes because it is assumed that the scene remains static while the required images are captured. In this work, we present a dynamic photometric stereo method for estimation of the surface normals in a dynamic scene. We use a multi-tap complementary metal-oxide-semiconductor (CMOS) image sensor to capture the input images required for the proposed photometric stereo method. This image sensor can divide the electrons from the photodiode from a single pixel into the different taps of the exposures and can thus capture multiple images under different lighting conditions with almost identical timing. We implemented a camera lighting system and created a software application to enable estimation of the normal map in real time. We also evaluated the accuracy of the estimated surface normals and demonstrated that our proposed method can estimate the surface normals of dynamic scenes.

  5. PACS for surgery and interventional radiology: Features of a Therapy Imaging and Model Management System (TIMMS)

    International Nuclear Information System (INIS)

    Lemke, Heinz U.; Berliner, Leonard

    2011-01-01

    Appropriate use of information and communication technology (ICT) and mechatronic (MT) systems is viewed by many experts as a means to improve workflow and quality of care in the operating room (OR). This will require a suitable information technology (IT) infrastructure, as well as communication and interface standards, such as specialized extensions of DICOM, to allow data interchange between surgical system components in the OR. A design of such an infrastructure, sometimes referred to as surgical PACS, but better defined as a Therapy Imaging and Model Management System (TIMMS), will be introduced in this article. A TIMMS should support the essential functions that enable and advance image guided therapy, and in the future, a more comprehensive form of patient-model guided therapy. Within this concept, the 'image-centric world view' of the classical PACS technology is complemented by an IT 'model-centric world view'. Such a view is founded in the special patient modelling needs of an increasing number of modern surgical interventions as compared to the imaging intensive working mode of diagnostic radiology, for which PACS was originally conceptualised and developed. The modelling aspects refer to both patient information and workflow modelling. Standards for creating and integrating information about patients, equipment, and procedures are vitally needed when planning for an efficient OR. The DICOM Working Group 24 (WG-24) has been established to develop DICOM objects and services related to image and model guided surgery. To determine these standards, it is important to define step-by-step surgical workflow practices and create interventional workflow models per procedures or per variable cases. As the boundaries between radiation therapy, surgery and interventional radiology are becoming less well-defined, precise patient models will become the greatest common denominator for all therapeutic disciplines. In addition to imaging, the focus of WG-24 is to serve

  6. PACS for surgery and interventional radiology: features of a Therapy Imaging and Model Management System (TIMMS).

    Science.gov (United States)

    Lemke, Heinz U; Berliner, Leonard

    2011-05-01

    Appropriate use of information and communication technology (ICT) and mechatronic (MT) systems is viewed by many experts as a means to improve workflow and quality of care in the operating room (OR). This will require a suitable information technology (IT) infrastructure, as well as communication and interface standards, such as specialized extensions of DICOM, to allow data interchange between surgical system components in the OR. A design of such an infrastructure, sometimes referred to as surgical PACS, but better defined as a Therapy Imaging and Model Management System (TIMMS), will be introduced in this article. A TIMMS should support the essential functions that enable and advance image guided therapy, and in the future, a more comprehensive form of patient-model guided therapy. Within this concept, the "image-centric world view" of the classical PACS technology is complemented by an IT "model-centric world view". Such a view is founded in the special patient modelling needs of an increasing number of modern surgical interventions as compared to the imaging intensive working mode of diagnostic radiology, for which PACS was originally conceptualised and developed. The modelling aspects refer to both patient information and workflow modelling. Standards for creating and integrating information about patients, equipment, and procedures are vitally needed when planning for an efficient OR. The DICOM Working Group 24 (WG-24) has been established to develop DICOM objects and services related to image and model guided surgery. To determine these standards, it is important to define step-by-step surgical workflow practices and create interventional workflow models per procedures or per variable cases. As the boundaries between radiation therapy, surgery and interventional radiology are becoming less well-defined, precise patient models will become the greatest common denominator for all therapeutic disciplines. In addition to imaging, the focus of WG-24 is to serve

  7. Towards a semantic PACS: Using Semantic Web technology to represent imaging data.

    Science.gov (United States)

    Van Soest, Johan; Lustberg, Tim; Grittner, Detlef; Marshall, M Scott; Persoon, Lucas; Nijsten, Bas; Feltens, Peter; Dekker, Andre

    2014-01-01

    The DICOM standard is ubiquitous within medicine. However, improved DICOM semantics would significantly enhance search operations. Furthermore, databases of current PACS systems are not flexible enough for the demands within image analysis research. In this paper, we investigated if we can use Semantic Web technology, to store and represent metadata of DICOM image files, as well as linking additional computational results to image metadata. Therefore, we developed a proof of concept containing two applications: one to store commonly used DICOM metadata in an RDF repository, and one to calculate imaging biomarkers based on DICOM images, and store the biomarker values in an RDF repository. This enabled us to search for all patients with a gross tumor volume calculated to be larger than 50 cc. We have shown that we can successfully store the DICOM metadata in an RDF repository and are refining our proof of concept with regards to volume naming, value representation, and the applications themselves.

  8. A Photometric Stereo Using Re-Projected Images for Active Stereo Vision System

    Directory of Open Access Journals (Sweden)

    Keonhwa Jung

    2017-10-01

    Full Text Available In optical 3D shape measurement, stereo vision with structured light can measure 3D scan data with high accuracy and is used in many applications, but fine surface detail is difficult to obtain. On the other hand, photometric stereo can capture surface details but has disadvantages, in that its 3D data accuracy drops and it requires multiple light sources. When the two measurement methods are combined, more accurate 3D scan data and detailed surface features can be obtained at the same time. In this paper, we present a 3D optical measurement technique that uses re-projection of images to implement photometric stereo without an external light source. 3D scan data is enhanced by combining normal vector from this photometric stereo method, and the result is evaluated with the ground truth.

  9. Does use of a PACS increase the number of images per study? A case study in ultrasound.

    Science.gov (United States)

    Horii, Steven; Nisenbaum, Harvey; Farn, James; Coleman, Beverly; Rowling, Susan; Langer, Jill; Jacobs, Jill; Arger, Peter; Pinheiro, Lisa; Klein, Wendy; Reber, Michele; Iyoob, Christopher

    2002-03-01

    The purpose of this study was to determine if the use of a picture archiving and communications system (PACS) in ultrasonography increased the number of images acquired per examination. The hypothesis that such an increase does occur was based on anecdotal information; this study sought to test the hypothesis. A random sample of all ultrasound examination types was drawn from the period 1998 through 1999. The ultrasound PACS in use (ACCESS; Kodak Health Information Systems, Dallas, TX) records the number of grayscale and color images saved as part of each study. Each examination in the sample was checked in the ultrasound PACS database,.and the number of grayscale and color images was recorded. The comparison film-based sample was drawn from the period 1994 through 1995. The number of examinations of each type selected was based on the overall statistics of the section; that is, the sample was designed to represent the approximate frequency with which the various examination types are done. For film-based image counts, the jackets were retrieved, and the number of grayscale and color images were counted. The number of images obtained per examination (for most examinations) in ultrasound increased with PACS use. This was more evident with some examination types (eg, pelvis). This result, however, has to be examined for possible systematic biases because ultrasound practice has changed over the time since the authors stopped using film routinely. The use of PACS in ultrasonography was not associated with an increase in the number of images per examination based solely on the use of PACS, with the exception of neonatal head studies. Increases in the number of images per study was otherwise associated with examinations for which changes in protocols resulted in the increased image counts.

  10. Reconstructing the CT number array from gray-level images and its application in PACS

    Science.gov (United States)

    Chen, Xu; Zhuang, Tian-ge; Wu, Wei

    2001-08-01

    Although DICOM compliant computed tomography has been prevailing in medical fields nowadays, there are some incompliant ones, from which we could hardly get the raw data and make an apropos interpretation due to the proprietary image format. Under such condition, one usually uses frame grabbers to capture CT images, the results of which could not be freely adjusted by radiologists as the original CT number array could. To alleviate the inflexibility, a new method is presented in this paper to reconstruct the array of CT number from several gray-level images acquired under different window settings. Its feasibility is investigated and a few tips are put forward to correct the errors caused respectively by 'Border Effect' and some hardware problems. The accuracy analysis proves it a good substitution for original CT number array acquisition. And this method has already been successfully used in our newly developing PACS and accepted by the radiologists in clinical use.

  11. Himage PACS: a new approach to storage, integration, and distribution of cardiologic images

    Science.gov (United States)

    Costa, Carlos M.; Silva, Augusto; Oliveira, Jose L.; Ribeiro, Vasco G.; Ribeiro, Jose

    2004-04-01

    This paper presents a Cardiology oriented information system that provides permanent availability of all clinical history, including alphanumeric and image data, with time and cost-effective transmission (reduced download time), without loss of image diagnosis quality and based on a Web Multimedia Integrated Access Interface. This implies the integration of HIS and PACS in a unique access interface, providing on-line and fast access to authorized healthcare professionals. The benefits obtained from the HIS-PACS integration and from the availability of all historical patient data are unquestionable to practitioners but also to the patients. Moreover, the system includes a telematic platform capable of establishing cooperative telemedicine sessions where our most impressive utilization is a transcontinental work platform for cardiovascular ultrasound. The key point of our approach starts with the construction of a DICOM private transfer syntax that is prepared to support any video encoder installed on a Windows-based station. With this structure it is possible to select the best encoder to a specific modality and work scenario. Good trade-off between compression ratio and diagnostic quality, low network traffic load, backup facilities and data portability are other achievements of this system.

  12. Automating PACS Quality Control with the Vanderbilt Image Processing Enterprise Resource.

    Science.gov (United States)

    Esparza, Michael L; Welch, E Brian; Landman, Bennett A

    2012-02-12

    Precise image acquisition is an integral part of modern patient care and medical imaging research. Periodic quality control using standardized protocols and phantoms ensures that scanners are operating according to specifications, yet such procedures do not ensure that individual datasets are free from corruption-for example due to patient motion, transient interference, or physiological variability. If unacceptable artifacts are noticed during scanning, a technologist can repeat a procedure. Yet, substantial delays may be incurred if a problematic scan is not noticed until a radiologist reads the scans or an automated algorithm fails. Given scores of slices in typical three-dimensional scans and wide-variety of potential use cases, a technologist cannot practically be expected inspect all images. In large-scale research, automated pipeline systems have had great success in achieving high throughput. However, clinical and institutional workflows are largely based on DICOM and PACS technologies; these systems are not readily compatible with research systems due to security and privacy restrictions. Hence, quantitative quality control has been relegated to individual investigators and too often neglected. Herein, we propose a scalable system, the Vanderbilt Image Processing Enterprise Resource-VIPER, to integrate modular quality control and image analysis routines with a standard PACS configuration. This server unifies image processing routines across an institutional level and provides a simple interface so that investigators can collaborate to deploy new analysis technologies. VIPER integrates with high performance computing environments has successfully analyzed all standard scans from our institutional research center over the course of the last 18 months.

  13. Dental PACS development in Korea

    International Nuclear Information System (INIS)

    Kim, Eun Kyung

    2008-01-01

    Picture archiving and communication system (PACS) is an image information technology system for the transmission and storage of medical images. In Korea the first full PACS was installed at Samsung Medical Center in 1994, but, the rate of distribution was very slow. The government's approval for the medical insurance reimbursement for full PACS examinations in November 1999 became the turning point. Thereafter the number of hospitals with full PACS has steeply increased. In September of this year, PACS was installed at 906 medical institutes, including most of university hospitals and general hospitals. The first full dental PACS was installed at Wonkwang University Dental Hospital in 2002. Now ten out of eleven university dental hospitals implemented full dental PACS. The current status and technological factors of dental PACS in Korean university dental hospitals and the future perspectives of dental PACS are described.

  14. Using polynomials to simplify fixed pattern noise and photometric correction of logarithmic CMOS image sensors.

    Science.gov (United States)

    Li, Jing; Mahmoodi, Alireza; Joseph, Dileepan

    2015-10-16

    An important class of complementary metal-oxide-semiconductor (CMOS) image sensors are those where pixel responses are monotonic nonlinear functions of light stimuli. This class includes various logarithmic architectures, which are easily capable of wide dynamic range imaging, at video rates, but which are vulnerable to image quality issues. To minimize fixed pattern noise (FPN) and maximize photometric accuracy, pixel responses must be calibrated and corrected due to mismatch and process variation during fabrication. Unlike literature approaches, which employ circuit-based models of varying complexity, this paper introduces a novel approach based on low-degree polynomials. Although each pixel may have a highly nonlinear response, an approximately-linear FPN calibration is possible by exploiting the monotonic nature of imaging. Moreover, FPN correction requires only arithmetic, and an optimal fixed-point implementation is readily derived, subject to a user-specified number of bits per pixel. Using a monotonic spline, involving cubic polynomials, photometric calibration is also possible without a circuit-based model, and fixed-point photometric correction requires only a look-up table. The approach is experimentally validated with a logarithmic CMOS image sensor and is compared to a leading approach from the literature. The novel approach proves effective and efficient.

  15. Determination of the size of an imaging data storage device at a full PACS hospital

    International Nuclear Information System (INIS)

    Cha, S. J.; Kim, Y. H.; Hur, G.

    2000-01-01

    To determine the appropriate size of a short and long-term storage device, bearing in mind the design factors involved and the installation costs. The number of radiologic studies quoted is the number of these undertaken during a one-year period at a university hospital with 650 beds, and reflects the actual number of each type of examination performed at a full PACS hospital. The average daily number of outpatients was 1586, while that of inpatients was 639.5. The numbers of radiologic studies performed were as follows : 378 among 189 outpatients, and 165 among 41 inpatients. The average daily number of examinations was 543, comprising 460 CR, 30 ultrasonograms, 25 CT, 8 MRI, 20 others. The total amount of digital images was 17.4 GB per day, while the amount of short-term data with lossless compression was 6.7 GB per day. During 14 days short-term storage, the amount of image data was 93.7 GB in disk array. The amount of data stored mid term (1 year), with lossy compression, was 369.1 GB. The amount of data stored in the form of long-term cache and educational images was 38.7 GB and 30 GB, respectively, The total size of disk array was 531.5 GB. A device suitable for the long-term storage of images, for at least five years, requires a capacity of 1845.5 GB. At a full PACS hospital with 600 beds, the minimum disk space required for the short-and mid-term storage of image data in disk array is 540 GB. The capacity required for long term storage (at least five years) is 1900 GB. (author)

  16. PACS on mobile devices

    Science.gov (United States)

    Parikh, Ashesh; Mehta, Nihal

    2015-03-01

    Recent advances in internet browser technologies makes it possible to incorporate advanced functionality of a traditional PACS for viewing DICOM medical images on standard web browsers without the need to pre-install any plug-ins, apps or software. We demonstrate some of the capabilities of standard web browsers setting the stage for a cloud-based PACS.

  17. Clinical evaluation of the JPEG2000 compression rate of CT and MR images for long term archiving in PACS

    International Nuclear Information System (INIS)

    Cha, Soon Joo; Kim, Sung Hwan; Kim, Yong Hoon

    2006-01-01

    We wanted to evaluate an acceptable compression rate of JPEG2000 for long term archiving of CT and MR images in PACS. Nine CT images and 9 MR images that had small or minimal lesions were randomly selected from the PACS at our institute. All the images are compressed with rates of 5:1, 10:1, 20:1, 40:1 and 80:1 by the JPEG2000 compression protocol. Pairs of original and compressed images were compared by 9 radiologists who were working independently. We designed a JPEG2000 viewing program for comparing two images on one monitor system for performing easy and quick evaluation. All the observers performed the comparison study twice on 5 mega pixel grey scale LCD monitors and 2 mega pixel color LCD monitors, respectively. The PSNR (Peak Signal to Noise Ratio) values were calculated for making quantitative comparisions. On MR and CT, all the images with 5:1 compression images showed no difference from the original images by all 9 observers and only one observer could detect a image difference on one CT image for 10:1 compression on only the 5 mega pixel monitor. For the 20:1 compression rate, clinically significant image deterioration was found in 50% of the images on the 5M pixel monitor study, and in 30% of the images on the 2M pixel monitor. PSNR values larger than 44 dB were calculated for all the compressed images. The clinically acceptable image compression rate for long term archiving by the JPEG2000 compression protocol is 10:1 for MR and CT, and if this is applied to PACS, it would reduce the cost and responsibility of the system

  18. An imaging-based photometric and colorimetric measurement method for characterizing OLED panels for lighting applications

    Science.gov (United States)

    Zhu, Yiting; Narendran, Nadarajah; Tan, Jianchuan; Mou, Xi

    2014-09-01

    The organic light-emitting diode (OLED) has demonstrated its novelty in displays and certain lighting applications. Similar to white light-emitting diode (LED) technology, it also holds the promise of saving energy. Even though the luminous efficacy values of OLED products have been steadily growing, their longevity is still not well understood. Furthermore, currently there is no industry standard for photometric and colorimetric testing, short and long term, of OLEDs. Each OLED manufacturer tests its OLED panels under different electrical and thermal conditions using different measurement methods. In this study, an imaging-based photometric and colorimetric measurement method for OLED panels was investigated. Unlike an LED that can be considered as a point source, the OLED is a large form area source. Therefore, for an area source to satisfy lighting application needs, it is important that it maintains uniform light level and color properties across the emitting surface of the panel over a long period. This study intended to develop a measurement procedure that can be used to test long-term photometric and colorimetric properties of OLED panels. The objective was to better understand how test parameters such as drive current or luminance and temperature affect the degradation rate. In addition, this study investigated whether data interpolation could allow for determination of degradation and lifetime, L70, at application conditions based on the degradation rates measured at different operating conditions.

  19. The future of PACS

    International Nuclear Information System (INIS)

    Nagy, Paul G.

    2007-01-01

    How will the future of picture archiving and communication systems (PACS) look, and how will this future affect the practice of radiology? We are currently experiencing disruptive innovations that will force an architectural redesign, making the majority of today’s commercial PACS obsolete as the field matures and expands to include imaging throughout the medical enterprise. The common architecture used for PACS cannot handle the massive amounts of data being generated by even current versions of computed tomography and magnetic resonance scanners. If a PACS cannot handle today’s technology, what will happen as the field expands to encompass pathology imaging, cone-beam reconstruction, and multispectral imaging? The ability of these new technologies to enhance research and clinical care will be impaired if PACS architectures are not prepared to support them. In attempting a structured approach to predictions about the future of PACS, we offer projections about the technologies underlying PACS as well as the evolution of standards development and the changing needs of a broad range of medical imaging. Simplified models of the history of the PACS industry are mined for the assumptions they provide about future innovations and trends. The physicist frequently participates in or directs technical assessments for medical equipment, and many physicists have extended these activities to include imaging informatics. It is hoped that by applying these speculative but experienced-based predictions, the interested medical physicist will be better able to take the lead in setting information technology strategies that will help facilities not only prepare for the future but continue to enjoy the benefits of technological innovations without disruptive, expensive, and unexpected changes in architecture. A good PACS strategy can help accelerate the time required for innovations to go from the drawing board to clinical implementation.

  20. Correcting geometric and photometric distortion of document images on a smartphone

    Science.gov (United States)

    Simon, Christian; Williem; Park, In Kyu

    2015-01-01

    A set of document image processing algorithms for improving the optical character recognition (OCR) capability of smartphone applications is presented. The scope of the problem covers the geometric and photometric distortion correction of document images. The proposed framework was developed to satisfy industrial requirements. It is implemented on an off-the-shelf smartphone with limited resources in terms of speed and memory. Geometric distortions, i.e., skew and perspective distortion, are corrected by sending horizontal and vertical vanishing points toward infinity in a downsampled image. Photometric distortion includes image degradation from moiré pattern noise and specular highlights. Moiré pattern noise is removed using low-pass filters with different sizes independently applied to the background and text region. The contrast of the text in a specular highlighted area is enhanced by locally enlarging the intensity difference between the background and text while the noise is suppressed. Intensive experiments indicate that the proposed methods show a consistent and robust performance on a smartphone with a runtime of less than 1 s.

  1. Inferring the photometric and size evolution of galaxies from image simulations. I. Method

    Science.gov (United States)

    Carassou, Sébastien; de Lapparent, Valérie; Bertin, Emmanuel; Le Borgne, Damien

    2017-09-01

    Context. Current constraints on models of galaxy evolution rely on morphometric catalogs extracted from multi-band photometric surveys. However, these catalogs are altered by selection effects that are difficult to model, that correlate in non trivial ways, and that can lead to contradictory predictions if not taken into account carefully. Aims: To address this issue, we have developed a new approach combining parametric Bayesian indirect likelihood (pBIL) techniques and empirical modeling with realistic image simulations that reproduce a large fraction of these selection effects. This allows us to perform a direct comparison between observed and simulated images and to infer robust constraints on model parameters. Methods: We use a semi-empirical forward model to generate a distribution of mock galaxies from a set of physical parameters. These galaxies are passed through an image simulator reproducing the instrumental characteristics of any survey and are then extracted in the same way as the observed data. The discrepancy between the simulated and observed data is quantified, and minimized with a custom sampling process based on adaptive Markov chain Monte Carlo methods. Results: Using synthetic data matching most of the properties of a Canada-France-Hawaii Telescope Legacy Survey Deep field, we demonstrate the robustness and internal consistency of our approach by inferring the parameters governing the size and luminosity functions and their evolutions for different realistic populations of galaxies. We also compare the results of our approach with those obtained from the classical spectral energy distribution fitting and photometric redshift approach. Conclusions: Our pipeline infers efficiently the luminosity and size distribution and evolution parameters with a very limited number of observables (three photometric bands). When compared to SED fitting based on the same set of observables, our method yields results that are more accurate and free from

  2. Second-generation PACS

    International Nuclear Information System (INIS)

    Mattheus, R.; Osteaux, M.; Spruiyt, D.

    1989-01-01

    Purpose: In recent years, a gradual shift toward digital techniques has occurred in the field of medical imaging. The authors discuss how, with their approach, digital image management can be used in daily clinical routine. Instead of a centralized approach, we have taken a decentralized, multivendor, phase-expandable approach. The IMAC (image management and communication) architecture is a reflection of the organization of the imaging department. A section defined for each group of examinations (CT, MR imaging, DSA, emergency), has its own (dedicated) PACS environment, connected to the total PACS. Network management for controlling the image flow is based on patient appointments, scheduling of rooms, and work

  3. PACS: Concepts and Trends

    Science.gov (United States)

    Bandon, David; Ratib, Osman; Lovis, Christian; Geissbuhler, Antoine

    Picture Archiving and Communication Systems (PACS) are becoming part of the core components of today's infrastructure for digital radiology. In modern setting they also extend to the whole medical enterprise and integrate into the patient medical record. While local architectures may vary significantly, the major features such as image archiving and retrieval, workflow management, workstations and image acquisition and quality control systems constitute the key elements of such systems. PACS has also vocation to extend beyond the radiological images to become the common platform for hospital wide management of all images. The wireless access can contribute to expand the scope of image distribution.

  4. Photometrics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Photometrics Laboratory provides the capability to measure, analyze and characterize radiometric and photometric properties of light sources and filters,...

  5. [Validation of the Physical Appearance Comparison Scale (PACS) in a German Sample: Psychometric Properties and Association with Eating Behavior, Body Image and Self-Esteem].

    Science.gov (United States)

    Claire Mölbert, Simone; Hautzinger, Martin; Karnath, Hans-Otto; Zipfel, Stephan; Giel, Katrin

    2017-02-01

    The Physical Appearance Comparison Scale (PACS [14]) is the most commonly used validated measure of body-related social comparison habits. Here we investigate reliability and construct validity of the PACS in a German sample. Participants (n=75 men, n=75 women and n=25 women with a confirmed diagnosis of anorexia nervosa) completed the PACS along with measures of eating disorder pathology, body image and self-esteem. Results show an adequate internal consistency of the PACS for the female subgroups and medium to high correlations with eating disorder pathology, body image and self-esteem. PACS total score differed significantly between groups, with men scoring lowest and women with anorexia nervosa scoring highest. We conclude that the PACS is a sufficiently reliable and valid measure of body-related social comparison habits in women. In men, it should only be used with special care. The PACS is generally suitable to promote patient studies testing the role of social comparisons for the patho-mechanisms of eating disorders. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Photometric Calibration and Image Stitching for a Large Field of View Multi-Camera System

    Directory of Open Access Journals (Sweden)

    Yu Lu

    2016-04-01

    Full Text Available A new compact large field of view (FOV multi-camera system is introduced. The camera is based on seven tiny complementary metal-oxide-semiconductor sensor modules covering over 160° × 160° FOV. Although image stitching has been studied extensively, sensor and lens differences have not been considered in previous multi-camera devices. In this study, we have calibrated the photometric characteristics of the multi-camera device. Lenses were not mounted on the sensor in the process of radiometric response calibration to eliminate the influence of the focusing effect of uniform light from an integrating sphere. Linearity range of the radiometric response, non-linearity response characteristics, sensitivity, and dark current of the camera response function are presented. The R, G, and B channels have different responses for the same illuminance. Vignetting artifact patterns have been tested. The actual luminance of the object is retrieved by sensor calibration results, and is used to blend images to make panoramas reflect the objective luminance more objectively. This compensates for the limitation of stitching images that are more realistic only through the smoothing method. The dynamic range limitation of can be resolved by using multiple cameras that cover a large field of view instead of a single image sensor with a wide-angle lens. The dynamic range is expanded by 48-fold in this system. We can obtain seven images in one shot with this multi-camera system, at 13 frames per second.

  7. An Improved Photometric Calibration of the Sloan Digital SkySurvey Imaging Data

    Energy Technology Data Exchange (ETDEWEB)

    Padmanabhan, Nikhil; Schlegel, David J.; Finkbeiner, Douglas P.; Barentine, J.C.; Blanton, Michael R.; Brewington, Howard J.; Gunn, JamesE.; Harvanek, Michael; Hogg, David W.; Ivezic, Zeljko; Johnston, David; Kent, Stephen M.; Kleinman, S.J.; Knapp, Gillian R.; Krzesinski, Jurek; Long, Dan; Neilsen Jr., Eric H.; Nitta, Atsuko; Loomis, Craig; Lupton,Robert H.; Roweis, Sam; Snedden, Stephanie A.; Strauss, Michael A.; Tucker, Douglas L.

    2007-09-30

    We present an algorithm to photometrically calibrate widefield optical imaging surveys, that simultaneously solves for thecalibration parameters and relative stellar fluxes using overlappingobservations. The algorithm decouples the problem of "relative"calibrations from that of "absolute" calibrations; the absolutecalibration is reduced to determining a few numbers for the entiresurvey. We pay special attention to the spatial structure of thecalibration errors, allowing one to isolate particular error modes indownstream analyses. Applying this to the SloanDigital Sky Survey imagingdata, we achieve ~;1 percent relative calibration errors across 8500sq.deg/ in griz; the errors are ~;2 percent for the u band. These errorsare dominated by unmodelled atmospheric variations at Apache PointObservatory. These calibrations, dubbed ubercalibration, are now publicwith SDSS Data Release 6, and will be a part of subsequent SDSS datareleases.

  8. The Preflight Photometric Calibration of the Extreme-Ultraviolet Imaging Telescope EIT

    Science.gov (United States)

    Dere, K. P.; Moses, J. D.; Delaboudiniere, J. -P.; Brunaud, J.; Carabetian, C.; Hochedez, J. -F.; Song, X. Y.; Catura, R. C.; Clette, F.; Defise, J. -M.

    2000-01-01

    This paper presents the preflight photometric calibration of the Extreme-ultraviolet Imaging Telescope (EIT) aboard the Solar and Heliospheric Observatory (SOHO). The EIT consists of a Ritchey-Chretien telescope with multilayer coatings applied to four quadrants of the primary and secondary mirrors, several filters and a backside-thinned CCD detector. The quadrants of the EIT optics were used to observe the Sun in 4 wavelength bands that peak near 171, 195, 284, and 304 . Before the launch of SOHO, the EIT mirror reflectivities, the filter transmissivities and the CCD quantum efficiency were measured and these values are described here. The instrumental throughput in terms of an effective area is presented for each of the various mirror quadrant and filter wheel combinations. The response to a coronal plasma as a function of temperature is also determined and the expected count rates are compared to the count rates observed in a coronal hole, the quiet Sun and an active region.

  9. PHOTOMETRIC REDSHIFTS OF SUBMILLIMETER GALAXIES

    International Nuclear Information System (INIS)

    Chakrabarti, Sukanya; Magnelli, Benjamin; Lutz, Dieter; Berta, Stefano; Popesso, Paola; McKee, Christopher F.; Pozzi, Francesca

    2013-01-01

    We use the photometric redshift method of Chakrabarti and McKee to infer photometric redshifts of submillimeter galaxies with far-IR (FIR) Herschel data obtained as part of the PACS Evolutionary Probe program. For the sample with spectroscopic redshifts, we demonstrate the validity of this method over a large range of redshifts (4 ∼> z ∼> 0.3) and luminosities, finding an average accuracy in (1 + z phot )/(1 + z spec ) of 10%. Thus, this method is more accurate than other FIR photometric redshift methods. This method is different from typical FIR photometric methods in deriving redshifts from the light-to-gas mass (L/M) ratio of infrared-bright galaxies inferred from the FIR spectral energy distribution, rather than dust temperatures. To assess the dependence of our photometric redshift method on the data in this sample, we contrast the average accuracy of our method when we use PACS data, versus SPIRE data, versus both PACS and SPIRE data. We also discuss potential selection effects that may affect the Herschel sample. Once the redshift is derived, we can determine physical properties of infrared-bright galaxies, including the temperature variation within the dust envelope, luminosity, mass, and surface density. We use data from the GOODS-S field to calculate the star formation rate density (SFRD) of submillimeter bright sources detected by AzTEC and PACS. The AzTEC-PACS sources, which have a threshold 850 μm flux ∼> 5 mJy, contribute 15% of the SFRD from all ultraluminous infrared galaxies (L IR ∼> 10 12 L ☉ ), and 3% of the total SFRD at z ∼ 2

  10. Near Real-Time Photometric Data Processing for the Solar Mass Ejection Imager (SMEI)

    Science.gov (United States)

    Hick, P. P.; Buffington, A.; Jackson, B. V.

    2004-12-01

    The Solar Mass Ejection Imager (SMEI) records a photometric white-light response of the interplanetary medium from Earth over most of the sky in near real time. In the first two years of operation the instrument has recorded the inner heliospheric response to several hundred CMEs, including the May 28, 2003 and the October 28, 2003 halo CMEs. In this preliminary work we present the techniques required to process the SMEI data from the time the raw CCD images become available to their final assembly in photometrically accurate maps of the sky brightness relative to a long-term time base. Processing of the SMEI data includes integration of new data into the SMEI data base; a conditioning program that removes from the raw CCD images an electronic offset ("pedestal") and a temperature-dependent dark current pattern; an "indexing" program that places these CCD images onto a high-resolution sidereal grid using known spacecraft pointing information. At this "indexing" stage further conditioning removes the bulk of the the effects of high-energy-particle hits ("cosmic rays"), space debris inside the field of view, and pixels with a sudden state change ("flipper pixels"). Once the high-resolution grid is produced, it is reformatted to a lower-resolution set of sidereal maps of sky brightness. From these sidereal maps we remove bright stars, background stars, and a zodiacal cloud model (their brightnesses are retained as additional data products). The final maps can be represented in any convenient sky coordinate system. Common formats are Sun-centered Hammer-Aitoff or "fisheye" maps. Time series at selected locations on these maps are extracted and processed further to remove aurorae, variable stars and other unwanted signals. These time series (with a long-term base removed) are used in 3D tomographic reconstructions. The data processing is distributed over multiple PCs running Linux, and, runs as much as possible automatically using recurring batch jobs ('cronjobs'). The

  11. Photometric parameter maps of the Moon derived from LROC WAC images

    Science.gov (United States)

    Sato, H.; Robinson, M. S.; Hapke, B. W.; Denevi, B. W.; Boyd, A. K.

    2013-12-01

    Spatially resolved photometric parameter maps were computed from 21 months of Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) images. Due to a 60° field-of-view (FOV), the WAC achieves nearly global coverage of the Moon each month with more than 50% overlap from orbit-to-orbit. From the repeat observations at various viewing and illumination geometries, we calculated Hapke bidirectional reflectance model parameters [1] for 1°x1° "tiles" from 70°N to 70°S and 0°E to 360°E. About 66,000 WAC images acquired from February 2010 to October 2011 were converted from DN to radiance factor (I/F) though radiometric calibration, partitioned into gridded tiles, and stacked in a time series (tile-by-tile method [2]). Lighting geometries (phase, incidence, emission) were computed using the WAC digital terrain model (100 m/pixel) [3]. The Hapke parameters were obtained by model fitting against I/F within each tile. Among the 9 parameters of the Hapke model, we calculated 3 free parameters (w, b, and hs) by setting constant values for 4 parameters (Bco=0, hc=1, θ, φ=0) and interpolating 2 parameters (c, Bso). In this simplification, we ignored the Coherent Backscatter Opposition Effect (CBOE) to avoid competing CBOE and Shadow Hiding Opposition Effect (SHOE). We also assumed that surface regolith porosity is uniform across the Moon. The roughness parameter (θ) was set to an averaged value from the equator (× 3°N). The Henyey-Greenstein double lobe function (H-G2) parameter (c) was given by the 'hockey stick' relation [4] (negative correlation) between b and c based on laboratory measurements. The amplitude of SHOE (Bso) was given by the correlation between w and Bso at the equator (× 3°N). Single scattering albedo (w) is strongly correlated to the photometrically normalized I/F, as expected. The c shows an inverse trend relative to b due to the 'hockey stick' relation. The parameter c is typically low for the maria (0.08×0.06) relative to the

  12. Picture archiving and communication systems (PACS) for hospitals, a survey

    International Nuclear Information System (INIS)

    Haar Romeny, B.M. ter; Graaf, C.N. de; Waes, P.F.G.M. van; Rijk, P.P. van; Helder, J.C.; Valk, J.P.J. de

    1985-01-01

    In this article a survey is given for Picture Archiving and Communication Systems (PACS). Several aspects of PACS are treated, as image management, the introduction of the system, expenses etc. Special reference is made to the component parts of PACS: image stations, memory, network, software and coupling to the hospital information system. The introduction of PACS in Dutch hospitals is described. (Auth.)

  13. Three-Dimensional Reconstruction from Single Image Base on Combination of CNN and Multi-Spectral Photometric Stereo

    Directory of Open Access Journals (Sweden)

    Liang Lu

    2018-03-01

    Full Text Available Multi-spectral photometric stereo can recover pixel-wise surface normal from a single RGB image. The difficulty lies in that the intensity in each channel is the tangle of illumination, albedo and camera response; thus, an initial estimate of the normal is required in optimization-based solutions. In this paper, we propose to make a rough depth estimation using the deep convolutional neural network (CNN instead of using depth sensors or binocular stereo devices. Since high-resolution ground-truth data is expensive to obtain, we designed a network and trained it with rendered images of synthetic 3D objects. We use the model to predict initial normal of real-world objects and iteratively optimize the fine-scale geometry in the multi-spectral photometric stereo framework. The experimental results illustrate the improvement of the proposed method compared with existing methods.

  14. Three-Dimensional Reconstruction from Single Image Base on Combination of CNN and Multi-Spectral Photometric Stereo

    Science.gov (United States)

    Lu, Liang; Qi, Lin; Luo, Yisong; Jiao, Hengchao; Dong, Junyu

    2018-01-01

    Multi-spectral photometric stereo can recover pixel-wise surface normal from a single RGB image. The difficulty lies in that the intensity in each channel is the tangle of illumination, albedo and camera response; thus, an initial estimate of the normal is required in optimization-based solutions. In this paper, we propose to make a rough depth estimation using the deep convolutional neural network (CNN) instead of using depth sensors or binocular stereo devices. Since high-resolution ground-truth data is expensive to obtain, we designed a network and trained it with rendered images of synthetic 3D objects. We use the model to predict initial normal of real-world objects and iteratively optimize the fine-scale geometry in the multi-spectral photometric stereo framework. The experimental results illustrate the improvement of the proposed method compared with existing methods. PMID:29498703

  15. dicomPACS: PACS Leader in Germany - Kodak Partner

    OpenAIRE

    Maziyar Shakeri

    2007-01-01

    History of Distributor: We are PDP Co. (Pardazesh Danesh Pezeshki) founded in 1998 with more than 8 years Experiments in Diagnostic Medical Imaging Market .we launched our New Division in 2002 for Digital Imaging and Softcopy under name of PDP View . We studied our market demands and PACS Provider Companies for 2 years and finally we signed the Contract with the first leader German PACS Provider named dicomPACS ® ."nWe are the only company who their 3 engineers well trained in th...

  16. Evaluation of radiological workstations and web-browser-based image distribution clients for a PACS project in hands-on workshops

    International Nuclear Information System (INIS)

    Boehm, Thomas; Handgraetinger, Oliver; Voellmy, Daniel R.; Marincek, Borut; Wildermuth, Simon; Link, Juergen; Ploner, Ricardo

    2004-01-01

    The methodology and outcome of a hands-on workshop for the evaluation of PACS (picture archiving and communication system) software for a multihospital PACS project are described. The following radiological workstations and web-browser-based image distribution software clients were evaluated as part of a multistep evaluation of PACS vendors in March 2001: Impax DS 3000 V 4.1/Impax Web1000 (Agfa-Gevaert, Mortsel, Belgium); PathSpeed V 8.0/PathSpeed Web (GE Medical Systems, Milwaukee, Wis., USA); ID Report/ID Web (Image Devices, Idstein, Germany); EasyVision DX/EasyWeb (Philips Medical Systems, Eindhoven, Netherlands); and MagicView 1000 VB33a/MagicWeb (Siemens Medical Systems, Erlangen, Germany). A set of anonymized DICOM test data was provided to enable direct image comparison. Radiologists (n=44) evaluated the radiological workstations and nonradiologists (n=53) evaluated the image distribution software clients using different questionnaires. One vendor was not able to import the provided DICOM data set. Another vendor had problems in displaying imported cross-sectional studies in the correct stack order. Three vendors (Agfa-Gevaert, GE, Philips) presented server-client solutions with web access. Two (Siemens, Image Devices) presented stand-alone solutions. The highest scores in the class of radiological workstations were achieved by ID Report from Image Devices (p<0.005). In the class of image distribution clients, the differences were statistically not significant. Questionnaire-based evaluation was shown to be useful for guaranteeing systematic assessment. The workshop was a great success in raising interest in the PACS project in a large group of future clinical users. The methodology used in the present study may be useful for other hospitals evaluating PACS. (orig.)

  17. Photometric redshift estimation via deep learning. Generalized and pre-classification-less, image based, fully probabilistic redshifts

    Science.gov (United States)

    D'Isanto, A.; Polsterer, K. L.

    2018-01-01

    Context. The need to analyze the available large synoptic multi-band surveys drives the development of new data-analysis methods. Photometric redshift estimation is one field of application where such new methods improved the results, substantially. Up to now, the vast majority of applied redshift estimation methods have utilized photometric features. Aims: We aim to develop a method to derive probabilistic photometric redshift directly from multi-band imaging data, rendering pre-classification of objects and feature extraction obsolete. Methods: A modified version of a deep convolutional network was combined with a mixture density network. The estimates are expressed as Gaussian mixture models representing the probability density functions (PDFs) in the redshift space. In addition to the traditional scores, the continuous ranked probability score (CRPS) and the probability integral transform (PIT) were applied as performance criteria. We have adopted a feature based random forest and a plain mixture density network to compare performances on experiments with data from SDSS (DR9). Results: We show that the proposed method is able to predict redshift PDFs independently from the type of source, for example galaxies, quasars or stars. Thereby the prediction performance is better than both presented reference methods and is comparable to results from the literature. Conclusions: The presented method is extremely general and allows us to solve of any kind of probabilistic regression problems based on imaging data, for example estimating metallicity or star formation rate of galaxies. This kind of methodology is tremendously important for the next generation of surveys.

  18. Sizing a PACS

    Science.gov (United States)

    Wilson, Dennis L.; Glicksman, Robert A.

    1994-05-01

    A Picture Archiving and Communications System (PACS) must be able to support the image rate of the medical treatment facility. In addition the PACS must have adequate working storage and archive storage capacity required. The calculation of the number of images per minute and the capacity of working storage and of archiving storage is discussed. The calculation takes into account the distribution of images over the different size of radiological images, the distribution between inpatient and outpatient, and the distribution over plain film CR images and other modality images. The support of the indirect clinical image load is difficult to estimate and is considered in some detail. The result of the exercise for a particular hospital is an estimate of the average size of the images and exams on the system, of the number of gigabytes of working storage, of the number of images moved per minute, of the size of the archive in gigabytes, and of the number of images that are to be moved by the archive per minute. The types of storage required to support the image rates and the capacity required are discussed.

  19. Comparing image search behaviour in the ARRS GoldMiner search engine and a clinical PACS/RIS.

    Science.gov (United States)

    De-Arteaga, Maria; Eggel, Ivan; Do, Bao; Rubin, Daniel; Kahn, Charles E; Müller, Henning

    2015-08-01

    Information search has changed the way we manage knowledge and the ubiquity of information access has made search a frequent activity, whether via Internet search engines or increasingly via mobile devices. Medical information search is in this respect no different and much research has been devoted to analyzing the way in which physicians aim to access information. Medical image search is a much smaller domain but has gained much attention as it has different characteristics than search for text documents. While web search log files have been analysed many times to better understand user behaviour, the log files of hospital internal systems for search in a PACS/RIS (Picture Archival and Communication System, Radiology Information System) have rarely been analysed. Such a comparison between a hospital PACS/RIS search and a web system for searching images of the biomedical literature is the goal of this paper. Objectives are to identify similarities and differences in search behaviour of the two systems, which could then be used to optimize existing systems and build new search engines. Log files of the ARRS GoldMiner medical image search engine (freely accessible on the Internet) containing 222,005 queries, and log files of Stanford's internal PACS/RIS search called radTF containing 18,068 queries were analysed. Each query was preprocessed and all query terms were mapped to the RadLex (Radiology Lexicon) terminology, a comprehensive lexicon of radiology terms created and maintained by the Radiological Society of North America, so the semantic content in the queries and the links between terms could be analysed, and synonyms for the same concept could be detected. RadLex was mainly created for the use in radiology reports, to aid structured reporting and the preparation of educational material (Lanlotz, 2006) [1]. In standard medical vocabularies such as MeSH (Medical Subject Headings) and UMLS (Unified Medical Language System) specific terms of radiology are often

  20. PACS industry in Korea

    Science.gov (United States)

    Kim, Hee-Joung

    2002-05-01

    PACS industry in Korea has been rapidly growing, since government had supported collaborative PACS project between industry and university hospital. In the beginning, PACS industry had focused on developing peripheral PACS solutions, while the Korea PACS society was being formed. A few companies had started developing and installing domestic large-scale full-PACS system for teaching hospitals. Several years later, many hospitals have installed full-PACS system with national policy of reimbursement for PACS exams in November 1999. Both experiences of full-PACS installation and national policy generated tremendous intellectual and technological expertise about PACS at all levels, clinical, hospital management, education, and industrial sectors. There are now more than 20 domestic PACS companies. They have enough experiences which are capable of installing a truly full-PACS system for large-scale teaching hospitals. As an example, a domestic company had installed more than 40 full-PACS systems within 2-3 years. Enough experiences of full-PACS installation in Korea lead PACS industry to start exporting their full-PACS solutions. However, further understanding and timely implementation of continuously evolving international standard and integrated healthcare enterprise concepts may be necessary for international leading of PACS technologies for the future.

  1. Picture archiving and communications systems (PACS)

    International Nuclear Information System (INIS)

    Huang, H.K.; Dwyer, S.J. III; Angus, W.M.; Capp, M.P.; Arenson, R.L.; Kangarloo, H.

    1987-01-01

    This special focus session discusses the current status of picture archiving and communication systems (PACS). The first presentation focuses on the technological advances in various PACS components. The second presentation concentrates on image archiving - what is required, what is available. The third talk is on the concept of a total digital radiology department in the past, the present, and the future. The fourth panelist discusses evaluating various imaging systems as PACS components for the intensive care unit. Finally, one hears about clinical experience with two operating PACS modules, one in pediatric radiology and the second in a coronary care unit

  2. Integrated RIS-PACS system

    International Nuclear Information System (INIS)

    Nishihara, Eitaro; Kura, Hiroyuki; Fukushima, Yuki

    1994-01-01

    We have developed an integrated RIS-PACS (radiology information system-picture archiving and communication system) system which supports examination, interpretation, and management in the diagnostic imaging department. The system was introduced in the Toshiba Hospital in May 1993, concurrently with the renewal of the hospital facilities. The integrated RIS-PACS system consists of a radiology information management system, and an image management system. The system supports wet (immediate) reading and chronological comparative reading using viewing workstation, enables routine operations to be performed in the diagnostic imaging department without film transportation, and contributes to the improvement of management efficiency in the department. (author)

  3. Vendor neutral archive in PACS

    International Nuclear Information System (INIS)

    Agarwal, Tapesh Kumar; Sanjeev

    2012-01-01

    An archive is a location containing a collection of records, documents, or other materials of historical importance. An integral part of Picture Archiving and Communication System (PACS) is archiving. When a hospital needs to migrate a PACS vendor, the complete earlier data need to be migrated in the format of the newly procured PACS. It is both time and money consuming. To address this issue, the new concept of vendor neutral archive (VNA) has emerged. A VNA simply decouples the PACS and workstations at the archival layer. This is achieved by developing an application engine that receives, integrates, and transmits the data using the different syntax of a Digital Imaging and Communication in Medicine (DICOM) format. Transferring the data belonging to the old PACS to a new one is performed by a process called migration of data. In VNA, a number of different data migration techniques are available to facilitate transfer from the old PACS to the new one, the choice depending on the speed of migration and the importance of data. The techniques include simple DICOM migration, prefetch-based DICOM migration, medium migration, and the expensive non-DICOM migration. “Vendor neutral” may not be a suitable term, and “architecture neutral,” “PACS neutral,” “content neutral,” or “third-party neutral” are probably better and preferred terms. Notwithstanding this, the VNA acronym has come to stay in both the medical IT user terminology and in vendor nomenclature, and radiologists need to be aware of its impact in PACS across the globe

  4. Integration of XNAT/PACS, DICOM, and research software for automated multi-modal image analysis

    Science.gov (United States)

    Gao, Yurui; Burns, Scott S.; Lauzon, Carolyn B.; Fong, Andrew E.; James, Terry A.; Lubar, Joel F.; Thatcher, Robert W.; Twillie, David A.; Wirt, Michael D.; Zola, Marc A.; Logan, Bret W.; Anderson, Adam W.; Landman, Bennett A.

    2013-03-01

    Traumatic brain injury (TBI) is an increasingly important public health concern. While there are several promising avenues of intervention, clinical assessments are relatively coarse and comparative quantitative analysis is an emerging field. Imaging data provide potentially useful information for evaluating TBI across functional, structural, and microstructural phenotypes. Integration and management of disparate data types are major obstacles. In a multi-institution collaboration, we are collecting electroencephalogy (EEG), structural MRI, diffusion tensor MRI (DTI), and single photon emission computed tomography (SPECT) from a large cohort of US Army service members exposed to mild or moderate TBI who are undergoing experimental treatment. We have constructed a robust informatics backbone for this project centered on the DICOM standard and eXtensible Neuroimaging Archive Toolkit (XNAT) server. Herein, we discuss (1) optimization of data transmission, validation and storage, (2) quality assurance and workflow management, and (3) integration of high performance computing with research software.

  5. Quantitative surface topography assessment of directly compressed and roller compacted tablet cores using photometric stereo image analysis

    DEFF Research Database (Denmark)

    Allesø, Morten; Carstensen, Jens Michael; Holm, Per

    2016-01-01

    Surface topography, in the context of surface smoothness/roughness, was investigated by the use of an image analysis technique, MultiRay™, related to photometric stereo, on different tablet batches manufactured either by direct compression or roller compaction. In the present study, oblique...... illumination of the tablet (darkfield) was considered and the area of cracks and pores in the surface was used as a measure of tablet surface topography; the higher a value, the rougher the surface. The investigations demonstrated a high precision of the proposed technique, which was able to rapidly (within...... milliseconds) and quantitatively measure the obtained surface topography of the produced tablets. Compaction history, in the form of applied roll force and tablet punch pressure, was also reflected in the measured smoothness of the tablet surfaces. Generally it was found that a higher degree of plastic...

  6. PACS in the nuclear medicine service

    International Nuclear Information System (INIS)

    Bitter, F.; Hellwig, D.; Weller, R.; Almasi, L.; Adam, W.E.

    1988-01-01

    A Picture Archiving and Communication System (PACS) is to be understood as a central system in a hospital spanning all services, interconnecting all imaging stations and allowing digital picture archivation. All data of a patient are prepared for direct access. A PAC system is made up of the following components: imaging equipment and data systems, viewing stations (image display), picture communication, storage, archive, connection to hospital information system. The authors explain the requirements to be met by a PACS, its set-up and mode of function, and they system the use. (orig./MG) [de

  7. Picture archiving and communications systems (PACS): an introduction

    International Nuclear Information System (INIS)

    Schwartz, L.H.

    2001-01-01

    Picture Archiving and Communications Systems (PACS) has revolutionized the practice of radiology. PACS consist of a variety of electronic/computer components, and the connectivity between these components. PACS is an efficient means to transmit, store, retrieve and digitally display medical images

  8. PACS/IMAC technology assessment

    OpenAIRE

    Schilling, Ronald B.

    1997-01-01

    According to Peter Ogle of Digital Imaging (San Francisco, CA), “Radiologists should help identify common values for the use of information technology in medicine.” Achieving a set of common values often requires a framework for organizing the thought process involved. That is the focus of this article in addressing the subject of picture archiving and communication system (PACS) technology assessment.

  9. Urological diagnosis using clinical PACS

    Science.gov (United States)

    Mills, Stephen F.; Spetz, Kevin S.; Dwyer, Samuel J., III

    1995-05-01

    Urological diagnosis using fluoroscopy images has traditionally been performed using radiographic films. Images are generally acquired in conjunction with the application of a contrast agent, processed to create analog films, and inspected to ensure satisfactory image quality prior to being provided to a radiologist for reading. In the case of errors the entire process must be repeated. In addition, the radiologist must then often go to a particular reading room, possibly in a remote part of the healthcare facility, to read the images. The integration of digital fluoroscopy modalities with clinical PACS has the potential to significantly improve the urological diagnosis process by providing high-speed access to images at a variety of locations within a healthcare facility without costly film processing. The PACS additionally provides a cost-effective and reliable means of long-term storage and allows several medical users to simultaneously view the same images at different locations. The installation of a digital data interface between the existing clinically operational PACS at the University of Virginia Health Sciences Center and a digital urology fluoroscope is described. Preliminary user interviews that have been conducted to determine the clinical effectiveness of PACS workstations for urological diagnosis are discussed. The specific suitability of the workstation medium is discussed, as are overall advantages and disadvantages of the hardcopy and softcopy media in terms of efficiency, timeliness and cost. Throughput metrics and some specific parameters of gray-scale viewing stations and the expected system impacts resulting from the integration of a urology fluoroscope with PACS are also discussed.

  10. Evaluation of a PACS workstation for interpreting body CT studies

    International Nuclear Information System (INIS)

    Franken, E.A.; Berbaum, K.S.; Honda, H.; McGuire, C.; Weis, R.R.; Barloon, T.

    1989-01-01

    This paper reports conventional hard-copy images from 266 body CT studies compared with those provided by a picture archiving and communication system (PACS) workstation. PACS images were evaluated before and after use of various image processing features. Most cases were depicted equally well, but in about one-fourth of the cases, diagnostic features were shown more clearly on PACS images. When PACS images were viewed first, a change in diagnosis after subsequent hardcopy inspection was infrequent, but when hard-copy images were viewed first, the results were converse. The image processing features of PACS were critical for its superior performance. The ability of a PACS to provide both image display and manipulation results in the superiority of that system

  11. A PACS maturity model: a systematic meta-analytic review on maturation and evolvability of PACS in the hospital enterprise.

    NARCIS (Netherlands)

    Wetering, R. van de; Batenburg, R.

    2009-01-01

    INTRODUCTION: With PACS and medical imaging technology maturing, the importance of organizational maturity and effective deployment of PACS in the hospital enterprise are becoming significant. OBJECTIVE: The objective of this paper is twofold. Firstly, PACS literature on maturity and evolvability in

  12. Photometric and Colorimeric Comparison of HDR and Spctrally Resolved Rendering Images

    DEFF Research Database (Denmark)

    Amdemeskel, Mekbib Wubishet; Soreze, Thierry Silvio Claude; Thorseth, Anders

    2017-01-01

    In this paper, we will demonstrate a comparison between measured colorimetric images, and simulated images from a physics based rendering engine. The colorimetric images are high dynamic range (HDR) and taken with a luminance and colour camera mounted on a goniometer. For the comparison, we have ...

  13. Short history of PACS. Part I: USA

    International Nuclear Information System (INIS)

    Huang, H.K.

    2011-01-01

    This historical review covers the PACS development in the USA during the past 28 years from 1982 to 2010. General historical remarks of PACS and international scene in three stages from infancy, puberty to adolescence are presented. Early PACS development was mostly financed by the federal government including the National Institutes of Health (NIH) and the U.S. Army Medical Research and Materiel Command. PACS evolution went through several stages. The earliest stages included the definition of large-scale PACS, establishment of the DICOM and other standards, the development of some early key PACS related technologies, and PACS implementation strategies. The later stages were in the concept of enterprise PACS, IHE (Integrating the Healthcare Enterprise) workflow profiles, and ePR with image distribution. The current most excited accomplishment is in the development of the new field in medical imaging informatics. This review goes through these stages and events in the USA during these 28 years, whenever an event involved participants from other countries, the contributors are cited.

  14. Short history of PACS. Part I: USA.

    Science.gov (United States)

    Huang, H K

    2011-05-01

    This historical review covers the PACS development in the USA during the past 28 years from 1982 to 2010. General historical remarks of PACS and international scene in three stages from infancy, puberty to adolescence are presented. Early PACS development was mostly financed by the federal government including the National Institutes of Health (NIH) and the U.S. Army Medical Research and Materiel Command. PACS evolution went through several stages. The earliest stages included the definition of large-scale PACS, establishment of the DICOM and other standards, the development of some early key PACS related technologies, and PACS implementation strategies. The later stages were in the concept of enterprise PACS, IHE (Integrating the Healthcare Enterprise) workflow profiles, and ePR with image distribution. The current most excited accomplishment is in the development of the new field in medical imaging informatics. This review goes through these stages and events in the USA during these 28 years, whenever an event involved participants from other countries, the contributors are cited. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Short history of PACS. Part I: USA

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.K., E-mail: hkhuang@aol.com [Departments of Radiology and Biomedical Engineering, University of Southern California (United States); Hong Kong Polytechnic University (Hong Kong); Shanghai Institute of Technical Physics, Chinese Academy of Sciences (China)

    2011-05-15

    This historical review covers the PACS development in the USA during the past 28 years from 1982 to 2010. General historical remarks of PACS and international scene in three stages from infancy, puberty to adolescence are presented. Early PACS development was mostly financed by the federal government including the National Institutes of Health (NIH) and the U.S. Army Medical Research and Materiel Command. PACS evolution went through several stages. The earliest stages included the definition of large-scale PACS, establishment of the DICOM and other standards, the development of some early key PACS related technologies, and PACS implementation strategies. The later stages were in the concept of enterprise PACS, IHE (Integrating the Healthcare Enterprise) workflow profiles, and ePR with image distribution. The current most excited accomplishment is in the development of the new field in medical imaging informatics. This review goes through these stages and events in the USA during these 28 years, whenever an event involved participants from other countries, the contributors are cited.

  16. PACS influence the radiographer's work

    International Nuclear Information System (INIS)

    Fridell, Kent; Aspelin, Peter; Edgren, Lars; Lindskoeld, Lars; Lundberg, Nina

    2009-01-01

    Radiological departments are changing rapidly due to the implementation of digital images and PACS (Picture Archiving and Communication Systems). The introduction of new technology seems to dissolve boundaries between the professions in the work environment where the technology is introduced. This process tends to change the organization and its routines. The aim of this qualitative study is to explore changes in radiographers' work with regard to skills, work practice and technology. The study used open-ended interviews to explore the radiographers' perceptions of such changes, and to identify problems and solutions pertaining to work practice. Inspiration is taken from grounded theory to explain the changes in work that were found. Respondents were selected from a total of 133 potential participants as a theoretical or purposive sample. The changing trends within the professional role indicated that radiographers, as image producers, shifted their focus from the ability to set the optimal exposure parameters in order to obtain the optimal image for diagnosis to become expert in exposure parameters, projection techniques and diagnostic practice, having multifaceted skills, as being the jack of all trades. When implementing PACS there was an obvious change in image production. At the start there were visions of new routines, and therefore the radiographers became early adopters to the new technology; in practice the organization was stacked in old routines, as the routines were inflexible and PACS work was pushed into old work routines. Although inflexible, this does not mean that they cannot change, and obviously in 2006 new routines had been implemented making it possible for the radiographers in finding new ways for collaborating with colleagues. The new technology immediately created a vision of improved service to the clinicians. In order to optimize the service the radiographers developed an insight into the need for a more comprehensive change in work using

  17. Photometric Uncertainties

    Science.gov (United States)

    Zou, Xiao-Duan; Li, Jian-Yang; Clark, Beth Ellen; Golish, Dathon

    2018-01-01

    The OSIRIS-REx spacecraft, launched in September, 2016, will study the asteroid Bennu and return a sample from its surface to Earth in 2023. Bennu is a near-Earth carbonaceous asteroid which will provide insight into the formation and evolution of the solar system. OSIRIS-REx will first approach Bennu in August 2018 and will study the asteroid for approximately two years before sampling. OSIRIS-REx will develop its photometric model (including Lommel-Seelinger, ROLO, McEwen, Minnaert and Akimov) of Bennu with OCAM and OVIRS during the Detailed Survey mission phase. The model developed during this phase will be used to photometrically correct the OCAM and OVIRS data.Here we present the analysis of the error for the photometric corrections. Based on our testing data sets, we find:1. The model uncertainties is only correct when we use the covariance matrix to calculate, because the parameters are highly correlated.2. No evidence of domination of any parameter in each model.3. And both model error and the data error contribute to the final correction error comparably.4. We tested the uncertainty module on fake and real data sets, and find that model performance depends on the data coverage and data quality. These tests gave us a better understanding of how different model behave in different case.5. L-S model is more reliable than others. Maybe because the simulated data are based on L-S model. However, the test on real data (SPDIF) does show slight advantage of L-S, too. ROLO is not reliable to use when calculating bond albedo. The uncertainty of McEwen model is big in most cases. Akimov performs unphysical on SOPIE 1 data.6. Better use L-S as our default choice, this conclusion is based mainly on our test on SOPIE data and IPDIF.

  18. PACS for the Developing World

    Directory of Open Access Journals (Sweden)

    Jeffrey B. Mendel

    2015-11-01

    Full Text Available Digital imaging is now firmly ensconced in the developed world. Its widespread adoption has enabled instant access to images, remote viewing, remote consultation, and the end of lost or misplaced film. Unfortunately, the current paradigm of Picture Archiving and Communication System (PACS, with advanced technology inseparable from high complexity, high purchase costs, and high maintenance costs, is not suited for the low-income developing world. Like the simple, easy to repair, 1950’s American cars still running on the streets of Havana, the developing world requires a PACS (DW-PACS that can perform basic functions and survive in a limited-resource environment. The purpose of this article is to more fully describe this concept and to present a blueprint for PACS tailored to the needs and resources of the developing world. This framework should assist both users looking for a vendor-supplied or open-source solutions and developers seeking to address the needs of this emerging market.

  19. Quantitative surface topography assessment of directly compressed and roller compacted tablet cores using photometric stereo image analysis.

    Science.gov (United States)

    Allesø, Morten; Holm, Per; Carstensen, Jens Michael; Holm, René

    2016-05-25

    Surface topography, in the context of surface smoothness/roughness, was investigated by the use of an image analysis technique, MultiRay™, related to photometric stereo, on different tablet batches manufactured either by direct compression or roller compaction. In the present study, oblique illumination of the tablet (darkfield) was considered and the area of cracks and pores in the surface was used as a measure of tablet surface topography; the higher a value, the rougher the surface. The investigations demonstrated a high precision of the proposed technique, which was able to rapidly (within milliseconds) and quantitatively measure the obtained surface topography of the produced tablets. Compaction history, in the form of applied roll force and tablet punch pressure, was also reflected in the measured smoothness of the tablet surfaces. Generally it was found that a higher degree of plastic deformation of the microcrystalline cellulose resulted in a smoother tablet surface. This altogether demonstrated that the technique provides the pharmaceutical developer with a reliable, quantitative response parameter for visual appearance of solid dosage forms, which may be used for process and ultimately product optimization. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Photometric Calibration of the Barium Cloud Image in a Space Active Experiment: Determining the Release Efficiency

    International Nuclear Information System (INIS)

    Xie Liang-Hai; Li Lei; Wang Jing-Dong; Tao Ran; Cheng Bing-Jun; Zhang Yi-Teng

    2014-01-01

    The barium release experiment is an effective method to explore the near-earth environment and to study all kinds of space physics processes. The first space barium release experiment in China was successfully carried out by a sounding rocket on April 5, 2013. This work is devoted to calculating the release efficiency of the barium release by analyzing the optical image observed during the experiment. First, we present a method to calibrate the images grey value of barium cloud with the reference stars to obtain the radiant fluxes at different moments. Then the release efficiency is obtained by a curve fitting with the theoretical evolution model of barium cloud. The calculated result is basically consistent with the test value on ground

  1. Multiview photometric stereo.

    Science.gov (United States)

    Hernández Esteban, Carlos; Vogiatzis, George; Cipolla, Roberto

    2008-03-01

    This paper addresses the problem of obtaining complete, detailed reconstructions of textureless shiny objects. We present an algorithm which uses silhouettes of the object, as well as images obtained under changing illumination conditions. In contrast with previous photometric stereo techniques, ours is not limited to a single viewpoint but produces accurate reconstructions in full 3D. A number of images of the object are obtained from multiple viewpoints, under varying lighting conditions. Starting from the silhouettes, the algorithm recovers camera motion and constructs the object's visual hull. This is then used to recover the illumination and initialise a multi-view photometric stereo scheme to obtain a closed surface reconstruction. There are two main contributions in this paper: Firstly we describe a robust technique to estimate light directions and intensities and secondly, we introduce a novel formulation of photometric stereo which combines multiple viewpoints and hence allows closed surface reconstructions. The algorithm has been implemented as a practical model acquisition system. Here, a quantitative evaluation of the algorithm on synthetic data is presented together with complete reconstructions of challenging real objects. Finally, we show experimentally how even in the case of highly textured objects, this technique can greatly improve on correspondence-based multi-view stereo results.

  2. Current developments in departmental PACS for ultrasound.

    Science.gov (United States)

    Grenier, L E; Eng, P

    1995-01-01

    1. INTRODUCTION TO DEPARTMENTAL PACS. Full or partial Departmental PACS is generally taken to mean an image management system focused on serving the needs of a specific modality or modality application. It will provide a modality specific means of image acquisition, specialized redisplay of images, distribution, and local long term storage of images. A Departmental PACS can be considered in isolation or as a component in a distributed Radiology PACS which consists of one or more departmental work groups on a back bone, potentially with shared resources. 2. DEPARTMENTAL PACS Issues Implementation of a Departmental PACS requires an in-depth knowledge of departmental clinical practice and work flow in all affected areas in the department, including patient intake, image collection, data routing, retrieval of previous image data, reporting, and long term data management and storage. Optimization of modality specific image display systems requires significant involvement from representative physician users. System architectures and user interfaces must be flexible enough to support the span of variation in clinical practice encountered in the site. A departmental PACS should offer a variety of "open" communications interfaces, both local and wide area, recognizing that outreach efforts are often driven by specific imaging departments. Interfaces to other departmental PAC systems and other information systems must be considered in order to facilitate institutions developing "Best of Breed" PACS systems. As hospitals move toward the integrated electronic medical record, means need to exist for a client process launched from a physician desktop to acquire images and/or reports from a departmental system. At minimum, HIS/RIS interfaces need to be considered to minimize re-keying of data and reduce data entry errors. 3. DESIGN OBJECTIVES FOR ALI ULTRAPACS. The key objectives were to design a product which could function either as a free standing PACS or as a departmental

  3. PAC research in biology

    Energy Technology Data Exchange (ETDEWEB)

    Chain, C. Y., E-mail: yamil@fisica.unlp.edu.ar [Universidad Nacional de La Plata, IFLP (Argentina); Ceolin, M. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas, Dto de Quimica, Fac. Cs. Exactas, UNLP (Argentina); Pasquevich, A. F. [Universidad Nacional de La Plata, IFLP (Argentina)

    2008-01-15

    In this paper possible applications of the Perturbed Angular Correlations (PAC) technique in Biology are considered. Previous PAC experiments in biology are globally analyzed. All the work that appears in the literature has been grouped in a few research lines, just to make the analysis and discussion easy. The commonly used radioactive probes are listed and the experimental difficulties are analyzed. We also report applications of {sup 181}Hf and {sup 111}In isotopes in life sciences other than their use in PAC. The possibility of extending these studies using the PAC technique is discussed.

  4. Ex vivo photometric and polarimetric multilayer characterization of human healthy colon by multispectral Mueller imaging.

    Science.gov (United States)

    Pierangelo, Angelo; Manhas, Sandeep; Benali, Abdelali; Fallet, Clément; Antonelli, Maria-Rosaria; Novikova, Tatiana; Gayet, Brice; Validire, Pierre; De Martino, Antonello

    2012-06-01

    Healthy human colon samples were analyzed ex vivo with a multispectral imaging Mueller polarimeter operating from 500 to 700 nm in a backscattering configuration with diffuse light illumination impinging on the innermost tissue layer, the mucosa. The intensity and polarimetric responses were taken on whole tissues first and after progressive exfoliation of the outer layers afterwards. Moreover, these measurements were carried out with two different substrates (one bright and the other dark) successively placed beneath each sample, allowing a reasonably accurate evaluation of the contributions to the overall backscattered light by the various layers. For the shorter investigated wavelengths (500 to 550 nm) the major contribution comes from mucosa and submucosa, while for the longer wavelengths (650 to 700 nm) muscular tissue and fat also contribute significantly. The depolarization has also been studied and is found to be stronger in the red part of the spectrum, mainly due to the highly depolarizing power of the muscular and fat layers.

  5. IHE profiles applied to regional PACS

    International Nuclear Information System (INIS)

    Fernandez-Bayo, Josep

    2011-01-01

    PACS has been widely adopted as an image storage solution that perfectly fits the radiology department workflow and that can be easily extended to other hospital departments. Integrations with other hospital systems, like the Radiology Information System, the Hospital Information System and the Electronic Patient Record are fully achieved but still challenging aims. PACS also creates the perfect environment for teleradiology and teleworking setups. One step further is the regional PACS concept where different hospitals or health care enterprises share the images in an integrated Electronic Patient Record. Among the different solutions available to share images between different hospitals IHE (Integrating the Healthcare Enterprise) organization presents the Cross Enterprise Document Sharing profile (XDS) which allows sharing images from different hospitals even if they have different PACS vendors. Adopting XDS has multiple advantages, images do not need to be duplicated in a central archive to be shared among the different healthcare enterprises, they only need to be indexed and published in a central document registry. In the XDS profile IHE defines the mechanisms to publish and index the images in the central document registry. It also defines the mechanisms that each hospital will use to retrieve those images regardless on the Hospital PACS they are stored.

  6. SU-E-I-75: Development of New Biological Fingerprints for Patient Recognition to Identify Misfiled Images in a PACS Server

    International Nuclear Information System (INIS)

    Shimizu, Y; Yoon, Y; Iwase, K; Yasumatsu, S; Matsunobu, Y; Morishita, J

    2015-01-01

    Purpose: We are trying to develop an image-searching technique to identify misfiled images in a picture archiving and communication system (PACS) server by using five biological fingerprints: the whole lung field, cardiac shadow, superior mediastinum, lung apex, and right lower lung. Each biological fingerprint in a chest radiograph includes distinctive anatomical structures to identify misfiled images. The whole lung field was less effective for evaluating the similarity between two images than the other biological fingerprints. This was mainly due to the variation in the positioning for chest radiographs. The purpose of this study is to develop new biological fingerprints that could reduce influence of differences in the positioning for chest radiography. Methods: Two hundred patients were selected randomly from our database (36,212 patients). These patients had two images each (current and previous images). Current images were used as the misfiled images in this study. A circumscribed rectangular area of the lung and the upper half of the rectangle were selected automatically as new biological fingerprints. These biological fingerprints were matched to all previous images in the database. The degrees of similarity between the two images were calculated for the same and different patients. The usefulness of new the biological fingerprints for automated patient recognition was examined in terms of receiver operating characteristic (ROC) analysis. Results: Area under the ROC curves (AUCs) for the circumscribed rectangle of the lung, upper half of the rectangle, and whole lung field were 0.980, 0.994, and 0.950, respectively. The new biological fingerprints showed better performance in identifying the patients correctly than the whole lung field. Conclusion: We have developed new biological fingerprints: circumscribed rectangle of the lung and upper half of the rectangle. These new biological fingerprints would be useful for automated patient identification system

  7. SU-E-I-75: Development of New Biological Fingerprints for Patient Recognition to Identify Misfiled Images in a PACS Server

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Y; Yoon, Y; Iwase, K; Yasumatsu, S; Matsunobu, Y [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, JP (Japan); Morishita, J [Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, Fukuoka, JP (Japan)

    2015-06-15

    Purpose: We are trying to develop an image-searching technique to identify misfiled images in a picture archiving and communication system (PACS) server by using five biological fingerprints: the whole lung field, cardiac shadow, superior mediastinum, lung apex, and right lower lung. Each biological fingerprint in a chest radiograph includes distinctive anatomical structures to identify misfiled images. The whole lung field was less effective for evaluating the similarity between two images than the other biological fingerprints. This was mainly due to the variation in the positioning for chest radiographs. The purpose of this study is to develop new biological fingerprints that could reduce influence of differences in the positioning for chest radiography. Methods: Two hundred patients were selected randomly from our database (36,212 patients). These patients had two images each (current and previous images). Current images were used as the misfiled images in this study. A circumscribed rectangular area of the lung and the upper half of the rectangle were selected automatically as new biological fingerprints. These biological fingerprints were matched to all previous images in the database. The degrees of similarity between the two images were calculated for the same and different patients. The usefulness of new the biological fingerprints for automated patient recognition was examined in terms of receiver operating characteristic (ROC) analysis. Results: Area under the ROC curves (AUCs) for the circumscribed rectangle of the lung, upper half of the rectangle, and whole lung field were 0.980, 0.994, and 0.950, respectively. The new biological fingerprints showed better performance in identifying the patients correctly than the whole lung field. Conclusion: We have developed new biological fingerprints: circumscribed rectangle of the lung and upper half of the rectangle. These new biological fingerprints would be useful for automated patient identification system

  8. Web based emergency room PACS

    International Nuclear Information System (INIS)

    Cha, Soon Joo; Cheon, Yong Kyung; Choi, Sung Woo Kim

    2005-01-01

    We wished to develop the web based Picture Archiving and Communication System in the emergency room for early decision making in emergency treatment planning at a full PACS Hospital. The program tools were Microsoft Visual Studio 6.0 - Visual C++ 6.0, and the Microsoft SQL 7.0 under the Microsoft Windows 2000 server operation system. The achievement of images was performed by an auto transport program installed in the ER and the radiology department. The average compression rates were 5:1 for CT and MR, and 20:1 for CR with JPEG 2000 lossy compression. All the images were stored on hard disk for 3 months. The patients' information was displayed for 2 weeks for reducing the security risk. For interdepartmental consultation, patient query by patient hospital number was available. Our Web based ER PACS could be useful system for early decision making for treatment planning in the emergency room because it reduces the risk factors for the security of the Web Paces by using a system independent from PACS in the hospital and minimizing the information patients

  9. Web based emergency room PACS

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Soon Joo; Cheon, Yong Kyung; Choi, Sung Woo Kim [Ilsan Paik Hospital, Inje University, Seoul (Korea, Republic of)] (and others)

    2005-07-15

    We wished to develop the web based Picture Archiving and Communication System in the emergency room for early decision making in emergency treatment planning at a full PACS Hospital. The program tools were Microsoft Visual Studio 6.0 - Visual C++ 6.0, and the Microsoft SQL 7.0 under the Microsoft Windows 2000 server operation system. The achievement of images was performed by an auto transport program installed in the ER and the radiology department. The average compression rates were 5:1 for CT and MR, and 20:1 for CR with JPEG 2000 lossy compression. All the images were stored on hard disk for 3 months. The patients' information was displayed for 2 weeks for reducing the security risk. For interdepartmental consultation, patient query by patient hospital number was available. Our Web based ER PACS could be useful system for early decision making for treatment planning in the emergency room because it reduces the risk factors for the security of the Web Paces by using a system independent from PACS in the hospital and minimizing the information patients.

  10. The future of PACS in healthcare enterprises

    International Nuclear Information System (INIS)

    Faggioni, Lorenzo; Neri, Emanuele; Castellana, Carlo; Caramella, Davide; Bartolozzi, Carlo

    2011-01-01

    Picture Archiving and Communication System (PACS), which was originally designed as a tool for facilitating radiologists in interpreting images more efficiently, is evolving into a hospital-integrated system storing diagnostic imaging information that often reaches far beyond Radiology. The continuous evolution of PACS technology has led to a gradual broadening of its applications, ranging from teleradiology to CAD (Computer-Assisted Diagnosis) and multidimensional imaging, and is moving into the direction of providing access to image data outside the Radiology department, so to reach all the branches of the healthcare enterprise. New perspectives have been created thanks to new technologies (such as holographic media and GRID computing) that are likely due to expand PACS-based applications even further, improving patient care and enhancing overall productivity.

  11. Reliability issues in PACS

    Science.gov (United States)

    Taira, Ricky K.; Chan, Kelby K.; Stewart, Brent K.; Weinberg, Wolfram S.

    1991-07-01

    Reliability is an increasing concern when moving PACS from the experimental laboratory to the clinical environment. Any system downtime may seriously affect patient care. The authors report on the several classes of errors encountered during the pre-clinical release of the PACS during the past several months and present the solutions implemented to handle them. The reliability issues discussed include: (1) environmental precautions, (2) database backups, (3) monitor routines of critical resources and processes, (4) hardware redundancy (networks, archives), and (5) development of a PACS quality control program.

  12. THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC): DEEP MEDIUM-BAND OPTICAL IMAGING AND HIGH-QUALITY 32-BAND PHOTOMETRIC REDSHIFTS IN THE ECDF-S

    International Nuclear Information System (INIS)

    Cardamone, Carolin N.; Van Dokkum, Pieter G.; Urry, C. Megan; Brammer, Gabriel; Taniguchi, Yoshi; Gawiser, Eric; Bond, Nicholas; Taylor, Edward; Damen, Maaike; Treister, Ezequiel; Cobb, Bethany E.; Schawinski, Kevin; Lira, Paulina; Murayama, Takashi; Saito, Tomoki; Sumikawa, Kentaro

    2010-01-01

    We present deep optical 18-medium-band photometry from the Subaru telescope over the ∼30' x 30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC 'BVR' image we find ∼40,000 galaxies with R AB 3.5. For 0.1 < z < 1.2, we find a 1σ scatter in Δz/(1 + z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1 < z < 1.2. We find that ∼20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site.

  13. Current status of the UCSF second-generation PACS

    Science.gov (United States)

    Huang, H. K.; Arenson, Ronald L.; Wong, Albert W. K.; Bazzill, Todd M.; Lou, Shyhliang A.; Andriole, Katherine P.; Wang, Jun; Zhang, Jianguo; Wong, Stephen T. C.

    1996-05-01

    This paper describes the current status of the second generation PACS at UCSF commenced in October 1992. The UCSF PACS is designed in-house as a hospital-integrated PACS based on an open architecture concept using industrial standards including UNIX operating system, C programming language, X-Window user interface, TCP/IP communication protocol, DICOM 3.0 image standard and HL7 health data format. Other manufacturer's PACS components which conform with these standards can be easily integrated into the system. Relevant data from HIS and RIS is automatically incorporated into the PACS using HL7 data format and TCP/IP communication protocol. The UCSF system also takes advantage of state-of-the-art communication, storage, and software technologies in ATM, multiple storage media, automatic programming, multilevel processes for a better cost-performance system. The primary PACS network is the 155 Mbits/sec OC3 ATM with the Ethernet as the back-up. The UCSF PACS also connects Mt. Zion Hospital and San Francisco VA Medical Center in the San Francisco Bay area via an ATM wide area network with a T1 line as the back-up. Currently, five MR and five CT scanners from multiple sites, two computed radiography systems, two film digitizers, one US PACS module, the hospital HIS and the department RIS have been connected to the PACS network. The image data is managed by a mirrored database (Sybase). The PACS controller, with its 1.3 terabyte optical disk library, acquires 2.5 gigabytes digital data daily. Four 2K, five, 1,600-line multiple monitor display workstations are on line in neuroradiology, pediatric radiology and intensive care units for clinical use. In addition, the PACS supports over 100 Macintosh users in the department and selected hospital sites for both images and textual retrieval through a client/server mechanism. We are also developing a computation and visualization node in the PACS network for advancing radiology research.

  14. Role of pacs in an integrated communication system

    International Nuclear Information System (INIS)

    Thompson, B.G.; Creasy, J.L.; Johnston, R.E.; Parrish, D.; Scatliff, J.H.

    1986-01-01

    An integrated computer-based communications system uses multiple computers for the high speed transmission, storage, enhancement and display for medical information. Interconnected by a network such as coaxial and fiberoptic cables or microwave stations, the system would provide integrated communications throughout a satellite medical environment. As the availability of proven PACS components becomes a commercial reality, migratory expansion of PACS within the radiology clinical, educational and research areas will be possible. When the PACS is integrated with hospital, radiology and medical school information systems it provides the image component of a total medical information system. Current PACS efforts are on a research basis including the development of prototype systems. This paper provides an overview of implementation strategies. Issues to be discussed include PACS research objectives, typical implementation methods, and a review of interactions between PACS and radiology information systems (RIS) and hospital information systems

  15. The HERSCHEL/PACS early Data Products

    Science.gov (United States)

    Wieprecht, E.; Wetzstein, M.; Huygen, R.; Vandenbussche, B.; De Meester, W.

    2006-07-01

    ESA's Herschel Space Observatory to be launched in 2007, is the first space observatory covering the full far-infrared and submillimeter wavelength range (60 - 670 microns). The Photodetector Array Camera & Spectrometer (PACS) is one of the three science instruments. It contains two Ge:Ga photoconductor arrays and two bolometer arrays to perform imaging line spectroscopy and imaging photometry in the 60 - 210 micron wavelength band. The HERSCHEL ground segment (Herschel Common Science System - HCSS) is implemented using JAVA technology and written in a common effort by the HERSCHEL Science Center and the three instrument teams. The PACS Common Software System (PCSS) is based on the HCSS and used for the online and offline analysis of PACS data. For telemetry bandwidth reasons PACS science data are partially processed on board, compressed, cut into telemetry packets and transmitted to the ground. These steps are instrument mode dependent. We will present the software model which allows to reverse the discrete on board processing steps and evaluate the data. After decompression and reconstruction the detector data and instrument status information are organized in two main PACS Products. The design of these JAVA classes considers the individual sampling rates, data formats, memory and performance optimization aspects and comfortable user interfaces.

  16. PACS: Picture Archiving and Communication Systems

    International Nuclear Information System (INIS)

    Gell, G.; Schneider, G.H.; Becker, M.; Wiltgen, M.

    1988-01-01

    A growing number of medical imaging modalities produces images that are initially calculated and stored as digital information in a computer. For diagnosis, archiving and communication a hardcopy (usually on X-ray film) is produced from these data. It is estimated that in 1995 about 80% of all imaging procedures will generate digital images. This trend leads to the development of systems, where the X-ray film is not only replaced in his function as a radiation detector, but also in his other functions as the medium for image presentation, image communication and image archiving. In short, one wants a completely digital picture archiving and communication system (PACS). The rationale behind PACS efforts is to achieve better functionality and to save costs, mainly by reducing the consumption of expensive X-ray films and the need for storage space for film archives. 7 refs., 2 figs. (Author)

  17. PACS: implementation in the U.S. Department of Defense

    Science.gov (United States)

    Chacko, Anna K.; Wider, Ronald; Romlein, John R.; Cawthon, Michael A.; Richardson, Ronald R., Jr.; Lollar, H. William; Cook, Jay F.; Timboe, Harold L.; Johnson, Thomas G.; Fellows, Douglas W.

    2000-05-01

    The Department of Defense has been a leader in Radiology re- engineering for the past decade. Efforts have included the development of two landmark PACS specifications (MDIS and DIN- PACS), respective vendor selection and implementation programs. A Tri-Service (Army, Navy and Air Force) Radiology re-engineering program was initiated which identified transitioning to digital imaging, PACS and teleradiology as key enabling technologies in a changing business scenario. Subsequently, the systematic adjustment of procurement process for radiological imaging equipment included a focus on specifying PACS-capable-digital imaging modalities and mini- PACS as stepping stones to make the hospitals and health clinics PACS-ready. The success of the PACS and teleradiology program in the DOD is evidenced by the near filmless operation of most Army and Air Force Medical Centers, several community hospitals and several operational teleradiology constellations. Additionally, the MDIS PACSystem has become the commercial PACS product for General Electric Medical Systems. The DOD continues to forge ahead in the PACS arena by implementing advanced configurations and operational concepts such as the VRE (Virtual Radiology Environment), the negotiation of Regional Archiving and Regional PACS Maintenance Programs. Newer regulations (HIPAA, the FDA approval of digital mammography) have been promulgated impacting the culture and conduct of our business. Incorporating their requirements at the very outset will enable us to streamline the delivery of radiology. The DOD community has embraced the information age at multiple levels. The Healthcare portion of this community with these initiatives is integrating itself into DOD's future. The future holds great possibilities, promises and challenges for the DOD PACS programs.

  18. PACS administrators' and radiologists' perspective on the importance of features for PACS selection.

    Science.gov (United States)

    Joshi, Vivek; Narra, Vamsi R; Joshi, Kailash; Lee, Kyootai; Melson, David

    2014-08-01

    Picture archiving and communication systems (PACS) play a critical role in radiology. This paper presents the criteria important to PACS administrators for selecting a PACS. A set of criteria are identified and organized into an integrative hierarchical framework. Survey responses from 48 administrators are used to identify the relative weights of these criteria through an analytical hierarchy process. The five main dimensions for PACS selection in order of importance are system continuity and functionality, system performance and architecture, user interface for workflow management, user interface for image manipulation, and display quality. Among the subdimensions, the highest weights were assessed for security, backup, and continuity; tools for continuous performance monitoring; support for multispecialty images; and voice recognition/transcription. PACS administrators' preferences were generally in line with that of previously reported results for radiologists. Both groups assigned the highest priority to ensuring business continuity and preventing loss of data through features such as security, backup, downtime prevention, and tools for continuous PACS performance monitoring. PACS administrators' next high priorities were support for multispecialty images, image retrieval speeds from short-term and long-term storage, real-time monitoring, and architectural issues of compatibility and integration with other products. Thus, next to ensuring business continuity, administrators' focus was on issues that impact their ability to deliver services and support. On the other hand, radiologists gave high priorities to voice recognition, transcription, and reporting; structured reporting; and convenience and responsiveness in manipulation of images. Thus, radiologists' focus appears to be on issues that may impact their productivity, effort, and accuracy.

  19. Trends in PACS architecture

    International Nuclear Information System (INIS)

    Bellon, Erwin; Feron, Michel; Deprez, Tom; Reynders, Reinoud; Van den Bosch, Bart

    2011-01-01

    Radiological Picture Archiving and Communication Systems (PACS) have only relatively recently become abundant. Many hospitals have made the transition to PACS about a decade ago. During that decade requirements and available technology have changed considerably. In this paper we look at factors that influence the design of tomorrow's systems, especially those in larger multidisciplinary hospitals. We discuss their impact on PACS architecture (a technological perspective) as well as their impact on radiology (a management perspective). We emphasize that many of these influencing factors originate outside radiology and that radiology has little impact on these factors. That makes it the more important for managers in radiology to be aware of architectural aspects and it may change cooperation of radiology with, among others, the hospital's central IT department.

  20. PACS quality control and automatic problem notifier

    Science.gov (United States)

    Honeyman-Buck, Janice C.; Jones, Douglas; Frost, Meryll M.; Staab, Edward V.

    1997-05-01

    One side effect of installing a clinical PACS Is that users become dependent upon the technology and in some cases it can be very difficult to revert back to a film based system if components fail. The nature of system failures range from slow deterioration of function as seen in the loss of monitor luminance through sudden catastrophic loss of the entire PACS networks. This paper describes the quality control procedures in place at the University of Florida and the automatic notification system that alerts PACS personnel when a failure has happened or is anticipated. The goal is to recover from a failure with a minimum of downtime and no data loss. Routine quality control is practiced on all aspects of PACS, from acquisition, through network routing, through display, and including archiving. Whenever possible, the system components perform self and between platform checks for active processes, file system status, errors in log files, and system uptime. When an error is detected or a exception occurs, an automatic page is sent to a pager with a diagnostic code. Documentation on each code, trouble shooting procedures, and repairs are kept on an intranet server accessible only to people involved in maintaining the PACS. In addition to the automatic paging system for error conditions, acquisition is assured by an automatic fax report sent on a daily basis to all technologists acquiring PACS images to be used as a cross check that all studies are archived prior to being removed from the acquisition systems. Daily quality control is preformed to assure that studies can be moved from each acquisition and contrast adjustment. The results of selected quality control reports will be presented. The intranet documentation server will be described with the automatic pager system. Monitor quality control reports will be described and the cost of quality control will be quantified. As PACS is accepted as a clinical tool, the same standards of quality control must be established

  1. MedPAC Data Book

    Data.gov (United States)

    U.S. Department of Health & Human Services — MedPACs Data Book is the result of discussions with congressional staff members regarding ways that MedPAC can better support them. Some of the information it...

  2. PACS infrastructure supporting e-learning

    International Nuclear Information System (INIS)

    Mildenberger, Peter; Brueggemann, Kerstin; Roesner, Freya; Koch, Katja; Ahlers, Christopher

    2011-01-01

    Digital imaging is becoming predominant in radiology. This has implications for teaching support, because conventional film-based concepts are now obsolete. The IHE Teaching File and Clinical Study Export (TCE) profile provides an excellent platform to enhance PACS infrastructure with educational functionality. This can be supplemented with dedicated e-learning tools.

  3. PACS infrastructure supporting e-learning

    Energy Technology Data Exchange (ETDEWEB)

    Mildenberger, Peter, E-mail: milden@radiologie.klinik.uni-mainz.de [University Medicine Mainz, Johannes Gutenberg-University Mainz, Langenbeckstr 1, Mainz (Germany); Brueggemann, Kerstin; Roesner, Freya; Koch, Katja; Ahlers, Christopher [University Medicine Mainz, Johannes Gutenberg-University Mainz, Langenbeckstr 1, Mainz (Germany)

    2011-05-15

    Digital imaging is becoming predominant in radiology. This has implications for teaching support, because conventional film-based concepts are now obsolete. The IHE Teaching File and Clinical Study Export (TCE) profile provides an excellent platform to enhance PACS infrastructure with educational functionality. This can be supplemented with dedicated e-learning tools.

  4. Statistical learning modeling method for space debris photometric measurement

    Science.gov (United States)

    Sun, Wenjing; Sun, Jinqiu; Zhang, Yanning; Li, Haisen

    2016-03-01

    Photometric measurement is an important way to identify the space debris, but the present methods of photometric measurement have many constraints on star image and need complex image processing. Aiming at the problems, a statistical learning modeling method for space debris photometric measurement is proposed based on the global consistency of the star image, and the statistical information of star images is used to eliminate the measurement noises. First, the known stars on the star image are divided into training stars and testing stars. Then, the training stars are selected as the least squares fitting parameters to construct the photometric measurement model, and the testing stars are used to calculate the measurement accuracy of the photometric measurement model. Experimental results show that, the accuracy of the proposed photometric measurement model is about 0.1 magnitudes.

  5. Shimadzu AI-PACS 'SAIPACS'

    International Nuclear Information System (INIS)

    Andoh, Minoru; Asai, Shigeya; Matsui, Norihisa; Nishida, Shinichiro; Horino, Masato

    1990-01-01

    The PACS-WS named SAIPACS-WS(workstation) has been developed as the first step of complete PACS. This SAIPACS-WS is different from other PACS-WS's, because this is including computer aided diagnostic reporting and computer aided diagnosis by using artificial intelligence technique. In this paper we will report detail of the SAIPACS-WS and discuss the future development of the total PACS setting the SAIPACS-WS in its center. (author)

  6. A strategic PACS maturity approach

    NARCIS (Netherlands)

    van de Wetering, R.

    2011-01-01

    Finding the key determinants of Picture Archivingand Communication Systems (PACS)performance in hospitals has been a conundrumfor decades. This research provides a method toassess the strategic alignment of PACS in hospitalsin order to find these key determinants. PACS touches upon every single part

  7. REVIEW ARTICLE REVI REVI Talking PACS: Part 1 – What is PACS?

    African Journals Online (AJOL)

    Image management is the administration of imaging examination requests, the performance of ... responsibility dependent on a long chain of human interaction that often fails. Within both ... This is an information system responsible for the storage, distribution .... This refers to a computer interface to gain access to the PACS.

  8. Satellite Photometric Error Determination

    Science.gov (United States)

    2015-10-18

    Satellite Photometric Error Determination Tamara E. Payne, Philip J. Castro, Stephen A. Gregory Applied Optimization 714 East Monument Ave, Suite...advocate the adoption of new techniques based on in-frame photometric calibrations enabled by newly available all-sky star catalogs that contain highly...filter systems will likely be supplanted by the Sloan based filter systems. The Johnson photometric system is a set of filters in the optical

  9. A DICOM based PACS for nuclear medicine

    International Nuclear Information System (INIS)

    Lassmann, M.; Reiners, C.

    2002-01-01

    The installation of a radiology information system (RIS) connected to a hospital information system (HIS) and a picture archiving and communications system (PACS) seems mandatory for a nuclear medicine department in order to guarantee a high patient throughput. With these systems a fast transmission of reports, images to the in- and out-patients' wards and private practitioners is realized. Therefore, since April 2000, at the department of nuclear medicine of the university of Wuerzburg a completely DICOM based PACS has been implemented in addition to the RIS. With this system a DICOM based workflow is realized throughout the department of nuclear medicine for reporting and archiving. The PACS is connected to six gamma-cameras, a PET scanner, a bone densitometry system and an ultrasound device. The volume of image data archived per month is 4 GByte. Patient demographics are provided to the modalities via DICOM-Worklist. With these PACS components a department specific archive purely based on DICOM can be realized. During the installation process problems occurred mainly because of the complex DICOM standard for nuclear medicine. Related to that is the problem that most of the software implementations still contain bugs or are not adapted to the needs of a nuclear medicine department (particularly for PET). A communication software for the distribution of nuclear medicine reports and images based on techniques used for the worldwide web is currently tested. (orig.) [de

  10. Three-dimensional stereo by photometric ratios

    International Nuclear Information System (INIS)

    Wolff, L.B.; Angelopoulou, E.

    1994-01-01

    We present a methodology for corresponding a dense set of points on an object surface from photometric values for three-dimensional stereo computation of depth. The methodology utilizes multiple stereo pairs of images, with each stereo pair being taken of the identical scene but under different illumination. With just two stereo pairs of images taken under two different illumination conditions, a stereo pair of ratio images can be produced, one for the ratio of left-hand images and one for the ratio of right-hand images. We demonstrate how the photometric ratios composing these images can be used for accurate correspondence of object points. Object points having the same photometric ratio with respect to two different illumination conditions constitute a well-defined equivalence class of physical constraints defined by local surface orientation relative to illumination conditions. We formally show that for diffuse reflection the photometric ratio is invariant to varying camera characteristics, surface albedo, and viewpoint and that therefore the same photometric ratio in both images of a stereo pair implies the same equivalence class of physical constraints. The correspondence of photometric ratios along epipolar lines in a stereo pair of images under different illumination conditions is a correspondence of equivalent physical constraints, and the determination of depth from stereo can be performed. Whereas illumination planning is required, our photometric-based stereo methodology does not require knowledge of illumination conditions in the actual computation of three-dimensional depth and is applicable to perspective views. This technique extends the stereo determination of three-dimensional depth to smooth featureless surfaces without the use of precisely calibrated lighting. We demonstrate experimental depth maps from a dense set of points on smooth objects of known ground-truth shape, determined to within 1% depth accuracy

  11. THE EXTRAORDINARY FAR-INFRARED VARIATION OF A PROTOSTAR: HERSCHEL/PACS OBSERVATIONS OF LRLL54361

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Zoltan; Detre, Örs H.; Bouwmann, Jeroen; Nielbock, Markus; Klaas, Ulrich; Krause, Oliver; Henning, Thomas [Max Planck Institute for Astronomy Königstuhl 17, Heidelberg D-69117 (Germany); Muzerolle, James [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Flaherty, Kevin [Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States); Furlan, Elise [Natinal Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ 85719 (United States); Gutermuth, Rob [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Juhasz, Attila [Leiden Observatory, Leiden University, Niels Bohrweg 2, NL-2333-CA Leiden (Netherlands); Bally, John [CASA, University of Colorado, CB 389, Boulder, CO 80309 (United States); Marton, Gabor, E-mail: balog@mpia.de [Konkoly Observatory, Research Center for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege 15-17, 1121 Budapest (Hungary)

    2014-07-10

    We report Herschel/Photodetector Array Camera and Spectrometer (PACS) photometric observations at 70 μm and 160 μm of LRLL54361—a suspected binary protostar that exhibits periodic (P = 25.34 days) flux variations at shorter wavelengths (3.6 μm and 4.5 μm) thought to be due to pulsed accretion caused by binary motion. The PACS observations show unprecedented flux variation at these far-infrared wavelengths that are well correlated with the variations at shorter wavelengths. At 70 μm the object increases its flux by a factor of six while at 160 μm the change is about a factor of two, consistent with the wavelength dependence seen in the far-infrared spectra. The source is marginally resolved at 70 μm with varying FWHM. Deconvolved images of the sources show elongations exactly matching the outflow cavities traced by the scattered light observations. The spatial variations are anti-correlated with the flux variation, indicating that a light echo is responsible for the changes in FWHM. The observed far-infrared flux variability indicates that the disk and envelope of this source is periodically heated by the accretion pulses of the central source, and suggests that such long wavelength variability in general may provide a reasonable proxy for accretion variations in protostars.

  12. Archival storage solutions for PACS

    Science.gov (United States)

    Chunn, Timothy

    1997-05-01

    While they are many, one of the inhibitors to the wide spread diffusion of PACS systems has been robust, cost effective digital archive storage solutions. Moreover, an automated Nearline solution is key to a central, sharable data repository, enabling many applications such as PACS, telemedicine and teleradiology, and information warehousing and data mining for research such as patient outcome analysis. Selecting the right solution depends on a number of factors: capacity requirements, write and retrieval performance requirements, scaleability in capacity and performance, configuration architecture and flexibility, subsystem availability and reliability, security requirements, system cost, achievable benefits and cost savings, investment protection, strategic fit and more.This paper addresses many of these issues. It compares and positions optical disk and magnetic tape technologies, which are the predominant archive mediums today. Price and performance comparisons will be made at different archive capacities, plus the effect of file size on storage system throughput will be analyzed. The concept of automated migration of images from high performance, high cost storage devices to high capacity, low cost storage devices will be introduced as a viable way to minimize overall storage costs for an archive. The concept of access density will also be introduced and applied to the selection of the most cost effective archive solution.

  13. Design and Implementation of PACS at Georgetown University Hospital

    Science.gov (United States)

    Mun, S. K.; Benson, H.. R.; Choyke, P.; Fahey, F. H.; Wang, P. C.; Zeman, R. K...; Elliott, L. P.

    1985-09-01

    During the preparation and planning phase of the PACS project at Georgetown University Hospital it was realized that PACS requires truly the state of the art technology in data communication, image processing and man machine interfacing. It was also realized that un-like many other technology intensive devices used in radiology, PACS cannot be seen as an independent system that will provide well defined services. PACS will be the backbone of the department operation in clinical, educational and managerial functions. It will indeed be the nerve center of the radiologic services affecting every aspect of the department. PACS will have to be designed to perform in a cost-effective manner to widely varying needs within the radiology departments. The integration of ever changing complex technology that will impact every aspect of a radiology service is not a trivial matter. This transition period going from current manual film based PACS to Digital PACS can be long, expansive and disruptive unless careful planning preceeds the implementation. PACS is still an emerging technology at its infancy. Performance monitoring and evaluation of diversified functions have to be also established so that improvement to the system can be efficiently implemented. Thus the evaluation criteria should be also established as early as possible.

  14. The effect of photometric and geometric context on photometric and geometric lightness effects.

    Science.gov (United States)

    Lee, Thomas Y; Brainard, David H

    2014-01-24

    We measured the lightness of probe tabs embedded at different orientations in various contextual images presented on a computer-controlled stereo display. Two background context planes met along a horizontal roof-like ridge. Each plane was a graphic rendering of a set of achromatic surfaces with the simulated illumination for each plane controlled independently. Photometric context was varied by changing the difference in simulated illumination intensity between the two background planes. Geometric context was varied by changing the angle between them. We parsed the data into separate photometric effects and geometric effects. For fixed geometry, varying photometric context led to linear changes in both the photometric and geometric effects. Varying geometric context did not produce a statistically reliable change in either the photometric or geometric effects.

  15. Photometric stereo endoscopy.

    Science.gov (United States)

    Parot, Vicente; Lim, Daryl; González, Germán; Traverso, Giovanni; Nishioka, Norman S; Vakoc, Benjamin J; Durr, Nicholas J

    2013-07-01

    While color video endoscopy has enabled wide-field examination of the gastrointestinal tract, it often misses or incorrectly classifies lesions. Many of these missed lesions exhibit characteristic three-dimensional surface topographies. An endoscopic system that adds topographical measurements to conventional color imagery could therefore increase lesion detection and improve classification accuracy. We introduce photometric stereo endoscopy (PSE), a technique which allows high spatial frequency components of surface topography to be acquired simultaneously with conventional two-dimensional color imagery. We implement this technique in an endoscopic form factor and demonstrate that it can acquire the topography of small features with complex geometries and heterogeneous optical properties. PSE imaging of ex vivo human gastrointestinal tissue shows that surface topography measurements enable differentiation of abnormal shapes from surrounding normal tissue. Together, these results confirm that the topographical measurements can be obtained with relatively simple hardware in an endoscopic form factor, and suggest the potential of PSE to improve lesion detection and classification in gastrointestinal imaging.

  16. ACS Photometric Zero Point Verification

    Science.gov (United States)

    Dolphin, Andrew

    2003-07-01

    The uncertainties in the photometric zero points create a fundamental limit to the accuracy of photometry. The current state of the ACS calibration is surprisingly poor, with zero point uncertainties of 0.03 magnitudes in the Johnson filters. The reason for this is that ACS observations of excellent ground-based standard fields, such as the omega Cen field used for WFPC2 calibrations, have not been obtained. Instead, the ACS photometric calibrations are based primarily on semi-emprical synthetic zero points and observations of fields too crowded for accurate ground-based photometry. I propose to remedy this problem by obtaining ACS broadband images of the omega Cen standard field with both the WFC and HRC. This will permit the direct determination of the ACS transformations, and is expected to double the accuracy to which the ACS zero points are known. A second benefit is that it will facilitate the comparison of the WFPC2 and ACS photometric systems, which will be important as WFPC2 is phased out and ACS becomes HST's primary imager.

  17. Cassini revisited by the Cassini-Huygens probe: dynamical and photometric study of the rings with the ISS images

    International Nuclear Information System (INIS)

    Deau, Estelle

    2007-12-01

    In the Solar system, the planetary rings represent a fantastic opportunity of studying a majority of phenomena taking place in the thin discs. One can find discs at all redshifts and on all scales of the Universe. Planetary discs are very different: among the Jovian rings, one finds a halo of fine and diffuse dust; the rings of Uranus are very compact, like radially confined strings and the system of rings of Neptune consists of azimuthally stable arcs. However our interest goes on Saturn which has the most complex and widest system of rings known to date: 484 000 km and a vertical extension which increases with the distance to Saturn (typically less than 1 km to 10 000 km). The interest of such a matter organization around Saturn plus its many moons (more than one forty including 8 of a size of several hundreds kilometers) gave birth to the exploration mission CASSINI, supposed to allow the development and the refinement of models set up at the flybies of the two interplanetary probes VOYAGER. The CASSINI Mission began its nominal tour on January, 15 2005 after the orbital insertion the 1 July 2004 and the dropping of HUYGENS probe on january, 14 2005 on Titan's surface. The purpose of this thesis consists to revisit two subjects unsolved of long date in the photometric and dynamic behaviours of the Saturn's rings. In a first part, we try to solve the problem of accretion of matter within the Roche limit by studying the F ring. This ring, since its discovery in 1979 by Pioneer 11, is involved in a most various dynamic theories to explain its complex multi-radial structure and its variable azimuthal structure. We showed that the multi-radial structure of this ring can be understood by the existence of a spiral which is rolled up around a central area, bright, eccentric and inclined: the core. The lifespan of this spiral is not the same one as the core, suggesting that the processes which create the spiral are periodic. Moreover, we showed that the structure of the

  18. IHE, Solution for integration of information systems and PACS

    Directory of Open Access Journals (Sweden)

    Milad Janghorban Lariche

    2014-10-01

    Full Text Available PACS is used as a way to store images and matches well with the workflow in the radiology department and can spread to other parts of hospital. Integration with other PACS and other hospital systems like radiology information system (RIS, hospital information system (HIS, and electronic patient records has been completely done, but there are still problems. PACS also provide good conditions for setting up Tele-radiology. The next step for PACS is where hospitals and health care organizations share photos in integrated electronic patient record. Among the different ways for sharing photos between different hospitals, IHE (integrating the health care enterprise standard indexes the cross-enterprise document sharing profile (XDS and allows sharing photos from various hospitals even if their PACS has different brands and different vendors. Application of XDS is useful for sharing images between health care organizations without duplicating them in a central archive. Images need to be indexed in a central registry. In the XDS profile, IHE defines an indexing mechanism for printing and indexing images in the central document registry. IHE also defines mechanisms to be used by each hospital to retrieve images, regardless of storing them in hospital PACS.

  19. Fine structure of Galactic foreground ISM towards high-redshift AGN - utilizing Herschel PACS and SPIRE data

    Science.gov (United States)

    Perger, K.; Pinter, S.; Frey, S.; Tóth, L. V.

    2018-05-01

    One of the most certain ways to determine star formation rate in galaxies is based on far infrared (FIR) measurements. To decide the origin of the observed FIR emission, subtracting the Galactic foreground is a crucial step. We utilized Herschel photometric data to determine the hydrogen column densities in three galactic latitude regions, at b = 27°, 50° and -80°. We applied a pixel-by-pixel fit to the spectral energy distribution (SED) for the images aquired from parallel PACS-SPIRE observations in all three sky areas. We determined the column densities with resolutions 45'' and 6', and compared the results with values estimated from the IRAS dust maps. Column densities at 27° and 50° galactic latitudes determined from the Herschel data are in a good agreement with the literature values. However, at the highest galactic latitude we found that the column densities from the Herschel data exceed those derived from the IRAS dust map.

  20. A DICOM based PACS for nuclear medicine; Ein DICOM-basiertes PACS fuer die Nuklearmedizin

    Energy Technology Data Exchange (ETDEWEB)

    Lassmann, M.; Reiners, C. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    2002-02-01

    The installation of a radiology information system (RIS) connected to a hospital information system (HIS) and a picture archiving and communications system (PACS) seems mandatory for a nuclear medicine department in order to guarantee a high patient throughput. With these systems a fast transmission of reports, images to the in- and out-patients' wards and private practitioners is realized. Therefore, since April 2000, at the department of nuclear medicine of the university of Wuerzburg a completely DICOM based PACS has been implemented in addition to the RIS. With this system a DICOM based workflow is realized throughout the department of nuclear medicine for reporting and archiving. The PACS is connected to six gamma-cameras, a PET scanner, a bone densitometry system and an ultrasound device. The volume of image data archived per month is 4 GByte. Patient demographics are provided to the modalities via DICOM-Worklist. With these PACS components a department specific archive purely based on DICOM can be realized. During the installation process problems occurred mainly because of the complex DICOM standard for nuclear medicine. Related to that is the problem that most of the software implementations still contain bugs or are not adapted to the needs of a nuclear medicine department (particularly for PET). A communication software for the distribution of nuclear medicine reports and images based on techniques used for the worldwide web is currently tested. (orig.) [German] Fuer eine nuklearmedizinische Klinik ist ein Klinikinformationssystem (KIS) gekoppelt mit einem Radiologieinformationssystem (RIS) sowie einem Bildarchivierungs- und Verteilungssystem (PACS) unabdingbar, um einen schnellen Patientendurchsatz sowie die zeitnahe Uebermittlung von Befunden inklusive nuklearmedizinischen Bildern an zuweisende Stationen, Ambulanzen und externe Zuweiser zu gewaehrleisten. Daher wurde im April 2000 an der Klinik und Poliklinik fuer Nuklearmedizin der Universitaet

  1. The many flavours of photometric redshifts

    Science.gov (United States)

    Salvato, Mara; Ilbert, Olivier; Hoyle, Ben

    2018-06-01

    Since more than 70 years ago, the colours of galaxies derived from flux measurements at different wavelengths have been used to estimate their cosmological distances. Such distance measurements, called photometric redshifts, are necessary for many scientific projects, ranging from investigations of the formation and evolution of galaxies and active galactic nuclei to precision cosmology. The primary benefit of photometric redshifts is that distance estimates can be obtained relatively cheaply for all sources detected in photometric images. The drawback is that these cheap estimates have low precision compared with resource-expensive spectroscopic ones. The methodology for estimating redshifts has been through several revolutions in recent decades, triggered by increasingly stringent requirements on the photometric redshift accuracy. Here, we review the various techniques for obtaining photometric redshifts, from template-fitting to machine learning and hybrid schemes. We also describe state-of-the-art results on current extragalactic samples and explain how survey strategy choices affect redshift accuracy. We close with a description of the photometric redshift efforts planned for upcoming wide-field surveys, which will collect data on billions of galaxies, aiming to investigate, among other matters, the stellar mass assembly and the nature of dark energy.

  2. PAC Experiments at ISOLDE

    CERN Multimedia

    2002-01-01

    The study of hyperfine interactions offers the possibility to use radioactive nuclei as probes in matter. The @g-@g perturbated angular correlation (PAC) technique following implantation has found widespread application in this field. At ISOLDE we have been investigating electric field gradients at impurities in non-cubic metals in an ongoing series of experiments. \\\\ \\\\ The small number of probe atoms necessary for these measurements make them also ideally suited for studies of surface problems like diffusion, structure and dynamics. Cd on a molybdenum O110? surface will be studied as first system. For this purpose 10|1|0~atoms of |1|1|1|mCd will be evaporated onto the clean surface and the electric field gradient for isolated adatoms on terrace sites will be determined by PAC. The UHV system constructed for such experiments at ISOLDE is shown in the schematic drawing. It is coupled to the beam line through differential pumping stations and contains standard surface treatment and analysis equipment.

  3. Acquisition and analysis of throughput rates for an operational department-wide PACS

    Science.gov (United States)

    Stewart, Brent K.; Taira, Ricky K.; Dwyer, Samuel J., III; Huang, H. K.

    1992-07-01

    The accurate prediction of image throughput is a critical issue in planning for and acquisition of any successful Picture Archiving and Communication System (PACS). Bottlenecks or design flaws can render an expensive PACS implementation useless. This manuscript presents a method for accurately predicting and measuring image throughput of a PACS design. To create the simulation model of the planned or implemented PACS, it must first be decomposed into principal tasks. We have decomposed the entire PACS image management chain into eight subsystems. These subsystems include network transfers over three different networks (Ethernet, FDDI and UltraNet) and five software programs and/or queues: (1) transfer of image data from the imaging modality computer to the image acquisition/reformatting computer; (2) reformatting the image data into a standard image format; (3) transferring the image data from the acquisition/reformatting computer to the image archive computer; (4) updating a relational database management system over the network; (5) image processing-- rotation and optimal gray-scale lookup table calculation; (6) request that the image be archived; (7) image transfer from the image archive computer to a designated image display workstation; and (8) update the local database on the image display station, separate the image header from the image data and store the image data on a parallel disk array. Through development of an event logging facility and implementation of a network management package we have acquired throughput data for each subsystem in the PACS chain. In addition, from our PACS relational database management system, we have distilled the traffic generation patterns (temporal, file size and destination) of our imaging modality devices. This data has been input into a simulation modeling package (Block Oriented Network Simulator-- BONeS) to estimate the characteristics of the modeled PACS, e.g., the throughput rates and delay time. This simulation

  4. Why PACS is no longer a four-letter word.

    Science.gov (United States)

    Chopra, R M

    2000-01-01

    The real value of PACS is not realized until widespread adoption exists among physicians other than interpreting radiologists. Referring physicians at the office level, in the operating room and in other departments must be willing to embrace the reading of images on monitors. That takes time. The payoff for a PACS system is therefore not realized until sometime in the future. Given the huge up-front capital expenditure required of PACS solutions, it is no wonder that the decision has historically been a difficult one to make. Enter the application service provider (ASP). The marriage of the ASP model to PACS seems to be one of the true "killer apps" currently available in the healthcare technology space. An ASP can host and maintain the software inherent in PACS solutions. Images are centrally archived over the short-, medium-, and long-term timeframe, utilizing state-of-art data management facilities. Some ASPs also provide the necessary bandwidth to office sites and the small amount of hardware that is required onsite, such as viewing stations or monitors. Costs for Internet-based image management under the ASP model rely on a pay-as-you-go formula, which may include all software, support, required hardware and bandwidth as part of the service. There may be a minor up-front fee for installation. The ASP pricing model eliminates the huge gamble an organization takes on "big iron" PACS purchases. Those benefits rely on the first rule of finance: a dollar today is worth more than a dollar tomorrow. PACS and ASPs were made for one another. Because the financial benefits of PACS are realized over time, the timing of cash flows is extremely important. Other benefits inherent in the ASP model such as scalability, diminished need for IT personnel, software version integrity and better pricing because of economies of scale are attractive also.

  5. Photometric estimation of defect size in radiation direction

    International Nuclear Information System (INIS)

    Zuev, V.M.

    1993-01-01

    Factors, affecting accuracy of photometric estimation of defect size in radiation transmission direction, are analyzed. Experimentally obtained dependences of contrast of defect image on its size in radiation transmission direction are presented. Practical recommendations on improving accuracy of photometric estimation of defect size in radiation transmission direction, are developed

  6. Investment alternative: the status quo or PACS?

    Science.gov (United States)

    Vanden Brink, John A.; Cywinski, Jozef K.

    1990-08-01

    While the cost of Picture Archiving and Communication Systems (PACS) can be substantial, the cost of continuing with present manual methods may become prohibitive in growing departments as the need for additional space and personnel (both technical and professional) to meet the increasing requirements for all image management activities continues to grow. This will occur simultaneously with increasing pressures on problems of the present system, i.e., lost films, lost revenues, delayed reporting and longer diagnostic cycle times. Present methods of image archiving communication and management i.e. the relationship of procedure volume to VFE requirements for professional and technical personnel, costs of film, film storage space, and other performance factors are analyzed based on the database created by the Technology Marketing Group (TMG) computerized cost analysis model applied to over 50 US hospitals. Also, the model is used to provide the projected cost of present methods of film management for an average US 400 +bed hospital based on ten year growth rate assumptions. TMG PACS Tracking data provides confirmation of staffmg pattern correlation to procedure volume. The data presented in the paper provides a basis for comparing the investment in maintaining the status quo to an investment in PACS.

  7. THE ALHAMBRA PHOTOMETRIC SYSTEM

    International Nuclear Information System (INIS)

    Villegas, T. Aparicio; Alfaro, E. J.; Cabrera-Cano, J.

    2010-01-01

    This paper presents the characterization of the optical range of the ALHAMBRA photometric system, a 20 contiguous, equal-width, medium-band CCD system with wavelength coverage from 3500 A to 9700 A. The photometric description of the system is done by presenting the full response curve as a product of the filters, CCD, and atmospheric transmission curves, and using some first- and second-order moments of this response function. We also introduce the set of standard stars that defines the system, formed by 31 classic spectrophotometric standard stars which have been used in the calibration of other known photometric systems, and 288 stars, flux calibrated homogeneously, from the Next Generation Spectral Library (NGSL). Based on the NGSL, we determine the transformation equations between Sloan Digital Sky Survey ugriz photometry and the ALHAMBRA photometric system, in order to establish some relations between both systems. Finally, we develop and discuss a strategy to calculate the photometric zero points of the different pointings in the ALHAMBRA project.

  8. PACS: Do clinical users benefit from it as a training adjunct? | van ...

    African Journals Online (AJOL)

    Although a PACS relates specifically to the archiving and retrieval of radiological images and reports, it became clear from the feedback received from medical clinicians (who ... The advantages of PACS as a positive training adjunct were highlighted in the areas of multi-site viewing and consultation, the possibility of image ...

  9. History of PACS in Asia.

    Science.gov (United States)

    Inamura, Kiyonari; Kim, Jong Hyo

    2011-05-01

    First, history of PACS (picture archiving and communication system for medical use) in Japan is described in two parts: in part 1, the early stage of PACS development from 1984 to 2002, and in part 2 the matured stage from 2002 to 2010. PACS in Japan has been developed and installed by local manufacturers by their own technology and demand from domestic hospitals. Part 1 mainly focuses on quantitative growth and part 2 on qualitative change. In part 2, integration of PACS into RIS (radiology information system), HIS (hospital information system), EPR (electronic patient record), teleradiology and IHE (integrating healthcare enterprise) is reported. Interaction with other elements of technology such as moving picture network system and three dimensional display is also discussed. Present situation of main 4 large size hospitals is presented. Second, history of PACS in Korea is reported. Very acute climbing up of filmless PACS diffusion was observed from 1997 to 2000. The reasons for such evolution are described and discussed. Also changes of PACS installation and system integration with other systems such as HIS and role of them in radiological diagnoses in Korea since 2002 are described. Third, history in China is investigated by checking international academic journals in English and described as far as events are logically linked and consistently meaningful. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  10. History of PACS in Asia

    International Nuclear Information System (INIS)

    Inamura, Kiyonari; Kim, Jong Hyo

    2011-01-01

    First, history of PACS (picture archiving and communication system for medical use) in Japan is described in two parts: in part 1, the early stage of PACS development from 1984 to 2002, and in part 2 the matured stage from 2002 to 2010. PACS in Japan has been developed and installed by local manufacturers by their own technology and demand from domestic hospitals. Part 1 mainly focuses on quantitative growth and part 2 on qualitative change. In part 2, integration of PACS into RIS (radiology information system), HIS (hospital information system), EPR (electronic patient record), teleradiology and IHE (integrating healthcare enterprise) is reported. Interaction with other elements of technology such as moving picture network system and three dimensional display is also discussed. Present situation of main 4 large size hospitals is presented. Second, history of PACS in Korea is reported. Very acute climbing up of filmless PACS diffusion was observed from 1997 to 2000. The reasons for such evolution are described and discussed. Also changes of PACS installation and system integration with other systems such as HIS and role of them in radiological diagnoses in Korea since 2002 are described. Third, history in China is investigated by checking international academic journals in English and described as far as events are logically linked and consistently meaningful.

  11. The Dependence of Signal-To-Noise Ratio (S/N) Between Star Brightness and Background on the Filter Used in Images Taken by the Vulcan Photometric Planet Search Camera

    Science.gov (United States)

    Mena-Werth, Jose

    1998-01-01

    The Vulcan Photometric Planet Search is the ground-based counterpart of Kepler Mission Proposal. The Kepler Proposal calls for the launch of telescope to look intently at a small patch of sky for four year. The mission is designed to look for extra-solar planets that transit sun-like stars. The Kepler Mission should be able to detect Earth-size planets. This goal requires an instrument and software capable of detecting photometric changes of several parts per hundred thousand in the flux of a star. The goal also requires the continuous monitoring of about a hundred thousand stars. The Kepler Mission is a NASA Discovery Class proposal similar in cost to the Lunar Prospector. The Vulcan Search is also a NASA project but based at Lick Observatory. A small wide-field telescope monitors various star fields successively during the year. Dozens of images, each containing tens of thousands of stars, are taken any night that weather permits. The images are then monitored for photometric changes of the order of one part in a thousand. These changes would reveal the transit of an inner-orbit Jupiter-size planet similar to those discovered recently in spectroscopic searches. In order to achieve a one part in one thousand photometric precision even the choice of a filter used in taking an exposure can be critical. The ultimate purpose of an filter is to increase the signal-to-noise ratio (S/N) of one's observation. Ideally, filters reduce the sky glow cause by street lights and, thereby, make the star images more distinct. The higher the S/N, the higher is the chance to observe a transit signal that indicates the presence of a new planet. It is, therefore, important to select the filter that maximizes the S/N.

  12. PACS-Based Computer-Aided Detection and Diagnosis

    Science.gov (United States)

    Huang, H. K. (Bernie); Liu, Brent J.; Le, Anh HongTu; Documet, Jorge

    The ultimate goal of Picture Archiving and Communication System (PACS)-based Computer-Aided Detection and Diagnosis (CAD) is to integrate CAD results into daily clinical practice so that it becomes a second reader to aid the radiologist's diagnosis. Integration of CAD and Hospital Information System (HIS), Radiology Information System (RIS) or PACS requires certain basic ingredients from Health Level 7 (HL7) standard for textual data, Digital Imaging and Communications in Medicine (DICOM) standard for images, and Integrating the Healthcare Enterprise (IHE) workflow profiles in order to comply with the Health Insurance Portability and Accountability Act (HIPAA) requirements to be a healthcare information system. Among the DICOM standards and IHE workflow profiles, DICOM Structured Reporting (DICOM-SR); and IHE Key Image Note (KIN), Simple Image and Numeric Report (SINR) and Post-processing Work Flow (PWF) are utilized in CAD-HIS/RIS/PACS integration. These topics with examples are presented in this chapter.

  13. Photometric Lunar Surface Reconstruction

    Science.gov (United States)

    Nefian, Ara V.; Alexandrov, Oleg; Morattlo, Zachary; Kim, Taemin; Beyer, Ross A.

    2013-01-01

    Accurate photometric reconstruction of the Lunar surface is important in the context of upcoming NASA robotic missions to the Moon and in giving a more accurate understanding of the Lunar soil composition. This paper describes a novel approach for joint estimation of Lunar albedo, camera exposure time, and photometric parameters that utilizes an accurate Lunar-Lambertian reflectance model and previously derived Lunar topography of the area visualized during the Apollo missions. The method introduced here is used in creating the largest Lunar albedo map (16% of the Lunar surface) at the resolution of 10 meters/pixel.

  14. Fitting PAC spectra with stochastic models: PolyPacFit

    Energy Technology Data Exchange (ETDEWEB)

    Zacate, M. O., E-mail: zacatem1@nku.edu [Northern Kentucky University, Department of Physics and Geology (United States); Evenson, W. E. [Utah Valley University, College of Science and Health (United States); Newhouse, R.; Collins, G. S. [Washington State University, Department of Physics and Astronomy (United States)

    2010-04-15

    PolyPacFit is an advanced fitting program for time-differential perturbed angular correlation (PAC) spectroscopy. It incorporates stochastic models and provides robust options for customization of fits. Notable features of the program include platform independence and support for (1) fits to stochastic models of hyperfine interactions, (2) user-defined constraints among model parameters, (3) fits to multiple spectra simultaneously, and (4) any spin nuclear probe.

  15. Partners Against Crime (PAC) Districts

    Data.gov (United States)

    City and County of Durham, North Carolina — The Partners Against Crime (PAC) program promotes collaboration among police officers, Durham residents, and city and county government officials to find...

  16. A photometric study of Enceladus

    Science.gov (United States)

    Verbiscer, Anne J.; Veverka, Joseph

    1994-01-01

    We have supplemented Voyager imaging data from Enceladus (limited to phase angles of 13 deg-43 deg) with recent Earth-based CCD observations to obtain an improved determination of the Bond albedo, to construct an albedo map of the satellite, and to constrain parameters in Hapke's (1986) photometric equation. A major result is evidence of regional variations in the physical properties of Enceladus' surface. The average global photometric properties are described by single scattering albedo omega(sub 0) average = 0.998 +/- 0.001, macroscopic roughness parameter theta average = 6 +/- 1 deg, and Henyey-Greenstein asymmetry parameter g = -0.399 +/- 0.005. The value of theta average is smaller than the 14 deg found by fitting whole-disk data, which include all terrains on Enceladus. The opposition surge amplitude B(sub 0) = 0.21 +/- 0.07 and regolith compaction parameter h = 0.014 +/- 0.02 are loosely constrained by the scarcity of and uncertainty in near-opposition observations. From the solar phase curve we determine the geometric albedo of Enceladus p(sub v) = 0.99 +/- 0.06 and phase integral q = 0.92 +/- 0.05, which corresponds to a spherical albedo A = p(sub v)q = 0.91 +/- 0.1. Since the spectrum of Enceladus is fairly flat, we can approximate the Bond albedo A(sub B) with the spherical albedo. Our photometric analysis is summarized in terms of an albedo map which generally reproduces the satellite's observed lightcurve and indicates that normal reflectances range from 0.9 on the leading hemisphere to 1.4 on the trailing one. The albedo map also revels an albedo variation of 15% from longitudes 170 deg to 200 deg, corresponding to the boundary between the leading and trailing hemispheres.

  17. Astrometric vs. photometric microlensing

    NARCIS (Netherlands)

    Dominik, M; Brainerd, TG; Kochanek, CS

    2001-01-01

    I discuss the differences between the properties of astrometric and photometric microlensing and between the arising prospects for survey and follow-up experiments based on these two different signatures. In particular, the prospects for binary stars and extra-solar planets are considered.

  18. Bioavailability of {sup 99m}Tc-paclitaxel-glucuronide ({sup 99m}Tc-PAC-G)

    Energy Technology Data Exchange (ETDEWEB)

    Biber Muftuler, F.Z.; Demir, I.; Uenack, P.; Ichedef, C.; Yurt Kilcar, A. [Ege Univ., Izmir (Turkey). Dept. of Nuclear Applications

    2011-07-01

    An antitumor agent paclitaxel (PAC) has been proved to be efficient in the treatment of breast and ovarian cancer. Glucuronic acid-derived paclitaxel compound (paclitaxel-glucuronide (PAC-G)) was enzymatically synthesized using microsome preparate separated from rat livers. The biodistribution mechanism of PAC-G in healthy female Albino Wistar rats has been investigated. The expected structure is confirmed according to LC/MS results, and the possible attachment is to C2-hydroxyl group. PAC-G was labeled with {sup 99m}Tc and the radiochemical yield of radiolabeled compound ({sup 99m}Tc-PAC-G) was 98.0 {+-} 02.74% (n=9). The range of the breast/blood and breast/muscle ratios is approximately between 3 and 35 in 240 min. All these experimental studies indicate that {sup 99m}Tc-PAC-G may potentially be used in breast tissue as an imaging agent. (orig.)

  19. PACS in Töölö hospital.

    Science.gov (United States)

    Kinnunen, J; Pohjonen, H

    2001-07-01

    A 3-year PACS project was started in 1997 and completed in 1999 with filmless radiology and surgery. An efficient network for transferring images provides the infrastructure for integration of different distributed imaging systems and enables efficient handling of all patient-related information on one display station. Because of the need for high-speed communications and the massive amount of image data transferred in radiology, ATM (25, 155 Mbit/s) was chosen to be the main technology used. Both hardware and software redundancy of the system have been carefully planned. The size of the Dicom image library utilizing MO discs is currently 1.2 TB with 300 GB RAID capacity. For the increasing amount of teleradiologic consultations, a special Dicom gateway is planned. It allows a centralized and resilient handling and routing of received images around the hospital. Hospital-wide PACS has already improved the speed and quality of patient care by providing instant access to diagnostic information at multiple locations simultaneously. The benefits of PACS are considered from the viewpoint of the entire hospital: PACS offers a method for efficiently transporting patient-related images and reports to the referring physicians.

  20. PACS 2000: quality control using the task allocation chart

    Science.gov (United States)

    Norton, Gary S.; Romlein, John R.; Lyche, David K.; Richardson, Ronald R., Jr.

    2000-05-01

    Medical imaging's technological evolution in the next century will continue to include Picture Archive and Communication Systems (PACS) and teleradiology. It is difficult to predict radiology's future in the new millennium with both computed radiography and direct digital capture competing as the primary image acquisition methods for routine radiography. Changes in Computed Axial Tomography (CT) and Magnetic Resonance Imaging (MRI) continue to amaze the healthcare community. No matter how the acquisition, display, and archive functions change, Quality Control (QC) of the radiographic imaging chain will remain an important step in the imaging process. The Task Allocation Chart (TAC) is a tool that can be used in a medical facility's QC process to indicate the testing responsibilities of the image stakeholders and the medical informatics department. The TAC shows a grid of equipment to be serviced, tasks to be performed, and the organization assigned to perform each task. Additionally, skills, tasks, time, and references for each task can be provided. QC of the PACS must be stressed as a primary element of a PACS' implementation. The TAC can be used to clarify responsibilities during warranty and paid maintenance periods. Establishing a TAC a part of a PACS implementation has a positive affect on patient care and clinical acceptance.

  1. Altered circadian food anticipatory activity rhythms in PACAP receptor 1 (PAC1) deficient mice

    DEFF Research Database (Denmark)

    Hannibal, Jens; Georg, Birgitte; Fahrenkrug, Jan

    2016-01-01

    increase in amplitude compared to PAC1+/+ mice when placed in SPP at 300 lux. The same pattern of FAA was observed at 10 lux during both FPP and SPP. The present study indicates a role of PACAP/PAC1 signaling during light regulated FAA. Most likely, PACAP found in ipRGCs mediating non-image forming light...

  2. Integration of computer-aided diagnosis/detection (CAD) results in a PACS environment using CAD-PACS toolkit and DICOM SR

    International Nuclear Information System (INIS)

    Le, Anh H.T.; Liu, Brent; Huang, H.K.

    2009-01-01

    Picture Archiving and Communication System (PACS) is a mature technology in health care delivery for daily clinical imaging service and data management. Computer-aided detection and diagnosis (CAD) utilizes computer methods to obtain quantitative measurements from medical images and clinical information to assist clinicians to assess a patient's clinical state more objectively. CAD needs image input and related information from PACS to improve its accuracy; and PACS benefits from CAD results online and available at the PACS workstation as a second reader to assist physicians in the decision making process. Currently, these two technologies remain as two separate independent systems with only minimal system integration. This paper describes a universal method to integrate CAD results with PACS in its daily clinical environment. The method is based on Health Level 7 (HL7) and Digital imaging and communications in medicine (DICOM) standards, and Integrating the Healthcare Enterprise (IHE) workflow profiles. In addition, the integration method is Health Insurance Portability and Accountability Act (HIPAA) compliant. The paper presents (1) the clinical value and advantages of integrating CAD results in a PACS environment, (2) DICOM Structured Reporting formats and some important IHE workflow profiles utilized in the system integration, (3) the methodology using the CAD-PACS integration toolkit, and (4) clinical examples with step-by-step workflows of this integration. (orig.)

  3. A PACS archive architecture supported on cloud services.

    Science.gov (United States)

    Silva, Luís A Bastião; Costa, Carlos; Oliveira, José Luis

    2012-05-01

    Diagnostic imaging procedures have continuously increased over the last decade and this trend may continue in coming years, creating a great impact on storage and retrieval capabilities of current PACS. Moreover, many smaller centers do not have financial resources or requirements that justify the acquisition of a traditional infrastructure. Alternative solutions, such as cloud computing, may help address this emerging need. A tremendous amount of ubiquitous computational power, such as that provided by Google and Amazon, are used every day as a normal commodity. Taking advantage of this new paradigm, an architecture for a Cloud-based PACS archive that provides data privacy, integrity, and availability is proposed. The solution is independent from the cloud provider and the core modules were successfully instantiated in examples of two cloud computing providers. Operational metrics for several medical imaging modalities were tabulated and compared for Google Storage, Amazon S3, and LAN PACS. A PACS-as-a-Service archive that provides storage of medical studies using the Cloud was developed. The results show that the solution is robust and that it is possible to store, query, and retrieve all desired studies in a similar way as in a local PACS approach. Cloud computing is an emerging solution that promises high scalability of infrastructures, software, and applications, according to a "pay-as-you-go" business model. The presented architecture uses the cloud to setup medical data repositories and can have a significant impact on healthcare institutions by reducing IT infrastructures.

  4. Clinical experience with PACS at Northwestern: year two

    Science.gov (United States)

    Channin, David S.; Hawkins, Rodney C.; Enzmann, Dieter R.

    2001-08-01

    We have previously described the PACS configuration at Northwestern Memorial Hospital (NMH). As opposed to an imaging modality, PACS is an evolving system that continuously grows and changes to meet the needs of the institution. The NMH PACS has grown significantly in the past year and has undergone significant architectural enhancements. This growth and evolutionary change will be described and discussed. The system now contains over 339,000 studies consisting of over 13 million images. There are now two short-term RAID storage units that provide for twice as much fast storage. There are also two magneto-optical disk jukeboxes providing long-term archive. We have deployed a redundant database to improve reliability of the system in the event of database failure. The number of modalities connected to the system has increased and will be summarized. Statistics describing utilization of the PACS will be shown. Lastly, we will discuss our plans for exploiting the application service provider model in our PACS environment.

  5. Photometric microdetermination of malathion

    Science.gov (United States)

    Kallman, B.J.

    1962-01-01

    Carboxylic esters and lactones react with alkaline hydroxylamine to yield hydroxamates; these in acidic solution form colored iron(III) complexes. A photometric determination of such esters and lactones is thus permitted and has been extensively applied ( I-6). Hestrin ( 3) utilized this method for the microdetermination of acetylcholine and his procedure is much used for the in vitro study of cholinesterase activity and inhibition (4-6).

  6. Photometric diversity of terrains on Triton

    Science.gov (United States)

    Hillier, J.; Veverka, J.; Helfenstein, P.; Lee, P.

    1994-01-01

    Voyager disk-resolved images of Triton in the violet (0.41 micrometers) and green (0.56 micrometer wavelengths have been analyzed to derive the photometric characteristics of terrains on Triton. Similar conclusions are found using two distinct but related definitions of photometric units, one based on color ratio and albedo properties (A. S. McEwen, 1990), the other on albedo and brightness ratios at different phase angles (P. Lee et al., 1992). A significant diversity of photometric behavior, much broader than that discovered so far on any other icy satellite, occurs among Triton's terrains. Remarkably, differences in photometric behavior do not correlate well with geologic terrain boundaries defined on the basis of surface morphology. This suggests that in most cases photometric properties on Triton are controlled by thin deposits superposed on underlying geologic units. Single scattering albedos are 0.98 or higher and asymmetry factors range from -0.35 to -0.45 for most units. The most distinct scattering behavior is exhibited by the reddish northern units already identified as the Anomalously Scattering Region (ASR), which scatters light almost isotropically with g = -0.04. In part due to the effects of Triton's clouds and haze, it is difficult to constrain the value of bar-theta, Hapke's macroscopic roughness parameter, precisely for Triton or to map differences in bar-theta among the different photometric terrains. However, our study shows that Triton must be relatively smooth, with bar-theta less than 15-20 degs and suggests that a value of 14 degs is appropriate. The differences in photometric characteristics lead to significantly different phase angle behavior for the various terrains. For example, a terrain (e.g., the ASR) that appears dark relative to another at low phase angles will reverse its contrast (become relatively brighter) at larger phase angles. The photometric parameters have been used to calculate hemispherical albedos for the units and to

  7. PCaPAC 2006 Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov; Matthew Bickley (Eds.)

    2007-03-30

    The 6-th international PCaPAC (Personal Computers and Particle Accelerator Controls) workshop was held at Jefferson Lab, Newport News, Virginia, from October 24-27, 2006. The main objectives of the conference were to discuss the most important issues of the use of PCs and modern IT technologies for controls of accelerators and to give scientists, engineers, and technicians a forum to exchange the ideas on control problems and their solutions. The workshop consisted of plenary sessions and poster sessions. No parallel sessions were held.Totally, more than seventy oral and poster presentations as well as tutorials were made during the conference, on the basis of which about fifty papers were submitted by the authors and included in this publication. This printed version of the PCaPAC 2006 Proceedings is published at Jefferson Lab according to the decision of the PCaPAC International Program Committee of October 26, 2006.

  8. Secure vendor environment (SVE) for PACS

    Science.gov (United States)

    Honeyman-Buck, Janice; Frost, Meryll

    2005-04-01

    vendors of image producing modalities such as CT, MRI, and CR typically do not protect their equipment from network intrusion. Most vendors use the same user-ids and passwords for their service and administrative accounts which makes it easy for them to get to their systems for remote repairs and upgrades, but also makes it easy for hackers and other unwelcome intruders to gain access. We use a device with two network interface cards to isolate the vendor network from the main PACS / university / hospital network. This device is a store and forward PACS routing device, a DICOM repair device, a modality worklist proxy device, and a de-facto firewall. This device is named an Application Processor (AP). In addition, a small virtual private network (VPN) device is placed on the system that can be controlled only by the PACS administration. If a vendor engineer needs remote access to upgrade or service the equipment, a temporary connection is enabled for only the computer the engineer is using at the time, then is closed when he/she has completed their work. Results: The secure vendor environment (SVE) consists of a computer and a VPN appliance and costs approximately 2,000 USD to build. With software, the total system costs approximately 2800 - $3500. The SVE is typically deployed as part of every equipment installation. Since the SVE has been used, we have had no intrusion and no downtime due to hackers, viruses, worms, etc. This is now a part of every project plan for equipment that will become part of the PACS. New work: The SVE is a unique and new work by our group, developed as a solution totally within our group. Conclusions: Our results have convinced our administration that this small cost to protect vendor equipment is well worth the investment. Prior to developing this solution, there were numerous occasions where intruders invaded our equipment and rendered it unusable until the software could be reloaded, sometimes resulting in the loss of a day or more of

  9. XDS-I Gateway Development for HIE Connectivity with Legacy PACS at Gil Hospital.

    Science.gov (United States)

    Simalango, Mikael Fernandus; Kim, Youngchul; Seo, Young Tae; Choi, Young Hwan; Cho, Yong Kyun

    2013-12-01

    The ability to support healthcare document sharing is imperative in a health information exchange (HIE). Sharing imaging documents or images, however, can be challenging, especially when they are stored in a picture archiving and communication system (PACS) archive that does not support document sharing via standard HIE protocols. This research proposes a standard-compliant imaging gateway that enables connectivity between a legacy PACS and the entire HIE. Investigation of the PACS solutions used at Gil Hospital was conducted. An imaging gateway application was then developed using a Java technology stack. Imaging document sharing capability enabled by the gateway was tested by integrating it into Gil Hospital's order communication system and its HIE infrastructure. The gateway can acquire radiology images from a PACS storage system, provide and register the images to Gil Hospital's HIE for document sharing purposes, and make the images retrievable by a cross-enterprise document sharing document viewer. Development of an imaging gateway that mediates communication between a PACS and an HIE can be considered a viable option when the PACS does not support the standard protocol for cross-enterprise document sharing for imaging. Furthermore, the availability of common HIE standards expedites the development and integration of the imaging gateway with an HIE.

  10. PACS or the future of the radiologist's working place

    International Nuclear Information System (INIS)

    Meyer-Ebrecht, D.

    1988-01-01

    PACS (picture archiving and communication systems) is a synonym for the replacement of the traditional photographic film by means of technologies that will communicate and store images exclusively in digital form. Digital mass storage will replace the film archives and will be linked to all image sources by means of a data communication network. More significantly, PACS will also introduce a novel type of image-evaluation modality, the diagnostic image work station. Images will be displayed on TV monitors. In addition, a variety of support functions will become available for image handling and processing. The replacement of the light box by a digital work station will definitely cause dramatic changes in the radiologist's work. (orig.) [de

  11. THE APPARATUS FOR ALIGNMENT OF THE PHOTOMETRIC LAMP FILAMENT

    Directory of Open Access Journals (Sweden)

    V. A. Dlugunovich

    2015-01-01

    Full Text Available During photometric measurements involving the use of photometric lamps it is necessary that the filament of lamp takes a strictly predetermined position with respect to the photodetector and the optical axis of the photometric setup. The errors in positioning of alignment filament with respect to the optical axis of the measuring system lead to increase the uncertainty of measurement of the photometric characteristics of the light sources. A typical method for alignment of filament of photometric lamps is based on the use a diopter tubes (telescopes. Using this method, the mounting of filament to the required position is carried out by successive approximations, which requires special concentration and a lot of time. The aim of this work is to develop an apparatus for alignment which allows simultaneous alignment of the filament of lamps in two mutually perpendicular planes. The method and apparatus for alignment of the photometric lamp filament during measurements of the photometric characteristics of light sources based on two digital video cameras is described in this paper. The apparatus allows to simultaneously displaying the image of lamps filament on the computer screen in two mutually perpendicular planes. The apparatus eliminates a large number of functional units requiring elementwise alignment and reduces the time required to carry out the alignment. The apparatus also provides the imaging of lamps filament with opaque coated on the bulb. The apparatus is used at the National standard of light intensity and illuminance units of the Republic of Belarus. 

  12. Photometric properties of Mars soils analogs

    Science.gov (United States)

    Pommerol, A.; Thomas, N.; Jost, B.; Beck, P.; Okubo, C.; McEwen, A.S.

    2013-01-01

    We have measured the bidirectional reflectance of analogs of dry, wet, and frozen Martian soils over a wide range of phase angles in the visible spectral range. All samples were produced from two geologic samples: the standard JSC Mars-1 soil simulant and Hawaiian basaltic sand. In a first step, experiments were conducted with the dry samples to investigate the effects of surface texture. Comparisons with results independently obtained by different teams with similar samples showed a satisfying reproducibility of the photometric measurements as well as a noticeable influence of surface textures resulting from different sample preparation procedures. In a second step, water was introduced to produce wet and frozen samples and their photometry investigated. Optical microscope images of the samples provided information about their microtexture. Liquid water, even in relatively low amount, resulted in the disappearance of the backscattering peak and the appearance of a forward-scattering peak whose intensity increases with the amount of water. Specular reflections only appeared when water was present in an amount large enough to allow water to form a film at the surface of the sample. Icy samples showed a wide variability of photometric properties depending on the physical properties of the water ice. We discuss the implications of these measurements in terms of the expected photometric behavior of the Martian surface, from equatorial to circum-polar regions. In particular, we propose some simple photometric criteria to improve the identification of wet and/or icy soils from multiple observations under different geometries.

  13. PACS project management utilizing web-based tools

    Science.gov (United States)

    Patel, Sunil; Levin, Brad; Gac, Robert J., Jr.; Harding, Douglas, Jr.; Chacko, Anna K.; Radvany, Martin; Romlein, John R.

    2000-05-01

    As Picture Archiving and Communications Systems (PACS) implementations become more widespread, the management of deploying large, multi-facility PACS will become a more frequent occurrence. The tools and usability of the World Wide Web to disseminate project management information obviates time, distance, participant availability, and data format constraints, allowing for the effective collection and dissemination of PACS planning, implementation information, for a potentially limitless number of concurrent PACS sites. This paper will speak to tools, such as (1) a topic specific discussion board, (2) a 'restricted' Intranet, within a 'project' Intranet. We will also discuss project specific methods currently in use in a leading edge, regional PACS implementation concerning the sharing of project schedules, physical drawings, images of implementations, site-specific data, point of contacts lists, project milestones, and a general project overview. The individual benefits realized for the end user from each tool will also be covered. These details will be presented, balanced with a spotlight on communication as a critical component of any project management undertaking. Using today's technology, the web arguably provides the most cost and resource effective vehicle to facilitate the broad based, interactive sharing of project information.

  14. Project plan for PACS networking construction and cabling

    International Nuclear Information System (INIS)

    Luo Min; Wang Xiaolin; Luo Song; Lei Wenyong; Wang Xuejian; Wen Hongyue; Wu Hongxing

    2002-01-01

    Objective: To meet the networking requirement of the heave data flow, load balance, and potential networking storm during expanding the application of PACS. Methods: Intel Net Structure 480T Giga Switch was used as main switch and connected to each building by optical channel at 1 Giga speed to archive 100 MB/s to each port. At the same time, the in dependence of the original networking construction was physically kept. The layer 3 and 4 switchers was used as load balance to reduce the heavy load of the networking, and all the cabling for PACS used the super CAT5 along with the Intel Net Structure 1520 to prepare for the potential networking storm. Results: An advanced intranet was set up to fully meet the high standard requirement of PACS. The good foundation for upgrading the whole networking system to 1 Giga application was built for realized share and transmission of image, information, and patient data within the hospital. The base was established for the standardized management of the hospital. Conclusion: Good planning is the 1 st step in setting up PACS and the equipment are the platform to run PACS and all kinds of HIS. The networking construction is the foundation of e-hospitals

  15. Performance characteristics of the Mayo/IBM PACS

    Science.gov (United States)

    Persons, Kenneth R.; Gehring, Dale G.; Pavicic, Mark J.; Ding, Yingjai

    1991-07-01

    The Mayo Clinic and IBM (at Rochester, Minnesota) have jointly developed a picture archiving system for use with Mayo's MRI and Neuro CT imaging modalities. The communications backbone of the PACS is a portion of the Mayo institutional network: a series of 4-Mbps token rings interconnected by bridges and fiber optic extensions. The performance characteristics of this system are important to understand because they affect the response time a PACS user can expect, and the response time for non-PACS users competing for resources on the institutional network. The performance characteristics of each component and the average load levels of the network were measured for various load distributions. These data were used to quantify the response characteristics of the existing system and to tune a model developed by North Dakota State University Department of Computer Science for predicting response times of more complex topologies.

  16. Does PACS improve diagnostic accuracy in chest radiograph interpretations in clinical practice?

    International Nuclear Information System (INIS)

    Hurlen, Petter; Borthne, Arne; Dahl, Fredrik A.; Østbye, Truls; Gulbrandsen, Pål

    2012-01-01

    Objectives: To assess the impact of a Picture Archiving and Communication System (PACS) on the diagnostic accuracy of the interpretation of chest radiology examinations in a “real life” radiology setting. Materials and methods: During a period before PACS was introduced to radiologists, when images were still interpreted on film and reported on paper, images and reports were also digitally stored in an image database. The same database was used after the PACS introduction. This provided a unique opportunity to conduct a blinded retrospective study, comparing sensitivity (the main outcome parameter) in the pre and post-PACS periods. We selected 56 digitally stored chest radiograph examinations that were originally read and reported on film, and 66 examinations that were read and reported on screen 2 years after the PACS introduction. Each examination was assigned a random number, and both reports and images were scored independently for pathological findings. The blinded retrospective score for the original reports were then compared with the score for the images (the gold standard). Results: Sensitivity was improved after the PACS introduction. When both certain and uncertain findings were included, this improvement was statistically significant. There were no other statistically significant changes. Conclusion: The result is consistent with prospective studies concluding that diagnostic accuracy is at least not reduced after PACS introduction. The sensitivity may even be improved.

  17. Current status and installation of dental PACS

    International Nuclear Information System (INIS)

    Park, Chang Seo; Kim, Kee Deog; Park, Hyok; Jeong, Ho Gul

    2004-01-01

    Picture Archiving and Communication System (PACS) is difficult to implement in the best of situations, but evidence is growing that the benefits are significant. The aims of this study are to analyze the current status of full PACS and establish successful installation standard of dental PACS. Materials and Methods were based on the investigation of current working status and installation standard of PACS, and observation of variable issues to installation of dental PACS. By September 30, 2004, full PACS implementations in their facilities were 88.1% in specialized general hospitals (37 installations out of total 42 hospitals), 59.8% in general hospitals (144 installations out of total 241 hospitals), 12.3% in medical hospitals (116 installations out of total 941 hospitals) and 3.6% in dental hospitals (4 installations out of total 110 hospitals). Only 4 university dental hospitals currently have installed and are operating full PACS. Major obstacle to wide spread of dental PACS is initial high investments. Clinical environments of dental PACS differed from medical situation. Because of characteristic dental practice, the initial investments for dental PACS are generally much greater than those of medical PACS. Also new economic crisis makes users scruple. The best way to overcome these limitations is to establish an economic installation standard for dental PACS. Also the clear technical communication between the customer and the supplier before both sides are committed to the obstacles are critical to its success.

  18. Medical Data Manager an Interface between PACS and the gLite Data Management System

    CERN Document Server

    Montagnat, Johan; Texier, Romain; Nienartowicz, Krzysztof; Baud, Jean-Philippe

    2008-01-01

    The medical imaging community uses the DICOM image format and protocol to store and exchange data. The Medical Data Manager (MDM) is an interface between DICOM compliant systems such as PACS and the EGEE Data Management System. It opens hospital imaging networks to the world scale Grid while protecting sensitive medical data. It can be accessed transparently from any gLite service. It is an important milestone towards adoption of Grid technologies in the medical imaging community. Hospitals continuously produce tremendous amounts of image data that is managed by local PACS (Picture Archiving and Communication Systems). These systems are often limited to a local network access although the community experiences a growing interest for data sharing and remote processing. Indeed, patient data is often spread out different medical data acquisition centers. Furthermore, researchers in the area often need to analyze large populations whose data can be gathered through federations of PACS. Opening PACS to the outer I...

  19. Is PACS feasible for a major department of radiology

    International Nuclear Information System (INIS)

    Bautz, W.; Kolbe, J.

    1986-01-01

    Picture Archiving and Communication Systems (PACS) are getting more and more important for Departments of Radiology with the increasing spread of digital imaging methods. To determine the demands made on such systems, we calculated the digital image data volume for all examinations carried out in 1983 at the Department of Medical Radiology of the University of Tuebingen. 20.37% of all examinations were performed with digitalised equipment. Plain radiography takes the lion's share among the total number of image data. If digitalisation is based on a spatial resolution of 8 Lp/mm, the share is 98.4% of the total image data volume of 7123 GByte. This figure is far in excess of the estimates stated in literature. The possibilities of image data reduction and feasibility of a major PACS are discussed. (orig.) [de

  20. Supernova Photometric Lightcurve Classification

    Science.gov (United States)

    Zaidi, Tayeb; Narayan, Gautham

    2016-01-01

    This is a preliminary report on photometric supernova classification. We first explore the properties of supernova light curves, and attempt to restructure the unevenly sampled and sparse data from assorted datasets to allow for processing and classification. The data was primarily drawn from the Dark Energy Survey (DES) simulated data, created for the Supernova Photometric Classification Challenge. This poster shows a method for producing a non-parametric representation of the light curve data, and applying a Random Forest classifier algorithm to distinguish between supernovae types. We examine the impact of Principal Component Analysis to reduce the dimensionality of the dataset, for future classification work. The classification code will be used in a stage of the ANTARES pipeline, created for use on the Large Synoptic Survey Telescope alert data and other wide-field surveys. The final figure-of-merit for the DES data in the r band was 60% for binary classification (Type I vs II).Zaidi was supported by the NOAO/KPNO Research Experiences for Undergraduates (REU) Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program (AST-1262829).

  1. Cardio-PACs: a new opportunity

    Science.gov (United States)

    Heupler, Frederick A., Jr.; Thomas, James D.; Blume, Hartwig R.; Cecil, Robert A.; Heisler, Mary

    2000-05-01

    It is now possible to replace film-based image management in the cardiac catheterization laboratory with a Cardiology Picture Archiving and Communication System (Cardio-PACS) based on digital imaging technology. The first step in the conversion process is installation of a digital image acquisition system that is capable of generating high-quality DICOM-compatible images. The next three steps, which are the subject of this presentation, involve image display, distribution, and storage. Clinical requirements and associated cost considerations for these three steps are listed below: Image display: (1) Image quality equal to film, with DICOM format, lossless compression, image processing, desktop PC-based with color monitor, and physician-friendly imaging software; (2) Performance specifications include: acquire 30 frames/sec; replay 15 frames/sec; access to file server 5 seconds, and to archive 5 minutes; (3) Compatibility of image file, transmission, and processing formats; (4) Image manipulation: brightness, contrast, gray scale, zoom, biplane display, and quantification; (5) User-friendly control of image review. Image distribution: (1) Standard IP-based network between cardiac catheterization laboratories, file server, long-term archive, review stations, and remote sites; (2) Non-proprietary formats; (3) Bidirectional distribution. Image storage: (1) CD-ROM vs disk vs tape; (2) Verification of data integrity; (3) User-designated storage capacity for catheterization laboratory, file server, long-term archive. Costs: (1) Image acquisition equipment, file server, long-term archive; (2) Network infrastructure; (3) Review stations and software; (4) Maintenance and administration; (5) Future upgrades and expansion; (6) Personnel.

  2. Toshiba General Hospital PACS for routine in- and outpatient clinics

    Science.gov (United States)

    Toshimitsu, Akihiro; Okazaki, Nobuo; Kura, Hiroyuki; Nishihara, Eitaro; Tsubura, Shinichi

    1996-05-01

    The Toshiba General Hospital introduced a departmental RIS/PACS (Radiology Information System/Picture Archiving and Communication System) in the radiology department in May, 1993. It has been used routinely since that time. In order to provide efficient means for clinicians to find and read many images, the system has been expanded to the neurosurgery and urology clinics and wards since May, 1995, and five image referring workstations now provide digital images to clinicians. In this paper we discuss an algorithm for image migration, one of the key issues to accomplish the expansion to outpatient clinics successfully, and propose the WYWIWYG (what you want is what you get) image transfer logic. This is the logic used to transfer images that physicians require refer without increasing the traffic between the image server and referring workstations. We accomplish the WYWIWYG logic by prioritizing exams the physicians have not yet viewed and by finding historical exams according to the modality, anatomy, and marking. Clinicians gave us comments from their first use of the system and suggested that the PACS enables clinicians to review images more efficiently compared to a film-based system. Our experience suggests that it is a key to the effective application of PACS in outpatient clinics to incorporate consideration patterns of clinicians on the migration algorithm.

  3. A comparative cost analysis of picture archiving and communications systems (PACS versus conventional radiology in the private sector

    Directory of Open Access Journals (Sweden)

    Indres Moodley

    2015-03-01

    Aim: To undertake an incremental cost analysis of PACS compared with conventional radiology to determine productivity gains, if any, at two private hospitals in Durban. Method: An incremental cost analysis for chest radiographs, computed tomography and magnetic resonance imaging brain scans with and without contrast were performed. The overall incremental cost for PACS in comparison with a conventional radiology site was determined. The net present value was also determined to evaluate the capital budgeting requirements for both systems. Results: The incremental cost of both capital and the radiology information system for installing PACS shows an expected increase. The incremental PACS image cost shows a reduction. Conclusion: The study provides a benchmark for the cost incurred when implementing PACS. It also provides a decision framework for radiology departments that plan to introduce PACS and helps to determine the feasibility of its introduction.

  4. Measuring the Scatter of the Mass–Richness Relation in Galaxy Clusters in Photometric Imaging Surveys by Means of Their Correlation Function

    Energy Technology Data Exchange (ETDEWEB)

    Campa, Julia; Estrada, Juan; Flaugher, Brenna

    2017-02-03

    The knowledge of the scatter in the mass-observable relation is a key ingredient for a cosmological analysis based on galaxy clusters in a photometric survey. We demonstrate here how the linear bias measured in the correlation function for clusters can be used to determine the value of the scatter. The new method is tested in simulations of a 5.000 square degrees optical survey up to z~1, similar to the ongoing Dark Energy Survey. The results indicate that the scatter can be measured with a precision of 5% using this technique.

  5. The impact of a picture archiving and communication system (PACS) upon an intensive care unit

    International Nuclear Information System (INIS)

    Watkins, Jessamy; Weatherburn, Gwyn; Bryan, Stirling

    2000-01-01

    Objective: The aim of the study was to assess the effect of the introduction of PACS (Picture Archiving and Communication System) upon image availability in an Intensive Care Unit (ICU) and the consequent impact upon the behaviour of the ICU physicians, in terms of the initiation of image-based clinical actions. Design: A before and after study was used to compare the speed of image availability prior to, and following, the implementation of a hospital-wide PACS. Setting: The research was part of an economic evaluation of PACS at Hammersmith Hospital, West London. Patients and participants: All ICU patients who were X-rayed during two pre-PACS and one post-PACS data collection periods were included within the study. Measurements: The times of: the X-ray request; acquisition; availability on ICU; and of any image-based clinical action taken by the ICU physician were recorded by radiographers and ICU physicians. Results: PACS significantly reduced the time between request and image availability on ICU for routine X-rays but did not have any measurable impact upon the time clinical actions were initiated by ICU physicians. The data on non-routine images were statistically inconclusive. Conclusions: This study shows that PACS significantly improves the speed of delivery of routine images to the ICU, but it appears that the instigation of image-based clinical actions is determined by other organisational factors in ICU, such as ward rounds, rather than the availability of the image for viewing. Further work is required on non-routine X-rays to clarify the impact of PACS on physician behaviour in clinically urgent situations

  6. Integration of a clinical trial database with a PACS

    International Nuclear Information System (INIS)

    Van Herk, M

    2014-01-01

    Many clinical trials use Electronic Case Report Forms (ECRF), e.g., from OpenClinica. Trial data is augmented if DICOM scans, dose cubes, etc. from the Picture Archiving and Communication System (PACS) are included for data mining. Unfortunately, there is as yet no structured way to collect DICOM objects in trial databases. In this paper, we obtain a tight integration of ECRF and PACS using open source software. Methods: DICOM identifiers for selected images/series/studies are stored in associated ECRF events (e.g., baseline) as follows: 1) JavaScript added to OpenClinica communicates using HTML with a gateway server inside the hospitals firewall; 2) On this gateway, an open source DICOM server runs scripts to query and select the data, returning anonymized identifiers; 3) The scripts then collects, anonymizes, zips and transmits selected data to a central trial server; 4) Here data is stored in a DICOM archive which allows authorized ECRF users to view and download the anonymous images associated with each event. Results: All integration scripts are open source. The PACS administrator configures the anonymization script and decides to use the gateway in passive (receiving) mode or in an active mode going out to the PACS to gather data. Our ECRF centric approach supports automatic data mining by iterating over the cases in the ECRF database, providing the identifiers to load images and the clinical data to correlate with image analysis results. Conclusions: Using open source software and web technology, a tight integration has been achieved between PACS and ECRF.

  7. Workshop for Open Source Universal Picture Archiving and Communication Systems (PACS)

    National Research Council Canada - National Science Library

    Tohme, Walid G

    2006-01-01

    .... The "Open Source Universal PACS Archive" workshop focused on current challenges of and open source solutions to the management of images and other clinical information in multi-center settings...

  8. Cardiology-oriented PACS

    Science.gov (United States)

    Silva, Augusto F. d.; Costa, Carlos; Abrantes, Pedro; Gama, Vasco; Den Boer, Ad

    1998-07-01

    This paper describes an integrated system designed to provide efficient means for DICOM compliant cardiac imaging archival, transmission and visualization based on a communications backbone matching recent enabling telematic technologies like Asynchronous Transfer Mode (ATM) and switched Local Area Networks (LANs). Within a distributed client-server framework, the system was conceived on a modality based bottom-up approach, aiming ultrafast access to short term archives and seamless retrieval of cardiac video sequences throughout review stations located at the outpatient referral rooms, intensive and intermediate care units and operating theaters.

  9. Operator interface design considerations for a PACS information management system

    Science.gov (United States)

    Steinke, James E.; Nabijee, Kamal H.; Freeman, Rick H.; Prior, Fred W.

    1990-08-01

    As prototype PACS grow into fully digital departmental and hospital-wide systems, effective information storage and retrieval mechanisms become increasingly important. Thus far, designers of PACS workstations have concentrated on image communication and display functionality. The new challenge is to provide appropriate operator interface environments to facilitate information retrieval. The "Marburg Model" 1 provides a detailed analysis of the functions, control flows and data structures used in Radiology. It identifies a set of "actors" who perform information manipulation functions. Drawing on this model and its associated methodology it is possible to identify four modes of use of information systems in Radiology: Clinical Routine, Research, Consultation, and Administration. Each mode has its own specific access requirements and views of information. An operator interface strategy appropriate for each mode will be proposed. Clinical Routine mode is the principal concern of PACS primary diagnosis workstations. In a full PACS implementation, such workstations must provide a simple and consistent navigational aid for the on-line image database, a local work list of cases to be reviewed, and easy access to information from other hospital information systems. A hierarchical method of information access is preferred because it provides the ability to start at high-level entities and iteratively narrow the scope of information from which to select subsequent operations. An implementation using hierarchical, nested software windows which fulfills such requirements shall be examined.

  10. Photometric Characterization of the Dark Energy Camera

    Science.gov (United States)

    Bernstein, G. M.; Abbott, T. M. C.; Armstrong, R.; Burke, D. L.; Diehl, H. T.; Gruendl, R. A.; Johnson, M. D.; Li, T. S.; Rykoff, E. S.; Walker, A. R.; Wester, W.; Yanny, B.

    2018-05-01

    We characterize the variation in photometric response of the Dark Energy Camera (DECam) across its 520 Mpix science array during 4 years of operation. These variations are measured using high signal-to-noise aperture photometry of >107 stellar images in thousands of exposures of a few selected fields, with the telescope dithered to move the sources around the array. A calibration procedure based on these results brings the rms variation in aperture magnitudes of bright stars on cloudless nights down to 2–3 mmag, with color corrections; and the use of an aperture-correction proxy. The DECam response pattern across the 2° field drifts over months by up to ±9 mmag, in a nearly wavelength-independent low-order pattern. We find no fundamental barriers to pushing global photometric calibrations toward mmag accuracy.

  11. Incremental picture archiving and communication system (PACS) - an appraisal

    International Nuclear Information System (INIS)

    Nagle, K.

    2000-01-01

    Digital storage phosphor radiography is slowly being introduced in Australia with more sites making the conversion from film/screen to computed radiography or a fully integrated Picture Archiving and Communication System (PACS). St Vincent's Hospital, Melbourne (SVHM) introduced partial PACS for general radiography in June 1996. This involved networking two Fuji CR Image Plate Readers and an existing Kodak KESPR400 Reader with viewing stations strategically placed in Medical Imaging, Casualty and the Intensive and Coronary Care units. No long-term storage device or archive facility was purchased. This installation coincided with the relocation of the Medical Imaging Department (MID) to a fully equipped new site as well as the introduction of the Kestral Radiology Management System. The transition has involved significant changes to the department's design, workflow and the radiographers' work practices. Copyright (1999) Australian Institute of Radiography

  12. Picture archiving and communication systems (PACS) in clinical practice

    International Nuclear Information System (INIS)

    Carreno Pedemonte, J.C.; Piqueras Pardellans, J.; Lucaya Layret, J.

    1994-01-01

    Picture archiving and communication systems (PACS) were developed as a technological response to the complex management of the growing amount of information generated by the different diagnostic imaging methods. This article documents the process of the progressive implementation, starting in January 1991, of the first complete PACS installed in our country. The system installed in our center is composed of acquisition modules for all the imaging methods (computed radiography, ultrasound, computed tomography, digital fluoroscopy and magnetic resonance), a central processing unit, an automatic optical disk for storage and a network of image viewing and diagnostic stations. The preliminary results obtained with its implementation demonstrate that PACS provide a series of functional advantages, especially at the image storage and display levels. In spite of these conveniences, the present high costs of acquisition and maintenance, together with certain technical problems as a result of its complexity, will signify that its generalized application for all imaging methods will not become a reality at most centers in the near future

  13. PACS war room for global teleradiology

    Science.gov (United States)

    Chen, Doris T.; Ho, Bruce K. T.; Chao, Woodrew; Taira, Ricky K.; Kangarloo, Hooshang

    1995-05-01

    UCLA is beginning teleradiology projects in Latin America, Asian Pacific, and the U.S. The UCLA teleradiology system communicates with remote imaging centers through a T1 based WAN and satellite technology. A network management center, i.e., PACS war room, with graphical user interface allows the system manager to monitor and control different elements of the system through various levels of abstraction from one location. The network manager software can monitor the activities of both hardware and software devices in the remote imaging centers, LAN and WAN performance, telearchiving and teleaccess pattern. Telearchiving can be monitored by graphically indicating large image movements between jukeboxes and over LAN or WAN. Once the teleradiology system is configured, the image flow pattern in a teleradiology center is predictable. Manual intervention of these teleradiology system functions is easily done through menu control in the war room display. A centralized network management with the global view of a teleradiology system has been developed. It can give commands to the elements of the system to tune the system for efficient utilization of the system resources. These managerial functions scale with the teleradiology system which is expandable to include many more potential remote imaging centers.

  14. Altered Circadian Food Anticipatory Activity Rhythms in PACAP Receptor 1 (PAC1 Deficient Mice.

    Directory of Open Access Journals (Sweden)

    Jens Hannibal

    Full Text Available Light signals from intrinsically photosensitive retinal ganglion cells (ipRGCs entrain the circadian clock and regulate negative masking. Two neurotransmitters, glutamate and Pituitary Adenylate Cyclase Activating Polypeptide (PACAP, found in the ipRGCs transmit light signals to the brain via glutamate receptors and the specific PACAP type 1 (PAC1 receptor. Light entrainment occurs during the twilight zones and has little effect on clock phase during daytime. When nocturnal animals have access to food only for a few hours during the resting phase at daytime, they adapt behavior to the restricted feeding (RF paradigm and show food anticipatory activity (FAA. A recent study in mice and rats demonstrating that light regulates FAA prompted us to investigate the role of PACAP/PAC1 signaling in the light mediated regulation of FAA. PAC1 receptor knock out (PAC1-/- and wild type (PAC1+/+ mice placed in running wheels were examined in a full photoperiod (FPP of 12:12 h light/dark (LD and a skeleton photoperiod (SPP 1:11:1:11 h L:DD:L:DD at 300 and 10 lux light intensity. Both PAC1-/- mice and PAC1+/+ littermates entrained to FPP and SPP at both light intensities. However, when placed in RF with access to food for 4-5 h during the subjective day, a significant change in behavior was observed in PAC1-/- mice compared to PAC1+/+ mice. While PAC1-/- mice showed similar FAA as PAC1+/+ animals in FPP at 300 lux, PAC1-/- mice demonstrated an advanced onset of FAA with a nearly 3-fold increase in amplitude compared to PAC1+/+ mice when placed in SPP at 300 lux. The same pattern of FAA was observed at 10 lux during both FPP and SPP. The present study indicates a role of PACAP/PAC1 signaling during light regulated FAA. Most likely, PACAP found in ipRGCs mediating non-image forming light information to the brain is involved.

  15. Photometric Study of Uranian Satellites

    Science.gov (United States)

    Kesten, Philip R.

    1998-01-01

    The best summary of my work at NASA is expressed in the following abstract, submitted the Division for Planetary Science of the American Astronomical Society and to be presented at the annual meeting in Madison in October. We report photometric measurements of Uranian satellites Miranda, Ariel, Umbriel and Titania (10.4 Aug. 1995), and Neptune's satellite Triton (21.2 Sept. 1995) with the infrared camera (IRCAM) and standard J (1.13 - 1.42 microns), H (1.53 - 1.81 microns), and K (2.00 - 2.41 microns) filters at the 3.8-m UKIRT telescope on Mauna Kea. The individual images frames are 256 x 256 pixels with a platescale of .286 arcsec/pixel, resulting in a 1.22 arc min field of view. This summer brought the IR photometry measurements nearly to a close. As indicated by the abstract above, I will present this work at the annual DPS meeting in October. In anticipation of the opening of the new Carl Sagan Laboratory for Cosmochemisty, of which I will be a participating member, I also devoted a considerable fraction of the summer to learning the biochemistry which underlies the experiments to be conducted. To put the end of the summary close to the beginning, it was a most productive summer.

  16. Photometric properties of Triton hazes

    Science.gov (United States)

    Hillier, J.; Veverka, J.

    1994-01-01

    Voyager imaging observations of Triton have been used to investigate the characteristics of the atmospheric hazes on Triton at three wavelengths: violet (0.41 micrometers), blue (0.48 micrometers), and green (0.56 micrometers). The globally averaged optical depth is wavelength dependent, varying from 0.034 in green to 0.063 in violet. These photometric results are dominated by the properties of localized discrete clouds rather than by those of the thinner, more widespread haze known to occur on Triton. The cloud particles are bright, with single-scattering albedos near unity at all three wavelengths, suggestive of a transparent icy condensate. The asymmetry parameter (+0.6) and the wavelength dependence of the optical depth both indicate cloud particles 0.2-0.4 micrometers in radius. The clouds are concentrated at 50-60 deg S latitude, where opacities up to three times the global average are observed. This is the same latitude region where most of the evidence for current surface activity is found, suggesting that the clouds may be related to the plumes or at least to some process connected with the sublimation of the south polar cap. The effects of possible temporal variations in the haze opacity are examined. Increases in the haze opacity tend to redden Triton. However, the degree of reddening is not sufficient to explain the full range of observed changed in Triton over the past decade; variations in the surface properties appear to be necessary.

  17. Internationalization of healthcare applications: a generic approach for PACS workstations.

    Science.gov (United States)

    Hussein, R; Engelmann, U; Schroeter, A; Meinzer, H P

    2004-01-01

    Along with the revolution of information technology and the increasing use of computers world-wide, software providers recognize the emerging need for internationalized, or global, software applications. The importance of internationalization comes from its benefits such as addressing a broader audience, making the software applications more accessible, easier to use, more flexible to support and providing users with more consistent information. In addition, some governmental agencies, e.g., in Spain, accept only fully localized software. Although the healthcare communication standards, namely, Digital Imaging and Communication in Medicine (DICOM) and Health Level Seven (HL7) support wide areas of internationalization, most of the implementers are still protective about supporting the complex languages. This paper describes a generic internationalization approach for Picture Archiving and Communication System (PACS) workstations. The Unicode standard is used to internationalize the application user interface. An encoding converter was developed to encode and decode the data between the rendering module (in Unicode encoding) and the DICOM data (in ISO 8859 encoding). An integration gateway was required to integrate the internationalized PACS components with the different PACS installations. To introduce a pragmatic example, the described approach was applied to the CHILI PACS workstation. The approach has enabled the application to handle the different internationalization aspects transparently, such as supporting complex languages, switching between different languages at runtime, and supporting multilingual clinical reports. In the healthcare enterprises, internationalized applications play an essential role in supporting a seamless flow of information between the heterogeneous multivendor information systems.

  18. Design and optimizing factors of PACS network architecture

    International Nuclear Information System (INIS)

    Tao Yonghao; Miao Jingtao

    2001-01-01

    Objective: Exploring the design and optimizing factors of picture archiving and communication system (PACS) network architecture. Methods: Based on the PACS of shanghai first hospital to performed the measurements and tests on the requirements of network bandwidth and transmitting rate for different PACS functions and procedures respectively in static and dynamic network traffic situation, utilizing the network monitoring tools which built-in workstations and provided by Windows NT. Results: No obvious difference between switch equipment and HUB when measurements and tests implemented in static situation except route which slow down the rate markedly. In dynamic environment Switch is able to provide higher bandwidth utilizing than HUB and local system scope communication achieved faster transmitting rate than global system. Conclusion: The primary optimizing factors of PACS network architecture design include concise network topology and disassemble tremendous global traffic to multiple distributed local scope network communication to reduce the traffic of network backbone. The most important issue is guarantee essential bandwidth for diagnosis procedure of medical imaging

  19. Astronomical Research Institute Photometric Results

    Science.gov (United States)

    Linder, Tyler R.; Sampson, Ryan; Holmes, Robert

    2013-01-01

    The Astronomical Research Institute (ARI) conducts astrometric and photometric studies of asteroids with a concentration on near-Earth objects (NEOs). A 0.76-m autoscope was used for photometric studies of seven asteroids of which two were main-belt targets and five were NEOs, including one potentially hazardous asteroid (PHA). These objects are: 3122 Florence, 3960 Chaliubieju, 5143 Heracles, (6455) 1992 HE, (36284) 2000 DM8, (62128) 2000 SO1, and 2010 LF86.

  20. Tracking PACS usage with open source tools.

    Science.gov (United States)

    French, Todd L; Langer, Steve G

    2011-08-01

    A typical choice faced by Picture Archiving and Communication System (PACS) administrators is deciding how many PACS workstations are needed and where they should be sited. Oftentimes, the social consequences of having too few are severe enough to encourage oversupply and underutilization. This is costly, at best in terms of hardware and electricity, and at worst (depending on the PACS licensing and support model) in capital costs and maintenance fees. The PACS administrator needs tools to asses accurately the use to which her fleet is being subjected, and thus make informed choices before buying more workstations. Lacking a vended solution for this challenge, we developed our own.

  1. Completion and Testing of PACS SWIR Channel

    Data.gov (United States)

    National Aeronautics and Space Administration — PACS SWIR has important technological innovations that will be necessary to meet the mission requirements for wide FOV, hyperangle capability, high polarimetric...

  2. PDA-phone-based instant transmission of radiological images over a CDMA network by combining the PACS screen with a Bluetooth-interfaced local wireless link.

    Science.gov (United States)

    Kim, Dong Keun; Yoo, Sun K; Park, Jeong Jin; Kim, Sun Ho

    2007-06-01

    Remote teleconsultation by specialists is important for timely, correct, and specialized emergency surgical and medical decision making. In this paper, we designed a new personal digital assistant (PDA)-phone-based emergency teleradiology system by combining cellular communication with Bluetooth-interfaced local wireless links. The mobility and portability resulting from the use of PDAs and wireless communication can provide a more effective means of emergency teleconsultation without requiring the user to be limited to a fixed location. Moreover, it enables synchronized radiological image sharing between the attending physician in the emergency room and the remote specialist on picture archiving and communication system terminals without distorted image acquisition. To enable rapid and fine-quality radiological image transmission over a cellular network in a secure manner, progressive compression and security mechanisms have been incorporated. The proposed system is tested over a code division Multiple Access 1x-Evolution Data-Only network to evaluate the performance and to demonstrate the feasibility of this system in a real-world setting.

  3. Integration of implant planning workflows into the PACS infrastructure

    Science.gov (United States)

    Gessat, Michael; Strauß, Gero; Burgert, Oliver

    2008-03-01

    The integration of imaging devices, diagnostic workstations, and image servers into Picture Archiving and Communication Systems (PACS) has had an enormous effect on the efficiency of radiology workflows. The standardization of the information exchange between the devices with the DICOM standard has been an essential precondition for that development. For surgical procedures, no such infrastructure exists. With the increasingly important role computerized planning and assistance systems play in the surgical domain, an infrastructure that unifies the communication between devices becomes necessary. In recent publications, the need for a modularized system design has been established. A reference architecture for a Therapy Imaging and Model Management System (TIMMS) has been proposed. It was accepted by the DICOM Working Group 6 as the reference architecture for DICOM developments for surgery. In this paper we propose the inclusion of implant planning systems into the PACS infrastructure. We propose a generic information model for the patient specific selection and positioning of implants from a repository according to patient image data. The information models are based on clinical workflows from ENT, cardiac, and orthopedic surgery as well as technical requirements derived from different use cases and systems. We show an exemplary implementation of the model for application in ENT surgery: the selection and positioning of an ossicular implant in the middle ear. An implant repository is stored in the PACS. It makes use of an experimental implementation of the Surface Mesh Module that is currently being developed as extension to the DICOM standard.

  4. Probabilistic Photometric Redshifts in the Era of Petascale Astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco Kind, Matias [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2014-01-01

    With the growth of large photometric surveys, accurately estimating photometric redshifts, preferably as a probability density function (PDF), and fully understanding the implicit systematic uncertainties in this process has become increasingly important. These surveys are expected to obtain images of billions of distinct galaxies. As a result, storing and analyzing all of these photometric redshift PDFs will be non-trivial, and this challenge becomes even more severe if a survey plans to compute and store multiple different PDFs. In this thesis, we have developed an end-to-end framework that will compute accurate and robust photometric redshift PDFs for massive data sets by using two new, state-of-the-art machine learning techniques that are based on a random forest and a random atlas, respectively. By using data from several photometric surveys, we demonstrate the applicability of these new techniques, and we demonstrate that our new approach is among the best techniques currently available. We also show how different techniques can be combined by using novel Bayesian techniques to improve the photometric redshift precision to unprecedented levels while also presenting new approaches to better identify outliers. In addition, our framework provides supplementary information regarding the data being analyzed, including unbiased estimates of the accuracy of the technique without resorting to a validation data set, identification of poor photometric redshift areas within the parameter space occupied by the spectroscopic training data, and a quantification of the relative importance of the variables used during the estimation process. Furthermore, we present a new approach to represent and store photometric redshift PDFs by using a sparse representation with outstanding compression and reconstruction capabilities. We also demonstrate how this framework can also be directly incorporated into cosmological analyses. The new techniques presented in this thesis are crucial

  5. Towards a theory of PACS deployment: an integrative PACS maturity framework.

    NARCIS (Netherlands)

    Wetering, R. van de; Batenburg, R.

    2014-01-01

    Owing to large financial investments that go along with the picture archiving and communication system (PACS) deployments and inconsistent PACS performance evaluations, there is a pressing need for a better understanding of the implications of PACS deployment in hospitals. We claim that there is a

  6. PACS: Do clinical users benefit from it as a training adjunct?

    Directory of Open Access Journals (Sweden)

    J van Heerden

    2011-05-01

    Full Text Available Background. Over the past four years, Steve Biko Academic Hospital has been in the process of implementing and refining the use of a picture archiving and communications system (PACS. As part of a post-implementation refining process, it is necessary to evaluate user-perceptions in order to improve on good system qualities and correct flaws. Aim. The aim of this study was to assess whether medical clinicians perceived PACS as a positive adjunct to training and teaching opportunities – specifically those opportunities related to radiological image viewing and interpretation as part of patient case discussions. Method. Standardised questionnaires with ‘free text’ and ‘option selection’ questions were distributed to clinicians who, as part of their training, rotated at Steve Biko Academic Hospital (where a PACS is in place as well as other teaching hospitals without a PACS. Between February 2009 and May 2009, approximately 400 questionnaires were distributed. As a result of constant academic rotations, leave schedules of medical staff and posts vacated, questionnaires could not be distributed to the entire target population that was estimated to be in the region of 550 medical clinicians (comprising senior medical students, interns, medical officers, registrars and consultants. Of the 400 questionnaires distributed, 189 completed questionnaires were returned. Completion of the questionnaires was voluntary and anonymous. Results and conclusion. Although a PACS relates specifically to the archiving and retrieval of radiological images and reports, it became clear from the feedback received from medical clinicians (who are ward-based, theatre-based or clinic-based users of a digital system that many other factors, such as lack of adequate hardware and sub-optimal personal IT proficiency, contributed to some of the negative PACS-related perceptions and ‘lost teaching opportunities’ reported. Negative comments specifically related to PACS

  7. Introduction to PAC/PAD

    International Nuclear Information System (INIS)

    Mahnke, H.E.

    1988-01-01

    Both methods, Perturbed Angular Correlation (PAC) utilizing radioactive probes and Perturbed Angular Distribution (PAD) following nuclear reactions measure hyperfine interaction parameters and allow to study magnetism on a rather local scale. While both techniques are based on the same theory the underlying concepts are quite different. Examples on local moments, influence of the nearest-neighbor to the magnetic field in ferromagnets, knight shift in nonmagnetic materials, and magnetism in high-temperature superconductors and related oxides illustrate the recent developments within the methods and the improvements in their sensitivity and resolution. (orig.)

  8. What Is A Picture Archiving And Communication System (PACS)?

    Science.gov (United States)

    Marceau, Carla

    1982-01-01

    A PACS is a digital system for acquiring, storing, moving and displaying picture or image information. It is an alternative to film jackets that has been made possible by recent breakthroughs in computer technology: telecommunications, local area nets and optical disks. The fundamental concept of the digital representation of image information is introduced. It is shown that freeing images from a material representation on film or paper leads to a dramatic increase in flexibility in our use of the images. The ultimate goal of a medical PACS system is a radiology department without film jackets. The inherent nature of digital images and the power of the computer allow instant free "copies" of images to be made and thrown away. These copies can be transmitted to distant sites in seconds, without the "original" ever leaving the archives of the radiology department. The result is a radiology department with much freer access to patient images and greater protection against lost or misplaced image information. Finally, images in digital form can be treated as data for the computer in image processing, which includes enhancement, reconstruction and even computer-aided analysis.

  9. From shared data to sharing workflow: Merging PACS and teleradiology

    International Nuclear Information System (INIS)

    Benjamin, Menashe; Aradi, Yinon; Shreiber, Reuven

    2010-01-01

    Due to a host of technological, interface, operational and workflow limitations, teleradiology and PACS/RIS were historically developed as separate systems serving different purposes. PACS/RIS handled local radiology storage and workflow management while teleradiology addressed remote access to images. Today advanced PACS/RIS support complete site radiology workflow for attending physicians, whether on-site or remote. In parallel, teleradiology has emerged into a service of providing remote, off-hours, coverage for emergency radiology and to a lesser extent subspecialty reading to subscribing sites and radiology groups. When attending radiologists use teleradiology for remote access to a site, they may share all relevant patient data and participate in the site's workflow like their on-site peers. The operation gets cumbersome and time consuming when these radiologists serve multi-sites, each requiring a different remote access, or when the sites do not employ the same PACS/RIS/Reporting Systems and do not share the same ownership. The least efficient operation is of teleradiology companies engaged in reading for multiple facilities. As these services typically employ non-local radiologists, they are allowed to share some of the available patient data necessary to provide an emergency report but, by enlarge, they do not share the workflow of the sites they serve. Radiology stakeholders usually prefer to have their own radiologists perform all radiology tasks including interpretation of off-hour examinations. It is possible with current technology to create a system that combines the benefits of local radiology services to multiple sites with the advantages offered by adding subspecialty and off-hours emergency services through teleradiology. Such a system increases efficiency for the radiology groups by enabling all users, regardless of location, to work 'local' and fully participate in the workflow of every site. We refer to such a system as SuperPACS.

  10. PACS and its hospital-wide implementation: A case study at the Madigan Army Medical Center

    International Nuclear Information System (INIS)

    Choi, Hyung Sik; Kim, Yong Min; Smith, Donald V.; Bender, Gregory N.

    1993-01-01

    PACS represents the future of radiology in modern hospitals. Workstations and databases can be developed to substantially increase clinician's productivity, improve diagnostic accuracy, and make a large amount of knowledge and patient information available on-line to the physician. Currently, there are several hospitals in the process of implementing a total PACS system. They include Madigan Army Medical Center (Tacoma, Washington), VA Hospital in Baltimore, and Hammersmith Hospital in London (1). In order to provide the radiologist, the clinicians, and other health personnel in Korea with the general concept of PACS and its up-to-date status report, we describe the MDIS system being implemented in MAMC (Madigan Army Medical Center) which is the first hospital-wide large-scale PACS in the world. The major PACS components in MAMC have been installed since March 1992 and the full system implementation will be completed by summer 1993. The goal of the MDIS system in MAMC is to increase to more than 90% filmless by the end of 1993. In this paper, we discuss the introduction and background of PACS and its potential benefits, the current status of PACS installation in MAMC and the future plan, and the flow of image data and text information in MAMC

  11. Automatically measuring brain ventricular volume within PACS using artificial intelligence.

    Science.gov (United States)

    Yepes-Calderon, Fernando; Nelson, Marvin D; McComb, J Gordon

    2018-01-01

    The picture archiving and communications system (PACS) is currently the standard platform to manage medical images but lacks analytical capabilities. Staying within PACS, the authors have developed an automatic method to retrieve the medical data and access it at a voxel level, decrypted and uncompressed that allows analytical capabilities while not perturbing the system's daily operation. Additionally, the strategy is secure and vendor independent. Cerebral ventricular volume is important for the diagnosis and treatment of many neurological disorders. A significant change in ventricular volume is readily recognized, but subtle changes, especially over longer periods of time, may be difficult to discern. Clinical imaging protocols and parameters are often varied making it difficult to use a general solution with standard segmentation techniques. Presented is a segmentation strategy based on an algorithm that uses four features extracted from the medical images to create a statistical estimator capable of determining ventricular volume. When compared with manual segmentations, the correlation was 94% and holds promise for even better accuracy by incorporating the unlimited data available. The volume of any segmentable structure can be accurately determined utilizing the machine learning strategy presented and runs fully automatically within the PACS.

  12. Interpretation of digital breast tomosynthesis: preliminary study on comparison with picture archiving and communication system (PACS) and dedicated workstation.

    Science.gov (United States)

    Kim, Young Seon; Chang, Jung Min; Yi, Ann; Shin, Sung Ui; Lee, Myung Eun; Kim, Won Hwa; Cho, Nariya; Moon, Woo Kyung

    2017-08-01

    To compare the diagnostic accuracy and efficiency in the interpretation of digital breast tomosynthesis (DBT) images using a picture archiving and communication system (PACS) and a dedicated workstation. 97 DBT images obtained for screening or diagnostic purposes were stored in both a workstation and a PACS and evaluated in combination with digital mammography by three independent radiologists retrospectively. Breast Imaging-Reporting and Data System final assessments and likelihood of malignancy (%) were assigned and the interpretation time when using the workstation and PACS was recorded. Receiver operating characteristic curve analysis, sensitivities and specificities were compared with histopathological examination and follow-up data as a reference standard. Area under the receiver operating characteristic curve values for cancer detection (0.839 vs 0.815, p = 0.6375) and sensitivity (81.8% vs 75.8%, p = 0.2188) showed no statistically significant differences between the workstation and PACS. However, specificity was significantly higher when analysing on the workstation than when using PACS (83.7% vs 76.9%, p = 0.009). When evaluating DBT images using PACS, only one case was deemed necessary to be reanalysed using the workstation. The mean time to interpret DBT images on PACS (1.68 min/case) was significantly longer than that to interpret on the workstation (1.35 min/case) (p < 0.0001). Interpretation of DBT images using PACS showed comparable diagnostic performance to a dedicated workstation, even though it required a longer reading time. Advances in knowledge: Interpretation of DBT images using PACS is an alternative to evaluate the images when a dedicated workstation is not available.

  13. Strengthening your ties to referring physicians through RIS/PACS integration.

    Science.gov (United States)

    Worthy, Susan; Rounds, Karla C; Soloway, Connie B

    2003-01-01

    Many imaging centers are turning to technology solutions to increase refering physician satisfaction, implementing such enhancements as automated report distribution, picture archiving and communications system (PACS), radiology information systems (RIS), and web-based results access. However, without seamless integration, these technology investments don't address the challenge at its core: convenient and reliable, two-way communication and interaction with referring physicians. In an integrated RIS/PACS solution, patient tracking in the RIS and PACS study status are logged and available to users. The time of the patient's registration at the imaging center, the exam start and completion time, the patient's departure time from the imaging center, and results status are all tracked and logged. An integrated RIS/PACS solution provides additional support to the radiologist, a critical factor that can improve the turnaround time of results to referring physicians. The RIS/PACS enhances the interpretation by providing the patient's history, which gives the radiologist additional insight and decreases the likelihood of missing a diagnostic element. In a tightly integrated RIS/PACS solution, results information is more complete. Physicians can view reports with associated images selected by the radiologist. They will also have full order information and complete imaging history including prior reports and images. Referring physicians can access and view images and exam notes at the same time that the radiologist is interpreting the exam. Without the benefit of an integrated RIS/PACS system, the referring physician would have to wait for the signed transcription to be released. In a seamlessly integrated solution, film-tracking modules within the RIS are fused with digital imaging workflow in the PACS. Users can see at a glance if a historical exam is available on film and benefit when a complete study history--both film-based and digital--is presented with the current

  14. Radiology department design to accommodate the future introduction of global PACS

    International Nuclear Information System (INIS)

    Naylor, A.F.

    1992-01-01

    In the light of the continuing development of pictorial archiving and communication systems (PACS) and image management and communications (MACS) systems it is appropriate to consider the provision that should be made in the design of a new or renovated department of radiology to accommodate these new technologies at either an earlier or later date. This paper considers 3 particular aspects of the influence of PACS on future department design: 1) the requirement for either more or less total department gross square feet, 2) the provision for the specific allocation of spaces at certain locations for PACS equipment and functions, and 3) the provision for dedicated pathways for fiber optic communications among the many locations in the department where PACS components would be located. (author). 1 fig

  15. Measuring the color and brightness of artificial sky glow from cities using an all-sky imaging system calibrated with astronomical methods in the Johnson-Cousins B and V photometric systems

    Science.gov (United States)

    Pipkin, Ashley; Duriscoe, Dan M.; Lughinbuhl, Christian

    2017-01-01

    Artificial light at night, when observed at some distance from a city, results in a dome of sky glow, brightest at the horizon. The spectral power distribution of electric light utilized will determine its color of the light dome and the amount of light will determine its brightness. Recent outdoor lighting technologies have included blue-rich light emitting diode (LED) sources that may increase the relative amount of blue to green light in sky glow compared to typical high pressure sodium (HPS) sources with warmer spectra. Measuring and monitoring this effect is important to the preservation of night sky visual quality as seen from undeveloped areas outside the city, such as parks or other protected areas, since the dark-adapted human eye is more sensitive to blue and green. We present a method using a wide field CCD camera which images the entire sky in both Johnson V and B photometric bands. Standard stars within the images are used for calibration. The resulting all-sky brightness maps, and a derived B-V color index map, provide a means to assess and track the impact of specific outdoor lighting practices. We also present example data from several cities, including Las Vegas, Nevada, Flagstaff, Arizona, and Cheyenne, Wyoming.

  16. Towards a theory of PACS deployment: an integrative PACS maturity framework.

    Science.gov (United States)

    van de Wetering, Rogier; Batenburg, Ronald

    2014-06-01

    Owing to large financial investments that go along with the picture archiving and communication system (PACS) deployments and inconsistent PACS performance evaluations, there is a pressing need for a better understanding of the implications of PACS deployment in hospitals. We claim that there is a gap in the research field, both theoretically and empirically, to explain the success of the PACS deployment and maturity in hospitals. Theoretical principles are relevant to the PACS performance; maturity and alignment are reviewed from a system and complexity perspective. A conceptual model to explain the PACS performance and a set of testable hypotheses are then developed. Then, structural equation modeling (SEM), i.e. causal modeling, is applied to validate the model and hypotheses based on a research sample of 64 hospitals that use PACS, i.e. 70 % of all hospitals in the Netherlands. Outcomes of the SEM analyses substantiate that the measurements of all constructs are reliable and valid. The PACS alignment-modeled as a higher-order construct of five complementary organizational dimensions and maturity levels-has a significant positive impact on the PACS performance. This result is robust and stable for various sub-samples and segments. This paper presents a conceptual model that explains how alignment in deploying PACS in hospitals is positively related to the perceived performance of PACS. The conceptual model is extended with tools as checklists to systematically identify the improvement areas for hospitals in the PACS domain. The holistic approach towards PACS alignment and maturity provides a framework for clinical practice.

  17. ESO & NOT photometric monitoring of the Cloverleaf quasar

    NARCIS (Netherlands)

    Ostensen, R; Remy, M; Lindblad, PO; Refsdal, S; Stabell, R; Surdej, J; Barthel, PD; Emanuelsen, PI; Festin, L; Gosset, E; Hainaut, O; Hakala, P; Hjelm, M; Hjorth, J; Hutsemekers, D; Jablonski, M; Kaas, AA; Kristen, H; Larsson, S; Magain, P; Pettersson, B; Pospieszalska-Surdej, A; Smette, A; Teuber, J; Thomsen, B; Van Drom, E

    1997-01-01

    The Cloverleaf quasar, H1413+117, has been photometrically monitored at ESO (La Silla, Chile) and with the NOT (La Palma, Spain) during the period 1987-1994. All good quality CCD frames have been successfully analysed using two independent methods (i.e. an automatic image decomposition technique and

  18. Galaxy Tagging: photometric redshift refinement and group richness enhancement

    Science.gov (United States)

    Kafle, P. R.; Robotham, A. S. G.; Driver, S. P.; Deeley, S.; Norberg, P.; Drinkwater, M. J.; Davies, L. J.

    2018-06-01

    We present a new scheme, galtag, for refining the photometric redshift measurements of faint galaxies by probabilistically tagging them to observed galaxy groups constructed from a brighter, magnitude-limited spectroscopy survey. First, this method is tested on the DESI light-cone data constructed on the GALFORM galaxy formation model to tests its validity. We then apply it to the photometric observations of galaxies in the Kilo-Degree Imaging Survey (KiDS) over a 1 deg2 region centred at 15h. This region contains Galaxy and Mass Assembly (GAMA) deep spectroscopic observations (i-bandhttps://github.com/pkaf/galtag.git.

  19. Photometric requirements for portable changeable message signs.

    Science.gov (United States)

    2001-09-01

    This project reviewed the performance of pchangeable message signs (PCMSs) and developed photometric standards to establish performance requirements. In addition, researchers developed photometric test methods and recommended them for use in evaluati...

  20. Actual concepts of digital PAC-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Roeder, J., E-mail: j.roeder@tu-bs.de; Herden, C., E-mail: cherden@viewplus.de [Braunschweig University of Technology, Institute of Physical and Theoretical Chemistry (Germany); Gardner, J. A., E-mail: john.gardner@viewplus.com [Oregon State University (United States); Becker, K. D., E-mail: k-d.becker@tu-bs.de [Braunschweig University of Technology, Institute of Physical and Theoretical Chemistry (Germany); Uhrmacher, M., E-mail: muhrmac@gwdg.de; Hofsaess, H., E-mail: hhofsae@uni-goettingen.de [University of Goettingen, II. Institute of Physics (Germany)

    2008-01-15

    In conventional perturbed angular correlation (PAC)-spectroscopy huge amounts of events are processed by fast electronics. Modern digital signal processing devices and the improvement in the computer technology in recent years allow today digital PAC-spectrometer setups capable to perform software-based data processing with all the benefits of storage, repeatable data analysis under different limits, and easy switching between different isotopes. In this paper we discuss experiences and concepts of a first realized digital PAC-spectrometer, which will be rebuild at ISOLDE/CERN/Geneva.

  1. Factors causing PAC cake fouling in PAC-MF (powdered activated carbon-microfiltration) water treatment systems.

    Science.gov (United States)

    Zhao, P; Takizawa, S; Katayama, H; Ohgaki, S

    2005-01-01

    Two pilot-scale powdered activated carbon-microfiltration (PAC-MF) reactors were operated using river water pretreated by a biofilter. A high permeate flux (4 m/d) was maintained in two reactors with different particle sizes of PAC. High concentration (20 g/L) in the PAC adsorption zone demonstrated 60-80% of organic removal rates. Analysis on the PAC cake fouling demonstrated that attached metal ions play more important role than organic matter attached on PAC to the increase of PAC cake resistance. Effects of factors which may cause PAC cake fouling in PAC-MF process were investigated and evaluated by batch experiments, further revealing that small particulates and metal ions in raw water impose prominent influence on the PAC cake layer formation. Fe (II) precipitates after being oxidized to Fe (III) during PAC adsorption and thus Fe(ll) colloids display more significant effect than other metal ions. At a high flux, PAC cake layer demonstrated a higher resistance with larger PAC due to association among colloids, metals and PAC particles, and easy migration of small particles in raw water into the void space in the PAC cake layer. Larger PAC possesses much more non-uniform particle size distribution and larger void space, making it easier for small colloids to migrate into the voids and for metal ions to associate with PAC particles by bridge effect, hence speeding up and intensifying the of PAC cake fouling on membrane surface.

  2. CHARACTERIZING AND PROPAGATING MODELING UNCERTAINTIES IN PHOTOMETRICALLY DERIVED REDSHIFT DISTRIBUTIONS

    International Nuclear Information System (INIS)

    Abrahamse, Augusta; Knox, Lloyd; Schmidt, Samuel; Thorman, Paul; Anthony Tyson, J.; Zhan Hu

    2011-01-01

    The uncertainty in the redshift distributions of galaxies has a significant potential impact on the cosmological parameter values inferred from multi-band imaging surveys. The accuracy of the photometric redshifts measured in these surveys depends not only on the quality of the flux data, but also on a number of modeling assumptions that enter into both the training set and spectral energy distribution (SED) fitting methods of photometric redshift estimation. In this work we focus on the latter, considering two types of modeling uncertainties: uncertainties in the SED template set and uncertainties in the magnitude and type priors used in a Bayesian photometric redshift estimation method. We find that SED template selection effects dominate over magnitude prior errors. We introduce a method for parameterizing the resulting ignorance of the redshift distributions, and for propagating these uncertainties to uncertainties in cosmological parameters.

  3. In vivo biological evaluation of 131I radiolabeled-paclitaxel glucuronide (131I-PAC-G)

    International Nuclear Information System (INIS)

    Aslan, O.; Biber Muftuler, F.Z.; Yurt Kilcar, A.; Ichedef, C.; Unak, P.

    2012-01-01

    Paclitaxel (PAC) is a natural occurring diterpene alkoloid originally isolated from the bark of Taxus Brevifolia. It is one of the most important antitumor agents for clinical treatment of ovarian, breast non-small cell lung and prostate cancers. It is known that these types of cancer cells have high β-glucuronidase enzyme which can catalyze the hydrolysis of glucuronides. This is why the synthesis compounds which undergo glucuronidation come into question in the imaging and therapy of these cancer cells. The aim of current study is conjugation of glucuronic acid (G) to the starting substance PAC, labeling with 131 I and to perform its in vivo biological evaluation. Glucuronic acid derived paclitaxel compound [paclitaxel-glucuronide (PAC-G)] was labeled with 131 I using iodogen method. According to thin layer radio chromatography (TLRC) method, the radiochemical yield of 131 I-PAC-G was 84.30 ± 7.40% (n=10). The biodistribution of 131 I-PAC-G in healthy female and male Wistar Albino rats has been investigated. Imaging studies on male Balb-C mice were performed by using the Kodak FX PRO in vivo Imaging System. The range of the breast/blood, breast/muscle; ovary/blood, ovary/muscle ratios is approximately between 1.29 and 11.34 in 240 min, and between 0.71 and 8.24 in 240 min for female rats. The prostate/blood and prostate/muscle ratio is between 1.94 and 6.95 in 30 min for male rats. All these experimental studies indicate that 131 I-PAC-G may potentially be used in breast, ovary and prostate tissues as an imaging agent. Also it is thought that 131 I-PAC-G bears a therapy potential because of the 131 I radionuclide and can be improved with further investigations. (orig.)

  4. Stereoscopic and photometric surface reconstruction in scanning electron microscopy

    International Nuclear Information System (INIS)

    Scherer, S.

    2000-01-01

    The scanning electron microscope (SEM) is one of the most important devices to examine microscopic structures as it offers images of a high contrast range with a large depth of focus. Nevertheless, three-dimensional measurements, as desired in fracture mechanics, have previously not been accomplished. This work presents a system for automatic, robust and dense surface reconstruction in scanning electron microscopy combining new approaches in shape from stereo and shape from photometric stereo. The basic theoretical assumption for a known adaptive window algorithm is shown not to hold in scanning electron microscopy. A constraint derived from this observation yields a new, simplified, hence faster calculation of the adaptive window. The correlation measure itself is obtained by a new ordinal measure coefficient. Shape from photometric stereo in the SEM is formulated by relating the image formation process with conventional photography. An iterative photometric ratio reconstruction is invented based on photometric ratios of backscatter electron images. The performance of the proposed system is evaluated using ground truth data obtained by three alternative shape recovery devices. Most experiments showed relative height accuracy within the tolerances of the alternative devices. (author)

  5. Status of the CP-PACS Project

    International Nuclear Information System (INIS)

    Ukawa, A.

    1995-01-01

    The CP-PACS Project, which started in April 1992, is a five-year plan to develop a massively parallel computer for carrying out research in computational physics with primary emphasis on lattice QCD. This article describes the architectural design of the CP-PACS computer, the entire computing system including the front end and mass storage, and results of benchmarks for the expected performance for lattice QCD applications. ((orig.))

  6. Combined PACS and intranet information system in a University Hospital

    International Nuclear Information System (INIS)

    Heiss, D.; Pfluger, T.; Pfeifer, K.J.; Hahn, K.; Koenig, A.; Endres, S.

    2000-01-01

    Purpose: The Department of Radiology at the University Hospital Innenstadt Munich provides all clinical departments of a large university hospital with several radiology units at different locations. During the last four years all units have been fully digitalized with a stepwise installation of a PACS. The PACS also processes images from the Nuclear Medicine Department. Methods: As image modalities, archive systems and review workstations, we use devices from multiple vendors, which are integrated into a consistent system using the DICOM standard. The hospital has developed its own RIS and an intranet information system, which provides access to all reports and images from radiology for all clinical departments inside the hospital. Additionally, other clinical information such as laboratory results or ECG examinations are available through the system. Results: After one year of operation, the system succeeded in the clinical routine work as the primary source for radiological reports and images as well as for laboratory values. Conclusion: The advantages of digitalization were, besides reduction of film cost, especially optimizations of work flow with access to digital images from every where at any time. (orig.) [de

  7. PAC spectroscopy of electronic ceramics

    International Nuclear Information System (INIS)

    Gardner, J.A.; Wang, R.; Schwenker, R.; Sommers, J.A.

    1991-01-01

    Dilute indium dopants in cerium oxides and YBa 2 Cu 3 O x have been studied by 111 In/Cd Perturbed Angular Correlation (PAC) spectroscopy. By controlling oxygen vacancy concentration in the cerium oxides through doping or high-temperature vacuum annealing, we have found that indium always forms a defect complex unless the sample is doped to reduce greatly the oxygen vacancy concentration. Three different vacancy-associated complexes are found with concentrations that depend on doping and oxygen stoichiometry. Another defect complex occurs in samples having negligible vacancy concentration. At low temperatures, evidence is found of interaction with an electronic hole trapped by 111 Cd after the radioactive decay of the 111 In parent. In YBa 2 Cu 3 O x the indium substitutes preferentially at the Y site but has measurable probability of substitution in at least one of the two copper sites. A symmetry change near 650 C is consistent with the well-documented orthorhombic/tetragonal transition for samples in air or oxygen. (author). 23 refs, 10 figs

  8. Making PACS the present, not the future.

    Science.gov (United States)

    Hunt, D

    1998-01-01

    Why haven't you moved forward with PACS? Have you just procrastinated or does your facility have legitimate reasons? Some say the technology is too confusing or too new, while others say the cost of PACS is too high. Many facilities say they haven't found a satisfactory way to deal with the conflicting opinions of their radiologists, IS department, administration, referring physicians and staff. Take time to compare the technology you do understand with something familiar such as your own PC or perhaps the current networks inside your facility. You'll soon begin to see that PACS is not a new technology, but rather a new methodology. To handle the perceived high cost of PACS, remember that every facility has different needs. Look at your work flow and then the many byproducts of PACS, such as marketing. If you are the first in your area to implement this new technology, you'll gain a marketing advantage in competing for referring physicians and managed care referral business. Follow the process you use to purchase other products, such as CT or MRI, as you investigate the vendors. Finally, make a plan! Determine departmental goals and gather information from vendors. Create a timeline, a financial plan and your marketing strategy. Together, these steps will help move PACS into the present for you.

  9. Implementation of MINI-PACS using the DICOM converter on the Web

    International Nuclear Information System (INIS)

    Ji, Youn Sang

    2000-01-01

    In recent years, medical procedures have become more complex, while financial pressures for shortened hospital stays and increased efficiency in patient care have increased. As a result, several shortcomings of present film-based systems for managing medical images have become apparent. Maintaining film space is labor intensive and consumes valuable space. Because only single copies of radiological examinations exist, they are prone to being lost or misplaced, thereby consuming additional valuable time and expense. In this paper, MINI-PACS for image archiving, transmission, and viewing offers a solution to these problems. Proposed MINI-PACS consists of mainly four parts such as Web Module, Client-Server Module, Internal Module, Acquisition Module. In addition, MINI-PACS system includes DICOM Converter that Non-DICOM file format converts standard file format. In Client-Server Module case, Proposed system is combined both SCU(Service Class User: Client) part and SCP(Service Class Provider: Server) part therefore this system provides the high resolution image processing techniques based on windows platform. Because general PACS system is too expensive for Medium and Small hospitals to install and operate the full-PACS. Also, we constructed Web Module for database connection through the WWW.=20

  10. Integration of PACS and HIS info the workflow of a nuclear medicine department. Experience in Regensburg

    International Nuclear Information System (INIS)

    Maenner, P.; Fuchs, E.; Marienhagen, J.; Schoenberger, J.; Eilles, C.; Tege, B.; Reicherzer, H.G.; Kurz, M.; Boerner, W.

    2006-01-01

    Aim: the development of new diagnostic techniques and the implementation of a modern quality control management system requires the continuous adaptation of existing data processing tools to the nuclear medicine diagnostic workflow. Furthermore, PACS connected to HIS facilitates and enhances the transfer of data and pictures, and satisfies the legal requirements for data retention as regulated by law. Therefore, the aim of this work is to present the architecture, structure and results of such a system newly installed in a department of nuclear medicine. Methods: initially, the nuclear medicine workflow was carefully analyzed and each step was correlated to the corresponding module. The standard SAP R/3 and IS-H / IS-H*med based software used for patient administration at the University of Regensburg Hospital was adapted to the needs of the Nuclear Medicine Department. The networking of the imaging systems was done by integration of a PACS. Finally, the PACS was connected to the HIS to allow the attachment of images to the medical report. Results, conclusion: by connecting the HIS to the nuclear medicine PACS, the workflow was significantly improved. The data management sequence starting at the reception desk, continuing through the nuclear medical examination, to the physician's final written and image report is clearly structured. Although high demands exist on technical support and administration the integration of PACS and HIS into the nuclear medicine workflow leads to enhanced efficiency and reduction in hospital costs. Patient and data management are considerably improved in this way. (orig.)

  11. Photometric variability in earthshine observations.

    Science.gov (United States)

    Langford, Sally V; Wyithe, J Stuart B; Turner, Edwin L

    2009-04-01

    The identification of an extrasolar planet as Earth-like will depend on the detection of atmospheric signatures or surface non-uniformities. In this paper we present spatially unresolved flux light curves of Earth for the purpose of studying a prototype extrasolar terrestrial planet. Our monitoring of the photometric variability of earthshine revealed changes of up to 23% per hour in the brightness of Earth's scattered light at around 600 nm, due to the removal of specular reflection from the view of the Moon. This variability is accompanied by reddening of the spectrum and results from a change in surface properties across the continental boundary between the Indian Ocean and Africa's east coast. Our results based on earthshine monitoring indicate that specular reflection should provide a useful tool in determining the presence of liquid water on extrasolar planets via photometric observations.

  12. Photometric Orbit of TX UMa

    Directory of Open Access Journals (Sweden)

    Kyu-Dong Oh

    1986-06-01

    Full Text Available Two-color photometric light curves (Oh and Chan 1984 of the eclipsing binary TX UMa have been analyzed by the method of differential corrections of the model of Wilson and Devinney(1971. The system found to be simi-detached with cooler and less massive component filling its Roche lobe. The absolute dimensions have been derived from the results of the photometric solutions with spectroscopic elements of Hiltner(1945. It is assumed that the B8V primary component is on the zero age main sequence stage of the core hydrogen burning and the secondary os at the core contraction stage after the shell hydrogen burning stage according to the Iben's (1967 evolutional tracks for 3.0m_solar and 1.0m_solar.

  13. Photometric device using optical fibers

    International Nuclear Information System (INIS)

    Boisde, Gilbert; Perez, J.-J.

    1981-02-01

    Remote measurements in radioactive environment are now possible with optical fibers. Measurement instruments developed by CEA are constitued of: - an optical probe (5 mm to 1 meter optical path length), - a photometric measurement device, - optical fiber links. 'TELEPHOT' is a photometric device for industrial installations. It is uses interferentiel filters for 2 to 5 simultaneous wave lengths. 'CRUDMETER' measures the muddiness of water. It can be equipped with a high sensitivity cell of 50 cm optical path length tested up to 250 bars. Coupling a double beam spectrophotometer to a remote optical probe, up to 1 meter optical path length, is carried out by means of an optical device using optical fibers links, eventually several hundred meter long. For these equipments special step index large core fibers, 1 to 1.5 mm in diameter, have been developed as well connectors. For industrial control and research these instruments offer new prospect thanks to optical fibers use [fr

  14. Combined PACS and intranet information system in a University Hospital; Kombiniertes PACS und Intranet-Informationssystem an einem Universitaetsklinikum

    Energy Technology Data Exchange (ETDEWEB)

    Heiss, D.; Pfluger, T.; Pfeifer, K.J.; Hahn, K. [Muenchen Univ. (Germany). Inst. fuer Radiologische Diagnostik; Koenig, A.; Endres, S. [Muenchen Univ. (Germany). Medizinische Klinik Innenstadt

    2000-06-01

    Purpose: The Department of Radiology at the University Hospital Innenstadt Munich provides all clinical departments of a large university hospital with several radiology units at different locations. During the last four years all units have been fully digitalized with a stepwise installation of a PACS. The PACS also processes images from the Nuclear Medicine Department. Methods: As image modalities, archive systems and review workstations, we use devices from multiple vendors, which are integrated into a consistent system using the DICOM standard. The hospital has developed its own RIS and an intranet information system, which provides access to all reports and images from radiology for all clinical departments inside the hospital. Additionally, other clinical information such as laboratory results or ECG examinations are available through the system. Results: After one year of operation, the system succeeded in the clinical routine work as the primary source for radiological reports and images as well as for laboratory values. Conclusion: The advantages of digitalization were, besides reduction of film cost, especially optimizations of work flow with access to digital images from every where at any time. (orig.) [German] Ziel: Das Institut fuer Radiologische Diagnostik am Universitaetsklinikum Muenchen - Innenstadt versorgt mit mehreren, dezentral gelegenen Roentgenbereichen alle klinischen Abteilungen eines grossen Universitaetsklinikums. In einem Projekt der vergangenen vier Jahre wurden alle Bereiche durch die schrittweise Installation eines PACS vollstaendig digitalisiert. Dabei wurden auch nuklearmedizinische Bilddaten aus der Klinik und Poliklinik fuer Nuklearmedizin im System verarbeitet. Methoden: Eingesetzt wurden als Bilderzeuger, Archivsystem und Befundungsstationen Geraete unterschiedlicher Hersteller, die dank des DICOM Standards in einem einheitlichen System integriert sind. Neben dem PACS wurde von Mitarbeitern der Klinik ein RIS und ein Intranet

  15. APPC - A new standardised coding system for trans-organisational PACS retrieval

    International Nuclear Information System (INIS)

    Fruehwald, F.; Lindner, A.; Mostbeck, G.; Hruby, W.; Fruehwald-Pallamar, J.

    2010-01-01

    As part of a general strategy to integrate the health care enterprise, Austria plans to connect the Picture Archiving and Communication Systems (PACS) of all radiological institutions into a nationwide network. To facilitate the search for relevant correlative imaging data in the PACS of different organisations, a coding system was compiled for all radiological procedures and necessary anatomical details. This code, called the Austrian PACS Procedure Code (APPC), was granted the status of a standard under HL7. Examples are provided of effective coding and filtering when searching for relevant imaging material using the APPC, as well as the planned process for future adjustments of the APPC. The implementation and how the APPC will fit into the future electronic environment, which will include an electronic health act for all citizens in Austria, are discussed. A comparison to other nationwide electronic health record projects and coding systems is given. Limitations and possible use in physical storage media are contemplated. (orig.)

  16. A demanding web-based PACS supported by web services technology

    Science.gov (United States)

    Costa, Carlos M. A.; Silva, Augusto; Oliveira, José L.; Ribeiro, Vasco G.; Ribeiro, José

    2006-03-01

    During the last years, the ubiquity of web interfaces have pushed practically all PACS suppliers to develop client applications in which clinical practitioners can receive and analyze medical images, using conventional personal computers and Web browsers. However, due to security and performance issues, the utilization of these software packages has been restricted to Intranets. Paradigmatically, one of the most important advantages of digital image systems is to simplify the widespread sharing and remote access of medical data between healthcare institutions. This paper analyses the traditional PACS drawbacks that contribute to their reduced usage in the Internet and describes a PACS based on Web Services technology that supports a customized DICOM encoding syntax and a specific compression scheme providing all historical patient data in a unique Web interface.

  17. Calibrating photometric redshifts of luminous red galaxies

    International Nuclear Information System (INIS)

    Padmanabhan, Nikhil; Budavari, Tamas; Schlegel, David J.; Bridges, Terry; Brinkmann, Jonathan

    2005-01-01

    We discuss the construction of a photometric redshift catalogue of luminous red galaxies (LRGs) from the Sloan Digital Sky Survey (SDSS), emphasizing the principal steps necessary for constructing such a catalogue: (i) photometrically selecting the sample, (ii) measuring photometric redshifts and their error distributions, and (iii) estimating the true redshift distribution. We compare two photometric redshift algorithms for these data and find that they give comparable results. Calibrating against the SDSS and SDSS–2dF (Two Degree Field) spectroscopic surveys, we find that the photometric redshift accuracy is σ~ 0.03 for redshifts less than 0.55 and worsens at higher redshift (~ 0.06 for z < 0.7). These errors are caused by photometric scatter, as well as systematic errors in the templates, filter curves and photometric zero-points. We also parametrize the photometric redshift error distribution with a sum of Gaussians and use this model to deconvolve the errors from the measured photometric redshift distribution to estimate the true redshift distribution. We pay special attention to the stability of this deconvolution, regularizing the method with a prior on the smoothness of the true redshift distribution. The methods that we develop are applicable to general photometric redshift surveys.

  18. Teleradiology and PACS - strategy of the Innsbruck University Hospital

    International Nuclear Information System (INIS)

    Vogl, R.

    2005-01-01

    Systems for management of digital imaging data are very important and widespread at the Innsbruck University Hospital and constitute a central component of the IT strategies followed by the hospital operating company TILAK (Tyrolean public hospitals). The particular goal is to integrate all imaging data into the electronic medical records and make these available online to each of the approx. 2500 clinic workstations and ensure electronic data exchange with other healthcare services. Teleradiology connections have been established at the University Clinic for Radiology since 1995; these have been continually expanded and linked to the central PACS. An eHealth web portal was recently established to facilitate transfer of images and findings from TILAK hospitals to other healthcare organizations. Registered users can be cleared for a limited time to access all radiological imaging data via this web portal. (orig.) [de

  19. SU-D-217BCD-01: Corrupted DICOM Image Recovering: A Clinical Experience.

    Science.gov (United States)

    Chen, L; Walz-Flannigan, A; Langer, S

    2012-06-01

    Colored DICOM secondary capture images generated from CT perfusion studies were corrupted if they were sent directly from a Siemens acquisition workstation to a GE viewing workstation. However, those images were properly displayed in the GE viewing workstation if they were transferred through a GE PACS first. The purpose of this work is to investigate the cause of image corruption and determine why passing through PACS corrected it. DICOM headers of corrupted and non-corrupted (sent through the PACS) images were compared with a free DICOM software tool (http://DVTK.org); the differences were highlighted. Certain header tags were found in non-corrupted images, but not in corrupted images. These tags were sequentially removed until the non- corrupted image became corrupted. Once a candidate tag was found, fresh corrupt images were modified by adding a 'repair' tag and tested. It was found that the absence of Planar Configuration (0028, 0006) is the cause of image corruption. This attribute is used in the DICOM color image to specify whether the color pixel data are sent color-by-plane or color-by- pixel and should be present if the Sample per Pixel (0028, 0002) tag has a value greater than 1. In our DICOM color images, the values of (0028, 0002) and Photometric Interpretation (0028, 0004) are 3 and RGB, respectively. Thus (0028, 0006) should equal 0 (color-by-pixel), which is used for uncompressed or lossless compressed transfer syntaxes. Adding this tag and setting the value to zero manually repaired corrupt images. Using open source DICOM tools and following the described process can be a valuable ally in the search for causes of image corruption. Comparing the headers and finding the handful of different tags rapidly led to an explanation that could be used by the vendor for a permanent fix. © 2012 American Association of Physicists in Medicine.

  20. New Variable Stars Discovered by Data Mining Images Taken during Recent Asteroid Photometric Observations. II. Results from July 2015 through December 2016

    Science.gov (United States)

    Papini, R.; Marchini, A.; Salvaggio, F.; Agnetti, D.; Bacci, P.; Banfi, M.; Bianciardi, G.; Collina, M.; Franco, L.; Galli, G.; Milani, M. G. A.; Lopresti, C.; Marino, G.; Rizzuti, L.; Ruocco, N.; Quadri, U.

    2017-12-01

    This paper follows the previous publication of new variables discovered at Astronomical Observatory, DSFTA, University of Siena, while observing asteroids in order to determine their rotational periods. Usually, this task requires time series images acquisition on a single field for as long as possible on a few nights not necessarily consecutive. Checking continually this "goldmine" allowed us to discover 57 variable stars not yet listed in catalogues or databases. While most of the new variables are eclipsing binaries, a few belong to the RR Lyrae or delta Scuti class. Since asteroid work is definitely a time-consuming activity, coordinated campaigns of follow-up with other observatories have been fundamental in order to determine the elements of the ephemeris and sometimes the right subclass of variability. Further observations of these new variables are therefore strongly encouraged in order to better characterize these stars, especially pulsating ones whose data combined with those taken during professional surveys seem to suggest the presence of light curve amplitude and period variations.

  1. THROES: a caTalogue of HeRschel Observations of Evolved Stars. I. PACS range spectroscopy

    Science.gov (United States)

    Ramos-Medina, J.; Sánchez Contreras, C.; García-Lario, P.; Rodrigo, C.; da Silva Santos, J.; Solano, E.

    2018-03-01

    This is the first of a series of papers presenting the THROES (A caTalogue of HeRschel Observations of Evolved Stars) project, intended to provide a comprehensive overview of the spectroscopic results obtained in the far-infrared (55-670 μm) with the Herschel space observatory on low-to-intermediate mass evolved stars in our Galaxy. Here we introduce the catalogue of interactively reprocessed Photoconductor Array Camera and Spectrometer (PACS) spectra covering the 55-200 μm range for 114 stars in this category for which PACS range spectroscopic data is available in the Herschel Science Archive (HSA). Our sample includes objects spanning a range of evolutionary stages, from the asymptotic giant branch to the planetary nebula phase, displaying a wide variety of chemical and physical properties. The THROES/PACS catalogue is accessible via a dedicated web-based interface and includes not only the science-ready Herschel spectroscopic data for each source, but also complementary photometric and spectroscopic data from other infrared observatories, namely IRAS, ISO, or AKARI, at overlapping wavelengths. Our goal is to create a legacy-value Herschel dataset that can be used by the scientific community in the future to deepen our knowledge and understanding of these latest stages of the evolution of low-to-intermediate mass stars. The THROES/PACS catalogue is accessible at http://https://throes.cab.inta-csic.es/

  2. Fusion breeder sphere - PAC blanket design

    International Nuclear Information System (INIS)

    Sullivan, J.D.; Palmer, B.J.F.

    1987-11-01

    There is a considerable world-wide effort directed toward the production of materials for fusion reactors. Many ceramic fabrication groups are working on making lithium ceramics in a variety of forms, to be incorporated into the tritium breeding blanket which will surround the fusion reactor. Current blanket designs include ceramic in either monolithic or packed sphere bed (sphere-pac) forms. The major thrust at AECL is the production of lithium aluminate spheres to be incorporated in a sphere-pac bed. Contemporary studies on breeder blanket design offer little insight into the requirements on the sizes of the spheres. This study examined the parameters which determine the properties of pressure drop and coolant requirements. It was determined that an optimised sphere-pac bed would be composed of two diameters of spheres: 75 weight % at 3 mm and 25 weight % at 0.3 mm

  3. Revised photometric elements of XZ And

    International Nuclear Information System (INIS)

    Giuricin, G.; Mardirossian, F.; Predolin, F.

    1980-01-01

    With the aid of Wood's (1972) computer program we have reanalyzed the photoelectric lightcurves of XZ And, made by Blitzstein (1954) and by Reinhardt (1967), from which appreciably different sets of photometric elements have previously been deduced. The photometric elements that we have derived separately from different lightcurves turned out to be in good agreement. Thus XZ And, whose seondary - somewhat larger than its hotter companion - appears to be roughly a G5-type star, has well-determined photometric elements. (author)

  4. Sloan Digital Sky Survey Photometric Calibration Revisited

    International Nuclear Information System (INIS)

    Marriner, John

    2012-01-01

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  5. Sloan Digital Sky Survey Photometric Calibration Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  6. A study on reduction effect of processing wastewater by introduction of PACS

    International Nuclear Information System (INIS)

    Ko, Shin Kwan; Yang, Han Jun; Han, Dong Kyoon; Kim, Wook Dong; Kang, Bung Sam

    2007-01-01

    There are some positive effects by the introduction of PACS (Picture Archiving Communication System). This study is to analyze the mutual relation between before and after of the introduction of PACS in terms of the environment effect. It is supposed to cause the reduction of developing and fixing wastewater according to the increase in the rate of a non-film. This study also show the amount of wastewater. Target places were the department of image medicine (diagnostic radiation) of the general hospitals in Seoul and Gyeonggido, which are equipped with full PACS. The authors examined questionnaires on the number of projection, the number of indirect projection, the amount of the film used, the number of radiation image CD loan, the amount of the developing and fixing solution used, the change of the amount of fixing wastewater. According to the analysis, we analyzed the change of the amount of developing and fixing solution per a film and the change of the amount of developing and fixing wastewater which is supposed to be reduced proportionally by the introduction of PACS. We got conclusion as below after analyzing 8 hospitals except the largest and the least amount of examination, film used, developing and fixing solution and the amount of developing and fixing wastewater in order to decrease the deviation from 10 general hospitals located in Seoul and Gyeonggido. We compared data one year before adopting PACS Versus 3 years after adopting PACS. The frequencies of examination increased to 7,357.7 cases per month but the amount of film used decreased to 90%, from 42,774.4 to 4,181.88 after adopting the PACS. 3 years after adopting PACS, monthly average amount of developing solution used decreased to 92% and the monthly average amount of fixing solution decreased to 86%. Monthly average amount of developing solution used per film increased to 1.49 times and fixing solution increased as much as three times. Monthly average wastewater for developing decreased to 88

  7. Benefits of cloud computing for PACS and archiving.

    Science.gov (United States)

    Koch, Patrick

    2012-01-01

    The goal of cloud-based services is to provide easy, scalable access to computing resources and IT services. The healthcare industry requires a private cloud that adheres to government mandates designed to ensure privacy and security of patient data while enabling access by authorized users. Cloud-based computing in the imaging market has evolved from a service that provided cost effective disaster recovery for archived data to fully featured PACS and vendor neutral archiving services that can address the needs of healthcare providers of all sizes. Healthcare providers worldwide are now using the cloud to distribute images to remote radiologists while supporting advanced reading tools, deliver radiology reports and imaging studies to referring physicians, and provide redundant data storage. Vendor managed cloud services eliminate large capital investments in equipment and maintenance, as well as staffing for the data center--creating a reduction in total cost of ownership for the healthcare provider.

  8. The Commercial Challenges Of Pacs

    Science.gov (United States)

    Vanden Brink, John A.

    1984-08-01

    The increasing use of digital imaging techniques create a need for improved methods of digital processing, communication and archiving. However, the commercial opportunity is dependent on the resolution of a number of issues. These issues include proof that digital processes are more cost effective than present techniques, implementation of information system support in the imaging activity, implementation of industry standards, conversion of analog images to digital formats, definition of clinical needs, the implications of the purchase decision and technology requirements. In spite of these obstacles, a market is emerging, served by new and existing companies, that may become a $500 million market (U.S.) by 1990 for equipment and supplies.

  9. PHOTOMETRIC SUPERNOVA CLASSIFICATION WITH MACHINE LEARNING

    International Nuclear Information System (INIS)

    Lochner, Michelle; Peiris, Hiranya V.; Lahav, Ofer; Winter, Max K.; McEwen, Jason D.

    2016-01-01

    Automated photometric supernova classification has become an active area of research in recent years in light of current and upcoming imaging surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope, given that spectroscopic confirmation of type for all supernovae discovered will be impossible. Here, we develop a multi-faceted classification pipeline, combining existing and new approaches. Our pipeline consists of two stages: extracting descriptive features from the light curves and classification using a machine learning algorithm. Our feature extraction methods vary from model-dependent techniques, namely SALT2 fits, to more independent techniques that fit parametric models to curves, to a completely model-independent wavelet approach. We cover a range of representative machine learning algorithms, including naive Bayes, k -nearest neighbors, support vector machines, artificial neural networks, and boosted decision trees (BDTs). We test the pipeline on simulated multi-band DES light curves from the Supernova Photometric Classification Challenge. Using the commonly used area under the curve (AUC) of the Receiver Operating Characteristic as a metric, we find that the SALT2 fits and the wavelet approach, with the BDTs algorithm, each achieve an AUC of 0.98, where 1 represents perfect classification. We find that a representative training set is essential for good classification, whatever the feature set or algorithm, with implications for spectroscopic follow-up. Importantly, we find that by using either the SALT2 or the wavelet feature sets with a BDT algorithm, accurate classification is possible purely from light curve data, without the need for any redshift information.

  10. PHOTOMETRIC SUPERNOVA CLASSIFICATION WITH MACHINE LEARNING

    Energy Technology Data Exchange (ETDEWEB)

    Lochner, Michelle; Peiris, Hiranya V.; Lahav, Ofer; Winter, Max K. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); McEwen, Jason D., E-mail: dr.michelle.lochner@gmail.com [Mullard Space Science Laboratory, University College London, Surrey RH5 6NT (United Kingdom)

    2016-08-01

    Automated photometric supernova classification has become an active area of research in recent years in light of current and upcoming imaging surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope, given that spectroscopic confirmation of type for all supernovae discovered will be impossible. Here, we develop a multi-faceted classification pipeline, combining existing and new approaches. Our pipeline consists of two stages: extracting descriptive features from the light curves and classification using a machine learning algorithm. Our feature extraction methods vary from model-dependent techniques, namely SALT2 fits, to more independent techniques that fit parametric models to curves, to a completely model-independent wavelet approach. We cover a range of representative machine learning algorithms, including naive Bayes, k -nearest neighbors, support vector machines, artificial neural networks, and boosted decision trees (BDTs). We test the pipeline on simulated multi-band DES light curves from the Supernova Photometric Classification Challenge. Using the commonly used area under the curve (AUC) of the Receiver Operating Characteristic as a metric, we find that the SALT2 fits and the wavelet approach, with the BDTs algorithm, each achieve an AUC of 0.98, where 1 represents perfect classification. We find that a representative training set is essential for good classification, whatever the feature set or algorithm, with implications for spectroscopic follow-up. Importantly, we find that by using either the SALT2 or the wavelet feature sets with a BDT algorithm, accurate classification is possible purely from light curve data, without the need for any redshift information.

  11. Cost-effective data storage/archival subsystem for functional PACS

    Science.gov (United States)

    Chen, Y. P.; Kim, Yongmin

    1993-09-01

    Not the least of the requirements of a workable PACS is the ability to store and archive vast amounts of information. A medium-size hospital will generate between 1 and 2 TBytes of data annually on a fully functional PACS. A high-speed image transmission network coupled with a comparably high-speed central data storage unit can make local memory and magnetic disks in the PACS workstations less critical and, in an extreme case, unnecessary. Under these circumstances, the capacity and performance of the central data storage subsystem and database is critical in determining the response time at the workstations, thus significantly affecting clinical acceptability. The central data storage subsystem not only needs to provide sufficient capacity to store about ten days worth of images (five days worth of new studies, and on the average, about one comparison study for each new study), but also supplies images to the requesting workstation in a timely fashion. The database must provide fast retrieval responses upon users' requests for images. This paper analyzes both advantages and disadvantages of multiple parallel transfer disks versus RAID disks for short-term central data storage subsystem, as well as optical disk jukebox versus digital recorder tape subsystem for long-term archive. Furthermore, an example high-performance cost-effective storage subsystem which integrates both the RAID disks and high-speed digital tape subsystem as a cost-effective PACS data storage/archival unit are presented.

  12. Communication of Unexpected and Significant Findings on Chest Radiographs With an Automated PACS Alert System.

    LENUS (Irish Health Repository)

    Hayes, Sara A

    2014-08-01

    An integral part of realizing the enormous potential of imaging in patient care is close communication between radiologists and referring physicians. One key element of this process is the communication of unexpected significant findings. The authors examined the performance of a PACS-based alert system in the appropriate communication of reports containing unexpected significant findings to referring physicians.

  13. A step towards PACS: The DS-1000 traumatology

    International Nuclear Information System (INIS)

    Schmidt, C.; Deininger, H.K.

    1989-01-01

    The development of new technologies is changing more and more the medical diagnostic. Analogous procedures are consistently making way for digital methods. 1980, the number of digital procedures amounted to 15%; 1990 according to general estimation, the number will already amount to 50%. It appears significant, within the framework of a new course, to promote the digitalisation not only in technical procedures but also in the organisation area. A central Picture Archiving and Communication System (PACS) is today considered an ideal solution, provided that the complete diagnostic imaging is carried out digitally. In the submitted is a report on a digital working unit for trauma patients. The initial results demonstrate that this concept is more than a promising attempt to replace conventional bone diagnostic in the future. The system presented is capable of demonstrations all clinically relevant changes of the traumatic skeleton, whereby the image quality corresponds approximately to a high-speed film-screen combination. Among the advantages, it should be emphasized in particular, the reduction in radiation, the rapid display of examination results and the integration in a Picture Archiving and Communication System (PACS) without any loos of information. (orig.) [de

  14. A neurosurgery/stereotactic radiotherapy dedicated PACS for conformal radiotherapy

    International Nuclear Information System (INIS)

    Lefkopoulos, D.; Bocquiault, P.; Levrier, M.; Merienne, L.; Schlienger, M.

    1995-01-01

    To realise conformal cerebral stereotactic irradiations we use a Neurosurgery/stereotactic dedicated PACS between two distant hospitals. It connects the stereotactic neurosurgery planification imaging system NEUROAXIS (Sopelem-Sofretec/Ste Anne Hospital) with the dosimetric TPS ARTEMIS-3D/Dosigray (Tenon Hospital). NEUROAXIS is a computer aided stereotactic biopsies and stereo-electroencephalographies, used by surgeons in operating room. The system determines the precise location data for Talairach radiological equipment (X ray source at 5 meters from film) and the geometry of scanner and MRI stereotactical referentials. It provides a full set of features for lesion localization, geometrical computations, surgical planifications, picture archiving, stereotactic angiography, CT and MRI image processing and networking. It sends images through the French public digital network ISDN (NUMERIS/France Telecom : 2x64 Kbits/s) from Ste Anne to Tenon Hospital. Stereotactic angiographic and CT images are reformatted into the DOSIGRAY image processing environment where 3-D dose distributions, displays and DVHs are computed to determine the optimal treatment. ARTEMIS-3D/Dosigray is a TPS for stereotactic radiotherapy devised by the Tenon Hospital for clinical methodology and 3D dose calculations, optimization software development and the Dosigray company for multimodality imaging, (2D(3D)) computer graphics for dose and anatomical representation and data networking. Communication within the radiation oncology department is provided by local area ETHERNET network, linking heterogeneous systems (Vaxstations-3200; Decstation (5000(240))) by means of different protocols. The works in progress are to send back via the same network the 3-D dose matrix to Neurosurgery department NEUROAXIS system. Our PACS is used since six months to treat patients. It has permitted to improve the treatment quality in comparison with our first version TPS ARTEMIS-3D

  15. A strongly quasiconvex PAC-Bayesian bound

    DEFF Research Database (Denmark)

    Thiemann, Niklas; Igel, Christian; Wintenberger, Olivier

    2017-01-01

    We propose a new PAC-Bayesian bound and a way of constructing a hypothesis space, so that the bound is convex in the posterior distribution and also convex in a trade-off parameter between empirical performance of the posterior distribution and its complexity. The complexity is measured by the Ku...

  16. PACS spectroscopy of OH/IR stars

    NARCIS (Netherlands)

    Lombaert, R.; de Vries, B.L.; Decin, L.; Blommaert, J.A.D.L.; Royer, Pierre; De Beck, E.; de Koter, A.; Waters, L.B.F.M.

    2011-01-01

    Observations of high-excitation molecular emission lines can greatly increase our understanding of AGB winds, as they trace the innermost regions of the circumstellar envelope. The PACS spectrometer on-board the Herschel Space Telescope1, provides for the first time the spectral resolution and

  17. Geometrical Acceptance Analysis for RPC PAC Trigger

    CERN Document Server

    Seo, Eunsung

    2010-01-01

    The CMS(Compact Muon Solenoid) is one of the four experiments that will analyze the collision results of the protons accelerated by the Large Hardron Collider(LHC) at CERN(Conseil Europen pour la Recherche Nuclaire). In case of the CMS experiment, the trigger system is divided into two stages : The Level-1 Trigger and High Level Trigger. The RPC(Resistive Plate Chamber) PAC(PAttern Comparator) Trigger system, which is a subject of this thesis, is a part of the Level-1 Muon Trigger System. Main task of the PAC Trigger is to identify muons, measures transverse momenta and select the best muon candidates for each proton bunch collision occurring every 25 ns. To calculate the value of PAC Trigger efficiency for triggerable muon, two terms of different efficiencies are needed ; acceptance efficiency and chamber efficiency. Main goal of the works described in this thesis is obtaining the acceptance efficiency of the PAC Trigger in each logical cone. Acceptance efficiency is a convolution of the chambers geometry an...

  18. Merits of usability testing for PACS selection

    NARCIS (Netherlands)

    Jorritsma, Wiard; Cnossen, Fokie; van Ooijen, Peter M. A.

    Objectives: To compare the usability of different Picture Archiving and Communication System (PACS) workstations, determine whether a usability test has added value with respect to the traditional way of comparing PACSs based on functional requirements, and to evaluate the appropriateness of a

  19. Fitting PAC spectra with a hybrid algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Alves, M. A., E-mail: mauro@sepn.org [Instituto de Aeronautica e Espaco (Brazil); Carbonari, A. W., E-mail: carbonar@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (Brazil)

    2008-01-15

    A hybrid algorithm (HA) that blends features of genetic algorithms (GA) and simulated annealing (SA) was implemented for simultaneous fits of perturbed angular correlation (PAC) spectra. The main characteristic of the HA is the incorporation of a selection criterion based on SA into the basic structure of GA. The results obtained with the HA compare favorably with fits performed with conventional methods.

  20. PACS: the second time around

    International Nuclear Information System (INIS)

    Foord, Keith

    1999-01-01

    Conquest Hospital was a Picture Archiving and Communication Systems development site, designed to inform the specification of low cost systems and to provide information on benefits and drawbacks. The American College of Radiologists/National Electrical Manufacturers Association 2.0 protocol was used for image management. The Regional Health Authority sponsored the system, initially installed in mid 1992. It used a high-speed dedicated optical fibre distributed data interface network and for teleradiology an Integrated Services Digital Network solution. Image and other data were captured and archived satisfactorily. Image reporting folders were manually constructed and sent to reporting viewstations. Radiologists were able to directly request 'ad hoc' images from archive. The reporting function of the associated but unlinked radiology information system was satisfactory. Identification was made of data transfer, ergonomic, single point of failure and many other issues. These informed re-specification and the commercial approach for a Digital Images Communication in Medicine/Hyper Text Mark-up Language Picture Archiving and Communication System, the first stages of which have been whole hospital re-networking, Intranet introduction, installation of new Computed Radiography/Fluorography and Computed Tomography/Magnetic Resonance Imaging segments and a new Radiology Information System. The Picture Archiving and Communication System is now seen as part of a full Electronic Patient Record system. Networking and provision of high quality Personal Computer hardware for data review are seen as a corporate responsibility and a hospital overhead, no longer borne by individual projects. Our present work is synergistic with the procurement of a new Clinical Information System and the further development of the hospital Intranet

  1. Photometric stability of the lunar surface

    Science.gov (United States)

    Kieffer, H.H.

    1997-01-01

    The rate at which cratering events currently occur on the Moon is considered in light of their influence on the use of the Moon as a radiometric standard. The radiometric effect of small impact events is determined empirically from the study of Clementine images. Events that would change the integral brightness of the moon by 1% are expected once per 1.4 Gyr. Events that cause a 1% shift in one pixel for low Earth-orbiting instruments with a 1-km nadir field of view are expected approximately once each 43 Myr. Events discernible at 1% radiometric resolution with a 5 arc-sec telescope resolution correspond to crater diameters of approximately 210 m and are expected once every 200 years. These rates are uncertain by a factor of two. For a fixed illumination and observation geometry, the Moon can be considered photometrically stable to 1 ?? 10-8per annum for irradiance, and 1 ?? 10-7per annum for radiance at a resolution common for spacecraft imaging instruments, exceeding reasonable instrument goals by six orders of magnitude. ?? 1997 Academic Press.

  2. Multicolor photometric study of M31 globular clusters

    International Nuclear Information System (INIS)

    Fan Zhou; Ma Jun; Zhou Xu

    2009-01-01

    We present the photometry of 30 globular clusters (GCs) and GC candidates in 15 intermediate-band filters covering the wavelength region from ∼3000 to ∼10000 A using the archival CCD images of M31 observed as part of the Beijing - Arizona - Taiwan - Connecticut (BATC) Multicolor Sky Survey. We transform these intermediate-band photometric data into the photometry in the standard U BV RI broad-bands. These M31 GC candidates are selected from the Revised Bologna Catalog (RBC V.3.5), and most of these candidates do not have any photometric data. Therefore, the presented photometric data are a supplement to the RBC V.3.5. We find that 4 out of 61 GCs and GC candidates in RBC V.3.5 do not show any signal on the BATC images at their locations. By applying a linear fit of the distribution in the color-magnitude diagram of blue GCs and GC candidates using data from the RBC V.3.5, in this study, we find the 'blue-tilt' of blue M31 GCs with a high confidence at 99.95% or 3.47σ for the confirmed GCs, and > 99.99% or 4.87σ for GCs and GC candidates. (research papers)

  3. Improving photometric redshift estimation using GPZ: size information, post processing, and improved photometry

    Science.gov (United States)

    Gomes, Zahra; Jarvis, Matt J.; Almosallam, Ibrahim A.; Roberts, Stephen J.

    2018-03-01

    The next generation of large-scale imaging surveys (such as those conducted with the Large Synoptic Survey Telescope and Euclid) will require accurate photometric redshifts in order to optimally extract cosmological information. Gaussian Process for photometric redshift estimation (GPZ) is a promising new method that has been proven to provide efficient, accurate photometric redshift estimations with reliable variance predictions. In this paper, we investigate a number of methods for improving the photometric redshift estimations obtained using GPZ (but which are also applicable to others). We use spectroscopy from the Galaxy and Mass Assembly Data Release 2 with a limiting magnitude of r Program Data Release 1 and find that it produces significant improvements in accuracy, similar to the effect of including additional features.

  4. In vivo biological evaluation of {sup 131}I radiolabeled-paclitaxel glucuronide ({sup 131}I-PAC-G)

    Energy Technology Data Exchange (ETDEWEB)

    Aslan, O.; Biber Muftuler, F.Z.; Yurt Kilcar, A.; Ichedef, C.; Unak, P. [Ege Univ., Izmir (Turkey). Dept. of Nuclear Applications

    2012-07-01

    Paclitaxel (PAC) is a natural occurring diterpene alkoloid originally isolated from the bark of Taxus Brevifolia. It is one of the most important antitumor agents for clinical treatment of ovarian, breast non-small cell lung and prostate cancers. It is known that these types of cancer cells have high {beta}-glucuronidase enzyme which can catalyze the hydrolysis of glucuronides. This is why the synthesis compounds which undergo glucuronidation come into question in the imaging and therapy of these cancer cells. The aim of current study is conjugation of glucuronic acid (G) to the starting substance PAC, labeling with {sup 131}I and to perform its in vivo biological evaluation. Glucuronic acid derived paclitaxel compound [paclitaxel-glucuronide (PAC-G)] was labeled with {sup 131}I using iodogen method. According to thin layer radio chromatography (TLRC) method, the radiochemical yield of {sup 131}I-PAC-G was 84.30 {+-} 7.40% (n=10). The biodistribution of {sup 131}I-PAC-G in healthy female and male Wistar Albino rats has been investigated. Imaging studies on male Balb-C mice were performed by using the Kodak FX PRO in vivo Imaging System. The range of the breast/blood, breast/muscle; ovary/blood, ovary/muscle ratios is approximately between 1.29 and 11.34 in 240 min, and between 0.71 and 8.24 in 240 min for female rats. The prostate/blood and prostate/muscle ratio is between 1.94 and 6.95 in 30 min for male rats. All these experimental studies indicate that {sup 131}I-PAC-G may potentially be used in breast, ovary and prostate tissues as an imaging agent. Also it is thought that {sup 131}I-PAC-G bears a therapy potential because of the {sup 131}I radionuclide and can be improved with further investigations. (orig.)

  5. North by Northwestern: initial experience with PACS at Northwestern Memorial Hospital

    Science.gov (United States)

    Channin, David S.; Hawkins, Rodney C.; Enzmann, Dieter R.

    2000-05-01

    This paper describes the initial phases and configuration of the Picture Archive and Communication System (PACS) deployed at Northwestern Memorial Hospital. The primary goals of the project were to improve service to patients, improve service to referring physicians, and improve the process of radiology. Secondary goals were to enhance the academic mission, and modernize institutional information systems. The system consists of a large number of heterogeneous imaging modalities sending imaging studies via DICOM to a GE medical Systems PathSpeed PACS. The radiology department workflow is briefly described. The system is currently storing approximately 140,000 studies and over 5 million images, growing by approximately 600 studies and 25,000 images per day. Data reflecting use of the short term and long term storage is provided.

  6. Java-based PACS and reporting system for nuclear medicine

    Science.gov (United States)

    Slomka, Piotr J.; Elliott, Edward; Driedger, Albert A.

    2000-05-01

    In medical imaging practice, images and reports often need be reviewed and edited from many locations. We have designed and implemented a Java-based Remote Viewing and Reporting System (JaRRViS) for a nuclear medicine department, which is deployed as a web service, at the fraction of the cost dedicated PACS systems. The system can be extended to other imaging modalities. JaRRViS interfaces to the clinical patient databases of imaging workstations. Specialized nuclear medicine applets support interactive displays of data such as 3-D gated SPECT with all the necessary options such as cine, filtering, dynamic lookup tables, and reorientation. The reporting module is implemented as a separate applet using Java Foundation Classes (JFC) Swing Editor Kit and allows composition of multimedia reports after selection and annotation of appropriate images. The reports are stored on the server in the HTML format. JaRRViS uses Java Servlets for the preparation and storage of final reports. The http links to the reports or to the patient's raw images with applets can be obtained from JaRRViS by any Hospital Information System (HIS) via standard queries. Such links can be sent via e-mail or included as text fields in any HIS database, providing direct access to the patient reports and images via standard web browsers.

  7. Teleradiology and PACS - strategy of the Innsbruck University Hospital; Teleradiologie und PACS - das Konzept des Universitaetsklinikums Innsbruck

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, R. [HITT - Health Information Technologies Tirol, Innsbruck (Austria)

    2005-08-01

    Systems for management of digital imaging data are very important and widespread at the Innsbruck University Hospital and constitute a central component of the IT strategies followed by the hospital operating company TILAK (Tyrolean public hospitals). The particular goal is to integrate all imaging data into the electronic medical records and make these available online to each of the approx. 2500 clinic workstations and ensure electronic data exchange with other healthcare services. Teleradiology connections have been established at the University Clinic for Radiology since 1995; these have been continually expanded and linked to the central PACS. An eHealth web portal was recently established to facilitate transfer of images and findings from TILAK hospitals to other healthcare organizations. Registered users can be cleared for a limited time to access all radiological imaging data via this web portal. (orig.) [German] Die Systeme zum digitalen Bilddatenmanagement haben grosse Bedeutung und weite Verbreitung an der Universitaetsklinik Innsbruck und sind zentraler Bestandteil der IT-Strategie der Krankenhausbetreibergesellschaft TILAK (Tiroler Landeskrankenanstalten). Ziel dabei ist es insbesondere, saemtliche Bilddaten in die elektronische Krankengeschichte zu integrieren und von jedem der ca. 2500 klinischen Arbeitsplaetze aus online zugreifbar zu machen sowie den elektronischen Datenaustausch mit anderen Gesundheitsdiensteanbietern zu gewaehrleisten. Seit 1995 bestehen Teleradiologieverbindungen der Universitaetsklinik fuer Radiologie; diese wurden laufend ausgebaut und die Einbindung in das zentrale PACS hergestellt. Zur Kommunikation von Bild- und Befunddaten aus den Krankenhaeusern der TILAK an andere Gesundheitseinrichtungen wurde kuerzlich ein eHealth WebPortal geschaffen, ueber das saemtliche radiologischen Bilddaten durch zeitbefristete Freigaben fuer registrierte Benutzer zugaenglich gemacht werden koennen. (orig.)

  8. Design and implementation of disaster recovery and business continuity solution for radiology PACS.

    Science.gov (United States)

    Mansoori, Bahar; Rosipko, Beverly; Erhard, Karen K; Sunshine, Jeffrey L

    2014-02-01

    In the digital era of radiology, picture archiving and communication system (PACS) has a pivotal role in retrieving and storing the images. Integration of PACS with all the health care information systems e.g., health information system, radiology information system, and electronic medical record has greatly improved access to patient data at anytime and anywhere throughout the entire enterprise. In such an integrated setting, seamless operation depends critically on maintaining data integrity and continuous access for all. Any failure in hardware or software could interrupt the workflow or data and consequently, would risk serious impact to patient care. Thus, any large-scale PACS now have an indispensable requirement to include deployment of a disaster recovery plan to ensure secure sources of data. This paper presents our experience with designing and implementing a disaster recovery and business continuity plan. The selected architecture with two servers in each site (local and disaster recovery (DR) site) provides four different scenarios to continue running and maintain end user service. The implemented DR at University Hospitals Health System now permits continuous access to the PACS application and its contained images for radiologists, other clinicians, and patients alike.

  9. Specification and evaluation of a regional PACS in the SaxTeleMed project

    Science.gov (United States)

    Lemke, Heinz U.; Niederlag, W.; Heuser, H.

    2002-05-01

    During the early development phase of PACS, its implementation was mainly a matter of the radiological department of a hospital. This is changing rapidly and PACS planning and realization is increasingly seen in the context of a hospital-wide approach. With a growth of networking amongst healthcare institutions and the growing relevance of teleradiological scenarios, new strategies must be followed which take not only local but also regional and global aspects of PACS into consideration. One such regional PACS project was initiated by the Ministry of Social Welfare of the Free State of Saxony in Germany. This 'reference model program for the digitization of imaging procedures and communication of images between hospitals in the free state of Saxony' (SaxTeleMed) covers seven regional projects distributed throughout Saxony. Each regional project is organized around so called lead hospitals, which network with other cooperating hospitals and medical practices. The regional reference projects are designed to be largely independent from one another. In some instances, however, a network connection between reference projects is also considered. Altogether, 39 hospitals and medical centers are involved in the model program. The aim of this program is to test the technical, organizational, legal and economic problems in the area of digitization and networking within the free State of Saxony. With the knowledge gained it is expected to improve future investment decisions in healthcare and above all to implement secure systems.

  10. THE FOURSTAR GALAXY EVOLUTION SURVEY (ZFOURGE): ULTRAVIOLET TO FAR-INFRARED CATALOGS, MEDIUM-BANDWIDTH PHOTOMETRIC REDSHIFTS WITH IMPROVED ACCURACY, STELLAR MASSES, AND CONFIRMATION OF QUIESCENT GALAXIES TO z ∼ 3.5

    International Nuclear Information System (INIS)

    Straatman, Caroline M. S.; Labbé, Ivo; Van Houdt, Josha; Spitler, Lee R.; Cowley, Michael; Quadri, Ryan F.; Papovich, Casey; Tran, Kim-Vy H.; Tomczak, Adam; Alcorn, Leo; Broussard, Adam; Forrest, Ben; Kawinwanichakij, Lalitwadee; Glazebrook, Karl; Nanayakkara, Themiya; Allen, Rebecca; Kacprzak, Glenn G.; Persson, S. Eric; Brammer, Gabriel B.; Van Dokkum, Pieter

    2016-01-01

    The FourStar galaxy evolution survey (ZFOURGE) is a 45 night legacy program with the FourStar near-infrared camera on Magellan and one of the most sensitive surveys to date. ZFOURGE covers a total of 400 arcmin 2 in cosmic fields CDFS, COSMOS and UDS, overlapping CANDELS. We present photometric catalogs comprising >70,000 galaxies, selected from ultradeep K s -band detection images (25.5–26.5 AB mag, 5 σ , total), and >80% complete to K s < 25.3–25.9 AB. We use 5 near-IR medium-bandwidth filters ( J 1 , J 2 , J 3 , H s , H l ) as well as broad-band K s at 1.05–2.16 μ m to 25–26 AB at a seeing of ∼0.″5. Each field has ancillary imaging in 26–40 filters at 0.3–8 μ m. We derive photometric redshifts and stellar population properties. Comparing with spectroscopic redshifts indicates a photometric redshift uncertainty σ z = 0.010, 0.009, and 0.011 in CDFS, COSMOS, and UDS. As spectroscopic samples are often biased toward bright and blue sources, we also inspect the photometric redshift differences between close pairs of galaxies, finding σ z ,pairs = 0.01–0.02 at 1 < z < 2.5. We quantify how σ z ,pairs depends on redshift, magnitude, spectral energy distribution type, and the inclusion of FourStar medium bands. σ z ,pairs is smallest for bright, blue star-forming samples, while red star-forming galaxies have the worst σ z ,pairs . Including FourStar medium bands reduces σ z ,pairs by 50% at 1.5 < z < 2.5. We calculate star formation rates (SFRs) based on ultraviolet and ultradeep far-IR Spitzer /MIPS and Herschel /PACS data. We derive rest-frame U − V and V − J colors, and illustrate how these correlate with specific SFR and dust emission to z = 3.5. We confirm the existence of quiescent galaxies at z ∼ 3, demonstrating their SFRs are suppressed by > ×15.

  11. THE FOURSTAR GALAXY EVOLUTION SURVEY (ZFOURGE): ULTRAVIOLET TO FAR-INFRARED CATALOGS, MEDIUM-BANDWIDTH PHOTOMETRIC REDSHIFTS WITH IMPROVED ACCURACY, STELLAR MASSES, AND CONFIRMATION OF QUIESCENT GALAXIES TO z ∼ 3.5

    Energy Technology Data Exchange (ETDEWEB)

    Straatman, Caroline M. S.; Labbé, Ivo; Van Houdt, Josha [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Spitler, Lee R.; Cowley, Michael [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Quadri, Ryan F.; Papovich, Casey; Tran, Kim-Vy H.; Tomczak, Adam; Alcorn, Leo; Broussard, Adam; Forrest, Ben; Kawinwanichakij, Lalitwadee [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Glazebrook, Karl; Nanayakkara, Themiya; Allen, Rebecca; Kacprzak, Glenn G. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Persson, S. Eric [Carnegie Observatories, Pasadena, CA 91101 (United States); Brammer, Gabriel B. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Van Dokkum, Pieter, E-mail: straatman@mpia.de [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); and others

    2016-10-10

    The FourStar galaxy evolution survey (ZFOURGE) is a 45 night legacy program with the FourStar near-infrared camera on Magellan and one of the most sensitive surveys to date. ZFOURGE covers a total of 400 arcmin{sup 2} in cosmic fields CDFS, COSMOS and UDS, overlapping CANDELS. We present photometric catalogs comprising >70,000 galaxies, selected from ultradeep K {sub s} -band detection images (25.5–26.5 AB mag, 5 σ , total), and >80% complete to K {sub s} < 25.3–25.9 AB. We use 5 near-IR medium-bandwidth filters ( J {sub 1}, J {sub 2}, J {sub 3}, H {sub s} , H {sub l} ) as well as broad-band K {sub s} at 1.05–2.16 μ m to 25–26 AB at a seeing of ∼0.″5. Each field has ancillary imaging in 26–40 filters at 0.3–8 μ m. We derive photometric redshifts and stellar population properties. Comparing with spectroscopic redshifts indicates a photometric redshift uncertainty σ {sub z} = 0.010, 0.009, and 0.011 in CDFS, COSMOS, and UDS. As spectroscopic samples are often biased toward bright and blue sources, we also inspect the photometric redshift differences between close pairs of galaxies, finding σ {sub z} {sub ,pairs} = 0.01–0.02 at 1 < z < 2.5. We quantify how σ {sub z} {sub ,pairs} depends on redshift, magnitude, spectral energy distribution type, and the inclusion of FourStar medium bands. σ {sub z} {sub ,pairs} is smallest for bright, blue star-forming samples, while red star-forming galaxies have the worst σ {sub z} {sub ,pairs}. Including FourStar medium bands reduces σ {sub z} {sub ,pairs} by 50% at 1.5 < z < 2.5. We calculate star formation rates (SFRs) based on ultraviolet and ultradeep far-IR Spitzer /MIPS and Herschel /PACS data. We derive rest-frame U − V and V − J colors, and illustrate how these correlate with specific SFR and dust emission to z = 3.5. We confirm the existence of quiescent galaxies at z ∼ 3, demonstrating their SFRs are suppressed by > ×15.

  12. THE PHOTOMETRIC CLASSIFICATION SERVER FOR Pan-STARRS1

    International Nuclear Information System (INIS)

    Saglia, R. P.; Bender, R.; Seitz, S.; Senger, R.; Snigula, J.; Phleps, S.; Wilman, D.; Tonry, J. L.; Burgett, W. S.; Chambers, K. C.; Heasley, J. N.; Kaiser, N.; Magnier, E. A.; Morgan, J. S.; Greisel, N.; Bailer-Jones, C. A. L.; Klement, R. J.; Rix, H.-W.; Smith, K.; Green, P. J.

    2012-01-01

    The Pan-STARRS1 survey is obtaining multi-epoch imaging in five bands (g P1 r P1 i P1 z P1 y P1 ) over the entire sky north of declination –30 deg. We describe here the implementation of the Photometric Classification Server (PCS) for Pan-STARRS1. PCS will allow the automatic classification of objects into star/galaxy/quasar classes based on colors and the measurement of photometric redshifts for extragalactic objects, and will constrain stellar parameters for stellar objects, working at the catalog level. We present tests of the system based on high signal-to-noise photometry derived from the Medium-Deep Fields of Pan-STARRS1, using available spectroscopic surveys as training and/or verification sets. We show that the Pan-STARRS1 photometry delivers classifications and photometric redshifts as good as the Sloan Digital Sky Survey (SDSS) photometry to the same magnitude limits. In particular, our preliminary results, based on this relatively limited data set down to the SDSS spectroscopic limits, and therefore potentially improvable, show that stars are correctly classified as such in 85% of cases, galaxies in 97%, and QSOs in 84%. False positives are less than 1% for galaxies, ≈19% for stars, and ≈28% for QSOs. Moreover, photometric redshifts for 1000 luminous red galaxies up to redshift 0.5 are determined to 2.4% precision (defined as 1.48 × Median|z phot – z spec |/(1 + z)) with just 0.4% catastrophic outliers and small (–0.5%) residual bias. For bluer galaxies up to the same redshift, the residual bias (on average –0.5%) trend, percentage of catastrophic failures (1.2%), and precision (4.2%) are higher, but still interestingly small for many science applications. Good photometric redshifts (to 5%) can be obtained for at most 60% of the QSOs of the sample. PCS will create a value-added catalog with classifications and photometric redshifts for eventually many millions of sources.

  13. LANSCE personnel access control system (PACS)

    International Nuclear Information System (INIS)

    Sturrock, J.C.; Gallegos, F.R.; Hall, M.J.

    1997-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. The Personnel Access Control System (PACS) is a component of the RSS that is designed to prevent personnel access to areas where prompt radiation is a hazard. PACS was designed to replace several older personnel safety systems (PSS) with a single modem unified design. Lessons learned from the operation over the last 20 years were incorporated into a redundant sensor, single-point failure safe, fault tolerant, and tamper-resistant system that prevents access to the beam areas by controlling the access keys and beam stoppers. PACS uses a layered philosophy to the physical and electronic design. The most critical assemblies are battery backed up, relay logic circuits; less critical devices use Programmable Logic Controllers (PLCs) for timing functions and communications. Outside reviewers have reviewed the operational safety of the design. The design philosophy, lessons learned, hardware design, software design, operation, and limitations of the device are described

  14. Photometric Studies of GEO Debris

    Science.gov (United States)

    Seitzer, Patrick; Cowardin, Heather M.; Barker, Edwin; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

    2009-01-01

    The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the SMARTS (Small and Medium Aperture Research Telescope System) 0.9-m at CTIO for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? In this paper we report on the photometric results. For a sample of 50 objects, more than 90 calibrated sequences of R-B-V-I-R magnitudes have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus

  15. Photometric Calibration of Consumer Video Cameras

    Science.gov (United States)

    Suggs, Robert; Swift, Wesley, Jr.

    2007-01-01

    Equipment and techniques have been developed to implement a method of photometric calibration of consumer video cameras for imaging of objects that are sufficiently narrow or sufficiently distant to be optically equivalent to point or line sources. Heretofore, it has been difficult to calibrate consumer video cameras, especially in cases of image saturation, because they exhibit nonlinear responses with dynamic ranges much smaller than those of scientific-grade video cameras. The present method not only takes this difficulty in stride but also makes it possible to extend effective dynamic ranges to several powers of ten beyond saturation levels. The method will likely be primarily useful in astronomical photometry. There are also potential commercial applications in medical and industrial imaging of point or line sources in the presence of saturation.This development was prompted by the need to measure brightnesses of debris in amateur video images of the breakup of the Space Shuttle Columbia. The purpose of these measurements is to use the brightness values to estimate relative masses of debris objects. In most of the images, the brightness of the main body of Columbia was found to exceed the dynamic ranges of the cameras. A similar problem arose a few years ago in the analysis of video images of Leonid meteors. The present method is a refined version of the calibration method developed to solve the Leonid calibration problem. In this method, one performs an endto- end calibration of the entire imaging system, including not only the imaging optics and imaging photodetector array but also analog tape recording and playback equipment (if used) and any frame grabber or other analog-to-digital converter (if used). To automatically incorporate the effects of nonlinearity and any other distortions into the calibration, the calibration images are processed in precisely the same manner as are the images of meteors, space-shuttle debris, or other objects that one seeks to

  16. RSO Characterization with Photometric Data Using Machine Learning

    Science.gov (United States)

    2015-10-18

    RSO Characterization with Photometric Data Using Machine Learning Michael Howard Charles River Analytics, Inc. Bernie Klem SASSO, Inc. Joe...and its behavior. This paper explores object characterization methods using photometric data. An important property of RSO photometric signatures is... photometric signature include geometry, orientation, material characteristics and stability. For this reason, it should be possible to recover these

  17. ArborZ: PHOTOMETRIC REDSHIFTS USING BOOSTED DECISION TREES

    International Nuclear Information System (INIS)

    Gerdes, David W.; Sypniewski, Adam J.; McKay, Timothy A.; Hao, Jiangang; Weis, Matthew R.; Wechsler, Risa H.; Busha, Michael T.

    2010-01-01

    Precision photometric redshifts will be essential for extracting cosmological parameters from the next generation of wide-area imaging surveys. In this paper, we introduce a photometric redshift algorithm, ArborZ, based on the machine-learning technique of boosted decision trees. We study the algorithm using galaxies from the Sloan Digital Sky Survey (SDSS) and from mock catalogs intended to simulate both the SDSS and the upcoming Dark Energy Survey. We show that it improves upon the performance of existing algorithms. Moreover, the method naturally leads to the reconstruction of a full probability density function (PDF) for the photometric redshift of each galaxy, not merely a single 'best estimate' and error, and also provides a photo-z quality figure of merit for each galaxy that can be used to reject outliers. We show that the stacked PDFs yield a more accurate reconstruction of the redshift distribution N(z). We discuss limitations of the current algorithm and ideas for future work.

  18. ASTEROID PHOTOMETRIC CATALOG V1.1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Asteroid Photometric Catalog (3rd update), Lagerkvist, et.al., 1993 [LAGERKVISTETAL1993], is a compilation of all asteroid lightcurve photometry published up to...

  19. Photometrical Observations "SBIRS GEO-2"

    Science.gov (United States)

    Sukhov, P. P.; Epishev, V. P.; Karpenko, G. F.; Sukhov, K. P.; Kudak, V. I.

    2015-08-01

    Photometrical observations GSS "SBIRS GEO 2" in B,V,R filters were carried near the equinoxes 2014-2015. Used velocity electrophotometer based on the FEU-79 in the pulse-counting mode. Received more than 25 light curves. From the known dimensions are defined; effective reflecting area - Sγλ, the spectral reflectance index - γλ, periods of light variation. Color-indices showed that in the reflected light flux from the GSS prevails "red" component. In the light curves are periodically dips and specular flash. This shows that GSS orbit is not in a static position specified triaxial orientation as in dynamic motion. Assumed following dynamics of the satellite "SBIRS GEO 2" in orbit. Helical scanning the Earth's surface visible infrared sensors satellite occurs with a period P1 = 15.66 sec. and swinging of the GSS about the direction of the motion vector of the satellite in an orbit with P2 = 62.64 sec., from the northern to the southern pole. Thus, during the period of swinging GSS going on 2 scan the visible part of the northern and southern hemispheres. In some dates observations dynamics work satellite in orbit changed.

  20. Measurement of the photometric characteristics of LEDs

    International Nuclear Information System (INIS)

    Nazarenko, L.A.; Zubkov, D.P.

    2015-01-01

    Proposed and implemented a method for measuring LEDs, which is based on self-calibration of the LED goniophotometer facility by using a trap-detector. Designed and manufactured automated goniophotometer, which provides a measurement of high power LEDs at a specified junction temperature. Designed and experimentally researched the photometer with a photometric sphere based diffuser, which meets all requirements of CIE for photometric measurements of LEDs

  1. PHOTOMETRY AND PHOTOMETRIC REDSHIFT CATALOGS FOR THE LOCKMAN HOLE DEEP FIELD

    International Nuclear Information System (INIS)

    Fotopoulou, S.; Salvato, M.; Hasinger, G.; Rovilos, E.; Brusa, M.; Lutz, D.; Burwitz, V.; Egami, E.; Henry, J. P.; Huang, J. H.; Rigopoulou, D.; Vaccari, M.

    2012-01-01

    We present broadband photometry and photometric redshifts for 187,611 sources located in ∼0.5 deg 2 in the Lockman Hole area. The catalog includes 388 X-ray-detected sources identified with the very deep XMM-Newton observations available for an area of 0.2 deg 2 . The source detection was performed on the R c -, z'-, and B-band images and the available photometry is spanning from the far-ultraviolet to the mid-infrared, reaching in the best-case scenario 21 bands. Astrometry corrections and photometric cross-calibrations over the entire data set allowed the computation of accurate photometric redshifts. Special treatment is undertaken for the X-ray sources, the majority of which are active galactic nuclei (AGNs). For normal galaxies, comparing the photometric redshifts to the 253 available spectroscopic redshifts, we achieve an accuracy of σ Δz/(1+z) = 0.036, with 12.6% outliers. For the X-ray-detected sources, compared to 115 spectroscopic redshifts, the accuracy is σ Δz/(1+z) = 0.069, with 18.3% outliers, where the outliers are defined as sources with |z phot – z spec | > 0.15 × (1 + z spec ). These results are a significant improvement over the previously available photometric redshifts for normal galaxies in the Lockman Hole, while it is the first time that photometric redshifts are computed and made public for AGNs for this field.

  2. CALIBRATION OF THE MEARTH PHOTOMETRIC SYSTEM: OPTICAL MAGNITUDES AND PHOTOMETRIC METALLICITY ESTIMATES FOR 1802 NEARBY M-DWARFS

    International Nuclear Information System (INIS)

    Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Newton, Elisabeth R.

    2016-01-01

    The MEarth Project is a photometric survey systematically searching the smallest stars near the Sun for transiting rocky planets. Since 2008, MEarth has taken approximately two million images of 1844 stars suspected to be mid-to-late M dwarfs. We have augmented this survey by taking nightly exposures of photometric standard stars and have utilized this data to photometrically calibrate the MEarth system, identify photometric nights, and obtain an optical magnitude with 1.5% precision for each M dwarf system. Each optical magnitude is an average over many years of data, and therefore should be largely immune to stellar variability and flaring. We combine this with trigonometric distance measurements, spectroscopic metallicity measurements, and 2MASS infrared magnitude measurements in order to derive a color–magnitude–metallicity relation across the mid-to-late M dwarf spectral sequence that can reproduce spectroscopic metallicity determinations to a precision of 0.1 dex. We release optical magnitudes and metallicity estimates for 1567 M dwarfs, many of which did not have an accurate determination of either prior to this work. For an additional 277 stars without a trigonometric parallax, we provide an estimate of the distance, assuming solar neighborhood metallicity. We find that the median metallicity for a volume-limited sample of stars within 20 pc of the Sun is [Fe/H] = −0.03 ± 0.008, and that 29/565 of these stars have a metallicity of [Fe/H] = −0.5 or lower, similar to the low-metallicity distribution of nearby G dwarfs. When combined with the results of ongoing and future planet surveys targeting these objects, the metallicity estimates presented here will be important for assessing the significance of any putative planet–metallicity correlation

  3. CALIBRATION OF THE MEARTH PHOTOMETRIC SYSTEM: OPTICAL MAGNITUDES AND PHOTOMETRIC METALLICITY ESTIMATES FOR 1802 NEARBY M-DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Newton, Elisabeth R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2016-02-20

    The MEarth Project is a photometric survey systematically searching the smallest stars near the Sun for transiting rocky planets. Since 2008, MEarth has taken approximately two million images of 1844 stars suspected to be mid-to-late M dwarfs. We have augmented this survey by taking nightly exposures of photometric standard stars and have utilized this data to photometrically calibrate the MEarth system, identify photometric nights, and obtain an optical magnitude with 1.5% precision for each M dwarf system. Each optical magnitude is an average over many years of data, and therefore should be largely immune to stellar variability and flaring. We combine this with trigonometric distance measurements, spectroscopic metallicity measurements, and 2MASS infrared magnitude measurements in order to derive a color–magnitude–metallicity relation across the mid-to-late M dwarf spectral sequence that can reproduce spectroscopic metallicity determinations to a precision of 0.1 dex. We release optical magnitudes and metallicity estimates for 1567 M dwarfs, many of which did not have an accurate determination of either prior to this work. For an additional 277 stars without a trigonometric parallax, we provide an estimate of the distance, assuming solar neighborhood metallicity. We find that the median metallicity for a volume-limited sample of stars within 20 pc of the Sun is [Fe/H] = −0.03 ± 0.008, and that 29/565 of these stars have a metallicity of [Fe/H] = −0.5 or lower, similar to the low-metallicity distribution of nearby G dwarfs. When combined with the results of ongoing and future planet surveys targeting these objects, the metallicity estimates presented here will be important for assessing the significance of any putative planet–metallicity correlation.

  4. Benchmark test of CP-PACS for lattice QCD

    International Nuclear Information System (INIS)

    Yoshie, Tomoteru

    1996-01-01

    The CP-PACS is a massively parallel computer dedicated for calculations in computational physics and will be in operation in the spring of 1996 at Center for Computational Physics, University of Tsukuba. In this paper, we describe the architecture of the CP-PACS and report the results of the estimate of the performance of the CP-PACS for typical lattice QCD calculations. (author)

  5. PHOTOMETRIC STEREO SHAPE-AND-ALBEDO-FROM-SHADING FOR PIXEL-LEVEL RESOLUTION LUNAR SURFACE RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    W. C. Liu

    2017-07-01

    Full Text Available Shape and Albedo from Shading (SAfS techniques recover pixel-wise surface details based on the relationship between terrain slopes, illumination and imaging geometry, and the energy response (i.e., image intensity captured by the sensing system. Multiple images with different illumination geometries (i.e., photometric stereo can provide better SAfS surface reconstruction due to the increase in observations. Photometric stereo SAfS is suitable for detailed surface reconstruction of the Moon and other extra-terrestrial bodies due to the availability of photometric stereo and the less complex surface reflecting properties (i.e., albedo of the target bodies as compared to the Earth. Considering only one photometric stereo pair (i.e., two images, pixel-variant albedo is still a major obstacle to satisfactory reconstruction and it needs to be regulated by the SAfS algorithm. The illumination directional difference between the two images also becomes an important factor affecting the reconstruction quality. This paper presents a photometric stereo SAfS algorithm for pixel-level resolution lunar surface reconstruction. The algorithm includes a hierarchical optimization architecture for handling pixel-variant albedo and improving performance. With the use of Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC photometric stereo images, the reconstructed topography (i.e., the DEM is compared with the DEM produced independently by photogrammetric methods. This paper also addresses the effect of illumination directional difference in between one photometric stereo pair on the reconstruction quality of the proposed algorithm by both mathematical and experimental analysis. In this case, LROC NAC images under multiple illumination directions are utilized by the proposed algorithm for experimental comparison. The mathematical derivation suggests an illumination azimuthal difference of 90 degrees between two images is recommended to achieve

  6. Traffic and trend analysis of local- and wide-area networks for a distributed PACS implementation

    Science.gov (United States)

    Gac, Robert J., Jr.; Harding, Douglas, Jr.; Weiser, John C.; Chacko, Anna K.; Radvany, Martin; Romlein, John R.

    2000-05-01

    Inductive Modeling Techniques (IMT) in a stand alone, distributed Picture Archiving and Communication System (PACS) or telemedicine environment can be utilized to monitor SNMP (Simple Network Management Protocol) enabled devices such as network switches, servers or workstations. A comprehensive approach using IMT is presented across the stages of the PACS lifecycle: Pre-PACS, Implementation, and Clinical Use. At each stage of the cycle, the results of IMT can be utilized to assist in assessing and forecasting future system loading. This loading represents a clinical trend analysis equating to the clinical workflow and delivery of services. Specific attention is directed to an understanding and thorough depiction of IMT methodology, focusing on the use of SNMP, the Management Information Base (MIB), and the data stream output that is mapped and placed in an object-oriented database and made available for web-based, real time, in-depth viewing and/or analysis. A thorough description of these outputs is presented, spotlighting potential report applications such as system failures; existing system, CPU, workstation, server and LAN/WAN link utilization; packet rates; application isolation; notification of system alarms; fault isolation; high/low bandwidth users; and data transfer rates. These types of data are increasingly required for programming LAN/WAN upgrades as digital imaging and PACS are implemented.

  7. Three-tiered integration of PACS and HIS toward next generation total hospital information system.

    Science.gov (United States)

    Kim, J H; Lee, D H; Choi, J W; Cho, H I; Kang, H S; Yeon, K M; Han, M C

    1998-01-01

    The Seoul National University Hospital (SNUH) started a project to innovate the hospital information facilities. This project includes installation of high speed hospital network, development of new HIS, OCS (order communication system), RIS and PACS. This project aims at the implementation of the first total hospital information system by seamlessly integrating these systems together. To achieve this goal, we took three-tiered systems integration approach: network level, database level, and workstation level integration. There are 3 loops of networks in SNUH: proprietary star network for host computer based HIS, Ethernet based hospital LAN for OCS and RIS, and ATM based network for PACS. They are linked together at the backbone level to allow high speed communication between these systems. We have developed special communication modules for each system that allow data interchange between different databases and computer platforms. We have also developed an integrated workstation in which both the OCS and PACS application programs run on a single computer in an integrated manner allowing the clinical users to access and display radiological images as well as textual clinical information within a single user environment. A study is in progress toward a total hospital information system in SNUH by seamlessly integrating the main hospital information resources such as HIS, OCS, and PACS. With the three-tiered systems integration approach, we could successfully integrate the systems from the network level to the user application level.

  8. The assessment of Picture Archiving and Communication System based on Canadian Infoway PACS Opinion Survey in Teaching Hospitals of Shiraz University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Fatemeh Bahador

    2017-10-01

    Full Text Available Introduction: Today the use of information technology in accordance with the rapid environmental changes and flexibility acquisition is necessary and unavoidable. Picture Archiving and Communication System (PACS is one of the medical information technology used in health facilities. PACS provides the images archive and transmission possibility electronically in different units of the teaching and treatment centers. This study aimed to assess the PACS system in teaching hospitals of Shiraz University of Medical Sciences based on a survey of Canadian Infoway. Method: This descriptive cross-sectional study was performed on 53 individuals selected through Two-Stage Stratified Random Sampling. The study population consisted of 156 PACS users in Shiraz University of Medical Sciences hospitals which were equipped with the PACS system in 2015. Data were collected by the valid and reliable customized questionnaire of Canadian Infoway. The reliability was measured by a pilot study on 25 PACS users; Cronbach’s Alpha was estimated 0.78. Data were analyzed using SPSS 18. Also, frequency, mean, standard deviation were used. Results: The results are presented in three sections: environment (Background Variables, benefits and challenges of PACS. As to the system availability, 20.8% of the users in the clinic, 75.5% in the diagnostic imaging department, only 3.8% in offices had access to the PACS. As to system accessibility, 49.1% of the users just had access to tests, 5.7% only to the reports, and 45.3% to both reports and tests. With respect to benefits of PACS, the mean was 4.16 (SD: 0.5 (five-point scale 1-5 estimated, and in challenges, the mean was 3.48(SD: 0.5 (five-point scale 1-5. Conclusion: The results showed that although PACS could eliminate many restrictions concerning the use of radiology images and films, there were challenges in this regard. Users are recommended to have access to PACS in all clinics, physicians’ offices, and diagnostic

  9. Process development and fabrication for sphere-pac fuel rods

    International Nuclear Information System (INIS)

    Welty, R.K.; Campbell, M.H.

    1981-06-01

    Uranium fuel rods containing sphere-pac fuel have been fabricated for in-reactor tests and demonstrations. A process for the development, qualification, and fabrication of acceptable sphere-pac fuel rods is described. Special equipment to control fuel contamination with moisture or air and the equipment layout needed for rod fabrication is described and tests for assuring the uniformity of the fuel column are discussed. Fuel retainers required for sphere-pac fuel column stability and instrumentation to measure fuel column smear density are described. Results of sphere-pac fuel rod fabrication campaigns are reviewed and recommended improvements for high throughput production are noted

  10. HFF-DeepSpace Photometric Catalogs of the 12 Hubble Frontier Fields, Clusters, and Parallels: Photometry, Photometric Redshifts, and Stellar Masses

    Science.gov (United States)

    Shipley, Heath V.; Lange-Vagle, Daniel; Marchesini, Danilo; Brammer, Gabriel B.; Ferrarese, Laura; Stefanon, Mauro; Kado-Fong, Erin; Whitaker, Katherine E.; Oesch, Pascal A.; Feinstein, Adina D.; Labbé, Ivo; Lundgren, Britt; Martis, Nicholas; Muzzin, Adam; Nedkova, Kalina; Skelton, Rosalind; van der Wel, Arjen

    2018-03-01

    We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have constructed homogeneous photometric catalogs for all six clusters and their parallels. To further expand these data catalogs, we have added ultra-deep K S -band imaging at 2.2 μm from the Very Large Telescope HAWK-I and Keck-I MOSFIRE instruments. We also add post-cryogenic Spitzer imaging at 3.6 and 4.5 μm with the Infrared Array Camera (IRAC), as well as archival IRAC 5.8 and 8.0 μm imaging when available. We introduce the public release of the multi-wavelength (0.2–8 μm) photometric catalogs, and we describe the unique steps applied for the construction of these catalogs. Particular emphasis is given to the source detection band, the contamination of light from the bright cluster galaxies (bCGs), and intra-cluster light (ICL). In addition to the photometric catalogs, we provide catalogs of photometric redshifts and stellar population properties. Furthermore, this includes all the images used in the construction of the catalogs, including the combined models of bCGs and ICL, the residual images, segmentation maps, and more. These catalogs are a robust data set of the Hubble Frontier Fields and will be an important aid in designing future surveys, as well as planning follow-up programs with current and future observatories to answer key questions remaining about first light, reionization, the assembly of galaxies, and many more topics, most notably by identifying high-redshift sources to target.

  11. The PAC-men revival : increasing need of PAC qualified colleagues

    NARCIS (Netherlands)

    Morren, J.; van der Heijden, S.

    2012-01-01

    More and more Protection, Automation, and Control (PAC) equipment is installed in the electricity (distribution) grid. For many employees of the network operators, the introduction of this equipment requires a change of mind, as this so-called secondary equipment is fundamentally different from the

  12. EVOLUTION OF GALAXY LUMINOSITY FUNCTION USING PHOTOMETRIC REDSHIFTS

    International Nuclear Information System (INIS)

    Ramos, B. H. F.; Pellegrini, P. S.; Da Costa, L. N.; Maia, M. A. G.; Ogando, R. L. C.; De Simoni, F.; Benoist, C.; Makler, M.; Mesquita, A. A.

    2011-01-01

    We examine the impact of using photometric redshifts for studying the evolution of both the global galaxy luminosity function (LF) and that for different galaxy types. To this end, we compare the LFs obtained using photometric redshifts from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) D1 field with those from the spectroscopic survey VIMOS VLT Deep Survey (VVDS) comprising ∼4800 galaxies. We find that for z ≤ 2.0, in the interval of magnitudes considered by this survey, the LFs obtained using photometric and spectroscopic redshifts show a remarkable agreement. This good agreement led us to use all four Deep fields of the CFHTLS comprising ∼386,000 galaxies to compute the LF of the combined fields and directly estimate the error in the parameters based on the field-to-field variation. We find that the characteristic absolute magnitude M* of Schechter fits fades by ∼0.7 mag from z ∼ 1.8 to z ∼ 0.3, while the characteristic density φ* increases by a factor of ∼4 in the same redshift interval. We use the galaxy classification provided by the template fitting program used to compute photometric redshifts and split the sample into galaxy types. We find that these Schechter parameters evolve differently for each galaxy type, an indication that their evolution is a combination of several effects: galaxy merging, star formation quenching, and mass assembly. All these results are compatible with those obtained by different spectroscopic surveys such as VVDS, DEEP2, and zCosmos, which reinforces the fact that photometric redshifts can be used to study galaxy evolution, at least for the redshift bins adopted so far. This is of great interest since future very large imaging surveys containing hundreds of millions of galaxies will allow us to obtain important precise measurements to constrain the evolution of the LF and to explore the dependence of this evolution on morphology and/or color helping constrain the mechanisms of galaxy evolution.

  13. Context indexing of digital cardiac ultrasound records in PACS

    Science.gov (United States)

    Lobodzinski, S. Suave; Meszaros, Georg N.

    1998-07-01

    Recent wide adoption of the DICOM 3.0 standard by ultrasound equipment vendors created a need for practical clinical implementations of cardiac imaging study visualization, management and archiving, DICOM 3.0 defines only a logical and physical format for exchanging image data (still images, video, patient and study demographics). All DICOM compliant imaging studies must presently be archived on a 650 Mb recordable compact disk. This is a severe limitation for ultrasound applications where studies of 3 to 10 minutes long are a common practice. In addition, DICOM digital echocardiography objects require physiological signal indexing, content segmentation and characterization. Since DICOM 3.0 is an interchange standard only, it does not define how to database composite video objects. The goal of this research was therefore to address the issues of efficient storage, retrieval and management of DICOM compliant cardiac video studies in a distributed PACS environment. Our Web based implementation has the advantage of accommodating both DICOM defined entity-relation modules (equipment data, patient data, video format, etc.) in standard relational database tables and digital indexed video with its attributes in an object relational database. Object relational data model facilitates content indexing of full motion cardiac imaging studies through bi-directional hyperlink generation that tie searchable video attributes and related objects to individual video frames in the temporal domain. Benefits realized from use of bi-directionally hyperlinked data models in an object relational database include: (1) real time video indexing during image acquisition, (2) random access and frame accurate instant playback of previously recorded full motion imaging data, and (3) time savings from faster and more accurate access to data through multiple navigation mechanisms such as multidimensional queries on an index, queries on a hyperlink attribute, free search and browsing.

  14. Radiological reporting system developed with FileMakerPro. Cooperation with HIS, RIS, and PACS

    International Nuclear Information System (INIS)

    Kawakami, Satoshi

    2004-01-01

    This article briefly describes our original radiological reporting system. This system was developed with the widely used database software FileMakerPro (ver 5.5). The reporting system can obtain information about patients and examinations from a radiology information system (RIS) by the Open DataBase Connectivity (ODBC) technique. By clicking the button on the reporting system, the corresponding Digital Imaging and Communications in Medicine (DICOM) images can be displayed on a picture archiving and communication system (PACS) workstation monitor. Reference images in JPEG format can be easily moved from PACS to the reporting system. Reports produced by the reporting system are distributed to the hospital information system (HIS) in Portable Document Format (PDF), through another web server. By utilizing the capacity of FileMakerPro, the human-machine interface of the system has been able to be improved easily. In addition, cooperation with HIS, RIS, and PACS could be constructed. Therefore, this original system would contribute to increasing the efficiency of radiological diagnosis. (author)

  15. A hospital-wide picture archiving and communication system (PACS): the views of users and providers of the radiology service at Hammersmith Hospital

    International Nuclear Information System (INIS)

    Watkins, Jessamy

    1999-01-01

    Objective: To obtain users' views of the new picture archiving and communication system (PACS) from clinical and radiological staff at Hammersmith Hospital, UK. Methods: Semi-structured interviews were used to ascertain the views of staff, following an interview schedule which covered aspects of: (1) their use of PACS, (2) facilities available, (3) the perceived quality of images, (4) reporting, (5) image availability, (6) image accessibility, (7) training, and (8) ease of use of PACS. Results: Interviews were carried out with 34 key users and providers of the radiological service at Hammersmith Hospital. Overall, staff were very satisfied with PACS particularly in terms of image availability. All staff said that they preferred PACS to the previous, conventional radiology service. Conclusions: The key implications of issues raised by staff were: the impact of 'down-time' and the importance of an efficient back-up system, the requirement for sufficient short-term storage to prevent images being off-line during clinical situations, the usefulness of the folder system for management of the images, the need to access images for teaching purposes, the advantage of having a default display protocol to facilitate radiological reporting, and the requirement for flexible, yet effective, training to ensure that the system is utilised to its full potential by users

  16. The Detector Physics and Applications Center—DePAC

    Science.gov (United States)

    Plothow-Besch, H.; Besch, H.-J.; Fiorini, C.; Grupen, C.; Hassard, J.; Longoni, A.; Walenta, A. H.

    2001-09-01

    A new project, the "Detector Physics and Applications Center (DePAC)", is presented. DePAC is a general detector and sensor database, which is not application specific, on the Internet. DePAC collects and explains the physics, the technology and the application of a wide range of radiation detectors. DePAC also collects and describes information about noise problems, front-end electronics, data transfer, processing and storage. DePAC provides short write-ups and source code of all sorts of detector related software depending on availability. DePAC collects useful constants and properties of materials in an exhaustive series of tables and graphs. DePAC also acts as a point of contact for researchers and industry in an interdisciplinary way, e.g. in biology, in medicine, in materials research and in high energy or nuclear physics. Last but not least, DePAC aims to develop also into a virtual lecturing school and serves as a tutorial for students and all interested scientists.

  17. The Detector Physics and Applications Center - DePAC

    International Nuclear Information System (INIS)

    Plothow-Besch, H.; Besch, H.-J.; Fiorini, C.; Grupen, C.; Hassard, J.; Longoni, A.; Walenta, A.H.

    2001-01-01

    A new project, the 'Detector Physics and Applications Center (DePAC)', is presented. DePAC is a general detector and sensor database, which is not application specific, on the Internet. DePAC collects and explains the physics, the technology and the application of a wide range of radiation detectors. DePAC also collects and describes information about noise problems, front-end electronics, data transfer, processing and storage. DePAC provides short write-ups and source code of all sorts of detector related software depending on availability. DePAC collects useful constants and properties of materials in an exhaustive series of tables and graphs. DePAC also acts as a point of contact for researchers and industry in an interdisciplinary way, e.g. in biology, in medicine, in materials research and in high energy or nuclear physics. Last but not least, DePAC aims to develop also into a virtual lecturing school and serves as a tutorial for students and all interested scientists

  18. The Detector Physics and Applications Center - DePAC

    CERN Document Server

    Plothow-Besch, H; Fiorini, C; Grupen, C; Hassard, J; Longoni, A; Walenta, Albert H

    2001-01-01

    A new project, the 'Detector Physics and Applications Center (DePAC)', is presented. DePAC is a general detector and sensor database, which is not application specific, on the Internet. DePAC collects and explains the physics, the technology and the application of a wide range of radiation detectors. DePAC also collects and describes information about noise problems, front-end electronics, data transfer, processing and storage. DePAC provides short write-ups and source code of all sorts of detector related software depending on availability. DePAC collects useful constants and properties of materials in an exhaustive series of tables and graphs. DePAC also acts as a point of contact for researchers and industry in an interdisciplinary way, e.g. in biology, in medicine, in materials research and in high energy or nuclear physics. Last but not least, DePAC aims to develop also into a virtual lecturing school and serves as a tutorial for students and all interested scientists.

  19. bond activation and catalysis by Ru -pac complexes

    Indian Academy of Sciences (India)

    and their reactivity towards oxidation of a few organic compounds. Keywords. Kinetics; catalysis; -O–O- bond activation; Ru-pac complex; oxidation. 1. Introduction. Ru-pac complexes exhibit catalytic properties,1 in homogeneous conditions in the presence of oxygen atom donors, that mimic the biological enzymatic oxi-.

  20. Defining photometric peculiar type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    González-Gaitán, S.; Pignata, G.; Förster, F.; Gutiérrez, C. P.; Bufano, F.; Galbany, L.; Hamuy, M.; De Jaeger, T. [Millennium Institute of Astrophysics, Casilla 36-D, Santiago (Chile); Hsiao, E. Y.; Phillips, M. M. [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Folatelli, G. [Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa 277-8583 (Kavli IPMU, WPI) (Japan); Anderson, J. P., E-mail: sgonzale@das.uchile.cl [European Southern Observatory, Alonso de Córdova 3107, Casilla 19, Santiago (Chile)

    2014-11-10

    We present a new photometric identification technique for SN 1991bg-like type Ia supernovae (SNe Ia), i.e., objects with light curve characteristics such as later primary maxima and the absence of a secondary peak in redder filters. This method is capable of selecting this sub-group from the normal type Ia population. Furthermore, we find that recently identified peculiar sub-types such as SNe Iax and super-Chandrasekhar SNe Ia have photometric characteristics similar to 91bg-like SNe Ia, namely, the absence of secondary maxima and shoulders at longer wavelengths, and can also be classified with our technique. The similarity of these different SN Ia sub-groups perhaps suggests common physical conditions. This typing methodology permits the photometric identification of peculiar SNe Ia in large upcoming wide-field surveys either to study them further or to obtain a pure sample of normal SNe Ia for cosmological studies.

  1. Can PACS make a radiology department more competitive?

    International Nuclear Information System (INIS)

    Strickland, Nicola H.

    1999-01-01

    One of the motives for putting in a picture archiving and communication system (PACS) is to improve efficiency and hence enhance the competitive strength of the radiology department. Many would argue that it is now negligent to consider installing an old fashioned conventional radiology department rather than a PACS. In considering the issue it is important to be clear about the nature of the competition facing radiologists. This varies depending on the country and upon whether the institution is public or private. PACS can potentially help to overcome this competition in two ways: by providing real-time radiology, and by enabling teleradiology. Success in these areas requires state-of-the-art implementations of PACS, particularly clinically relevant PACS software, and adequate staffing levels

  2. V 463 Cyg: revised photometric elements

    International Nuclear Information System (INIS)

    Giuricin, G.; Mardirossian, F.; Ferluga, S.

    1982-01-01

    Using Wood's (1972) model we have re-analyzed Vetesnik's (1968) two-colour photoelectric light curves of eclipsing binary V 463 Cyg. Our photometric solutions which confirm the presence of a large amount of third light do not greatly differ from previous results. The eclipsing pair appears to be composed of an A 0 primary attended by a somewhat smaller (around G 5) companion. In view of the large ratio of the radii this component cannot be in the main sequence. It seems to be more advanced in the evolution than the primary, like common secondaries of Algols, and it appears to fill its Roche lobe for our photometric mass ratio. (author)

  3. Changes of workflow in a radiolocigal department with RIS, PACS and flatpanel detectors implementation

    International Nuclear Information System (INIS)

    Imhof, H.; Dirisamer, A.; Fischer, H.; Grampp, S.; Heiner, L.; Kaderk, M.; Krestan, C.; Kainberger, F.

    2002-01-01

    Implementation of radiological information systems (RIS) and picture archiving and communicating systems (PACS) results in significant changes of workflow in a radiological department. Additional connection with flatpanel detectors leads to a shortening of the work process. RIS and PACS implementation alone reduces the complete workflow by 21-80%. With flatpanel technology the image production process is further shortened by 25-30%. The workflow-steps are changed from original 17-12 with the implementation of RIS and PACS and to 5 with the integrated use of flatpanels.This clearly recognizable advantages in the workflow need an according financial investment. Several studies could show that the capitalisationfactor calculated over eight years is positive, with a gain range between 5-25%. Whether the additional implementation of flatpanel detectors results also in a positive capitalisation over the years, cannot be estimated exactly, at the moment, because the experiences are too short. Particuarly critical are the interfaces, which needs a constant quality control. Our flatpanel detector-system is fixed, special images - as we have them in about 3-5% of all cases - need still conventional filmscreen or phosphorplate-systems. Full-spine and long-leg examinations cannot be performed with sufficient exactness. Without any questions implementation of integrated RIS, PACS and flatpanel detector-system needs excellent training of the employees, because of the changes in workflow etc. The main profits of such an integrated implementation are an increase in quality in image and report datas, easier handling - there are almost no more cassettes necessary - and excessive shortening of workflow. (orig.) [de

  4. Effect of PAC dosage in a pilot-scale PAC-MBR treating micro-polluted surface water.

    Science.gov (United States)

    Hu, Jingyi; Shang, Ran; Deng, Huiping; Heijman, Sebastiaan G J; Rietveld, Luuk C

    2014-02-01

    To address the water scarcity issue and advance the traditional drinking water treatment technique, a powdered activated carbon-amended membrane bioreactor (PAC-MBR) is proposed for micro-polluted surface water treatment. A pilot-scale study was carried out by initially dosing different amounts of PAC into the MBR. Comparative results showed that 2g/L performed the best among 0, 1, 2 and 3g/L PAC-MBR regarding organic matter and ammonia removal as well as membrane flux sustainability. 1g/L PAC-MBR exhibited a marginal improvement in pollutant removal compared to the non-PAC system. The accumulation of organic matter in the bulk mixture of 3g/L PAC-MBR led to poorer organic removal and severer membrane fouling. Molecular weight distribution of the bulk liquid in 2g/L PAC-MBR revealed the synergistic effects of PAC adsorption/biodegradation and membrane rejection on organic matter removal. Additionally, a lower amount of soluble extracellular polymer substances in the bulk can be secured in 21 days operation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Microgeometry capture and RGB albedo estimation by photometric stereo without demosaicing

    Science.gov (United States)

    Quéau, Yvain; Pizenberg, Mathieu; Durou, Jean-Denis; Cremers, Daniel

    2017-03-01

    We present a photometric stereo-based system for retrieving the RGB albedo and the fine-scale details of an opaque surface. In order to limit specularities, the system uses a controllable diffuse illumination, which is calibrated using a dedicated procedure. In addition, we rather handle RAW, non-demosaiced RGB images, which both avoids uncontrolled operations on the sensor data and simplifies the estimation of the albedo in each color channel and of the normals. We finally show on real-world examples the potential of photometric stereo for the 3D-reconstruction of very thin structures from a wide variety of surfaces.

  6. Workflow optimization beyond RIS and PACS

    International Nuclear Information System (INIS)

    Treitl, M.; Wirth, S.; Lucke, A.; Nissen-Meyer, S.; Trumm, C.; Rieger, J.; Pfeifer, K.-J.; Reiser, M.; Villain, S.

    2005-01-01

    Technological progress and the rising cost pressure on the healthcare system have led to a drastic change in the work environment of radiologists today. The pervasive demand for workflow optimization and increased efficiency of its activities raises the question of whether by employment of electronic systems, such as RIS and PACS, the potentials of digital technology are sufficiently used to fulfil this demand. This report describes the tasks and structures in radiology departments, which so far are only insufficiently supported by commercially available electronic systems but are nevertheless substantial. We developed and employed a web-based, integrated workplace system, which simplifies many daily tasks of departmental organization and administration apart from well-established tasks of documentation. Furthermore, we analyzed the effects exerted on departmental workflow by employment of this system for 3 years. (orig.) [de

  7. NICOLAU: compact unit for photometric characterization of automotive lighting from near-field measurements

    Science.gov (United States)

    Royo, Santiago; Arranz, Maria J.; Arasa, Josep; Cattoen, Michel; Bosch, Thierry

    2005-02-01

    The present works depicts a measurement technique intended to enhance the characterization procedures of the photometric emissions of automotive headlamps, with potential applications to any light source emission, either automotive or non-automotive. A CCD array with a precisely characterized optical system is used for sampling the luminance field of the headlamp just a few centimetres in front of it, by combining deflectometric techniques (yielding the direction of the light beams) and photometric techniques (yielding the energy travelling in each direction). The CCD array scans the measurement plane using a self-developed mechanical unit and electronics, and then image-processing techniques are used for obtaining the photometric behaviour of the headlamp in any given plane, in particular in the plane and positions required by current normative, but also on the road, on traffic signs, etc. An overview of the construction of the system, of the considered principle of measurement, and of the main calibrations performed on the unit is presented. First results concerning relative measurements are presented compared both to reference data from a photometric tunnel and from a plane placed 5m away from the source. Preliminary results for the absolute photometric calibration of the system are also presented for different illumination beams of different headlamps (driving and passing beam).

  8. Numbering of vertebrae on MRI using a PACS cross-referencing tool

    International Nuclear Information System (INIS)

    Paik, Nam Chull; Lim, Chun Soo; Jang, Ho Suk

    2012-01-01

    Background: For the detection and documentation of numeric variations on spine magnetic resonance imaging (MRI), different techniques have previously been introduced. However, these methods require additional special imaging algorithms, software, or devices. We intend to introduce a vertebral numbering method using the existing picture archiving and communication system (PACS) and MRI system. Purpose: To assess the accuracy of a method for numbering presacral vertebrae based on the cross-referencing of two sagittal MRI series. Material and Methods: This study was a retrospective review of 224 consecutive patients who underwent both lumbar MRI with cervicothoracic scan and whole spine radiographic examinations. A radiologist and a neurosurgeon independently counted the number of presacral vertebrae in a cranial-to-caudal approach with cross-referencing of cervicothoracic and lumbar MRI sagittal series on the PACS workstation. Radiographic numbering from the cervical through the thoracic to the lumbar vertebrae, as a reference standard, was completed independently by the two reviewers. An analysis of the inter-observer and intermodality agreements of radiography and MRI was done. Results: In all cases except one, concordant numbering existed between the two modalities of MRI cross-referencing and radiographs combination. Both observers agreed completely, with no inter-observer discordance. Conclusion: The number of vertebrae could be identified consistently by counting caudally from C2 with cross-referencing cervicothoracic and lumbosacral sagittal MRI scans on the PACS workstation

  9. Numbering of vertebrae on MRI using a PACS cross-referencing tool

    Energy Technology Data Exchange (ETDEWEB)

    Paik, Nam Chull [Dept. of Radiology, Arumdaun Wooldul Spine Hospital, Ulsan (Korea, Republic of)], e-mail: srsna@freechal.com; Lim, Chun Soo; Jang, Ho Suk [Dept. of Neurosurgery, Arumdaun Wooldul Spine Hospital, Ulsan (Korea, Republic of)

    2012-09-15

    Background: For the detection and documentation of numeric variations on spine magnetic resonance imaging (MRI), different techniques have previously been introduced. However, these methods require additional special imaging algorithms, software, or devices. We intend to introduce a vertebral numbering method using the existing picture archiving and communication system (PACS) and MRI system. Purpose: To assess the accuracy of a method for numbering presacral vertebrae based on the cross-referencing of two sagittal MRI series. Material and Methods: This study was a retrospective review of 224 consecutive patients who underwent both lumbar MRI with cervicothoracic scan and whole spine radiographic examinations. A radiologist and a neurosurgeon independently counted the number of presacral vertebrae in a cranial-to-caudal approach with cross-referencing of cervicothoracic and lumbar MRI sagittal series on the PACS workstation. Radiographic numbering from the cervical through the thoracic to the lumbar vertebrae, as a reference standard, was completed independently by the two reviewers. An analysis of the inter-observer and intermodality agreements of radiography and MRI was done. Results: In all cases except one, concordant numbering existed between the two modalities of MRI cross-referencing and radiographs combination. Both observers agreed completely, with no inter-observer discordance. Conclusion: The number of vertebrae could be identified consistently by counting caudally from C2 with cross-referencing cervicothoracic and lumbosacral sagittal MRI scans on the PACS workstation.

  10. Potential time savings to radiology department personnel in a PACS-based environment

    Science.gov (United States)

    Saarinen, Allan O.; Wilson, M. C.; Iverson, Scott C.; Loop, John W.

    1990-08-01

    A purported benefit of digital imaging and archiving of radiographic procedures is the presumption of time savings to radiologists, radiology technologists, and radiology departmentpersonnel involved with processingfilms and managing theflimfile room. As part of the University of Washington's evaluation of Picture Archiving and Communication Systems (PACS)for the U.S. Army Medical Research and Development Command, a study was performed which evaluated the current operationalpractices of the film-based radiology department at the University of Washington Medical Center (UWMC). Industrial engineering time and motion studies were conducted to document the length of time requiredforfilm processing in various modalities, the proportion of the total exam time usedforfilm processing, the amount of time radiologists spent searchingfor and looking at images, and the amount of time file room personnel spent collating reports, making loans, updatingfilm jacket information, and purging files. This evaluation showed that better than one-half of the tasks in the file room may be eliminated with PACS and radiologists may save easily 10 percent of the time they spend reading films by no longer having to searchforfilms. Radiology technologists may also save as much as 10 percent of their time with PACS, although this estimate is subject to significant patient mix aberrations and measurement error. Given that the UWMC radiology department operates efficiently, similar improvements are forecast for other radiology departments and larger improvements areforecastfor less efficient departments.

  11. Optimizing physicians' instruction of PACS through e-learning: cognitive load theory applied.

    Science.gov (United States)

    Devolder, P; Pynoo, B; Voet, T; Adang, L; Vercruysse, J; Duyck, P

    2009-03-01

    This article outlines the strategy used by our hospital to maximize the knowledge transfer to referring physicians on using a picture archiving and communication system (PACS). We developed an e-learning platform underpinned by the cognitive load theory (CLT) so that in depth knowledge of PACS' abilities becomes attainable regardless of the user's prior experience with computers. The application of the techniques proposed by CLT optimizes the learning of the new actions necessary to obtain and manipulate radiological images. The application of cognitive load reducing techniques is explained with several examples. We discuss the need to safeguard the physicians' main mental processes to keep the patient's interests in focus. A holistic adoption of CLT techniques both in teaching and in configuration of information systems could be adopted to attain this goal. An overview of the advantages of this instruction method is given both on the individual and organizational level.

  12. The VISTA ZYJHKs photometric system: calibration from 2MASS

    Science.gov (United States)

    González-Fernández, C.; Hodgkin, S. T.; Irwin, M. J.; González-Solares, E.; Koposov, S. E.; Lewis, J. R.; Emerson, J. P.; Hewett, P. C.; Yoldaş, A. K.; Riello, M.

    2018-03-01

    In this paper, we describe the routine photometric calibration of data taken with the VISTA infrared camera (VIRCAM) instrument on the ESO Visible and Infrared Survey Telescope for Astronomy (VISTA) telescope. The broad-band ZYJHKs data are directly calibrated from Two Micron all Sky Survey (2MASS) point sources visible in every VISTA image. We present the empirical transformations between the 2MASS and VISTA, and Wide-Field Camera and VISTA, photometric systems for regions of low reddening. We investigate the long-term performance of VISTA+VIRCAM. An investigation of the dependence of the photometric calibration on interstellar reddening leads to these conclusions: (1) For all broad-band filters, a linear colour-dependent correction compensates the gross effects of reddening where E(B - V) < 5.0. (2) For Z and Y, there is a significantly larger scatter above E(B - V) = 5.0, and insufficient measurements to adequately constrain the relation beyond this value. (3) The JHKs filters can be corrected to a few per cent up to E(B - V) = 10.0. We analyse spatial systematics over month-long time-scales, both inter- and intradetector and show that these are present only at very low levels in VISTA. We monitor and remove residual detector-to-detector offsets. We compare the calibration of the main pipeline products: pawprints and tiles. We show how variable seeing and transparency affect the final calibration accuracy of VISTA tiles, and discuss a technique, grouting, for mitigating these effects. Comparison between repeated reference fields is used to demonstrate that the VISTA photometry is precise to better than ≃ 2 per cent for the YJHKs bands and 3 per cent for the Z bands. Finally, we present empirically determined offsets to transform VISTA magnitudes into a true Vega system.

  13. On the realistic validation of photometric redshifts

    DEFF Research Database (Denmark)

    Beck, R.; Lin, C. A.; Ishida, E. E.O.

    2017-01-01

    test of photo-z methods. Using photometry from the Sloan Digital Sky Survey and spectroscopy from a collection of sources, we constructed data sets that mimic the biases between the underlying probability distribution of the real spectroscopic and photometric sample. We demonstrate the potential...

  14. Interstellar Extinction in the Gaia Photometric Systems

    Directory of Open Access Journals (Sweden)

    Bridžius A.

    2003-12-01

    Full Text Available Three medium-band photometric systems proposed for the Gaia space mission are intercompared in determining color excesses for stars of spectral classes from O to M at V = 18 mag. A possibility of obtaining a three-dimensional map of the interstellar extinction is discussed.

  15. Photometric study of uranyl-terramycin complex

    Energy Technology Data Exchange (ETDEWEB)

    Sankara Reddy, P B [Government Coll., Cuddapah, Andhra Pradesh (India). Dept. of Chemistry; Reddy, A V.R.; Brahmaji Rao, S [SVU Autonomous Post-Graduate Centre, Anantapur (India). Dept. of Chemistry

    1980-04-01

    The spectrophotometric investigation of uranylterramycin complex in solution has been studied photometrically at pH 1.3. The composition of the complex is established by Job's and Slope ratio methods as 1:1. The stability constant calculated from the data obtained in Job's method is 1.9 x 10/sup 3/. Beer's law is obeyed.

  16. Incremental cost of PACS in a medical intensive care unit

    Science.gov (United States)

    Langlotz, Curtis P.; Cleff, Bridget; Even-Shoshan, Orit; Bozzo, Mary T.; Redfern, Regina O.; Brikman, Inna; Seshadri, Sridhar B.; Horii, Steven C.; Kundel, Harold L.

    1995-05-01

    Our purpose is to determine the incremental costs (or savings) due to the introduction of picture archiving and communication systems (PACS) and computed radiology (CR) in a medical intensive care unit (MICU). Our economic analysis consists of three measurement methods. The first method is an assessment of the direct costs to the radiology department, implemented in a spreadsheet model. The second method consists of a series of brief observational studies to measure potential changes in personnel costs that might not be reflected in administrative claims. The third method (results not reported here) is a multivariate modeling technique which estimates the independent effect of PACS/CR on the cost of care (estimated from administrative claims data), while controlling for clinical case- mix variables. Our direct cost model shows no cost savings to the radiology department after the introduction of PACS in the medical intensive care unit. Savings in film supplies and film library personnel are offset by increases in capital equipment costs and PACS operation personnel. The results of observational studies to date demonstrate significant savings in clinician film-search time, but no significant change in technologist time or lost films. Our model suggests that direct radiology costs will increase after the limited introduction of PACS/CR in the MICU. Our observational studies show a small but significant effect on clinician film search time by the introduction of PACS/CR in the MICU, but no significant effect on other variables. The projected costs of a hospital-wide PACS are currently under study.

  17. Photometric Variability of the Be Star Population

    Energy Technology Data Exchange (ETDEWEB)

    Labadie-Bartz, Jonathan; Pepper, Joshua; McSwain, M. Virginia [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015 (United States); Bjorkman, J. E.; Bjorkman, K. S. [Ritter Observatory, Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft, Toledo, OH 43606-3390 (United States); Lund, Michael B.; Rodriguez, Joseph E.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Stevens, Daniel J. [Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States); James, David J. [Cerro Tololo Inter-American Observatory, Casilla 603 La Serena (Chile); Kuhn, Rudolf B. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Siverd, Robert J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Beatty, Thomas G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2017-06-01

    Be stars have generally been characterized by the emission lines in their spectra, and especially the time variability of those spectroscopic features. They are known to also exhibit photometric variability at multiple timescales, but have not been broadly compared and analyzed by that behavior. We have taken advantage of the advent of wide-field, long-baseline, and high-cadence photometric surveys that search for transiting exoplanets to perform a comprehensive analysis of brightness variations among a large number of known Be stars. The photometric data comes from the KELT transit survey, with a typical cadence of 30 minutes, a baseline of up to 10 years, photometric precision of about 1%, and coverage of about 60% of the sky. We analyze KELT light curves of 610 known Be stars in both the northern and southern hemispheres in an effort to study their variability. Consistent with other studies of Be star variability, we find most of the stars to be photometrically variable. We derive lower limits on the fraction of stars in our sample that exhibit features consistent with non-radial pulsations (25%), outbursts (36%), and long-term trends in the circumstellar disk (37%), and show how these are correlated with spectral sub-types. Other types of variability, such as those owing to binarity, are also explored. Simultaneous spectroscopy for some of these systems from the Be Star Spectra database allow us to better understand the physical causes for the observed variability, especially in cases of outbursts and changes in the disk.

  18. Photometric Variability of the Be Star Population

    International Nuclear Information System (INIS)

    Labadie-Bartz, Jonathan; Pepper, Joshua; McSwain, M. Virginia; Bjorkman, J. E.; Bjorkman, K. S.; Lund, Michael B.; Rodriguez, Joseph E.; Stassun, Keivan G.; Stevens, Daniel J.; James, David J.; Kuhn, Rudolf B.; Siverd, Robert J.; Beatty, Thomas G.

    2017-01-01

    Be stars have generally been characterized by the emission lines in their spectra, and especially the time variability of those spectroscopic features. They are known to also exhibit photometric variability at multiple timescales, but have not been broadly compared and analyzed by that behavior. We have taken advantage of the advent of wide-field, long-baseline, and high-cadence photometric surveys that search for transiting exoplanets to perform a comprehensive analysis of brightness variations among a large number of known Be stars. The photometric data comes from the KELT transit survey, with a typical cadence of 30 minutes, a baseline of up to 10 years, photometric precision of about 1%, and coverage of about 60% of the sky. We analyze KELT light curves of 610 known Be stars in both the northern and southern hemispheres in an effort to study their variability. Consistent with other studies of Be star variability, we find most of the stars to be photometrically variable. We derive lower limits on the fraction of stars in our sample that exhibit features consistent with non-radial pulsations (25%), outbursts (36%), and long-term trends in the circumstellar disk (37%), and show how these are correlated with spectral sub-types. Other types of variability, such as those owing to binarity, are also explored. Simultaneous spectroscopy for some of these systems from the Be Star Spectra database allow us to better understand the physical causes for the observed variability, especially in cases of outbursts and changes in the disk.

  19. PacCYP707A2 negatively regulates cherry fruit ripening while PacCYP707A1 mediates drought tolerance.

    Science.gov (United States)

    Li, Qian; Chen, Pei; Dai, Shengjie; Sun, Yufei; Yuan, Bing; Kai, Wenbin; Pei, Yuelin; He, Suihuan; Liang, Bin; Zhang, Yushu; Leng, Ping

    2015-07-01

    Sweet cherry is a non-climacteric fruit and its ripening is regulated by abscisic acid (ABA) during fruit development. In this study, four cDNAs (PacCYP707A1-4) encoding 8'-hydroxylase, a key enzyme in the oxidative catabolism of ABA, were identified in sweet cherry fruits using tobacco rattle virus-induced gene silencing (VIGS) and particle bombardment approaches. Quantitative real-time PCR confirmed significant down-regulation of target gene transcripts in VIGS-treated cherry fruits. In PacCYP707A2-RNAi-treated fruits, ripening and fruit colouring were promoted relative to control fruits, and both ABA accumulation and PacNCED1 transcript levels were up-regulated by 140%. Silencing of PacCYP707A2 by VIGS significantly altered the transcripts of both ABA-responsive and ripening-related genes, including the ABA metabolism-associated genes NCED and CYP707A, the anthocyanin synthesis genes PacCHS, PacCHI, PacF3H, PacDFR, PacANS, and PacUFGT, the ethylene biosynthesis gene PacACO1, and the transcription factor PacMYBA. The promoter of PacMYBA responded more strongly to PacCYP707A2-RNAi-treated fruits than to PacCYP707A1-RNAi-treated fruits. By contrast, silencing of PacCYP707A1 stimulated a slight increase in fruit colouring and enhanced resistance to dehydration stress compared with control fruits. These results suggest that PacCYP707A2 is a key regulator of ABA catabolism that functions as a negative regulator of fruit ripening, while PacCYP707A1 regulates ABA content in response to dehydration during fruit development. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  20. PACS-Graz, 1985-2000: from a scientific pilot to a state-wide multimedia radiological information system

    Science.gov (United States)

    Gell, Guenther

    2000-05-01

    1971/72 began the implementation of a computerized radiological documentation system as the Department of Radiology of the University of Graz, which developed over the years into a full RIS. 1985 started a scientific cooperation with SIEMENS to develop a PACS. The two systems were linked and evolved into a highly integrated RIS-PACS for the state wide hospital system in Styria. During its lifetime the RIS, originally implemented in FORTRAN on a UNIVAC 494 mainframe migrated to a PDP15, on to a PDP11, then VAX and Alphas. The flexible original record structure with variable length fields and the powerful retrieval language were retained. The data acquisition part with the user interface was rewritten several times and many service programs have been added. During our PACS cooperation many ideas like the folder concept or functionalities of the GUI have been designed and tested and were then implemented in the SIENET product. The actual RIS/PACS supports the whole workflow in the Radiology Department. It is installed in a 2.300 bed university hospital and the smaller hospitals of the State of Styria. Modalities from different vendors are connected via DICOM to the RIS (modality worklist) and to the PACS. PACSubsystems from other vendors have been integrated. Images are distributed to referring clinics and for teleconsultation and image processing and reports are available on line to all connected hospitals. We spent great efforts to guarantee optimal support of the workflow and to ensure an enhanced cost/benefit ratio for each user (class). Another special feature is selective image distribution. Using the high level retrieval language individual filters can be constructed easily to implement any image distribution policy agreed upon by radiologists and referring clinicians.

  1. A photometric function of planetary surfaces for gourmets

    Science.gov (United States)

    Shkuratov, Yuriy; Korokhin, Viktor; Shevchenko, Vasilij; Mikhalchenko, Olga; Belskaya, Irina; Kaydash, Vadym; Videen, Gorden; Zubko, Evgenij; Velikodsky, Yuriy

    2018-03-01

    A new photometric model with small number of parameters is presented. The model is based on an assumption that there exist such surfaces for which spatial brightness variations caused by small topography undulations can be reproduced exactly by corresponding spatial variations of albedo. This indistinguishability results in a differential equation suggesting a new photometric function that generalizes, in particular, the Akimov disk-function. Our model provides excellent fits in a wide phase-angle range for integral observations of asteroids of different albedos. We also carried out fitting to integral observations of the Moon and Mercury, confirming difficulties in describing Mercury's phase function at large phase angles, which were also found for the Hapke model. Comparisons of global latitude and longitude trends with our model calculations have shown good coincidence for the Moon. To retrieve the lunar trends, we use the phase-ratio technique, applying it to our telescope observations. Mapping the model parameters using LROC WAC data were carried out for a region comprising the Reiner Gamma formation. This mapping allows us to calculate phase-ratio images of the region, showing at large phase angles systematically steeper phase curves of young craters and smaller steepness for the very Reiner Gamma formation.

  2. USING COLORS TO IMPROVE PHOTOMETRIC METALLICITY ESTIMATES FOR GALAXIES

    International Nuclear Information System (INIS)

    Sanders, N. E.; Soderberg, A. M.; Levesque, E. M.

    2013-01-01

    There is a well known correlation between the mass and metallicity of star-forming galaxies. Because mass is correlated with luminosity, this relation is often exploited, when spectroscopy is not available, to estimate galaxy metallicities based on single band photometry. However, we show that galaxy color is typically more effective than luminosity as a predictor of metallicity. This is a consequence of the correlation between color and the galaxy mass-to-light ratio and the recently discovered correlation between star formation rate (SFR) and residuals from the mass-metallicity relation. Using Sloan Digital Sky Survey spectroscopy of ∼180, 000 nearby galaxies, we derive 'LZC relations', empirical relations between metallicity (in seven common strong line diagnostics), luminosity, and color (in 10 filter pairs and four methods of photometry). We show that these relations allow photometric metallicity estimates, based on luminosity and a single optical color, that are ∼50% more precise than those made based on luminosity alone; galaxy metallicity can be estimated to within ∼0.05-0.1 dex of the spectroscopically derived value depending on the diagnostic used. Including color information in photometric metallicity estimates also reduces systematic biases for populations skewed toward high or low SFR environments, as we illustrate using the host galaxy of the supernova SN 2010ay. This new tool will lend more statistical power to studies of galaxy populations, such as supernova and gamma-ray burst host environments, in ongoing and future wide-field imaging surveys

  3. Patriot PAC-2 Development and Deployment in The Gulf War

    National Research Council Canada - National Science Library

    Sherman, J

    2003-01-01

    .... Patriot PAC-2 is a case study in effective project management that resulted in the extraordinary acceleration in the final stages of development production and deployment in time to play a historic role in the Gulf War...

  4. PacIOOS Nearshore Sensor 06 (NS06): Pohnpei, Micronesia

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The nearshore sensors are part of the Pacific Islands Ocean Observing System (PacIOOS) and are designed to measure a variety of ocean parameters at fixed point...

  5. PacIOOS Nearshore Sensor 08 (NS08): Koror, Palau

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The nearshore sensors are part of the Pacific Islands Ocean Observing System (PacIOOS) and are designed to measure a variety of ocean parameters at fixed point...

  6. PacIOOS Nearshore Sensor 11 (NS11): Saipan, CNMI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The nearshore sensors are part of the Pacific Islands Ocean Observing System (PacIOOS) and are designed to measure a variety of ocean parameters at fixed point...

  7. Reasons for Picture Archiving and Communication System (PACS ...

    African Journals Online (AJOL)

    Tintswalo Brenda Mahlaola

    Background: The Picture Archiving and Communication System (PACS) has led to an in- ... incidents in which sensitive information was intentionally shared via social media. .... confidentiality of electronic data in terms of medical ethics,.

  8. Adoption of PACS by the Department of Veterans Affairs: the past, the present, and future plans

    Science.gov (United States)

    Siegel, Eliot L.; Reiner, Bruce I.; Kuzmak, Peter M.

    2000-05-01

    The diffusion of PACS technology within the Department of Veterans Affairs has followed the 'S' curve transition originally described by Ryan and Gross in 1943. They described a paradigm that describes the diffusion of a new technology into the community. However the rate of adoption of filmless radiology by the VA has been much higher than that of the general healthcare system. This is likely due to the fact that the VA and Department of Defense medical systems are somewhat isolated and independent from other health care systems and are subject to a different rate of diffusion of technology. The early introduction and success of PACS in the VA undoubtedly accelerated its acceptance throughout the system. An additional impetus to the growth of PACS in the VA has been the development of an image management system that has been incorporated into the electronic medical record. The universal use of the VISTA HIS and RIS system throughout the VA and the fact that it was developed 'in-house' as well as its extensive support for DICOM functionality have also played a major role in facilitating the acceptance of Picture Archival and Communication Systems throughout the VA.

  9. Integrating CAD modules in a PACS environment using a wide computing infrastructure.

    Science.gov (United States)

    Suárez-Cuenca, Jorge J; Tilve, Amara; López, Ricardo; Ferro, Gonzalo; Quiles, Javier; Souto, Miguel

    2017-04-01

    The aim of this paper is to describe a project designed to achieve a total integration of different CAD algorithms into the PACS environment by using a wide computing infrastructure. The aim is to build a system for the entire region of Galicia, Spain, to make CAD accessible to multiple hospitals by employing different PACSs and clinical workstations. The new CAD model seeks to connect different devices (CAD systems, acquisition modalities, workstations and PACS) by means of networking based on a platform that will offer different CAD services. This paper describes some aspects related to the health services of the region where the project was developed, CAD algorithms that were either employed or selected for inclusion in the project, and several technical aspects and results. We have built a standard-based platform with which users can request a CAD service and receive the results in their local PACS. The process runs through a web interface that allows sending data to the different CAD services. A DICOM SR object is received with the results of the algorithms stored inside the original study in the proper folder with the original images. As a result, a homogeneous service to the different hospitals of the region will be offered. End users will benefit from a homogeneous workflow and a standardised integration model to request and obtain results from CAD systems in any modality, not dependant on commercial integration models. This new solution will foster the deployment of these technologies in the entire region of Galicia.

  10. Bibliographic database of PACS-related articles from the SPIE literature

    Science.gov (United States)

    Shile, Peter E.; Freiermuth, Jennifer

    1996-05-01

    Publications of the International Society of Optical Engineering (SPIE) contain much of the relevant literature on Picture Archiving and Communications Systems (PACS) and related topics. In fact, many PACS-related articles indexed by the National Library of Medicine contain references to articles published by SPIE. Unfortunately, SPIE publications themselves are not indexed by the National Library of Medicine and thus can not be identified through Medline. The lack of a convenient mechanism for searching the SPIE literature is problematic for researchers in medical imaging. With the recent introduction on SPIE's Internet server of their Abstracts Online service and their In-CiteTM title and author searching software, the SPIE literature has become more accessible. However, the searching process is still a cumbersome and time consuming process, and it is not possible to perform key word searches of manuscript abstracts. In this paper we present results of our work on developing a mechanism to more thoroughly search SPIE publications for PACS-related articles.

  11. HERSCHEL PACS OBSERVATIONS AND MODELING OF DEBRIS DISKS IN THE TUCANA-HOROLOGIUM ASSOCIATION

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, J. K. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Roberge, A. [Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771 (United States); Chen, C. H. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States); Augereau, J.-C.; Menard, F. [UJF - Grenoble 1/CNRS-INSU, Institut de Planetologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Dent, W. R. F. [ALMA, Avda Apoquindo 3846, Piso 19, Edificio Alsacia, Las Condes, Santiago (Chile); Eiroa, C.; Meeus, G. [Dpt. Fisica Teorica, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Krivov, A. V. [Astrophysikalishes Institut, Friedrich-Schiller-Universitaet Jena, Schillergaesschen 2-3, 07745 Jena (Germany); Mathews, G. S. [Institute for Astronomy (IfA), University of Hawaii, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States); Riviere-Marichalar, P. [Centro de Astrobiologia Depto. Astrofisica (CSIC-INTA), POB 78, 28691 Villanueva de la Canada (Spain); Sandell, G., E-mail: jessd@astro.umd.edu [SOFIA-USRA, NASA Ames Research Center, Building N232, Rm. 146, Moffett Field, CA 94035 (United States)

    2012-07-10

    We present Herschel PACS photometry of 17 B- to M-type stars in the 30 Myr old Tucana-Horologium Association. This work is part of the Herschel Open Time Key Programme 'Gas in Protoplanetary Systems'. 6 of the 17 targets were found to have infrared excesses significantly greater than the expected stellar IR fluxes, including a previously unknown disk around HD30051. These six debris disks were fitted with single-temperature blackbody models to estimate the temperatures and abundances of the dust in the systems. For the five stars that show excess emission in the Herschel PACS photometry and also have Spitzer IRS spectra, we fit the data with models of optically thin debris disks with realistic grain properties in order to better estimate the disk parameters. The model is determined by a set of six parameters: surface density index, grain size distribution index, minimum and maximum grain sizes, and the inner and outer radii of the disk. The best-fitting parameters give us constraints on the geometry of the dust in these systems, as well as lower limits to the total dust masses. The HD105 disk was further constrained by fitting marginally resolved PACS 70 {mu}m imaging.

  12. PACS technologies and reliability: are we making things better or worse?

    Science.gov (United States)

    Horii, Steven C.; Redfern, Regina O.; Kundel, Harold L.; Nodine, Calvin F.

    2002-05-01

    In the process of installing picture archiving and communications (PACS) and speech recognition equipment, upgrading it, and working with previously stored digital image information, the authors encountered a number of problems. Examination of these difficulties illustrated the complex nature of our existing systems and how difficult it is, in many cases, to predict the behavior of these systems. This was found to be true even for our relatively small number of interconnected systems. The purpose of this paper is to illustrate some of the principles of understanding complex system interaction through examples from our experience. The work for this paper grew out of a number of studies we had carried out on our PACS over several years. The complex nature of our systems was evaluated through comparison of our operations with known examples of systems in other industries. Three scenarios: a network failure, a system software upgrade, and attempting to read media from an old archive showed that the major systems used in the radiology departments of many healthcare facilities (HIS, RIS, PACS, and speed recognition) are likely to interact in complex and often unpredictable ways. These interactions may be very difficult or impossible to predict, so that some plans should be made to overcome the negative aspects of the problems that result. Failures and problems, often unpredictable ones, are a likely side effect of having multiple information handling and processing systems interconnected and interoperating. Planning to avoid, or at least not be so vulnerable, to such difficulties is an important aspect of systems planning.

  13. Effects of illumination differences on photometric stereo shape-and-albedo-from-shading for precision lunar surface reconstruction

    Science.gov (United States)

    Chung Liu, Wai; Wu, Bo; Wöhler, Christian

    2018-02-01

    Photoclinometric surface reconstruction techniques such as Shape-from-Shading (SfS) and Shape-and-Albedo-from-Shading (SAfS) retrieve topographic information of a surface on the basis of the reflectance information embedded in the image intensity of each pixel. SfS or SAfS techniques have been utilized to generate pixel-resolution digital elevation models (DEMs) of the Moon and other planetary bodies. Photometric stereo SAfS analyzes images under multiple illumination conditions to improve the robustness of reconstruction. In this case, the directional difference in illumination between the images is likely to affect the quality of the reconstruction result. In this study, we quantitatively investigate the effects of illumination differences on photometric stereo SAfS. Firstly, an algorithm for photometric stereo SAfS is developed, and then, an error model is derived to analyze the relationships between the azimuthal and zenith angles of illumination of the images and the reconstruction qualities. The developed algorithm and error model were verified with high-resolution images collected by the Narrow Angle Camera (NAC) of the Lunar Reconnaissance Orbiter Camera (LROC). Experimental analyses reveal that (1) the resulting error in photometric stereo SAfS depends on both the azimuthal and the zenith angles of illumination as well as the general intensity of the images and (2) the predictions from the proposed error model are consistent with the actual slope errors obtained by photometric stereo SAfS using the LROC NAC images. The proposed error model enriches the theory of photometric stereo SAfS and is of significance for optimized lunar surface reconstruction based on SAfS techniques.

  14. The sphere-PAC fuel code 'SPHERE-3'

    International Nuclear Information System (INIS)

    Wallin, H.

    2000-01-01

    Sphere-PAC fuel is an advanced nuclear fuel, in which the cladding tube is filled with small fuel spheres instead of the more usual fuel pellets. At PSI, the irradiation behaviour of sphere-PAC fuel is calculated using the computer code SPHERE-3. The paper describes the present status of the SPHERE-3 code, and some results of the qualification process against experimental data. (author)

  15. The sphere-pac fuel code 'SPHERE-3'

    International Nuclear Information System (INIS)

    Wallin, H.; Nordstroem, L.A.; Hellwig, C.

    2001-01-01

    Sphere-pac fuel is an advanced nuclear fuel, in which the cladding tube is filled with small fuel spheres instead of the more usual fuel pellets. At PSI, the irradiation behaviour of sphere-pac fuel is calculated using the computer code SPHERE-3. The paper describes the present status of the SPHERE-3 code, and some results of the qualification process against experimental data. (author)

  16. Dark Energy Survey Year 1 Results: The Photometric Data Set for Cosmology

    Science.gov (United States)

    Drlica-Wagner, A.; Sevilla-Noarbe, I.; Rykoff, E. S.; Gruendl, R. A.; Yanny, B.; Tucker, D. L.; Hoyle, B.; Carnero Rosell, A.; Bernstein, G. M.; Bechtol, K.; Becker, M. R.; Benoit-Lévy, A.; Bertin, E.; Carrasco Kind, M.; Davis, C.; de Vicente, J.; Diehl, H. T.; Gruen, D.; Hartley, W. G.; Leistedt, B.; Li, T. S.; Marshall, J. L.; Neilsen, E.; Rau, M. M.; Sheldon, E.; Smith, J.; Troxel, M. A.; Wyatt, S.; Zhang, Y.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Banerji, M.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Dietrich, J. P.; Doel, P.; Evrard, A. E.; Fausti Neto, A.; Flaugher, B.; Fosalba, P.; Frieman, J.; García-Bellido, J.; Gerdes, D. W.; Giannantonio, T.; Gschwend, J.; Gutierrez, G.; Honscheid, K.; James, D. J.; Jeltema, T.; Kuehn, K.; Kuhlmann, S.; Kuropatkin, N.; Lahav, O.; Lima, M.; Lin, H.; Maia, M. A. G.; Martini, P.; McMahon, R. G.; Melchior, P.; Menanteau, F.; Miquel, R.; Nichol, R. C.; Ogando, R. L. C.; Plazas, A. A.; Romer, A. K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Smith, M.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Tarle, G.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Zuntz, J.; DES Collaboration

    2018-04-01

    We describe the creation, content, and validation of the Dark Energy Survey (DES) internal year-one cosmology data set, Y1A1 GOLD, in support of upcoming cosmological analyses. The Y1A1 GOLD data set is assembled from multiple epochs of DES imaging and consists of calibrated photometric zero-points, object catalogs, and ancillary data products—e.g., maps of survey depth and observing conditions, star–galaxy classification, and photometric redshift estimates—that are necessary for accurate cosmological analyses. The Y1A1 GOLD wide-area object catalog consists of ∼ 137 million objects detected in co-added images covering ∼ 1800 {\\deg }2 in the DES grizY filters. The 10σ limiting magnitude for galaxies is g=23.4, r=23.2, i=22.5, z=21.8, and Y=20.1. Photometric calibration of Y1A1 GOLD was performed by combining nightly zero-point solutions with stellar locus regression, and the absolute calibration accuracy is better than 2% over the survey area. DES Y1A1 GOLD is the largest photometric data set at the achieved depth to date, enabling precise measurements of cosmic acceleration at z ≲ 1.

  17. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XV. THE PHOTOMETRIC REDSHIFT ESTIMATION FOR BACKGROUND SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Raichoor, A.; Mei, S.; Huertas-Company, M.; Licitra, R. [GEPI, Observatoire de Paris, CNRS, Université Paris Diderot, 61 Avenue de l' Observatoire, F-75014 Paris (France); Erben, T.; Hildebrandt, H. [Argelander-Institut für Astronomie, University of Bonn, Auf dem Hügel 71, D-53121 Bonn (Germany); Ilbert, O.; Boissier, S.; Boselli, A. [Aix Marseille Université, CNRS, Laboratoire d' Astrophysique de Marseille, UMR 7326, F-13388 Marseille (France); Ball, N. M.; Côté, P.; Ferrarese, L.; Gwyn, S. D. J.; Kavelaars, J. J. [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7 (Canada); Chen, Y.-T. [Insitute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China); Cuillandre, J.-C. [Canada-France-Hawaïi Telescope Corporation, Kamuela, HI 96743 (United States); Duc, P. A. [Laboratoire AIM Paris-Saclay, CEA/IRFU/SAp, CNRS/INSU, Université Paris Diderot, F-91191 Gif-sur-Yvette Cedex (France); Durrell, P. R. [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH 44555 (United States); Guhathakurta, P. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Lançon, A., E-mail: anand.raichoor@obspm.fr [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l' Université, F-67000 Strasbourg (France); and others

    2014-12-20

    The Next Generation Virgo Cluster Survey (NGVS) is an optical imaging survey covering 104 deg{sup 2} centered on the Virgo cluster. Currently, the complete survey area has been observed in the u*giz bands and one third in the r band. We present the photometric redshift estimation for the NGVS background sources. After a dedicated data reduction, we perform accurate photometry, with special attention to precise color measurements through point-spread function homogenization. We then estimate the photometric redshifts with the Le Phare and BPZ codes. We add a new prior that extends to i {sub AB} = 12.5 mag. When using the u* griz bands, our photometric redshifts for 15.5 mag ≤ i ≲ 23 mag or z {sub phot} ≲ 1 galaxies have a bias |Δz| < 0.02, less than 5% outliers, a scatter σ{sub outl.rej.}, and an individual error on z {sub phot} that increases with magnitude (from 0.02 to 0.05 and from 0.03 to 0.10, respectively). When using the u*giz bands over the same magnitude and redshift range, the lack of the r band increases the uncertainties in the 0.3 ≲ z {sub phot} ≲ 0.8 range (–0.05 < Δz < –0.02, σ{sub outl.rej} ∼ 0.06, 10%-15% outliers, and z {sub phot.err.} ∼ 0.15). We also present a joint analysis of the photometric redshift accuracy as a function of redshift and magnitude. We assess the quality of our photometric redshifts by comparison to spectroscopic samples and by verifying that the angular auto- and cross-correlation function w(θ) of the entire NGVS photometric redshift sample across redshift bins is in agreement with the expectations.

  18. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XV. THE PHOTOMETRIC REDSHIFT ESTIMATION FOR BACKGROUND SOURCES

    International Nuclear Information System (INIS)

    Raichoor, A.; Mei, S.; Huertas-Company, M.; Licitra, R.; Erben, T.; Hildebrandt, H.; Ilbert, O.; Boissier, S.; Boselli, A.; Ball, N. M.; Côté, P.; Ferrarese, L.; Gwyn, S. D. J.; Kavelaars, J. J.; Chen, Y.-T.; Cuillandre, J.-C.; Duc, P. A.; Durrell, P. R.; Guhathakurta, P.; Lançon, A.

    2014-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is an optical imaging survey covering 104 deg 2 centered on the Virgo cluster. Currently, the complete survey area has been observed in the u*giz bands and one third in the r band. We present the photometric redshift estimation for the NGVS background sources. After a dedicated data reduction, we perform accurate photometry, with special attention to precise color measurements through point-spread function homogenization. We then estimate the photometric redshifts with the Le Phare and BPZ codes. We add a new prior that extends to i AB = 12.5 mag. When using the u* griz bands, our photometric redshifts for 15.5 mag ≤ i ≲ 23 mag or z phot ≲ 1 galaxies have a bias |Δz| < 0.02, less than 5% outliers, a scatter σ outl.rej. , and an individual error on z phot that increases with magnitude (from 0.02 to 0.05 and from 0.03 to 0.10, respectively). When using the u*giz bands over the same magnitude and redshift range, the lack of the r band increases the uncertainties in the 0.3 ≲ z phot ≲ 0.8 range (–0.05 < Δz < –0.02, σ outl.rej ∼ 0.06, 10%-15% outliers, and z phot.err. ∼ 0.15). We also present a joint analysis of the photometric redshift accuracy as a function of redshift and magnitude. We assess the quality of our photometric redshifts by comparison to spectroscopic samples and by verifying that the angular auto- and cross-correlation function w(θ) of the entire NGVS photometric redshift sample across redshift bins is in agreement with the expectations

  19. Application of photometric models to asteroids

    International Nuclear Information System (INIS)

    Bowell, E.; Dominque, D.; Hapke, B.

    1989-01-01

    The way an asteroid or other atmosphereless solar system body varies in brightness in response to changing illumination and viewing geometry depends in a very complicated way on the physical and optical properties of its surface and on its overall shape. The authors summarize the formulation and application of recent photometric models by Hapke and by Lumme and Bowell. In both models, the brightness of a rough and porous surface is parametrized in terms of the optical properties of individual particles, by shadowing between particles, and by the way in which light scattered among collections of particles. Both models succeed in their goal of fitting the observed photometric behavior of a wide variety of bodies, but neither has led to a very complete understanding of the properties of asteroid regoliths, primarily because in most cases the parameters in the present models cannot be adequately constrained by observations of integral brightness alone over a restricted range of phase angles

  20. Stellar physics with the ALHAMBRA photometric system

    International Nuclear Information System (INIS)

    Villegas, T Aparicio; Alfaro, E J; Moles, M; Benítez, N; Perea, J; Olmo, A del; Cristóbal-Hornillos, D; Cervio, M; Delgado, R M González; Márquez, I; Masegosa, J; Prada, F; Cabrera-Caño, J; Fernández-Soto, A; Aguerri, J A L; Cepa, J; Broadhurst, T; Castander, F J; Infante, L; Martínez, V J

    2011-01-01

    The ALHAMBRA photometric system was specifically designed to perform a tomography of the Universe in some selected areas. Although mainly designed for extragalactic purposes, its 20 contiguous, equal-width, medium-band photometric system in the optical wavelength range, shows a great capacity for stellar classification. In this contribution we propose a methodology for stellar classification and physical parameter estimation (T eff , log g, [Fe/H], and color excess E(B – V)) based on 18 independent reddening-free Q-values from the ALHAMBRA photometry. Based on the theoretical Spectral library BaSeL 2.2, and applied to 288 stars from the Next Generation spectral Library (NGSL), we discuss the reliability of the method and its dependence on the extinction law used.

  1. [A combined PACS and Internet information system in a university medical center].

    Science.gov (United States)

    Heiss, D; König, A; Endres, S; Pfluger, T; Pfeifer, K J; Hahn, K

    2000-06-01

    The Department of Radiology at the University Hospital Innenstadt Munich provides all clinical departments of a large university hospital with several radiology units at different locations. During the last four years all units have been fully digitalized with a stepwise installation of a PACS. The PACS also processes images from the Nuclear Medicine Department. As image modalities, archive systems and review workstations, we use devices from multiple vendors, which are integrated into a consistent system using the DICOM standard. The hospital has developed its own RIS and an Internet information system, which provides access to all reports and images from radiology for all clinical departments inside the hospital. Additionally, other clinical information such as laboratory results or ECG examinations are available through the system. After one year of operation, the system succeeded in the clinical routine work as the primary source for radiological reports and images as well as for laboratory values. The advantages of digitalization were, besides reduction of film cost, especially optimizations of work flow with access to digital images from everywhere at any time.

  2. Uncertain Photometric Redshifts with Deep Learning Methods

    Science.gov (United States)

    D'Isanto, A.

    2017-06-01

    The need for accurate photometric redshifts estimation is a topic that has fundamental importance in Astronomy, due to the necessity of efficiently obtaining redshift information without the need of spectroscopic analysis. We propose a method for determining accurate multi-modal photo-z probability density functions (PDFs) using Mixture Density Networks (MDN) and Deep Convolutional Networks (DCN). A comparison with a Random Forest (RF) is performed.

  3. Photometric Properties of Network and Faculae Derived from HMI Data Compensated for Scattered Light

    Energy Technology Data Exchange (ETDEWEB)

    Criscuoli, Serena; Whitney, Taylor [National Solar Observatory, 3665 Discovery Drive, Boulder, CO 80303 (United States); Norton, Aimee [Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA, 94305 (United States)

    2017-10-01

    We report on the photometric properties of faculae and network, as observed in full-disk, scattered-light-corrected images from the Helioseismic Magnetic Imager. We use a Lucy–Richardson deconvolution routine that corrects an image in less than one second. Faculae are distinguished from network through proximity to active regions. This is the first report that full-disk observations, including center-to-limb variations, reproduce the photometric properties of faculae and network observed previously only in sub-arcsecond-resolution; small field-of-view studies, i.e. that network, as defined by distance from active regions, exhibit higher photometric contrasts. Specifically, for magnetic flux values larger than approximately 300 G, the network is brighter than faculae and the contrast differences increase toward the limb, where the network contrast is about twice the facular one. For lower magnetic flux values, network appear darker than faculae. Contrary to reports from previous full-disk observations, we also found that network exhibits a higher center-to-limb variation. Our results are in agreement with reports from simulations that indicate magnetic flux alone is a poor proxy of the photometric properties of magnetic features. We estimate that the contribution of faculae and network to Total Solar Irradiance variability of the current Cycle 24 is overestimated by at least 11%, due to the photometric properties of network and faculae not being recognized as different. This estimate is specific to the method employed in this study to reconstruct irradiance variations, so caution should be paid when extending it to other techniques.

  4. Photometric Properties of Network and Faculae Derived from HMI Data Compensated for Scattered Light

    International Nuclear Information System (INIS)

    Criscuoli, Serena; Whitney, Taylor; Norton, Aimee

    2017-01-01

    We report on the photometric properties of faculae and network, as observed in full-disk, scattered-light-corrected images from the Helioseismic Magnetic Imager. We use a Lucy–Richardson deconvolution routine that corrects an image in less than one second. Faculae are distinguished from network through proximity to active regions. This is the first report that full-disk observations, including center-to-limb variations, reproduce the photometric properties of faculae and network observed previously only in sub-arcsecond-resolution; small field-of-view studies, i.e. that network, as defined by distance from active regions, exhibit higher photometric contrasts. Specifically, for magnetic flux values larger than approximately 300 G, the network is brighter than faculae and the contrast differences increase toward the limb, where the network contrast is about twice the facular one. For lower magnetic flux values, network appear darker than faculae. Contrary to reports from previous full-disk observations, we also found that network exhibits a higher center-to-limb variation. Our results are in agreement with reports from simulations that indicate magnetic flux alone is a poor proxy of the photometric properties of magnetic features. We estimate that the contribution of faculae and network to Total Solar Irradiance variability of the current Cycle 24 is overestimated by at least 11%, due to the photometric properties of network and faculae not being recognized as different. This estimate is specific to the method employed in this study to reconstruct irradiance variations, so caution should be paid when extending it to other techniques.

  5. HyPac french platform on the hydrogen and fuel cells; HyPac plateforme francaise sur l'hydrogene et les piles a combustible

    Energy Technology Data Exchange (ETDEWEB)

    Lucchese, P. [N ' ERGY, 85 - Antigny (France)

    2008-07-01

    HyPac is a french platform on the hydrogen and fuel cells applications, created in 2008. the authors presents the opportunities of the french platform HyPac, the objectives, the participants and the budget. (A.L.B.)

  6. Photometric Defocus Observations of Transiting Extrasolar Planets

    Directory of Open Access Journals (Sweden)

    Tobias C. Hinse

    2015-03-01

    Full Text Available We have carried out photometric follow-up observations of bright transiting extrasolar planets using the CbNUOJ 0.6 m telescope. We have tested the possibility of obtaining high photometric precision by applying the telescope defocus technique, allowing the use of several hundred seconds in exposure time for a single measurement. We demonstrate that this technique is capable of obtaining a root-mean-square scatter of sub-millimagnitude order over several hours for a V ~10 host star, typical for transiting planets detected from ground-based survey facilities. We compared our results with transit observations from a telescope operated in in-focus mode. High photometric precision was obtained due to the collection of a larger amount of photons, resulting in a higher signal compared to other random and systematic noise sources. Accurate telescope tracking is likely to further contribute to lowering systematic noise by exposing the same pixels on the CCD. Furthermore, a longer exposure time helps reduce the effect of scintillation noise which otherwise has a significant effect for small-aperture telescopes operated in in-focus mode. Finally we present the results of modelling four light-curves in which a root-mean-square scatter of 0.70 to 2.3 milli-magnitudes was achieved.

  7. Can Selforganizing Maps Accurately Predict Photometric Redshifts?

    Science.gov (United States)

    Way, Michael J.; Klose, Christian

    2012-01-01

    We present an unsupervised machine-learning approach that can be employed for estimating photometric redshifts. The proposed method is based on a vector quantization called the self-organizing-map (SOM) approach. A variety of photometrically derived input values were utilized from the Sloan Digital Sky Survey's main galaxy sample, luminous red galaxy, and quasar samples, along with the PHAT0 data set from the Photo-z Accuracy Testing project. Regression results obtained with this new approach were evaluated in terms of root-mean-square error (RMSE) to estimate the accuracy of the photometric redshift estimates. The results demonstrate competitive RMSE and outlier percentages when compared with several other popular approaches, such as artificial neural networks and Gaussian process regression. SOM RMSE results (using delta(z) = z(sub phot) - z(sub spec)) are 0.023 for the main galaxy sample, 0.027 for the luminous red galaxy sample, 0.418 for quasars, and 0.022 for PHAT0 synthetic data. The results demonstrate that there are nonunique solutions for estimating SOM RMSEs. Further research is needed in order to find more robust estimation techniques using SOMs, but the results herein are a positive indication of their capabilities when compared with other well-known methods

  8. A GENERAL STUDY OF THE INFLUENCE OF CATASTROPHIC PHOTOMETRIC REDSHIFT ERRORS ON COSMOLOGY WITH COSMIC SHEAR TOMOGRAPHY

    International Nuclear Information System (INIS)

    Hearin, Andrew P.; Zentner, Andrew R.; Ma Zhaoming; Huterer, Dragan

    2010-01-01

    A goal of forthcoming imaging surveys is to use weak gravitational lensing shear measurements to constrain dark energy. A challenge to this program is that redshifts to the lensed, source galaxies must be determined using photometric, rather than spectroscopic, information. We quantify the importance of uncalibrated photometric redshift outliers to the dark energy goals of forthcoming imaging surveys in a manner that does not assume any particular photometric redshift technique or template. In so doing, we provide an approximate blueprint for computing the influence of specific outlier populations on dark energy constraints. We find that outlier populations whose photo-z distributions are tightly localized about a significantly biased redshift must be controlled to a per-galaxy rate of (1-3) x 10 -3 to insure that systematic errors on dark energy parameters are rendered negligible. In the complementary limit, a subset of imaged galaxies with uncalibrated photometric redshifts distributed over a broad range must be limited to fewer than a per-galaxy error rate of F cat ∼ -4 . Additionally, we explore the relative importance of calibrating the photo-z's of a core set of relatively well-understood galaxies as compared to the need to identify potential catastrophic photo-z outliers. We discuss the degradation of the statistical constraints on dark energy parameters induced by excising source galaxies at high- and low-photometric redshifts, concluding that removing galaxies with photometric redshifts z ph ∼> 2.4 and z ph ∼< 0.3 may mitigate damaging catastrophic redshift outliers at a relatively small (∼<20%) cost in statistical error. In an Appendix, we show that forecasts for the degradation in dark energy parameter constraints due to uncertain photometric redshifts depend sensitively on the treatment of the nonlinear matter power spectrum. In particular, previous work using Peacock and Dodds may have overestimated the photo-z calibration requirements of

  9. Utilization of a multimedia PACS workstation for surgical planning of epilepsy

    Science.gov (United States)

    Soo Hoo, Kent; Wong, Stephen T.; Hawkins, Randall A.; Knowlton, Robert C.; Laxer, Kenneth D.; Rowley, Howard A.

    1997-05-01

    Surgical treatment of temporal lobe epilepsy requires the localization of the epileptogenic zone for surgical resection. Currently, clinicians utilize electroencephalography, various neuroimaging modalities, and psychological tests together to determine the location of this zone. We investigate how a multimedia neuroimaging workstation built on top of the UCSF Picture Archiving and Communication System can be used to aid surgical planning of epilepsy and related brain diseases. This usage demonstrates the ability of the workstation to retrieve image and textural data from PACS and other image sources, register multimodality images, visualize and render 3D data sets, analyze images, generate new image and text data from the analysis, and organize all data in a relational database management system.

  10. DES Science Portal: Computing Photometric Redshifts

    Energy Technology Data Exchange (ETDEWEB)

    Gschwend, Julia [LIneA, Rio de Janeiro

    2016-01-01

    An important challenge facing photometric surveys for cosmological purposes, such as the Dark Energy Survey (DES), is the need to produce reliable photometric redshifts (photo-z). The choice of adequate algorithms and configurations and the maintenance of an up-to-date spectroscopic database to build training sets, for example, are challenging tasks when dealing with large amounts of data that are regularly updated and constantly growing. In this paper, we present the first of a series of tools developed by DES, provided as part of the DES Science Portal, an integrated web-based data portal developed to facilitate the scientific analysis of the data, while ensuring the reproducibility of the analysis. We present the DES Science Portal photometric redshift tools, starting from the creation of a spectroscopic sample to training the neural network photo-z codes, to the final estimation of photo-zs for a large photometric catalog. We illustrate this operation by calculating well calibrated photo-zs for a galaxy sample extracted from the DES first year (Y1A1) data. The series of processes mentioned above is run entirely within the Portal environment, which automatically produces validation metrics, and maintains the provenance between the different steps. This system allows us to fine tune the many steps involved in the process of calculating photo-zs, making sure that we do not lose the information on the configurations and inputs of the previous processes. By matching the DES Y1A1 photometry to a spectroscopic sample, we define different training sets that we use to feed the photo-z algorithms already installed at the Portal. Finally, we validate the results under several conditions, including the case of a sample limited to i<22.5 with the color properties close to the full DES Y1A1 photometric data. This way we compare the performance of multiple methods and training configurations. The infrastructure presented here is an effcient way to test several methods of

  11. Effect of powdered activated carbon (PAC) on MBR performance and effluent trihalomethane formation: At the initial stage of PAC addition.

    Science.gov (United States)

    Gao, Yue; Ma, Defang; Yue, Qinyan; Gao, Baoyu; Huang, Xia

    2016-09-01

    In this study, the MBR was used to treat municipal wastewater for reuse. Effects of powdered activated carbon (PAC) addition on MBR system in terms of effluent water quality, trihalomethane (THM) formation and membrane organic fouling tendency of MBR sludge supernatant at the initial stage of PAC addition were investigated. Effects of chlorine dose and contact time on THM formation and speciation were also studied. PAC addition enhanced the removal of organic matters, especially aromatic components, which improved the UV254 removal rate from 34% to 83%. PAC addition greatly reduced the membrane organic fouling tendency of MBR sludge supernatant. PAC addition reduced the MBR effluent trihalomethane formation potential (THMFP) from 351.29 to 241.95μg/L, while increased THM formation reactivity by 42%. PAC addition enhanced the formation of higher toxic bromine-containing THMs. High chlorine dose and contact time resulted in higher THM formation but lower proportion of bromine-containing THMs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Photometric correction for an optical CCD-based system based on the sparsity of an eight-neighborhood gray gradient.

    Science.gov (United States)

    Zhang, Yuzhong; Zhang, Yan

    2016-07-01

    In an optical measurement and analysis system based on a CCD, due to the existence of optical vignetting and natural vignetting, photometric distortion, in which the intensity falls off away from the image center, affects the subsequent processing and measuring precision severely. To deal with this problem, an easy and straightforward method used for photometric distortion correction is presented in this paper. This method introduces a simple polynomial fitting model of the photometric distortion function and employs a particle swarm optimization algorithm to get these model parameters by means of a minimizing eight-neighborhood gray gradient. Compared with conventional calibration methods, this method can obtain the profile information of photometric distortion from only a single common image captured by the optical CCD-based system, with no need for a uniform luminance area source used as a standard reference source and relevant optical and geometric parameters in advance. To illustrate the applicability of this method, numerical simulations and photometric distortions with different lens parameters are evaluated using this method in this paper. Moreover, the application example of temperature field correction for casting billets also demonstrates the effectiveness of this method. The experimental results show that the proposed method is able to achieve the maximum absolute error for vignetting estimation of 0.0765 and the relative error for vignetting estimation from different background images of 3.86%.

  13. Transmission of DICOM 3.0 type MR data to the personal computer in the hospital without PACS

    International Nuclear Information System (INIS)

    Lee, Seon Kyu; Kim, Hak Soo; Hwang, Hee Young; Kim, Ji Hye; Chung, Hyo Sun; Kim, Hyung Sik

    1999-01-01

    To transmit DICOM data to a personal computer in the hospital without PACS, and estimate the usefulness of digital image management and its convenience for physicians through transmitted file size, transmission time and quality of transmitted images. The raw data of three brain MRI and lumbar spine MRI were transmitted from an MR system to a personal computer via Ethernet TCP/IP connection. The file size and transmission time of transmitted images were measured according to the matrix number. Three board-certified radiologists compared the image quality of the transmitted and scanned images. The transmission of DICOM data to the personal computer was successful and the transmitted images and their header information were displayed by various personal computer-based DICOM viewing programs. The file size and transmission time of the 256 and 512 matrix images were 136 Kbyte, 2.17 seconds/slice and 520 Kbyte, 4.37 seconds/slice, respectively. All radiologists regarded the transmitted brain MRI images as superior. One radiologist considered the transmitted lumbar spine MRI images superior, while others decided that the quality of transmitted and scanned images was the same. The transmission of DICOM format image data to a personal computer through an appropriate DICOM receiving program is useful for managing digital images and convenient for physicians in the hospital without PACS

  14. Effect of PACS/CR on cost of care and length of stay in a medical intensive care unit

    Science.gov (United States)

    Langlotz, Curtis P.; Kundel, Harold L.; Brikman, Inna; Pratt, Hugh M.; Redfern, Regina O.; Horii, Steven C.; Schwartz, J. Sanford

    1996-05-01

    Our purpose was to determine the economic effects associated with the introduction of PACS and computed radiology (CR) in a medical intensive care unit (MICU). Clinical and financial data were collected over a period of 6 months, both before and after the introduction of PACS/CR in our medical intensive care unit. Administrative claims data resulting from the MICU stay of each patient enrolled in our study were transferred online to our research database from the administrative databases of our hospital and its affiliated clinical practices. These data included all charge entries, sociodemographic data, admissions/discharge/transfer chronologies, ICD9 diagnostic and procedure codes, and diagnostic related groups. APACHE III scores and other case mix adjusters were computed from the diagnostic codes, and from the contemporaneous medical record. Departmental charge to cost ratios and the Medicare Resource-Based Relative Value Scale fee schedule were used to estimate costs from hospital and professional charges. Data were analyzed using both the patient and the exam as the unit of analysis. Univariate analyses by patient show that patients enrolled during the PACS periods were similar to those enrolled during the Film periods in age, sex, APACHE III score, and other measures of case mix. No significant differences in unadjusted median length of stay between the two Film and two PACS periods were detected. Likewise, no significant differences in unadjusted total hospital and professional costs were found between the Film and PACS periods. In our univariate analyses by exam, we focused on the subgroup of exams that had triggered primary clinical actions in any period. Those action-triggering exams were divided into two groups according to whether the referring clinician elected to obtain imaging results from the workstation or from the usual channels. Patients whose imaging results were obtain from the workstation had significantly lower professional costs in the 7 days

  15. Increase in productivity by implementation of RIS and PACS throughout a clinic: a case study

    International Nuclear Information System (INIS)

    Nissen-Meyer, S.; Holzknecht, N.; Wieser, B.; Francke, M.; Kuettner, B.; Weber, J.; Reiser, M.; Adelhard, K.; Villain, S.

    2002-01-01

    Problem. How are improvements in productivity in connection with RIS/PACS to be defined? What do they cost? To limit the problem to the relevant topics, we first describe the objectives of a radiology department and the identified bottlenecks in the workflow. How to define and assess the improvements is discussed.Methods. The case in question for this study is the RIS/PACS project at the ''Klinikum der Universitaet Muenchen, Campus Grosshadern''. The goals of the project and its present status are reviewed. The project is not yet completed, so this is a ''midterm'' report.Results and discussion. We describe the status of the achieved and not yet achieved goals and of the eliminated bottlenecks. On the plus side, for example, nearly 100% of all digitally generated images (except mammogramms) are digitally archived. They are accessible to the same percentage in radiology via PACS and in the hospital via the webbased intranet image distribution system when needed. In some radiology areas, such as multislice CT, already the reporting can no longer be performed without softcopy image interpretation. However, the full elimination of hardcopy images is still not reality, since the distribution to DICOM viewers for selected requesters with demands for almost reporting quality, high cost image displays is still in the testphase. To reduce film costs, images are being printed on a high resolution paper printer in addition to the intranet distribution during this transition period. On the negative side, due to a lack of job positions in the transcription rooms, about 40% of the reports are still being handwritten by radiologists. Furthermore, the dictated and transcribed reports are usually still not available early enough in the RIS and thereby in the intranet report distribution of the hospital. Here only a speech recognition system can remedy the situation. As soon as this problem is solved and the image distribution to the DICOM viewers works routinely, the reports and

  16. Photometric Exoplanet Characterization and Multimedia Astronomy Communication

    Science.gov (United States)

    Cartier, Kimberly M. S.

    The transit method of detecting exoplanets has dominated the search for distant worlds since the success of the Kepler space telescope and will continue to lead the field after the launch of the Transiting Exoplanet Survey Satellite in 2018. But detections are just the beginning. Transit light curves can only reveal a limited amount of information about a planet, and that information is almost entirely dependent on the properties of the host star or stars. This dissertation discusses follow-up techniques to more precisely characterize transiting planets using photometric observations. A high-resolution follow-up imaging program using the Hubble Space Telescope (HST) searched for previously unknown stars nearby the hosts of small and cool Kepler exoplanets and observed a higher-than-expected occurrence rate of stellar multiplicity. The rate of previously unknown stellar multiples has strong implications for the size and habitability of the orbiting planets. Three systems with newly discovered stellar multiplicity, Kepler-296 (2 stars, 5 planets), KOI-2626 (3 stars, 1 planet), and KOI-3049 (2 stars, 1 planet), were characterized in more detail. In the cases of Kepler-296 and KOI-2626, some of the planets lost their previous habitable zone status because of host star ambiguity. Next, the ultra-short period, ultra-hot Jupiter WASP-103b was used as a casestudy to test for the presence of a stratospheric temperature inversion through dayside emission spectroscopy using HST. WASP-103b's near-infrared emission spectrum is consistent with an isothermal or thermally-inverted atmosphere and shows no significant broadband water absorption feature. Detection of an anomalously strong "super- Rayleigh" slope in its optical transmission spectrum prompted follow-up transmission spectroscopy of WASP-103b's atmosphere using the MINiature Radial Velocity Array (MINERVA), which tentatively verified the unexplained "super-Rayleigh" spectral slope. The final follow-up technique for

  17. Fully automated processing of fMRI data in SPM: from MRI scanner to PACS.

    Science.gov (United States)

    Maldjian, Joseph A; Baer, Aaron H; Kraft, Robert A; Laurienti, Paul J; Burdette, Jonathan H

    2009-01-01

    Here we describe the Wake Forest University Pipeline, a fully automated method for the processing of fMRI data using SPM. The method includes fully automated data transfer and archiving from the point of acquisition, real-time batch script generation, distributed grid processing, interface to SPM in MATLAB, error recovery and data provenance, DICOM conversion and PACS insertion. It has been used for automated processing of fMRI experiments, as well as for the clinical implementation of fMRI and spin-tag perfusion imaging. The pipeline requires no manual intervention, and can be extended to any studies requiring offline processing.

  18. 3D-HST WFC3-SELECTED PHOTOMETRIC CATALOGS IN THE FIVE CANDELS/3D-HST FIELDS: PHOTOMETRY, PHOTOMETRIC REDSHIFTS, AND STELLAR MASSES

    Energy Technology Data Exchange (ETDEWEB)

    Skelton, Rosalind E. [South African Astronomical Observatory, PO Box 9, Observatory, Cape Town 7935 (South Africa); Whitaker, Katherine E. [Astrophysics Science Division, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Momcheva, Ivelina G.; Van Dokkum, Pieter G.; Bezanson, Rachel; Leja, Joel; Nelson, Erica J.; Oesch, Pascal [Department of Astronomy, Yale University, 260 Whitney Avenue, New Haven, CT 06511 (United States); Brammer, Gabriel B. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Labbé, Ivo; Franx, Marijn; Fumagalli, Mattia [Leiden Observatory, Leiden University, Leiden (Netherlands); Van der Wel, Arjen; Da Cunha, Elisabete; Maseda, Michael V. [Max Planck Institute for Astronomy (MPIA), Königstuhl 17, D-69117, Heidelberg (Germany); Förster Schreiber, Natascha [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Kriek, Mariska [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Lundgren, Britt F. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Magee, Daniel [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA (United States); Marchesini, Danilo, E-mail: ros@saao.ac.za [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); and others

    2014-10-01

    The 3D-HST and CANDELS programs have provided WFC3 and ACS spectroscopy and photometry over ≈900 arcmin{sup 2} in five fields: AEGIS, COSMOS, GOODS-North, GOODS-South, and the UKIDSS UDS field. All these fields have a wealth of publicly available imaging data sets in addition to the Hubble Space Telescope (HST) data, which makes it possible to construct the spectral energy distributions (SEDs) of objects over a wide wavelength range. In this paper we describe a photometric analysis of the CANDELS and 3D-HST HST imaging and the ancillary imaging data at wavelengths 0.3-8 μm. Objects were selected in the WFC3 near-IR bands, and their SEDs were determined by carefully taking the effects of the point-spread function in each observation into account. A total of 147 distinct imaging data sets were used in the analysis. The photometry is made available in the form of six catalogs: one for each field, as well as a master catalog containing all objects in the entire survey. We also provide derived data products: photometric redshifts, determined with the EAZY code, and stellar population parameters determined with the FAST code. We make all the imaging data that were used in the analysis available, including our reductions of the WFC3 imaging in all five fields. 3D-HST is a spectroscopic survey with the WFC3 and ACS grisms, and the photometric catalogs presented here constitute a necessary first step in the analysis of these grism data. All the data presented in this paper are available through the 3D-HST Web site (http://3dhst.research.yale.edu)

  19. 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts, and Stellar Masses

    Science.gov (United States)

    Skelton, Rosalind E.; Whitaker, Katherine E.; Momcheva, Ivelina G.; Brammer, Gabriel B.; van Dokkum, Pieter G.; Labbé, Ivo; Franx, Marijn; van der Wel, Arjen; Bezanson, Rachel; Da Cunha, Elisabete; Fumagalli, Mattia; Förster Schreiber, Natascha; Kriek, Mariska; Leja, Joel; Lundgren, Britt F.; Magee, Daniel; Marchesini, Danilo; Maseda, Michael V.; Nelson, Erica J.; Oesch, Pascal; Pacifici, Camilla; Patel, Shannon G.; Price, Sedona; Rix, Hans-Walter; Tal, Tomer; Wake, David A.; Wuyts, Stijn

    2014-10-01

    The 3D-HST and CANDELS programs have provided WFC3 and ACS spectroscopy and photometry over ≈900 arcmin2 in five fields: AEGIS, COSMOS, GOODS-North, GOODS-South, and the UKIDSS UDS field. All these fields have a wealth of publicly available imaging data sets in addition to the Hubble Space Telescope (HST) data, which makes it possible to construct the spectral energy distributions (SEDs) of objects over a wide wavelength range. In this paper we describe a photometric analysis of the CANDELS and 3D-HST HST imaging and the ancillary imaging data at wavelengths 0.3-8 μm. Objects were selected in the WFC3 near-IR bands, and their SEDs were determined by carefully taking the effects of the point-spread function in each observation into account. A total of 147 distinct imaging data sets were used in the analysis. The photometry is made available in the form of six catalogs: one for each field, as well as a master catalog containing all objects in the entire survey. We also provide derived data products: photometric redshifts, determined with the EAZY code, and stellar population parameters determined with the FAST code. We make all the imaging data that were used in the analysis available, including our reductions of the WFC3 imaging in all five fields. 3D-HST is a spectroscopic survey with the WFC3 and ACS grisms, and the photometric catalogs presented here constitute a necessary first step in the analysis of these grism data. All the data presented in this paper are available through the 3D-HST Web site (http://3dhst.research.yale.edu).

  20. 3D-HST WFC3-SELECTED PHOTOMETRIC CATALOGS IN THE FIVE CANDELS/3D-HST FIELDS: PHOTOMETRY, PHOTOMETRIC REDSHIFTS, AND STELLAR MASSES

    International Nuclear Information System (INIS)

    Skelton, Rosalind E.; Whitaker, Katherine E.; Momcheva, Ivelina G.; Van Dokkum, Pieter G.; Bezanson, Rachel; Leja, Joel; Nelson, Erica J.; Oesch, Pascal; Brammer, Gabriel B.; Labbé, Ivo; Franx, Marijn; Fumagalli, Mattia; Van der Wel, Arjen; Da Cunha, Elisabete; Maseda, Michael V.; Förster Schreiber, Natascha; Kriek, Mariska; Lundgren, Britt F.; Magee, Daniel; Marchesini, Danilo

    2014-01-01

    The 3D-HST and CANDELS programs have provided WFC3 and ACS spectroscopy and photometry over ≈900 arcmin 2 in five fields: AEGIS, COSMOS, GOODS-North, GOODS-South, and the UKIDSS UDS field. All these fields have a wealth of publicly available imaging data sets in addition to the Hubble Space Telescope (HST) data, which makes it possible to construct the spectral energy distributions (SEDs) of objects over a wide wavelength range. In this paper we describe a photometric analysis of the CANDELS and 3D-HST HST imaging and the ancillary imaging data at wavelengths 0.3-8 μm. Objects were selected in the WFC3 near-IR bands, and their SEDs were determined by carefully taking the effects of the point-spread function in each observation into account. A total of 147 distinct imaging data sets were used in the analysis. The photometry is made available in the form of six catalogs: one for each field, as well as a master catalog containing all objects in the entire survey. We also provide derived data products: photometric redshifts, determined with the EAZY code, and stellar population parameters determined with the FAST code. We make all the imaging data that were used in the analysis available, including our reductions of the WFC3 imaging in all five fields. 3D-HST is a spectroscopic survey with the WFC3 and ACS grisms, and the photometric catalogs presented here constitute a necessary first step in the analysis of these grism data. All the data presented in this paper are available through the 3D-HST Web site (http://3dhst.research.yale.edu)

  1. GALAXY ZOO MORPHOLOGY AND PHOTOMETRIC REDSHIFTS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Way, M. J.

    2011-01-01

    It has recently been demonstrated that one can accurately derive galaxy morphology from particular primary and secondary isophotal shape estimates in the Sloan Digital Sky Survey (SDSS) imaging catalog. This was accomplished by applying Machine Learning techniques to the Galaxy Zoo morphology catalog. Using the broad bandpass photometry of the SDSS in combination with precise knowledge of galaxy morphology should help in estimating more accurate photometric redshifts for galaxies. Using the Galaxy Zoo separation for spirals and ellipticals in combination with SDSS photometry we attempt to calculate photometric redshifts. In the best case we find that the root-mean-square error for luminous red galaxies classified as ellipticals is as low as 0.0118. Given these promising results we believe better photometric redshift estimates for all galaxies in the SDSS (∼350 million) will be feasible if researchers can also leverage their derived morphologies via Machine Learning. These initial results look to be promising for those interested in estimating weak lensing, baryonic acoustic oscillation, and other fields dependent upon accurate photometric redshifts.

  2. Business Model for the Security of a Large-Scale PACS, Compliance with ISO/27002:2013 Standard.

    Science.gov (United States)

    Gutiérrez-Martínez, Josefina; Núñez-Gaona, Marco Antonio; Aguirre-Meneses, Heriberto

    2015-08-01

    Data security is a critical issue in an organization; a proper information security management (ISM) is an ongoing process that seeks to build and maintain programs, policies, and controls for protecting information. A hospital is one of the most complex organizations, where patient information has not only legal and economic implications but, more importantly, an impact on the patient's health. Imaging studies include medical images, patient identification data, and proprietary information of the study; these data are contained in the storage device of a PACS. This system must preserve the confidentiality, integrity, and availability of patient information. There are techniques such as firewalls, encryption, and data encapsulation that contribute to the protection of information. In addition, the Digital Imaging and Communications in Medicine (DICOM) standard and the requirements of the Health Insurance Portability and Accountability Act (HIPAA) regulations are also used to protect the patient clinical data. However, these techniques are not systematically applied to the picture and archiving and communication system (PACS) in most cases and are not sufficient to ensure the integrity of the images and associated data during transmission. The ISO/IEC 27001:2013 standard has been developed to improve the ISM. Currently, health institutions lack effective ISM processes that enable reliable interorganizational activities. In this paper, we present a business model that accomplishes the controls of ISO/IEC 27002:2013 standard and criteria of security and privacy from DICOM and HIPAA to improve the ISM of a large-scale PACS. The methodology associated with the model can monitor the flow of data in a PACS, facilitating the detection of unauthorized access to images and other abnormal activities.

  3. A comparison of the time required by radiologists for the preparation of clinico-radiological meetings when film and PACS are used

    International Nuclear Information System (INIS)

    Weatherburn, G.; Bryan, S.; Cousins, C.

    2000-01-01

    The hypothesis was that when a hospital-wide Picture Archive and Communications System (PACS) is used, preparation for clinico-radiological meetings is faster, and more images are available, than when a conventional film system is used. This paper reports a study which compared the preparation time by radiologists when film was used with the time for the same activity when a hospital-wide PACS was used at Hammersmith Hospital for the preparation of the respiratory medicine and hepato-biliary meetings. It was found that when PACS was used the time per patient to prepare for the respiratory medicine session was reduced by 11.1 min and that similarly, 16 min per patient was saved in the preparation of the hepato-biliary sessions. The number of images which were unavailable for the session was reduced when PACS was in operation, but this reduction was not shown to be statistically significant. The introduction of PACS at Hammersmith Hospital has significantly reduced the time spent by radiologists in preparing for the two clinico-radiological sessions studied and, if this is extended to the other numerous sessions held each week, contributes to a considerable saving of staff time within the radiology department. (orig.)

  4. Methodology Of PACS Effectiveness Evaluation As Part Of A Technology Assessment. The Dutch PACS Project Extrapolated.

    Science.gov (United States)

    Andriessen, J. H. T. H.; van der Horst-Bruinsma, I. E.; ter Haar Romeny, B. M.

    1989-05-01

    The present phase of the clinical evaluation within the Dutch PACS project mainly focuses on the development and evaluation of a PACSystem for a few departments in the Utrecht University hospital (UUH). A report on the first clinical experiences and a detailed cost/savings analysis of the PACSystem in the UUH are presented elsewhere. However, an assessment of the wider fmancial and organizational implications for hospitals and for the health sector is also needed. To this end a model for (financial) cost assessment of PACSystems is being developed by BAZIS. Learning from the actual pilot implementation in UUH we realized that general Technology Assessment (TA) also calls for an extra-polation of the medical and organizational effects. After a short excursion into the various approaches towards TA, this paper discusses the (inter) organizational dimensions relevant to the development of the necessary exttapolationmodels.

  5. A contribution to the study of plasmas. An ultra rapid photometric camera

    International Nuclear Information System (INIS)

    Alpern, Marc R.

    1971-01-01

    The limitations of image converters in ultra-rapid photography were discussed, and an electronographic camera designed, to make photometric measurements on plasmas was presented. The electron optics was then studied and the performance attainable, particularly in dynamic operation, was assessed. The experimental facts concerning the interaction between a laser beam and a thin layer of gold was finally established using this camera, the complexity of the mechanism involved in this interaction was shown. (author) [fr

  6. Miniature photometric stereo system for textile surface structure reconstruction

    Science.gov (United States)

    Gorpas, Dimitris; Kampouris, Christos; Malassiotis, Sotiris

    2013-04-01

    In this work a miniature photometric stereo system is presented, targeting the three-dimensional structural reconstruction of various fabric types. This is a supportive module to a robot system, attempting to solve the well known "laundry problem". The miniature device has been designed for mounting onto the robot gripper. It is composed of a low-cost off-the-shelf camera, operating in macro mode, and eight light emitting diodes. The synchronization between image acquisition and lighting direction is controlled by an Arduino Nano board and software triggering. The ambient light has been addressed by a cylindrical enclosure. The direction of illumination is recovered by locating the reflection or the brightest point on a mirror sphere, while a flatfielding process compensates for the non-uniform illumination. For the evaluation of this prototype, the classical photometric stereo methodology has been used. The preliminary results on a large number of textiles are very promising for the successful integration of the miniature module to the robot system. The required interaction with the robot is implemented through the estimation of the Brenner's focus measure. This metric successfully assesses the focus quality with reduced time requirements in comparison to other well accepted focus metrics. Besides the targeting application, the small size of the developed system makes it a very promising candidate for applications with space restrictions, like the quality control in industrial production lines or object recognition based on structural information and in applications where easiness in operation and light-weight are required, like those in the Biomedical field, and especially in dermatology.

  7. Forward Global Photometric Calibration of the Dark Energy Survey

    Science.gov (United States)

    Burke, D. L.; Rykoff, E. S.; Allam, S.; Annis, J.; Bechtol, K.; Bernstein, G. M.; Drlica-Wagner, A.; Finley, D. A.; Gruendl, R. A.; James, D. J.; Kent, S.; Kessler, R.; Kuhlmann, S.; Lasker, J.; Li, T. S.; Scolnic, D.; Smith, J.; Tucker, D. L.; Wester, W.; Yanny, B.; Abbott, T. M. C.; Abdalla, F. B.; Benoit-Lévy, A.; Bertin, E.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; García-Bellido, J.; Gruen, D.; Gutierrez, G.; Honscheid, K.; Kuehn, K.; Kuropatkin, N.; Maia, M. A. G.; March, M.; Marshall, J. L.; Melchior, P.; Menanteau, F.; Miquel, R.; Plazas, A. A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schindler, R.; Sevilla-Noarbe, I.; Smith, M.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Tarle, G.; Walker, A. R.; DES Collaboration

    2018-01-01

    Many scientific goals for the Dark Energy Survey (DES) require the calibration of optical/NIR broadband b = grizY photometry that is stable in time and uniform over the celestial sky to one percent or better. It is also necessary to limit to similar accuracy systematic uncertainty in the calibrated broadband magnitudes due to uncertainty in the spectrum of the source. Here we present a “Forward Global Calibration Method (FGCM)” for photometric calibration of the DES, and we present results of its application to the first three years of the survey (Y3A1). The FGCM combines data taken with auxiliary instrumentation at the observatory with data from the broadband survey imaging itself and models of the instrument and atmosphere to estimate the spatial and time dependences of the passbands of individual DES survey exposures. “Standard” passbands that are typical of the passbands encountered during the survey are chosen. The passband of any individual observation is combined with an estimate of the source spectral shape to yield a magnitude {m}b{std} in the standard system. This “chromatic correction” to the standard system is necessary to achieve subpercent calibrations and in particular, to resolve ambiguity between the broadband brightness of a source and the shape of its SED. The FGCM achieves a reproducible and stable photometric calibration of standard magnitudes {m}b{std} of stellar sources over the multiyear Y3A1 data sample with residual random calibration errors of σ =6{--}7 {mmag} per exposure. The accuracy of the calibration is uniform across the 5000 {\\deg }2 DES footprint to within σ =7 {mmag}. The systematic uncertainties of magnitudes in the standard system due to the spectra of sources are less than 5 {mmag} for main-sequence stars with 0.5< g-i< 3.0.

  8. Forward Global Photometric Calibration of the Dark Energy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Burke, D. L.; Rykoff, E. S.; Allam, S.; Annis, J.; Bechtol, K.; Bernstein, G. M.; Drlica-Wagner, A.; Finley, D. A.; Gruendl, R. A.; James, D. J.; Kent, S.; Kessler, R.; Kuhlmann, S.; Lasker, J.; Li, T. S.; Scolnic, D.; Smith, J.; Tucker, D. L.; Wester, W.; Yanny, B.; Abbott, T. M. C.; Abdalla, F. B.; Benoit-Lévy, A.; Bertin, E.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Doel, P.; Estrada, J.; García-Bellido, J.; Gruen, D.; Gutierrez, G.; Honscheid, K.; Kuehn, K.; Kuropatkin, N.; Maia, M. A. G.; March, M.; Marshall, J. L.; Melchior, P.; Menanteau, F.; Miquel, R.; Plazas, A. A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schindler, R.; Sevilla-Noarbe, I.; Smith, M.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Tarle, G.; Walker, A. R.

    2017-12-28

    Many scientific goals for the Dark Energy Survey (DES) require calibration of optical/NIR broadband $b = grizY$ photometry that is stable in time and uniform over the celestial sky to one percent or better. It is also necessary to limit to similar accuracy systematic uncertainty in the calibrated broadband magnitudes due to uncertainty in the spectrum of the source. Here we present a "Forward Global Calibration Method (FGCM)" for photometric calibration of the DES, and we present results of its application to the first three years of the survey (Y3A1). The FGCM combines data taken with auxiliary instrumentation at the observatory with data from the broad-band survey imaging itself and models of the instrument and atmosphere to estimate the spatial- and time-dependence of the passbands of individual DES survey exposures. "Standard" passbands are chosen that are typical of the passbands encountered during the survey. The passband of any individual observation is combined with an estimate of the source spectral shape to yield a magnitude $m_b^{\\mathrm{std}}$ in the standard system. This "chromatic correction" to the standard system is necessary to achieve sub-percent calibrations. The FGCM achieves reproducible and stable photometric calibration of standard magnitudes $m_b^{\\mathrm{std}}$ of stellar sources over the multi-year Y3A1 data sample with residual random calibration errors of $\\sigma=5-6\\,\\mathrm{mmag}$ per exposure. The accuracy of the calibration is uniform across the $5000\\,\\mathrm{deg}^2$ DES footprint to within $\\sigma=7\\,\\mathrm{mmag}$. The systematic uncertainties of magnitudes in the standard system due to the spectra of sources are less than $5\\,\\mathrm{mmag}$ for main sequence stars with $0.5

  9. A CRITICAL ASSESSMENT OF PHOTOMETRIC REDSHIFT METHODS: A CANDELS INVESTIGATION

    International Nuclear Information System (INIS)

    Dahlen, Tomas; Ferguson, Henry C.; Mobasher, Bahram; Faber, Sandra M.; Barro, Guillermo; Guo, Yicheng; Finkelstein, Steven L.; Finlator, Kristian; Fontana, Adriano; Gruetzbauch, Ruth; Johnson, Seth; Pforr, Janine; Dickinson, Mark E.; Salvato, Mara; Wuyts, Stijn; Wiklind, Tommy; Acquaviva, Viviana; Huang, Jiasheng; Huang, Kuang-Han; Newman, Jeffrey A.

    2013-01-01

    We present results from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) photometric redshift methods investigation. In this investigation, the results from 11 participants, each using a different combination of photometric redshift code, template spectral energy distributions (SEDs), and priors, are used to examine the properties of photometric redshifts applied to deep fields with broadband multi-wavelength coverage. The photometry used includes U-band through mid-infrared filters and was derived using the TFIT method. Comparing the results, we find that there is no particular code or set of template SEDs that results in significantly better photometric redshifts compared to others. However, we find that codes producing the lowest scatter and outlier fraction utilize a training sample to optimize photometric redshifts by adding zero-point offsets, template adjusting, or adding extra smoothing errors. These results therefore stress the importance of the training procedure. We find a strong dependence of the photometric redshift accuracy on the signal-to-noise ratio of the photometry. On the other hand, we find a weak dependence of the photometric redshift scatter with redshift and galaxy color. We find that most photometric redshift codes quote redshift errors (e.g., 68% confidence intervals) that are too small compared to that expected from the spectroscopic control sample. We find that all codes show a statistically significant bias in the photometric redshifts. However, the bias is in all cases smaller than the scatter; the latter therefore dominates the errors. Finally, we find that combining results from multiple codes significantly decreases the photometric redshift scatter and outlier fraction. We discuss different ways of combining data to produce accurate photometric redshifts and error estimates

  10. Panchromatic Hubble Andromeda Treasury. IX. A photometric survey of planetary nebulae in M31

    Energy Technology Data Exchange (ETDEWEB)

    Veyette, Mark J.; Williams, Benjamin F.; Dalcanton, Julianne J.; Balick, Bruce; Fouesneau, Morgan [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Girardi, Léo [Osservatorio Astronomico di Padova—INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Gordon, Karl D.; Kalirai, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Rosenfield, Philip [Department of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell' Osservatorio 3, I-35122 Padova (Italy); Seth, Anil C., E-mail: mveyette@uw.edu [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States)

    2014-09-10

    We search the Hubble Space Telescope (HST) Advanced Camera for Surveys and Wide Field Camera 3 broadband imaging data from the Panchromatic Hubble Andromeda Treasury (PHAT) survey to identify detections of cataloged planetary nebulae (PNs). Of the 711 PNs currently in the literature within the PHAT footprint, we find 467 detected in the broadband. For these 467, we are able to refine their astrometric accuracy from ∼0.''3 to 0.''05. Using the resolution of the HST, we are able to show that 152 objects currently in the catalogs are definitively not PNs, and we show that 32 objects thought to be extended in ground-based images are actually point-like and therefore good PN candidates. We also find one PN candidate that is marginally resolved. If this is a PN, it is up to 0.7 pc in diameter. With our new photometric data, we develop a method of measuring the level of excitation in individual PNs by comparing broadband and narrowband imaging and describe the effects of excitation on a PN's photometric signature. Using the photometric properties of the known PNs in the PHAT catalogs, we search for more PNs, but do not find any new candidates, suggesting that ground-based emission-line surveys are complete in the PHAT footprint to F475W ≅ 24.

  11. A MACHINE-LEARNING METHOD TO INFER FUNDAMENTAL STELLAR PARAMETERS FROM PHOTOMETRIC LIGHT CURVES

    International Nuclear Information System (INIS)

    Miller, A. A.; Bloom, J. S.; Richards, J. W.; Starr, D. L.; Lee, Y. S.; Butler, N. R.; Tokarz, S.; Smith, N.; Eisner, J. A.

    2015-01-01

    A fundamental challenge for wide-field imaging surveys is obtaining follow-up spectroscopic observations: there are >10 9 photometrically cataloged sources, yet modern spectroscopic surveys are limited to ∼few× 10 6 targets. As we approach the Large Synoptic Survey Telescope era, new algorithmic solutions are required to cope with the data deluge. Here we report the development of a machine-learning framework capable of inferring fundamental stellar parameters (T eff , log g, and [Fe/H]) using photometric-brightness variations and color alone. A training set is constructed from a systematic spectroscopic survey of variables with Hectospec/Multi-Mirror Telescope. In sum, the training set includes ∼9000 spectra, for which stellar parameters are measured using the SEGUE Stellar Parameters Pipeline (SSPP). We employed the random forest algorithm to perform a non-parametric regression that predicts T eff , log g, and [Fe/H] from photometric time-domain observations. Our final optimized model produces a cross-validated rms error (RMSE) of 165 K, 0.39 dex, and 0.33 dex for T eff , log g, and [Fe/H], respectively. Examining the subset of sources for which the SSPP measurements are most reliable, the RMSE reduces to 125 K, 0.37 dex, and 0.27 dex, respectively, comparable to what is achievable via low-resolution spectroscopy. For variable stars this represents a ≈12%-20% improvement in RMSE relative to models trained with single-epoch photometric colors. As an application of our method, we estimate stellar parameters for ∼54,000 known variables. We argue that this method may convert photometric time-domain surveys into pseudo-spectrographic engines, enabling the construction of extremely detailed maps of the Milky Way, its structure, and history

  12. Characterization and photometric performance of the Hyper Suprime-Cam Software Pipeline

    Science.gov (United States)

    Huang, Song; Leauthaud, Alexie; Murata, Ryoma; Bosch, James; Price, Paul; Lupton, Robert; Mandelbaum, Rachel; Lackner, Claire; Bickerton, Steven; Miyazaki, Satoshi; Coupon, Jean; Tanaka, Masayuki

    2018-01-01

    The Subaru Strategic Program (SSP) is an ambitious multi-band survey using the Hyper Suprime-Cam (HSC) on the Subaru telescope. The Wide layer of the SSP is both wide and deep, reaching a detection limit of i ˜ 26.0 mag. At these depths, it is challenging to achieve accurate, unbiased, and consistent photometry across all five bands. The HSC data are reduced using a pipeline that builds on the prototype pipeline for the Large Synoptic Survey Telescope. We have developed a Python-based, flexible framework to inject synthetic galaxies into real HSC images, called SynPipe. Here we explain the design and implementation of SynPipe and generate a sample of synthetic galaxies to examine the photometric performance of the HSC pipeline. For stars, we achieve 1% photometric precision at i ˜ 19.0 mag and 6% precision at i ˜ 25.0 in the i band (corresponding to statistical scatters of ˜0.01 and ˜0.06 mag respectively). For synthetic galaxies with single-Sérsic profiles, forced CModel photometry achieves 13% photometric precision at i ˜ 20.0 mag and 18% precision at i ˜ 25.0 in the i band (corresponding to statistical scatters of ˜0.15 and ˜0.22 mag respectively). We show that both forced point spread function and CModel photometry yield unbiased color estimates that are robust to seeing conditions. We identify several caveats that apply to the version of HSC pipeline used for the first public HSC data release (DR1) that need to be taking into consideration. First, the degree to which an object is blended with other objects impacts the overall photometric performance. This is especially true for point sources. Highly blended objects tend to have larger photometric uncertainties, systematically underestimated fluxes, and slightly biased colors. Secondly, >20% of stars at 22.5 21.5 mag.

  13. Influence map baserad Ms. Pac-Man och Ghost Kontroller

    OpenAIRE

    Svensson, Johan

    2012-01-01

    This thesis will cover the use oftheinfluence map technique applied to the retro game Ms. Pac-Man. A game thatis easy to learn but hard to master. The Ms. Pac-Man controller is implemented with five main parameters that alters the behaviour of the controller while the Ghost controller have three parameters. The experimental results of the controllers is explored to using the alterations of the parameters to find its peak of performance. The conclusion from using the influence map for this gam...

  14. HyPac french platform on the hydrogen and fuel cells

    International Nuclear Information System (INIS)

    Lucchese, P.

    2008-01-01

    HyPac is a french platform on the hydrogen and fuel cells applications, created in 2008. the authors presents the opportunities of the french platform HyPac, the objectives, the participants and the budget. (A.L.B.)

  15. LED-based Photometric Stereo: Modeling, Calibration and Numerical Solutions

    DEFF Research Database (Denmark)

    Quéau, Yvain; Durix, Bastien; Wu, Tao

    2018-01-01

    We conduct a thorough study of photometric stereo under nearby point light source illumination, from modeling to numerical solution, through calibration. In the classical formulation of photometric stereo, the luminous fluxes are assumed to be directional, which is very difficult to achieve in pr...

  16. Planck 2013 results. VIII. HFI photometric calibration and mapmaking

    DEFF Research Database (Denmark)

    Planck Collaboration,; Ade, P. A. R.; Aghanim, N.

    2013-01-01

    This paper describes the processing applied to the HFI cleaned time-ordered data to produce photometrically calibrated maps. HFI observes the sky over a broad range of frequencies, from 100 to 857 GHz. To get the best accuracy on the calibration on such a large range, two different photometric ca...

  17. Photometric Variability in the Faint Sky Variability Survey

    NARCIS (Netherlands)

    Morales-Rueda, L.; Groot, P.J.; Augusteijn, T.; Nelemans, G.A.; Vreeswijk, P.M.; Besselaar, E.J.M. van den

    2005-01-01

    The Faint Sky Variability Survey (FSVS) is aimed at finding photometric and/or astrometric variable objects between 16th and 24th mag on time-scales between tens of minutes and years with photometric precisions ranging from 3 millimag to 0.2 mag. An area of ~23 deg2, located at mid and

  18. Distributed PACS using distributed file system with hierarchical meta data servers.

    Science.gov (United States)

    Hiroyasu, Tomoyuki; Minamitani, Yoshiyuki; Miki, Mitsunori; Yokouchi, Hisatake; Yoshimi, Masato

    2012-01-01

    In this research, we propose a new distributed PACS (Picture Archiving and Communication Systems) which is available to integrate several PACSs that exist in each medical institution. The conventional PACS controls DICOM file into one data-base. On the other hand, in the proposed system, DICOM file is separated into meta data and image data and those are stored individually. Using this mechanism, since file is not always accessed the entire data, some operations such as finding files, changing titles, and so on can be performed in high-speed. At the same time, as distributed file system is utilized, accessing image files can also achieve high-speed access and high fault tolerant. The introduced system has a more significant point. That is the simplicity to integrate several PACSs. In the proposed system, only the meta data servers are integrated and integrated system can be constructed. This system also has the scalability of file access with along to the number of file numbers and file sizes. On the other hand, because meta-data server is integrated, the meta data server is the weakness of this system. To solve this defect, hieratical meta data servers are introduced. Because of this mechanism, not only fault--tolerant ability is increased but scalability of file access is also increased. To discuss the proposed system, the prototype system using Gfarm was implemented. For evaluating the implemented system, file search operating time of Gfarm and NFS were compared.

  19. Clinical results of HIS, RIS, PACS integration using data integration CASE tools

    Science.gov (United States)

    Taira, Ricky K.; Chan, Hing-Ming; Breant, Claudine M.; Huang, Lu J.; Valentino, Daniel J.

    1995-05-01

    Current infrastructure research in PACS is dominated by the development of communication networks (local area networks, teleradiology, ATM networks, etc.), multimedia display workstations, and hierarchical image storage architectures. However, limited work has been performed on developing flexible, expansible, and intelligent information processing architectures for the vast decentralized image and text data repositories prevalent in healthcare environments. Patient information is often distributed among multiple data management systems. Current large-scale efforts to integrate medical information and knowledge sources have been costly with limited retrieval functionality. Software integration strategies to unify distributed data and knowledge sources is still lacking commercially. Systems heterogeneity (i.e., differences in hardware platforms, communication protocols, database management software, nomenclature, etc.) is at the heart of the problem and is unlikely to be standardized in the near future. In this paper, we demonstrate the use of newly available CASE (computer- aided software engineering) tools to rapidly integrate HIS, RIS, and PACS information systems. The advantages of these tools include fast development time (low-level code is generated from graphical specifications), and easy system maintenance (excellent documentation, easy to perform changes, and centralized code repository in an object-oriented database). The CASE tools are used to develop and manage the `middle-ware' in our client- mediator-serve architecture for systems integration. Our architecture is scalable and can accommodate heterogeneous database and communication protocols.

  20. Acceptability of picture archiving and communication system (PACS) among hospital healthcare personnel based on a unified theory of acceptance and use of technology.

    Science.gov (United States)

    Ahmadi, Maryam; Mehrabi, Nahid; Sheikhtaheri, Abbas; Sadeghi, Mojtaba

    2017-09-01

    The picture archiving and communication system (PACS) is a healthcare system technology which manages medical images and integrates equipment through a network. There are some theories about the use and acceptance of technology by people to describe the behavior and attitudes of end users towards information technologies. We investigated the influential factors on users' acceptance of PACS in the military hospitals of Tehran. In this applied analytical and cross-sectional study, 151 healthcare employees of military hospitals who had experience in using the PACS system were investigated. Participants were selected by census. The following variables were considered: performance expectancy, efforts expectancy, social influence, facilitating conditions and behavioral intention. Data were gathered using a questionnaire. Its validity and reliability were approved by a panel of experts and was piloted with 30 hospital healthcare staff (Cronbach's alpha =0.91). Spearman correlation coefficient and multiple linear regression analysis were used in analyzing the data. Expected performance, efforts expectancy, social impact and facilitating conditions had a significant relationship with behavioral intention. The multiple regression analysis indicated that only performance expectancy can predict the user's behavioral intentions to use PACS technology. Performance and effort expectancies are quite influential in accepting the use of PACS in hospitals. All healthcare personnel should become aware that using such technology is necessary in a hospital. Knowing the influencing factors that affect the acceptance of using new technology can help in improving its use, especially in a healthcare system. This can improve the offered healthcare services' quality.

  1. Parents as Agents of Change (PAC in pediatric weight management: The protocol for the PAC randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Ball Geoff D C

    2012-08-01

    Full Text Available Abstract Background There is an urgent need to develop and evaluate weight management interventions to address childhood obesity. Recent research suggests that interventions designed for parents exclusively, which have been named parents as agents of change (PAC approaches, have yielded positive outcomes for managing pediatric obesity. To date, no research has combined a PAC intervention approach with cognitive behavioural therapy (CBT to examine whether these combined elements enhance intervention effectiveness. This paper describes the protocol our team is using to examine two PAC-based interventions for pediatric weight management. We hypothesize that children with obesity whose parents complete a CBT-based PAC intervention will achieve greater reductions in adiposity and improvements in cardiometabolic risk factors, lifestyle behaviours, and psychosocial outcomes than children whose parents complete a psycho-education-based PAC intervention (PEP. Methods/Design This study is a pragmatic, two-armed, parallel, single-blinded, superiority, randomized clinical trial. The primary objective is to examine the differential effects of a CBT-based PAC vs PEP-based PAC intervention on children’s BMI z-score (primary outcome. Secondary objectives are to assess intervention-mediated changes in cardiometabolic, lifestyle, and psychosocial variables in children and parents. Both interventions are similar in frequency of contact, session duration, group facilitation, lifestyle behaviour goals, and educational content. However, the interventions differ insofar as the CBT-based intervention incorporates theory-based concepts to help parents link their thoughts, feelings, and behaviours; these cognitive activities are enabled by group leaders who possess formal training in CBT. Mothers and fathers of children (8–12 years of age; BMI ≥85th percentile are eligible to participate if they are proficient in English (written and spoken and agree for at least

  2. Preliminary application in teaching of medical imaging with picture archiving and communication systems

    International Nuclear Information System (INIS)

    Wei Yuqing; Hu Jian; Wang Xuejian; Cao Jun; Tong Juan; Shen Guiquan; Luo Min; Luo Song

    2003-01-01

    Objective: To evaluate PACS (picture archiving and communication systems) in the teaching of medical imaging. Methods: Large screen multimedia reading room and electronic study room were built with GE PACS and Angel RIS (radiology information system) and end-term picture-word work-station. Pictures and words of PACS were unloaded directly for teaching and teaching image bank and test image bank. Results: Large screen multimedia reading room, classroom, and electronic study room were built successfully. Valuable information of nearly 5000 patients in the teaching imaging bank of PACS was accumulated. Classic medical imaging teaching mode was changed. Real-time and multi-mode teaching were realized, and teaching effect was greatly improved. The PACS-based teaching model was accepted pleasantly by students. Conclusion: PACS is very useful to improve the teaching quality of medical imaging and it is worth to popularize

  3. 75 FR 80082 - State, Local, Tribal, And Private Sector Policy Advisory Committee (SLTPS-PAC)

    Science.gov (United States)

    2010-12-21

    ..., Tribal, And Private Sector Policy Advisory Committee (SLTPS-PAC) AGENCY: Information Security Oversight... State, Local, Tribal, and Private Sector Policy Advisory Committee (SLTPS-PAC). The SLTPS-PAC will..., Tribal, and Private Sector Entities, as specified in Executive Order 13549 and its implementing directive...

  4. Experience with PACS in an ATM/Ethernet switched network environment.

    Science.gov (United States)

    Pelikan, E; Ganser, A; Kotter, E; Schrader, U; Timmermann, U

    1998-03-01

    Legacy local area network (LAN) technologies based on shared media concepts are not adequate for the growth of a large-scale picture archiving and communication system (PACS) in a client-server architecture. First, an asymmetric network load, due to the requests of a large number of PACS clients for only a few main servers, should be compensated by communication links to the servers with a higher bandwidth compared to the clients. Secondly, as the number of PACS nodes increases, the network throughout should not measurably cut production. These requirements can easily be fulfilled using switching technologies. Here asynchronous transfer mode (ATM) is clearly one of the hottest topics in networking because the ATM architecture provides integrated support for a variety of communication services, and it supports virtual networking. On the other hand, most of the imaging modalities are not yet ready for integration into a native ATM network. For a lot of nodes already joining an Ethernet, a cost-effective and pragmatic way to benefit from the switching concept would be a combined ATM/Ethernet switching environment. This incorporates an incremental migration strategy with the immediate benefits of high-speed, high-capacity ATM (for servers and high-sophisticated display workstations), while preserving elements of the existing network technologies. In addition, Ethernet switching instead of shared media Ethernet improves the performance considerably. The LAN emulation (LANE) specification by the ATM forum defines mechanisms that allow ATM networks to coexist with legacy systems using any data networking protocol. This paper points out the suitability of this network architecture in accordance with an appropriate system design.

  5. (PACS) data security breaches: Intentional versus non-intentional ...

    African Journals Online (AJOL)

    Background: The Picture Archiving and Communication System (PACS) has led to an increase in breached health records and violation of patient confidentiality. The South African constitution makes provision for human dignity and privacy, virtues which confidentiality seeks to preserve. Confidentiality thus constitutes a ...

  6. Scientific programming on massively parallel processor CP-PACS

    International Nuclear Information System (INIS)

    Boku, Taisuke

    1998-01-01

    The massively parallel processor CP-PACS takes various problems of calculation physics as the object, and it has been designed so that its architecture has been devised to do various numerical processings. In this report, the outline of the CP-PACS and the example of programming in the Kernel CG benchmark in NAS Parallel Benchmarks, version 1, are shown, and the pseudo vector processing mechanism and the parallel processing tuning of scientific and technical computation utilizing the three-dimensional hyper crossbar net, which are two great features of the architecture of the CP-PACS are described. As for the CP-PACS, the PUs based on RISC processor and added with pseudo vector processor are used. Pseudo vector processing is realized as the loop processing by scalar command. The features of the connection net of PUs are explained. The algorithm of the NPB version 1 Kernel CG is shown. The part that takes the time for processing most in the main loop is the product of matrix and vector (matvec), and the parallel processing of the matvec is explained. The time for the computation by the CPU is determined. As the evaluation of the performance, the evaluation of the time for execution, the short vector processing of pseudo vector processor based on slide window, and the comparison with other parallel computers are reported. (K.I.)

  7. First results of Herschel-PACS observations of Neptune

    NARCIS (Netherlands)

    Lellouch, E.; Hartogh, P.; Feuchtgruber, H.; Vandenbussche, B.; de Graauw, Th.; Moreno, R.; Jarchow, C.; Cavalie, T.; Orton, G.; Banaszkiewicz, M.; Blecka, M. I.; Bockelee-Morvan, D.; Crovisier, J.; Encrenaz, T.; Fulton, T.; Kueppers, M.; Lara, L. M.; Lis, D. C.; Medvedev, A. S.; Rengel, M.; Sagawa, H.; Swinyard, B.; Szutowicz, S.; Bensch, F.; Bergin, E.; Billebaud, F.; Biver, N.; Blake, G. A.; Blommaert, J. A. D. L.; Cernicharo, J.; Courtin, R.; Davis, G. R.; Decin, L.; Encrenaz, P.; Gonzalez, A.; Jehin, E.; Kidger, M.; Naylor, D.; Portyankina, G.; Schieder, R.; Sidher, S.; Thomas, N.; de Val-Borro, M.; Verdugo, E.; Waelkens, C.; Aarts, H.; Comito, C.; Kawamura, J. H.; Maestrini, A.; Peacocke, T.; Teipen, R.; Tils, T.; Wildeman, K.; Walker, H.; Blake, G.A.

    2010-01-01

    We report on the initial analysis of a Herschel-PACS full range spectrum of Neptune, covering the 51-220 mu m range with a mean resolving power of similar to 3000, and complemented by a dedicated observation of CH(4) at 120 mu m. Numerous spectral features due to HD (R(0) and R(1)), H(2)O, CH(4),

  8. Photometric properties of type II supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, R [Osservatorio Astrofisico, Asiago (Italy); Trieste Univ. (Italy). Instituto di Matematica); Ciatti, F; Rosino, L [Osservatorio Astrofisico, Asiago (Italy); Pavia Univ. (Italy))

    1979-02-01

    An analysis of the available photometric observations for type II supernovae is presented. The possibility of drawing average curves by the fitting method, as previously done for type I supernovae, is indicated. Two basic shapes have been put into evidence, the first one (2/3 of the objects) is characterized by the presence of a plateau at intermediate phase, the second one by an almost linear decline. Average curves have been also built for the intrinsic color indices. Peculiar cases are discussed, including the unusual objects of types III-IV. The mean absolute magnitude at maximum for type II supernovae has been determined about Msub(B) = -16.45 (sigma=0.78), as a calibration for their use as distance indicators. The distribution in different morphological types and luminosity classes of the parent galaxies is briefly discussed.

  9. Photometrical research geostationary satellite "SBIRS GEO-2"

    Science.gov (United States)

    Sukhov, P. P.; Epishev, V. P; Sukhov, K. P; Kudak, V. I.

    The multicolor photometrical observations GSS "Sbirs Geo-2" were carried in B,V,R filters out during the autumn equinox 2014 and spring 2015 y. Periodic appearance of many light curves and dips of mirror reflections suggests that the GSS was not in orbit in a static position, predetermined three-axis orientation and in dynamic motion. On the basis of computer modeling suggests the following dynamics GSS "Sbirs Geo-2" in orbit. Helically scanning the visible Earth's surface infrared satellite sensors come with period P1 = 15.66 sec. and the rocking of the GSS about the direction of the motion vector of the satellite in orbit with P2 = 62.64 sec., most likely with the purpose to survey the greatest possible portion of the earth's surface.

  10. Robust photometric stereo using structural light sources

    Science.gov (United States)

    Han, Tian-Qi; Cheng, Yue; Shen, Hui-Liang; Du, Xin

    2014-05-01

    We propose a robust photometric stereo method by using structural arrangement of light sources. In the arrangement, light sources are positioned on a planar grid and form a set of collinear combinations. The shadow pixels are detected by adaptive thresholding. The specular highlight and diffuse pixels are distinguished according to their intensity deviations of the collinear combinations, thanks to the special arrangement of light sources. The highlight detection problem is cast as a pattern classification problem and is solved using support vector machine classifiers. Considering the possible misclassification of highlight pixels, the ℓ1 regularization is further employed in normal map estimation. Experimental results on both synthetic and real-world scenes verify that the proposed method can robustly recover the surface normal maps in the case of heavy specular reflection and outperforms the state-of-the-art techniques.

  11. Photometric Lambert Correction for Global Mosaicking of HRSC Data

    Science.gov (United States)

    Walter, Sebastian; Michael, Greg; van Gasselt, Stephan; Kneissl, Thomas

    2015-04-01

    The High Resolution Stereo Camera (HRSC) is a push-broom image sensor onboard Mars Express recording the Martian surface in 3D and color. Being in orbit since 2004, the camera has obtained over 3,600 panchromatic image sequences covering about 70% of the planet's surface at 10-20 m/pixel. The composition of an homogenous global mosaic is a major challenge due to the strong elliptical and highly irregular orbit of the spacecraft, which often results in large variations of illumination and atmospheric conditions between individual images. For the purpose of a global mosaic in the full Nadir resolution of 12.5 m per pixel we present a first-order systematic photometric correction for the individual image sequences based on a Lambertian reflection model. During the radiometric calibration of the HRSC data, values for the reflectance scaling factor and the reflectance offset are added to the individual image labels. These parameters can be used for a linear transformation from the original DN values into spectral reflectance values. The spectral reflectance varies with the solar incidence angle, topography (changing the local incidence angle and therefore adding an exta geometry factor for each ground pixel), the bi-directional reflectance distribution function (BRDF) of the surface, and atmospheric effects. Mosaicking the spectral values together as images sometimes shows large brightness differences. One major contributor to the brightness differences between two images is the differing solar geometry due to the varying time of day when the individual images were obtained. This variation causes two images of the same or adjacent areas to have different image brightnesses. As a first-order correction for the varying illumination conditions and resulting brightness variations, the images are corrected for the solar incidence angle by assuming an ideal diffusely reflecting behaviour of the surface. This correction requires the calculation of the solar geometry for each

  12. THE DISTANCE TO THE MASSIVE GALACTIC CLUSTER WESTERLUND 2 FROM A SPECTROSCOPIC AND HST PHOTOMETRIC STUDY

    International Nuclear Information System (INIS)

    Vargas Álvarez, Carlos A.; Kobulnicky, Henry A.; Bradley, David R.; Kannappan, Sheila J.; Norris, Mark A.; Cool, Richard J.; Miller, Brendan P.

    2013-01-01

    We present a spectroscopic and photometric determination of the distance to the young Galactic open cluster Westerlund 2 using WFPC2 imaging from the Hubble Space Telescope (HST) and ground-based optical spectroscopy. HST imaging in the F336W, F439W, F555W, and F814W filters resolved many sources previously undetected in ground-based observations and yielded photometry for 1136 stars. We identified 15 new O-type stars, along with two probable binary systems, including MSP 188 (O3 + O5.5). We fit reddened spectral energy distributions based on the Padova isochrones to the photometric data to determine individual reddening parameters R V and A V for O-type stars in Wd2. We find average values (R V ) = 3.77 ± 0.09 and (A V ) = 6.51 ± 0.38 mag, which result in a smaller distance than most other spectroscopic and photometric studies. After a statistical distance correction accounting for close unresolved binaries (factor of 1.08), our spectroscopic and photometric data on 29 O-type stars yield that Westerlund 2 has a distance (d) = 4.16 ± 0.07 (random) +0.26 (systematic) kpc. The cluster's age remains poorly constrained, with an upper limit of 3 Myr. Finally, we report evidence of a faint mid-IR polycyclic aromatic hydrocarbon ring surrounding the well-known binary candidate MSP 18, which appears to lie at the center of a secondary stellar grouping within Westerlund 2.

  13. THE DISTANCE TO THE MASSIVE GALACTIC CLUSTER WESTERLUND 2 FROM A SPECTROSCOPIC AND HST PHOTOMETRIC STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Vargas Alvarez, Carlos A.; Kobulnicky, Henry A. [Department of Physics and Astronomy, University of Wyoming, Dept. 3905, Laramie, WY 82071 (United States); Bradley, David R.; Kannappan, Sheila J.; Norris, Mark A. [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, CB 3255, Phillips Hall, Chapel Hill, NC 27599-3255 (United States); Cool, Richard J. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Miller, Brendan P., E-mail: cvargasa@uwyo.edu, E-mail: chipk@uwyo.edu, E-mail: davidbradley512@gmail.com, E-mail: sheila@physics.unc.edu, E-mail: manorris@physics.unc.edu, E-mail: rcool@obs.carnegiescience.edu, E-mail: mbrendan@umich.edu [Department of Astronomy, University of Michigan, 745 Dennison Building, 500 Church St., Ann Arbor, MI 48109 (United States)

    2013-05-15

    We present a spectroscopic and photometric determination of the distance to the young Galactic open cluster Westerlund 2 using WFPC2 imaging from the Hubble Space Telescope (HST) and ground-based optical spectroscopy. HST imaging in the F336W, F439W, F555W, and F814W filters resolved many sources previously undetected in ground-based observations and yielded photometry for 1136 stars. We identified 15 new O-type stars, along with two probable binary systems, including MSP 188 (O3 + O5.5). We fit reddened spectral energy distributions based on the Padova isochrones to the photometric data to determine individual reddening parameters R{sub V} and A{sub V} for O-type stars in Wd2. We find average values (R{sub V} ) = 3.77 {+-} 0.09 and (A{sub V} ) = 6.51 {+-} 0.38 mag, which result in a smaller distance than most other spectroscopic and photometric studies. After a statistical distance correction accounting for close unresolved binaries (factor of 1.08), our spectroscopic and photometric data on 29 O-type stars yield that Westerlund 2 has a distance (d) = 4.16 {+-} 0.07 (random) +0.26 (systematic) kpc. The cluster's age remains poorly constrained, with an upper limit of 3 Myr. Finally, we report evidence of a faint mid-IR polycyclic aromatic hydrocarbon ring surrounding the well-known binary candidate MSP 18, which appears to lie at the center of a secondary stellar grouping within Westerlund 2.

  14. Datafish Multiphase Data Mining Technique to Match Multiple Mutually Inclusive Independent Variables in Large PACS Databases.

    Science.gov (United States)

    Kelley, Brendan P; Klochko, Chad; Halabi, Safwan; Siegal, Daniel

    2016-06-01

    Retrospective data mining has tremendous potential in research but is time and labor intensive. Current data mining software contains many advanced search features but is limited in its ability to identify patients who meet multiple complex independent search criteria. Simple keyword and Boolean search techniques are ineffective when more complex searches are required, or when a search for multiple mutually inclusive variables becomes important. This is particularly true when trying to identify patients with a set of specific radiologic findings or proximity in time across multiple different imaging modalities. Another challenge that arises in retrospective data mining is that much variation still exists in how image findings are described in radiology reports. We present an algorithmic approach to solve this problem and describe a specific use case scenario in which we applied our technique to a real-world data set in order to identify patients who matched several independent variables in our institution's picture archiving and communication systems (PACS) database.

  15. Medical image informatics infrastructure design and applications.

    Science.gov (United States)

    Huang, H K; Wong, S T; Pietka, E

    1997-01-01

    Picture archiving and communication systems (PACS) is a system integration of multimodality images and health information systems designed for improving the operation of a radiology department. As it evolves, PACS becomes a hospital image document management system with a voluminous image and related data file repository. A medical image informatics infrastructure can be designed to take advantage of existing data, providing PACS with add-on value for health care service, research, and education. A medical image informatics infrastructure (MIII) consists of the following components: medical images and associated data (including PACS database), image processing, data/knowledge base management, visualization, graphic user interface, communication networking, and application oriented software. This paper describes these components and their logical connection, and illustrates some applications based on the concept of the MIII.

  16. Filmless PACS in a multiple facility environment

    Science.gov (United States)

    Wilson, Dennis L.; Glicksman, Robert A.; Prior, Fred W.; Siu, Kai-Yeung; Goldburgh, Mitchell M.

    1996-05-01

    A Picture Archiving and Communication System centered on a shared image file server can support a filmless hospital. Systems based on this architecture have proven themselves in over four years of clinical operation. Changes in healthcare delivery are causing radiology groups to support multiple facilities for remote clinic support and consolidation of services. There will be a corresponding need for communicating over a standardized wide area network (WAN). Interactive workflow, a natural extension to the single facility case, requires a means to work effectively and seamlessly across moderate to low speed communication networks. Several schemes for supporting a consortium of medical treatment facilities over a WAN are explored. Both centralized and distributed database approaches are evaluated against several WAN scenarios. Likewise, several architectures for distributing image file servers or buffers over a WAN are explored, along with the caching and distribution strategies that support them. An open system implementation is critical to the success of a wide area system. The role of the Digital Imaging and Communications in Medicine (DICOM) standard in supporting multi- facility and multi-vendor open systems is also addressed. An open system can be achieved by using a DICOM server to provide a view of the system-wide distributed database. The DICOM server interface to a local version of the global database lets a local workstation treat the multiple, distributed data servers as though they were one local server for purposes of examination queries. The query will recover information about the examination that will permit retrieval over the network from the server on which the examination resides. For efficiency reasons, the ability to build cross-facility radiologist worklists and clinician-oriented patient folders is essential. The technologies of the World-Wide-Web can be used to generate worklists and patient folders across facilities. A reliable broadcast

  17. Infrared photometric behavior and opposition effect of Mars

    Science.gov (United States)

    Erard, S.; Bibring, J-P.; Drossart, P.

    1992-01-01

    Although the instrument wasn't designed for this purpose, data from the imaging spectrometer ISM may be used for studying photometric variations of Mars reflectance, that are related to the surface materials and aerosols physical properties. ISM flew aboard the Phobos-2 spacecraft which orbited Mars from January to March, 1989. About 40,000 spectra were acquired in 128 channels ranging from 0.76 to 3.16 micro-m, with a spatial resolution of 25 km and a signal-to-noise ratio ranging up to 1000. Analysis of the results leads to the following conclusions: width variations of the opposition surge can be related to differences in porosity or grain size distribution on the various domains, with little or no effect from suspended dust. As the biggest effects are observed on dark and bright materials, intermediate behaviors on average-bright regions cannot result from a mixing process, but are more likely to come from either cementation processes or modification of the grain size distribution under the influence of wind, which under Martian conditions preferentially removes the biggest particles. Thus, a surface dust consisting in big bright and small dark grains could explain the observations.

  18. The SDSS Coadd: A Galaxy Photometric Redshift Catalog

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Ribamar R.R.; /Fermilab /Rio de Janeiro Federal U.; Soares-Santos, Marcelle; /Fermilab /Inst. Geo. Astron., Havana /Sao Paulo U.; Annis, James; /Fermilab; Dodelson, Scott; /Fermilab /Chicago U. /Chicago U., KICP; Hao, Jiangang; /Fermilab; Johnston, David; /Fermilab; Kubo, Jeffrey; /Fermilab; Lin, Huan; /Fermilab; Seo, Hee-Jong; /UC, Berkeley; Simet, Melanie; /Chicago U.

    2011-11-01

    We present and describe a catalog of galaxy photometric redshifts (photo-z's) for the Sloan Digital Sky Survey (SDSS) Coadd Data. We use the Artificial Neural Network (ANN) technique to calculate photo-z's and the Nearest Neighbor Error (NNE) method to estimate photo-z errors for {approx} 13 million objects classified as galaxies in the coadd with r < 24.5. The photo-z and photo-z error estimators are trained and validated on a sample of {approx} 89, 000 galaxies that have SDSS photometry and spectroscopic redshifts measured by the SDSS Data Release 7 (DR7), the Canadian Network for Observational Cosmology Field Galaxy Survey (CNOC2), the Deep Extragalactic Evolutionary Probe Data Release 3(DEEP2 DR3), the SDSS-III's Baryon Oscillation Spectroscopic Survey (BOSS), the Visible imaging Multi-Object Spectrograph - Very Large Telescope Deep Survey (VVDS) and the WiggleZ Dark Energy Survey. For the best ANN methods we have tried, we find that 68% of the galaxies in the validation set have a photo-z error smaller than {sigma}{sub 68} = 0.036. After presenting our results and quality tests, we provide a short guide for users accessing the public data.

  19. Photometric and Spectral Study of the Saturnian Satellites

    Science.gov (United States)

    Newman, Sarah F.

    2005-01-01

    Photometric and spectra analysis of data from the Cassini Visual and Infrared Mapping Spectrometer (VIMS) has yielded intriguing findings regarding the surface properties of several of the icy Saturnian satellites. Spectral cubes were obtained of these satellites with a wavelength distribution in the IR far more extensive than from any previous observations. Disk-integrated solar phase curves were constructed in several key IR wavelengths that are indicative of key properties of the surface of the body, such as macroscopic roughness, fluffiness (or the porosity of the surface), global albedo and scattering properties of surface particles. Polynomial fits to these phase curves indicate a linear albedo trend of the curvature of the phase functions. Rotational phase functions from Enceladus were found to exhibit a double-peaked sinusoidal curve, which shows larger amplitudes for bands corresponding to water ice and a linear amplitude-albedo trend. These functions indicate regions on the surface of the satellite of more recent geologic activity. In addition, recent images of Enceladus show tectonic features and an absence of impact craters on Southern latitudes which could be indicative of a younger surface. Investigations into the properties of these features using VIMS are underway.

  20. SPLASH-SXDF Multi-wavelength Photometric Catalog

    Science.gov (United States)

    Mehta, Vihang; Scarlata, Claudia; Capak, Peter; Davidzon, Iary; Faisst, Andreas; Hsieh, Bau Ching; Ilbert, Olivier; Jarvis, Matt; Laigle, Clotilde; Phillips, John; Silverman, John; Strauss, Michael A.; Tanaka, Masayuki; Bowler, Rebecca; Coupon, Jean; Foucaud, Sébastien; Hemmati, Shoubaneh; Masters, Daniel; McCracken, Henry Joy; Mobasher, Bahram; Ouchi, Masami; Shibuya, Takatoshi; Wang, Wei-Hao

    2018-04-01

    We present a multi-wavelength catalog in the Subaru/XMM-Newton Deep Field (SXDF) as part of the Spitzer Large Area Survey with Hyper-Suprime-Cam (SPLASH). We include the newly acquired optical data from the Hyper-Suprime-Cam Subaru Strategic Program, accompanied by IRAC coverage from the SPLASH survey. All available optical and near-infrared data is homogenized and resampled on a common astrometric reference frame. Source detection is done using a multi-wavelength detection image including the u-band to recover the bluest objects. We measure multi-wavelength photometry and compute photometric redshifts as well as physical properties for ∼1.17 million objects over ∼4.2 deg2, with ∼800,000 objects in the 2.4 deg2 HSC-Ultra-Deep coverage. Using the available spectroscopic redshifts from various surveys over the range of 0 fraction of 3.2%. The SPLASH-SXDF catalog is a valuable, publicly available resource, perfectly suited for studying galaxies in the early universe and tracing their evolution through cosmic time.

  1. Photometric calibration of the COMBO-17 survey with the Softassign Procrustes Matching method

    Science.gov (United States)

    Sheikhbahaee, Z.; Nakajima, R.; Erben, T.; Schneider, P.; Hildebrandt, H.; Becker, A. C.

    2017-11-01

    Accurate photometric calibration of optical data is crucial for photometric redshift estimation. We present the Softassign Procrustes Matching (SPM) method to improve the colour calibration upon the commonly used Stellar Locus Regression (SLR) method for the COMBO-17 survey. Our colour calibration approach can be categorised as a point-set matching method, which is frequently used in medical imaging and pattern recognition. We attain a photometric redshift precision Δz/(1 + zs) of better than 2 per cent. Our method is based on aligning the stellar locus of the uncalibrated stars to that of a spectroscopic sample of the Sloan Digital Sky Survey standard stars. We achieve our goal by finding a correspondence matrix between the two point-sets and applying the matrix to estimate the appropriate translations in multidimensional colour space. The SPM method is able to find the translation between two point-sets, despite the existence of noise and incompleteness of the common structures in the sets, as long as there is a distinct structure in at least one of the colour-colour pairs. We demonstrate the precision of our colour calibration method with a mock catalogue. The SPM colour calibration code is publicly available at https://neuronphysics@bitbucket.org/neuronphysics/spm.git.

  2. Analysis of optically variable devices using a photometric light-field approach

    Science.gov (United States)

    Soukup, Daniel; Å tolc, Svorad; Huber-Mörk, Reinhold

    2015-03-01

    Diffractive Optically Variable Image Devices (DOVIDs), sometimes loosely referred to as holograms, are popular security features for protecting banknotes, ID cards, or other security documents. Inspection, authentication, as well as forensic analysis of these security features are still demanding tasks requiring special hardware tools and expert knowledge. Existing equipment for such analyses is based either on a microscopic analysis of the grating structure or a point-wise projection and recording of the diffraction patterns. We investigated approaches for an examination of DOVID security features based on sampling the Bidirectional Reflectance Distribution Function (BRDF) of DOVIDs using photometric stereo- and light-field-based methods. Our approach is demonstrated on the practical task of automated discrimination between genuine and counterfeited DOVIDs on banknotes. For this purpose, we propose a tailored feature descriptor which is robust against several expected sources of inaccuracy but still specific enough for the given task. The suggested approach is analyzed from both theoretical as well as practical viewpoints and w.r.t. analysis based on photometric stereo and light fields. We show that especially the photometric method provides a reliable and robust tool for revealing DOVID behavior and authenticity.

  3. A Spectroscopic and Photometric Study of Gravitational Microlensing Events

    Science.gov (United States)

    Kane, Stephen R.

    2000-08-01

    Gravitational microlensing has generated a great deal of scientific interest over recent years. This has been largely due to the realization of its wide-reaching applications, such as the search for dark matter, the detection of planets, and the study of Galactic structure. A significant observational advance has been that most microlensing events can be identified in real-time while the source is still being lensed. More than 400 microlensing events have now been detected towards the Galactic bulge and Magellanic Clouds by the microlensing survey teams EROS, MACHO, OGLE, DUO, and MOA. The real-time detection of these events allows detailed follow-up observations with much denser sampling, both photometrically and spectroscopically. The research undertaken in this project on photometric studies of gravitational microlensing events has been performed as a member of the PLANET (Probing Lensing Anomalies NETwork) collaboration. This is a worldwide collaboration formed in the early part of 1995 to study microlensing anomalies - departures from an achromatic point source, point lens light curve - through rapidly-sampled, multi-band, photometry. PLANET has demonstrated that it can achieve 1% photometry under ideal circumstances, making PLANET observations sensitive to detection of Earth-mass planets which require characterization of 1%--2% deviations from a standard microlensing light curve. The photometric work in this project involved over 5 months using the 1.0 m telescope at Canopus Observatory in Australia, and 3 separate observing runs using the 0.9 m telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile. Methods were developed to reduce the vast amount of photometric data using the image analysis software MIDAS and the photometry package DoPHOT. Modelling routines were then written to analyse a selection of the resulting light curves in order to detect any deviation from an achromatic point source - point lens light curve. The photometric

  4. Photometric Analysis and Period Investigation of the EW Type ...

    Indian Academy of Sciences (India)

    Photometric Analysis and Period Investigation of the EW Type. Eclipsing ... binary with the less massive secondary component filling the inner Roche lobe. ..... Cox 2000) assuming that the primary component is a normal main sequence star.

  5. Experimental Study of RailPAc Plasma Actuator for High-Authority Aerodynamic Flow Control in One Atmosphere

    Science.gov (United States)

    Gray, Miles; Choi, Young-Joon; Raja, Laxminarayan; Sirohi, Jayant

    2014-10-01

    Dielectric barrier discharge (DBD) actuators, a type of electrohydrodynamic (EHD) plasma actuator, have generated considerable interest in recent years. However, theoretical performance limitations hinder their application for high speed flows. Magnetohydrodynamic (MHD) plasma actuators with higher control authority circumvent these limitations, offering an excellent alternative. The rail plasma actuator (RailPAc) is an MHD actuator which uses Lorentz force to impart momentum to the surrounding air. RailPAc functions by generating a fast propagating arc column between two rail electrodes that accelerate the arc through J × B forces in a self-induced B-field. The arc column drags the surrounding air to induce aerodynamic flow motion. Our study of the RailPAc will include a description of the transient arc discharge structure through high-speed imaging and a description of the arc composition and temperature through time-resolved emission spectroscopy. Time-resolved force measurements quantify momentum transfer from the arc to the surrounding air and provides a direct measure of the actuator control authority.

  6. The effects of PACS on radiographer's work practice

    International Nuclear Information System (INIS)

    Larsson, W.; Aspelin, P.; Bergquist, M.; Hillergard, K.; Jacobsson, B.; Lindskoeld, L.; Wallberg, J.; Lundberg, N.

    2007-01-01

    This paper identifies and analyses the effects of picture archiving and communication systems (PACS) on radiographers' work practice. It shows that the introduction of PACS did not simply entail the transfer of data and information from the analogue world to the digital world, but it also led to the introduction of new ways of communicating, and new activities and responsibilities on the part of radiography staff. Radiographers are called upon to work increasingly independently, and individual practitioners require higher levels of professional expertise. In all, this paper demonstrates that new technical solutions sometimes lead to substantial changes in responsibilities in work. In this example, the radiographers' work practice has become more highly scientific and they are enjoying a higher level of prestige

  7. Peligros del átomo pacífico

    Directory of Open Access Journals (Sweden)

    Juan Zarco de Gea

    1962-07-01

    Full Text Available Expuestas en el artículo anterior las ventajas que el hombre puede obtener del uso de la energía atómica para fines pacíficos: industria, agricultura, medicina, investigación científica, etc., parece oportuno examinar ahora el reverso de la medalla y estudiar los inconvenientes de ese mismo uso pacífico de las fuerzas atómicas; inconvenientes, dicho sea de paso, que también existen en el aprovechamiento de otras fuerzas naturales, físicas o químicas, en las minas, fábricas, laboratorios y otras muchas empresas de toda índole; pero tratándose de las energías nucleares entran en juego factores nuevos y especiales, que llevan el asunto a terrenos diferentes: moral, político, de salud pública, etc.

  8. Photometric immersion refractometry of bacterial spores.

    Science.gov (United States)

    Gerhardt, P; Beaman, T C; Corner, T R; Greenamyre, J T; Tisa, L S

    1982-01-01

    Photometric immersion refractometry was used to determine the average apparent refractive index (n) of five types of dormant Bacillus spores representing a 600-fold range in moist-heat resistance determined as a D100 value. The n of a spore type increased as the molecular size of various immersion solutes decreased. For comparison of the spore types, the n of the entire spore and of the isolated integument was determined by use of bovine serum albumin, which is excluded from permeating into them. The n of the sporoplast (the structures bounded by the outer pericortex membrane) was determined by use of glucose, which was shown to permeate into the spore only as deeply as the pericortex membrane. Among the various spore types, an exponential increase in the heat resistance correlated with the n of the entire spore and of the sporoplast, but not of the isolated perisporoplast integument. Correlation of the n with the solids content of the entire spore provided a method of experimentally obtaining the refractive index increment (dn/dc), which was constant for the various spore types and enables the calculation of solids and water content from an n. Altogether, the results showed that the total water content is distributed unequally within the dormant spore, with less water in the sporoplast than in the perisporoplast integument, and that the sporoplast becomes more refractile and therefore more dehydrated as the heat resistance becomes greater among the various spore types. PMID:6802796

  9. Photometric Detection of Extra-Solar Planets

    Science.gov (United States)

    Hatzes, Artie P.; Cochran, William D.

    2004-01-01

    This NASA Origins Program grant supported the TEMPEST Texas McDonald Photometric Extrasolar Search for Transits) program at McDonald Observatory, which searches for transits of extrasolar planets across the disks of their parent stars. The basic approach is to use a wide-field ground-based telescope (in our case the McDonald Observatory 0.76m telescope and it s Prime Focus Corrector) to search for transits of short period (1-15 day orbits) of close-in hot-Jupiter planets in orbit around a large sample of field stars. The next task is to search these data streams for possible transit events. We collected our first set of test data for this program using the 0.76 m PFC in the summer of 1998. From those data, we developed the optimal observing procedures, including tailoring the stellar density, exposure times, and filters to best-suit the instrument and project. In the summer of 1999, we obtained the first partial season of data on a dedicated field in the constellation Cygnus. These data were used to develop and refine the reduction and analysis procedures to produce high-precision photometry and search for transits in the resulting light curves. The TeMPEST project subsequently obtained three full seasons of data on six different fields using the McDonald Observatory 0.76m PFC.

  10. Photometric functions for photoclinometry and other applications

    Science.gov (United States)

    McEwen, A.S.

    1991-01-01

    Least-squared fits to the brightness profiles across a disk or "limb darkening" described by Hapke's photometric function are found for the simpler Minnaert and lunar-Lambert functions. The simpler functions are needed to reduce the number of unknown parameters in photoclinometry, especially to distinguish the brightness variations of the surface materials from that due to the resolved topography. The limb darkening varies with the Hapke parameters for macroscopic roughness (??), the single-scattering albedo (w), and the asymmetry factor of the particle phase function (g). Both of the simpler functions generally provide good matches to the limb darkening described by Hapke's function, but the lunar-Lambert function is superior when viewing angles are high and when (??) is less than 30??. Although a nonunique solution for the Minnaert function at high phase angles has been described for smooth surfaces, the discrepancy decreases with increasing (??) and virtually disappears when (??) reaches 30?? to 40??. The variation in limb darkening with w and g, pronounced for smooth surfaces, is reduced or eliminated when the Hapke parameters are in the range typical of most planetary surfaces; this result simplifies the problem of photoclinometry across terrains with variable surface materials. The Minnaert or lunar-Lambert fits to published Hapke models will give photoclinometric solutions that are very similar (>1?? slope discrepancy) to the Hapke-function solutions for nearly all of the bodies and terrains thus far modeled by Hapke's function. ?? 1991.

  11. Photometric determination of traces of metals

    International Nuclear Information System (INIS)

    Onishi, H.

    1986-01-01

    The first three editions of this widely used classic were published under the title Colorimetric Determination of Traces of Metals, with E.B. Sandell as author. Part I (General Aspects) of the fourth edition was co-authored by E.B. Sandell and H. Onishi and published in 1978. After Sandell's death in 1984, Onishi assumed the monumental task of revising Part II. This book (Part IIA) consists of 21 chapters in which the photometric determinations of the individual metals, aluminium to lithium (including the lanthanoids), are described. Each chapter is divided into three sections: Separations, Methods of Determination, and Applications. The sections on Separations are of general interest and include methods based on precipitation, ion-exchange, chromatography, and liquid-liquid extraction. Molecular absorption and fluorescence techniques are described in the sections on determinations, and the emphasis is on the use of well-established reagents. Several reagents that have been recently introduced for the determination of trace levels of metals are also critically reviewed at the end of each section on methods of determination. Important applications of these methods to the determination of trace metals in complex organic and inorganic materials are described in detail at the end of each chapter

  12. Learning in clinical practice: findings from CT, MRI and PACS

    OpenAIRE

    Sinozic, Tanja

    2014-01-01

    This thesis explores learning in clinical practice in the cases of CT, MRI and PACS in\\ud UK hospitals. It asks the questions of how and why certain evolutionary features of\\ud technology condition learning and change in medical contexts.\\ud Using an evolutionary perspective of cognitive and social aspects of technological\\ud change, this thesis explores the relationships between technology and organisational\\ud learning processes of intuition, interpretation, integration and institutionalisa...

  13. Knowledge barriers to PACS adoption and implementation in hospitals.

    Science.gov (United States)

    Paré, Guy; Trudel, Marie-Claude

    2007-01-01

    Drawing on the classical theory of diffusion of innovations advanced by Rogers [E.M. Rogers, Diffusion of Innovations, 4th ed., Free Press, New York, NY, 1995] and on the theory of barriers to innovation [P. Attewell, Technology diffusion and organizational learning: the case of business computing. Organ. Sci. 3 (1992) 1-19; H. Tanriverdi, C.S. Iacono, Knowledge barriers to diffusion of telemedicine. Proceedings of the 20th International Conference on Information Systems, Charlotte, NC, 1999, pp. 39-50; S. Nambisan, Y.-M. Wang, Roadblocks to web technology adoption? Commun. ACM, 42 (1) (1999) 98-101], this study seeks a better understanding of challenges faced in PACS implementations in hospitals and of the strategies required to ensure their success. To attain this objective, we describe and analyze the process used to adopt and implement PACS at two Canadian hospitals. Our findings clearly demonstrate the importance of treating any PACS deployment not simply as a rollout of new technology but as a project that will transform the organization. Proponents of these projects must not lose sight of the fact that, even if technological complexity represents a significant issue, it must not garner all the project team's attention. This situation is even more dangerous, inasmuch as the greatest risk to the implementation often lies elsewhere. It would also appear to be crucial to anticipate and address organizational and behavioral challenges from the very first phase of the innovation process, in order to ensure that all participants will be committed to the project. In order to maximize the likelihood of PACS success, it appears crucial to adopt a proactive implementation strategy, one that takes into consideration all the technical, economic, organizational, and human factors, and does so from the first phase of the innovation process.

  14. Description and repair procedure for optical digitizers PAC-4

    International Nuclear Information System (INIS)

    Hayat, M.K.; Ahmad, M.S.; Beg, M.M.

    1982-06-01

    The optical digitizer type PAC-4 is an optical analogue-to-digital converter with parallel read out. The optical digitizer is intended for digital measurements of angular rotation of its shaft. In this application the control shaft of the digitizer is coupled to a wheel, which moves on the carriage of the respective spectrometer axes, and indicates its angular position. For accurate determination of the selected neutron energies, it is important to measure the diffraction angles very accurately. (orig./A.B.)

  15. Wilson and Domainwall Kernels on Oakforest-PACS

    Science.gov (United States)

    Kanamori, Issaku; Matsufuru, Hideo

    2018-03-01

    We report the performance of Wilson and Domainwall Kernels on a new Intel Xeon Phi Knights Landing based machine named Oakforest-PACS, which is co-hosted by University of Tokyo and Tsukuba University and is currently fastest in Japan. This machine uses Intel Omni-Path for the internode network. We compare performance with several types of implementation including that makes use of the Grid library. The code is incorporated with the code set Bridge++.

  16. Long-term photometric behaviour of outbursting AM CVn systems

    OpenAIRE

    Levitan, David; Groot, Paul J.; Prince, Thomas A.; Kulkarni, Shrinivas R.; Laher, Russ; Ofek, Eran O.; Sesar, Branimir; Surace, Jason

    2015-01-01

    The AM CVn systems are a class of He-rich, post-period minimum, semidetached, ultracompact binaries. Their long-term light curves have been poorly understood due to the few systems known and the long (hundreds of days) recurrence times between outbursts. We present combined photometric light curves from the Lincoln Near Earth Asteroid Research, Catalina Real-Time Transient Survey, and Palomar Transient Factory synoptic surveys to study the photometric variability of these systems over an almo...

  17. Measuring redshift-space distortions using photometric surveys

    OpenAIRE

    Ross, Ashley; Percival, Will; Crocce, M.; Cabre, A.; Gaztanaga, E.

    2011-01-01

    We outline how redshift-space distortions (RSD) can be measured from the angular correlation function w({\\theta}), of galaxies selected from photometric surveys. The natural degeneracy between RSD and galaxy bias can be minimized by comparing results from bins with top-hat galaxy selection in redshift, and bins based on the radial position of galaxy pair centres. This comparison can also be used to test the accuracy of the photometric redshifts. The presence of RSD will be clearly detectable ...

  18. Intensity measurement of automotive headlamps using a photometric vision system

    Science.gov (United States)

    Patel, Balvant; Cruz, Jose; Perry, David L.; Himebaugh, Frederic G.

    1996-01-01

    Requirements for automotive head lamp luminous intensity tests are introduced. The rationale for developing a non-goniometric photometric test system is discussed. The design of the Ford photometric vision system (FPVS) is presented, including hardware, software, calibration, and system use. Directional intensity plots and regulatory test results obtained from the system are compared to corresponding results obtained from a Ford goniometric test system. Sources of error for the vision system and goniometer are discussed. Directions for new work are identified.

  19. PACS for Bhutan: a cost effective open source architecture for emerging countries.

    Science.gov (United States)

    Ratib, Osman; Roduit, Nicolas; Nidup, Dechen; De Geer, Gerard; Rosset, Antoine; Geissbuhler, Antoine

    2016-10-01

    This paper reports the design and implementation of an innovative and cost-effective imaging management infrastructure suitable for radiology centres in emerging countries. It was implemented in the main referring hospital of Bhutan equipped with a CT, an MRI, digital radiology, and a suite of several ultrasound units. They lacked the necessary informatics infrastructure for image archiving and interpretation and needed a system for distribution of images to clinical wards. The solution developed for this project combines several open source software platforms in a robust and versatile archiving and communication system connected to analysis workstations equipped with a FDA-certified version of the highly popular Open-Source software. The whole system was implemented on standard off-the-shelf hardware. The system was installed in three days, and training of the radiologists as well as the technical and IT staff was provided onsite to ensure full ownership of the system by the local team. Radiologists were rapidly capable of reading and interpreting studies on the diagnostic workstations, which had a significant benefit on their workflow and ability to perform diagnostic tasks more efficiently. Furthermore, images were also made available to several clinical units on standard desktop computers through a web-based viewer. • Open source imaging informatics platforms can provide cost-effective alternatives for PACS • Robust and cost-effective open architecture can provide adequate solutions for emerging countries • Imaging informatics is often lacking in hospitals equipped with digital modalities.

  20. Protecting clinical data in PACS, teleradiology systems, and research environments

    Science.gov (United States)

    Meissner, Marion C.; Collmann, Jeff R.; Tohme, Walid G.; Mun, Seong K.

    1997-05-01

    As clinical data is more widely stored in electronic patient record management systems and transmitted over the Internet and telephone lines, it becomes more accessible and therefore more useful, but also more vulnerable. Computer systems such as PACS, telemedicine applications, and medical research networks must protect against accidental or deliberate modification, disclosure, and violation of patient confidentiality in order to be viable. Conventional wisdom in the medical field and among lawmakers legislating the use of electronic medical records suggests that, although it may improve access to information, an electronic medical record cannot be as secure as a traditional paper record. This is not the case. Information security is a well-developed field in the computer and communications industry. If medical information systems, such as PACS, telemedicine applications, and research networks, properly apply information security techniques, they can ensure the accuracy and confidentiality of their patient information and even improve the security of their data over a traditional paper record. This paper will elaborate on some of these techniques and discuss how they can be applied to medical information systems. The following systems will be used as examples for the analysis: a research laboratory at Georgetown University Medical Center, the Deployable Radiology system installed to support the US Army's peace- keeping operation in Bosnia, a kidney dialysis telemedicine system in Washington, D.C., and various experiences with implementing and integrating PACS.

  1. Removal of a synthetic organic chemical by PAC-UF systems. II: Model application.

    Science.gov (United States)

    Matsui, Y; Colas, F; Yuasa, A

    2001-02-01

    This paper describes several application potentials with a recently developed model for predicting the synthetic organic chemical (SOC) removal by powdered activated carbon (PAC) adsorption during ultrafiltration (UF) and discusses the removal mechanism. The model was successfully applied, without any modification, to dead-end mode operation as well as to cross-flow mode operation, validating the assumption of the internal diffusion control mechanism and the continuously-stirred-tank-reactor (CSTR) concept. Even when UF was operated in a cross-flow mode, PAC added was re-circulating in suspension for only a short time. Then, solute uptake took place mostly by PAC immobilized in membrane tubes not only for dead-end operation but also for cross-flow operation. Therefore, cross-flow operation did not have any advantage regarding the SOC mass transfer on PAC in UF loop over dead-end operation. The model simulation implied that pulse PAC addition at the beginning of filtration cycle resulted better SOC removal than continuous PAC addition. However, for the pulse PAC addition mode, the model predicted somewhat lower effluent SOC concentration than the observed values, and the benefit of pulse PAC application in terms of reducing SOC over its continuous dosage was not confirmed. Longer detention time of PAC dosed in a pulse than continuously dosed PAC could possibly further decrease internal diffusivity.

  2. First experience with the traumatological PACS project at the University of Innsbruck department of Radiology

    International Nuclear Information System (INIS)

    Peer, S.; Peer, R.; Jaschke, W.; Vogl, R.; Baldauf, E.

    1998-01-01

    Radiography in an emergency setting is a demanding task, in technical as well as in logistical terms. Rapid acquisition of high quality radiographs under difficult conditions, for example severely injured patients with multi-organ trauma is important. All image data and radiological reports must be transmitted to the trauma surgeon as soon as possible. To meet these needs with the promising means of modern X-ray technology, we decided to implement a completely digital X-ray division inside the new outpatient trauma department. In the setting of an outpatient emergency department digital radiography and PACS cannot be realised without problems. We present our first experience with the installation and 10 months filmless routine in the X-ray division for traumatology outpatients at the university of Innsbruck department of radiology. (orig.) [de

  3. Herschel-ATLAS: Dust Temperature and Redshift Distribution of SPIRE and PACS Detected Sources Using Submillimetre Colours

    Science.gov (United States)

    Amblard, A.; Cooray, Asantha; Serra, P.; Temi, P.; Barton, E.; Negrello, M.; Auld, R.; Baes, M.; Baldry, I. K.; Bamford, S.; hide

    2010-01-01

    We present colour-colour diagrams of detected sources in the Herschel-ATLAS Science Demonstration Field from 100 to 500/microns using both PACS and SPIRE. We fit isothermal modified-blackbody spectral energy distribution (SED) models in order to extract the dust temperature of sources with counterparts in GAMA or SDSS with either a spectroscopic or a photometric redshift. For a subsample of 331 sources detected in at least three FIR bands with significance greater than 30 sigma, we find an average dust temperature of (28 plus or minus 8)K. For sources with no known redshifts, we populate the colour-colour diagram with a large number of SEDs generated with a broad range of dust temperatures and emissivity parameters and compare to colours of observed sources to establish the redshift distribution of those samples. For another subsample of 1686 sources with fluxes above 35 mJy at 350 microns and detected at 250 and 500 microns with a significance greater than 3sigma, we find an average redshift of 2.2 plus or minus 0.6.

  4. Treatment of coal gasification wastewater by membrane bioreactor hybrid powdered activated carbon (MBR–PAC) system.

    Science.gov (United States)

    Jia, Shengyong; Han, Hongjun; Hou, Baolin; Zhuang, Haifeng; Fang, Fang; Zhao, Qian

    2014-12-01

    A laboratory-scale membrane bioreactor hybrid powdered activated carbon (MBR–PAC) system was developed to treat coal gasification wastewater to enhance the COD, total phenols (TPh), NH4+ removals and migrate the membrane fouling. Since the MBR–PAC system operated with PAC dosage of 4 g L−1, the maximum removal efficiencies of COD, TPh and NH4+ reached 93%, 99% and 63%, respectively with the corresponding influent concentrations of 2.27 g L−1, 497 mg L−1 and 164 mg N L−1; the PAC extraction efficiencies of COD, TPh and NH4+ were 6%, 3% and 13%, respectively; the transmembrane pressure decreased 34% with PAC after 50 d operation. The results demonstrate that PAC played a key role in the enhancement of biodegradability and mitigation of membrane fouling.

  5. Potential and Limitations of Photometric Reconstruction Through a Flock of Dove Cubesats

    Science.gov (United States)

    Altena, B.; Mousivand, A.; Mascaro, J.; Kääb, A.

    2017-10-01

    When Earth observation satellite systems are designed, one typically prefers a sun-synchronous orbit. However, the first generations of cubesats from Planet were deployed out of the International Space Station (ISS) and therefore do not obey such an orbit. Their configuration samples at different local times within the mid-latitudes. Consequently, it is in theory possible to exploit photometric techniques and extract highly detailed topographic information. In this study we demonstrate and explore photometry based on Planet cubesat images for Tyndall glacier at the Southern Patagonian icefield, and Zhadang glacier situated on the Tibetan plateau.

  6. Photometrical analysis of the Neck-Line structure of Comet Bennet 1970II

    International Nuclear Information System (INIS)

    Fulle, M.; Sedmak, G.

    1988-01-01

    The Kimura and Liu (1977) analysis of the motion in space of cometary dust tail grains, which furnished information on the size-dependence of the dust ejection velocity from the inner coma and the size distribution on a millimetric scale, is presently applied to the Neck-Line Structure (NLS) displayed by Comet Bennett 1970II at the begining of May, 1970. Attention is given to two photographs of the comet which have been analyzed by digital image processing in order to extract reliable photometric data; the strong excess of millimetric grains noted is in agreement with the Fulle (1987) results for preperihelion times. 24 references

  7. PAC and μSr investigations of light interstitial diffusion in intermetallic hydrides

    International Nuclear Information System (INIS)

    Boyer, P.; Baudry, A.

    1988-01-01

    Specific aspects of the Perturbed Angular Correlation (PAC) of gamma rays concerning its application to the study of atomic diffusion in solids are presented. PAC results recently obtained on the 181 Ta probe in several crystalline and amorphous phases of Zr 2 Ni hydrides are briefly summarized. Preliminary μSR results relative to these intermetallic hydrides are presented and compared to the PAC data

  8. Lessons learned from a whole hospital PACS installation. Picture Archiving and Communication System.

    Science.gov (United States)

    Pilling, J R

    2002-09-01

    The Norfolk and Norwich University Hospital has incorporated a fully filmless Picture Archiving and Communication System (PACS) as part of a new hospital provision using PFI funding. The PACS project has been very successful and has met with unanimous acclaim from radiologists and clinicians. A project of this size cannot be achieved without learning some lessons from mistakes and recognising areas where attention to detail resulted in a successful implementation. This paper considers the successes and problems encountered in a large PACS installation.

  9. How can the impact of PACS on inpatient length of hospital stay be established?

    Science.gov (United States)

    Bryan, Stirling; Muris, Nicole; Keen, Justin; Weatherburn, Gwyneth C.; Buxton, Martin J.

    1994-05-01

    Many have argued that the introduction of a large-scale PACS system into a hospital will bring about reductions in the length of inpatient hospital stays. There is currently no convicting empirical evidence to support such claims. As part of the independent evaluation exercise being undertaken alongside the Hammersmith Hospital PACS implementation, an assessment is being made of the impact of PACS on length of stay for selected patient groups. This paper reports the general research methods being employed to undertake this assessment and provides some baseline results from the analysis of total hip replacement patients and total knee replacement patients treated prior to the introduction of PACS.

  10. Learning Photometric Invariance for Object Detection

    NARCIS (Netherlands)

    Álvarez, J.M.; Gevers, T.; López, A.M.

    2010-01-01

    Color is a powerful visual cue in many computer vision applications such as image segmentation and object recognition. However, most of the existing color models depend on the imaging conditions that negatively affect the performance of the task at hand. Often, a reflection model (e.g., Lambertian

  11. Improving color constancy by photometric edge weighting

    NARCIS (Netherlands)

    Gijsenij, A.; Gevers, T.; van de Weijer, J.

    2012-01-01

    Edge-based color constancy methods make use of image derivatives to estimate the illuminant. However, different edge types exist in real-world images, such as material, shadow, and highlight edges. These different edge types may have a distinctive influence on the performance of the illuminant

  12. Long photometric cycles in hot algols

    Directory of Open Access Journals (Sweden)

    Mennickent R.E.

    2017-01-01

    Full Text Available We summarize the development of the field of Double Periodic Variables (DPVs, Mennickent et al. 2003 during the last fourteen years, placing these objects in the context of intermediate-mass close interacting binaries similar to β Persei (Algol and β Lyrae (Sheliak which are generally called Algols. DPVs show enigmatic long photometric cycles lasting on average about 33 times the orbital period, and have physical properties resembling, in some aspects, β Lyrae. About 200 of these objects have been found in the Galaxy and the Magellanic Clouds. Light curve models and orbitally resolved spectroscopy indicate that DPVs are semi-detached interacting binaries consisting of a near main-sequence B-type star accreting matter from a cooler giant and surrounded by an optically thick disc. This disc contributes a significant fraction of the system luminosity and its luminosity is larger than expected from the phenomenon of mass accretion alone. In some systems, an optically thin disc component is observed in well developed Balmer emission lines. The optically thick disc shows bright zones up to tens percent hotter than the disc, probably indicating shocks resulting from the gas and disc stream dynamics. We conjecture that a hotspot wind might be one of the channels for a mild systemic mass loss, since evidence for jets, winds or general mass loss has been found in β Lyrae, AUMon, HD170582, OGLE05155332-6925581 and V393 Sco. Also, theoretical work by Van Rensbergen et al. (2008 and Deschamps et al. (2013 suggests that hotspot could drive mass loss from Algols. We give special consideration to the recently published hypothesis for the long-cycle, consisting of variable mass transfer driven by a magnetic dynamo (Schleicher and Mennickent 2017. The Applegate (1992 mechanism should modify cyclically the equatorial radius of the chromospherically active donor producing cycles of enhanced mass loss through the inner Lagrangian point. Chromospheric emission in

  13. Optical Photometric Observations of GEO Debris

    Science.gov (United States)

    Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Edwin S.; Abercromby, Kira J.; Kelecy, Thomas M.; Horstman, Matt

    2010-01-01

    We report on a continuing program of optical photometric measurements of faint orbital debris at geosynchronous Earth orbit (GEO). These observations can be compared with laboratory studies of actual spacecraft materials in an effort to determine what the faint debris at GEO may be. We have optical observations from Cerro Tololo Inter-American Observatory (CTIO) in Chile of two samples of debris: 1. GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Curtis-Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 t11 magnitude that are discovered in the MODEST survey. 2. A smaller sample of high area to mass ratio (AMR) objects discovered independently, and acquired using predictions from orbits derived from independent tracking data collected days prior to the observations. Our optical observations in standard astronomical BVRI filters are done with either telescope, and with the telescope tracking the debris object at the object's angular rate. Observations in different filters are obtained sequentially. We have obtained 71 calibrated sequences of R-B-V-I-R magnitudes. A total of 66 of these sequences have 3 or more good measurements in all filters (not contaminated by star streaks or in Earth's shadow). Most of these sequences show brightness variations, but a small subset has observed brightness variations consistent with that expected from observational errors alone. The majority of these stable objects are redder than a solar color in both B-R and R-I. There is no dependence on color with brightness. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and

  14. Photometric Studies of Orbital Debris at GEO

    Science.gov (United States)

    Seitzer, Patrick; Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Hortsman, Matt

    2009-01-01

    Orbital debris represents a significant and increasing risk to operational spacecraft. Here we report on photometric observations made in standard BVRI filters at the Cerro Tololo Inter-American Observatory (CTIO) in an effort to determine the physical characteristics of optically faint debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan s 0.6-m Curtis-Schmidt telescope (known as MODEST, for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. For a sample of 50 objects, calibrated sequences in RB- V-I-R filters have been obtained with the CTIO/SMARTS 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could imply that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For irregularly shaped objects tumbling at unknown orientations and rates, such sequential filter measurements using one telescope are subject to large errors for interpretation. If all observations in all filters in a particular sequence are of the same surface at the same solar and viewing angles, then the colors are meaningful. Where this is not the case, interpretation of the observed colors is impossible. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO/SMARTS 0.9-m observes in B, and the Schmidt in R. The CCD cameras are electronically linked together so that the start time and duration of observations are both the same to better than 50 milliseconds. Now the observed B-R color is a true measure of the scattered illuminated area of the debris piece for that observation.

  15. Photometric Studies of GEO Orbital Debris

    Science.gov (United States)

    Seitzer, Patrick; Rodriquez-Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Horstman, Matt

    2009-01-01

    The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the Cerro Tololo Inter- American Observatory (CTIO) 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R=15th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? More than 90 calibrated sequences of R-B-V-I-R magnitudes for a sample of 50 objects have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the

  16. Photometric redshifts of galaxies from SDSS and 2MASS

    International Nuclear Information System (INIS)

    Wang Tao; Gu Qiusheng; Huang Jiasheng

    2009-01-01

    In order to find the physical parameters which determine the accuracy of photometric redshifts, we compare the spectroscopic and photometric redshifts (photo-z's) for a large sample of ∼ 80000 SDSS-2MASS galaxies. Photo-z's in this paper are estimated by using the artificial neural network photometric redshift method (ANNz). For a subset of ∼40000 randomly selected galaxies, we find that the photometric redshift recovers the spectroscopic redshift distribution very well with rms of 0.016. Our main results are as follows: (1) Using magnitudes directly as input parameters produces more accurate photo-z's than using colors; (2) The inclusion of 2MASS (J, H, K s ) bands does not improve photo-z's significantly, which indicates that near infrared data might not be important for the low-redshift sample; (3) Adding the concentration index (essentially the steepness of the galaxy brightness profile) as an extra input can improve the photo-z's estimation up to ∼ 10 percent; (4) Dividing the sample into early- and late-type galaxies by using the concentration index, normal and abnormal galaxies by using the emission line flux ratios, and red and blue galaxies by using color index (g - r), we can improve the accuracy of photo-z's significantly; (5) Our analysis shows that the outliers (where there is a big difference between the spectroscopic and photometric redshifts) are mainly correlated with galaxy types, e.g., most outliers are late-type (blue) galaxies.

  17. Digital medical imaging

    International Nuclear Information System (INIS)

    Goeringer, F.; Mun, S.K.; Kerlin, B.D.

    1989-01-01

    In formulating an implementation strategy for digital medical imaging, three interrelated thrusts have emerged for the defense medical establishment. These thrusts: totally filmless medical imaging on the battlefield, teleradiology, and DIN/PACS for peacetime military health care are discussed. They have implications in their fully developed form as resource savers and quality improvers for the unique aspects of military health care

  18. The Photometric lightcurve of Comet 1P/Halley

    Science.gov (United States)

    Bair, Allison N.; Schleicher, David G.

    2014-11-01

    Comet 1P/Halley is considered an important object for a number of reasons. Not only is it the first-identified and brightest periodic comet, being the only periodic comet visible to the naked eye at every apparition, but in 1986 Halley became the first comet to be imaged by fly-by spacecraft. The NASA-funded International Halley Watch (IHW) directly supported the spacecraft by providing narrowband filters for groundbased photometric observations, and until the arrival of Hale-Bopp (1995 O1), Halley was the subject of the largest groundbased observational campaign in history. Following considerable controversy regarding its rotation period, it was eventually determined to be in complex rotation -- the first comet to be so identified. While the overall brightness variations of the coma repeated with a period of about 7.4 days, the detailed period and shape of the lightcurve constantly evolved. The determination of the specific characteristics of each of the two components of its non-principal axis rotational state has remained elusive.To resolve this situation we have now incorporated all of the narrowband photometry, taken by 21 telescopes from around the world and submitted to the IHW archive, to create the most complete homogeneous lightcurve possible. Using measurements of three gas species and the dust, the lightcurve was investigated and found to alternate between a double- and triple-peaked shape, with no single feature being present throughout the entire duration of our dataset (316 days). The apparent period as a function of time was extracted and seen to vary in a step-wise manner between 7.27 and 7.60 days. Taken together, these results were used to produce a synthetic lightcurve revealing Halley's behavior even when no data were available. Details of this and other results, to be used to constrain future detailed modeling, will be presented. This research is supported by NASA's Planetary Atmospheres Program.

  19. Mars Exploration Rover Pancam Photometric Data QUBs: Definition and Example Uses.

    Science.gov (United States)

    Soderblom, J. M.; Bell, J. F.; Arvidson, R. E.; Johnson, J. R.; Johnson, M. J.; Seelos, F. P.

    2004-12-01

    Pancam multi-spectral observations acquired at the Mars Exploration Rover Spirit and Opportunity landing sites are being assembled into a multi-layer format know as a QUB. For any given pixel in a Pancam image the QUB will contain values for the radiance factor, incidence (i), emission (e), and phase (g) angles, X, Y, and Z distance in a rover-based coordinate system, disparity in number of pixels between the left and right eye images and range data. Good range data is required for the generation of a Pancam QUB. The radiance factor (I/F, where I is the measured scene radiance on sensor and π F is the incident solar irradiance) is calculated using a combination of preflight calibration data and information obtained from near-simultaneous observations of an onboard reflectance calibration target. The range, X, Y, Z and disparity data, and i, e, and g are calculated using routines developed by JPL's MIPL and Cornell. When possible, these data have been interpolated to maximize parameter coverage; a map of non-interpolated data is also included in each QUB. QUBs should prove very useful in photometric studies (e.g., Johnson et al.; Seelos, et al., this conference), detailed spectral analyses (e.g., Bell et al., this conference), and detailed topographic/DTM studies. Here we present two examples of the utilization of the information contained in Pancam QUBs. In one example we remove the photometric variability from spectra collected from multiple facets of a rock using knowledge of i, e, g and derived photometric functions. This is necessary if one wishes to conduct comparative studies of observations acquired under varying geometries and lighting conditions. In another example we present an analysis using the discrete ordinate multiple scattering radiative transfer code DISORT where we separate the atmosphere and surface contributions of the surface reflectance.

  20. Diffusion-weighted MRI of the prostate at 3.0 T: comparison of endorectal coil (ERC) MRI and phased-array coil (PAC) MRI-The impact of SNR on ADC measurement.

    Science.gov (United States)

    Mazaheri, Yousef; Vargas, H Alberto; Nyman, Gregory; Shukla-Dave, Amita; Akin, Oguz; Hricak, Hedvig

    2013-10-01

    To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC+PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3.0 T. The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Twenty-five patients with biopsy-proven prostate cancer underwent standard 3-T MRI using 2 different coil arrangements (ERC+PAC and PAC only) in the same session. DW-MRI at five b-values (0, 600, 1000, 1200, and 1500 s/mm(2)) were acquired using both coil arrangements. On b=0 images, signal-to-noise ratios (SNRs) were measured as the ratio of the mean signal from PZ and TZ ROIs to the standard deviation from the mean signal in an artifact-free ROI in the rectum. Matching regions-of-interest (ROIs) were identified in the peripheral zone and transition zone on ERC-MRI and PAC-MRI. For each ROI, mean ADC values for all zero and non-zero b-value combinations were computed. Mean SNR with ERC-MRI at PZ (66.33 ± 27.07) and TZ (32.69 ± 12.52) was 9.27 and 5.52 times higher than with PAC-MRI ((7.32 ± 2.30) and (6.13 ± 1.56), respectively) (PERC-MRI (PERC. To address these requirements, clinical MR systems should have image processing capabilities which incorporate the noise distribution. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Pac-Rim LNG project : final project report specifications

    International Nuclear Information System (INIS)

    1996-01-01

    PAC-RIM LNG Inc. has submitted a proposal to the British Columbia Environmental Assessment Office, to develop a liquefied natural gas project which would purchase pipeline quality natural gas from sources in northeast British Columbia and Alberta and transport it via a dedicated pipeline system to a LNG processing plant on tidewater on the Pacific coast. The project would include storage and processing facilities and a marine loading terminal. This document sets out the final project report specifications prepared by the Project Committee on the basis of input received from the public, First Nations and federal, provincial and local governments

  2. PACS/information systems interoperability using Enterprise Communication Framework.

    Science.gov (United States)

    alSafadi, Y; Lord, W P; Mankovich, N J

    1998-06-01

    Interoperability among healthcare applications goes beyond connectivity to allow components to exchange structured information and work together in a predictable, coordinated fashion. To facilitate building an interoperability infrastructure, an Enterprise Communication Framework (ECF) was developed by the members of the Andover Working Group for Healthcare Interoperability (AWG-OHI). The ECF consists of four models: 1) Use Case Model, 2) Domain Information Model (DIM), 3) Interaction Model, and 4) Message Model. To realize this framework, a software component called the Enterprise Communicator (EC) is used. In this paper, we will demonstrate the use of the framework in interoperating a picture archiving and communication system (PACS) with a radiology information system (RIS).

  3. Ceramic sphere-pac breeder design for fusion blankets

    International Nuclear Information System (INIS)

    Gierszewski, P.J.; Sullivan, J.D.

    1991-01-01

    Randomly packed beds of ceramic spheres are a practical approach to surrounding fusion plasmas with tritium-breeding material. This paper examines the general properties of sphere-pac beds for application in fusion breeder blankets. The design considerations and models are reviewed for packing, tritium breeding and recovery, thermal conductivity, purge-gas pressure drop, mechanical behavior and fabrication. The design correlations are compared against available fusion ceramic data. Specific conclusions are that ternary (three-size) beds are not attractive for fusion blankets, and that the fusion spheres should be as large as possible subject primarily to packing constraints. (orig.)

  4. Impurity cluster interaction in fcc metals studied by PAC

    International Nuclear Information System (INIS)

    Deicher, M.; Echt, O.; Recknagel, E.; Wichert, T.

    1981-01-01

    A defect configuration of high thermal stability has been observed by PAC in Au, showing the same properties as previously published configuration in Cu and Ni. We prove that these configurations cannot consist of any small defect complex with well-defined size; especially the observed influence of the damaging conditions on the thermal stability of the defects in Au and Cu would contradict such an assumption. It is shown that probe atoms trapped at large clusters of variable size can nevertheless experience a unique electric field gradient, and that in our case intrinsic stacking faults, formed by vacancies, can account for all the measured properties. (orig.)

  5. Diffusion-weighted MRI of the prostate at 3.0 T: Comparison of endorectal coil (ERC) MRI and phased-array coil (PAC) MRI—The impact of SNR on ADC measurement

    International Nuclear Information System (INIS)

    Mazaheri, Yousef; Vargas, H. Alberto; Nyman, Gregory; Shukla-Dave, Amita; Akin, Oguz; Hricak, Hedvig

    2013-01-01

    Purpose: To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC + PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3.0 T. Methods: The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Twenty-five patients with biopsy-proven prostate cancer underwent standard 3-T MRI using 2 different coil arrangements (ERC + PAC and PAC only) in the same session. DW-MRI at five b-values (0, 600, 1000, 1200, and 1500 s/mm 2 ) were acquired using both coil arrangements. On b = 0 images, signal-to-noise ratios (SNRs) were measured as the ratio of the mean signal from PZ and TZ ROIs to the standard deviation from the mean signal in an artifact-free ROI in the rectum. Matching regions-of-interest (ROIs) were identified in the peripheral zone and transition zone on ERC-MRI and PAC-MRI. For each ROI, mean ADC values for all zero and non-zero b-value combinations were computed. Results: Mean SNR with ERC-MRI at PZ (66.33 ± 27.07) and TZ (32.69 ± 12.52) was 9.27 and 5.52 times higher than with PAC-MRI ((7.32 ± 2.30) and (6.13 ± 1.56), respectively) (P < 0.0001 for both). ADCs from DW-MR images obtained with all b-values in the PZ and TZ were significantly lower with PAC-MRI than with ERC-MRI (P < 0.001 for all). Conclusion: Lower SNR of DW-MR images of the prostate obtained with a PAC can significantly decrease ADC values at higher b-values compared to similar measurements obtained using the ERC. To address these requirements, clinical MR systems should have image processing capabilities which incorporate the noise distribution

  6. Cosmological forecasts from photometric measurements of the angular correlation function

    International Nuclear Information System (INIS)

    Sobreira, F.; Rosenfeld, R.; Simoni, F. de; Costa, L. A. N. da; Maia, M. A. G.; Makler, M.

    2011-01-01

    We study forecasts for the accuracy of the determination of cosmological parameters from future large-scale photometric surveys obtained using the full shape of the 2-point galaxy angular correlation function. The effects of linear redshift-space distortion, photometric redshift Gaussian errors, galaxy bias and nonlinearities in the power spectrum are included on our analysis. The Fisher information matrix is constructed with the full covariance matrix, including the correlation between nearby redshift shells arising from the photometric redshift error. We show that under some reasonable assumptions, a survey such as the imminent Dark Energy Survey should be able to constrain the dark energy equation of state parameter w and the cold dark matter density Ω cdm with a precision of the order of 20% and 13%, respectively, from the full shape of the angular correlation function alone. When combined with priors from other observations the precision in the determination of these parameters improve to 8% and 4%, respectively.

  7. Planck 2013 results. VIII. HFI photometric calibration and mapmaking

    CERN Document Server

    Ade, P A R; Armitage-Caplan, C; Arnaud, M; Ashdown, M; Atrio-Barandela, F; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bertincourt, B; Bielewicz, P; Bobin, J; Bock, J J; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bridges, M; Bucher, M; Burigana, C; Cardoso, J -F; Catalano, A; Challinor, A; Chamballu, A; Chary, R -R; Chen, X; Chiang, L -Y; Chiang, H C; Christensen, P R; Church, S; Clements, D L; Colombi, S; Colombo, L P L; Combet, C; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Delouis, J -M; Désert, F -X; Dickinson, C; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dupac, X; Efstathiou, G; Enßlin, T A; Eriksen, H K; Filliard, C; Finelli, F; Forni, O; Frailis, M; Franceschi, E; Galeotta, S; Ganga, K; Giard, M; Giardino, G; Giraud-Héraud, Y; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Hansen, F K; Hanson, D; Harrison, D; Helou, G; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Hobson, M; Holmes, W A; Hornstrup, A; Hovest, W; Huffenberger, K M; Jaffe, T R; Jaffe, A H; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Knox, L; Kunz, M; Kurki-Suonio, H; Lagache, G; Lamarre, J -M; Lasenby, A; Laureijs, R J; Lawrence, C R; Jeune, M Le; Lellouch, E; Leonardi, R; Leroy, C; Lesgourgues, J; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maffei, B; Mandolesi, N; Maris, M; Marshall, D J; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Matthai, F; Maurin, L; Mazzotta, P; McGehee, P; Meinhold, P R; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Moreno, R; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Osborne, S; Oxborrow, C A; Paci, F; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Partridge, B; Pasian, F; Patanchon, G; Perdereau, O; Perotto, L; Perrotta, F; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Popa, L; Poutanen, T; Pratt, G W; Prézeau, G; Prunet, S; Puget, J -L; Rachen, J P; Reinecke, M; Remazeilles, M; Renault, C; Ricciardi, S; Riller, T; Ristorcelli, I; Rocha, G; Rosset, C; Roudier, G; Rusholme, B; Santos, D; Savini, G; Shellard, E P S; Spencer, L D; Starck, J -L; Stolyarov, V; Stompor, R; Sudiwala, R; Sunyaev, R; Sureau, F; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Tavagnacco, D; Techene, S; Terenzi, L; Tomasi, M; Tristram, M; Tucci, M; Umana, G; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Vittorio, N; Wade, L A; Wandelt, B D; Yvon, D; Zacchei, A; Zonca, A

    2014-01-01

    This paper describes the processing applied to the HFI cleaned time-ordered data to produce photometrically calibrated maps. HFI observes the sky over a broad range of frequencies, from 100 to 857 GHz. To get the best accuracy on the calibration on such a large range, two different photometric calibration schemes have to be used. The 545 and 857 \\GHz\\ data are calibrated using Uranus and Neptune flux density measurements, compared with models of their atmospheric emissions to calibrate the data. The lower frequencies (below 353 GHz) are calibrated using the cosmological microwave background dipole.One of the components of this anisotropy results from the orbital motion of the satellite in the Solar System, and is therefore time-variable. Photometric calibration is thus tightly linked to mapmaking, which also addresses low frequency noise removal. The 2013 released HFI data show some evidence for apparent gain variations of the HFI bolometers' detection chain. These variations were identified by comparing obse...

  8. Morphological and photometric studies of galaxies by electronography

    International Nuclear Information System (INIS)

    Youll, D.P.

    1978-10-01

    Astronomical sources of low surface brightness, or sources with high luminosity gradients can be difficult to observe with photographic techniques. However, developments in electronographic techniques over recent years have made them suitable for precise observations of such objects. The use of these techniques for morphological and photometric studies of galaxies is discussed. Where appropriate, improvements in the methods for recovering information from electronographs, and analysing the data with computers are suggested. These techniques were used to study eight galaxy systems which have compact parts where the luminosity gradients are relatively high. Morphological studies of these systems are presented, together with measurements of some of their photometric parameters. The galaxy NGC 4881 was also studied so that the photometric calibration could be checked against previous studies, and so that the parameters of compact galaxies could be compared against this elliptical galaxy. (author)

  9. Photometric Analysis in the Kepler Science Operations Center Pipeline

    Science.gov (United States)

    Twicken, Joseph D.; Clarke, Bruce D.; Bryson, Stephen T.; Tenenbaum, Peter; Wu, Hayley; Jenkins, Jon M.; Girouard, Forrest; Klaus, Todd C.

    2010-01-01

    We describe the Photometric Analysis (PA) software component and its context in the Kepler Science Operations Center (SOC) pipeline. The primary tasks of this module are to compute the photometric flux and photocenters (centroids) for over 160,000 long cadence (thirty minute) and 512 short cadence (one minute) stellar targets from the calibrated pixels in their respective apertures. We discuss the science algorithms for long and short cadence PA: cosmic ray cleaning; background estimation and removal; aperture photometry; and flux-weighted centroiding. We discuss the end-to-end propagation of uncertainties for the science algorithms. Finally, we present examples of photometric apertures, raw flux light curves, and centroid time series from Kepler flight data. PA light curves, centroid time series, and barycentric timestamp corrections are exported to the Multi-mission Archive at Space Telescope [Science Institute] (MAST) and are made available to the general public in accordance with the NASA/Kepler data release policy.

  10. Photometric behavior of SS 433 in 1979 and 1980

    International Nuclear Information System (INIS)

    Mazeh, T.; Tel Aviv University; Wise Observatory, Tel Aviv, Israel); Leibowitz, E.M.; Wise Observatory, Tel Aviv, Israel)

    1981-01-01

    Results and analysis of photometric measurements performed in the last two observing seasons of SS 433 are presented. The light of the star in the V and the B photometric bands varies with a period of either 6.55 or 6.43 days. The periodicity of approximately 164 days is also apparent in the photometric data, with its first and third harmonics. Fluctuations of the order of a half a magnitude within a few hours have also been recorded. The B-V color shows no dependence on the phase of the periodic variations, while it does change by up to 0.25 mag, in an apparent association with the short time scale fluctuations

  11. METAPHOR: Probability density estimation for machine learning based photometric redshifts

    Science.gov (United States)

    Amaro, V.; Cavuoti, S.; Brescia, M.; Vellucci, C.; Tortora, C.; Longo, G.

    2017-06-01

    We present METAPHOR (Machine-learning Estimation Tool for Accurate PHOtometric Redshifts), a method able to provide a reliable PDF for photometric galaxy redshifts estimated through empirical techniques. METAPHOR is a modular workflow, mainly based on the MLPQNA neural network as internal engine to derive photometric galaxy redshifts, but giving the possibility to easily replace MLPQNA with any other method to predict photo-z's and their PDF. We present here the results about a validation test of the workflow on the galaxies from SDSS-DR9, showing also the universality of the method by replacing MLPQNA with KNN and Random Forest models. The validation test include also a comparison with the PDF's derived from a traditional SED template fitting method (Le Phare).

  12. First results of astrometric and photometric processing of scanned plates DLFA MAO NAS of Ukraine

    Science.gov (United States)

    Shatokhina, S.; Andruk, V.; Yatsenko, A.

    2011-02-01

    In the paper the first estimation of astrometric and photometric results of digitization of images on plates of Double Long Focus Astrograph (DLFA) was made. The digitization of plates was carried out with the scanner Microtek ScanMaker 9800XL TMA. For image processing the package LINUX/MIDAS/ROMAFOT was used. For selected plates DLFA mean square errors for equatorial coordinates (in a system of TYCHO-2 catalogue) and stellar magnitudes (in the Johnson B-system) per one image are 0.06" and 0.13m. The errors are of random nature and there are no systematic dependences on coordinates, magnitudes and colour of stars. The comparison of obtained results with that of earlier plate measurements obtained with complex PARSEC was made.

  13. "TNOs are Cool": A survey of the trans-Neptunian region. XII. Thermal light curves of Haumea, 2003 VS2 and 2003 AZ84 with Herschel/PACS

    Science.gov (United States)

    Santos-Sanz, P.; Lellouch, E.; Groussin, O.; Lacerda, P.; Müller, T. G.; Ortiz, J. L.; Kiss, C.; Vilenius, E.; Stansberry, J.; Duffard, R.; Fornasier, S.; Jorda, L.; Thirouin, A.

    2017-08-01

    Context. Time series observations of the dwarf planet Haumea and the Plutinos 2003 VS2 and 2003 AZ84 with Herschel/PACS are presented in this work. Thermal emission of these trans-Neptunian objects (TNOs) were acquired as part of the "TNOs are Cool" Herschel Space Observatory key programme. Aims: We search for the thermal light curves at 100 and 160 μm of Haumea and 2003 AZ84, and at 70 and 160 μm for 2003 VS2 by means of photometric analysis of the PACS data. The goal of this work is to use these thermal light curves to obtain physical and thermophysical properties of these icy Solar System bodies. Methods: When a thermal light curve is detected, it is possible to derive or constrain the object thermal inertia, phase integral and/or surface roughness with thermophysical modeling. Results: Haumea's thermal light curve is clearly detected at 100 and 160 μm. The effect of the reported dark spot is apparent at 100 μm. Different thermophysical models were applied to these light curves, varying the thermophysical properties of the surface within and outside the spot. Although no model gives a perfect fit to the thermal observations, results imply an extremely low thermal inertia (0.73) for Haumea's surface. We note that the dark spot region appears to be only weakly different from the rest of the object, with modest changes in thermal inertia and/or phase integral. The thermal light curve of 2003 VS2 is not firmly detected at 70 μm and at 160 μm but a thermal inertia of (2 ± 0.5) MKS can be derived from these data. The thermal light curve of 2003 AZ84 is not firmly detected at 100 μm. We apply a thermophysical model to the mean thermal fluxes and to all the Herschel/PACS and Spitzer/MIPS thermal data of 2003 AZ84, obtaining a close to pole-on orientation as the most likely for this TNO. Conclusions: For the three TNOs, the thermal inertias derived from light curve analyses or from the thermophysical analysis of the mean thermal fluxes confirm the generally small

  14. Impact of a PACS/RIS-integrated speech recognition system on radiology reporting time and report availability

    International Nuclear Information System (INIS)

    Trumm, C.G.; Glaser, C.; Paasche, V.; Kuettner, B.; Francke, M.; Nissen-Meyer, S.; Reiser, M.; Crispin, A.; Popp, P.

    2006-01-01

    Purpose: Quantification of the impact of a PACS/RIS-integrated speech recognition system (SRS) on the time expenditure for radiology reporting and on hospital-wide report availability (RA) in a university institution. Material and Methods: In a prospective pilot study, the following parameters were assessed for 669 radiographic examinations (CR): 1. time requirement per report dictation (TED: dictation time (s)/number of images [examination] x number of words [report]) with either a combination of PACS/tape-based dictation (TD: analog dictation device/minicassette/transcription) or PACS/RIS/speech recognition system (RR: remote recognition/transcription and OR: online recognition/self-correction by radiologist), respectively, and 2. the Report Turnaround Time (RTT) as the time interval from the entry of the first image into the PACS to the available RIS/HIS report. Two equal time periods were chosen retrospectively from the RIS database: 11/2002-2/2003 (only TD) and 11/2003-2/2004 (only RR or OR with speech recognition system [SRS]). The midterm (≥24 h, 24 h intervals) and short-term (< 24 h, 1 h intervals), RA after examination completion were calculated for all modalities and for Cr, CT, MR and XA/DS separately. The relative increase in the mid-term RA (RIMRA: related to total number of examinations in each time period) and increase in the short-term RA (ISRA: ratio of available reports during the 1st to 24th hour) were calculated. Results: Prospectively, there was a significant difference between TD/RR/OR (n=151/257/261) regarding mean TED (0.44/0.54/0.62 s [per word and image]) and mean RTT (10.47/6.65/1.27 h), respectively. Retrospectively, 37 898/39 680 reports were computed from the RIS database for the time periods of 11/2002-2/2003 and 11/2003-2/2004. For CR/CT there was a shift of the short-term RA to the first 6 hours after examination completion (mean cumulative RA 20% higher) with a more than three-fold increase in the total number of available

  15. CALIBRATING PHOTOMETRIC REDSHIFT DISTRIBUTIONS WITH CROSS-CORRELATIONS

    International Nuclear Information System (INIS)

    Schulz, A. E.

    2010-01-01

    The next generation of proposed galaxy surveys will increase the number of galaxies with photometric redshift identifications by two orders of magnitude, drastically expanding both the redshift range and detection threshold from the current state of the art. Obtaining spectra for a fair subsample of these new data could be cumbersome and expensive. However, adequate calibration of the true redshift distribution of galaxies is vital to tapping the potential of these surveys to illuminate the processes of galaxy evolution and to constrain the underlying cosmology and growth of structure. We examine here an alternative to direct spectroscopic follow-up: calibration of the redshift distribution of photometric galaxies via cross-correlation with an overlapping spectroscopic survey whose members trace the same density field. We review the theory, develop a pipeline to implement the method, apply it to mock data from N-body simulations, and examine the properties of this redshift distribution estimator. We demonstrate that the method is generally effective, but the estimator is weakened by two main factors. One is that the correlation function of the spectroscopic sample must be measured in many bins along the line of sight, which renders the measurement noisy and interferes with high-quality reconstruction of the photometric redshift distribution. Also, the method is not able to disentangle the photometric redshift distribution from redshift dependence in the bias of the photometric sample. We establish the impact of these factors using our mock catalogs. We conclude that it may still be necessary to spectroscopically follow up a fair subsample of the photometric survey data. Nonetheless, it is significant that the method has been successfully implemented on mock data, and with further refinement it may appreciably decrease the number of spectra that will be needed to calibrate future surveys.

  16. Photometric Redshifts with the LSST: Evaluating Survey Observing Strategies

    Science.gov (United States)

    Graham, Melissa L.; Connolly, Andrew J.; Ivezić, Željko; Schmidt, Samuel J.; Jones, R. Lynne; Jurić, Mario; Daniel, Scott F.; Yoachim, Peter

    2018-01-01

    In this paper we present and characterize a nearest-neighbors color-matching photometric redshift estimator that features a direct relationship between the precision and accuracy of the input magnitudes and the output photometric redshifts. This aspect makes our estimator an ideal tool for evaluating the impact of changes to LSST survey parameters that affect the measurement errors of the photometry, which is the main motivation of our work (i.e., it is not intended to provide the “best” photometric redshifts for LSST data). We show how the photometric redshifts will improve with time over the 10 year LSST survey and confirm that the nominal distribution of visits per filter provides the most accurate photo-z results. The LSST survey strategy naturally produces observations over a range of airmass, which offers the opportunity of using an SED- and z-dependent atmospheric affect on the observed photometry as a color-independent redshift indicator. We show that measuring this airmass effect and including it as a prior has the potential to improve the photometric redshifts and can ameliorate extreme outliers, but that it will only be adequately measured for the brightest galaxies, which limits its overall impact on LSST photometric redshifts. We furthermore demonstrate how this airmass effect can induce a bias in the photo-z results, and caution against survey strategies that prioritize high-airmass observations for the purpose of improving this prior. Ultimately, we intend for this work to serve as a guide for the expectations and preparations of the LSST science community with regard to the minimum quality of photo-z as the survey progresses.

  17. Talking PACS: Part 2 - why should we change to PACS? | Schulze ...

    African Journals Online (AJOL)

    This article is a critical evaluation of the workflow within a film- and paper-based imaging department. It also illustrates how all the factors culminate to produce poor patient care and decreased productivity. Practical examples are provided within the Tygerberg Hospital scenario. The effect of international trends on the ...

  18. Photometric measurements of solar irradiance variations due to sunspots

    International Nuclear Information System (INIS)

    Chapman, G.A.; Herzog, A.D.; Laico, D.E.; Lawrence, J.K.; Templer, M.S.

    1989-01-01

    A photometric telescope constructed to obtain photometric sunspot areas and deficits on a daily basis is described. Data from this Cartesian full disk telescope (CFDT) are analyzed with attention given to the period between June 4 and June 17, 1985 because of the availability of overlapping sunspot area and irradiance deficit data from high-resolution digital spectroheliograms made with the San Fernando Observatory 28 cm vacuum solar telescope and spectroheliograph. The CFDT sunspot deficits suggest a substantial irradiance contribution from faculae and active region plage. 23 refs

  19. Photometric investigation of the magnetic star 53 Camelopardalis

    International Nuclear Information System (INIS)

    Muciek, M.; Gertner, J.; North, P.; Rufener, F.

    1985-01-01

    New photometric results obtained in the Geneva system are presented for the star 53 Cam. Earlier photometric results obtained in another system are used as well to show the existence of about four ''null-wavelength regions'' between 3400 and 7700 A and to draw the pseudocontinuum of this star. Assuming axisymmetry about the magnetic axis, a simple model of brightness and equivalent width distribution on the surface of the star are proposed. The distribution of the intensity of the γ 5200 depression is given and a slight inhomogeneity of the distribution of effective temperature is suggested. 28 refs., 7 figs., 4 tabs. (author)

  20. [Determination of aluminium in flour foods with photometric method].

    Science.gov (United States)

    Ma, Lan; Zhao, Xin; Zhou, Shuang; Yang, Dajin

    2012-05-01

    To establish a determination method for aluminium in flour foods with photometric method. After samples being treated with microwave digestion and wet digestion, aluminium in staple flour foods was determined by photometric method. There was a good linearity of the result in the range of 0.25 - 5.0 microg/ml aluminium, r = 0.9998; limit of detection (LOD) : 2.3 ng/ml; limit of quantitation (LOQ) : 7 ng/ml. This method of determining aluminium in flour foods is simple, rapid and reliable.

  1. Kinematics and age of 15 stars-photometric solar analogs

    Science.gov (United States)

    Galeev, A. I.; Shimansky, V. V.

    2008-03-01

    The radial and space velocities are inferred for 15 stars that are photometric analogs of the Sun. The space velocity components (U, V, W) of most of these stars lie within the 10-60 km/s interval. The star HD 225239, which in our previous papers we classified as a subgiant, has a space velocity exceeding 100 km/s, and belongs to the thick disk. The inferred fundamental parameters of the atmospheres of solar analogs are combined with published evolutionary tracks to estimate the masses and ages of the stars studied. The kinematics of photometric analogs is compared to the data for a large group of solar-type stars.

  2. Image Transmission Studies

    Science.gov (United States)

    Blaine, G. James; Hill, Rexford L.; Rueter, Allen P.; Senol, Evren; Studt, James W.

    1988-06-01

    Radiological PACS image sizes and desired retrieval response times demand high-bandwidth communication networks. Local area network technology at speeds higher that 10 Megabits/second (IEEE 802.3) have not achieved standardization nor production volume. Our current PACS experiments are based on a three-level subnet approach using 10 Mb/s Ethernet channels. An Ethernet channel is shown to support image transfers at an average throughput of 3 Mb/s. Preliminary measurements and simulation results suggest that traffic from as many as two-to-three archives can be supported on the same channel.

  3. Image transmission studies

    International Nuclear Information System (INIS)

    Blaine, G.J.; Hill, R.L.; Rueter, A.P.; Senol, E.; Studt, J.W.

    1988-01-01

    This paper discusses radiological PACS image sizes and desired retrieval response time that demand high-bandwidth communication networks. Local area network technology at speeds higher that 10 Megabits/second (IEEE 802.3) have not achieved standardization nor production volume. The authors describe current PACS experiments based on a three-level subnet approach using 10 Mb/s Ethernet channels. An Ethernet channel is shown to support image transfers at an average throughput of 3 Mb/s. Preliminary measurements and simulation results suggest that traffic from as many as two-to-three archives can be supported on the same channel

  4. KIS-RIS-PACS integration: the Marburg approach

    International Nuclear Information System (INIS)

    Klose, K.J.; Schaefer, C.; Kail, S.; Roethke, M.; Zhang, L.

    2005-01-01

    When describing the development of data processing at the Department of Radiology at the Philipps University of Marburg, three phases can be identified covering the areas of patient care, education, and research as well as administrative and organizational aspects. The first phase (1987-1995) was centered on radiology and characterized by the early implementation of the radiology information system (RIS) and installation of a picture archiving and communication system (PACS). The experiences gained during this phase led to intensive discussion on application-oriented information processing. The second phase (1996-2000) describes the changes in the general framework brought by Internet technology and international standards. The course was set for the future of data processing in the hospital setting. The phase ended with implementation of a clinical workplace system (KAS) as the basis for a comprehensive electronic patient record and the switch in radiology to an integrated RIS solution. The third phase (2001-2006) addressed further implementation and development of clinical data management in which both regular documentation of patient data and information processing not related to patients are optimized by making use of Intranet/Internet technology. It includes the hospital wide implementation of PACS and the forthcoming phase of information processing increasingly shaped by workflow and decision support. (orig.) [de

  5. Photometric Modeling of a Cometary Nucleus: Taking Hapke Modeling to the Limit

    Science.gov (United States)

    Buratti, B. J.; Hicks, M. D.; Soderblom, L.; Hillier, J.; Britt, D.

    2002-01-01

    In the past two decades, photometric models developed by Bruce Hapke have been fit to a wide range of bodies in the Solar System: The Moon, Mercury, several asteroids, and many icy and rocky satellites. These models have enabled comparative descriptions of the physical attributes of planetary surfaces, including macroscopic roughness, particle size and size-distribution, the single scattering albedo, and the compaction state of the optically active portion of the regolith. One challenging type of body to observe and model, a cometary nucleus, awaited the first space based mission to obtain images unobscured by coma. The NASA-JPL Deep Space 1 Mission (DS1) encountered the short-period Jupiter-family comet 19/P Borrelly on September 22, 2001, about 8 days after perihelion. Prior to its closest approach of 2171 km, the remote-sensing package on the spacecraft obtained 25 CCD images of the comet, representing the first closeup, unobscured view of a comet's nucleus. At closest approach, corresponding to a resolution of 47 meters per pixel, the intensity of the coma was less than 1% of that of the nucleus. An unprecedented range of high solar phase angles (52-89 degrees), viewing geometries that are in general attainable only when a comet is active, enabled the first quantitative and disk-resolved modeling of surface photometric physical parameters.

  6. Photometric redshifts as a tool for studying the Coma cluster galaxy populations

    Science.gov (United States)

    Adami, C.; Ilbert, O.; Pelló, R.; Cuillandre, J. C.; Durret, F.; Mazure, A.; Picat, J. P.; Ulmer, M. P.

    2008-12-01

    Aims: We apply photometric redshift techniques to an investigation of the Coma cluster galaxy luminosity function (GLF) at faint magnitudes, in particular in the u* band where basically no studies are presently available at these magnitudes. Methods: Cluster members were selected based on probability distribution function from photometric redshift calculations applied to deep u^*, B, V, R, I images covering a region of almost 1 deg2 (completeness limit R ~ 24). In the area covered only by the u* image, the GLF was also derived after a statistical background subtraction. Results: Global and local GLFs in the B, V, R, and I bands obtained with photometric redshift selection are consistent with our previous results based on a statistical background subtraction. The GLF in the u* band shows an increase in the faint end slope towards the outer regions of the cluster. The analysis of the multicolor type spatial distribution reveals that late type galaxies are distributed in clumps in the cluster outskirts, where X-ray substructures are also detected and where the GLF in the u* band is steeper. Conclusions: We can reproduce the GLFs computed with classical statistical subtraction methods by applying a photometric redshift technique. The u* GLF slope is steeper in the cluster outskirts, varying from α ~ -1 in the cluster center to α ~ -2 in the cluster periphery. The concentrations of faint late type galaxies in the cluster outskirts could explain these very steep slopes, assuming a short burst of star formation in these galaxies when entering the cluster. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is also partly based on data products produced at

  7. Can We Include The Third Dimension During Image Mining?

    Indian Academy of Sciences (India)

    Retrieved images using only photometric features · Use of X-ratio · Results for a different query · Retrieval results with geometric and photometric features · Rail track retrieval · Recall and Precision · Retrieval Performance · Application II: Search Arts and Sports Photography · Examples of low DOF images · Typical Retrieval.

  8. Implementation and Validation of PACS Integrated Peer Review for Discrepancy Recording of Radiology Reporting

    NARCIS (Netherlands)

    Olthof, A. W.; van Ooijen, P. M. A.

    The purpose of this work is to demonstrate the possibility of implementation of a PACS-integrated peer review system based on RADPEER T classification providing a step-wise implementation plan utilizing features already present in the standard PACS implementation and without the requirement of

  9. PACS--and beyond. A journey to the digital promised land.

    Science.gov (United States)

    Viau, Mark A

    2004-01-01

    A successful picture archiving and communication system (PACS) integration depends on much more than the technology; marketing also plays a large role. This fact was evident from the inception of the PACS project at Boca Raton Community Hospital (BRCH). Strategic and effective marketing efforts should target technologists, nurses, physicians (including radiologists), administration, and colleagues in other departments. The buy-in of these users is critical to the project's success. BRCH's first marketing effort took place during the initial PACS presentation made to the hospital's board of directors. Once approval was given and a 6-month implementation target was set, a strategic and effective marketing/education plan commenced. Posters, brochures, t-shirts, and promotional items were distributed in a coordinated effort to target hospital staff and referring physician offices. Through its "Got PACS?" branding and other identity materials, BRCH implemented a marketing plan that informed, educated, and engaged PACS users.

  10. PACS for Bhutan: a cost effective open source architecture for emerging countries

    Directory of Open Access Journals (Sweden)

    Osman Ratib

    2016-07-01

    Full Text Available Abstract This paper reports the design and implementation of an innovative and cost-effective imaging management infrastructure suitable for radiology centres in emerging countries. It was implemented in the main referring hospital of Bhutan equipped with a CT, an MRI, digital radiology, and a suite of several ultrasound units. They lacked the necessary informatics infrastructure for image archiving and interpretation and needed a system for distribution of images to clinical wards. The solution developed for this project combines several open source software platforms in a robust and versatile archiving and communication system connected to analysis workstations equipped with a FDA-certified version of the highly popular Open-Source software. The whole system was implemented on standard off-the-shelf hardware. The system was installed in three days, and training of the radiologists as well as the technical and IT staff was provided onsite to ensure full ownership of the system by the local team. Radiologists were rapidly capable of reading and interpreting studies on the diagnostic workstations, which had a significant benefit on their workflow and ability to perform diagnostic tasks more efficiently. Furthermore, images were also made available to several clinical units on standard desktop computers through a web-based viewer. Messages/teaching points • Open source imaging informatics platforms can provide cost-effective alternatives for PACS • Robust and cost-effective open architecture can provide adequate solutions for emerging countries • Imaging informatics is often lacking in hospitals equipped with digital modalities

  11. Morpho-z: improving photometric redshifts with galaxy morphology

    Science.gov (United States)

    Soo, John Y. H.; Moraes, Bruno; Joachimi, Benjamin; Hartley, William; Lahav, Ofer; Charbonnier, Aldée; Makler, Martín; Pereira, Maria E. S.; Comparat, Johan; Erben, Thomas; Leauthaud, Alexie; Shan, Huanyuan; Van Waerbeke, Ludovic

    2018-04-01

    We conduct a comprehensive study of the effects of incorporating galaxy morphology information in photometric redshift estimation. Using machine learning methods, we assess the changes in the scatter and outlier fraction of photometric redshifts when galaxy size, ellipticity, Sérsic index, and surface brightness are included in training on galaxy samples from the SDSS and the CFHT Stripe-82 Survey (CS82). We show that by adding galaxy morphological parameters to full ugriz photometry, only mild improvements are obtained, while the gains are substantial in cases where fewer passbands are available. For instance, the combination of grz photometry and morphological parameters almost fully recovers the metrics of 5-band photometric redshifts. We demonstrate that with morphology it is possible to determine useful redshift distribution N(z) of galaxy samples without any colour information. We also find that the inclusion of quasar redshifts and associated object sizes in training improves the quality of photometric redshift catalogues, compensating for the lack of a good star-galaxy separator. We further show that morphological information can mitigate biases and scatter due to bad photometry. As an application, we derive both point estimates and posterior distributions of redshifts for the official CS82 catalogue, training on morphology and SDSS Stripe-82 ugriz bands when available. Our redshifts yield a 68th percentile error of 0.058(1 + z), and a outlier fraction of 5.2 per cent. We further include a deep extension trained on morphology and single i-band CS82 photometry.

  12. Photometric Observation and Light Curve Analysis of Binary System ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Photometric Observation and Light Curve Analysis of Binary System ER-Orionis ... February to April 2008 with the 51 cm telescope of Biruni Observatory of Shiraz University in U, B and V filters (Johnson system) and an RCA 4509 photomultiplier. ... Articles are also visible in Web of Science immediately.

  13. Photometric Study of Fourteen Low-mass Binaries

    International Nuclear Information System (INIS)

    Korda, D.; Zasche, P.; Wolf, M.; Kučáková, H.; Vraštil, J.; Hoňková, K.

    2017-01-01

    New CCD photometric observations of fourteen short-period low-mass eclipsing binaries (LMBs) in the photometric filters I, R, and V were used for a light curve analysis. A discrepancy remains between observed radii and those derived from the theoretical modeling for LMBs, in general. Mass calibration of all observed LMBs was performed using only the photometric indices. The light curve modeling of these selected systems was completed, yielding the new derived masses and radii for both components. We compared these systems with the compilation of other known double-lined LMB systems with uncertainties of masses and radii less then 5%, which includes 66 components of binaries where both spectroscopy and photometry were combined together. All of our systems are circular short-period binaries, and for some of them, the photospheric spots were also used. A purely photometric study of the light curves without spectroscopy seems unable to achieve high enough precision and accuracy in the masses and radii to act as meaningful test of the M–R relation for low-mass stars.

  14. Classical variables in the era of space photometric missions

    Directory of Open Access Journals (Sweden)

    Molnár L.

    2015-01-01

    Full Text Available The space photometric missions like CoRoT and Kepler transformed our view of pulsating stars, including the well-known RR Lyrae and Cepheid classes. The K2, TESS and PLATO missions will expand these investigations to larger sample sizes and to specific stellar populations.

  15. Solving the uncalibrated photometric stereo problem using total variation

    DEFF Research Database (Denmark)

    Quéau, Yvain; Lauze, Francois Bernard; Durou, Jean-Denis

    2013-01-01

    In this paper we propose a new method to solve the problem of uncalibrated photometric stereo, making very weak assumptions on the properties of the scene to be reconstructed. Our goal is to solve the generalized bas-relief ambiguity (GBR) by performing a total variation regularization of both...

  16. Photometric observations of Earth-impacting asteroid 2008 TC(3)

    Czech Academy of Sciences Publication Activity Database

    Kozubal, M.; Gasdia, F.W.; Dantowitz, R.; Scheirich, Peter; Harris, A. W.

    2011-01-01

    Roč. 46, č. 4 (2011), s. 534-542 ISSN 1086-9379 Institutional research plan: CEZ:AV0Z10030501 Keywords : asteroid * photometric observations Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.719, year: 2011

  17. PHOTOMETRIC EVIDENCE FOR THE OSMOTIC BEHAVIOR OF RAT LIVER MICROSOMES

    Science.gov (United States)

    Tedeschi, Henry; James, Joseph M.; Anthony, William

    1963-01-01

    Electron microscope observations are consistent with the interpretation that the elements of the endoplasmic reticulum are osmotically active in situ as well as after isolation. More recently, it has been reported that microsomal suspensions equilibrate almost completely with added C14-sucrose and that no osmotic behavior is evident from photometric data. These findings were considered at variance with the electron microscope data. However, equilibration with added label simply attests to a relatively high permeability, and, in addition, the photometric data need not be critical. Osmotic volume changes, measured photometrically, may be masked by concomitant events (e.g., changes in the refractive index of the test solutions at varying osmotic pressures, breakdown of the particles, and agglutination). For these reasons the photometric experiments were repeated. In this work, the reciprocal of optical density of microsomal suspensions was found to vary linearly with the reciprocal of concentration of the medium at constant refractive index. These changes probably correspond to osmotic volume changes, since the effect was found to be (a) independent of substance used and (b) osmotically reversible. The transmission of the suspension was found to vary with the refractive index of the medium, the concentration of particles, and the wavelength of incident light, according to relationships that are similar to or identical with those obtained for mitochondrial suspensions. PMID:14064105

  18. Photometric Study of Fourteen Low-mass Binaries

    Energy Technology Data Exchange (ETDEWEB)

    Korda, D.; Zasche, P.; Wolf, M.; Kučáková, H.; Vraštil, J. [Astronomical Institute, Charles University, Faculty of Mathematics and Physics, CZ-180 00, Praha 8, V Holešovičkách 2 (Czech Republic); Hoňková, K., E-mail: korda@sirrah.troja.mff.cuni.cz [Variable Star and Exoplanet Section of Czech Astronomical Society, Vsetínská 941/78, CZ-757 01, Valašské Meziříčí (Czech Republic)

    2017-07-01

    New CCD photometric observations of fourteen short-period low-mass eclipsing binaries (LMBs) in the photometric filters I, R, and V were used for a light curve analysis. A discrepancy remains between observed radii and those derived from the theoretical modeling for LMBs, in general. Mass calibration of all observed LMBs was performed using only the photometric indices. The light curve modeling of these selected systems was completed, yielding the new derived masses and radii for both components. We compared these systems with the compilation of other known double-lined LMB systems with uncertainties of masses and radii less then 5%, which includes 66 components of binaries where both spectroscopy and photometry were combined together. All of our systems are circular short-period binaries, and for some of them, the photospheric spots were also used. A purely photometric study of the light curves without spectroscopy seems unable to achieve high enough precision and accuracy in the masses and radii to act as meaningful test of the M–R relation for low-mass stars.

  19. The Young Solar Analogs Project: Initial Photometric Results

    Science.gov (United States)

    Saken, Jon M.; Gray, R. O.; Corbally, C. J.

    2013-06-01

    Since 2007 we have been conducting spectroscopic monitoring of the Ca II H & K lines and G-band for a sample of 31 YSAs in order to better understand their activity cycles and variations, as well as the effects of young stars on their solar systems. The targets cover the spectral range of stars most likely to contain Earth analogs, F8-K2, and a broad enough range of ages, 0.3 Gyr - 1.5 Gyr, to investigate how activity level changes with stellar age. These studies are already showing possible evidence for activity cycles, large variations in starspot activity, and flaring events. In order to obtain a more complete picture of the nature of the stars' activity and examine the correlations between stellar brightness and chromospheric activity, we have started a complimentary campaign of photometric monitoring of these targets in Johnson B, V, and R, Stromgren v and H-alpha, with the use of a small robotic telescope dedicated to this project. This poster will present some results from the first year of photometric monitoring, focusing on the correlations between the photometric bands, and between the photometric and spectroscopic data, as well as an investigation of short-term (1-2 minutes) spectroscopic variations using data obtained earlier this year on the 1.8 m Vatican Advanced Technology Telescope (VATT).

  20. Photometric Observation and Light Curve Analysis of Binary System ...

    Indian Academy of Sciences (India)

    Abstract. Photometric observations of the over-contact binary ER ORI were performed during November 2007 and February to April 2008 with the 51cm telescope of Biruni Observatory of Shiraz University in U, B and V filters (Johnson system) and an RCA 4509 photomultiplier. We used these data to obtain the light curves ...

  1. On the Photometric Error Calibration for the Differential Light Curves ...

    Indian Academy of Sciences (India)

    a value of 1.75 was estimated using the DLCs derived for pairs of steady stars ... apparently steady comparison stars present on the same CCD frame. ...... (2)) on the 262 steady star–star DLCs after accounting for the photometric error.

  2. Evolutionistic or revolutionary paths? A PACS maturity model for strategic situational planning.

    Science.gov (United States)

    van de Wetering, Rogier; Batenburg, Ronald; Lederman, Reeva

    2010-07-01

    While many hospitals are re-evaluating their current Picture Archiving and Communication System (PACS), few have a mature strategy for PACS deployment. Furthermore, strategies for implementation, strategic and situational planning methods for the evolution of PACS maturity are scarce in the scientific literature. Consequently, in this paper we propose a strategic planning method for PACS deployment. This method builds upon a PACS maturity model (PMM), based on the elaboration of the strategic alignment concept and the maturity growth path concept previously developed in the PACS domain. First, we review the literature on strategic planning for information systems and information technology and PACS maturity. Secondly, the PMM is extended by applying four different strategic perspectives of the Strategic Alignment Framework whereupon two types of growth paths (evolutionistic and revolutionary) are applied that focus on a roadmap for PMM. This roadmap builds a path to get from one level of maturity and evolve to the next. An extended method for PACS strategic planning is developed. This method defines eight distinctive strategies for PACS strategic situational planning that allow decision-makers in hospitals to decide which approach best suits their hospitals' current situation and future ambition and what in principle is needed to evolve through the different maturity levels. The proposed method allows hospitals to strategically plan for PACS maturation. It is situational in that the required investments and activities depend on the alignment between the hospital strategy and the selected growth path. The inclusion of both strategic alignment and maturity growth path concepts make the planning method rigorous, and provide a framework for further empirical research and clinical practice.

  3. 21 CFR 862.2160 - Discrete photometric chemistry analyzer for clinical use.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Discrete photometric chemistry analyzer for... Clinical Laboratory Instruments § 862.2160 Discrete photometric chemistry analyzer for clinical use. (a) Identification. A discrete photometric chemistry analyzer for clinical use is a device intended to duplicate...

  4. PHOTOMETRIC SUPERNOVA COSMOLOGY WITH BEAMS AND SDSS-II

    Energy Technology Data Exchange (ETDEWEB)

    Hlozek, Renee [Oxford Astrophysics, Department of Physics, University of Oxford, Keble Road, Oxford, OX1 3RH (United Kingdom); Kunz, Martin [Department de physique theorique, Universite de Geneve, 30, quai Ernest-Ansermet, CH-1211 Geneve 4 (Switzerland); Bassett, Bruce; Smith, Mat; Newling, James [African Institute for Mathematical Sciences, 68 Melrose Road, Muizenberg 7945 (South Africa); Varughese, Melvin [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch, Cape Town, 7700 (South Africa); Kessler, Rick; Frieman, Joshua [The Kavli Institute for Cosmological Physics, The University of Chicago, 933 East 56th Street, Chicago, IL 60637 (United States); Bernstein, Joseph P.; Kuhlmann, Steve; Marriner, John [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Campbell, Heather; Lampeitl, Hubert; Nichol, Robert C. [Institute of Cosmology and Gravitation, Dennis Sciama Building Burnaby Road Portsmouth PO1 3FX (United Kingdom); Dilday, Ben [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Goleta, CA 93117 (United States); Falck, Bridget; Riess, Adam G. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Sako, Masao [Department of Physics and Astronomy, University of Pennsylvania, 203 South 33rd Street, Philadelphia, PA 19104 (United States); Schneider, Donald P., E-mail: rhlozek@astro.princeton.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2012-06-20

    Supernova (SN) cosmology without spectroscopic confirmation is an exciting new frontier, which we address here with the Bayesian Estimation Applied to Multiple Species (BEAMS) algorithm and the full three years of data from the Sloan Digital Sky Survey II Supernova Survey (SDSS-II SN). BEAMS is a Bayesian framework for using data from multiple species in statistical inference when one has the probability that each data point belongs to a given species, corresponding in this context to different types of SNe with their probabilities derived from their multi-band light curves. We run the BEAMS algorithm on both Gaussian and more realistic SNANA simulations with of order 10{sup 4} SNe, testing the algorithm against various pitfalls one might expect in the new and somewhat uncharted territory of photometric SN cosmology. We compare the performance of BEAMS to that of both mock spectroscopic surveys and photometric samples that have been cut using typical selection criteria. The latter typically either are biased due to contamination or have significantly larger contours in the cosmological parameters due to small data sets. We then apply BEAMS to the 792 SDSS-II photometric SNe with host spectroscopic redshifts. In this case, BEAMS reduces the area of the {Omega}{sub m}, {Omega}{sub {Lambda}} contours by a factor of three relative to the case where only spectroscopically confirmed data are used (297 SNe). In the case of flatness, the constraints obtained on the matter density applying BEAMS to the photometric SDSS-II data are {Omega}{sup BEAMS}{sub m} = 0.194 {+-} 0.07. This illustrates the potential power of BEAMS for future large photometric SN surveys such as Large Synoptic Survey Telescope.

  5. PHOTOMETRIC SUPERNOVA COSMOLOGY WITH BEAMS AND SDSS-II

    International Nuclear Information System (INIS)

    Hlozek, Renée; Kunz, Martin; Bassett, Bruce; Smith, Mat; Newling, James; Varughese, Melvin; Kessler, Rick; Frieman, Joshua; Bernstein, Joseph P.; Kuhlmann, Steve; Marriner, John; Campbell, Heather; Lampeitl, Hubert; Nichol, Robert C.; Dilday, Ben; Falck, Bridget; Riess, Adam G.; Sako, Masao; Schneider, Donald P.

    2012-01-01

    Supernova (SN) cosmology without spectroscopic confirmation is an exciting new frontier, which we address here with the Bayesian Estimation Applied to Multiple Species (BEAMS) algorithm and the full three years of data from the Sloan Digital Sky Survey II Supernova Survey (SDSS-II SN). BEAMS is a Bayesian framework for using data from multiple species in statistical inference when one has the probability that each data point belongs to a given species, corresponding in this context to different types of SNe with their probabilities derived from their multi-band light curves. We run the BEAMS algorithm on both Gaussian and more realistic SNANA simulations with of order 10 4 SNe, testing the algorithm against various pitfalls one might expect in the new and somewhat uncharted territory of photometric SN cosmology. We compare the performance of BEAMS to that of both mock spectroscopic surveys and photometric samples that have been cut using typical selection criteria. The latter typically either are biased due to contamination or have significantly larger contours in the cosmological parameters due to small data sets. We then apply BEAMS to the 792 SDSS-II photometric SNe with host spectroscopic redshifts. In this case, BEAMS reduces the area of the Ω m , Ω Λ contours by a factor of three relative to the case where only spectroscopically confirmed data are used (297 SNe). In the case of flatness, the constraints obtained on the matter density applying BEAMS to the photometric SDSS-II data are Ω BEAMS m = 0.194 ± 0.07. This illustrates the potential power of BEAMS for future large photometric SN surveys such as Large Synoptic Survey Telescope.

  6. Report on the 2005 Particle Accelerator Conference (PAC05)

    International Nuclear Information System (INIS)

    Kathy F. Rosenbalm

    2005-01-01

    The 21st Particle Accelerator Conference, PAC05, took place at the Knoxville Convention Center (KCC) from Monday through Friday, May 16-20, 2005. Sponsored by the American Physical Society (APS), the Institute of Electrics and Electronics Engineers (IEEE) with its subdivision of Nuclear and Plasma Sciences Society (NPSS), the conference was hosted by the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) Project and Thomas Jefferson National Accelerator Facility (JLab). The conference was chaired by Norbert Holtkamp, and the Local Organizing Committee was made up of staff from the ORNL SNS Project under the chairmanship of Stuart Henderson. The conference welcomed over 1400 delegates from the United States, Europe, Asia, the Middle East, South America and from as far away as Australia. Almost 1400 papers where processed during the conference and will be published on the Joint Accelerator Conferences Website (JACoW) page

  7. PAC study of ionic motion in silver compound superionic conductors

    International Nuclear Information System (INIS)

    Mekata, M.; Seguchi, Y.

    1983-01-01

    Ionic motion in superionic conductors, Ag 2 S, Ag 2 Se and Ag 3 SI was investigated by γ-γ PAC on 111 Cd. Diffusion constant measurements showed that probe ions migrate almost as fast as Ag + ions above 500 K in Ag 2 S and Ag 2 Se and above 700 K in Ag 3 SI. Multivalent impurities were found to be unstable in AgI and Ag 2 Te. The correlation time of ionic motion was deduced from the observed relaxation rate together with the diffusion constants. The correlation time and its activation energy increase in order of Ag 2 S, Ag 2 Se and Ag 3 SI. The flight distance of Ag + ions remains almost constant in the measured temperature range. (Auth.)

  8. Proceedings of the 22nd Particle Accelerator Conference (PAC'07)

    International Nuclear Information System (INIS)

    2007-01-01

    The twenty-second Particle Accelerator Conference, PAC'07, took place at the Albuquerque Convention Centre in Albuquerque, the largest city in New Mexico, from Monday to Friday, 2007 June 25 to 29. It was attended by over 1350 delegates from 25 different countries (63% North America, 24% Europe, 11% Asia and 2% Other), and was held under the auspices of the two professional societies that oversee and make holding this series of conferences possible, the Division of Physics of Beams within APS, and the Nuclear and Plasma Sciences Society within IEEE. As host of the conference, Los Alamos National Laboratory (LANL) is especially thanked for their many contributions and assistance both prior to and during the conference. The Convention Center was an ideal location for information sharing and discussions between the interdisciplinary aspects of the accelerator community, as well as for related meetings and ad-hoc 'rump' sessions.

  9. Implementation of a PC based picture archival and communications system (PACS) in Nuclear Medicine

    International Nuclear Information System (INIS)

    Kelly, M.J.; Van Every, B.

    1998-01-01

    Full text: Nuclear Medicine produces images with relatively low spatial resolution and very high contrast, which lend themselves more easily to digital acquisition, display, manipulation and storage than other forms of medical imaging. This poster describes improvements in Nuclear Medicine service delivery and efficiency which have resulted from an implementation of this technology over recent years. All 'save screen' data, gated blood pool scans and selected dynamic data from four gamma cameras of two vendors is automatically archived to a single Pentium 200 MHz PC for permanent hard disk archival. Two years of data is already stored on line throughout the PC network in a Microsoft Access ODBC 'Medvision' database, and accessible via modem using 'PC Anywhere' software. Images are exported as Bitmaps to be included in typed reports for printing or direct Fax transmission to wards or Dr's offices on the same day that a service is provided. For out of hours services, this system enables a typed report and image to go with the patient to the ward from Nuclear Medicine, with prior consultant review being provided by modem when not immediately available on site. Computer enhanced comparisons with all archived studies can be performed within 30 secs, for improved assessment of serial progress. As the hard disk storage cost of images is now less than 10% of film costs, and falling, transition to filmless reporting appears inevitable. 'Dicom' Software compatibility, currently available through a Unix workstation, should permit integration with a future Radiology PACS These changes assist in maintaining service quality, while both eliminating delays in providing reports and reducing costs

  10. Black box integration of computer-aided diagnosis into PACS deserves a second chance: results of a usability study concerning bone age assessment.

    Science.gov (United States)

    Geldermann, Ina; Grouls, Christoph; Kuhl, Christiane; Deserno, Thomas M; Spreckelsen, Cord

    2013-08-01

    Usability aspects of different integration concepts for picture archiving and communication systems (PACS) and computer-aided diagnosis (CAD) were inquired on the example of BoneXpert, a program determining the skeletal age from a left hand's radiograph. CAD-PACS integration was assessed according to its levels: data, function, presentation, and context integration focusing on usability aspects. A user-based study design was selected. Statements of seven experienced radiologists using two alternative types of integration provided by BoneXpert were acquired and analyzed using a mixed-methods approach based on think-aloud records and a questionnaire. In both variants, the CAD module (BoneXpert) was easily integrated in the workflow, found comprehensible and fitting in the conceptual framework of the radiologists. Weak points of the software integration referred to data and context integration. Surprisingly, visualization of intermediate image processing states (presentation integration) was found less important as compared to efficient handling and fast computation. Seamlessly integrating CAD into the PACS without additional work steps or unnecessary interrupts and without visualizing intermediate images may considerably improve software performance and user acceptance with efforts in time.

  11. Multimedia consultation session recording and playback using Java-based browser in global PACS

    Science.gov (United States)

    Martinez, Ralph; Shah, Pinkesh J.; Yu, Yuan-Pin

    1998-07-01

    The current version of the Global PACS software system uses a Java-based implementation of the Remote Consultation and Diagnosis (RCD) system. The Java RCD includes a multimedia consultation session between physicians that includes text, static image, image annotation, and audio data. The JAVA RCD allows 2-4 physicians to collaborate on a patient case. It allows physicians to join the session via WWW Java-enabled browsers or stand alone RCD application. The RCD system includes a distributed database archive system for archiving and retrieving patient and session data. The RCD system can be used for store and forward scenarios, case reviews, and interactive RCD multimedia sessions. The RCD system operates over the Internet, telephone lines, or in a private Intranet. A multimedia consultation session can be recorded, and then played back at a later time for review, comments, and education. A session can be played back using Java-enabled WWW browsers on any operating system platform. The JAVA RCD system shows that a case diagnosis can be captured digitally and played back with the original real-time temporal relationships between data streams. In this paper, we describe design and implementation of the RCD session playback.

  12. Radial velocity variations of photometrically quiet, chromospherically inactive Kepler stars: A link between RV jitter and photometric flicker

    Energy Technology Data Exchange (ETDEWEB)

    Bastien, Fabienne A.; Stassun, Keivan G.; Pepper, Joshua [Physics and Astronomy Department, Vanderbilt University, 1807 Station B, Nashville, TN 37235 (United States); Wright, Jason T. [Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16803 (United States); Aigrain, Suzanne [Sub-department of Astrophysics, Department of Physics, University of Oxford, Oxford OX1 3RH (United Kingdom); Basri, Gibor [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Johnson, John A. [Department of Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Howard, Andrew W. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Walkowicz, Lucianne M. [Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544 (United States)

    2014-02-01

    We compare stellar photometric variability, as measured from Kepler light curves by Basri et al., with measurements of radial velocity (RV) rms variations of all California Planet Search overlap stars. We newly derive rotation periods from the Kepler light curves for all of the stars in our study sample. The RV variations reported herein range from less than 4 to 135 m s{sup –1}, yet the stars all have amplitudes of photometric variability less than 3 mmag, reflecting the preference of the RV program for chromospherically 'quiet' stars. Despite the small size of our sample, we find with high statistical significance that the RV rms manifests strongly in the Fourier power spectrum of the light curve: stars that are noisier in RV have a greater number of frequency components in the light curve. We also find that spot models of the observed light curves systematically underpredict the observed RV variations by factors of ∼2-1000, likely because the low-level photometric variations in our sample are driven by processes not included in simple spot models. The stars best fit by these models tend to have simpler