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Sample records for vxr-12 digitizer performances

  1. Evaluation of the vidar`s VXR-12 digitizer performances for film dosimetry of beams delimited by multileaf collimator

    Energy Technology Data Exchange (ETDEWEB)

    Julia, F [Centre de Lutte Contre le Cancer Gustave-Roussy, 94 - Villejuif (France); Briot, E

    1995-12-01

    The development of new irradiation techniques such as conformal radiotherapy increasingly implies the use of a multileaf collimator. The measurement of dose gradients in the penumbra region, and of dose distributions at the edge of complex shaped fields defined by multileaf collimators requires a high definition dosimetric method. Nowadays film digitizers have been notably improved and allow the film dosimetry to be faster, more accurate, presenting a sensitivity and high spatial resolution. To be able to perform the study of physical and dosimetric specifications of a multileaf collimator, we have evaluated the performances of the Vidar VCR-12 digitizer, with respect to its sensitivity, linearity, optical density range and the resolution. These performances were compared with the performances of different systems already in use in our department, either manual or automatic, using specific patterns. The main limitation for dosimetric use is the detection threshold that can introduce errors in isodose calculation, especially for the lowest values. The result of the intercomparisons have allowed corrections to be added, taking into account this Vidar problem. The results obtained after correction for the dose profiles of squared fields are in good agreement with ionization chamber measurements in a water phantom. It is concluded that Vidar digitizer is suitable for the use of film dosimetry for the dose distributions in fields defined by multileaf collimator.

  2. Characteristics of a commercially available film digitizer and their significance for film dosimetry

    International Nuclear Information System (INIS)

    Mersseman, B.; De Wagter, C.

    1998-01-01

    Dosimetric detectors used in high-energy photon radiation dosimetry mainly perform a zero- or one-dimensional measurement. These low-dimensional methods are not always adequate in the context of conformal radiotherapy. Therefore, two-dimensional film dosimetry has attracted attention. We studied a 12-bit CCD-based film digitizer (Vidar VXR-12) with regard to accurate film dosimetry. We investigated the stability, linearity, noise, effects of aberrant light scatter and built-in conversion tables. A digitizing resolution of 75 dpi and a digitizing speed of 20 ms/line result in an optimal signal-to-noise ratio. At optical densities above 2.0, the reading accuracy of the digitizer is limited by noise. The results of various experiments prove both the capabilities and limitations of the digitizer studied. We also propose a method to acquire and process film data using such a digitizer. (author)

  3. Performing Digital Literature

    Directory of Open Access Journals (Sweden)

    Jerome Fletcher

    2015-11-01

    Full Text Available Digital literature is a complex assemblage of related elements –material, spatial, linguistic, performative, textual, cultural, social– each of which is at one time interdependent and detached. This article discusses the literary creation within the cyberculture from the performativity point of view in relation to the textual apparatus. This is done through the analysis of a selection of performances where physical corporeality has a collaborative function with the body to a greater or lesser degree. Therefore, this physical feature can not only change, but stand at three possible and hybridizable axes: 1 the digital text as protagonist, 2 the digital text as counterpart, and 3 the digital text as site.

  4. High Performance Proactive Digital Forensics

    International Nuclear Information System (INIS)

    Alharbi, Soltan; Traore, Issa; Moa, Belaid; Weber-Jahnke, Jens

    2012-01-01

    With the increase in the number of digital crimes and in their sophistication, High Performance Computing (HPC) is becoming a must in Digital Forensics (DF). According to the FBI annual report, the size of data processed during the 2010 fiscal year reached 3,086 TB (compared to 2,334 TB in 2009) and the number of agencies that requested Regional Computer Forensics Laboratory assistance increasing from 689 in 2009 to 722 in 2010. Since most investigation tools are both I/O and CPU bound, the next-generation DF tools are required to be distributed and offer HPC capabilities. The need for HPC is even more evident in investigating crimes on clouds or when proactive DF analysis and on-site investigation, requiring semi-real time processing, are performed. Although overcoming the performance challenge is a major goal in DF, as far as we know, there is almost no research on HPC-DF except for few papers. As such, in this work, we extend our work on the need of a proactive system and present a high performance automated proactive digital forensic system. The most expensive phase of the system, namely proactive analysis and detection, uses a parallel extension of the iterative z algorithm. It also implements new parallel information-based outlier detection algorithms to proactively and forensically handle suspicious activities. To analyse a large number of targets and events and continuously do so (to capture the dynamics of the system), we rely on a multi-resolution approach to explore the digital forensic space. Data set from the Honeynet Forensic Challenge in 2001 is used to evaluate the system from DF and HPC perspectives.

  5. Digital breast tomosynthesis versus digital mammography: a clinical performance study

    International Nuclear Information System (INIS)

    Gennaro, Gisella; Baldan, Enrica; Bezzon, Elisabetta; Polico, Ilaria; Proietti, Alessandro; Toffoli, Aida; Toledano, Alicia; Di Maggio, Cosimo; La Grassa, Manuela; Pescarini, Luigi; Muzzio, Pier Carlo

    2010-01-01

    To compare the clinical performance of digital breast tomosynthesis (DBT) with that of full-field digital mammography (FFDM) in a diagnostic population. The study enrolled 200 consenting women who had at least one breast lesion discovered by mammography and/or ultrasound classified as doubtful or suspicious or probably malignant. They underwent tomosynthesis in one view [mediolateral oblique (MLO)] of both breasts at a dose comparable to that of standard screen-film mammography in two views [craniocaudal (CC) and MLO]. Images were rated by six breast radiologists using the BIRADS score. Ratings were compared with the truth established according to the standard of care and a multiple-reader multiple-case (MRMC) receiver-operating characteristic (ROC) analysis was performed. Clinical performance of DBT compared with that of FFDM was evaluated in terms of the difference between areas under ROC curves (AUCs) for BIRADS scores. Overall clinical performance with DBT and FFDM for malignant versus all other cases was not significantly different (AUCs 0.851 vs 0.836, p = 0.645). The lower limit of the 95% CI or the difference between DBT and FFDM AUCs was -4.9%. Clinical performance of tomosynthesis in one view at the same total dose as standard screen-film mammography is not inferior to digital mammography in two views. (orig.)

  6. Performance of the Lep Time Digitizer (LTD)

    International Nuclear Information System (INIS)

    Berst, J.D.; Colledani, C.; Loukas, D.

    1988-01-01

    Performance of the fastbus digitizer to be used for signal digitizing in the DELPHI detectors is described. Two prototypes, a 128 multihit capability device and a 256 capability device were tested. Test results show that the digitizer works properly. A very good stability is achieved in the range of + 150 mV from the nominal (-2V) supply with the total number of lost hits of the order of 10 -6 either in veto or non veto mode. The optimum clock frequency strongly depends on the gates used as delay elements. With the gates of the first prototype, the optimum frequencies obtained are 117 MHz for the first prototype, and 112 MHz for the second. Output linearity is excellent

  7. Why is digit ratio correlated to sports performance?

    Science.gov (United States)

    Kim, Tae Beom; Kim, Khae Hawn

    2016-12-01

    Second to fourth digit ratio is the ratio of second to fourth digit length. It has been known that digit ratio is sexually dimorphic in humans, such that males tend to have lower digit ratio (longer fourth digits relative to second digits) than females. Digit ratio is thought to be a biomarker of the balance between fetal testosterone (FT) and fetal estrogen (FE) in a relatively narrow developmental window at the end of the first trimester of pregnancy. On the contrary, the relationships between digit ratio and levels of sex steroids in adults are not clear. Most correlational studies between digit ratio and adult sex steroids have revealed that this association is statistically not significant. However, for many years, a lot of researches showed negative relationships between digit ratio and sports performance such as rugby, surfing, rowing, sprinting, endurance, and hand grip strength. Here, we discuss possible mechanisms about the relationships between digit ratio and sports performance.

  8. Library performance measurement in the digital age

    OpenAIRE

    Conyers, A.; Payne, Philip

    2011-01-01

    Book synopsis: University libraries around the world have embraced the possibilities of the digital learning environment, facilitating its use and proactively seeking to develop the provision of electronic resources and services. The digital environment offers opportunities and challenges for librarians in all aspects of their work - in information literacy, virtual reference, institutional repositories, e-learning, managing digital resources and social media. The authors in this timely book ...

  9. Digital Image Correlation for Performance Monitoring

    Science.gov (United States)

    Palaviccini, Miguel; Turner, Dan; Herzberg, Michael

    2016-01-01

    Evaluating the health of a mechanism requires more than just a binary evaluation of whether an operation was completed. It requires analyzing more comprehensive, full-field data. Health monitoring is a process of non-destructively identifying characteristics that indicate the fitness of an engineered component. In order to monitor unit health in a production setting, an automated test system must be created to capture the motion of mechanism parts in a real-time and non-intrusive manner. One way to accomplish this is by using high-speed video and Digital Image Correlation (DIC). In this approach, individual frames of the video are analyzed to track the motion of mechanism components. The derived performance metrics allow for state-of-health monitoring and improved fidelity of mechanism modeling. The results are in-situ state-of-health identification and performance prediction. This paper introduces basic concepts of this test method, and discusses two main themes: the use of laser marking to add fiducial patterns to mechanism components, and new software developed to track objects with complex shapes, even as they move behind obstructions. Finally, the implementation of these tests into an automated tester is discussed.

  10. Performance Analysis of Digital loudspeaker Arrays

    DEFF Research Database (Denmark)

    Pedersen, Bo Rohde; Kontomichos, Fotios; Mourjopoulos, John

    2008-01-01

    An analysis of digital loudspeaker arrays shows that the ways in which bits are mapped to the drivers influence the quality of the audio result. Specifically, a "bit-summed" rather than the traditional "bit-mapped" strategy greatly reduces the number of times drivers make binary transitions per...... period of the input frequency. Detailed simulations compare the results for a 32-loudspeaker array with a similar configuration with analog excitation of the drivers. Ideally, drivers in digital arrays should be very small and span a small area, but that sets limits on the low-frequency response...

  11. Total cost of performing analog-to-digital upgrades

    International Nuclear Information System (INIS)

    Albrigo, T.

    1993-01-01

    The financial well-being of nuclear power plants in the United States is dependent on reducing costs. Rapid advances in industrial technology have created a conundrum for utility executives and their engineering staffs. Digital technology is being touted as beneficial in many ways; however, a number of significant issues have been raised regarding the adequacy and financial viability of digital systems in nuclear power plants. Actual or perceived problems with digital system design, development, and installation have caused significant financial losses for nuclear utilities. This paper provides a list of problems that must be considered in performing an analog-to-digital conversion or for doing a large digital upgrade. It is desirable that the full financial risks associated with these types of upgrades are considered. Specific problems encountered at Palo Verde nuclear generating station are reviewed to emphasize some of the problem areas

  12. High Performance Low Cost Digitally Controlled Power Conversion Technology

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes

    2008-01-01

    in order to reduce the power consumption of servers and datacenters. The work presented in this thesis includes digital control methods for switch-mode converters implemented in microcontrollers, digital signal controllers and field programmable gate arrays. Microcontrollers are cheap devices that can...... be used for real-time control of switch-mode converters. Software design in the assembly language of the microcontroller is important because of the limited resources of the microcontroller. Microcontrollers are best suited for power electronics applications with low bandwidth requirements because...... the execution time of the software algorithm that realises the digital control law will constitute a considerable delay in the control loop. Digital signal controllers are powerful devices capable of performing arithmetic functions much faster than a microcontroller can. Digital signal controllers are well...

  13. Empirical Investigation of Key Business Factors for Digital Game Performance

    OpenAIRE

    Aleem, Saiqa; Capretz, Luiz Fernando; Ahmed, Faheem

    2015-01-01

    Game development is an interdisciplinary concept that embraces software engineering, business, management, and artistic disciplines. This research facilitates a better understanding of the business dimension of digital games. The main objective of this research is to investigate empirically the effect of business factors on the performance of digital games in the market and to answer the research questions asked in this study. Game development organizations are facing high pressure and compet...

  14. Comparing the performance of three digital forensic tools

    Directory of Open Access Journals (Sweden)

    Brian Cusack

    Full Text Available Software used for digital forensic investigations requires to be verified against reliability and validity criteria. In this paper, three well known tools are tested against the mandatory features of digital forensic tools published by the National Institute of Standards (NIST. It was found that a variation in performance existed between the tools, with all having measureable areas of non performance. The findings have an impact on the professional use of the tools and illustrate the need for benchmarking and testing of the tools before use.

  15. Perspectives of creators and performers on the digital era

    NARCIS (Netherlands)

    Poort, J.; Akker, I.; Rutten, P.; Weda, J.

    2015-01-01

    In this contribution, a nearly comprehensive survey among creators and performers in media, arts and entertainment in the Netherlands is presented. It concerns the implications of digital reproduction and distribution for the creative professions as perceived by those working in it. Based on

  16. Perspectives of Creators and Performers on the Digital Era

    NARCIS (Netherlands)

    Poort, J.; Weda, J.; Akker, I.; Rutten, P.

    2013-01-01

    In this contribution, a nearly comprehensive survey among creators and performers in media, arts and entertainment in the Netherlands is presented. It concerns the implications of digital reproduction and distribution for the creative professions as perceived by those working in it. Based on

  17. Digital Technologies and performative pedagogies: Repositioning the visual

    Directory of Open Access Journals (Sweden)

    Kathryn Grushka

    2010-05-01

    Full Text Available Images are becoming a primary means of information presentation in the digitized global media and digital technologies have emancipated and democratized the image. This allows for the reproduction and manipulation of images on a scale never seen before and opens new possibilities for teachers schooled in critical visuality. This paper reports on an innovative pre-service teacher training course in which a cross-curricula cohort of secondary teachers employed visual performative competencies to produce a series of learning objects on a digital platform. The resulting intertextual narratives demonstrate that the manipulation of image and text offered by digital technologies create a powerful vehicle for investigating knowledge and understandings, evolving new meaning and awakening latent creativity in the use of images for meaning making. This research informs the New Literacies and multimodal fields of enquiry and argues that visuality is integral to any pedagogy that purports to be relevant to the contemporary learner. It argues that the visual has been significantly under-valued as a conduit for knowledge acquisition and meaning making in the digital environment and supports the claim that critical literacy, interactivity, experimentation and production are vital to attaining the tenets of transformative education (Buckingham, 2007; Walsh, 2007; Cope & Kalantzis, 2008.

  18. Volumetric breast density affects performance of digital screening mammography

    OpenAIRE

    Wanders, JO; Holland, K; Veldhuis, WB; Mann, RM; Pijnappel, RM; Peeters, PH; Van Gils, CH; Karssemeijer, N

    2016-01-01

    PURPOSE: To determine to what extent automatically measured volumetric mammographic density influences screening performance when using digital mammography (DM). METHODS: We collected a consecutive series of 111,898 DM examinations (2003-2011) from one screening unit of the Dutch biennial screening program (age 50-75 years). Volumetric mammographic density was automatically assessed using Volpara. We determined screening performance measures for four density categories comparable to the Ameri...

  19. Performances of different digital mammography imaging systems: Evaluation and comparison

    Energy Technology Data Exchange (ETDEWEB)

    Bisogni, M.G. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy)]. E-mail: giuseppina.bisogni@pi.infn.it; Bulajic, D. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); International Centre for Theoretical Physics, Trieste (Italy); Delogu, P. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Fantacci, M.E. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Novelli, M. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Quattrocchi, M. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Rosso, V. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy); Stefanini, A. [Dipartimento di Fisica ' E. Fermi' , Universita di Pisa, e Sezione INFN di Pisa, Pisa (Italy)

    2005-07-01

    Digital mammography is entering routine clinical use and many commercial systems are now in use in the radiological units for screening and diagnostic mammography. At the same time, the research in the digital mammography field is very active in the development of more and more performing devices. In this paper we present the performance of single photon counting pixel detectors (MedipixI) tailored for digital mammographic applications. These devices are based on semiconductor (Si and GaAs) pixel detectors of different thickness, read-out by custom designed integrated circuits. To assess the imaging capability of such systems, the images of a mammographic phantom have been acquired in standard conditions for a clinical examination. The signal-to-noise ratio (SNR) of details simulating tumor masses has been evaluated. The same phantom has been also radiographed by three different commercial digital mammographic systems in the same reference conditions and a comparison in terms of SNR has been carried out. The spatial resolution of the single photon counting systems has also been evaluated by measuring the line spread function with the edge technique and then calculating the Modulation Transfer Function (MTF). The MTFs of the single photon counting systems have been compared with the MTFs of the commercial systems.

  20. Performances of different digital mammography imaging systems: Evaluation and comparison

    International Nuclear Information System (INIS)

    Bisogni, M.G.; Bulajic, D.; Delogu, P.; Fantacci, M.E.; Novelli, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.

    2005-01-01

    Digital mammography is entering routine clinical use and many commercial systems are now in use in the radiological units for screening and diagnostic mammography. At the same time, the research in the digital mammography field is very active in the development of more and more performing devices. In this paper we present the performance of single photon counting pixel detectors (MedipixI) tailored for digital mammographic applications. These devices are based on semiconductor (Si and GaAs) pixel detectors of different thickness, read-out by custom designed integrated circuits. To assess the imaging capability of such systems, the images of a mammographic phantom have been acquired in standard conditions for a clinical examination. The signal-to-noise ratio (SNR) of details simulating tumor masses has been evaluated. The same phantom has been also radiographed by three different commercial digital mammographic systems in the same reference conditions and a comparison in terms of SNR has been carried out. The spatial resolution of the single photon counting systems has also been evaluated by measuring the line spread function with the edge technique and then calculating the Modulation Transfer Function (MTF). The MTFs of the single photon counting systems have been compared with the MTFs of the commercial systems

  1. A high-performance digital control system for TCV

    International Nuclear Information System (INIS)

    Lister, J.B.; Dutch, M.J.; Milne, P.G.; Means, R.W.

    1997-10-01

    The TCV hybrid analogue-digital plasma control system has been superseded by a high performance Digital Plasma Control System, DPCS, made possible by recent advances in off the shelf technology. We discuss the basic requirements for such a control system and present the design and specifications which were laid down. The nominal and final performances are presented and the complete design is given in detail. The integration of the new system into the current operation of the TCV tokamak is described. The procurement of this system has required close collaboration between the end-users and two commercial suppliers with one of the latter taking full responsibility for the system integration. The impact of this approach on the design and commissioning costs for the TCV project is presented. New possibilities offered by this new system are discussed, including possible work relevant to ITER plasma control development. (author) 3 figs., 5 refs

  2. A high-performance digital control system for TCV

    Energy Technology Data Exchange (ETDEWEB)

    Lister, J.B.; Dutch, M.J. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP); Milne, P.G. [Pentland System Ltd., Livingstone (United Kingdom); Means, R.W. [HNC Software Inc., San Diego, CA (United States)

    1997-10-01

    The TCV hybrid analogue-digital plasma control system has been superseded by a high performance Digital Plasma Control System, DPCS, made possible by recent advances in off the shelf technology. We discuss the basic requirements for such a control system and present the design and specifications which were laid down. The nominal and final performances are presented and the complete design is given in detail. The integration of the new system into the current operation of the TCV tokamak is described. The procurement of this system has required close collaboration between the end-users and two commercial suppliers with one of the latter taking full responsibility for the system integration. The impact of this approach on the design and commissioning costs for the TCV project is presented. New possibilities offered by this new system are discussed, including possible work relevant to ITER plasma control development. (author) 3 figs., 5 refs.

  3. New modified map for digital image encryption and its performance

    Science.gov (United States)

    Suryadi, MT; Yus Trinity Irsan, Maria; Satria, Yudi

    2017-10-01

    Protection to classified digital data becomes so important in avoiding data manipulation and alteration. The focus of this paper is in data and information protection of digital images form. Protection is provided in the form of encrypted digital image. The encryption process uses a new map, {x}n+1=\\frac{rλ {x}n}{1+λ {(1-{x}n)}2}\\quad ({mod} 1), which is called MS map. This paper will show: the results of digital image encryption using MS map and how the performance is regarding the average time needed for encryption/decryption process; randomness of key stream sequence with NIST test, histogram analysis and goodness of fit test, quality of the decrypted image by PSNR, initial value sensitivity level, and key space. The results show that the average time of the encryption process is relatively same as the decryption process and it depends to types and sizes of the image. Cipherimage (encrypted image) is uniformly distributed since: it passes the goodness of fit test and also the histogram of the cipherimage is flat; key stream, that are generated by MS map, passes frequency (monobit) test, and runs test, which means the key stream is a random sequence; the decrypted image has same quality as the original image; and initial value sensitivity reaches 10-17, and key space reaches 3.24 × 10634. So, that encryption algorithm generated by MS map is more resistant to brute-force attack and known plaintext attack.

  4. Practical applications and methods in performing cardiac digital subtraction angiography

    International Nuclear Information System (INIS)

    Markovic, D.M.; Withrow, S.; Moodie, D.S.

    1986-01-01

    One of the purposes of this book is to outline the utility of digital subtraction angiography (DSA) in common clinical practice. No text has dealt with the actual physical setup of the room or the patient prior and during a digital subtraction angiographic study at rest and with exercise. This chapter outlines the steps commonly used when cardiac DSA is performed on patients in the authors' laboratory. The authors have learned over the last few years the best way to prepare the patient and the equipment and it is hoped that utilizing this experience, other centers may avoid the mistakes the authors have made in the past and develop new techniques for the future

  5. Advanced digital technology - improving nuclear power plant performance through maintainability

    International Nuclear Information System (INIS)

    Ford, J.L.; Senechal, R.R.; Altenhein, G.D.; Harvey, R.P.

    1998-01-01

    In today's energy sector there is ever increasing pressure on utilities to operate power plants at high capacity factors. To ensure nuclear power is competitive into the next century, it is imperative that strategic design improvements be made to enhance the performance of nuclear power plants. There are a number of factors that affect a nuclear power plant's performance; lifetime maintenance is one of the major contributors. The maturing of digital technology has afforded ABB the opportunity to make significant design improvements in the area of maintainability. In keeping with ABB's evolutionary advanced nuclear plant design approach, digital technology has systematically been incorporated into the control and protection systems of the most recent Korean nuclear units in operation and under construction. One example of this was the multi-functional design team approach that was utilized for the development of ABB's Digital Plant Protection System (DPPS). The design team consisted of engineers, maintenance technicians, procurement specialists and manufacturing personnel in order to provide a complete perspective on all facets of the design. The governing design goals of increased reliability and safety, simplicity of design, use of off-the-shelf products and reduced need for periodic surveillance testing were met with the selection of proven ABB-Advant Programmable Logic Controllers (PLCs) as the heart of the DPPS. The application of digital PLC technology allows operation for extended periods without requiring routine maintenance or re-calibration. A well documented commercial dedication program approved by the United States Nuclear Regulatory Commission (US NRC) as part of the System 80+ TM Advanced Light Water Reactor Design Certification Program, allowed the use of off-the shelf products in the design of the safety protection system. In addition, a number of mechanical and electrical improvements were made which support maintainability. The result is a DPPS

  6. El cuerpo-huella en el performance digital 10 minutos

    Directory of Open Access Journals (Sweden)

    Daniel Enrique Ariza Gómez, PhD

    2017-01-01

    Full Text Available Este artículo de reflexión aborda el concepto de cuerpo-huella, eje principal del performance “El fajadito”. Esta puesta en escena forma parte de una creación escénica más grande llamada 10 minutos, performance digital que pone en tensión la relación cuerpo-máquina en el entorno de una unidad de cuidados intensivos (UCI, y se entrelaza junto con otros tres para ofrecer al público la totalidad de una obra que surge del proceso de investigación-creación 10 minutos. El discurso del presente artículo se abrirá hacia la comprensión de la manera en que fue abordado, para el performance “El fajadito”, el cuerpo de las personas víctimas de minas antipersona en Colombia. Un cuerpo-huella que aparece en la puesta en escena como un cuerpo en suspensión proponiendo con ello una postura política y social sobre lo que ha significado, para Colombia, el uso de armas que no buscan la muerte del individuo, sino la provocación del dolor y exhibe un cuerpo mutilado como huella de guerra. Palabras clave: fajaditos, cuerpo-huella, 10 minutos, performance digital, minas antipersona.

  7. Baseline Screening Mammography: Performance of Full-Field Digital Mammography Versus Digital Breast Tomosynthesis.

    Science.gov (United States)

    McDonald, Elizabeth S; McCarthy, Anne Marie; Akhtar, Amana L; Synnestvedt, Marie B; Schnall, Mitchell; Conant, Emily F

    2015-11-01

    Baseline mammography studies have significantly higher recall rates than mammography studies with available comparison examinations. Digital breast tomosynthesis reduces recalls when compared with digital mammographic screening alone, but many sites operate in a hybrid environment. To maximize the effect of screening digital breast tomosynthesis with limited resources, choosing which patient populations will benefit most is critical. This study evaluates digital breast tomosynthesis in the baseline screening population. Outcomes were compared for 10,728 women who underwent digital mammography screening, including 1204 (11.2%) baseline studies, and 15,571 women who underwent digital breast tomosynthesis screening, including 1859 (11.9%) baseline studies. Recall rates, cancer detection rates, and positive predictive values were calculated. Logistic regression estimated the odds ratios of recall for digital mammography versus digital breast tomosynthesis for patients undergoing baseline screening and previously screened patients, adjusted for age, race, and breast density. In the baseline subgroup, recall rates for digital mammography and digital breast tomosynthesis screening were 20.5% and 16.0%, respectively (p = 0.002); digital breast tomosynthesis screening in the baseline subgroup resulted in a 22% reduction in recall compared with digital mammography, or 45 fewer patients recalled per 1000 patients screened. Digital breast tomosynthesis screening in the previously screened patients resulted in recall reduction of 14.3% (p tomosynthesis than from digital mammography alone.

  8. El cuerpo-huella en el performance digital 10 minutos

    OpenAIRE

    Daniel Enrique Ariza Gómez, PhD

    2017-01-01

    Este artículo de reflexión aborda el concepto de cuerpo-huella, eje principal del performance “El fajadito”. Esta puesta en escena forma parte de una creación escénica más grande llamada 10 minutos, performance digital que pone en tensión la relación cuerpo-máquina en el entorno de una unidad de cuidados intensivos (UCI), y se entrelaza junto con otros tres para ofrecer al público la totalidad de una obra que surge del proceso de investigación-creación 10 minutos. El discurso del presente art...

  9. Influence of discretization method on the digital control system performance

    Directory of Open Access Journals (Sweden)

    Futás József

    2003-12-01

    Full Text Available The design of control system can be divided into two steps. First the process or plant have to be convert into mathematical model form, so that its behavior can be analyzed. Then an appropriate controller have to be design in order to get the desired response of the controlled system. In the continuous time domain the system is represented by differential equations. Replacing a continuous system into discrete time form is always an approximation of the continuous system. The different discretization methods give different digital controller performance. The methods presented on the paper are Step Invariant or Zero Order Hold (ZOH Method, Matched Pole-Zero Method, Backward difference Method and Bilinear transformation. The above mentioned discretization methods are used in developing PI position controller of a dc motor. The motor model was converted by the ZOH method. The performances of the different methods are compared and the results are presented.

  10. Supply Responses to Digital Distribution: Recorded Music and Live Performances

    OpenAIRE

    Julie Holland Mortimer; Chris Nosko; Alan Sorensen

    2010-01-01

    Changes in technologies for reproducing and redistributing digital goods (e.g., music, movies, software, books) have dramatically affected profitability of these goods, and raised concerns for future development of socially valuable digital products. However, broader illegitimate distribution of digital goods may have offsetting demand implications for legitimate sales of complementary non-digital products. We examine the negative impact of file-sharing on recorded music sales and offsetting ...

  11. Digitization

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    what a concept of digital media might add to the understanding of processes of mediatization and what the concept of mediatization might add to the understanding of digital media. It is argued that digital media open an array of new trajectories in human communication, trajectories which were...

  12. Method and apparatus for performing digital intravenous subtraction angiography

    International Nuclear Information System (INIS)

    Stein, J.A.

    1986-01-01

    This invention relates to digital intravenous subtraction angiography (DISA), and more particularly concerns novel apparatus and techniques for providing high resolution angiograms with equipment that coacts with existing standard medical X-ray equipment. A typical medical X-ray generator provides low mA, continuous X-ray exposures illuminating a standard image intensifier producing an image scanned by a conventional television camera to produce a video signal. An analog-to-digital converter digitizes the signal, and adding means adds the digital frame signals together in real time to provide an intermediate digital signal representing the addition of 5 to 20 frames. Digital storage means store the intermediate image signals. Preferably there are two system memories with means for summing a subsequent intermediate image in the second memory while a previously-formed intermediate image is being transferred to disk storage

  13. Digital passages. Moroccan-Dutch youths performing diaspora, gender and youth cultural identities across digital space

    NARCIS (Netherlands)

    Leurs, K.H.A.|info:eu-repo/dai/nl/343295334

    2012-01-01

    Digital Passages considers how the relations between gender, diaspora and youth culture are digitally articulated by Moroccan-Dutch youths between the age of 12 and 18 years old. Combining new media, gender and postcolonial theory, a transdisciplinary analysis is carried out of a young

  14. Digit Symbol Performance in Mild Dementia and Depression.

    Science.gov (United States)

    Hart, Robert P.; And Others

    1987-01-01

    Patients with mild dementia of the Alzheimer's type (DAT), patients with major depression, and normal control subjects completed the Wechsler Adult Intelligence Scale (WAIS) Digit Symbol test of incidental memory. Though mild DAT and depressed patients had equivalent deficits in psychomotor speed, DAT patients recalled fewer digit-symbol items.…

  15. Performance of digital integrated circuit technologies at very high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Prince, J.L.; Draper, B.L.; Rapp, E.A.; Kromberg, J.N.; Fitch, L.T.

    1980-01-01

    Results of investigations of the performance and reliability of digital bipolar and CMOS integrated circuits over the 25 to 340/sup 0/C range are reported. Included in these results are both parametric variation information and analysis of the functional failure mechanisms. Although most of the work was done using commercially available circuits (TTL and CMOS) and test chips from commercially compatible processes, some results of experimental simulations of dielectrically isolated CMOS are also discussed. It was found that commercial Schottky clamped TTL, and dielectrically isolated, low power Schottky-clamped TTL, functioned to junction temperatures in excess of 325/sup 0/C. Standard gold doped TTL functioned only to 250/sup 0/C, while commercial, isolated I/sup 2/L functioned to the range 250/sup 0/C to 275/sup 0/C. Commercial junction isolated CMOS, buffered and unbuffered, functioned to the range 280/sup 0/C to 310/sup 0/C/sup +/, depending on the manufacturer. Experimental simulations of simple dielectrically isolated CMOS integrated circuits, fabricated with heavier doping levels than normal, functioned to temperatures in excess of 340/sup 0/C. High temperature life testing of experimental, silicone-encapsulated simple TTL and CMOS integrated circuits have shown no obvious life limiting problems to date. No barrier to reliable functionality of TTL bipolar or CMOS integrated ciruits at temperatures in excess of 300/sup 0/C has been found.

  16. Digital marketing strategies, online reviews and hotel performance

    OpenAIRE

    Pelsmacker, De, Patrick; Tilburgh, van, Sophie; Holthof, Christian

    2018-01-01

    Abstract: We investigate to what extent digital marketing strategies (such as having a digital marketing plan, responsiveness to guest reviews, and monitoring and tracking online review information) influence hotel room occupancy and RevPar directly, and indirectly through the mediating effect of the volume and valence of online reviews they lead to, and to what extent this mechanism is different for different types of hotels in terms of star rating and independent versus chain hotels. The re...

  17. High performance 14-bit pipelined redundant signed digit ADC

    International Nuclear Information System (INIS)

    Narula, Swina; Pandey, Sujata

    2016-01-01

    A novel architecture of a pipelined redundant-signed-digit analog to digital converter (RSD-ADC) is presented featuring a high signal to noise ratio (SNR), spurious free dynamic range (SFDR) and signal to noise plus distortion (SNDR) with efficient background correction logic. The proposed ADC architecture shows high accuracy with a high speed circuit and efficient utilization of the hardware. This paper demonstrates the functionality of the digital correction logic of 14-bit pipelined ADC at each 1.5 bit/stage. This prototype of ADC architecture accounts for capacitor mismatch, comparator offset and finite Op-Amp gain error in the MDAC (residue amplification circuit) stages. With the proposed architecture of ADC, SNDR obtained is 85.89 dB, SNR is 85.9 dB and SFDR obtained is 102.8 dB at the sample rate of 100 MHz. This novel architecture of digital correction logic is transparent to the overall system, which is demonstrated by using 14-bit pipelined ADC. After a latency of 14 clocks, digital output will be available at every clock pulse. To describe the circuit behavior of the ADC, VHDL and MATLAB programs are used. The proposed architecture is also capable of reducing the digital hardware. Silicon area is also the complexity of the design. (paper)

  18. Enhancement of Performance and Motivation through Application of Digital Games in an English Language Class

    Science.gov (United States)

    Wichadee, Saovapa; Pattanapichet, Fasawang

    2018-01-01

    The study was conducted to find out what impact a digital game had on students' learning performance and motivation. A quasi-experimental study was performed with two groups of students. The experimental group was taught using the digital game "Kahoot" whereas the control group was taught with the conventional method. Pre-tests,…

  19. The Impact of Digital Skills on Educational Outcomes: Evidence from Performance Tests

    Science.gov (United States)

    Pagani, Laura; Argentin, Gianluca; Gui, Marco; Stanca, Luca

    2016-01-01

    Digital skills are increasingly important for labour market outcomes and social participation. Do they also matter for academic performance? This paper investigates the effects of digital literacy on educational outcomes by merging data from the Italian National Assessment in secondary schools with an original data-set on performance tests of…

  20. Digital mammography screening: average glandular dose and first performance parameters

    International Nuclear Information System (INIS)

    Weigel, S.; Girnus, R.; Czwoydzinski, J.; Heindel, W.; Decker, T.; Spital, S.

    2007-01-01

    Purpose: The Radiation Protection Commission demanded structured implementation of digital mammography screening in Germany. The main requirements were the installation of digital reference centers and separate evaluation of the fully digitized screening units. Digital mammography screening must meet the quality standards of the European guidelines and must be compared to analog screening results. We analyzed early surrogate indicators of effective screening and dosage levels for the first German digital screening unit in a routine setting after the first half of the initial screening round. Materials and Methods: We used three digital mammography screening units (one full-field digital scanner [DR] and two computed radiography systems [CR]). Each system has been proven to fulfill the requirements of the National and European guidelines. The radiation exposure levels, the medical workflow and the histological results were documented in a central electronic screening record. Results: In the first year 11,413 women were screened (participation rate 57.5 %). The parenchymal dosages for the three mammographic X-ray systems, averaged for the different breast sizes, were 0.7 (DR), 1.3 (CR), 1.5 (CR) mGy. 7 % of the screened women needed to undergo further examinations. The total number of screen-detected cancers was 129 (detection rate 1.1 %). 21 % of the carcinomas were classified as ductal carcinomas in situ, 40 % of the invasive carcinomas had a histological size ≤ 10 mm and 61 % < 15 mm. The frequency distribution of pT-categories of screen-detected cancer was as follows: pTis 20.9 %, pT1 61.2 %, pT2 14.7 %, pT3 2.3 %, pT4 0.8 %. 73 % of the invasive carcinomas were node-negative. (orig.)

  1. Performance of a fully disposable, digital, single-operator cholangiopancreatoscope.

    Science.gov (United States)

    Shah, Raj J; Raijman, Isaac; Brauer, Brian; Gumustop, Bora; Pleskow, Douglas K

    2017-07-01

    Background and study aim  Our aim was to evaluate the first use in humans of a new, single-use, digital, single-operator intraductal cholangiopancreatoscopy system (IDCP). Patients and methods  Data were collected retrospectively from four US institutions between February 2015 and April 2015. The visual impression of neoplasia or benign findings with IDCP was determined by the performing endoscopist. High grade dysplasia, intraductal papillary mucinous neoplasm, neuroendocrine tumor, and malignancy were categorized as neoplasia. Benign disease was defined as the absence of neoplasia during ≥ 6 months of follow-up. Results  Patients (n = 108) with indeterminate strictures, dilatation, or difficult stones underwent IDCP. Of 74 patients with indeterminate stricture or dilatation, 29 (39 %) had neoplasia, of which 25 were confirmed by miniature biopsy forceps, 2 by surgical pathology, and 2 by the presence of metastatic disease on follow-up imaging. In patients with benign disease, 15 had concentric stenosis or normal/erythematous changes, 5 had low papillary mucosal projections, 6 had coarse granular mucosa, and 4 had nodular mucosa. Findings in patients with neoplastic disease included dilated, tortuous vessels ("tumor vessels"; n = 13), irregular margins with partial occlusion of the lumen (infiltrative stricture, n = 12), villous or nodular mass (n = 9), and finger-like villiform projections (n = 5). Operating characteristics for indeterminate stricture or dilatation were: 97 % sensitivity, 93 % specificity, 90 % positive predictive value, 98 % negative predictive value. Targeted biopsy yielded 86 % sensitivity and 100 % specificity. Stone clearance was noted in all cases. Adverse events occurred in 3 %. Conclusion  The new IDCP system provides enhanced image resolution, and may improve the ability to target difficult stones and diagnose indeterminate strictures. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Benchmarking the performance of fixed-image receptor digital radiography systems. Part 2: system performance metric.

    Science.gov (United States)

    Lee, Kam L; Bernardo, Michael; Ireland, Timothy A

    2016-06-01

    This is part two of a two-part study in benchmarking system performance of fixed digital radiographic systems. The study compares the system performance of seven fixed digital radiography systems based on quantitative metrics like modulation transfer function (sMTF), normalised noise power spectrum (sNNPS), detective quantum efficiency (sDQE) and entrance surface air kerma (ESAK). It was found that the most efficient image receptors (greatest sDQE) were not necessarily operating at the lowest ESAK. In part one of this study, sMTF is shown to depend on system configuration while sNNPS is shown to be relatively consistent across systems. Systems are ranked on their signal-to-noise ratio efficiency (sDQE) and their ESAK. Systems using the same equipment configuration do not necessarily have the same system performance. This implies radiographic practice at the site will have an impact on the overall system performance. In general, systems are more dose efficient at low dose settings.

  3. DIGITAL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  4. Bounds on the performance of a class of digital communication systems

    Science.gov (United States)

    Polk, D. R.; Gupta, S. C.; Cohn, D. L.

    1973-01-01

    Bounds on the capacity of a class of digital communication channels are derived. Equating the bounds on capacity to rate-distortion functions of (typical) sources in turn produces bounds on the performance of a class of digital communication systems. For ratios of squared quantization level to noise variance much less than one, the power requirements for this class of digital communication systems are shown to be within approximately 3 dB of the theoretical optimum.

  5. Digital Story Creation: Its Impact towards Academic Performance

    Science.gov (United States)

    Ong, Charito G.

    2017-01-01

    When students are engaged in the process of creating a digital story, they synthesize a variety of literacy skills for the authentic product: researching, writing, organizing, presenting, interviewing, problem-solving, assessing, as well as employing interpersonal and technology skills (Baggett, 2007). With all these skills to be developed among…

  6. A performance of reality: handwriting and paper in digital literature

    NARCIS (Netherlands)

    van Dijk, Y.

    2011-01-01

    Digital literature emphasizes its own medium, and it brings to the foreground the graphic, material aspects of language. Experiments with the new medium and with the form of language are generally presented and interpreted within a framework of the historical avant-garde or the neo-avant-garde. This

  7. Performance of a digital PCO2/SPO2 ear sensor.

    Science.gov (United States)

    Kocher, Serge; Rohling, Roman; Tschupp, Andres

    2004-04-01

    For determining the adequacy of ventilation, conventional pulse oximetry should be amended by PaCO2 (= arterial carbon dioxide partial pressure). This study investigates the precision of carbon dioxide measurements of the first digital ear-clip sensor providing continuous non-invasive monitoring of PaCO2, SpO2 (= functional arterial oxygen saturation as estimated with a pulse oximeter) and pulse rate and compares it to two conventional analog oximeters. 30 hypoxemia episodes in 6 adult volunteers were investigated in a standardized protocol. Masimo analog finger sensor, Nellcor analog ear sensor, SenTec digital ear sensor. The difference between PCO2 data (= PaCO2 estimated from the measured PcCO2 based on an algorithm by Severinghaus) (PcCO2 = cutaneous carbon dioxide pressure) and the PaCO2 is clinically unimportant. Therefore, we suggest, the two methods of estimating patient's carbon dioxide status can be used interchangeably. Combined digital SpO2/ PcCO2 ear sensors are very promising to allow for a fast and reliable monitoring of patient's oxygenation, hyper-/hypocapnia and ventilation with one single non-invasive probe. Optimal primary signal processing--amplification and digitalisation within the probe--allow for fast and reliable downstream signal processing algorithms. The resulting short SpO2 response times give the medical staff more time to take appropriate actions.

  8. Digital Filtering Performance in the ATLAS Level-1 Calorimeter Trigger

    CERN Document Server

    Hadley, D R; The ATLAS collaboration

    2010-01-01

    The ATLAS Level-1 Calorimeter Trigger is a hardware-based system designed to identify high-pT jets, elec- tron/photon and tau candidates, and to measure total and missing ET in the ATLAS Liquid Argon and Tile calorimeters. It is a pipelined processor system, with a new set of inputs being evaluated every 25ns. The overall trigger decision has a latency budget of 2µs, including all transmission delays. The calorimeter trigger uses about 7200 reduced granularity analogue signals, which are first digitized at the 40 MHz LHC bunch-crossing frequency, before being passed to a digital Finite Impulse Re- sponse (FIR) filter. Due to latency and chip real-estate constraints, only a simple 5-element filter with limited precision can be used. Nevertheless, this filter achieves a significant reduction in noise, along with improving the bunch-crossing assignment and energy resolution for small signals. The context in which digital filters are used for the ATLAS Level-1 Calorimeter Trigger is presented, before descr...

  9. Digital Filter Performance for the ATLAS Level-1 Calorimeter Trigger

    CERN Document Server

    Hadley, D R; The ATLAS collaboration

    2010-01-01

    The ATLAS Level-1 Calorimeter Trigger is a hardware-based system designed to identify high-pT jets, electron/photon and tau candidates, and to measure total and missing ET in the ATLAS Liquid Argon and Tile calorimeters. It is a pipelined processor system, with a new set of inputs being evaluated every 25ns. The overall trigger decision has a latency budget of 2µs, including all transmission delays. The calorimeter trigger uses about 7200 reduced granularity analogue signals, which are first digitized at the 40 MHz LHC bunch-crossing frequency, before being passed to a digital Finite Impulse Response (FIR) filter. Due to latency and chip real-estate constraints, only a simple 5-element filter with limited precision can be used. Nevertheless this filter achieves a significant reduction in noise, along with improving the bunch-crossing assignment and energy resolution for small signals. The context in which digital filters are used for the ATLAS Level-1 Calorimeter Trigger will be presented, before describing ...

  10. Very High-Performance Advanced Filter Bank Analog-to-Digital Converter (AFB ADC) Project

    National Research Council Canada - National Science Library

    Velazquez, Scott

    1999-01-01

    ... of the art by using a parallel array of individual commercial off the shelf converters. The significant performance improvements afforded by the Advanced Filter Bank Analog to Digital Converter (AFB ADC...

  11. Effects of Simulated Conductive Hearing Loss on Dichotic Listening Performance for Digits.

    Science.gov (United States)

    Niccum, Nancy; And Others

    1987-01-01

    Conductive hearing losses were simulated in 12 subjects aged 19-35 and performance was compared with normal hearing performance. Digit dichotic performance was affected when test intensities were within 8 dB of the "knees" (95 percent correct point) of monotic performance intensity functions, but not when test intensities were 12 dB…

  12. Experimental Adaptive Digital Performance Monitoring for Optical DP-QPSK Coherent Receiver

    DEFF Research Database (Denmark)

    Borkowski, Robert; Zhang, Xu; Zibar, Darko

    2011-01-01

    We report on a successful experimental demonstration of a digital optical performance monitoring (OPM) yielding satisfactory estimation accuracy along with adaptive impairment equalization. No observable penalty is measured when equalizer is driven by monitoring module.......We report on a successful experimental demonstration of a digital optical performance monitoring (OPM) yielding satisfactory estimation accuracy along with adaptive impairment equalization. No observable penalty is measured when equalizer is driven by monitoring module....

  13. The test and control system for high performance digital power supplies of SSRF

    International Nuclear Information System (INIS)

    Tang Junlong; Li Deming; Shen Tianjian

    2009-01-01

    A test and control system was designed to evaluate performance of the digital power supplies for SSRF. The software of serial communication (RS-232) and Ethernet interface was developed with Lab VIEW. The system can perform functions of instrument and power supply control, data acquisition and display, and store data for 24 h. LAN users can access the system and acquire data conveniently. The data are stored in Excel for analysis and establishment of database of digital PS in the future. (authors)

  14. JMorph: Software for performing rapid morphometric measurements on digital images of fossil assemblages

    Science.gov (United States)

    Lelièvre, Peter G.; Grey, Melissa

    2017-08-01

    Quantitative morphometric analyses of form are widely used in palaeontology, especially for taxonomic and evolutionary research. These analyses can involve several measurements performed on hundreds or even thousands of samples. Performing measurements of size and shape on large assemblages of macro- or microfossil samples is generally infeasible or impossible with traditional instruments such as vernier calipers. Instead, digital image processing software is required to perform measurements via suitable digital images of samples. Many software packages exist for morphometric analyses but there is not much available for the integral stage of data collection, particularly for the measurement of the outlines of samples. Some software exists to automatically detect the outline of a fossil sample from a digital image. However, automatic outline detection methods may perform inadequately when samples have incomplete outlines or images contain poor contrast between the sample and staging background. Hence, a manual digitization approach may be the only option. We are not aware of any software packages that are designed specifically for efficient digital measurement of fossil assemblages with numerous samples, especially for the purposes of manual outline analysis. Throughout several previous studies, we have developed a new software tool, JMorph, that is custom-built for that task. JMorph provides the means to perform many different types of measurements, which we describe in this manuscript. We focus on JMorph's ability to rapidly and accurately digitize the outlines of fossils. JMorph is freely available from the authors.

  15. Operational performance of a bunch by bunch digital damper in the Fermilab Main Injector

    International Nuclear Information System (INIS)

    Adamson, P.; Ashmanskas, W.J.; Foster, G.W.; Hansen, S.; Marchionni, A.; Nicklaus, D.; Semenov, A.; Wildman, D.; Kang, H.

    2005-01-01

    We have implemented a transverse and longitudinal bunch by bunch digital damper system in the Fermilab Main Injector, using a single digital board for all 3 coordinates. The system has been commissioned over the last year, and is now operational in all MI cycles, damping beam bunched at both 53MHz and 2.5MHz. We describe the performance of this system both for collider operations and high-intensity running for the NuMI project

  16. “Do We Have LIFT-Off?” Social Media Marketing and Digital Performance at a British Arts Festival

    OpenAIRE

    Miles, S

    2017-01-01

    Arts festivals have been explored through many lenses, but social media marketing and digital performance are less studied. The potential of social media networks in digital performance is exemplified by the London International Festival of Theatre (LIFT), which repositions social media technology as an enabler for audiences to co-produce digitally oriented performance. This article argues that the relationship between social media marketing and performance is more hybridized than often assum...

  17. The Use of Digital Repositories for Enhancing Teacher Pedagogical Performance

    Science.gov (United States)

    Cohen, Anat; Kalimi, Sharon; Nachmias, Rafi

    2013-01-01

    This research examines the usage of local learning material repositories at school, as well as related teachers' attitudes and training. The study investigates the use of these repositories for enhancing teacher performance and assesses whether the assimilation of the local repositories increases their usage of and contribution to by teachers. One…

  18. Noise Performance Evaluation of the Candidate Digitizers for the MAJORANA DEMONSTRATOR

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Navarrete, Estanislao

    2011-03-16

    The noise performance evaluation of the two digitizer cards being considered for the MAJORANA DEMONSTRATOR (MJD) is presented in this document. The procurement of the data acquisition electronics for the MJD is scheduled to happen this year. At the time of writing this document, there are two candidate digitizer electronic boards. One aspect that is being considered by the collaboration is the feasibility of using the MJD for dark matter searches. The feasibility of using the MJD for this application is going to be dictated by the ability of the demonstrator to reach sub-keV energy resolution. One of the potential sources of noise in the MJD is the data acquisition system. This document will is concluded with a recommendation for the final digitizer board by comparing the noise performance of the two electronics systems. Noise parameters such as the effective number of bits, input range linearity and signal to noise ratio are experimentally determined. The two digitizer cards feature different on-board digital signal processing and these features are compared. The experimental set-up was also used to identify sources of noise. This paper describes these sources of noise in the data acquisition system, along with mitigation strategies. Issues such as grounding and wiring scheme have an impact in the overall data acquisition system performance and are discussed in detail. As a conclusion, the suitability of each one of the cards to become the back bone of the data acquisition system of the MJD is discussed.

  19. Human Computer Confluence in Rehabilitation: Digital Media Plasticity and Human Performance Plasticity

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2013-01-01

    Digital media plasticity evocative to embodied interaction is presented as a utilitarian tool when mixed and matched to target human performance potentials specific to nuance of development for those with impairment. A distinct intervention strategy trains via alternative channeling of external s...

  20. The digital era: the position and interests of creators and performers

    NARCIS (Netherlands)

    Akker, I.; Poort, J.; Rutten, P.; Weda, J.

    2011-01-01

    This contribution presents the results of a survey held among creators and performers in media, arts and entertainment in The Netherlands. It concerns the future of copyright in the digital age and its implications for the creative professions as perceived by those working in it. Based on cluster

  1. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; van der Meij, Hans; Leemkuil, Hendrik H.; McKenney, Susan

    2015-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  2. Performance Evaluation of Digital Coherent Receivers for Phase-Modulated Radio-Over-Fiber Links

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Tafur Monroy, Idelfonso

    2011-01-01

    The performance of optical phase-modulated (PM) radio-over-fiber (RoF) links assisted with coherent detection and digital signal processing (PM-Coh) is analyzed and experimentally demonstrated for next-generation wireless-over-fiber systems. PM-Coh offers high linearity for transparent transport ...

  3. Visual and auditory digit-span performance in native and nonnative speakers

    NARCIS (Netherlands)

    Olsthoorn, N.M.; Andringa, S.; Hulstijn, J.H.

    2014-01-01

    We compared 121 native and 114 non-native speakers of Dutch (with 35 different first languages) on four digit-span tasks, varying modality (visual/auditory) and direction (forward/backward). An interaction was observed between nativeness and modality, such that, while natives performed better than

  4. Examining Unusual Digit Span Performance in a Population of Postsecondary Students Assessed for Academic Difficulties

    Science.gov (United States)

    Harrison, Allyson G.; Rosenblum, Yoni; Currie, Shannon

    2010-01-01

    Methods of identifying poor test-related motivation using the Wechsler Adult Intelligence Scale Digit Span subtest are based on identification of performance patterns that are implausible if the test taker is investing full effort. No studies to date, however, have examined the specificity of such measures, particularly when evaluating persons…

  5. In search of design principles for developing digital learning & performance support for a student design task

    NARCIS (Netherlands)

    Bollen, Lars; Van der Meij, Hans; Leemkuil, Henny; McKenney, Susan

    2016-01-01

    A digital learning and performance support environment for university student design tasks was developed. This paper describes on the design rationale, process, and the usage results to arrive at a core set of design principles for the construction of such an environment. We present a collection of

  6. Digital Devices, Distraction, and Student Performance: Does In-Class Cell Phone Use Reduce Learning?

    Science.gov (United States)

    Duncan, Douglas K.; Hoekstra, Angel R.; Wilcox, Bethany R.

    2012-01-01

    The recent increase in use of digital devices such as laptop computers, iPads, and web-enabled cell phones has generated concern about how technologies affect student performance. Combining observation, survey, and interview data, this research assesses the effects of technology use on student attitudes and learning. Data were gathered in eight…

  7. Digital Game-Based Learning Supports Student Motivation, Cognitive Success, and Performance Outcomes

    Science.gov (United States)

    Woo, Jeng-Chung

    2014-01-01

    Traditional multimedia learning is primarily based on the cognitive load concept of information processing theory. Recent digital game-based learning (DGBL) studies have focused on exploring content support for learning motivation and related game characteristics. Motivation, volition, and performance (MVP) theory indicates that cognitive load and…

  8. Relation between Academic Performance and Students' Engagement in Digital Learning Activities

    Science.gov (United States)

    Bertheussen, Bernt Arne; Myrland, Øystein

    2016-01-01

    This study reports on the effect of student engagement in digital learning activities on academic performance for 120 students enrolled in an undergraduate finance course. Interactive practice and exam problem files were available to each student, and individual download activity was automatically recorded during the first 50 days of the course.…

  9. The Role of Online Reader Experience in Explaining Students' Performance in Digital Reading

    Science.gov (United States)

    Gil-Flores, Javier; Torres-Gordillo, Juan-Jesus; Perera-Rodriguez, Victor-Hugo

    2012-01-01

    This study explores the relationship between students' extracurricular experiences online and their performance on the Program for International Student Assessment (PISA), focusing specifically on students' competence in digital reading. The study uses a descriptive, correlational, ex post facto design. The data are taken from Spanish students'…

  10. Proposal of an innovative benchmark for comparison of the performance of contactless digitizers

    Science.gov (United States)

    Iuliano, Luca; Minetola, Paolo; Salmi, Alessandro

    2010-10-01

    Thanks to the improving performances of 3D optical scanners, in terms of accuracy and repeatability, reverse engineering applications have extended from CAD model design or reconstruction to quality control. Today, contactless digitizing devices constitute a good alternative to coordinate measuring machines (CMMs) for the inspection of certain parts. The German guideline VDI/VDE 2634 is the only reference to evaluate whether 3D optical measuring systems comply with the declared or required performance specifications. Nevertheless it is difficult to compare the performance of different scanners referring to such a guideline. An adequate novel benchmark is proposed in this paper: focusing on the inspection of production tools (moulds), the innovative test piece was designed using common geometries and free-form surfaces. The reference part is intended to be employed for the evaluation of the performance of several contactless digitizing devices in computer-aided inspection, considering dimensional and geometrical tolerances as well as other quantitative and qualitative criteria.

  11. Proposal of an innovative benchmark for comparison of the performance of contactless digitizers

    International Nuclear Information System (INIS)

    Iuliano, Luca; Minetola, Paolo; Salmi, Alessandro

    2010-01-01

    Thanks to the improving performances of 3D optical scanners, in terms of accuracy and repeatability, reverse engineering applications have extended from CAD model design or reconstruction to quality control. Today, contactless digitizing devices constitute a good alternative to coordinate measuring machines (CMMs) for the inspection of certain parts. The German guideline VDI/VDE 2634 is the only reference to evaluate whether 3D optical measuring systems comply with the declared or required performance specifications. Nevertheless it is difficult to compare the performance of different scanners referring to such a guideline. An adequate novel benchmark is proposed in this paper: focusing on the inspection of production tools (moulds), the innovative test piece was designed using common geometries and free-form surfaces. The reference part is intended to be employed for the evaluation of the performance of several contactless digitizing devices in computer-aided inspection, considering dimensional and geometrical tolerances as well as other quantitative and qualitative criteria

  12. Catalyzing healthcare transformation with digital health: Performance indicators and lessons learned from a Digital Health Innovation Group.

    Science.gov (United States)

    Tseng, Jocelyn; Samagh, Sonia; Fraser, Donna; Landman, Adam B

    2018-06-01

    Despite considerable investment in digital health (DH) companies and a growing DH ecosystem, there are multiple challenges to testing and implementing innovative solutions. Health systems have recognized the potential of DH and have formed DH innovation centers. However, limited information is available on DH innovation center processes, best practices, or outcomes. This case report describes a DH innovation center process that can be replicated across health systems and defines and benchmarks process indicators to assess DH innovation center performance. The Brigham and Women's Hospital's Digital Health Innovation Group (DHIG) accelerates DH innovations from idea to pilot safely and efficiently using a structured process. Fifty-four DH innovations were accelerated by the DHIG process between July 2014 and December 2016. In order to measure effectiveness of the DHIG process, key process indicators were defined as 1) number of solutions that completed each DHIG phase and 2) length of time to complete each phase. Twenty-three DH innovations progressed to pilot stage and 13 innovations were terminated after barriers to pilot implementation were identified by the DHIG process. For 4 DH solutions that executed a pilot, the average time for innovations to proceed from DHIG intake to pilot initiation was 9 months. Overall, the DHIG is a reproducible process that addresses key roadblocks in DH innovation within health systems. To our knowledge, this is the first report to describe DH innovation process indicators and results within an academic health system. Therefore, there is no published data to compare our results with the results of other DH innovation centers. Standardized data collection and indicator reporting could allow benchmark comparisons across institutions. Additional opportunities exist for the validation of DH solution effectiveness and for translational support from pilot to implementation. These are critical steps to advance DH technologies and

  13. Performance study of Philips digital silicon photomultiplier coupled to scintillating crystals

    International Nuclear Information System (INIS)

    Liu, Z.; Pizzichemi, M.; Paganoni, M.; Auffray, E.; Lecoq, P.

    2016-01-01

    Silicon photomultipliers (SiPMs) and scintillators are often arranged in the shape of arrays in Positron Emission Tomography (PET) systems. Digital SiPMs provide signal readout in single photon avalanche diode (SPAD) level. From the photon count rate measurement of each SPAD cell of digital SiPM, we found that the output scintillating photons distribute in an area larger than the scintillator physical coupling area. Taking advantage of the possibility to enable/disable individual cells of the digital SiPM, a group of Lutetium-yttrium oxyorthosilicate (LYSO) crystals with different dimensions coupled to a digital SiPM was used to study the influence of using different SiPM active area on the number of photons detected, energy resolution and coincidence time resolution (CTR). For the same crystal coupled to the digital SiPM, the larger the active area of digital SiPM, the higher the number of photons detected. The larger active area of the digital SiPM also results in a better energy resolution after saturation correction. The best energy resolution full width half maximum (FWHM) obtained for the 2×2×5mm 3 , 2×2×10 mm 3 , 2×2×15mm 3 , 2×2×20mm 3 LYSO crystals was 10.7%, 11.6%, 12.1%, 12.5%, respectively. For crystals with different cross sections coupled to the digital SiPM, we found that the larger the cross section of coupling area, the more photons were detected and thus a better energy resolution was obtained. The CTR of crystals fully wrapped with Teflon or without wrapping was measured by positioning two identical crystals facing each other. A larger area of digital SiPM improves the CTR and the CTR reaches the plateau when the active area is larger than 2.2×2.2mm 2 with both two configurations of wrapping. The best CTR value for the 2×2×5mm 3 , 2×2×10mm 3 , 2×2×15mm 3 , 2×2×20mm 3 LYSO crystals was 128.9 ps, 148.4 ps, 171.6 ps, 177.9 ps, respectively. The measurements performed lead us to conclude that optimising the coupling between crystal

  14. Impact of matrix size on observer performance in digital chest radiography

    International Nuclear Information System (INIS)

    Koelblinger, C.

    2003-02-01

    This thesis compared the observer performance in the detection of abnormalities on 2k matrix(0,2 mm pixel size) and 4k matrix (0,1 mm pixel size) digital chest radiographs. Eighty five patients who underwent CT of the thorax were prospectively reccruited into the study. A chest x-ray of each patient was acquired in 2k and 4k format and four readers analyzed the images by different criterias. On the one hand a ROC analysis was performed with the CT data as goldstandard. On the other hand each reader had to rate different anatomical structures in a direct comparison of the pictures. The results of the ratings did not show any significant difference between the 2k and the 4k format. The conclusion or this study is that the use of a 4k instead of a 2k matrix in digital chest radiography does not yield to an improved observer performance. (author)

  15. Performance Effects of Display Incogruity in a Digital and Analog Clock Reading Task

    Science.gov (United States)

    Comstock, J. Raymond, Jr.; Derks, Peter L.

    2004-01-01

    In an era of increasing automation, it is important to design displays and input devices that minimize human error. In this context, information concerning the human response to the detection of incongruous information is important. Such incongruous information can be operationalized as unexpected (perhaps erroneous) information on which a decision by the human or operation by an automated system is based. In the aviation environment, decision making when faced with inadequate, incomplete, or incongruous information may occur in a failure scenario. An additional challenge facing the human operator in automated environments is maintaining alertness or vigilance. The vigilance issue is of particular concern as a factor that may interact with performance when faced with inadequate, incomplete, or incongruous information. From the literature on eye-scan behavior we know that the time spent looking at a particular display or indicator is a function of the type of information one is trying to discern from the display. For example, quick glances are all it takes for confirming that an indicator is in a normal position or range, whereas a continuous look of several seconds may be required for confirmation that a complex control input is having the desired effect. Important to consider is that while an extended look takes place, visual input from other sources may be missed. Much like an extended look, the interpretation of incongruous information may require extra time. The present experiment was designed to explore the performance consequences of a decision making task when incongruous information was presented. For this experiment a display incongruity was created on a subset of trials of a clock reading laboratory task. Display incongruity was made possible through presentation of 'impossible' times (e.g. 1:65 or 11:90). Subjects made 'same' 'different' decisions and keyboard responses to pairings of Analog-Analog (AA), Digital-Digital (DD), and Analog- Digital (AD

  16. Exploration of a digital audio processing platform using a compositional system level performance estimation framework

    DEFF Research Database (Denmark)

    Tranberg-Hansen, Anders Sejer; Madsen, Jan

    2009-01-01

    This paper presents the application of a compositional simulation based system-level performance estimation framework on a non-trivial industrial case study. The case study is provided by the Danish company Bang & Olufsen ICEpower a/s and focuses on the exploration of a digital mobile audio...... processing platform. A short overview of the compositional performance estimation framework used is given followed by a presentation of how it is used for performance estimation using an iterative refinement process towards the final implementation. Finally, an evaluation in terms of accuracy and speed...

  17. Performance characteristics of digital vs film screen mammography in community practice.

    Science.gov (United States)

    Dabbous, Firas; Dolecek, Therese A; Friedewald, Sarah M; Tossas-Milligan, Katherine Y; Macarol, Tere; Summerfelt, Wm Thomas; Rauscher, Garth H

    2018-05-01

    We compared the performance characteristics of 297 629 full field digital (FFDM) and 416 791 screen film mammograms (SFM). Sensitivity increased with age, decreased with breast density, and was lower for more aggressive and lobular tumors. While sensitivity did not differ significantly by modality, specificity was generally 1%-2% points higher for FFDM than for SFM across age and breast density categories. The lower recall rate for FFDM vs SFM in our study may partially explain performance differences by modality. In this large health care organization, modest gains in performance were achieved with the introduction of FFDM as a replacement for SFM. © 2017 Wiley Periodicals, Inc.

  18. The Use of Digital Radiography in the Evaluation of Radioactive Materials. Packaging Performance Testing

    International Nuclear Information System (INIS)

    May, C; Lawrence Gelder, L; Boyd Howard, B

    2007-01-01

    New designs of radioactive material shipping packages are required to be evaluated in accordance with 10 CFR Part 71, ''Packaging and Transportation of Radioactive Material''. This paper will discuss the use of digital radiography to evaluate the effects of the tests required by 10 CFR 71.71, Normal Conditions of Transport (NCT), and 10 CFR 71.73, Hypothetical Accident Conditions (HAC). One acceptable means of evaluating packaging performance is to subject packagings to the series of NCT and HAC tests. The evaluation includes a determination of the effect on the packaging by the conditions and tests. That determination has required that packagings be cut and sectioned to learn the actual effects on internal components. Digital radiography permits the examination of internal packaging components without sectioning a package. This allows a single package to be subjected to a series of tests. After each test, the package is digitally radiographed and the effects of particular tests evaluated. Radiography reduces the number of packages required for testing and also reduces labor and materials required to section and evaluate numerous packages. This paper will include a description of the digital radiography equipment used in the testing and evaluation of the 9977 and 9978 packages at SRNL. The equipment is capable of making a single radiograph of a full-sized package in one exposure. Radiographs will be compared to sectioned packages that show actual conditions compared to radiographic images

  19. SEU tests performed on the digital communication system for LHC cryogenic instrumentation

    International Nuclear Information System (INIS)

    Casas-Cubillos, J.; Faccio, F.; Gomes, P.; Martin, M.A.; Rodriguez-Ruiz, M.A.

    2002-01-01

    The future LHC particle accelerator will use a large number of cryogenic sensors and actuators, most of which are located inside the machine tunnel and therefore in a radiation environment. These elements will communicate through a fieldbus. This paper reports the irradiation study carried out on WorldFIP fieldbus communication system. A digital communication system based on WorldFIP fieldbus protocol has been implemented and single event effects and total ionizing dose radiation tests have been performed on it

  20. An experimental investigation on relationship between PSFs and operator performances in the digital main control room

    International Nuclear Information System (INIS)

    Park, Jooyoung; Lee, Daeil; Jung, Wondea; Kim, Jonghyun

    2017-01-01

    Highlights: • The relationship between performance shaping factors and operator performances are experimentally investigated. • The experiment includes features of digital main control room. • The result indicates that the operator’s experience level is the most effective on the performance. - Abstract: This study designs an experiment to investigate the relationship between performance shaping factors (PSFs) and operator performances. This study involves selecting three PSFs that are controllable in the experiments: (1) experience, (2) complexity, and (3) urgency. Six scenarios are developed to reflect the PSFs. The experiment involves the participation of licensed operators and the use of an APR1400 simulator. During the experiment, operator performances, such as completion time, error, secondary task, workload, and situation awareness, are measured and collected. The experimental result indicates that the operator’s experience is most effective on the overall performances. The task complexity influences the secondary tasks and situation awareness.

  1. Stability and performance analysis of a jump linear control system subject to digital upsets

    Science.gov (United States)

    Wang, Rui; Sun, Hui; Ma, Zhen-Yang

    2015-04-01

    This paper focuses on the methodology analysis for the stability and the corresponding tracking performance of a closed-loop digital jump linear control system with a stochastic switching signal. The method is applied to a flight control system. A distributed recoverable platform is implemented on the flight control system and subject to independent digital upsets. The upset processes are used to stimulate electromagnetic environments. Specifically, the paper presents the scenarios that the upset process is directly injected into the distributed flight control system, which is modeled by independent Markov upset processes and independent and identically distributed (IID) processes. A theoretical performance analysis and simulation modelling are both presented in detail for a more complete independent digital upset injection. The specific examples are proposed to verify the methodology of tracking performance analysis. The general analyses for different configurations are also proposed. Comparisons among different configurations are conducted to demonstrate the availability and the characteristics of the design. Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 61403395), the Natural Science Foundation of Tianjin, China (Grant No. 13JCYBJC39000), the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry, China, the Tianjin Key Laboratory of Civil Aircraft Airworthiness and Maintenance in Civil Aviation of China (Grant No. 104003020106), and the Fund for Scholars of Civil Aviation University of China (Grant No. 2012QD21x).

  2. Use of prior mammograms in the transition to digital mammography: A performance and cost analysis

    International Nuclear Information System (INIS)

    Taylor-Phillips, S.; Wallis, M.G.; Duncan, A.; Gale, A.G.

    2012-01-01

    Breast screening in Europe is gradually changing from film to digital imaging and reporting of cases. In the transition period prior mammograms (from the preceding screening round) are films thereby potentially causing difficulties in comparison to current digital mammograms. To examine this breast screening performance was measured at a digital mammography workstation with prior mammograms displayed in different formats, and the associated costs calculated. 160 selected difficult cases (41% malignant) were read by eight UK qualified mammography readers in three conditions: with film prior mammograms; with digitised prior mammograms; or without prior mammograms. Lesion location and probability of malignancy were recorded, alongside a decision of whether to recall each case for further tests. JAFROC analysis showed a difference between conditions (p = .006); performance with prior mammograms in either film or digitised formats was superior to that without prior mammograms (p < .05). There was no difference in the performance when the prior mammograms were presented in film or digitised form. The number of benign or normal cases recalled was 26% higher without prior mammograms than with digitised or film prior mammograms (p < .05). This would correspond to an increase in recall rate at the study hospital from 4.3% to 5.5% with no associated increase in cancer detection rate. The cost of this increase was estimated to be £11,581 (€13,666) per 10,000 women screened, which is higher than the cost of digitised (£11,114/€13,115), or film display (£6451/€7612) of the prior mammograms. It is recommended that, where available, prior mammograms are used in the transition to digital breast screening.

  3. 37 CFR 382.2 - Royalty fees for the digital performance of sound recordings and the making of ephemeral...

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Royalty fees for the digital... SATELLITE DIGITAL AUDIO RADIO SERVICES Preexisting Subscription Services § 382.2 Royalty fees for the... monthly royalty fee for the public performance of sound recordings pursuant to 17 U.S.C. 114(d)(2) and the...

  4. Digital Game Playing Motives among Adolescents: Relations to Parent-Child Communication, School Performance, Sleeping Habits, and Perceived Health

    Science.gov (United States)

    Wallenius, Marjut; Rimpela, Arja; Punamaki, Raija-Leena; Lintonen, Tomi

    2008-01-01

    The aims of this research were to describe Finnish adolescents' different motives for digital game playing, and to examine relations between digital game playing and parent-child communication, school performance, sleeping habits, and perceived health. A questionnaire was used to assess a nationwide postal sample of 12-18-year-old Finns (6761…

  5. FIPSER: Performance study of a readout concept with few digitization levels for fast signals

    Energy Technology Data Exchange (ETDEWEB)

    Limyansky, B., E-mail: brent.limyansky@gatech.edu [School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, Atlanta (United States); Reese, R., E-mail: bobbeyreese@gmail.com [School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, Atlanta (United States); Cressler, J.D. [School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta (United States); Otte, A.N.; Taboada, I. [School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, Atlanta (United States); Ulusoy, C. [Dept. of Electrical and Computer Engineering, Michigan State University, East Lansing (United States)

    2016-11-21

    We discuss the performance of a readout system, Fixed Pulse Shape Efficient Readout (FIPSER), to digitize signals from detectors with a fixed pulse shape. In this study we are mainly interested in the readout of fast photon detectors like photomultipliers or Silicon photomultipliers. But the concept can be equally applied to the digitization of other detector signals. FIPSER is based on the flash analog to digital converter (FADC) concept, but has the potential to lower costs and power consumption by using an order of magnitude fewer discrete voltage levels. Performance is bolstered by combining the discretized signal with the knowledge of the underlying pulse shape. Simulated FIPSER data was reconstructed with two independent methods. One using a maximum likelihood method and the other using a modified χ{sup 2} test. Both methods show that utilizing 12 discrete voltage levels with a sampling rate of 4 samples per full width half maximum (FWHM) of the pulse achieves an amplitude resolution that is better than the Poisson limit for photon-counting experiments. The time resolution achieved in this configuration ranges between 0.02 and 0.16 FWHM and depends on the pulse amplitude. In a situation where the waveform is composed of two consecutive pulses the pulses can be separated if they are at least 0.05–0.30 FWHM apart with an amplitude resolution that is better than 20%.

  6. Technical difficulties and challenges for performing safety analysis on digital I and C systems

    International Nuclear Information System (INIS)

    Yih, Swu

    1996-01-01

    Performing safety analysis on digital I and C systems is an important task for nuclear safety analysts. The analysis results can not only confirm that the system is well-developed but also provide crucial evidence for licensing process. However, currently both I and C developers and regulators have difficulties in evaluating the safety of digital I and C systems. To investigate this problem, this paper propose a frame-based model to analyze the working and failure mechanisms of software and its interaction with the environment. Valid isomorphic relationship between the logical (software) and the physical (hardware environment) frame is identified as a major factor that determines the safe behavior of the software. The failures that may potentially cause the violation of isomorphic relations are also discussed. To perform safety analysis on digital I and C systems, analysts need to predict the effects incurred by such failures. However, due to lack of continuity, regularity, integrity, and high complexity of software structure, software does not have a stable and predictable pattern of behavior, which in turn makes the trustworthiness of results of software safety analysis susceptible. Our model can explain many troublesome events experienced by computer controlled systems. Implications and possible directions for improvement are also discussed. (author)

  7. Simulation of the High Performance Time to Digital Converter for the ATLAS Muon Spectrometer trigger upgrade

    International Nuclear Information System (INIS)

    Meng, X.T.; Levin, D.S.; Chapman, J.W.; Zhou, B.

    2016-01-01

    The ATLAS Muon Spectrometer endcap thin-Resistive Plate Chamber trigger project compliments the New Small Wheel endcap Phase-1 upgrade for higher luminosity LHC operation. These new trigger chambers, located in a high rate region of ATLAS, will improve overall trigger acceptance and reduce the fake muon trigger incidence. These chambers must generate a low level muon trigger to be delivered to a remote high level processor within a stringent latency requirement of 43 bunch crossings (1075 ns). To help meet this requirement the High Performance Time to Digital Converter (HPTDC), a multi-channel ASIC designed by CERN Microelectronics group, has been proposed for the digitization of the fast front end detector signals. This paper investigates the HPTDC performance in the context of the overall muon trigger latency, employing detailed behavioral Verilog simulations in which the latency in triggerless mode is measured for a range of configurations and under realistic hit rate conditions. The simulation results show that various HPTDC operational configurations, including leading edge and pair measurement modes can provide high efficiency (>98%) to capture and digitize hits within a time interval satisfying the Phase-1 latency tolerance.

  8. Does Performance in Digital Reading Relate to Computer Game Playing? A Study of Factor Structure and Gender Patterns in 15-Year-Olds' Reading Literacy Performance

    Science.gov (United States)

    Rasmusson, Maria; Åberg-Bengtsson, Lisbeth

    2015-01-01

    Data from a Swedish PISA-sample were used (1) to identify a digital reading factor, (2) to investigate gender differences in this factor (if found), and (3) to explore how computer game playing might relate to digital reading performance and gender. The analyses were conducted with structural equation modeling techniques. In addition to an overall…

  9. A Framework for Evaluating the Effects of Degraded Digital I and C Systems on Human Performance

    International Nuclear Information System (INIS)

    OHara, J.; Gunther, B.; Hughes, N.; Barnes, V.

    2009-01-01

    New and advanced reactors will use integrated digital instrumentation and control (I and C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator situation awareness and performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission has initiated a research project to investigate the effects of degraded I and C systems on human performance and plant operations. The ultimate objective of this project is to develop the technical basis for human factors review guidance for conditions of degraded I and C, including complete failure. Based on the results of this effort, NRC will determine the need for developing new guidance or revising NUREG-0800, NUREG-0711, NUREG-0700 and other pertinent NRC review guidance. This paper reports on the first phase of the research, the development of a framework for linking degraded I and C system conditions to human performance. The framework consists of three levels: I and C subsystems, human-system interfaces, and human performance. Each level is composed of a number of discrete elements. This paper will describe the elements at each level and their integration. In the next phase of the research, the framework will be used to systematically investigate the human performance consequences of various classes of failures

  10. Correlation between the physical performances measured from detectors and the diagnostic image quality in digital mammography

    International Nuclear Information System (INIS)

    Perez-Ponce, H.

    2009-05-01

    In digital mammography two approaches exist to estimate image quality. In the first approach, human observer assesses the lesion detection in mammograms. Unfortunately, such quality assessment is subject to interobserver variability, and requires a large amount of time and human resources. In the second approach, objective and human-independent parameters relating to image spatial resolution and noise (MTF and NPS) are used to evaluate digital detector performance; even if these parameters are objective, they are not directly related to lesion detection. A method leading to image quality assessment which is both human independent, and directly related to lesion detection is very important for the optimal use of mammographic units. This Ph.D thesis presents the steps towards such a method: the computation of realistic virtual images using an 'X ray source/digital detector' model taking into account the physical parameters of the detector (spatial resolution and noise measurements) measured under clinical conditions. From results obtained in this work, we have contributed to establish the link between the physical characteristics of detectors and the clinical quality of the image for usual exposition conditions. Furthermore, we suggest the use of our model for the creation of virtual images, in order to rapidly determine the optimal conditions in mammography, which usually is a long and tedious experimental process. This is an essential aspect to be taken into account for radioprotection of patients, especially in the context of organized mass screening of breast cancer. (author)

  11. Performance of waveform digitizers as a compact data acquisition system for the ISMRAN experiment

    International Nuclear Information System (INIS)

    Mitra, A.; Netrakanti, P.K.; Kashyap, V.K.S.; Behera, S.P.; Jha, V.; Mishra, D.K.; Pant, L.M.

    2016-01-01

    The Indian Scintillator Matrix for Reactor Anti-Neutrino (ISMRAN) detector is proposed at the Dhruva reactor, BARC, to measure the anti-neutrinos (υ-bar ) for the purpose of reactor monitoring and sterile neutrino search. A one ton detector, consisting of 100 plastic scintillator bars (10cm x 10cm x 100cm), wrapped with the Gadolinium (Gd) coated mylar foils and coupled with photomultiplier tubes (PMT) at both ends, is planned for this purpose. One of the key components for such an experiment is the development of a dedicated and economical data acquisition system (DAQ) for the detector setup. The FPGA based waveform digitizers are suitable for this purpose, where data from a large number of detectors need to be read out simultaneously. This effectively reduces the burden of the intermediate conventional pulse processing electronics between the detectors and the DAQ. We have procured the CAEN made 16 channel, model V1730, 14bit, 500 MS/s VME based waveform digitizers for this purpose. A series of measurements have been carried out to evaluate the performance of the digitizers. We are also working on the related auxiliary software and data format to be used extensively for ISMRAN DAQ

  12. Amorphous Zinc Oxide Integrated Wavy Channel Thin Film Transistor Based High Performance Digital Circuits

    KAUST Repository

    Hanna, Amir

    2015-12-04

    High performance thin film transistor (TFT) can be a great driving force for display, sensor/actuator, integrated electronics, and distributed computation for Internet of Everything applications. While semiconducting oxides like zinc oxide (ZnO) present promising opportunity in that regard, still wide area of improvement exists to increase the performance further. Here, we show a wavy channel (WC) architecture for ZnO integrated TFT which increases transistor width without chip area penalty, enabling high performance in material agnostic way. We further demonstrate digital logic NAND circuit using the WC architecture and compare it to the conventional planar architecture. The WC architecture circuits have shown 2× higher peak-to-peak output voltage for the same input voltage. They also have 3× lower high-to-low propagation delay times, respectively, when compared to the planar architecture. The performance enhancement is attributed to both extra device width and enhanced field effect mobility due to higher gate field electrostatics control.

  13. The role of long-term memory in digit-symbol test performance in young and older adults.

    Science.gov (United States)

    Stephens, R; Kaufman, A

    2009-03-01

    The psychological functions assessed by substitution tests, and the age-related performance decline, are not well understood. Here several aspects of long-term memory were manipulated across younger and older adults. A 45-page Digit-Symbol test was employed. Each page contained a 9-item digit symbol code-table and 9 response items. There were 9 study conditions with each condition deployed across 5 pages, or trials, of the test. The conditions were formed by crossing two within-subjects factors, each with 3 levels. The first factor, Digit Order, pertained to having the code table digits in numerical order vs. a pseudo-random order fixed across trials vs. a pseudo-random order that varied across trials. The second factor, Symbol Pairing, pertained to having a fixed digit-symbol pairing across trials vs. having a varying digit-symbol pairing across trials vs. having a novel set of 9 symbols introduced on each of the 5 trials. Including the additional factor, Age, resulted in a 2 x 3 x 3 mixed randomised block design. The older group was slowed, F(1, 22) = 17.267, p Symbol-Order interaction indicated that use of novel symbols disadvantaged only the older participants, F(1, 44) = 6.577, p = .014. While there was no evidence that incidental paired-associate learning or spatial memory affect digit-symbol performance, symbol familiarity may be important to digit symbol test completion in older adults. The benefit of ordinally arranged digits in the coding table highlights a fundamental process difference between Digit-Symbol and Symbol-Digit test formats.

  14. Ciberpunk y arte de los nuevos medios: performance y arte digital

    OpenAIRE

    Psarra, Afroditi

    2016-01-01

    La tesis doctoral Ciberpunk y Arte de los Nuevos Medios: Performance y Arte Digital consiste en la aproximación del fenómeno ciberpunk como expresión literaria y cinematográfica, en el estudio del arte de los nuevos medios, y en la reflexión artística que surge de la amalgama de estos conceptos. Su objetivo es comentar a un nivel multidisciplinario la influencia de la teoría y la estética ciberpunk en la construcción de mecanismos creativos, y estudiar la integración de las ideas del ciberpun...

  15. Description and Performance of an L-Band Radiometer with Digital Beamforming

    Directory of Open Access Journals (Sweden)

    Juan F. Marchan-Hernandez

    2010-12-01

    Full Text Available This paper presents the description and performance tests of an L-band microwave radiometer with Digital Beamforming (DBF, developed for the Passive Advanced Unit (PAU for ocean monitoring project. PAU is an instrument that combines, in a single receiver and without time multiplexing, a microwave radiometer at L-band (PAU-RAD and a GPS-reflectometer (PAU-GNSS-R. This paper focuses on the PAU‑RAD beamformer’s first results, analyzing the hardware and software required for the developed prototype. Finally, it discusses the first results measured in the Universitat Politècnica de Catalunya (UPC anechoic chamber.

  16. Decontamination of digital image sensors and assessment of electron microscope performance in a BSL-3 containment

    Directory of Open Access Journals (Sweden)

    Michael B. Sherman

    2015-05-01

    Full Text Available A unique biological safety level (BSL-3 cryo-electron microscopy facility with a 200 keV high-end cryo-electron microscope has been commissioned at the University of Texas Medical Branch (UTMB to study the structure of viruses and bacteria classified as select agents. We developed a microscope decontamination protocol based on chlorine dioxide gas with a continuous flow system. In this paper we report on testing digital camera sensors (both CCD and CMOS direct detector in a BSL-3 environment, and microscope performance after chlorine dioxide (ClO2 decontamination cycles.

  17. Performance analysis of the closed digital control circuit of reactor A-1

    International Nuclear Information System (INIS)

    Karpeta, C.; Volf, K.; Stirsky, P.; Roubal, S.; Muellerova, H.

    A computer-aided analysis is presented of the optimum digital control of the A-1 nuclear power plant reactor. The effect of index weighting matrices on the quality of control processes was studied for a deterministic case using the Separation Theorem for a linear time-discrete regulator problem with a quadratic performance index. Some properties were also investigated of the Kalman filter serving the process state estimation. An analysis is reported for a stochastic case, this for both time-invariant and time-variant Kalman filter gain matrix. (author)

  18. National Performance Benchmarks for Modern Screening Digital Mammography: Update from the Breast Cancer Surveillance Consortium.

    Science.gov (United States)

    Lehman, Constance D; Arao, Robert F; Sprague, Brian L; Lee, Janie M; Buist, Diana S M; Kerlikowske, Karla; Henderson, Louise M; Onega, Tracy; Tosteson, Anna N A; Rauscher, Garth H; Miglioretti, Diana L

    2017-04-01

    Purpose To establish performance benchmarks for modern screening digital mammography and assess performance trends over time in U.S. community practice. Materials and Methods This HIPAA-compliant, institutional review board-approved study measured the performance of digital screening mammography interpreted by 359 radiologists across 95 facilities in six Breast Cancer Surveillance Consortium (BCSC) registries. The study included 1 682 504 digital screening mammograms performed between 2007 and 2013 in 792 808 women. Performance measures were calculated according to the American College of Radiology Breast Imaging Reporting and Data System, 5th edition, and were compared with published benchmarks by the BCSC, the National Mammography Database, and performance recommendations by expert opinion. Benchmarks were derived from the distribution of performance metrics across radiologists and were presented as 50th (median), 10th, 25th, 75th, and 90th percentiles, with graphic presentations using smoothed curves. Results Mean screening performance measures were as follows: abnormal interpretation rate (AIR), 11.6 (95% confidence interval [CI]: 11.5, 11.6); cancers detected per 1000 screens, or cancer detection rate (CDR), 5.1 (95% CI: 5.0, 5.2); sensitivity, 86.9% (95% CI: 86.3%, 87.6%); specificity, 88.9% (95% CI: 88.8%, 88.9%); false-negative rate per 1000 screens, 0.8 (95% CI: 0.7, 0.8); positive predictive value (PPV) 1, 4.4% (95% CI: 4.3%, 4.5%); PPV2, 25.6% (95% CI: 25.1%, 26.1%); PPV3, 28.6% (95% CI: 28.0%, 29.3%); cancers stage 0 or 1, 76.9%; minimal cancers, 57.7%; and node-negative invasive cancers, 79.4%. Recommended CDRs were achieved by 92.1% of radiologists in community practice, and 97.1% achieved recommended ranges for sensitivity. Only 59.0% of radiologists achieved recommended AIRs, and only 63.0% achieved recommended levels of specificity. Conclusion The majority of radiologists in the BCSC surpass cancer detection recommendations for screening

  19. Case base classification on digital mammograms: improving the performance of case base classifier

    Science.gov (United States)

    Raman, Valliappan; Then, H. H.; Sumari, Putra; Venkatesa Mohan, N.

    2011-10-01

    Breast cancer continues to be a significant public health problem in the world. Early detection is the key for improving breast cancer prognosis. The aim of the research presented here is in twofold. First stage of research involves machine learning techniques, which segments and extracts features from the mass of digital mammograms. Second level is on problem solving approach which includes classification of mass by performance based case base classifier. In this paper we build a case-based Classifier in order to diagnose mammographic images. We explain different methods and behaviors that have been added to the classifier to improve the performance of the classifier. Currently the initial Performance base Classifier with Bagging is proposed in the paper and it's been implemented and it shows an improvement in specificity and sensitivity.

  20. The ATLAS project: The effects of a constructionist digital laboratory project on undergraduate laboratory performance.

    Science.gov (United States)

    Shoepe, Todd C; Cavedon, Dana K; Derian, Joseph M; Levy, Celine S; Morales, Amy

    2015-01-01

    Anatomical education is a dynamic field where developments in the implementation of constructive, situated-learning show promise in improving student achievement. The purpose of this study was to examine the effectiveness of an individualized, technology heavy project in promoting student performance in a combined anatomy and physiology laboratory course. Mixed-methods research was used to compare two cohorts of anatomy laboratories separated by the adoption of a new laboratory atlas project, which were defined as preceding (PRE) and following the adoption of the Anatomical Teaching and Learning Assessment Study (ATLAS; POST). The ATLAS project required the creation of a student-generated, photographic atlas via acquisition of specimen images taken with tablet technology and digital microscope cameras throughout the semester. Images were transferred to laptops, digitally labeled and photo edited weekly, and compiled into a digital book using Internet publishing freeware for final project submission. An analysis of covariance confirmed that student final examination scores were improved (P project (PRE, n = 75; POST, n = 90; means ± SE; 74.9 ± 0.9 versus 78.1 ± 0.8, respectively) after controlling for cumulative student grade point average. Analysis of questionnaires collected (n = 68) from the post group suggested students identified with atlas objectives, appreciated the comprehensive value in final examination preparation, and the constructionism involved, but recommended alterations in assignment logistics and the format of the final version. Constructionist, comprehensive term-projects utilizing student-preferred technologies could be used to improve performance toward student learning outcomes. © 2014 American Association of Anatomists.

  1. An adaptive toolkit for image quality evaluation in system performance test of digital breast tomosynthesis

    Science.gov (United States)

    Zhang, Guozhi; Petrov, Dimitar; Marshall, Nicholas; Bosmans, Hilde

    2017-03-01

    Digital breast tomosynthesis (DBT) is a relatively new diagnostic imaging modality for women. Currently, various models of DBT systems are available on the market and the number of installations is rapidly increasing. EUREF, the European Reference Organization for Quality Assured Breast Screening and Diagnostic Services, has proposed a preliminary Guideline - protocol for the quality control of the physical and technical aspects of digital breast tomosynthesis systems, with an ultimate aim of providing limiting values guaranteeing proper performance for different applications of DBT. In this work, we introduce an adaptive toolkit developed in accordance with this guideline to facilitate the process of image quality evaluation in DBT performance test. This toolkit implements robust algorithms to quantify various technical parameters of DBT images and provides a convenient user interface in practice. Each test is built into a separate module with configurations set corresponding to the European guideline, which can be easily adapted to different settings and extended with additional tests. This toolkit largely improves the efficiency for image quality evaluation of DBT. It is also going to evolve with the development of protocols in quality control of DBT systems.

  2. Sloan Digital Sky Survey: Performance and Lessons Learned from the First Two Years of Operations

    Science.gov (United States)

    Boroski, William N.; Gunn, James E.; Kron, Richard G.; Peoples, John, Jr.

    2002-12-01

    Over a 5-year observing period, the Sloan Digital Sky Survey (SDSS) will acquire data to construct a digital 5-color photometric map of the Northern Galactic sky to about 23rd magnitude, and a correspondingly large and homogeneous spectroscopic survey. The SDSS is in a unique class of projects, in that all aspects of the SDSS infrastructure, from the telescopes and instruments, to software and operations staffing, were designed and assembled specifically to conduct this Survey. To ensure success, observing operations are run in production mode and performance metrics are used to measure progress over time. The methodology of preparing the performance baseline plan, and an assessment of Survey progress after two full years of operation, are reviewed and some lessons learned discussed. In particular, the SDSS has benefited greatly by asking peers in the field to participate in external reviews that periodically assess performance and offer independent, fresh views of potential areas of concerns. Additionally, difficulties caused by the absence of an experienced systems-engineering staff during the final phase of construction and commissioning are reviewed. The challenges of building a production machine out of complex and state-of-the-art sub-systems cannot be overstated. In the case of the SDSS, insufficient systems engineering led to problems meeting initial image quality requirements, primarily because of problems with the thermal performance of the telescope and its environment. A concerted campaign to deal with these issues was successful, but that success came rather later than we would have liked. The improvements made to address the situation, and the resulting increase in operational performance, are discussed.

  3. Effect of noise on the performance of Digital Charge Comparison method for n-γ discrimination

    International Nuclear Information System (INIS)

    Singh, Harleen; Mehra, Rohit

    2017-01-01

    The neutron-gamma discrimination from a mixed radiation field is of prime importance in the field of nuclear safeguards, nuclear fission, radiation therapy etc. The liquid scintillators are widely used for n-γ discrimination as the relative decay rate of neutron pulse is less as compared to γ - ray in these detectors.The most popular and simple technique for pulse shape discrimination (PSD) is the charge comparison (CC). Due to the availability of fast ADCs and FPGAs, the traditional analogue techniques can be implemented in digital domain by sampling the PMT pulses. The performance of a PSD method depends on various parameters like sampling rate, noise distortion in the pulses the duration of processing gate etc. In this paper, the effect of noise levels on the performance of CC method is investigated at optimized processing gate

  4. A Mixed-Method Approach on Digital Educational Games for K12: Gender, Attitudes and Performance

    Science.gov (United States)

    Law, Effie Lai-Chong; Gamble, Tim; Schwarz, Daniel; Kickmeier-Rust, Michael D.; Holzinger, Andreas

    Research on the influence of gender on attitudes towards and performance in digital educational games (DEGs) has quite a long history. Generally, males tend to play such games more engagingly than females, consequently attitude and performance of males using DEGs should be presumably higher than that of females. This paper reports an investigation of a DEG, which was developed to enhance the acquisition of geographical knowledge, carried out on British, German and Austrian K12 students aged between 11 and 14. Methods include a survey on initial design concepts, user tests on the system and two single-gender focus groups. Gender and cultural differences in gameplay habit, game type preferences and game character perceptions were observed. The results showed that both genders similarly improved their geographical knowledge, although boys tended to have a higher level of positive user experience than the girls. The qualitative data from the focus groups illustrated some interesting gender differences in perceiving various aspects of the game.

  5. Digital gastrointestinal imaging: Effect of pixel size of subtle mucosal abnormalities on observer performance

    International Nuclear Information System (INIS)

    Kastan, D.J.; Ackerman, L.V.; Feczko, P.J.

    1986-01-01

    Radiographs from double-contrast colon examinations demonstrating subtle mucosal changes of inflammatory bowel disease and radiographs showing normal colon were digitized (0.1-mm, 0.2-mm, 0.4-mm and 0.8-mm pixel sizes). Ten radiologists interpreted the laser-printed images. Receiver operating characteristic analysis was performed. The results indicated that (1) the sensitivity of radiography in detecting subtle mucosal abnormalities improved as resolution improved; (2) more experience readers performed remarkably well even at the poorer levels of resolution; (3) the resolution necessary for evaluating the colonic mucosa was less than expected; and (4) at low noise levels, conventional television fluoroscopy may have sufficient resolution for mucosal evaluation

  6. The Impact of Digital Financial Services on Firm's Performance : A Literature Review

    NARCIS (Netherlands)

    Abbasi, Tariq; Weigand, Hans

    Digital Financial Services continue to expand and replace the delivery of traditional banking services to the customers through innovative technologies to meet the growing complex needs and globalization challenges. These diversified digital products help the organizations (service providers) to

  7. The effect of pitch, rhythm, and familiarity on working memory and anxiety as measured by digit recall performance.

    Science.gov (United States)

    Silverman, Michael J

    2010-01-01

    The purpose of this study was to isolate and quantitatively evaluate the effects of pitch and rhythm of unfamiliar and familiar melodies on working memory and anxiety as measured by sequential digit recall performance. Participants (N = 60) listened to 6 treatment conditions each consisting of 9 randomized monosyllabic digits. The digits were paired with (a) a familiar melody and pitch only, (b) a familiar melody and rhythm only, (c) a familiar melody with both pitch and rhythm, (d) an unfamiliar melody with pitch only, (e) an unfamiliar melody with rhythm only, and (f) an unfamiliar melody with both pitch and rhythm. The 6 different treatments were counterbalanced using a Latin square design in an attempt to control for order effects. Participants rated their state anxiety on a Likert-type scale before, midway through, and after the digits test. No statistically significant order, learning, or practice effects were found. A 3-way repeated-measures ANOVA indicated a statistically significant difference in digit recall performance across musical element conditions and groups. Results indicated that music majors outperformed nonmusic majors on the digit recall task. Participants were able to recall digits from the rhythm condition most accurately while recalling digits from pitch only and both pitch and rhythm conditions the least accurately. Graphic analysis of treatment as a function of sequential position indicated digit recall was best during conditions of primacy and recency. No main effects were found for the familiarity condition. Additionally, no main effects or interactions were found for the anxiety variable. The results of this study are congruent with existing working memory and music literature suggesting that pairing information with rhythm can facilitate recall, music majors outperform non-music majors, and recall accuracy is best in positions of primacy and recency. Implications for practice in therapy and education are made as well as suggestions for

  8. Effects of rapid digitalization on total and regional myocardial performance in patients with coronary artery disease.

    Science.gov (United States)

    Ferlinz, J; DelVicario, M; Aronow, W S

    1978-09-01

    In order to evaluate the effects of rapid digitalization on LV volumes, ejection fraction, and asynergy, 21 patients without heart failure were studied with a combination of hemodynamic and angiographic techniques before and after administration of intravenous ouabain (0.007 mg./Kg.). Seven patients had no CAD and served as normal (control) subjects (Group I), while 14 patients had extensive coronary disease (Group II). All pre-ouabain parameters were within the normal limits in Group I. After ouabain infusion, all indices of LV contractility: dP/dt, VCF, and ejection fraction rose significantly in the normal group, while LV filling pressure and end-diastolic volume remained unchanged. The baseline hemodynamic and volumetric values for Group II patients corresponded closely to their normal (Group I) counterparts, and exhibited similar changes after ouabain administration. Eight patients in Group II also had regional disorders of LV contractility, delineated by 23 abnormal hemiaxes of shortening. After ouabain, 15 out of 23 asynergic segments (65 per cent) improved, seven remained unchanged, and one worsened. It is therefore concluded that rapid digitalization not only enhances LV performance in normal subjects and in patients with CAD, but can also markedly reduce the extent of LV asynergy.

  9. Performance of low-cost X-ray area detectors with consumer digital cameras

    International Nuclear Information System (INIS)

    Panna, A.; Gomella, A.A.; Harmon, K.J.; Chen, P.; Miao, H.; Bennett, E.E.; Wen, H.

    2015-01-01

    We constructed X-ray detectors using consumer-grade digital cameras coupled to commercial X-ray phosphors. Several detector configurations were tested against the Varian PaxScan 3024M (Varian 3024M) digital flat panel detector. These include consumer cameras (Nikon D800, Nikon D700, and Nikon D3X) coupled to a green emission phosphor in a back-lit, normal incidence geometry, and in a front-lit, oblique incidence geometry. We used the photon transfer method to evaluate detector sensitivity and dark noise, and the edge test method to evaluate their spatial resolution. The essential specifications provided by our evaluation include discrete charge events captured per mm 2 per unit exposure surface dose, dark noise in equivalents of charge events per pixel, and spatial resolution in terms of the full width at half maximum (FWHM) of the detector's line spread function (LSF). Measurements were performed using a tungsten anode X-ray tube at 50 kVp. The results show that the home-built detectors provide better sensitivity and lower noise than the commercial flat panel detector, and some have better spatial resolution. The trade-off is substantially smaller imaging areas. Given their much lower costs, these home-built detectors are attractive options for prototype development of low-dose imaging applications

  10. Does digital mammography suppose an advance in early diagnosis? Trends in performance indicators 6 years after digitalization.

    Science.gov (United States)

    Sala, Maria; Domingo, Laia; Macià, Francesc; Comas, Mercè; Burón, Andrea; Castells, Xavier

    2015-03-01

    To provide a complete evaluation of the long-term impact of full-field digital mammography (FFDM) on the improvement of early diagnosis in a population-based screening program. We included 82,961 screen-film mammograms (SFM) and 79,031 FFDM from women aged 50-69 screened biennially from 1995-2010 in Spain and followed-up to 2012. The first screening round of the program was excluded. Rates of cancer detection, interval cancer, tumoral characteristics and other quality indicators were compared between SFM and FFDM periods using the Chi-square test. Multivariate logistic regression models were fitted. Detection of ductal carcinoma in situ (DCIS) significantly increased with FFDM (0.05 % vs 0.09 %; p = 0.010), along with the proportion of small invasive cancers (Digitalization has supposed an improvement in early diagnosis because DCIS and small invasive cancers increased without a change in detection rate. Moreover, false-positive reduction without an increase in the interval cancer rate was confirmed.

  11. The effects of gray scale image processing on digital mammography interpretation performance.

    Science.gov (United States)

    Cole, Elodia B; Pisano, Etta D; Zeng, Donglin; Muller, Keith; Aylward, Stephen R; Park, Sungwook; Kuzmiak, Cherie; Koomen, Marcia; Pavic, Dag; Walsh, Ruth; Baker, Jay; Gimenez, Edgardo I; Freimanis, Rita

    2005-05-01

    To determine the effects of three image-processing algorithms on diagnostic accuracy of digital mammography in comparison with conventional screen-film mammography. A total of 201 cases consisting of nonprocessed soft copy versions of the digital mammograms acquired from GE, Fischer, and Trex digital mammography systems (1997-1999) and conventional screen-film mammograms of the same patients were interpreted by nine radiologists. The raw digital data were processed with each of three different image-processing algorithms creating three presentations-manufacturer's default (applied and laser printed to film by each of the manufacturers), MUSICA, and PLAHE-were presented in soft copy display. There were three radiologists per presentation. Area under the receiver operating characteristic curve for GE digital mass cases was worse than screen-film for all digital presentations. The area under the receiver operating characteristic for Trex digital mass cases was better, but only with images processed with the manufacturer's default algorithm. Sensitivity for GE digital mass cases was worse than screen film for all digital presentations. Specificity for Fischer digital calcifications cases was worse than screen film for images processed in default and PLAHE algorithms. Specificity for Trex digital calcifications cases was worse than screen film for images processed with MUSICA. Specific image-processing algorithms may be necessary for optimal presentation for interpretation based on machine and lesion type.

  12. On the Performance Analysis of Digital Communications over Weibull-Gamma Channels

    KAUST Repository

    Ansari, Imran Shafique

    2015-05-01

    In this work, the performance analysis of digital communications over a composite Weibull-Gamma (WG) multipath-fading and shadowing channel is presented wherein WG distribution is appropriate for modeling fading environments when multipath is superimposed on shadowing. More specifically, in this work, exact closed-form expressions are derived for the probability density function, the cumulative distribution function, the moment generating function, and the moments of a composite WG channel. Capitalizing on these results, new exact closed-form expressions are offered for the outage probability, the higher- order amount of fading, the average error rate for binary and M-ary modulation schemes, and the ergodic capacity under various types of transmission policies, mostly in terms of Meijer\\'s G functions. These new analytical results were also verified via computer-based Monte-Carlo simulation results. © 2015 IEEE.

  13. On the Performance Analysis of Digital Communications over Weibull-Gamma Channels

    KAUST Repository

    Ansari, Imran Shafique; Alouini, Mohamed-Slim

    2015-01-01

    In this work, the performance analysis of digital communications over a composite Weibull-Gamma (WG) multipath-fading and shadowing channel is presented wherein WG distribution is appropriate for modeling fading environments when multipath is superimposed on shadowing. More specifically, in this work, exact closed-form expressions are derived for the probability density function, the cumulative distribution function, the moment generating function, and the moments of a composite WG channel. Capitalizing on these results, new exact closed-form expressions are offered for the outage probability, the higher- order amount of fading, the average error rate for binary and M-ary modulation schemes, and the ergodic capacity under various types of transmission policies, mostly in terms of Meijer's G functions. These new analytical results were also verified via computer-based Monte-Carlo simulation results. © 2015 IEEE.

  14. Modulation format dependence of digital nonlinearity compensation performance in optical fibre communication systems.

    Science.gov (United States)

    Xu, Tianhua; Shevchenko, Nikita A; Lavery, Domaniç; Semrau, Daniel; Liga, Gabriele; Alvarado, Alex; Killey, Robert I; Bayvel, Polina

    2017-02-20

    The relationship between modulation format and the performance of multi-channel digital back-propagation (MC-DBP) in ideal Nyquist-spaced optical communication systems is investigated. It is found that the nonlinear distortions behave independent of modulation format in the case of full-field DBP, in contrast to the cases of electronic dispersion compensation and partial-bandwidth DBP. It is shown that the minimum number of steps per span required for MC-DBP depends on the chosen modulation format. For any given target information rate, there exists a possible trade-off between modulation format and back-propagated bandwidth, which could be used to reduce the computational complexity requirement of MC-DBP.

  15. 37 CFR 260.2 - Royalty fees for the digital performance of sound recordings and the making of ephemeral...

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Royalty fees for the digital... Licensee's monthly royalty fee for the public performance of sound recordings pursuant to 17 U.S.C. 114(d..., 2007, a Licensee's monthly royalty fee for the public performance of sound recordings pursuant to 17 U...

  16. Modelling the imaging performance and low contrast detectability in digital mammography

    International Nuclear Information System (INIS)

    Spyropoulou, V; Kalyvas, N; Gaitanis, A; Michail, C; Panayiotakis, G; Kandarakis, I

    2009-01-01

    A digital x-ray mammography is a modern method for the early detection of breast cancer. The quality of a mammography image depends on various factors, the detector structure and performance being of primary importance. The aim of this work was to develop an analytical model simulating the imaging performance of a new commercially available digital mammography detector. This was achieved within the framework of the linear cascaded systems (LCS) theory. System analysis has allowed the estimation of important image quality metrics such as the Modulation Transfer Function (MTF), the Noise Power Spectrum (NPS) and the Detective Quantum Efficiency (DQE). The detector was an indirect detection system consisting of a large area, 100μm thick, CsI:TI scintillator coupled to an active matrix array of amorphous silicon (a-Si:H) photodiodes combined with thin film transistors (TFT). Pixel size was 100μm, while the active pixel dimension was 70μm. MTF and DQE data were calculated for air kerma conditions of 25, 53, 67 μGy using a 28 kVp Mo-Mo x-ray spectrum. The theoretical results were compared with published experimental data. The deviation between the theoretical and experimental MTF curves was less than 4%, while the DQE differences were found at an acceptable level. The model was also used to estimate system's capability to detect low contrast objects in the breast. It was estimated that, in the breast gland, low contrast structures larger than 1.4mm can be adequately identified by the above system.

  17. Discrepancies between bilinguals' performance on the Spanish and English versions of the WAIS Digit Span task: Cross-cultural implications.

    Science.gov (United States)

    López, Enrique; Steiner, Alexander J; Hardy, David J; IsHak, Waguih W; Anderson, W Brantley

    2016-01-01

    This study explored within-subjects differences in the performance of 40 bilingual participants on the English and Spanish versions of the Wechsler Adult Intelligence Scale (WAIS) Digit Span task. To test the linguistic hypothesis that individuals would perform worse in Spanish because of its syllabic demand, we compared the number of syllables correctly recalled by each participant for every correct trial. Our analysis of the correct number of syllables remembered per trial showed that participants performed significantly better (i.e., recalling more syllables) in Spanish than in English on the total score. Findings suggest the Spanish version of the Digit Span (total score) was significantly more difficult than the English version utilizing traditional scoring methods. Moreover, the Forward Trial, rather than the Backward Trial, was more likely to show group differences between both language versions. Additionally, the Spanish trials of the Digit Span were correlated with language comprehension and verbal episodic memory measures, whereas the English trials of the Digit Span were correlated with confrontational naming and verbal fluency tasks. The results suggest that more research is necessary to further investigate other cognitive factors, rather than just syllabic demand, that might contribute to performance and outcome differences on the WAIS Digit Span in Spanish-English bilinguals.

  18. Imaging performance of an amorphous selenium digital mammography detector in a breast tomosynthesis system

    International Nuclear Information System (INIS)

    Zhao Bo; Zhao Wei

    2008-01-01

    In breast tomosynthesis a rapid sequence of N images is acquired when the x-ray tube sweeps through different angular views with respect to the breast. Since the total dose to the breast is kept the same as that in regular mammography, the exposure used for each image of tomosynthesis is 1/N. The low dose and high frame rate pose a tremendous challenge to the imaging performance of digital mammography detectors. The purpose of the present work is to investigate the detector performance in different operational modes designed for tomosynthesis acquisition, e.g., binning or full resolution readout, the range of view angles, and the number of views N. A prototype breast tomosynthesis system with a nominal angular range of ±25 deg. was used in our investigation. The system was equipped with an amorphous selenium (a-Se) full field digital mammography detector with pixel size of 85 μm. The detector can be read out in full resolution or 2x1 binning (binning in the tube travel direction). The focal spot blur due to continuous tube travel was measured for different acquisition geometries, and it was found that pixel binning, instead of focal spot blur, dominates the detector modulation transfer function (MTF). The noise power spectrum (NPS) and detective quantum efficiency (DQE) of the detector were measured with the exposure range of 0.4-6 mR, which is relevant to the low dose used in tomosynthesis. It was found that DQE at 0.4 mR is only 20% less than that at highest exposure for both detector readout modes. The detector temporal performance was categorized as lag and ghosting, both of which were measured as a function of x-ray exposure. The first frame lags were 8% and 4%, respectively, for binning and full resolution mode. Ghosting is negligible and independent of the frame rate. The results showed that the detector performance is x-ray quantum noise limited at the low exposures used in each view of tomosynthesis, and the temporal performance at high frame rate (up to

  19. The Effect of Degraded Digital Instrumentation and Control systems on Human-system Interfaces and Operator Performance

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, B.; Martinez-Guridi, G.; Xing, J.; Barnes, V.

    2010-01-01

    Integrated digital instrumentation and control (I and C) systems in new and advanced nuclear power plants (NPPs) will support operators in monitoring and controlling the plants. Even though digital systems typically are expected to be reliable, their potential for degradation or failure significantly could affect the operators performance and, consequently, jeopardize plant safety. This U.S. Nuclear Regulatory Commission (NRC) research investigated the effects of degraded I and C systems on human performance and on plant operations. The objective was to develop technical basis and guidance for human factors engineering (HFE) reviews addressing the operator's ability to detect and manage degraded digital I and C conditions. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we evaluated the potential effects of selected failure modes of the digital feedwater control system of a currently operating pressurized water reactor (PWR) on human-system interfaces (HSIs) and the operators performance. Our findings indicated that I and C degradations are prevalent in plants employing digital systems, and the overall effects on the plant's behavior can be significant, such as causing a reactor trip or equipment to operate unexpectedly. I and C degradations may affect the HSIs used by operators to monitor and control the plant. For example, deterioration of the sensors can complicate the operators interpretation of displays, and sometimes may mislead them by making it appear that a process disturbance has occurred. We used the findings as the technical basis upon which to develop HFE review guidance.

  20. Decreasing radiation doses in digital subtraction angiographies consecutively performed by trainees

    International Nuclear Information System (INIS)

    Xu, G.; Zhao, W.; Zheng, L.; Fan, X.; Yin, Q.; Liu, X.

    2012-01-01

    Digital subtraction angiography (DSA) performed by trainees may be related to increased radiation exposure. This study was aimed to investigate and quantify this learning effect, with fluoroscopy time and dose-area product (DAP) as parameters. We collected procedure data of the first to the fortieth cerebral DSA consecutively performed by 13 trainees in a training centre. DAP, procedure time, fluoroscopy time, number of cine-frames of the first 20 DSA procedures performed by these trainees were compared with that of the second 20 procedures. There was no significant difference concerning the procedure time between the first and the second 20 procedures (56.3 ±29.5 vs 51.5±20.2 min, p = 0.113). Numbers of cine-frames were very similar between the first and the second 20 procedures (750.7 ±290.3 vs 744.5 ±188.7, p = 0.830). Fluoroscopy time of the first 20 procedures was significantly longer than that of the second 20 procedures (17.8 ±15.4 vs 12.6 ±9.0, p = 0.001). DAP of the first 20 procedures was significantly higher than that of the second 20 procedures (6.4 ±4.9 vs 3.8 ±1.8, p < 0.001). DAP was correlated significantly with the performer's experience (R = -0.288, p < 0.001). There exists a learning effect of radiation exposure during cerebral DSA procedures performed by trainees. The learning effect is significant during the first 20 procedures, and becomes insignificant after 20 procedures. Insufficient catheter skills in novice trainees may be one reason for this effect. (authors)

  1. Validity of the Symbol Digit Modalities Test as a cognition performance outcome measure for multiple sclerosis.

    Science.gov (United States)

    Benedict, Ralph Hb; DeLuca, John; Phillips, Glenn; LaRocca, Nicholas; Hudson, Lynn D; Rudick, Richard

    2017-04-01

    Cognitive and motor performance measures are commonly employed in multiple sclerosis (MS) research, particularly when the purpose is to determine the efficacy of treatment. The increasing focus of new therapies on slowing progression or reversing neurological disability makes the utilization of sensitive, reproducible, and valid measures essential. Processing speed is a basic elemental cognitive function that likely influences downstream processes such as memory. The Multiple Sclerosis Outcome Assessments Consortium (MSOAC) includes representatives from advocacy organizations, Food and Drug Administration (FDA), European Medicines Agency (EMA), National Institute of Neurological Disorders and Stroke (NINDS), academic institutions, and industry partners along with persons living with MS. Among the MSOAC goals is acceptance and qualification by regulators of performance outcomes that are highly reliable and valid, practical, cost-effective, and meaningful to persons with MS. A critical step for these neuroperformance metrics is elucidation of clinically relevant benchmarks, well-defined degrees of disability, and gradients of change that are deemed clinically meaningful. This topical review provides an overview of research on one particular cognitive measure, the Symbol Digit Modalities Test (SDMT), recognized as being particularly sensitive to slowed processing of information that is commonly seen in MS. The research in MS clearly supports the reliability and validity of this test and recently has supported a responder definition of SDMT change approximating 4 points or 10% in magnitude.

  2. The Complexities of Digital Storytelling: Factors Affecting Performance, Production, and Project Completion

    Science.gov (United States)

    Gobel, Peter; Kano, Makimi

    2016-01-01

    Digital storytelling projects provide a variety of opportunities for learning in the language classroom, but along with these opportunities come a number of challenges for both pedagogy and technology. This presentation describes an ongoing multi-method study into factors involved in task-based learning using digital storytelling. Using intact…

  3. Technology Knowledge Self-Assessment and Pre-Test Performance among Digital Natives

    Science.gov (United States)

    Nelms, Keith R.

    2015-01-01

    According to education pundits, traditional-age college students are "digital natives" inherently savvy in digital technology due to their constant exposure to technology from an early age. This widely held meme is at odds with observation in the college classroom. In this research, college students in an introductory information…

  4. Evaluation of the technical performance of three different commercial digital breast tomosynthesis systems in the clinical environment

    NARCIS (Netherlands)

    Rodriguez Ruiz, A.; Castillo, M.; Garayoa, J.; Chevalier, M.

    2016-01-01

    The aim of this work was to research and evaluate the performance of three different digital breast tomosynthesis (DBT) systems in the clinical environment (Siemens Mammomat Inspiration, Hologic Selenia Dimensions, and Fujifilm Amulet Innovality). The characterization included the study of the

  5. High speed high stakes scoring rule: assessing the performance of a new scoring rule for digital asssesment

    NARCIS (Netherlands)

    Klinkenberg, S.; Kalz, M.; Ras, E.

    2014-01-01

    In this paper we will present the results of a three year subsidized research project investigating the performance of a new scoring rule for digital assessment. The scoring rule incorporates response time and accuracy in an adaptive environment. The project aimed to assess the validity and

  6. Performances on Symbol Digit Modalities Test, Color Trails Test, and modified Stroop test in a healthy, elderly Danish sample

    DEFF Research Database (Denmark)

    Vogel, Asmus; Stokholm, Jette; Jørgensen, Kasper

    2013-01-01

    This study presents Danish data for the Symbol Digit Modalities Test (SDMT), Color Trails Test (CTT), and a modified Stroop test from 100 subjects aged 60-87 years. Among the included demographic variables, age had the highest impact on test performances. Thus, the study presents separate data...

  7. Effect of yoga relaxation techniques on performance of digit-letter substitution task by teenagers

    Directory of Open Access Journals (Sweden)

    Pradhan Balaram

    2009-01-01

    Full Text Available Background/Aims : Memory and selective attention are important skills for academic and professional performance. Techniques to improve these skills are not taught either in education or company training courses. Any system which can systematically improve these skills will be of value in schools, universities, and workplaces. Aims:To investigate possible improvements in memory and selective attention, as measured by the Digit-Letter Substitution Task (DLST, due to practice of Cyclic Meditation (CM, a yoga relaxation technique, as compared to Supine Rest (SR. Materials and Methods : Subjects consisted of 253 school students, 156 boys, 97 girls, in the age range 13-16 years, who were attending a 10-day yoga training course during summer vacation. The selected subjects had English as their medium of instruction in school and they acted as their own controls. They were allocated to two groups, and tested on the DLST, immediately before and after 22.5 minutes practice of CM on one day, and immediately before and after an equal period of SR on the other day. The first group performed CM on day 9 and SR on day 10. For the second group, the order was reversed. Results : Within each group pre-post test differences were significant for both the relaxation techniques. The magnitude of net score improvement was greater after SR (7.85% compared to CM (3.95%. Significance levels were P < 0.4 x 10 -9 for SR and P < 0.1 x 10 -3 for CM. The number of wrong attempts also increased significantly on both interventions, even after removing two outlier data points on day 1 in the SR group. Conclusions: Both CM and SR lead to improvement in performance on the DLST. However, these relaxation techniques lead to more wrong cancellation errors.

  8. Performance study of Philips digital silicon photomultiplier coupled to scintillating crystals

    CERN Document Server

    Liu, Z.; Auffray, E.; Lecoq, P.; Paganoni, M.

    2016-01-01

    Silicon photomultipliers (SiPMs) and scintillators are often arranged in the shape of arrays in Positron Emission Tomography (PET) systems. Digital SiPMs provide signal readout in single photon avalanche diode (SPAD) level. From the photon count rate measurement of each SPAD cell of digital SiPM, we found that the output scintillating photons distribute in an area larger than the scintillator physical coupling area. Taking advantage of the possibility to enable/disable individual cells of the digital SiPM, a group of Lutetium-yttrium oxyorthosilicate (LYSO) crystals with different dimensions coupled to a digital SiPM was used to study the influence of using different SiPM active area on the number of photons detected, energy resolution and coincidence time resolution (CTR). For the same crystal coupled to the digital SiPM, the larger the active area of digital SiPM, the higher the number of photons detected. The larger active area of the digital SiPM also results in a better energy resolution after saturation...

  9. An objective protocol for comparing the noise performance of silver halide film and digital sensor

    Science.gov (United States)

    Cao, Frédéric; Guichard, Frédéric; Hornung, Hervé; Tessière, Régis

    2012-01-01

    Digital sensors have obviously invaded the photography mass market. However, some photographers with very high expectancy still use silver halide film. Are they only nostalgic reluctant to technology or is there more than meets the eye? The answer is not so easy if we remark that, at the end of the golden age, films were actually scanned before development. Nowadays film users have adopted digital technology and scan their film to take advantage from digital processing afterwards. Therefore, it is legitimate to evaluate silver halide film "with a digital eye", with the assumption that processing can be applied as for a digital camera. The article will describe in details the operations we need to consider the film as a RAW digital sensor. In particular, we have to account for the film characteristic curve, the autocorrelation of the noise (related to film grain) and the sampling of the digital sensor (related to Bayer filter array). We also describe the protocol that was set, from shooting to scanning. We then present and interpret the results of sensor response, signal to noise ratio and dynamic range.

  10. Performance Analysis of Video Transmission Using Sequential Distortion Minimization Method for Digital Video Broadcasting Terrestrial

    Directory of Open Access Journals (Sweden)

    Novita Astin

    2016-12-01

    Full Text Available This paper presents about the transmission of Digital Video Broadcasting system with streaming video resolution 640x480 on different IQ rate and modulation. In the video transmission, distortion often occurs, so the received video has bad quality. Key frames selection algorithm is flexibel on a change of video, but on these methods, the temporal information of a video sequence is omitted. To minimize distortion between the original video and received video, we aimed at adding methodology using sequential distortion minimization algorithm. Its aim was to create a new video, better than original video without significant loss of content between the original video and received video, fixed sequentially. The reliability of video transmission was observed based on a constellation diagram, with the best result on IQ rate 2 Mhz and modulation 8 QAM. The best video transmission was also investigated using SEDIM (Sequential Distortion Minimization Method and without SEDIM. The experimental result showed that the PSNR (Peak Signal to Noise Ratio average of video transmission using SEDIM was an increase from 19,855 dB to 48,386 dB and SSIM (Structural Similarity average increase 10,49%. The experimental results and comparison of proposed method obtained a good performance. USRP board was used as RF front-end on 2,2 GHz.

  11. Fast digital envelope detector based on generalized harmonic wavelet transform for BOTDR performance improvement

    International Nuclear Information System (INIS)

    Yang, Wei; Yang, Yuanhong; Yang, Mingwei

    2014-01-01

    We propose a fast digital envelope detector (DED) based on the generalized harmonic wavelet transform to improve the performance of coherent heterodyne Brillouin optical time domain reflectometry. The proposed DED can obtain undistorted envelopes due to the zero phase-shift ideal bandpass filter (BPF) characteristics of the generalized harmonic wavelet (GHW). Its envelope average ability benefits from the passband designing flexibility of the GHW, and its demodulation speed can be accelerated by using a fast algorithm that only analyses signals of interest within the passband of the GHW with reduced computational complexity. The feasibility and advantage of the proposed DED are verified by simulations and experiments. With an optimized bandwidth, Brillouin frequency shift accuracy improvements of 19.4% and 11.14%, as well as envelope demodulation speed increases of 39.1% and 24.9%, are experimentally attained by the proposed DED over Hilbert transform (HT) and Morlet wavelet transform (MWT) based DEDs, respectively. Spatial resolution by the proposed DED is undegraded, which is identical to the undegraded value by HT-DED with an allpass filter characteristic and better than the degraded value by MWT-DED with a Gaussian BPF characteristic. (paper)

  12. A comparison of the performance of modern screen-film and digital mammography systems

    Energy Technology Data Exchange (ETDEWEB)

    Monnin, P [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Gutierrez, D [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Bulling, S [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Lepori, D [Department of Radiology, University Hospital Center (CHUV), CH-1011 Lausanne (Switzerland); Valley, J-F [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Verdun, F R [Institut Universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland)

    2005-06-07

    This work compares the detector performance and image quality of the new Kodak Min-R EV mammography screen-film system with the Fuji CR Profect detector and with other current mammography screen-film systems from Agfa, Fuji and Kodak. Basic image quality parameters (MTF, NPS, NEQ and DQE) were evaluated for a 28 kV Mo/Mo (HVL = 0.646 mm Al) beam using different mAs exposure settings. Compared with other screen-film systems, the new Kodak Min-R EV detector has the highest contrast and a low intrinsic noise level, giving better NEQ and DQE results, especially at high optical density. Thus, the properties of the new mammography film approach those of a fine mammography detector, especially at low frequency range. Screen-film systems provide the best resolution. The presampling MTF of the digital detector has a value of 15% at the Nyquist frequency and, due to the spread size of the laser beam, the use of a smaller pixel size would not permit a significant improvement of the detector resolution. The dual collection reading technology increases significantly the low frequency DQE of the Fuji CR system that can at present compete with the most efficient mammography screen-film systems.

  13. Performance comparison of digital microRNA profiling technologies applied on human breast cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Erik Knutsen

    Full Text Available MicroRNA profiling represents an important first-step in deducting individual RNA-based regulatory function in a cell, tissue, or at a specific developmental stage. Currently there are several different platforms to choose from in order to make the initial miRNA profiles. In this study we investigate recently developed digital microRNA high-throughput technologies. Four different platforms were compared including next generation SOLiD ligation sequencing and Illumina HiSeq sequencing, hybridization-based NanoString nCounter, and miRCURY locked nucleic acid RT-qPCR. For all four technologies, full microRNA profiles were generated from human cell lines that represent noninvasive and invasive tumorigenic breast cancer. This study reports the correlation between platforms, as well as a more extensive analysis of the accuracy and sensitivity of data generated when using different platforms and important consideration when verifying results by the use of additional technologies. We found all the platforms to be highly capable for microRNA analysis. Furthermore, the two NGS platforms and RT-qPCR all have equally high sensitivity, and the fold change accuracy is independent of individual miRNA concentration for NGS and RT-qPCR. Based on these findings we propose new guidelines and considerations when performing microRNA profiling.

  14. Generation and performance assessment of the global TanDEM-X digital elevation model

    Science.gov (United States)

    Rizzoli, Paola; Martone, Michele; Gonzalez, Carolina; Wecklich, Christopher; Borla Tridon, Daniela; Bräutigam, Benjamin; Bachmann, Markus; Schulze, Daniel; Fritz, Thomas; Huber, Martin; Wessel, Birgit; Krieger, Gerhard; Zink, Manfred; Moreira, Alberto

    2017-10-01

    The primary objective of the TanDEM-X mission is the generation of a global, consistent, and high-resolution digital elevation model (DEM) with unprecedented global accuracy. The goal is achieved by exploiting the interferometric capabilities of the two twin SAR satellites TerraSAR-X and TanDEM-X, which fly in a close orbit formation, acting as an X-band single-pass interferometer. Between December 2010 and early 2015 all land surfaces have been acquired at least twice, difficult terrain up to seven or eight times. The acquisition strategy, data processing, and DEM calibration and mosaicking have been systematically monitored and optimized throughout the entire mission duration, in order to fulfill the specification. The processing of all data has finally been completed in September 2016 and this paper reports on the final performance of the TanDEM-X global DEM and presents the acquisition and processing strategy which allowed to obtain the final DEM quality. The results confirm the outstanding global accuracy of the delivered product, which can be now utilized for both scientific and commercial applications.

  15. Simulation and Measurement of the Transmission Distortions of the Digital Television DVB-T/H Part 2: Hierarchical Modulation Performance

    Directory of Open Access Journals (Sweden)

    R. Stukavec

    2010-09-01

    Full Text Available The paper deals with the second part of results of the Czech Science Foundation research project that was aimed into the simulation and measurement of the transmission distortions of the digital terrestrial television according to DVB-T/H standards. In this part the hierarchical modulation performance characteristics and its simulation and laboratory measurements are presented. The paper deals with the hierarchical oriented COFDM modulator for the digital terrestrial television transmission and DVB-T/H standards and possible utilization of this technique in real broadcasting scenarios – fixed, portable and mobile digital TV, all in one TV channel. Impact of the hierarchical modulation on Modulation Error Rate from I/Q constellations and Bit Error Rates before and after Viterbi decoding in DVB-T/H signal decoding are evaluated and discussed.

  16. The performance and limitations of FPGA-based digital servos for atomic, molecular, and optical physics experiments.

    Science.gov (United States)

    Yu, Shi Jing; Fajeau, Emma; Liu, Lin Qiao; Jones, David J; Madison, Kirk W

    2018-02-01

    In this work, we address the advantages, limitations, and technical subtleties of employing field programmable gate array (FPGA)-based digital servos for high-bandwidth feedback control of lasers in atomic, molecular, and optical physics experiments. Specifically, we provide the results of benchmark performance tests in experimental setups including noise, bandwidth, and dynamic range for two digital servos built with low and mid-range priced FPGA development platforms. The digital servo results are compared to results obtained from a commercially available state-of-the-art analog servo using the same plant for control (intensity stabilization). The digital servos have feedback bandwidths of 2.5 MHz, limited by the total signal latency, and we demonstrate improvements beyond the transfer function offered by the analog servo including a three-pole filter and a two-pole filter with phase compensation to suppress resonances. We also discuss limitations of our FPGA-servo implementation and general considerations when designing and using digital servos.

  17. The performance and limitations of FPGA-based digital servos for atomic, molecular, and optical physics experiments

    Science.gov (United States)

    Yu, Shi Jing; Fajeau, Emma; Liu, Lin Qiao; Jones, David J.; Madison, Kirk W.

    2018-02-01

    In this work, we address the advantages, limitations, and technical subtleties of employing field programmable gate array (FPGA)-based digital servos for high-bandwidth feedback control of lasers in atomic, molecular, and optical physics experiments. Specifically, we provide the results of benchmark performance tests in experimental setups including noise, bandwidth, and dynamic range for two digital servos built with low and mid-range priced FPGA development platforms. The digital servo results are compared to results obtained from a commercially available state-of-the-art analog servo using the same plant for control (intensity stabilization). The digital servos have feedback bandwidths of 2.5 MHz, limited by the total signal latency, and we demonstrate improvements beyond the transfer function offered by the analog servo including a three-pole filter and a two-pole filter with phase compensation to suppress resonances. We also discuss limitations of our FPGA-servo implementation and general considerations when designing and using digital servos.

  18. Comparing the performance of various digital soil mapping approaches to map physical soil properties

    Science.gov (United States)

    Laborczi, Annamária; Takács, Katalin; Pásztor, László

    2015-04-01

    digital soil mapping methods and sets of ancillary variables for producing the most accurate spatial prediction of texture classes in a given area of interest. Both legacy and recently collected data on PSD were used as reference information. The predictor variable data set consisted of digital elevation model and its derivatives, lithology, land use maps as well as various bands and indices of satellite images. Two conceptionally different approaches can be applied in the mapping process. Textural classification can be realized after particle size data were spatially extended by proper geostatistical method. Alternatively, the textural classification is carried out first, followed by the spatial extension through suitable data mining method. According to the first approach, maps of sand, silt and clay percentage have been computed through regression kriging (RK). Since the three maps are compositional (their sum must be 100%), we applied Additive Log-Ratio (alr) transformation, instead of kriging them independently. Finally, the texture class map has been compiled according to the USDA categories from the three maps. Different combinations of reference and training soil data and auxiliary covariables resulted several different maps. On the basis of the other way, the PSD were classified firstly into the USDA categories, then the texture class maps were compiled directly by data mining methods (classification trees and random forests). The various results were compared to each other as well as to the RK maps. The performance of the different methods and data sets has been examined by testing the accuracy of the geostatistically computed and the directly classified results to assess the most predictive and accurate method. Acknowledgement: Our work was supported by the Hungarian National Scientific Research Foundation (OTKA, Grant No. K105167).

  19. The effects of sex, sexual orientation, and digit ratio (2D:4D) on mental rotation performance.

    Science.gov (United States)

    Peters, Michael; Manning, John T; Reimers, Stian

    2007-04-01

    In spite of the reduced level of experimental control, this large scale study brought some clarity into the relation between mental rotation task (MRT) performance and a number of variables where contradictory associations had previously been reported in the literature. Clear sex differences in MRT were observed for a sample of 134,317 men and 120,783 women, with men outperforming women. There were also MRT differences as a function of sexual orientation: heterosexual men performed better than homosexual men and homosexual women performed better than heterosexual women. Although bisexual men performed better than homosexual men but less well than heterosexual men, no significant differences were observed between bisexual and homosexual women. MRT performance in both men and women peaked in the 20-30 year range, and declined significantly and markedly thereafter. Both men and women showed a significant negative correlation between left and right digit finger ratio and MRT scores, such that individuals with smaller digit ratios (relatively longer ring finger than index finger) performed better than individuals with larger digit ratios.

  20. Sports Digitalization

    DEFF Research Database (Denmark)

    Xiao, Xiao; Hedman, Jonas; Tan, Felix Ter Chian

    2017-01-01

    evolution, as digital technologies are increasingly entrenched in a wide range of sporting activities and for applications beyond mere performance enhancement. Despite such trends, research on sports digitalization in the IS discipline is surprisingly still nascent. This paper aims at establishing...... a discourse on sports digitalization within the discipline. Toward this, we first provide an understanding of the institutional characteristics of the sports industry, establishing its theoretical importance and relevance in our discipline; second, we reveal the latest trends of digitalization in the sports...

  1. Comparative performance of modern digital mammography systems in a large breast screening program

    Energy Technology Data Exchange (ETDEWEB)

    Yaffe, Martin J., E-mail: martin.yaffe@sri.utoronto.ca; Bloomquist, Aili K.; Hunter, David M.; Mawdsley, Gordon E. [Physical Sciences Division, Sunnybrook Research Institute, Departments of Medical Biophysics and Medical Imaging, University of Toronto, Ontario M4N 3M5 (Canada); Chiarelli, Anna M. [Prevention and Cancer Control, Cancer Care Ontario, Dalla Lana School of Public Health, University of Toronto, Ontario M4N 3M5, Canada and Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Ontario M5G 1X3 (Canada); Muradali, Derek [Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Ontario M5G 1X3 (Canada); Mainprize, James G. [Physical Sciences Division, Sunnybrook Research Institute, Toronto, Ontario M4N 3M5 (Canada)

    2013-12-15

    Purpose: To compare physical measures pertaining to image quality among digital mammography systems utilized in a large breast screening program. To examine qualitatively differences in these measures and differences in clinical cancer detection rates between CR and DR among sites within that program. Methods: As part of the routine quality assurance program for screening, field measurements are made of several variables considered to correlate with the diagnostic quality of medical images including: modulation transfer function, noise equivalent quanta, d′ (an index of lesion detectability) and air kerma to allow estimation of mean glandular dose. In addition, images of the mammography accreditation phantom are evaluated. Results: It was found that overall there were marked differences between the performance measures of DR and CR mammography systems. In particular, the modulation transfer functions obtained with the DR systems were found to be higher, even for larger detector element sizes. Similarly, the noise equivalent quanta, d′, and the phantom scores were higher, while the failure rates associated with low signal-to-noise ratio and high dose were lower with DR. These results were consistent with previous findings in the authors’ program that the breast cancer detection rates at sites employing CR technology were, on average, 30.6% lower than those that used DR mammography. Conclusions: While the clinical study was not large enough to allow a statistically powered system-by-system assessment of cancer detection accuracy, the physical measures expressing spatial resolution, and signal-to-noise ratio are consistent with the published finding that sites employing CR systems had lower cancer detection rates than those using DR systems for screening mammography.

  2. Diagnostic performance of digital breast tomosynthesis with a wide scan angle compared to full-field digital mammography for the detection and characterization of microcalcifications

    International Nuclear Information System (INIS)

    Clauser, Paola; Nagl, Georg; Helbich, Thomas H.; Pinker-Domenig, Katja; Weber, Michael; Kapetas, Panagiotis; Bernathova, Maria; Baltzer, Pascal A.T.

    2016-01-01

    Highlights: • Wide scan-angle DBT alone shows a high detection rate for microcalcifications. • DBT and FFDM can characterize microcalcifications at a comparable level. • Characterization is influenced by reader and by lesion type (benign vs malignant). • DBT might be used as a stand-alone technique for the assessment of microcalcifications. - Abstract: Objectives: To assess the diagnostic performance of digital breast tomosynthesis (DBT), with a wide scan-angle, compared to full-field digital mammography (FFDM), for the detection and characterization of microcalcifications. Methods: IRB approval was obtained for this retrospective study. We selected 150 FFDM and DBT (50 benign and 50 malignant histologically verified microcalcifications, 50 cases classified as BI-RADS 1). Four radiologists evaluated, in separate sessions and blinded to patients’ history and histology, the presence of microcalcifications. Cases with microcalcifications were assessed for visibility, characteristics, and grade of suspicion using BI-RADS categories. Detection rate and diagnostic performance were calculated. Visibility, lesions’ characteristics and reading time were analysed. Results: Detection rate and visibility were good for both FFDM and DBT, without intra-reader differences (P = 0.510). Inter-reader differences were detected (P < 0.018). Only two lesions were not detected by any reader on either FFDM or DBT. Diagnostic performance with DBT was as good as that of FFDM, but a significant inter-reader difference was found (P = 0.041). High inter-reader variability in the use of the descriptors was found. Reading time for DBT was almost twice that for FFDM (44 and 25 s, respectively). Conclusion: Wide scan-angle DBT enabled the detection and characterization of microcalcifications with no significant differences from FFDM. Inter-reader variability was seen.

  3. Diagnostic performance of digital breast tomosynthesis with a wide scan angle compared to full-field digital mammography for the detection and characterization of microcalcifications

    Energy Technology Data Exchange (ETDEWEB)

    Clauser, Paola, E-mail: paola.clauser@meduniwien.ac.at [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Nagl, Georg [Department for Radiology and Interventional Radiology, Landesklinikum Horn, Spitalgasse 10, 3580 Horn (Austria); Helbich, Thomas H., E-mail: thomas.helbich@meduniwien.ac.at [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Pinker-Domenig, Katja [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Weber, Michael [Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria); Kapetas, Panagiotis; Bernathova, Maria; Baltzer, Pascal A.T. [Department of Biomedical Imaging and Image-Guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna (Austria)

    2016-12-15

    Highlights: • Wide scan-angle DBT alone shows a high detection rate for microcalcifications. • DBT and FFDM can characterize microcalcifications at a comparable level. • Characterization is influenced by reader and by lesion type (benign vs malignant). • DBT might be used as a stand-alone technique for the assessment of microcalcifications. - Abstract: Objectives: To assess the diagnostic performance of digital breast tomosynthesis (DBT), with a wide scan-angle, compared to full-field digital mammography (FFDM), for the detection and characterization of microcalcifications. Methods: IRB approval was obtained for this retrospective study. We selected 150 FFDM and DBT (50 benign and 50 malignant histologically verified microcalcifications, 50 cases classified as BI-RADS 1). Four radiologists evaluated, in separate sessions and blinded to patients’ history and histology, the presence of microcalcifications. Cases with microcalcifications were assessed for visibility, characteristics, and grade of suspicion using BI-RADS categories. Detection rate and diagnostic performance were calculated. Visibility, lesions’ characteristics and reading time were analysed. Results: Detection rate and visibility were good for both FFDM and DBT, without intra-reader differences (P = 0.510). Inter-reader differences were detected (P < 0.018). Only two lesions were not detected by any reader on either FFDM or DBT. Diagnostic performance with DBT was as good as that of FFDM, but a significant inter-reader difference was found (P = 0.041). High inter-reader variability in the use of the descriptors was found. Reading time for DBT was almost twice that for FFDM (44 and 25 s, respectively). Conclusion: Wide scan-angle DBT enabled the detection and characterization of microcalcifications with no significant differences from FFDM. Inter-reader variability was seen.

  4. A high performance cost-effective digital complex correlator for an X-band polarimetry survey.

    Science.gov (United States)

    Bergano, Miguel; Rocha, Armando; Cupido, Luís; Barbosa, Domingos; Villela, Thyrso; Boas, José Vilas; Rocha, Graça; Smoot, George F

    2016-01-01

    The detailed knowledge of the Milky Way radio emission is important to characterize galactic foregrounds masking extragalactic and cosmological signals. The update of the global sky models describing radio emissions over a very large spectral band requires high sensitivity experiments capable of observing large sky areas with long integration times. Here, we present the design of a new 10 GHz (X-band) polarimeter digital back-end to map the polarization components of the galactic synchrotron radiation field of the Northern Hemisphere sky. The design follows the digital processing trends in radio astronomy and implements a large bandwidth (1 GHz) digital complex cross-correlator to extract the Stokes parameters of the incoming synchrotron radiation field. The hardware constraints cover the implemented VLSI hardware description language code and the preliminary results. The implementation is based on the simultaneous digitized acquisition of the Cartesian components of the two linear receiver polarization channels. The design strategy involves a double data rate acquisition of the ADC interleaved parallel bus, and field programmable gate array device programming at the register transfer mode. The digital core of the back-end is capable of processing 32 Gbps and is built around an Altera field programmable gate array clocked at 250 MHz, 1 GSps analog to digital converters and a clock generator. The control of the field programmable gate array internal signal delays and a convenient use of its phase locked loops provide the timing requirements to achieve the target bandwidths and sensitivity. This solution is convenient for radio astronomy experiments requiring large bandwidth, high functionality, high volume availability and low cost. Of particular interest, this correlator was developed for the Galactic Emission Mapping project and is suitable for large sky area polarization continuum surveys. The solutions may also be adapted to be used at signal processing

  5. Persian randomized dichotic digits test: Development and dichotic listening performance in young adults

    Directory of Open Access Journals (Sweden)

    Mohammad Ebrahim Mahdavi

    2015-02-01

    Full Text Available Background and Aims: The dichotic listening subtest is an important component of the test battery for auditory processing assessment in both children and adults. A randomized dichotic digits test (RDDT was created to compensate for sensitivity weakness of double digits when detecting abnormal ear asymmetry during dichotic listening. The aim of this study was the development and  intial evaluation of the Persian randomized dichotic digits test.Method: Persian digits 1-10 (except for the bisyllabic digit, 4 uttered by a native Persian language speaker were recorded in a studio. After alignment of intensity and temporal characteristics of digit waveforms, lists 1 and 2 of the RDDT were reproduced. List 1 of the test was administered at 55 dBHL on 50 right-handed normal hearing individuals (with an equal sex ratio in the age group of 18-25 years and hearing thresholds of 15 dBHL or better in audiometric frequencies.Results: Mean (standard deviation of percent-correct score for right and left ears and right ear advantage of the subjects was 94.3 (5.3, 84.8 (7.7, and 9.5 (7.0 percent, respectively. Sixty percent of the subjects showed normal results and unilateral and bilateral deficits were seen in 24 percent and 16 percent, respectively, of studied individuals.Conclusion: It seems the Persian version of RDDT test is the same as the original test as it is able to test ear asymmerty, unilateral and bilateral deficits in dichotic listening.

  6. Comparison of the diagnostic performance of digital breast tomosynthesis and magnetic resonance imaging added to digital mammography in women with known breast cancers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Hwa; Chang, Jung Min; Moon, Woo Kyung [Seoul National University Hospital, Department of Radiology, 101 Daehangno, Jongno-gu, Seoul (Korea, Republic of); Moon, Hyeong-Gon [Seoul National University Hospital, Department of Surgery, Seoul (Korea, Republic of); Yi, Ann [Seoul National University Hospital, Department of Radiology, Gangnan Healthcare Center, Seoul (Korea, Republic of); Koo, Hye Ryoung [Hanyang University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Gweon, Hye Mi [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea, Republic of)

    2016-06-15

    To compare the diagnostic performance of digital breast tomosynthesis (DBT) and magnetic resonance imaging (MRI) added to mammography in women with known breast cancers. Three radiologists independently reviewed image sets of 172 patients with 184 cancers; mammography alone, DBT plus mammography and MRI plus mammography, and scored for cancer probability using the Breast Imaging Reporting and Data System (BI-RADS). Jack-knife alternative free-response receiver-operating characteristic (JAFROC), which allows diagnostic performance estimation using single lesion as a statistical unit in a cancer-only population, was used. Sensitivity and positive predictive value (PPV) were compared using the McNemar and Fisher-exact tests. The JAFROC figures of merit (FOMs) was lower in DBT plus mammography (0.937) than MRI plus mammography (0.978, P = 0.0006) but higher than mammography alone (0.900, P = 0.0013). The sensitivity was lower in DBT plus mammography (88.2 %) than MRI plus mammography (97.8 %) but higher than mammography alone (78.3 %, both P < 0.0001). The PPV was significantly higher in DBT plus mammography (93.3 %) than MRI plus mammography (89.6 %, P = 0.0282). DBT provided lower diagnostic performance than MRI as an adjunctive imaging to mammography. However, DBT had higher diagnostic performance than mammography and higher PPV than MRI. (orig.)

  7. Comparison of the diagnostic performance of digital breast tomosynthesis and magnetic resonance imaging added to digital mammography in women with known breast cancers

    International Nuclear Information System (INIS)

    Kim, Won Hwa; Chang, Jung Min; Moon, Woo Kyung; Moon, Hyeong-Gon; Yi, Ann; Koo, Hye Ryoung; Gweon, Hye Mi

    2016-01-01

    To compare the diagnostic performance of digital breast tomosynthesis (DBT) and magnetic resonance imaging (MRI) added to mammography in women with known breast cancers. Three radiologists independently reviewed image sets of 172 patients with 184 cancers; mammography alone, DBT plus mammography and MRI plus mammography, and scored for cancer probability using the Breast Imaging Reporting and Data System (BI-RADS). Jack-knife alternative free-response receiver-operating characteristic (JAFROC), which allows diagnostic performance estimation using single lesion as a statistical unit in a cancer-only population, was used. Sensitivity and positive predictive value (PPV) were compared using the McNemar and Fisher-exact tests. The JAFROC figures of merit (FOMs) was lower in DBT plus mammography (0.937) than MRI plus mammography (0.978, P = 0.0006) but higher than mammography alone (0.900, P = 0.0013). The sensitivity was lower in DBT plus mammography (88.2 %) than MRI plus mammography (97.8 %) but higher than mammography alone (78.3 %, both P < 0.0001). The PPV was significantly higher in DBT plus mammography (93.3 %) than MRI plus mammography (89.6 %, P = 0.0282). DBT provided lower diagnostic performance than MRI as an adjunctive imaging to mammography. However, DBT had higher diagnostic performance than mammography and higher PPV than MRI. (orig.)

  8. 75 FR 56873 - Digital Performance Right in Sound Recordings and Ephemeral Recordings

    Science.gov (United States)

    2010-09-17

    ... 14 (McCrady). The proposed minimum fee is fully recoupable against royalty fees owed and this feature... payments are pursuant to the royalty minimum fee that is the subject of this remand proceeding, 5/18/10 Tr... LIBRARY OF CONGRESS Copyright Royalty Board 37 CFR Part 380 [Docket No. 2005-1 CRB DTRA] Digital...

  9. Ultra-high performance, solid-state, autoradiographic image digitization and analysis system

    International Nuclear Information System (INIS)

    Lear, J.L.; Pratt, J.P.; Ackermann, R.F.; Plotnick, J.; Rumley, S.

    1990-01-01

    We developed a Macintosh II-based, charge-coupled device (CCD), image digitization and analysis system for high-speed, high-resolution quantification of autoradiographic image data. A linear CCD array with 3,500 elements was attached to a precision drive assembly and mounted behind a high-uniformity lens. The drive assembly was used to sweep the array perpendicularly to its axis so that an entire 20 x 25-cm autoradiographic image-containing film could be digitized into 256 gray levels at 50-microns resolution in less than 30 sec. The scanner was interfaced to a Macintosh II computer through a specially constructed NuBus circuit board and software was developed for autoradiographic data analysis. The system was evaluated by scanning individual films multiple times, then measuring the variability of the digital data between the different scans. Image data were found to be virtually noise free. The coefficient of variation averaged less than 1%, a value significantly exceeding the accuracy of both high-speed, low-resolution, video camera (VC) systems and low-speed, high-resolution, rotating drum densitometers (RDD). Thus, the CCD scanner-Macintosh computer analysis system offers the advantage over VC systems of the ability to digitize entire films containing many autoradiograms, but with much greater speed and accuracy than achievable with RDD scanners

  10. Children, Extracurricular Activities, and Digital Media: The Process of Displacement and School Performance

    Science.gov (United States)

    Mourgela, Vasiliki; Pacurar, Ecaterina

    2018-01-01

    This work, situated in the Greek sociocultural context, attempts to analyze the time spent by primary school students on digital and traditional extracurricular activities and the impact of these activities on the educational outcome. The first objective was to determine, by means of a quantitative survey, if the children as "digital…

  11. Performance Improvements and Congestion Reduction for Routing-based Synthesis for Digital Microfluidic Biochips

    DEFF Research Database (Denmark)

    Windh, Skyler; Phung, Calvin; Grissom, Daniel T.

    2017-01-01

    Routing-based synthesis for digital microfluidic biochips yields faster assay execution times compared to module-based synthesis. We show that routing-based synthesis can lead to deadlocks and livelocks in specific cases, and that dynamically detecting them and adjusting the probabilities...

  12. Performance of two different digital evaluation systems used for assessing pre-clinical dental students' prosthodontic technical skills.

    Science.gov (United States)

    Gratton, D G; Kwon, S R; Blanchette, D R; Aquilino, S A

    2017-11-01

    Proper integration of newly emerging digital assessment tools is a central issue in dental education in an effort to provide more accurate and objective feedback to students. The study examined how the outcomes of students' tooth preparation were correlated when evaluated using traditional faculty assessment and two types of digital assessment approaches. Specifically, incorporation of the Romexis Compare 2.0 (Compare) and Sirona prepCheck 1.1 (prepCheck) systems was evaluated. Additionally, satisfaction of students based on the type of software was evaluated through a survey. Students in a second-year pre-clinical prosthodontics course were allocated to either Compare (n = 42) or prepCheck (n = 37) systems. All students received conventional instruction and used their assigned digital system as an additional evaluation tool to aid in assessing their work. Examinations assessed crown preparations of the maxillary right central incisor (#8) and the mandibular left first molar (#19). All submissions were graded by faculty, Compare and prepCheck. Technical scores did not differ between student groups for any of the assessment approaches. Compare and prepCheck had modest, statistically significant correlations with faculty scores with a minimum correlation of 0.3944 (P = 0.0011) and strong, statistically significant correlations with each other with a minimum correlation of 0.8203 (P < 0.0001). A post-course student survey found that 55.26% of the students felt unfavourably about learning the digital evaluation protocols. A total of 62.31% felt favourably about the integration of these digital tools into the curriculum. Comparison of Compare and prepCheck showed no evidence of significant difference in students' prosthodontics technical performance and perception. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Recurso didático digital: complexidade da performance docente na produção (hipertextual

    Directory of Open Access Journals (Sweden)

    Juliana Sales Jacques

    2015-12-01

    O recurso didático digital, no âmbito do ensino-aprendizagem mediado por tecnologias em rede, constitui-se como mediador não humano que estabelece a relação entre o professor, o estudante e o saber a ser ensinado. A complexidade da performance docente no processo de transposição didática é elemento catalisador da complexidade da produção (hipertextual mediada por tecnologias em rede. Neste artigo, a partir de revisão de literatura, argumentamos sobre a produção de recurso didático digital à luz da concepção interacionista da linguagem. Nesse viés, dado que a linguagem é dotada de intencionalidade, o propósito de um recurso didático digital é, como ação inerente ao processo ensino-aprendizagem, transformar através da palavra escrita (linguagem verbal atrelada a todas as formas (sonora, visual, audiovisual, etc. que perpassam o universo da linguagem. Inferimos, como considerações finais, que a transformação pressupõe, na produção do texto digital (recurso didático, inovação no design pedagógico. E, diante disso, defendemos como inovação, além da integração hipermidiática, a produção aberta em rede através da autoria e coautoria. Tudo isso para que, dentro de uma vertente linguística interacionista, as diferentes formas de leitura potencializem além da produção, a negociação de sentidos do (hipertexto como recurso didático digital.

  14. Clinical performance evaluation of total protein measurement by digital refractometry and characterization of non-protein solute interferences

    Directory of Open Access Journals (Sweden)

    Joshua J.H. Hunsaker

    2016-12-01

    Full Text Available Objectives: Refractometric methods to measure total protein (TP in serum and plasma specimens have been replaced by automated biuret methods in virtually all routine clinical testing. A subset of laboratories, however, still report using refractometry to measure TP in conjunction with serum protein electrophoresis. The objective of this study was therefore to conduct a modern performance evaluation of a digital refractometer for TP measurement. Design and methods: Performance evaluation of a MISCO Palm Abbe™ digital refractometer was conducted through device familiarization, carryover, precision, accuracy, linearity, analytical sensitivity, analytical specificity, and reference interval verification. Comparison assays included a manual refractometer and an automated biuret assay. Results: Carryover risk was eliminated using a demineralized distilled water (ddH2O wash step. Precision studies demonstrated overall imprecision of 2.2% CV (low TP pool and 0.5% CV (high TP pool. Accuracy studies demonstrated correlation to both manual refractometry and the biuret method. An overall positive bias (+5.0% was observed versus the biuret method. On average, outlier specimens had an increased triglyceride concentration. Linearity was verified using mixed dilutions of: a low and high concentration patient pools, or b albumin-spiked ddH2O and high concentration patient pool. Decreased recovery was observed using ddH2O dilutions at low TP concentrations. Significant interference was detected at high concentrations of glucose (>267 mg/dL and triglycerides (>580 mg/dL. Current laboratory reference intervals for TP were verified. Conclusions: Performance characteristics of this digital refractometer were validated in a clinical laboratory setting. Biuret method remains the preferred assay for TP measurement in routine clinical analyses. Keywords: Refractometry, Digital refractometry, Total protein, Biuret, Serum protein electrophoresis, Monoclonal

  15. Effect of immediate feedback training on observer performance on a digital radiology workstation

    International Nuclear Information System (INIS)

    Mc Neill, K.M.; Maloney, K.; Elam, E.A.; Hillman, B.J.; Witzke, D.B.

    1990-01-01

    This paper reports on testing the hypothesis that training radiologists on a digital workstation would affect their efficiency and subjective acceptance of radiologic interpretation based on images shown on a cathode ray tub (CRT). Using a digital radiology workstation, six faculty radiologists and four senior residents read seven groups of six images each. In each group, three images were ranked as easy and three were ranked as difficult. All images were abnormal posteroanterior chest radiographs. On display of each image, the observer was asked which findings were present. After the observer listed his or her findings, the experimenter listed any findings not mentioned and pointed out any incorrect findings. The time to finding was recorded for each image, along with the number of corrections and missed findings. A postexperiment questionnaire was given to obtain subjective responses from the observers

  16. First-lactation performance in cows affected by digital dermatitis during the rearing period.

    Science.gov (United States)

    Gomez, A; Cook, N B; Socha, M T; Döpfer, D

    2015-07-01

    The long-term effects of prepartum digital dermatitis (DD) on first-lactation performance were evaluated in a cohort of 719 pregnant heifers. All heifers were followed for a period of 6 mo until calving and classified on the basis of the number of DD events diagnosed during this period as type I, type II, or type III (no DD, one DD event, and multiple DD events, respectively). Health during the initial 60d in milk (DIM), reproductive and hoof health outcomes, and milk production were compared between the 3 heifer type groups. All logistic and linear models were adjusted for age, height, and girth circumference at enrollment, and the type of trace mineral supplementation during the prepartum period. Overall, cows experiencing DD during the rearing period showed worse production and health outcomes compared with healthy heifers during the first lactation. The percentages of assisted calvings, stillbirths, culled before 60 DIM, and diseased cows during the fresh period were numerically higher in type III cows compared with type I cows. However, none of these differences were statistically significant at the 95% confidence level. Significantly lower conception at first service [odds ratio (OR)=0.55, 95% confidence interval (95% CI): 0.33, 0.89] and increased number of days open (mean=24d, 95% CI: 5.2, 43) were observed in type III cows compared with type I cows. In relation to hoof health, a significantly increased risk of DD during the first lactation was found in type II and III cows (OR=5.16, 95% CI: 3.23, 8.29; and OR=12.5, 95% CI: 7.52, 21.1, respectively), as well as earlier occurrence of DD following calving (OR=59d, 95% CI=20, 96, and OR=74d, 95% CI: 37, 109). Compared with type I cows, statistically significant milk production losses during the initial 305 DIM of 199 and 335kg were estimated in type II and III cows, respectively. This difference was due to a greater rate of production decline (less persistence) after peak yield. No differences in monthly fat

  17. Physical evaluation of prototype high-performance anti-scatter grids: potential for improved digital radiographic image quality

    International Nuclear Information System (INIS)

    Fetterly, Kenneth A; Schueler, Beth A

    2009-01-01

    Grid evaluation for a screen-film x-ray system has typically included independent measurement of the opposing contrast improvement factor and Bucky factor. Neither of these metrics, however, is appropriate when assessing grid performance in a digital imaging environment. For digital radiographic systems, the benefit of an anti-scatter grid is well characterized by the quantum signal-to-noise ratio improvement factor (K SNR ) provided by the grid. The purpose of this work was to measure K SNR of prototype grids designed for use with digital radiographic systems. The prototype grids had 5 mm tall lead septa, fiber interspace material, line rate N = 25 and 36 cm -1 and ratio r = 15 and 21, respectively. The primary and scatter transmission properties of the grids were measured, and K SNR was evaluated over a phantom thickness range of 10-50 cm. To provide a comparison, the K SNR of similarly constructed N44r15 and N80r15 grids is also reported. K SNR of the prototype grids ranged from 1.4 for the 10 cm phantom to 2.4 for the 50 cm phantom. For the thickest phantom, the SNR improvement factor of the prototype grids was 18-83% higher than that of the N44r15 and N80r15 grids, respectively. (note)

  18. Performance improvement of coherent free-space optical communication with quadrature phase-shift keying modulation using digital phase estimation.

    Science.gov (United States)

    Li, Xueliang; Geng, Tianwen; Ma, Shuang; Li, Yatian; Gao, Shijie; Wu, Zhiyong

    2017-06-01

    The performance of coherent free-space optical (CFSO) communication with phase modulation is limited by both phase fluctuations and intensity scintillations induced by atmospheric turbulence. To improve the system performance, one effective way is to use digital phase estimation. In this paper, a CFSO communication system with quadrature phase-shift keying modulation is studied. With consideration of the effects of log-normal amplitude fluctuations and Gauss phase fluctuations, a two-stage Mth power carrier phase estimation (CPE) scheme is proposed. The simulation results show that the phase noise can be suppressed greatly by this scheme, and the system symbol error rate performance with the two-stage Mth power CPE can be three orders lower than that of the single-stage Mth power CPE. Therefore, the two-stage CPE we proposed can contribute to the performance improvements of the CFSO communication system and has determinate guidance sense to its actual application.

  19. Performance of automatic exposure control of digital imaging systems in three big hospitals

    International Nuclear Information System (INIS)

    Avramova-Cholakova, S.; Dyakov, I.

    2012-01-01

    The digital imaging systems are quite new in Bulgaria and there is still no clear evidence between all the servicing companies how to set the automatic exposure control (AEC) of the systems. The aim of this work is to study the AEC settings of the digital imaging systems in three big hospitals, serviced by different engineering companies. This study included seven systems, one with digital radiography (DR) and the others with computed radiography (CR) detectors. The AEC settings were tested in terms of mean pixel value (MPV), air kerma at phantom exit and detector dose indicator (DDI) dependence from AEC chamber selection, tube voltage and phantom thickness. Relatively small variations in MPV up to 8 % were observed for 4 of the CR systems, usually with small variations in DDI as well (except for one system, for which up to 40 % difference in DDI consistency between chambers was found). Air kerma at phantom exit for these systems had bigger variations up to 29 %. The other CR systems had big variations in MPV up to 57 % with DDI variations up to 30 % while air kerma changes were not small - from 8 to 38 %. The DR system showed smaller variation in air kerma at phantom exit up to 8 % and bigger variations in MPV and DDI up to 20 % and 15 % respectively. There is no systematic approach in the AEC settings used in the 3 hospitals. Further investigation and collaboration with the servicing companies is needed aiming to establish the optimized selection of AEC calibration parameters in each case. (authors)

  20. Qubits and quantum Hamiltonian computing performances for operating a digital Boolean 1/2-adder

    Science.gov (United States)

    Dridi, Ghassen; Faizy Namarvar, Omid; Joachim, Christian

    2018-04-01

    Quantum Boolean (1 + 1) digits 1/2-adders are designed with 3 qubits for the quantum computing (Qubits) and 4 quantum states for the quantum Hamiltonian computing (QHC) approaches. Detailed analytical solutions are provided to analyse the time operation of those different 1/2-adder gates. QHC is more robust to noise than Qubits and requires about the same amount of energy for running its 1/2-adder logical operations. QHC is faster in time than Qubits but its logical output measurement takes longer.

  1. Operation and performance of a longitudinal feedback system using digital signal processing

    International Nuclear Information System (INIS)

    Teytelman, D.; Fox, J.; Hindi, H.

    1994-01-01

    A programmable longitudinal feedback system using a parallel array of AT ampersand T 1610 digital signal processors has been developed as a component of the PEP-II R ampersand D program. This system has been installed at the Advanced Light Source (LBL) and implements full speed bunch by bunch signal processing for storage rings with bunch spacing of 4ns. Open and closed loop results showing the action of the feedback system are presented, and the system is shown to damp coupled-bunch instabilities in the ALS. A unified PC-based software environment for the feedback system operation is also described

  2. High-performance digital triggering system for phase-controlled rectifiers

    International Nuclear Information System (INIS)

    Olsen, R.E.

    1983-01-01

    The larger power supplies used to power accelerator magnets are most commonly polyphase rectifiers using phase control. While this method is capable of handling impressive amounts of power, it suffers from one serious disadvantage, namely that of subharmonic ripple. Since the stability of the stored beam depends to a considerable extent on the regulation of the current in the bending magnets, subharmonic ripple, especially that of low frequency, can have a detrimental effect. At the NSLS, we have constructed a 12-pulse, phase control system using digital signal processing techniques that essentially eliminates subharmonic ripple

  3. Clinical performance evaluation of total protein measurement by digital refractometry and characterization of non-protein solute interferences.

    Science.gov (United States)

    Hunsaker, Joshua J H; Wyness, Sara P; Snow, Taylor M; Genzen, Jonathan R

    2016-12-01

    Refractometric methods to measure total protein (TP) in serum and plasma specimens have been replaced by automated biuret methods in virtually all routine clinical testing. A subset of laboratories, however, still report using refractometry to measure TP in conjunction with serum protein electrophoresis. The objective of this study was therefore to conduct a modern performance evaluation of a digital refractometer for TP measurement. Performance evaluation of a MISCO Palm Abbe™ digital refractometer was conducted through device familiarization, carryover, precision, accuracy, linearity, analytical sensitivity, analytical specificity, and reference interval verification. Comparison assays included a manual refractometer and an automated biuret assay. Carryover risk was eliminated using a demineralized distilled water (ddH 2 O) wash step. Precision studies demonstrated overall imprecision of 2.2% CV (low TP pool) and 0.5% CV (high TP pool). Accuracy studies demonstrated correlation to both manual refractometry and the biuret method. An overall positive bias (+5.0%) was observed versus the biuret method. On average, outlier specimens had an increased triglyceride concentration. Linearity was verified using mixed dilutions of: a) low and high concentration patient pools, or b) albumin-spiked ddH 2 O and high concentration patient pool. Decreased recovery was observed using ddH 2 O dilutions at low TP concentrations. Significant interference was detected at high concentrations of glucose (>267 mg/dL) and triglycerides (>580 mg/dL). Current laboratory reference intervals for TP were verified. Performance characteristics of this digital refractometer were validated in a clinical laboratory setting. Biuret method remains the preferred assay for TP measurement in routine clinical analyses.

  4. Backup control airstart performance on a digital electronic engine control-equipped F100-engine

    Science.gov (United States)

    Johnson, J. B.

    1984-01-01

    The air start capability of a backup control (BUC) was tested for a digital electronic engine control (DEEC) equipped F100 engine, which was installed in an F-15 aircraft. Two air start schedules were tested. Using the group 1 start schedule, based on a 40 sec timer, an air speed of 300 knots was required to ensure successful 40 and 25% BUC mode spooldown airstarts. If core rotor speed (N2) was less than 40% a stall would occur when the start bleed closed, 40 sec after initiation of the air start. All jet fuel starter (JFS) assisted air starts were successful with the group 1 start schedule. For the group 2 schedule, the time between pressurization and start bleed closure ranged between 50 sec and 72 sec. Idle rps was lower than the desired 65% for air starts at higher altitudes and lower air speeds.

  5. Image Gently: Challenges for radiologic technologists when performing digital radiography in children

    International Nuclear Information System (INIS)

    Goske, Marilyn J.; Smith, Susan N.; Charkot, Ellen; Herrmann, Tracy; John, Susan D.; Mills, Thalia T.; Morrison, Gregory

    2011-01-01

    The development of digital radiography (DR) has provided numerous benefits for pediatric imaging, including the ability to post-process images and to make images immediately available for access by care providers. However, DR presents several significant challenges for the radiologic technologists who are responsible for operating the equipment and producing high-quality images in children. This paper discusses those challenges, including lack of standardization among vendors, particularly with regard to the exposure indicator; lack of pediatric-specific educational materials and pediatric techniques; the need for manual technique instead of the use of automatic exposure control in smaller children; and complications related to field size, collimation and shielding in small children. Specific actions and design modifications that might facilitate the effective management of these challenges will be also described. The implementation of measures to promote the production of optimal images while minimizing radiation exposure requires cooperation and communication among imaging professionals, manufacturers and regulatory agencies. (orig.)

  6. Operation and performance of a longitudinal damping system using parallel digital signal processing

    International Nuclear Information System (INIS)

    Fox, J.D.; Hindi, H.; Linscott, I.

    1994-06-01

    A programmable longitudinal feedback system based on four AT ampersand T 1610 digital signal processors has been developed as a component of the PEP-II R ampersand D program. This Longitudinal Quick Prototype is a proof of concept for the PEP-II system and implements full speed bunch-by-bunch signal processing for storage rings with bunch spacings of 4 ns. The design implements, via software, a general purpose feedback controller which allows the system to be operated at several accelerator facilities. The system configuration used for tests at the LBL Advanced Light Source is described. Open and closed loop results showing the detection and calculation of feedback signals from bunch motion are presented, and the system is shown to damp coupled-bunch instabilities in the ALS. Use of the system for accelerator diagnostics is illustrated via measurement of injection transients and analysis of open loop bunch motion

  7. Free software for performing physical analysis of systems for digital radiography and mammography

    Energy Technology Data Exchange (ETDEWEB)

    Donini, Bruno; Lanconelli, Nico, E-mail: nico.lanconelli@unibo.it [Alma Mater Studiorum, Department of Physics and Astronomy, University of Bologna, Bologna 40127 (Italy); Rivetti, Stefano [Fisica Medica, Ospedale di Sassuolo S.p.A., Sassuolo 41049 (Italy); Bertolini, Marco [Medical Physics Unit, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, Reggio Emilia 42123 (Italy)

    2014-05-15

    Purpose: In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. Methods: The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. Results: The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. Conclusions: This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online ( http://www.medphys.it/downloads.htm ). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement.

  8. Free software for performing physical analysis of systems for digital radiography and mammography.

    Science.gov (United States)

    Donini, Bruno; Rivetti, Stefano; Lanconelli, Nico; Bertolini, Marco

    2014-05-01

    In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online (www.medphys.it/downloads.htm). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement.

  9. Blurred digital mammography images: an analysis of technical recall and observer detection performance.

    Science.gov (United States)

    Ma, Wang Kei; Borgen, Rita; Kelly, Judith; Millington, Sara; Hilton, Beverley; Aspin, Rob; Lança, Carla; Hogg, Peter

    2017-03-01

    Blurred images in full-field digital mammography are a problem in the UK Breast Screening Programme. Technical recalls may be due to blurring not being seen on lower resolution monitors used for review. This study assesses the visual detection of blurring on a 2.3-MP monitor and a 5-MP report grade monitor and proposes an observer standard for the visual detection of blurring on a 5-MP reporting grade monitor. 28 observers assessed 120 images for blurring; 20 images had no blurring present, whereas 100 images had blurring imposed through mathematical simulation at 0.2, 0.4, 0.6, 0.8 and 1.0 mm levels of motion. Technical recall rate for both monitors and angular size at each level of motion were calculated. χ 2 tests were used to test whether significant differences in blurring detection existed between 2.3- and 5-MP monitors. The technical recall rate for 2.3- and 5-MP monitors are 20.3% and 9.1%, respectively. The angular size for 0.2- to 1-mm motion varied from 55 to 275 arc s. The minimum amount of motion for visual detection of blurring in this study is 0.4 mm. For 0.2-mm simulated motion, there was no significant difference [χ 2 (1, N = 1095) = 1.61, p = 0.20] in blurring detection between the 2.3- and 5-MP monitors. According to this study, monitors ≤2.3 MP are not suitable for technical review of full-field digital mammography images for the detection of blur. Advances in knowledge: This research proposes the first observer standard for the visual detection of blurring.

  10. Free software for performing physical analysis of systems for digital radiography and mammography

    International Nuclear Information System (INIS)

    Donini, Bruno; Lanconelli, Nico; Rivetti, Stefano; Bertolini, Marco

    2014-01-01

    Purpose: In this paper, the authors present a free software for assisting users in achieving the physical characterization of x-ray digital systems and image quality checks. Methods: The program was developed as a plugin of a well-known public-domain suite ImageJ. The software can assist users in calculating various physical parameters such as the response curve (also termed signal transfer property), modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). It also includes the computation of some image quality checks: defective pixel analysis, uniformity, dark analysis, and lag. Results: The software was made available in 2009 and has been used during the last couple of years by many users who gave us valuable feedback for improving its usability. It was tested for achieving the physical characterization of several clinical systems for digital radiography and mammography. Various published papers made use of the outcomes of the plugin. Conclusions: This software is potentially beneficial to a variety of users: physicists working in hospitals, staff working in radiological departments, such as medical physicists, physicians, engineers. The plugin, together with a brief user manual, are freely available and can be found online ( http://www.medphys.it/downloads.htm ). With our plugin users can estimate all three most important parameters used for physical characterization (MTF, NPS, and also DQE). The plugin can run on any operating system equipped with ImageJ suite. The authors validated the software by comparing MTF and NPS curves on a common set of images with those obtained with other dedicated programs, achieving a very good agreement

  11. Quantitative performance of E-Scribe warehouse in detecting quality issues with digital annotated ECG data from healthy subjects.

    Science.gov (United States)

    Sarapa, Nenad; Mortara, Justin L; Brown, Barry D; Isola, Lamberto; Badilini, Fabio

    2008-05-01

    The US Food and Drug Administration recommends submission of digital electrocardiograms in the standard HL7 XML format into the electrocardiogram warehouse to support preapproval review of new drug applications. The Food and Drug Administration scrutinizes electrocardiogram quality by viewing the annotated waveforms and scoring electrocardiogram quality by the warehouse algorithms. Part of the Food and Drug Administration warehouse is commercially available to sponsors as the E-Scribe Warehouse. The authors tested the performance of E-Scribe Warehouse algorithms by quantifying electrocardiogram acquisition quality, adherence to QT annotation protocol, and T-wave signal strength in 2 data sets: "reference" (104 digital electrocardiograms from a phase I study with sotalol in 26 healthy subjects with QT annotations by computer-assisted manual adjustment) and "test" (the same electrocardiograms with an intentionally introduced predefined number of quality issues). The E-Scribe Warehouse correctly detected differences between the 2 sets expected from the number and pattern of errors in the "test" set (except for 1 subject with QT misannotated in different leads of serial electrocardiograms) and confirmed the absence of differences where none was expected. E-Scribe Warehouse scores below the threshold value identified individual electrocardiograms with questionable T-wave signal strength. The E-Scribe Warehouse showed satisfactory performance in detecting electrocardiogram quality issues that may impair reliability of QTc assessment in clinical trials in healthy subjects.

  12. Intra-system reliability of SICS: video-tracking system (Digital.Stadium®) for performance analysis in football.

    Science.gov (United States)

    Beato, Marco; Jamil, Mikael

    2017-05-09

    The correct evaluation of external load parameters is a key factor in professional football. The instrumentations usually utilised to quantify the external load parameters during official matches are Video-Tracking Systems (VTS). VTS is a technology that records two- dimensional position data (x and y) at high sampling rates (over 25 Hz). The aim of this study was to evaluate the intra-system reliability of Digital.Stadium® VTS. 28 professional male football players taking part in the Italian Serie A (age 24 ± 6 years, body mass 79.5 ± 7.8 kg, stature 1.83 ± 0.05 m) during the 2015/16 season were enrolled in this study (Team A and Team B). Video-analysis was done during an official match and data analysis was performed immediately after the game ended and then replicated a week later. This study reported a near perfect relationship between the initial analysis (analysis 1) and the replicated analysis undertaken a week later (analysis 2). R2 coefficients were highly significant for each of the performance parameters, p power of 9.65 ± 1.64 w kg-1 and 9.58 ± 1.61 w kg-1, in analysis 1 and analysis 2, respectively. The findings reported in this study underlined that all data reported by Digital.Stadium® VTS showed high levels of absolute and relative reliability.

  13. Games-to-teach or games-to-learn unlocking the power of digital game-based learning through performance

    CERN Document Server

    Chee, Yam San

    2016-01-01

    The book presents a critical evaluation of current approaches related to the use of digital games in education. The author identifies two competing paradigms: that of games-to-teach and games-to-learn. Arguing in favor of the latter, the author advances the case for approaching game-based learning through the theoretical lens of performance, rooted in play and dialog, to unlock the power of digital games for 21st century learning. Drawing upon the author’s research, three concrete exemplars of game-based learning curricula are described and discussed. The challenge of advancing game-based learning in education is addressed in the context of school reform. Finally, future prospects of and educational opportunities for game-based learning are articulated. Readers of the book will find the explication of performance theory applied to game-based learning especially interesting. This work constitutes the author’s original theorization. Readers will derive four main benefits: (1) an explication of the differenc...

  14. Effects of magnification and zooming on depth perception in digital stereomammography: an observer performance study

    International Nuclear Information System (INIS)

    Chan Heangping; Goodsitt, Mitchell M; Hadjiiski, Lubomir M; Bailey, Janet E; Klein, Katherine; Darner, Katie L; Sahiner, Berkman

    2003-01-01

    We are evaluating the application of stereoscopic imaging to digital mammography. In the current study, we investigated the effects of magnification and zooming on depth perception. A modular phantom was designed which contained six layers of 1-mm-thick Lexan plates, each spaced 1 mm apart. Eight to nine small, thin nylon fibrils were pasted on each plate in horizontal or vertical orientations such that they formed 25 crossing fibril pairs in a projected image. The depth separation between each fibril pair ranged from 2 to 10 mm. A change in the order of the Lexan plates changed the depth separation of the two fibrils in a pair. Stereoscopic image pairs of the phantom were acquired with a GE full-field digital mammography system. Three different phantom configurations were imaged. All images were obtained using a Rh target/Rh filter spectrum at 30 kVp tube potential and a ±3 degrees stereo shift angle. Images were acquired in both contact and 1.8X magnification geometry and an exposure range of 4 to 63 mAs was employed. The images were displayed on a Barco monitor driven by a Metheus stereo graphics board and viewed with LCD stereo glasses. Five observers participated in the study. Each observer visually judged whether the vertical fibril was in front of or behind the horizontal fibril in each fibril pair. It was found that the accuracy of depth discrimination increased with increasing fibril depth separation and x-ray exposure. The accuracy was not improved by electronic display zooming of the contact stereo images by 2X. Under conditions of high noise (low mAs) and small depth separation between the fibrils, the observers' depth discrimination ability was significantly better in stereo images acquired with geometric magnification than in images acquired with a contact technique and displayed with or without zooming. Under our experimental conditions, a 2 mm depth discrimination was achieved with over 60% accuracy on contact images with and without zooming, and

  15. A method to test the reproducibility and to improve performance of computer-aided detection schemes for digitized mammograms

    International Nuclear Information System (INIS)

    Zheng Bin; Gur, David; Good, Walter F.; Hardesty, Lara A.

    2004-01-01

    The purpose of this study is to develop a new method for assessment of the reproducibility of computer-aided detection (CAD) schemes for digitized mammograms and to evaluate the possibility of using the implemented approach for improving CAD performance. Two thousand digitized mammograms (representing 500 cases) with 300 depicted verified masses were selected in the study. Series of images were generated for each digitized image by resampling after a series of slight image rotations. A CAD scheme developed in our laboratory was applied to all images to detect suspicious mass regions. We evaluated the reproducibility of the scheme using the detection sensitivity and false-positive rates for the original and resampled images. We also explored the possibility of improving CAD performance using three methods of combining results from the original and resampled images, including simple grouping, averaging output scores, and averaging output scores after grouping. The CAD scheme generated a detection score (from 0 to 1) for each identified suspicious region. A region with a detection score >0.5 was considered as positive. The CAD scheme detected 238 masses (79.3% case-based sensitivity) and identified 1093 false-positive regions (average 0.55 per image) in the original image dataset. In eleven repeated tests using original and ten sets of rotated and resampled images, the scheme detected a maximum of 271 masses and identified as many as 2359 false-positive regions. Two hundred and eighteen masses (80.4%) and 618 false-positive regions (26.2%) were detected in all 11 sets of images. Combining detection results improved reproducibility and the overall CAD performance. In the range of an average false-positive detection rate between 0.5 and 1 per image, the sensitivity of the scheme could be increased approximately 5% after averaging the scores of the regions detected in at least four images. At low false-positive rate (e.g., ≤average 0.3 per image), the grouping method

  16. The European FAZIA initiative: a high-performance digital telescope array for heavy-ion studies

    International Nuclear Information System (INIS)

    Casini, G.; Barlini, S.; Pasquali, G.; Pastore, G.; Bini, M.; Carboni, S.; Olmi, A.; Piantelli, S.; Poggi, G.; Stefanini, A.; Valdre, S.; Bonnet, E.; Chbihi, A.; Frankland, J.D.; Gruyer, D.; Marini, P.; Borderie, B.; Edelbruck, P.; Rivet, M.F.; Salomon, F.; Bougault, R.; Le Neindre, N.; Lopez, O.; Parlog, M.; Vient, E.; Bruno, M.; Guerzoni, M.; Morelli, L.; Cinausero, M.; Gramegna, F.; Degerlier, M.; Kordjasz, A.; Twarog, T.; Kozik, T.; Marchi, T.; Ordine, A.; Rosato, E.; Spadaccini, G.; Vigilante, M.

    2014-01-01

    A modular array of 192 Si-Si-CsI(Tl) telescopes is under construction by the european FAZIA collaboration for charged product identification in heavy-ion studies. Thanks to an intense development phase, the ion identification capability of such modules has been improved both adopting specific solutions for the detectors and using fast digital electronics channels featuring high resolution. The silicons have been cut to present almost random orientation and have uniform doping homogeneity. To improve pulse shape analysis (PSA), they are reverse mounted in the telescopes. Full charge separation has been obtained up to over Z=54 also for ions stopping in the first silicon layer via PSA, with a threshold of 2.5 MeV/u for Carbon (Tin) ions. Isotopes are separated up to the iron region by the ΔE - E method for ions stopped in second silicon or in the CsI crystal. For slower particles, the PSA allows for isotopic resolution up to Z ∼ 14 with thresholds corresponding to ∼ 50 μm of (fully depleted) silicon detector. Preliminary results for partially depleted detectors indicate a strong improvement of mass separation with respect to the full depletion case at the cost of somewhat higher thresholds

  17. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    International Nuclear Information System (INIS)

    Annovazzi, A.; Amendolia, S.R.; Bigongiari, A.; Bisogni, M.G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Colombo, F.; Delogu, P.; Fantacci, M.E.; Gilberti, A.; Lanzieri, C.; Lavagna, S.; Novelli, M.; Passuello, G.; Paternoster, G.; Pieracci, M.; Poletti, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Testa, A.; Venturelli, L.

    2007-01-01

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm 2 therefore to cover the typical irradiation field used in mammography (18x24 cm 2 ), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma 'La Sapienza', Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%

  18. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    Science.gov (United States)

    Annovazzi, A.; Amendolia, S. R.; Bigongiari, A.; Bisogni, M. G.; Catarsi, F.; Cesqui, F.; Cetronio, A.; Colombo, F.; Delogu, P.; Fantacci, M. E.; Gilberti, A.; Lanzieri, C.; Lavagna, S.; Novelli, M.; Passuello, G.; Paternoster, G.; Pieracci, M.; Poletti, M.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Testa, A.; Venturelli, L.

    2007-06-01

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm 2 therefore to cover the typical irradiation field used in mammography (18×24 cm 2), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma "La Sapienza", Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%.

  19. Digital broadcasting

    International Nuclear Information System (INIS)

    Park, Ji Hyeong

    1999-06-01

    This book contains twelve chapters, which deals with digitization of broadcast signal such as digital open, digitization of video signal and sound signal digitization of broadcasting equipment like DTPP and digital VTR, digitization of equipment to transmit such as digital STL, digital FPU and digital SNG, digitization of transmit about digital TV transmit and radio transmit, digital broadcasting system on necessity and advantage, digital broadcasting system abroad and Korea, digital broadcasting of outline, advantage of digital TV, ripple effect of digital broadcasting and consideration of digital broadcasting, ground wave digital broadcasting of DVB-T in Europe DTV in U.S.A and ISDB-T in Japan, HDTV broadcasting, satellite broadcasting, digital TV broadcasting in Korea, digital radio broadcasting and new broadcasting service.

  20. Digitally controlled high-performance dc SQUID readout electronics for a 304-channel vector magnetometer

    Science.gov (United States)

    Bechstein, S.; Petsche, F.; Scheiner, M.; Drung, D.; Thiel, F.; Schnabel, A.; Schurig, Th

    2006-06-01

    Recently, we have developed a family of dc superconducting quantum interference device (SQUID) readout electronics for several applications. These electronics comprise a low-noise preamplifier followed by an integrator, and an analog SQUID bias circuit. A highly-compact low-power version with a flux-locked loop bandwidth of 0.3 MHz and a white noise level of 1 nV/√Hz was specially designed for a 304-channel low-Tc dc SQUID vector magnetometer, intended to operate in the new Berlin Magnetically Shielded Room (BMSR-2). In order to minimize the space needed to mount the electronics on top of the dewar and to minimize the power consumption, we have integrated four electronics channels on one 3 cm × 10 cm sized board. Furthermore we embedded the analog components of these four channels into a digitally controlled system including an in-system programmable microcontroller. Four of these integrated boards were combined to one module with a size of 4 cm × 4 cm × 16 cm. 19 of these modules were implemented, resulting in a total power consumption of about 61 W. To initialize the 304 channels and to service the system we have developed software tools running on a laptop computer. By means of these software tools the microcontrollers are fed with all required data such as the working points, the characteristic parameters of the sensors (noise, voltage swing), or the sensor position inside of the vector magnetometer system. In this paper, the developed electronics including the software tools are described, and first results are presented.

  1. A GaAs pixel detectors-based digital mammographic system: Performances and imaging tests results

    Energy Technology Data Exchange (ETDEWEB)

    Annovazzi, A. [LABEN S.p.A., Vimodrone-Milan (Italy); Amendolia, S.R. [Str. Dip. di Matematica e Fisica dell' Universita, Sassari and Sezione I.N.F.N., Pisa (Italy); Bigongiari, A. [CAEN S.p.A., Viareggio-Lucca (Italy); Bisogni, M.G. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Catarsi, F. [CAEN S.p.A., Viareggio-Lucca (Italy); Cesqui, F. [AMS S.p.A, Rome (Italy); Cetronio, A. [AMS S.p.A, Rome (Italy); Colombo, F. [LABEN S.p.A., Vimodrone-Milan (Italy); Delogu, P. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Fantacci, M.E. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Gilberti, A. [LABEN S.p.A., Vimodrone-Milan (Italy); Lanzieri, C. [AMS S.p.A, Rome (Italy); Lavagna, S. [AMS S.p.A, Rome (Italy); Novelli, M. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Passuello, G. [CAEN S.p.A., Viareggio-Lucca (Italy); Paternoster, G. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Pieracci, M. [CAEN S.p.A., Viareggio-Lucca (Italy); Poletti, M. [LABEN S.p.A., Vimodrone-Milan (Italy); Quattrocchi, M. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Rosso, V. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy); Stefanini, A. [Dipartimento di Fisica ' E. Fermi' dell' Universita and Sezione I.N.F.N., Pisa (Italy)]. E-mail: arnaldo.stefanini@pi.infn.it; Testa, A. [CAEN S.p.A., Viareggio-Lucca (Italy); Venturelli, L. [AMS S.p.A, Rome (Italy)

    2007-06-11

    The prototype presented in this paper is based on GaAs pixel detectors read-out by the PCC/MEDIPIX I circuit. The active area of a sensor is about 1 cm{sup 2} therefore to cover the typical irradiation field used in mammography (18x24 cm{sup 2}), 18 GaAs detection units have been organized in two staggered rows of nine chips each and moved by a stepper motor in the orthogonal direction. The system is integrated in a mammographic equipment which comprehends the X-ray tube, the bias and data acquisition systems and the PC-based control system. The prototype has been developed in the framework of the Integrated Mammographic Imaging (IMI) project, an industrial research activity aiming to develop innovative instrumentation for morphologic and functional imaging. The project has been supported by the Italian Ministry of Education, University and Research (MIUR) and by five Italian High Tech companies, Alenia Marconi Systems (AMS), CAEN, Gilardoni, LABEN and Poli.Hi.Tech., in collaboration with the universities of Ferrara, Roma 'La Sapienza', Pisa and the Istituto Nazionale di Fisica Nucleare (INFN). In this paper, we report on the electrical characterization and the first imaging test results of the digital mammographic system. To assess the imaging capability of such a detector we have built a phantom, which simulates the breast tissue with malignancies. The radiographs of the phantom, obtained by delivering an entrance dose of 4.8 mGy, have shown particulars with a measured contrast below 1%.

  2. Modeling indirect detectors for performance optimization of a digital mammographic detector for dual energy applications

    International Nuclear Information System (INIS)

    Martini, N; Koukou, V; Sotiropoulou, P; Nikiforidis, G; Kalyvas, N; Michail, C; Valais, I; Kandarakis, I; Fountos, G; Bakas, A

    2015-01-01

    Dual Energy imaging is a promising method for visualizing masses and microcalcifications in digital mammography. The advent of two X-ray energies (low and high) requires a suitable detector. The scope of this work is to determine optimum detector parameters for dual energy applications. The detector was modeled through the linear cascaded (LCS) theory. It was assumed that a phosphor material was coupled to a CMOS photodetector (indirect detection). The pixel size was 22.5 μm. The phosphor thickness was allowed to vary between 20mg/cm 2 and 160mg/cm 2 The phosphor materials examined where Gd 2 O 2 S:Tb and Gd 2 O 2 S:Eu. Two Tungsten (W) anode X-ray spectra at 35 kV (filtered with 100 μm Palladium (Pd)) and 70 kV (filtered with 800 pm Ytterbium (Yb)), corresponding to low and high energy respectively, were considered to be incident on the detector. For each combination the contrast- to-noise ratio (CNR) and the detector optical gain (DOG), showing the sensitivity of the detector, were calculated. The 40 mg/cm 2 and 70 mg/cm 2 Gd 2 O 2 S:Tb exhibited the higher DOG values for the low and high energy correspondingly. Higher CNR between microcalcification and mammary gland exhibited the 70mg/cm 2 and the 100mg/cm 2 Gd 2 O 2 S:Tb for the low and the high energy correspondingly

  3. Digitally controlled high-performance dc SQUID readout electronics for a 304-channel vector magnetometer

    International Nuclear Information System (INIS)

    Bechstein, S; Petsche, F; Scheiner, M; Drung, D; Thiel, F; Schnabel, A; Schurig, Th

    2006-01-01

    Recently, we have developed a family of dc superconducting quantum interference device (SQUID) readout electronics for several applications. These electronics comprise a low-noise preamplifier followed by an integrator, and an analog SQUID bias circuit. A highly-compact low-power version with a flux-locked loop bandwidth of 0.3 MHz and a white noise level of 1 nV/√Hz was specially designed for a 304-channel low-T c dc SQUID vector magnetometer, intended to operate in the new Berlin Magnetically Shielded Room (BMSR-2). In order to minimize the space needed to mount the electronics on top of the dewar and to minimize the power consumption, we have integrated four electronics channels on one 3 cm x 10 cm sized board. Furthermore we embedded the analog components of these four channels into a digitally controlled system including an in-system programmable microcontroller. Four of these integrated boards were combined to one module with a size of 4 cm x 4 cm x 16 cm. 19 of these modules were implemented, resulting in a total power consumption of about 61 W. To initialize the 304 channels and to service the system we have developed software tools running on a laptop computer. By means of these software tools the microcontrollers are fed with all required data such as the working points, the characteristic parameters of the sensors (noise, voltage swing), or the sensor position inside of the vector magnetometer system. In this paper, the developed electronics including the software tools are described, and first results are presented

  4. Digitally controlled high-performance dc SQUID readout electronics for a 304-channel vector magnetometer

    Energy Technology Data Exchange (ETDEWEB)

    Bechstein, S [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Petsche, F [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Scheiner, M [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Drung, D [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Thiel, F [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Schnabel, A [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany); Schurig, Th [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)

    2006-06-01

    Recently, we have developed a family of dc superconducting quantum interference device (SQUID) readout electronics for several applications. These electronics comprise a low-noise preamplifier followed by an integrator, and an analog SQUID bias circuit. A highly-compact low-power version with a flux-locked loop bandwidth of 0.3 MHz and a white noise level of 1 nV/{radical}Hz was specially designed for a 304-channel low-T{sub c} dc SQUID vector magnetometer, intended to operate in the new Berlin Magnetically Shielded Room (BMSR-2). In order to minimize the space needed to mount the electronics on top of the dewar and to minimize the power consumption, we have integrated four electronics channels on one 3 cm x 10 cm sized board. Furthermore we embedded the analog components of these four channels into a digitally controlled system including an in-system programmable microcontroller. Four of these integrated boards were combined to one module with a size of 4 cm x 4 cm x 16 cm. 19 of these modules were implemented, resulting in a total power consumption of about 61 W. To initialize the 304 channels and to service the system we have developed software tools running on a laptop computer. By means of these software tools the microcontrollers are fed with all required data such as the working points, the characteristic parameters of the sensors (noise, voltage swing), or the sensor position inside of the vector magnetometer system. In this paper, the developed electronics including the software tools are described, and first results are presented.

  5. Amorphous Zinc Oxide Integrated Wavy Channel Thin Film Transistor Based High Performance Digital Circuits

    KAUST Repository

    Hanna, Amir; Hussain, Aftab M.; Omran, Hesham; Alshareef, Sarah; Salama, Khaled N.; Hussain, Muhammad Mustafa

    2015-01-01

    High performance thin film transistor (TFT) can be a great driving force for display, sensor/actuator, integrated electronics, and distributed computation for Internet of Everything applications. While semiconducting oxides like zinc oxide (Zn

  6. Quantifying the performance of automated GIS-based geomorphological approaches for riparian zone delineation using digital elevation models

    Directory of Open Access Journals (Sweden)

    D. Fernández

    2012-10-01

    Full Text Available Riparian zone delineation is a central issue for managing rivers and adjacent areas; however, criteria used to delineate them are still under debate. The area inundated by a 50-yr flood has been indicated as an optimal hydrological descriptor for riparian areas. This detailed hydrological information is usually only available for populated areas at risk of flooding. In this work we created several floodplain surfaces by means of two different GIS-based geomorphological approaches using digital elevation models (DEMs, in an attempt to find hydrologically meaningful potential riparian zones for river networks at the river basin scale. Objective quantification of the performance of the two geomorphologic models is provided by analysing coinciding and exceeding areas with respect to the 50-yr flood surface in different river geomorphological types.

  7. Comparing the Performance of Commonly Available Digital Elevation Models in GIS-based Flood Simulation

    Science.gov (United States)

    Ybanez, R. L.; Lagmay, A. M. A.; David, C. P.

    2016-12-01

    With climatological hazards increasing globally, the Philippines is listed as one of the most vulnerable countries in the world due to its location in the Western Pacific. Flood hazards mapping and modelling is one of the responses by local government and research institutions to help prepare for and mitigate the effects of flood hazards that constantly threaten towns and cities in floodplains during the 6-month rainy season. Available digital elevation maps, which serve as the most important dataset used in 2D flood modelling, are limited in the Philippines and testing is needed to determine which of the few would work best for flood hazards mapping and modelling. Two-dimensional GIS-based flood modelling with the flood-routing software FLO-2D was conducted using three different available DEMs from the ASTER GDEM, the SRTM GDEM, and the locally available IfSAR DTM. All other parameters kept uniform, such as resolution, soil parameters, rainfall amount, and surface roughness, the three models were run over a 129-sq. kilometer watershed with only the basemap varying. The output flood hazard maps were compared on the basis of their flood distribution, extent, and depth. The ASTER and SRTM GDEMs contained too much error and noise which manifested as dissipated and dissolved hazard areas in the lower watershed where clearly delineated flood hazards should be present. Noise on the two datasets are clearly visible as erratic mounds in the floodplain. The dataset which produced the only feasible flood hazard map is the IfSAR DTM which delineates flood hazard areas clearly and properly. Despite the use of ASTER and SRTM with their published resolution and accuracy, their use in GIS-based flood modelling would be unreliable. Although not as accessible, only IfSAR or better datasets should be used for creating secondary products from these base DEM datasets. For developing countries which are most prone to hazards, but with limited choices for basemaps used in hazards

  8. The effect of using digital mind mapping on cognitive achievement and performance level of some basic skills in handball

    Directory of Open Access Journals (Sweden)

    Khaled Thabet Awad

    2016-07-01

    Full Text Available This study aims to identify the effect of using digital mind maps to on the cognitive achievement and the performance level of some basic skills in handball. Research population includes the first-year students at the Faculty of Physical Education in Port Said consisting of 200 students. Research Sample both researchers randomly selected the sample of first year students. The total sample size reaches 180 students with a 90.00%, after excluding failed students, re-registered students, the students of other levels of curriculum, practitioners to previous experiences and irregular students. The total number was 20 students with a percentage of (10.00%. They were divided into: Basic Sample: includes 80 students with a 44.44%. They were divided into two equal groups of 40 students. First Exploratory Sample: includes 60 students from the same research population and from outside the basic sample in order to find Tests Validity of the tests with a 33.33%. Second Exploratory Sample: includes 40 students from the same research population and from outside the basic sample in order to find Tests Reliability of the tests and identify the extent of pilot program appropriateness for the sample under discussion with a 22.22%. The first-year students were selected, according to the study plan, which contains a handball curriculum for the students of this educational level. Statistical Treatments: Both researchers conducted data statistically processes, using a statistical package for Social Sciences, SPSS ver. 20.0, in order to identify: arithmetic mean, standard deviation, median, skewness coefficient, correlation coefficient, discriminant validity coefficient, "t" test per one group, "t" test per two groups. The use of mind maps has a positive effect better than (explanation and model method on the cognitive achievement and the performance level of some basic skills in handball. Active learning techniques, such as the method of digital mind maps in teaching

  9. Digital breast tomosynthesis versus mammography and breast ultrasound: a multireader performance study

    International Nuclear Information System (INIS)

    Thibault, Fabienne; Malhaire, Caroline; Tardivon, Anne; Dromain, Clarisse; Balleyguier, Corinne S.; Breucq, Catherine; Steyaert, Luc; Baldan, Enrica; Drevon, Harir

    2013-01-01

    To compare the diagnostic performance of single-view breast tomosynthesis (BT) with that of dual-view mammography (MX); to assess the benefit of adding the craniocaudal (CC) mammographic view to BT, and of adding BT to MX plus breast ultrasound, considered to be the reference work-up. One hundred and fifty-five consenting patients with unresolved mammographic and/or ultrasound findings or breast symptoms underwent conventional work-up plus mediolateral oblique-view BT of the affected breast. The final study set in 130 patients resulted in 55 malignant and 76 benign and normal cases. Seven breast radiologists rated the cases through five sequential techniques using a BIRADS-based scale: MX, MX + ultrasound, MX + ultrasound + BT, BT, BT + MX(CC). Multireader, multicase receiver operating characteristic (ROC) analysis was performed and performance of the techniques was assessed from the areas under ROC curves. The performance of BT and of BT + MX(CC) was tested versus MX; the performance of MX + ultrasound + BT tested versus MX + ultrasound. Tomosynthesis was found to be non-inferior to mammography. BT + MX(CC) did not appear to be superior to MX, and MX + ultrasound + BT not superior to MX + ultrasound. Overall, none of the five techniques tested outperformed the others. Further clinical studies are needed to clarify the role of BT as a substitute for traditional work-up in the diagnostic environment. (orig.)

  10. THE DIGITAL ARCHIVING SYSTEM WITH TWITTER FOR LOCAL TRADITIONAL PERFORMING ARTS BY CITIZEN PARTICIPATION

    Directory of Open Access Journals (Sweden)

    Chiho Yoshida

    2011-12-01

    Full Text Available Local communities in mountainous and coast villages in Japan are facing problems related to aging and depopulation that discourage efforts to keep the traditional performing arts in the local community. The purpose of this study is to design an ―Archive and Community‖ model that creates a relationship between local citizens and non-citizens to keep the traditional performing arts in the local community by combining the traditional archiving system with social media like Twitter. This paper describes the experimental data results and discussions using the ―Archive and Community System‖ prototype.

  11. 75 FR 3666 - Digital Performance Right in Sound Recordings and Ephemeral Recordings for a New Subscription...

    Science.gov (United States)

    2010-01-22

    ... additions to Sec. 383.3 read as follows: Sec. 383.3 Royalty fees for public performances of sound recordings.... 383.4 to read as follows: Sec. 383.4 Terms for making payment of royalty fees. (a) Terms in general... Collective, late fees, statements of account, audit and verification of royalty payments and distributions...

  12. 75 FR 14074 - Digital Performance Right in Sound Recordings and Ephemeral Recordings for a New Subscription...

    Science.gov (United States)

    2010-03-24

    ...). The additions to Sec. 383.3 read as follows: Sec. 383.3 Royalty fees for public performances of sound... Sec. 383.4 to read as follows: Sec. 383.4 Terms for making payment of royalty fees. (a) Terms in... payments to the Collective, late fees, statements of account, audit and verification of royalty payments...

  13. 75 FR 6097 - Digital Performance Right in Sound Recordings and Ephemeral Recordings

    Science.gov (United States)

    2010-02-08

    ... amended by revising paragraph (b) to read as follows: Sec. 380.3 Royalty fees for the public performance... receive a credit in the amount of the minimum fee against any royalty fees payable in the same calendar... against any additional royalty fees payable in the same calendar year. Dated: February 2, 2010. James...

  14. Comparison of scatter rejection and low-contrast performance of scan equalization digital radiography (SEDR), slot-scan digital radiography, and full-field digital radiography systems for chest phantom imaging

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xinming; Shaw, Chris C.; Lai, Chao-Jen; Wang Tianpeng [Department of Imaging Physics, Digital Imaging Research Laboratory, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States)

    2011-01-15

    Purpose: To investigate and compare the scatter rejection properties and low-contrast performance of the scan equalization digital radiography (SEDR) technique to the slot-scan and conventional full-field digital radiography techniques for chest imaging. Methods: A prototype SEDR system was designed and constructed with an a-Se flat-panel (FP) detector to improve image quality in heavily attenuating regions of an anthropomorphic chest phantom. Slot-scanning geometry was used to reject scattered radiation without attenuating primary x rays. The readout scheme of the FP was modified to erase accumulated scatter signals prior to image readout. A 24-segment beam width modulator was developed to regulate x-ray exposures regionally and compensate for the low x-ray flux in heavily attenuating regions. To measure the scatter-to-primary ratios (SPRs), a 2 mm thick lead plate with a 2-D array of aperture holes was used to measure the primary signals, which were then subtracted from those obtained without the lead plate to determine scatter components. A 2-D array of aluminum beads (3 mm in diameter) was used as the low-contrast objects to measure the contrast ratios (CRs) and contrast-to-noise ratios (CNRs) for evaluating the low-contrast performance in chest phantom images. A set of two images acquired with the same techniques were subtracted from each other to measure the noise levels. SPRs, CRs, and CNRs of the SEDR images were measured in four anatomical regions of chest phantom images and compared to those of slot-scan images and full-field images acquired with and without antiscatter grid. Results: The percentage reduction of SPR (percentage of SPRs reduced with scatter removal/rejection methods relative to that for nongrid full-field imaging) averaged over four anatomical regions was measured to be 80%, 83%, and 71% for SEDR, slot-scan, and full-field with grid, respectively. The average CR over four regions was found to improve over that for nongrid full

  15. Comparison of scatter rejection and low-contrast performance of scan equalization digital radiography (SEDR), slot-scan digital radiography, and full-field digital radiography systems for chest phantom imaging

    International Nuclear Information System (INIS)

    Liu Xinming; Shaw, Chris C.; Lai, Chao-Jen; Wang Tianpeng

    2011-01-01

    Purpose: To investigate and compare the scatter rejection properties and low-contrast performance of the scan equalization digital radiography (SEDR) technique to the slot-scan and conventional full-field digital radiography techniques for chest imaging. Methods: A prototype SEDR system was designed and constructed with an a-Se flat-panel (FP) detector to improve image quality in heavily attenuating regions of an anthropomorphic chest phantom. Slot-scanning geometry was used to reject scattered radiation without attenuating primary x rays. The readout scheme of the FP was modified to erase accumulated scatter signals prior to image readout. A 24-segment beam width modulator was developed to regulate x-ray exposures regionally and compensate for the low x-ray flux in heavily attenuating regions. To measure the scatter-to-primary ratios (SPRs), a 2 mm thick lead plate with a 2-D array of aperture holes was used to measure the primary signals, which were then subtracted from those obtained without the lead plate to determine scatter components. A 2-D array of aluminum beads (3 mm in diameter) was used as the low-contrast objects to measure the contrast ratios (CRs) and contrast-to-noise ratios (CNRs) for evaluating the low-contrast performance in chest phantom images. A set of two images acquired with the same techniques were subtracted from each other to measure the noise levels. SPRs, CRs, and CNRs of the SEDR images were measured in four anatomical regions of chest phantom images and compared to those of slot-scan images and full-field images acquired with and without antiscatter grid. Results: The percentage reduction of SPR (percentage of SPRs reduced with scatter removal/rejection methods relative to that for nongrid full-field imaging) averaged over four anatomical regions was measured to be 80%, 83%, and 71% for SEDR, slot-scan, and full-field with grid, respectively. The average CR over four regions was found to improve over that for nongrid full

  16. SU-F-I-55: Performance Evaluation of Digital PET/CT: Medical Physics Basis for the Clinical Applications

    International Nuclear Information System (INIS)

    Zhang, J; Knopp, MV; Miller, M

    2016-01-01

    Purpose: Replacement of conventional PMT-based detector with next generation digital photon counting (DPC) detector is a technology leap for PET imaging. This study evaluated the performance and characteristics of the DPC system and its stability within a 1 year time window following its installation focusing on the medical physics basis for clinical applications. Methods: A digital PET/CT scanner using 1:1 coupling of 23,040 crystal: detector elements was introduced and became operational at OSU. We tested and evaluated system performance and characteristics using NEMA NU2-2012. System stabilities in timing resolution, energy resolution, detector temperature and humidity (T&H) were monitored over 1-yr. Timing, energy and spatial resolution were characterized across clinically relevant count rate range. CQIE uniformity PET and NEMA IEC-Body PET with hot spheres varying with sizes and contrasts were performed. PET reconstructed in standard(4mm), High(2mm) and Ultra-High(1mm) definitions were evaluated. Results: NEMA results showed PET spatial resolution (mm-FWHM) from 4.01&4.14 at 1cm to 5.82&6.17 at 20cm in transverse & axial. 322±3ps timing and 11.0% energy resolution were measured. 5.7kcps/MBq system sensitivity with 24kcps/MBq effective sensitivity was obtained. The peak-NECR was ∼171kcps with the effective peak-NECR >650kcps@50kBq/mL. Scatter fraction was ∼30%, and the maximum trues was >900kcps. NEMA IQ demonstrated hot sphere contrast ranging from ∼62%±2%(10mm) to ∼88%±2%(22mm), cold sphere contrast of ∼86%±2%(28mm) and ∼89%±3%(37mm) and excellent uniformity. Monitoring 1-yr stability, it revealed ∼1% change in timing, ±0.4% change in energy resolution, and <10% variations in T&H. CQIE PET gave <3% SUV variances in axial. 60%–100% recovery coefficients across sphere sizes and contrast levels were achieved. Conclusion: Characteristics and stability of the next generation DPC PET detector system over an 1-yr time window was excellent and

  17. SU-F-I-55: Performance Evaluation of Digital PET/CT: Medical Physics Basis for the Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J; Knopp, MV [The Ohio State University, Columbus, OH (United States); Miller, M [Philips Healthcare, Highland Heights, OH (United States)

    2016-06-15

    Purpose: Replacement of conventional PMT-based detector with next generation digital photon counting (DPC) detector is a technology leap for PET imaging. This study evaluated the performance and characteristics of the DPC system and its stability within a 1 year time window following its installation focusing on the medical physics basis for clinical applications. Methods: A digital PET/CT scanner using 1:1 coupling of 23,040 crystal: detector elements was introduced and became operational at OSU. We tested and evaluated system performance and characteristics using NEMA NU2-2012. System stabilities in timing resolution, energy resolution, detector temperature and humidity (T&H) were monitored over 1-yr. Timing, energy and spatial resolution were characterized across clinically relevant count rate range. CQIE uniformity PET and NEMA IEC-Body PET with hot spheres varying with sizes and contrasts were performed. PET reconstructed in standard(4mm), High(2mm) and Ultra-High(1mm) definitions were evaluated. Results: NEMA results showed PET spatial resolution (mm-FWHM) from 4.01&4.14 at 1cm to 5.82&6.17 at 20cm in transverse & axial. 322±3ps timing and 11.0% energy resolution were measured. 5.7kcps/MBq system sensitivity with 24kcps/MBq effective sensitivity was obtained. The peak-NECR was ∼171kcps with the effective peak-NECR >650kcps@50kBq/mL. Scatter fraction was ∼30%, and the maximum trues was >900kcps. NEMA IQ demonstrated hot sphere contrast ranging from ∼62%±2%(10mm) to ∼88%±2%(22mm), cold sphere contrast of ∼86%±2%(28mm) and ∼89%±3%(37mm) and excellent uniformity. Monitoring 1-yr stability, it revealed ∼1% change in timing, ±0.4% change in energy resolution, and <10% variations in T&H. CQIE PET gave <3% SUV variances in axial. 60%–100% recovery coefficients across sphere sizes and contrast levels were achieved. Conclusion: Characteristics and stability of the next generation DPC PET detector system over an 1-yr time window was excellent and

  18. L-Band Digital Aeronautical Communications System Engineering - Concepts of Use, Systems Performance, Requirements, and Architectures

    Science.gov (United States)

    Zelkin, Natalie; Henriksen, Stephen

    2010-01-01

    This NASA Contractor Report summarizes and documents the work performed to develop concepts of use (ConUse) and high-level system requirements and architecture for the proposed L-band (960 to 1164 MHz) terrestrial en route communications system. This work was completed as a follow-on to the technology assessment conducted by NASA Glenn Research Center and ITT for the Future Communications Study (FCS). ITT assessed air-to-ground (A/G) communications concepts of use and operations presented in relevant NAS-level, international, and NAS-system-level documents to derive the appropriate ConUse relevant to potential A/G communications applications and services for domestic continental airspace. ITT also leveraged prior concepts of use developed during the earlier phases of the FCS. A middle-out functional architecture was adopted by merging the functional system requirements identified in the bottom-up assessment of existing requirements with those derived as a result of the top-down analysis of ConUse and higher level functional requirements. Initial end-to-end system performance requirements were derived to define system capabilities based on the functional requirements and on NAS-SR-1000 and the Operational Performance Assessment conducted as part of the COCR. A high-level notional architecture of the L-DACS supporting A/G communication was derived from the functional architecture and requirements.

  19. Evaluation of entrance skin air kerma in digital and conventional pediatric chest examinations performed in Parana-Brazil

    International Nuclear Information System (INIS)

    Oliveira, Ana L.R.; Schelin, Hugo R.; Lunelli, Neuri; Paschuk, Sergei; Tilly Jr, Joao G.; Rogacheski, Enio; Khoury, Helen J.; Ferreira, Jose R.L.

    2008-01-01

    Full text: In pediatric radiology it is important to evaluate patient exposure due to the high sensitivity of his/her tissue and his/her relatively longer life expectancy, which may increase the chance of radiogenic cancer development. Special attention is necessary when digital systems are used since a high dosage level for the patient may go unnoticed because the resulting image is not overexposed. The purpose of this work is to evaluate the Entrance Skin Air Kerma (ESAK) in pediatric patients submitted to digital and conventional chest examinations performed in the State of Parana, located in the Southern region of Brazil. The survey was performed in two hospitals, one located in Curitiba, the Capital of the State (A) and the other in the city of Cascavel (B). Hospital A uses a conventional image system and Hospital B uses a CR digital system. The study group consisted of 50 patients (from 2 days to six years of age) undergoing chest PA/AP examinations. At the time of the examination, the exposure parameters (kV, mAs, focal-film distance, etc) and the gender, height, weight and age of the patient were recorded. To evaluate the Entrance Skin Air Kerma (ESAK), two TLD-100 dosimeters were packaged in a polyethylene case, heat sealed and placed on the surface of each patient. The TLDs were calibrated the Metrology Laboratory of Ionizing Radiation of the Federal University of Pernambuco. The TLDs were processed on a Victoreen readout system model 2800M. The results showed that the kilovoltage values used in Hospital A are in the range of 46 to 65 kV with the average value of 51,7 kV, while the ones in Hospital B are in the range of 65 to 80 kV. On the other hand, even though hospital B uses the CR system, the mAs used for the chest exams are 4 times higher than the ones used in Hospital A. For Hospital A, the mean ESAK value was 0.044 mGy (min: 0.08 and max 0.146 mGy), and for Hospital B the mean ESAK value was 0.368 mGy (min: 0.021 and max 1.21mGy). The results made

  20. MONITORIZATION OF THERAPEUTICAL ACT PERFORMANCE IN THE DIGITALIZED ERA - DETERMINATION OF PATIENT’S SATISFACTION -

    Directory of Open Access Journals (Sweden)

    Mihai LUCHIAN

    2017-06-01

    Full Text Available Improvement of a patient’s health condition assumes the application, in the most convenient moment of time, of complete therapeutical actions based on a doubtless diagnosis. Such services are appreciated by the patient in most varied ways, and compared with the health services administered or provided by similar medical structures. Any manifested discontent may have immediate or latent repecussions upon the dignity, professional image and, equally, upon the economic efficiency of the medical structure involved. The system of performance indices refers directly and pragmatically to a quasi-objective quantification of the quality of the therapeutical acts administered, within some time interval, by the medical structure in charge with this. Analysis of qualiy criteria attainment involves a relatively complex graph of activities, among which mandatory are: identification and elimination of the causes of insatisfaction, establishment of corrective measures and directions when problems do appear, interrogation of patients as to their expressed discontents (as well as comparatively with their expectations, total involvement of all members of the medical team in solving patients’ needs. Critical analysis and periodical elaboration of new performance standards capable of assuring a high level of health services’ quality and, implicitly, of the satisfaction level expected by patients.

  1. Performance evaluation of a retrofit digital detector-based mammography system.

    Science.gov (United States)

    Marshall, Nicholas W; van Ongeval, Chantal; Bosmans, Hilde

    2016-02-01

    A retrofit flat panel detector was integrated with a GE DMR+ analog mammography system and characterized using detective quantum efficiency (DQE). Technical system performance was evaluated using the European Guidelines protocol, followed by a limited evaluation of clinical image quality for 20 cases using image quality criteria in the European Guidelines. Optimal anode/filter selections were established using signal difference-to-noise ratio measurements. Only small differences in peak DQE were seen between the three anode/filter settings, with an average value of 0.53. For poly(methyl methacrylate) (PMMA) thicknesses above 60 mm, the Rh/Rh setting was the optimal anode/filter setting. The system required a mean glandular dose of 0.54 mGy at 30 kV Rh/Rh to reach the Acceptable gold thickness limit for 0.1 mm details. Imaging performance of the retrofit unit with the GE DMR+ is notably better than of powder based computed radiography systems and is comparable to current flat panel FFDM systems. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  2. DQE of wireless digital detectors: Comparative performance with differing filtration schemes

    International Nuclear Information System (INIS)

    Samei, Ehsan; Murphy, Simon; Christianson, Olav

    2013-01-01

    Purpose: Wireless flat panel detectors are gaining increased usage in portable medical imaging. Two such detectors were evaluated and compared with a conventional flat-panel detector using the formalism of the International Electrotechnical Commission (IEC 62220-1) for measuring modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) using two different filtration schemes.Methods: Raw images were acquired for three image receptors (DRX-1C and DRX-1, Carestream Health; Inc., Pixium 4600, Trixell) using a radiographic system with a well-characterized output (Philips Super80 CP, Philips Healthcare). Free in-air exposures were measured using a calibrated radiation meter (Unfors Mult-O-Meter Type 407, Unfors Instruments AB). Additional aluminum filtration and a new alternative combined copper-aluminum filtration were used to conform the x ray output to IEC-specified beam quality definitions RQA5 and RQA9. Using the IEC 62220-1 formalism, each detector was evaluated at X N /2, X N , and 2X N , where the normal exposure level to the detector surface (X N ) was set to 8.73 μGy (1.0 mR). The prescribed edge test device was used to evaluate the MTF, while the NNPS was measured using uniform images. The DQE was then calculated from the MTF and NNPS and compared across detectors, exposures, and filtration schemes.Results: The three DR systems had largely comparable MTFs with DRX-1 demonstrating lower values above 1.0 cycles/mm. At each exposure, DRX-1C and Pixium detectors demonstrated better noise performance than that of DRX-1. Zero-frequency DQEs for DRX-1C, Pixium, and DRX-1 detectors were approximately 74%, 63%, and 38% for RQA5 and 50%, 42%, and 28% for RQA9, respectively.Conclusions: DRX-1C detector exhibited superior DQE performance compared to Pixium and DRX-1. In terms of filtration, the alternative filtration was found to provide comparable performance in terms of rank ordering of different detectors with

  3. DQE of wireless digital detectors: Comparative performance with differing filtration schemes

    Energy Technology Data Exchange (ETDEWEB)

    Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Departments of Radiology, Biomedical Engineering, Physics, and Electrical and Computer Engineering, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Murphy, Simon; Christianson, Olav [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States)

    2013-08-15

    Purpose: Wireless flat panel detectors are gaining increased usage in portable medical imaging. Two such detectors were evaluated and compared with a conventional flat-panel detector using the formalism of the International Electrotechnical Commission (IEC 62220-1) for measuring modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) using two different filtration schemes.Methods: Raw images were acquired for three image receptors (DRX-1C and DRX-1, Carestream Health; Inc., Pixium 4600, Trixell) using a radiographic system with a well-characterized output (Philips Super80 CP, Philips Healthcare). Free in-air exposures were measured using a calibrated radiation meter (Unfors Mult-O-Meter Type 407, Unfors Instruments AB). Additional aluminum filtration and a new alternative combined copper-aluminum filtration were used to conform the x ray output to IEC-specified beam quality definitions RQA5 and RQA9. Using the IEC 62220-1 formalism, each detector was evaluated at X{sub N}/2, X{sub N}, and 2X{sub N}, where the normal exposure level to the detector surface (X{sub N}) was set to 8.73 μGy (1.0 mR). The prescribed edge test device was used to evaluate the MTF, while the NNPS was measured using uniform images. The DQE was then calculated from the MTF and NNPS and compared across detectors, exposures, and filtration schemes.Results: The three DR systems had largely comparable MTFs with DRX-1 demonstrating lower values above 1.0 cycles/mm. At each exposure, DRX-1C and Pixium detectors demonstrated better noise performance than that of DRX-1. Zero-frequency DQEs for DRX-1C, Pixium, and DRX-1 detectors were approximately 74%, 63%, and 38% for RQA5 and 50%, 42%, and 28% for RQA9, respectively.Conclusions: DRX-1C detector exhibited superior DQE performance compared to Pixium and DRX-1. In terms of filtration, the alternative filtration was found to provide comparable performance in terms of rank ordering of different

  4. On the Performance Analysis of Digital Communication Systems Perturbed by Non-Gaussian Noise and Interference

    KAUST Repository

    Soury, Hamza

    2016-06-29

    The Gaussian distribution is typically used to model the additive noise affecting communication systems. However, in many cases the noise cannot be modeled by a Gaussian distribution. In this thesis, we investigate the performance of different communication systems perturbed by non-Gaussian noise. Three families of noise are considered in this work, namely the generalized Gaussian noise, the Laplace noise/interference, and the impulsive noise that is modeled by an α-stable distribution. More specifically, in the first part of this thesis, the impact of an additive generalized Gaussian noise is studied by computing the average symbol error rate (SER) of one dimensional and two dimensional constellations in fading environment. We begin by the simple case of two symbols, i.e. binary phase shift keying (BPSK) constellation. From the results of this constellation, we extended the work to the average SER of an M pulse amplitude modulation (PAM). The first 2 − D constellation is the M quadrature amplitude modulation (QAM) (studied for two geometric shapes, namely square and rectangular), which is the combination of two orthogonal PAM signals (in-phase and quadrature phase PAM). In the second part, the system performance of a circular constellation, namely M phase shift keying (MPSK) is studied in conjunction with a Laplace noise with independent noise components. A closed form and an asymptotic expansion of the SER are derived for two detectors, maximum likelihood and minimum distance detectors. Next, we look at the intra cell interference of a full duplex cellular network which is shown to follow a Laplacian distribution with dependent, but uncorrelated, complex components. The densities of that interference are expressed in a closed form in order to obtain the SER of several communication systems (BPSK, PAM, QAM, and MPSK). Finally, we study the statistics of the α-stable distribution. Those statistics are expressed in closed form in terms of the Fox H function and

  5. Performance evaluation of a digital mammography unit using a contrast-detail phantom

    Science.gov (United States)

    Elizalde-Cabrera, J.; Brandan, M.-E.

    2015-01-01

    The relation between image quality and mean glandular dose (MGD) has been studied for a Senographe 2000D mammographic unit used for research in our laboratory. The magnitudes were evaluated for a clinically relevant range of acrylic thicknesses and radiological techniques. The CDMAM phantom was used to determine the contrast-detail curve. Also, an alternative method based on the analysis of signal-to-noise (SNR) and contrast-to-noise (CNR) ratios from the CDMAM image was proposed and applied. A simple numerical model was utilized to successfully interpret the results. Optimum radiological techniques were determined using the figures-of-merit FOMSNR=SNR2/MGD and FOMCNR=CNR2/MGD. Main results were: the evaluation of the detector response flattening process (it reduces by about one half the spatial non-homogeneities due to the X- ray field), MGD measurements (the values comply with standards), and verification of the automatic exposure control performance (it is sensitive to fluence attenuation, not to contrast). For 4-5 cm phantom thicknesses, the optimum radiological techniques were Rh/Rh 34 kV to optimize SNR, and Rh/Rh 28 kV to optimize CNR.

  6. Performance analysis of general purpose and digital signal processor kernels for heterogeneous systems-on-chip

    Directory of Open Access Journals (Sweden)

    T. von Sydow

    2003-01-01

    Full Text Available Various reasons like technology progress, flexibility demands, shortened product cycle time and shortened time to market have brought up the possibility and necessity to integrate different architecture blocks on one heterogeneous System-on-Chip (SoC. Architecture blocks like programmable processor cores (DSP- and GPP-kernels, embedded FPGAs as well as dedicated macros will be integral parts of such a SoC. Especially programmable architecture blocks and associated optimization techniques are discussed in this contribution. Design space exploration and thus the choice which architecture blocks should be integrated in a SoC is a challenging task. Crucial to this exploration is the evaluation of the application domain characteristics and the costs caused by individual architecture blocks integrated on a SoC. An ATE-cost function has been applied to examine the performance of the aforementioned programmable architecture blocks. Therefore, representative discrete devices have been analyzed. Furthermore, several architecture dependent optimization steps and their effects on the cost ratios are presented.

  7. Digital Tools and Challenges to Institutional Traditions of Learning: Technologies, Social Memory and the Performative Nature of Learning

    Science.gov (United States)

    Saljo, R.

    2010-01-01

    The purpose of this article is to offer some reflections on the relationships between digital technologies and learning. It is argued that activities of learning, as they have been practised within institutionalized schooling, are coming under increasing pressure from the developments of digital technologies and the capacities to store, access and…

  8. Comparison of performance of analog-to-digital converters (ADC) for pulse height analyzers

    International Nuclear Information System (INIS)

    Suzuki, Shogo; Hirai, Shoji

    1981-01-01

    In the recent ADCs for pulse height analyzers (PHA), Wilkinson type is a leading one, and those with 50 to 200 MHz clock frequency and 8K channel are mostly on the market. The comparison of the performance of ADCs was conducted under the condition of using these multi-channel PHAs as γ-ray spectrometers. The following three ADCs were compared: ADC incorporated in CANBERRA 8100 MCA, and CANBERRA 8060 ADCs used as the ADCs for 1st and 2nd GAMA systems. In this case, the conversion gains of these ADCs were set at 4K because the memory of 8100 MCA was 4K, and the GAMA systems were also mostly operated at 4K. In this paper, report is made on the measurements of dead time, the change of γ peaks immediately after the power was turned on, the temperature dependence of ADCs the long term stability of ADCs, derivative non-linearity, and integration non-linearity. The dead time of the ADC of 8100 CMA was shorter in the range up to 1000 channels. The temperature dependence was -0.017%/deg C in 8100 MCA, and -0.061 and -0.072%/deg C in GAMA. The long term stability was -0.02%/14 hr in 8100 MCA, and -0.027%/14 hr in 8060 of 1st GAMA. The derivative non-linearity was 0.45% in 8100 MCA, 0.67% in 8060 of 1st GAMA, and the integration non-linearity was 0.075% for 8100 MCA, and 0.085 - 0.1% in 8060 ADCs. Also, the change of γ peaks immediately after the power was turned on for 8100 ADC was better than that of 8060 ADC. (Wakatsuki, Y.)

  9. Short-term memory digit-span performance under auditory and visual contexts as a function of rate of digit presentation.

    Science.gov (United States)

    Vitulli, W F; McNeil, M J

    1990-12-01

    This exploratory investigation concerned the effects of both auditory and visual context variations on the immediate recall of a series of digits presented on a computer screen (CRT). 5 intensities of background noise and 5 background hues were presented randomly to 110 undergraduate volunteers as they studied 25 numerals ranging from 1 to 5 at rates of change of either 1 or 3 sec. per numeral timed from the onset of the previous numeral. A 2 x 2 x 5 mixed split-plot factorial analysis of variance gave a significant difference in mean immediate-recall scores between rates of digit presentation with better recall associated with the 3-sec. rate. There was no significant main effect in recall scores for auditory vs color contexts, yet a post hoc analysis of variance for successive stages followed by Scheffé comparisons showed that across auditory intensities, Stages 3 and 4 and 5 (combined) had significantly higher immediate recall scores than Stages 1 and 2 (combined). This improvement across stages was not found under the visual (color) series. There was a three-way interaction for modality-contexts x rates x levels explained by the partitioning of stages which differed for auditory and for visual contexts. Results are discussed in terms of effects of modality.

  10. Analysis of the imaging performance in indirect digital mammography detectors by linear systems and signal detection models

    International Nuclear Information System (INIS)

    Liaparinos, P.; Kalyvas, N.; Kandarakis, I.; Cavouras, D.

    2013-01-01

    Purpose: The purpose of this study was to provide an analysis of imaging performance in digital mammography, using indirect detector instrumentation, by combining the Linear Cascaded Systems (LCS) theory and the Signal Detection Theory (SDT). Observer performance was assessed, by examining frequently employed detectors, consisting of phosphor-based X-ray converters (granular Gd 2 O 2 S:Tb and structural CsI:Tl), coupled with the recently introduced complementary metal-oxide-semiconductor (CMOS) sensor. By applying combinations of various irradiation conditions (filter-target and exposure levels at 28 kV) on imaging detectors, our study aimed to find the optimum system set-up for digital mammography. For this purpose, the signal to noise transfer properties of the medical imaging detectors were examined for breast carcinoma detectability. Methods: An analytical model was applied to calculate X-ray interactions within software breast phantoms and detective media. Modeling involved: (a) three X-ray spectra used in digital mammography: 28 kV Mo/Mo (Mo: 0.030 mm), 28 kV Rh/Rh (Rh: 0.025 mm) and 28 kV W/Rh (Rh: 0.060 mm) at different entrance surface air kerma (ESAK) of 3 mGy and 5 mGy, (b) a 5 cm thick Perspex software phantom incorporating a small Ca lesion of varying size (0.1–1 cm), and (c) two 200 μm thick phosphor-based X-ray converters (Gd2O2S:Tb, CsI:Tl), coupled to a CMOS based detector of 22.5 μm pixel size. Results: Best (lowest) contrast threshold (CT) values were obtained with the combination: (i) W/Rh target-filter, (ii) 5 mGy (ESAK), and (iii) CsI:Tl-CMOS detector. For lesion diameter 0.5 cm the CT was found improved, in comparison to other anode/filter combinations, approximately 42% than Rh/Rh and 55% than Mo/Mo, for small sized carcinoma (0.1 cm) and approximately 50% than Rh/Rh and 125% than Mo/Mo, for big sized carcinoma (1 cm), considering 5 mGy X-ray beam. By decreasing lesion diameter and thickness, a limiting CT (100%) was occurred for size

  11. Evaluation of PET performance and MR compatibility of a preclinical PET/MR insert with digital silicon photomultiplier technology

    Energy Technology Data Exchange (ETDEWEB)

    Hallen, Patrick; Schug, David; Wehner, Jakob [Department of Physics of Molecular Imaging Systems, RWTH Aachen University (Germany); Weissler, Bjorn [Department of Chemical Application Research, Philips Research (Germany); Gebhardt, Pierre [Division of Imaging Sciences and Biomedical Engineering, King’s College London (United Kingdom); Goldschmidt, Benjamin [Department of Physics of Molecular Imaging Systems, RWTH Aachen University (Germany); Salomon, Andre [Department of Oncology Solutions, Philips Research (Germany); Duppenbecker, Peter [Department of Physics of Molecular Imaging Systems, RWTH Aachen University (Germany); Kiessling, Fabian [Institute for Experimental Molecular Imaging, RWTH Aachen University (Germany); Schultz, Volkmar [Department of Physics of Molecular Imaging Systems, RWTH Aachen University (Germany)

    2015-05-18

    In this work we present detailed characterizations of our preclinical high resolution PET/MR insert based on the Hyperion-IID platform. The PET/MR insert consists of a ring of 10 singles detection modules, each comprising 2x3 scintillation detector stacks. Each detector stack features a 30x30 pixelated LYSO crystal array with a height of 12 mm and a pitch of 1 mm, coupled via a slit 2 mm light guide to a digital SiPM tile. The PET performance is stable under a wide range of operating points. The spatial resolution is below 1Ä,mm and the CRT reaches 260 or 450 ps depending on trigger settings. The energy resolution is 12.6% FWHM. The characterization of the MR compatibility showed no relevant degradation in PET performance during MRI operation. On the MRI side, we observe a degradation in B0 homogeneity from a VRMS of 0.03 ppm to 0.08 ppm with active shimming, while observing only minor degradations in the B0 field. The noise floor is slightly increased by 2-15% without any observable dependence on the activity. The Z gradients induces an observable eddy current inside the PET inserts which can lead to ghosting artifacts for EPI sequences. However, we don't observe any visible image degradation for widely used anatomical imaging sequences such as gradient echo and turbo spin echo sequences. To prove the viability of our PET/MR insert for in vivo small animal studies, we successfully performed a longitudinal mouse study with subcutaneously injected tumor model cells. The simultaneously acquired PET/MR images provide a high level of anatomical information and soft tissue contrast in the MR layer together with a high resolution image of the FDG tracer distribution in the PET layer.

  12. Benchmarking the performance of fixed-image receptor digital radiographic systems part 1: a novel method for image quality analysis.

    Science.gov (United States)

    Lee, Kam L; Ireland, Timothy A; Bernardo, Michael

    2016-06-01

    This is the first part of a two-part study in benchmarking the performance of fixed digital radiographic general X-ray systems. This paper concentrates on reporting findings related to quantitative analysis techniques used to establish comparative image quality metrics. A systematic technical comparison of the evaluated systems is presented in part two of this study. A novel quantitative image quality analysis method is presented with technical considerations addressed for peer review. The novel method was applied to seven general radiographic systems with four different makes of radiographic image receptor (12 image receptors in total). For the System Modulation Transfer Function (sMTF), the use of grid was found to reduce veiling glare and decrease roll-off. The major contributor in sMTF degradation was found to be focal spot blurring. For the System Normalised Noise Power Spectrum (sNNPS), it was found that all systems examined had similar sNNPS responses. A mathematical model is presented to explain how the use of stationary grid may cause a difference between horizontal and vertical sNNPS responses.

  13. Durability Analysis and Experimental Validation of Environmental Barrier Coating (EBC Performance Using Combined Digital Image Correlation and NDE

    Directory of Open Access Journals (Sweden)

    Ali Abdul-Aziz

    2016-12-01

    Full Text Available To understand the failure mechanism or to predict the spallation life of environmental barrier coatings (EBC on fiber reinforced ceramic matrix composites, the fracture strength of EBC and the process of the crack growth in EBC layers need to be experimentally determined under standard or simulated engine operating conditions. The current work considers a multi layered barium strontium aluminum silicate (BSAS-based EBC-coated, melt infiltrated silicon carbide fiber reinforced silicon carbide matrix composite (MI SiC/SiC specimen that was tensile tested at room temperature. Numerous tests were performed under tensile loading conditions, and the specimen was loaded until failure under pre-determined stress levels. The specimen was examined with optical microscopy, scanning electron microscopy (SEM, computed tomography (CT scan, and digital image correlation (DIC camera. Observation from the computed tomography scanning, the SEM, and the optical microscopy did not offer conclusive information concerning the cracks that spawned during the tests. However, inspection with the DIC camera offered some indication that cracks had developed and allowed their detection and the location of their initiation site. Thus, this study provides detailed discussion of the results obtained from the experimental investigation and the nondestructive evaluation (NDE, and it also includes assessment of the stress response predicted by analytical modeling and their impact on EBC durability and crack growth formation under complex loading settings.

  14. Performance of computer-aided detection applied to full-field digital mammography in detection of breast cancers

    International Nuclear Information System (INIS)

    Sadaf, Arifa; Crystal, Pavel; Scaranelo, Anabel; Helbich, Thomas

    2011-01-01

    Objective: The aim of this retrospective study was to evaluate performance of computer-aided detection (CAD) with full-field digital mammography (FFDM) in detection of breast cancers. Materials and Methods: CAD was retrospectively applied to standard mammographic views of 127 cases with biopsy proven breast cancers detected with FFDM (Senographe 2000, GE Medical Systems). CAD sensitivity was assessed in total group of 127 cases and for subgroups based on breast density, mammographic lesion type, mammographic lesion size, histopathology and mode of presentation. Results: Overall CAD sensitivity was 91% (115 of 127 cases). There were no statistical differences (p > 0.1) in CAD detection of cancers in dense breasts 90% (53/59) versus non-dense breasts 91% (62/68). There was statistical difference (p 20 mm 97% (22/23). Conclusion: CAD applied to FFDM showed 100% sensitivity in identifying cancers manifesting as microcalcifications only and high sensitivity 86% (71/83) for other mammographic appearances of cancer. Sensitivity is influenced by lesion size. CAD in FFDM is an adjunct helping radiologist in early detection of breast cancers.

  15. Design and application of a structured phantom for detection performance comparison between breast tomosynthesis and digital mammography

    Science.gov (United States)

    Cockmartin, L.; Marshall, N. W.; Zhang, G.; Lemmens, K.; Shaheen, E.; Van Ongeval, C.; Fredenberg, E.; Dance, D. R.; Salvagnini, E.; Michielsen, K.; Bosmans, H.

    2017-02-01

    This paper introduces and applies a structured phantom with inserted target objects for the comparison of detection performance of digital breast tomosynthesis (DBT) against 2D full field digital mammography (FFDM). The phantom consists of a 48 mm thick breast-shaped polymethyl methacrylate (PMMA) container filled with water and PMMA spheres of different diameters. Three-dimensionally (3D) printed spiculated masses (diameter range: 3.8-9.7 mm) and non-spiculated masses (1.6-6.2 mm) along with microcalcifications (90-250 µm) were inserted as targets. Reproducibility of the phantom application was studied on a single system using 30 acquisitions. Next, the phantom was evaluated on five different combined FFDM & DBT systems and target detection was compared for FFDM and DBT modes. Ten phantom images in both FFDM and DBT modes were acquired on these 5 systems using automatic exposure control. Five readers evaluated target detectability. Images were read with the four-alternative forced-choice (4-AFC) paradigm, with always one segment including a target and 3 normal background segments. The percentage of correct responses (PC) was assessed based on 10 trials of each reader for each object type, size and imaging modality. Additionally, detection threshold diameters at 62.5 PC were assessed via non-linear regression fitting of the psychometric curve. The reproducibility study showed no significant differences in PC values. Evaluation of target detection in FFDM showed that microcalcification detection thresholds ranged between 110 and 118 µm and were similar compared to the detection in DBT (range of 106-158 µm). In DBT, detection of both mass types increased significantly (p  =  0.0001 and p  =  0.0002 for non-spiculated and spiculated masses respectively) compared to FFDM, achieving almost 100% detection for all spiculated mass diameters. In conclusion, a structured phantom with inserted targets was able to show evidence for detectability

  16. Performance of breast cancer screening using digital breast tomosynthesis: results from the prospective population-based Oslo Tomosynthesis Screening Trial.

    Science.gov (United States)

    Skaane, Per; Sebuødegård, Sofie; Bandos, Andriy I; Gur, David; Østerås, Bjørn Helge; Gullien, Randi; Hofvind, Solveig

    2018-02-10

    Digital breast tomosynthesis (DBT) has the potential to overcome limitations of conventional mammography. This study investigated the effects of addition of DBT on interval and detected cancers in population-based screening. Oslo Tomosynthesis Screening Trial (OTST) was a prospective, independent double-reading trial inviting women 50-69 years biennially, comparing full-field digital mammography (FFDM) plus DBT with FFDM alone. Performance indicators and characteristics of screen-detected and interval cancers were compared with two previous FFDM rounds. 24,301 consenting women underwent FFDM + DBT screening over a 2-year period. Results were compared with 59,877 FFDM examinations during prior rounds. Addition of DBT resulted in a non-significant increase in sensitivity (76.2%, 378/496, vs. 80.8%, 227/281, p = 0.151) and a significant increase in specificity (96.4%, 57229/59381 vs. 97.5%, 23427/24020, p < .001). Number of recalls per screen-detected cancer decreased from 6.7 (2530/378) to 3.6 (820/227) with DBT (p < .001). Cancer detection per 1000 women screened increased (6.3, 378/59877, vs. 9.3, 227/24301, p < .001). Interval cancer rate per 1000 screens for FFDM + DBT remained similar to previous FFDM rounds (2.1, 51/24301 vs. 2.0, 118/59877, p = 0.734). Interval cancers post-DBT were comparable to prior rounds but significantly different in size, grade, and node status from cancers detected only using DBT. 39.6% (19/48) of interval cancers had positive nodes compared with only 3.9% (2/51) of additional DBT-only-detected cancers. DBT-supplemented screening resulted in significant increases in screen-detected cancers and specificity. However, no significant change was observed in the rate, size, node status, or grade of interval cancers. ClinicalTrials.gov: NCT01248546.

  17. Derivation and Cross-Validation of Cutoff Scores for Patients With Schizophrenia Spectrum Disorders on WAIS-IV Digit Span-Based Performance Validity Measures.

    Science.gov (United States)

    Glassmire, David M; Toofanian Ross, Parnian; Kinney, Dominique I; Nitch, Stephen R

    2016-06-01

    Two studies were conducted to identify and cross-validate cutoff scores on the Wechsler Adult Intelligence Scale-Fourth Edition Digit Span-based embedded performance validity (PV) measures for individuals with schizophrenia spectrum disorders. In Study 1, normative scores were identified on Digit Span-embedded PV measures among a sample of patients (n = 84) with schizophrenia spectrum diagnoses who had no known incentive to perform poorly and who put forth valid effort on external PV tests. Previously identified cutoff scores resulted in unacceptable false positive rates and lower cutoff scores were adopted to maintain specificity levels ≥90%. In Study 2, the revised cutoff scores were cross-validated within a sample of schizophrenia spectrum patients (n = 96) committed as incompetent to stand trial. Performance on Digit Span PV measures was significantly related to Full Scale IQ in both studies, indicating the need to consider the intellectual functioning of examinees with psychotic spectrum disorders when interpreting scores on Digit Span PV measures. © The Author(s) 2015.

  18. Performance evaluation of a sub-millimeter spatial resolution PET detector module using a digital silicon photomultiplier coupled LGSO array

    Energy Technology Data Exchange (ETDEWEB)

    Leem, Hyun Tae [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Choi, Yong, E-mail: ychoi@sogang.ac.kr [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Kim, Kyu Bom; Lee, Sangwon [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Yamamoto, Seiichi [Department of Medical Technology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Yeom, Jung-Yeol, E-mail: jungyeol@korea.ac.kr [School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of)

    2017-02-21

    In positron emission tomography (PET) for breast, brain and small animal imaging, the spatial resolution of a PET detector is crucial to obtain high quality PET images. In this study, a PET detector for sub-millimeter spatial resolution imaging purpose was assembled using 4×4 pixels of a digital silicon photomultiplier (dSiPM, DPC-3200-22-44, Philips) coupled with a 15×15 LGSO array with BaSO{sub 4} reflector, and a 1 mm thick acrylic light guide for light distribution between the dSiPM pixels. The active area of each dSiPM pixel was 3.2×3.9 mm{sup 2} and the size of each LGSO scintillator element was 0.7×0.7×6 mm{sup 3}. In this paper, we experimentally demonstrated the performance of the PET detector by measuring the energy resolution, 2D flood map, peak to valley (P/V) ratio, and coincidence resolving time (CRT). All measurements were performed at a temperature of 10±1 ℃. The average energy resolution was 15.6% (without correcting for saturation effects) at 511 keV and the best CRT was 242±5 ps. The 2D flood map obtained with an energy window of 400–600 keV demonstrated clear identification of all pixels, and the average P/V ratio of the X- and Y-directions were 7.31 and 7.81, respectively. This study demonstrated that the PET detector could be suitable for application in high resolution PET while achieving good timing resolution.

  19. Dose and diagnostic performance comparison between phase-contrast mammography with synchrotron radiation and digital mammography: a clinical study report.

    Science.gov (United States)

    Fedon, Christian; Rigon, Luigi; Arfelli, Fulvia; Dreossi, Diego; Quai, Elisa; Tonutti, Maura; Tromba, Giuliana; Cova, Maria Assunta; Longo, Renata

    2018-01-01

    Two dosimetric quantities [mean glandular dose (MGD) and entrance surface air kerma (ESAK)] and the diagnostic performance of phase-contrast mammography with synchrotron radiation (MSR) are compared to conventional digital mammography (DM). Seventy-one patients (age range, 41 to 82 years) underwent MSR after a DM examination if questionable or suspicious breast abnormalities were not clarified by ultrasonography. The MGD and the ESAK delivered in both examinations were evaluated and compared. Two on-site radiologists rated the images in consensus according to the Breast Imaging Reporting and Data System assessment categories, which were then correlated with the final diagnoses by means of statistical generalized linear models (GLMs). Receiver operating characteristic curves were also used to assess the diagnostic performance by comparing the area under the curve (AUC). An important MGD and ESAK reduction was observed in MSR due to the monoenergetic beam. In particular, an average 43% reduction was observed for the MGD and a reduction of more than 50% for the ESAK. GLM showed higher diagnostic accuracy, especially in terms of specificity, for MSR, confirmed by AUC analysis ([Formula: see text]). The study design implied that the population was characterized by a high prevalence of disease and that the radiologists, who read the DM images before referring the patient to MSR, could have been influenced in their assessments. Within these limitations, the use of synchrotron radiation with the phase-contrast technique applied to mammography showed an important dose reduction and a higher diagnostic accuracy compared with DM. These results could further encourage research on the translation of x-ray phase-contrast imaging into the clinics.

  20. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, W.; Martinez-Guridi, G.

    2010-01-01

    New and advanced reactors will use integrated digital instrumentation and control (I and C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I and C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I and C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I and C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I and C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I and C conditions as part of the design process and the HSI features and functions that support operators to monitor I and C performance and manage I and C degradations when they occur. In addition, we identified topics for future research.

  1. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J.M.; W. Gunther, G. Martinez-Guridi

    2010-02-26

    New and advanced reactors will use integrated digital instrumentation and control (I&C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I&C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I&C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I&C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I&C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I&C conditions as part of the design process and the HSI features and functions that support operators to monitor I&C performance and manage I&C degradations when they occur. In addition, we identified topics for future research.

  2. Digital Living at Home

    DEFF Research Database (Denmark)

    Andersen, Pernille Viktoria Kathja; Christiansen, Ellen Tove

    2013-01-01

    of these user voices has directed us towards a ‘home-keeping’ design discourse, which opens new horizons for design of digital home control systems by allowing users to perform as self-determined controllers and groomers of their habitat. The paper concludes by outlining the implications of a ‘home......Does living with digital technology inevitably lead to digital living? Users talking about a digital home control system, they have had in their homes for eight years, indicate that there is more to living with digital technology than a functional-operational grip on regulation. Our analysis......-keeping’ design discourse....

  3. Lessons learned from the licensing process and the operational performance of the important to safety digital application implemented at the Mexican nuclear facilities

    International Nuclear Information System (INIS)

    Ledesma-Carrion, R.

    1998-01-01

    This paper describes the main concerns detected during the licensing processes performed by the Mexican Nuclear Regulatory Commission (CNSNS) for the NUMAC-PRNM, the Integrated Computer Systems at the Laguna Verde Nuclear Power Station (LVNPS) and for the Digital Control Console of the Triga Mark III Research Reactor (TMRR). The review and approval process was performed following the guidelines of the US Nuclear Regulatory Commission (USNRC); the regulatory frame applied includes the Code of Federal Regulation (10CFR50), some Regulatory Guides, such as: RG 1.152, RG 1.153, some Industrial Standards, for example: IEEE-279, IEEE-603, IEEE-7.4.3-2. Also, based on the operational experience taken from the LVNPS License Event Report (LER) reported under the 10CFR50.72 and 10CFR50.73 USNRC rules, and from the Report of Events to be Analyzed (REA) issued for a CNSNS agreement with the utility stated by the necessity to determine failure rates of digital equipment, some case studies and a preliminary failure cause classification is shown. The Event Report evaluation covered topics related to the software, hardware and firmware issues. Finally, the lessons learned from the licensing assessments and from the operational experience of the digital applications implemented are presented. It will also give the regulatory activities related to an IAEA international cooperation project on I and C digital upgrade concerns. (author)

  4. Effects of voice timbre and accompaniment on working memory as measured by sequential monosyllabic digit recall performance.

    Science.gov (United States)

    Silverman, Michael J; Schwartzberg, Edward T

    2014-01-01

    Information is often paired with music in an attempt to facilitate recall and enhance learning. However, there is a lack of basic research investigating how music carrying information might facilitate recall and subsequent learning. The purpose of the current study was to determine the effects of voice timbre and accompaniment on working memory as measured by recall performance on a sequential digit recall task. Specific research questions were as follows: (a) How might female and male voice timbres affect serial recall? (b) How might piano, guitar, and no accompaniment affect serial recall? (c) Do music majors have enhanced recall accuracy when compared to nonmusic majors? The recall of information paired with six different melodies was tested on 60 university students. Melodies were composed and recorded using female and male voices with three levels of accompaniment: guitar, piano, and no accompaniment. Participants had more accurate recall during the male voice and piano and no accompaniment conditions and least accurate recall during the female voice and guitar accompaniment conditions. As participants had most accurate recall during the male voice and with piano or no accompaniment, clinicians are encouraged to consider using no accompaniment or piano accompaniment when initially teaching social and academic information paired with music for later recall. When possible, vocal timbre (i.e., the potential benefit of male voicing) should also be considered. Implications for clinical practice, limitations of the study, and suggestions for future research are provided. © the American Music Therapy Association 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Performance of the Digital Science Partnership Remotely-Operated 0.5-Meter Corrected Dall-Kirkham Telescopes

    Science.gov (United States)

    Kielkopf, John F.; Carter, B.; Brown, C.; Hart, R.; Hay, J.; Waite, I.

    2007-12-01

    The Digital Science Partnership, a collaboration of the University of Louisville and the University of Southern Queensland, operates a pair of 0.5-meter telescopes for teaching, research, and informal education. The instruments were installed at sites near Toowoomba, Australia, and Louisville, Kentucky in 2006. The Planewave Instruments optical systems employ a unique Dall-Kirkham design incorporating a two-element corrector that demagnifies the image, flattens the focal plane, and reduces coma. These instruments have a moderately fast f/6.8 focal ratio and maintain image quality with little vignetting over a field 42 mm in diameter (0.7 degree). With a 9-micron pixel CCD such as the KAF-6303E, the image scale of 0.55 seconds of arc per pixel typically yields seeing-limited image quality at our sites. The telescopes and their enclosure are operated in a live remote observing mode through Linux-based software, including a dome-control system that uses RFID tags for absolute rotation encoding. After several months of testing and development we have examples of images and photometry from both sites that illustrate the performance of the system. We will discuss image quality, as well as practical matters such as pointing accuracy and field acquisition, auto-guiding, communication latency in large file transfer, and our experience with remote observing assisted by teleconferencing. Time-delay-integration (TDI) imaging, in which the telescope is stationary while the CCD is clocked to track in right ascension, is under study. The technique offers wide fields of view with very high signal-to-noise ratio, and can be implemented in robotically operated instruments used in monitoring, rapid-response, and educational programs. Results for conventional and TDI imaging from the dark site in Australia compared to the brighter suburban site in Kentucky show the benefits of access to dark sites through international partnerships that remote operation technology offers.

  6. Digital power and performance analysis of inkjet printed ring oscillators based on electrolyte-gated oxide electronics

    Science.gov (United States)

    Cadilha Marques, Gabriel; Garlapati, Suresh Kumar; Dehm, Simone; Dasgupta, Subho; Hahn, Horst; Tahoori, Mehdi; Aghassi-Hagmann, Jasmin

    2017-09-01

    Printed electronic components offer certain technological advantages over their silicon based counterparts, like mechanical flexibility, low process temperatures, maskless and additive manufacturing possibilities. However, to be compatible to the fields of smart sensors, Internet of Things, and wearables, it is essential that devices operate at small supply voltages. In printed electronics, mostly silicon dioxide or organic dielectrics with low dielectric constants have been used as gate isolators, which in turn have resulted in high power transistors operable only at tens of volts. Here, we present inkjet printed circuits which are able to operate at supply voltages as low as ≤2 V. Our transistor technology is based on lithographically patterned drive electrodes, the dimensions of which are carefully kept well within the printing resolutions; the oxide semiconductor, the electrolytic insulator and the top-gate electrodes have been inkjet printed. Our inverters show a gain of ˜4 and 2.3 ms propagation delay time at 1 V supply voltage. Subsequently built 3-stage ring oscillators start to oscillate at a supply voltage of only 0.6 V with a frequency of ˜255 Hz and can reach frequencies up to ˜350 Hz at 2 V supply voltage. Furthermore, we have introduced a systematic methodology for characterizing ring oscillators in the printed electronics domain, which has been largely missing. Benefiting from this procedure, we are now able to predict the switching capacitance and driver capability at each stage, as well as the power consumption of our inkjet printed ring oscillators. These achievements will be essential for analyzing the performance and power characteristics of future inkjet printed digital circuits.

  7. Digital control of the performance of reciprocating compressors in industrial refrigeration; Digitale Leistungsregelung fuer Hubkolbenverdichter in der Gewerbekaelte

    Energy Technology Data Exchange (ETDEWEB)

    Kaemmer, Norbert; Tomski, Thomas [Emerson Climate Technologies GmbH, Aachen (Germany); Majer, Igor [Emerson Climate Technologies s.r.o., Mikulov (Czech Republic)

    2011-07-01

    During the past few years, digital continuous control has become the primary control concept for scroll compressors. Recently, it has also been applied to reciprocating compressors. This is an interesting alternative to frequency converters and conventional systems and can also be combined with these. In a test facility that simulates a supermarket, various combinations of output-regulated reciprocating compressors were investigated. The refrigeration performance, electric power consumption and other data were recorded for different stationary load states. The experimental set-up, plant parameters and first results are presented in the contribution. Reliable quality data are not available as yet. Intended further investigations and improvements in the experimental set-up are gone into. [German] Im Bereich der Scrollverdichter hat sich in den letzten Jahren bei Verfluessigungssaetzen und kleineren Verbundanlagen die digitale stufenlose Leistungsregelung etabliert. In diesem Segment kann die Technologie ihre Vorzuege, Einfachheit und geringe zusaetzliche installierte Kosten bezogen auf das Gesamtsystem, am Besten ausspielen. Die digitale Regelung ist nun auch fuer Hubkolbenverdichter verfuegbar. Einerseits bietet sie eine interessante Alternative zu Frequenzumrichtern und herkoemmlichen Entlastungssystemen. Andererseits kann sie auch in Kombination mit diesen Technologien eingesetzt werden. In einer Versuchsanlage, die einen Supermarkt simuliert, wurden verschiedene Kombinationsmoeglichkeiten von leistungsgeregelten Hubkolbenverdichtern untersucht. Dazu wurden fuer verschiedene stationaere Lastzustaende die Kaelteleistung, die elektrische Leistungsaufnahme und andere Anlagenwerte erfasst. Die Versuchsanlage, die untersuchten Anlagenparameter und erste Messergebnisse werden dargestellt. Da die Versuchsanlage und der Versuchsbetrieb noch nicht seinen endgueltigen Reifegrad erreicht hat, koennen noch keine verlaesslichen Anlagenguetegrade vorgestellt werden. Es wird

  8. Becoming digital

    DEFF Research Database (Denmark)

    Pors, Anja Svejgaard

    2015-01-01

    government, and draws on empirical material generated through observations, field notes, interviews and policy documents. The material is documenting how service is performed by frontline agents in the ‘bureaucratic encounter’ with citizens, who needs assistance to use digital self-service in order to apply...... online for a public benefit. Findings: The paper shows that e-government technology changes the mode of professionalism in citizen service from service to support. The paper gives an empirical account of recent Danish digital reforms and shows how the reforms both enable and constrain the work...... of ‘becoming digital’ by frontline agents. Overall the street-level bureaucrat’s classical tasks such as specialized casework are being displaced into promoting and educational tasks. An implication of this is blurred distinctions between professional skills and personal competences of the frontline agent...

  9. Design of a digital beam attenuation system for computed tomography. Part II. Performance study and initial results

    International Nuclear Information System (INIS)

    Szczykutowicz, Timothy P.; Mistretta, Charles A.

    2013-01-01

    Purpose: The purpose of this work is to present a performance study of the digital beam attenuator (DBA) for implementing fluence field modulated CT (FFMCT) using a simulation framework developed to model the incorporation of the DBA into an existing CT system. Additionally, initial results will be presented using a prototype DBA and the realization of the prototype will be described. To our knowledge, this study represents the first experimental use of a device capable of modulating x-ray fluence as a function of fan angle using a CT geometry. Methods: To realize FFMCT, the authors propose to use a wedge design in which one wedge is held stationary and another wedge is moved over the stationary wedge. Due to the wedge shape, the composite thickness of the two wedges changes as a function of the amount of overlap between the wedges. This design allows for the wedges to modulate the photon fluence incident onto a patient. Using a simulation environment, the effect of changing the number of wedges has on dose, scatter, detector dynamic range, and noise uniformity is explored. Experimental results are presented using a prototype DBA having ten Fe wedges and a c-arm CT system geometry. The experimental DBA results are compared to non-DBA scans using scatter and detector dynamic range as metrics. Both flat field and bowtie filtered CT acquisitions were simulated for comparison with the DBA. Results: Numerical results suggest that substantial gains in noise uniformity and scatter-to-primary ratio (SPR) can be obtained using only seven wedges. After seven wedges, the decrease in noise ununiformity and SPR falls off at a lower rate. Simulations comparing CT acquisitions between flat field, bowtie enabled, and DBA CT acquisitions suggest DBA-FFMCT can reduce dose relative to flat field CT by ≈3 times. A bowtie filter under the same imaging conditions was shown to only allow a dose reduction of 1.65 times. Experimentally, a 10 wedge DBA prototype result showed a SPR

  10. Film-screen digital radiography

    International Nuclear Information System (INIS)

    Schwenker, R.P.; Eger, H.

    1985-01-01

    The excellent performance of the digital film-screen system as a receptor for projection radiographic data is discussed. An experimental system for obtaining high quality digital radiographic data by laser scanning radiographic films is described. This system is being used to evaluate the clinical utility of various digital image processing algorithms. Future plans include an investigation of quantitative analysis of projection radiographic data. Digital data obtained by film scanning can be used with digital image archiving and communications systems. (author)

  11. A multilevel analysis of Swedish and Norwegian students’ overall and digital reading performance with a focus on equity aspects of education

    Directory of Open Access Journals (Sweden)

    Maria A. Rasmusson

    2016-02-01

    Full Text Available Abstract Background Influence of external factors in general, and socioeconomic background factors in particular, on traditional reading performance has been extensively researched and debated. While traditional reading is well investigated in this respect, there is a lack of studies on equity aspects related to digital reading achievement, in spite of the fact that time spent on reading from digital devices such as computers, tablets, and smart phones without doubt is increasing all over the world. In the hope of contributing to an area that up until now to a great extent has been left unresearched, the present study aims at investigating to what degree external factors, such as cultural and economic capital, parental pressure, and school choice, are related to 15-year-old students’ achievement in digital reading and in overall reading on both the student level and the school level in Norway and Sweden. Methods To conduct the analysis, multilevel structural modeling techniques have been used on PISA data from the two countries. Results The results for the Norwegian as well as for the Swedish sample showed that overall reading achievement was related to cultural capital in both countries, as expected, and in line with previous research. An identified digital reading factor, representing the unique aspects of digital reading achievement when overall reading was controlled for, was less influenced by the external factors of cultural and economic capital, and by parental pressure and school type, compared to performance in overall reading. Interestingly, on the school level, it was found that the external factors, school choice, and parental pressure related to overall reading achievement differently in the Norwegian and Swedish samples. School choice influenced overall reading in the Swedish data but not in the Norwegian data, and the opposite pattern was found for parental pressure. Conclusion In conclusion, it is suggested that the results

  12. Observer Performance in the Use of Digital and Optical Microscopy for the Interpretation of Tissue-Based Biomarkers

    Directory of Open Access Journals (Sweden)

    Marios A. Gavrielides

    2014-01-01

    Full Text Available Background. We conducted a validation study of digital pathology for the quantitative assessment of tissue-based biomarkers with immunohistochemistry. Objective.\tTo examine observer agreement as a function of viewing modality (digital versus optical microscopy, whole slide versus tissue microarray (TMA review, biomarker type (HER2 incorporating membranous staining and Ki-67 with nuclear staining, and data type (continuous and categorical. Methods.\tEight pathologists reviewed 50 breast cancer whole slides (25 stained with HER2 and 25 with Ki-67 and 2 TMAs (1 stained with HER2, 1 with Ki-67, each containing 97 cores, using digital and optical microscopy. Results. Results showed relatively high overall interobserver and intermodality agreement, with different patterns specific to biomarker type. For HER2, there was better interobserver agreement for optical compared to digital microscopy for whole slides as well as better interobserver and intermodality agreement for TMAs. For Ki-67, those patterns were not observed. Conclusions. The differences in agreement patterns when examining different biomarkers and different scoring methods and reviewing whole slides compared to TMA stress the need for validation studies focused on specific pathology tasks to eliminate sources of variability that might dilute findings. The statistical uncertainty observed in our analyses calls for adequate sampling for each individual task rather than pooling cases.

  13. Imaging performance of LabPET APD-based digital PET scanners for pre-clinical research

    International Nuclear Information System (INIS)

    Bergeron, Mélanie; Cadorette, Jules; Beaudoin, Jean-François; Lecomte, Roger; Tétrault, Marc-André; Leroux, Jean-Daniel; Fontaine, Réjean

    2014-01-01

    The LabPET is an avalanche photodiode (APD) based digital PET scanner with quasi-individual detector read-out and highly parallel electronic architecture for high-performance in vivo molecular imaging of small animals. The scanner is based on LYSO and LGSO scintillation crystals (2×2×12/14 mm 3 ), assembled side-by-side in phoswich pairs read out by an APD. High spatial resolution is achieved through the individual and independent read-out of an individual APD detector for recording impinging annihilation photons. The LabPET exists in three versions, LabPET4 (3.75 cm axial length), LabPET8 (7.5 cm axial length) and LabPET12 (11.4 cm axial length). This paper focuses on the systematic characterization of the three LabPET versions using two different energy window settings to implement a high-efficiency mode (250–650 keV) and a high-resolution mode (350–650 keV) in the most suitable operating conditions. Prior to measurements, a global timing alignment of the scanners and optimization of the APD operating bias have been carried out. Characteristics such as spatial resolution, absolute sensitivity, count rate performance and image quality have been thoroughly investigated following the NEMA NU 4-2008 protocol. Phantom and small animal images were acquired to assess the scanners' suitability for the most demanding imaging tasks in preclinical biomedical research. The three systems achieve the same radial FBP spatial resolution at 5 mm from the field-of-view center: 1.65/3.40 mm (FWHM/FWTM) for an energy threshold of 250 keV and 1.51/2.97 mm for an energy threshold of 350 keV. The absolute sensitivity for an energy window of 250–650 keV is 1.4%/2.6%/4.3% for LabPET4/8/12, respectively. The best count rate performance peaking at 362 kcps is achieved by the LabPET12 with an energy window of 250–650 keV and a mouse phantom (2.5 cm diameter) at an activity of 2.4 MBq ml −1 . With the same phantom, the scatter fraction for all scanners is about

  14. Quality assurance in digital radiography

    International Nuclear Information System (INIS)

    Busch, H.P.; Lehmann, K.J.

    1989-01-01

    At present, there is no standard way of evaluating performance characteristics of digital radiography systems. Continuous measurements of performance parameters are necessary in order to obtain images of high quality. Parameters of quality assurance in digital radiography, which can be evaluated with simple, quick methods, are spatial resolution, low-contrast detectability, dynamic range and exposure dose. Spatial resolution was determined by a lead bar pattern, whereas the other parameters were measured by commercially available phantoms. Performance measurements of 10 digital subtraction angiography (DSA) units and one digital radiography system for unsubtracted digital radiography were assessed. From these results, recommendations for performance parameter levels will be discussed. (author)

  15. Analysis of the performance and usefulness of a new digital gamma camera and short-lived radionuclide Au-195m for cardiac studies

    International Nuclear Information System (INIS)

    Mena, I.; Amaral, H.; Adams, R.; Garcia, E.; de Jong, R.

    1983-01-01

    The purpose of this investigation is to evaluate at LAC Harbor-UCLA Medical Center dead time characteristics of the digital camera Elscint (Apex 415), designed by the manufacturer to improve the count rate performance, its resolution and clinical applications in first pass ventriculography. The Hg-195m/Au-195m generator is evaluated for Hg-195 leakage, dosimetry and clinical usefulness. The high count rate capability of the digital camera is maximally utilized in biplane ventriculography which may become the optimal modality for dynamic cardiovascular nuclear medicine studies. The resolution achieved in this high count rate modality appears perfectly adequate for high quality studies. The imaging and radiation exposure characteristics of the 30.5 sec half life Au 195m are promising of a significant clinical contribution in the field of adult and pediatric cardiology

  16. Replacing single-view mediolateral oblique (MLO) digital mammography (DM) with synthesized mammography (SM) with digital breast tomosynthesis (DBT) images: Comparison of the diagnostic performance and radiation dose with two-view DM with or without MLO-DBT

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyo-Jin [Department of Radiology, Seoul National University Hospital, 03080 (Korea, Republic of); Chang, Jung Min, E-mail: imchangjm@gmail.com [Department of Radiology, Seoul National University Hospital, 03080 (Korea, Republic of); Department of Radiology, Seoul National University College of Medicine, 03080 (Korea, Republic of); Lee, Joongyub [Medical Research Collaborating Center, Biomedical Research Institution, Seoul National University Hospital, 03080 (Korea, Republic of); Song, Sung Eun; Shin, Sung Ui [Department of Radiology, Seoul National University Hospital, 03080 (Korea, Republic of); Kim, Won Hwa [Department of Radiology, Kyungpook National University Hospital, 41944 (Korea, Republic of); Bae, Min Sun [Department of Radiology, Seoul National University Hospital, 03080 (Korea, Republic of); Moon, Woo Kyung [Department of Radiology, Seoul National University Hospital, 03080 (Korea, Republic of); Department of Radiology, Seoul National University College of Medicine, 03080 (Korea, Republic of); Institute of Radiation Medicine, Seoul National University College Medical Research Center, 03080 (Korea, Republic of)

    2016-11-15

    Objectives: To evaluate the diagnostic performance and radiation dose of single view cranio-caudal (CC) digital mammography (DM) plus mediolateral oblique (MLO) digital breast tomosynthesis (DBT) combined with synthesized mammography (SM) in comparison with two-view DM with or without DBT. Material and methods: This study was approved by our institutional review board, and informed consent was obtained from 130 women. Paired two-view DM and single MLO-DBT with SM images were acquired, and four independent retrospective reading sessions of different combinations of DM, SM and DBT were performed for the presence of malignant tumors using jackknife alternative free-response receiver operator curve (JAFROC) methods. The diagnostic performances and average glandular dose (AGD) were compared between different combinations of DM, SM and DBT. Results: Of 159 lesions in 130 patients, 27 were malignant. When using MLO-DBT with SM instead of MLO-DM, a significantly higher sensitivity (P = 0.016) and specificity (P = 0.012) were noted than with two-view DM, and comparable figure of merit (FOM), sensitivity, and specificity to two-view DM with DBT were noted. The mean AGD of CC-DM plus MLO-DBT with SM was 5.78mGy ± 1.06 per patient, which was significantly lower than that with two-view DM with MLO-DBT (8.45mGy ± 1.32; P <0.001) and slightly higher than that with two-view DM (5.30mGy ± 0.63). Conclusions: The combined use of CC-DM plus MLO-DBT with SM showed higher sensitivity and specificity to two-view DM with a smaller AGD increment and comparable diagnostic performance to that of two-view DM with MLO-DBT with a significantly lower mean AGD.

  17. Experimental investigation of analog and digital dimming techniques on photometric performance of an indoor Visible Light Communication (VLC) system

    Science.gov (United States)

    Zafar, Fahad; Kalavally, Vineetha; Bakaul, Masuduzzaman; Parthiban, R.

    2015-09-01

    For making commercial implementation of light emitting diode (LED) based visible light communication (VLC) systems feasible, it is necessary to incorporate it with dimming schemes which will provide energy savings, moods and increase the aesthetic value of the places using this technology. There are two general methods which are used to dim LEDs commonly categorized as analog and digital dimming. Incorporating fast data transmission with these techniques is a key challenge in VLC. In this paper, digital and analog dimming for a 10 Mb/s non return to zero on-off keying (NRZ-OOK) based VLC system is experimentally investigated considering both photometric and communicative parameters. A spectrophotometer was used for photometric analysis and a line of sight (LOS) configuration in the presence of ambient light was used for analyzing communication parameters. Based on the experimental results, it was determined that digital dimming scheme is preferable for use in indoor VLC systems requiring high dimming precision and data transmission at lower brightness levels. On the other hand, analog dimming scheme is a cost effective solution for high speed systems where dimming precision is insignificant.

  18. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Johnsen, Karen Kirstine; Thomsen, Henrik

    on collimation and dose reduction in digital chest radiography Methods and Materials A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from one hundred fifty self-reliant female patients between 15 and 55 years...

  19. Digital radiography

    International Nuclear Information System (INIS)

    Brody, W.R.

    1984-01-01

    Digital Radiography begins with an orderly introduction to the fundamental concepts of digital imaging. The entire X-ray digital imagining system is described, from an overall characterization of image quality to specific components required for a digital radiographic system. Because subtraction is central to digital radiographic systems, the author details the use of various subtraction methods for image enhancement. Complex concepts are illustrated with numerous examples and presented in terms that can readily be understood by physicians without an advanced mathematics background. The second part of the book discusses implementations and applications of digital imagining systems based on area and scanned detector technologies. This section includes thorough coverage of digital fluoroscopy, scanned projection radiography, and film-based digital imaging systems, and features a state-of-the-art synopsis of the applications of digital subtraction angiography. The book concludes with a timely assessment of anticipated technological advances

  20. Digital Culture and Digital Library

    Directory of Open Access Journals (Sweden)

    Yalçın Yalçınkaya

    2016-12-01

    Full Text Available In this study; digital culture and digital library which have a vital connection with each other are examined together. The content of the research consists of the interaction of culture, information, digital culture, intellectual technologies, and digital library concepts. The study is an entry work to integrity of digital culture and digital library theories and aims to expand the symmetry. The purpose of the study is to emphasize the relation between the digital culture and digital library theories acting intersection of the subjects that are examined. Also the perspective of the study is based on examining the literature and analytical evaluation in both studies (digital culture and digital library. Within this context, the methodology of the study is essentially descriptive and has an attribute for the transmission and synthesis of distributed findings produced in the field of the research. According to the findings of the study results, digital culture is an inclusive term that describes the effects of intellectual technologies in the field of information and communication. Information becomes energy and the spectrum of the information is expanding in the vertical rise through the digital culture. In this context, the digital library appears as a new living space of a new environment. In essence, the digital library is information-oriented; has intellectual technology support and digital platform; is in a digital format; combines information resources and tools in relationship/communication/cooperation by connectedness, and also it is the dynamic face of the digital culture in time and space independence. Resolved with the study is that the digital libraries are active and effective in the formation of global knowing and/or mass wisdom in the process of digital culture.

  1. Digital gaming expertise

    DEFF Research Database (Denmark)

    Toft-Nielsen, Claus

    In a digitally saturated environment digital media users of all kinds, engaged in different areas of activity, are increasingly categorized in terms of their ability to appropriate and use digital media – they are regarded as non-users, experts, natives, or literates for instance. Within communic......In a digitally saturated environment digital media users of all kinds, engaged in different areas of activity, are increasingly categorized in terms of their ability to appropriate and use digital media – they are regarded as non-users, experts, natives, or literates for instance. Within...... communication and game studies there are multiple understandings of how digital expertise is expressed and performed, and subsequently how these expressions and performances can be valued, understood and theorized within the research community. Among other things expertise with and within digital games has......-of-game (Schrøder, 2003) in a three-year-long study of men and women (couples and singles) playing the largest Massively Multiplayer Online Role-Playing Game to date, World of Warcraft. In focusing on how different aspects of gaming expertise are articulated, negotiated, and performed, I aim to illustrate how...

  2. Twenty-fifth water reactor safety information meeting: Proceedings. Volume 3: Thermal hydraulic research and codes; Digital instrumentation and control; Structural performance

    International Nuclear Information System (INIS)

    Monteleone, S.

    1998-04-01

    This three-volume report contains papers presented at the conference. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Japan, Norway, and Russia. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. This volume contains the following: (1) thermal hydraulic research and codes; (2) digital instrumentation and control; (3) structural performance

  3. Digital mammography; Mamografia digital

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier, M.; Torres, R.

    2010-07-01

    Mammography represents one of the most demanding radiographic applications, simultaneously requiring excellent contrast sensitivity, high spatial resolution, and wide dynamic range. Film/screen is the most widely extended image receptor in mammography due to both its high spatial resolution and contrast. The film/screen limitations are related with its narrow latitude, structural noise and that is at the same time the medium for the image acquisition, storage and presentation. Several digital detector made with different technologies can overcome these difficulties. Here, these technologies as well as their main advantages and disadvantages are analyzed. Also it is discussed its impact on the mammography examinations, mainly on the breast screening programs. (Author).

  4. Design and image-quality performance of high resolution CMOS-based X-ray imaging detectors for digital mammography

    Science.gov (United States)

    Cha, B. K.; Kim, J. Y.; Kim, Y. J.; Yun, S.; Cho, G.; Kim, H. K.; Seo, C.-W.; Jeon, S.; Huh, Y.

    2012-04-01

    In digital X-ray imaging systems, X-ray imaging detectors based on scintillating screens with electronic devices such as charge-coupled devices (CCDs), thin-film transistors (TFT), complementary metal oxide semiconductor (CMOS) flat panel imagers have been introduced for general radiography, dental, mammography and non-destructive testing (NDT) applications. Recently, a large-area CMOS active-pixel sensor (APS) in combination with scintillation films has been widely used in a variety of digital X-ray imaging applications. We employed a scintillator-based CMOS APS image sensor for high-resolution mammography. In this work, both powder-type Gd2O2S:Tb and a columnar structured CsI:Tl scintillation screens with various thicknesses were fabricated and used as materials to convert X-ray into visible light. These scintillating screens were directly coupled to a CMOS flat panel imager with a 25 × 50 mm2 active area and a 48 μm pixel pitch for high spatial resolution acquisition. We used a W/Al mammographic X-ray source with a 30 kVp energy condition. The imaging characterization of the X-ray detector was measured and analyzed in terms of linearity in incident X-ray dose, modulation transfer function (MTF), noise-power spectrum (NPS) and detective quantum efficiency (DQE).

  5. Evaluation of the clinical performance by using the effective DQE for a prototype digital breast tomosynthesis system

    International Nuclear Information System (INIS)

    Choi, Jae-Gu; Choi, Young-Wook; Ham, Tae-Hee; Kim, Ye-Seul; Park, Hye-Suk; Kim, Hee-Joung

    2012-01-01

    Early experience with the application of tomosynthesis to breast imaging has shown the potential of digital breast tomosynthesis (DBT), which can improve the specificity of mammography with improved marginal visibility of the lesion and early breast cancer detection, especially for women with dense breasts. The purpose of this study is to characterize the physical properties of the DBT system and to optimize the exposure conditions by using the modulation transfer function (MTF), the noise power spectrum (NPS), the scatter fraction, the transmission fraction and the effective detective quantum efficiency (eDQE) for different breast thicknesses. The first-generation KERI prototype digital tomosynthesis system for breast imaging using a CMOS flat panel detector was used in this study. The spatial frequency depend on metrics depend on both the inherent properties of the detector and the imaging geometry including breast thickness. For a thicker breast, the eDQE decreases as the scatter fraction increases at a fixed tube voltage. Moreover, the MTF shows no significant difference with changing tube voltage while the eDQE at 27 kVp is slightly degraded. Consequently, the above critical properties of the DBT system for different exposure conditions and breast thicknesses should be fully considered before building the system and using it application in clinical applications.

  6. Developments in gamma-ray spectrometry: systems, software, and methods-II. 4. High-Performance Digital Gamma-Ray Spectrometry

    International Nuclear Information System (INIS)

    Michael Momayezi

    2001-01-01

    use is to correct for the effect of varying charge collection times when measuring gamma-ray energies using large-volume Ge detectors. The substantial charge collection times in a large Ge detector cause ballistic deficit when used with a resistive feedback preamplifier. Conventional Gaussian shaping with long time constants can reduce the resulting spectral broadening to an insignificant level at the great expense of limiting the high count rate capability of a big Ge detector. Pulse shape analysis can be used to accurately correct for the preamplifier ballistic deficit independent of the filter time. As a result, the energy resolution of a big Ge detector at high count rates will be degraded only by the noise performance of its preamplifier. Pulse rise time analysis can be fruitfully applied to hemispherical CdZnTe detectors with a small charge-collecting electrode. In CdZnTe electrons travel fast and are collected with good efficiency over appreciable distances. Holes, on the other hand, travel slowly and are collected with poor efficiency. Hemispherical detectors use the small-pixel effect to reduce their intrinsic sensitivity to this effect. Yet, a pulse rise time analysis can provide a significant improvement in spectral resolution by eliminating events in which the gamma ray converts close to the collecting electrode. Finally, pulse rise time analysis can be used to implement an extremely efficient pileup rejecter, with an equivalent double pulse resolution much less than the trigger filter time or the sampling time of the wave form digitizer. (authors)

  7. Digital Tectonics

    DEFF Research Database (Denmark)

    Christiansen, Karl; Borup, Ruben; Søndergaard, Asbjørn

    2014-01-01

    Digital Tectonics treats the architectonical possibilities in digital generation of form and production. The publication is the first volume of a series, in which aspects of the strategic focus areas of the Aarhus School of Architecture will be disseminated.......Digital Tectonics treats the architectonical possibilities in digital generation of form and production. The publication is the first volume of a series, in which aspects of the strategic focus areas of the Aarhus School of Architecture will be disseminated....

  8. Digital squares

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Kim, Chul E

    1988-01-01

    Digital squares are defined and their geometric properties characterized. A linear time algorithm is presented that considers a convex digital region and determines whether or not it is a digital square. The algorithm also determines the range of the values of the parameter set of its preimages....... The analysis involves transforming the boundary of a digital region into parameter space of slope and y-intercept...

  9. Digital skrivedidaktik

    DEFF Research Database (Denmark)

    Digital skrivedidaktik består af to dele. Første del præsenterer teori om skrivekompetence og digital skrivning. Digital skrivning er karakteriseret ved at tekster skrives på computer og med digitale værktøjer, hvilket ændrer skrivningens traditionelle praksis, produkt og processer. Hvad er digital...... om elevens skriveproces) og Blogskrivning (der styrker eleverne i at bruge blogs i undervisningen)....

  10. Digital signature feasibility study

    Science.gov (United States)

    2008-06-01

    The purpose of this study was to assess the advantages and disadvantages of using digital signatures to assist the Arizona Department of Transportation in conducting business. The Department is evaluating the potential of performing more electronic t...

  11. Digital Citizenship

    Science.gov (United States)

    Isman, Aytekin; Canan Gungoren, Ozlem

    2014-01-01

    Era in which we live is known and referred as digital age.In this age technology is rapidly changed and developed. In light of these technological advances in 21st century, schools have the responsibility of training "digital citizen" as well as a good citizen. Digital citizens must have extensive skills, knowledge, Internet and …

  12. Introduction to digital communication systems

    CERN Document Server

    Wesolowski, Krzysztof

    2009-01-01

    Combining theoretical knowledge and practical applications, this advanced-level textbook covers the most important aspects of contemporary digital communication systems. Introduction to Digital Communication Systems focuses on the rules of functioning digital communication system blocks, starting with the performance limits set by the information theory. Drawing on information relating to turbo codes and LDPC codes, the text presents the basic methods of error correction and detection, followed by baseband transmission methods, and single- and multi-carrier digital modulations. The basi

  13. SHDAS Production Digitizer Evaluation.

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Bion J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    The Seismo-Hydroacoustic Data Acquisition System (SHDAS) is undergoing evaluation in preparation for its engineering, development, and deployment by the U.S Navy as an ocean bottom seismic monitoring system. At the current stage of development, the production digitizers are being evaluated to confirm their performance prior to packaging and assembly for deployment. The testing of the digitizers is being conducted at Delta Group Electronics, the digitizer fabricator, in San Diego, California, performed by Sandia National Laboratories with the assistance of Leidos and Delta Group Electronics.

  14. On the comparison of analog and digital SiPM readout in terms of expected timing performance

    International Nuclear Information System (INIS)

    Gundacker, S.; Auffray, E.; Jarron, P.; Meyer, T.; Lecoq, P.

    2015-01-01

    In time of flight positron emission tomography (TOF-PET) and in particular for the EndoTOFPET-US Project (Frisch, 2013 [1]), and other applications for high energy physics, the multi-digital silicon photomultiplier (MD-SiPM) was recently proposed (Mandai and Charbon, 2012 [2]), in which the time of every single photoelectron is being recorded. If such a photodetector is coupled to a scintillator, the largest and most accurate timing information can be extracted from the cascade of the scintillation photons, and the most probable time of positron emission determined. The readout concept of the MD-SiPM is very different from that of the analog SiPM, where the individual photoelectrons are merely summed up and the output signal fed into the readout electronics. We have developed a comprehensive Monte Carlo (MC) simulation tool that describes the timing properties of the photodetector and electronics, the scintillation properties of the crystal and the light transfer within the crystal. In previous studies we have compared MC simulations with coincidence time resolution (CTR) measurements and found good agreement within less than 10% for crystals of different lengths (from 3 mm to 20 mm) coupled to SiPMs from Hamamatsu. In this work we will use the developed MC tool to directly compare the highest possible time resolution for both the analog and digital readout of SiPMs with different scintillator lengths. The presented studies reveal that the analog readout of SiPMs with microcell signal pile-up and leading edge discrimination can lead to nearly the same time resolution as compared to the maximum likelihood time estimation applied to MD-SiPMs. Consequently there is no real preference for either a digital or analog SiPM for the sake of achieving highest time resolution. However, the best CTR in the analog SiPM is observed for a rather small range of optimal threshold values, whereas the MD-SiPM provides stable CTR after roughly 20 registered photoelectron timestamps in

  15. Digital subtraktion

    DEFF Research Database (Denmark)

    Mussmann, Bo Redder

    2004-01-01

    Digital subtraktion er en metode til at fjerne uønskede oplysninger i et røntgenbillede. Subtraktionsteknikken bruges primært i forbindelse med angiografi hvor man kun er interesseret i at se selve karret. Derfor er digital subtraktion i daglig tale synonymt med DSA eller DVI – hhv. Digital...... Subtraction Angiography eller Digital Vascular Imaging. Benævnelserne er to røntgenfirmaers navn for den samme teknik. Digital subtraktion kræver speciel software, samt at apparaturet kan eksponere i serier....

  16. Digital preservation

    CERN Document Server

    Deegan, Marilyn

    2013-01-01

    Digital preservation is an issue of huge importance to the library and information profession right now. With the widescale adoption of the internet and the rise of the world wide web, the world has been overwhelmed by digital information. Digital data is being produced on a massive scale by individuals and institutions: some of it is born, lives and dies only in digital form, and it is the potential death of this data, with its impact on the preservation of culture, that is the concern of this book. So how can information professionals try to remedy this? Digital preservation is a complex iss

  17. Digital Natives or Digital Tribes?

    Science.gov (United States)

    Watson, Ian Robert

    2013-01-01

    This research builds upon the discourse surrounding digital natives. A literature review into the digital native phenomena was undertaken and found that researchers are beginning to identify the digital native as not one cohesive group but of individuals influenced by other factors. Primary research by means of questionnaire survey of technologies…

  18. Source-gated transistors for order-of-magnitude performance improvements in thin-film digital circuits

    Science.gov (United States)

    Sporea, R. A.; Trainor, M. J.; Young, N. D.; Shannon, J. M.; Silva, S. R. P.

    2014-03-01

    Ultra-large-scale integrated (ULSI) circuits have benefited from successive refinements in device architecture for enormous improvements in speed, power efficiency and areal density. In large-area electronics (LAE), however, the basic building-block, the thin-film field-effect transistor (TFT) has largely remained static. Now, a device concept with fundamentally different operation, the source-gated transistor (SGT) opens the possibility of unprecedented functionality in future low-cost LAE. With its simple structure and operational characteristics of low saturation voltage, stability under electrical stress and large intrinsic gain, the SGT is ideally suited for LAE analog applications. Here, we show using measurements on polysilicon devices that these characteristics lead to substantial improvements in gain, noise margin, power-delay product and overall circuit robustness in digital SGT-based designs. These findings have far-reaching consequences, as LAE will form the technological basis for a variety of future developments in the biomedical, civil engineering, remote sensing, artificial skin areas, as well as wearable and ubiquitous computing, or lightweight applications for space exploration.

  19. Evaluation of the performance of quantitative detection of the Listeria monocytogenes prfA locus with droplet digital PCR.

    Science.gov (United States)

    Witte, Anna Kristina; Fister, Susanne; Mester, Patrick; Schoder, Dagmar; Rossmanith, Peter

    2016-11-01

    Fast and reliable pathogen detection is an important issue for human health. Since conventional microbiological methods are rather slow, there is growing interest in detection and quantification using molecular methods. The droplet digital polymerase chain reaction (ddPCR) is a relatively new PCR method for absolute and accurate quantification without external standards. Using the Listeria monocytogenes specific prfA assay, we focused on the questions of whether the assay was directly transferable to ddPCR and whether ddPCR was suitable for samples derived from heterogeneous matrices, such as foodstuffs that often included inhibitors and a non-target bacterial background flora. Although the prfA assay showed suboptimal cluster formation, use of ddPCR for quantification of L. monocytogenes from pure bacterial cultures, artificially contaminated cheese, and naturally contaminated foodstuff was satisfactory over a relatively broad dynamic range. Moreover, results demonstrated the outstanding detection limit of one copy. However, while poorer DNA quality, such as resulting from longer storage, can impair ddPCR, internal amplification control (IAC) of prfA by ddPCR, that is integrated in the genome of L. monocytogenes ΔprfA, showed even slightly better quantification over a broader dynamic range. Graphical Abstract Evaluating the absolute quantification potential of ddPCR targeting Listeria monocytogenes prfA.

  20. Digital mammography

    International Nuclear Information System (INIS)

    Bick, Ulrich; Diekmann, Felix

    2010-01-01

    This state-of-the-art reference book provides in-depth coverage of all aspects of digital mammography, including detector technology, image processing, computer-aided diagnosis, soft-copy reading, digital workflow, and PACS. Specific advantages and disadvantages of digital mammography in comparison to screen-film mammography are thoroughly discussed. By including authors from both North America and Europe, the book is able to outline variations in the use, acceptance, and quality assurance of digital mammography between the different countries and screening programs. Advanced imaging techniques and future developments such as contrast mammography and digital breast tomosynthesis are also covered in detail. All of the chapters are written by internationally recognized experts and contain numerous high-quality illustrations. This book will be of great interest both to clinicians who already use or are transitioning to digital mammography and to basic scientists working in the field. (orig.)

  1. Digital Insights

    DEFF Research Database (Denmark)

    Knudsen, Gry Høngsmark

    , by incorporating media as both channel, frame, and apparatus for advertising response, the dissertation brings into attention that more aspects than the text-reader relationship influence ad response. Finally, the dissertation proposes the assemblage approach for exploring big data in consumer culture research...... and practices with digital media, when they meet and interpret advertising. Through studies of advertising response on YouTube and experiments with consumers’ response to digitally manipulated images, the dissertation shows how digital media practices facilitate polysemic and socially embedded advertising......This dissertation forwards the theory of digital consumer-response as a perspective to examine how digital media practices influence consumers’ response to advertising. Digital consumer-response is a development of advertising theory that encompasses how consumers employ their knowledge...

  2. Digital divide among people with disabilities: Analysis of data from a nationwide study for determinants of Internet use and activities performed online.

    Science.gov (United States)

    Duplaga, Mariusz

    2017-01-01

    The Internet is both an opportunity as well as a challenge for people with disabilities. However, this segment of the population is usually indicated among social groups experiencing digital divide. The study is focused on the analysis of factors determining Internet usage and undertaking specific activities online among people with disabilities based on a nationwide study performed in 2013 in Poland. Secondary analysis was performed on the data of persons who declared disability status in 2013 "Social Diagnosis" study. Multivariate logistic regression models were developed for the use of the Internet and performing three types of activities online. Among 3,556 respondents with disability 51.02% were females, 25.19% 65 years of age and over and 33.05% were Internet users. The predictors of Internet usage included the degree of disability, place of residence, level of education, marital status, occupational status, net income, use of health care service and the use of mobile phone. The odds ratio that a person with disability belonging to the oldest category will use the Internet was only 0.04 (95% CI 0.02-0.09), when compared to the youngest category. The odds that a person with disability from the highest category of education will use the Internet were 18 times higher than in the case of persons with only basic education (OR 18.17, 95% CI 11.70-28.21). Common predictors of online activities (accessing websites of public institutions, checking and sending emails, publishing own content on the Internet) included age category and net income. People with disabilities in Poland are facing a significant digital divide. The factors determining the use of the Internet in this group are similar to those of the general population. On the other hand, people with disabilities who are active online, access diversified types of services including presentation of their own content online.

  3. Digital divide among people with disabilities: Analysis of data from a nationwide study for determinants of Internet use and activities performed online.

    Directory of Open Access Journals (Sweden)

    Mariusz Duplaga

    Full Text Available The Internet is both an opportunity as well as a challenge for people with disabilities. However, this segment of the population is usually indicated among social groups experiencing digital divide. The study is focused on the analysis of factors determining Internet usage and undertaking specific activities online among people with disabilities based on a nationwide study performed in 2013 in Poland.Secondary analysis was performed on the data of persons who declared disability status in 2013 "Social Diagnosis" study. Multivariate logistic regression models were developed for the use of the Internet and performing three types of activities online.Among 3,556 respondents with disability 51.02% were females, 25.19% 65 years of age and over and 33.05% were Internet users. The predictors of Internet usage included the degree of disability, place of residence, level of education, marital status, occupational status, net income, use of health care service and the use of mobile phone. The odds ratio that a person with disability belonging to the oldest category will use the Internet was only 0.04 (95% CI 0.02-0.09, when compared to the youngest category. The odds that a person with disability from the highest category of education will use the Internet were 18 times higher than in the case of persons with only basic education (OR 18.17, 95% CI 11.70-28.21. Common predictors of online activities (accessing websites of public institutions, checking and sending emails, publishing own content on the Internet included age category and net income.People with disabilities in Poland are facing a significant digital divide. The factors determining the use of the Internet in this group are similar to those of the general population. On the other hand, people with disabilities who are active online, access diversified types of services including presentation of their own content online.

  4. Digital Signage

    OpenAIRE

    Fischer, Karl Peter

    2011-01-01

    Digital Signage for in-store advertising at gas stations/retail stores in Germany: A field study Digital Signage networks provide a novel means of advertising with the advantage of easily changeable and highly customizable animated content. Despite the potential and increasing use of these media empirical research is scarce. In a field study at 8 gas stations (with integrated convenience stores) we studied the effect of digital signage advertising on sales for different products and servi...

  5. Digital printing

    Science.gov (United States)

    Sobotka, Werner K.

    1997-02-01

    Digital printing is described as a tool to replace conventional printing machines completely. Still this goal was not reached until now with any of the digital printing technologies to be described in the paper. Productivity and costs are still the main parameters and are not really solved until now. Quality in digital printing is no problem anymore. Definition of digital printing is to transfer digital datas directly on the paper surface. This step can be carried out directly or with the use of an intermediate image carrier. Keywords in digital printing are: computer- to-press; erasable image carrier; image carrier with memory. Digital printing is also the logical development of the new digital area as it is pointed out in Nicholas Negropotes book 'Being Digital' and also the answer to networking and Internet technologies. Creating images text and color in one country and publishing the datas in another country or continent is the main advantage. Printing on demand another big advantage and last but not least personalization the last big advantage. Costs and being able to coop with this new world of prepress technology is the biggest disadvantage. Therefore the very optimistic growth rates for the next few years are really nonexistent. The development of complete new markets is too slow and the replacing of old markets is too small.

  6. Recognition of tennis serve performed by a digital player: comparison among polygon, shadow, and stick-figure models.

    Directory of Open Access Journals (Sweden)

    Hirofumi Ida

    Full Text Available The objective of this study was to assess the cognitive effect of human character models on the observer's ability to extract relevant information from computer graphics animation of tennis serve motions. Three digital human models (polygon, shadow, and stick-figure were used to display the computationally simulated serve motions, which were perturbed at the racket-arm by modulating the speed (slower or faster of one of the joint rotations (wrist, elbow, or shoulder. Twenty-one experienced tennis players and 21 novices made discrimination responses about the modulated joint and also specified the perceived swing speeds on a visual analogue scale. The result showed that the discrimination accuracies of the experienced players were both above and below chance level depending on the modulated joint whereas those of the novices mostly remained at chance or guessing levels. As far as the experienced players were concerned, the polygon model decreased the discrimination accuracy as compared with the stick-figure model. This suggests that the complicated pictorial information may have a distracting effect on the recognition of the observed action. On the other hand, the perceived swing speed of the perturbed motion relative to the control was lower for the stick-figure model than for the polygon model regardless of the skill level. This result suggests that the simplified visual information can bias the perception of the motion speed toward slower. It was also shown that the increasing the joint rotation speed increased the perceived swing speed, although the resulting racket velocity had little correlation with this speed sensation. Collectively, observer's recognition of the motion pattern and perception of the motion speed can be affected by the pictorial information of the human model as well as by the perturbation processing applied to the observed motion.

  7. Recognition of tennis serve performed by a digital player: comparison among polygon, shadow, and stick-figure models.

    Science.gov (United States)

    Ida, Hirofumi; Fukuhara, Kazunobu; Ishii, Motonobu

    2012-01-01

    The objective of this study was to assess the cognitive effect of human character models on the observer's ability to extract relevant information from computer graphics animation of tennis serve motions. Three digital human models (polygon, shadow, and stick-figure) were used to display the computationally simulated serve motions, which were perturbed at the racket-arm by modulating the speed (slower or faster) of one of the joint rotations (wrist, elbow, or shoulder). Twenty-one experienced tennis players and 21 novices made discrimination responses about the modulated joint and also specified the perceived swing speeds on a visual analogue scale. The result showed that the discrimination accuracies of the experienced players were both above and below chance level depending on the modulated joint whereas those of the novices mostly remained at chance or guessing levels. As far as the experienced players were concerned, the polygon model decreased the discrimination accuracy as compared with the stick-figure model. This suggests that the complicated pictorial information may have a distracting effect on the recognition of the observed action. On the other hand, the perceived swing speed of the perturbed motion relative to the control was lower for the stick-figure model than for the polygon model regardless of the skill level. This result suggests that the simplified visual information can bias the perception of the motion speed toward slower. It was also shown that the increasing the joint rotation speed increased the perceived swing speed, although the resulting racket velocity had little correlation with this speed sensation. Collectively, observer's recognition of the motion pattern and perception of the motion speed can be affected by the pictorial information of the human model as well as by the perturbation processing applied to the observed motion.

  8. Effects of integrated designs of alarm and process information on diagnosis performance in digital nuclear power plants.

    Science.gov (United States)

    Wu, Xiaojun; She, Manrong; Li, Zhizhong; Song, Fei; Sang, Wei

    2017-12-01

    In the main control rooms of nuclear power plants (NPPs), operators frequently switch between alarm displays and system-information displays to incorporate information from different screens. In this study, we investigated two integrated designs of alarm and process information - integrating alarm information into process displays (denoted as Alarm2Process integration) and integrating process information into alarm displays (denoted as Process2Alarm integration). To analyse the effects of the two integration approaches and time pressure on the diagnosis performance, a laboratory experiment was conducted with ninety-six students. The results show that compared with the non-integrated case, Process2Alarm integration yields better diagnosis performance in terms of diagnosis accuracy, time required to generate correct hypothesis and completion time. In contrast, the Alarm2Process integration leads to higher levels of workload, with no improvement in diagnosis performance. The diagnosis performance of Process2Alarm integration was consistently better than that of Alarm2Process integration, regardless of the levels of time pressure. Practitioner Summary: To facilitate operator's synthesis of NPP information when performing diagnosis tasks, we proposed to integrate process information into alarm displays. The laboratory validation shows that the integration approach significantly improves the diagnosis performance for both low and high time-pressure levels.

  9. An Electronic Workshop on the Performance Seeking Control and Propulsion Controlled Aircraft Results of the F-15 Highly Integrated Digital Electronic Control Flight Research Program

    Science.gov (United States)

    Powers, Sheryll Goecke (Compiler)

    1995-01-01

    Flight research for the F-15 HIDEC (Highly Integrated Digital Electronic Control) program was completed at NASA Dryden Flight Research Center in the fall of 1993. The flight research conducted during the last two years of the HIDEC program included two principal experiments: (1) performance seeking control (PSC), an adaptive, real-time, on-board optimization of engine, inlet, and horizontal tail position on the F-15; and (2) propulsion controlled aircraft (PCA), an augmented flight control system developed for landings as well as up-and-away flight that used only engine thrust (flight controls locked) for flight control. In September 1994, the background details and results of the PSC and PCA experiments were presented in an electronic workshop, accessible through the Dryden World Wide Web (http://www.dfrc.nasa.gov/dryden.html) and as a compact disk.

  10. The computer-based Symbol Digit Modalities Test: establishing age-expected performance in healthy controls and evaluation of pediatric MS patients.

    Science.gov (United States)

    Bigi, Sandra; Marrie, R A; Till, C; Yeh, E A; Akbar, N; Feinstein, A; Banwell, B L

    2017-04-01

    Decreased information processing speed (IPS) is frequently reported in pediatric multiple sclerosis (MS) patients. The computerized version of the Symbol Digit Modalities Test (c-SDMT) measures IPS over eight consecutive trials per session and additionally captures changes in performance within the session. Here, we establish normative c-SDMT performance and test-retest reliability in healthy children (HC) and explore differences in the overall c-SDMT-performance between HC and MS patients. This cross-sectional study included 478 HC (237 female, 49.5%) divided into five age groups (2 years each), and 27 MS patients (22 female, 81.5%) aged 8-18 years. The average time to complete the c-SDMT increased with age (|r| 0.70, 95% CI -0.74, -0.64). Test-retest reliability was high (ICC = 0.91) in HC. The total time to complete the c-SDMT did not differ between children with MS and sex- and age- matched HC (p = 0.23). However, MS patients were less likely to show faster performance across all the successive eight trials compared to HC (p = 0.0001). Healthy children demonstrate faster IPS with increasing age, as well as during successive trials of the c-SDMT. The inability of pediatric MS patients to maintain the increase in processing speed over successive trials suggests a reduced capacity for procedural learning, possibly resulting from cognitive fatigue.

  11. A low-cost, high-performance, digital signal processor-based lock-in amplifier capable of measuring multiple frequency sweeps simultaneously

    International Nuclear Information System (INIS)

    Sonnaillon, Maximiliano Osvaldo; Bonetto, Fabian Jose

    2005-01-01

    A high-performance digital lock-in amplifier implemented in a low-cost digital signal processor (DSP) board is described. This lock in is capable of measuring simultaneously multiple frequencies that change in time as frequency sweeps (chirps). The used 32-bit DSP has enough computing power to generate N=3 simultaneous reference signals and accurately measure the N=3 responses, operating as three lock ins connected in parallel to a linear system. The lock in stores the measured values in memory until they are downloaded to the a personal computer (PC). The lock in works in stand-alone mode and can be programmed and configured through the PC serial port. Downsampling and multiple filter stages were used in order to obtain a sharp roll off and a long time constant in the filters. This makes measurements possible in presence of high-noise levels. Before each measurement, the lock in performs an autocalibration that measures the frequency response of analog output and input circuitry in order to compensate for the departure from ideal operation. Improvements from previous lock-in implementations allow measuring the frequency response of a system in a short time. Furthermore, the proposed implementation can measure how the frequency response changes with time, a characteristic that is very important in our biotechnological application. The number of simultaneous components that the lock in can generate and measure can be extended, without reprogramming, by only using other DSPs of the same family that are code compatible and work at higher clock frequencies

  12. A low-cost, high-performance, digital signal processor-based lock-in amplifier capable of measuring multiple frequency sweeps simultaneously

    Energy Technology Data Exchange (ETDEWEB)

    Sonnaillon, Maximiliano Osvaldo; Bonetto, Fabian Jose [Laboratorio de Cavitacion y Biotecnologia, San Carlos de Bariloche (8400) (Argentina)

    2005-02-01

    A high-performance digital lock-in amplifier implemented in a low-cost digital signal processor (DSP) board is described. This lock in is capable of measuring simultaneously multiple frequencies that change in time as frequency sweeps (chirps). The used 32-bit DSP has enough computing power to generate N=3 simultaneous reference signals and accurately measure the N=3 responses, operating as three lock ins connected in parallel to a linear system. The lock in stores the measured values in memory until they are downloaded to the a personal computer (PC). The lock in works in stand-alone mode and can be programmed and configured through the PC serial port. Downsampling and multiple filter stages were used in order to obtain a sharp roll off and a long time constant in the filters. This makes measurements possible in presence of high-noise levels. Before each measurement, the lock in performs an autocalibration that measures the frequency response of analog output and input circuitry in order to compensate for the departure from ideal operation. Improvements from previous lock-in implementations allow measuring the frequency response of a system in a short time. Furthermore, the proposed implementation can measure how the frequency response changes with time, a characteristic that is very important in our biotechnological application. The number of simultaneous components that the lock in can generate and measure can be extended, without reprogramming, by only using other DSPs of the same family that are code compatible and work at higher clock frequencies.

  13. Digital Audiobooks

    DEFF Research Database (Denmark)

    Have, Iben; Pedersen, Birgitte Stougaard

    Audiobooks are rapidly gaining popularity with widely accessible digital downloading and streaming services. The paper is framing how the digital audiobook expands and changes the target groups for book publications and how it as an everyday activity is creating new reading experiences, places...

  14. Digital TMI

    Science.gov (United States)

    Rios, Joseph

    2012-01-01

    Presenting the current status of the Digital TMI project to visiting members of the FAA Command Center. Digital TMI is an effort to store national-level traffic management initiatives in a standards-compliant manner. Work is funded by the FAA.

  15. Digital displacements

    DEFF Research Database (Denmark)

    Pors, Anja Svejgaard

    2014-01-01

    In recent years digital reforms are being introduced in the municipal landscape of Denmark. The reforms address the interaction between citizen and local authority. The aim is, that by 2015 at least 80 per cent of all correspondence between citizens and public authority will be transmitted through...... digital interface. However, the transformation of citizen services from traditional face-to-face interaction to digital self-service gives rise to new practices; some citizens need support to be able to manage self-service through digital tools. A mixture of support and teaching, named co......-service, is a new task in public administration, where street level bureaucrats assist citizens in using the new digital solutions. The paper is based on a case study conducted primarily in a citizen service centre in Copenhagen, Denmark. Based on ethnography the paper gives an empirical account of the ongoing...

  16. Digitized mammograms

    International Nuclear Information System (INIS)

    Bruneton, J.N.; Balu-Maestro, C.; Rogopoulos, A.; Chauvel, C.; Geoffray, A.

    1988-01-01

    Two observers conducted a blind evaluation of 100 mammography files, including 47 malignant cases. Films were read both before and after image digitization at 50 μm and 100 μm with the FilmDRSII. Digitization permitted better analysis of the normal anatomic structures and moderately improved diagnostic sensitivity. Searches for microcalcifications before and after digitization at 100 μm and 50 μm showed better analysis of anatomic structures after digitization (especially for solitary microcalcifications). The diagnostic benefit, with discovery of clustered microcalcifications, was more limited (one case at 100 μm, nine cases at 50 μm). Recognition of microcalcifications was clearly improved in dense breasts, which can benefit from reinterpretation after digitization at 50 μm rather 100μm

  17. Exploring Performance Determinants of China’s Cable Operators and OTT Service Providers in the Era of Digital Convergence—From the Perspective of an Industry Platform

    Directory of Open Access Journals (Sweden)

    Xing Wan

    2017-12-01

    Full Text Available This paper investigates key determinants of business performance in China’s video industry in the era of digital convergence. Specifically, we analyze China’s OTT (over-the-top service providers and cable operators based on the perspective of an industry platform, which acts as the core module of a business ecosystem and is capable of facilitating and coordinating interdependence among different agents. Panel data models are established to empirically explore what factors impact the performance of these two types of players. The findings demonstrate that both platform use and the size of an installed base are crucial for the determinants of the performance of OTT service providers and cable operators. An online video platform can also benefit from an increasing proportion of mobile viewers by implementing a multi-screen strategy. Further, an OTT service provider can profit from the interaction between its installed base and UGC (user-generated content, while cable operators can take advantage of positive feedback between their demand side and supply side.

  18. Digital pulse shape discrimination

    International Nuclear Information System (INIS)

    Miller, L. F.; Preston, J.; Pozzi, S.; Flaska, M.; Neal, J.

    2007-01-01

    Pulse-shape discrimination (PSD) has been utilised for about 40 years as a method to obtain estimates for dose in mixed neutron and photon fields. Digitizers that operate close to GHz are currently available at a reasonable cost, and they can be used to directly sample signals from photomultiplier tubes. This permits one to perform digital PSD rather than the traditional, and well-established, analogous techniques. One issue that complicates PSD for neutrons in mixed fields is that the light output characteristics of typical scintillators available for PSD, such as BC501A, vary as a function of energy deposited in the detector. This behaviour is more easily accommodated with digital processing of signals than with analogous signal processing. Results illustrate the effectiveness of digital PSD. (authors)

  19. Forensic examination of ink by high-performance thin layer chromatography--the United States Secret Service Digital Ink Library.

    Science.gov (United States)

    Neumann, Cedric; Ramotowski, Robert; Genessay, Thibault

    2011-05-13

    Forensic examinations of ink have been performed since the beginning of the 20th century. Since the 1960s, the International Ink Library, maintained by the United States Secret Service, has supported those analyses. Until 2009, the search and identification of inks were essentially performed manually. This paper describes the results of a project designed to improve ink samples' analytical and search processes. The project focused on the development of improved standardization procedures to ensure the best possible reproducibility between analyses run on different HPTLC plates. The successful implementation of this new calibration method enabled the development of mathematical algorithms and of a software package to complement the existing ink library. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. The Influence of E-learning Use to Student Cognitive Performance and Motivation in Digital Simulation Course

    Directory of Open Access Journals (Sweden)

    Tigowati Tigowati

    2017-12-01

    Full Text Available Currently the technology is growing and sophisticated. Technological advances have also entered the world of education. One of them their is  online learning. Examples of learning that utilizes technology that is using Schoology and Edmodo. By using Schoology and Edmodo is expected to increase student motivation and learning outcomes. This study investigates whether the use of different learning management would affect (1 the student’s cognitive achievement (2 student’s motivation (3 the level motivation. This research method using mixed methods. The data collection technique using the test method to determine the cognitive performance. Questionnaires and interviews to find the motivation. The analysis of quantitative data using normality test, homogeneity test, tests of balance and hypothesis testing using independent t test, while the analysis of qualitative data using interactive models. Based on the results of the study (1 there are differences in the cognitive performance between classes that use e-learning based Schoology and e-learning based Edmodo. The cognitive performance classes that use Schoology better than the class that uses Edmodo, because schoology easiness to acces, the students has a target value, better understand the lesson and more active in study this may have an effect on cognitive performance.(2 there is a difference in motivation between classes that use e-learning based Schoology and e-learning based Edmodo. Motivation class with Schoology based e-learning is better than classes with e-learning based Edmodo, because schoology can interested in simulation course, more passion, make happy, easier to learn anywhere and more motivated to learn. (3 the level of motivation of students using e-learning based Schoology and Edmodo included in the medium category

  1. Digital Ethics/Going Digital.

    Science.gov (United States)

    Wilson, Bradley

    1996-01-01

    Finds that the recent National Press Photographers Association code of ethics can serve as a model for any photography staff. Discusses how digital imaging is becoming commonplace in classrooms, due to decreasing costs and easier software. Explains digital terminology. Concludes that time saved in the darkroom and at the printer is now spent on…

  2. Elastogram quality assessment score in vibration-controlled transient elastography: Diagnostic performance compared to digital morphometric analysis of liver biopsy in chronic hepatitis C.

    Science.gov (United States)

    Mendes, L C; Ferreira, P A; Miotto, N; Zanaga, L; Gonçales, E S L; Pedro, M N; Lazarini, M S; Júnior, F L G; Stucchi, R S B; Vigani, A G

    2018-04-01

    Vibration-controlled transient elastography (VCTE) is widely used for noninvasive fibrosis staging in chronic hepatitis C. However, internal validation is based solely on variability and success rate and lacks reproducible quality indicators. We analysed the graphic representation of shear wave propagation in comparison with morphometric results of liver biopsy, eliminating observer variability bias. Individual elastograms were classified according to two morphologic criteria: extension of wave propagation (length of the graphic representation) and shear wave dispersal (level of parallelism displayed in the elastogram). Then, a score based on these criteria stratified the elastogram in classes I through III (highest to lowest technical quality). Liver stiffness results of each measurement were compared with collagen contents in liver biopsy by morphometric analysis. A total of 3243 elastograms were studied (316 patients). Digital morphometry in liver biopsy showed significant fibrosis in 66% of samples and advanced fibrosis in 31%. Elastogram quality analysis resulted in 1438 class I measurements (44%), 1070 class II (34%) and 735 class III. Area under the receiver operating curve (AUROC) for severe fibrosis according to class (I, II and III) was 0.941, 0.887 and 0.766, respectively. For advanced fibrosis, AUROCs were 0.977, 0.883 and 0.781, respectively. Spearman's correlation testing for all classes and levels of fibrosis demonstrated significant independent association (r 2  = -.95, P digital morphometric imaging analysis. We concluded that VCTE performance is significantly influenced by quality assessment of individual measurements. Considering these criteria in clinical practice may improve accuracy. © 2017 John Wiley & Sons Ltd.

  3. Digital radiography

    International Nuclear Information System (INIS)

    Coulomb, M.; Dal Soglio, S.; Pittet-Barbier, L.; Ranchoup, Y.; Thony, F.; Ferretti, G.; Robert, F.

    1992-01-01

    Digital projection radiography may replace conventional radiography some day, provided it can meet several requirements: equal or better diagnostic effectiveness of the screen-film systems; reasonable image cost; real improvement in the productivity of the Departments of Imaging. All digital radiographic systems include an X-ray source, an image acquisition and formatting sub-system, a display and manipulation sub-system, and archiving subsystem and a laser editing system, preferably shared by other sources of digital images. Three digitization processes are available: digitization of the radiographic film, digital fluorography and phospholuminescent detectors with memory. The advantages of digital fluoroscopy are appealing: real-time image acquisition, suppression of cassettes; but its disadvantages are far from negligible: it cannot be applied to bedside radiography, the field of examination is limited, and the wide-field spatial resolution is poor. Phospholuminescent detectors with memory have great advantages: they can be used for bedside radiographs and on all the common radiographic systems; spatial resolution is satisfactory; its current disadvantages are considerable. These two systems, have common properties making up the entire philosophy of digital radiology and specific features that must guide our choice according to the application. Digital fluorography is best applied in pediatric radiology. However, evaluation works have showed that it was applicable with sufficient quality to many indications of general radiology in which a fluoroscopic control and fast acquisition of the images are essential; the time gained on the examination may be considerable, as well as the savings on film. Detectors with memory are required for bedside radiographs, in osteoarticular and thoracic radiology, in all cases of traumatic emergency and in the resuscitation and intensive care departments

  4. Architectural Optimization of Digital Libraries

    Science.gov (United States)

    Biser, Aileen O.

    1998-01-01

    This work investigates performance and scaling issues relevant to large scale distributed digital libraries. Presently, performance and scaling studies focus on specific implementations of production or prototype digital libraries. Although useful information is gained to aid these designers and other researchers with insights to performance and scaling issues, the broader issues relevant to very large scale distributed libraries are not addressed. Specifically, no current studies look at the extreme or worst case possibilities in digital library implementations. A survey of digital library research issues is presented. Scaling and performance issues are mentioned frequently in the digital library literature but are generally not the focus of much of the current research. In this thesis a model for a Generic Distributed Digital Library (GDDL) and nine cases of typical user activities are defined. This model is used to facilitate some basic analysis of scaling issues. Specifically, the calculation of Internet traffic generated for different configurations of the study parameters and an estimate of the future bandwidth needed for a large scale distributed digital library implementation. This analysis demonstrates the potential impact a future distributed digital library implementation would have on the Internet traffic load and raises questions concerning the architecture decisions being made for future distributed digital library designs.

  5. Becoming digital

    DEFF Research Database (Denmark)

    Pors, Anja Svejgaard

    2015-01-01

    . An ethnographic account of how digital reforms are implemented in practice shows how street-level bureaucrat’s classic tasks such as specialized casework are being reconfigured into educational tasks that promote the idea of “becoming digital”. In the paper, the author argues that the work of “becoming digital....... Originality/value: The study contributes to ethnographic research in public administration by combining two separate subfields, e-government and street-level bureaucracy, to discern recent transformations in public service delivery. In the digital era, tasks, control and equality are distributed in ways...

  6. Digital Humanities

    DEFF Research Database (Denmark)

    Brügger, Niels

    2016-01-01

    , and preserving material to study, as an object of study in its own right, as an analytical tool, or for collaborating, and for disseminating results. The term "digital humanities" was coined around 2001, and gained currency within academia in the following years. However, computers had been used within......Digital humanities is an umbrella term for theories, methodologies, and practices related to humanities scholarship that use the digital computer as an integrated and essential part of its research and teaching activities. The computer can be used for establishing, finding, collecting...

  7. Digital Snaps

    DEFF Research Database (Denmark)

    Sandbye, Mette; Larsen, Jonas

    . Distance as the New Punctum / Mikko Villi -- pt. II. FAMILY ALBUMS IN TRANSITION -- ch. 4. How Digital Technologies Do Family Snaps, Only Better / Gillian Rose -- ch. 5. Friendship Photography: Memory, Mobility and Social Networking / Joanne Garde-Hansen -- ch. 6. Play, Process and Materiality in Japanese...... -- ch. 9. Retouch Yourself: The Pleasures and Politics of Digital Cosmetic Surgery / Tanya Sheehan -- ch. 10. Virtual Selves: Art and Digital Autobiography / Louise Wolthers -- ch. 11. Mobile-Media Photography: New Modes of Engagement / Michael Shanks and Connie Svabo....

  8. Digital electronics

    CERN Document Server

    Morris, John

    2013-01-01

    An essential companion to John C Morris's 'Analogue Electronics', this clear and accessible text is designed for electronics students, teachers and enthusiasts who already have a basic understanding of electronics, and who wish to develop their knowledge of digital techniques and applications. Employing a discovery-based approach, the author covers fundamental theory before going on to develop an appreciation of logic networks, integrated circuit applications and analogue-digital conversion. A section on digital fault finding and useful ic data sheets completes th

  9. Digital Leadership

    DEFF Research Database (Denmark)

    Zupancic, Tadeja; Verbeke, Johan; Achten, Henri

    2016-01-01

    Leadership is an important quality in organisations. Leadership is needed to introduce change and innovation. In our opinion, in architectural and design practices, the role of leadership has not yet been sufficiently studied, especially when it comes to the role of digital tools and media....... With this paper we intend to initiate a discussion in the eCAADe community to reflect and develop ideas in order to develop digital leadership skills amongst the membership. This paper introduces some important aspects, which may be valuable to look into when developing digital leadership skills....

  10. Digital radiography

    International Nuclear Information System (INIS)

    Zani, M.L.

    2002-01-01

    X-ray radiography is a very common technique used to check the homogeneity of a material or the inside of a mechanical part. Generally the radiation that goes through the material to check, produced an image on a sensitized film. This method requires time because the film needs to be developed, digital radiography has no longer this inconvenient. In digital radiography the film is replaced by digital data and can be processed as any computer file. This new technique is promising but its main inconvenient is that today its resolution is not so good as that of film radiography. (A.C.)

  11. Digital radiography

    International Nuclear Information System (INIS)

    Kusano, Shoichi

    1993-01-01

    Firstly, from an historic point of view, fundamental concepts on digital imaging were reviewed to provide a foundation for discussion of digital radiography. Secondly, this review summarized the results of ongoing research in computed radiography that replaces the conventional film-screen system with a photo-stimulable phosphor plate; and thirdly, image quality, radiation protection, and image processing techniques were discussed with emphasis on picture archiving and communication system environment as our final goal. Finally, future expansion of digital radiography was described based on the present utilization of computed tomography at the National Defense Medical College Hospital. (author) 60 refs

  12. Development and Comparative Study of Effects of Training Algorithms on Performance of Artificial Neural Network Based Analog and Digital Automatic Modulation Recognition

    Directory of Open Access Journals (Sweden)

    Jide Julius Popoola

    2015-11-01

    Full Text Available This paper proposes two new classifiers that automatically recognise twelve combined analog and digital modulated signals without any a priori knowledge of the modulation schemes and the modulation parameters. The classifiers are developed using pattern recognition approach. Feature keys extracted from the instantaneous amplitude, instantaneous phase and the spectrum symmetry of the simulated signals are used as inputs to the artificial neural network employed in developing the classifiers. The two developed classifiers are trained using scaled conjugate gradient (SCG and conjugate gradient (CONJGRAD training algorithms. Sample results of the two classifiers show good success recognition performance with an average overall recognition rate above 99.50% at signal-to-noise ratio (SNR value from 0 dB and above with the two training algorithms employed and an average overall recognition rate slightly above 99.00% and 96.40% respectively at - 5 dB SNR value for SCG and CONJGRAD training algorithms. The comparative performance evaluation of the two developed classifiers using the two training algorithms shows that the two training algorithms have different effects on both the response rate and efficiency of the two developed artificial neural networks classifiers. In addition, the result of the performance evaluation carried out on the overall success recognition rates between the two developed classifiers in this study using pattern recognition approach with the two training algorithms and one reported classifier in surveyed literature using decision-theoretic approach shows that the classifiers developed in this study perform favourably with regard to accuracy and performance probability as compared to classifier presented in previous study.

  13. Video gaming and gender differences in digital and printed reading performance among 15-year-olds students in 26 countries.

    Science.gov (United States)

    Borgonovi, Francesca

    2016-04-01

    Video games are a favorite leisure-time activity among teenagers worldwide. This study examines cross-national gender differences in reading achievement and video gaming and whether video gaming explains gender differences in reading achievement and differences in performance between paper-based and computer-based reading. We use data from a representative sample of 145,953 students from 26 countries who sat the PISA 2012 assessments and provided self-reports on use of video games. Although boys tend to have poorer results in both the computer-based and the paper-based reading assessments, boys' under achievement is smaller when the assessment is delivered on computer than when it is delivered on paper. Boys underperformance compared to girls in the two reading assessments is particularly pronounced among low-achieving students. Among both boys and girls moderate use of single-player games is associated with a performance advantage. However, frequent engagement with collaborative online games is generally associated with a steep reduction in achievement, particularly in the paper-based test and particularly among low-achieving students. Excessive gaming may hinder academic achievement, but moderate gaming can promote positive student outcomes. In many countries video gaming explains the difference in the gender gap in reading between the paper-based and the computer-based assessments. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  14. PET performance and MRI compatibility evaluation of a digital, ToF-capable PET/MRI insert equipped with clinical scintillators

    International Nuclear Information System (INIS)

    Schug, David; Wehner, Jakob; Dueppenbecker, Peter Michael; Weissler, Bjoern; Goldschmidt, Benjamin; Schulz, Volkmar; Gebhardt, Pierre; Salomon, Andre; Kiessling, Fabian

    2015-01-01

    We evaluate the MR compatibility of the Hyperion-II D positron emission tomography (PET) insert, which allows simultaneous operation in a clinical magnetic resonance imaging (MRI) scanner. In contrast to previous investigations, this work aims at the evaluation of a clinical crystal configuration. An imaging-capable demonstrator with an axial field-of-view of 32 mm and a crystal-to-crystal spacing of 217.6 mm was equipped with LYSO scintillators with a pitch of 4 mm which were read out in a one-to-one coupling scheme by sensor tiles composed of digital silicon photomultipliers from Philips Digital Photon Counting (DPC 3200-22). The PET performance degradation (energy resolution and coincidence resolution time (CRT)) was evaluated during simultaneous operation of the MRI scanner. We used clinically motivated imaging sequences as well as synthetic gradient stress test sequences. Without activity of the MRI scanner, we measured for trigger scheme 1 (first photon trigger) an energy resolution of 11.4% and a CRT of 213 ps for a narrow energy (NE) window using five 22 Na point-like sources. When applying the synthetic gradient sequences, we found worst-case relative degradations of the energy resolution by 5.1% and of the CRT by 33.9%. After identifying the origin of the degradations and implementing a fix to the read-out hardware, the same evaluation revealed no degradation of the PET performance anymore even when the most demanding gradient stress tests were applied. The PET performance of the insert was initially evaluated using the point sources, a high-activity phantom and hot-rod phantoms in order to assess the spatial resolution. Trigger schemes 2–4 delivered an energy resolution of 11.4% as well and CRTs of 279 ps, 333 ps and 557 ps for the NE window, respectively. An isocenter sensitivity of 0.41% using the NE window and 0.71% with a wide energy window was measured. Using a hot-rod phantom, a spatial resolution in the order of 2 mm was demonstrated and

  15. PET performance and MRI compatibility evaluation of a digital, ToF-capable PET/MRI insert equipped with clinical scintillators

    Science.gov (United States)

    Schug, David; Wehner, Jakob; Dueppenbecker, Peter Michael; Weissler, Bjoern; Gebhardt, Pierre; Goldschmidt, Benjamin; Salomon, Andre; Kiessling, Fabian; Schulz, Volkmar

    2015-09-01

    We evaluate the MR compatibility of the Hyperion-IID positron emission tomography (PET) insert, which allows simultaneous operation in a clinical magnetic resonance imaging (MRI) scanner. In contrast to previous investigations, this work aims at the evaluation of a clinical crystal configuration. An imaging-capable demonstrator with an axial field-of-view of 32 mm and a crystal-to-crystal spacing of 217.6 mm was equipped with LYSO scintillators with a pitch of 4 mm which were read out in a one-to-one coupling scheme by sensor tiles composed of digital silicon photomultipliers from Philips Digital Photon Counting (DPC 3200-22). The PET performance degradation (energy resolution and coincidence resolution time (CRT)) was evaluated during simultaneous operation of the MRI scanner. We used clinically motivated imaging sequences as well as synthetic gradient stress test sequences. Without activity of the MRI scanner, we measured for trigger scheme 1 (first photon trigger) an energy resolution of 11.4% and a CRT of 213 ps for a narrow energy (NE) window using five 22Na point-like sources. When applying the synthetic gradient sequences, we found worst-case relative degradations of the energy resolution by 5.1% and of the CRT by 33.9%. After identifying the origin of the degradations and implementing a fix to the read-out hardware, the same evaluation revealed no degradation of the PET performance anymore even when the most demanding gradient stress tests were applied. The PET performance of the insert was initially evaluated using the point sources, a high-activity phantom and hot-rod phantoms in order to assess the spatial resolution. Trigger schemes 2-4 delivered an energy resolution of 11.4% as well and CRTs of 279 ps, 333 ps and 557 ps for the NE window, respectively. An isocenter sensitivity of 0.41% using the NE window and 0.71% with a wide energy window was measured. Using a hot-rod phantom, a spatial resolution in the order of 2 mm was demonstrated and the

  16. Dataset on the learning performance of ECDL digital skills of undergraduate students for comparing educational gaming, gamification and social networking

    Directory of Open Access Journals (Sweden)

    Luis de-Marcos

    2017-04-01

    Full Text Available This paper reports data about the learning performance of students using four different motivational tools: an educational game, a gamified plugin, a social networking website and a gamified social networking website. It also reports a control group. The data pertain to 379 students of an undergraduate course that covers basic Information and Communication Technology (ICT skills in Spain. Data corresponds to different learning modules of the European Computer Driving License (ECDL initiative. The data include variables of four pre-test scores, four post-test scores and a final examination. It was gathered using a quasi-experimental research design during 2014. Data reported here refers to the research paper in (de-Marcos et al., 2016 [1].

  17. Dataset on the learning performance of ECDL digital skills of undergraduate students for comparing educational gaming, gamification and social networking.

    Science.gov (United States)

    de-Marcos, Luis; García-López, Eva; García-Cabot, Antonio

    2017-04-01

    This paper reports data about the learning performance of students using four different motivational tools: an educational game, a gamified plugin, a social networking website and a gamified social networking website. It also reports a control group. The data pertain to 379 students of an undergraduate course that covers basic Information and Communication Technology (ICT) skills in Spain. Data corresponds to different learning modules of the European Computer Driving License (ECDL) initiative. The data include variables of four pre-test scores, four post-test scores and a final examination. It was gathered using a quasi-experimental research design during 2014. Data reported here refers to the research paper in (de-Marcos et al., 2016) [1].

  18. SENTINEL-2 GLOBAL REFERENCE IMAGE VALIDATION AND APPLICATION TO MULTITEMPORAL PERFORMANCES AND HIGH LATITUDE DIGITAL SURFACE MODEL

    Directory of Open Access Journals (Sweden)

    A. Gaudel

    2017-05-01

    Full Text Available In the frame of the Copernicus program of the European Commission, Sentinel-2 is a constellation of 2 satellites with a revisit time of 5 days in order to have temporal images stacks and a global coverage over terrestrial surfaces. Satellite 2A was launched in June 2015, and satellite 2B will be launched in March 2017. In cooperation with the European Space Agency (ESA, the French space agency (CNES is in charge of the image quality of the project, and so ensures the CAL/VAL commissioning phase during the months following the launch. This cooperation is also extended to routine phase as CNES supports European Space Research Institute (ESRIN and the Sentinel-2 Mission performance Centre (MPC for validation in geometric and radiometric image quality aspects, and in Sentinel-2 GRI geolocation performance assessment whose results will be presented in this paper. The GRI is a set of S2A images at 10m resolution covering the whole world with a good and consistent geolocation. This ground reference enables accurate multi-temporal registration of refined Sentinel-2 products. While not primarily intended for the generation of DSM, Sentinel-2 swaths overlap between orbits would also allow for the generation of a complete DSM of land and ices over 60° of northern latitudes (expected accuracy: few S2 pixels in altimetry. This DSM would benefit from the very frequent revisit times of Sentinel-2, to monitor ice or snow level in area of frequent changes, or to increase measurement accuracy in areas of little changes.

  19. SENTINEL-2 Global Reference Image Validation and Application to Multitemporal Performances and High Latitude Digital Surface Model

    Science.gov (United States)

    Gaudel, A.; Languille, F.; Delvit, J. M.; Michel, J.; Cournet, M.; Poulain, V.; Youssefi, D.

    2017-05-01

    In the frame of the Copernicus program of the European Commission, Sentinel-2 is a constellation of 2 satellites with a revisit time of 5 days in order to have temporal images stacks and a global coverage over terrestrial surfaces. Satellite 2A was launched in June 2015, and satellite 2B will be launched in March 2017. In cooperation with the European Space Agency (ESA), the French space agency (CNES) is in charge of the image quality of the project, and so ensures the CAL/VAL commissioning phase during the months following the launch. This cooperation is also extended to routine phase as CNES supports European Space Research Institute (ESRIN) and the Sentinel-2 Mission performance Centre (MPC) for validation in geometric and radiometric image quality aspects, and in Sentinel-2 GRI geolocation performance assessment whose results will be presented in this paper. The GRI is a set of S2A images at 10m resolution covering the whole world with a good and consistent geolocation. This ground reference enables accurate multi-temporal registration of refined Sentinel-2 products. While not primarily intended for the generation of DSM, Sentinel-2 swaths overlap between orbits would also allow for the generation of a complete DSM of land and ices over 60° of northern latitudes (expected accuracy: few S2 pixels in altimetry). This DSM would benefit from the very frequent revisit times of Sentinel-2, to monitor ice or snow level in area of frequent changes, or to increase measurement accuracy in areas of little changes.

  20. Digital fabrication

    CERN Document Server

    2012-01-01

    The Winter 2012 (vol. 14 no. 3) issue of the Nexus Network Journal features seven original papers dedicated to the theme “Digital Fabrication”. Digital fabrication is changing architecture in fundamental ways in every phase, from concept to artifact. Projects growing out of research in digital fabrication are dependent on software that is entirely surface-oriented in its underlying mathematics. Decisions made during design, prototyping, fabrication and assembly rely on codes, scripts, parameters, operating systems and software, creating the need for teams with multidisciplinary expertise and different skills, from IT to architecture, design, material engineering, and mathematics, among others The papers grew out of a Lisbon symposium hosted by the ISCTE-Instituto Universitario de Lisboa entitled “Digital Fabrication – A State of the Art”. The issue is completed with four other research papers which address different mathematical instruments applied to architecture, including geometric tracing system...

  1. Digital Relationships

    DEFF Research Database (Denmark)

    Ledborg Hansen, Richard

    -­rich information and highly interesting communication are sky-­high and rising. With a continuous increase in digitized communication follows a decrease in face-­to-­face encounters and our ability to engage in inter-­personal relationships are suffering for it (Davis, 2013). The behavior described in this paper......-­‐Jones, 2011) for increases in effectiveness and efficiency we indiscriminately embrace digital communication and digitized information dissemination with enthusiasm – at the risk of ignoring the potentially dark side of technology. However, technology also holds a promise for better understanding precisely...... for the same reasons – that the growing amount of digitized communication “out there” represents data waiting to be sifted, analyzed and decoded. In this paper “Facebook behavior” refers to a particular behavior characterized by presenting your self and representations of selected self in the hope of getting...

  2. Digital Discretion

    DEFF Research Database (Denmark)

    Busch, Peter Andre; Zinner Henriksen, Helle

    2018-01-01

    discretion is suggested to reduce this footprint by influencing or replacing their discretionary practices using ICT. What is less researched is whether digital discretion can cause changes in public policy outcomes, and under what conditions such changes can occur. Using the concept of public service values......This study reviews 44 peer-reviewed articles on digital discretion published in the period from 1998 to January 2017. Street-level bureaucrats have traditionally had a wide ability to exercise discretion stirring debate since they can add their personal footprint on public policies. Digital......, we suggest that digital discretion can strengthen ethical and democratic values but weaken professional and relational values. Furthermore, we conclude that contextual factors such as considerations made by policy makers on the macro-level and the degree of professionalization of street...

  3. Digital setup for Doppler broadening spectroscopy

    International Nuclear Information System (INIS)

    Cizek, J; Vlcek, M; Prochazka, I

    2011-01-01

    New digital spectrometer for measurement of the Doppler shift of annihilation photons was developed and tested in this work. Digital spectrometer uses a fast 12-bit digitizer for direct sampling of signals from HPGe detectors. Analysis of sampled waveforms is performed off-line in software. Performance of the new digital setup was compared with its traditional analogue counterpart. Superior energy resolution was achieved in the digital setup. Moreover, the digital setup allows for a better control of the shape of detector signals. This enables to eliminate undesired signals damaged by pile-up effects or by ballistic deficit.

  4. Computer-aided detection system performance on current and previous digital mammograms in patients with contralateral metachronous breast cancer

    International Nuclear Information System (INIS)

    Kim, Seung Ja; Moon, Woo Kyung; Cho, Nariya; Chang, Jung Min

    2012-01-01

    Background: The computer-aided detection (CAD) system is widely used for screening mammography. The performance of the CAD system for contralateral breast cancer has not been reported for women with a history of breast cancer. Purpose: To retrospectively evaluate the performance of a CAD system on current and previous mammograms in patients with contralateral metachronous breast cancer. Material and Methods: During a 3-year period, 4945 postoperative patients had follow-up examinations, from whom we selected 55 women with contralateral breast cancers. Among them, 38 had visible malignant signs on the current mammograms. We analyzed the sensitivity and false-positive marks of the system on the current and previous mammograms according to lesion type and breast density. Results: The total visible lesion components on the current mammograms included 27 masses and 14 calcifications in 38 patients. The case-based sensitivity for all lesion types was 63.2% (24/38) with false-positive marks of 0.71 per patient. The lesion-based sensitivity for masses and calcifications was 59.3% (16/27) and 71.4% (10/14), respectively. The lesion-based sensitivity for masses in fatty and dense breasts was 68.8% (11/16) and 45.5% (5/11), respectively. The lesion-based sensitivity for calcifications in fatty and dense breasts was 100.0% (3/3) and 63.6% (7/11), respectively. The total visible lesion components on the previous mammograms included 13 masses and three calcifications in 16 patients, and the sensitivity for all lesion types was 31.3% (5/16) with false-positive marks of 0.81 per patient. On these mammograms, the sensitivity for masses and calcifications was 30.8% (4/13) and 33.3% (1/3), respectively. The sensitivity in fatty and dense breasts was 28.6% (2/7) and 33.3% (3/9), respectively. Conclusion: In the women with a history of breast cancer, the sensitivity of the CAD system in visible contralateral breast cancer was lower than in most previous reports using the same CAD

  5. Digital fluxgate magnetometer: design notes

    International Nuclear Information System (INIS)

    Belyayev, Serhiy; Ivchenko, Nickolay

    2015-01-01

    We presented an approach to understanding the performance of a fully digital fluxgate magnetometer. All elements of the design are important for the performance of the instrument, and the presence of the digital feed-back loop introduces certain peculiarities affecting the noise and dynamic performance of the instrument. Ultimately, the quantisation noise of the digital to analogue converter is found to dominate the noise of the current design, although noise shaping alleviates its effect to some extent. An example of magnetometer measurements on board a sounding rocket is presented, and ways to further improve the performance of the instrument are discussed. (paper)

  6. Digital fluxgate magnetometer: design notes

    Science.gov (United States)

    Belyayev, Serhiy; Ivchenko, Nickolay

    2015-12-01

    We presented an approach to understanding the performance of a fully digital fluxgate magnetometer. All elements of the design are important for the performance of the instrument, and the presence of the digital feed-back loop introduces certain peculiarities affecting the noise and dynamic performance of the instrument. Ultimately, the quantisation noise of the digital to analogue converter is found to dominate the noise of the current design, although noise shaping alleviates its effect to some extent. An example of magnetometer measurements on board a sounding rocket is presented, and ways to further improve the performance of the instrument are discussed.

  7. Digital radiology and digitally formatted image management systems

    International Nuclear Information System (INIS)

    Cox, G.G.; Dwyer, S.J. III; Templeton, A.W.

    1987-01-01

    The number of diagnostic examinations performed with digitally formatted imaging equipment is increasing. Digital general-purpose and fluoroscopic radiology systems are being clinically evaluated. Digitizing conventional x-ray films, such as mammograms, frequently improves the diagnostic quality of the images. The digitizing process with laser has also afforded the opportunity to document required spatial resolution for digital imaging and network systems. The use of digitally formatted image instrumentation imposes new requirements on the acquisition, display and manipulation, transmission, hard copy image recording, and archiving of diagnostic data. Networking of digitally formatted image data offers many advantages for managing digital information. This paper identifies and describes digital radiographic systems. Parameters required for designing and implementing a digital image management system are outlined. Spatial and contrast resolution requirements are identified. The key parameters include the amount of image data generated each working day, the retrieval rate of the generated data, the display hardware and software needed for interactive diagnosis display stations, the requirements for analog hard copy generation, and on-line and long-term archiving requirements. These image management systems are often called PACS (Picture Archiving and Communication Systems)

  8. Digital Collections, Digital Libraries & the Digitization of Cultural Heritage Information.

    Science.gov (United States)

    Lynch, Clifford

    2002-01-01

    Discusses digital collections and digital libraries. Topics include broadband availability; digital rights protection; content, both non-profit and commercial; digitization of cultural content; sustainability; metadata harvesting protocol; infrastructure; authorship; linking multiple resources; data mining; digitization of reference works;…

  9. Digital Actuator Technology

    Energy Technology Data Exchange (ETDEWEB)

    Ken Thomas; Ted Quinn; Jerry Mauck; Richard Bockhorst

    2014-09-01

    There are significant developments underway in new types of actuators for power plant active components. Many of these make use of digital technology to provide a wide array of benefits in performance of the actuators and in reduced burden to maintain them. These new product offerings have gained considerable acceptance in use in process plants. In addition, they have been used in conventional power generation very successfully. This technology has been proven to deliver the benefits promised and substantiate the claims of improved performance. The nuclear industry has been reluctant to incorporate digital actuator technology into nuclear plant designs due to concerns due to a number of concerns. These could be summarized as cost, regulatory uncertainty, and a certain comfort factor with legacy analog technology. The replacement opportunity for these types of components represents a decision point for whether to invest in more modern technology that would provide superior operational and maintenance benefits. Yet, the application of digital technology has been problematic for the nuclear industry, due to qualification and regulatory issues. With some notable exceptions, the result has been a continuing reluctance to undertake the risks and uncertainties of implementing digital actuator technology when replacement opportunities present themselves. Rather, utilities would typically prefer to accept the performance limitations of the legacy analog actuator technologies to avoid impacts to project costs and schedules. The purpose of this report is to demonstrate that the benefits of digital actuator technology can be significant in terms of plant performance and that it is worthwhile to address the barriers currently holding back the widespread development and use of this technology. It addresses two important objectives in pursuit of the beneficial use of digital actuator technology for nuclear power plants: 1. To demonstrate the benefits of digital actuator

  10. digital natives and digital immigrants

    OpenAIRE

    Cardina, Bruno; Francisco, Jerónimo; Reis, Pedro; trad. Silva, Fátima

    2011-01-01

    This article focuses on the generational gaps in school learning. Initially, we have tried to provide the framework in relation to the term digital native in order to understand the key aspects of the generation born after the advent and the global use of the Internet. They were found to be “multitasking” people, linked to technology and connectivity, as opposed to digital immigrants, born in an earlier period and seeking to adapt to the technological world. We also present some r...

  11. Fast digitization and digital receiver technology

    International Nuclear Information System (INIS)

    Kimball, Ralph C.

    2002-01-01

    The potentially lucrative wireless market has led to technological advances in mixed signal devices such as high speed, high resolution A/D and D/A converters. This same market has also driven the development of high performance multi-channel digital receiver and digital transmitter ICs. Similarly, advances in semiconductor processes, coupled with the need for reduced time-to-market, has led to the development of large, enhanced performance, in-circuit programmable logic devices. A review of the key characteristics of these mixed-signal, signal processing and programmable logic devices is presented. The application of these devices and technologies to the instrumentation of Accelerators and Storage Rings is discussed and presented by way of examples. Issues relating to the requirements associated with real-time processing, I/O throughput, reconfigurability, reliability, maintainability and packaging requirements are also addressed

  12. 2017 Guralp Affinity Digitizer Evaluation.

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Bion J.

    2018-03-01

    Sandia National Laboratories has tested and evaluated two Guralp Affinity digitizers. The Affinity digitizers are intended to record sensor output for seismic and infrasound monitoring applications. The purpose of this digitizer evaluation is to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self- noise, dynamic range, system noise, response, passband, and timing. The Affinity digitizers are being evaluated for potential use in the International Monitoring System (IMS) of the Comprehensive Nuclear Test-Ban-Treaty Organization (CTBTO).

  13. Digital evidence

    Directory of Open Access Journals (Sweden)

    Lukić Tatjana

    2012-01-01

    Full Text Available Although computer makes human activities faster and easier, innovating and creating new forms of work and other kinds of activities, it also influenced the criminal activity. The development of information technology directly affects the development of computer forensics without which, it can not even imagine the discovering and proving the computer offences and apprehending the perpetrator. Information technology and computer forensic allows us to detect and prove the crimes committed by computer and capture the perpetrators. Computer forensics is a type of forensics which can be defined as a process of collecting, preserving, analyzing and presenting digital evidence in court proceedings. Bearing in mind, that combat against crime, in which computers appear as an asset or object of the offense, requires knowledge of digital evidence as well as specific rules and procedures, the author in this article specifically addresses the issues of digital evidence, forensic (computer investigation, specific rules and procedures for detecting, fixing and collecting digital evidence and use of this type of evidence in criminal proceedings. The author also delas with international standards regarding digital evidence and cyber-space investigation.

  14. Digital watermark

    Directory of Open Access Journals (Sweden)

    Jasna Maver

    2000-01-01

    Full Text Available The huge amount of multimedia contents available on the World-Wide-Web is beginning to raise the question of their protection. Digital watermarking is a technique which can serve various purposes, including intellectual property protection, authentication and integrity verification, as well as visible or invisible content labelling of multimedia content. Due to the diversity of digital watermarking applicability, there are many different techniques, which can be categorised according to different criteria. A digital watermark can be categorised as visible or invisible and as robust or fragile. In contrast to the visible watermark where a visible pattern or image is embedded into the original image, the invisible watermark does not change the visual appearance of the image. The existence of such a watermark can be determined only through a watermark ex¬traction or detection algorithm. The robust watermark is used for copyright protection, while the fragile watermark is designed for authentication and integrity verification of multimedia content. A watermark must be detectable or extractable to be useful. In some watermarking schemes, a watermark can be extracted in its exact form, in other cases, we can detect only whether a specific given watermarking signal is present in an image. Digital libraries, through which cultural institutions will make multimedia contents available, should support a wide range of service models for intellectual property protection, where digital watermarking may play an important role.

  15. Performance of Droplet Digital PCR in Non-Invasive Fetal RHD Genotyping - Comparison with a Routine Real-Time PCR Based Approach.

    Directory of Open Access Journals (Sweden)

    Iveta Svobodová

    Full Text Available Detection and characterization of circulating cell-free fetal DNA (cffDNA from maternal circulation requires an extremely sensitive and precise method due to very low cffDNA concentration. In our study, droplet digital PCR (ddPCR was implemented for fetal RHD genotyping from maternal plasma to compare this new quantification alternative with real-time PCR (qPCR as a golden standard for quantitative analysis of cffDNA. In the first stage of study, a DNA quantification standard was used. Clinical samples, including 10 non-pregnant and 35 pregnant women, were analyzed as a next step. Both methods' performance parameters-standard curve linearity, detection limit and measurement precision-were evaluated. ddPCR in comparison with qPCR has demonstrated sufficient sensitivity for analysing of cffDNA and determination of fetal RhD status from maternal circulation, results of both methods strongly correlated. Despite the more demanding workflow, ddPCR was found to be slightly more precise technology, as evaluated using quantitative standard. Regarding the clinical samples, the precision of both methods equalized with decreasing concentrations of tested DNA samples. In case of cffDNA with very low concentrations, variance parameters of both techniques were comparable. Detected levels of fetal cfDNA in maternal plasma were slightly higher than expected and correlated significantly with gestational age as measured by both methods (ddPCR r = 0.459; qPCR r = 0.438.

  16. Does digital mammography in a decentralized breast cancer screening program lead to screening performance parameters comparable with film-screen mammography?

    International Nuclear Information System (INIS)

    Ongeval, Chantal van; Steen, Andre van; Zanca, Federica; Bosmans, Hilde; Marchal, Guy; Putte, Gretel vande; Limbergen, Erik van

    2010-01-01

    To evaluate if the screening performance parameters of digital mammography (DM) in a decentralized screening organization were comparable with film-screen mammography (FSM). A nationwide screening program was launched in 2001, and since 2005 screening with DM has been allowed. Firstly, the parameters of the three regional screening units (RSUs) that first switched to DM (11,355 women) were compared with the FSM period of the same three RSUs (23,325 women). Secondly, they were compared with the results of the whole central breast unit (CBU). The recall rate (RR) of the DM group in the initial round was 2.64% [2.40% for FSM (p = 0.43)] and in the subsequent round 1.20% [1.58% for FSM (p = 0.03)]. The cancer detection rate (CDR) was 0.59% for DM and 0.64% for FSM (p = 0.56). The percentage of ductal carcinoma in situ was 0.07% for DM and 0.16% for FSM (p = 0.02). The positive predictive value was high in the subsequent rounds (DM 48.00%, FSM 45.93%) and lower in the initial round (DM 24.05%, FSM 24.86%). Compared with the results of the whole CBU, DM showed no significant difference. DM can be introduced in a decentralized screening organization with a high CDR without increasing the RR. (orig.)

  17. The digital Emily project: achieving a photorealistic digital actor.

    Science.gov (United States)

    Alexander, Oleg; Rogers, Mike; Lambeth, William; Chiang, Jen-Yuan; Ma, Wan-Chun; Wang, Chuan-Chang; Debevec, Paul

    2010-01-01

    The Digital Emily Project uses advanced face scanning, character rigging, performance capture, and compositing to achieve one of the world's first photorealistic digital facial performances. The project scanned the geometry and reflectance of actress Emily O'Brien's face in 33 poses, showing different emotions, gaze directions, and lip formations in a light stage. These high-resolution scans-accurate to skin pores and fine wrinkles-became the basis for building a blendshape-based facial-animation rig whose expressions closely matched the scans. The blendshape rig drove displacement maps to add dynamic surface detail. A video-based facial animation system animated the face according to the performance in a reference video, and the digital face was tracked onto the video's motion and rendered under the same illumination. The result was a realistic 3D digital facial performance credited as one of the first to cross the "uncanny valley" between animated and fully human performances.

  18. Digital Creativity

    DEFF Research Database (Denmark)

    Petersson Brooks, Eva; Brooks, Anthony Lewis

    2014-01-01

    This paper reports on a study exploring the outcomes from children’s play with technology in early childhood learning practices. The paper addresses questions related to how digital technology can foster creativity in early childhood learning environments. It consists of an analysis of children......’s interaction with the KidSmart furniture focusing on digital creativity potentials and play values suggested by the technology. The study applied a qualitative approach and included125 children (aged three to five), 10 pedagogues, and two librarians. The results suggests that educators should sensitively...... consider intervening when children are interacting with technology, and rather put emphasize into the integration of the technology into the environment and to the curriculum in order to shape playful structures for children’s digital creativity....

  19. Digital radiography

    International Nuclear Information System (INIS)

    Rath, M.; Lissner, J.; Rienmueller, R.; Haendle, J.; Siemens A.G., Erlangen

    1984-01-01

    Using a prototype of an electronic, universal examination unit equipped with a special X-ray TV installation, spotfilm exposures and digital angiographies with high spatial resolution and wide-range contrast could be made in the clinic for the first time. With transvenous contrast medium injection, the clinical results of digital angiography show excellent image quality in the region of the carotids and renal arteries as well as the arteries of the extremities. The electronic series exposures have an image quality almost comparable to the quality obtained with cutfilm changers in conventional angiography. There are certain limitations due to the input field of 25 cm X-ray image intensified used. In respect of the digital angiography imaging technique, the electronic universal unit is fully suitable for clinical application. (orig.) [de

  20. Digital switched hydraulics

    Science.gov (United States)

    Pan, Min; Plummer, Andrew

    2018-06-01

    This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems (SIHSs). The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

  1. Dynamic digitized cerebral parenchymography

    International Nuclear Information System (INIS)

    Theron, J.; Alachkar, F.; Nelson, M.; Mazia, D.

    1992-01-01

    Aortic arch injections centred on the head have been performed routinely in patients with cerebral ischaemia. Digital angiograms with modified windowing (low and narrow) have been used. This 'cerebral' arch injection allows much improved analysis of the cerebral parenchymal vascularization, giving better understanding of hemispheric ischaemia and making the decision about revascularization more rational. (orig.)

  2. SAFARI digital processing unit: performance analysis of the SpaceWire links in case of a LEON3-FT based CPU

    Science.gov (United States)

    Giusi, Giovanni; Liu, Scige J.; Di Giorgio, Anna M.; Galli, Emanuele; Pezzuto, Stefano; Farina, Maria; Spinoglio, Luigi

    2014-08-01

    SAFARI (SpicA FAR infrared Instrument) is a far-infrared imaging Fourier Transform Spectrometer for the SPICA mission. The Digital Processing Unit (DPU) of the instrument implements the functions of controlling the overall instrument and implementing the science data compression and packing. The DPU design is based on the use of a LEON family processor. In SAFARI, all instrument components are connected to the central DPU via SpaceWire links. On these links science data, housekeeping and commands flows are in some cases multiplexed, therefore the interface control shall be able to cope with variable throughput needs. The effective data transfer workload can be an issue for the overall system performances and becomes a critical parameter for the on-board software design, both at application layer level and at lower, and more HW related, levels. To analyze the system behavior in presence of the expected SAFARI demanding science data flow, we carried out a series of performance tests using the standard GR-CPCI-UT699 LEON3-FT Development Board, provided by Aeroflex/Gaisler, connected to the emulator of the SAFARI science data links, in a point-to-point topology. Two different communication protocols have been used in the tests, the ECSS-E-ST-50-52C RMAP protocol and an internally defined one, the SAFARI internal data handling protocol. An incremental approach has been adopted to measure the system performances at different levels of the communication protocol complexity. In all cases the performance has been evaluated by measuring the CPU workload and the bus latencies. The tests have been executed initially in a custom low level execution environment and finally using the Real- Time Executive for Multiprocessor Systems (RTEMS), which has been selected as the operating system to be used onboard SAFARI. The preliminary results of the carried out performance analysis confirmed the possibility of using a LEON3 CPU processor in the SAFARI DPU, but pointed out, in agreement

  3. Digital photogrammetry

    CERN Document Server

    Egels, Yves

    2003-01-01

    Photogrammetry is the use of photography for surveying primarily and is used for the production of maps from aerial photographs. Along with remote sensing, it represents the primary means of generating data for Geographic Information Systems (GIS). As technology develops, it is becoming easier to gain access to it. The cost of digital photogrammetric workstations are falling quickly and these new tools are therefore becoming accessible to more and more users. Digital Photogrammetry is particularly useful as a text for graduate students in geomantic and is also suitable for people with a good basic scientific knowledge who need to understand photogrammetry, and who wish to use the book as a reference.

  4. Digital Marketing

    OpenAIRE

    Jerry Wind; Vijay Mahajan

    2002-01-01

    The digital revolution has shaken marketing to its core with consumers being offered greater price transparency and often even the chance to dictate the price. What does pricing mean in a world in which customers propose their own prices (as at priceline.com) or buyers and sellers haggle independently in auctions (as at e-Bay)? The most significant changes in the digital marketing show the emergence of 'cyber consumers', the cyber business-to-business world and the changing reality of an incr...

  5. Digital "X"

    DEFF Research Database (Denmark)

    Baiyere, Abayomi; Grover, Varun; Gupta, Alok

    2017-01-01

    Interest in using digital before existing research concepts seem to be on the rise in the IS field. This panel is positioned to explore what value lies in labelling our research as digital “x” as opposed to the well established IT “x” (where “x” can be strategy, infrastructure, innovation, artifa...... between this stream of research and existing research. Central among the expected output of the panel is the advancement of suggestions for future research and the critical pitfalls to avoid in doing so....

  6. Digital Radiography

    Science.gov (United States)

    1986-01-01

    System One, a digital radiography system, incorporates a reusable image medium (RIM) which retains an image. No film is needed; the RIM is read with a laser scanner, and the information is used to produce a digital image on an image processor. The image is stored on an optical disc. System allows the radiologist to "dial away" unwanted images to compare views on three screens. It is compatible with existing equipment and cost efficient. It was commercialized by a Stanford researcher from energy selective technology developed under a NASA grant.

  7. Digital filters

    CERN Document Server

    Hamming, Richard W

    1997-01-01

    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  8. Digital voltmeter

    International Nuclear Information System (INIS)

    Yohannes Kamadi; Soekarno.

    1976-01-01

    The electrical voltage measuring equipment with digital display has been made. This equipment uses four digits display with single polarity measurement and integrating system. Pulses from the oscillator will be counted and converted to the staircase voltages, and compared to the voltage measured. When the balance is already achieved, the pulse will appear at the comparator circuit. This pulse will be used to trigger univibrator circuit. The univibrator output is used as signal for stopping the counting, and when reading time T already stops, the counting system will be reset. (authors)

  9. Digital communication

    CERN Document Server

    Das, Apurba

    2010-01-01

    ""Digital Communications"" presents the theory and application of the philosophy of Digital Communication systems in a unique but lucid form. This book inserts equal importance to the theory and application aspect of the subject whereby the authors selected a wide class of problems. The Salient features of the book are: the foundation of Fourier series, Transform and wavelets are introduces in a unique way but in lucid language; the application area is rich and resemblance to the present trend of research, as we are attached with those areas professionally; a CD is included which contains code

  10. Digital literacies

    CERN Document Server

    Hockly, Nicky; Pegrum, Mark

    2014-01-01

    Dramatic shifts in our communication landscape have made it crucial for language teaching to go beyond print literacy and encompass the digital literacies which are increasingly central to learners' personal, social, educational and professional lives. By situating these digital literacies within a clear theoretical framework, this book provides educators and students alike with not just the background for a deeper understanding of these key 21st-century skills, but also the rationale for integrating these skills into classroom practice. This is the first methodology book to address not jus

  11. Digital computers in action

    CERN Document Server

    Booth, A D

    1965-01-01

    Digital Computers in Action is an introduction to the basics of digital computers as well as their programming and various applications in fields such as mathematics, science, engineering, economics, medicine, and law. Other topics include engineering automation, process control, special purpose games-playing devices, machine translation and mechanized linguistics, and information retrieval. This book consists of 14 chapters and begins by discussing the history of computers, from the idea of performing complex arithmetical calculations to the emergence of a modern view of the structure of a ge

  12. Digital luminecence radiography

    International Nuclear Information System (INIS)

    Erlemann, R.; Adolph, J.M.G.; Reuther, G.; Wiesmann, W.; Fervers, J.; Vestring, T.; Roos, N.; Peters, P.E.

    1990-01-01

    This paper reports on the value of contrast post processing with DLR (2.5 lp/mm; gray-scale, 10 bit) evaluated in myelography (decision making depends more on image contrast than on spatial resolution). DLR was compared with conventional myelography by means of ROC methodology. Ninety-five conventional (CR), digital (DR), and edge- enhanced digital (EDR) myelographic images (49 disk herniations, 46 normal) were read independently by five board-certified radiologists with no clinical information. Findings were scored using a 5-point confidence-scale, and an ROC analysis was performed based on CT-myelography as the gold standard

  13. The asynchronous rapid single-flux quantum electronics ─ a promising alternative for the development of high-performance digital circuits

    Directory of Open Access Journals (Sweden)

    S. Terzieva

    2008-05-01

    Full Text Available In this paper, we investigate the application of the asynchronous logic approach for the realization of ultra high-speed digital electronics with high complexity. We evaluate the possible physical, technological, and schematical origins of restrictions limiting such an application, and propose solutions for their overcoming. Although our considerations are based on the rapid single-flux quantum technique, the conclusions derived can be generalized about any type of digital information coding.

  14. CEA SMAD 2016 Digitizer Evaluation.

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Bion J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    Sandia National Laboratories has tested and evaluated an updated SMAD digitizer, developed by the French Alternative Energies and Atomic Energy Commission (CEA). The SMAD digitizers are intended to record sensor output for seismic and infrasound monitoring applications. The purpose of this digitizer evaluation is to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self-noise, dynamic range, system noise, response, passband, and timing. The SMAD digitizers have been updated since their last evaluation by Sandia to improve their performance when recording at a sample rate of 20 Hz for infrasound applications and 100 Hz for hydro-acoustic seismic stations. This evaluation focuses primarily on the 20 Hz and 100 Hz sample rates. The SMAD digitizers are being evaluated for potential use in the International Monitoring System (IMS) of the Comprehensive Nuclear Test- Ban-Treaty Organization (CTBTO).

  15. Digital delicacies

    OpenAIRE

    Holley, Rose

    2001-01-01

    This presentation outlines the purpose and work of the newly appointed Digital Projects Librarian at the University of Auckland. It gives a brief overview of what digitisation is, the benefits, the stages of a digitisation project and also samples of interesting international digitisation projects and new University of Auckland Library Digitisation projects.

  16. Digital Forensics

    Science.gov (United States)

    Harron, Jason; Langdon, John; Gonzalez, Jennifer; Cater, Scott

    2017-01-01

    The term forensic science may evoke thoughts of blood-spatter analysis, DNA testing, and identifying molds, spores, and larvae. A growing part of this field, however, is that of digital forensics, involving techniques with clear connections to math and physics. This article describes a five-part project involving smartphones and the investigation…

  17. Digital Disruption

    DEFF Research Database (Denmark)

    Rosenstand, Claus Andreas Foss

    det digitale domæne ud over det niveau, der kendetegner den nuværende debat, så præsenteres der ny viden om digital disruption. Som noget nyt udlægges Clayton Christens teori om disruptiv innovation med et særligt fokus på små organisationers mulighed for eksponentiel vækst. Specielt udfoldes...... forholdet mellem disruption og den stadig accelererende digitale udvikling i konturerne til ny teoridannelse om digital disruption. Bogens undertitel ”faretruende og fascinerende forandringer” peger på, at der er behov for en nuanceret debat om digital disruption i modsætning til den tone, der er slået an i...... videre kalder et ”disruption-råd”. Faktisk er rådet skrevet ind i 2016 regeringsgrundlaget for VLK-regeringen. Disruption af organisationer er ikke et nyt fænomen; men hastigheden, hvormed det sker, er stadig accelererende. Årsagen er den globale mega-trend: Digitalisering. Og derfor er specielt digital...

  18. Digital books.

    Science.gov (United States)

    Wink, Diane M

    2011-01-01

    In this bimonthly series, the author examines how nurse educators can use the Internet and Web-based computer technologies such as search, communication, and collaborative writing tools; social networking and social bookmarking sites; virtual worlds; and Web-based teaching and learning programs. This article describes digital books.

  19. Digital forvaltning

    DEFF Research Database (Denmark)

    Remmen, Arne; Larsen, Torben; Mosgaard, Mette

    2004-01-01

    Større effektivitet, bedre service og mere demokrai er blot nogle af forventningerne til indførelse af digital forveltning i kommunerne. Kapitlet giver bland andet svar på spørgsmålene : Hvordan lever kommunerne op hertil i dagligdagen? hvilke virkemidler anvender de? Hvilke barrierer har der været...

  20. Digital Methods

    NARCIS (Netherlands)

    Rogers, R.

    2013-01-01

    In Digital Methods, Richard Rogers proposes a methodological outlook for social and cultural scholarly research on the Web that seeks to move Internet research beyond the study of online culture. It is not a toolkit for Internet research, or operating instructions for a software package; it deals

  1. New directions in pediatric digital imaging

    International Nuclear Information System (INIS)

    Fletcher, B.D.; Adams, R.B.; Blackham, W.C.

    1985-01-01

    In this chapter the authors describe several simple experiments performed utilizing digital equipment which apply to clinical situations in pediatrics and which suggest future directions for research in digital imaging. They also discuss experimental systems which they believe will overcome certain limitations of current equipment and might be applicable to pediatric digital imaging in the future

  2. Digital Marketing and the Pillars of Shopper Experience

    OpenAIRE

    NEGRICEA, Costel Iliuta; PURCAREA, Ioan Matei

    2014-01-01

    We already live in a world of digital empowered intelligent customers, of digital products, of digital business operations and digital competitors. The fierce competition forces firms to exploit digital technologies, to have profound knowledge, to focus on market imperatives and to demonstrate a deep commitment to these digital empowered intelligent customers that disrupts every industry. Advantaged are the companies that master relevant data flow and improve the performance of employees who ...

  3. Digital Humanities and networked digital media

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    This article discusses digital humanities and the growing diversity of digital media, digital materials and digital methods. The first section describes the humanities computing tradition formed around the interpretation of computation as a rule-based process connected to a concept of digital...... materials centred on the digitisation of non-digital, finite works, corpora and oeuvres. The second section discusses “the big tent” of contemporary digital humanities. It is argued that there can be no unifying interpretation of digital humanities above the level of studying digital materials with the help...... of software-supported methods. This is so, in part, because of the complexity of the world and, in part, because digital media remain open to the projection of new epistemologies onto the functional architecture of these media. The third section discusses the heterogeneous character of digital materials...

  4. Frontal Glutamate and γ-Aminobutyric Acid Levels and Their Associations With Mismatch Negativity and Digit Sequencing Task Performance in Schizophrenia.

    Science.gov (United States)

    Rowland, Laura M; Summerfelt, Ann; Wijtenburg, S Andrea; Du, Xiaoming; Chiappelli, Joshua J; Krishna, Nithin; West, Jeffrey; Muellerklein, Florian; Kochunov, Peter; Hong, L Elliot

    2016-02-01

    Auditory mismatch negativity (MMN) is a biomarker for schizophrenia thought to reflect glutamatergic N-methyl-d-aspartate receptor function and excitatory-inhibitory neurotransmission balance. However, the association of glutamate level with MMN has not been directly examined in patients with schizophrenia, to our knowledge. To investigate the contributions of glutamate and γ-aminobutyric acid (GABA) to MMN and digit sequencing task (DST) performance, an assessment of verbal working memory, in schizophrenia. Fifty-three control participants from the community and 45 persons with schizophrenia from outpatient clinics completed an electroencephalographic session for MMN, magnetic resonance spectroscopy for glutamate and GABA, and a DST. The study dates were July 2011 to May 2014, and the dates of our analysis were May 2014 to August 2015. Glutamate, GABA, the ratio of glutamine to glutamate, MMN amplitude, and DST. Structural equation modeling was used to test the effects of neurochemistry and MMN amplitude on DST performance. The 45 persons with schizophrenia were a mean (SD) of 37.7 (12.8) years and the control participants were 37.1 (13.1) years. The schizophrenia group had a mean (SD) of 14.7 (12.1) years of illness. Mismatch negativity amplitude (F = 4.39, P = .04) and glutamate (F = 9.69, P = .002) were reduced in the schizophrenia group. Smaller MMN amplitude was significantly associated with lower GABA level (P = .008), lower glutamate level (P = .05), and higher ratio of glutamine to glutamate (P = .003). Reduced MMN amplitude was linked to poor verbal working memory in schizophrenia (P = .002). Modeling revealed that a proxy of glutamatergic function, indexed by the ratio of glutamine to glutamate, influenced a path from the ratio of glutamine to glutamate to MMN to verbal working memory (P = .38 [root-mean-square error of approximation, P GABA in MMN and verbal working memory deficits in schizophrenia has been

  5. Digital Materia

    OpenAIRE

    Lindgren, Marcus; Richey, Emma

    2014-01-01

    Med tankar från pedagogen Montessori och filosoferna Platon och Baudrillard har detta arbete behandlat frågor om datorn och dess betydelse för en grafiker. Frågeställningen formulerades efter hand och lydde tillslut: ”Hur kan materia te sig i digital form?” Forskningen resulterade i en hypotes för hur digital materia skulle födas i datorn: genom att blanda två uppsättningar av data, såsom två genuppsättningar tillsammans skapar en ny organism. Under produktionen utvecklades därmed en metod fö...

  6. Digital resources

    Directory of Open Access Journals (Sweden)

    Redazione Reti Medievali (a cura di

    2005-12-01

    Full Text Available Bibliotheca Latinitatis Mediaevalis (circa VII sec. - XIV sec. IntraText Digital Library [01/06] Corpus Scriptorum Latinorum. A digital library of Latin literature by David Camden [01/06] Fonti disponibili online concernenti la vita religiosa medievale Rete Vitae Religiosae Mediaevalis Studia Conectens [01/06] Fuentes del Medievo Hispanico Instituto de Historia, Consejo Superior de Investigaciones Científicas [01/06] Latin Literature Forum Romanum [01/06] Ludovico Antonio Muratori, Dissertazioni sopra le antichità italiane, 1751 Biblioteca dei Classici Italiani di Giuseppe Bonghi [01/06] Medieval Latin The Latin Library [01/06] Médiévales Presses Universitaires de Vincennes - Revues.org [01/06] Regesta imperii Deutsche Kommission für die Bearbeitung der Regesta Imperii e.V. [01/06] Suda On Line Byzantine Lexicography [01/06

  7. Digital teenagers

    Directory of Open Access Journals (Sweden)

    Rafael Conde Melguizo

    2011-12-01

    Full Text Available Espín, Manuel (Coord.(2011 Adolescentes Digitales.  Revista Estudios de Juventud, Nº 92. Marzo 2011. INJUVE, Madrid."Adolescentes digitales" se nos muestra como una obra que pretende explorar desde distintos puntos de vista la realidad de la generación conocida como “nativos digitales” (Prensky, la generación actual de adolescentes que ha crecido con internet y el mundo digital como su entorno normal de socialización.

  8. Digital Flora

    OpenAIRE

    Bunnell, Katie

    2007-01-01

    This research is concerned with developing a new business model for flexible small scale ceramic production that exploits the customisation capabilities of digital manufacturing technologies and the market potential and global connectivity of the world wide web. It is arguably of particular relevance to regional economic development in remote areas (Amin, Tomaney, Sabel) such as Cornwall where there is a culture of high quality small scale production, limited market and manufacturing opportun...

  9. An overview of digital radiography

    International Nuclear Information System (INIS)

    Aweligiba, S. A.

    2013-04-01

    The medical application of radiography has gained wider study since diagnostic radiology plays a very important role in modern medicine for fast diagnosis and therapy. Digital radiography is a relatively new technology that promises greater accuracy, lesser dose and better manipulation of patient radiology images in hospitals. In this study, a general discussion on digital radiography has been presented. The presentation focuses on the optimisation of doses to patients in the medical application of digital radiography, quality control and quality assurance. A brief presentation on performance indicators in digital radiography has also been presented. The advantages of digital radiography over the conventional film/screen system have been elaborated and its limitations are also outlined. (author)

  10. Digital citizens Digital nations: the next agenda

    NARCIS (Netherlands)

    A.W. (Bert) Mulder; M.W. (Martijn) Hartog

    2015-01-01

    DIGITAL CITIZENS CREATE A DIGITAL NATION Citizens will play the lead role as they – in the next phase of the information society – collectively create a digital nation. Personal adoption of information and communication technology will create a digital infrastructure that supports individual and

  11. Analog-to-digital conversion

    CERN Document Server

    Pelgrom, Marcel J M

    2010-01-01

    The design of an analog-to-digital converter or digital-to-analog converter is one of the most fascinating tasks in micro-electronics. In a converter the analog world with all its intricacies meets the realm of the formal digital abstraction. Both disciplines must be understood for an optimum conversion solution. In a converter also system challenges meet technology opportunities. Modern systems rely on analog-to-digital converters as an essential part of the complex chain to access the physical world. And processors need the ultimate performance of digital-to-analog converters to present the results of their complex algorithms. The same progress in CMOS technology that enables these VLSI digital systems creates new challenges for analog-to-digital converters: lower signal swings, less power and variability issues. Last but not least, the analog-to-digital converter must follow the cost reduction trend. These changing boundary conditions require micro-electronics engineers to consider their design choices for...

  12. Exploring Young Children's Performance on and Acceptance of an Educational Scenario-Based Digital Game for Teaching Route-Planning Strategies: A Case Study

    Science.gov (United States)

    Lin, Yi-Hui; Hou, Huei-Tse

    2016-01-01

    Researchers suggest that game-based learning (GBL) can be used to facilitate mathematics learning. However, empirical GBL research that targets young children is still limited. The purposes of the study is to develop a scenario-based digital game to promote children's route-planning ability, to empirically explore children's learning performance…

  13. Digital Hadron Calorimetry

    Science.gov (United States)

    Bilki, Burak

    2018-03-01

    The Particle Flow Algorithms attempt to measure each particle in a hadronic jet individually, using the detector providing the best energy/momentum resolution. Therefore, the spatial segmentation of the calorimeter plays a crucial role. In this context, the CALICE Collaboration developed the Digital Hadron Calorimeter. The Digital Hadron Calorimeter uses Resistive Plate Chambers as active media and has a 1-bit resolution (digital) readout of 1 × 1 cm2 pads. The calorimeter was tested with steel and tungsten absorber structures, as well as with no absorber structure, at the Fermilab and CERN test beam facilities over several years. In addition to conventional calorimetric measurements, the Digital Hadron Calorimeter offers detailed measurements of event shapes, rigorous tests of simulation models and various tools for improved performance due to its very high spatial granularity. Here we report on the results from the analysis of pion and positron events. Results of comparisons with the Monte Carlo simulations are also discussed. The analysis demonstrates the unique utilization of detailed event topologies.

  14. Digital image analysis of NDT radiographs

    International Nuclear Information System (INIS)

    Graeme, W.A. Jr.; Eizember, A.C.; Douglass, J.

    1989-01-01

    Prior to the introduction of Charge Coupled Device (CCD) detectors the majority of image analysis performed on NDT radiographic images was done visually in the analog domain. While some film digitization was being performed, the process was often unable to capture all the usable information on the radiograph or was too time consuming. CCD technology now provides a method to digitize radiographic film images without losing the useful information captured in the original radiograph in a timely process. Incorporating that technology into a complete digital radiographic workstation allows analog radiographic information to be processed, providing additional information to the radiographer. Once in the digital domain, that data can be stored, and fused with radioscopic and other forms of digital data. The result is more productive analysis and management of radiographic inspection data. The principal function of the NDT Scan IV digital radiography system is the digitization, enhancement and storage of radiographic images

  15. Digital Content Strategies

    OpenAIRE

    Halbheer, Daniel; Stahl, Florian; Koenigsberg, Oded; Lehmann, Donald R

    2013-01-01

    This paper studies content strategies for online publishers of digital information goods. It examines sampling strategies and compares their performance to paid content and free content strategies. A sampling strategy, where some of the content is offered for free and consumers are charged for access to the rest, is known as a "metered model" in the newspaper industry. We analyze optimal decisions concerning the size of the sample and the price of the paid content when sampling serves the dua...

  16. Digital fluorimeter

    International Nuclear Information System (INIS)

    Mello, H.A. de.

    1980-11-01

    The specifications of a digital fluorimeter. That with adequated analytical techniques permits to determine trace amounts of fluorescents materials in samples, are described. The fluorimeter is of the reflection type, and uses fluorescents lamps for the excitation and an optical system which is connected to a photomultiplyer machine and permits the measurement of the light intensity. In the case of IEN (Instituto de Engenharia Nuclear) the equipment is used for to determine the uranium content in sample materials to be exported. The precision of the instrument is about + - 1% in the scale of 0.1 which is the normally one used in the current researchs. (E.G.) [pt

  17. Digital entrepreneurship

    DEFF Research Database (Denmark)

    Brem, Alexander; Richter, Chris; Kraus, Sascha

    2017-01-01

    comprising guided interviews with 14 companies from Germany, Austria and Switzerland provides detailed insights into different aspects of the sharing economy phenomenon. Our results make a direct contribution to sharing economy research, especially regarding the new business models of start-ups. Here, we...... find a clear difference between the relevance of economic and social orientation. The latter appears to be in higher demand among customers than entrepreneurs. The increasingly digitalized environment has led to a changed living situation characterized by urbanity, openness to new solutions, changed...

  18. Focus: Digital

    DEFF Research Database (Denmark)

    Technology has been an all-important and defining element within the arts throughout the 20th century, and it has fundamentally changed the ways in which we produce and consume music. With this Focus we investigate the latest developments in the digital domain – and their pervasiveness and rapid...... production and reception of contemporary music and sound art. With ‘Digital’ we present four composers' very different answers to how technology impact their work. To Juliana Hodkinson it has become an integral part of her sonic writing. Rudiger Meyer analyses the relationships between art and design and how...

  19. Distal digital replantation.

    Science.gov (United States)

    Jazayeri, Leila; Klausner, Jill Q; Chang, James

    2013-11-01

    Hand surgeons have been hesitant to perform distal digital replantation because of the technical challenges and the perception of a high cost-to-benefit ratio. Recent studies, however, have shown high survival rates and excellent functional and aesthetic results, providing renewed enthusiasm for distal replantation. The authors reviewed the literature and summarize key points regarding the surgical treatment, perioperative care, and outcomes of distal digital replantation. They describe specific techniques and considerations for surgical repair in each of four distal zones as described by Sebastin and Chung. Zone 1A replantation involves an artery-only anastomosis of a longitudinal pulp artery. Venous anastomosis first becomes possible in zone 1B. Zone 1C involves periarticular amputations where arthrodesis of the distal interphalangeal joint is usually indicated. Repair of the artery, vein, and nerve is technically optimal in zone 1D, where venous anastomosis should be performed. Overall, survival rates for distal digital replantation are similar to those reported for more proximal replantation. The literature reports good outcomes regarding nail salvage, fingertip sensibility, and range of motion, with restoration of length and aesthetic appearance. Distal replantation performed at institutions that specialize in microsurgery and specifically tailored to the level of injury is associated with good survival, function, and patient satisfaction and superior aesthetic outcome. More prospective data are needed to evaluate the cost of treatment, psychological outcomes, and functional outcomes of distal replantation compared with revision amputation.

  20. Digital hilar tomography. Comparison with conventional technique

    International Nuclear Information System (INIS)

    Schaefer, C.B.; Braunschweig, R.; Teufl, F.; Kaiser, W.; Claussen, C.D.

    1993-01-01

    The aim of the following study was to compare conventional hilar tomography and digital hilar tomography. 20 patients were examined both with conventional and digital hilar tomography using the same tomographic technique and the identical exposure dose. All patients underwent computed tomography of the chest as a golden standard. The digital technique, especially the edge-enhanced image version, showed superior image quality. ROC-analysis by 4 readers found equal diagnostic performance without any statistical difference. Digital hilar tomography shows a superior and constant image quality and lowers the rate of re-exposure. Therefore, digital hilar tomography is the preferable method. (orig.) [de

  1. Digital Humanities

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørn

    2015-01-01

    overgangen fra trykkekultur til digital kultur. For det første problemstillingen omkring digitalisering af litterær kulturarv med fokus på kodning og tagging af teksten samt organisering i hypertekststrukturer. For det andet reorganiseringen af det digitale dokument i dataelementer og database. For det......Artiklen præsenterer først nogle generelle problemstillinger omkring Digital Humanities (DH) med det formål at undersøge dem nærmere i relation til konkrete eksempler på forskellige digitaliseringsmåder og ændringer i dokumentproduktion. I en nærmere afgrænsning vælger artiklen den tendens i DH......, der betragter DH som forbundet med "making" og "building" af digitale objekter og former. Dette kan også karakteriseres som DH som praktisk-produktiv vending. Artiklen har valgt tre typer af digitalisering. De er valgt ud fra, at de skal repræsentere forskellige måder at håndtere digitaliseringen på...

  2. Digital radiography using scintillating screens

    International Nuclear Information System (INIS)

    Salvini, E.

    1988-01-01

    This paper briefly describes the technical features of a digital radiographic system based on the principle of scanning laser stimulated luminescence. Such aspects as the physics of the stimulable phosphor detector are dealt with, and image acquisition, processing, and hard-copy output. Automatic analysis of pixel histograms is described, in a qualitative way, together with contrast modifications and spatial filtering. Physical image characteristics are reported. The overall performance of digital radiography is examined, together with the current requirements and its eventual developments

  3. Visiting digital fluency for pre-service teachers in Turkey

    Directory of Open Access Journals (Sweden)

    Kadir Demir

    2015-04-01

    Full Text Available Digital literacy is to know how to use digital tools, however digital fluency is a new concept. Beyond the digital literacy, digital fluency requires skills to know when to use the technology and even why to use the technology. The technology advances rapidly; as a result, education and instruction are getting digitalized. So it could be estimated that; pre-service teachers who are future teachers, should have digital skills. This is the main point of this study which aims to visit pre-service teachers in Turkey from the perspective of digital fluency, give insights about digital fluency, scrutinize its difference from digital literacy and provide literature review on the previous studies about digital fluency. Accordingly; a through literature review was performed. At first, the connection between digital fluency and the 21st century analyzed, then the differences between digital literacy and digital fluency are described. Worldwide and specifically Turkish literature review revealed that, certain studies foresaw the increasing importance of digital fluency based on development of digital devices, and Turkish literature was limited to some scale development and descriptive studies solely determining the digital literacy level of the participants. Thus, it could be stated that further and up-to-date studies are required, which would be conducted with pre-service teachers and current assessment instruments should be developed to determine digital fluency level, considering the rapid advances in technology.

  4. The diagnostic accuracy of dual-view digital mammography, single-view breast tomo-synthesis and a dual-view combination of breast tomo-synthesis and digital mammography in a free-response observer performance study

    International Nuclear Information System (INIS)

    Svahn, T.; Andersson, I.; Chakraborty, D.; Svensson, S.; Ikeda, D.; Foernvik, D.; Mattsson, S.; Tingberg, A.; Zackrisson, S.

    2010-01-01

    The purpose of the present study was to compare the diagnostic accuracy of dual-view digital mammography (DM), single view breast tomo-synthesis (BT) and BT combined with the opposite DM view. Patients with subtle lesions were selected to undergo BT examinations. Two radiologists who are non-participants in the study and have experience in using DM and BT determined the locations and extents of lesions in the images. Five expert mammographers interpreted the cases using the free-response paradigm. The task was to mark and rate clinically reportable findings suspicious for malignancy and clinically relevant benign findings. The marks were scored with reference to the outlined regions into lesion localization or non-lesion localization, and analysed by the jackknife alternative free-response receiver operating characteristic method. The analysis yielded statistically significant differences between the combined modality and dual-view DM (p < 0.05). No differences were found between single-view BT and dual-view DM or between single-view BT and the combined modality. (authors)

  5. Digital radiography

    DEFF Research Database (Denmark)

    Precht, H; Gerke, O; Rosendahl, K

    2012-01-01

    BACKGROUND: New developments in processing of digital radiographs (DR), including multi-frequency processing (MFP), allow optimization of image quality and radiation dose. This is particularly promising in children as they are believed to be more sensitive to ionizing radiation than adults....... OBJECTIVE: To examine whether the use of MFP software reduces the radiation dose without compromising quality at DR of the femur in 5-year-old-equivalent anthropomorphic and technical phantoms. MATERIALS AND METHODS: A total of 110 images of an anthropomorphic phantom were imaged on a DR system (Canon DR...... with CXDI-50 C detector and MLT[S] software) and analyzed by three pediatric radiologists using Visual Grading Analysis. In addition, 3,500 images taken of a technical contrast-detail phantom (CDRAD 2.0) provide an objective image-quality assessment. RESULTS: Optimal image-quality was maintained at a dose...

  6. Fokus: Digital

    DEFF Research Database (Denmark)

    2014-01-01

    i det digitale domæne – udviklinger, der foregår hastigt og er gennemgribende, og som derfor kræver et nærmere blik på forholdet mellem kunsten og teknologien. Komponistens forståelse af sin metier udfordres – samtidig med at befæstede ideer om kunstværket møder modstand fra nye mediemæssige...... sammenhænge og fra forandrede distributionsformer. Dette betyder ændrede betingelser for både produktion og reception af kunstmusik og lydkunst. Med Digital tager vi udgangspunkt i fire komponisters meget forskellige bud på hvordan teknologien spiller en rolle i arbejdet. Juliana Hodkinson beskriver hvordan...

  7. A multi-channel waveform digitizer system

    International Nuclear Information System (INIS)

    Bieser, F.; Muller, W.F.J.

    1990-01-01

    The authors report on the design and performance of a multichannel waveform digitizer system for use with the Multiple Sample Ionization Chamber (MUSIC) Detector at the Bevalac. 128 channels of 20 MHz Flash ADC plus 256 word deep memory are housed in a single crate. Digital thresholds and hit pattern logic facilitate zero suppression during readout which is performed over a standard VME bus

  8. Digital subtraction angiography

    International Nuclear Information System (INIS)

    Gmelin, E.; Arlart, I.P.

    1987-01-01

    The introduction explains the technical and physical fundamentals of digital radiography, the principles of digital subtraction, and the various filtering methods. The authors then define the requirements to be met by a DSA equipment in terms of technical components and operational performance. A very extensive chapter deals with the indications supporting intravenous or intraarterial DSA and compares the two methods, showing advantages and drawbacks with respect to practical results. Another chapter discusses the applications of DSA for cardiological diagnostics, as e.g. imaging of the coronary arteries or arterial bypasses, and explains the densitometric and planimetric evaluation of the coronary functional processes. The book also discusses less customary applications of DSA such as the sialography or dacryocystography, as well as angiologic examinations in children. The limits of the DSA methods are discussed in the last chapter, together with aspects such as the radiation exposure of the patient, and cost-benefit analyses, and potential future improvements. With 204 figs., 44 tabs [de

  9. A digital Jewish history?

    Directory of Open Access Journals (Sweden)

    Smiatacz Carmen

    2017-06-01

    Full Text Available How can we teach Jewish history in a modern and effective way? In Hamburg, Germany, a school project called Geschichtomat tries to find an answer to that question. With the help of digital media, students explore their Jewish neighbourhood. This one-of-a-kind German program permits students to experience the Jewish past and present life in their hometown. During the project, students explore their neighbourhood to understand its historical figures, places, and events. This way they engage with Jewish life. Under the supervision of experts in the disciplines of history and media education, the students will: research, perform interviews with cultural authorities and contemporary witnesses, visit museums and archives, shoot and cut films, edit photos and write accompanying texts. Finally, their contributions are uploaded to the geschichtomat.de website. Little by little a digital map of Jewish life from the perspective of teenagers will take shape.

  10. Digital work in a digitally challenged organization

    NARCIS (Netherlands)

    Davison, R.M.; Ou, Carol

    Digitally literate employees are accustomed to having free access to digital media technologies. However, some organizations enact information technology (IT) governance structures that explicitly proscribe access to these technologies, resulting in considerable tension between employees and the

  11. USNA DIGITAL FORENSICS LAB

    Data.gov (United States)

    Federal Laboratory Consortium — To enable Digital Forensics and Computer Security research and educational opportunities across majors and departments. Lab MissionEstablish and maintain a Digital...

  12. Digital reactivity meter construction based on PC

    International Nuclear Information System (INIS)

    Yusi-Eko-Yulianto; Kristedjo-Kurnianto

    2003-01-01

    The reactivitymeter is a core reactivity measuring equipment, which inform the reactor operator the neutron flux development in the core. This digital reactivitymeter is needed to replace analog reactivitymeter, whenever it fails in the future. The replacement of thus reactivitymeter can keep the continuation of reactor operation. The digital reactivitymeter is constructed by using the digital signal processing and computer. Thus real time signal processing is displayed on the monitor graphically. This reactivitymeter has been tested in RSG-GAS and perform a good work. This performance is worthy to use this digital reactivitymeter for RSG-GAS operation

  13. Can We Teach Digital Natives Digital Literacy?

    Science.gov (United States)

    Ng, Wan

    2012-01-01

    In recent years, there has been much debate about the concept of digital natives, in particular the differences between the digital natives' knowledge and adoption of digital technologies in informal versus formal educational contexts. This paper investigates the knowledge about educational technologies of a group of undergraduate students…

  14. Modems for emerging digital cellular-mobile radio system

    Science.gov (United States)

    Feher, Kamilo

    1991-01-01

    Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

  15. Digital produktion

    DEFF Research Database (Denmark)

    Bogen sætter fokus på digital produktion, som er en stærk læringsform, der faciliterer elevernes læreprocesser og kvalificerer elevernes faglige læringsresultater. Det sker når lærerne udarbejder didaktiske rammedesign, hvor eleverne arbejder selvstændigt inden for dette rammedesign, og hvor mål og...... procesevaluering stilladserer elevernes faglige proces. I digitale produktionsprocesser arbejder eleverne iterativt, de udvikler ejerskab til produktionen og fastholder selv deres læreprocesser. It’s multimodalitet, elevernes kollaborative tilgange, videndeling mellem eleverne og elevernes uformelle lege- og...... elevernes digitale produktion er lærernes didaktiske rammesætning og stilladserende tilgange. Her lægger lærerne op til, at eleverne som didaktiske designere i relation til rammesætningen skal organisere og planlægge deres læreprocesser, inddrages i målsætning, evaluering og valg af digitale ressourcer...

  16. Digital dannelse

    DEFF Research Database (Denmark)

    Bundsgaard, Jeppe

    2012-01-01

    I al vores iver efter at få presset nogle flere digitale dimser ind i skolen, er vi i fare for at glemme hvad det er vi skal med disse dimser. Der er store forventninger til at de kan gøre det lettere at være lærer (og dermed billigere), og det kan det måske. Men der er jo også et dannelsesspørgs......I al vores iver efter at få presset nogle flere digitale dimser ind i skolen, er vi i fare for at glemme hvad det er vi skal med disse dimser. Der er store forventninger til at de kan gøre det lettere at være lærer (og dermed billigere), og det kan det måske. Men der er jo også et...... dannelsesspørgsmål knyttet til it. Hvad er egentlig digital dannelse? Og hvad betyder det for danskfaget?...

  17. Digital forensics digital evidence in criminal investigations

    CERN Document Server

    Marshall, Angus McKenzie

    2009-01-01

    The vast majority of modern criminal investigations involve some element of digital evidence, from mobile phones, computers, CCTV and other devices. Digital Forensics: Digital Evidence in Criminal Investigations provides the reader with a better understanding of how digital evidence complements "traditional" scientific evidence and examines how it can be used more effectively and efficiently in a range of investigations. Taking a new approach to the topic, this book presents digital evidence as an adjunct to other types of evidence and discusses how it can be deployed effectively in s

  18. Digital neutron dosimeter

    International Nuclear Information System (INIS)

    Ramondetta, P.W.; Groeber, E.O.Jr.

    1978-01-01

    Design features for a portable battery-operated neutron dosimeter are described. The system employs a 50-mil PIN detector diode, whose forward voltage increases with exposure to fast neutrons. Because this change is permanent and cumulative, the system is able to integrate small doses (from 0 to 1000 rad) over long periods of time. The system is temperature compensated over its operating range of -40 C to +52C. Display accuracies of +-20 rad for readings below 100 rad and +-20% for readings above 100 rad are maintained throughout the range. Temperature correction is performed digitally after an initial analog-to-digital conversion of both the forward diode voltage and the ambient temperature. System flexibility is promoted with the use of a replaceable ROM for the final voltage-to-dose conversion table. This digital approach to temperature compensation, combined with the extensive use of CMOS circuitry, suggests the use of custom large-scale integration as a means of further reducing system weight and size. This possibility, as well as others, is discussed as a means of reducing system size. Test and evaluation results are also included. (author)

  19. Digital stereoscopic imaging

    Science.gov (United States)

    Rao, A. Ravishankar; Jaimes, Alejandro

    1999-05-01

    The convergence of inexpensive digital cameras and cheap hardware for displaying stereoscopic images has created the right conditions for the proliferation of stereoscopic imagin applications. One application, which is of growing importance to museums and cultural institutions, consists of capturing and displaying 3D images of objects at multiple orientations. In this paper, we present our stereoscopic imaging system and methodology for semi-automatically capturing multiple orientation stereo views of objects in a studio setting, and demonstrate the superiority of using a high resolution, high fidelity digital color camera for stereoscopic object photography. We show the superior performance achieved with the IBM TDI-Pro 3000 digital camera developed at IBM Research. We examine various choices related to the camera parameters, image capture geometry, and suggest a range of optimum values that work well in practice. We also examine the effect of scene composition and background selection on the quality of the stereoscopic image display. We will demonstrate our technique with turntable views of objects from the IBM Corporate Archive.

  20. Digital platforms as enablers for digital transformation

    DEFF Research Database (Denmark)

    Hossain, Mokter; Lassen, Astrid Heidemann

    transformation is crucial. This study aims at exploring how organizations are driven towards transformation in various ways to embrace digital platforms for ideas, technologies, and knowledge. It shows the opportunities and challenges digital platforms bring in organizations. It also highlights underlying......Digital platforms offer new ways for organizations to collaborate with the external environment for ideas, technologies, and knowledge. They provide new possibilities and competence but they also bring new challenges for organizations. Understanding the role of these platforms in digital...... mechanisms and potential outcomes of various digital platforms. The contribution of the submission is valuable for scholars to understand and further explore this area. It provides insight for practitioners to capture value through digital platforms and accelerate the pace of organizations’ digital...

  1. H. Sapiens Digital: From Digital Immigrants and Digital Natives to Digital Wisdom

    Science.gov (United States)

    Prensky, Marc

    2009-01-01

    As we move further into the 21st century, the digital native/digital immigrant paradigm created by Marc Prensky in 2001 is becoming less relevant. In this article, Prensky suggests that we should focus instead on the development of what he calls "digital wisdom." Arguing that digital technology can make us not just smarter but truly wiser, Prensky…

  2. Dual beam vidicon digitizer

    International Nuclear Information System (INIS)

    Evans, T.L.

    1976-01-01

    A vidicon waveform digitizer which can simultaneously digitize two independent signals has been developed. Either transient or repetitive waveforms can be digitized with this system. A dual beam oscilloscope is used as the signal input device. The light from the oscilloscope traces is optically coupled to a television camera, where the signals are temporarily stored prior to digitizing

  3. Digital mammography in breast cancer screening: Evaluation and innovation

    NARCIS (Netherlands)

    Bluekens, A.M.J.

    2015-01-01

    With all other imaging modalities in radiology being digitised and conventional mammography being ready to phase out the transition to digital mammography was inevitable. This thesis describes the performance of digital screening mammography and the consequences of implementation in a

  4. Enabling Digital Literacy

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Georgsen, Marianne

    2010-01-01

    There are some tensions between high-level policy definitions of “digital literacy” and actual teaching practice. We need to find workable definitions of digital literacy; obtain a better understanding of what digital literacy might look like in practice; and identify pedagogical approaches, which...... support teachers in designing digital literacy learning. We suggest that frameworks such as Problem Based Learning (PBL) are approaches that enable digital literacy learning because they provide good settings for engaging with digital literacy. We illustrate this through analysis of a case. Furthermore......, these operate on a meso-level mediating between high-level concepts of digital literacy and classroom practice....

  5. Progress in digital radiography

    International Nuclear Information System (INIS)

    Cappelle, A.

    2016-01-01

    Because of its practical aspect digital radiography is more and more used in the industrial sector. There are 2 kinds of digital radiography. First, the 'computed radiography' that uses a photon-stimulated screen, and after radiation exposure this screen must be read by an analyser to get a digit image. The second type is the 'direct radiography' that allows one to get a digit radiograph of the object directly. Digital radiography uses the same radioactive nuclides as radiography with silver films: cobalt, iridium or selenium. The spatial resolution of digital radiography is less good than with classical silver film radiography but digital radiography offers a better visual contrast. (A.C.)

  6. Land Treatment Digital Library

    Science.gov (United States)

    Pilliod, David S.; Welty, Justin L.

    2013-01-01

    The Land Treatment Digital Library (LTDL) was created by the U.S. Geological Survey to catalog legacy land treatment information on Bureau of Land Management lands in the western United States. The LTDL can be used by federal managers and scientists for compiling information for data-calls, producing maps, generating reports, and conducting analyses at varying spatial and temporal scales. The LTDL currently houses thousands of treatments from BLM lands across 10 states. Users can browse a map to find information on individual treatments, perform more complex queries to identify a set of treatments, and view graphs of treatment summary statistics.

  7. DYMAC digital electronic balance

    International Nuclear Information System (INIS)

    Stephens, M.M.

    1980-06-01

    The Dynamic Materials Accountability (DYMAC) System at LASL integrates nondestructive assay (NDA) instruments with interactive data-processing equipment to provide near-real-time accountability of the nuclear material in the LASL Plutonium Processing Facility. The most widely used NDA instrument in the system is the DYMAC digital electronic balance. The DYMAC balance is a commercial instrument that has been modified at LASL for weighing material in gloveboxes and for transmitting the weight data directly to a central computer. This manual describes the balance components, details the LASL modifications, reviews a DYMAC measurement control program that monitors balance performance, and provides instructions for balance operation and maintenance

  8. Single Event Upset Analysis: On-orbit performance of the Alpha Magnetic Spectrometer Digital Signal Processor Memory aboard the International Space Station

    Science.gov (United States)

    Li, Jiaqiang; Choutko, Vitaly; Xiao, Liyi

    2018-03-01

    Based on the collection of error data from the Alpha Magnetic Spectrometer (AMS) Digital Signal Processors (DSP), on-orbit Single Event Upsets (SEUs) of the DSP program memory are analyzed. The daily error distribution and time intervals between errors are calculated to evaluate the reliability of the system. The particle density distribution of International Space Station (ISS) orbit is presented and the effects from the South Atlantic Anomaly (SAA) and the geomagnetic poles are analyzed. The impact of solar events on the DSP program memory is carried out combining data analysis and Monte Carlo simulation (MC). From the analysis and simulation results, it is concluded that the area corresponding to the SAA is the main source of errors on the ISS orbit. Solar events can also cause errors on DSP program memory, but the effect depends on the on-orbit particle density.

  9. Diagnostic accuracy of fracture detection in suspected non-accidental injury: the effect of edge enhancement and digital display on observer performance

    Energy Technology Data Exchange (ETDEWEB)

    Offiah, A.C. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom) and Institute of Child Health, London (United Kingdom)]. E-mail: amaka.offiah@gosh.nhs.uk; Moon, L. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Hall, C.M. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Todd-Pokropek, A. [Department of Medical Physics and Bioengineering, University College London, London (United Kingdom)

    2006-02-15

    AIM: To compare the effect of varying degrees of edge enhancement and method of digital image display on fracture detection in suspected non-accidental injury (NAI). MATERIALS AND METHODS: Fifty radiographs from post-mortem skeletal surveys in 13 children with suspected NAI were selected. Images were obtained using a Fuji 5000R computed radiography system. Hard copies were printed with edge enhancement factors 0, 0.5 and 1.2. Images (edge enhancement 0.5) were also displayed on a 1K{sup 2} monitor. Six observers independently evaluated all 200 images for the presence of abnormality. Observers also scored each image for visualization of soft tissues, visualization of trabecular markings and overall image quality. The paired Student's t-test and location receiver operating curve (ROC) analysis were used to compare quality scores and diagnostic accuracy of each display method. Individual and pooled true-positive rates (sensitivity) were determined. For the purposes of ROC analysis, histology was taken as the gold standard. RESULTS: There was no difference in duration of hard and soft-copy reading sessions (p=0.76). After image manipulation soft-copy radiographs scored significantly better for image quality than hard copy (p<0.0001). Pooled observer sensitivity (at a specificity of 90%) was below 50% for all display methods. Diagnostic accuracy varied significantly between observers. Diagnostic accuracy of individual observers was not affected by display method. CONCLUSION: In suspected NAI, diagnostic accuracy of fracture detection is generally low. Diagnostic accuracy appears to be affected more by observer-related factors than by the method of digital image display.

  10. Monitoring the digital divide

    International Nuclear Information System (INIS)

    Canessa, E.; Cerdeira, H.A.; Matthews, W.; Cottrell, R.L.

    2003-05-01

    It is increasingly important to support the large numbers of scientists working in remote areas and having low-bandwidth access to the Internet. This will continue to be the case for years to come since there is evidence from PingER performance measurements that the, so-called, digital divide is not decreasing. In this work, we review the collaborative work of The Abdus Salam International Center for Theoretical Physics (ICTP) in Trieste - a leading organization promoting science dissemination in the developing world- and SLAC in Stanford, to monitor by PingER, Universities and Research Institutions all over the developing world following the recent 'Recommendations of Trieste' to help bridge the digital divide. As a result, PingER's deployment now covers the real-time monitoring of worldwide Internet performance and, in particular, West and Central Africa for the first time. We report on the results from the ICTP sites and quantitatively identify regions with poor performance, identify trends, discuss experiences and future work. (author)

  11. Monitoring the Digital Divide

    International Nuclear Information System (INIS)

    Cottrell, Les

    2003-01-01

    It is increasingly important to support the large numbers of scientists working in remote areas and having low bandwidth access to the Internet. This will continue to be the case for years to come since there is evidence from PingER performance measurements that the, so-called, digital divide is not decreasing. In this work, we review the collaborative work of The Abdus Salam International Center for Theoretical Physics (ICTP) in Trieste, a leading organization promoting science dissemination in the developing world- and SLAC in Stanford, to monitor by PingER, Universities and Research Institutions all over the developing world following the recent ''Recommendations of Trieste'' to help bridge the digital divide. As a result, PingER's deployment now covers the real-time monitoring of worldwide Internet performance and, in particular, West and Central Africa for the first time. We report on the results from the ICTP sites and quantitatively identify regions with poor performance, identify trends, discuss experiences and future work

  12. Digital Sensor Technology

    Energy Technology Data Exchange (ETDEWEB)

    Ted Quinn; Jerry Mauck; Richard Bockhorst; Ken Thomas

    2013-07-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy, reliability, availability, and maintainability. This report demonstrates these benefits in direct comparisons of digital and analog sensor applications. It also addresses the qualification issues that must be addressed in the application of digital sensor technology.

  13. Digital preservation for heritages

    CERN Document Server

    Lu, Dongming

    2011-01-01

    ""Digital Preservation for Heritages: Technologies and Applications"" provides a comprehensive and up-to-date coverage of digital technologies in the area of cultural heritage preservation, including digitalization, research aiding, conservation aiding, digital exhibition, and digital utilization. Processes, technical frameworks, key technologies, as well as typical systems and applications are discussed in the book. It is intended for researchers and students in the fields of computer science and technology, museology, and archaeology. Dr. Dongming Lu is a professor at College of Computer Sci

  14. Examining Factors Predicting Students’ Digital Competence

    Directory of Open Access Journals (Sweden)

    Ove Edvard Hatlevik

    2015-02-01

    Full Text Available The purpose of this study was to examine factors predicting lower secondary school students’ digital competence and to explore differences between students when it comes to digital competence. Results from a digital competence test and survey in lower secondary school will be presented. It is important to learn more about and investigate what characterizes students’ digital competence. A sample of 852 ninth-grade Norwegian students from 38 schools participated in the study. The students answered a 26 item multiple-choice digital competence test and a self-report questionnaire about family background, motivation, and previous grades. Structural equation modeling was used to test a model of the hypothesised relationship between family background, mastery orientation, previous achievements, and digital competence. The results indicate variation in digital competence among the ninth-graders. Further, analyses showed that students’ conditions at home, i.e., language integration and cultural capital, together with mastery orientation and academic achievements predict students digital competence. This study indicates that that there is evidence of digital diversity between lower secondary students. It does not seem like the development of digital competence among the students happens automatically. Students’ family background and school performance are the most important factors. Therefore, as this study shows, it is necessary to further investigate how schools can identify students’ level of competence and to develop plans and actions for how schools can help to try to equalize differences.

  15. Digital Literacy and New Technological Perspectives

    Science.gov (United States)

    Feola, Elvia Ilaria

    2016-01-01

    This paper aims to reflect on the implications and challenges that experts in the field have to deal with when you want to evaluate the performance in the use of digital technologies in teaching. The argument stems from a contextual and social assessment, and then proceeds to an application and methodological connotation of digital literacy…

  16. Using Digital Texts to Promote Fluent Reading

    Science.gov (United States)

    Thoermer, Andrea; Williams, Lunetta

    2012-01-01

    Fluency is a critical skill of adept readers. As listening to read alouds and performing Readers Theatre scripts are two prevalent strategies that can increase students' fluency skills, this article provides suggestions in using these strategies with digital texts through free, online resources. Digital texts can be accessed using a desktop,…

  17. Cognitive Hacking and Digital Government: Digital Identity

    OpenAIRE

    Paul Thompson

    2004-01-01

    Recently the National Center for Digital Government held a workshop on "The Virtual Citizen: Identity, Autonomy, and Accountability: A Civic Scenario Exploration of the Role of Identity in On-Line. Discussions at the workshop focused on five scenarios for future authentication policies with respect to digital identity. The underlying technologies considered for authentication were: biometrics: cryptography, with a focus on digital signatures; secure processing/computation; and reputation syst...

  18. Digital Materialisms: Frameworks for Digital Media Studies

    OpenAIRE

    Casemajor, Nathalie

    2015-01-01

    Since the 1980s, digital materialism has received increasing interest in the field of media studies. Materialism as a theoretical paradigm assumes that all things in the world are tied to physical processes and matter. Yet within digital media studies, the understanding of what should be the core object of a materialist analysis is debated. This paper proposes to untangle some of the principal theoretical propositions that compose the field of digital materialism. It outlines six frameworks t...

  19. Digital Data Processing of Images

    African Journals Online (AJOL)

    Digital data processing was investigated to perform image processing. Image smoothing and restoration were explored and promising results obtained. The use of the computer, not only as a data management device, but as an important tool to render quantitative information, was illustrated by lung function determination.

  20. Performance of high-temperature superconducting band-pass filters with high selectivity for base transceiver applications of digital cellular communication systems

    Science.gov (United States)

    Kwak, J. S.; Lee, J. H.; Kim, C. O.; Hong, J. P.; Han, S. K.; Char, K.

    2002-07-01

    Highly selective high-temperature superconducting band-pass filters based on spiral meander line structures have been developed for base transceiver station applications of digital cellular communication systems. The filter comprised 12-pole microstrip line resonators with a circuit size of 0.5 × 17 × 41 mm3. The filter was designed to have a bandwidth of 25 MHz at a centre frequency of 834 MHz. Particularly, the physical size of each resonator was chosen not only to reduce far-field radiation, but also to have reasonable tunability in the filter. Device characteristics exhibited a low insertion loss of 0.4 dB with a 0.2 dB ripple and a return loss better than 10 dB in the pass-band at 65 K. The out-of-band signals were attenuated better than 60 dB at about 3.5 MHz from the lower band edge, and 3.8 MHz from the higher band edge.

  1. Performance of high-temperature superconducting band-pass filters with high selectivity for base transceiver applications of digital cellular communication systems

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, J.S.; Lee, J.H.; Kim, C.O.; Hong, J.P. [Department of Physics, Hanyang University, Seoul (Korea, Republic of); Han, S.K.; Char, K. [RFtron Inc., Seoul (Korea, Republic of)

    2002-07-01

    Highly selective high-temperature superconducting band-pass filters based on spiral meander line structures have been developed for base transceiver station applications of digital cellular communication systems. The filter comprised 12-pole microstrip line resonators with a circuit size of 0.5x17x41 mm{sup 3}. The filter was designed to have a bandwidth of 25 MHz at a centre frequency of 834 MHz. Particularly, the physical size of each resonator was chosen not only to reduce far-field radiation, but also to have reasonable tunability in the filter. Device characteristics exhibited a low insertion loss of 0.4 dB with a 0.2 dB ripple and a return loss better than 10 dB in the pass-band at 65 K. The out-of-band signals were attenuated better than 60 dB at about 3.5 MHz from the lower band edge, and 3.8 MHz from the higher band edge. (author)

  2. Performance of high-temperature superconducting band-pass filters with high selectivity for base transceiver applications of digital cellular communication systems

    International Nuclear Information System (INIS)

    Kwak, J.S.; Lee, J.H.; Kim, C.O.; Hong, J.P.; Han, S.K.; Char, K.

    2002-01-01

    Highly selective high-temperature superconducting band-pass filters based on spiral meander line structures have been developed for base transceiver station applications of digital cellular communication systems. The filter comprised 12-pole microstrip line resonators with a circuit size of 0.5x17x41 mm 3 . The filter was designed to have a bandwidth of 25 MHz at a centre frequency of 834 MHz. Particularly, the physical size of each resonator was chosen not only to reduce far-field radiation, but also to have reasonable tunability in the filter. Device characteristics exhibited a low insertion loss of 0.4 dB with a 0.2 dB ripple and a return loss better than 10 dB in the pass-band at 65 K. The out-of-band signals were attenuated better than 60 dB at about 3.5 MHz from the lower band edge, and 3.8 MHz from the higher band edge. (author)

  3. Digital multilayer tomography

    International Nuclear Information System (INIS)

    Dueber, C.; Klose, K.J.; Thelen, M.

    1991-01-01

    With digital multilayer tomography a sequence of projection images is recorded by an image intensifier television system and stored as digital data during a linear run of a layer sequence. Using this data record, tomograms of the examined body region can be computed for any layer thickness by shifts and superimposition of the single projections later at a digital workstation. The qualities of digital and conventional tomograms are basically comparable. A drawback of digital tomography is its lower local resolution (512 x 512 image matrix), advantages are a lower radiation exposure, a shorter patient examination time, and the facilities of digital image processing (later processing, archive setup, transmission). (orig.) [de

  4. Experience with digital mammography

    Directory of Open Access Journals (Sweden)

    G. P. Korzhenkova

    2011-01-01

    Full Text Available The use of digital techniques in mammography has become a last step for completing the process of digitization in diagnostic imaging. It is assumed that such a spatial decision will be required for digital mammography, as well as for high-resolution intensifying screen-film systems used in conventional mammography and that the digital techniques will be limited by the digitizer pixel size on detecting minor structures, such as microcalcifications. The introduction of digital technologies in mammography involves a tight control over an image and assures its high quality.

  5. Logic of the digital

    CERN Document Server

    Evens, Aden

    2015-01-01

    Building a foundational understanding of the digital, Logic of the Digital reveals a unique digital ontology. Beginning from formal and technical characteristics, especially the binary code at the core of all digital technologies, Aden Evens traces the pathways along which the digital domain of abstract logic encounters the material, human world. How does a code using only 0s and 1s give rise to the vast range of applications and information that constitutes a great and growing portion of our world? Evens' analysis shows how any encounter between the actual and the digital must cross an ontolo

  6. Chaotic signals in digital communications

    CERN Document Server

    Eisencraft, Marcio; Suyama, Ricardo

    2013-01-01

    Chaotic Signals in Digital Communications combines fundamental background knowledge with state-of-the-art methods for using chaotic signals and systems in digital communications. The book builds a bridge between theoretical works and practical implementation to help researchers attain consistent performance in realistic environments. It shows the possible shortcomings of the chaos-based communication systems proposed in the literature, particularly when they are subjected to non-ideal conditions. It also presents a toolbox of techniques for researchers working to actually implement such system

  7. Materials Testing - Digital Ecology

    Directory of Open Access Journals (Sweden)

    Seth Wiley

    2013-03-01

    Full Text Available Access to credible building product performance information throughout the design and construction process is critical to enable project development, vet product selections, ensure as-built quality, and successfully complete construction. This is common knowledge and part of common practice for nearly all parties involved in design and construction. The sources of such information can range from vernacular to formal – from common practice to special reference. The focus of this paper is one of the more formal or specialized information sources, performance testing, as well as how such performance testing information can be better used. This paper’s goals are to familiarize the reader with performance testing and to depict a new kind of valuable informational tool (digital ecology. Reference to pertinent nomenclature, description of a real world example, and detailed description of such an informational tool’s values will be provided.The major content of this paper was developed during project-based work and firm-funded internal research at point b design, ltd. over approximately the previous 4 years. The phrase ‘digital ecology’ as herein used is a new concept proposed by the author. The analysis contained in this paper could be applied to the field of operations and maintenance as it is herein applied to design and construction; however, operations and maintenance is beyond the scope of this paper and may be addressed in future papers. It is my hope that this paper will contribute to tangible and real improvements of the built environment via continued, positive development within academic and professional practice.

  8. Digital angiography in pulmonary embolism

    International Nuclear Information System (INIS)

    Bjoerk, L.

    1986-01-01

    Pulmonary digital subtraction angiography was diagnostic in 98.3% of patients with possible acute pulmonary embolism. The procedure was well tolerated even in severely ill patients. A large image intensifier made simultaneous imaging of both lungs possible reducing the number of contrast injections necessary. Small volumes of low iso-osmolar concentration of modern contrast media were used. There was no need for catherization of the pulmonary artery. Theoretical considerations and our limited experience indicate that this will reduce the number of complications compared with conventional pulmonary angiography. The procedure is rapidly performed and the diagnostic accuracy high. This makes digital subtraction angiography cost effective. Digital pulmonary angiography can be recommended as the primary diagnostic method in most patients with possible pulmonary embolism. (orig.)

  9. Math for the digital factory

    CERN Document Server

    Hömberg, Dietmar; Landry, Chantal

    2017-01-01

    This volume provides a unique collection of mathematical tools and industrial case studies in digital manufacturing. It addresses various topics, ranging from models of single production technologies, production lines, logistics and workflows to models and optimization strategies for energy consumption in production. The digital factory represents a network of digital models and simulation and 3D visualization methods for the holistic planning, realization, control and ongoing improvement of all factory processes related to a specific product. In the past ten years, all industrialized countries have launched initiatives to realize this vision, sometimes also referred to as Industry 4.0 (in Europe) or Smart Manufacturing (in the United States). Its main goals are • reconfigurable, adaptive and evolving factories capable of small-scale production • high-performance production, combining flexibility, productivity, precision and zero defects • energy and resource efficiency in manufacturing None of these...

  10. Digital Literacy Instruction for eHealth and Beyond

    Science.gov (United States)

    Hill, Laura

    2016-01-01

    The increasing importance of digital technologies can disenfranchise individuals who lack digital literacy skills. As clinics adopt online health portals, even health care services require digital skills. Patients are often expected to check test results and perform other health-related tasks online, but few clinics provide support for those who…

  11. Challenges of Digital Preservation for Cultural Heritage Institutions

    Science.gov (United States)

    Evens, Tom; Hauttekeete, Laurence

    2011-01-01

    This article elaborates four major issues hampering the sustainability of digital preservation within cultural heritage institutions: digitization, metadata indexes, intellectual property rights management and business models. Using a case-study approach, the digitization of audiovisual collections within the performing arts institutions in…

  12. 37 CFR 255.4 - Definition of digital phonorecord delivery.

    Science.gov (United States)

    2010-07-01

    ... phonorecord delivery. 255.4 Section 255.4 Patents, Trademarks, and Copyrights COPYRIGHT OFFICE, LIBRARY OF... delivery. A “digital phonorecord delivery” is each individual delivery of a phonorecord by digital... time or for a specified number of performances. A digital phonorecord delivery includes all...

  13. Coastal California Digital Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the digital...

  14. Digital rectal exam

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007069.htm Digital rectal exam To use the sharing features on this page, please enable JavaScript. A digital rectal exam is an examination of the lower ...

  15. Digital Modeling Phenomenon Of Surface Ground Movement

    Directory of Open Access Journals (Sweden)

    Ioan Voina

    2016-11-01

    Full Text Available With the development of specialized software applications it was possible to approach and resolve complex problems concerning automating and process optimization for which are being used field data. Computerized representation of the shape and dimensions of the Earth requires a detailed mathematical modeling, known as "digital terrain model". The paper aims to present the digital terrain model of Vulcan mining, Hunedoara County, Romania. Modeling consists of a set of mathematical equations that define in detail the surface of Earth and has an approximate surface rigorously and mathematical, that calculated the land area. Therefore, the digital terrain model means a digital representation of the earth's surface through a mathematical model that approximates the land surface modeling, which can be used in various civil and industrial applications in. To achieve the digital terrain model of data recorded using linear and nonlinear interpolation method based on point survey which highlights the natural surface studied. Given the complexity of this work it is absolutely necessary to know in detail of all topographic elements of work area, without the actions to be undertaken to project and manipulate would not be possible. To achieve digital terrain model, within a specialized software were set appropriate parameters required to achieve this case study. After performing all steps we obtained digital terrain model of Vulcan Mine. Digital terrain model is the complex product, which has characteristics that are equivalent to the specialists that use satellite images and information stored in a digital model, this is easier to use.

  16. Superconductor Digital-RF Receiver Systems

    Science.gov (United States)

    Mukhanov, Oleg A.; Kirichenko, Dmitri; Vernik, Igor V.; Filippov, Timur V.; Kirichenko, Alexander; Webber, Robert; Dotsenko, Vladimir; Talalaevskii, Andrei; Tang, Jia Cao; Sahu, Anubhav; Shevchenko, Pavel; Miller, Robert; Kaplan, Steven B.; Sarwana, Saad; Gupta, Deepnarayan

    Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ˜30GHz clock frequencies.

  17. Digital Multi Channel Analyzer Enhancement

    International Nuclear Information System (INIS)

    Gonen, E.; Marcus, E.; Wengrowicz, U.; Beck, A.; Nir, J.; Sheinfeld, M.; Broide, A.; Tirosh, D.

    2002-01-01

    A cement analyzing system based on radiation spectroscopy had been developed [1], using novel digital approach for real-time, high-throughput and low-cost Multi Channel Analyzer. The performance of the developed system had a severe problem: the resulted spectrum suffered from lack of smoothness, it was very noisy and full of spikes and surges, therefore it was impossible to use this spectrum for analyzing the cement substance. This paper describes the work carried out to improve the system performance

  18. Digital dannelse til gymnasieeleverne

    DEFF Research Database (Denmark)

    Kaarsted, Thomas; Holch Andersen, Knud

    2012-01-01

    Søsætningen af en ny tænketank skal udstikke nye digital retningslinjer for gymnasiekolerne. Baggrunden er en erkendelse af, at it-infrastruktur og digital teknologi ikke gør de alene.......Søsætningen af en ny tænketank skal udstikke nye digital retningslinjer for gymnasiekolerne. Baggrunden er en erkendelse af, at it-infrastruktur og digital teknologi ikke gør de alene....

  19. Basic digital signal processing

    CERN Document Server

    Lockhart, Gordon B

    1985-01-01

    Basic Digital Signal Processing describes the principles of digital signal processing and experiments with BASIC programs involving the fast Fourier theorem (FFT). The book reviews the fundamentals of the BASIC program, continuous and discrete time signals including analog signals, Fourier analysis, discrete Fourier transform, signal energy, power. The text also explains digital signal processing involving digital filters, linear time-variant systems, discrete time unit impulse, discrete-time convolution, and the alternative structure for second order infinite impulse response (IIR) sections.

  20. Digital asset management.

    Science.gov (United States)

    Humphrey, Clinton D; Tollefson, Travis T; Kriet, J David

    2010-05-01

    Facial plastic surgeons are accumulating massive digital image databases with the evolution of photodocumentation and widespread adoption of digital photography. Managing and maximizing the utility of these vast data repositories, or digital asset management (DAM), is a persistent challenge. Developing a DAM workflow that incorporates a file naming algorithm and metadata assignment will increase the utility of a surgeon's digital images. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Digital Inkjet Textile Printing

    OpenAIRE

    Wang, Meichun

    2017-01-01

    Digital inkjet textile printing is an emerging technology developed with the rise of the digital world. It offers a possibility to print high-resolution images with unlimited color selection on fabrics. Digital inkjet printing brings a revolutionary chance for the textile printing industry. The history of textile printing shows the law how new technology replaces the traditional way of printing. This indicates the future of digital inkjet textile printing is relatively positive. Differen...

  2. SU-G-TeP2-07: Dosimetric Characterization of a New HDR Multi-Channel Esophageal Applicator for Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, A; Gao, S; Greskovich, J; Wilkinson, D [Cleveland Clinic, Cleveland, OH (United States); Diener, T [Cleveland State University, Cleveland, OH (United States)

    2016-06-15

    Purpose: To characterize the dose distribution of a new multi-channel esophageal applicator for brachytherapy HDR treatment, and particularly the effect of the presence of air or water in the applicator’s expansion balloon. Methods: A new multi-channel (6) inflatable applicator for esophageal HDR has been developed in house and tested in a simple water phantom. CT image sets were obtained under several balloon expansions (80ml of air, 50 cc of water), and channel loadings and used with the Oncentra (Elekta) planning system based on TG43 formalism. 400 cGy was prescribed to a plane 1cm away from the applicator. Planar dose distributions were measured for that plane and one next to the applicator using Gafchromic EBT3 film and scanned by a Vidar VXR-12 film digitizer. Film and TPS generated dose distributions of film were sent to OmniPro I’mRT (iba DOSIMETRY) for analysis. 2D dose profiles in both X and Y directions were compared and gamma analysis performed. Results: Film dose measurement of the air-inflated applicator is lower than the TPS calculated dose by as much as 60%. Only 80.8% of the pixels passed the gamma criteria (3%/3mm). For the water-inflated applicator, the measured film dose is fairly close to the TPS calculated dose (typically within <3%). 99.84% of the pixels passed the gamma criteria (3%/3mm). Conclusion: TG43 based calculations worked well when water was used in the expansion balloon. However, when air is present in that balloon, the neglect of heterogeneity corrections in the TG43 calculation results in large differences between calculated and measured doses. This could result in severe underdosing when used in a patient. This study illustrates the need for a TPS with an advanced algorithm which can account for heterogeneity. Supported by Innovations Department, Cleveland Clinic.

  3. Digital reactivity meter

    International Nuclear Information System (INIS)

    Copie, M.; Valantic, B.

    1978-01-01

    Digital reactivity meters (DRM) are mostly used as measuring instruments, e.g. for calibration of control rods, and there are only a few cases of their incorporation into the control systems of the reactors. To move in this direction there is more development work needed. First of all, fast algorithms are needed for inverse kinetics equations to relieve the computer for more important tasks of reactor model solving in real time. The next problem, currently under investigation, is the incorporation of the reactor thermal-hydraulic model into the DRM so that it can be used in the power range. Such an extension of DHM allows presentation not only of the instantaneous reactivity of the system, but also the inserted reactivity can be estimated from the temperature reactivity feed-backs. One of the applications of this concept is the anomalous digital reactivity monitor (ADRN) as part of the reactor protection system. As a solution of the first problem, a fast algorithm for solving the inverse kinetics equations has been implemented in the off-line program RODCAL on CDC 1700 computer and tested for its accuracy by performing different control rod calibrations on the reactor TRIGA

  4. How to Forge a Digital Alibi on Mac OS X

    OpenAIRE

    Castiglione , Aniello; Cattaneo , Giuseppe; Prisco , Roberto ,; Santis , Alfredo ,; Yim , Kangbin

    2012-01-01

    Part 2: Workshop; International audience; Digital evidence is increasingly being used in court cases. It consists of traces left on digital devices from which one can infer information about the actions performed on those digital devices. Digital evidence can be on computers, phones, digital cameras belonging either to an alleged offender or to third parties, like servers operated by ISPs or by companies that offer web services, such as YouTube, Facebook and Gmail. Digital evidence can either...

  5. Digital Language Death

    Science.gov (United States)

    Kornai, András

    2013-01-01

    Of the approximately 7,000 languages spoken today, some 2,500 are generally considered endangered. Here we argue that this consensus figure vastly underestimates the danger of digital language death, in that less than 5% of all languages can still ascend to the digital realm. We present evidence of a massive die-off caused by the digital divide. PMID:24167559

  6. Digital language death.

    Directory of Open Access Journals (Sweden)

    András Kornai

    Full Text Available Of the approximately 7,000 languages spoken today, some 2,500 are generally considered endangered. Here we argue that this consensus figure vastly underestimates the danger of digital language death, in that less than 5% of all languages can still ascend to the digital realm. We present evidence of a massive die-off caused by the digital divide.

  7. Digital Imaging. Chapter 16

    Energy Technology Data Exchange (ETDEWEB)

    Clunie, D. [CoreLab Partners, Princeton (United States)

    2014-09-15

    The original means of recording X ray images was a photographic plate. Nowadays, all medical imaging modalities provide for digital acquisition, though globally, the use of radiographic film is still widespread. Many modalities are fundamentally digital in that they require image reconstruction from quantified digital signals, such as computed tomography (CT) and magnetic resonance imaging (MRI)

  8. Preparing collections for digitization

    CERN Document Server

    Bulow, Anna E

    2010-01-01

    Most libraries, archives and museums are confronting the challenges of providing digital access to their collections. This guide offers guidance covering the end-to-end process of digitizing collections, from selecting records for digitization to choosing suppliers and equipment and dealing with documents that present individual problems.

  9. Digital voltage discriminator

    International Nuclear Information System (INIS)

    Zhou Zhicheng

    1992-01-01

    A digital voltage discriminator is described, which is synthesized by digital comparator and ADC. The threshold is program controllable with high stability. Digital region of confusion is approximately equal to 1.5 LSB. This discriminator has a single channel analyzer function model with channel width of 1.5 LSB

  10. Playtesting the Digital Playground

    DEFF Research Database (Denmark)

    Majgaard, G.; Jessen, Carsten

    2009-01-01

    Being able to be absorbed in play in the digital playground is motivating for children who are used digital computer games. The children can play and exercise outdoors while using the same literacy as in indoor digital games. This paper presents a new playground product where an outdoor playgroun...

  11. A Harmonized Process Model for Digital Forensic Investigation Readiness

    OpenAIRE

    Valjarevic , Aleksandar; Venter , Hein

    2013-01-01

    Part 2: FORENSIC MODELS; International audience; Digital forensic readiness enables an organization to prepare itself to perform digital forensic investigations in an efficient and effective manner. The benefits include enhancing the admissibility of digital evidence, better utilization of resources and greater incident awareness. However, a harmonized process model for digital forensic readiness does not currently exist and, thus, there is a lack of effective and standardized implementations...

  12. Advantages and disadvantages of digital education

    OpenAIRE

    Mąkosa, Paweł

    2013-01-01

    The digitization of education in Poland is spreading into more and more areas. Therefore, it becomes necessary to analyse all its aspects, both advantages and disadvantages. In the performed reflection, an attempt to present the current state of the access to computers, the Internet and e-course books in Polish schools has been made. On the basis of the secondary analysis of various recent studies as well as own research performed, it has been determined that the level of digitization of educ...

  13. Digital disruption ?syndromes.

    Science.gov (United States)

    Sullivan, Clair; Staib, Andrew

    2017-05-18

    The digital transformation of hospitals in Australia is occurring rapidly in order to facilitate innovation and improve efficiency. Rapid transformation can cause temporary disruption of hospital workflows and staff as processes are adapted to the new digital workflows. The aim of this paper is to outline various types of digital disruption and some strategies for effective management. A large tertiary university hospital recently underwent a rapid, successful roll-out of an integrated electronic medical record (EMR). We observed this transformation and propose several digital disruption "syndromes" to assist with understanding and management during digital transformation: digital deceleration, digital transparency, digital hypervigilance, data discordance, digital churn and post-digital 'depression'. These 'syndromes' are defined and discussed in detail. Successful management of this temporary digital disruption is important to ensure a successful transition to a digital platform. What is known about this topic? Digital disruption is defined as the changes facilitated by digital technologies that occur at a pace and magnitude that disrupt established ways of value creation, social interactions, doing business and more generally our thinking. Increasing numbers of Australian hospitals are implementing digital solutions to replace traditional paper-based systems for patient care in order to create opportunities for improved care and efficiencies. Such large scale change has the potential to create transient disruption to workflows and staff. Managing this temporary disruption effectively is an important factor in the successful implementation of an EMR. What does this paper add? A large tertiary university hospital recently underwent a successful rapid roll-out of an integrated electronic medical record (EMR) to become Australia's largest digital hospital over a 3-week period. We observed and assisted with the management of several cultural, behavioural and

  14. Ageing and digital games

    DEFF Research Database (Denmark)

    Iversen, Sara Mosberg

    Digital games are still to a great degree considered a medium mainly for young boys. However, available statistics on Western media use show that this is far from the case. Increasingly, people of all ages and genders play digital games, also older adults in their early 60s and beyond. The aim...... of the book is to examine, analyse and discuss: 1) What older adults do with digital games and what meanings the use of digital games take on in the everyday life of older adults; 2) How older adults are perceived by society in relation to digital games; 3) How play and games can be used both...

  15. Digital positron annihilation spectrometer

    International Nuclear Information System (INIS)

    Cheng Bin; Weng Huimin; Han Rongdian; Ye Bangjiao

    2010-01-01

    With the high speed development of digital signal process, the technique of the digitization and processing of signals was applied in the domain of a broad class of nuclear technique. The development of digital positron lifetime spectrometer (DPLS) is more promising than the conventional positron lifetime spectrometer equipped with nuclear instrument modules. And digital lifetime spectrometer has many advantages, such as low noise, long term stability, flexible online or offline digital processing, simple setup, low expense, easy to setting, and more physical information. Digital constant fraction discrimination is for timing. And a new method of optimizing energy windows setting for digital positron lifetime spectrometer is also developed employing the simulated annealing for the convenient use. The time resolution is 220ps and the count rate is 200cps. (authors)

  16. PERFORMANCE

    Directory of Open Access Journals (Sweden)

    M Cilli

    2014-10-01

    Full Text Available This study aimed to investigate the kinematic and kinetic changes when resistance is applied in horizontal and vertical directions, produced by using different percentages of body weight, caused by jumping movements during a dynamic warm-up. The group of subjects consisted of 35 voluntary male athletes (19 basketball and 16 volleyball players; age: 23.4 ± 1.4 years, training experience: 9.6 ± 2.7 years; height: 177.2 ± 5.7 cm, body weight: 69.9 ± 6.9 kg studying Physical Education, who had a jump training background and who were training for 2 hours, on 4 days in a week. A dynamic warm-up protocol containing seven specific resistance movements with specific resistance corresponding to different percentages of body weight (2%, 4%, 6%, 8%, 10% was applied randomly on non consecutive days. Effects of different warm-up protocols were assessed by pre-/post- exercise changes in jump height in the countermovement jump (CMJ and the squat jump (SJ measured using a force platform and changes in hip and knee joint angles at the end of the eccentric phase measured using a video camera. A significant increase in jump height was observed in the dynamic resistance warm-up conducted with different percentages of body weight (p 0.05. In jump movements before and after the warm-up, while no significant difference between the vertical ground reaction forces applied by athletes was observed (p>0.05, in some cases of resistance, a significant reduction was observed in hip and knee joint angles (p<0.05. The dynamic resistance warm-up method was found to cause changes in the kinematics of jumping movements, as well as an increase in jump height values. As a result, dynamic warm-up exercises could be applicable in cases of resistance corresponding to 6-10% of body weight applied in horizontal and vertical directions in order to increase the jump performance acutely.

  17. Optical digital chaos cryptography

    Science.gov (United States)

    Arenas-Pingarrón, Álvaro; González-Marcos, Ana P.; Rivas-Moscoso, José M.; Martín-Pereda, José A.

    2007-10-01

    In this work we present a new way to mask the data in a one-user communication system when direct sequence - code division multiple access (DS-CDMA) techniques are used. The code is generated by a digital chaotic generator, originally proposed by us and previously reported for a chaos cryptographic system. It is demonstrated that if the user's data signal is encoded with a bipolar phase-shift keying (BPSK) technique, usual in DS-CDMA, it can be easily recovered from a time-frequency domain representation. To avoid this situation, a new system is presented in which a previous dispersive stage is applied to the data signal. A time-frequency domain analysis is performed, and the devices required at the transmitter and receiver end, both user-independent, are presented for the optical domain.

  18. Digital Student Expertise in the Making

    DEFF Research Database (Denmark)

    Stenbøg, Sofie

    student (e.g. Bennett et. al. 2008, Helsper & Eynon 2009). In this paper I go beyond the idea of digital expertise as something intrinsic. Building on STS’s central notion of performativity (e.g. Law & Singleton 2000) the paper argues that digital expertise should be studied as a temporary achievement......Digital Natives, iGens’ or New Millennium Learners (Prensky 2001, Raphelson 2014, OECD 2008). There are many labels for the generation of young (western) citizens who have grown up with digital, web based technologies as a crucial part of their everyday life. This genera-tion now inhabits schools...... all around the world and their entry has not escaped the attention from teachers, school managers and policy makers. A current trend within education management, in Denmark as well as internationally, is to incorporate the students’ digital skills or ‘expertise’ as a resource in teaching, e.g. through...

  19. Intraoperative digital angiography: Peripheral vascular applications

    International Nuclear Information System (INIS)

    Bell, K.; Reifsteck, J.E.; Binet, E.F.; Fleisher, H.J.

    1986-01-01

    Intraoperative digital angiography is the procedure of choice for the peripheral vascular surgeon who wishes to evaluate his results before terminating anesthesia. Two operating suites at the John L. McClellan Memorial Veterans Hospital are equipped with permanent ceiling-mounted Philips C-arm fluoroscopes and share an ADAC 4100 digital angiographic system. In the last 18 months, 40 peripheral vascular intraoperative digital angiographic procedures have been performed, in all but two cases using direct arterial puncture. In 65% of cases, the intraoperative study showed no significant abnormality. In 12.5%, minor abnormalities not requiring reoperation were seen. In 22.5% of cases, the intraoperative digital angiogram revealed a significant abnormality requiring immediate operative revision. None of the patients who underwent reoperation experienced postoperative sequelae. Intraoperative digital angiography is useful in identifying complications of peripheral vascular operations

  20. Digital front-end module (DFEM) series; Digital front end module (DFEM) series

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The digital front-end module (DFEM) is a module in which the processes ranging from the reception of digitally modulated radiofrequencies to the output of digital IF (Intermediate Frequency) signals or data streams are integrated. Beginning with a module for the MCNS (Multimedia Cable Network System) cable modem which was the first module in this business field approved by the Cable Labs, U.S., Toshiba has developed a series of DFEMs for various digital media for satellites, ground waves, and CATV (Cable Television) systems. The series is characterized by (1) the serialization of DFEMs compatible with various digital modulation techniques such as 8 PSK (Phase Shift Keying), OFDM (Orthogonal Frequency Division Multiplexing), and 256 QAM (Quadrature Amplitude Modulation), (2) easy connection with digital circuits thanks to the high shielding effect, and (3) the achievement of smaller size, higher performance, and lower power consumption. (translated by NEDO)

  1. Digitally assisted pipeline ADCs theory and implementation

    CERN Document Server

    Murmann, Boris

    2007-01-01

    List of Figures. List of Tables. Acknowledgements. Preface. 1: Introduction. 1. Motivation. 2. Overview. 3. Chapter Organization. 2: Performance Trends. 1. Introduction. 2. Digital Performance Trends. 3. ADC Performance Trends. 3: Scaling Analysis. 1. Introduction. 2. Basic Device Scaling from a Digital Perspective. 3. Technology Metrics for Analog Circuits. 4. Scaling Impact on Matching-Limited Circuits. 5. Scaling Impact on Noise-Limited Circuits. 4: Improving Analog Circuit Efficiency. 1. Introduction. 2. Analog Circuit Challenges. 3. The Cost of Feedback. 4. Two-Stage Feedback Amplifier vs. Open-Loop Gain Stage. 5. Discussion. 5: Open-Loop Pipelined ADCs. 1. A Brief Review of Pipelined ADCs. 2. Conventional Stage Implementation. 3. Open-Loop Pipeline Stages. 4. Alternative Transconductor Implementations. 6: Digital Nonlinearity Correction. 1. Overview. 2. Error Model and Digital Correction. 3. Alternative Error Models. 7: Statistics-Based Parameter Estimation. 1. Introduction. 2. Modulation Approach. 3. R...

  2. Perspectives on Language Sustainability in a Performance Era: Discourses, Policies, and Practices in a Digital and Social Media Campaign to Revitalise Irish

    Directory of Open Access Journals (Sweden)

    Kelly-Holmes Helen

    2017-08-01

    Full Text Available The poststructuralist turn has been widely acknowledged in contemporary applied and sociolinguistics (Rampton 2006, Blommaert 2010. While for many this paradigmatic shift has been a welcome challenge to segregationalist approaches (Mühlhäusler 1996, Makoni and Pennycook 2007 and deficit discourses in relation to multilingualism (Jacquemet 2005, Jaffe 2007, it is not an unproblematic concept for minority language media and language sustainability. For those committed to activism and engagement with policy makers, the current paradigmatic shift, which has been described in terms of a performance era for minority language media (Pietikäinen and Kelly-Holmes 2011, presents particular challenges which have the potential to undermine gains made in previous eras in relation to media rights for minority language speakers. Using the example of a recent multi-media campaign to revitalise Irish, the Bród Club, this paper explores the opportunities and problems presented by the contemporary performance era for minority language media.

  3. Digital Banking: Risks of Financial Digitalization

    Directory of Open Access Journals (Sweden)

    Kornіvska Valerіa O.

    2017-09-01

    Full Text Available The paper demonstrates the results of the research into development of the digital economy in the global financial space, shows the contradictions of these processes in the context of the growth of financial inclusion of households, identifies the risks of active introduction of digital banking in poor countries of the world. The characteristics of the processes of growth of the influence of banking institutions on the operational activity and daily life of households are given, and it is proved that under conditions of digital banking, without having any other alternative ways of economic activity in terms of money circulation than non-cash turnover, clients are forced to agree to unlimited presence of financial operators in social systems. It is substantiated that in Ukraine the global risk of digitalization of the society is gradually developing as a result of the creation of unified information systems for the control of global financial flows.

  4. Digital rights management for digital cinema

    Science.gov (United States)

    Kirovski, Darko; Peinado, Marcus; Petitcolas, Fabien A. P.

    2001-12-01

    There is a wide consensus among the feature film production studios that the Internet era brings a new paradigm for film distribution to cinemas worldwide. The benefits of digital cinema to both producers and cinemas are numerous: significantly lower distribution and maintenance costs, immediate access to film libraries, higher presentation quality, and strong potential for developing new business models. Despite these advantages, the studios are still reluctant to jump into the digital age. The main showstopper for digital cinema is the danger of widespread piracy. Piracy already costs Hollywood an estimated two billion dollars annually and digital cinema without proper copyright enforcement could increase this number. In this paper, we present a copyright management system that aims at providing the set of necessary security tools: standard cryptographic primitives and copyright protection mechanisms that enable a reliable and secure feature film delivery system.

  5. Digital Collections, Digital Libraries and the Digitization of Cultural Heritage Information.

    Science.gov (United States)

    Lynch, Clifford

    2002-01-01

    Discusses the development of digital collections and digital libraries. Topics include digitization of cultural heritage information; broadband issues; lack of compelling content; training issues; types of materials being digitized; sustainability; digital preservation; infrastructure; digital images; data mining; and future possibilities for…

  6. Integration technique of digital I and C replacement and its Critical Digital Review procedure

    International Nuclear Information System (INIS)

    Huang, Hui-Wen; Yang, Wen-Long

    2013-01-01

    Highlights: ► A digital I and C replacement integration technique have been developed. ► Establishment of Nuclear Power Plant Digital Replacement Integration Guideline. ► Preliminary Investigation on I and C System Digitalization. ► Evaluation on I and C System Digitalization. ► Establishment of I and C System Digitalization Architectures. -- Abstract: Institute of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin–Shan (CS) NPP, Kuo–Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) procedure. The digital I and C replacement integration technique includes: (1) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR-1011710 (2005) “Handbook for Evaluating Critical Digital Equipment and Systems” which was published by the Electric Power Research Institute (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SV and V), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of

  7. Users' performance in lab and non-lab environments through online usability testing:A case of evaluating the usability of digital academic libraries' websites

    OpenAIRE

    Alharbi, Abeer; Mayhew, Pam

    2015-01-01

    The factors related to the environment in which users operate may be of a vital importance when trying to understand how they experience a particular system. It is required that we find out how we can get to know those factors to investigate if they affect the users' performance in usability testing. An online usability study has emerged that can be attempted by a large, varied pool of users' anywhere with an Internet connection. Would the usage of an online usability study help to give compr...

  8. The Profiles in Science Digital Library: Behind the Scenes.

    Science.gov (United States)

    Gallagher, Marie E; Moffatt, Christie

    2012-01-01

    This demonstration shows the Profiles in Science ® digital library. Profiles in Science contains digitized selections from the personal manuscript collections of prominent biomedical researchers, medical practitioners, and those fostering science and health. The Profiles in Science Web site is the delivery mechanism for content derived from the digital library system. The system is designed according to our basic principles for digital library development [1]. The digital library includes the rules and software used for digitizing items, creating and editing database records and performing quality control as well as serving the digital content to the public. Among the types of data managed by the digital library are detailed item-level, collection-level and cross-collection metadata, digitized photographs, papers, audio clips, movies, born-digital electronic files, optical character recognized (OCR) text, and annotations (see Figure 1). The digital library also tracks the status of each item, including digitization quality, sensitivity of content, and copyright. Only items satisfying all required criteria are released to the public through the World Wide Web. External factors have influenced all aspects of the digital library's infrastructure.

  9. Successful replantation in ten-digit amputation.

    Science.gov (United States)

    Kantarci, Umit; Cepel, Selim; Buldu, Halil

    2010-01-01

    Amputations involving ten digits are very rare because of different lengths of the digits. A 34-year-old man working in a printing house presented one hour after guillotine amputation involving all ten digits. Surgery was initiated 80 minutes after admission and took seven hours. Under axillary anesthesia, the operation was performed by two teams each consisting of two microsurgeons and two assistants. Replantation was completed without the use of any skin graft or flap. Fingertip examination showed poor arterial circulation in the second, third, and fourth digits of the left hand after 24 hours of replantation and surgical exploration was performed, during which anastomosis of the ulnar digital artery of the second digit was re-established and a Y-shaped vein graft was placed at the level of the third web to restore revascularization of the third and fourth digits. However, these interventions did not prevent the development of necrosis in the distal segment of the fourth digit which resulted in dry gangrene that required amputation. After 38 months of replantation, radiographic examination showed complete union in all fingers without malunion or damage to the joint surface and about 8 degrees of medial angulation in the proximal phalanx of the fourth digit of the right hand. The patient did not have difficulty in performing daily activities and had a considerably good pinching. Losses of active range of motion of the metacarpophalangeal and interphalangeal joints were within the rage of 10 to 30 degrees in both hands. In the assessment of sensation, static and dynamic two-point discrimination test results were 6.1 mm and 4.0 mm, respectively.

  10. Engaging Digital Natives through Social Learning

    Directory of Open Access Journals (Sweden)

    Nina Sarkar

    2017-04-01

    Full Text Available Digital natives account for a substantial portion of the total enrollment in higher education. This calls for significant educational reforms because traditional education systems do not cater to the needs and interests of digital natives. The most effective way that both students and instructors can benefit from this paradigm shift is to integrate technology that is appropriate to the cognitive learning patterns of the digital natives into the curriculum. This paper builds upon previous research in technology/personality theory and specifically attempts to provide examples of technology that will address the instructional needs of digital natives. Further this paper provides empirical evidence of the impact of technology integration on the learning outcomes of digital natives. In this study, the authors explored the impact of targeted technology on academic performance in three businesses courses. Three functional technologies were used by the authors to build engaging course content, efficiently manage course content, and to interact with digital native students. This study found that these technologies can assist digital natives in the learning process and lead to better academic performance.

  11. Digital vs. conventional implant impressions: efficiency outcomes.

    Science.gov (United States)

    Lee, Sang J; Gallucci, German O

    2013-01-01

    The aim of this pilot study was to evaluate the efficiency, difficulty and operator's preference of a digital impression compared with a conventional impression for single implant restorations. Thirty HSDM second year dental students performed conventional and digital implant impressions on a customized model presenting a single implant. The outcome of the impressions was evaluated under an acceptance criteria and the need for retake/rescan was decided. The efficiency of both impression techniques was evaluated by measuring the preparation, working, and retake/scan time (m/s) and the number of retakes/rescans. Participants' perception on the level of difficulty for the both impressions was assessed with a visual analogue scale (VAS) questionnaire. Multiple questionnaires were obtained to assess the participants' perception on preference, effectiveness and proficiency. Mean total treatment time was of 24:42 m/s for conventional and 12:29 m/s for digital impressions (P impressions (P impression (P impression technique and 30.63 (±17.57) for digital impression technique (P = 0.006). Sixty percent of the participants preferred the digital impression, 7% the conventional impression technique and 33% preferred either technique. Digital impressions resulted in a more efficient technique than conventional impressions. Longer preparation, working, and retake time were consumed to complete an acceptable conventional impression. Difficulty was lower for the digital impression compared with the conventional ones when performed by inexperienced second year dental students. © 2012 John Wiley & Sons A/S.

  12. Digital Architecture Planning Model

    International Nuclear Information System (INIS)

    Oxstrand, Johanna Helene; Al Rashdan, Ahmad Yahya Mohammad; Bly, Aaron Douglas; Rice, Brandon Charles; Fitzgerald, Kirk; Wilson, Keith Leon

    2016-01-01

    As part of the U.S. Department of Energy's Light Water Reactor Sustainability Program, the Digital Architecture (DA) Project focuses on providing a model that nuclear utilities can refer to when planning deployment of advanced technologies. The digital architecture planning model (DAPM) is the methodology for mapping power plant operational and support activities into a DA that unifies all data sources needed by the utilities to operate their plants. The DA is defined as a collection of information technology capabilities needed to support and integrate a wide spectrum of real-time digital capabilities for performance improvements of nuclear power plants. DA can be thought of as integration of the separate instrumentation and control and information systems already in place in nuclear power plants, which are brought together for the purpose of creating new levels of automation in plant work activities. A major objective in DAPM development was to survey all key areas that needed to be reviewed in order for a utility to make knowledgeable decisions regarding needs and plans to implement a DA at the plant. The development was done in two steps. First, researchers surveyed the nuclear industry in order to learn their near-term plans for adopting new advanced capabilities and implementing a network (i.e., wireless and wire) infrastructure throughout the plant, including the power block. Secondly, a literature review covering regulatory documents, industry standards, and technical research reports and articles was conducted. The objective of the review was to identify key areas to be covered by the DAPM, which included the following: 1. The need for a DA and its benefits to the plant 2. Resources required to implement the DA 3. Challenges that need to be addressed and resolved to implement the DA 4. Roles and responsibilities of the DA implementation plan. The DAPM was developed based on results from the survey and the literature review. Model development

  13. Digital Architecture Planning Model

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna Helene [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Al Rashdan, Ahmad Yahya Mohammad [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Bly, Aaron Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Rice, Brandon Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Wilson, Keith Leon [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS)

    2016-03-01

    As part of the U.S. Department of Energy’s Light Water Reactor Sustainability Program, the Digital Architecture (DA) Project focuses on providing a model that nuclear utilities can refer to when planning deployment of advanced technologies. The digital architecture planning model (DAPM) is the methodology for mapping power plant operational and support activities into a DA that unifies all data sources needed by the utilities to operate their plants. The DA is defined as a collection of information technology capabilities needed to support and integrate a wide spectrum of real-time digital capabilities for performance improvements of nuclear power plants. DA can be thought of as integration of the separate instrumentation and control and information systems already in place in nuclear power plants, which are brought together for the purpose of creating new levels of automation in plant work activities. A major objective in DAPM development was to survey all key areas that needed to be reviewed in order for a utility to make knowledgeable decisions regarding needs and plans to implement a DA at the plant. The development was done in two steps. First, researchers surveyed the nuclear industry in order to learn their near-term plans for adopting new advanced capabilities and implementing a network (i.e., wireless and wire) infrastructure throughout the plant, including the power block. Secondly, a literature review covering regulatory documents, industry standards, and technical research reports and articles was conducted. The objective of the review was to identify key areas to be covered by the DAPM, which included the following: 1. The need for a DA and its benefits to the plant 2. Resources required to implement the DA 3. Challenges that need to be addressed and resolved to implement the DA 4. Roles and responsibilities of the DA implementation plan. The DAPM was developed based on results from the survey and the literature review. Model development, including

  14. Digital Simulation in the Geosciences

    Directory of Open Access Journals (Sweden)

    Alexandr A. Lobanov

    2014-09-01

    Full Text Available This article provides an analysis of methods for digital modeling in the area of Earth Sciences. The author illustrates the difference between digital modeling in radio communication and that in the area of Earth Sciences. The article examines the integration aspect of digital models, demonstrates the advantages of digital over analog models, and illustrates that digital models are discrete. The author outlines the characteristics of digital modeling and illustrates the logical structure of digital models.

  15. A digital silicon photomultiplier with multiple time-to-digital converters

    Energy Technology Data Exchange (ETDEWEB)

    Garutti, Erika [University Hamburg (Germany); Silenzi, Alessandro [DESY, Hamburg (Germany); Xu, Chen [DESY, Hamburg (Germany); University Hamburg (Germany)

    2013-07-01

    A silicon photomultiplier (SiPM) with pixel level signal digitization and column-wise connected time-to-digital converters (TDCs) has been developed for an endoscopic Positron Emission Tomography (PET) detector. A digital SiPM has pixels consist of a single photon avalanche diode (SPAD) and circuit elements to optimize overall dark counts and temporal response. Compared with conventional analog SiPM, digital SiPM's direct signal route from SPAD to TDC improves single photon time resolution. In addition, using multiple TDCs can perform the statistical estimation of the time-of-arrival in multiple photon detection case such as readout of scintillation crystals. Characterization measurements of the prototype digital SiPM and a Monte-Carlo simulation to predict the timing performance of the PET detector are shown.

  16. Digital radiology and ultrasound

    International Nuclear Information System (INIS)

    Todd-Pokropek, A.

    1991-01-01

    With the access to digital methods for handling and processing images in general, many medical imaging methods are becoming more effectively handled digitally. This applies in particular to basically digital techniques such as CT and MR but also now includes Nuclear Medicine (NM), Ultrasound (US) and a variety of radiological procedures such as Digital Subtraction Angiography (DSA) and Fluoroscopy (DF). The access to conventional projection images by stimulatable plates (CR) or by digitization of film makes all of radiology potentially accessible, and the management of such images by a network is the basic aim of Picture Archiving and Communication Systems (PACS). However, it is suggested that in order for such systems to be of greater value, that way in which such images are treated needs to change, that is, digital images can be used to derive additional clinical value by appropriate processing

  17. Digital cine-imaging

    International Nuclear Information System (INIS)

    Masuda, Kazuhiro

    1992-01-01

    Digitization of fluoroscopic images has been developed for the digital cine imaging system as a result of the computer technology, television technology, and popularization of interventional radiology. Present digital cine imaging system is able to offer images similar to cine film because of the higher operatability and better image quality with the development of interventional radiology. As a result, its higher usefulness for catheter diagnosis examination except for interventional radiology was reported, and the possibility of having filmless cine is close to becoming a reality. However several problems have been pointed out, such as spatial resolution, time resolution, storage and exchangeability of data, disconsolidated viewing functions, etc. Anyhow, digital cine imaging system has some unresolved points and lots the needs to be discussed. The tendency of digitization is the passage of the time and we have to promote a study for more useful digital cine imaging system in team medical treatment which centers on the patients. (author)

  18. Theory of Digital Automata

    CERN Document Server

    Borowik, Bohdan; Lahno, Valery; Petrov, Oleksandr

    2013-01-01

    This book serves a dual purpose: firstly to combine the treatment of circuits and digital electronics, and secondly, to establish a strong connection with the contemporary world of digital systems. The need for this approach arises from the observation that introducing digital electronics through a course in traditional circuit analysis is fast becoming obsolete. Our world has gone digital. Automata theory helps with the design of digital circuits such as parts of computers, telephone systems and control systems. A complete perspective is emphasized, because even the most elegant computer architecture will not function without adequate supporting circuits. The focus is on explaining the real-world implementation of complete digital systems. In doing so, the reader is prepared to immediately begin design and implementation work. This work serves as a bridge to take readers from the theoretical world to the everyday design world where solutions must be complete to be successful.

  19. Professional Digital Compositing Essential Tools and Techniques

    CERN Document Server

    Lanier, Lee

    2009-01-01

    Learn professional secrets of digital compositing with this detailed guide. After filming is done, digital compositors move in to manipulate color, retouch, and perform other behind-the-scenes tricks that are necessary to improve or finalize movies, games, and commercials. Now you can learn their secrets with this one-of-a-kind guide to digital compositing. Professional animator and author Lee Lanier not only draws upon his own experience, he has also combed some of Hollywood's most active post-production houses in search of the best solutions. Learn valuable techniques, tricks, and more.: Cov

  20. Digital and analogue industrial radiography, application fields

    International Nuclear Information System (INIS)

    Willems, Peter; Millord, Erik Yardin

    2000-01-01

    Full text: Reusable phosphor screens for computer radiography (CR), amorphous selenium screens for direct radiography (DR), film digitalisation (FD) constitute imaging methods accepted by industry and are used for non-destructive radiographic testing (RT). Economic pressures are involving and affecting digital RT technology. Standards and codes for film radiography and radioscopy qualification do no longer cover the wide range of digital RT applications. It will be our task to optimise the performance of digital RT characterisation and to create appropriate examination methods to use all these new and existent technologies. In the meantime, an increasing automation and control of manual methods of analogue radiography can as well be expected. (author)

  1. Digital Maturity of the Firm's Business Model

    DEFF Research Database (Denmark)

    Groskovs, Sergejs; Vemula, Sreekanth

    We propose a digital maturity assessment model as an instrument for researchers and a strategic tool for managers. Existing literature lacks a conceptually clear way to measure the construct of digital maturity at the level of the firms business model. Our proposed instrument thus opens avenues...... for research into questions related to antecedents, process, and performance outcomes of the digitalization of business activities. The assessment follows the logic of first decomposing the business model into the underlying value creation activities and then evaluating the levels of automation...

  2. Digital image information systems in radiology

    International Nuclear Information System (INIS)

    Greinacher, C.F.C.; Luetke, B.; Seufert, G.

    1987-01-01

    About 25% of all patient examinations are performed digitally in a today's radiological department. A computerized system is described that supports generation, transport, interpretation and archiving of digital radiological images (Picture Archiving and Communication System PACS). The technical features concerning image communication via local area networks, image storage on magnetic and optical media and digital workstations for image display and manipulation are described. A structured system architecture is introduced. It allows flexible adaption to individual organizations and minimizes the requirements of the communication network. (orig.) [de

  3. Digital subtraction angiography for breast cancer

    International Nuclear Information System (INIS)

    Tsurumi, Kiyohiko; Okuyama, Nobuo

    1987-01-01

    We performed digital subtraction angiography (DSA) on 42 patients with breast diseases to investigate its efficiency. As a result we came to the following conclusions: 1. The sensitivity was well evaluated in intraarterial digital subtraction angiography (IA-DSA) of breast. 2. IA-DSA could diagnose difficult cases like cancer which had undergone augmentation mammoplasty, or like Paget's disease and others. 3. DSA was a safe examination method. 4. The sensitivity of IA-DSA of breast cancer is superior to intravenous digital subtraction angiography (IV-DSA). (author)

  4. 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.

  5. Digital collections and exhibits

    CERN Document Server

    Denzer, Juan

    2015-01-01

    Today's libraries are taking advantage of cutting-edge technologies such as flat panel displays using touch, sound, and hands-free motions to design amazing exhibits using everything from simple computer hardware to advanced technologies such as the Microsoft Kinect. Libraries of all types are striving to add new interactive experiences for their patrons through exciting digital exhibits, both online and off. Digital Collections and Exhibits takes away the mystery of designing stunning digital exhibits to spotlight library trea

  6. The digital computer

    CERN Document Server

    Parton, K C

    2014-01-01

    The Digital Computer focuses on the principles, methodologies, and applications of the digital computer. The publication takes a look at the basic concepts involved in using a digital computer, simple autocode examples, and examples of working advanced design programs. Discussions focus on transformer design synthesis program, machine design analysis program, solution of standard quadratic equations, harmonic analysis, elementary wage calculation, and scientific calculations. The manuscript then examines commercial and automatic programming, how computers work, and the components of a computer

  7. Digital Textile Printing

    OpenAIRE

    Moltchanova, Julia

    2011-01-01

    Rapidly evolving technology of digital printing opens new opportunities on many markets. One of them is the printed fabric market where printing companies as well as clients benefit from new printing methods. This thesis focuses on the digital textile printing technology and its implementation for fabric-on-demand printing service in Finland. The purpose of this project was to study the technology behind digital textile printing, areas of application of this technology, the requirements ...

  8. Digital Sensor Technology

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ken D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Quinn, Edward L. [Technology Resources, Dana Point, CA (United States); Mauck, Jerry L. [Technology Resources, Dana Point, CA (United States); Bockhorst, Richard M. [Technology Resources, Dana Point, CA (United States)

    2015-02-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy and reliability. This paper, which refers to a final report issued in 2013, demonstrates these benefits in direct comparisons of digital and analog sensor applications. Improved accuracy results from the superior operating characteristics of digital sensors. These include improvements in sensor accuracy and drift and other related parameters which reduce total loop uncertainty and thereby increase safety and operating margins. An example instrument loop uncertainty calculation for a pressure sensor application is presented to illustrate these improvements. This is a side-by-side comparison of the instrument loop uncertainty for both an analog and a digital sensor in the same pressure measurement application. Similarly, improved sensor reliability is illustrated with a sample calculation for determining the probability of failure on demand, an industry standard reliability measure. This looks at equivalent analog and digital temperature sensors to draw the comparison. The results confirm substantial reliability improvement with the digital sensor, due in large part to ability to continuously monitor the health of a digital sensor such that problems can be immediately identified and corrected. This greatly reduces the likelihood of a latent failure condition of the sensor at the time of a design basis event. Notwithstanding the benefits of digital sensors, there are certain qualification issues that are inherent with digital technology and these are described in the report. One major qualification impediment for digital sensor implementation is software common cause failure (SCCF).

  9. Preserving Digital Materials

    CERN Document Server

    Harvey, Ross

    2011-01-01

    This book provides a single-volume introduction to the principles, strategies and practices currently applied by librarians and recordkeeping professionals to the critical issue of preservation of digital information. It incorporates practice from both the recordkeeping and the library communities, taking stock of current knowledge about digital preservation and describing recent and current research, to provide a framework for reflecting on the issues that digital preservation raises in professional practice.

  10. Dakwah di Era Digital

    OpenAIRE

    Budiantoro, Wahyu

    2018-01-01

    These days dakwah is not only interpreted as transformation of a pure religious value, but also transformation of a more relevant value including many aspects in digital era. Digital era is when society succumbed into the flow of information causing cultural shock and difficulties on synthesizing meaning from those scattered information. Dakwah on Digital age must accommodate societal needs which tend to move into a mass society. It results in strategy and more humane and innovative dakwah me...

  11. The Digital Imperative

    OpenAIRE

    Veling, Louise; Murnane, Sinéad; Carcary, Marian; Zlydareva, Olga

    2014-01-01

    The pervasiveness of digital technologies and their potential for reshaping the industry landscape dictates that organizations operating today have little choice but to incorporate digital technologies into their business strategies. Failure to do so will impede the business’s viability, and may ultimately lead to business failure. However, for those organizations that successfully transition to digital business, unprecedented business opportunities exist for value creation and reali...

  12. Digital piracy : theory

    OpenAIRE

    BELLEFLAMME, Paul; PEITZ, Martin

    2010-01-01

    This article reviews recent theoretical contributions on digital piracy. It starts by elaborating on the reasons for intellectual property protection, by reporting a few facts about copyright protection, and by examining reasons to become a digital pirate. Next, it provides an exploration of the consequences of digital piracy, using a base model and several extensions (with consumer sampling, network effects, and indirect appropriation). A closer look at market-structure implications of end-u...

  13. La radio digital

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Cortés S.

    2015-01-01

    Full Text Available La radio digital es un producto de la llamada convergencia digital. Las nuevas tecnologías interconectadas permiten la aparición de nuevos modos de audiencia y la implementación de herramientas versátiles. Habla del problema de los estándares, de la radio satelital, la radio digital terrestre, las radios internacionales, la interactividad.

  14. Easy digital engineering

    International Nuclear Information System (INIS)

    Jin, Dal Bok

    2002-02-01

    This book lists basic of digital engineering, number system and digital code, Boolean algebra and basic logic circuit, simplify of logical expression, combinational circuit, arithmetic circuit, multivibrator circuit, sequential circuit, memory unit of semiconductor and logical element for program, D/A converter and A/D converter, logic element and integrated circuit and logic circuit and micro controller. It has exercises and answers about digital engineering and summary in the end of each chapter.

  15. Debunking the "Digital Native": Beyond Digital Apartheid, towards Digital Democracy

    Science.gov (United States)

    Brown, C.; Czerniewicz, L.

    2010-01-01

    This paper interrogates the currently pervasive discourse of the "net generation" finding the concept of the "digital native" especially problematic, both empirically and conceptually. We draw on a research project of South African higher education students' access to and use of Information and Communication Technologies (ICTs)…

  16. Digital Natives and Digital Divide: Analysing Perspective for Emerging Pedagogy

    Science.gov (United States)

    Onye, Uriel U.; Du, Yunfei

    2016-01-01

    This paper addresses the concepts of digital natives and digital divide from the perspective of the digital outsiders (part of digital natives). It takes a critical look at the implications of available ICT in both developed and underdeveloped countries in the fight against digital divide. The major contribution to literature is by drawing…

  17. Digital Recording and Non-Destructive Techniques for the Understanding of Structural Performance for Rehabilitating Historic Structures at the Kathmandu Valley after Gorkha Earthquake 2015

    Science.gov (United States)

    Shrestha, S.; Reina Ortiz, M.; Gutland, M.; Napolitano, R.; Morris, I. M.; Santana Quintero, M.; Erochko, J.; Kawan, S.; Shrestha, R. G.; Awal, P.; Suwal, S.; Duwal, S.; Maharjan, D. K.

    2017-08-01

    On 25 April 2015, the Gorkha earthquake of magnitude 7.8, severely damaged the cultural heritage sites of Nepal. In particular, the seven monument zones of the Kathmandu Valley World Heritage Site suffered extensive damage. Out of 195 surveyed monuments, 38 have completely collapsed and 157 partially damaged (DoA, 2015). In particular, the world historic city of Bhaktapur was heavily affected by the earthquake. There is, in general, a lack of knowledge regarding the traditional construction technology used in many of the most important temple monuments in Bhaktapur. To address this limitation and to assist in reconstruction and rehabilitation of the area, this study documents the existing condition of different historic structures in the Kathmandu Valley. In particular, the Nyatapola Temple is studied in detail. To record and document the condition of this temple, a combination of laser scanning and terrestrial and aerial photogrammetry are used. By also including evaluation of the temple and its supporting plinth structure using non-destructive evaluation techniques like geo-radar and micro-tremor dynamic analysis, this study will form the basis of a structural analysis study to assess the anticipated future seismic performance of the Nyatapola Temple.

  18. Digital subtraction angiography system evaluation with phantoms

    International Nuclear Information System (INIS)

    Wenstrup, R.S.; Sweeney, K.P.; Scholz, F.J.

    1985-01-01

    Advances in digital subtraction angiography imaging demonstrate the need for critical evaluation of the performance of digital subtraction equipment. The design of a phantom set for noninvasive assessment of the imaging quality of digital subtraction equipment is described; components include a remotely controlled transport system and individual patterns to evaluate the contrast and detail properties of the image intensifier, low-contrast sensitivity and resolution of the system, geometric distortion of image, linearity, mechanical and electronic stability of equipment, and effects of bone and bowel gas on iodine perception. The performance of an add-on digital radiographic system is presented, along with radiation exposure levels at the image intensifier for a range of radiographic techniques

  19. The digital media handbook

    CERN Document Server

    Dewdney, Andrew

    2013-01-01

    The new edition of The Digital Media Handbook presents an essential guide to the historical and theoretical development of digital media, emphasising cultural continuity alongside technological change, and highlighting the emergence of new forms of communication in contemporary networked culture.Andrew Dewdney and Peter Ride present detailed critical commentary and descriptive historical accounts, as well as a series of interviews from a range of digital media practitioners, including producers, developers, curators and artists.The Digital Media Handbook highlights key concerns of today's prac

  20. Digitization of conventional radiographs

    International Nuclear Information System (INIS)

    Wenz, W.; Buitrago-Tellez, C.; Blum, U.; Hauenstein, K.H.; Gufler, H.; Meyer, E.; Ruediger, K.

    1992-01-01

    The diagnostic value of a digitization system for analogue films based on a charge-coupled-device (CCD) scanner with adjustable resolution of 2.5 or 5 lp/mm was assessed. Some 110 skeletal radiographs, 50 contrast studies, including 25 of patients with Crohn's disease, and 70 abdominal plain films before and after successful lithotripsy for renal stones were digitized. Receiver operating characteristic (ROC) studies showed improved detection of cortical and trabecular defects with contrast-optimized digitized films. Edge enhancement algorithms yielded no additional information. Inflammatory lesions of Crohn's disease were detected equally well by conventional films and digitized images. A statistically significant improvement (p [de

  1. Digital security technology simplified.

    Science.gov (United States)

    Scaglione, Bernard J

    2007-01-01

    Digital security technology is making great strides in replacing analog and other traditional security systems including CCTV card access, personal identification and alarm monitoring applications. Like any new technology, the author says, it is important to understand its benefits and limitations before purchasing and installing, to ensure its proper operation and effectiveness. This article is a primer for security directors on how digital technology works. It provides an understanding of the key components which make up the foundation for digital security systems, focusing on three key aspects of the digital security world: the security network, IP cameras and IP recorders.

  2. Digitally-Driven Architecture

    Directory of Open Access Journals (Sweden)

    Henriette Bier

    2014-07-01

    Full Text Available The shift from mechanical to digital forces architects to reposition themselves: Architects generate digital information, which can be used not only in designing and fabricating building components but also in embedding behaviours into buildings. This implies that, similar to the way that industrial design and fabrication with its concepts of standardisation and serial production influenced modernist architecture, digital design and fabrication influences contemporary architecture. While standardisation focused on processes of rationalisation of form, mass-customisation as a new paradigm that replaces mass-production, addresses non-standard, complex, and flexible designs. Furthermore, knowledge about the designed object can be encoded in digital data pertaining not just to the geometry of a design but also to its physical or other behaviours within an environment. Digitally-driven architecture implies, therefore, not only digitally-designed and fabricated architecture, it also implies architecture – built form – that can be controlled, actuated, and animated by digital means.In this context, this sixth Footprint issue examines the influence of digital means as pragmatic and conceptual instruments for actuating architecture. The focus is not so much on computer-based systems for the development of architectural designs, but on architecture incorporating digital control, sens­ing, actuating, or other mechanisms that enable buildings to inter­act with their users and surroundings in real time in the real world through physical or sensory change and variation.

  3. Digitally-Driven Architecture

    Directory of Open Access Journals (Sweden)

    Henriette Bier

    2010-06-01

    Full Text Available The shift from mechanical to digital forces architects to reposition themselves: Architects generate digital information, which can be used not only in designing and fabricating building components but also in embedding behaviours into buildings. This implies that, similar to the way that industrial design and fabrication with its concepts of standardisation and serial production influenced modernist architecture, digital design and fabrication influences contemporary architecture. While standardisa­tion focused on processes of rationalisation of form, mass-customisation as a new paradigm that replaces mass-production, addresses non-standard, complex, and flexible designs. Furthermore, knowledge about the designed object can be encoded in digital data pertaining not just to the geometry of a design but also to its physical or other behaviours within an environment. Digitally-driven architecture implies, therefore, not only digitally-designed and fabricated architecture, it also implies architecture – built form – that can be controlled, actuated, and animated by digital means. In this context, this sixth Footprint issue examines the influence of digital means as prag­matic and conceptual instruments for actuating architecture. The focus is not so much on computer-based systems for the development of architectural designs, but on architecture incorporating digital control, sens­ing, actuating, or other mechanisms that enable buildings to inter­act with their users and surroundings in real time in the real world through physical or sensory change and variation.

  4. Exploring digital professionalism.

    Science.gov (United States)

    Ellaway, Rachel H; Coral, Janet; Topps, David; Topps, Maureen

    2015-01-01

    The widespread use of digital media (both computing devices and the services they access) has blurred the boundaries between our personal and professional lives. Contemporary students are the last to remember a time before the widespread use of the Internet and they will be the first to practice in a largely e-health environment. This article explores concepts of digital professionalism and their place in contemporary medical education, and proposes a series of principles of digital professionalism to guide teaching, learning and practice in the healthcare professions. Despite the many risks and fears surrounding their use, digital media are not an intrinsic threat to medical professionalism. Professionals should maintain the capacity for deliberate, ethical, and accountable practice when using digital media. The authors describe a digital professionalism framework structured around concepts of proficiency, reputation, and responsibility. Digital professionalism can be integrated into medical education using strategies based on awareness, alignment, assessment, and accountability. These principles of digital professionalism provide a way for medical students and medical practitioners to embrace the positive aspects of digital media use while being mindful and deliberate in its use to avoid or minimize any negative consequences.

  5. Radiographic film digitizing devices

    International Nuclear Information System (INIS)

    McFee, W.H.

    1988-01-01

    Until recently, all film digitizing devices for use with teleradiology or picture archiving and communication systems used a video camera to capture an image of the radiograph for subsequent digitization. The development of film digitizers that use a laser beam to scan the film represents a significant advancement in digital technology, resulting in improved image quality compared with video scanners. This paper discusses differences in resolution, efficiency, reliability, and the cost between these two types of devices. The results of a modified receiver operating characteristic comparison study of a video scanner and a laser scanner manufactured by the same company are also discussed

  6. Development of digital shade guides for color assessment using a digital camera with ring flashes.

    Science.gov (United States)

    Tung, Oi-Hong; Lai, Yu-Lin; Ho, Yi-Ching; Chou, I-Chiang; Lee, Shyh-Yuan

    2011-02-01

    Digital photographs taken with cameras and ring flashes are commonly used for dental documentation. We hypothesized that different illuminants and camera's white balance setups shall influence color rendering of digital images and affect the effectiveness of color matching using digital images. Fifteen ceramic disks of different shades were fabricated and photographed with a digital camera in both automatic white balance (AWB) and custom white balance (CWB) under either light-emitting diode (LED) or electronic ring flash. The Commission Internationale d'Éclairage L*a*b* parameters of the captured images were derived from Photoshop software and served as digital shade guides. We found significantly high correlation coefficients (r² > 0.96) between the respective spectrophotometer standards and those shade guides generated in CWB setups. Moreover, the accuracy of color matching of another set of ceramic disks using digital shade guides, which was verified by ten operators, improved from 67% in AWB to 93% in CWB under LED illuminants. Probably, because of the inconsistent performance of the flashlight and specular reflection, the digital images captured under electronic ring flash in both white balance setups revealed less reliable and relative low-matching ability. In conclusion, the reliability of color matching with digital images is much influenced by the illuminants and camera's white balance setups, while digital shade guides derived under LED illuminants with CWB demonstrate applicable potential in the fields of color assessments.

  7. Cognitive Hacking and Digital Government: Digital Identity

    Directory of Open Access Journals (Sweden)

    Paul Thompson

    2004-04-01

    Full Text Available Recently the National Center for Digital Government held a workshop on "The Virtual Citizen: Identity, Autonomy, and Accountability: A Civic Scenario Exploration of the Role of Identity in On-Line. Discussions at the workshop focused on five scenarios for future authentication policies with respect to digital identity. The underlying technologies considered for authentication were: biometrics: cryptography, with a focus on digital signatures; secure processing/computation; and reputation systems. Most discussion at the workshop focused on issues related to authentication of users of digital government, but, as implied by the inclusion of a scenario related to ubiquitous identity theft, there was also discussion of problems related to misinformation, including cognitive hacking. Cognitive hacking refers to a computer or information system attack that relies on changing human users' perceptions and corresponding behaviors in order to succeed. This paper describes cognitive hacking, suggests countermeasures, and discusses the implications of cognitive hacking for identity in digital government. In particular, spoofing of government websites and insider misuse are considered.

  8. INCORRECT PRESERVATION OF AMPUTATED DIGITS

    Directory of Open Access Journals (Sweden)

    Uroš Ahčan

    2004-09-01

    Full Text Available Background. A decision to replant is critically dependent on the condition of the amputated digit and the way it was preserved during transport. The most common error is exposing the amputated digit to very low temperatures. Preservation directly on ice, on cooling devices in portable refrigerators, or on top of packets of frozen meat often result in a frozen and therefore unusable body digit.Methods. An inquiry questionnaire on correct methods of preservation of amputated digits was conducted on a sample of 30 lay persons, 30 medical students, and 15 physicians.Three simulations of most frequently used methods of preservation of amputated digit were conducted (the correct method; directly on ice; on cooling devices of portable refrigerators. Environment temperature of the (simulated amputated digits stored was measured.In a retrospective study, hospital records of patients treated at the Clinical department of plastic surgery and burns in Ljubljana between 1998 and 2002 were examined. We determined the number of replantations performed, gender of the patients, their age, the mechanism of the injury, the success rate of the replantation, and the duration of hospitalisation. In five case described in detail, we present an inadequate treatment of the amputated digits.Results. The results of the questionnaire survey show that no less than 86.7% of lay person respondents would have treated the injuries in an incorrect way; same holds for 43.4% students of medicine, and 33.3% of practicing physicians.The temperature of the simulated amputated digit remained above 5°C throughout the simulated correct treatment. When preserved directly on ice on or coolant bodies, the temperature dropped below the freezing point and never climbed above 0°C throughout the duration of the simulation (150 minutes.Between years 1998 and 2002, Clinical department of plastic surgery and burns at the University clinical centre Ljubljana admitted 124 injured persons with

  9. Digital inductive teaching method of strabismus

    OpenAIRE

    Zhao-Jiang Du; Peng Li; Li Wang

    2015-01-01

    AIM: To reform the traditional teaching modes of strabismus by using digital induction to enhance logic in teaching process.METHODS: The study was performed in the group of 20 eight-year program clinical undergraduates from the class of 2009 and 198 five-year program clinical undergraduates from the class of 2010. These students were divided into two groups receiving traditional and digital induction teaching over the same period respectively. After classes, questionnaire survey and classroom...

  10. New techniques in digital holography

    CERN Document Server

    Picart, Pascal

    2015-01-01

    A state of the art presentation of important advances in the field of digital holography, detailing advances related to fundamentals of digital holography, in-line holography applied to fluid mechanics, digital color holography, digital holographic microscopy, infrared holography, special techniques in full field vibrometry and inverse problems in digital holography

  11. Performance evaluation of contrast-detail in full field digital mammography systems using ideal (Hotelling) observer vs. conventional automated analysis of CDMAM images for quality control of contrast-detail characteristics.

    Science.gov (United States)

    Delakis, Ioannis; Wise, Robert; Morris, Lauren; Kulama, Eugenia

    2015-11-01

    The purpose of this work was to evaluate the contrast-detail performance of full field digital mammography (FFDM) systems using ideal (Hotelling) observer Signal-to-Noise Ratio (SNR) methodology and ascertain whether it can be considered an alternative to the conventional, automated analysis of CDMAM phantom images. Five FFDM units currently used in the national breast screening programme were evaluated, which differed with respect to age, detector, Automatic Exposure Control (AEC) and target/filter combination. Contrast-detail performance was analysed using CDMAM and ideal observer SNR methodology. The ideal observer SNR was calculated for input signal originating from gold discs of varying thicknesses and diameters, and then used to estimate the threshold gold thickness for each diameter as per CDMAM analysis. The variability of both methods and the dependence of CDMAM analysis on phantom manufacturing discrepancies also investigated. Results from both CDMAM and ideal observer methodologies were informative differentiators of FFDM systems' contrast-detail performance, displaying comparable patterns with respect to the FFDM systems' type and age. CDMAM results suggested higher threshold gold thickness values compared with the ideal observer methodology, especially for small-diameter details, which can be attributed to the behaviour of the CDMAM phantom used in this study. In addition, ideal observer methodology results showed lower variability than CDMAM results. The Ideal observer SNR methodology can provide a useful metric of the FFDM systems' contrast detail characteristics and could be considered a surrogate for conventional, automated analysis of CDMAM images. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  12. Digital radiography and caries diagnosis.

    Science.gov (United States)

    Wenzel, A

    1998-01-01

    Direct digital acquisition of intra-oral radiographs has been possible only in the last decade. Several studies have shown that, theoretically, there are a number of advantages of direct digital radiography compared with conventional film. Laboratory as well as controlled clinical studies are needed to determine whether new digital imaging systems alter diagnosis, treatment and prognosis compared with conventional methods. Most studies so far have evaluated their diagnostic performance only in laboratory settings. This review concentrates on what evidence we have for the diagnostic efficacy of digital systems for caries detection. Digital systems are compared with film and those studies which have evaluated the effects on diagnostic accuracy of contrast and edge enhancement, image size, variations in radiation dose and image compression are reviewed together with the use of automated image analysis for caries diagnosis. Digital intra-oral radiographic systems seem to be as accurate as the currently available dental films for the detection of caries. Sensitivities are relatively high (0.6-0.8) for detection of occlusal lesions into dentine with false positive fractions of 5-10%. A radiolucency in dentine is recognised as a good predictor for demineralisation. Radiography is of no value for the detection of initial (enamel) occlusal lesions. For detection of approximal dentinal lesions, sensitivities, specificities as well as the predictive values are fair, but are very poor for lesions known to be confined to enamel. Very little documented information exists, however, on the utilization of digital systems in the clinic. It is not known whether dose is actually reduced with the storage phosphor system, or whether collimator size is adjusted to fit sensor size in the CCD-based systems. There is no evidence that the number of retakes have been reduced. It is not known how many images are needed with the various CCD systems when compared with a conventional bitewing

  13. Customizable Digital Receivers for Radar

    Science.gov (United States)

    Moller, Delwyn; Heavey, Brandon; Sadowy, Gregory

    2008-01-01

    Compact, highly customizable digital receivers are being developed for the system described in 'Radar Interferometer for Topographic Mapping of Glaciers and Ice Sheets' (NPO-43962), NASA Tech Briefs, Vol. 31, No. 7 (August 2007), page 72. The receivers are required to operate in unison, sampling radar returns received by the antenna elements in a digital beam-forming (DBF) mode. The design of these receivers could also be adapted to commercial radar systems. At the time of reporting the information for this article, there were no commercially available digital receivers capable of satisfying all of the operational requirements and compact enough to be mounted directly on the antenna elements. A provided figure depicts the overall system of which the digital receivers are parts. Each digital receiver includes an analog-to-digital converter (ADC), a demultiplexer (DMUX), and a field-programmable gate array (FPGA). The ADC effects 10-bit band-pass sampling of input signals having frequencies up to 3.5 GHz. The input samples are demultiplexed at a user-selectable rate of 1:2 or 1:4, then buffered in part of the FPGA that functions as a first-in/first-out (FIFO) memory. Another part of the FPGA serves as a controller for the ADC, DMUX, and FIFO memory and as an interface between (1) the rest of the receiver and (2) a front-panel data port (FPDP) bus, which is an industry-standard parallel data bus that has a high data-rate capability and multichannel configuration suitable for DBF. Still other parts of the FPGA in each receiver perform signal-processing functions. The digital receivers can be configured to operate in a stand-alone mode, or in a multichannel mode as needed for DBF. The customizability of the receiver makes it applicable to a broad range of system architectures. The capability for operation of receivers in either a stand-alone or a DBF mode enables the use of the receivers in an unprecedentedly wide variety of radar systems.

  14. Digital temperature meter

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, S

    1982-01-01

    Digital temperature meter for precise temperature measurements is presented. Its parts such as thermostat, voltage-frequency converter and digital frequency meter are described. Its technical parameters such as temperature range 50degC-700degC, measurement precision 1degC, measurement error +-1degC are given. (A.S.).

  15. Changing State Digital Libraries

    Science.gov (United States)

    Pappas, Marjorie L.

    2006-01-01

    Research has shown that state virtual or digital libraries are evolving into websites that are loaded with free resources, subscription databases, and instructional tools. In this article, the author explores these evolving libraries based on the following questions: (1) How user-friendly are the state digital libraries?; (2) How do state digital…

  16. Digital signage sobre IP

    OpenAIRE

    Casademont Filella, Albert

    2012-01-01

    Projecte que versa sobre el disseny i la implementació d'un sistema de Digital Signage (Cartelleria Digital) sobre IP, creant un gestor que permeti controlar de forma remota tot un conjunt de petits dispositius connectats a pantalles que emeten continguts multimèdia com vídeos, imatges, feeds rss...

  17. The First Digit 1

    Indian Academy of Sciences (India)

    IAS Admin

    1075. RESONANCE | December 2013. GENERAL | ARTICLE. Table 2. The first digits distri- bution according to Benford's law. First Frequency. Digit. 1. 30.1 %. 2. 17.6 %. 3. 12.4 %. 4. 9.7 %. 5. 7.9 %. 6. 6.7 %. 7. 5.8 %. 8. 5.1 %. 9. 4.5 % ...

  18. Digital Cultural Heritage

    NARCIS (Netherlands)

    Navarrete, T.; Rizzo, I.; Mignosa, A.

    2013-01-01

    What is the impact of media technology on the supply and demand of heritage with what is usually described as digitization? This chapter presents the concept of digitization as concerning far more than just the introduction of computers, the development of databases and websites, and the conversion

  19. Digital formidling af kulturarv

    DEFF Research Database (Denmark)

    En af tidens store kulturelle dagsordner drejer sig om digital tilgængeliggørelse af kulturarv. Fortidens spor dukker op i nye former på nettet - næsten alle kulturinstitutioner arbejder med, og befolkningen har fået helt nye muligheder for at se med og deltage. Digital formidling af kulturarv...

  20. Digitizing migration heritage

    DEFF Research Database (Denmark)

    Marselis, Randi

    2011-01-01

    Museums are increasingly digitizing their collections and making them available to the public on-line. Creating such digital resources may become means for social inclusion. For museums that acknowledge migration history and cultures of ethnic minority groups as important subjects in multiethnic...