WorldWideScience

Sample records for methods employing digital

  1. Improved non-invasive method for aerosol particle charge measurement employing in-line digital holography

    Science.gov (United States)

    Tripathi, Anjan Kumar

    Electrically charged particles are found in a wide range of applications ranging from electrostatic powder coating, mineral processing, and powder handling to rain-producing cloud formation in atmospheric turbulent flows. In turbulent flows, particle dynamics is influenced by the electric force due to particle charge generation. Quantifying particle charges in such systems will help in better predicting and controlling particle clustering, relative motion, collision, and growth. However, there is a lack of noninvasive techniques to measure particle charges. Recently, a non-invasive method for particle charge measurement using in-line Digital Holographic Particle Tracking Velocimetry (DHPTV) technique was developed in our lab, where charged particles to be measured were introduced to a uniform electric field, and their movement towards the oppositely charged electrode was deemed proportional to the amount of charge on the particles (Fan Yang, 2014 [1]). However, inherent speckle noise associated with reconstructed images was not adequately removed and therefore particle tracking data was contaminated. Furthermore, particle charge calculation based on particle deflection velocity neglected the particle drag force and rebound effect of the highly charged particles from the electrodes. We improved upon the existing particle charge measurement method by: 1) hologram post processing, 2) taking drag force into account in charge calculation, 3) considering rebound effect. The improved method was first fine-tuned through a calibration experiment. The complete method was then applied to two different experiments, namely conduction charging and enclosed fan-driven turbulence chamber, to measure particle charges. In all three experiments conducted, the particle charge was found to obey non-central t-location scale family of distribution. It was also noted that the charge distribution was insensitive to the change in voltage applied between the electrodes. The range of voltage

  2. 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

  3. Etching method employing radiation

    International Nuclear Information System (INIS)

    Chapman, B.N.; Winters, H.F.

    1982-01-01

    This invention provides a method for etching a silicon oxide, carbide, nitride, or oxynitride surface using an electron or ion beam in the presence of a xenon or krypton fluoride. No additional steps are required after exposure to radiation

  4. Employer Perceptions of Critical Information Literacy Skills and Digital Badges

    Science.gov (United States)

    Raish, Victoria; Rimland, Emily

    2016-01-01

    Digital badges are an educational innovation used to measure learning of specific skills, such as information literacy. However, few studies have quantitatively surveyed employers for their perceptions about information literacy skills or digital badges. An online survey was developed and sent to employers to gauge perceptions of information…

  5. Digital processing methods for bronchograms

    International Nuclear Information System (INIS)

    Mamilyaev, R.M.; Popova, N.P.; Matsulevich, T.V.

    1989-01-01

    The technique of digital processing of bronchograms with the aim of separating morphological details of bronchi and increasing the clarity in the outlines of contrasted bronchi, is described. The block diagram of digital processing on the automatized system of image processing is given. It is shown that digital processing of bronchograms permits to clearly outline bronchi walls and makes the measurements of bronchi diameters easier and more reliable. Considerable advantages of digital processing of images as compared with the optical methods, are shown

  6. Digital Storytelling and Employer Branding. An Exploratory Connection

    OpenAIRE

    Camelia CRIȘAN; Dumitru BORȚUN

    2017-01-01

    Our paper aims at explaining what is digital storytelling and its particular methodology, and how its use in the organizational settings could influence the employer branding. For such purpose, the authors have conducted an exploratory research, where a group of participants has been asked to rate their interest in a company, after viewing solely the online commercial communication (website and Facebook account), while another group has viewed two digital stories produced by two employees of ...

  7. New method of digital angiography

    International Nuclear Information System (INIS)

    Hashiya, Junichi; Korenaga, Takeo; Sakurai, Kenji; Sakai, Fumikazu; Kato, Hisatoyo; Takano, Masao.

    1982-01-01

    New experience of digital angiography using Fuji Intelligent Diagnostic X-ray System was reported. The system utilizes newly developed high sensitivity imaging plate in conjunction with computerized image processor instead of image intensifier-TV series, thus drastically improving image quality. Initial clinical trial was made in 46 cases including intravenous digital subtraction angiography and transcatheter digital arteriography. The advantages of this method were summerized as: 1. better resolution, 2. wider field size, 3. more sophisticated image manipulation program. (author)

  8. Digital Nomads: Employment in the Online Gig Economy

    Directory of Open Access Journals (Sweden)

    Beverly Yuen Thompson

    2018-06-01

    Full Text Available In 1997, Tsugio Makimoto and David Manners published their future-looking manifesto Digital Nomad that, decades later, would present as a manifesto for a lifestyle movement. At the time, businesses and the US government were interested in looking at tele-commuting, productivity, and work-family balance. Critiques of a neoliberal economy provide insight into understanding the context of freelance and online, piecemeal employment. This article examines the types of employment that digital nomads engage in, based on in-depth interviews with thirty-eight self-identified digital nomads. The participants mostly originate from wealthy, industrialized nations, and have many class privileges, but are underemployed compared to what their socio-economic status would historically suggest. As most participants are in the Millennial Generation, an overview of the shifting socio-economic status of this age-cohort is examined in the United States, United Kingdom, Australia, and the European Union – notably their high educational achievements and increasingly precarious employment status. Many of the nomads were working part-time with their own micro-business, with few able to maintain full-time employment. Few have benefits such as healthcare, retirement, unemployment insurance, or family leave. While “freedom” is touted as the benefit of gig-work, by both industry management and digital nomad enthusiasts, this lifestyle marks a shift towards precarious employment – itself not a basis for economic freedom, nor security.

  9. Employer Branding and Talent Management in the Digital Age

    Directory of Open Access Journals (Sweden)

    Alina MIHALCEA

    2017-06-01

    Full Text Available In the digital age, organizations need to reinvent themselves at a structural level and to become agiler. Digital maturity of human resources management implies a shift from traditional paradigm on workplace towards engagement, learning and development of employees and search for talent. This paper focuses on identifying the major trends and strategies concerning talent management programs and development of digital skills for employees and managers. The study reveals that in an open talent economy, employer brand is very important in recruiting and retention of high potential employees and must be focused on learning & leadership development, mobility, rewards and competency systems. At present, in order to obtain a business value, one of the major challenges that HR needs to face is the development of digital skills for managers and employees.

  10. Digital fluorographic method and system

    International Nuclear Information System (INIS)

    Ledley, R.S.

    1985-01-01

    This invention relates to a digital fluorographic method and system, in particular a method and system which calls for the digitization and storage of first and second x-ray picture data derived before and after injection of a contrast medium into a subject. The digitized pictures are stored in separate memories in an associated system, and can be separately whole-picture processed to develop corresponding processed picture data. The resulting data are subtractively combined to produce data corresponding to a pictorial representation of differences between the x-ray picture before and after injection of the contrast medium

  11. How can the digital library contribute to employability?

    DEFF Research Database (Denmark)

    Harbo, Karen; Jensen, Thomas Skov

    2016-01-01

    platforms. A partnership is made between the digital library (partner libraries involved) and the virtual learning environment (educational institutions), based on the above definition of employability. This is done within the framework of Learning Management Systems (LMS) and Massive Open Online Courses......The DEFF project, E-learning, Information literacy and Library services, supports the education policy ambition of enhancing links between education and employment. The project consortium includes libraries from all Danish universities, university colleges and one business academy. Timeframe...... for the project is 2014-16. The project understands employability as: In close cooperation with study programmes libraries will strengthen students’ ability to perform independently and critically in a professional context by being able to identify, collect, evaluate, organize and present information via digital...

  12. How can the digital library contribute to employability?

    DEFF Research Database (Denmark)

    Harbo, Karen; Jensen, Thomas Skov

    2016-01-01

    The DEFF project, E-learning, Information literacy and Library services, supports the education policy ambition of enhancing links between education and employment. The project consortium includes libraries from all Danish universities, university colleges and one business academy. Timeframe...... for the project is 2014-16. The project understands employability as: In close cooperation with study programmes libraries will strengthen students’ ability to perform independently and critically in a professional context by being able to identify, collect, evaluate, organize and present information via digital...... platforms. A partnership is made between the digital library (partner libraries involved) and the virtual learning environment (educational institutions), based on the above definition of employability. This is done within the framework of Learning Management Systems (LMS) and Massive Open Online Courses...

  13. Methods of digital image processing

    International Nuclear Information System (INIS)

    Doeler, W.

    1985-01-01

    Increasing use of computerized methods for diagnostical imaging of radiological problems will open up a wide field of applications for digital image processing. The requirements set by routine diagnostics in medical radiology point to picture data storage and documentation and communication as the main points of interest for application of digital image processing. As to the purely radiological problems, the value of digital image processing is to be sought in the improved interpretability of the image information in those cases where the expert's experience and image interpretation by human visual capacities do not suffice. There are many other domains of imaging in medical physics where digital image processing and evaluation is very useful. The paper reviews the various methods available for a variety of problem solutions, and explains the hardware available for the tasks discussed. (orig.) [de

  14. Digital Storytelling and Employer Branding. An Exploratory Connection

    Directory of Open Access Journals (Sweden)

    Camelia CRIȘAN

    2017-06-01

    Full Text Available Our paper aims at explaining what is digital storytelling and its particular methodology, and how its use in the organizational settings could influence the employer branding. For such purpose, the authors have conducted an exploratory research, where a group of participants has been asked to rate their interest in a company, after viewing solely the online commercial communication (website and Facebook account, while another group has viewed two digital stories produced by two employees of the company. The results of the analysis showed that participants had more positive words to describe the company after viewing the stories, but there were not differences in perception for those who were searching for a job and those who were not searching for the job when exposed solely to the web communication or digital stories.

  15. How can the digital library contribute to employability?

    Directory of Open Access Journals (Sweden)

    Karen Harbo

    2016-12-01

    Full Text Available The DEFF project, E-learning, Information literacy and Library services, supports the education policy ambition of enhancing links between education and employment. The project consortium includes libraries from all Danish universities, university colleges and one business academy. Timeframe for the project is 2014-16. The project understands employability as: In close cooperation with study programmes libraries will strengthen students’ ability to perform independently and critically in a professional context by being able to identify, collect, evaluate, organize and present information via digital platforms. A partnership is made between the digital library (partner libraries involved and the virtual learning environment (educational institutions, based on the above definition of employability. This is done within the framework of Learning Management Systems (LMS and Massive Open Online Courses (MOOCs. The libraries and academic programmes will collaborate to create e-learning objects based on the relevant digital library systems and information resources. Departments from three Danish universities will contribute by strengthening the project participants’ skills in e-didactics and the development of e-learning objects (SDUUP, University of Southern Denmark, developing a range of flexible concepts for the integration of the virtual library into learning environments (IVA, Copenhagen University and evaluating the project’s activities (E-Learning Lab, Aalborg University. Sustainable results include the training of library staff to work together with academic programmes via the virtual learning environments, the development of flexible concepts for integrating the virtual library with study environments and knowledge on how inputs, created by the project for each study programme, should function.

  16. Crystallization method employing microwave radiation

    Energy Technology Data Exchange (ETDEWEB)

    Chu, P; Dwyer, F G; Vartuli, J C

    1992-12-01

    This invention relates to a method of crystallizing materials from aqueous crystallization media. Zeolite materials, both natural and synthetic, have been demonstrated in the past to have catalytic properties for various types of hydrocarbon conversion. Certain zeolitic materials are ordered, porous crystalline metallosilicates having a definite crystalline structure as determined by X-ray diffraction within which there are a number of smaller cavities which may be interconnected by a number of still smaller channels or pores. These cavities and pores are uniform in size within a specific zeolite material. Since the dimensions of these pores are such as to accept for adsorption molecules of certain dimensions while rejecting those of large dimensions, these materials have come to be known as molecular sieves and are utilized in a variety of ways to take advantage of these properties. (author). 3 tabs.

  17. Crystallization method employing microwave radiation

    International Nuclear Information System (INIS)

    Chu, P.; Dwyer, F.G.; Vartuli, J.C.

    1992-01-01

    This invention relates to a method of crystallizing materials from aqueous crystallization media. Zeolite materials, both natural and synthetic, have been demonstrated in the past to have catalytic properties for various types of hydrocarbon conversion. Certain zeolitic materials are ordered, porous crystalline metallosilicates having a definite crystalline structure as determined by X-ray diffraction within which there are a number of smaller cavities which may be interconnected by a number of still smaller channels or pores. These cavities and pores are uniform in size within a specific zeolite material. Since the dimensions of these pores are such as to accept for adsorption molecules of certain dimensions while rejecting those of large dimensions, these materials have come to be known as molecular sieves and are utilized in a variety of ways to take advantage of these properties. (author). 3 tabs

  18. Digital image processing mathematical and computational methods

    CERN Document Server

    Blackledge, J M

    2005-01-01

    This authoritative text (the second part of a complete MSc course) provides mathematical methods required to describe images, image formation and different imaging systems, coupled with the principle techniques used for processing digital images. It is based on a course for postgraduates reading physics, electronic engineering, telecommunications engineering, information technology and computer science. This book relates the methods of processing and interpreting digital images to the 'physics' of imaging systems. Case studies reinforce the methods discussed, with examples of current research

  19. Foundations of Digital Methods : Query Design

    NARCIS (Netherlands)

    Rogers, R.; Schäfer, M.T.; van Es, K.

    2017-01-01

    Broadly speaking digital methods may be considered the deployment of online tools and data for the purposes of social and medium research. More speci cally, they derive from online methods, or methods of the medium, which are reimagined and repurposed for research. The methods to be repurposed are

  20. 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...

  1. Digital signal processing with kernel methods

    CERN Document Server

    Rojo-Alvarez, José Luis; Muñoz-Marí, Jordi; Camps-Valls, Gustavo

    2018-01-01

    A realistic and comprehensive review of joint approaches to machine learning and signal processing algorithms, with application to communications, multimedia, and biomedical engineering systems Digital Signal Processing with Kernel Methods reviews the milestones in the mixing of classical digital signal processing models and advanced kernel machines statistical learning tools. It explains the fundamental concepts from both fields of machine learning and signal processing so that readers can quickly get up to speed in order to begin developing the concepts and application software in their own research. Digital Signal Processing with Kernel Methods provides a comprehensive overview of kernel methods in signal processing, without restriction to any application field. It also offers example applications and detailed benchmarking experiments with real and synthetic datasets throughout. Readers can find further worked examples with Matlab source code on a website developed by the authors. * Presents the necess...

  2. Get the Digital Edge: linking students’ attitudes towards digital literacy and employability at the University of Westminster

    Directory of Open Access Journals (Sweden)

    Emma Woods

    2013-12-01

    Full Text Available The University of Westminster is located in London and is celebrating 175 years as an educational institution this year. A key part of the University's vision is in "building the next generation of highly employable global citizens to shape the future" (University of Westminster, 2013. This vision inspired us to look at the digital literacy skills our students need in order to be highly employable. In Spring 2012, the Information Services department at the University of Westminster secured Jisc funding to run a one year project exploring students' attitudes towards digital literacy and its relationship to employability for our students. The work is being carried out by a project board and a delivery group, which include members of staff from across the University who have an active interest in this area. We named the Project "DigitISE" (Digital Information Skills for Employability and colleagues involved with the project take turns in writing for its blog http://blog.westminster.ac.uk/jisc-employability/blog/ A questionnaire was circulated to find out about students' attitudes towards digital literacy and this was followed up by some focus groups. The headline findings from the survey are that 87.6% of students love digital technology and 81.5% believe themselves to be digitally literate. Attitudes vary significantly between subject areas. For example, with regard to the statement that the digital literacy skills needed in the courses get more complex as students progress through the course, students from the Business School agreed significantly more with this than did students from the School of Law, Social Sciences, Humanities and Languages or Architecture. The focus groups have supported the questionnaire findings and highlighted that students are largely unaware of the training that is already available to them. Ideas of how to market future training more effectively will therefore be an important outcome of this work. A further focus group

  3. Computationally efficient methods for digital control

    NARCIS (Netherlands)

    Guerreiro Tome Antunes, D.J.; Hespanha, J.P.; Silvestre, C.J.; Kataria, N.; Brewer, F.

    2008-01-01

    The problem of designing a digital controller is considered with the novelty of explicitly taking into account the computation cost of the controller implementation. A class of controller emulation methods inspired by numerical analysis is proposed. Through various examples it is shown that these

  4. Optimum survey methods when interviewing employed women.

    Science.gov (United States)

    Dunning, Kari; LeMasters, Grace K

    2009-02-01

    While survey studies have examined bias much is unknown regarding specific subpopulations, especially women workers. A population based phone, Internet, and mail survey of workplace falls during pregnancy was undertaken. Participation by industry and occupation and survey approach and bias, reliability, and incomplete data were examined. Of the 3,997 women surveyed, 71% were employed during their pregnancy. Internet responders were most likely to be employed while pregnant and to report a workplace fall at 8.8% compared to 5.8% and 6.1% for mail and phone respondents. Internet responders had the most missing employment data with company name missing for 17.9% compared to 1.3% for phone responders. Mail surveys were best for recruiting those employed in eight of nine industries, and this was especially true for service occupations. To decrease bias and increase participation, mixed approaches may be useful with particular attention for collecting occupational data. Am. J. Ind. Med. 52:105-112, 2009. (c) 2008 Wiley-Liss, Inc.

  5. Employability, op weg naar een methode

    NARCIS (Netherlands)

    Man, M. de

    1998-01-01

    In dit rapport wordt een model ontworpen voor ontwikkeling van employability in industriële bedrijven, en met name voor assemblage afdelingen. Er wordt een aantal fasen onderscheiden, te weten: de entree fase, waarin contact gelegd wordt met de klant en waarin onderzocht moet worden wat er verlangd

  6. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed

    2012-09-06

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  7. Fully Digital Chaotic Differential Equation-based Systems And Methods

    KAUST Repository

    Radwan, Ahmed Gomaa Ahmed; Zidan, Mohammed A.; Salama, Khaled N.

    2012-01-01

    Various embodiments are provided for fully digital chaotic differential equation-based systems and methods. In one embodiment, among others, a digital circuit includes digital state registers and one or more digital logic modules configured to obtain a first value from two or more of the digital state registers; determine a second value based upon the obtained first values and a chaotic differential equation; and provide the second value to set a state of one of the plurality of digital state registers. In another embodiment, a digital circuit includes digital state registers, digital logic modules configured to obtain outputs from a subset of the digital shift registers and to provide the input based upon a chaotic differential equation for setting a state of at least one of the subset of digital shift registers, and a digital clock configured to provide a clock signal for operating the digital shift registers.

  8. Digital image envelope: method and evaluation

    Science.gov (United States)

    Huang, H. K.; Cao, Fei; Zhou, Michael Z.; Mogel, Greg T.; Liu, Brent J.; Zhou, Xiaoqiang

    2003-05-01

    Health data security, characterized in terms of data privacy, authenticity, and integrity, is a vital issue when digital images and other patient information are transmitted through public networks in telehealth applications such as teleradiology. Mandates for ensuring health data security have been extensively discussed (for example The Health Insurance Portability and Accountability Act, HIPAA) and health informatics guidelines (such as the DICOM standard) are beginning to focus on issues of data continue to be published by organizing bodies in healthcare; however, there has not been a systematic method developed to ensure data security in medical imaging Because data privacy and authenticity are often managed primarily with firewall and password protection, we have focused our research and development on data integrity. We have developed a systematic method of ensuring medical image data integrity across public networks using the concept of the digital envelope. When a medical image is generated regardless of the modality, three processes are performed: the image signature is obtained, the DICOM image header is encrypted, and a digital envelope is formed by combining the signature and the encrypted header. The envelope is encrypted and embedded in the original image. This assures the security of both the image and the patient ID. The embedded image is encrypted again and transmitted across the network. The reverse process is performed at the receiving site. The result is two digital signatures, one from the original image before transmission, and second from the image after transmission. If the signatures are identical, there has been no alteration of the image. This paper concentrates in the method and evaluation of the digital image envelope.

  9. Apparatus and method for managing digital resources by passing digital resource tokens between queues

    Science.gov (United States)

    Crawford, H.J.; Lindenstruth, V.

    1999-06-29

    A method of managing digital resources of a digital system includes the step of reserving token values for certain digital resources in the digital system. A selected token value in a free-buffer-queue is then matched to an incoming digital resource request. The selected token value is then moved to a valid-request-queue. The selected token is subsequently removed from the valid-request-queue to allow a digital agent in the digital system to process the incoming digital resource request associated with the selected token. Thereafter, the selected token is returned to the free-buffer-queue. 6 figs.

  10. Digital dream analysis: a revised method.

    Science.gov (United States)

    Bulkeley, Kelly

    2014-10-01

    This article demonstrates the use of a digital word search method designed to provide greater accuracy, objectivity, and speed in the study of dreams. A revised template of 40 word search categories, built into the website of the Sleep and Dream Database (SDDb), is applied to four "classic" sets of dreams: The male and female "Norm" dreams of Hall and Van de Castle (1966), the "Engine Man" dreams discussed by Hobson (1988), and the "Barb Sanders Baseline 250" dreams examined by Domhoff (2003). A word search analysis of these original dream reports shows that a digital approach can accurately identify many of the same distinctive patterns of content found by previous investigators using much more laborious and time-consuming methods. The results of this study emphasize the compatibility of word search technologies with traditional approaches to dream content analysis. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Development of digital radiographic inspection method in MINT

    International Nuclear Information System (INIS)

    Mohd Ashhar Khalid; Abdul Razak Hamzah; Abdul Aziz Mohamad; Anuar Mikdad Muad; Nolida Yussup; Maslina Mohd Ibrahim

    2002-01-01

    Industrial radiography has been employed for the evaluation of defects, such as cracks, porosity and foreign inclusions found in casting and welds. It has become one of the major techniques in industrial non-destructive testing for the past 40 years. Although this technique has been well developed, further improvement can be implemented especially with the advancement of electronics and computer technology. Digital image processing techniques and application of artificial intelligence methods allow the interpretation of the image to be automated, avoiding the presence of human operators making the inspection system faster, more reliable and reproducible. Numerous works has been reported by various groups on the development of an automated, computer based evaluation algorithms. This paper reports the development and progress of digital radiographic inspection method in MINT. (Author)

  12. COMPARISON OF DIGITAL IMAGE STEGANOGRAPHY METHODS

    Directory of Open Access Journals (Sweden)

    S. A. Seyyedi

    2013-01-01

    Full Text Available Steganography is a method of hiding information in other information of different format (container. There are many steganography techniques with various types of container. In the Internet, digital images are the most popular and frequently used containers. We consider main image steganography techniques and their advantages and disadvantages. We also identify the requirements of a good steganography algorithm and compare various such algorithms.

  13. Uranium manufacturing process employing the electrolytic reduction method

    International Nuclear Information System (INIS)

    Oda, Yoshio; Kazuhare, Manabu; Morimoto, Takeshi.

    1986-01-01

    The present invention related to a uranium manufacturing process that employs the electrolytic reduction method, but particularly to a uranium manufacturing process that employs an electrolytic reduction method requiring low voltage. The process, in which uranium is obtained by means of the electrolytic method and with uranyl acid as the raw material, is prior art

  14. An electromagnetic signals monitoring and analysis wireless platform employing personal digital assistants and pattern analysis techniques

    Science.gov (United States)

    Ninos, K.; Georgiadis, P.; Cavouras, D.; Nomicos, C.

    2010-05-01

    This study presents the design and development of a mobile wireless platform to be used for monitoring and analysis of seismic events and related electromagnetic (EM) signals, employing Personal Digital Assistants (PDAs). A prototype custom-developed application was deployed on a 3G enabled PDA that could connect to the FTP server of the Institute of Geodynamics of the National Observatory of Athens and receive and display EM signals at 4 receiver frequencies (3 KHz (E-W, N-S), 10 KHz (E-W, N-S), 41 MHz and 46 MHz). Signals may originate from any one of the 16 field-stations located around the Greek territory. Employing continuous recordings of EM signals gathered from January 2003 till December 2007, a Support Vector Machines (SVM)-based classification system was designed to distinguish EM precursor signals within noisy background. EM-signals corresponding to recordings preceding major seismic events (Ms≥5R) were segmented, by an experienced scientist, and five features (mean, variance, skewness, kurtosis, and a wavelet based feature), derived from the EM-signals were calculated. These features were used to train the SVM-based classification scheme. The performance of the system was evaluated by the exhaustive search and leave-one-out methods giving 87.2% overall classification accuracy, in correctly identifying EM precursor signals within noisy background employing all calculated features. Due to the insufficient processing power of the PDAs, this task was performed on a typical desktop computer. This optimal trained context of the SVM classifier was then integrated in the PDA based application rendering the platform capable to discriminate between EM precursor signals and noise. System's efficiency was evaluated by an expert who reviewed 1/ multiple EM-signals, up to 18 days prior to corresponding past seismic events, and 2/ the possible EM-activity of a specific region employing the trained SVM classifier. Additionally, the proposed architecture can form a

  15. A smartphone photogrammetry method for digitizing prosthetic socket interiors.

    Science.gov (United States)

    Hernandez, Amaia; Lemaire, Edward

    2017-04-01

    Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person's socket since current 3D scanners have difficulties scanning socket interiors. While dedicated scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and cloud-based photogrammetry services. 15 two-dimensional images of the socket's interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models. 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that is accessible and low-cost, after processing in prosthetic CAD software. Clinical relevance The described method provides a low-cost and accessible means to digitize a socket interior for use in prosthetic CAD/CAM systems, employing a smartphone camera and cloud-based photogrammetry software.

  16. Employing the Gini coefficient to measure participation inequality in treatment-focused Digital Health Social Networks.

    Science.gov (United States)

    van Mierlo, Trevor; Hyatt, Douglas; Ching, Andrew T

    2016-01-01

    Digital Health Social Networks (DHSNs) are common; however, there are few metrics that can be used to identify participation inequality. The objective of this study was to investigate whether the Gini coefficient, an economic measure of statistical dispersion traditionally used to measure income inequality, could be employed to measure DHSN inequality. Quarterly Gini coefficients were derived from four long-standing DHSNs. The combined data set included 625,736 posts that were generated from 15,181 actors over 18,671 days. The range of actors (8-2323), posts (29-28,684), and Gini coefficients (0.15-0.37) varied. Pearson correlations indicated statistically significant associations between number of actors and number of posts (0.527-0.835, p  addiction networks (0.619 and 0.276, p  networks ( t  = -4.305 and -5.934, p  network engagement. Further, mixed-methods research investigating quantitative performance metrics is required.

  17. Digital Libraries--Methods and Applications

    Science.gov (United States)

    Huang, Kuo Hung, Ed.

    2011-01-01

    Digital library is commonly seen as a type of information retrieval system which stores and accesses digital content remotely via computer networks. However, the vision of digital libraries is not limited to technology or management, but user experience. This book is an attempt to share the practical experiences of solutions to the operation of…

  18. Cost-effective bidirectional digitized radio-over-fiber systems employing sigma delta modulation

    Science.gov (United States)

    Lee, Kyung Woon; Jung, HyunDo; Park, Jung Ho

    2016-11-01

    We propose a cost effective digitized radio-over-fiber (D-RoF) system employing a sigma delta modulation (SDM) and a bidirectional transmission technique using phase modulated downlink and intensity modulated uplink. SDM is transparent to different radio access technologies and modulation formats, and more suitable for a downlink of wireless system because a digital to analog converter (DAC) can be avoided at the base station (BS). Also, Central station and BS share the same light source by using a phase modulation for the downlink and an intensity modulation for the uplink transmission. Avoiding DACs and light sources have advantages in terms of cost reduction, power consumption, and compatibility with conventional wireless network structure. We have designed a cost effective bidirectional D-RoF system using a low pass SDM and measured the downlink and uplink transmission performance in terms of error vector magnitude, signal spectra, and constellations, which are based on the 10MHz LTE 64-QAM standard.

  19. Measuring digit lengths with 3D digital stereophotogrammetry: A comparison across methods.

    Science.gov (United States)

    Gremba, Allison; Weinberg, Seth M

    2018-05-09

    We compared digital 3D stereophotogrammetry to more traditional measurement methods (direct anthropometry and 2D scanning) to capture digit lengths and ratios. The length of the second and fourth digits was measured by each method and the second-to-fourth ratio was calculated. For each digit measurement, intraobserver agreement was calculated for each of the three collection methods. Further, measurements from the three methods were compared directly to one another. Agreement statistics included the intraclass correlation coefficient (ICC) and technical error of measurement (TEM). Intraobserver agreement statistics for the digit length measurements were high for all three methods; ICC values exceeded 0.97 and TEM values were below 1 mm. For digit ratio, intraobserver agreement was also acceptable for all methods, with direct anthropometry exhibiting lower agreement (ICC = 0.87) compared to indirect methods. For the comparison across methods, the overall agreement was high for digit length measurements (ICC values ranging from 0.93 to 0.98; TEM values below 2 mm). For digit ratios, high agreement was observed between the two indirect methods (ICC = 0.93), whereas indirect methods showed lower agreement when compared to direct anthropometry (ICC < 0.75). Digit measurements and derived ratios from 3D stereophotogrammetry showed high intraobserver agreement (similar to more traditional methods) suggesting that landmarks could be placed reliably on 3D hand surface images. While digit length measurements were found to be comparable across all three methods, ratios derived from direct anthropometry tended to be higher than those calculated indirectly from 2D or 3D images. © 2018 Wiley Periodicals, Inc.

  20. The Process of Adapting the Employer Brand to Attract the Right Employees : A Case Study of How SEB Uses Employer Branding to Go Digital

    OpenAIRE

    Simon, Tabea; Ferhatovic, Amela

    2016-01-01

    Companies within the banking industry are facing the challenge to attract new competences in order to react to the forces of digitization. This paper examines how employer branding is used as a tool to achieve this through appealing to a broader target group. It also identifies problems that can arise in this process. We extend the theoretical knowledge on this topic by developing a theoretical framework, which combines corporate brand, employer branding, industry image and P-O fit literature...

  1. Digital methods for mediated discourse analysis

    DEFF Research Database (Denmark)

    Kjær, Malene; Larsen, Malene Charlotte

    2015-01-01

    , restrictions or privately mediated settings. Having used mediated discourse analysis (Scollon 2002, Scollon & Scollon, 2004) as a framework in two different research projects, we show how the framework, in correlation with digital resources for data gathering, provides new understandings of 1) the daily......In this paper we discuss methodological strategies for collecting multimodal data using digital resources. The aim is to show how digital resources can provide ethnographic insights into mediated actions (Scollon, 2002) that can otherwise be difficult to observe or engage in, due to, for instance......) and online questionnaire data in order to capture mediated actions and discourses in practice....

  2. Two-Step Injection Method for Collecting Digital Evidence in Digital Forensics

    Directory of Open Access Journals (Sweden)

    Nana Rachmana Syambas

    2015-01-01

    Full Text Available In digital forensic investigations, the investigators take digital evidence from computers, laptops or other electronic goods. There are many complications when a suspect or related person does not want to cooperate or has removed digital evidence. A lot of research has been done with the goal of retrieving data from flash memory or other digital storage media from which the content has been deleted. Unfortunately, such methods cannot guarantee that all data will be recovered. Most data can only be recovered partially and sometimes not perfectly, so that some or all files cannot be opened. This paper proposes the development of a new method for the retrieval of digital evidence called the Two-Step Injection method (TSI. It focuses on the prevention of the loss of digital evidence through the deletion of data by suspects or other parties. The advantage of this method is that the system works in secret and can be combined with other digital evidence applications that already exist, so that the accuracy and completeness of the resulting digital evidence can be improved. An experiment to test the effectiveness of the method was set up. The developed TSI system worked properly and had a 100% success rate.

  3. Why Map Issues? On Controversy Analysis as a Digital Method.

    Science.gov (United States)

    Marres, Noortje

    2015-09-01

    This article takes stock of recent efforts to implement controversy analysis as a digital method in the study of science, technology, and society (STS) and beyond and outlines a distinctive approach to address the problem of digital bias. Digital media technologies exert significant influence on the enactment of controversy in online settings, and this risks undermining the substantive focus of controversy analysis conducted by digital means. To address this problem, I propose a shift in thematic focus from controversy analysis to issue mapping. The article begins by distinguishing between three broad frameworks that currently guide the development of controversy analysis as a digital method, namely, demarcationist, discursive, and empiricist. Each has been adopted in STS, but only the last one offers a digital "move beyond impartiality." I demonstrate this approach by analyzing issues of Internet governance with the aid of the social media platform Twitter.

  4. Digital methods for the history of psychology: Introduction and resources.

    Science.gov (United States)

    Fox Lee, Shayna

    2016-02-01

    At the York University Digital History of Psychology Laboratory, we have been working on projects that explore what digital methodologies have to offer historical research in our field. This piece provides perspective on the history and theory of digital history, as well as introductory resources for those who are curious about incorporating these methods into their own work. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Research based on matlab method of digital trapezoidal shaping filter

    International Nuclear Information System (INIS)

    Zhou Qinghua; Zhang Ruanyu; Li Taihua

    2008-01-01

    In order to develop digital shaping system fast and conveniently, the paper presents the method of optimizing the trapezoidal shaping filter's parameters by using MATLAB, and discusses the affections of the parameters to the shaping result by this method. (authors)

  6. A logic circuit for solving linear function by digital method

    International Nuclear Information System (INIS)

    Ma Yonghe

    1986-01-01

    A mathematical method for determining the linear relation of physical quantity with rediation intensity is described. A logic circuit has been designed for solving linear function by digital method. Some applications and the circuit function are discussed

  7. Developing digital technologies for university mathematics by applying participatory design methods

    DEFF Research Database (Denmark)

    Triantafyllou, Eva; Timcenko, Olga

    2013-01-01

    This paper presents our research efforts to develop digital technologies for undergraduate university mathematics. We employ participatory design methods in order to involve teachers and students in the design of such technologies. The results of the first round of our design are included...

  8. Method for analysis of failure of material employing imaging

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, H.J.; Wellington, S.L.; de Waal, J.A.

    1989-12-05

    This patent describes a method for determining at least one preselected property of a sample of material employing an imaging apparatus. It comprises: imaging the sample during the application of known preselected forces to the sample, and determining density in the sample responsive to the preselected forces.

  9. A simple method of digitizing analog scintigrams for quantification and digital archiving

    International Nuclear Information System (INIS)

    Schramm, M.; Kaempfer, B.; Wolf, H.; Clausen, M.; Wendhausen, H.; Henze, E.

    1993-01-01

    This study was undertaken to evaluate a quick, reliable and cheap method of digitizing analog scintigrams. 40 whole-body bone scintigrams were obtained simultaneously in analog and genuine digital format. The analog scans on X-ray film were then digitized seecondarily by three different methods: 300 dpi flatbed scanning, high-resolution camera scanning and camcorder recording. A simple exposure approach using a light box, a cheap camcorder, a PC and image grabber hard- and software proved to be optimal. Visual interpretation showed no differences in clinical findings when comparing the analog images with their secondarily digitized counterparts. To test the possibility of quantification, 126 equivalent ROIs were drawn both in the genuine digital and the secondarily digitized images. Comparing the ROI count to whole-body count percentage of the corresponding ROIs showed the correlation to be linear. The evaluation of phantom studies showed the linear correlation to be true within a wide activity range. Thus, secondary digitalization of analog scintigrams is an easy, cheap and reliable method of archiving images and allows secondary digital quantification. (orig.) [de

  10. [A simple method of digitizing analog scintigrams for quantification and digital archiving].

    Science.gov (United States)

    Schramm, M; Kämpfer, B; Wolf, H; Clausen, M; Wendhausen, H; Henze, E

    1993-02-01

    This study was undertaken to evaluate a quick, reliable and cheap method of digitizing analog scintigrams. 40 whole-body bone scintigrams were obtained simultaneously in analog and genuine digital format. The analog scans on x-ray film were then digitized secondarily by three different methods: 300 dpi flat-bed scanning, high-resolution camera scanning and camcorder recording. A simple exposure approach using a light box, a cheap camcorder, a PC and image grabber hard- and software proved to be optimal. Visual interpretation showed no differences in clinical findings when comparing the analog images with their secondarily digitized counterparts. To test the possibility of quantification, 126 equivalent ROIs were drawn both in the genuine digital and the secondarily digitized images. Comparing the ROI count to whole-body count percentage of the corresponding ROIs showed the correlation to be linear. The evaluation of phantom studies showed the linear correlation to be true within a wide activity range. Thus, secondary digitalization of analog scintigrams is an easy, cheap and reliable method of archiving images and allows secondary digital quantification.

  11. College Students; Justification for Digital Piracy: A Mixed Methods Study

    Science.gov (United States)

    Yu, Szde

    2012-01-01

    A mixed methods project was devoted to understanding college students' justification for digital piracy. The project consisted of two studies, a qualitative one and a quantitative one. Qualitative interviews were conducted to identify main themes in students' justification for digital piracy, and then the findings were tested in a quantitative…

  12. Digital Threat and Vulnerability Management: The SVIDT Method

    Directory of Open Access Journals (Sweden)

    Roland W. Scholz

    2017-04-01

    Full Text Available The Digital Revolution is inducing major threats to many types of human systems. We present the SVIDT method (a Strengths, Vulnerability, and Intervention Assessment related to Digital Threats for managing the vulnerabilities of human systems with respect to digital threats and changes. The method first performs a multilevel system–actor analysis for assessing vulnerabilities and strengths with respect to digital threats. Then, the method identifies threat scenarios that may become real. By constructing, evaluating, and launching interventions against all identified digital threats and their critical negative outcomes, the resilience of a specific human system can be improved. The evaluation of interventions is done when strengthening the adaptive capacity, i.e., a system’s capability to cope with negative outcomes that may take place in the future. The SVIDT method is embedded in the framework of coupled human–environment systems, the theory of risk and vulnerability assessment, types of adaptation (assimilation vs. accommodation, and a comprehensive sustainability evaluation. The SVIDT method is exemplarily applied to an enterprise (i.e., a Swiss casino for which online gaming has become an essential digital-business field. The discussion reflects on the specifics of digital threats and discusses both the potential benefits and limitations of the SVIDT method.

  13. Perceptual digital imaging methods and applications

    CERN Document Server

    Lukac, Rastislav

    2012-01-01

    Visual perception is a complex process requiring interaction between the receptors in the eye that sense the stimulus and the neural system and the brain that are responsible for communicating and interpreting the sensed visual information. This process involves several physical, neural, and cognitive phenomena whose understanding is essential to design effective and computationally efficient imaging solutions. Building on advances in computer vision, image and video processing, neuroscience, and information engineering, perceptual digital imaging greatly enhances the capabilities of tradition

  14. Development of digital image correlation method to analyse crack ...

    Indian Academy of Sciences (India)

    samples were performed to verify the performance of the digital image correlation method. ... development cannot be measured accurately. ..... Mendelson A 1983 Plasticity: Theory and application (USA: Krieger Publishing company Malabar,.

  15. Employment of kernel methods on wind turbine power performance assessment

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Sweeney, Christian Walsted; Marhadi, Kun S.

    2015-01-01

    A power performance assessment technique is developed for the detection of power production discrepancies in wind turbines. The method employs a widely used nonparametric pattern recognition technique, the kernel methods. The evaluation is based on the trending of an extracted feature from...... the kernel matrix, called similarity index, which is introduced by the authors for the first time. The operation of the turbine and consequently the computation of the similarity indexes is classified into five power bins offering better resolution and thus more consistent root cause analysis. The accurate...

  16. Dynamic strain analysis of structures employing digital signal processing, storage and display

    Energy Technology Data Exchange (ETDEWEB)

    Patwardhan, P K; Misra, V M; Kumar, Surendra

    1975-01-01

    A multi-channel digital technique has been adopted for analysing wave patterns of stresses and strains in structures, particularly under dynamic conditions. This technique provides adequate signal to noise discrimination and high sensitivity for very small (few milli-volts) and slow varying signals (few Hz to 100 Hz.), and A-D conversion accompined by live display during the course of data gathering and computer compatible output. This system also provides fast response because of inherent 50 MHz digitising speed and a large dynamic range of 1024 discrete signal steps. The signals can be suitably fed to the A-D converter (50 MHz) or can be analysed employing frequency modulation techniques and time mode operation of the analyser. The data can be gathered in the field on cassette tapes and replayed in the laboratory for detailed analysis. This technique would provide a versatile system for dynamic analysis of structures under varying conditions. e.g. structures in nuclear power systems, such as testing of end fittings, calandria, vibration testing and measurements exploying pressure transducers.

  17. Dynamic strain analysis of structures employing digital signal processing, storage and display

    International Nuclear Information System (INIS)

    Patwardhan, P.K.; Misra, V.M.; Kumar, Surendra

    1975-01-01

    A multi-channel digital technique has been adopted for analysing wave patterns of stresses and strains in structures, particularly under dynamic conditions. This technique provides adequate signal to noise discrimination and high sensitivity for very small (few milli-volts) and slow varying signals (few Hz to 100 Hz.), A-D conversion accompined by live display during the course of data gathering and computer compatible output. This system also provides fast response because of inherent 50 MHz digitising speed and a large dynamic range of 1024 discrete signal steps. The signals can be suitably fed to the A-D converter (50 MHz) or can be analysed employing frequency modulation techniques and time mode operation of the analyser. The data can be gathered in the field on cassette tapes and replayed in the laboratory for detailed analysis. This technique would provide a versatile system for dynamic analysis of structures under varying conditions. e.g. structures in nuclear power systems, such as testing of end fittings, calandria, vibration testing and measurements exploying pressure transducers. (author)

  18. Ensemble methods for handwritten digit recognition

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Liisberg, Christian; Salamon, P.

    1992-01-01

    Neural network ensembles are applied to handwritten digit recognition. The individual networks of the ensemble are combinations of sparse look-up tables (LUTs) with random receptive fields. It is shown that the consensus of a group of networks outperforms the best individual of the ensemble....... It is further shown that it is possible to estimate the ensemble performance as well as the learning curve on a medium-size database. In addition the authors present preliminary analysis of experiments on a large database and show that state-of-the-art performance can be obtained using the ensemble approach...... by optimizing the receptive fields. It is concluded that it is possible to improve performance significantly by introducing moderate-size ensembles; in particular, a 20-25% improvement has been found. The ensemble random LUTs, when trained on a medium-size database, reach a performance (without rejects) of 94...

  19. A review of digital radiological methods

    International Nuclear Information System (INIS)

    Halmshaw, R.; Ridyard, J.N.A.

    1990-01-01

    The development of more powerful, cost-effective computer systems in recent years has enabled digital radiography to become a reality. This is not only for adding on to real-time fluoroscopic systems as a useful way of averaging image data to reduce noise and perform various manipulation functions, but also the more powerful wide dynamic range discrete-detector systems where one can extract far more information from an X-ray exposure than was formerly possible. This type of detector is essential for computer tomography and back-scatter tomography, but when applied to classical 2-dimensional images results in some unique advantages not achievable with film. These newer systems are capable of matching or exceeding film performance, especially at high X-ray energies. (author)

  20. Research on coding and decoding method for digital levels

    Energy Technology Data Exchange (ETDEWEB)

    Tu Lifen; Zhong Sidong

    2011-01-20

    A new coding and decoding method for digital levels is proposed. It is based on an area-array CCD sensor and adopts mixed coding technology. By taking advantage of redundant information in a digital image signal, the contradiction that the field of view and image resolution restrict each other in a digital level measurement is overcome, and the geodetic leveling becomes easier. The experimental results demonstrate that the uncertainty of measurement is 1mm when the measuring range is between 2m and 100m, which can meet practical needs.

  1. Research on coding and decoding method for digital levels.

    Science.gov (United States)

    Tu, Li-fen; Zhong, Si-dong

    2011-01-20

    A new coding and decoding method for digital levels is proposed. It is based on an area-array CCD sensor and adopts mixed coding technology. By taking advantage of redundant information in a digital image signal, the contradiction that the field of view and image resolution restrict each other in a digital level measurement is overcome, and the geodetic leveling becomes easier. The experimental results demonstrate that the uncertainty of measurement is 1 mm when the measuring range is between 2 m and 100 m, which can meet practical needs.

  2. Systems and methods for self-synchronized digital sampling

    Science.gov (United States)

    Samson, Jr., John R. (Inventor)

    2008-01-01

    Systems and methods for self-synchronized data sampling are provided. In one embodiment, a system for capturing synchronous data samples is provided. The system includes an analog to digital converter adapted to capture signals from one or more sensors and convert the signals into a stream of digital data samples at a sampling frequency determined by a sampling control signal; and a synchronizer coupled to the analog to digital converter and adapted to receive a rotational frequency signal from a rotating machine, wherein the synchronizer is further adapted to generate the sampling control signal, and wherein the sampling control signal is based on the rotational frequency signal.

  3. A digital processing method for the analysis of complex nuclear spectra

    International Nuclear Information System (INIS)

    Madan, V.K.; Abani, M.C.; Bairi, B.R.

    1994-01-01

    This paper describes a digital processing method using frequency power spectra for the analysis of complex nuclear spectra. The power spectra were estimated by employing modified discrete Fourier transform. The method was applied to observed spectral envelopes. The results for separating closely-spaced doublets in nuclear spectra of low statistical precision compared favorably with those obtained by using a popular peak fitting program SAMPO. The paper also describes limitations of the peak fitting methods. It describes the advantages of digital processing techniques for type II digital signals including nuclear spectra. A compact computer program occupying less than 2.5 kByte of memory space was written in BASIC for the processing of observed spectral envelopes. (orig.)

  4. Calibration of high resolution digital camera based on different photogrammetric methods

    International Nuclear Information System (INIS)

    Hamid, N F A; Ahmad, A

    2014-01-01

    This paper presents method of calibrating high-resolution digital camera based on different configuration which comprised of stereo and convergent. Both methods are performed in the laboratory and in the field calibration. Laboratory calibration is based on a 3D test field where a calibration plate of dimension 0.4 m × 0.4 m with grid of targets at different height is used. For field calibration, it uses the same concept of 3D test field which comprised of 81 target points located on a flat ground and the dimension is 9 m × 9 m. In this study, a non-metric high resolution digital camera called Canon Power Shot SX230 HS was calibrated in the laboratory and in the field using different configuration for data acquisition. The aim of the calibration is to investigate the behavior of the internal digital camera whether all the digital camera parameters such as focal length, principal point and other parameters remain the same or vice-versa. In the laboratory, a scale bar is placed in the test field for scaling the image and approximate coordinates were used for calibration process. Similar method is utilized in the field calibration. For both test fields, the digital images were acquired within short period using stereo and convergent configuration. For field calibration, aerial digital images were acquired using unmanned aerial vehicle (UAV) system. All the images were processed using photogrammetric calibration software. Different calibration results were obtained for both laboratory and field calibrations. The accuracy of the results is evaluated based on standard deviation. In general, for photogrammetric applications and other applications the digital camera must be calibrated for obtaining accurate measurement or results. The best method of calibration depends on the type of applications. Finally, for most applications the digital camera is calibrated on site, hence, field calibration is the best method of calibration and could be employed for obtaining accurate

  5. Review of training methods employed in nuclear fuel fabrication plants

    International Nuclear Information System (INIS)

    Box, W.D.; Browder, F.N.

    1975-01-01

    A search of the literature through the Nuclear Safety Information Center revealed that 86 percent of the incidents that have occurred in fuel fabrication plants can be traced directly or indirectly to insufficient operator training. In view of these findings, a review was made of the training programs now employed by the nuclear fuel fabrication industry. Most companies give the new employee approximately 20 hours of orientation courses, followed by 60 to 80 hours of on-the-job training. It was concluded that these training programs should be expanded in both scope and depth. A proposed program is outlined to offer guidance in improving the basic methods currently in use

  6. Measurement methods to build up the digital optical twin

    Science.gov (United States)

    Prochnau, Marcel; Holzbrink, Michael; Wang, Wenxin; Holters, Martin; Stollenwerk, Jochen; Loosen, Peter

    2018-02-01

    The realization of the Digital Optical Twin (DOT), which is in short the digital representation of the physical state of an optical system, is particularly useful in the context of an automated assembly process of optical systems. During the assembly process, the physical system status of the optical system is continuously measured and compared with the digital model. In case of deviations between physical state and the digital model, the latter one is adapted to match the physical state. To reach the goal described above, in a first step measurement/characterization technologies concerning their suitability to generate a precise digital twin of an existing optical system have to be identified and evaluated. This paper gives an overview of possible characterization methods and, finally, shows first results of evaluated, compared methods (e.g. spot-radius, MTF, Zernike-polynomials), to create a DOT. The focus initially lies on the unequivocalness of the optimization results as well as on the computational time required for the optimization to reach the characterized system state. Possible sources of error are the measurement accuracy (to characterize the system) , execution time of the measurement, time needed to map the digital to the physical world (optimization step) as well as interface possibilities to integrate the measurement tool into an assembly cell. Moreover, it is to be discussed whether the used measurement methods are suitable for a `seamless' integration into an assembly cell.

  7. A full digital approach to the TDCR method

    International Nuclear Information System (INIS)

    Mini, Giuliano; Pepe, Francesco; Tintori, Carlo; Capogni, Marco

    2014-01-01

    Current state of the art solutions based on the Triple to Double Coincidence Ratio method are generally large size, heavy-weight and not transportable systems. This is due, on one side, to large detectors and scintillation chambers and, on the other, to bulky analog electronics for data acquisition. CAEN developed a new, full digital approach to TDCR technique based on a portable, stand-alone, high-speed multichannel digitizer, on-board Digital Pulse Processing and dedicated DAQ software that emulates the well-known MAC3 analog board. - Highlights: • CAEN Desktop Digitizers used to emulate the MAC3 analog board in TDCR acquisition. • Spectroscopic application of the CAEN digitizers to the TDCR for charge spectra. • Development of two different softwares by CAEN and ENEA-INMRI for TDCR analysis. • Single electron peak obtained by CAEN digitizer and ENEA-INMRI portable TDCR. • Measurements of 90 Sr/ 90 Y by the new TDCR device equipped with CAEN digitizers

  8. Digital phase-shifting atomic force microscope Moire method

    International Nuclear Information System (INIS)

    Liu Chiaming; Chen Lienwen

    2005-01-01

    In this study, the digital atomic force microscope (AFM) Moire method with phase-shifting technology is established to measure the in-plane displacement and strain fields. The Moire pattern is generated by the interference between the specimen grating and the virtual reference grating formed by digital image processes. The overlapped image is filtered by two-dimensional wavelet transformation to obtain the clear interference Moire patterns. The four-step phase-shifting method is realized by translating the phase of the virtual reference grating from 0 to 2π. The principle of the digital AFM Moire method and the phase-shifting technology are described in detail. Experimental results show that this method is convenient to use and efficient in realizing the microscale measurement

  9. Gamma ray spectroscopy employing divalent europium-doped alkaline earth halides and digital readout for accurate histogramming

    Science.gov (United States)

    Cherepy, Nerine Jane; Payne, Stephen Anthony; Drury, Owen B; Sturm, Benjamin W

    2014-11-11

    A scintillator radiation detector system according to one embodiment includes a scintillator; and a processing device for processing pulse traces corresponding to light pulses from the scintillator, wherein pulse digitization is used to improve energy resolution of the system. A scintillator radiation detector system according to another embodiment includes a processing device for fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times and performing a direct integration of fit parameters. A method according to yet another embodiment includes processing pulse traces corresponding to light pulses from a scintillator, wherein pulse digitization is used to improve energy resolution of the system. A method in a further embodiment includes fitting digitized scintillation waveforms to an algorithm based on identifying rise and decay times; and performing a direct integration of fit parameters. Additional systems and methods are also presented.

  10. Design Strategy for a Pipelined ADC Employing Digital Post-correction

    NARCIS (Netherlands)

    Harpe, P.J.A.; Zanikopoulos, A.; Hegt, J.A.; Roermund, van A.H.M.

    2004-01-01

    This paper describes how the usage of digital post-correction techniques in pipelined analog-to-digital converters (ADC's) can be exploited optimally during the design-phase of the converter. It is known that post-correction algorithms reduce the influence of several cir- cuit impairments on the

  11. Review of training methods employed in nuclear fuel fabrication plants

    International Nuclear Information System (INIS)

    Box, W.D.; Browder, F.N.

    A search of the literature through the Nuclear Safety Information Center revealed that approximately 86 percent of the incidents that have occurred in fuel fabrication plants can be traced directly or indirectly to insufficient operator training. In view of these findings, a review was made of the training programs now employed by the nuclear fuel fabrication industry. Most companies give the new employee approximately 20 h of orientation courses, followed by 60 to 80 h of on-the-job training. It was concluded that these training programs should be expanded in both scope and depth. A proposed program is outlined to offer guidance in improving the basic methods currently in use. (U.S.)

  12. Software V ampersand V methods for digital plant protection system

    International Nuclear Information System (INIS)

    Kim, Hung-Jun; Han, Jai-Bok; Chun, Chong-Son; Kim, Sung; Kim, Kern-Joong.

    1997-01-01

    Careful thought must be given to software design in the development of digital based systems that play a critical role in the successful operation of nuclear power plants. To evaluate the software verification and validation methods as well as to verify its system performance capabilities for the upgrade instrumentation and control system in the Korean future nuclear power plants, the prototype Digital Plant, Protection System (DPPS) based on the Programmable Logic Controller (PLC) has been constructed. The system design description and features are briefly presented, and the software design and software verification and validation methods are focused. 6 refs., 2 figs

  13. Digital spectral analysis parametric, non-parametric and advanced methods

    CERN Document Server

    Castanié, Francis

    2013-01-01

    Digital Spectral Analysis provides a single source that offers complete coverage of the spectral analysis domain. This self-contained work includes details on advanced topics that are usually presented in scattered sources throughout the literature.The theoretical principles necessary for the understanding of spectral analysis are discussed in the first four chapters: fundamentals, digital signal processing, estimation in spectral analysis, and time-series models.An entire chapter is devoted to the non-parametric methods most widely used in industry.High resolution methods a

  14. A Critical Analysis of the Conventionally Employed Creep Lifing Methods.

    Science.gov (United States)

    Abdallah, Zakaria; Gray, Veronica; Whittaker, Mark; Perkins, Karen

    2014-04-29

    The deformation of structural alloys presents problems for power plants and aerospace applications due to the demand for elevated temperatures for higher efficiencies and reductions in greenhouse gas emissions. The materials used in such applications experience harsh environments which may lead to deformation and failure of critical components. To avoid such catastrophic failures and also increase efficiency, future designs must utilise novel/improved alloy systems with enhanced temperature capability. In recognising this issue, a detailed understanding of creep is essential for the success of these designs by ensuring components do not experience excessive deformation which may ultimately lead to failure. To achieve this, a variety of parametric methods have been developed to quantify creep and creep fracture in high temperature applications. This study reviews a number of well-known traditionally employed creep lifing methods with some more recent approaches also included. The first section of this paper focuses on predicting the long-term creep rupture properties which is an area of interest for the power generation sector. The second section looks at pre-defined strains and the re-production of full creep curves based on available data which is pertinent to the aerospace industry where components are replaced before failure.

  15. Comparison of the spatial landmark scatter of various 3D digitalization methods.

    Science.gov (United States)

    Boldt, Florian; Weinzierl, Christian; Hertrich, Klaus; Hirschfelder, Ursula

    2009-05-01

    The aim of this study was to compare four different three-dimensional digitalization methods on the basis of the complex anatomical surface of a cleft lip and palate plaster cast, and to ascertain their accuracy when positioning 3D landmarks. A cleft lip and palate plaster cast was digitalized with the SCAN3D photo-optical scanner, the OPTIX 400S laser-optical scanner, the Somatom Sensation 64 computed tomography system and the MicroScribe MLX 3-axis articulated-arm digitizer. First, four examiners appraised by individual visual inspection the surface detail reproduction of the three non-tactile digitalization methods in comparison to the reference plaster cast. The four examiners then localized the landmarks five times at intervals of 2 weeks. This involved simply copying, or spatially tracing, the landmarks from a reference plaster cast to each model digitally reproduced by each digitalization method. Statistical analysis of the landmark distribution specific to each method was performed based on the 3D coordinates of the positioned landmarks. Visual evaluation of surface detail conformity assigned the photo-optical digitalization method an average score of 1.5, the highest subjectively-determined conformity (surpassing computer tomographic and laser-optical methods). The tactile scanning method revealed the lowest degree of 3D landmark scatter, 0.12 mm, and at 1.01 mm the lowest maximum 3D landmark scatter; this was followed by the computer tomographic, photo-optical and laser-optical methods (in that order). This study demonstrates that the landmarks' precision and reproducibility are determined by the complexity of the reference-model surface as well as the digital surface quality and individual ability of each evaluator to capture 3D spatial relationships. The differences in the 3D-landmark scatter values and lowest maximum 3D-landmark scatter between the best and the worst methods showed minor differences. The measurement results in this study reveal that it

  16. Digital Resonant Controller based on Modified Tustin Discretization Method

    Directory of Open Access Journals (Sweden)

    STOJIC, D.

    2016-11-01

    Full Text Available Resonant controllers are used in power converter voltage and current control due to their simplicity and accuracy. However, digital implementation of resonant controllers introduces problems related to zero and pole mapping from the continuous to the discrete time domain. Namely, some discretization methods introduce significant errors in the digital controller resonant frequency, resulting in the loss of the asymptotic AC reference tracking, especially at high resonant frequencies. The delay compensation typical for resonant controllers can also be compromised. Based on the existing analysis, it can be concluded that the Tustin discretization with frequency prewarping represents a preferable choice from the point of view of the resonant frequency accuracy. However, this discretization method has a shortcoming in applications that require real-time frequency adaptation, since complex trigonometric evaluation is required for each frequency change. In order to overcome this problem, in this paper the modified Tustin discretization method is proposed based on the Taylor series approximation of the frequency prewarping function. By comparing the novel discretization method with commonly used two-integrator-based proportional-resonant (PR digital controllers, it is shown that the resulting digital controller resonant frequency and time delay compensation errors are significantly reduced for the novel controller.

  17. Cardiac imaging systems and methods employing computerized tomographic scanning

    International Nuclear Information System (INIS)

    Richey, J.B.; Wake, R.H.; Walters, R.G.; Hunt, W.F.; Cool, S.L.

    1980-01-01

    The invention relates to cardiac imaging systems and methods employing computerised tomographic scanning. Apparatus is described which allows an image of the radiation attenuation of the heart at a desired phase of the cardiac cycle. The patients ECG signal can be used in a transverse-and-rotate type CT scanner as a time base, so that the beam reaches the heart at a desired phase of the cardiac cycle, or, in a purely rotational-type CT scanner continuously generated scan data is only stored for corresponding phases of successive cardiac cycles. Alternatively, gating of the beams themselves by shuttering or switching the power supply can be controlled by the ECG signal. A pacemaker is used to stabilize the cardiac period. Also used is a system for recognising unacceptable variations in the cardiac period and discarding corresponding scan data. In a transverse-and-rotate type fan-beam CT scanner, the effective beam width is narrowed to reduce the duration of the traverse of the heart. (U.K.)

  18. Periodic local MP2 method employing orbital specific virtuals

    International Nuclear Information System (INIS)

    Usvyat, Denis; Schütz, Martin; Maschio, Lorenzo

    2015-01-01

    We introduce orbital specific virtuals (OSVs) to represent the truncated pair-specific virtual space in periodic local Møller-Plesset perturbation theory of second order (LMP2). The OSVs are constructed by diagonalization of the LMP2 amplitude matrices which correspond to diagonal Wannier-function (WF) pairs. Only a subset of these OSVs is adopted for the subsequent OSV-LMP2 calculation, namely, those with largest contribution to the diagonal pair correlation energy and with the accumulated value of these contributions reaching a certain accuracy. The virtual space for a general (non diagonal) pair is spanned by the union of the two OSV sets related to the individual WFs of the pair. In the periodic LMP2 method, the diagonal LMP2 amplitude matrices needed for the construction of the OSVs are calculated in the basis of projected atomic orbitals (PAOs), employing very large PAO domains. It turns out that the OSVs are excellent to describe short range correlation, yet less appropriate for long range van der Waals correlation. In order to compensate for this bias towards short range correlation, we augment the virtual space spanned by the OSVs by the most diffuse PAOs of the corresponding minimal PAO domain. The Fock and overlap matrices in OSV basis are constructed in the reciprocal space. The 4-index electron repulsion integrals are calculated by local density fitting and, for distant pairs, via multipole approximation. New procedures for determining the fit-domains and the distant-pair lists, leading to higher efficiency in the 4-index integral evaluation, have been implemented. Generally, and in contrast to our previous PAO based periodic LMP2 method, the OSV-LMP2 method does not require anymore great care in the specification of the individual domains (to get a balanced description when calculating energy differences) and is in that sense a black box procedure. Discontinuities in potential energy surfaces, which may occur for PAO-based calculations if one is not

  19. Periodic local MP2 method employing orbital specific virtuals

    Energy Technology Data Exchange (ETDEWEB)

    Usvyat, Denis, E-mail: denis.usvyat@chemie.uni-regensburg.de; Schütz, Martin, E-mail: martin.schuetz@chemie.uni-regensburg.de [Institute for Physical and Theoretical Chemistry, Universität Regensburg, Universitätsstraße 31, D-93040 Regensburg (Germany); Maschio, Lorenzo, E-mail: lorenzo.maschio@unito.it [Dipartimento di Chimica, and Centre of Excellence NIS (Nanostructured Interfaces and Surfaces), Università di Torino, via Giuria 5, I-10125 Torino (Italy)

    2015-09-14

    We introduce orbital specific virtuals (OSVs) to represent the truncated pair-specific virtual space in periodic local Møller-Plesset perturbation theory of second order (LMP2). The OSVs are constructed by diagonalization of the LMP2 amplitude matrices which correspond to diagonal Wannier-function (WF) pairs. Only a subset of these OSVs is adopted for the subsequent OSV-LMP2 calculation, namely, those with largest contribution to the diagonal pair correlation energy and with the accumulated value of these contributions reaching a certain accuracy. The virtual space for a general (non diagonal) pair is spanned by the union of the two OSV sets related to the individual WFs of the pair. In the periodic LMP2 method, the diagonal LMP2 amplitude matrices needed for the construction of the OSVs are calculated in the basis of projected atomic orbitals (PAOs), employing very large PAO domains. It turns out that the OSVs are excellent to describe short range correlation, yet less appropriate for long range van der Waals correlation. In order to compensate for this bias towards short range correlation, we augment the virtual space spanned by the OSVs by the most diffuse PAOs of the corresponding minimal PAO domain. The Fock and overlap matrices in OSV basis are constructed in the reciprocal space. The 4-index electron repulsion integrals are calculated by local density fitting and, for distant pairs, via multipole approximation. New procedures for determining the fit-domains and the distant-pair lists, leading to higher efficiency in the 4-index integral evaluation, have been implemented. Generally, and in contrast to our previous PAO based periodic LMP2 method, the OSV-LMP2 method does not require anymore great care in the specification of the individual domains (to get a balanced description when calculating energy differences) and is in that sense a black box procedure. Discontinuities in potential energy surfaces, which may occur for PAO-based calculations if one is not

  20. Digital module for neutron flux measurement by Campbell method

    International Nuclear Information System (INIS)

    Baratte, G.

    1987-02-01

    The study reported here concerns a wide range measurement channel for reactor control instrumentation but it may also be useful for specific measurements requiring the Campbell method. A wide range measurement channel allows the processing of the signal issued from a single fission chamber so it's possible to insure control of nuclear reactors in three different running modes: pulse processing, fluctuations and current. The study described in this note includes three parts: - the analogical wide range neutron measurement channel is presented in the first chapter; the fluctuation mode is thoroughly studied; the results of tests and proper limitations of analogical processing are summarized. A theoretical study of the neutron flux measurement by numerical calculation of the fluctuation signal variance is given in the second chapter. The digital module is described in the third chapter; the results of experiments are analysed. The validity of the digital method is proved by means of a practical realisation. The performances obtained with the digital fluctuation test model may be compared with those given by the analogical fluctuation channel which can be used for the control of lower fission rates. The digital module may also be used for any fluctuation measurement where very short response time and broad spectral band of analysis are not strictly necessary [fr

  1. Employing airborne multispectral digital imagery to map Brazilian pepper infestation in south Texas.

    Science.gov (United States)

    A study was conducted in south Texas to determine the feasibility of using airborne multispectral digital imagery for differentiating the invasive plant Brazilian pepper (Schinus terebinthifolius) from other cover types. Imagery obtained in the visible, near infrared, and mid infrared regions of th...

  2. Finite element formulation for a digital image correlation method

    International Nuclear Information System (INIS)

    Sun Yaofeng; Pang, John H. L.; Wong, Chee Khuen; Su Fei

    2005-01-01

    A finite element formulation for a digital image correlation method is presented that will determine directly the complete, two-dimensional displacement field during the image correlation process on digital images. The entire interested image area is discretized into finite elements that are involved in the common image correlation process by use of our algorithms. This image correlation method with finite element formulation has an advantage over subset-based image correlation methods because it satisfies the requirements of displacement continuity and derivative continuity among elements on images. Numerical studies and a real experiment are used to verify the proposed formulation. Results have shown that the image correlation with the finite element formulation is computationally efficient, accurate, and robust

  3. Digital processing method for monitoring the radioactivity of stack releases

    International Nuclear Information System (INIS)

    Vialettes, H.; Leblanc, P.; Perotin, J.P.; Lazou, J.P.

    1978-01-01

    The digital processing method proposed is adapted for data supplied by a fixed-filter detector normally used for analogue processing (integrator system). On the basis of the raw data (pulses) from the detector, the technique makes it possible to determine the rate of activity released whereas analogue processing gives only the released activity. Furthermore, the method can be used to develop alarm systems on the basis of a possible exposure rate at the point of fall-out, and by including in the program a coefficient which allows for atmospheric diffusion conditions at any given time one can improve the accuracy of the results. In order to test the digital processing method and demonstrate its advantages over analogue processing, various atmospheric contamination situations were simulated in a glove-box and analysed simultaneously, using both systems, from the pulses transmitted by the same sampling and fixed-filter detection unit. The experimental results confirm the advantages foreseen in the theoretical research. (author)

  4. A digital method for period measurements in a nuclear reactor

    International Nuclear Information System (INIS)

    Mundim, Sergio Gorretta

    1971-02-01

    The present paper begins by giving a theoretical treatment for the nuclear reactor period. The conventional method of measuring the period is analysed and some previously developed digital methods are described. The paper criticises the latter, pointing out some deficiencies which the proposed process is able to eliminate. All errors connected with this process are also analysed. The paper presents suitable solutions to reduce them to a minimum. The total error is found to he less than the error presented by the other methods described. A digital period meter is designed with memory resources and an automatic scaler changer. Integrated circuits specifications are used in it. Real time experiments with nuclear reactors were made in order to check te validity of the method. The data acquired were applied to a simulated digital period meter implemented in a general purpose computer. The nuclear part of the work was developed at the 'Comissao Nacional de Energia Nuclear' and the simulation work was dane at the 'Departamento de Calculo Cientifico' of COPPE, which also advised the author in the completion of this thesis. (author)

  5. 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.

  6. Digital recording as a teaching and learning method in the skills laboratory.

    Science.gov (United States)

    Strand, Ingebjørg; Gulbrandsen, Lise; Slettebø, Åshild; Nåden, Dagfinn

    2017-09-01

    To obtain information on how nursing students react to, think about and learn from digital recording as a learning and teaching method over time. Based on the teaching and learning philosophy of the university college, we used digital recording as a tool in our daily sessions in skills laboratory. However, most of the studies referred to in the background review had a duration of from only a few hours to a number of days. We found it valuable to design a study with a duration of two academic semesters. A descriptive and interpretative design was used. First-year bachelor-level students at the department of nursing participated in the study. Data collection was carried out by employing an 'online questionnaire'. The students answered five written, open-ended questions after each of three practical skill sessions. Kvale and Brinkmann's three levels of understanding were employed in the analysis. The students reported that digital recording affected factors such as feeling safe, secure and confident and that video recording was essential in learning and training practical skills. The use of cameras proved to be useful, as an expressive tool for peer learning because video recording enhances self-assessment, reflection, sensing, psychomotor performance and discovery learning. Digital recording enhances the student's awareness when acquiring new knowledge because it activates cognitive and emotional learning. The connection between tutoring, feedback and technology was clear. The digital recorder gives students direct and immediate feedback on their performance from the various practical procedures, and may aid in the transition from theory to practice. Students experienced more self-confidence and a feeling of safety in their performances. © 2016 John Wiley & Sons Ltd.

  7. An Alternative to EPA Method 9 -- Field Validation of the Digital Opacity Compliance System (DOCS)

    National Research Council Canada - National Science Library

    Rasmussen, Steve L; Stone, Daniel A

    2005-01-01

    The Digital Opacity Compliance System (DOCS) software translates images from a commercial digital camera into visual plume opacity measurements, and is proposed as an alternate reporting method to EPA Method 9...

  8. A Hybrid Soft-computing Method for Image Analysis of Digital Plantar Scanners

    Science.gov (United States)

    Razjouyan, Javad; Khayat, Omid; Siahi, Mehdi; Mansouri, Ali Alizadeh

    2013-01-01

    Digital foot scanners have been developed in recent years to yield anthropometrists digital image of insole with pressure distribution and anthropometric information. In this paper, a hybrid algorithm containing gray level spatial correlation (GLSC) histogram and Shanbag entropy is presented for analysis of scanned foot images. An evolutionary algorithm is also employed to find the optimum parameters of GLSC and transform function of the membership values. Resulting binary images as the thresholded images are undergone anthropometric measurements taking in to account the scale factor of pixel size to metric scale. The proposed method is finally applied to plantar images obtained through scanning feet of randomly selected subjects by a foot scanner system as our experimental setup described in the paper. Running computation time and the effects of GLSC parameters are investigated in the simulation results. PMID:24083133

  9. A Hybrid Soft-computing Method for Image Analysis of Digital Plantar Scanners.

    Science.gov (United States)

    Razjouyan, Javad; Khayat, Omid; Siahi, Mehdi; Mansouri, Ali Alizadeh

    2013-01-01

    Digital foot scanners have been developed in recent years to yield anthropometrists digital image of insole with pressure distribution and anthropometric information. In this paper, a hybrid algorithm containing gray level spatial correlation (GLSC) histogram and Shanbag entropy is presented for analysis of scanned foot images. An evolutionary algorithm is also employed to find the optimum parameters of GLSC and transform function of the membership values. Resulting binary images as the thresholded images are undergone anthropometric measurements taking in to account the scale factor of pixel size to metric scale. The proposed method is finally applied to plantar images obtained through scanning feet of randomly selected subjects by a foot scanner system as our experimental setup described in the paper. Running computation time and the effects of GLSC parameters are investigated in the simulation results.

  10. A wideband CMOS inductorless low noise amplifier employing noise cancellation for digital TV tuner applications

    International Nuclear Information System (INIS)

    Zhang Jihong; Bai Xuefei; Huang Lu

    2013-01-01

    A wideband inductorless low noise amplifier for digital TV tuner applications is presented. The proposed LNA scheme uses a composite NMOS/PMOS cross-coupled transistor pair to provide partial cancellation of noise generated by the input transistors. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed LNA achieves 12.2–15.2 dB voltage gain from 300 to 900 MHz, the noise figure is below 3.1 dB and has a minimum value of 2.3 dB, and the best input-referred 1-dB compression point (IP1dB) is − 17 dBm at 900 MHz. The core consumes 7 mA current with a supply voltage of 1.8 V and occupies an area of 0.5 × 0.35 mm 2 . (semiconductor integrated circuits)

  11. Decorative design of ceramic tiles adapted to inkjet printing employing digital image processing

    International Nuclear Information System (INIS)

    Defez, B.; Santiago-Praderas, V.; Lluna, E.; Peris-Fajarnes, G.; Dunai, E.

    2013-01-01

    The ceramic tile sector is a very competitive industry. The designer's proficiency to offer new models of the decorated surface, adapted to the production means, plays a very important role in the competitiveness. In the present work, we analyze the evolution of the design process in the ceramic sector, as much as the changes experimented in parallel by the printing equipment. Afterwards, we present a new concept of ceramic design, based on digital image processing. This technique allows the generation of homogeneous and non-repetitive designs for large surfaces, especially thought for inkjet printing. With the programmed algorithms we have compiled a prototype software for the assistance of the ceramic design. This tool allows creating continuous designs for large surfaces saving developing time. (Author)

  12. Digital Technology in Adolescent s Employability: challenges and possibilities in current education

    OpenAIRE

    Bolfe, Marcelo

    2011-01-01

    A presente dissertação tem como objetivo analisar a importância da tecnologia digital na inserção de jovens no mundo do trabalho. A discussão e análise desta pesquisa se dá por meio da preocupação com a capacitação e as estratégias para oferecer acesso a tecnologias e conhecimentos aos jovens, como forma de melhor prepará-los para sua inserção no mundo do trabalho. Optou-se por uma pesquisa de campo, de caráter quanti-qualitativo, utilizando como instrumento de pesquisa um questionário semies...

  13. Evaluating two methods of digital photography in retinopathy screening

    Directory of Open Access Journals (Sweden)

    Li Chen

    2018-02-01

    Full Text Available AIM:To evaluate the advantages of non-mydriatic fundus photography(NMFCSand mydriatic fundus photography(MFCSas eye-bottom screening and diagnosis methods in compared with gold standard fluorescein fundus angiography(FFA. METHODS: A total of 276 patients which involved in Chronic Diabetes Management Achieves within 4 streets of Pudong District Shanghai, were enrolled for diabetic retinopathy(DRexamination including NMFCS, MFCS and FFA. These DR examinations were proceeded after vision, slit-lamp and dioptroscopy tests, and reported by professionals. For those with suspicious fundus diseases, we would make appointments with specialist for further treatment. RESULTS: A total of 1104 colorful fundus images, and 1056 images(95.65%could be used to analyze. There were 408 appreciable images, 116 basically appreciable images and 28 unusable images in 552 NMFCS images. In addition, there were 432 appreciable images, 100 basically appreciable images and 20 unusable images in 552 MFCS images. There was no significant differences between NMFCS and MFCS(P>0.05. Compared with FFA with DRⅠ as the critical value, the specificity of digital photography for NMFCS was 95.71%, the sensitivity was 93.56%; however, MFCS are 95.43% and 98.02%. There was no statistically significant difference between the two screening methods(P>0.05. Compared with FFA with DRⅡ as the critical value, the specificity of digital photography for NMFCS was 95.35% and the sensitivity was 93.44%; however, for MFCS were 95.81% and 98.36%. There was no statistically significant difference between the two screening methods(P>0.05. CONCLUSION: Both NMFCS and MFCS could be used for the diagnosis and screening for eye diseases. NMFCS is easier and faster for digital photography, which is suitable for mass screening. MFCS is more likely to provide detailed information about the follow-up of the disease.

  14. Methods of alleviation of ionospheric scintillation effects on digital communications

    Science.gov (United States)

    Massey, J. L.

    1974-01-01

    The degradation of the performance of digital communication systems because of ionospheric scintillation effects can be reduced either by diversity techniques or by coding. The effectiveness of traditional space-diversity, frequency-diversity and time-diversity techniques is reviewed and design considerations isolated. Time-diversity signaling is then treated as an extremely simple form of coding. More advanced coding methods, such as diffuse threshold decoding and burst-trapping decoding, which appear attractive in combatting scintillation effects are discussed and design considerations noted. Finally, adaptive coding techniques appropriate when the general state of the channel is known are discussed.

  15. 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...

  16. Methods employed in the prevention and treatment of malaria ...

    African Journals Online (AJOL)

    onasoga olayinka

    of malaria among pregnant women in riverine community in Bayelsa State, ... at high risk of the effects of malaria infection and need special protective .... mentioned maintenance of clean environment, as other methods of preventing malaria.

  17. Dental age estimation using Willems method: A digital orthopantomographic study

    Directory of Open Access Journals (Sweden)

    Rezwana Begum Mohammed

    2014-01-01

    Full Text Available In recent years, age estimation has become increasingly important in living people for a variety of reasons, including identifying criminal and legal responsibility, and for many other social events such as a birth certificate, marriage, beginning a job, joining the army, and retirement. Objectives: The aim of this study was to assess the developmental stages of left seven mandibular teeth for estimation of dental age (DA in different age groups and to evaluate the possible correlation between DA and chronological age (CA in South Indian population using Willems method. Materials and Methods: Digital Orthopantomogram of 332 subjects (166 males, 166 females who fit the study and the criteria were obtained. Assessment of mandibular teeth (from central incisor to the second molar on left quadrant development was undertaken and DA was assessed using Willems method. Results and Discussion: The present study showed a significant correlation between DA and CA in both males (r = 0.71 and females (r = 0.88. The overall mean difference between the estimated DA and CA for males was 0.69 ± 2.14 years (P 0.05. Willems method underestimated the mean age of males by 0.69 years and females by 0.08 years and showed that females mature earlier than males in selected population. The mean difference between DA and CA according to Willems method was 0.39 years and is statistically significant (P < 0.05. Conclusion: This study showed significant relation between DA and CA. Thus, digital radiographic assessment of mandibular teeth development can be used to generate mean DA using Willems method and also the estimated age range for an individual of unknown CA.

  18. Research methods of simulate digital compensators and autonomous control systems

    Directory of Open Access Journals (Sweden)

    V. S. Kudryashov

    2016-01-01

    Full Text Available The peculiarity of the present stage of development of the production is the need to control and regulate a large number of process parameters, the mutual influence on each other that when using single-circuit systems significantly reduces the quality of the transition process, resulting in significant costs of raw materials and energy, reduce the quality of the products. Using a stand-alone digital control system eliminates the correlation of technological parameters, to give the system the desired dynamic and static properties, improve the quality of regulation. However, the complexity of the configuration and implementation of procedures (modeling compensators autonomous systems of this type, associated with the need to perform a significant amount of complex analytic transformation significantly limit the scope of their application. In this regard, the approach based on the decompo sition proposed methods of calculation and simulation (realization, consisting in submitting elements autonomous control part digital control system in a series parallel connection. The above theoretical study carried out in a general way for any dimension systems. The results of computational experiments, obtained during the simulation of the four autonomous control systems, comparative analysis and conclusions on the effectiveness of the use of each of the methods. The results obtained can be used in the development of multi-dimensional process control systems.

  19. High frequency, high time resolution time-to-digital converter employing passive resonating circuits.

    Science.gov (United States)

    Ripamonti, Giancarlo; Abba, Andrea; Geraci, Angelo

    2010-05-01

    A method for measuring time intervals accurate to the picosecond range is based on phase measurements of oscillating waveforms synchronous with their beginning and/or end. The oscillation is generated by triggering an LC resonant circuit, whose capacitance is precharged. By using high Q resonators and a final active quenching of the oscillation, it is possible to conjugate high time resolution and a small measurement time, which allows a high measurement rate. Methods for fast analysis of the data are considered and discussed with reference to computing resource requirements, speed, and accuracy. Experimental tests show the feasibility of the method and a time accuracy better than 4 ps rms. Methods aimed at further reducing hardware resources are finally discussed.

  20. High frequency, high time resolution time-to-digital converter employing passive resonating circuits

    International Nuclear Information System (INIS)

    Ripamonti, Giancarlo; Abba, Andrea; Geraci, Angelo

    2010-01-01

    A method for measuring time intervals accurate to the picosecond range is based on phase measurements of oscillating waveforms synchronous with their beginning and/or end. The oscillation is generated by triggering an LC resonant circuit, whose capacitance is precharged. By using high Q resonators and a final active quenching of the oscillation, it is possible to conjugate high time resolution and a small measurement time, which allows a high measurement rate. Methods for fast analysis of the data are considered and discussed with reference to computing resource requirements, speed, and accuracy. Experimental tests show the feasibility of the method and a time accuracy better than 4 ps rms. Methods aimed at further reducing hardware resources are finally discussed.

  1. Methods employed to speed up Cathare for simulation uses

    International Nuclear Information System (INIS)

    Agator, J.M.

    1992-01-01

    This paper describes the main methods used to speed up the french advanced thermal-hydraulic computer code CATHARE and build a speedy version, called CATHARE-SIMU, adapted to real time calculations and simulation environment. Since CATHARE-SIMU, like CATHARE, uses a numerical scheme based on a fully implicit Newton's iterative method, and therefore with a variable time step, two ways have been explored to reduce the computing time: avoidance of short time steps, and so minimization of the number of iterations per time step, reduction of the computing time needed for an iteration. CATHARE-SIMU uses the same physical laws and correlations as in CATHARE with only some minor simplifications. This was considered the only way to be sure to maintain the level of physical relevance of CATHARE. Finally it is indicated that the validation programme of CATHARE-SIMU includes a set of 33 transient calculations, referring either to CATHARE for two-phase transients, or to measurements on real plants for operational transients

  2. Who Gets the Job? First-Generation College Students' Perceptions of Employer Screening Methods

    Science.gov (United States)

    Parks-Yancy, Rochelle; Cooley, Delonia

    2018-01-01

    What are first-generation college students' (FGCS) perspectives of employment screening methods? The authors investigate which methods FGCS believe are likely to cause an employer to extend a job offer and which methods yield the best pool of job applicants. Survey data were collected from undergraduate business majors. They were analyzed using…

  3. Employing Machine-Learning Methods to Study Young Stellar Objects

    Science.gov (United States)

    Moore, Nicholas

    2018-01-01

    Vast amounts of data exist in the astronomical data archives, and yet a large number of sources remain unclassified. We developed a multi-wavelength pipeline to classify infrared sources. The pipeline uses supervised machine learning methods to classify objects into the appropriate categories. The program is fed data that is already classified to train it, and is then applied to unknown catalogues. The primary use for such a pipeline is the rapid classification and cataloging of data that would take a much longer time to classify otherwise. While our primary goal is to study young stellar objects (YSOs), the applications extend beyond the scope of this project. We present preliminary results from our analysis and discuss future applications.

  4. A digital image method of spot tests for determination of copper in sugar cane spirits

    Science.gov (United States)

    Pessoa, Kenia Dias; Suarez, Willian Toito; dos Reis, Marina Ferreira; de Oliveira Krambeck Franco, Mathews; Moreira, Renata Pereira Lopes; dos Santos, Vagner Bezerra

    2017-10-01

    In this work the development and validation of analytical methodology for determination of copper in sugarcane spirit samples is carried out. The digital image based (DIB) method was applied along with spot test from the colorimetric reaction employing the RGB color model. For the determination of copper concentration, it was used the cuprizone - a bidentate organic reagent - which forms with copper a blue chelate in an alkaline medium. A linear calibration curve over the concentration range from 0.75 to 5.00 mg L- 1 (r2 = 0.9988) was obtained and limits of detection and quantification of 0.078 mg L- 1 and 0.26 mg L- 1 were acquired, respectively. For the accuracy studies, recovery percentages ranged from 98 to 104% were obtained. The comparison of cooper concentration results in sugar cane spirits using the DIB method and Flame Atomic Absorption Spectrometry as reference method showed no significant differences between both methods, which were performed using the paired t-test in 95% of confidence level. Thus, the spot test method associated with DIB allows the use of devices as digital cameras and smartphones to evaluate colorimetric reaction with low waste generation, practicality, quickness, accuracy, precision, high portability and low-cost.

  5. Enterprise’s employment potential: concept, components and evaluation methods

    Directory of Open Access Journals (Sweden)

    Korbut K.Ye.

    2017-06-01

    Full Text Available The present study deals with the main interpretations and views of scientists on the economic category «labor potential». The conditions and factors affecting the labor potential are given. The author makes the classification and provides the general characteristic to the factors, which characterize the mechanism of formation of the labor potential. The detailed description of the main components and the components of the labor potential at the enterprise has been determined, analyzed and provided. The levels of the labor potential manifestation are summarized, and examined, and the explanation is given to each of them. The general characteristic of the constituent elements of workers’ labor potential is provided. The principal data of the labor potential at the micro level are provided. The main types of the labor potential at the enterprise are singled out and characterized in detail by the level of aggregated estimates, by the range of coverage of opportunities, by the nature of participation in the production and economic process and by the place in the socio-economic system of the enterprise. Considerable attention is paid to the views of scientists on the main methods of assessing the labor potential of the enterprise.

  6. Method of simulating dose reduction for digital radiographic systems

    International Nuclear Information System (INIS)

    Baath, M.; Haakansson, M.; Tingberg, A.; Maansson, L. G.

    2005-01-01

    The optimisation of image quality vs. radiation dose is an important task in medical imaging. To obtain maximum validity of the optimisation, it must be based on clinical images. Images at different dose levels can then either be obtained by collecting patient images at the different dose levels sought to investigate - including additional exposures and permission from an ethical committee - or by manipulating images to simulate different dose levels. The aim of the present work was to develop a method of simulating dose reduction for digital radiographic systems. The method uses information about the detective quantum efficiency and noise power spectrum at the original and simulated dose levels to create an image containing filtered noise. When added to the original image this results in an image with noise which, in terms of frequency content, agrees with the noise present in an image collected at the simulated dose level. To increase the validity, the method takes local dose variations in the original image into account. The method was tested on a computed radiography system and was shown to produce images with noise behaviour similar to that of images actually collected at the simulated dose levels. The method can, therefore, be used to modify an image collected at one dose level so that it simulates an image of the same object collected at any lower dose level. (authors)

  7. Research on Splicing Method of Digital Relic Fragment Model

    Science.gov (United States)

    Yan, X.; Hu, Y.; Hou, M.

    2018-04-01

    In the course of archaeological excavation, a large number of pieces of cultural relics were unearthed, and the restoration of these fragments was done manually by traditional arts and crafts experts. In this process, cultural relics experts often try to splice the existing cultural relics, and then use adhesive to stick together the fragments of correct location, which will cause irreversible secondary damage to cultural relics. In order to minimize such damage, the surveyors combine 3D laser scanning with computer technology, and use the method of establishing digital cultural relics fragments model to make virtual splicing of cultural relics. The 3D software on the common market can basically achieve the model translation and rotation, using this two functions can be achieved manually splicing between models, mosaic records after the completion of the specific location of each piece of fragments, so as to effectively reduce the damage to the relics had tried splicing process.

  8. Digital integrated protection system: Quantitative methods for dependability evaluation

    International Nuclear Information System (INIS)

    Krotoff, H.; Benski, C.

    1986-01-01

    The inclusion of programmed digital techniques in the SPIN system provides the used with the capability of performing sophisticated processing operations. However, it causes the quantitative evaluation of the overall failure probabilities to become somewhat more intricate by reason that: A single component may be involved in several functions; Self-tests may readily be incorporated for the purpose of monitoring the dependable operation of the equipment at all times. This paper describes the methods as implemented by MERLIN GERIN for the purpose of evaluating: The probabilities for the protective actions not to be initiated (dangerous failures); The probabilities for such protective actions to be initiated accidentally. Although the communication is focused on the programmed portion of the SPIN (UAIP) it will also deal with the evaluation performed within the scope of study works that do not exclusively cover the UAIPs

  9. A New Digital Signal Processing Method for Spectrum Interference Monitoring

    Science.gov (United States)

    Angrisani, L.; Capriglione, D.; Ferrigno, L.; Miele, G.

    2011-01-01

    Frequency spectrum is a limited shared resource, nowadays interested by an ever growing number of different applications. Generally, the companies providing such services pay to the governments the right of using a limited portion of the spectrum, consequently they would be assured that the licensed radio spectrum resource is not interested by significant external interferences. At the same time, they have to guarantee that their devices make an efficient use of the spectrum and meet the electromagnetic compatibility regulations. Therefore the competent authorities are called to control the access to the spectrum adopting suitable management and monitoring policies, as well as the manufacturers have to periodically verify the correct working of their apparatuses. Several measurement solutions are present on the market. They generally refer to real-time spectrum analyzers and measurement receivers. Both of them are characterized by good metrological accuracies but show costs, dimensions and weights that make no possible a use "on the field". The paper presents a first step in realizing a digital signal processing based measurement instrument able to suitably accomplish for the above mentioned needs. In particular the attention has been given to the DSP based measurement section of the instrument. To these aims an innovative measurement method for spectrum monitoring and management is proposed in this paper. It performs an efficient sequential analysis based on a sample by sample digital processing. Three main issues are in particular pursued: (i) measurement performance comparable to that exhibited by other methods proposed in literature; (ii) fast measurement time, (iii) easy implementation on cost-effective measurement hardware.

  10. Simple method of modelling of digital holograms registering and their optical reconstruction

    International Nuclear Information System (INIS)

    Evtikhiev, N N; Cheremkhin, P A; Krasnov, V V; Kurbatova, E A; Molodtsov, D Yu; Porshneva, L A; Rodin, V G

    2016-01-01

    The technique of modeling of digital hologram recording and image optical reconstruction from these holograms is described. The method takes into account characteristics of the object, digital camera's photosensor and spatial light modulator used for digital holograms displaying. Using the technique, equipment can be chosen for experiments for obtaining good reconstruction quality and/or holograms diffraction efficiency. Numerical experiments were conducted. (paper)

  11. Digital Storytelling: A Method for Engaging Students and Increasing Cultural Competency

    Science.gov (United States)

    Grant, Natalie S.; Bolin, Brien L.

    2016-01-01

    Digital storytelling is explored as a method of engaging students in the development of media literacy and cultural competency. This paper describes the perceptions and experiences of 96 undergraduate students at a large Midwestern university, after completing a digital storytelling project in a semester-long diversity course. Digital storytelling…

  12. Measuring Digital Signage ROI : A combination of Digital Signage and Mobile Advertising as a method for measuring Digtal Signage ROI

    OpenAIRE

    Helander, Fredrik

    2010-01-01

    Marketing has changed a lot the past decade. New modern marketing channels have been developed and marketing have become more effective. This has affected the expectations advertisers have on advertising channels. One thing advertisers increasingly expect is to be able to efficiently measure the result of advertising, the ROI. A method for measuring ROI of digital signage is in focus in this study. The measurement is enabled by a combination of digital signage and mobile advertising. First a ...

  13. 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

  14. Evaluating ranking methods on heterogeneous digital library collections

    CERN Document Server

    Canévet, Olivier; Marian, Ludmila; Chonavel, Thierry

    In the frame of research in particle physics, CERN has been developing its own web-based software /Invenio/ to run the digital library of all the documents related to CERN and fundamental physics. The documents (articles, photos, news, thesis, ...) can be retrieved through a search engine. The results matching the query of the user can be displayed in several ways: sorted by latest first, author, title and also ranked by word similarity. The purpose of this project is to study and implement a new ranking method in Invenio: distributed-ranking (D-Rank). This method aims at aggregating several ranking scores coming from different ranking methods into a new score. In addition to query-related scores such as word similarity, the goal of the work is to take into account non-query-related scores such as citations, journal impact factor and in particular scores related to the document access frequency in the database. The idea is that for two equally query-relevant documents, if one has been more downloaded for inst...

  15. Geometric estimation method for x-ray digital intraoral tomosynthesis

    Science.gov (United States)

    Li, Liang; Yang, Yao; Chen, Zhiqiang

    2016-06-01

    It is essential for accurate image reconstruction to obtain a set of parameters that describes the x-ray scanning geometry. A geometric estimation method is presented for x-ray digital intraoral tomosynthesis (DIT) in which the detector remains stationary while the x-ray source rotates. The main idea is to estimate the three-dimensional (3-D) coordinates of each shot position using at least two small opaque balls adhering to the detector surface as the positioning markers. From the radiographs containing these balls, the position of each x-ray focal spot can be calculated independently relative to the detector center no matter what kind of scanning trajectory is used. A 3-D phantom which roughly simulates DIT was designed to evaluate the performance of this method both quantitatively and qualitatively in the sense of mean square error and structural similarity. Results are also presented for real data acquired with a DIT experimental system. These results prove the validity of this geometric estimation method.

  16. Employed and unemployed job search methods: Australian evidence on search duration, wages and job stability

    OpenAIRE

    Colin Green

    2012-01-01

    This paper examines the use and impact of job search methods of both unemployed and employed job seekers. Informal job search methods are associated with relativel high level of job exit and shorter search duration. Job exists through the public employment agency (PEA) display positive duration dependence for the unemployed. This may suggest that the PEA is used as a job search method of last resort. Informal job search methods have lower associated duration in search and higher wages than th...

  17. A simple method of digitizing analog scintigrams for quantification and digital archiving. Eine einfache Methode der Digitalisierung von Analogszintigrammen zur Quantifizierung und digitalen Archivierung

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, M. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany)); Kaempfer, B. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany)); Wolf, H. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany)); Clausen, M. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany)); Wendhausen, H. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany)); Henze, E. (Klinik fuer Nuklearmedizin, Kiel Univ. (Germany))

    1993-02-01

    This study was undertaken to evaluate a quick, reliable and cheap method of digitizing analog scintigrams. 40 whole-body bone scintigrams were obtained simultaneously in analog and genuine digital format. The analog scans on X-ray film were then digitized seecondarily by three different methods: 300 dpi flatbed scanning, high-resolution camera scanning and camcorder recording. A simple exposure approach using a light box, a cheap camcorder, a PC and image grabber hard- and software proved to be optimal. Visual interpretation showed no differences in clinical findings when comparing the analog images with their secondarily digitized counterparts. To test the possibility of quantification, 126 equivalent ROIs were drawn both in the genuine digital and the secondarily digitized images. Comparing the ROI count to whole-body count percentage of the corresponding ROIs showed the correlation to be linear. The evaluation of phantom studies showed the linear correlation to be true within a wide activity range. Thus, secondary digitalization of analog scintigrams is an easy, cheap and reliable method of archiving images and allows secondary digital quantification. (orig.)

  18. 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...

  19. Repurposing digital methods: The research affordances of platforms and engines

    NARCIS (Netherlands)

    Weltevrede, E.J.T.

    2016-01-01

    Digital research is often understood as data-driven. Yet the ways in which data are already informed by specific analytical assumptions and inscriptions of the media in which they originate, circulate, or are being used is often neglected. The thesis intervenes in such focus on digital research in

  20. A Method to Identify Flight Obstacles on Digital Surface Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; LIN Xinggang; SUN Shouyu; WANG Youzhi

    2005-01-01

    In modern low-altitude terrain-following guidance, a constructing method of the digital surface model (DSM) is presented in the paper to reduce the threat to flying vehicles of tall surface features for safe flight. The relationship between an isolated obstacle size and the intervals of vertical- and cross-section in the DSM model is established. The definition and classification of isolated obstacles are proposed, and a method for determining such isolated obstacles in the DSM model is given. The simulation of a typical urban district shows that when the vertical- and cross-section DSM intervals are between 3 m and 25 m, the threat to terrain-following flight at low-altitude is reduced greatly, and the amount of data required by the DSM model for monitoring in real time a flying vehicle is also smaller. Experiments show that the optimal results are for an interval of 12.5 m in the vertical- and cross-sections in the DSM model, with a 1:10 000 DSM scale grade.

  1. A study of digital hardware architectures for nuclear reactors protection systems applications - reliability and safety analysis methods

    International Nuclear Information System (INIS)

    Benko, Pedro Luiz

    1997-01-01

    A study of digital hardware architectures, including experience in many countries, topologies and solutions to interface circuits for protection systems of nuclear reactors is presented. Methods for developing digital systems architectures based on fault tolerant and safety requirements is proposed. Directives for assessing such conditions are suggested. Techniques and the most common tools employed in reliability, safety evaluation and modeling of hardware architectures is also presented. Markov chain modeling is used to evaluate the reliability of redundant architectures. In order to estimate software quality, several mechanisms to be used in design, specification, and validation and verification (V and V) procedures are suggested. A digital protection system architecture has been analyzed as a case study. (author)

  2. Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

    OpenAIRE

    Kuang Tsan Lin; Sheng Lih Yeh

    2014-01-01

    The Rivest-Shamir-Adleman (RSA) encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matri...

  3. 29 CFR 4010.12 - Alternative method of compliance for certain sponsors of multiple employer plans.

    Science.gov (United States)

    2010-07-01

    ... BENEFIT GUARANTY CORPORATION CERTAIN REPORTING AND DISCLOSURE REQUIREMENTS ANNUAL FINANCIAL AND ACTUARIAL INFORMATION REPORTING § 4010.12 Alternative method of compliance for certain sponsors of multiple employer... part for an information year if any contributing sponsor of the multiple employer plan provides a...

  4. Methods for monitoring work-life balance in a digital world

    OpenAIRE

    Chong, Ming Ki; Whittle, Jon; Rashid, Umar; Ang, Chee Siang; Whiting, Rebecca; Roby, Helen; Chamakiotis, Petros; Symon, Gillian

    2014-01-01

    Digital technologies - smart phones, email, social networking, etc. - are fundamentally changing our relationship with work. Digital technologies enable us to be always connected. However, the question remains as to how digital technologies affect our work-life balance. In this position paper, we report on some methods we are using to study how to continuously monitor and observe work-life balance, and discuss the advantages/disadvantages of these methods. Work-life balance is a relatively un...

  5. A peak value searching method of the MCA based on digital logic devices

    International Nuclear Information System (INIS)

    Sang Ziru; Huang Shanshan; Chen Lian; Jin Ge

    2010-01-01

    Digital multi-channel analyzers play a more important role in multi-channel pulse height analysis technique. The direction of digitalization are characterized by powerful pulse processing ability, high throughput, improved stability and flexibility. This paper introduces a method of searching peak value of waveform based on digital logic with FPGA. This method reduce the dead time. Then data correction offline can improvement the non-linearity of MCA. It gives the α energy spectrum of 241 Am. (authors)

  6. MACHINE LEARNING METHODS IN DIGITAL AGRICULTURE: ALGORITHMS AND CASES

    Directory of Open Access Journals (Sweden)

    Aleksandr Vasilyevich Koshkarov

    2018-05-01

    Full Text Available Ensuring food security is a major challenge in many countries. With a growing global population, the issues of improving the efficiency of agriculture have become most relevant. Farmers are looking for new ways to increase yields, and governments of different countries are developing new programs to support agriculture. This contributes to a more active implementation of digital technologies in agriculture, helping farmers to make better decisions, increase yields and take care of the environment. The central point is the collection and analysis of data. In the industry of agriculture, data can be collected from different sources and may contain useful patterns that identify potential problems or opportunities. Data should be analyzed using machine learning algorithms to extract useful insights. Such methods of precision farming allow the farmer to monitor individual parts of the field, optimize the consumption of water and chemicals, and identify problems quickly. Purpose: to make an overview of the machine learning algorithms used for data analysis in agriculture. Methodology: an overview of the relevant literature; a survey of farmers. Results: relevant algorithms of machine learning for the analysis of data in agriculture at various levels were identified: soil analysis (soil assessment, soil classification, soil fertility predictions, weather forecast (simulation of climate change, temperature and precipitation prediction, and analysis of vegetation (weed identification, vegetation classification, plant disease identification, crop forecasting. Practical implications: agriculture, crop production.

  7. Digital-data receiver synchronization method and apparatus

    Science.gov (United States)

    Smith, Stephen F [Loudon, TN; Turner, Gary W [Clinton, TN

    2009-09-08

    Digital data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  8. Method for evaluating operator inputs to digital controllers

    International Nuclear Information System (INIS)

    Venhuizen, J.R.

    1983-01-01

    Most industrial processes employ operator-interactive control systems. The performance of these control systems is influenced by the choice of control station (device through which operator enters control commands). While the importance of proper control-station selection is widely accepted, standard and simple selection methods are not available for the control station using color-graphics terminals. This paper describes a unique facility for evaluating the effectiveness of various control stations. In the facility, a process is simulated on a hybrid computer, color-graphics display terminals provide information to the operator, and different control stations accept input commands to control the simulation. Tests are being conducted to evaluate a keyboard, a graphics tablet, and a CRT touch panel for use as control stations on a nuclear power plant. Preliminary results indicate that our facility can be used to determine those situations where each type of station is advantageous

  9. Bispectral methods of signal processing applications in radar, telecommunications and digital image restoration

    CERN Document Server

    Totsky, Alexander V; Kravchenko, Victor F

    2015-01-01

    By studying applications in radar, telecommunications and digital image restoration, this monograph discusses signal processing techniques based on bispectral methods. Improved robustness against different forms of noise as well as preservation of phase information render this method a valuable alternative to common power-spectrum analysis used in radar object recognition, digital wireless communications, and jitter removal in images.

  10. Physical Principles of the Method for Determination of Geometrical Characteristics and Particle Recognition in Digital Holography

    Science.gov (United States)

    Dyomin, V. V.; Polovtsev, I. G.; Davydova, A. Yu.

    2018-03-01

    The physical principles of a method for determination of geometrical characteristics of particles and particle recognition based on the concepts of digital holography, followed by processing of the particle images reconstructed from the digital hologram, using the morphological parameter are reported. An example of application of this method for fast plankton particle recognition is given.

  11. Gamma ray spectroscopy employing divalent europium-doped alkaline earth halides and digital readout for accurate histogramming

    Science.gov (United States)

    Cherepy, Nerine Jane; Payne, Stephen Anthony; Drury, Owen B.; Sturm, Benjamin W.

    2016-02-09

    According to one embodiment, a scintillator radiation detector system includes a scintillator, and a processing device for processing pulse traces corresponding to light pulses from the scintillator, where the processing device is configured to: process each pulse trace over at least two temporal windows and to use pulse digitization to improve energy resolution of the system. According to another embodiment, a scintillator radiation detector system includes a processing device configured to: fit digitized scintillation waveforms to an algorithm, perform a direct integration of fit parameters, process multiple integration windows for each digitized scintillation waveform to determine a correction factor, and apply the correction factor to each digitized scintillation waveform.

  12. A New Method to Measure Crack Extension in Nuclear Graphite Based on Digital Image Correlation

    Directory of Open Access Journals (Sweden)

    Shigang Lai

    2017-01-01

    Full Text Available Graphite components, used as moderators, reflectors, and core-support structures in a High-Temperature Gas-Cooled Reactor, play an important role in the safety of the reactor. Specifically, they provide channels for the fuel elements, control rods, and coolant flow. Fracture is the main failure mode for graphite, and breaching of the above channels by crack extension will seriously threaten the safety of a reactor. In this paper, a new method based on digital image correlation (DIC is introduced for measuring crack extension in brittle materials. Cross-correlation of the displacements measured by DIC with a step function was employed to identify the advancing crack tip in a graphite beam specimen under three-point bending. The load-crack extension curve, which is required for analyzing the R-curve and tension softening behaviors, was obtained for this material. Furthermore, a sensitivity analysis of the threshold value employed for the cross-correlation parameter in the crack identification process was conducted. Finally, the results were verified using the finite element method.

  13. Generation and coherent detection of QPSK signal using a novel method of digital signal processing

    Science.gov (United States)

    Zhao, Yuan; Hu, Bingliang; He, Zhen-An; Xie, Wenjia; Gao, Xiaohui

    2018-02-01

    We demonstrate an optical quadrature phase-shift keying (QPSK) signal transmitter and an optical receiver for demodulating optical QPSK signal with homodyne detection and digital signal processing (DSP). DSP on the homodyne detection scheme is employed without locking the phase of the local oscillator (LO). In this paper, we present an extracting one-dimensional array of down-sampling method for reducing unwanted samples of constellation diagram measurement. Such a novel scheme embodies the following major advantages over the other conventional optical QPSK signal detection methods. First, this homodyne detection scheme does not need strict requirement on LO in comparison with linear optical sampling, such as having a flat spectral density and phase over the spectral support of the source under test. Second, the LabVIEW software is directly used for recovering the QPSK signal constellation without employing complex DSP circuit. Third, this scheme is applicable to multilevel modulation formats such as M-ary PSK and quadrature amplitude modulation (QAM) or higher speed signals by making minor changes.

  14. A Method and Support Tool for the Analysis of Human Error Hazards in Digital Devices

    International Nuclear Information System (INIS)

    Lee, Yong Hee; Kim, Seon Soo; Lee, Yong Hee

    2012-01-01

    In recent years, many nuclear power plants have adopted modern digital I and C technologies since they are expected to significantly improve their performance and safety. Modern digital technologies were expected to significantly improve both the economical efficiency and safety of nuclear power plants. However, the introduction of an advanced main control room (MCR) is accompanied with lots of changes in forms and features and differences through virtue of new digital devices. Many user-friendly displays and new features in digital devices are not enough to prevent human errors in nuclear power plants (NPPs). It may be an urgent to matter find the human errors potentials due to digital devices, and their detailed mechanisms. We can then consider them during the design of digital devices and their interfaces. The characteristics of digital technologies and devices may give many opportunities to the interface management, and can be integrated into a compact single workstation in an advanced MCR, such that workers can operate the plant with minimum burden under any operating condition. However, these devices may introduce new types of human errors, and thus we need a means to evaluate and prevent such errors, especially within digital devices for NPPs. This research suggests a new method named HEA-BIS (Human Error Analysis based on Interaction Segment) to confirm and detect human errors associated with digital devices. This method can be facilitated by support tools when used to ensure the safety when applying digital devices in NPPs

  15. Study on the system-level test method of digital metering in smart substation

    Science.gov (United States)

    Zhang, Xiang; Yang, Min; Hu, Juan; Li, Fuchao; Luo, Ruixi; Li, Jinsong; Ai, Bing

    2017-03-01

    Nowadays, the test methods of digital metering system in smart substation are used to test and evaluate the performance of a single device, but these methods can only effectively guarantee the accuracy and reliability of the measurement results of a digital metering device in a single run, it does not completely reflect the performance when each device constitutes a complete system. This paper introduced the shortages of the existing test methods. A system-level test method of digital metering in smart substation was proposed, and the feasibility of the method was proved by the actual test.

  16. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for digital radiographic (DR) test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice facilitates the interoperability of digital X-ray imaging equipment by specifying image data transfer and archival methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information object definitions, information modules and a ...

  17. The Employers' Perspective on Barriers and Facilitators to Employment of People with Intellectual Disability: A Differential Mixed-Method Approach

    Science.gov (United States)

    Kocman, Andreas; Fischer, Linda; Weber, Germain

    2018-01-01

    Background: Obtaining employment is among the most important ambitions of people with intellectual disability. Progress towards comprehensive inclusive employment is hampered by numerous barriers. Limited research is available on these barriers and strategies to overcome them. Method: A mixed method approach in a sample of 30 HR-managers was used…

  18. Methods of compression of digital holograms, based on 1-level wavelet transform

    International Nuclear Information System (INIS)

    Kurbatova, E A; Cheremkhin, P A; Evtikhiev, N N

    2016-01-01

    To reduce the size of memory required for storing information about 3D-scenes and to decrease the rate of hologram transmission, digital hologram compression can be used. Compression of digital holograms by wavelet transforms is among most powerful methods. In the paper the most popular wavelet transforms are considered and applied to the digital hologram compression. Obtained values of reconstruction quality and hologram's diffraction efficiencies are compared. (paper)

  19. Synthesis method from low-coherence digital holograms for improvement of image quality in holographic display.

    Science.gov (United States)

    Mori, Yutaka; Nomura, Takanori

    2013-06-01

    In holographic displays, it is undesirable to observe the speckle noises with the reconstructed images. A method for improvement of reconstructed image quality by synthesizing low-coherence digital holograms is proposed. It is possible to obtain speckleless reconstruction of holograms due to low-coherence digital holography. An image sensor records low-coherence digital holograms, and the holograms are synthesized by computational calculation. Two approaches, the threshold-processing and the picking-a-peak methods, are proposed in order to reduce random noise of low-coherence digital holograms. The reconstructed image quality by the proposed methods is compared with the case of high-coherence digital holography. Quantitative evaluation is given to confirm the proposed methods. In addition, the visual evaluation by 15 people is also shown.

  20. Comparison of the Efficacy and Duration of Three Different Methods of Digital Block

    Directory of Open Access Journals (Sweden)

    M Dehghani

    2007-07-01

    Full Text Available Introduction & Objective: Finger injuries are very common and majority of them can be treated under digital block anesthesia. Traditional digital block is one of the most commonly performed blocks performed by care providers in several medical fields. There are two other less known methods, transthecal (pulley block, in which local anesthesia is injected into the flexor tendon sheat that needs less volume of anesthesia and hasnot neurovascular complications and subcutaneous block in which local anesthesia is injected subcutaneously at the level of A1 pulley. This study aimed to compare the results of the three methods of digital block. Materials & Methods: A prospective randomized clinical trial was performed at Kashani hospital to compare the less known transthecal (pulley and subcutaneous methods with traditional digital block with regard to the length of anesthesia and need to another anesthetic method (due to insufficient anesthesia as a supplement. We divided 150 patients that were admitted to kashani hospital operating room due to finger injury, randomly, into three groups. In each group the patients were anesthetized by one of the three different methods. All blocks were performed by the same investigator. Data were analyzed by SPSS software using T test. Results: Mean length of anesthesia was 34.2 min’s in the transthecal digital block method and 34 min’s in the subcutaneous method and 33.8 min’s in the traditional digital block method. A repeat injection or local infiltration as a supplement was necessary in 5 instances (7 blocks in the traditional digital block method and 9 instances (11blocks in the subcutaneous method (p<0.05. Conclusion: Regarding fewer injections and less amount of lidocaine and no risk of damaging the neurovascular bundles and comparable length of anesthesia and no need to supplemental anesthesia, transthecal digital block is an appropriate alternative to traditional digital block and subcutaneous injection.

  1. Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

    Directory of Open Access Journals (Sweden)

    Kuang Tsan Lin

    2014-01-01

    Full Text Available The Rivest-Shamir-Adleman (RSA encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matrix holographic image contain seven groups of codes used for reconstructing the covert image. The seven groups of codes are identification codes, covert-image dimension codes, covert-image graylevel codes, pre-RSA bit number codes, RSA key codes, post-RSA bit number codes, and information codes. The reconstructed covert image derived from the dot-matrix holographic image and the original covert image are exactly the same.

  2. Teaching Critical Analytical Methods in the Digital Typography Classroom.

    Science.gov (United States)

    Gibson, Michael

    1997-01-01

    Describes a studio project designed to help students (1) utilize the digital environment to organize typography and images that represent the socio-political context their solutions were required to identify; and (2) explore the empirical variables that help readers to access and contemplate the content presented by their text. (PA)

  3. Application of digital image correlation method for analysing crack ...

    Indian Academy of Sciences (India)

    centrated strain by imitating the treatment of micro-cracks using the finite element ... water and moisture to penetrate the concrete leading to serious rust of the ... The correlations among various grey values of digital images are analysed for ...

  4. Design method for a digitally trimmable MOS transistor structure

    DEFF Research Database (Denmark)

    Ning, Feng; Bruun, Erik

    1996-01-01

    A digitally trimmable MOS transistor is a MOS transistor consisting of a drain, a source, and a main gate as well as several subgates. The transconductance of the transistor is tunabledigitally by means of connecting subgates either to the main gate or to the source terminal. In this paper, a sys...

  5. Employment of a noninvasive magnetic method for evaluation of gastrointestinal transit in rats

    Directory of Open Access Journals (Sweden)

    Quini Caio C

    2012-05-01

    Full Text Available Abstract AC Biosusceptometry (ACB was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy.

  6. Employment of a noninvasive magnetic method for evaluation of gastrointestinal transit in rats

    OpenAIRE

    Quini, Caio C; Américo, Madileine F; Corá, Luciana A; Calabresi, Marcos FF; Alvarez, Matheus; Oliveira, Ricardo B; Miranda, Jose Ricardo A

    2012-01-01

    AC Biosusceptometry (ACB) was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy. © 2012 Quin...

  7. Correction method of slit modulation transfer function on digital medical imaging system

    International Nuclear Information System (INIS)

    Kim, Jung Min; Jung, Hoi Woun; Min, Jung Whan; Im, Eon Kyung

    2006-01-01

    By using CR image pixel data, We examined the way how to calculate the MTF and digital characteristic curve. It can be changed to the text-file (Excel) from a pixel data which was printed with a digital x-ray equipment. In this place, We described the way how to figure out and correct the sharpness of a digital images of the MTF from FUJITA. Excel program was utilized to calculate from radiography of slit. Digital characteristic curve, Line Spread Function, Discrete Fourier Transform, Fast Fourier Transform digital specification curve, were indicated in regular sequence. A big advantage of this method, It can be understood easily and you can get results without costly program an without full knowledge of computer language. It shows many different values by using different correction methods. Therefore we need to be handy with appropriate correction method and we should try many experiments to get a precise MTF figures

  8. Characterization of ceramic materials - Some methods employed in quality control of nuclear fuels

    International Nuclear Information System (INIS)

    Cardoso, P.E.; Ferraz, W.B.; Lameiras, F.S.; Lopes, J.A.M.; Santos, A.M.M. dos; Ferreira, R.A.N.

    1986-01-01

    Measuring methods are presented for specific surface, density, open porosity and microstructure, such as bulk density of particles in form of nicrospheres, for characterization of ceramic materials used as nuclear fuels. Some of these methods are alternatives to those usually employed, and they present some advantages, such as economy, speed of execution, and accuracy. (Author) [pt

  9. Vibration based structural health monitoring in fibre reinforced composites employing the modal strain energy method

    NARCIS (Netherlands)

    Loendersloot, Richard; Ooijevaar, T.H.; Warnet, Laurent; Akkerman, Remko; de Boer, Andries; Meguid, S.A.; Gomes, J.F.S.

    2009-01-01

    The feasibility of a vibration based damage identification method is investigated. The Modal Strain Energy method is applied to a T–beam structure. The dynamic response of an intact structure and a damaged, delaminated structure is analysed employing a commercially available Finite Element package.

  10. Developing Employability Skills in Information System Graduates: Traditional vs. Innovative Teaching Methods

    Science.gov (United States)

    Osmani, Mohamad; Hindi, Nitham M.; Weerakkody, Vishanth

    2018-01-01

    It is widely acknowledged that traditional teaching methods such as lectures, textbooks and case study techniques on their own are not adequate to improving the most in-demand employability skills for graduates. The aim of this article is to explore the potential impact that novel learning and teaching methods can have on improving the…

  11. New methods for the investigation of phase objects by digital Speckle-pattern-interferometry

    International Nuclear Information System (INIS)

    Fliesser, W.

    1996-11-01

    This work shows new possibilities for spatially resolved interferometric investigations of transparent objects (phase-objects) applying the method of Digital-Speckle-Pattern-Interferometry (DSPI). A feedback-system using an additional MICHELSON-interferometer in the reference-arm of the Speckle-interferometer was installed for computer-controlled digitalization of the primary interferograms at defined phase-shifts. A special program for interferogram analysis allows the evaluation of two-dimensional phase distributions using different phase-stepping algorithms as 3-Frame-, 4-Frame-, CARRE-, 4+1-Frame- and 6+1-Frame technique. Special DSPI-setups with modified MACH-ZEHNDER-interferometers were used to check the system. In some basic experiments the temperature distribution in a cross section of convective heat-flows of air was measured. As an application on plasma-diagnostics the space-resolved electron density in a high pressure mercury lamp was determined using two-wavelength-DSPI. To increase the sensitivity of the method a Nd-YAG-laser at 1064 nm was employed in addition to an Ar + -laser at 488 Nm. The electron density in one cross-section of the lamp could be calculated by ABEL-inversion of the measured phase data. A multi-directional optical setup with a special mirror system was developed to investigate asymmetric phase-objects by DSPI. The setup allows to store six primary interferograms from different directions in one step, while using a single reference-beam only. Helium flows in air with different flow geometries were used as phase-objects. Tomographic reconstruction procedures such as the convolution-method yield the distributions of the refractive-index and the related helium concentrations in selected cross sections of the flow. (author)

  12. A survey of methods and practices used to stop digit sucking in 2-5 ...

    African Journals Online (AJOL)

    Conclusion: The findings from this study show that the most common method to stop digit sucking habit was the use of adhesive plaster. Negative practices included the use of razor blade to cut the digits and the application of bitter or peppery tasting substances. The use of appliances was not common and many mothers ...

  13. Interface Methods Renegotiating relations between digital social research, STS and the sociology

    NARCIS (Netherlands)

    Marres, N.; Gerlitz, C.

    2015-01-01

    This paper introduces a distinctive approach to methods development in digital social research called ‘interface methods’. We begin by discussing various methodological confluences between digital media, social studies of science and technology (STS) and sociology. Some authors have posited

  14. GHz wireless On-off-Keying link employing all photonic RF carrier generation and digital coherent detection

    DEFF Research Database (Denmark)

    Sambaraju, Rakesh; Zibar, Darko; Caballero Jambrina, Antonio

    2010-01-01

    Gb/s wireless signals at 82, 88 and 100 GHz carrier frequencies are successfully generated by heterodyne mixing of two optical carriers. A photonic detection technique with optical coherent receiver and digital signal processing is implemented for signal demodulation....

  15. Lesson learned - CGID based on the Method 1 and Method 2 for digital equipment

    International Nuclear Information System (INIS)

    Hwang, Wonil; Sohn, Kwang Young; Cho, Chang Hwan; Kim, Sung Jong

    2015-01-01

    The acceptance methods associated with commercial-grade dedication are the following: 1) Special tests and inspection (Method 1) 2) Commercial-grade surveys (Method 2) 3) Source verification (Method 3) 4) An acceptable item and supplier performance record (Method 4) Special tests and inspections, often referred to as Method 1, are performed by the dedicating entity after the item is received to verify selected critical characteristics. Conducting a commercial-grade survey of a supplier is often referred to as Method 2. Supplier audits to verify compliance with a nuclear QA program do not meet the intent of a commercial-grade survey. Source verification, often referred to as Method 3, entails verification of critical characteristics during manufacture and testing of the item being procured. The performance history (good or bad) of the item and supplier is a consideration when determining the use of the other acceptance methods and the rigor with which they are used on a case-by-case basis. Some digital equipment system has the delivery reference and its operating history for Nuclear Power Plant as far as surveyed. However it was found that there is difficulty in collecting this of supporting data sheet, so that supplier usually decide to conduct the CGID based on the Method-1 and Method-2 based on the initial qualification likely. It is conceived that the Method-4 might be a better approach for CGID(Commercial Grade Item Dedication) even if there are some difficulties in data package for justifying CGID from the vendor and operating organization. This paper present the lesson learned from the consulting for Method-1 and 2 for digital equipment dedication. Considering all the information above, there are a couple of issues to remind in order to perform the CGID for Method-2. In doing commercial grade survey based on Method 2, quality personnel as well as technical engineer shall be involved for integral dedication. Other than this, the review of critical

  16. Method for simulating dose reduction in digital mammography using the Anscombe transformation

    OpenAIRE

    Borges, Lucas R.; de Oliveira, Helder C. R.; Nunes, Polyana F.; Bakic, Predrag R.; Maidment, Andrew D. A.; Vieira, Marcelo A. C.

    2016-01-01

    Purpose: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. Methods: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the d...

  17. Evaluation of a digital method to assess evening meal intake in a free-living

    DEFF Research Database (Denmark)

    Lassen, Anne Dahl; Poulsen, Sanne; Andersen, Lotte Ernst

    2010-01-01

    Background: In recent years new applications of technologies, including digital images, to capture dietary behaviour in real time have been explored. Objectives: To validate a digital method for estimating evening meal intake in a free-living adult population, and to examine the feasibility...... of the method for recording evening meal intake over a prolonged period of time. Design: The digital method was compared against weighed records of 19 participants’ usual evening meals for five consecutive days. Two trained image analysts independently estimated the weight of individual foods within the meals...... estimation in real-time where a prolonged recording period of participants’ meals is needed....

  18. X-ray imaging using amorphous selenium: a photoinduced discharge readout method for digital mammography.

    Science.gov (United States)

    Rowlands, J A; Hunter, D M; Araj, N

    1991-01-01

    A new digital image readout method for electrostatic charge images on photoconductive plates is described. The method can be used to read out images on selenium plates similar to those used in xeromammography. The readout method, called the air-gap photoinduced discharge method (PID), discharges the latent image pixel by pixel and measures the charge. The PID readout method, like electrometer methods, is linear. However, the PID method permits much better resolution than scanning electrometers while maintaining quantum limited performance at high radiation exposure levels. Thus the air-gap PID method appears to be uniquely superior for high-resolution digital imaging tasks such as mammography.

  19. Correlation and agreement of a digital and conventional method to measure arch parameters.

    Science.gov (United States)

    Nawi, Nes; Mohamed, Alizae Marny; Marizan Nor, Murshida; Ashar, Nor Atika

    2018-01-01

    The aim of the present study was to determine the overall reliability and validity of arch parameters measured digitally compared to conventional measurement. A sample of 111 plaster study models of Down syndrome (DS) patients were digitized using a blue light three-dimensional (3D) scanner. Digital and manual measurements of defined parameters were performed using Geomagic analysis software (Geomagic Studio 2014 software, 3D Systems, Rock Hill, SC, USA) on digital models and with a digital calliper (Tuten, Germany) on plaster study models. Both measurements were repeated twice to validate the intraexaminer reliability based on intraclass correlation coefficients (ICCs) using the independent t test and Pearson's correlation, respectively. The Bland-Altman method of analysis was used to evaluate the agreement of the measurement between the digital and plaster models. No statistically significant differences (p > 0.05) were found between the manual and digital methods when measuring the arch width, arch length, and space analysis. In addition, all parameters showed a significant correlation coefficient (r ≥ 0.972; p digital and manual measurements. Furthermore, a positive agreement between digital and manual measurements of the arch width (90-96%), arch length and space analysis (95-99%) were also distinguished using the Bland-Altman method. These results demonstrate that 3D blue light scanning and measurement software are able to precisely produce 3D digital model and measure arch width, arch length, and space analysis. The 3D digital model is valid to be used in various clinical applications.

  20. 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

  1. Study on HRA-based method for assessing digital man-machine interface

    International Nuclear Information System (INIS)

    Li Pengcheng; Dai Licao; Zhang Li; Zhao Ming; Hu Hong

    2014-01-01

    In order to identify the design flaws of digital man-machine interface (MMI) that may trigger human errors or weaken the performance of operators, a HRA-based method (namely HCR + CREAM + HEC) for assessing digital MMI was established. Firstly, the HCR method was used to identify the risk scenarios of high human error probability from the overall event as a whole perspective. Then, for the identified high-risk scenarios, the CREAM was adopted to determine the various error modes and its error probability, and the failure probability was ranked. Finally, the human factors engineering checklist of digital MMI was established according to the characteristics of digital MMI, it was used to check the digital MMI with high error probability in order to identify the design flaws of digital MMI, and the suggestions of optimization were provided. The results show that the provided assessment method can quickly and efficiently identify the design flaws of digital MMI which easily trigger human errors, and the safety of operation of the digital control system for nuclear power plants can be enhanced by optimization of design. (authors)

  2. Valuing national effects of digital health investments: an applied method.

    Science.gov (United States)

    Hagens, Simon; Zelmer, Jennifer; Frazer, Cassandra; Gheorghiu, Bobby; Leaver, Chad

    2015-01-01

    This paper describes an approach which has been applied to value national outcomes of investments by federal, provincial and territorial governments, clinicians and healthcare organizations in digital health. Hypotheses are used to develop a model, which is revised and populated based upon the available evidence. Quantitative national estimates and qualitative findings are produced and validated through structured peer review processes. This methodology has applied in four studies since 2008.

  3. A Novel Method of Quantitative Anterior Chamber Depth Estimation Using Temporal Perpendicular Digital Photography.

    Science.gov (United States)

    Zamir, Ehud; Kong, George Y X; Kowalski, Tanya; Coote, Michael; Ang, Ghee Soon

    2016-07-01

    We hypothesize that: (1) Anterior chamber depth (ACD) is correlated with the relative anteroposterior position of the pupillary image, as viewed from the temporal side. (2) Such a correlation may be used as a simple quantitative tool for estimation of ACD. Two hundred sixty-six phakic eyes had lateral digital photographs taken from the temporal side, perpendicular to the visual axis, and underwent optical biometry (Nidek AL scanner). The relative anteroposterior position of the pupillary image was expressed using the ratio between: (1) lateral photographic temporal limbus to pupil distance ("E") and (2) lateral photographic temporal limbus to cornea distance ("Z"). In the first chronological half of patients (Correlation Series), E:Z ratio (EZR) was correlated with optical biometric ACD. The correlation equation was then used to predict ACD in the second half of patients (Prediction Series) and compared to their biometric ACD for agreement analysis. A strong linear correlation was found between EZR and ACD, R = -0.91, R 2 = 0.81. Bland-Altman analysis showed good agreement between predicted ACD using this method and the optical biometric ACD. The mean error was -0.013 mm (range -0.377 to 0.336 mm), standard deviation 0.166 mm. The 95% limits of agreement were ±0.33 mm. Lateral digital photography and EZR calculation is a novel method to quantitatively estimate ACD, requiring minimal equipment and training. EZ ratio may be employed in screening for angle closure glaucoma. It may also be helpful in outpatient medical clinic settings, where doctors need to judge the safety of topical or systemic pupil-dilating medications versus their risk of triggering acute angle closure glaucoma. Similarly, non ophthalmologists may use it to estimate the likelihood of acute angle closure glaucoma in emergency presentations.

  4. Scatter correction method with primary modulator for dual energy digital radiography: a preliminary study

    Science.gov (United States)

    Jo, Byung-Du; Lee, Young-Jin; Kim, Dae-Hong; Jeon, Pil-Hyun; Kim, Hee-Joung

    2014-03-01

    In conventional digital radiography (DR) using a dual energy subtraction technique, a significant fraction of the detected photons are scattered within the body, resulting in the scatter component. Scattered radiation can significantly deteriorate image quality in diagnostic X-ray imaging systems. Various methods of scatter correction, including both measurement and non-measurement-based methods have been proposed in the past. Both methods can reduce scatter artifacts in images. However, non-measurement-based methods require a homogeneous object and have insufficient scatter component correction. Therefore, we employed a measurement-based method to correct for the scatter component of inhomogeneous objects from dual energy DR (DEDR) images. We performed a simulation study using a Monte Carlo simulation with a primary modulator, which is a measurement-based method for the DEDR system. The primary modulator, which has a checkerboard pattern, was used to modulate primary radiation. Cylindrical phantoms of variable size were used to quantify imaging performance. For scatter estimation, we used Discrete Fourier Transform filtering. The primary modulation method was evaluated using a cylindrical phantom in the DEDR system. The scatter components were accurately removed using a primary modulator. When the results acquired with scatter correction and without correction were compared, the average contrast-to-noise ratio (CNR) with the correction was 1.35 times higher than that obtained without correction, and the average root mean square error (RMSE) with the correction was 38.00% better than that without correction. In the subtraction study, the average CNR with correction was 2.04 (aluminum subtraction) and 1.38 (polymethyl methacrylate (PMMA) subtraction) times higher than that obtained without the correction. The analysis demonstrated the accuracy of scatter correction and the improvement of image quality using a primary modulator and showed the feasibility of

  5. A multiparametric automatic method to monitor long-term reproducibility in digital mammography: results from a regional screening programme.

    Science.gov (United States)

    Gennaro, G; Ballaminut, A; Contento, G

    2017-09-01

    This study aims to illustrate a multiparametric automatic method for monitoring long-term reproducibility of digital mammography systems, and its application on a large scale. Twenty-five digital mammography systems employed within a regional screening programme were controlled weekly using the same type of phantom, whose images were analysed by an automatic software tool. To assess system reproducibility levels, 15 image quality indices (IQIs) were extracted and compared with the corresponding indices previously determined by a baseline procedure. The coefficients of variation (COVs) of the IQIs were used to assess the overall variability. A total of 2553 phantom images were collected from the 25 digital mammography systems from March 2013 to December 2014. Most of the systems showed excellent image quality reproducibility over the surveillance interval, with mean variability below 5%. Variability of each IQI was 5%, with the exception of one index associated with the smallest phantom objects (0.25 mm), which was below 10%. The method applied for reproducibility tests-multi-detail phantoms, cloud automatic software tool to measure multiple image quality indices and statistical process control-was proven to be effective and applicable on a large scale and to any type of digital mammography system. • Reproducibility of mammography image quality should be monitored by appropriate quality controls. • Use of automatic software tools allows image quality evaluation by multiple indices. • System reproducibility can be assessed comparing current index value with baseline data. • Overall system reproducibility of modern digital mammography systems is excellent. • The method proposed and applied is cost-effective and easily scalable.

  6. Accuracy and reliability of a novel method for fusion of digital dental casts and cone beam computed tomography scans

    NARCIS (Netherlands)

    Rangel, F.A.; Maal, T.J.J.; Bronkhorst, E.M.; Breuning, K.H.; Schols, J.G.J.H.; Berge, S.J.; Kuijpers-Jagtman, A.M.

    2013-01-01

    Several methods have been proposed to integrate digital models into Cone Beam Computed Tomography scans. Since all these methods have some drawbacks such as radiation exposure, soft tissue deformation and time-consuming digital handling processes, we propose a new method to integrate digital dental

  7. The optimal digital filters of sine and cosine transforms for geophysical transient electromagnetic method

    Science.gov (United States)

    Zhao, Yun-wei; Zhu, Zi-qiang; Lu, Guang-yin; Han, Bo

    2018-03-01

    The sine and cosine transforms implemented with digital filters have been used in the Transient electromagnetic methods for a few decades. Kong (2007) proposed a method of obtaining filter coefficients, which are computed in the sample domain by Hankel transform pair. However, the curve shape of Hankel transform pair changes with a parameter, which usually is set to be 1 or 3 in the process of obtaining the digital filter coefficients of sine and cosine transforms. First, this study investigates the influence of the parameter on the digital filter algorithm of sine and cosine transforms based on the digital filter algorithm of Hankel transform and the relationship between the sine, cosine function and the ±1/2 order Bessel function of the first kind. The results show that the selection of the parameter highly influences the precision of digital filter algorithm. Second, upon the optimal selection of the parameter, it is found that an optimal sampling interval s also exists to achieve the best precision of digital filter algorithm. Finally, this study proposes four groups of sine and cosine transform digital filter coefficients with different length, which may help to develop the digital filter algorithm of sine and cosine transforms, and promote its application.

  8. Partial digitization method of wave processes in rail lines on the discrete basis

    International Nuclear Information System (INIS)

    Tyurekhodzhaev, A.N.; Ibraev, A.G.

    2006-01-01

    Analytical solution of the problem about longitudinal vibration of the rail which lies on the ties taking into account contact dry friction between wheel and rail is provided by the method of partial digitization and Laplace dual integral transformation. (author)

  9. 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)

  10. Methodological Appendix of Research Methods Employed in the Mexican American Education Study.

    Science.gov (United States)

    Commission on Civil Rights, Washington, DC.

    The U.S. Commission on Civil Rights released Mexican American Education Study findings in a series of documents: (1) "The Ethnic Isolation of Mexican Americans in the Public Schools of the Southwest" (ED 052 849), "The Unfinished Education" (ED 056 821), and "The Excluded Student" (ED 062 069). The research methods employed in the study are…

  11. Digital Badges for STEM Learning in Secondary Contexts: A Mixed Methods Study

    Science.gov (United States)

    Elkordy, Angela

    The deficit in STEM skills is a matter of concern for national economies and a major focus for educational policy makers. The development of Information and Communications Technologies (ICT) has resulted in a rapidly changing workforce of global scale. In addition, ICT have fostered the growth of digital and mobile technologies which have been the learning context, formal and informal, for a generation of youth. The purpose of this study was to design an intervention based upon a competency-based, digitally-mediated, learning intervention: digital badges for learning STEM habits of mind and practices. Designed purposefully, digital badge learning trajectories and criteria can be flexible tools for scaffolding, measuring, and communicating the acquisition of knowledge, skills, or competencies. One of the most often discussed attributes of digital badges, is the ability of badges to motivate learners. However, the research base to support this claim is in its infancy; there is little empirical evidence. A skills-based digital badge intervention was designed to demonstrate mastery learning in key, age-appropriate, STEM competencies aligned with Next Generation Science Standards (NGSS) and other educational standards. A mixed methods approach was used to study the impact of a digital badge intervention in the sample middle and high school population. Among the findings were statistically significant measures which substantiate that in this student population, the digital badges increased perceived competence and motivated learners to persist at task.

  12. Conventional and digital radiographic methods in the detection of simulated external root resorptions: A comparative study

    Directory of Open Access Journals (Sweden)

    C J Sanjay

    2009-01-01

    Full Text Available Objective : To evaluate and compare the efficacy of conventional and digital radiographic methods in the detection of simulated external root resorption cavities and also to evaluate whether the detectability was influenced by resorption cavity sizes. Methods : Thirty-two selected teeth from human dentate mandibles were radiographed in orthoradial, mesioradial and distoradial aspect using conventional film (Insight Kodak F-speed; Eastman Kodak, Rochester, NY and a digital sensor (Trophy RVG advanced imaging system with 0.7mm and 1.0mm deep cavities prepared on their vestibular, mesial and distal surfaces at the cervical, middle and apical thirds. Three dental professionals, an endodontist, a radiologist and a general practitioner, evaluated the images twice with a one-week time interval. Results : No statistical significance was seen in the first observation for both conventional and digital radiographic methods in the detection of simulated external root resorptions and for small and medium cavities but statistical difference was noted in the second observation (P< 0.001 for both the methods. Conclusion : Considering the methodology and the overall results, conventional radiographic method (F-speed performed slightly better than the digital radiographic method in the detection of simulated radiographic method but better consistency was seen with the digital system. Overall size of the resorption cavity had no influence on the performance of both methods and suggests that initial external root resorption lesion is not well-appreciated with both the methods as compared to the advanced lesion.

  13. Quantitative evaluation of fault coverage for digitalized systems in NPPs using simulated fault injection method

    International Nuclear Information System (INIS)

    Kim, Suk Joon

    2004-02-01

    Even though digital systems have numerous advantages such as precise processing of data, enhanced calculation capability over the conventional analog systems, there is a strong restriction on the application of digital systems to the safety systems in nuclear power plants (NPPs). This is because we do not fully understand the reliability of digital systems, and therefore we cannot guarantee the safety of digital systems. But, as the need for introduction of digital systems to safety systems in NPPs increasing, the need for the quantitative analysis on the safety of digital systems is also increasing. NPPs, which are quite conservative in terms of safety, require proving the reliability of digital systems when applied them to the NPPs. Moreover, digital systems which are applied to the NPPs are required to increase the overall safety of NPPs. however, it is very difficult to evaluate the reliability of digital systems because they include the complex fault processing mechanisms at various levels of the systems. Software is another obstacle in reliability assessment of the systems that requires ultra-high reliability. In this work, the fault detection coverage for the digital system is evaluated using simulated fault injection method. The target system is the Local Coincidence Logic (LCL) processor in Digital Plant Protection System (DPPS). However, as the LCL processor is difficult to design equally for evaluating the fault detection coverage, the LCL system has to be simplified. The simulations for evaluating the fault detection coverage of components are performed by dividing into two cases and the failure rates of components are evaluated using MIL-HDBK-217F. Using these results, the fault detection coverage of simplified LCL system is evaluated. In the experiments, heartbeat signals were just emitted at regular interval after executing logic without self-checking algorithm. When faults are injected into the simplified system, fault occurrence can be detected by

  14. Trends in study design and the statistical methods employed in a leading general medicine journal.

    Science.gov (United States)

    Gosho, M; Sato, Y; Nagashima, K; Takahashi, S

    2018-02-01

    Study design and statistical methods have become core components of medical research, and the methodology has become more multifaceted and complicated over time. The study of the comprehensive details and current trends of study design and statistical methods is required to support the future implementation of well-planned clinical studies providing information about evidence-based medicine. Our purpose was to illustrate study design and statistical methods employed in recent medical literature. This was an extension study of Sato et al. (N Engl J Med 2017; 376: 1086-1087), which reviewed 238 articles published in 2015 in the New England Journal of Medicine (NEJM) and briefly summarized the statistical methods employed in NEJM. Using the same database, we performed a new investigation of the detailed trends in study design and individual statistical methods that were not reported in the Sato study. Due to the CONSORT statement, prespecification and justification of sample size are obligatory in planning intervention studies. Although standard survival methods (eg Kaplan-Meier estimator and Cox regression model) were most frequently applied, the Gray test and Fine-Gray proportional hazard model for considering competing risks were sometimes used for a more valid statistical inference. With respect to handling missing data, model-based methods, which are valid for missing-at-random data, were more frequently used than single imputation methods. These methods are not recommended as a primary analysis, but they have been applied in many clinical trials. Group sequential design with interim analyses was one of the standard designs, and novel design, such as adaptive dose selection and sample size re-estimation, was sometimes employed in NEJM. Model-based approaches for handling missing data should replace single imputation methods for primary analysis in the light of the information found in some publications. Use of adaptive design with interim analyses is increasing

  15. Reconstruction of on-axis lensless Fourier transform digital hologram with the screen division method

    Science.gov (United States)

    Jiang, Hongzhen; Liu, Xu; Liu, Yong; Li, Dong; Chen, Zhu; Zheng, Fanglan; Yu, Deqiang

    2017-10-01

    An effective approach for reconstructing on-axis lensless Fourier Transform digital hologram by using the screen division method is proposed. Firstly, the on-axis Fourier Transform digital hologram is divided into sub-holograms. Then the reconstruction result of every sub-hologram is obtained according to the position of corresponding sub-hologram in the hologram reconstruction plane with Fourier transform operation. Finally, the reconstruction image of on-axis Fourier Transform digital hologram can be acquired by the superposition of the reconstruction result of sub-holograms. Compared with the traditional reconstruction method with the phase shifting technology, in which multiple digital holograms are required to record for obtaining the reconstruction image, this method can obtain the reconstruction image with only one digital hologram and therefore greatly simplify the recording and reconstruction process of on-axis lensless Fourier Transform digital holography. The effectiveness of the proposed method is well proved with the experimental results and it will have potential application foreground in the holographic measurement and display field.

  16. Digital storytelling as a method in health research: a systematic review protocol.

    Science.gov (United States)

    Rieger, Kendra L; West, Christina H; Kenny, Amanda; Chooniedass, Rishma; Demczuk, Lisa; Mitchell, Kim M; Chateau, Joanne; Scott, Shannon D

    2018-03-05

    Digital storytelling is an arts-based research method with potential to elucidate complex narratives in a compelling manner, increase participant engagement, and enhance the meaning of research findings. This method involves the creation of a 3- to 5-min video that integrates multimedia materials including photos, participant voices, drawings, and music. Given the significant potential of digital storytelling to meaningfully capture and share participants' lived experiences, a systematic review of its use in healthcare research is crucial to develop an in-depth understanding of how researchers have used this method, with an aim to refine and further inform future iterations of its use. We aim to identify and synthesize evidence on the use, impact, and ethical considerations of using digital storytelling in health research. The review questions are as follows: (1) What is known about the purpose, definition, use (processes), and contexts of digital storytelling as part of the research process in health research? (2) What impact does digital storytelling have upon the research process, knowledge development, and healthcare practice? (3) What are the key ethical considerations when using digital storytelling within qualitative, quantitative, and mixed method research studies? Key databases and the grey literature will be searched from 1990 to the present for qualitative, quantitative, and mixed methods studies that utilized digital storytelling as part of the research process. Two independent reviewers will screen and critically appraise relevant articles with established quality appraisal tools. We will extract narrative data from all studies with a standardized data extraction form and conduct a thematic analysis of the data. To facilitate innovative dissemination through social media, we will develop a visual infographic and three digital stories to illustrate the review findings, as well as methodological and ethical implications. In collaboration with national

  17. Decorative design of ceramic tiles adapted to inkjet printing employing digital image processing; Diseno decorativo de pavimentos ceramicos adaptado a inyeccion de tinta mediante tratamiento digital de imagen

    Energy Technology Data Exchange (ETDEWEB)

    Defez, B.; Santiago-Praderas, V.; Lluna, E.; Peris-Fajarnes, G.; Dunai, E.

    2013-09-01

    The ceramic tile sector is a very competitive industry. The designer's proficiency to offer new models of the decorated surface, adapted to the production means, plays a very important role in the competitiveness. In the present work, we analyze the evolution of the design process in the ceramic sector, as much as the changes experimented in parallel by the printing equipment. Afterwards, we present a new concept of ceramic design, based on digital image processing. This technique allows the generation of homogeneous and non-repetitive designs for large surfaces, especially thought for inkjet printing. With the programmed algorithms we have compiled a prototype software for the assistance of the ceramic design. This tool allows creating continuous designs for large surfaces saving developing time. (Author)

  18. Systems and methods for automatically identifying and linking names in digital resources

    Science.gov (United States)

    Parker, Charles T.; Lyons, Catherine M.; Roston, Gerald P.; Garrity, George M.

    2017-06-06

    The present invention provides systems and methods for automatically identifying name-like-strings in digital resources, matching these name-like-string against a set of names held in an expertly curated database, and for those name-like-strings found in said database, enhancing the content by associating additional matter with the name, wherein said matter includes information about the names that is held within said database and pointers to other digital resources which include the same name and it synonyms.

  19. In vivo precision of conventional and digital methods for obtaining quadrant dental impressions

    OpenAIRE

    Ender, Andreas; Zimmermann, Moritz; Attin, Thomas; Mehl, Albert

    2016-01-01

    OBJECTIVES Quadrant impressions are commonly used as alternative to full-arch impressions. Digital impression systems provide the ability to take these impressions very quickly; however, few studies have investigated the accuracy of the technique in vivo. The aim of this study is to assess the precision of digital quadrant impressions in vivo in comparison to conventional impression techniques. MATERIALS AND METHODS Impressions were obtained via two conventional (metal full-arch tray, CI, ...

  20. A three-frame digital image correlation (DIC) method for the measurement of small displacements and strains

    International Nuclear Information System (INIS)

    Cofaru, C; Philips, W; Van Paepegem, W

    2012-01-01

    Digital image correlation (DIC) has become a well-established approach for the calculation of full-field displacement and strains within the field of experimental mechanics. Since their introduction, DIC methods have been relying on only two images to measure the displacements and strains that materials undergo under load. It can be foreseen that the use of additional image information for the calculus of displacements and strains, although computationally more expensive, can positively impact DIC method accuracy under both ideal and challenging experimental conditions. Such accuracy improvements are especially important when measuring very small deformations, which still constitutes a great challenge: small displacements and strains translate into equally small digital image intensity changes on the material’s surface, which are affected by the digitization processes of the imaging hardware and by other image acquisition effects such as image noise. This paper proposes a new three-frame Newton–Raphson DIC method and evaluates it from the standpoints of accuracy and speed. The method models the deformations that are to be measured under the assumption that the deformation occurs at approximately the same rate between each two consecutive images in the three image sequences that are employed. The aim is to investigate how the use of image data from more than two images impacts accuracy and what is the effect on the computational speed. The proposed method is compared with the classic two-frame Newton–Raphson method in three experiments. Two experiments rely on numerically deformed images that simulate heterogeneous deformations. The third experiment uses images from a real deformation experiment. Results indicate that although it is computationally more demanding, the three-frame method significantly improves displacement and strain accuracy and is less sensitive to image noise. (paper)

  1. Construction of a digital elevation model: methods and parallelization

    International Nuclear Information System (INIS)

    Mazzoni, Christophe

    1995-01-01

    The aim of this work is to reduce the computation time needed to produce the Digital Elevation Models (DEM) by using a parallel machine. It is made in collaboration between the French 'Institut Geographique National' (IGN) and the Laboratoire d'Electronique de Technologie et d'Instrumentation (LETI) of the French Atomic Energy Commission (CEA). The IGN has developed a system which provides DEM that is used to produce topographic maps. The kernel of this system is the correlator, a software which automatically matches pairs of homologous points of a stereo-pair of photographs. Nevertheless the correlator is expensive In computing time. In order to reduce computation time and to produce the DEM with same accuracy that the actual system, we have parallelized the IGN's correlator on the OPENVISION system. This hardware solution uses a SIMD (Single Instruction Multiple Data) parallel machine SYMPATI-2, developed by the LETI that is involved in parallel architecture and image processing. Our analysis of the implementation has demonstrated the difficulty of efficient coupling between scalar and parallel structure. So we propose solutions to reinforce this coupling. In order to accelerate more the processing we evaluate SYMPHONIE, a SIMD calculator, successor of SYMPATI-2. On an other hand, we developed a multi-agent approach for what a MIMD (Multiple Instruction, Multiple Data) architecture is available. At last, we describe a Multi-SIMD architecture that conciliates our two approaches. This architecture offers a capacity to apprehend efficiently multi-level treatment image. It is flexible by its modularity, and its communication network supplies reliability that interest sensible systems. (author) [fr

  2. Tooth-size discrepancy: A comparison between manual and digital methods

    Directory of Open Access Journals (Sweden)

    Gabriele Dória Cabral Correia

    2014-08-01

    Full Text Available INTRODUCTION: Technological advances in Dentistry have emerged primarily in the area of diagnostic tools. One example is the 3D scanner, which can transform plaster models into three-dimensional digital models. OBJECTIVE: This study aimed to assess the reliability of tooth size-arch length discrepancy analysis measurements performed on three-dimensional digital models, and compare these measurements with those obtained from plaster models. MATERIAL AND METHODS: To this end, plaster models of lower dental arches and their corresponding three-dimensional digital models acquired with a 3Shape R700T scanner were used. All of them had lower permanent dentition. Four different tooth size-arch length discrepancy calculations were performed on each model, two of which by manual methods using calipers and brass wire, and two by digital methods using linear measurements and parabolas. RESULTS: Data were statistically assessed using Friedman test and no statistically significant differences were found between the two methods (P > 0.05, except for values found by the linear digital method which revealed a slight, non-significant statistical difference. CONCLUSIONS: Based on the results, it is reasonable to assert that any of these resources used by orthodontists to clinically assess tooth size-arch length discrepancy can be considered reliable.

  3. World directory of crystallographers and of other scientists employing crystallographic methods

    CERN Document Server

    Filippini, G; Hashizume, H; Torriani, I; Duax, W

    1995-01-01

    The 9th edition of the World Directory of Crystallographers and of Other Scientists Employing Crystallographic Methods, which contains 7907 entries embracing 72 countries, differs considerably from the 8th edition, published in 1990. The content has been updated, and the methods used to acquire the information presented and to produce this new edition of the Directory have involved the latest advances in technology. The Directory is now also available as a regularly updated electronic database, accessible via e-mail, Telnet, Gopher, World-Wide Web, and Mosaic. Full details are given in an Appendix to the printed edition.

  4. Digital baseline estimation method for multi-channel pulse height analyzing

    International Nuclear Information System (INIS)

    Xiao Wuyun; Wei Yixiang; Ai Xianyun

    2005-01-01

    The basic features of digital baseline estimation for multi-channel pulse height analysis are introduced. The weight-function of minimum-noise baseline filter is deduced with functional variational calculus. The frequency response of this filter is also deduced with Fourier transformation, and the influence of parameters on amplitude frequency response characteristics is discussed. With MATLAB software, the noise voltage signal from the charge sensitive preamplifier is simulated, and the processing effect of minimum-noise digital baseline estimation is verified. According to the results of this research, digital baseline estimation method can estimate baseline optimally, and it is very suitable to be used in digital multi-channel pulse height analysis. (authors)

  5. A High-Dynamic-Range Optical Remote Sensing Imaging Method for Digital TDI CMOS

    Directory of Open Access Journals (Sweden)

    Taiji Lan

    2017-10-01

    Full Text Available The digital time delay integration (digital TDI technology of the complementary metal-oxide-semiconductor (CMOS image sensor has been widely adopted and developed in the optical remote sensing field. However, the details of targets that have low illumination or low contrast in scenarios of high contrast are often drowned out because of the superposition of multi-stage images in digital domain multiplies the read noise and the dark noise, thus limiting the imaging dynamic range. Through an in-depth analysis of the information transfer model of digital TDI, this paper attempts to explore effective ways to overcome this issue. Based on the evaluation and analysis of multi-stage images, the entropy-maximized adaptive histogram equalization (EMAHE algorithm is proposed to improve the ability of images to express the details of dark or low-contrast targets. Furthermore, in this paper, an image fusion method is utilized based on gradient pyramid decomposition and entropy weighting of different TDI stage images, which can improve the detection ability of the digital TDI CMOS for complex scenes with high contrast, and obtain images that are suitable for recognition by the human eye. The experimental results show that the proposed methods can effectively improve the high-dynamic-range imaging (HDRI capability of the digital TDI CMOS. The obtained images have greater entropy and average gradients.

  6. Mathematical methods in time series analysis and digital image processing

    CERN Document Server

    Kurths, J; Maass, P; Timmer, J

    2008-01-01

    The aim of this volume is to bring together research directions in theoretical signal and imaging processing developed rather independently in electrical engineering, theoretical physics, mathematics and the computer sciences. In particular, mathematically justified algorithms and methods, the mathematical analysis of these algorithms, and methods as well as the investigation of connections between methods from time series analysis and image processing are reviewed. An interdisciplinary comparison of these methods, drawing upon common sets of test problems from medicine and geophysical/enviromental sciences, is also addressed. This volume coherently summarizes work carried out in the field of theoretical signal and image processing. It focuses on non-linear and non-parametric models for time series as well as on adaptive methods in image processing.

  7. Evaluation of the image quality in digital breast tomosynthesis (DBT) employed with a compressed-sensing (CS)-based reconstruction algorithm by using the mammographic accreditation phantom

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yeonok; Cho, Heemoon; Je, Uikyu; Cho, Hyosung, E-mail: hscho1@yonsei.ac.kr; Park, Chulkyu; Lim, Hyunwoo; Kim, Kyuseok; Kim, Guna; Park, Soyoung; Woo, Taeho; Choi, Sungil

    2015-12-21

    In this work, we have developed a prototype digital breast tomosynthesis (DBT) system which mainly consists of an x-ray generator (28 kV{sub p}, 7 mA s), a CMOS-type flat-panel detector (70-μm pixel size, 230.5×339 mm{sup 2} active area), and a rotational arm to move the x-ray generator in an arc. We employed a compressed-sensing (CS)-based reconstruction algorithm, rather than a common filtered-backprojection (FBP) one, for more accurate DBT reconstruction. Here the CS is a state-of-the-art mathematical theory for solving the inverse problems, which exploits the sparsity of the image with substantially high accuracy. We evaluated the reconstruction quality in terms of the detectability, the contrast-to-noise ratio (CNR), and the slice-sensitive profile (SSP) by using the mammographic accreditation phantom (Model 015, CIRS Inc.) and compared it to the FBP-based quality. The CS-based algorithm yielded much better image quality, preserving superior image homogeneity, edge sharpening, and cross-plane resolution, compared to the FBP-based one. - Highlights: • A prototype digital breast tomosynthesis (DBT) system is developed. • Compressed-sensing (CS) based reconstruction framework is employed. • We reconstructed high-quality DBT images by using the proposed reconstruction framework.

  8. Anthropology with algorithms? An exploration of online drug knowledge using digital methods

    NARCIS (Netherlands)

    Krieg, L.J.; Berning, M.; Hardon, A.

    2017-01-01

    Based on a study of more than twenty thousand reports on drug experiences from the online drug education portal Erowid, this article argues that the integration of ethnographic methods with computational methods and digital data analysis, including so-called big data, is not only possible but highly

  9. The Temporal Fabric of Research Methods: Posthuman Social Science and the Digital Data Deluge

    Science.gov (United States)

    de Freitas, Elizabeth

    2017-01-01

    The aim of this paper is to adumbrate methods more suitable to a posthuman social science, so as to better attend to the digital datafication of life. Five core functions of research method are presented. The first three--the desire for origins, the need to exclude, and the establishment of a regime of labour--often reinstate social orders and…

  10. A comparative study on the HW reliability assessment methods for digital I and C equipment

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hoan Sung; Sung, T. Y.; Eom, H. S.; Park, J. K.; Kang, H. G.; Lee, G. Y. [Korea Atomic Energy Research Institute, Taejeon (Korea); Kim, M. C. [Korea Advanced Institute of Science and Technology, Taejeon (Korea); Jun, S. T. [KHNP, Taejeon (Korea)

    2002-03-01

    It is necessary to predict or to evaluate the reliability of electronic equipment for the probabilistic safety analysis of digital instrument and control equipment. But most databases for the reliability prediction have no data for the up-to-date equipment and the failure modes are not classified. The prediction results for the specific component show different values according to the methods and databases. For boards and systems each method shows different values than others also. This study is for reliability prediction of PDC system for Wolsong NPP1 as a digital I and C equipment. Various reliability prediction methods and failure databases are used in calculation of the reliability to compare the effects of sensitivity and accuracy of each model and database. Many considerations for the reliability assessment of digital systems are derived with the results of this study. 14 refs., 19 figs., 15 tabs. (Author)

  11. A new digital preoperative planning method for total hip arthroplasties

    NARCIS (Netherlands)

    Crooijmans, H.J.A.; Laumen, A.M.R.P.; van Pul, C.; van Mourik, J.B.A.

    Preoperative templating is an important part of a THA. The ability to accurately determine magnification of the hip on the radiograph and apply identical magnification to the radiograph and template will improve accuracy of preoperative templating of THA. We designed a templating method using a new

  12. Method and device for decoding coded digital video signals

    NARCIS (Netherlands)

    2000-01-01

    The invention relates to a video coding method and system including a quantization and coding sub-assembly (38) in which a quantization parameter is controlled by another parameter defined as being in direct relation with the dynamic range value of the data contained in given blocks of pixels.

  13. Method for improved reading of a digital data disc

    DEFF Research Database (Denmark)

    2004-01-01

    Method for regulating the control signal for adjustment of the optical path between a data disc and a signal pick-up detector system in a data disc drive, where the control is regulated as a response to the deviation of the actual reading signals from expected reading signals, and wherein...

  14. Efficiency Optimization Methods in Low-Power High-Frequency Digitally Controlled SMPS

    Directory of Open Access Journals (Sweden)

    Aleksandar Prodić

    2010-06-01

    Full Text Available This paper gives a review of several power efficiency optimization techniques that are utilizing advantages of emerging digital control in high frequency switch-mode power supplies (SMPS, processing power from a fraction of watt to several hundreds of watts. Loss mechanisms in semiconductor components are briefly reviewed and the related principles of online efficiency optimization through power stage segmentation and gate voltage variation presented. Practical implementations of such methods utilizing load prediction or data extraction from a digital control loop are shown. The benefits of the presented efficiency methods are verified through experimental results, showing efficiency improvements, ranging from 2% to 30%,depending on the load conditions.

  15. [Comparison of digital and visual methods for Ki-67 assessment in invasive breast carcinomas].

    Science.gov (United States)

    Kushnarev, V A; Artemyeva, E S; Kudaybergenova, A G

    2018-01-01

    to compare two methods for quantitative assessment of the proliferative activity index (PAI): a visual estimation method by several investigators and digital image analysis (DIA). The use of the Ki-67 index in the daily clinical practice of a Morbid Anatomy Department is associated with the problem of reproducibility of quantitative assessment of the Ki-67 PAI. Due to the development of digital imaging techniques in morphology, new methods for PAI evaluation using the DIA are proposed. The Ki-67 PAI data obtained during visual assessment and digital image analysis were compared in 104 cases of grades 2-3 breast carcinoma. The histological sections were scanned using a Panoramic III scanner (3D Histech, Hungary) and digital images were obtained. DIA was carried out using the software 3D Histech QuantCenter (3D Histech, Hungary), by marking 3-10 zones. Evaluation of the obtained sections was done independently by two investigators engaged in cancer pathology. The level of agreement between visual and digital methods did not differ significantly (p>0.001). The authors selected a gray area in the range of 10-35% IPA, where the Ki-67 index showed a weak relationship between the analyzed groups (ICC, 0.47). The Ki67 index below 10% and above 35% showed a sufficient reproducibility in the same laboratory. The authors consider that the scanned digital form of a histological section, which can be evaluated using automated software analysis modules, is an independent and objective method to assess proliferative activity for Ki-67 index validation.

  16. Estimation of optimum time interval for neutron- γ discrimination by simplified digital charge collection method

    International Nuclear Information System (INIS)

    Singh, Harleen; Singh, Sarabjeet

    2014-01-01

    The discrimination of mixed radiation field is of prime importance due to its application in neutron detection which leads to radiation safety, nuclear material detection etc. The liquid scintillators are one of the most important radiation detectors because the relative decay rate of neutron pulse is slower as compared to gamma radiation in these detectors. There are techniques like zero crossing and charge comparison which are very popular and implemented using analogue electronics. In the recent years due to availability of fast ADC and FPGA, digital methods for discrimination of mixed field radiations have been investigated. Some of the digital time domain techniques developed are pulse gradient analysis (PGA), simplified digital charge collection method (SDCC), digital zero crossing method. The performance of these methods depends on the appropriate selection of gate time for which the pulse is processed. In this paper, the SDCC method is investigated for a neutron-gamma mixed field. The main focus of the study is to get the knowledge of optimum gate time which is very important in neutron gamma discrimination analysis in a mixed radiation field. The comparison with charge collection (CC) method is also investigated

  17. Empirical method for simulation of water tables by digital computers

    International Nuclear Information System (INIS)

    Carnahan, C.L.; Fenske, P.R.

    1975-09-01

    An empirical method is described for computing a matrix of water-table elevations from a matrix of topographic elevations and a set of observed water-elevation control points which may be distributed randomly over the area of interest. The method is applicable to regions, such as the Great Basin, where the water table can be assumed to conform to a subdued image of overlying topography. A first approximation to the water table is computed by smoothing a matrix of topographic elevations and adjusting each node of the smoothed matrix according to a linear regression between observed water elevations and smoothed topographic elevations. Each observed control point is assumed to exert a radially decreasing influence on the first approximation surface. The first approximation is then adjusted further to conform to observed water-table elevations near control points. Outside the domain of control, the first approximation is assumed to represent the most probable configuration of the water table. The method has been applied to the Nevada Test Site and the Hot Creek Valley areas in Nevada

  18. Comparison of Three Supervised Learning Methods for Digital Soil Mapping: Application to a Complex Terrain in the Ecuadorian Andes

    Directory of Open Access Journals (Sweden)

    Martin Hitziger

    2014-01-01

    Full Text Available A digital soil mapping approach is applied to a complex, mountainous terrain in the Ecuadorian Andes. Relief features are derived from a digital elevation model and used as predictors for topsoil texture classes sand, silt, and clay. The performance of three statistical learning methods is compared: linear regression, random forest, and stochastic gradient boosting of regression trees. In linear regression, a stepwise backward variable selection procedure is applied and overfitting is controlled by minimizing Mallow’s Cp. For random forest and boosting, the effect of predictor selection and tuning procedures is assessed. 100-fold repetitions of a 5-fold cross-validation of the selected modelling procedures are employed for validation, uncertainty assessment, and method comparison. Absolute assessment of model performance is achieved by comparing the prediction error of the selected method and the mean. Boosting performs best, providing predictions that are reliably better than the mean. The median reduction of the root mean square error is around 5%. Elevation is the most important predictor. All models clearly distinguish ridges and slopes. The predicted texture patterns are interpreted as result of catena sequences (eluviation of fine particles on slope shoulders and landslides (mixing up mineral soil horizons on slopes.

  19. Digital Ethnography of Zoophilia - A Multinational Mixed-Methods Study.

    Science.gov (United States)

    Sendler, Damian Jacob; Lew-Starowicz, Michal

    2018-05-10

    This study investigates people who have sex with animals (PSA) by describing their living situation, sexual activity, beliefs, and attitudes toward stigmatization. These data are highly applicable to the work of psychiatric and forensic professionals investigating paraphilias. We apply mixed-methods approach, using qualitative and quantitative analyses. The findings come from anonymous forum postings of 953 participants; of which 345 agreed to complete a survey upon advertising the study. We identify several themes, describing concerns of zoosexuals chatting within online communities: living situation; sex life; social acceptability; getting help. First, we provide data on how PSA justify their relationships with animal sex partners - with particular emphasis on sex practices and physical features most attractive to them. Second, we elaborate on the stigma associated with being a zoosexual, including the coping mechanism for dealing with social ostracism. Third, we elaborate, in detail, on why PSA find animals sexually appealing. Lastly, we present evidence that online discussion spaces serve as the platform for help-seeking behavior for individuals with paraphilias. This study presents the largest analyses of zoophiles in modern history, using mixed-methods approach, uncovering their daily activities, sexual preferences, and help-seeking behavior.

  20. Ultrasonic Digital Communication System for a Steel Wall Multipath Channel: Methods and Results

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Timothy L. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2005-12-01

    As of the development of this thesis, no commercially available products have been identified for the digital communication of instrumented data across a thick ({approx} 6 n.) steel wall using ultrasound. The specific goal of the current research is to investigate the application of methods for digital communication of instrumented data (i.e., temperature, voltage, etc.) across the wall of a steel pressure vessel. The acoustic transmission of data using ultrasonic transducers prevents the need to breach the wall of such a pressure vessel which could ultimately affect its safety or lifespan, or void the homogeneity of an experiment under test. Actual digital communication paradigms are introduced and implemented for the successful dissemination of data across such a wall utilizing solely an acoustic ultrasonic link. The first, dubbed the ''single-hop'' configuration, can communicate bursts of digital data one-way across the wall using the Differential Binary Phase-Shift Keying (DBPSK) modulation technique as fast as 500 bps. The second, dubbed the ''double-hop'' configuration, transmits a carrier into the vessel, modulates it, and retransmits it externally. Using a pulsed carrier with Pulse Amplitude Modulation (PAM), this technique can communicate digital data as fast as 500 bps. Using a CW carrier, Least Mean-Squared (LMS) adaptive interference suppression, and DBPSK, this method can communicate data as fast as 5 kbps. A third technique, dubbed the ''reflected-power'' configuration, communicates digital data by modulating a pulsed carrier by varying the acoustic impedance at the internal transducer-wall interface. The paradigms of the latter two configurations are believed to be unique. All modulation methods are based on the premise that the wall cannot be breached in any way and can therefore be viably implemented with power delivered wirelessly through the acoustic channel using ultrasound. Methods

  1. In vivo precision of conventional and digital methods of obtaining complete-arch dental impressions.

    Science.gov (United States)

    Ender, Andreas; Attin, Thomas; Mehl, Albert

    2016-03-01

    Digital impression systems have undergone significant development in recent years, but few studies have investigated the accuracy of the technique in vivo, particularly compared with conventional impression techniques. The purpose of this in vivo study was to investigate the precision of conventional and digital methods for complete-arch impressions. Complete-arch impressions were obtained using 5 conventional (polyether, POE; vinylsiloxanether, VSE; direct scannable vinylsiloxanether, VSES; digitized scannable vinylsiloxanether, VSES-D; and irreversible hydrocolloid, ALG) and 7 digital (CEREC Bluecam, CER; CEREC Omnicam, OC; Cadent iTero, ITE; Lava COS, LAV; Lava True Definition Scanner, T-Def; 3Shape Trios, TRI; and 3Shape Trios Color, TRC) techniques. Impressions were made 3 times each in 5 participants (N=15). The impressions were then compared within and between the test groups. The cast surfaces were measured point-to-point using the signed nearest neighbor method. Precision was calculated from the (90%-10%)/2 percentile value. The precision ranged from 12.3 μm (VSE) to 167.2 μm (ALG), with the highest precision in the VSE and VSES groups. The deviation pattern varied distinctly according to the impression method. Conventional impressions showed the highest accuracy across the complete dental arch in all groups, except for the ALG group. Conventional and digital impression methods differ significantly in the complete-arch accuracy. Digital impression systems had higher local deviations within the complete arch cast; however, they achieve equal and higher precision than some conventional impression materials. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  2. Digital control system of a steam generator water level by LQG optimal method

    International Nuclear Information System (INIS)

    Lee, Yoon Joon

    1993-01-01

    A digital control system for the steam generator water level control is developed using LQG optimal design method. To describe the more realistic situaton, a feedwater valve actuator is assumed to be of the first order lagger and is included in the overall control system. By composing the digital control circuit in such a way that the overall control system consists of two sub-systems of feedwater station and feedback loop digital controller, the design procedure is divided into two independent steps. The feedwater station system is described in the error dynamics of an ordinary regulator system. The optimal gains are obtained by LQ method which imposes the constraints of the feedwater valve motion as well as on the output deviations. Developed also is a Kalman observer on account of the flow measurement uncertainty at low power. Then a digital controller on the feedback loop is designed so that the system maintains the same stability margins for all power ranges. The simulation results show thst the optimal digital system has a good control characteristics despite the adverse dynamics of a steam generator at low power. (Author)

  3. Digital Materials Related to Food Science and Cooking Methods for Preparing Eggs

    OpenAIRE

    沼田, 貴美子; 渡邉, 美奈; ヌマタ, キミコ; ワタナベ, ミナ; Numata, Kimiko; Watanabe, Mina

    2009-01-01

    We studied methods that were effective for teaching cooking to elementary school pupils using home economics materials. The subject was "Iritamago (scrambled eggs)". We researched the relationship between cookery science and experimental methods of making Iritamago. The various differences in condition and texture of Iritamago were compared among the different cooking utensils, conditions, and preparations of eggs. We created digital materials related to cookery science and the cooking method...

  4. A Digital Mixed Methods Research Design: Integrating Multimodal Analysis with Data Mining and Information Visualization for Big Data Analytics

    Science.gov (United States)

    O'Halloran, Kay L.; Tan, Sabine; Pham, Duc-Son; Bateman, John; Vande Moere, Andrew

    2018-01-01

    This article demonstrates how a digital environment offers new opportunities for transforming qualitative data into quantitative data in order to use data mining and information visualization for mixed methods research. The digital approach to mixed methods research is illustrated by a framework which combines qualitative methods of multimodal…

  5. The Effectiveness of Teaching Methods Used in Graphic Design Pedagogy in Both Analogue and Digital Education Systems

    Science.gov (United States)

    Alhajri, Salman

    2016-01-01

    Purpose: this paper investigates the effectiveness of teaching methods used in graphic design pedagogy in both analogue and digital education systems. Methodology and approach: the paper is based on theoretical study using a qualitative, case study approach. Comparison between the digital teaching methods and traditional teaching methods was…

  6. Methods for the analysis of azo dyes employed in food industry--A review.

    Science.gov (United States)

    Yamjala, Karthik; Nainar, Meyyanathan Subramania; Ramisetti, Nageswara Rao

    2016-02-01

    A wide variety of azo dyes are generally added for coloring food products not only to make them visually aesthetic but also to reinstate the original appearance lost during the production process. However, many countries in the world have banned the use of most of the azo dyes in food and their usage is highly regulated by domestic and export food supplies. The regulatory authorities and food analysts adopt highly sensitive and selective analytical methods for monitoring as well as assuring the quality and safety of food products. The present manuscript presents a comprehensive review of various analytical techniques used in the analysis of azo dyes employed in food industries of different parts of the world. A brief description on the use of different extraction methods such as liquid-liquid, solid phase and membrane extraction has also been presented. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. A simple method employed for the treatment of filters used in atmospheric pollution studies

    International Nuclear Information System (INIS)

    Prendez B, M.M.; Ortiz C, J.L.; Garrido, J.I.; Huerta P, R.; Alvarez B, C.; Zolezzi C, S.R.

    1983-01-01

    A simple and rapid method for the multielement routine analysis of atmospheric particulate matter is described. The samples collected on four different types of filters were treated with HNO 3 and HCl at 110-120 deg C in pyrex glassware. Time required for the different stages of the treatment was determined by using 60 Co, 65 Zn and 137 Cs as radioactive tracers. Atomic absorption spectrophotometry was used to determine the concentration of the elements. The efficiency for 11 elements (Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Hg and Pb) was determined. The method was succesfully employed for the treatment of filters used in atmospheric pollution studies in both urban and rural areas. (author)

  8. General method of synthesis by PLIC/FPGA digital devices to ...

    African Journals Online (AJOL)

    A general method is proposed to synthesize digital devices in order to perform discrete orthogonal transformations (DOT) on programmable logic integrated circuits (PLIC) of FPGA class. The basic and the most "slow" operation during DOT performance is the operation of multiplying by a constant factor (constant) - OMC.

  9. Efficient digitalization method for dental restorations using micro-CT data.

    Science.gov (United States)

    Kim, Changhwan; Baek, Seung Hoon; Lee, Taewon; Go, Jonggun; Kim, Sun Young; Cho, Seungryong

    2017-03-15

    The objective of this study was to demonstrate the feasibility of using micro-CT scan of dental impressions for fabricating dental restorations and to compare the dimensional accuracy of dental models generated from various methods. The key idea of the proposed protocol is that dental impression of patients can be accurately digitized by micro-CT scan and that one can make digital cast model from micro-CT data directly. As air regions of the micro-CT scan data of dental impression are equivalent to the real teeth and surrounding structures, one can segment the air regions and fabricate digital cast model in the STL format out of them. The proposed method was validated by a phantom study using a typodont with prepared teeth. Actual measurement and deviation map analysis were performed after acquiring digital cast models for each restoration methods. Comparisons of the milled restorations were also performed by placing them on the prepared teeth of typodont. The results demonstrated that an efficient fabrication of precise dental restoration is achievable by use of the proposed method.

  10. A new digitized reverse correction method for hypoid gears based on a one-dimensional probe

    Science.gov (United States)

    Li, Tianxing; Li, Jubo; Deng, Xiaozhong; Yang, Jianjun; Li, Genggeng; Ma, Wensuo

    2017-12-01

    In order to improve the tooth surface geometric accuracy and transmission quality of hypoid gears, a new digitized reverse correction method is proposed based on the measurement data from a one-dimensional probe. The minimization of tooth surface geometrical deviations is realized from the perspective of mathematical analysis and reverse engineering. Combining the analysis of complex tooth surface generation principles and the measurement mechanism of one-dimensional probes, the mathematical relationship between the theoretical designed tooth surface, the actual machined tooth surface and the deviation tooth surface is established, the mapping relation between machine-tool settings and tooth surface deviations is derived, and the essential connection between the accurate calculation of tooth surface deviations and the reverse correction method of machine-tool settings is revealed. Furthermore, a reverse correction model of machine-tool settings is built, a reverse correction strategy is planned, and the minimization of tooth surface deviations is achieved by means of the method of numerical iterative reverse solution. On this basis, a digitized reverse correction system for hypoid gears is developed by the organic combination of numerical control generation, accurate measurement, computer numerical processing, and digitized correction. Finally, the correctness and practicability of the digitized reverse correction method are proved through a reverse correction experiment. The experimental results show that the tooth surface geometric deviations meet the engineering requirements after two trial cuts and one correction.

  11. Efficient digitalization method for dental restorations using micro-CT data

    Science.gov (United States)

    Kim, Changhwan; Baek, Seung Hoon; Lee, Taewon; Go, Jonggun; Kim, Sun Young; Cho, Seungryong

    2017-03-01

    The objective of this study was to demonstrate the feasibility of using micro-CT scan of dental impressions for fabricating dental restorations and to compare the dimensional accuracy of dental models generated from various methods. The key idea of the proposed protocol is that dental impression of patients can be accurately digitized by micro-CT scan and that one can make digital cast model from micro-CT data directly. As air regions of the micro-CT scan data of dental impression are equivalent to the real teeth and surrounding structures, one can segment the air regions and fabricate digital cast model in the STL format out of them. The proposed method was validated by a phantom study using a typodont with prepared teeth. Actual measurement and deviation map analysis were performed after acquiring digital cast models for each restoration methods. Comparisons of the milled restorations were also performed by placing them on the prepared teeth of typodont. The results demonstrated that an efficient fabrication of precise dental restoration is achievable by use of the proposed method.

  12. Improved Method of Detection Falsification Results the Digital Image in Conditions of Attacks

    Directory of Open Access Journals (Sweden)

    Kobozeva A.A.

    2016-08-01

    Full Text Available The modern level of information technologies development has led to unheard ease embodiments hitherto unauthorized modifications of digital content. At the moment, very important question is the effective expert examination of authenticity of digital images, video, audio, development of the methods for identification and localization of violations of their integrity using these contents for purposes other than entertainment. Present paper deals with the improvement of the detection method of the cloning results in digital images - one of the most frequently used in the software tools falsification realized in all modern graphics editors. The method is intended for clone detection areas and pre-image in terms of additional disturbing influences in the image after the cloning operation for "masking" of the results, which complicates the search process. The improvement is aimed at reducing the number of "false alarms", when the area of the clone / pre-image detected in the original image or the localization of the identified areas do not correspond to the real clone and pre-image. The proposed improvement, based on analysis of different sizes per-pixel image blocks with the least difference from each other, has made it possible efficient functioning of the method, regardless of the specificity of the analyzed digital image.

  13. A Method for Identifying Contours in Processing Digital Images from Computer Tomograph

    Science.gov (United States)

    Roşu, Şerban; Pater, Flavius; Costea, Dan; Munteanu, Mihnea; Roşu, Doina; Fratila, Mihaela

    2011-09-01

    The first step in digital processing of two-dimensional computed tomography images is to identify the contour of component elements. This paper deals with the collective work of specialists in medicine and applied mathematics in computer science on elaborating new algorithms and methods in medical 2D and 3D imagery.

  14. On the boundary conditions and optimization methods in integrated digital image correlation

    NARCIS (Netherlands)

    Kleinendorst, S.M.; Verhaegh, B.J.; Hoefnagels, J.P.M.; Ruybalid, A.; van der Sluis, O.; Geers, M.G.D.; Lamberti, L.; Lin, M.-T.; Furlong, C.; Sciammarella, C.

    2018-01-01

    In integrated digital image correlation (IDIC) methods attention must be paid to the influence of using a correct geometric and material model, but also to make the boundary conditions in the FE simulation match the real experiment. Another issue is the robustness and convergence of the IDIC

  15. Understanding University Students' Thoughts and Practices about Digital Citizenship: A Mixed Methods Study

    Science.gov (United States)

    Kara, Nuri

    2018-01-01

    The purpose of this study was to investigate university students' thoughts and practices concerning digital citizenship. An explanatory mixed methods design was used, and it involved collecting qualitative data after a quantitative phase in order to follow up on the quantitative data in more depth. In the first quantitative phase of the study, a…

  16. A non-iterative twin image elimination method with two in-line digital holograms

    Science.gov (United States)

    Kim, Jongwu; Lee, Heejung; Jeon, Philjun; Kim, Dug Young

    2018-02-01

    We propose a simple non-iterative in-line holographic measurement method which can effectively eliminate a twin image in digital holographic 3D imaging. It is shown that a twin image can be effectively eliminated with only two measured holograms by using a simple numerical propagation algorithm and arithmetic calculations.

  17. DIGITAL DETECTION SYSTEM DESIGN OF MYCOBACTERIUM TUBERCULOSIS THROUGH EXTRACTION OF SPUTUM IMAGE USING NEURAL NETWORK METHOD

    Directory of Open Access Journals (Sweden)

    Franky Arisgraha

    2012-01-01

    Full Text Available Tuberculosis (TBC is an dangerous disease and many people has been infected. One of many important steps to control TBC effectively and efficiently is by increasing case finding using right method and accurate diagnostic. One of them is to detect Mycobacterium Tuberculosis inside sputum. Conventional detection of Mycobacterium Tuberculosis inside sputum can need a lot of time, so digitally detection method of Mycobacterium Tuberculosis was designed as an effort to get better result of detection. This method was designed by using combination between digital image processing method and Neural Network method. From testing report that was done, Mycobacterium can be detected with successful value reach 77.5% and training error less than 5%.

  18. Accelerated H-LBP-based edge extraction method for digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Shuang; Zhao, Chen-yi; Huang, Ji-peng [School of Physics, Northeast Normal University, Changchun 130024 (China); Sun, Jia-ning, E-mail: sunjn118@nenu.edu.cn [School of Mathematics and Statistics, Northeast Normal University, Changchun 130024 (China)

    2015-01-11

    With the goal of achieving real time and efficient edge extraction for digital radiography, an accelerated H-LBP-based edge extraction method (AH-LBP) is presented in this paper by improving the existing framework of local binary pattern with the H function (H-LBP). Since the proposed method avoids computationally expensive operations with no loss of quality, it possesses much lower computational complexity than H-LBP. Experimental results on real radiographies show desirable performance of our method. - Highlights: • An accelerated H-LBP method for edge extraction on digital radiography is proposed. • The novel AH-LBP relies on numerical analysis of the existing H-LBP method. • Aiming at accelerating, H-LBP is reformulated as a direct binary processing. • AH-LBP provides the same edge extraction result as H-LBP does. • AH-LBP has low computational complexity satisfying real time requirements.

  19. Full Digital Short Circuit Protection for Advanced IGBTs

    OpenAIRE

    谷村, 拓哉; 湯浅, 一史; 大村, 一郎

    2011-01-01

    A full digital short circuit protection method for advanced IGBTs has been proposed and experimentally demonstrated for the first time. The method employs combination of digital circuit, the gate charge sense instead of the conventional sense IGBT and analog circuit configuration. Digital protection scheme has significant advantages in thevprotection speed and flexibility.

  20. Synchronization method of digital pulse power supply for heavy ions accelerator in Lanzhou

    International Nuclear Information System (INIS)

    Wang Rongkun; Zhao Jiang; Wu Fengjun; Zhang Huajian; Chen Youxin; Huang Yuzhen; Gao Daqing; Zhou Zhongzu; Yan Huaihai; Yan Hongbin

    2013-01-01

    The performance of the synchrotron depends on its synchronization. A kind of synchronization method of digital pulse power supply in Heavy Ion Research Facility in Lanzhou-Cooler Storage Ring (HIRFL-CSR) was presented in detail, which is a kind of system on a programmable chip (SOPC) based on optical fiber and optical-custom component. The test of the digital power supply was performed and the current wave forms of pulse mode were given. The results show that all targets can meet the design requirements. (authors)

  1. Method for Lumped Parameter simulation of Digital Displacement pumps/motors based on CFD

    DEFF Research Database (Denmark)

    Rømer, Daniel; Johansen, Per; Pedersen, Henrik C.

    2013-01-01

    Digital displacement fluid power pumps/motors offers improved efficiency and performance compared to traditional variable displacement pump/motors. These improvements are made possible by using efficient electronically controlled seat valves and careful design of the flow geometry. To optimize...... the design and control of digital displacement machines, there is a need for simulation models, preferably models with low computational cost. Therefore, a low computational cost generic lumped parameter model of digital displacement machine is presented, including a method for determining the needed model...... parameters based on steady CFD results, in order to take detailed geometry information into account. The response of the lumped parameter model is compared to a computational expensive transient CFD model for an example geometry....

  2. A Double Perturbation Method for Reducing Dynamical Degradation of the Digital Baker Map

    Science.gov (United States)

    Liu, Lingfeng; Lin, Jun; Miao, Suoxia; Liu, Bocheng

    2017-06-01

    The digital Baker map is widely used in different kinds of cryptosystems, especially for image encryption. However, any chaotic map which is realized on the finite precision device (e.g. computer) will suffer from dynamical degradation, which refers to short cycle lengths, low complexity and strong correlations. In this paper, a novel double perturbation method is proposed for reducing the dynamical degradation of the digital Baker map. Both state variables and system parameters are perturbed by the digital logistic map. Numerical experiments show that the perturbed Baker map can achieve good statistical and cryptographic properties. Furthermore, a new image encryption algorithm is provided as a simple application. With a rather simple algorithm, the encrypted image can achieve high security, which is competitive to the recently proposed image encryption algorithms.

  3. Comparison of the analog and digital pulse-shaping methods in signal processing in nuclear detections

    International Nuclear Information System (INIS)

    Golnabi, H.

    2002-01-01

    The goal of this article is to describe the potential applications of the new improved digital techniques and provide a meaningful figure of merit for the comparison of the analog and digital methods. The experimental operation of a typical digital pulse shaper used in a spectrometer with the 23 Na source and a Ge y-ray detector is discussed. The effect of different imposed dead time on the counted pulses is investigated. It is noticed that nuclear events distribution in all ranges of dead time does not obey Poisson's law and deviation from this distribution depends on the counting rate. For a given dead time, deviation from this distribution increases linearly by increasing imposed dead time. For a fixed dead time, when counting rate increases deviation from Poisson's distribution law increases accordingly, and vice versa. (Author)

  4. Photon detector configured to employ the Gunn effect and method of use

    Science.gov (United States)

    Cich, Michael J

    2015-03-17

    Embodiments disclosed herein relate to photon detectors configured to employ the Gunn effect for detecting high-energy photons (e.g., x-rays and gamma rays) and methods of use. In an embodiment, a photon detector for detecting high-energy photons is disclosed. The photon detector includes a p-i-n semiconductor diode having a p-type semiconductor region, an n-type semiconductor region, and a compensated i-region disposed between the p-type semiconductor region and the n-type semiconductor region. The compensated i-region and has a width of about 100 .mu.m to about 400 .mu.m and is configured to exhibit the Gunn effect when the p-i-n semiconductor diode is forward biased a sufficient amount. The compensated i-region is doped to include a free carrier concentration of less than about 10.sup.10 cm.sup.-3.

  5. Uncertainty analysis of nonlinear systems employing the first-order reliability method

    International Nuclear Information System (INIS)

    Choi, Chan Kyu; Yoo, Hong Hee

    2012-01-01

    In most mechanical systems, properties of the system elements have uncertainties due to several reasons. For example, mass, stiffness coefficient of a spring, damping coefficient of a damper or friction coefficients have uncertain characteristics. The uncertain characteristics of the elements have a direct effect on the system performance uncertainty. It is very important to estimate the performance uncertainty since the performance uncertainty is directly related to manufacturing yield and consumer satisfaction. Due to this reason, the performance uncertainty should be estimated accurately and considered in the system design. In this paper, performance measures are defined for nonlinear vibration systems and the performance measure uncertainties are estimated employing the first order reliability method (FORM). It was found that the FORM could provide good results in spite of the system nonlinear characteristics. Comparing to the results obtained by Monte Carlo Simulation (MCS), the accuracy of the uncertainty analysis results obtained by the FORM is validated

  6. Digital game based learning: A new method in teaching and learning mathematics

    Science.gov (United States)

    Hussain, Sayed Yusoff bin Syed; Hoe, Tan Wee; Idris, Muhammad Zaffwan bin

    2017-05-01

    Digital game-based learning (DGBL) had been regarded as a sound learning strategy in raising pupils' willingness and interest in many disciplines. Normally, video and digital games are used in the teaching and learning mathematics. based on literature, digital games have proven its capability in making pupils motivated and are more likely to contribute to effective learning mathematics. Hence this research aims to construct a DGBL in the teaching of Mathematics for Year 1 pupils. Then, a quasi-experimental study was carried out in a school located in Gua Musang, Kelantan, involving 39 pupils. Specifically, this article tests the effectiveness of the use of DGBL in the teaching of the topic Addition of Less than 100 on pupil's achievement. This research employed a quasi-experiment, Pre and Post Test of Non-equivalent Control Group design. The data were analysed using the Nonparametric test namely the Mann-Whitney U. The research finding shows the use of the DGBL could increase the pupils' achievement in the topic of Addition of Less than 100. In practice, this research indicates that the DBGL can utilized as an alternative reference strategy for Mathematics teacher.

  7. Color quality improvement of reconstructed images in color digital holography using speckle method and spectral estimation

    Science.gov (United States)

    Funamizu, Hideki; Onodera, Yusei; Aizu, Yoshihisa

    2018-05-01

    In this study, we report color quality improvement of reconstructed images in color digital holography using the speckle method and the spectral estimation. In this technique, an object is illuminated by a speckle field and then an object wave is produced, while a plane wave is used as a reference wave. For three wavelengths, the interference patterns of two coherent waves are recorded as digital holograms on an image sensor. Speckle fields are changed by moving a ground glass plate in an in-plane direction, and a number of holograms are acquired to average the reconstructed images. After the averaging process of images reconstructed from multiple holograms, we use the Wiener estimation method for obtaining spectral transmittance curves in reconstructed images. The color reproducibility in this method is demonstrated and evaluated using a Macbeth color chart film and staining cells of onion.

  8. Radiological study of the chest using the digital method (FCR 101)

    International Nuclear Information System (INIS)

    Ferri, G.; Battolla, L.; Palla, L.; D'Alessandro, F.; Torri, T.; Tagliagambe, A.

    1991-01-01

    A computed radiography system with solid state detectors (FCR 101) was employed to evaluate the quality of digital images, with optimal and progressively lowered doses, in the study of the chest. Routine chest radiographs of in patients with no pathologic conditions of the chest were studied. The patients were divided into 3 groups: each patient in group A underwent two radiographs, one at 100% andthe other at 50% exposure; patients in group B were imaged with 100% and 25% doses, and those in group C received 50% and 25% exposure. Several parameters were employed for image evaluation, and a value was given to each of them (1=good, 2=sufficient, 3=insufficient). Upon comparison of the average values obtained, we observed that the digital technique allowed a most accurate and well-defined representation of the examined parameters at 100% exposure dose and that a 50% reduction did not decrease the informative content of the least. A 25% reduction, however, determined a high degree of background noise and a subsequent, though slight, loss of information

  9. COMPARISON OF TWO SIMPLIFICATION METHODS FOR SHORELINE EXTRACTION FROM DIGITAL ORTHOPHOTO IMAGES

    Directory of Open Access Journals (Sweden)

    B. Bayram

    2017-11-01

    Full Text Available The coastal ecosystems are very sensitive to external influences. Coastal resources such as sand dunes, coral reefs and mangroves has vital importance to prevent coastal erosion. Human based effects also threats the coastal areas. Therefore, the change of coastal areas should be monitored. Up-to-date, accurate shoreline information is indispensable for coastal managers and decision makers. Remote sensing and image processing techniques give a big opportunity to obtain reliable shoreline information. In the presented study, NIR bands of seven 1:5000 scaled digital orthophoto images of Riga Bay-Latvia have been used. The Object-oriented Simple Linear Clustering method has been utilized to extract shoreline of Riga Bay. Bend and Douglas-Peucker methods have been used to simplify the extracted shoreline to test the effect of both methods. Photogrammetrically digitized shoreline has been taken as reference data to compare obtained results. The accuracy assessment has been realised by Digital Shoreline Analysis tool. As a result, the achieved shoreline by the Bend method has been found closer to the extracted shoreline with Simple Linear Clustering method.

  10. Comparison of Two Simplification Methods for Shoreline Extraction from Digital Orthophoto Images

    Science.gov (United States)

    Bayram, B.; Sen, A.; Selbesoglu, M. O.; Vārna, I.; Petersons, P.; Aykut, N. O.; Seker, D. Z.

    2017-11-01

    The coastal ecosystems are very sensitive to external influences. Coastal resources such as sand dunes, coral reefs and mangroves has vital importance to prevent coastal erosion. Human based effects also threats the coastal areas. Therefore, the change of coastal areas should be monitored. Up-to-date, accurate shoreline information is indispensable for coastal managers and decision makers. Remote sensing and image processing techniques give a big opportunity to obtain reliable shoreline information. In the presented study, NIR bands of seven 1:5000 scaled digital orthophoto images of Riga Bay-Latvia have been used. The Object-oriented Simple Linear Clustering method has been utilized to extract shoreline of Riga Bay. Bend and Douglas-Peucker methods have been used to simplify the extracted shoreline to test the effect of both methods. Photogrammetrically digitized shoreline has been taken as reference data to compare obtained results. The accuracy assessment has been realised by Digital Shoreline Analysis tool. As a result, the achieved shoreline by the Bend method has been found closer to the extracted shoreline with Simple Linear Clustering method.

  11. A new greedy search method for the design of digital IIR filter

    Directory of Open Access Journals (Sweden)

    Ranjit Kaur

    2015-07-01

    Full Text Available A new greedy search method is applied in this paper to design the optimal digital infinite impulse response (IIR filter. The greedy search method is based on binary successive approximation (BSA and evolutionary search (ES. The suggested greedy search method optimizes the magnitude response and the phase response simultaneously and also finds the lowest order of the filter. The order of the filter is controlled by a control gene whose value is also optimized along with the filter coefficients to obtain optimum order of designed IIR filter. The stability constraints of IIR filter are taken care of during the design procedure. To determine the trade-off relationship between conflicting objectives in the non-inferior domain, the weighting method is exploited. The proposed approach is effectively applied to solve the multiobjective optimization problems of designing the digital low-pass (LP, high-pass (HP, bandpass (BP, and bandstop (BS filters. It has been demonstrated that this technique not only fulfills all types of filter performance requirements, but also the lowest order of the filter can be found. The computational experiments show that the proposed approach gives better digital IIR filters than the existing evolutionary algorithm (EA based methods.

  12. In vivo precision of conventional and digital methods for obtaining quadrant dental impressions.

    Science.gov (United States)

    Ender, Andreas; Zimmermann, Moritz; Attin, Thomas; Mehl, Albert

    2016-09-01

    Quadrant impressions are commonly used as alternative to full-arch impressions. Digital impression systems provide the ability to take these impressions very quickly; however, few studies have investigated the accuracy of the technique in vivo. The aim of this study is to assess the precision of digital quadrant impressions in vivo in comparison to conventional impression techniques. Impressions were obtained via two conventional (metal full-arch tray, CI, and triple tray, T-Tray) and seven digital impression systems (Lava True Definition Scanner, T-Def; Lava Chairside Oral Scanner, COS; Cadent iTero, ITE; 3Shape Trios, TRI; 3Shape Trios Color, TRC; CEREC Bluecam, Software 4.0, BC4.0; CEREC Bluecam, Software 4.2, BC4.2; and CEREC Omnicam, OC). Impressions were taken three times for each of five subjects (n = 15). The impressions were then superimposed within the test groups. Differences from model surfaces were measured using a normal surface distance method. Precision was calculated using the Perc90_10 value. The values for all test groups were statistically compared. The precision ranged from 18.8 (CI) to 58.5 μm (T-Tray), with the highest precision in the CI, T-Def, BC4.0, TRC, and TRI groups. The deviation pattern varied distinctly depending on the impression method. Impression systems with single-shot capture exhibited greater deviations at the tooth surface whereas high-frame rate impression systems differed more in gingival areas. Triple tray impressions displayed higher local deviation at the occlusal contact areas of upper and lower jaw. Digital quadrant impression methods achieve a level of precision, comparable to conventional impression techniques. However, there are significant differences in terms of absolute values and deviation pattern. With all tested digital impression systems, time efficient capturing of quadrant impressions is possible. The clinical precision of digital quadrant impression models is sufficient to cover a broad variety of

  13. Three looks at users: a comparison of methods for studying digital library use. User studies, Digital libraries, Digital music libraries, Music, Information use, Information science, Contextual inquiry, Contextual design, User research, Questionnaires, Log file analysis

    Directory of Open Access Journals (Sweden)

    Mark Notess

    2004-01-01

    Full Text Available Compares three user research methods of studying real-world digital library usage within the context of the Variations and Variations2 digital music libraries at Indiana University. After a brief description of both digital libraries, each method is described and illustrated with findings from the studies. User satisfaction questionnaires were used in two studies, one of Variations (n=30 and the other of Variations2 (n=12. Second, session activity log files were examined for 175 Variations2 sessions using both quantitative and qualitative methods. The third method, contextual inquiry, is illustrated with results from field observations of four voice students' information usage patterns. The three methods are compared in terms of expertise required; time required to set up, conduct, and analyse resulting data; and the benefits derived. Further benefits are achieved with a mixed-methods approach, combining the strengths of the methods to answer questions lingering as a result of other methods.

  14. Evaluation of Teeth and Supporting Structures on Digital Radiograms using Interpolation Methods

    International Nuclear Information System (INIS)

    Koh, Kwang Joon; Chang, Kee Wan

    1999-01-01

    To determine the effect of interpolation functions when processing the digital periapical images. The digital images were obtained by Digora and CDR system on the dry skull and human subject. 3 oral radiologists evaluated the 3 portions of each processed image using 7 interpolation methods and ROC curves were obtained by trapezoidal methods. The highest Az value(0.96) was obtained with cubic spline method and the lowest Az value(0.03) was obtained with facet model method in Digora system. The highest Az value(0.79) was obtained with gray segment expansion method and the lowest Az value(0.07) was obtained with facet model method in CDR system. There was significant difference of Az value in original image between Digora and CDR system at alpha=0.05 level. There were significant differences of Az values between Digora and CDR images with cubic spline method, facet model method, linear interpolation method and non-linear interpolation method at alpha= 0.1 level.

  15. Comparative study of age estimation using dentinal translucency by digital and conventional methods

    Science.gov (United States)

    Bommannavar, Sushma; Kulkarni, Meena

    2015-01-01

    Introduction: Estimating age using the dentition plays a significant role in identification of the individual in forensic cases. Teeth are one of the most durable and strongest structures in the human body. The morphology and arrangement of teeth vary from person-to-person and is unique to an individual as are the fingerprints. Therefore, the use of dentition is the method of choice in the identification of the unknown. Root dentin translucency is considered to be one of the best parameters for dental age estimation. Traditionally, root dentin translucency was measured using calipers. Recently, the use of custom built software programs have been proposed for the same. Objectives: The present study describes a method to measure root dentin translucency on sectioned teeth using a custom built software program Adobe Photoshop 7.0 version (Adobe system Inc, Mountain View California). Materials and Methods: A total of 50 single rooted teeth were sectioned longitudinally to derive a 0.25 mm uniform thickness and the root dentin translucency was measured using digital and caliper methods and compared. The Gustafson's morphohistologic approach is used in this study. Results: Correlation coefficients of translucency measurements to age were statistically significant for both the methods (P < 0.125) and linear regression equations derived from both methods revealed better ability of the digital method to assess age. Conclusion: The custom built software program used in the present study is commercially available and widely used image editing software. Furthermore, this method is easy to use and less time consuming. The measurements obtained using this method are more precise and thus help in more accurate age estimation. Considering these benefits, the present study recommends the use of digital method to assess translucency for age estimation. PMID:25709325

  16. The modular design method for digital control systems in Japanese BWRs

    International Nuclear Information System (INIS)

    Kondoh, Y.; Motomura, A.

    1998-01-01

    Digital technology is being applied to control systems in nuclear power plants. Especially in Japanese BWRs, control systems are being digitized both in constructing plant and in retrofit of operating plants. Digital technology has many advantages compared with analog technology. However, its high performance and flexibility may result in too complicated software structure, which will cause long design time and long testing time and increase cost. In introduction of digital technology, it is most important to restrict unnecessary flexibility of software. The function of control systems can be divided in standard part and variable part. Standard function may be common to every plant while variable function should be designed for each plant. Even in current design, standard design is preserved to be reused in next application. However, this design approach is not always effective because standard function may be changed by customer and nothing is considered for variable part even if it is large. To keep reliability and reduce cost by software reuse, Toshiba adopts modular design of control software, where standard part is designed as a set of standard functional modules and variable function is designed as a complex of standard functional modules and plant unique modules. Toshiba firstly applied modular design method to fuel handling machine control system. In this application the design work has been reduced to 30 percent by reusing of functional module which was first developed in former applications. This remarkable reduction of design work has enhanced reliability with less cost. In addition, software, has been produced and tested according to the functional module. These qualified software modules will be applied to next system and will realize highest reliability and least cost. Toshiba is now planning the application of this modular design method for every digital control system. (author)

  17. Software Safety Analysis of Digital Protection System Requirements Using a Qualitative Formal Method

    International Nuclear Information System (INIS)

    Lee, Jang-Soo; Kwon, Kee-Choon; Cha, Sung-Deok

    2004-01-01

    The safety analysis of requirements is a key problem area in the development of software for the digital protection systems of a nuclear power plant. When specifying requirements for software of the digital protection systems and conducting safety analysis, engineers find that requirements are often known only in qualitative terms and that existing fault-tree analysis techniques provide little guidance on formulating and evaluating potential failure modes. A framework for the requirements engineering process is proposed that consists of a qualitative method for requirements specification, called the qualitative formal method (QFM), and a safety analysis method for the requirements based on causality information, called the causal requirements safety analysis (CRSA). CRSA is a technique that qualitatively evaluates causal relationships between software faults and physical hazards. This technique, extending the qualitative formal method process and utilizing information captured in the state trajectory, provides specific guidelines on how to identify failure modes and the relationship among them. The QFM and CRSA processes are described using shutdown system 2 of the Wolsong nuclear power plants as the digital protection system example

  18. Marginal and internal fit of zirconia copings obtained using different digital scanning methods

    Directory of Open Access Journals (Sweden)

    Lorena Oliveira PEDROCHE

    Full Text Available Abstract The objective of this study was to evaluate the marginal and internal fit of zirconia copings obtained with different digital scanning methods. A human mandibular first molar was set in a typodont with its adjacent and antagonist teeth and prepared for an all-ceramic crown. Digital impressions were made using an intraoral scanner (3Shape. Polyvinyl siloxane impressions and Type IV gypsum models were also obtained and scanned with a benchtop laboratory scanner (3Shape D700. Ten zirconia copings were fabricated for each group using CAD-CAM technology. The marginal and internal fit of the zirconia copings was assessed by the silicone replica technique. Four sections of each replica were obtained, and each section was evaluated at four points: marginal gap (MG, axial wall (AW, axio-occlusal edge (AO and centro-occlusal wall (CO, using an image analyzing software. The data were submitted to one-way ANOVA and Tukey’s test (α = 0.05. They showed statistically significant differences for MG, AO and CO. Regarding MG, intraoral scanning showed lower gap values, whereas gypsum model scanning showed higher gap values. Regarding AO and CO, intraoral digital scanning showed lower gap values. Polyvinyl siloxane impression scanning and gypsum model scanning showed higher gap values and were statistically similar. It can be concluded that intraoral digital scanning provided a lower mean gap value, in comparison with conventional impressions and gypsum casts scanned with a standard benchtop laboratory scanner.

  19. Fault-weighted quantification method of fault detection coverage through fault mode and effect analysis in digital I&C systems

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jaehyun; Lee, Seung Jun, E-mail: sjlee420@unist.ac.kr; Jung, Wondea

    2017-05-15

    Highlights: • We developed the fault-weighted quantification method of fault detection coverage. • The method has been applied to specific digital reactor protection system. • The unavailability of the module had 20-times difference with the traditional method. • Several experimental tests will be effectively prioritized using this method. - Abstract: The one of the most outstanding features of a digital I&C system is the use of a fault-tolerant technique. With an awareness regarding the importance of thequantification of fault detection coverage of fault-tolerant techniques, several researches related to the fault injection method were developed and employed to quantify a fault detection coverage. In the fault injection method, each injected fault has a different importance because the frequency of realization of every injected fault is different. However, there have been no previous studies addressing the importance and weighting factor of each injected fault. In this work, a new method for allocating the weighting to each injected fault using the failure mode and effect analysis data was proposed. For application, the fault-weighted quantification method has also been applied to specific digital reactor protection system to quantify the fault detection coverage. One of the major findings in an application was that we may estimate the unavailability of the specific module in digital I&C systems about 20-times smaller than real value when we use a traditional method. The other finding was that we can also classify the importance of the experimental case. Therefore, this method is expected to not only suggest an accurate quantification procedure of fault-detection coverage by weighting the injected faults, but to also contribute to an effective fault injection experiment by sorting the importance of the failure categories.

  20. Testing digital recursive filtering method for radiation measurement channel using pin diode detector

    International Nuclear Information System (INIS)

    Talpalariu, C. M.; Talpalariu, J.; Popescu, O.; Mocanasu, M.; Lita, I.; Visan, D. A.

    2016-01-01

    In this work we have studied a software filtering method implemented in a pulse counting computerized measuring channel using PIN diode radiation detector. In case our interest was focalized for low rate decay radiation measurement accuracies improvement and response time optimization. During works for digital mathematical algorithm development, we used a hardware radiation measurement channel configuration based on PIN diode BPW34 detector, preamplifier, filter and programmable counter, computer connected. We report measurement results using two digital recursive methods in statically and dynamically field evolution. Software for graphical input/output real time diagram representation was designed and implemented, facilitating performances evaluation between the response of fixed configuration software recursive filter and dynamically adaptive configuration recursive filter. (authors)

  1. Digital Image Stabilization Method Based on Variational Mode Decomposition and Relative Entropy

    Directory of Open Access Journals (Sweden)

    Duo Hao

    2017-11-01

    Full Text Available Cameras mounted on vehicles frequently suffer from image shake due to the vehicles’ motions. To remove jitter motions and preserve intentional motions, a hybrid digital image stabilization method is proposed that uses variational mode decomposition (VMD and relative entropy (RE. In this paper, the global motion vector (GMV is initially decomposed into several narrow-banded modes by VMD. REs, which exhibit the difference of probability distribution between two modes, are then calculated to identify the intentional and jitter motion modes. Finally, the summation of the jitter motion modes constitutes jitter motions, whereas the subtraction of the resulting sum from the GMV represents the intentional motions. The proposed stabilization method is compared with several known methods, namely, medium filter (MF, Kalman filter (KF, wavelet decomposition (MD method, empirical mode decomposition (EMD-based method, and enhanced EMD-based method, to evaluate stabilization performance. Experimental results show that the proposed method outperforms the other stabilization methods.

  2. Turbulence-cascade interaction noise using an advanced digital filter method

    OpenAIRE

    Gea Aguilera, Fernando; Gill, James; Zhang, Xin; Nodé-Langlois, Thomas

    2016-01-01

    Fan wakes interacting with outlet guide vanes is a major source of noise in modern turbofan engines. In order to study this source of noise, the current work presents two-dimensional simulations of turbulence-cascade interaction noise using a computational aeroacoustic methodology. An advanced digital filter method is used for the generation of isotropic synthetic turbulence in a linearised Euler equation solver. A parameter study is presented to assess the influence of airfoil thickness, mea...

  3. Digital Sequences and a Time Reversal-Based Impact Region Imaging and Localization Method

    Science.gov (United States)

    Qiu, Lei; Yuan, Shenfang; Mei, Hanfei; Qian, Weifeng

    2013-01-01

    To reduce time and cost of damage inspection, on-line impact monitoring of aircraft composite structures is needed. A digital monitor based on an array of piezoelectric transducers (PZTs) is developed to record the impact region of impacts on-line. It is small in size, lightweight and has low power consumption, but there are two problems with the impact alarm region localization method of the digital monitor at the current stage. The first one is that the accuracy rate of the impact alarm region localization is low, especially on complex composite structures. The second problem is that the area of impact alarm region is large when a large scale structure is monitored and the number of PZTs is limited which increases the time and cost of damage inspections. To solve the two problems, an impact alarm region imaging and localization method based on digital sequences and time reversal is proposed. In this method, the frequency band of impact response signals is estimated based on the digital sequences first. Then, characteristic signals of impact response signals are constructed by sinusoidal modulation signals. Finally, the phase synthesis time reversal impact imaging method is adopted to obtain the impact region image. Depending on the image, an error ellipse is generated to give out the final impact alarm region. A validation experiment is implemented on a complex composite wing box of a real aircraft. The validation results show that the accuracy rate of impact alarm region localization is approximately 100%. The area of impact alarm region can be reduced and the number of PZTs needed to cover the same impact monitoring region is reduced by more than a half. PMID:24084123

  4. Study of time resolution by digital methods with a DRS4 module

    Science.gov (United States)

    Du, Cheng-Ming, Du; Jin-Da, Chen; Xiu-Ling, Zhang; Yang, Hai-Bo; Cheng, Ke; Kong, Jie; Hu, Zheng-Guo; Sun, Zhi-Yu; Su, Hong; Xu, Hu-Shan

    2016-04-01

    A new Digital Pulse Processing (DPP) module has been developed, based on a domino ring sampler version 4 chip (DRS4), with good time resolution for LaBr3 detectors, and different digital timing analysis methods for processing the raw detector signals are reported. The module, composed of an eight channel DRS4 chip, was used as the readout electronics and acquisition system to process the output signals from XP20D0 photomultiplier tubes (PMTs). Two PMTs were coupled with LaBr3 scintillators and placed on opposite sides of a radioactive positron 22Na source for 511 keV γ-ray tests. By analyzing the raw data acquired by the module, the best coincidence timing resolution is about 194.7 ps (FWHM), obtained by the digital constant fraction discrimination (dCFD) method, which is better than other digital methods and analysis methods based on conventional analog systems which have been tested. The results indicate that it is a promising approach to better localize the positron annihilation in positron emission tomography (PET) with time of flight (TOF), as well as for scintillation timing measurement, such as in TOF-ΔE and TOF-E systems for particle identification, with picosecond accuracy timing measurement. Furthermore, this module is more simple and convenient than other systems. Supported by the Science Foundation of the Chinese Academy of Sciences (210340XBO), National Natural Science Foundation of China (11305233,11205222), General Program of National Natural Science Foundation of China (11475234), Specific Fund of National Key Scientific Instrument and Equipment Development Project (2011YQ12009604) and Joint Fund for Research Based on Large-Scale Scientific Facilities (U1532131).

  5. Measurement of the Young's modulus of thin or flexible specimen with digital-image correlation method

    Science.gov (United States)

    Xu, Lianyun; Hou, Zhende; Qin, Yuwen

    2002-05-01

    Because some composite material, thin film material, and biomaterial, are very thin and some of them are flexible, the classical methods for measuring their Young's moduli, by mounting extensometers on specimens, are not available. A bi-image method based on image correlation for measuring Young's moduli is developed in this paper. The measuring precision achieved is one order enhanced with general digital image correlation or called single image method. By this way, the Young's modulus of a SS301 stainless steel thin tape, with thickness 0.067mm, is measured, and the moduli of polyester fiber films, a kind of flexible sheet with thickness 0.25 mm, are also measured.

  6. New technology in dietary assessment: a review of digital methods in improving food record accuracy.

    Science.gov (United States)

    Stumbo, Phyllis J

    2013-02-01

    Methods for conducting dietary assessment in the United States date back to the early twentieth century. Methods of assessment encompassed dietary records, written and spoken dietary recalls, FFQ using pencil and paper and more recently computer and internet applications. Emerging innovations involve camera and mobile telephone technology to capture food and meal images. This paper describes six projects sponsored by the United States National Institutes of Health that use digital methods to improve food records and two mobile phone applications using crowdsourcing. The techniques under development show promise for improving accuracy of food records.

  7. A digital image-based method for determining of total acidity in red wines using acid-base titration without indicator.

    Science.gov (United States)

    Tôrres, Adamastor Rodrigues; Lyra, Wellington da Silva; de Andrade, Stéfani Iury Evangelista; Andrade, Renato Allan Navarro; da Silva, Edvan Cirino; Araújo, Mário César Ugulino; Gaião, Edvaldo da Nóbrega

    2011-05-15

    This work proposes the use of digital image-based method for determination of total acidity in red wines by means of acid-base titration without using an external indicator or any pre-treatment of the sample. Digital images present the colour of the emergent radiation which is complementary to the radiation absorbed by anthocyanines present in wines. Anthocyanines change colour depending on the pH of the medium, and from the variation of colour in the images obtained during titration, the end point can be localized with accuracy and precision. RGB-based values were employed to build titration curves, and end points were localized by second derivative curves. The official method recommends potentiometric titration with a NaOH standard solution, and sample dilution until the pH reaches 8.2-8.4. In order to illustrate the feasibility of the proposed method, titrations of ten red wines were carried out. Results were compared with the reference method, and no statistically significant difference was observed between the results by applying the paired t-test at the 95% confidence level. The proposed method yielded more precise results than the official method. This is due to the trivariate nature of the measurements (RGB), associated with digital images. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Proposing Some New Ecliptics in New Testament Studies Enabled by Digital Humanities-Based Methods

    Directory of Open Access Journals (Sweden)

    James Libby

    2016-04-01

    Full Text Available “Fragmentation” is a well-worn watchword in contemporary biblical studies. But is endless fragmentation across the traditional domains of epistemology, methodology and hermeneutics the inevitable future for the postmodern exercise of biblical scholarship? In our view, multiple factors mitigate against such a future, but two command our attention here. First, digital humanities itself, through its principled use of corpora, databases and computer-based methods, seems to be remarkably capable of producing findings with high levels of face validity (interpretive agreement across multiple hermeneutical perspectives and communities. Second, and perhaps more subversively, there is a substantial body of practitioners that, per Kearney, actively question postmodernity’s impress as the final port of call for philosophy. For these practitioners deconstruction has become both indispensable — by delegitimizing hegemonies — but, in its own way, metanarratival by stultifying all other iterative, dialectical and critical processes that have historically motivated scholarship. Sensing this impasse, Kearney (1987, pp. 43-45 proposes a reimagining that is not only critical but that also embraces ποίησις, the possibility of optimistic, creative work. Such a stance within digital humanities would affirm that poietic events emerge not only through frictions and fragmentation (e.g. Kinder and McPherson 2014, pp. xiii-xviii but also through commonalties and convergence. Our approach here will be to demonstrate such a reimagining, rather than to argue for it, using two worked examples in the Greek New Testament (GNT. Those examples – digital humanities-enabled papyrology and digital humanities-enabled statistical linguistics – demonstrate ways in which the data of the text itself can be used to interrogate our perspectives and suggest that our perspectives must remain ever open to such inquiries. We conclude with a call for digital humanities to

  9. ImageJ: A Free, Easy, and Reliable Method to Measure Leg Ulcers Using Digital Pictures.

    Science.gov (United States)

    Aragón-Sánchez, Javier; Quintana-Marrero, Yurena; Aragón-Hernández, Cristina; Hernández-Herero, María José

    2017-12-01

    Wound measurement to document the healing course of chronic leg ulcers has an important role in the management of these patients. Digital cameras in smartphones are readily available and easy to use, and taking pictures of wounds is becoming a routine in specialized departments. Analyzing digital pictures with appropriate software provides clinicians a quick, clean, and easy-to-use tool for measuring wound area. A set of 25 digital pictures of plain foot and leg ulcers was the basis of this study. Photographs were taken placing a ruler next to the wound in parallel with the healthy skin with the iPhone 6S (Apple Inc, Cupertino, CA), which has a camera of 12 megapixels using the flash. The digital photographs were visualized with ImageJ 1.45s freeware (National Institutes of Health, Rockville, MD; http://imagej.net/ImageJ ). Wound area measurement was carried out by 4 raters: head of the department, wound care nurse, physician, and medical student. We assessed intra- and interrater reliability using the interclass correlation coefficient. To determine intraobserver reliability, 2 of the raters repeated the measurement of the set 1 week after the first reading. The interrater model displayed an interclass correlation coefficient of 0.99 with 95% confidence interval of 0.999 to 1.000, showing excellent reliability. The intrarater model of both examiners showed excellent reliability. In conclusion, analyzing digital images of leg ulcers with ImageJ estimates wound area with excellent reliability. This method provides a free, rapid, and accurate way to measure wounds and could routinely be used to document wound healing in daily clinical practice.

  10. Uncertainty characterization of particle depth measurement using digital in-line holography and the hybrid method.

    Science.gov (United States)

    Gao, Jian; Guildenbecher, Daniel R; Reu, Phillip L; Chen, Jun

    2013-11-04

    In the detection of particles using digital in-line holography, measurement accuracy is substantially influenced by the hologram processing method. In particular, a number of methods have been proposed to determine the out-of-plane particle depth (z location). However, due to the lack of consistent uncertainty characterization, it has been unclear which method is best suited to a given measurement problem. In this work, depth determination accuracies of seven particle detection methods, including a recently proposed hybrid method, are systematically investigated in terms of relative depth measurement errors and uncertainties. Both synthetic and experimental holograms of particle fields are considered at conditions relevant to particle sizing and tracking. While all methods display a range of particle conditions where they are most accurate, in general the hybrid method is shown to be the most robust with depth uncertainty less than twice the particle diameter over a wide range of particle field conditions.

  11. Maternal Employment and Child Development: A Fresh Look Using Newer Methods

    Science.gov (United States)

    Hill, Jennifer L.; Waldfogel, Jane; Brooks-Gunn, Jeanne; Han, Wen-Jui

    2005-01-01

    The employment rate for mothers with young children has increased dramatically over the past 25 years. Estimating the effects of maternal employment on children's development is challenged by selection bias and the missing data endemic to most policy research. To address these issues, this study uses propensity score matching and multiple…

  12. MODEL-ORIENTED METHOD OF DESIGN IMPLEMENTATION WHEN CREATING DIGITAL FILTERS

    Directory of Open Access Journals (Sweden)

    V. Levinskyi

    2016-12-01

    Full Text Available This article discusses the example of model-oriented method of design and development of digital low-pass filters (LPF for automatic control systems (ACS. Typically, high frequency noise and disturbance attenuation is carried out by analogue LPF. However, technical implementation of analogue filters higher than the second order arouse certain difficulties related with the need of precise passive components ratings selection (resistors, capacitors. If the noise and disturbances spectral composition is known, it is possible to build digital LPF with the Nyquist frequency greater than the maximum frequency in the noise spectrum. Such possibility has appeared because of cheap, energy-efficient, high-speed 32-bit microcontrollers market entry. They have analogue signals sampling rate of 30 kHz and above. The traditional approach using the “manual” method of filter parameters calculation, obtaining their recurrence expressions and further program implementation requires high qualification and a lot of time consumption from the developer. An alternative to this approach is the model-oriented method of design (MOMD in MatLab environment when in the one environment the design of digital LPF, verificaton of its performance as a part of the ACS, generation and compilation of program codes for selected microcontroller family take place. MOMD can also be used in the designs of bandpass and bandstop filters for adaptive control systems or systems of technical diagnostics. If during the commissioning or the operation of ACS there is a need in digital LPF parameters change then this operation can be performed within half an hour. MOMD technology allows to significantly reduce the time for developing a specific product without loss of quality in its design ‘cause of extensive possibilities of MatLab development environment.

  13. Semi-automated extraction of longitudinal subglacial bedforms from digital terrain models - Two new methods

    Science.gov (United States)

    Jorge, Marco G.; Brennand, Tracy A.

    2017-07-01

    Relict drumlin and mega-scale glacial lineation (positive relief, longitudinal subglacial bedforms - LSBs) morphometry has been used as a proxy for paleo ice-sheet dynamics. LSB morphometric inventories have relied on manual mapping, which is slow and subjective and thus potentially difficult to reproduce. Automated methods are faster and reproducible, but previous methods for LSB semi-automated mapping have not been highly successful. Here, two new object-based methods for the semi-automated extraction of LSBs (footprints) from digital terrain models are compared in a test area in the Puget Lowland, Washington, USA. As segmentation procedures to create LSB-candidate objects, the normalized closed contour method relies on the contouring of a normalized local relief model addressing LSBs on slopes, and the landform elements mask method relies on the classification of landform elements derived from the digital terrain model. For identifying which LSB-candidate objects correspond to LSBs, both methods use the same LSB operational definition: a ruleset encapsulating expert knowledge, published morphometric data, and the morphometric range of LSBs in the study area. The normalized closed contour method was separately applied to four different local relief models, two computed in moving windows and two hydrology-based. Overall, the normalized closed contour method outperformed the landform elements mask method. The normalized closed contour method performed on a hydrological relief model from a multiple direction flow routing algorithm performed best. For an assessment of its transferability, the normalized closed contour method was evaluated on a second area, the Chautauqua drumlin field, Pennsylvania and New York, USA where it performed better than in the Puget Lowland. A broad comparison to previous methods suggests that the normalized relief closed contour method may be the most capable method to date, but more development is required.

  14. A Survey of tooth morphology teaching methods employed in the United Kingdom and Ireland.

    Science.gov (United States)

    Lone, M; McKenna, J P; Cryan, J F; Downer, E J; Toulouse, A

    2018-01-15

    Tooth morphology is a central component of the dental curriculum and is applicable to all dental specialities. Traditional teaching methods are being supplemented with innovative strategies to tailor teaching and accommodate the learning styles of the recent generation of students. An online survey was compiled and distributed to the staff involved in teaching tooth morphology in the United Kingdom and Ireland to assess the importance of tooth morphology in the dentistry curriculum and the methodologies employed in teaching. The results of the survey show that tooth morphology constitutes a small module in the dental curriculum. It is taught in the first 2 years of the dental curriculum but is applicable in the clinical years and throughout the dental career. Traditional teaching methods, lecture and practical, are being augmented with innovative teaching including e-learning via virtual learning environment, tooth atlas and e-books leading to blended learning. The majority of the schools teach both normal dental anatomy and morphologic variations of dental anatomy and utilise plastic teeth for practical and examination purposes. Learning the 3D aspects of tooth morphology was deemed important by most of the respondents who also agreed that tooth morphology is a difficult topic for the students. Despite being core to the dental curriculum, overall minimal time is dedicated to the delivery of tooth morphology, creating a reliance on the student to learn the material. New forms of delivery including computer-assisted learning tools should help sustain learning and previously acquired knowledge. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Explicit hydration of ammonium ion by correlated methods employing molecular tailoring approach

    Science.gov (United States)

    Singh, Gurmeet; Verma, Rahul; Wagle, Swapnil; Gadre, Shridhar R.

    2017-11-01

    Explicit hydration studies of ions require accurate estimation of interaction energies. This work explores the explicit hydration of the ammonium ion (NH4+) employing Møller-Plesset second order (MP2) perturbation theory, an accurate yet relatively less expensive correlated method. Several initial geometries of NH4+(H2O)n (n = 4 to 13) clusters are subjected to MP2 level geometry optimisation with correlation consistent aug-cc-pVDZ (aVDZ) basis set. For large clusters (viz. n > 8), molecular tailoring approach (MTA) is used for single point energy evaluation at MP2/aVTZ level for the estimation of MP2 level binding energies (BEs) at complete basis set (CBS) limit. The minimal nature of the clusters upto n ≤ 8 is confirmed by performing vibrational frequency calculations at MP2/aVDZ level of theory, whereas for larger clusters (9 ≤ n ≤ 13) such calculations are effected via grafted MTA (GMTA) method. The zero point energy (ZPE) corrections are done for all the isomers lying within 1 kcal/mol of the lowest energy one. The resulting frequencies in N-H region (2900-3500 cm-1) and in O-H stretching region (3300-3900 cm-1) are in found to be in excellent agreement with the available experimental findings for 4 ≤ n ≤ 13. Furthermore, GMTA is also applied for calculating the BEs of these clusters at coupled cluster singles and doubles with perturbative triples (CCSD(T)) level of theory with aVDZ basis set. This work thus represents an art of the possible on contemporary multi-core computers for studying explicit molecular hydration at correlated level theories.

  16. Access 3 project protocol: young people and health system navigation in the digital age: a multifaceted, mixed methods study.

    Science.gov (United States)

    Kang, Melissa; Robards, Fiona; Sanci, Lena; Steinbeck, Katharine; Jan, Stephen; Hawke, Catherine; Kong, Marlene; Usherwood, Tim

    2017-08-07

    The integration of digital technology into everyday lives of young people has become widespread. It is not known whether and how technology influences barriers and facilitators to healthcare, and whether and how young people navigate between face-to-face and virtual healthcare. To provide new knowledge essential to policy and practice, we designed a study that would explore health system access and navigation in the digital age. The study objectives are to: (1) describe experiences of young people accessing and navigating the health system in New South Wales (NSW), Australia; (2) identify barriers and facilitators to healthcare for young people and how these vary between groups; (3) describe health system inefficiencies, particularly for young people who are marginalised; (4) provide policy-relevant knowledge translation of the research data. This mixed methods study has four parts, including: (1) a cross-sectional survey of young people (12-24 years) residing in NSW, Australia; (2) a longitudinal, qualitative study of a subsample of marginalised young people (defined as young people who: identify as Aboriginal and/or Torres Strait Islander; are experiencing homelessness; identify as sexuality and/or gender diverse; are of refugee or vulnerable migrant background; and/or live in rural or remote NSW); (3) interviews with professionals; (4) a knowledge translation forum. Ethics approvals were sought and granted. Data collection commenced in March 2016 and will continue until June 2017. This study will gather practice and policy-relevant intelligence about contemporary experiences of young people and health services, with a unique focus on five different groups of marginalised young people, documenting their experiences over time. Access 3 will explore navigation around all levels of the health system, determine whether digital technology is integrated into this, and if so how, and will translate findings into policy-relevant recommendations. © Article author(s) (or

  17. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    International Nuclear Information System (INIS)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K.

    2012-01-01

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  18. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  19. Application of computer intensive data analysis methods to the analysis of digital images and spatial data

    DEFF Research Database (Denmark)

    Windfeld, Kristian

    1992-01-01

    Computer-intensive methods for data analysis in a traditional setting has developed rapidly in the last decade. The application of and adaption of some of these methods to the analysis of multivariate digital images and spatial data are explored, evaluated and compared to well established classical...... into the projection pursuit is presented. Examples from remote sensing are given. The ACE algorithm for computing non-linear transformations for maximizing correlation is extended and applied to obtain a non-linear transformation that maximizes autocorrelation or 'signal' in a multivariate image....... This is a generalization of the minimum /maximum autocorrelation factors (MAF's) which is a linear method. The non-linear method is compared to the linear method when analyzing a multivariate TM image from Greenland. The ACE method is shown to give a more detailed decomposition of the image than the MAF-transformation...

  20. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for ultrasonic test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice facilitates the interoperability of ultrasonic imaging equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E 2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E 2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, transfer and archival storage. The goal of Practice E 2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE test results on any system conforming to the DICONDE standard. Toward that end, Practice E 2339 provides a data dictionary and set of information modules that are applicable to all NDE modalities. This practice supplements Practice E 2339 by providing information object definitions, information ...

  1. Standard practice for digital imaging and communication nondestructive evaluation (DICONDE) for computed radiography (CR) test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice facilitates the interoperability of computed radiography (CR) imaging and data acquisition equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This practice is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information objec...

  2. PREFACE: I International Scientific School Methods of Digital Image Processing in Optics and Photonics

    Science.gov (United States)

    Gurov, I. P.; Kozlov, S. A.

    2014-09-01

    The first international scientific school "Methods of Digital Image Processing in Optics and Photonics" was held with a view to develop cooperation between world-class experts, young scientists, students and post-graduate students, and to exchange information on the current status and directions of research in the field of digital image processing in optics and photonics. The International Scientific School was managed by: Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University) - Saint Petersburg (Russia) Chernyshevsky Saratov State University - Saratov (Russia) National research nuclear University "MEPHI" (NRNU MEPhI) - Moscow (Russia) The school was held with the participation of the local chapters of Optical Society of America (OSA), the Society of Photo-Optical Instrumentation Engineers (SPIE) and IEEE Photonics Society. Further details, including topics, committees and conference photos are available in the PDF

  3. Comparison of n-γ discrimination by zero-crossing and digital charge comparison methods

    International Nuclear Information System (INIS)

    Wolski, D.; Moszynski, M.; Ludziejewski, T.; Johnson, A.; Klamra, W.; Skeppstedt, Oe.

    1995-01-01

    A comparative study of the n-γ discrimination done by the digital charge comparison and zero-crossing methods was carried out for a 130 mm in diameter and 130 mm high BC501A liquid scintillator coupled to a 130 mm diameter XP4512B photomultiplier. The high quality of the tested detector was reflected in a photoelectron yield of 2300±100 phe/MeV and excellent n-γ discrimination properties with energy discrimination thresholds corresponding to very low neutron (or electron) energies. The superiority of the Z/C method was demonstrated for the n-γ discrimination method alone, as well as, for the simultaneous separation by the pulse shape discrimination and the time-of-flight methods down to about 30 keV recoil electron energy. The digital charge comparison method fails for a large dynamic range of energy and its separation is weakly improved by time-of-flight method for low energies. (orig.)

  4. Emitter signal separation method based on multi-level digital channelization

    Science.gov (United States)

    Han, Xun; Ping, Yifan; Wang, Sujun; Feng, Ying; Kuang, Yin; Yang, Xinquan

    2018-02-01

    To solve the problem of emitter separation under complex electromagnetic environment, a signal separation method based on multi-level digital channelization is proposed in this paper. A two-level structure which can divide signal into different channel is designed first, after that, the peaks of different channels are tracked using the track filter and the coincident signals in time domain are separated in time-frequency domain. Finally, the time domain waveforms of different signals are acquired by reverse transformation. The validness of the proposed method is proved by experiment.

  5. 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

  6. SOCIOLOGICAL MEDIA: MAXIMIZING STUDENT INTEREST IN QUANTITATIVE METHODS VIA COLLABORATIVE USE OF DIGITAL MEDIA

    Directory of Open Access Journals (Sweden)

    Frederick T. Tucker

    2016-10-01

    Full Text Available College sociology lecturers are tasked with inspiring student interest in quantitative methods despite widespread student anxiety about the subject, and a tendency for students to relieve classroom anxiety through habitual web browsing. In this paper, the author details the results of a pedagogical program whereby students at a New York City community college used industry-standard software to design, conduct, and analyze sociological surveys of one another, with the aim of inspiring student interest in quantitative methods and enhancing technical literacy. A chi-square test of independence was performed to determine the effect of the pedagogical process on the students’ ability to discuss sociological methods unrelated to their surveys in their final papers, compared with the author’s students from the previous semester who did not undergo the pedagogical program. The relation between these variables was significant, χ 2(3, N=36 = 9.8, p = .02. Findings suggest that community college students, under lecturer supervision, with minimal prior statistical knowledge, and access to digital media can collaborate in small groups to create and conduct sociological surveys, and discuss methods and results in limited classroom time. College sociology lecturers, instead of combatting student desire to use digital media, should harness this desire to advance student mastery of quantitative methods.

  7. Methods Employed in Cytofluorometric Assessment of Eryptosis, the Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Mohamed Jemaà

    2017-09-01

    Full Text Available Suicidal erythrocyte death or eryptosis contributes to or even accounts for anemia in a wide variety of clinical conditions, such as iron deficiency, dehydration, hyperphosphatemia, vitamin D excess, chronic kidney disease (CKD, hemolytic-uremic syndrome, diabetes, hepatic failure, malignancy, arteriitis, sepsis, fever, malaria, sickle-cell disease, beta-thalassemia, Hb-C and G6PD-deficiency, Wilsons disease, as well as advanced age. Moreover, eryptosis is triggered by a myriad of xenobiotics and endogenous substances including cytotoxic drugs and uremic toxins. Eryptosis is characterized by cell membrane scrambling with phosphatidylserine exposure to the erythrocyte surface. Triggers of eryptosis include oxidative stress, hyperosmotic shock, and energy depletion. Signalling involved in the regulation of eryptosis includes Ca2+ entry, ceramide, caspases, calpain, p38 kinase, protein kinase C, Janus-activated kinase 3, casein kinase 1α, cyclin-dependent kinase 4, AMP-activated kinase, p21-activated kinase 2, cGMP-dependent protein kinase, mitogen- and stress-activated kinase MSK1/2, and ill-defined tyrosine kinases. Inhibitors of eryptosis may prevent anaemia in clinical conditions associated with enhanced eryptosis and stimulators of eryptosis may favourably influence the clinical course of malaria. Additional experimentation is required to uncover further clinical conditions with enhanced eryptosis, as well as further signalling pathways, further stimulators, and further inhibitors of eryptosis. Thus, a detailed description of the methods employed in the analysis of eryptosis may help those, who enter this exciting research area. The present synopsis describes the experimental procedures required for the analysis of phosphatidylserine exposure at the cell surface with annexin-V, cell volume with forward scatter, cytosolic Ca2+ activity ([Ca2+]i with Fluo3, oxidative stress with 2′,7′-dichlorodihydrofuorescein diacetate (DCFDA, glutathione

  8. A Study on the Improvement of Digital Periapical Images using Image Interpolation Methods

    International Nuclear Information System (INIS)

    Song, Nam Kyu; Koh, Kwang Joon

    1998-01-01

    Image resampling is of particular interest in digital radiology. When resampling an image to a new set of coordinate, there appears blocking artifacts and image changes. To enhance image quality, interpolation algorithms have been used. Resampling is used to increase the number of points in an image to improve its appearance for display. The process of interpolation is fitting a continuous function to the discrete points in the digital image. The purpose of this study was to determine the effects of the seven interpolation functions when image resampling in digital periapical images. The images were obtained by Digora, CDR and scanning of Ektaspeed plus periapical radiograms on the dry skull and human subject. The subjects were exposed to intraoral X-ray machine at 60 kVp and 70 kVp with exposure time varying between 0.01 and 0.50 second. To determine which interpolation method would provide the better image, seven functions were compared ; (1) nearest neighbor (2) linear (3) non-linear (4) facet model (5) cubic convolution (6) cubic spline (7) gray segment expansion. And resampled images were compared in terms of SNR (Signal to Noise Ratio) and MTF (Modulation Transfer Function) coefficient value. The obtained results were as follows ; 1. The highest SNR value (75.96 dB) was obtained with cubic convolution method and the lowest SNR value (72.44 dB) was obtained with facet model method among seven interpolation methods. 2. There were significant differences of SNR values among CDR, Digora and film scan (P 0.05). 4. There were significant differences of MTF coefficient values between linear interpolation method and the other six interpolation methods (P<0.05). 5. The speed of computation time was the fastest with nearest neighbor method and the slowest with non-linear method. 6. The better image was obtained with cubic convolution, cubic spline and gray segment method in ROC analysis. 7. The better sharpness of edge was obtained with gray segment expansion method

  9. A situated practice of ethics for participatory visual and digital methods in public health research and practice: a focus on digital storytelling.

    Science.gov (United States)

    Gubrium, Aline C; Hill, Amy L; Flicker, Sarah

    2014-09-01

    This article explores ethical considerations related to participatory visual and digital methods for public health research and practice, through the lens of an approach known as "digital storytelling." We begin by briefly describing the digital storytelling process and its applications to public health research and practice. Next, we explore 6 common challenges: fuzzy boundaries, recruitment and consent to participate, power of shaping, representation and harm, confidentiality, and release of materials. We discuss their complexities and offer some considerations for ethical practice. We hope this article serves as a catalyst for expanded dialogue about the need for high standards of integrity and a situated practice of ethics wherein researchers and practitioners reflexively consider ethical decision-making as part of the ongoing work of public health.

  10. Analysis Method of Common Cause Failure on Non-safety Digital Control System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eun Gse [KHNP, Daejeon (Korea, Republic of)

    2014-08-15

    The effects of common cause failure on safety digital instrumentation and control system had been considered in defense in depth analysis with safety analysis method. However, the effects of common cause failure on non-safety digital instrumentation and control system also should be evaluated. The common cause failure can be included in credible failure on the non-safety system. In the I and C architecture of nuclear power plant, many design feature has been applied for the functional integrity of control system. One of that is segmentation. Segmentation defenses the propagation of faults in the I and C architecture. Some of effects from common cause failure also can be limited by segmentation. Therefore, in this paper there are two type of failure mode, one is failures in one control group which is segmented, and the other is failures in multiple control group because that the segmentation cannot defense all effects from common cause failure. For each type, the worst failure scenario is needed to be determined, so the analysis method has been proposed in this paper. The evaluation can be qualitative when there is sufficient justification that the effects are bounded in previous safety analysis. When it is not bounded in previous safety analysis, additional analysis should be done with conservative assumptions method of previous safety analysis or best estimation method with realistic assumptions.

  11. A novel method for detecting light source for digital images forensic

    Science.gov (United States)

    Roy, A. K.; Mitra, S. K.; Agrawal, R.

    2011-06-01

    Manipulation in image has been in practice since centuries. These manipulated images are intended to alter facts — facts of ethics, morality, politics, sex, celebrity or chaos. Image forensic science is used to detect these manipulations in a digital image. There are several standard ways to analyze an image for manipulation. Each one has some limitation. Also very rarely any method tried to capitalize on the way image was taken by the camera. We propose a new method that is based on light and its shade as light and shade are the fundamental input resources that may carry all the information of the image. The proposed method measures the direction of light source and uses the light based technique for identification of any intentional partial manipulation in the said digital image. The method is tested for known manipulated images to correctly identify the light sources. The light source of an image is measured in terms of angle. The experimental results show the robustness of the methodology.

  12. An autonomous surface discontinuity detection and quantification method by digital image correlation and phase congruency

    Science.gov (United States)

    Cinar, A. F.; Barhli, S. M.; Hollis, D.; Flansbjer, M.; Tomlinson, R. A.; Marrow, T. J.; Mostafavi, M.

    2017-09-01

    Digital image correlation has been routinely used to measure full-field displacements in many areas of solid mechanics, including fracture mechanics. Accurate segmentation of the crack path is needed to study its interaction with the microstructure and stress fields, and studies of crack behaviour, such as the effect of closure or residual stress in fatigue, require data on its opening displacement. Such information can be obtained from any digital image correlation analysis of cracked components, but it collection by manual methods is quite onerous, particularly for massive amounts of data. We introduce the novel application of Phase Congruency to detect and quantify cracks and their opening. Unlike other crack detection techniques, Phase Congruency does not rely on adjustable threshold values that require user interaction, and so allows large datasets to be treated autonomously. The accuracy of the Phase Congruency based algorithm in detecting cracks is evaluated and compared with conventional methods such as Heaviside function fitting. As Phase Congruency is a displacement-based method, it does not suffer from the noise intensification to which gradient-based methods (e.g. strain thresholding) are susceptible. Its application is demonstrated to experimental data for cracks in quasi-brittle (Granitic rock) and ductile (Aluminium alloy) materials.

  13. Method for fault diagnosis of digital control systems in nuclear power plant

    International Nuclear Information System (INIS)

    Suzuki, Satoshi; Nagaoka, Yukio; Ohga, Yukiharu; Ito, Tetsuo

    1990-01-01

    This paper presents a method for localizing faulty components of control systems by replaceable parts such as print boards and cables, in a large scale plant like a nuclear power plant. Most of today's control systems form a distributed configuration including many digital controllers interconnected by data communication networks. Usually, to localize the faulty components in nuclear plant control systems, suspected faulty components are narrowed down by executing manual tests to examine whether the objects are normal or abnormal based on design documents and personnel know-how, besides the uses of self-diagnosis functions built into the control systems. In the present method, procedures of various tests including the know-how and checking of self-diagnosis functions are provided as knowledge of tests. The tests to be executed is determined by considering failure probabilities of objects, and easiness and effectiveness of testing. Then, the suspects are narrowed down sequentially based on the test result. In checking feasibility of this diagnosis method for a simulated control system, intended faults are satisfactorily localized. This method is confirmed to be practicable for diagnosis of large scale digital control systems. (author)

  14. A review on brightness preserving contrast enhancement methods for digital image

    Science.gov (United States)

    Rahman, Md Arifur; Liu, Shilong; Li, Ruowei; Wu, Hongkun; Liu, San Chi; Jahan, Mahmuda Rawnak; Kwok, Ngaiming

    2018-04-01

    Image enhancement is an imperative step for many vision based applications. For image contrast enhancement, popular methods adopt the principle of spreading the captured intensities throughout the allowed dynamic range according to predefined distributions. However, these algorithms take little or no consideration into account of maintaining the mean brightness of the original scene, which is of paramount importance to carry the true scene illumination characteristics to the viewer. Though there have been significant amount of reviews on contrast enhancement methods published, updated review on overall brightness preserving image enhancement methods is still scarce. In this paper, a detailed survey is performed on those particular methods that specifically aims to maintain the overall scene illumination characteristics while enhancing the digital image.

  15. Residual stresses measurement by using ring-core method and 3D digital image correlation technique

    International Nuclear Information System (INIS)

    Hu, Zhenxing; Xie, Huimin; Zhu, Jianguo; Wang, Huaixi; Lu, Jian

    2013-01-01

    Ring-core method/three-dimensional digital image correlation (3D DIC) residual stresses measurement is proposed. Ring-core cutting is a mechanical stress relief method, and combining with 3D DIC system the deformation of the specimen surface can be measured. An optimization iteration method is proposed to obtain the residual stress and rigid-body motion. The method has the ability to cut an annular trench at a different location out of the field of view. A compression test is carried out to demonstrate how residual stress is determined by using 3D DIC system and outfield measurement. The results determined by the approach are in good agreement with the theoretical value. Ring-core/3D DIC has shown its robustness to determine residual stress and can be extended to application in the engineering field. (paper)

  16. In vivo precision of conventional and digital methods of obtaining complete-arch dental impressions

    OpenAIRE

    Ender, Andreas; Attin, Thomas; Mehl, Albert

    2016-01-01

    STATEMENT OF PROBLEM: Digital impression systems have undergone significant development in recent years, but few studies have investigated the accuracy of the technique in vivo, particularly compared with conventional impression techniques. PURPOSE: The purpose of this in vivo study was to investigate the precision of conventional and digital methods for complete-arch impressions. MATERIAL AND METHODS: Complete-arch impressions were obtained using 5 conventional (polyether, POE; vinylsilox...

  17. Comparison of various filtering methods for digital X-ray image processing

    International Nuclear Information System (INIS)

    Pfluger, T.; Reinfelder, H.E.; Dorschky, K.; Oppelt, A.; Siemens A.G., Erlangen

    1987-01-01

    Three filtering methods are explained and compared that are used for border edge enhancement of digitally processed X-ray images. The filters are compared by two examples, a radiograph of the chest, and one of the knee joint. The unsharpness mask is found to yield the best compromise between edge enhancement and image noise intensifying effect, whereas the results obtained by the high-pass filter or the Wallis filter are less good for diagnostic evaluation. The filtered images better display narrow lines, structural borders and edges, and finely spotted areas, than the original radiograph, so that diagnostic evaluation is easier after image filtering. (orig.) [de

  18. Radiation exposure in X-ray angiography and comparisons between digital and conventional methods of imaging

    International Nuclear Information System (INIS)

    Schaberg, J.

    1987-01-01

    The more recent developments and techniques in the field of angiography are examined for associated radiation exposure risks for patients and investigators and then compared to the conventional methods of angiography. It could be shown that digital subtraction angiography is generally associated with a lesser risk of somatic exposure of the patient, provided that the equipment used offers an adjustable useful-beam range and focus. The fact that above-table X-ray tubes are now generally replaced with X-ray systems installed under the examination table permits the relatively high doses, to which investigators are exposed during angiography, to be reduced by a factor of 3. (DG) [de

  19. Neutron-Gamma Pulse Shape Discrimination With Ne-213 Liquid Scintillator By Using Digital Signal Processing Combined With Similarity Method

    International Nuclear Information System (INIS)

    Mardiyanto

    2008-01-01

    Neutron-Gamma Pulse Shape Discrimination with a NE-213 Liquid Scintillator by Using Digital Signal Processing Combined with Similarity Method. Measurement of mixed neutron-gamma radiation is difficult because a nuclear detector is usually sensitive to both radiations. A new attempt of neutron-gamma pulse shape discrimination for a NE-213 liquid scintillator is presented by using digital signal processing combined with an off-line similarity method. The output pulse shapes are digitized with a high speed digital oscilloscope. The n-γ discrimination is done by calculating the index of each pulse shape, which is determined by the similarity method, and then fusing it with its corresponding pulse height. Preliminary results demonstrate good separation of neutron and gamma-ray signals from a NE-213 scintillator with a simple digital system. The results were better than those with a conventional rise time method. Figure of Merit is used to determine the quality of discrimination. The figure of merit of the discrimination using digital signal processing combined with off-line similarity method are 1.9; 1.7; 1.1; 1.1; and 0.8; on the other hand by using conventional method the rise time are 0.9; 0.9; 0.9; 0.7; and 0.4 for the equivalent electron energy of 800; 278; 139; 69; and 30 keV. (author)

  20. An Analog-Digital Mixed Measurement Method of Inductive Proximity Sensor

    Directory of Open Access Journals (Sweden)

    Yi-Xin Guo

    2015-12-01

    Full Text Available Inductive proximity sensors (IPSs are widely used in position detection given their unique advantages. To address the problem of temperature drift, this paper presents an analog-digital mixed measurement method based on the two-dimensional look-up table. The inductance and resistance components can be separated by processing the measurement data, thus reducing temperature drift and generating quantitative outputs. This study establishes and implements a two-dimensional look-up table that reduces the online computational complexity through structural modeling and by conducting an IPS operating principle analysis. This table is effectively compressed by considering the distribution characteristics of the sample data, thus simplifying the processing circuit. Moreover, power consumption is reduced. A real-time, built-in self-test (BIST function is also designed and achieved by analyzing abnormal sample data. Experiment results show that the proposed method obtains the advantages of both analog and digital measurements, which are stable, reliable, and taken in real time, without the use of floating-point arithmetic and process-control-based components. The quantitative output of displacement measurement accelerates and stabilizes the system control and detection process. The method is particularly suitable for meeting the high-performance requirements of the aviation and aerospace fields.

  1. A novel method for contrast-to-noise ratio (CNR) evaluation of digital mammography detectors

    International Nuclear Information System (INIS)

    Baldelli, P.; Phelan, N.; Egan, G.

    2009-01-01

    The purpose of this study was to test a new, simple method of evaluating the contrast-to-noise ratio (CNR) over the entire image field of a digital detector and to compare different mammography systems. Images were taken under clinical exposure conditions for a range of simulated breast thicknesses using poly(methyl methacrylate) (PMMA). At each PMMA thickness, a second image which included an additional 0.2-mm Al sheet was also acquired. Image processing software was used to calculate the CNR in multiple regions of interest (ROI) covering the entire area of the detector in order to obtain a 'CNR image'. Five detector types were evaluated, two CsI-αSi (GE Healthcare) flat panel systems, one αSe (Hologic) flat panel system and a two generations of scanning photon counting digital detectors (Sectra). Flat panel detectors exhibit better CNR uniformity compared with the first-generation scanning photon counting detector in terms of mean pixel value variation. However, significant improvement in CNR uniformity was observed for the next-generation scanning detector. The method proposed produces a map of the CNR and a measurement of uniformity throughout the entire image field of the detector. The application of this method enables quality control measurement of individual detectors and a comparison of detectors using different technologies. (orig.)

  2. Note: A new method for directly reducing the sampling jitter noise of the digital phasemeter

    Science.gov (United States)

    Liang, Yu-Rong

    2018-03-01

    The sampling jitter noise is one non-negligible noise source of the digital phasemeter used for space gravitational wave detection missions. This note provides a new method for directly reducing the sampling jitter noise of the digital phasemeter, by adding a dedicated signal of which the frequency, amplitude, and initial phase should be pre-set. In contrast to the phase correction using the pilot-tone in the work of Burnett, Gerberding et al., Liang et al., Ales et al., Gerberding et al., and Ware et al. [M.Sc. thesis, Luleå University of Technology, 2010; Classical Quantum Gravity 30, 235029 (2013); Rev. Sci. Instrum. 86, 016106 (2015); Rev. Sci. Instrum. 86, 084502 (2015); Rev. Sci. Instrum. 86, 074501 (2015); and Proceedings of the Earth Science Technology Conference (NASA, USA, 2006)], the new method is intrinsically additive noise suppression. The experiment results validate that the new method directly reduces the sampling jitter noise without data post-processing and provides the same phase measurement noise level (10-6 rad/Hz1/2 at 0.1 Hz) as the pilot-tone correction.

  3. Pulse shape analysis based on similarity and neural network with digital-analog fusion method

    International Nuclear Information System (INIS)

    Mardiyanto, M.P.; Uritani, A.; Sakai, H.; Kawarabayashi, J.; Iguchi, T.

    2000-01-01

    Through the measurement of 22 Na γ-rays, it has been demonstrated that the correction process was well done by fusing the similarity values with the pulse heights measured by the analog system, where at least four improvements in the energy spectrum characteristics were recognized, i.e., the increase of the peak-to-valley ratio, the photopeak area, the photopeak sharpness without discarding any events, and the 1,275 keV γ-ray photopeak was seen. The use of a slow digitizer was the main problem for this method. However, it can be solved easily using a faster digitizer. The fusion method was also applied for the beta-gamma mixed spectra separation. Mixed spectra of beta-gamma of the 137 Cs- 90 Sr mixed source could be separated well. We made a comparison between the energy spectrum of 137 Cs as a result of independent measurement with the result of the separation. After being compared, both FWHM agreed quite well. However, there was a slight difference between the two spectra on the peak-to-valley ratio. This separation method is simple and useful so that it can be applied for many other similar applications. (S.Y.)

  4. Nanoscale displacement measurement by a digital nano-moire method with wavelet transformation

    International Nuclear Information System (INIS)

    Liu, C-M; Chen, L-W; Wang, C-C

    2006-01-01

    A digital nano-moire method with wavelet transformation is explored to measure nanoscale in-plane displacement fields. By applying e-beam lithography, a periodic PMMA nanostructure array is fabricated directly on the specimen and used as the specimen grating. Moire patterns are generated by overlapping the images of the PMMA specimen grating obtained from AFM scanning and the virtual reference grating produced by a digital image generating process. Then, the overlapped images are filtered by the 2D wavelet transformation (WT) to capture the target moire patterns. Existing methods, by overlapping the monitor-generated scanning lines with the image of the specimen grating, cause a mismatch problem. Previously, the carrier moire method was explored with the aim of curing the mismatch problem. Unfortunately, the carrier moire method, in addition to suffering from increased complexity of mathematical calculations, is incapable of directly obtaining the displacement field. Thus, the mismatch problem will result in inconveniences and restrictions in the practical application. Instead of using monitor-generated scanning lines, the proposed method applies the virtual reference grating, and thus puts the mismatch problem to rest. Nevertheless, the resultant moire image suffers from low contrast which, if left untreated, might distort the measurement result. Therefore, the WT, known for its sharpened abilities of characteristic and edge detection, is used to capture the target moire patterns and improve the measurement accuracy. The proposed method has been carried out in the laboratory. Experimental results have shown that the proposed method is convenient and efficient for nanoscale displacement measurement

  5. Development of Gravity Acceleration Measurement Using Simple Harmonic Motion Pendulum Method Based on Digital Technology and Photogate Sensor

    Science.gov (United States)

    Yulkifli; Afandi, Zurian; Yohandri

    2018-04-01

    Development of gravitation acceleration measurement using simple harmonic motion pendulum method, digital technology and photogate sensor has been done. Digital technology is more practical and optimizes the time of experimentation. The pendulum method is a method of calculating the acceleration of gravity using a solid ball that connected to a rope attached to a stative pole. The pendulum is swung at a small angle resulted a simple harmonic motion. The measurement system consists of a power supply, Photogate sensors, Arduino pro mini and seven segments. The Arduino pro mini receives digital data from the photogate sensor and processes the digital data into the timing data of the pendulum oscillation. The calculation result of the pendulum oscillation time is displayed on seven segments. Based on measured data, the accuracy and precision of the experiment system are 98.76% and 99.81%, respectively. Based on experiment data, the system can be operated in physics experiment especially in determination of the gravity acceleration.

  6. 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...

  7. New Methods of Stereo Encoding for FM Radio Broadcasting Based on Digital Technology

    Directory of Open Access Journals (Sweden)

    P. Stranak

    2007-12-01

    Full Text Available The article describes new methods of stereo encoding for FM radio broadcasting. Digital signal processing makes possible to construct an encoder with properties that are not attainable using conventional analog solutions. The article describes the mathematical model of the encoder, on the basis of which a specific program code for DSP was developed. The article further deals with a new method of composite clipping which does not cause impurities in the output spectrum, and at the same time preserves high separation between the left and right audio channels. The application of the new method is useful mainly where there are unwanted signal overshoots on the input of the stereo encoder, e.g., in case of signal transmission from the studio to the transmitter site through a route with psychoacoustic lossy compression of data rate.

  8. Developing a digital photography-based method for dietary analysis in self-serve dining settings.

    Science.gov (United States)

    Christoph, Mary J; Loman, Brett R; Ellison, Brenna

    2017-07-01

    Current population-based methods for assessing dietary intake, including food frequency questionnaires, food diaries, and 24-h dietary recall, are limited in their ability to objectively measure food intake. Digital photography has been identified as a promising addition to these techniques but has rarely been assessed in self-serve settings. We utilized digital photography to examine university students' food choices and consumption in a self-serve dining hall setting. Research assistants took pre- and post-photos of students' plates during lunch and dinner to assess selection (presence), servings, and consumption of MyPlate food groups. Four coders rated the same set of approximately 180 meals for inter-rater reliability analyses; approximately 50 additional meals were coded twice by each coder to assess intra-rater agreement. Inter-rater agreement on the selection, servings, and consumption of food groups was high at 93.5%; intra-rater agreement was similarly high with an average of 95.6% agreement. Coders achieved the highest rates of agreement in assessing if a food group was present on the plate (95-99% inter-rater agreement, depending on food group) and estimating the servings of food selected (81-98% inter-rater agreement). Estimating consumption, particularly for items such as beans and cheese that were often in mixed dishes, was more challenging (77-94% inter-rater agreement). Results suggest that the digital photography method presented is feasible for large studies in real-world environments and can provide an objective measure of food selection, servings, and consumption with a high degree of agreement between coders; however, to make accurate claims about the state of dietary intake in all-you-can-eat, self-serve settings, researchers will need to account for the possibility of diners taking multiple trips through the serving line. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Method for Measuring the Information Content of Terrain from Digital Elevation Models

    Directory of Open Access Journals (Sweden)

    Lujin Hu

    2015-10-01

    Full Text Available As digital terrain models are indispensable for visualizing and modeling geographic processes, terrain information content is useful for terrain generalization and representation. For terrain generalization, if the terrain information is considered, the generalized terrain may be of higher fidelity. In other words, the richer the terrain information at the terrain surface, the smaller the degree of terrain simplification. Terrain information content is also important for evaluating the quality of the rendered terrain, e.g., the rendered web terrain tile service in Google Maps (Google Inc., Mountain View, CA, USA. However, a unified definition and measures for terrain information content have not been established. Therefore, in this paper, a definition and measures for terrain information content from Digital Elevation Model (DEM, i.e., a digital model or 3D representation of a terrain’s surface data are proposed and are based on the theory of map information content, remote sensing image information content and other geospatial information content. The information entropy was taken as the information measuring method for the terrain information content. Two experiments were carried out to verify the measurement methods of the terrain information content. One is the analysis of terrain information content in different geomorphic types, and the results showed that the more complex the geomorphic type, the richer the terrain information content. The other is the analysis of terrain information content with different resolutions, and the results showed that the finer the resolution, the richer the terrain information. Both experiments verified the reliability of the measurements of the terrain information content proposed in this paper.

  10. A program for making completely balanced Latin Square designs employing a systemic method

    OpenAIRE

    Kim, Beob G; Kim, Taemin

    2010-01-01

    Animal scientists employ Latin square designs to reduce the required number of animals for detecting statistical differences in animal experiments. Randomization procedures do not balance residual effects that possibly exist in Latin square experiments. A spreadsheet-based program is available for making Latin square designs balanced for the first-order residual effects. The balance of remote residual effects may also be very important to consider when a relatively long latent period exists a...

  11. Blind Forensics of Successive Geometric Transformations in Digital Images Using Spectral Method: Theory and Applications.

    Science.gov (United States)

    Chen, Chenglong; Ni, Jiangqun; Shen, Zhaoyi; Shi, Yun Qing

    2017-06-01

    Geometric transformations, such as resizing and rotation, are almost always needed when two or more images are spliced together to create convincing image forgeries. In recent years, researchers have developed many digital forensic techniques to identify these operations. Most previous works in this area focus on the analysis of images that have undergone single geometric transformations, e.g., resizing or rotation. In several recent works, researchers have addressed yet another practical and realistic situation: successive geometric transformations, e.g., repeated resizing, resizing-rotation, rotation-resizing, and repeated rotation. We will also concentrate on this topic in this paper. Specifically, we present an in-depth analysis in the frequency domain of the second-order statistics of the geometrically transformed images. We give an exact formulation of how the parameters of the first and second geometric transformations influence the appearance of periodic artifacts. The expected positions of characteristic resampling peaks are analytically derived. The theory developed here helps to address the gap left by previous works on this topic and is useful for image security and authentication, in particular, the forensics of geometric transformations in digital images. As an application of the developed theory, we present an effective method that allows one to distinguish between the aforementioned four different processing chains. The proposed method can further estimate all the geometric transformation parameters. This may provide useful clues for image forgery detection.

  12. Automatic method for selective enhancement of different tissue densities at digital chest radiography

    International Nuclear Information System (INIS)

    McNitt-Gray, M.F.; Taira, R.K.; Eldredge, S.L.; Razavi, M.

    1991-01-01

    This paper reports that digital chest radiographs often are too bright and/or lack contrast when viewed on a video display. The authors have developed a method that can automatically provide a series of look-up tables that selectively enhance the radiographically soft or dense tissues on a digital chest radiograph. This reduces viewer interaction and improves displayed image quality. On the basis of a histogram analysis, gray-level ranges are approximated for the patient background, radiographically soft tissues, and radiographically dense tissues. A series of look-up tables is automatically created by varying the contrast in each range to achieve a level of enhancement for a selected tissue range. This is repeated for differing amounts of enhancement and for each tissue range. This allows the viewer to interactively select a tissue density range and degree of enhancement at the time of display via precalculated look-up tables. Preclinical trials in pediatric radiology using computed radiography images show that this method reduces viewer interaction and improves or maintains the displayed image quality

  13. Combination of digital signal processing methods towards an improved analysis algorithm for structural health monitoring.

    Science.gov (United States)

    Pentaris, Fragkiskos P.; Makris, John P.

    2013-04-01

    In Structural Health Monitoring (SHM) is of great importance to reveal valuable information from the recorded SHM data that could be used to predict or indicate structural fault or damage in a building. In this work a combination of digital signal processing methods, namely FFT along with Wavelet Transform is applied, together with a proposed algorithm to study frequency dispersion, in order to depict non-linear characteristics of SHM data collected in two university buildings under natural or anthropogenic excitation. The selected buildings are of great importance from civil protection point of view, as there are the premises of a public higher education institute, undergoing high use, stress, visit from academic staff and students. The SHM data are collected from two neighboring buildings that have different age (4 and 18 years old respectively). Proposed digital signal processing methods are applied to the data, presenting a comparison of the structural behavior of both buildings in response to seismic activity, weather conditions and man-made activity. Acknowledgments This work was supported in part by the Archimedes III Program of the Ministry of Education of Greece, through the Operational Program "Educational and Lifelong Learning", in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) » and is co-financed by the European Union (European Social Fund) and Greek National Fund.

  14. Novel Method for Superposing 3D Digital Models for Monitoring Orthodontic Tooth Movement.

    Science.gov (United States)

    Schmidt, Falko; Kilic, Fatih; Piro, Neltje Emma; Geiger, Martin Eberhard; Lapatki, Bernd Georg

    2018-04-18

    Quantitative three-dimensional analysis of orthodontic tooth movement (OTM) is possible by superposition of digital jaw models made at different times during treatment. Conventional methods rely on surface alignment at palatal soft-tissue areas, which is applicable to the maxilla only. We introduce two novel numerical methods applicable to both maxilla and mandible. The OTM from the initial phase of multi-bracket appliance treatment of ten pairs of maxillary models were evaluated and compared with four conventional methods. The median range of deviation of OTM for three users was 13-72% smaller for the novel methods than for the conventional methods, indicating greater inter-observer agreement. Total tooth translation and rotation were significantly different (ANOVA, p < 0.01) for OTM determined by use of the two numerical and four conventional methods. Directional decomposition of OTM from the novel methods showed clinically acceptable agreement with reference results except for vertical translations (deviations of medians greater than 0.6 mm). The difference in vertical translational OTM can be explained by maxillary vertical growth during the observation period, which is additionally recorded by conventional methods. The novel approaches are, thus, particularly suitable for evaluation of pure treatment effects, because growth-related changes are ignored.

  15. Digital photography provides a fast, reliable, and noninvasive method to estimate anthocyanin pigment concentration in reproductive and vegetative plant tissues.

    Science.gov (United States)

    Del Valle, José C; Gallardo-López, Antonio; Buide, Mª Luisa; Whittall, Justen B; Narbona, Eduardo

    2018-03-01

    Anthocyanin pigments have become a model trait for evolutionary ecology as they often provide adaptive benefits for plants. Anthocyanins have been traditionally quantified biochemically or more recently using spectral reflectance. However, both methods require destructive sampling and can be labor intensive and challenging with small samples. Recent advances in digital photography and image processing make it the method of choice for measuring color in the wild. Here, we use digital images as a quick, noninvasive method to estimate relative anthocyanin concentrations in species exhibiting color variation. Using a consumer-level digital camera and a free image processing toolbox, we extracted RGB values from digital images to generate color indices. We tested petals, stems, pedicels, and calyces of six species, which contain different types of anthocyanin pigments and exhibit different pigmentation patterns. Color indices were assessed by their correlation to biochemically determined anthocyanin concentrations. For comparison, we also calculated color indices from spectral reflectance and tested the correlation with anthocyanin concentration. Indices perform differently depending on the nature of the color variation. For both digital images and spectral reflectance, the most accurate estimates of anthocyanin concentration emerge from anthocyanin content-chroma ratio, anthocyanin content-chroma basic, and strength of green indices. Color indices derived from both digital images and spectral reflectance strongly correlate with biochemically determined anthocyanin concentration; however, the estimates from digital images performed better than spectral reflectance in terms of r 2 and normalized root-mean-square error. This was particularly noticeable in a species with striped petals, but in the case of striped calyces, both methods showed a comparable relationship with anthocyanin concentration. Using digital images brings new opportunities to accurately quantify the

  16. Method for simulating dose reduction in digital mammography using the Anscombe transformation.

    Science.gov (United States)

    Borges, Lucas R; Oliveira, Helder C R de; Nunes, Polyana F; Bakic, Predrag R; Maidment, Andrew D A; Vieira, Marcelo A C

    2016-06-01

    This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the detective quantum efficiency. The scaling process takes into account the linearity of the system and the offset of the detector elements. The inserted noise is obtained by acquiring images of a flat-field phantom at the standard radiation dose and at the simulated dose. Using the Anscombe transformation, a relationship is created between the calculated noise mask and the scaled image, resulting in a clinical mammogram with the same noise and gray level characteristics as an image acquired at the lower-radiation dose. The performance of the proposed algorithm was validated using real images acquired with an anthropomorphic breast phantom at four different doses, with five exposures for each dose and 256 nonoverlapping ROIs extracted from each image and with uniform images. The authors simulated lower-dose images and compared these with the real images. The authors evaluated the similarity between the normalized noise power spectrum (NNPS) and power spectrum (PS) of simulated images and real images acquired with the same dose. The maximum relative error was less than 2.5% for every ROI. The added noise was also evaluated by measuring the local variance in the real and simulated images. The relative average error for the local variance was smaller than 1%. A new method is proposed for simulating dose reduction in clinical mammograms. In this method, the dependency between image noise and image signal is addressed using a novel application of the Anscombe transformation. NNPS, PS, and local noise

  17. Using Case-Mix Adjustment Methods To Measure the Effectiveness of Substance Abuse Treatment: Three Examples Using Client Employment Outcomes.

    Science.gov (United States)

    Koenig, Lane; Fields, Errol L.; Dall, Timothy M.; Ameen, Ansari Z.; Harwood, Henrick J.

    This report demonstrates three applications of case-mix methods using regression analysis. The results are used to assess the relative effectiveness of substance abuse treatment providers. The report also examines the ability of providers to improve client employment outcomes, an outcome domain relatively unexamined in the assessment of provider…

  18. [Determination of the daily changes curve of nitrogen oxides in the atmosphere by digital imaging colorimetry method].

    Science.gov (United States)

    Yang, Chuan-Xiao; Sun, Xiang-Ying; Liu, Bin

    2009-06-01

    From the digital images of the red complex which resulted in the interaction of nitrite with N-(1-naphthyl) ethylenediamine dihydrochloride and P-Aminobenzene sulfonic acid, it could be seen that the solution colors obviously increased with increasing the concentration of nitrite ion. The JPEG format of the digital images was transformed into gray-scale format by origin 7.0 software, and the gray values were measured with scion image software. It could be seen that the gray values of the digital image obviously increased with increasing the concentration of nitrite ion, too. Thus a novel digital imaging colorimetric (DIC) method to determine nitrogen oxides (NO(x)) contents in air was developed. Based on the red, green and blue (RGB) tricolor theory, the principle of the digital imaging colorimetric method and the influential factors on digital imaging were discussed. The present method was successfully applied to the determination of the daily changes curve of nitrogen oxides in the atmosphere and NO2- in synthetic samples with the recovery of 97.3%-104.0%, and the relative standard deviation (RSD) was less than 5.0%. The results of the determination were consistent with those obtained by spectrophotometric method.

  19. A digital method for period measurements in a nuclear reactor; Um metodo digital para medidas de periodo em um reator nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Mundim, Sergio Gorretta

    1971-02-15

    The present paper begins by giving a theoretical treatment for the nuclear reactor period. The conventional method of measuring the period is analysed and some previously developed digital methods are described. The paper criticises the latter, pointing out some deficiencies which the proposed process is able to eliminate. All errors connected with this process are also analysed. The paper presents suitable solutions to reduce them to a minimum. The total error is found to he less than the error presented by the other methods described. A digital period meter is designed with memory resources and an automatic scaler changer. Integrated circuits specifications are used in it. Real time experiments with nuclear reactors were made in order to check te validity of the method. The data acquired were applied to a simulated digital period meter implemented in a general purpose computer. The nuclear part of the work was developed at the 'Comissao Nacional de Energia Nuclear' and the simulation work was dane at the 'Departamento de Calculo Cientifico' of COPPE, which also advised the author in the completion of this thesis. (author)

  20. A digital method for period measurements in a nuclear reactor; Um metodo digital para medidas de periodo em um reator nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Mundim, Sergio Gorretta

    1971-02-15

    The present paper begins by giving a theoretical treatment for the nuclear reactor period. The conventional method of measuring the period is analysed and some previously developed digital methods are described. The paper criticises the latter, pointing out some deficiencies which the proposed process is able to eliminate. All errors connected with this process are also analysed. The paper presents suitable solutions to reduce them to a minimum. The total error is found to he less than the error presented by the other methods described. A digital period meter is designed with memory resources and an automatic scaler changer. Integrated circuits specifications are used in it. Real time experiments with nuclear reactors were made in order to check te validity of the method. The data acquired were applied to a simulated digital period meter implemented in a general purpose computer. The nuclear part of the work was developed at the 'Comissao Nacional de Energia Nuclear' and the simulation work was dane at the 'Departamento de Calculo Cientifico' of COPPE, which also advised the author in the completion of this thesis. (author)

  1. Digital assist: A comparison of two note-taking methods (traditional vs. digital pen) for students with emotional behavioral disorders

    Science.gov (United States)

    Rody, Carlotta A.

    High school biology classes traditionally follow a lecture format to disseminate content and new terminology. With the inclusive practices of No Child Left Behind, the Common Core State Standards, and end-of-course exam requirement for high school diplomas, classes include a large range of achievement levels and abilities. Teachers assume, often incorrectly, that students come to class prepared to listen and take notes. In a standard diploma, high school biology class in a separate school for students with emotional and behavioral disorders, five students participated in a single-subject, alternating treatment design study that compared the use of regular pens and digital pens to take notes during 21 lecture sessions. Behavior measures were threefold between the two interventions: (a) quantity of notes taken per minute during lectures, (b) quantity of notes or notations taken during review pauses, and (c) percent of correct responses on the daily comprehension quizzes. The study's data indicated that two students were inclined to take more lecture notes when using the digital pen. Two students took more notes with the regular pen. One student demonstrated no difference in her performance with either pen type. Both female students took more notes per minute, on average, than the three males regardless of pen type. During the review pause, three of the five students only added notes or notations to their notes when using the regular pen. The remaining two students did not add to their notes. Quiz scores differed in favor of the regular pen. All five participants earned higher scores on quizzes given during regular pen sessions. However, the differences were minor, and recommendations are made for specific training in note-taking, the pause strategy, and digital pen fluency which may produce different results for both note-taking and quiz scores.

  2. Validation of a digital photographic method for assessment of dietary quality of school lunch sandwiches brought from home

    DEFF Research Database (Denmark)

    Sabinsky, Marianne; Toft, Ulla; Andersen, Klaus K

    2013-01-01

    Background: It is a challenge to assess children’s dietary intake. The digital photographic method (DPM) may be an objective method that can overcome some of these challenges. Objective: The aim of this study was to evaluate the validity and reliability of a DPM to assess the quality of dietary....... The lunches were photographed using a standardised DPM. From the digital images, the dietary components were estimated by a trained image analyst using weights or household measures and the dietary quality was assessed using a validated Meal Index of Dietary Quality (Meal IQ). The dietary components...... and the Meal IQ obtained from the digital images were validated against the objective weighed foods of the school lunch sandwiches. To determine interrater reliability, the digital images were evaluated by a second image analyst. Results: Correlation coefficients between the DPM and the weighed foods ranged...

  3. The Signal Validation method of Digital Process Instrumentation System on signal conditioner for SMART

    International Nuclear Information System (INIS)

    Moon, Hee Gun; Park, Sang Min; Kim, Jung Seon; Shon, Chang Ho; Park, Heui Youn; Koo, In Soo

    2005-01-01

    The function of PIS(Process Instrumentation System) for SMART is to acquire the process data from sensor or transmitter. The PIS consists of signal conditioner, A/D converter, DSP(Digital Signal Process) and NIC(Network Interface Card). So, It is fully digital system after A/D converter. The PI cabinet and PDAS(Plant Data Acquisition System) in commercial plant is responsible for data acquisition of the sensor or transmitter include RTD, TC, level, flow, pressure and so on. The PDAS has the software that processes each sensor data and PI cabinet has the signal conditioner, which is need for maintenance and test. The signal conditioner has the potentiometer to adjust the span and zero for test and maintenance. The PIS of SMART also has the signal conditioner which has the span and zero adjust same as the commercial plant because the signal conditioner perform the signal condition for AD converter such as 0∼10Vdc. But, To adjust span and zero is manual test and calibration. So, This paper presents the method of signal validation and calibration, which is used by digital feature in SMART. There are I/E(current to voltage), R/E(resistor to voltage), F/E(frequency to voltage), V/V(voltage to voltage). Etc. In this paper show only the signal validation and calibration about I/E converter that convert level, pressure, flow such as 4∼20mA into signal for AD conversion such as 0∼10Vdc

  4. Assessment method of digital Chinese dance movements based on virtual reality technology

    Science.gov (United States)

    Feng, Wei; Shao, Shuyuan; Wang, Shumin

    2008-03-01

    Virtual reality has played an increasing role in such areas as medicine, architecture, aviation, engineering science and advertising. However, in the art fields, virtual reality is still in its infancy in the representation of human movements. Based on the techniques of motion capture and reuse of motion capture data in virtual reality environment, this paper presents an assessment method in order to evaluate the quantification of dancers' basic Arm Position movements in Chinese traditional dance. In this paper, the data for quantifying traits of dance motions are defined and measured on dancing which performed by an expert and two beginners, with results indicating that they are beneficial for evaluating dance skills and distinctiveness, and the assessment method of digital Chinese dance movements based on virtual reality technology is validity and feasibility.

  5. 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

  6. Monitoring system and methods for a distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2010-01-01

    A monitoring system and methods are provided for a distributed and recoverable digital control system. The monitoring system generally comprises two independent monitoring planes within the control system. The first monitoring plane is internal to the computing units in the control system, and the second monitoring plane is external to the computing units. The internal first monitoring plane includes two in-line monitors. The first internal monitor is a self-checking, lock-step-processing monitor with integrated rapid recovery capability. The second internal monitor includes one or more reasonableness monitors, which compare actual effector position with commanded effector position. The external second monitor plane includes two monitors. The first external monitor includes a pre-recovery computing monitor, and the second external monitor includes a post recovery computing monitor. Various methods for implementing the monitoring functions are also disclosed.

  7. Method and system for redundancy management of distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2012-01-01

    A method and system for redundancy management is provided for a distributed and recoverable digital control system. The method uses unique redundancy management techniques to achieve recovery and restoration of redundant elements to full operation in an asynchronous environment. The system includes a first computing unit comprising a pair of redundant computational lanes for generating redundant control commands. One or more internal monitors detect data errors in the control commands, and provide a recovery trigger to the first computing unit. A second redundant computing unit provides the same features as the first computing unit. A first actuator control unit is configured to provide blending and monitoring of the control commands from the first and second computing units, and to provide a recovery trigger to each of the first and second computing units. A second actuator control unit provides the same features as the first actuator control unit.

  8. Use of digital computers for correction of gamma method and neutron-gamma method indications

    International Nuclear Information System (INIS)

    Lakhnyuk, V.M.

    1978-01-01

    The program for the NAIRI-S computer is described which is intended for accounting and elimination of the effect of by-processes when interpreting gamma and neutron-gamma logging indications. By means of slight corrections it is possible to use the program as a mathematical basis for logging diagram standardization by the method of multidimensional regressive analysis and estimation of rock reservoir properties

  9. Precision digital control systems

    Science.gov (United States)

    Vyskub, V. G.; Rozov, B. S.; Savelev, V. I.

    This book is concerned with the characteristics of digital control systems of great accuracy. A classification of such systems is considered along with aspects of stabilization, programmable control applications, digital tracking systems and servomechanisms, and precision systems for the control of a scanning laser beam. Other topics explored are related to systems of proportional control, linear devices and methods for increasing precision, approaches for further decreasing the response time in the case of high-speed operation, possibilities for the implementation of a logical control law, and methods for the study of precision digital control systems. A description is presented of precision automatic control systems which make use of electronic computers, taking into account the existing possibilities for an employment of computers in automatic control systems, approaches and studies required for including a computer in such control systems, and an analysis of the structure of automatic control systems with computers. Attention is also given to functional blocks in the considered systems.

  10. The Employer Perspective on Sustainable Employability in the Construction Industry

    NARCIS (Netherlands)

    Tonnon, Susanne C; van der Veen, Rozan; Westerman, Marjan J; Robroek, Suzan J W; van der Ploeg, Hidde P; Van Der Beek, Allard J.; Proper, Karin I.

    OBJECTIVE: To determine the measures employers in the construction industry take to promote sustainable employability, the barriers and facilitators that influence implementation and employer needs. METHODS: Questionnaire among 499 employers and interviews with 17 employers. RESULTS: Employers

  11. The digital history of the anglophone vocabulary of psychology: An exploration using Zipfian methods.

    Science.gov (United States)

    Benjafield, John G

    2016-05-01

    The digital humanities are being applied with increasing frequency to the analysis of historically important texts. In this study, the methods of G. K. Zipf are used to explore the digital history of the vocabulary of psychology. Zipf studied a great many phenomena, from word frequencies to city sizes, showing that they tend to have a characteristic distribution in which there are a few cases that occur very frequently and many more cases that occur very infrequently. We find that the number of new words and word senses that writers contribute to the vocabulary of psychology have such a Zipfian distribution. Moreover, those who make the most contributions, such as William James, tend also to invent new metaphorical senses of words rather than new words. By contrast, those who make the fewest contributions tend to invent entirely new words. The use of metaphor makes a text easier for a reader to understand. While the use of new words requires more effort on the part of the reader, it may lead to more precise understanding than does metaphor. On average, new words and word senses become a part of psychology's vocabulary in the time leading up to World War I, suggesting that psychology was "finding its language" (Danziger, 1997) during this period. (c) 2016 APA, all rights reserved).

  12. Digital quantification of fibrosis in liver biopsy sections: description of a new method by Photoshop software.

    Science.gov (United States)

    Dahab, Gamal M; Kheriza, Mohamed M; El-Beltagi, Hussien M; Fouda, Abdel-Motaal M; El-Din, Osama A Sharaf

    2004-01-01

    The precise quantification of fibrous tissue in liver biopsy sections is extremely important in the classification, diagnosis and grading of chronic liver disease, as well as in evaluating the response to antifibrotic therapy. Because the recently described methods of digital image analysis of fibrosis in liver biopsy sections have major flaws, including the use of out-dated techniques in image processing, inadequate precision and inability to detect and quantify perisinusoidal fibrosis, we developed a new technique in computerized image analysis of liver biopsy sections based on Adobe Photoshop software. We prepared an experimental model of liver fibrosis involving treatment of rats with oral CCl4 for 6 weeks. After staining liver sections with Masson's trichrome, a series of computer operations were performed including (i) reconstitution of seamless widefield images from a number of acquired fields of liver sections; (ii) image size and solution adjustment; (iii) color correction; (iv) digital selection of a specified color range representing all fibrous tissue in the image and; (v) extraction and calculation. This technique is fully computerized with no manual interference at any step, and thus could be very reliable for objectively quantifying any pattern of fibrosis in liver biopsy sections and in assessing the response to antifibrotic therapy. It could also be a valuable tool in the precise assessment of antifibrotic therapy to other tissue regardless of the pattern of tissue or fibrosis.

  13. Measurement of definite integral of sinusoidal signal absolute value third power using digital stochastic method

    Directory of Open Access Journals (Sweden)

    Beljić Željko

    2017-01-01

    Full Text Available In this paper a special case of digital stochastic measurement of the third power of definite integral of sinusoidal signal’s absolute value, using 2-bit AD converters is presented. This case of digital stochastic method had emerged from the need to measure power and energy of the wind. Power and energy are proportional to the third power of wind speed. Anemometer output signal is sinusoidal. Therefore an integral of the third power of sinusoidal signal is zero. Two approaches are proposed for the third power calculation of the wind speed signal. One approach is to use absolute value of sinusoidal signal (before AD conversion for which there is no need of multiplier hardware change. The second approach requires small multiplier hardware change, but input signal remains unchanged. For the second approach proposed minimal hardware change was made to calculate absolute value of the result after AD conversion. Simulations have confirmed theoretical analysis. Expected precision of wind energy measurement of proposed device is better than 0,00051% of full scale. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR32019

  14. The application of ethnographic method in the study of digital media

    Directory of Open Access Journals (Sweden)

    Amelia Capobianco

    2015-04-01

    Full Text Available Digital media raise methodological issues of some relevance. The following article tries to be a contribution to the qualitative analysis of Social Networks through the use of media ethnography. We deal with issues such as time and space and with how these dimension get transformed in digital environments; the very definition of environment and social network; an effective communication; the constant flow between online and off-line activities; the role of the “digital” researcher, his/her influence on the subjects’ actions, his/her actual competence about the media and the balance of the management of situations that cross online and off-line environments, ethics and the protection of privacy. The figure of the ethnographic researcher changes, while ethnography represents – perhaps – one of the most effective methods for a research that maintains a phenomenological basis, helping to understand the meaning and value that certain tools, used for specific purposes, can take on for the youngest users.

  15. Digital radiography of scoliosis with a scanning method: radiation dose optimization

    Energy Technology Data Exchange (ETDEWEB)

    Geijer, Haakan; Andersson, Torbjoern [Department of Radiology, Oerebro University Hospital, 701 85 Oerebro (Sweden); Verdonck, Bert [Philips Medical Systems, P.O. Box 10,000, 5680 Best (Netherlands); Beckman, Karl-Wilhelm; Persliden, Jan [Department of Medical Physics, Oerebro University Hospital, 701 85 Oerebro (Sweden)

    2003-03-01

    The aim of this study was optimization of the radiation dose-image quality relationship for a digital scanning method of scoliosis radiography. The examination is performed as a digital multi-image translation scan that is reconstructed to a single image in a workstation. Entrance dose was recorded with thermoluminescent dosimeters placed dorsally on an Alderson phantom. At the same time, kerma area product (KAP) values were recorded. A Monte Carlo calculation of effective dose was also made. Image quality was evaluated with a contrast-detail phantom and Visual Grading. The radiation dose was reduced by lowering the image intensifier entrance dose request, adjusting pulse frequency and scan speed, and by raising tube voltage. The calculated effective dose was reduced from 0.15 to 0.05 mSv with reduction of KAP from 1.07 to 0.25 Gy cm{sup 2} and entrance dose from 0.90 to 0.21 mGy. The image quality was reduced with the Image Quality Figure going from 52 to 62 and a corresponding reduction in image quality as assessed with Visual Grading. The optimization resulted in a dose reduction to 31% of the original effective dose with an acceptable reduction in image quality considering the intended use of the images for angle measurements. (orig.)

  16. Impact of end-stage kidney disease on academic achievement and employment in young adults: a mixed methods study.

    Science.gov (United States)

    Murray, Peter D; Dobbels, Fabienne; Lonsdale, Daniel C; Harden, Paul N

    2014-10-01

    Young adult kidney patients are at an important stage of development when end-stage kidney disease (ESKD) may adversely influence progress in education and employment. This study is designed to assess the impact of ESKD on education and employment outcomes in young adults. This cross-sectional study was a mixed methods design. Education and career achievements in young adults with ESKD were recorded quantitatively using a questionnaire survey (n = 57): 14 of 57 representative participants were subsequently selected for semistructured interview. Questionnaire survey was conducted in 57 young adults (median age 25): 8.8% (n = 5) were predialysis; 14.0% (n = 8) dialysis; and 78.9% (n = 45) were kidney transplant recipients. Median school-leaving age was 16 (interquartile range = 15-19). Of 57 young adults, 10 (17.5%) were still studying, 43 (75.4%) had completed education, 34 (59.7%) were employed (23 full time and 11 part time), and 19 (33.3%) were unemployed. Twenty-seven of 45 transplanted patients were employed (60.0%). Of these 27, 21 were full time (77.8%). Five of eight dialysis patients were employed: only one of eight was full-time employed (12.5%). Themes impacting on education and employment included low energy levels, time missed, loss of self-esteem, and feelings of loneliness and isolation, which may progress to depression and recreational drug use. Lack of understanding from educators and employers resulting in lost work, and career ambitions changed or limited because of dialysis. Dialysis has a major negative impact on education and reduced employment rates of young adults. There is a general lack of understanding among educators and employers of the impact of ESKD. Low energy levels, lack of self-esteem, and depression are key factors. There is a need for health care providers to recognize this issue and invest in supporting young adults with ESKD. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights

  17. Compare the user interface of digital libraries\\' websites between the developing and developed countries in content analysis method

    Directory of Open Access Journals (Sweden)

    Gholam Abbas Mousavi

    2017-03-01

    Full Text Available Purpose: This study performed with goals of determining the Items in designing and developing the user interface of digital libraries' websites and to determine the best digital libraries' websites and discuss their advantages and disadvantages; to analyze and compare digital libraries' websites in developing countries with those in the developed countries. Methodology: to do so, 50 digital libraries' websites were selected by purposive sampling method. By analyzing the level of development of the countries in the sample regarding their digital libraries' websites, 12 websites were classified as belonging to developing and 38 countries to developed counties. Then, their content was studied by using a qualitative content analysis. The study was conducted by using a research-constructed checklist containing 12 main categories and 44 items, whose validity was decided by content validity method. The data was analyzed in SPSS (version 16. Findings: The results showed that in terms of “online resources”, “library collection,” and “navigation”, there is a significant relationship between the digital library' user interface design in both types of countries. Results: The items of “online public access catalogue (OPAC” and “visits statistics” were observed in more developing countries’ digital libraries' websites. However, the item of “menu and submenus to introduce library' sections” was presented in more developed countries’ digital libraries' websites. Moreover, by analyzing the number of items in the selected websites, “American Memory” with 44 items, “International Children Digital Library” with 40 items, and “California” with 39 items were the best, and “Berkeley Sun Site” with 10 items was the worst website. Despite more and better quality digital libraries in developed countries, the quality of digital libraries websites in developing countries is considerable. In general, some of the newly established

  18. Comparison of tissue equalization, and premium view post-processing methods in full field digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Chen Baoying, E-mail: chenby128@yahoo.co [Department of Radiology, Tangdu Hospital, Fourth Military Medical University, Xinsi Road 1, 710038 Xi' an, Shaanxi (China); Wang Wei; Huang Jin; Zhao Ming; Cui Guangbin [Department of Radiology, Tangdu Hospital, Fourth Military Medical University, Xinsi Road 1, 710038 Xi' an, Shaanxi (China); Xu Jing [Cell Engineering Research Centre and Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Changle West Road 169, 710032 Xi' an, Shaanxi (China); Guo Wei; Du Pang; Li Pei [Department of Radiology, Tangdu Hospital, Fourth Military Medical University, Xinsi Road 1, 710038 Xi' an, Shaanxi (China); Yu Jun, E-mail: pclamper@163.co [Department of Preclinical Experiment Center, Fourth Military Medical University, Changle West Road 169, 710032 Xi' an, Shaanxi (China)

    2010-10-15

    Objective: To retrospectively evaluate the diagnostic abilities of 2 post-processing methods provided by GE Senographe DS system, tissue equalization (TE) and premium view (PV) in full field digital mammography (FFDM). Materials and methods: In accordance with the ethical standards of the World Medical Association, this study was approved by regional ethics committee and signed informed patient consents were obtained. We retrospectively reviewed digital mammograms from 101 women (mean age, 47 years; range, 23-81 years) in the modes of TE and PV, respectively. Three radiologists, fully blinded to the post-processing methods, all patient clinical information and histologic results, read images by using objective image interpretation criteria for diagnostic information end points such as lesion border delineation, definition of disease extent, visualization of internal and surrounding morphologic features of the lesions. Also, overall diagnostic impression in terms of lesion conspicuity, detectability and diagnostic confidence was assessed. Between-group comparisons were performed with Wilcoxon signed rank test. Results: Readers 1, 2, and 3 demonstrated significant overall better impression of PV in 29, 27, and 24 patients, compared with that for TE in 12, 13, and 11 patients, respectively (p < 0.05). Significant (p < 0.05) better impression of PV was also demonstrated for diagnostic information end points. Importantly, PV proved to be more sensitive than TE while detecting malignant lesions in dense breast rather than benign lesions and malignancy in non-dense breast (p < 0.01). Conclusion: PV compared with TE provides marked better diagnostic information in FFDM, particularly for patients with malignancy in dense breast.

  19. Comparison of tissue equalization, and premium view post-processing methods in full field digital mammography

    International Nuclear Information System (INIS)

    Chen Baoying; Wang Wei; Huang Jin; Zhao Ming; Cui Guangbin; Xu Jing; Guo Wei; Du Pang; Li Pei; Yu Jun

    2010-01-01

    Objective: To retrospectively evaluate the diagnostic abilities of 2 post-processing methods provided by GE Senographe DS system, tissue equalization (TE) and premium view (PV) in full field digital mammography (FFDM). Materials and methods: In accordance with the ethical standards of the World Medical Association, this study was approved by regional ethics committee and signed informed patient consents were obtained. We retrospectively reviewed digital mammograms from 101 women (mean age, 47 years; range, 23-81 years) in the modes of TE and PV, respectively. Three radiologists, fully blinded to the post-processing methods, all patient clinical information and histologic results, read images by using objective image interpretation criteria for diagnostic information end points such as lesion border delineation, definition of disease extent, visualization of internal and surrounding morphologic features of the lesions. Also, overall diagnostic impression in terms of lesion conspicuity, detectability and diagnostic confidence was assessed. Between-group comparisons were performed with Wilcoxon signed rank test. Results: Readers 1, 2, and 3 demonstrated significant overall better impression of PV in 29, 27, and 24 patients, compared with that for TE in 12, 13, and 11 patients, respectively (p < 0.05). Significant (p < 0.05) better impression of PV was also demonstrated for diagnostic information end points. Importantly, PV proved to be more sensitive than TE while detecting malignant lesions in dense breast rather than benign lesions and malignancy in non-dense breast (p < 0.01). Conclusion: PV compared with TE provides marked better diagnostic information in FFDM, particularly for patients with malignancy in dense breast.

  20. Increasing the computational efficient of digital cross correlation by a vectorization method

    Science.gov (United States)

    Chang, Ching-Yuan; Ma, Chien-Ching

    2017-08-01

    This study presents a vectorization method for use in MATLAB programming aimed at increasing the computational efficiency of digital cross correlation in sound and images, resulting in a speedup of 6.387 and 36.044 times compared with performance values obtained from looped expression. This work bridges the gap between matrix operations and loop iteration, preserving flexibility and efficiency in program testing. This paper uses numerical simulation to verify the speedup of the proposed vectorization method as well as experiments to measure the quantitative transient displacement response subjected to dynamic impact loading. The experiment involved the use of a high speed camera as well as a fiber optic system to measure the transient displacement in a cantilever beam under impact from a steel ball. Experimental measurement data obtained from the two methods are in excellent agreement in both the time and frequency domain, with discrepancies of only 0.68%. Numerical and experiment results demonstrate the efficacy of the proposed vectorization method with regard to computational speed in signal processing and high precision in the correlation algorithm. We also present the source code with which to build MATLAB-executable functions on Windows as well as Linux platforms, and provide a series of examples to demonstrate the application of the proposed vectorization method.

  1. Application of the digital image correlation method in the study of cohesive coarse soil deformations

    Science.gov (United States)

    Kogut, Janusz P.; Tekieli, Marcin

    2018-04-01

    Non-contact video measurement methods are used to extend the capabilities of standard measurement systems, based on strain gauges or accelerometers. In most cases, they are able to provide more accurate information about the material or construction being tested than traditional sensors, while maintaining a high resolution and measurement stability. With the use of optical methods, it is possible to generate a full field of displacement on the surface of the test sample. The displacement value is the basic (primary) value determined using optical methods, and it is possible to determine the size of the derivative in the form of a sample deformation. This paper presents the application of a non-contact optical method to investigate the deformation of coarse soil material. For this type of soil, it is particularly difficult to obtain basic strength parameters. The use of a non-contact optical method, followed by a digital image correlation (DIC) study of the sample obtained during the tests, effectively completes the description of the behaviour of this type of material.

  2. A simplified, improved method for making amplifier equivalent noise charge measurements using a new generation digitizing oscilloscope

    International Nuclear Information System (INIS)

    Zimmerman, T.

    1990-10-01

    Historically a variety of methods have been used to measure the equivalent noise charge (ENC) of amplifier/shaper systems for high energy physics. Some of these methods require several pieces of special test equipment and a fair amount of effort. The advent of digitizing oscilloscopes with statistics capabilities makes it possible to perform certain types of noise measurements accurately with very little effort. This paper describes the noise measurement method of a time invariant amplifier/shaper and of a time variant correlated sampling system, using a Tektronix DSA602 Digitizing Signal Analyzer. 4 figs

  3. Methods, media and systems for managing a distributed application running in a plurality of digital processing devices

    Science.gov (United States)

    Laadan, Oren; Nieh, Jason; Phung, Dan

    2012-10-02

    Methods, media and systems for managing a distributed application running in a plurality of digital processing devices are provided. In some embodiments, a method includes running one or more processes associated with the distributed application in virtualized operating system environments on a plurality of digital processing devices, suspending the one or more processes, and saving network state information relating to network connections among the one or more processes. The method further include storing process information relating to the one or more processes, recreating the network connections using the saved network state information, and restarting the one or more processes using the stored process information.

  4. Evaluation of a digital method to assess evening meal intake in a free-living adult population

    Directory of Open Access Journals (Sweden)

    Anne Dahl Lassen

    2010-11-01

    Full Text Available Background: In recent years new applications of technologies, including digital images, to capture dietary behaviour in real time have been explored. Objectives: To validate a digital method for estimating evening meal intake in a free-living adult population, and to examine the feasibility of the method for recording evening meal intake over a prolonged period of time. Design: The digital method was compared against weighed records of 19 participants’ usual evening meals for five consecutive days. Two trained image analysts independently estimated the weight of individual foods within the meals into major food categories, and the nutrient content was calculated. A second study included interviews with 28 participants recording their evening meals on weekdays for three consecutive weeks to get their perspective on the feasibility of the method. Results: High correlation coefficients between the digital method and weighed records were found for all measured food categories and nutrients. Comparable means and acceptable limits of agreement (mean difference +/− 2 SD were found with regard to macronutrient distribution (e.g. fat content −5 to 6 E%, energy density (−75 to 91 kJ/100 g, and energy-adjusted foods (e.g. fruit and vegetable content −241 to 236 g/10 MJ. The majority of the participants expressed satisfaction with the method and were willing to record their evening meals for 1 month or more using the digital method. Conclusion: The digital method is valid and feasible for evening meal estimation in real-time where a prolonged recording period of participants’ meals is needed.

  5. Digital Integration Method (DIM): A new method for the precise correlation of OCT and fluorescein angiography

    International Nuclear Information System (INIS)

    Hassenstein, A.; Richard, G.; Inhoffen, W.; Scholz, F.

    2007-01-01

    The new integration method (DIM) provides for the first time the anatomically precise integration of the OCT-scan position into the angiogram (fluorescein angiography, FLA), using reference marker at corresponding vessel crossings. Therefore an exact correlation of angiographic and morphological pathological findings is possible und leads to a better understanding of OCT and FLA. Occult findings in FLA were the patient group which profited most. Occult leakages could gain additional information using DIM such as serous detachment of the retinal pigment epithelium (RPE) in a topography. So far it was unclear whether the same localization in the lesion was examined by FLA and OCT especially when different staff were performing and interpreting the examination. Using DIM this problem could be solved using objective markers. This technique is the requirement for follow-up examinations by OCT. Using DIM for an objective, reliable and precise correlation of OCT and FLA-findings it is now possible to provide the identical scan-position in follow-up. Therefore for follow-up in clinical studies it is mandatory to use DIM to improve the evidence-based statement of OCT and the quality of the study. (author) [de

  6. Development of Uncertainty Analysis Method for SMART Digital Core Protection and Monitoring System

    International Nuclear Information System (INIS)

    Koo, Bon Seung; In, Wang Kee; Hwang, Dae Hyun

    2012-01-01

    The Korea Atomic Energy Research Institute has developed a system-integrated modular advanced reactor (SMART) for a seawater desalination and electricity generation. Online digital core protection and monitoring systems, called SCOPS and SCOMS respectively were developed. SCOPS calculates minimum DNBR and maximum LPD based on the several online measured system parameters. SCOMS calculates the variables of limiting conditions for operation. KAERI developed overall uncertainty analysis methodology which is used statistically combining uncertainty components of SMART core protection and monitoring system. By applying overall uncertainty factors in on-line SCOPS/SCOMS calculation, calculated LPD and DNBR are conservative with a 95/95 probability/confidence level. In this paper, uncertainty analysis method is described for SMART core protection and monitoring system

  7. 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.

  8. Correction Method of Wiener Spectrum (WS) on Digital Medical Imaging Systems

    International Nuclear Information System (INIS)

    Kim, Jung Min; Lee, Ki Sung; Kim, You Hyun

    2009-01-01

    Noise evaluation for an image has been performed by root mean square (RMS) granularity, autocorrelation function (ACF), and Wiener spectrum. RMS granularity stands for standard deviation of photon data and ACF is acquired by integration of 1 D function of distance variation. Fourier transform of ACF results in noise power spectrum which is called Wiener spectrum in image quality evaluation. Wiener spectrum represents noise itself. In addition, along with MTF, it is an important factor to produce detective quantum efficiency (DQE). The proposed evaluation method using Wiener spectrum is expected to contribute to educate the concept of Wiener spectrum in educational organizations, choose the appropriate imaging detectors for clinical applications, and maintain image quality in digital imaging systems.

  9. [Research on fractal tones generating method for tinnitus rehabilitation based on musical instrument digital interface technology].

    Science.gov (United States)

    Wang, Lu; He, Peiyu; Pan, Fan

    2014-08-01

    Tinnitus is a subjective sensation of sound without external stimulation. It has become ubiquitous and has therefore aroused much attention in recent years. According to the survey, ameliorating tinnitus based on special music and reducing pressure have good effects on the treatment of it. Meantime, vicious cycle chains between tinnitus and bad feelings have been broken. However, tinnitus therapy has been restricted by using looping music. Therefore, a method of generating fractal tones based on musical instrument digital interface (MIDI) technology and pink noise has been proposed in this paper. The experimental results showed that the fractal fragments were self-similar, incompletely reduplicate, and no sudden changes in pitches and would have a referential significance for tinnitus therapy.

  10. Method and apparatus for clockless analog-to-digital conversion and peak detection

    Science.gov (United States)

    DeGeronimo, Gianluigi

    2007-03-06

    An apparatus and method for analog-to-digital conversion and peak detection includes at least one stage, which includes a first switch, second switch, current source or capacitor, and discriminator. The discriminator changes state in response to a current or charge associated with the input signal exceeding a threshold, thereby indicating whether the current or charge associated with the input signal is greater than the threshold. The input signal includes a peak or a charge, and the converter includes a peak or charge detect mode in which a state of the switch is retained in response to a decrease in the current or charge associated with the input signal. The state of the switch represents at least a portion of a value of the peak or of the charge.

  11. Design Method for Fast Switching Seat Valves for Digital Displacement Machines

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Johansen, Per; Pedersen, Henrik C.

    2014-01-01

    corresponding to the piston movement, which has been shown to facilitate superior part load efficiency combined with high bandwidth compared to traditional displacement machines. However, DD machines need fast switching on-off valves with low pressure loss for efficient operation, especially in fast rotating......Digital Displacement (DD) machines are upcoming technology where the displacement of each pressure chamber is controlled electronically by use of two fast switching seat valves. The effective displacement and operation type (pumping/motoring) may be controlled by manipulating the seat valves...... method for DD seat valves are presented, taking into account the significant aspects related to obtaining efficient DD valves with basis in a given DD machine specifications. The seat area is minimized and the stroke length is minimized to obtain fast switching times while considering the pressure loss...

  12. A rapid method for counting nucleated erythrocytes on stained blood smears by digital image analysis

    Science.gov (United States)

    Gering, E.; Atkinson, C.T.

    2004-01-01

    Measures of parasitemia by intraerythrocytic hematozoan parasites are normally expressed as the number of infected erythrocytes per n erythrocytes and are notoriously tedious and time consuming to measure. We describe a protocol for generating rapid counts of nucleated erythrocytes from digital micrographs of thin blood smears that can be used to estimate intensity of hematozoan infections in nonmammalian vertebrate hosts. This method takes advantage of the bold contrast and relatively uniform size and morphology of erythrocyte nuclei on Giemsa-stained blood smears and uses ImageJ, a java-based image analysis program developed at the U.S. National Institutes of Health and available on the internet, to recognize and count these nuclei. This technique makes feasible rapid and accurate counts of total erythrocytes in large numbers of microscope fields, which can be used in the calculation of peripheral parasitemias in low-intensity infections.

  13. DIGITAL GEOECOLOGICAL MAPS AND SEVERAL METHODS OF ITS CONSTRUCTING IN A GIS ARCGIS

    Directory of Open Access Journals (Sweden)

    S. V. Lebedev

    2015-01-01

    Full Text Available This article is focused on methods of digital geoecological maps construction with using GIS ArcGIS technologies. The technique of GIS ArcGIS mapping is illustrated by examples of GIS maps of radioactive and chemical pollution in the snow cover on the territory of St. Petersburg’s (Russia. The geostatistic and deterministic approaches were applied for interpolation of input data. The input data were presented by the coordinates of points located on territory according to the scheme of measurements. The most optimal amount of classification intervals describing the natural processes and the phenomena of all-over distribution on the geoeclogical GIS maps is the 3–5 intervals of the parameter that will be considered. The borders of classes of intervals are set in depend on existing normative of pollution in different components of environment and empirical character of study parameter distribution on territory under consideration.

  14. 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

  15. Synthesis method for ultrananocrystalline diamond in powder employing a coaxial arc plasma gun

    Science.gov (United States)

    Naragino, Hiroshi; Tominaga, Aki; Hanada, Kenji; Yoshitake, Tsuyoshi

    2015-07-01

    A new method that enables us to synthesize ultrananocrystalline diamond (UNCD) in powder is proposed. Highly energetic carbon species ejected from a graphite cathode of a coaxial arc plasma gun were provided on a quartz plate at a high density by repeated arc discharge in a compact vacuum chamber, and resultant films automatically peeled from the plate were aggregated and powdered. The grain size was easily controlled from 2.4 to 15.0 nm by changing the arc discharge energy. It was experimentally demonstrated that the proposed method is a new and promising method that enables us to synthesize UNCD in powder easily and controllably.

  16. Synthesis method for ultrananocrystalline diamond in powder employing a coaxial arc plasma gun

    International Nuclear Information System (INIS)

    Naragino, Hiroshi; Tominaga, Aki; Yoshitake, Tsuyoshi; Hanada, Kenji

    2015-01-01

    A new method that enables us to synthesize ultrananocrystalline diamond (UNCD) in powder is proposed. Highly energetic carbon species ejected from a graphite cathode of a coaxial arc plasma gun were provided on a quartz plate at a high density by repeated arc discharge in a compact vacuum chamber, and resultant films automatically peeled from the plate were aggregated and powdered. The grain size was easily controlled from 2.4 to 15.0 nm by changing the arc discharge energy. It was experimentally demonstrated that the proposed method is a new and promising method that enables us to synthesize UNCD in powder easily and controllably. (author)

  17. Multi-level computational methods for interdisciplinary research in the HathiTrust Digital Library.

    Science.gov (United States)

    Murdock, Jaimie; Allen, Colin; Börner, Katy; Light, Robert; McAlister, Simon; Ravenscroft, Andrew; Rose, Robert; Rose, Doori; Otsuka, Jun; Bourget, David; Lawrence, John; Reed, Chris

    2017-01-01

    We show how faceted search using a combination of traditional classification systems and mixed-membership topic models can go beyond keyword search to inform resource discovery, hypothesis formulation, and argument extraction for interdisciplinary research. Our test domain is the history and philosophy of scientific work on animal mind and cognition. The methods can be generalized to other research areas and ultimately support a system for semi-automatic identification of argument structures. We provide a case study for the application of the methods to the problem of identifying and extracting arguments about anthropomorphism during a critical period in the development of comparative psychology. We show how a combination of classification systems and mixed-membership models trained over large digital libraries can inform resource discovery in this domain. Through a novel approach of "drill-down" topic modeling-simultaneously reducing both the size of the corpus and the unit of analysis-we are able to reduce a large collection of fulltext volumes to a much smaller set of pages within six focal volumes containing arguments of interest to historians and philosophers of comparative psychology. The volumes identified in this way did not appear among the first ten results of the keyword search in the HathiTrust digital library and the pages bear the kind of "close reading" needed to generate original interpretations that is the heart of scholarly work in the humanities. Zooming back out, we provide a way to place the books onto a map of science originally constructed from very different data and for different purposes. The multilevel approach advances understanding of the intellectual and societal contexts in which writings are interpreted.

  18. Method for simulating dose reduction in digital mammography using the Anscombe transformation

    International Nuclear Information System (INIS)

    Borges, Lucas R.; Oliveira, Helder C. R. de; Nunes, Polyana F.; Vieira, Marcelo A. C.; Bakic, Predrag R.; Maidment, Andrew D. A.

    2016-01-01

    Purpose: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. Methods: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the detective quantum efficiency. The scaling process takes into account the linearity of the system and the offset of the detector elements. The inserted noise is obtained by acquiring images of a flat-field phantom at the standard radiation dose and at the simulated dose. Using the Anscombe transformation, a relationship is created between the calculated noise mask and the scaled image, resulting in a clinical mammogram with the same noise and gray level characteristics as an image acquired at the lower-radiation dose. Results: The performance of the proposed algorithm was validated using real images acquired with an anthropomorphic breast phantom at four different doses, with five exposures for each dose and 256 nonoverlapping ROIs extracted from each image and with uniform images. The authors simulated lower-dose images and compared these with the real images. The authors evaluated the similarity between the normalized noise power spectrum (NNPS) and power spectrum (PS) of simulated images and real images acquired with the same dose. The maximum relative error was less than 2.5% for every ROI. The added noise was also evaluated by measuring the local variance in the real and simulated images. The relative average error for the local variance was smaller than 1%. Conclusions: A new method is proposed for simulating dose reduction in clinical mammograms. In this method, the dependency between image noise and image signal is addressed using a novel application of the Anscombe

  19. Method for simulating dose reduction in digital mammography using the Anscombe transformation

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Lucas R., E-mail: lucas.rodrigues.borges@usp.br; Oliveira, Helder C. R. de; Nunes, Polyana F.; Vieira, Marcelo A. C. [Department of Electrical and Computer Engineering, São Carlos School of Engineering, University of São Paulo, 400 Trabalhador São-Carlense Avenue, São Carlos 13566-590 (Brazil); Bakic, Predrag R.; Maidment, Andrew D. A. [Department of Radiology, Hospital of the University of Pennsylvania, University of Pennsylvania, 3400 Spruce Street, Philadelphia, Pennsylvania 19104 (United States)

    2016-06-15

    Purpose: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. Methods: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the detective quantum efficiency. The scaling process takes into account the linearity of the system and the offset of the detector elements. The inserted noise is obtained by acquiring images of a flat-field phantom at the standard radiation dose and at the simulated dose. Using the Anscombe transformation, a relationship is created between the calculated noise mask and the scaled image, resulting in a clinical mammogram with the same noise and gray level characteristics as an image acquired at the lower-radiation dose. Results: The performance of the proposed algorithm was validated using real images acquired with an anthropomorphic breast phantom at four different doses, with five exposures for each dose and 256 nonoverlapping ROIs extracted from each image and with uniform images. The authors simulated lower-dose images and compared these with the real images. The authors evaluated the similarity between the normalized noise power spectrum (NNPS) and power spectrum (PS) of simulated images and real images acquired with the same dose. The maximum relative error was less than 2.5% for every ROI. The added noise was also evaluated by measuring the local variance in the real and simulated images. The relative average error for the local variance was smaller than 1%. Conclusions: A new method is proposed for simulating dose reduction in clinical mammograms. In this method, the dependency between image noise and image signal is addressed using a novel application of the Anscombe

  20. Employing Creative Practice as a Research Method in the Field of Wearable and Interactive Technologies

    DEFF Research Database (Denmark)

    Frankjær, Raune; Flanagan, Patricia; Gilgen, Daniel

    2013-01-01

    for creative practitioners to extend their artistic expression, but a method applicable within research and development. Creative practitioners generally approach their sub- ject matter intuitively and holistically and are therefore capable of facilitating insights where rational approaches may not. Working...

  1. Technetium 99-m labeled radio-diagnostic agents employing stannous tartrate and method of preparation

    International Nuclear Information System (INIS)

    Molinski, V.J.; Wilczewski, J.A.

    1976-01-01

    A method of preparing improved technetium-99m labeled radiodiagnostic agents by reducing technetium-99m with stannous tartrate. Such radiodiagnostic agents are useful in scintigraphic examinations of the bone and lung. 31 claims, no drawings

  2. Extraction and identification of cyclobutanones from irradiated cheese employing a rapid direct solvent extraction method.

    Science.gov (United States)

    Tewfik, Ihab

    2008-01-01

    2-Alkylcyclobutanones (cyclobutanones) are accepted as chemical markers for irradiated foods containing lipid. However, current extraction procedures (Soxhlet-florisil chromatography) for the isolation of these markers involve a long and tedious clean-up regime prior to gas chromatography-mass spectrophotometry identification. This paper outlines an alternative isolation and clean-up method for the extraction of cyclobutanones in irradiated Camembert cheese. The newly developed direct solvent extraction method enables the efficient screening of large numbers of food samples and is not as resource intensive as the BS EN 1785:1997 method. Direct solvent extraction appears to be a simple, robust method and has the added advantage of a considerably shorter extraction time for the analysis of foods containing lipid.

  3. [Exploring a new method for superimposition of pre-treatment and post-treatment mandibular digital dental casts in adults].

    Science.gov (United States)

    Dai, F F; Liu, Y; Xu, T M; Chen, G

    2018-04-18

    To explore a cone beam computed tomography (CBCT)-independent method for mandibular digital dental cast superimposition to evaluate three-dimensional (3D) mandibular tooth movement after orthodontic treatment in adults, and to evaluate the accuracy of this method. Fifteen post-extraction orthodontic treatment adults from the Department of Orthodontics, Peking University School and Hospital of Stomatology were included. All the patients had four first premolars extracted, and were treated with straight wire appliance. The pre- and post-treatment plaster dental casts and craniofacial CBCT scans were obtained. The plaster dental casts were transferred to digital dental casts by 3D laser scanning, and lateral cephalograms were created from the craniofacial CBCT scans by orthogonal projection. The lateral cephalogram-based mandibular digital dental cast superimposition was achieved by sequential maxillary dental cast superimposition registered on the palatal stable region, occlusal transfer, and adjustment of mandibular rotation and translation obtained from lateral cephalogram superimposition. The accuracy of the lateral cephalogram-based mandibular digital dental cast superimposition method was evaluated with the CBCT-based mandibular digital dental cast superimposition method as the standard reference. After mandibular digital dental cast superimposition using both methods, 3D coordinate system was established, and 3D displacements of the lower bilateral first molars, canines and central incisors were measured. Differences between the two superimposition methods in tooth displacement measurements were assessed using the paired t-test with the level of statistical significance set at Pdigital dental cast superimposition methods in 3D displacements of the lower first molars, and sagittal and vertical displacements of the canines and central incisors; transverse displacements of the canines and central incisors differed by (0.3±0.5) mm with statistical significance

  4. ANALYSIS OF THE PIT REMOVAL METHODS IN DIGITAL TERRAIN MODELS OF VARIOUS RESOLUTIONS

    Directory of Open Access Journals (Sweden)

    S. Šamanović

    2016-06-01

    Full Text Available Digital terrain model (DTM is the base for calculation of the surface runoff under the influence of the gravity (gravity flow in hydrological analysis. It is important to produce hydrologically corrected DTM with the removed natural and artificial depressions to avoid numerical problems in algorithms of the gravity flow. The pit removal procedure changes geomorphometry of the DTM. GIS software packages use pit removal algorithm independently of geomorphmetric features of the analyzed area. In need of minimally modified DTM after the pit removal areas, the carving method (deepen drainage routes and the filling method (fill sink were analyzed on three different geomorphometric areas (bare mountain range, hilly wooded area and the plain area intersected with the network of the drainage canals. The recommendation is given for the choice of geomorphometric least changing DTM algorithm. The input data are raster data of elevation points created by stereoscopic photogrammetry method in 5x5 and 25x25 meter resolution. Differences have been noticed during the process of creating raster data. The recommendation is given for the choice of the most acceptable method for each type of area on the basis of comparison of the original elevation points with the elevation points in created DTM.

  5. Method of transmission of dynamic multibit digital images from micro-unmanned aerial vehicles

    Science.gov (United States)

    Petrov, E. P.; Kharina, N. L.

    2018-01-01

    In connection with successful usage of nanotechnologies in remote sensing great attention is paid to the systems in micro-unmanned aerial vehicles (MUAVs) capable to provide high spatial resolution of dynamic multibit digital images (MDI). Limited energy resources on board the MUAV do not allow transferring a large amount of video information in the shortest possible time. It keeps back the broad development of MUAV. The search for methods to shorten the transmission time of dynamic MDIs from MUAV over the radio channel leads to the methods of MDI compression without computational operations onboard the MUAV. The known compression codecs of video information can not be applied because of the limited energy resources. In this paper we propose a method for reducing the transmission time of dynamic MDIs without computational operations and distortions onboard the MUAV. To develop the method a mathematical apparatus of the theory of conditional Markov processes with discrete arguments was used. On its basis a mathematical model for the transformation of the MDI represented by binary images (BI) in the MDI, consisting of groups of neighboring BIs (GBI) transmitted by multiphase (MP) signals, is constructed. The algorithm for multidimensional nonlinear filtering of MP signals is synthesized, realizing the statistical redundancy of the MDI to compensate for the noise stability losses caused by the use of MP signals.

  6. Evaluation of extraction methods for ochratoxin A detection in cocoa beans employing HPLC.

    Science.gov (United States)

    Mishra, Rupesh K; Catanante, Gaëlle; Hayat, Akhtar; Marty, Jean-Louis

    2016-01-01

    Cocoa is an important ingredient for the chocolate industry and for many food products. However, it is prone to contamination by ochratoxin A (OTA), which is highly toxic and potentially carcinogenic to humans. In this work, four different extraction methods were tested and compared based on their recoveries. The best protocol was established which involves an organic solvent-free extraction method for the detection of OTA in cocoa beans using 1% sodium hydrogen carbonate (NaHCO3) in water within 30 min. The extraction method is rapid (as compared with existing methods), simple, reliable and practical to perform without complex experimental set-ups. The cocoa samples were freshly extracted and cleaned-up using immunoaffinity column (IAC) for HPLC analysis using a fluorescence detector. Under the optimised condition, the limit of detection (LOD) and limit of quantification (LOQ) for OTA were 0.62 and 1.25 ng ml(-1) respectively in standard solutions. The method could successfully quantify OTA in naturally contaminated samples. Moreover, good recoveries of OTA were obtained up to 86.5% in artificially spiked cocoa samples, with a maximum relative standard deviation (RSD) of 2.7%. The proposed extraction method could determine OTA at the level 1.5 µg kg(-)(1), which surpassed the standards set by the European Union for cocoa (2 µg kg(-1)). In addition, an efficiency comparison of IAC and molecular imprinted polymer (MIP) column was also performed and evaluated.

  7. Comparing a recursive digital filter with the moving-average and sequential probability-ratio detection methods for SNM portal monitors

    International Nuclear Information System (INIS)

    Fehlau, P.E.

    1993-01-01

    The author compared a recursive digital filter proposed as a detection method for French special nuclear material monitors with the author's detection methods, which employ a moving-average scaler or a sequential probability-ratio test. Each of these nine test subjects repeatedly carried a test source through a walk-through portal monitor that had the same nuisance-alarm rate with each method. He found that the average detection probability for the test source is also the same for each method. However, the recursive digital filter may have on drawback: its exponentially decreasing response to past radiation intensity prolongs the impact of any interference from radiation sources of radiation-producing machinery. He also examined the influence of each test subject on the monitor's operation by measuring individual attenuation factors for background and source radiation, then ranked the subjects' attenuation factors against their individual probabilities for detecting the test source. The one inconsistent ranking was probably caused by that subject's unusually long stride when passing through the portal

  8. Employing various metallography methods at high temperature alloy fatigue tests evaluation

    Directory of Open Access Journals (Sweden)

    Juraj Belan

    2016-12-01

    Full Text Available . Microstructures of superalloys have dramatically changed throughout the years, as modern technology of its casting or forging has become more sophisticated. The first superalloys have polyedric microstructure consisting of gamma solid solution, some fraction of gamma prime and of course grain boundaries. As demands on higher performance of aero jet engine increases, the changes in superalloys microstructure become more significant. A further step in microstructure evolution was directionally solidified alloys with columnar gamma prime particles. The latest microstructures are mostly monocrystalline, oriented in [001] direction of FCC gamma matrix. All microstructure changes bring necessity of proper preparation and evaluation of microstructure. Except for the already mentioned structures have gamma double prime and various carbides form can be seen. These structural parameters have mainly positive influence on important mechanical properties of superalloys. The paper deals with a microstructural evaluation of both groups of alloys – cast and as well as wrought. Microstructure evaluation helps to describe mechanism at various loading and failure of progressive superalloys. Such an example where microstructure evaluation is employed is fractography of failure surfaces after fatigue tests, which are examples of metallography evaluation described in this paper as a secondary objective.

  9. Method and apparatus for logging a borehole employing dual radiation detectors

    International Nuclear Information System (INIS)

    Arnold, D.M.

    1986-01-01

    An apparatus is described for logging a characteristic of a borehole in an earth formation employing nuclear count rate data selectively compensated for non-standard borehole conditions, comprising: a sonde, movable in a borehole, having: a radiation source for emitting radiation into earth formations adjacent the wellbore; first detector, spaced longitudinally from the radiation source, for detecting radiation scattered back to the detector and generating a first signal representative of a first count rate value, C/sub SS/; and second detector spaced a different longitudinal distance from the radiation source, for detecting radiation scattered back to the detector and generating a second signal representative of a count rate value, C/sub LS/; memory means for storing a predetermined threshold value, first predetermined relationships between the borehole characteristic and count rate values C/sub LS/, C/sub SS/; and second predetermined relationships between the borehole characteristic and ratios of C/sub LS/ to C/sub SS/; electronic means for producing a signal related in value to the borehole characteristic, which electronic means compares at least one of the first and second count rate value signals with the predetermined threshold value; means for recording the signal generated by the electronic means

  10. Changes in Ultrasonic Velocity from Fluid Substitution, Calculated with Laboratory Methods, Digital Rock Physics, and Biot Theory

    Science.gov (United States)

    Goldfarb, E. J.; Ikeda, K.; Tisato, N.

    2017-12-01

    Seismic and ultrasonic velocities of rocks are function of several variables including fluid saturation and type. Understanding the effect of each variable on elastic waves can be valuable when using seismic methods for subsurface modeling. Fluid type and saturation are of specific interest to volcanology, water, and hydrocarbon exploration. Laboratory testing is often employed to understand the effects of fluids on elastic waves. However, laboratory testing is expensive and time consuming. It normally requires cutting rare samples into regular shapes. Fluid injection can also destroy specimens as removing the fluid after testing can prove difficult. Another option is theoretical modeling, which can be used to predict the effect of fluids on elastic properties, but it is often inaccurate. Alternatively, digital rock physics (DRP) can be used to investigate the effect of fluid substitution. DRP has the benefit of being non invasive, as it does not require regular sample shapes or fluid injection. Here, we compare the three methods for dry and saturated Berea sandstone to test the reliability of DRP. First, ultrasonic velocities were obtained from laboratory testing. Second, for comparison, we used a purely theoretical approach - i.e., Hashin-Shtrikman and Biot theory - to estimate the wave speeds at dry and wet conditions. Third, we used DRP. The dry sample was scanned with micro Computed Tomography (µCT), and a three dimensional (3D) array was recorded. We employed a segmentation-less method to convert each 3D array value to density, porosity, elastic moduli, and wave speeds. Wave propagation was simulated numerically at similar frequency as the laboratory. To simulate fluid substitution, we numerically substituted air values for water and repeated the simulation. The results from DRP yielded similar velocities to the laboratory, and accurately predicted the velocity change from fluid substitution. Theoretical modeling could not accurately predict velocity, and

  11. How do Millennial Engineering and Technology Students Experience Learning Through Traditional Teaching Methods Employed in the University Setting?

    OpenAIRE

    Howard, Elizabeth A

    2011-01-01

    The purpose of the study was to document and analyze how Millennial engineering and technology students experience learning in large lecture classrooms. To help achieve this purpose, perceptions Millennials have toward traditional teaching methods employed in large lecture classes were analyzed and discussed. Additionally, this study documented how Millennials experienced technology within large lecture classrooms. A learning model depicting how Millennials experience learning within the larg...

  12. Comparison of digital radiography and apex locator with the conventional method in root length determination of primary teeth

    Directory of Open Access Journals (Sweden)

    I E Neena

    2011-01-01

    Full Text Available Aim: The purpose of this study was to compare the Working length in primary teeth endodontics using intra oral digital radiovisiography and apex locator with conventional method for accuracy. Materials and Methods: This in vivo study was conducted on 30 primary teeth which were indicated for pulpectomy in the patients of the age group of 5-11 years All experimental teeth had adequate remaining tooth structure for rubber dam isolation and radiographicaly visible canals. Endodontic treatment was required due to irreversible pulpitis or pulp necrosis. A standardized intraoral periapical radiograph of the tooth was taken using conventional method by paralleling technique. The distance between the source and the tooth, tooth and the films were standardized using X-ray positioning device. During the pulpectomy procedure, the working length was determined by digital radiograph and apex locator. The measurements were then compared with the conventional method of root canal measurement technique for accuracy Result: From the results obtained we can conclude that Working length determined in primary molars using digital radiography and Apex locator did not show any significant difference in the mean working length measurements when compared with the conventional radiographic method. Conclusions: Apex locator is comparable to conventional radiograph in determining the working length without radiation in the primary teeth. Intraoral digital radiography is the safest method in determining the working length with significant reduction in radiation exposure.Hence, both the techniques can be safely used as alternatives to conventional radiographic methods in determining working length in primary teeth.

  13. Accuracy and reliability of a novel method for fusion of digital dental casts and Cone Beam Computed Tomography scans.

    Directory of Open Access Journals (Sweden)

    Frits A Rangel

    Full Text Available Several methods have been proposed to integrate digital models into Cone Beam Computed Tomography scans. Since all these methods have some drawbacks such as radiation exposure, soft tissue deformation and time-consuming digital handling processes, we propose a new method to integrate digital dental casts into Cone Beam Computed Tomography scans. Plaster casts of 10 patients were randomly selected and 5 titanium markers were glued to the upper and lower plaster cast. The plaster models were scanned, impressions were taken from the plaster models and the impressions were also scanned. Linear measurements were performed on all three models, to assess accuracy and reproducibility. Besides that, matching of the scanned plaster models and scanned impressions was done, to assess the accuracy of the matching procedure. Results show that all measurement errors are smaller than 0.2 mm, and that 81% is smaller than 0.1 mm. Matching of the scanned plaster casts and scanned impressions show a mean error between the two surfaces of the upper arch of 0.14 mm and for the lower arch of 0.18 mm. The time needed for reconstructing the CBCT scans to a digital patient, where the impressions are integrated into the CBCT scan of the patient takes about 15 minutes, with little variance between patients. In conclusion, we can state that this new method is a reliable method to integrate digital dental casts into CBCT scans. As far as radiation exposure, soft tissue deformation and digital handling processes are concerned, it is a significant improvement compared to the previously published methods.

  14. Accuracy and Reliability of a Novel Method for Fusion of Digital Dental Casts and Cone Beam Computed Tomography Scans

    Science.gov (United States)

    Rangel, Frits A.; Maal, Thomas J. J.; Bronkhorst, Ewald M.; Breuning, K. Hero; Schols, Jan G. J. H.; Bergé, Stefaan J.; Kuijpers-Jagtman, Anne Marie

    2013-01-01

    Several methods have been proposed to integrate digital models into Cone Beam Computed Tomography scans. Since all these methods have some drawbacks such as radiation exposure, soft tissue deformation and time-consuming digital handling processes, we propose a new method to integrate digital dental casts into Cone Beam Computed Tomography scans. Plaster casts of 10 patients were randomly selected and 5 titanium markers were glued to the upper and lower plaster cast. The plaster models were scanned, impressions were taken from the plaster models and the impressions were also scanned. Linear measurements were performed on all three models, to assess accuracy and reproducibility. Besides that, matching of the scanned plaster models and scanned impressions was done, to assess the accuracy of the matching procedure. Results show that all measurement errors are smaller than 0.2 mm, and that 81% is smaller than 0.1 mm. Matching of the scanned plaster casts and scanned impressions show a mean error between the two surfaces of the upper arch of 0.14 mm and for the lower arch of 0.18 mm. The time needed for reconstructing the CBCT scans to a digital patient, where the impressions are integrated into the CBCT scan of the patient takes about 15 minutes, with little variance between patients. In conclusion, we can state that this new method is a reliable method to integrate digital dental casts into CBCT scans. As far as radiation exposure, soft tissue deformation and digital handling processes are concerned, it is a significant improvement compared to the previously published methods. PMID:23527111

  15. Exploration of operator method digital optical computers for application to NASA

    Science.gov (United States)

    1990-01-01

    Digital optical computer design has been focused primarily towards parallel (single point-to-point interconnection) implementation. This architecture is compared to currently developing VHSIC systems. Using demonstrated multichannel acousto-optic devices, a figure of merit can be formulated. The focus is on a figure of merit termed Gate Interconnect Bandwidth Product (GIBP). Conventional parallel optical digital computer architecture demonstrates only marginal competitiveness at best when compared to projected semiconductor implements. Global, analog global, quasi-digital, and full digital interconnects are briefly examined as alternative to parallel digital computer architecture. Digital optical computing is becoming a very tough competitor to semiconductor technology since it can support a very high degree of three dimensional interconnect density and high degrees of Fan-In without capacitive loading effects at very low power consumption levels.

  16. The Impact of Employer Attitude to Green Commuting Plans on Reducing Car Driving: A Mixed Method Analysis

    Directory of Open Access Journals (Sweden)

    Chuan Ding

    2014-04-01

    Full Text Available Reducing car trips and promoting green commuting modes are generally considered important solutions to reduce the increase of energy consumption and transportation CO2 emissions. One potential solution for alleviating transportation CO2 emissions has been to identify a role for the employer through green commuter programs. This paper offers an approach to assess the effects of employer attitudes towards green commuting plans on commuter mode choice and the intermediary role car ownership plays in the mode choice decision process. A mixed method which extends the traditional discrete choice model by incorporating latent variables and mediating variables with a structure equation model was used to better understand the commuter mode choice behaviour. The empirical data were selected from Washington-Baltimore Regional Household Travel Survey in 2007-2008, including all the trips from home to workplace during the morning hours. The model parameters were estimated using the simultaneous estimation approach and the integrated model turns out to be superior to the traditional multinomial logit (MNL model accounting for the impact of employer attitudes towards green commuting. The direct and indirect effects of socio-demographic attributes and employer attitudes towards green commuting were estimated. Through the structural equation modelling with mediating variable, this approach confirmed the intermediary nature of car ownership in the choice process. The results found in this paper provide helpful information for transportation and planning policymakers to test the transportation and planning policies effects and encourage green commuting reducing transportation CO2 emissions.

  17. Defining Instructional Quality by Employing the Total Quality Management (TQM) Method: A Research Project.

    Science.gov (United States)

    Croker, Robert E.; And Others

    The feasibility of using W. E. Deming's total quality management (TQM) method to define instructional quality was examined by surveying three groups of students attending Idaho State University's College of Education and School of Applied Technology: 31 students seeking cosmetology certification; 75 undergraduates pursuing degrees in corporate…

  18. 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.

  19. The effect of loading methods and parameters on defect detection in digital shearography

    Science.gov (United States)

    Yang, Fu; Ye, Xingchen; Qiu, Zisheng; Zhang, Borui; Zhong, Ping; Liang, ZhiYong; Sun, Zeyu; Zhu, Shu

    Digital Shearography Speckle Pattern Interferometry (DSSPI) is a non-destructive testing technique, which has a wide range of applications in industrial field due to the merits of non-contact, fast response, full-field measurement and high sensitivity. However, in the real application, the loading methods and parameters usually depend on the experience of the operator, which affect the effectiveness and accuracy of the test. Based on this background and the principle of DSSPI, a model using finite element analysis software and Matlab is established to simulate the defects detections of aluminum plate and composite laminates under different loading conditions. The simulation covers loading methods, shearing direction, shearing amount, loading intensity, defect size, defect depth and defect position. In order to quantify the testing effect, a parameter named the deviation D is first defined. And through the parameter D, the simulation system can evaluate the system detection ability. The work in this paper can provide systematic guidance for the choice of loading methods and parameters in the real DSSPI experiment system.

  20. Comparison of digital methods for storage, sorting and displaying of the spectrometric information

    International Nuclear Information System (INIS)

    Dryapachenko, I.P.; Mozhzhukhin, E.M.; Ostashko, V.V.; And Others

    2012-01-01

    During ten years at the Kyiv tandem EGP-10K beam of accelerated hydrogen ions was used extensively in the inclusive and exclusive experiments with scattering and nuclear reactions on different nuclei. Charged particles (protons, deuterons, 4 He),γ-quanta and neutrons were registered in the outgoing channels of the studied nuclear processes. This required to use of different methods of radiation spectrometry. The most used (δE x E)-method for spectrometry of charged particles and the time-of-flight method for registration and the separation of neutrons and ?-rays. The current need of the algorithm universalization for measurement and data processing was led to the development, installation and use of computerized multiparameter setup that was used successfully in this time in the beam experiments. This paper discusses the results of the facility modernization in accordance with the development of digital technology, above all, communication devices for measuring apparatus and control computer, and related changes and improves of the operating systems and software for data processing

  1. Development and experience of quality control methods for digital breast tomosynthesis systems.

    Science.gov (United States)

    Strudley, Cecilia J; Young, Kenneth C; Looney, Padraig; Gilbert, Fiona J

    2015-01-01

    To develop tomosynthesis quality control (QC) test methods and use them alongside established two-dimensional (2D) QC tests to measure the performance of digital breast tomosynthesis (DBT) systems used in a comparative trial with 2D mammography. DBT QC protocols and associated analysis were developed, incorporating adaptions of some 2D tests as well as some novel tests. The tomosynthesis tests were: mean glandular dose to the standard breast model; contrast-to-noise ratio in reconstructed focal planes; geometric distortion; artefact spread; threshold contrast detail detection in reconstructed focal planes, alignment of the X-ray beam to the reconstructed image and missed tissue; reproducibility of the tomosynthesis exposure; and homogeneity of the reconstructed focal planes. Summaries of results from the tomosynthesis QC tests are presented together with some 2D results for comparison. The tomosynthesis QC tests and analysis methods developed were successfully applied. The lessons learnt, which are detailed in the Discussion section, may be helpful to others embarking on DBT QC programmes. DBT performance test equipment and analysis methods have been developed. The experience gained has contributed to the subsequent drafting of DBT QC protocols in the UK and Europe.

  2. Multi-energy method of digital radiography for imaging of biological objects

    Science.gov (United States)

    Ryzhikov, V. D.; Naydenov, S. V.; Opolonin, O. D.; Volkov, V. G.; Smith, C. F.

    2016-03-01

    This work has been dedicated to the search for a new possibility to use multi-energy digital radiography (MER) for medical applications. Our work has included both theoretical and experimental investigations of 2-energy (2E) and 3- energy (3D) radiography for imaging the structure of biological objects. Using special simulation methods and digital analysis based on the X-ray interaction energy dependence for each element of importance to medical applications in the X-ray range of energy up to 150 keV, we have implemented a quasi-linear approximation for the energy dependence of the X-ray linear mass absorption coefficient μm (E) that permits us to determine the intrinsic structure of the biological objects. Our measurements utilize multiple X-ray tube voltages (50, 100, and 150 kV) with Al and Cu filters of different thicknesses to achieve 3-energy X-ray examination of objects. By doing so, we are able to achieve significantly improved imaging quality of the structure of the subject biological objects. To reconstruct and visualize the final images, we use both two-dimensional (2D) and three-dimensional (3D) palettes of identification. The result is a 2E and/or 3E representation of the object with color coding of each pixel according to the data outputs. Following the experimental measurements and post-processing, we produce a 3D image of the biological object - in the case of our trials, fragments or parts of chicken and turkey.

  3. The use of digital PCR to improve the application of quantitative molecular diagnostic methods for tuberculosis.

    Science.gov (United States)

    Devonshire, Alison S; O'Sullivan, Denise M; Honeyborne, Isobella; Jones, Gerwyn; Karczmarczyk, Maria; Pavšič, Jernej; Gutteridge, Alice; Milavec, Mojca; Mendoza, Pablo; Schimmel, Heinz; Van Heuverswyn, Fran; Gorton, Rebecca; Cirillo, Daniela Maria; Borroni, Emanuele; Harris, Kathryn; Barnard, Marinus; Heydenrych, Anthenette; Ndusilo, Norah; Wallis, Carole L; Pillay, Keshree; Barry, Thomas; Reddington, Kate; Richter, Elvira; Mozioğlu, Erkan; Akyürek, Sema; Yalçınkaya, Burhanettin; Akgoz, Muslum; Žel, Jana; Foy, Carole A; McHugh, Timothy D; Huggett, Jim F

    2016-08-03

    Real-time PCR (qPCR) based methods, such as the Xpert MTB/RIF, are increasingly being used to diagnose tuberculosis (TB). While qualitative methods are adequate for diagnosis, the therapeutic monitoring of TB patients requires quantitative methods currently performed using smear microscopy. The potential use of quantitative molecular measurements for therapeutic monitoring has been investigated but findings have been variable and inconclusive. The lack of an adequate reference method and reference materials is a barrier to understanding the source of such disagreement. Digital PCR (dPCR) offers the potential for an accurate method for quantification of specific DNA sequences in reference materials which can be used to evaluate quantitative molecular methods for TB treatment monitoring. To assess a novel approach for the development of quality assurance materials we used dPCR to quantify specific DNA sequences in a range of prototype reference materials and evaluated accuracy between different laboratories and instruments. The materials were then also used to evaluate the quantitative performance of qPCR and Xpert MTB/RIF in eight clinical testing laboratories. dPCR was found to provide results in good agreement with the other methods tested and to be highly reproducible between laboratories without calibration even when using different instruments. When the reference materials were analysed with qPCR and Xpert MTB/RIF by clinical laboratories, all laboratories were able to correctly rank the reference materials according to concentration, however there was a marked difference in the measured magnitude. TB is a disease where the quantification of the pathogen could lead to better patient management and qPCR methods offer the potential to rapidly perform such analysis. However, our findings suggest that when precisely characterised materials are used to evaluate qPCR methods, the measurement result variation is too high to determine whether molecular quantification

  4. 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...

  5. Evaluating unsupervised methods to size and classify suspended particles using digital in-line holography

    Science.gov (United States)

    Davies, Emlyn J.; Buscombe, Daniel D.; Graham, George W.; Nimmo-Smith, W. Alex M.

    2015-01-01

    Substantial information can be gained from digital in-line holography of marine particles, eliminating depth-of-field and focusing errors associated with standard lens-based imaging methods. However, for the technique to reach its full potential in oceanographic research, fully unsupervised (automated) methods are required for focusing, segmentation, sizing and classification of particles. These computational challenges are the subject of this paper, in which we draw upon data collected using a variety of holographic systems developed at Plymouth University, UK, from a significant range of particle types, sizes and shapes. A new method for noise reduction in reconstructed planes is found to be successful in aiding particle segmentation and sizing. The performance of an automated routine for deriving particle characteristics (and subsequent size distributions) is evaluated against equivalent size metrics obtained by a trained operative measuring grain axes on screen. The unsupervised method is found to be reliable, despite some errors resulting from over-segmentation of particles. A simple unsupervised particle classification system is developed, and is capable of successfully differentiating sand grains, bubbles and diatoms from within the surf-zone. Avoiding miscounting bubbles and biological particles as sand grains enables more accurate estimates of sand concentrations, and is especially important in deployments of particle monitoring instrumentation in aerated water. Perhaps the greatest potential for further development in the computational aspects of particle holography is in the area of unsupervised particle classification. The simple method proposed here provides a foundation upon which further development could lead to reliable identification of more complex particle populations, such as those containing phytoplankton, zooplankton, flocculated cohesive sediments and oil droplets.

  6. Employment of a novel ultrasonic method to investigate high pressure phase transitions in oleic acid

    Science.gov (United States)

    Rostocki, A. J.; Siegoczyński, R. M.; Kiełczyński, P.; Szalewski, M.; Balcerzak, A.; Zduniak, M.

    2011-06-01

    In this work, the variation of sound velocity with hydrostatic pressure for oleic acid is evaluated up to 350 MPa. During the measurement, we identified the phase transformation of oleic acid and the presence of the hysteresis of the dependence of sound velocity on pressure. From the performed measurements, it can be seen that the dependence of sound velocity on pressure can be used to investigate phase transformations in natural oils. Ultrasonic waves were excited and detected using piezoelectric LiNbO3(Y-36 cut) 5 MHz transducers. The phase velocity of the longitudinal ultrasonic waves was measured using a cross-correlation method to evaluate the time of flight.

  7. Bioengineering methods employed in the study of wound healing of sulphur mustard burns.

    Science.gov (United States)

    Graham, John S; Schomacker, Kevin T; Glatter, Robert D; Briscoe, Crystal M; Braue, Ernest H; Squibb, Katherine S

    2002-02-01

    Sulphur mustard (SM) is a potent incapacitating chemical warfare agent that remains a threat to war fighters and civilians worldwide. SM lesions may require weeks or months to heal, depending upon their severity. This study was undertaken to find a treatment regimen that promotes speedier healing of deep cutaneous SM burns in a weanling pig model. The principal objective of the study was to compare four treatment regimens and establish which achieved the shortest healing time. Twelve Yorkshire Cross weanling pigs were exposed to SM liquid for 2h, generating six large deep dermal/full thickness burns on the ventrum of each animal. Three additional animals served as sham-exposed controls. Surgical intervention occurred at 48 h postexposure. Treatments included: (i) full-thickness debridement of the burns with a computer controlled, raster scanned continuous wave CO2 laser followed by autologous split-thickness skin grafting; (ii) full-thickness sharp surgical tangential excision followed by skin grafting, the 'Gold Standard' used in human deep dermal/full-thickness thermal burns management; (iii) partial-thickness laser ablation with no grafting; and (iv) partial-thickness sharp surgical excision with no grafting. Several non-invasive bioengineering methods were used to monitor the progress of wound healing throughout a 36-day healing period: reflectance colourimetry, evaporimetry, laser Doppler perfusion imaging and ballistometry. Bioengineering methods indicated that laser debridement followed by autologous split-thickness skin grafting was as efficacious in improving the wound healing of deep SM burns in weanling swine as the 'Gold Standard.' Regardless of the method of debridement, barrier function, skin colour and mechanical properties returned to near-normal levels within 15 days of treatment in the grafted sites. Regardless of surgical approach, blood flux levels remained approximately 50-60% of normal tissue throughout the 36-day postsurgical observation

  8. Targeted Query Expansions as a Method for Searching Mixed Quality Digitized Cultural Heritage Documents

    NARCIS (Netherlands)

    Keskustalo, H.; Kettunen, K.; Kumpulainen, S.; Ferro, N.; Silvello, G.; Järvelin, A.; Kekäläinen, J.; Arvola, P.; Saastamoinen, M.; Sormunen, E.; Järvelin, K.

    2015-01-01

    Digitization of cultural heritage is a huge ongoing effort in many countries. In digitized historical documents, words may occur in different surface forms due to three types of variation - morphological variation, historical variation, and errors in optical character recognition (OCR). Because

  9. Cases on Digital Game-Based Learning: Methods, Models, and Strategies

    Science.gov (United States)

    Baek, Youngkyun; Whitton, Nicola

    2013-01-01

    In K-12 classrooms, as well as on the college and university level, the incorporation of digital games has played a vital role in the educational system. While introducing teachers to new fields, these digital games have been designed and implemented for the classroom and have shown positive results at a variety of educational levels. Cases on…

  10. Segmentation methods for breast vasculature in dual-energy contrast-enhanced digital breast tomosynthesis

    Science.gov (United States)

    Lau, Kristen C.; Lee, Hyo Min; Singh, Tanushriya; Maidment, Andrew D. A.

    2015-03-01

    Dual-energy contrast-enhanced digital breast tomosynthesis (DE CE-DBT) uses an iodinated contrast agent to image the three-dimensional breast vasculature. The University of Pennsylvania has an ongoing DE CE-DBT clinical study in patients with known breast cancers. The breast is compressed continuously and imaged at four time points (1 pre-contrast; 3 post-contrast). DE images are obtained by a weighted logarithmic subtraction of the high-energy (HE) and low-energy (LE) image pairs. Temporal subtraction of the post-contrast DE images from the pre-contrast DE image is performed to analyze iodine uptake. Our previous work investigated image registration methods to correct for patient motion, enhancing the evaluation of vascular kinetics. In this project we investigate a segmentation algorithm which identifies blood vessels in the breast from our temporal DE subtraction images. Anisotropic diffusion filtering, Gabor filtering, and morphological filtering are used for the enhancement of vessel features. Vessel labeling methods are then used to distinguish vessel and background features successfully. Statistical and clinical evaluations of segmentation accuracy in DE-CBT images are ongoing.

  11. [Digitalization of histological images as a method of quantifying the demyelinating process].

    Science.gov (United States)

    Stojiljković, G; Tasić, M; Budakov, B

    1996-01-01

    The basic aim of this paper was to check the hypothesis whether after head trauma the brain tissue looses myelinic membrane which surrounds the axon, and if this possibly established loss can be quantified, that is if it is possible to determine the degree of disintegration. One of the aims was to examine this method itself. The gathered results show that both the hypothesis and the aims were justified. It has been established that the diffuse axonal lesion in the examined samples reflects in a loss of axon's myelinic membrane. The loss was 50% greater in the test group in regard to the control group. To digitalize histologic pictures we have used Laser Scanner Densitometry Station and software by Biomed. In regard to medical jurisprudence, the laser scanner densitometry offers more relevant data in cases apparently unclear and in sudden deaths after head injuries. Application of this method and further investigations will be directed to further attempts to clear up connections between the mechanism of injury and degree of biologic response of the brain tissue.

  12. Comparison of beam position calculation methods for application in digital acquisition systems

    Science.gov (United States)

    Reiter, A.; Singh, R.

    2018-05-01

    Different approaches to the data analysis of beam position monitors in hadron accelerators are compared adopting the perspective of an analog-to-digital converter in a sampling acquisition system. Special emphasis is given to position uncertainty and robustness against bias and interference that may be encountered in an accelerator environment. In a time-domain analysis of data in the presence of statistical noise, the position calculation based on the difference-over-sum method with algorithms like signal integral or power can be interpreted as a least-squares analysis of a corresponding fit function. This link to the least-squares method is exploited in the evaluation of analysis properties and in the calculation of position uncertainty. In an analytical model and experimental evaluations the positions derived from a straight line fit or equivalently the standard deviation are found to be the most robust and to offer the least variance. The measured position uncertainty is consistent with the model prediction in our experiment, and the results of tune measurements improve significantly.

  13. Methods for accurate cold-chain temperature monitoring using digital data-logger thermometers

    Science.gov (United States)

    Chojnacky, M. J.; Miller, W. M.; Strouse, G. F.

    2013-09-01

    Complete and accurate records of vaccine temperature history are vital to preserving drug potency and patient safety. However, previously published vaccine storage and handling guidelines have failed to indicate a need for continuous temperature monitoring in vaccine storage refrigerators. We evaluated the performance of seven digital data logger models as candidates for continuous temperature monitoring of refrigerated vaccines, based on the following criteria: out-of-box performance and compliance with manufacturer accuracy specifications over the range of use; measurement stability over extended, continuous use; proper setup in a vaccine storage refrigerator so that measurements reflect liquid vaccine temperatures; and practical methods for end-user validation and establishing metrological traceability. Data loggers were tested using ice melting point checks and by comparison to calibrated thermocouples to characterize performance over 0 °C to 10 °C. We also monitored logger performance in a study designed to replicate the range of vaccine storage and environmental conditions encountered at provider offices. Based on the results of this study, the Centers for Disease Control released new guidelines on proper methods for storage, handling, and temperature monitoring of vaccines for participants in its federally-funded Vaccines for Children Program. Improved temperature monitoring practices will ultimately decrease waste from damaged vaccines, improve consumer confidence, and increase effective inoculation rates.

  14. Residual stress measurement of PMMA by combining drilling-hole with digital speckle correlation method

    Science.gov (United States)

    Yao, X. F.; Xiong, T. C.; Xu, H. M.; Wan, J. P.; Long, G. R.

    2008-11-01

    The residual stresses of the PMMA (polymethyl methacrylate) specimens after being drilled, reamed and polished respectively are investigated using the digital speckle correlation experimental method,. According to the displacement fields around the correlated calculated region, the polynomial curve fitting method is used to obtain the continuous displacement fields, and the strain fields can be obtained from the derivative of the displacement fields. Considering the constitutive equation of the material, the expression of the residual stress can be presented. During the data processing, according to the fitting effect of the data, the calculation region of the correlated speckles and the degree of the polynomial fitting curve is decided. These results show that the maximum stress is at the hole-wall of the drilling hole specimen and with the increasing of the diameter of the drilled hole, the residual stress resulting from the hole drilling increases, whereas the process of reaming and polishing hole can reduce the residual stress. The relative large discrete degree of the residual stress is due to the chip removal ability of the drill bit, the cutting feed of the drill and other various reasons.

  15. A study of digital hardware architectures for nuclear reactors protection systems applications - reliability and safety analysis methods; Um estudo de arquiteturas de hardware para aplicacao em sistemas digitais de protecao de reatores nucleares - metodos de analise de confiabilidade e seguranca

    Energy Technology Data Exchange (ETDEWEB)

    Benko, Pedro Luiz

    1997-07-01

    A study of digital hardware architectures, including experience in many countries, topologies and solutions to interface circuits for protection systems of nuclear reactors is presented. Methods for developing digital systems architectures based on fault tolerant and safety requirements is proposed. Directives for assessing such conditions are suggested. Techniques and the most common tools employed in reliability, safety evaluation and modeling of hardware architectures is also presented. Markov chain modeling is used to evaluate the reliability of redundant architectures. In order to estimate software quality, several mechanisms to be used in design, specification, and validation and verification (V and V) procedures are suggested. A digital protection system architecture has been analyzed as a case study. (author)

  16. Method of purifying metallurgical grade silicon employing reduced pressure atmospheric control

    Science.gov (United States)

    Ingle, W. M.; Thompson, S. W.; Chaney, R. E. (Inventor)

    1979-01-01

    A method in which a quartz tube is charged with chunks of metallurgical grade silicon and/or a mixture of such chunks and high purity quartz sand, and impurities from a class including aluminum, boron, as well as certain transition metals including nickel, iron, and manganese is described. The tube is then evacuated and heated to a temperature within a range of 800 C to 1400 C. A stream of gas comprising a reactant, such as silicon tetrafluoride, is continuously delivered at low pressures through the charge for causing a metathetical reaction of impurities of the silicon and the reactant to occur for forming a volatile halide and leaving a residue of silicon of an improved purity. The reactant which included carbon monoxide gas and impurities such as iron and nickel react to form volatile carbonyls.

  17. Development of a method employing chitosan to remove metallic ions from wastewater

    International Nuclear Information System (INIS)

    Janegitz, Bruno Campos; Lourencao, Bruna Claudia; Lupetti, Karina Omuro; Fatibello-Filho, Orlando

    2007-01-01

    In this work a method was developed for removing metallic ions from wastewaters by co-precipitation of Cu 2+ , Pb 2+ , Cd 2+ , Cr 3+ and Hg 2+ with chitosan and sodium hydroxide solution. Solutions of these metallic ions in the range from 0.55 to 2160 mg L -1 were added to chitosan dissolved in 0.05 mol L -1 HCl. For the co-precipitation of metal-chitosan-hydroxide a 0.17 mol L -1 NaOH solution was added until pH 8.5-9.5. A parallel study was carried out applying a 0.17 mol L -1 NaOH solution to precipitate those metallic ions. Also, a chitosan solid phase column was used for removing those metallic ions from wastewaters. (author)

  18. Method for simultaneous measurement of borehole and formation neutron decay-times employing iterative fitting

    International Nuclear Information System (INIS)

    Schultz, W.E.

    1982-01-01

    A method is described of making in situ measurements of the thermal neutron decay time of earth formations in the vicinity of a wellbore. The borehole and earth formations in its vicinity are repetitively irradiated with pulsed fast neutrons and, during the intervals between pulses, capture gamma radiation is measured in at least four, non-overlapping, contiguous time intervals. A background radiation measurement is made between successive pulses and used to correct count-rates representative of thermal neutron populations in the borehole and the formations, the count-rates being generated during each of the time intervals. The background-corrected count-rate measurements are iteratively fitted to exponential curves using a least squares technique to simultaneously derive signals representing borehole component and formation component of the thermal neutron decay time. The signals are recorded as a function of borehole depth. (author)

  19. Leveraging social and digital media for participant recruitment: A review of methods from the Bayley Short Form Formative Study

    OpenAIRE

    Burke-Garcia, Amelia; Mathew, Sunitha

    2017-01-01

    Introduction Social media is increasingly being used in research, including recruitment. Methods For the Bayley Short Form Formative Study, which was conducted under the the National Children’s Study, traditional methods of recruitment proved to be ineffective. Therefore, digital media were identified as potential channels for recruitment. Results Results included successful recruitment of over 1800 infant and toddler participants to the Study. Conclusions This paper outlines the methods, res...

  20. A review of output-only structural mode identification literature employing blind source separation methods

    Science.gov (United States)

    Sadhu, A.; Narasimhan, S.; Antoni, J.

    2017-09-01

    Output-only modal identification has seen significant activity in recent years, especially in large-scale structures where controlled input force generation is often difficult to achieve. This has led to the development of new system identification methods which do not require controlled input. They often work satisfactorily if they satisfy some general assumptions - not overly restrictive - regarding the stochasticity of the input. Hundreds of papers covering a wide range of applications appear every year related to the extraction of modal properties from output measurement data in more than two dozen mechanical, aerospace and civil engineering journals. In little more than a decade, concepts of blind source separation (BSS) from the field of acoustic signal processing have been adopted by several researchers and shown that they can be attractive tools to undertake output-only modal identification. Originally intended to separate distinct audio sources from a mixture of recordings, mathematical equivalence to problems in linear structural dynamics have since been firmly established. This has enabled many of the developments in the field of BSS to be modified and applied to output-only modal identification problems. This paper reviews over hundred articles related to the application of BSS and their variants to output-only modal identification. The main contribution of the paper is to present a literature review of the papers which have appeared on the subject. While a brief treatment of the basic ideas are presented where relevant, a comprehensive and critical explanation of their contents is not attempted. Specific issues related to output-only modal identification and the relative advantages and limitations of BSS methods both from theoretical and application standpoints are discussed. Gap areas requiring additional work are also summarized and the paper concludes with possible future trends in this area.

  1. Review of research designs and statistical methods employed in dental postgraduate dissertations.

    Science.gov (United States)

    Shirahatti, Ravi V; Hegde-Shetiya, Sahana

    2015-01-01

    There is a need to evaluate the quality of postgraduate dissertations of dentistry submitted to university in the light of the international standards of reporting. We conducted the review with an objective to document the use of sampling methods, measurement standardization, blinding, methods to eliminate bias, appropriate use of statistical tests, appropriate use of data presentation in postgraduate dental research and suggest and recommend modifications. The public access database of the dissertations from Rajiv Gandhi University of Health Sciences was reviewed. Three hundred and thirty-three eligible dissertations underwent preliminary evaluation followed by detailed evaluation of 10% of randomly selected dissertations. The dissertations were assessed based on international reporting guidelines such as strengthening the reporting of observational studies in epidemiology (STROBE), consolidated standards of reporting trials (CONSORT), and other scholarly resources. The data were compiled using MS Excel and SPSS 10.0. Numbers and percentages were used for describing the data. The "in vitro" studies were the most common type of research (39%), followed by observational (32%) and experimental studies (29%). The disciplines conservative dentistry (92%) and prosthodontics (75%) reported high numbers of in vitro research. Disciplines oral surgery (80%) and periodontics (67%) had conducted experimental studies as a major share of their research. Lacunae in the studies included observational studies not following random sampling (70%), experimental studies not following random allocation (75%), not mentioning about blinding, confounding variables and calibrations in measurements, misrepresenting the data by inappropriate data presentation, errors in reporting probability values and not reporting confidence intervals. Few studies showed grossly inappropriate choice of statistical tests and many studies needed additional tests. Overall observations indicated the need to

  2. Migration experiences, employment status and psychological distress among Somali immigrants: a mixed-method international study

    Directory of Open Access Journals (Sweden)

    Warfa Nasir

    2012-09-01

    Full Text Available Abstract Background The discourse about mental health problems among migrants and refugees tends to focus on adverse pre-migration experiences; there is less investigation of the environmental conditions in which refugee migrants live, and the contrasts between these situations in different countries. This cross-national study of two samples of Somali refugees living in London (UK and Minneapolis, Minnesota, (USA helps to fill a gap in the literature, and is unusual in being able to compare information collected in the same way in two cities in different countries. Methods There were two parts to the study, focus groups to gather in-depth qualitative data and a survey of health status and quantifiable demographic and material factors. Three of the focus groups involved nineteen Somali professionals and five groups included twenty-eight lay Somalis who were living in London and Minneapolis. The quantitative survey was done with 189 Somali respondents, also living in London and Minneapolis. We used the MINI International Neuropsychiatric Interview (MINI to assess ICD-10 and DSM-IV mental disorders. Results The overall qualitative and quantitative results suggested that challenges to masculinity, thwarted aspirations, devalued refugee identity, unemployment, legal uncertainties and longer duration of stay in the host country account for poor psychological well-being and psychiatric disorders among this group. Conclusion The use of a mixed-methods approach in this international study was essential since the quantitative and qualitative data provide different layers and depth of meaning and complement each other to provide a fuller picture of complex and multi-faceted life situations of refugees and asylum seekers. The comparison between the UK and US suggests that greater flexibility of access to labour markets for this refugee group might help to promote opportunities for better integration and mental well-being.

  3. Comparisons between digital gamma-ray spectrometer (DSPec) and standard nuclear instrumentation methods (NIM) systems

    International Nuclear Information System (INIS)

    Vo, D.T.; Russo, P.A.; Sampson, T.E.

    1998-03-01

    Safeguards isotopic measurements require the best spectrometer systems with excellent resolution, stability and throughput. Up until about a year ago, gamma ray spectroscopy has always been done using the analog amplifier, which processes the pulses from the preamplifier to remove the noise, reject the pile up signals, and shape the signals into some desirable form before sending them to the analog to digital converter (ADC) to be digitized. In late 1996, EG and G Ortec introduced a digital gamma ray spectrometer (DSPec) which uses digital technology to analyze the preamplifiers' pulses from all types of germanium and silicon detectors. Considering its performance, digital based spectroscopy may become the way of future gamma ray spectroscopy

  4. Method and apparatus for digitally based high speed x-ray spectrometer

    International Nuclear Information System (INIS)

    Warburton, W.K.; Hubbard, B.

    1997-01-01

    A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a ''hardwired'' processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer. 19 figs

  5. An evaluation method of fault-tolerance for digital plant protection system in nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Jun Seok; Kim, Man Cheol; Seong, Poong Hyun; Kang, Hyun Gook; Jang, Seung Cheol

    2005-01-01

    In recent years, analog based nuclear power plant (NPP) safety related instrumentation and control (I and C) systems have been replaced to modern digital based I and C systems. NPP safety related I and C systems require very high design reliability compare to the conventional digital systems so that reliability assessment is very important. In the reliability assessment of the digital system, fault tolerance evaluation is one of the crucial factors. However, the evaluation is very difficult because the digital system in NPP is very complex. In this paper, the simulation based fault injection technique on simplified processor is used to evaluate the fault-tolerance of the digital plant protection system (DPPS) with high efficiency with low cost

  6. Explanation of the methods employed in the statistical evaluation of SALE program data

    International Nuclear Information System (INIS)

    Bracey, J.T.; Soriano, M.

    1981-01-01

    The analysis of Safeguards Analytical Laboratory Evaluation (SALE) bimonthly data is described. Statistical procedures are discussed in Section A, followed by the descriptions of tabular and graphic values in Section B. Calculation formulae for the various statistics in the reports are presented in Section C. SALE data reported to New Brunswick Laboratory (NBL) are entered into a computerized system through routine data processing procedures. Bimonthly and annual reports are generated from this data system. In the bimonthly data analysis, data from the six most recent reporting periods of each laboratory-material-analytical method combination are utilized. Analysis results in the bimonthly reports are only presented for those participants who have reported data at least once during the last 12-month period. Reported values are transformed to relative percent difference values calculated by [(reported value - reference value)/reference value] x 100. Analysis of data is performed on these transformed values. Accordingly, the results given in the bimonthly report are (relative) percent differences (% DIFF). Suspect, large variations are verified with individual participants to eliminate errors in the transcription process. Statistical extreme values are not excluded from bimonthly analysis; all data are used

  7. Nucleic acid hybridization assays employing dA-tailed capture probes. II. Advanced multiple capture methods

    International Nuclear Information System (INIS)

    Hunsaker, W.R.; Badri, H.; Lombardo, M.; Collins, M.L.

    1989-01-01

    A fourth capture is added to the reversible target capture procedure. This results in an improved radioisotopic detection limit of 7.3 x 10(-21) mol of target. In addition, the standard triple capture method is converted into a nonradioactive format with a detection limit of under 1 amol of target. The principal advantage of nonradioactive detection is that the entire assay can be performed in about 1 h. Nucleic acids are released from cells in the presence of the (capture probe) which contains a 3'-poly(dA) sequence and the (labeled probe) which contains a detectable nonradioactive moiety such as biotin. After a brief hybridization in solution, the target is captured on oligo(dT) magnetic particles. The target is further purified from sample impurities and excess labeled probe by recapture either once or twice more on fresh magnetic particles. The highly purified target is then concentrated to 200 nl by recapture onto a poly(dT) nitrocellulose filter and rapidly detected with streptavidin-alkaline phosphatase using bromochloroindolyl phosphate and nitroblue tetrazolium. Using this procedure, as little as 0.25 amol of a target plasmid has been detected nonradioactively in crude samples in just 1 h without prior purification of the DNA and RNA. Finally, a new procedure called background capture is introduced to complement the background-reducing power of RTC

  8. Triacylglycerol secretion in rats: validation of a tracer method employing radioactive glycerol

    International Nuclear Information System (INIS)

    Bird, M.; Williams, M.A.; Baker, N.

    1984-01-01

    A two-compartment model was developed to analyze the temporal changes in plasma triacylglycerol (TG)-specific radioactivity after injection of [2- 3 H]glycerol into rats. The analysis, which yielded fractional rate constants of TG secretion, was tested in rats fed diets either adequate or deficient in essential fatty acids (EFA) and containing either glucose, fructose or sucrose as the dietary carbohydrate. The method of analysis appeared valid, first, because of a close agreement between experimental and computer-fitted TG-specific radioactivity curves, and second, because the fractional rate constants obtained were quite similar to fractional rate constants determined previously by the Triton WR-1339 technique in rats maintained on identical diets. The results show that EFA deficiency increased the fractional rate constant of TG secretion 1.7-, 1.8- and 3.3-fold and the rate of TG secretion 1.8-, 1.6- and 1.4-fold when the dietary carbohydrate was glucose, sucrose and fructose, respectively, in comparison with control rats fed diets supplying these same carbohydrates but adequate in EFA. In the latter groups, the rates of plasma TG secretion were in the range of 0.14-0.17 mg/min per 100 g body weight, and the rate of secretion in the fructose-fed rats was only 20% higher than in the glucose-fed rats

  9. Full 3D internal strain measurement for device packaging materials using synchrotron laminography and volumetric digital image correlation method

    International Nuclear Information System (INIS)

    Asada, Takashi; Kimura, Hidehiko; Yamaguchi, Satoshi; Kano, Taiki; Kajiwara, Kentaro

    2014-01-01

    In order to measure full 3D internal strain field of resin molding compound specimens, synchrotron computed tomography and laminography at SPring-8 were performed. Then the reconstructed images were applied to 3D digital image correlation method to compute internal strain field. The results showed that internal strains in resin molding compound could be visualized in this way. (author)

  10. An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems.

    NARCIS (Netherlands)

    Bouwman, R.; Young, K.; Lazzari, B.; Ravaglia, V.; Broeders, M.J.M.; Engen, R. van

    2009-01-01

    According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does

  11. Light-reflection random-target method for measurement of the modulation transfer function of a digital video-camera

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Jaroslav; Jakubík, P.; Machala, L.

    2005-01-01

    Roč. 116, - (2005), s. 573-585 ISSN 0030-4026 Institutional research plan: CEZ:AV0Z10100522 Keywords : random-target measuring method * light-reflection white - noise target * digital video camera * modulation transfer function * power spectral density Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.395, year: 2005

  12. Migration experiences, employment status and psychological distress among Somali immigrants: a mixed-method international study.

    Science.gov (United States)

    Warfa, Nasir; Curtis, Sarah; Watters, Charles; Carswell, Ken; Ingleby, David; Bhui, Kamaldeep

    2012-09-07

    The discourse about mental health problems among migrants and refugees tends to focus on adverse pre-migration experiences; there is less investigation of the environmental conditions in which refugee migrants live, and the contrasts between these situations in different countries. This cross-national study of two samples of Somali refugees living in London (UK) and Minneapolis, Minnesota, (USA) helps to fill a gap in the literature, and is unusual in being able to compare information collected in the same way in two cities in different countries. There were two parts to the study, focus groups to gather in-depth qualitative data and a survey of health status and quantifiable demographic and material factors. Three of the focus groups involved nineteen Somali professionals and five groups included twenty-eight lay Somalis who were living in London and Minneapolis. The quantitative survey was done with 189 Somali respondents, also living in London and Minneapolis. We used the MINI International Neuropsychiatric Interview (MINI) to assess ICD-10 and DSM-IV mental disorders. The overall qualitative and quantitative results suggested that challenges to masculinity, thwarted aspirations, devalued refugee identity, unemployment, legal uncertainties and longer duration of stay in the host country account for poor psychological well-being and psychiatric disorders among this group. The use of a mixed-methods approach in this international study was essential since the quantitative and qualitative data provide different layers and depth of meaning and complement each other to provide a fuller picture of complex and multi-faceted life situations of refugees and asylum seekers. The comparison between the UK and US suggests that greater flexibility of access to labour markets for this refugee group might help to promote opportunities for better integration and mental well-being.

  13. The challenge of observation on livings things by employing an ultra small-angle neutron scattering method

    International Nuclear Information System (INIS)

    Koizumi, Satoshi; Motokawa, Ryuhei; Iwase, Hiroki; Miyamoto, Nobuyoshi; Tanaka, Kazuhiro; Masui, Tomomi; Iida, You; Yue, Zhao; Chiba, Kaori; Kumada, Takayuki; Yamaguchi, Daisuke; Hashimoto, Takeji

    2007-01-01

    To address the question as to how small-angle scattering is effectively applied to the cell, i.e., a hierarchically ordered system comprising multi-components of macro and small molecules, the size of which ranges from 100 μm to several μm, we reconstructed SANS-J (pinhole small-angle neutron scattering spectrometer at research reactor JRR3, Tokai) to focusing and polarized neutron small-angle spectrometer (SANS-J-II), by employing focusing neutron lenses and high resolution photomultiplier. Consequently, an accessible minimum wave number q min was improved from 3x10 -3 A -1 to medium ultra-small angle scattering of 3x10 -4 A -1 . The focusing USANS method, thus developed, is crucial to fill the gap in wave number q between those covered by a double crystal method and by a conventional pin-hole method. (author)

  14. Computer aided method for colour calibration and analysis of digital rock photographs

    Directory of Open Access Journals (Sweden)

    Matic Potočnik

    2015-12-01

    Full Text Available The methods used in geology to determine colour and colour coverage are expensive, time consuming, and/ or subjective. Estimates of colour coverage can only be approximate since they are based on rough comparisonbased measuring etalons and subjective estimation, which is dependent upon the skill and experience of the person performing the estimation. We present a method which accelerates, simplifis, and objectifis these tasks using a computer application. It automatically calibrates the colours of a digital photo, and enables the user to read colour values and coverage, even after returning from fild work. Colour identifiation is based on the Munsell colour system. For the purposes of colour calibration we use the X-Rite ColorChecker Passport colour chart placed onto the photographed scene. Our computer application detects the ColorChecker colour chart, and fids a colour space transformation to calibrate the colour in the photo. The user can then use the application to read colours within selected points or regions of the photo. The results of the computerised colour calibration were compared to the reference values of the ColorChecker chart. The values slightly deviate from the exact values, but the deviation is around the limit of human capability for visual comparison. We have devised an experiment, which compares the precision of the computerised colour analysis and manual colour analysis performed on a variety of rock samples with the help of geology students using Munsell Rock-color Chart. The analysis showed that the precision of manual comparative identifiation on multicoloured samples is somewhat problematic, since the choice of representative colours and observation points for a certain part of a sample are subjective. The computer based method has the edge in verifibility and repeatability of the analysis since the application the original photo to be saved with colour calibration, and tagging of colouranalysed points and regions.

  15. Assessment of intestinal permeability and bacterial translocation employing nuclear methods in murine mucositis

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, Rafaela M.; Takenaka, Isabella K.T.M.; Barros, Patricia A.V.; Moura, Livia P.; Contarini, Sara M.L.; Amorim, Juliana M.; Castilho, Raquel O.; Leite, Camila M.A.; Cardoso, Valbert N.; Diniz, Simone Odilia F. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Mg (Brazil)

    2017-07-01

    Full text: Introduction: Mucositis affects approximately 80% of patients who receive chemotherapy combinations. The lesions are painful, restrict food intake and make patients more susceptible to systemic infections. Some agents and strategies are being studied for controlling mucositis, none of them is used in clinical practice. In Minas Gerais, many studies have addressed the popular use of the plant Arrabidaea chica in the form of tea, to treat intestinal cramps and diarrhea, the main symptoms of mucositis. Objective: To evaluate the potential of Arrabidaea chica extract in the management of the integrity of the intestinal mucosa, using the experimental model of gut mucositis induced by 5-Fluorouracila (5-FU). Methods: The UFMG Ethics Committee for Animal Experimentation (CETEA/UFMG) approved this study (nº 411/2015). Male BALB/c mice between 6-8 weeks of age were randomly divided into four groups (n=9) as follows: 1. Control (CTL) - oral administration of saline solution (10 days); 2. A. chica (AC) - oral administration of A. chica extract (10 days); 3. Mucositis (MUC) - underwent mucositis (5-FU) (10 days); 4. Mucositis + A. chica (MUC+ AC) - underwent mucositis and received oral administration of A. chica extract (10 days). At the 7{sup th} day, mice in the MUC and MUC + AC groups received an intraperitoneal (IP) injection containing 300 mg/kg 5-FU, whereas the animals of the CTL and AC groups received a saline IP injection. After 72 hours (10{sup th} experimental day), intestinal permeability was determined by measuring the radioactivity diffusion in the blood after oral administration of diethylenetriaminepentaacetic acid (DTPA) labelled with technetium-99m ({sup 99m}Tc) and bacterial translocation was determined by measuring the radioactivity diffusion in the blood after oral administration of E. coli labelled with technetium-99m ({sup 99m}Tc). After 4 hours, the mice were euthanized and assessed for intestinal permeability, bacterial translocation and

  16. Assessment of intestinal permeability and bacterial translocation employing nuclear methods in murine mucositis

    International Nuclear Information System (INIS)

    Pessoa, Rafaela M.; Takenaka, Isabella K.T.M.; Barros, Patricia A.V.; Moura, Livia P.; Contarini, Sara M.L.; Amorim, Juliana M.; Castilho, Raquel O.; Leite, Camila M.A.; Cardoso, Valbert N.; Diniz, Simone Odilia F.

    2017-01-01

    Full text: Introduction: Mucositis affects approximately 80% of patients who receive chemotherapy combinations. The lesions are painful, restrict food intake and make patients more susceptible to systemic infections. Some agents and strategies are being studied for controlling mucositis, none of them is used in clinical practice. In Minas Gerais, many studies have addressed the popular use of the plant Arrabidaea chica in the form of tea, to treat intestinal cramps and diarrhea, the main symptoms of mucositis. Objective: To evaluate the potential of Arrabidaea chica extract in the management of the integrity of the intestinal mucosa, using the experimental model of gut mucositis induced by 5-Fluorouracila (5-FU). Methods: The UFMG Ethics Committee for Animal Experimentation (CETEA/UFMG) approved this study (nº 411/2015). Male BALB/c mice between 6-8 weeks of age were randomly divided into four groups (n=9) as follows: 1. Control (CTL) - oral administration of saline solution (10 days); 2. A. chica (AC) - oral administration of A. chica extract (10 days); 3. Mucositis (MUC) - underwent mucositis (5-FU) (10 days); 4. Mucositis + A. chica (MUC+ AC) - underwent mucositis and received oral administration of A. chica extract (10 days). At the 7 th day, mice in the MUC and MUC + AC groups received an intraperitoneal (IP) injection containing 300 mg/kg 5-FU, whereas the animals of the CTL and AC groups received a saline IP injection. After 72 hours (10 th experimental day), intestinal permeability was determined by measuring the radioactivity diffusion in the blood after oral administration of diethylenetriaminepentaacetic acid (DTPA) labelled with technetium-99m ( 99m Tc) and bacterial translocation was determined by measuring the radioactivity diffusion in the blood after oral administration of E. coli labelled with technetium-99m ( 99m Tc). After 4 hours, the mice were euthanized and assessed for intestinal permeability, bacterial translocation and intestinal histology

  17. High resolution seismic refraction method with multichannel digital data acquisition system; Digital ta channel sokutei system wo mochiita koseido kussetsuho jishin tansa

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, K [Oyo Corp., Tokyo (Japan)

    1997-05-27

    This paper introduces a multichannel digital data acquisition system and examples of measurements with the system in seismic exploration using the high resolution seismic refraction method. The high resolution seismic refraction system performs analyses nearly automatically by using a computer after initial travel time has been read. Therefore, the system requires high-accuracy travel time data, for which a multichannel digital measuring instrument developed recently for seismic exploration using the refraction method has been used for the measurement. The specification specifies the number of channels at 144 as a maximum, a sampling time of 62.5 {mu}sec to 4 m sec, the maximum number of sampling of 80,000 samples, and gain accuracy of {plus_minus} 1%. The system was used for surveying a tunnel having a maximum soil cover of about 800 m. The traverse line length is about 6 km, the distance between vibration receiving points is 50 m, and the number of vibration receiving points is 194. Executing measurements of single point system using GPS can derive accurate velocity in the vicinity of the basic face of the tunnel construction. Results were obtained from the investigation, which can serve more for actual construction work. 10 refs., 6 figs., 1 tab.

  18. Design and Implementation of Data Acquisition System Based on Digital Filtering Method for the Electrical Capacitance Tomography

    Directory of Open Access Journals (Sweden)

    LI Yang

    2017-02-01

    Full Text Available Aiming at the problem of high frequency noise interference in the ECT data acquisition system,on the basis of analysis of the ECT system data acquisition and control principles,we designed an improved distributed algorithm FIR low-pass digital filter combined with FPGA technology and digital filtering principle. The sampling frequency of the filter is 1 .5 MHz,the pass band cutoff frequency is 20MHz,and the design method is window function. We used the FDATooI toolbox in Matlab to extract and quantify the filter coefficients and the Quarters to simulate the simulation. Experimental results showed that the FIR digital filter can achieve the filtering function of the high frequency signal in the data acquisition system. Compared with the traditional DA algorithm,it has the advantages of small resource consumption and high acquisition speed and some other characteristics.

  19. Breast MRI, digital mammography and breast tomosynthesis: comparison of three methods for early detection of breast cancer.

    Science.gov (United States)

    Roganovic, Dragana; Djilas, Dragana; Vujnovic, Sasa; Pavic, Dag; Stojanov, Dragan

    2015-11-16

    Breast cancer is the most common malignancy in women and early detection is important for its successful treatment. The aim of this study was to investigate the sensitivity and specificity of three methods for early detection of breast cancer: breast magnetic resonance imaging (MRI), digital mammography, and breast tomosynthesis in comparison to histopathology, as well as to investigate the intraindividual variability between these modalities. We included 57 breast lesions, each detected by three diagnostic modalities: digital mammography, breast MRI, and breast tomosynthesis, and subsequently confirmed by histopathology. Breast Imaging-Reporting and Data System (BI-RADS) was used for characterizing the lesions. One experienced radiologist interpreted all three diagnostic modalities. Twenty-nine of the breast lesions were malignant while 28 were benign. The sensitivity for digital mammography, breast MRI, and breast tomosynthesis, was 72.4%, 93.1%, and 100%, respectively; while the specificity was 46.4%, 60.7%, and 75%, respectively. Receiver operating characteristics (ROC) curve analysis showed an overall diagnostic advantage of breast tomosynthesis over both breast MRI and digital mammography. The difference in performance between breast tomosynthesis and digital mammography was significant (p tomosynthesis and breast MRI was not significant (p=0.20).

  20. Breast MRI, digital mammography and breast tomosynthesis: comparison of three methods for early detection of breast cancer

    Directory of Open Access Journals (Sweden)

    Dragana Roganovic

    2015-11-01

    Full Text Available Breast cancer is the most common malignancy in women and early detection is important for its successful treatment. The aim of this study was to investigate the sensitivity and specificity of three methods for early detection of breast cancer: breast magnetic resonance imaging (MRI, digital mammography, and breast tomosynthesis in comparison to histopathology, as well as to investigate the intraindividual variability between these modalities.  We included 57 breast lesions, each detected by three diagnostic modalities: digital mammography, breast MRI, and breast tomosynthesis, and subsequently confirmed by histopathology. Breast Imaging-Reporting and Data System (BI-RADS was used for characterizing the lesions. One experienced radiologist interpreted all three diagnostic modalities. Twenty-nine of the breast lesions were malignant while 28 were benign. The sensitivity for digital mammography, breast MRI, and breast tomosynthesis, was 72.4%, 93.1%, and 100%, respectively; while the specificity was 46.4%, 60.7%, and 75%, respectively. Receiver operating characteristics (ROC curve analysis showed an overall diagnostic advantage of breast tomosynthesis over both breast MRI and digital mammography. The difference in performance between breast tomosynthesis and digital mammography was significant (p < 0.001, while the difference between breast tomosynthesis and breast MRI was not significant (p = 0.20. 

  1. Evaluation of DNBR calculation methods for advanced digital core protection system

    International Nuclear Information System (INIS)

    Ihn, W. K.; Hwang, D. H.; Pak, Y. H.; Yoon, T. Y.

    2003-01-01

    This study evaluated the on-line DNBR calculation methods for an advanced digital core protection system in PWR, i.e., subchannel analysis and group-channel analysis. The subchannel code MATRA and the four-channel codes CETOP-D and CETOP2 were used here. CETOP2 is most simplified DNBR analysis code which is implemented in core protection calculator in Korea standard nuclear power plants. The detailed subchannel code TORC was used as a reference calculation of DNBR. The DNBR uncertainty and margin were compared using allowable operating conditions at Yonggwang nuclear units 3-4. The MATRA code using a nine lumping-channel model resulted in smaller mean and larger standard deviation of the DNBR error distribution. CETOP-D and CETOP2 showed conservatively biased mean and relatively smaller standard deviation of the DNBR error distribution. MATRA and CETOP-D w.r.t CETOP2 showed significant increase of the DNBR available margin at normal operating condition. Taking account for the DNBR uncertainty, MATRA and CETOP-D over CETOP2 were estimated to increase the DNBR net margin by 2.5%-9.8% and 2.5%-3.3%, respectively

  2. A flexible and accurate digital volume correlation method applicable to high-resolution volumetric images

    Science.gov (United States)

    Pan, Bing; Wang, Bo

    2017-10-01

    Digital volume correlation (DVC) is a powerful technique for quantifying interior deformation within solid opaque materials and biological tissues. In the last two decades, great efforts have been made to improve the accuracy and efficiency of the DVC algorithm. However, there is still a lack of a flexible, robust and accurate version that can be efficiently implemented in personal computers with limited RAM. This paper proposes an advanced DVC method that can realize accurate full-field internal deformation measurement applicable to high-resolution volume images with up to billions of voxels. Specifically, a novel layer-wise reliability-guided displacement tracking strategy combined with dynamic data management is presented to guide the DVC computation from slice to slice. The displacements at specified calculation points in each layer are computed using the advanced 3D inverse-compositional Gauss-Newton algorithm with the complete initial guess of the deformation vector accurately predicted from the computed calculation points. Since only limited slices of interest in the reference and deformed volume images rather than the whole volume images are required, the DVC calculation can thus be efficiently implemented on personal computers. The flexibility, accuracy and efficiency of the presented DVC approach are demonstrated by analyzing computer-simulated and experimentally obtained high-resolution volume images.

  3. Decision Support System to Choose Digital Single Lens Camera with Simple Additive Weighting Method

    Directory of Open Access Journals (Sweden)

    Tri Pina Putri

    2016-11-01

    Full Text Available One of the technologies that evolve today is Digital Single Lens Reflex (DSLR camera. The number of products makes users have difficulties to choose the appropriate camera based on their criteria. Users may utilize several ways to help them choosing the intended camera such as using magazine, internet, and other media. This paper discusses about a web based decision support system to choose cameras by using SAW (Simple Additive Weighting method in order to make the decision process more effective and efficient. This system is expected to give recommendations about the camera which is appropriate with the user’s need and criteria based on the cost, the resolution, the feature, the ISO, and the censor. The system was implemented by using PHP and MySQL. Based on the result of questionnaire distributed to 20 respondents, 60% respondents agree that this decision support system can help users to choose the appropriate camera DSLR in accordance with the user’s need, 60% of respondents agree that this decision support system is more effective to choose DSLR camera and 75% of respondents agree that this system is more efficient. In addition, 60.55% of respondents agree that this system has met 5 Es Usability Framework.

  4. A limited memory BFGS method for a nonlinear inverse problem in digital breast tomosynthesis

    Science.gov (United States)

    Landi, G.; Loli Piccolomini, E.; Nagy, J. G.

    2017-09-01

    Digital breast tomosynthesis (DBT) is an imaging technique that allows the reconstruction of a pseudo three-dimensional image of the breast from a finite number of low-dose two-dimensional projections obtained by different x-ray tube angles. An issue that is often ignored in DBT is the fact that an x-ray beam is polyenergetic, i.e. it is composed of photons with different levels of energy. The polyenergetic model requires solving a large-scale, nonlinear inverse problem, which is more expensive than the typically used simplified, linear monoenergetic model. However, the polyenergetic model is much less susceptible to beam hardening artifacts, which show up as dark streaks and cupping (i.e. background nonuniformities) in the reconstructed image. In addition, it has been shown that the polyenergetic model can be exploited to obtain additional quantitative information about the material of the object being imaged. In this paper we consider the multimaterial polyenergetic DBT model, and solve the nonlinear inverse problem with a limited memory BFGS quasi-Newton method. Regularization is enforced at each iteration using a diagonally modified approximation of the Hessian matrix, and by truncating the iterations.

  5. Thermal monitoring as a method for estimation of technical state of digital devices

    Directory of Open Access Journals (Sweden)

    Lavrich Yu. N.

    2015-08-01

    Full Text Available Requirements to the reliability level of modern element base are so high that traditional methods of assessing the technical condition of electronics become ineffective, the modern theory of reliability has almost no practical applications [1], and reliability index does not reflect the true state of an electronic device due to an insufficient amount of information received during testing of electronic devices. The majority of modern electronics are limitedly easy-to-test. They are equipped with small number of tools for direct measurement that leads to a delayed troubleshooting and the inability to take measures efficiently. Despite the fact that new generations of electronics use modern components and new design technologies, their performance is still defined by two states — serviceability or failure, and the failure still happens unexpectedly. We may note, that failure is an uncontrolled result of an irreversible degradation process, taking place in time and having appropriate time parameters, but it's not the critical act. Research of various structural and hierarchical levels of functional units of digital electronics show that temperature control can be used for automatic condition monitoring of such devices in real time. As a generalized control parameter, it is advisable to use the temperature of the case of the element, and the case itself — as a generalized point.

  6. Investigation of Rock Failure Pattern in Creep by Digital Speckle Correlation Method

    Directory of Open Access Journals (Sweden)

    Yunliang Tan

    2013-01-01

    Full Text Available In order to study the mechanical characteristics from creep deformation to failure of rock, the tests of uniaxial compression and pushing steel-plate anchored in rock were performed, by using RLJW-2000 servo test synchronizing with Digital Speckle Correlation Method (DSCM. The investigations showed that for a uniaxial compressive specimen, when load arrived at 0.5σc, displacement clusters orderly formed, which was ahead of the macrocreep strain occurring in a slight jump mode when load arrived at 0.7σc. When the load level arrived at 0.8σc, displacement clusters gathered to be a narrow band. After that, the specimen abruptly fractured in a shear mode. In the creep pushing steel-plate test, when pushing force arrived at 25 kN, crack began to occur, the horizontal displacement field as well as shear strain field concentrated continuously along the interface between steel-plate and rock, and a new narrow concentrating band gathered in the upper layer. When pushing force arrived at 27.5 kN, another new narrow shear deformation band formed in the lower layer. Then, the steel-plate was pushed out quickly accompanying strong creep deformation.

  7. A basis of common approach to the development of universal steganalysis methods for digital images

    Directory of Open Access Journals (Sweden)

    Alla А. Kobozeva

    2014-12-01

    Full Text Available In this paper a new common approach to the organization of steganalysis in digital images is developed. New features of formal parameters defining the image are identified, theoretically grounded and practically tested. For the first time characteristics of mutual disposition of the left and right singular vectors corresponding to the largest singular value of the matrix (block of matrix of an image and the vector composed of the singular values obtained as a result of normal singular decomposition of the matrix (block matrix are obtained. It is shown that for the majority of the blocks of the original image (regardless of the storage format — lossy, lossless the angle between the left (right singular vector and the vector composed of singular numbers is determined by the angle between the n-optimal vector and the standard space basis of the corresponding dimension. It is shown that the discovered feature is violated for the mentioned formal parameters in the disturbed image. This is an indicator of integrity violation, particularly steganotransformation, and it can be used to develop new universal steganalysis methods and algorithms. Their efficiency does not depend on the specifics of steganoalgorithm used for insertion of additional information.

  8. Mapping Power Law Distributions in Digital Health Social Networks: Methods, Interpretations, and Practical Implications.

    Science.gov (United States)

    van Mierlo, Trevor; Hyatt, Douglas; Ching, Andrew T

    2015-06-25

    Social networks are common in digital health. A new stream of research is beginning to investigate the mechanisms of digital health social networks (DHSNs), how they are structured, how they function, and how their growth can be nurtured and managed. DHSNs increase in value when additional content is added, and the structure of networks may resemble the characteristics of power laws. Power laws are contrary to traditional Gaussian averages in that they demonstrate correlated phenomena. The objective of this study is to investigate whether the distribution frequency in four DHSNs can be characterized as following a power law. A second objective is to describe the method used to determine the comparison. Data from four DHSNs—Alcohol Help Center (AHC), Depression Center (DC), Panic Center (PC), and Stop Smoking Center (SSC)—were compared to power law distributions. To assist future researchers and managers, the 5-step methodology used to analyze and compare datasets is described. All four DHSNs were found to have right-skewed distributions, indicating the data were not normally distributed. When power trend lines were added to each frequency distribution, R(2) values indicated that, to a very high degree, the variance in post frequencies can be explained by actor rank (AHC .962, DC .975, PC .969, SSC .95). Spearman correlations provided further indication of the strength and statistical significance of the relationship (AHC .987. DC .967, PC .983, SSC .993, Ppower distributions across multiple DHSNs, each addressing a unique condition. Results indicate that despite vast differences in theme, content, and length of existence, DHSNs follow properties of power laws. The structure of DHSNs is important as it gives insight to researchers and managers into the nature and mechanisms of network functionality. The 5-step process undertaken to compare actor contribution patterns can be replicated in networks that are managed by other organizations, and we conjecture that

  9. Enhancing Digital Literacy and Learning among Adults with Blogs

    Science.gov (United States)

    Sharp, Laurie A.

    2017-01-01

    Digital literacy and learning among adults has been identified as an area requiring research. The purpose of the present study was to explore technology acceptance and digital collaborative learning experiences with blogs among adult learners. This analysis employed a quasi-experimental mixed-methods approach guided by a sociocultural theoretical…

  10. Method and apparatus for analog signal conditioner for high speed, digital x-ray spectrometer

    International Nuclear Information System (INIS)

    Warburton, W.K.; Hubbard, B.

    1999-01-01

    A signal processing system which accepts input from an x-ray detector-preamplifier and produces a signal of reduced dynamic range for subsequent analog-to-digital conversion is disclosed. The system conditions the input signal to reduce the number of bits required in the analog-to-digital converter by removing that part of the input signal which varies only slowly in time and retaining the amplitude of the pulses which carry information about the x-rays absorbed by the detector. The parameters controlling the signal conditioner's operation can be readily supplied in digital form, allowing it to be integrated into a feedback loop as part of a larger digital x-ray spectroscopy system. 13 figs

  11. A Search method for Scientific Data in Digital Libraries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Unlike the world wide web or general libraries, digital libraries typically serve a specialized community of experts sharing a relatively narrow focus, such as some...

  12. Seeking the balance between caregiving in dementia, family and employment: study protocol for a mixed methods study in Northern Germany.

    Science.gov (United States)

    Neubert, Lydia; König, Hans-Helmut; Brettschneider, Christian

    2018-02-27

    The debate on reconciliation between childcare and working has to be expanded to caregiving for the elderly, since the importance of informal caregiving will increase in the future due to populations' ageing and women's increasing labour force participation. Informal caregivers who are caring for the rising number of persons with dementia (PwD) are often female and subjected to high caregiving requirements. These are added to further demands emerging from their family and work life. How affected caregivers seek to balance those requirements depends on, inter alia, their own characteristics and the informal caregiving network to whom they relate. Both aspects were not yet considered in previous studies. This mixed methods study thus aims to explore the reconciliation between caregiving in dementia, family and employment by including different members of caregiving networks of home-dwelling PwD and by considering their personal characteristics. By purposive sampling, we include at least five caregiving networks of home-dwelling PwD; each of them consisting of at least three informal caregivers living in Northern Germany. Narrative interviews of participants will be recorded, transcribed verbatim and interpreted according to the Documentary Method (QUAL). By completing standardised questionnaires, participants will provide sociodemographic and psychographic data concerning themselves and the networks from whom they arise (quan). This supplemental, descriptive information will give further background to the themes and types emerging from the interviews. Hence, the quan-data enrich the QUAL-data by exploring the narratives of participants in the light of their personal and network-related characteristics. Ethical approval was obtained from the Ethics Committee of the German Society of Nursing Sciences. Study results will be disseminated through conference presentations and publications in peer-reviewed journals. DRKS00012929. © Article author(s) (or their employer(s

  13. Leveraging social and digital media for participant recruitment: A review of methods from the Bayley Short Form Formative Study.

    Science.gov (United States)

    Burke-Garcia, Amelia; Mathew, Sunitha

    2017-06-01

    Social media is increasingly being used in research, including recruitment. For the Bayley Short Form Formative Study, which was conducted under the the National Children's Study, traditional methods of recruitment proved to be ineffective. Therefore, digital media were identified as potential channels for recruitment. Results included successful recruitment of over 1800 infant and toddler participants to the Study. This paper outlines the methods, results, and future research opportunities.

  14. The Sociality of Gaming : A mixed methods approach to understanding digital gaming as a social leisure activity

    OpenAIRE

    Eklund, Lina

    2012-01-01

    This dissertation is an exploration of the practice of social digital gaming, using a mixed methods approach with complementary data and analytical methods. The main themes are the prevalence and meaning of gamers’ experiences of social gaming and the underlying structures limiting or assisting social gaming, both material and social. Applying an everyday perspective, focus is on gamers’ day-to-day practices and experiences. Studies I and II enquire into relational aspects of social gaming ba...

  15. The application of ethnographic method in the study of digital media

    OpenAIRE

    Amelia Capobianco

    2015-01-01

    Digital media raise methodological issues of some relevance. The following article tries to be a contribution to the qualitative analysis of Social Networks through the use of media ethnography. We deal with issues such as time and space and with how these dimension get transformed in digital environments; the very definition of environment and social network; an effective communication; the constant flow between online and off-line activities; the role of the “digital” researcher, his/her in...

  16. In-vitro evaluation of the accuracy of conventional and digital methods of obtaining full-arch dental impressions.

    Science.gov (United States)

    Ender, Andreas; Mehl, Albert

    2015-01-01

    To investigate the accuracy of conventional and digital impression methods used to obtain full-arch impressions by using an in-vitro reference model. Eight different conventional (polyether, POE; vinylsiloxanether, VSE; direct scannable vinylsiloxanether, VSES; and irreversible hydrocolloid, ALG) and digital (CEREC Bluecam, CER; CEREC Omnicam, OC; Cadent iTero, ITE; and Lava COS, LAV) full-arch impressions were obtained from a reference model with a known morphology, using a highly accurate reference scanner. The impressions obtained were then compared with the original geometry of the reference model and within each test group. A point-to-point measurement of the surface of the model using the signed nearest neighbour method resulted in a mean (10%-90%)/2 percentile value for the difference between the impression and original model (trueness) as well as the difference between impressions within a test group (precision). Trueness values ranged from 11.5 μm (VSE) to 60.2 μm (POE), and precision ranged from 12.3 μm (VSE) to 66.7 μm (POE). Among the test groups, VSE, VSES, and CER showed the highest trueness and precision. The deviation pattern varied with the impression method. Conventional impressions showed high accuracy across the full dental arch in all groups, except POE and ALG. Conventional and digital impression methods show differences regarding full-arch accuracy. Digital impression systems reveal higher local deviations of the full-arch model. Digital intraoral impression systems do not show superior accuracy compared to highly accurate conventional impression techniques. However, they provide excellent clinical results within their indications applying the correct scanning technique.

  17. 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

    This paper reviews recent advances in the field of digital spectrometry made by researchers at X-Ray Instrumentation Associates. All XIA spectrometers are based on a core architecture, which employs digitizing the input signal without shaping and applying all basic data processing in real time to the digital data stream coming out of the wave form digitizer. The real-time digital data processing includes filtering, triggering, pileup rejection, and even pulse shape analysis. In this paper we will describe some of those methods that go beyond emulating a conventional analog system in a digital environment. Rather we will concentrate mainly on methods that have no real equivalent in the analog world. In conventional spectrometers pulse pileup recognition is hardwired and serves a single purpose, namely to reject signals that occur too close to each other to allow for a precise measurement of their amplitude. For a digital device, which can also record wave forms, that would be an unfortunate limitation. The study of very short-lived radioactive isotopes is a case in point. If such an isotope is implanted into a detector in which it then decays by charged particle emission, the signature for the sought-after isotope is that of an implant pulse followed by one or more decay pulses from the isotope and its daughters. If the decay products can be absorbed in the same detector channel, as is the case for proton and alpha emitters in a Si-strip detector, then the isotope decay will show up as a pulse train coming from that detector channel. The difficulty usually is to find the few isotopes of interest amongst a huge background of long-lived or stable isotopes. With programmable pileup recognition logic it is possible to trigger specifically on pulse trains, rather than single pulses, thereby picking out very selectively the isotopes of interest. Analyzing the pulse shape of the incoming preamplifier signal proves to be very useful in many applications. The most obvious

  18. Method of correction of motive sphere for deaf schoolboys during an orientation on employments on health tourism

    Directory of Open Access Journals (Sweden)

    Baikina N.G.

    2012-08-01

    Full Text Available The purpose of work consists in development of method of correction of motive sphere and linguistic development running on speed and endurance for deaf schoolboys which are engaged in health tourism. In an experiment deaf schoolboys took part 12-14 years. The sizes of latent period of reaction are set on a light signal and change in the indexes of nervous muscle vehicle. Bases of preparation of schoolboys are recommended on tactic of orientation on employments by health tourism. The features of speeding up and endurance are selected for deaf and hearings schoolboys on employments on an orientation. It is set that the correction of motive sphere must be carried out on the basis of running preparation - on speed and endurance. It is thus necessary to extend and choose the volume of initial verbal information - verbal, writing, haptic, gesticulation. It is marked about importance of introduction of sporting technicals in the process of implementation at run, multiple to repeat verbal information about logic of inversely connect actions of student. It is set that playing, repeated, competition and circular methods must be combined with verbal components in all of accessible forms. Also, in combination with a show and operative correction of their activity.

  19. [Digital luminescence radiography. A new method of study in thoracic diagnosis at the intensive care unit].

    Science.gov (United States)

    Witte, G; Pothmann, W; Bause, H; Nicolas, V; Schulte am Esch, J; Bücheler, E

    1989-02-01

    The digital luminescence-radiography (DLR) technique relies on a complete digitalization of the X-ray image. Luminescence crystals on the imaging plate serve as an energy reservoir following their exposure to ionized radiation from any conventional X-ray source. A Helium-Neon laser stimulates the electrons in their high energy bands and therefore will be dropped back emitting luminescence. This luminescence is digitized by the DLR-System thus delivering a complete digital image to the image processor for subsequent processing and evaluation. The processed digital image is then recorded on a conventional film or a monitor screen. More than 3000 chest examinations using DLR have been performed on intensive care unit (ICU) patients at the University Hospital Eppendorf following the first eleven months since the clinical introduction of this new technique. The positive aspects of DLR such as high-contrast resolution and optimal reproducibility were clinically evaluated under ICU conditions. It was shown that DLR greatly improves the quality of the chest X-rays of all ICU patients and offers the following advantages: reproducibility, lateral chest projection, no insufficient exposure, reduction of exposure dose, electronical post-processing and storage, quality preserving digital storage and copying.

  20. Implementation of a disability management policy in a large healthcare employer: a quasi-experimental, mixed-methods evaluation.

    Science.gov (United States)

    Mustard, Cameron A; Skivington, Kathryn; Lay, Morgan; Lifshen, Marni; Etches, Jacob; Chambers, Andrea

    2017-06-17

    This study describes the process and outcomes of the implementation of a strengthened disability management policy in a large Canadian healthcare employer. Key elements of the strengthened policy included an emphasis on early contact, the training of supervisors and the integration of union representatives in return-to-work (RTW) planning. The study applied mixed methods, combining a process evaluation within the employer and a quasi-experimental outcome evaluation between employers for a 3-year period prior to and following policy implementation in January 2012. Staff in the implementation organisation (n=4000) and staff in a peer group of 29 large hospitals (n=1 19 000). Work disability episode incidence and duration. Both qualitative and quantitative measures of the implementation process were predominantly positive. Over the 6-year observation period, there were 624 work disability episodes in the organisation and 8604 in the comparison group of 29 large hospitals. The annual per cent change in episode incidence in the organisation was -5.6 (95% CI -9.9 to -1.1) comparable to the annual per cent change in the comparison group: -6.2 (-7.2 to -5.3). Disability episode durations also declined in the organisation, from a mean of 19.4 days (16.5, 22.3) in the preintervention period to 10.9 days (8.7, 13.2) in the postintervention period. Reductions in disability durations were also observed in the comparison group: from a mean of 13.5 days (12.9, 14.1) in the 2009-2011 period to 10.5 days (9.9, 11.1) in the 2012-2014 period. The incidence of work disability episodes and the durations of work disability declined strongly in this hospital sector over the 6-year observation period. The implementation of the organisation's RTW policy was associated with larger reductions in disability durations than observed in the comparison group. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial

  1. Design of Service Oriented Architecture(SOA)-based Software Vulnerability Analysis Method for Digital I and C System in NPP

    International Nuclear Information System (INIS)

    Song, J. G.; Lee, C. K.; Kwon, K. C.; Kim, K. H.; Kim, S. S.

    2011-01-01

    Diverse cyber security issues due to the vulnerability of the digital control systems have been brought up in the existing IT environments while advancement and propagation of digital I and C systems have improved convenience through automation. The recent example of Stuxnet proved that stability in the digital I and C system could not be secured due to an air gap of physical security elements. Therefore, it is required to discover new approaches toward cyber security that will overcome the limitation on security in a closed environment. In particular, there is a rapid increase in the importance of cyber security seen in guidelines published by IAEA and U.S. NRC shows that cyber security as well as physical security draws worldwide attention as a key component for nuclear system safety. To incorporate the new guide requirement, cyber security threats are analyzed by ITbase security elements for finding best practice approaches. The vulnerabilities identified by the general security threats and defined mitigation activities can include many different methods and strategies. This research suggests a method for analyzing vulnerability and assessment the nuclear digital I and C cyber security

  2. Design of Service Oriented Architecture(SOA)-based Software Vulnerability Analysis Method for Digital I and C System in NPP

    Energy Technology Data Exchange (ETDEWEB)

    Song, J. G.; Lee, C. K.; Kwon, K. C. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, K. H. [Shinsegae Information and Communication Co., Seoul (Korea, Republic of); Kim, S. S. [Hannam University, Daejeon (Korea, Republic of)

    2011-05-15

    Diverse cyber security issues due to the vulnerability of the digital control systems have been brought up in the existing IT environments while advancement and propagation of digital I and C systems have improved convenience through automation. The recent example of Stuxnet proved that stability in the digital I and C system could not be secured due to an air gap of physical security elements. Therefore, it is required to discover new approaches toward cyber security that will overcome the limitation on security in a closed environment. In particular, there is a rapid increase in the importance of cyber security seen in guidelines published by IAEA and U.S. NRC shows that cyber security as well as physical security draws worldwide attention as a key component for nuclear system safety. To incorporate the new guide requirement, cyber security threats are analyzed by ITbase security elements for finding best practice approaches. The vulnerabilities identified by the general security threats and defined mitigation activities can include many different methods and strategies. This research suggests a method for analyzing vulnerability and assessment the nuclear digital I and C cyber security

  3. Innovation Online Teaching Module Plus Digital Engineering Kit with Proteus Software through Hybrid Learning Method to Improve Student Skills

    Science.gov (United States)

    Kholis, Nur; Syariffuddien Zuhrie, Muhamad; Rahmadian, Reza

    2018-04-01

    Demands the competence (competence) needs of the industry today is a competent workforce to the field of work. However, during this lecture material Digital Engineering (Especially Digital Electronics Basics and Digital Circuit Basics) is limited to the delivery of verbal form of lectures (classical method) is dominated by the Lecturer (Teacher Centered). Though the subject of Digital Engineering requires learning tools and is required understanding of electronic circuits, digital electronics and high logic circuits so that learners can apply in the world of work. One effort to make it happen is by creating an online teaching module and educational aids (Kit) with the help of Proteus software that can improve the skills of learners. This study aims to innovate online teaching modules plus kits in Proteus-assisted digital engineering courses through hybrid learning approaches to improve the skills of learners. The process of innovation is done by considering the skills and mastery of the technology of students (students) Department of Electrical Engineering - Faculty of Engineering – Universitas Negeri Surabaya to produce quality graduates Use of online module plus Proteus software assisted kit through hybrid learning approach. In general, aims to obtain adequate results with affordable cost of investment, user friendly, attractive and interactive (easily adapted to the development of Information and Communication Technology). With the right design, implementation and operation, both in the form of software both in the form of Online Teaching Module, offline teaching module, Kit (Educational Viewer), and e-learning learning content (both online and off line), the use of the three tools of the expenditure will be able to adjust the standard needs of Information and Communication Technology world, both nationally and internationally.

  4. An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems

    International Nuclear Information System (INIS)

    Bouwman, R; Broeders, M; Van Engen, R; Young, K; Lazzari, B; Ravaglia, V

    2009-01-01

    According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does not discriminate sufficiently between systems with and without additional noise besides quantum noise. This paper attempts to give an alternative and relatively simple method for noise analysis which can divide noise into electronic noise, structured noise and quantum noise. Quantum noise needs to be the dominant noise source in clinical images for optimal performance of a digital mammography system, and therefore the amount of electronic and structured noise should be minimal. For several digital mammography systems, the noise was separated into components based on the measured pixel value, standard deviation (SD) of the image and the detector entrance dose. The results showed that differences between systems exist. Our findings confirm that the proposed method is able to discriminate systems based on their noise performance and is able to detect possible quality problems. Therefore, we suggest to replace the current method for noise analysis as described in the European Guidelines by the alternative method described in this paper.

  5. Adaptive thresholding and dynamic windowing method for automatic centroid detection of digital Shack-Hartmann wavefront sensor

    International Nuclear Information System (INIS)

    Yin Xiaoming; Li Xiang; Zhao Liping; Fang Zhongping

    2009-01-01

    A Shack-Hartmann wavefront sensor (SWHS) splits the incident wavefront into many subsections and transfers the distorted wavefront detection into the centroid measurement. The accuracy of the centroid measurement determines the accuracy of the SWHS. Many methods have been presented to improve the accuracy of the wavefront centroid measurement. However, most of these methods are discussed from the point of view of optics, based on the assumption that the spot intensity of the SHWS has a Gaussian distribution, which is not applicable to the digital SHWS. In this paper, we present a centroid measurement algorithm based on the adaptive thresholding and dynamic windowing method by utilizing image processing techniques for practical application of the digital SHWS in surface profile measurement. The method can detect the centroid of each focal spot precisely and robustly by eliminating the influence of various noises, such as diffraction of the digital SHWS, unevenness and instability of the light source, as well as deviation between the centroid of the focal spot and the center of the detection area. The experimental results demonstrate that the algorithm has better precision, repeatability, and stability compared with other commonly used centroid methods, such as the statistical averaging, thresholding, and windowing algorithms.

  6. Development and evaluation of a digital dental modeling method based on grating projection and reverse engineering software.

    Science.gov (United States)

    Zhou, Qin; Wang, Zhenzhen; Chen, Jun; Song, Jun; Chen, Lu; Lu, Yi

    2016-01-01

    For reasons of convenience and economy, attempts have been made to transform traditional dental gypsum casts into 3-dimensional (3D) digital casts. Different scanning devices have been developed to generate digital casts; however, each has its own limitations and disadvantages. The purpose of this study was to develop an advanced method for the 3D reproduction of dental casts by using a high-speed grating projection system and noncontact reverse engineering (RE) software and to evaluate the accuracy of the method. The methods consisted of 3 main steps: the scanning and acquisition of 3D dental cast data with a high-resolution grating projection system, the reconstruction and measurement of digital casts with RE software, and the evaluation of the accuracy of this method using 20 dental gypsum casts. The common anatomic landmarks were measured directly on the gypsum casts with a Vernier caliper and on the 3D digital casts with the Geomagic software measurement tool. Data were statistically assessed with the t test. The grating projection system had a rapid scanning speed, and smooth 3D dental casts were obtained. The mean differences between the gypsum and 3D measurements were approximately 0.05 mm, and no statistically significant differences were found between the 2 methods (P>.05), except for the measurements of the incisor tooth width and maxillary arch length. A method for the 3D reconstruction of dental casts was developed by using a grating projection system and RE software. The accuracy of the casts generated using the grating projection system was comparable with that of the gypsum casts. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  7. Pixel-size-maintained image reconstruction of digital holograms on arbitrarily tilted planes by the angular spectrum method.

    Science.gov (United States)

    Jeong, Seung Jun; Hong, Chung Ki

    2008-06-01

    We present an effective method for the pixel-size-maintained reconstruction of images on arbitrarily tilted planes in digital holography. The method is based on the plane wave expansion of the diffraction wave fields and the three-axis rotation of the wave vectors. The images on the tilted planes are reconstructed without loss of the frequency contents of the hologram and have the same pixel sizes. Our method shows good results in the extreme cases of large tilting angles and in the region closer than the paraxial case. The effectiveness of the method is demonstrated by both simulation and experiment.

  8. The reality of virtual anthropology: Comparing digitizer and laser scan data collection methods for the quantitative assessment of the cranium.

    Science.gov (United States)

    Algee-Hewitt, Bridget F B; Wheat, Amber D

    2016-05-01

    The use of geometric morphometry to study cranial variation has steadily grown in appeal over the past decade in biological anthropology. Publication trends suggest that the most popular methods for three-dimensional data acquisition involve landmark-based coordinate data collection using a digitizer. Newer laser scan approaches are seeing increasing use, owing to the benefits that densely sampled data offer. While both of these methods have their utility, research that investigates their compatibility is lacking. The purpose of this project is to compare, quantitatively, craniometrics collected with a digitizer against data extracted from laser scans using the same individuals and laboratory conditions. Three-dimensional (x,y,z) coordinates and traditional inter-landmark distances (ILDs) were obtained with a Microscribe digitizer and 360° color models produced from NextEngine laser scans for 38 adult crania representing five cemeteries from the ADBOU skeletal collection in Denmark. Variance-based tests were performed to evaluate the disagreement between data collected with a digitizer and from laser scan models. Consideration was given to differences among landmarks by type, between ILDs calculated from landmark coordinates, and in morphology for the cemetery populations. Further, the reliability of laser scan data collection was assessed by intra-observer error tests. Researchers should be aware of the potential error associated with the use of Types II and III landmarks and the limitations on reliability imposed by object-to-scanner placement. This project reveals how laser scans can provide a valuable digital archive of cranial material that can be reasonably exploited for the "virtual" collection of coordinates and the calculation of ILDs. © 2015 Wiley Periodicals, Inc.

  9. The Open Method of Co-ordination and the Analysis of Mutual Learning Processes of the European Employment Strategy

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    2005-01-01

    The purpose of this paper is to address two normative and interlinked methodological and theoretical questions concerning the Open Method of Coordination (OMC): First, what is the most appropriate approach to learning in the analyses of the processes of the European Employment Strategy (EES......)? Second, how should mutual learning processes be diffused among the Member States in order to be efficient? In answering these two questions the paper draws on a social constructivist approach to learning thereby contributing to the debate about learning in the political science literature. At the same...... time, based on the literature and participatory observations, it is concluded that the learning effects of the EES are probably somewhat larger than what is normally suggested, but that successful diffusion still depends on a variety of contextual factors. At the end of the paper a path for empirical...

  10. A method for digital image registration using a mathematical programming technique

    Science.gov (United States)

    Yao, S. S.

    1973-01-01

    A new algorithm based on a nonlinear programming technique to correct the geometrical distortions of one digital image with respect to another is discussed. This algorithm promises to be superior to existing ones in that it is capable of treating localized differential scaling, translational and rotational errors over the whole image plane. A series of piece-wise 'rubber-sheet' approximations are used, constrained in such a manner that a smooth approximation over the entire image can be obtained. The theoretical derivation is included. The result of using the algorithm to register four channel S065 Apollo IX digitized photography over Imperial Valley, California, is discussed in detail.

  11. Experimental evaluation of neural probe’s insertion induced injury based on digital image correlation method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenguang, E-mail: zhwg@sjtu.edu.cn; Ma, Yakun; Li, Zhengwei [State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2016-01-15

    Purpose: The application of neural probes in clinic has been challenged by probes’ short lifetime when implanted into brain tissue. The primary goal is to develop an evaluation system for testing brain tissue injury induced by neural probe’s insertion using microscope based digital image correlation method. Methods: A brain tissue phantom made of silicone rubber with speckle pattern on its surface was fabricated. To obtain the optimal speckle pattern, mean intensity gradient parameter was used for quality assessment. The designed testing system consists of three modules: (a) load module for simulating neural electrode implantation process; (b) data acquisition module to capture micrographs of speckle pattern and to obtain reactive forces during the insertion of the probe; (c) postprocessing module for extracting tissue deformation information from the captured speckle patterns. On the basis of the evaluation system, the effects of probe wedge angle, insertion speed, and probe streamline on insertion induced tissue injury were investigated. Results: The optimal quality speckle pattern can be attained by the following fabrication parameters: spin coating rate—1000 r/min, silicone rubber component A: silicone rubber component B: softener: graphite = 5 ml: 5 ml: 2 ml: 0.6 g. The probe wedge angle has a significant effect on tissue injury. Compared to wedge angle 40° and 20°, maximum principal strain of 60° wedge angle was increased by 40.3% and 87.5%, respectively; compared with a relatively higher speed (500 μm/s), the maximum principle strain within the tissue induced by slow insertion speed (100 μm/s) was increased by 14.3%; insertion force required by probe with convex streamline was smaller than the force of traditional probe. Based on the experimental results, a novel neural probe that has a rounded tip covered by a biodegradable silk protein coating with convex streamline was proposed, which has both lower insertion and micromotion induced tissue

  12. Expert and crowd-sourced validation of an individualized sleep spindle detection method employing complex demodulation and individualized normalization

    Directory of Open Access Journals (Sweden)

    Laura eRay

    2015-09-01

    Full Text Available A spindle detection method was developed that: 1 extracts the signal of interest (i.e., spindle-related phasic changes in sigma relative to ongoing background sigma activity using complex demodulation, 2 accounts for variations of spindle characteristics across the night, scalp derivations and between individuals, and 3 employs a minimum number of sometimes arbitrary, user-defined parameters. Complex demodulation was used to extract instantaneous power in the spindle band. To account for intra- and inter-individual differences, the signal was z-score transformed using a 60s sliding window, per channel, over the course of the recording. Spindle events were detected with a z-score threshold corresponding to a low probability (e.g., 99th percentile. Spindle characteristics, such as amplitude, duration and oscillatory frequency, were derived for each individual spindle following detection, which permits spindles to be subsequently and flexibly categorized as slow or fast spindles from a single detection pass. Spindles were automatically detected in 15 young healthy subjects. Two experts manually identified spindles from C3 during Stage 2 sleep, from each recording; one employing conventional guidelines, and the other, identifying spindles with the aid of a sigma (11-16 Hz filtered channel. These spindles were then compared between raters and to the automated detection to identify the presence of true positives, true negatives, false positives and false negatives. This method of automated spindle detection resolves or avoids many of the limitations that complicate automated spindle detection, and performs well compared to a group of non-experts, and importantly, has good external validity with respect to the extant literature in terms of the characteristics of automatically detected spindles.

  13. The Employer Potential of MOOCs: A Mixed-Methods Study of Human Resource Professionals' Thinking on MOOCs

    Science.gov (United States)

    Radford, Alexandria Walton; Robles, Jessica; Cataylo, Stacey; Horn, Laura; Thornton, Jessica; Whitfield, Keith E.

    2014-01-01

    While press coverage of MOOCs (massive open online courses) has been considerable and major MOOC providers are beginning to realize that employers may be a market for their courses, research on employers' receptivity to using MOOCs is scarce. To help fill this gap, the Finding and Developing Talent study surveyed 103 employers and interviewed a…

  14. Quantitative assessment of cerebral blood flow employing the Rutland method using N-isopropyl-(123I)-p-iodoamphetamine

    International Nuclear Information System (INIS)

    Aoki, Shigeru; Kitano, Tokio.

    1992-01-01

    The purpose of this study is to evaluate clinical usefulness as the quantitative assessment of the cerebral blood flow by venous sampling supersede arterial sampling using N-isopropyl-( 123 I)-p-iodoamphetamine (IMP) and single-photon emission computed tomography. The method employed Ono's report using the Rutland method. The mean value of total cerebral blood flow by arterial sampling was 388.0±79.4 (standard deviation) ml/min, and that by venous sampling was 448.5±110.3 ml/min. The value of temporal lobe, including basal ganglia where there was no evidence of neurological, electroencephalographic, and other imaging findings was 44.0±3.8 ml/100g/min using arterial sampling and 49.7±6.0 ml/100g/min using venous sampling. (n=22, mean age 57.6) The value of cases with poor peripheral circulation varied a great deal between the arterial and venous samplings. There was a good correlation between arterial and venous samplings in 76 patients without poor peripheral circulation. In conclusion, this method is available for noninvasive quantitative assessment of the cerebral blood flow in patients without poor peripheral circulation. (author)

  15. A high-speed bioelectrical impedance spectroscopy system based on the digital auto-balancing bridge method

    International Nuclear Information System (INIS)

    Li, Nan; Xu, Hui; Zhou, Zhou; Wang, Wei; Qiao, Guofeng; Li, David D-U

    2013-01-01

    A novel bioelectrical impedance spectroscopy system based on the digital auto-balancing bridge method improved from the conventional analogue auto-balancing method is presented for bioelectrical impedance measurements. The hardware of the proposed system consists of a reference source, a null detector, a variable source, a field programmable gate array, a clock generator, a flash and a USB controller. Software implemented in the field programmable gate array includes three major blocks: clock management, peripheral control and digital signal processing. The principle and realization of the least-mean-squares-based digital auto-balancing algorithm is introduced in detail. The performances of our system were examined by comparing with a commercial impedance analyzer. The results reveal that the proposed system has high speed (less than 3.5 ms per measurement) and high accuracy in the frequency range of 1 kHz–10 MHz. Compared with the commercial instrument based on the traditional analogue auto-balancing method, our system shows advantages in measurement speed, compactness and flexibility, making it suitable for various bioelectrical impedance measurement applications. (paper)

  16. Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

    Directory of Open Access Journals (Sweden)

    Fan Liu

    2015-02-01

    Full Text Available In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system (EFCS equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method (HQRM is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model, comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric turbulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness compliance of the airplane can be evaluated relying on the relevant regulations for handling qualities (HQ rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

  17. A highly sensitive and specific method for the screening detection of genetically modified organisms based on digital PCR without pretreatment.

    Science.gov (United States)

    Fu, Wei; Zhu, Pengyu; Wang, Chenguang; Huang, Kunlun; Du, Zhixin; Tian, Wenying; Wang, Qin; Wang, Huiyu; Xu, Wentao; Zhu, Shuifang

    2015-08-04

    Digital PCR has developed rapidly since it was first reported in the 1990 s. It was recently reported that an improved method facilitated the detection of genetically modified organisms (GMOs). However, to use this improved method, the samples must be pretreated, which could introduce inaccuracy into the results. In our study, we explored a pretreatment-free digital PCR detection method for the screening for GMOs. We chose the CaMV35s promoter and the NOS terminator as the templates in our assay. To determine the specificity of our method, 9 events of GMOs were collected, including MON810, MON863, TC1507, MIR604, MIR162, GA21, T25, NK603 and Bt176. Moreover, the sensitivity, intra-laboratory and inter-laboratory reproducibility of our detection method were assessed. The results showed that the limit of detection of our method was 0.1%, which was lower than the labeling threshold level of the EU. The specificity and stability among the 9 events were consistent, respectively. The intra-laboratory and inter-laboratory reproducibility were both good. Finally, the perfect fitness for the detection of eight double-blind samples indicated the good practicability of our method. In conclusion, the method in our study would allow more sensitive, specific and stable screening detection of the GMO content of international trading products.

  18. Methods for small RNA preparation for digital gene expression profiling by next-generation sequencing

    NARCIS (Netherlands)

    Linsen, S.E.V.; Cuppen, E.

    2012-01-01

    Digital gene expression (DGE) profiling techniques are playing an eminent role in the detection, localization, and differential expression quantification of many small RNA species, including microRNAs (1-3). Procedures in small RNA library preparation techniques typically include adapter ligation by

  19. Algorithmic impediments filtration using the α-truncated mean method in resolver-to-digital converter

    Directory of Open Access Journals (Sweden)

    Gordiyenko V. I.

    2009-02-01

    Full Text Available A test diagram of the microcontroller-type resolver-to-digital converter and algorithms for impediments filtration therein are developed. Experimental verification of the α-truncated mean algorithm intended for the suppression of impulse and noise interference is conducted. The test results are given.

  20. Design of Two-channel Half-band Bank of Digital Filters using Optimization Methods

    Czech Academy of Sciences Publication Activity Database

    Gescheidtová, E.; Kubásek, J.; Smékal, Z.; Bartušek, Karel

    2007-01-01

    Roč. 40, č. 1 (2007), s. 71-79 ISSN 1738-6438 R&D Projects: GA ČR(CZ) GA102/07/0389; GA ČR(CZ) GA102/07/1086 Institutional research plan: CEZ:AV0Z20650511 Keywords : criterial function * transfer function * bank of digital filters Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  1. A second pass correction method for calcification artifacts in digital breast tomosynthesis

    NARCIS (Netherlands)

    Erhard, K.; Grass, M.; Nielsen, T.

    2011-01-01

    Digital breast tomosynthesis (DBT) aims for improving the diagnosis of breast cancer and reducing the false positive rates by going from 2D projection mammography to 3D volume information. With the acquisition of a series of projection images, taken over a limited angular range, DBT allows for

  2. Holistic and Individualistic Evaluations of Digital Visual Art Portfolios: A Mixed Methods Study

    Science.gov (United States)

    Cavill, William D., Jr.

    2017-01-01

    The high-stakes nature of portfolio evaluation makes it necessary to perform such assessments in the fairest and most equitable manner possible. Determining whether or not there is a difference between holistically and individualistically derived scores for digital visual art portfolios and how those differences can be explained was the focus of…

  3. Reduced complexity digital back-propagation methods for optical communication systems

    NARCIS (Netherlands)

    Napoli, A.; Maalej, Z.; Sleiffer, V.A.J.M.; Kuschnerov, M.; Rafique, D.; Timmers, E.; Spinnler, B.; Rahman, T.; Coelho, L.D.; Hanik, N.

    2014-01-01

    Next-generation optical communication systems will continue to push the ( bandwidth $cdot$ distance) product towards its physical limit. To address this enormous demand, the usage of digital signal processing together with advanced modulation formats and coherent detection has been proposed to

  4. 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.)

  5. Advancing Collaboration between School- and Agency-Employed School-Based Social Workers: A Mixed-Methods Comparison of Competencies and Preparedness

    Science.gov (United States)

    Bronstein, Laura R.; Ball, Annahita; Mellin, Elizabeth A.; Wade-Mdivanian, Rebecca; Anderson-Butcher, Dawn

    2011-01-01

    The purpose of this article is to share results of a mixed-methods research study designed to shed light on similarities and differences between school-employed and agency-employed school-based social workers' preparation and practice as a precursor for collaboration in expanded school mental health. Online survey data from a national sample of…

  6. Teaching Dental Students to Understand the Temporomandibular Joint Using MRI: Comparison of Conventional and Digital Learning Methods.

    Science.gov (United States)

    Arús, Nádia A; da Silva, Átila M; Duarte, Rogério; da Silveira, Priscila F; Vizzotto, Mariana B; da Silveira, Heraldo L D; da Silveira, Heloisa E D

    2017-06-01

    The aims of this study were to evaluate and compare the performance of dental students in interpreting the temporomandibular joint (TMJ) with magnetic resonance imaging (MRI) scans using two learning methods (conventional and digital interactive learning) and to examine the usability of the digital learning object (DLO). The DLO consisted of tutorials about MRI and anatomic and functional aspects of the TMJ. In 2014, dental students in their final year of study who were enrolled in the elective "MRI Interpretation of the TMJ" course comprised the study sample. After exclusions for nonattendance and other reasons, 29 of the initial 37 students participated in the study, for a participation rate of 78%. The participants were divided into two groups: a digital interactive learning group (n=14) and a conventional learning group (n=15). Both methods were assessed by an objective test applied before and after training and classes. Aspects such as support and training requirements, complexity, and consistency of the DLO were also evaluated using the System Usability Scale (SUS). A significant between-group difference in the posttest results was found, with the conventional learning group scoring better than the DLO group, indicated by mean scores of 9.20 and 8.11, respectively, out of 10. However, when the pretest and posttest results were compared, both groups showed significantly improved performance. The SUS score was 89, which represented a high acceptance of the DLO by the users. The students who used the conventional method of learning showed superior performance in interpreting the TMJ using MRI compared to the group that used digital interactive learning.

  7. Using digital photography in a clinical setting: a valid, accurate, and applicable method to assess food intake.

    Science.gov (United States)

    Winzer, Eva; Luger, Maria; Schindler, Karin

    2018-06-01

    Regular monitoring of food intake is hardly integrated in clinical routine. Therefore, the aim was to examine the validity, accuracy, and applicability of an appropriate and also quick and easy-to-use tool for recording food intake in a clinical setting. Two digital photography methods, the postMeal method with a picture after the meal, the pre-postMeal method with a picture before and after the meal, and the visual estimation method (plate diagram; PD) were compared against the reference method (weighed food records; WFR). A total of 420 dishes from lunch (7 weeks) were estimated with both photography methods and the visual method. Validity, applicability, accuracy, and precision of the estimation methods, and additionally food waste, macronutrient composition, and energy content were examined. Tests of validity revealed stronger correlations for photography methods (postMeal: r = 0.971, p < 0.001; pre-postMeal: r = 0.995, p < 0.001) compared to the visual estimation method (r = 0.810; p < 0.001). The pre-postMeal method showed smaller variability (bias < 1 g) and also smaller overestimation and underestimation. This method accurately and precisely estimated portion sizes in all food items. Furthermore, the total food waste was 22% for lunch over the study period. The highest food waste was observed in salads and the lowest in desserts. The pre-postMeal digital photography method is valid, accurate, and applicable in monitoring food intake in clinical setting, which enables a quantitative and qualitative dietary assessment. Thus, nutritional care might be initiated earlier. This method might be also advantageous for quantitative and qualitative evaluation of food waste, with a resultantly reduction in costs.

  8. Collaborative Research in the Digital Humanities

    CERN Document Server

    Deegan, Marilyn

    2012-01-01

    Collaboration within digital humanities is both a pertinent and a pressing topic as the traditional mode of the humanist, working alone in his or her study, is supplemented by explicitly co-operative, interdependent and collaborative research. This is particularly true where computational methods are employed in large-scale digital humanities projects. This book, which celebrates the contributions of Harold Short to this field, presents fourteen essays by leading authors in the digital humanities. It addresses several issues of collaboration, from the multiple perspectives of institutions, pro

  9. Employability and career experiences of international graduates of MSc Public Health: a mixed methods study.

    Science.gov (United States)

    Buunaaisie, C; Manyara, A M; Annett, H; Bird, E L; Bray, I; Ige, J; Jones, M; Orme, J; Pilkington, P; Evans, D

    2018-05-08

    This article aims to describe the public health career experiences of international graduates of a Master of Science in Public Health (MSc PH) programme and to contribute to developing the evidence base on international public health workforce capacity development. A sequential mixed methods study was conducted between January 2017 and April 2017. Ninety-seven international graduates of one UK university's MSc PH programme were invited to take part in an online survey followed by semistructured interviews, for respondents who consented to be interviewed. We computed the descriptive statistics of the quantitative data obtained, and qualitative data were thematically analysed. The response rate was 48.5%. Most respondents (63%) were employed by various agencies within 1 year after graduation. Others (15%) were at different stages of doctor of philosophy studies. Respondents reported enhanced roles after graduation in areas such as public health policy analysis (74%); planning, implementation and evaluation of public health interventions (74%); leadership roles (72%); and research (70%). The common perceived skills that were relevant to the respondents' present jobs were critical analysis (87%), multidisciplinary thinking (86%), demonstrating public health leadership skills (84%) and research (77%). Almost all respondents (90%) were confident in conducting research. Respondents recommended the provision of longer public health placement opportunities, elective courses on project management and advanced statistics, and 'internationalisation' of the programme's curriculum. The study has revealed the relevance of higher education in public health in developing the career prospects and skills of graduates. International graduates of this MSc PH programme were satisfied with the relevance and impact of the skills they acquired during their studies. The outcomes of this study can be used for curriculum reformation. Employers' perspectives of the capabilities of these

  10. Uniaxial Compressive Strength and Fracture Mode of Lake Ice at Moderate Strain Rates Based on a Digital Speckle Correlation Method for Deformation Measurement

    Directory of Open Access Journals (Sweden)

    Jijian Lian

    2017-05-01

    Full Text Available Better understanding of the complex mechanical properties of ice is the foundation to predict the ice fail process and avoid potential ice threats. In the present study, uniaxial compressive strength and fracture mode of natural lake ice are investigated over moderate strain-rate range of 0.4–10 s−1 at −5 °C and −10 °C. The digital speckle correlation method (DSCM is used for deformation measurement through constructing artificial speckle on ice sample surface in advance, and two dynamic load cells are employed to measure the dynamic load for monitoring the equilibrium of two ends’ forces under high-speed loading. The relationships between uniaxial compressive strength and strain-rate, temperature, loading direction, and air porosity are investigated, and the fracture mode of ice at moderate rates is also discussed. The experimental results show that there exists a significant difference between true strain-rate and nominal strain-rate derived from actuator displacement under dynamic loading conditions. Over the employed strain-rate range, the dynamic uniaxial compressive strength of lake ice shows positive strain-rate sensitivity and decreases with increasing temperature. Ice obtains greater strength values when it is with lower air porosity and loaded vertically. The fracture mode of ice seems to be a combination of splitting failure and crushing failure.

  11. A wavelet ridge extraction method employing a novel cost function in two-dimensional wavelet transform profilometry

    Science.gov (United States)

    Wang, Jianhua; Yang, Yanxi

    2018-05-01

    We present a new wavelet ridge extraction method employing a novel cost function in two-dimensional wavelet transform profilometry (2-D WTP). First of all, the maximum value point is extracted from two-dimensional wavelet transform coefficient modulus, and the local extreme value points over 90% of maximum value are also obtained, they both constitute wavelet ridge candidates. Then, the gradient of rotate factor is introduced into the Abid's cost function, and the logarithmic Logistic model is used to adjust and improve the cost function weights so as to obtain more reasonable value estimation. At last, the dynamic programming method is used to accurately find the optimal wavelet ridge, and the wrapped phase can be obtained by extracting the phase at the ridge. Its advantage is that, the fringe pattern with low signal-to-noise ratio can be demodulated accurately, and its noise immunity will be better. Meanwhile, only one fringe pattern is needed to projected to measured object, so dynamic three-dimensional (3-D) measurement in harsh environment can be realized. Computer simulation and experimental results show that, for the fringe pattern with noise pollution, the 3-D surface recovery accuracy by the proposed algorithm is increased. In addition, the demodulation phase accuracy of Morlet, Fan and Cauchy mother wavelets are compared.

  12. Automatic Testing and Assessment of Neuroanatomy Using a Digital Brain Atlas: Method and Development of Computer- and Mobile-Based Applications

    Science.gov (United States)

    Nowinski, Wieslaw L.; Thirunavuukarasuu, Arumugam; Ananthasubramaniam, Anand; Chua, Beng Choon; Qian, Guoyu; Nowinska, Natalia G.; Marchenko, Yevgen; Volkau, Ihar

    2009-01-01

    Preparation of tests and student's assessment by the instructor are time consuming. We address these two tasks in neuroanatomy education by employing a digital media application with a three-dimensional (3D), interactive, fully segmented, and labeled brain atlas. The anatomical and vascular models in the atlas are linked to "Terminologia…

  13. Light-reflection random-target method for measurement of the modulation transfer function of a digital video-camera

    Science.gov (United States)

    Pospisil, J.; Jakubik, P.; Machala, L.

    2005-11-01

    This article reports the suggestion, realization and verification of the newly developed measuring means of the noiseless and locally shift-invariant modulation transfer function (MTF) of a digital video camera in a usual incoherent visible region of optical intensity, especially of its combined imaging, detection, sampling and digitizing steps which are influenced by the additive and spatially discrete photodetector, aliasing and quantization noises. Such means relates to the still camera automatic working regime and static two-dimensional spatially continuous light-reflection random target of white-noise property. The introduced theoretical reason for such a random-target method is also performed under exploitation of the proposed simulation model of the linear optical intensity response and possibility to express the resultant MTF by a normalized and smoothed rate of the ascertainable output and input power spectral densities. The random-target and resultant image-data were obtained and processed by means of a processing and evaluational PC with computation programs developed on the basis of MATLAB 6.5E The present examples of results and other obtained results of the performed measurements demonstrate the sufficient repeatability and acceptability of the described method for comparative evaluations of the performance of digital video cameras under various conditions.

  14. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for X-ray computed tomography (CT) test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice facilitates the interoperability of X-ray computed tomography (CT) imaging equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE test results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information object definitio...

  15. Optimal design methods for a digital human-computer interface based on human reliability in a nuclear power plant

    International Nuclear Information System (INIS)

    Jiang, Jianjun; Zhang, Li; Xie, Tian; Wu, Daqing; Li, Min; Wang, Yiqun; Peng, Yuyuan; Peng, Jie; Zhang, Mengjia; Li, Peiyao; Ma, Congmin; Wu, Xing

    2017-01-01

    Highlights: • A complete optimization process is established for digital human-computer interfaces of Npps. • A quick convergence search method is proposed. • The authors propose an affinity error probability mapping function to test human reliability. - Abstract: This is the second in a series of papers describing the optimal design method for a digital human-computer interface of nuclear power plant (Npp) from three different points based on human reliability. The purpose of this series is to explore different optimization methods from varying perspectives. This present paper mainly discusses the optimal design method for quantity of components of the same factor. In monitoring process, quantity of components has brought heavy burden to operators, thus, human errors are easily triggered. To solve the problem, the authors propose an optimization process, a quick convergence search method and an affinity error probability mapping function. Two balanceable parameter values of the affinity error probability function are obtained by experiments. The experimental results show that the affinity error probability mapping function about human-computer interface has very good sensitivity and stability, and that quick convergence search method for fuzzy segments divided by component quantity has better performance than general algorithm.

  16. Progress towards RF heated steady-state plasma operations on LHD by employing ICRF heating methods and improved divertor plates

    International Nuclear Information System (INIS)

    Kumazawa, R.; Mutoh, T.; Saito, K.

    2008-10-01

    A long pulse plasma discharge experiment was carried out using RF heating power in the Large Helical Device (LHD), a currentless magnetic confining system. Progress in long pulse operation is summarized since the 10th experimental campaign (2006). A scaling relation of the plasma duration time to the applied RF power has been derived from the experimental data so far collected. It indicates that there exists a critical divertor temperature and consequently a critical RF heating power P RFcrit =0.65 MW. The area on the graph of the duration time versus the RF heating power was extended over the scaling relation by replacing divertor plates with new ones with better heat conductivity. The cause of the plasma collapse at the end of the long pulse operation was found to be the penetration of metal impurities. Many thin flakes consisting of heavy metals and graphite in stratified layers were found on the divertor plates and it was thought that they were the cause of impurity metals penetrating into the plasma. In a simulation involving injecting a graphite-coated Fe pellet to the plasma it was found that 230 Eμm in the diameter of the Fe pellet sphere was the critical size which led the plasma to collapse. A mode-conversion heating method was examined in place of the minority ICRF heating which has been employed in almost all the long-pulse plasma discharges. It was found that this method was much better from the viewpoint of achieving uniformity of the plasma heat load to the divertors. It is expected that P RFcrit will be increased by using the mode-conversion heating method. (author)

  17. Method and practice on safety software verification and validation for digital reactor protection system

    International Nuclear Information System (INIS)

    Li Duo; Zhang Liangju; Feng Junting

    2010-01-01

    The key issue arising from digitalization of reactor protection system for Nuclear Power Plant (NPP) is in essence, how to carry out Verification and Validation (V and V), to demonstrate and confirm the software is reliable enough to perform reactor safety functions. Among others the most important activity of software V and V process is unit testing. This paper discusses the basic concepts on safety software V and V and the appropriate technique for software unit testing, focusing on such aspects as how to ensure test completeness, how to establish test platform, how to develop test cases and how to carry out unit testing. The technique discussed herein was successfully used in the work of unit testing on safety software of a digital reactor protection system. (author)

  18. Semi-automated digital measurement as the method of choice for beta cell mass analysis.

    Directory of Open Access Journals (Sweden)

    Violette Coppens

    Full Text Available Pancreas injury by partial duct ligation (PDL activates beta cell differentiation and proliferation in adult mouse pancreas but remains controversial regarding the anticipated increase in beta cell volume. Several reports unable to show beta cell volume augmentation in PDL pancreas used automated digital image analysis software. We hypothesized that fully automatic beta cell morphometry without manual micrograph artifact remediation introduces bias and therefore might be responsible for reported discrepancies and controversy. However, our present results prove that standard digital image processing with automatic thresholding is sufficiently robust albeit less sensitive and less adequate to demonstrate a significant increase in beta cell volume in PDL versus Sham-operated pancreas. We therefore conclude that other confounding factors such as quality of surgery, selection of samples based on relative abundance of the transcription factor Neurogenin 3 (Ngn3 and tissue processing give rise to inter-laboratory inconsistencies in beta cell volume quantification in PDL pancreas.

  19. Engaging Adolescents Through Participatory and Qualitative Research Methods to Develop a Digital Communication Intervention to Reduce Adolescent Obesity.

    Science.gov (United States)

    Livingood, William C; Monticalvo, David; Bernhardt, Jay M; Wells, Kelli T; Harris, Todd; Kee, Kadra; Hayes, Johnathan; George, Donald; Woodhouse, Lynn D

    2017-08-01

    The complexity of the childhood obesity epidemic requires the application of community-based participatory research (CBPR) in a manner that can transcend multiple communities of stakeholders, including youth, the broader community, and the community of health care providers. To (a) describe participatory processes for engaging youth within context of CBPR and broader community, (b) share youth-engaged research findings related to the use of digital communication and implications for adolescent obesity intervention research, and (c) describe and discuss lessons learned from participatory approaches. CBPR principles and qualitative methods were synergistically applied in a predominantly African American part of the city that experiences major obesity-related issues. A Youth Research Advisory Board was developed to deeply engage youth in research that was integrated with other community-based efforts, including an academic-community partnership, a city-wide obesity coalition, and a primary care practice research network. Volunteers from the youth board were trained to apply qualitative methods, including facilitating focus group interviews and analyzing and interpreting data with the goal of informing a primary care provider-based obesity reduction intervention. The primary results of these efforts were the development of critical insights about adolescent use of digital communication and the potential importance of messaging, mobile and computer apps, gaming, wearable technology, and rapid changes in youth communication and use of digital technology in developing adolescent nutrition and physical activity health promotion. The youth led work helped identify key elements for a digital communication intervention that was sensitive and responsive to urban youth. Many valuable lessons were also learned from 3 years of partnerships and collaborations, providing important insights on applying CBPR with minority youth populations.

  20. A digital future for the history of psychology?

    Science.gov (United States)

    Green, Christopher D

    2016-08-01

    This article discusses the role that digital approaches to the history of psychology are likely to play in the near future. A tentative hierarchy of digital methods is proposed. A few examples are briefly described: a digital repository, a simple visualization using ready-made online database and tools, and more complex visualizations requiring the assembly of the database and, possibly, the analytic tools by the researcher. The relationship of digital history to the old "New Economic History" (Cliometrics) is considered. The question of whether digital history and traditional history need be at odds or, instead, might complement each other is woven throughout. The rapidly expanding territory of digital humanistic research outside of psychology is briefly discussed. Finally, the challenging current employment trends in history and the humanities more broadly are considered, along with the role that digital skills might play in mitigating those factors for prospective academic workers. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  1. Judges Awareness, Understanding, and Application of Digital Evidence

    Directory of Open Access Journals (Sweden)

    Gary C Kessler

    2011-03-01

    Full Text Available As digital evidence grows in both volume and importance in criminal and civil courts, judges need to fairly and justly evaluate the merits of the offered evidence. To do so, judges need a general understanding of the underlying technologies and applications from which digital evidence is derived. Due to the relative newness of the computer forensics field, there have been few studies on the use of digital forensic evidence and none about judges’ relationship with digital evidence.This paper describes a recent study, using grounded theory methods, into judges’ awareness, knowledge, and perceptions of digital evidence. This study is the first in the U.S. to examine judges and digital forensics, thus opening up a new avenue of research. It is the second time that grounded theory has been employed in a published digital forensics study, demonstrating the applicability of that methodology to this discipline.

  2. Method for measuring the focal spot size of an x-ray tube using a coded aperture mask and a digital detector.

    Science.gov (United States)

    Russo, Paolo; Mettivier, Giovanni

    2011-04-01

    The goal of this study is to evaluate a new method based on a coded aperture mask combined with a digital x-ray imaging detector for measurements of the focal spot sizes of diagnostic x-ray tubes. Common techniques for focal spot size measurements employ a pinhole camera, a slit camera, or a star resolution pattern. The coded aperture mask is a radiation collimator consisting of a large number of apertures disposed on a predetermined grid in an array, through which the radiation source is imaged onto a digital x-ray detector. The method of the coded mask camera allows one to obtain a one-shot accurate and direct measurement of the two dimensions of the focal spot (like that for a pinhole camera) but at a low tube loading (like that for a slit camera). A large number of small apertures in the coded mask operate as a "multipinhole" with greater efficiency than a single pinhole, but keeping the resolution of a single pinhole. X-ray images result from the multiplexed output on the detector image plane of such a multiple aperture array, and the image of the source is digitally reconstructed with a deconvolution algorithm. Images of the focal spot of a laboratory x-ray tube (W anode: 35-80 kVp; focal spot size of 0.04 mm) were acquired at different geometrical magnifications with two different types of digital detector (a photon counting hybrid silicon pixel detector with 0.055 mm pitch and a flat panel CMOS digital detector with 0.05 mm pitch) using a high resolution coded mask (type no-two-holes-touching modified uniformly redundant array) with 480 0.07 mm apertures, designed for imaging at energies below 35 keV. Measurements with a slit camera were performed for comparison. A test with a pinhole camera and with the coded mask on a computed radiography mammography unit with 0.3 mm focal spot was also carried out. The full width at half maximum focal spot sizes were obtained from the line profiles of the decoded images, showing a focal spot of 0.120 mm x 0.105 mm at 35

  3. Extraction of fish body oil from Sardinella longiceps by employing direct steaming method and its quantitative and qualitative assessment

    Directory of Open Access Journals (Sweden)

    Moorthy Pravinkumar

    2015-12-01

    Full Text Available Objective: To analyze the quantitative and qualitative properties of the extracted fish oil from Sardinella longiceps (S. longiceps. Methods: Four size groups of S. longiceps were examined for the extraction of fish oil based on length. The size groups included Group I (size range of 7.1–10.0 cm, Group II (size range of 10.1–13.0 cm, Group III (size range of 13.1–16.0 cm and Group IV (size range of 16.1– 19.0 cm. Fish oil was extracted from the tissues of S. longiceps by direct steaming method. The oil was then subjected to the determination of specific gravity, refractive index, moisture content, free fatty acids, iodine value, peroxide value, saponification value and observation of colour. Results: The four groups showed different yield of fish oil that Group IV recorded the highest values of (165.00 ± 1.00 mL/kg followed by Group III [(145.66 ± 1.15 mL/kg] and Group II [(129.33 ± 0.58 mL/kg], whereas Group I recorded the lowest values of (78.33 ± 0.58 mL/ kg in monsoon season, and the average yield was (180.0 ± 4.9 mL/kg fish tissues. These analytical values of the crude oil were well within the acceptable standard values for both fresh and stocked samples. Conclusions: The information generated in the present study pertaining to the quantitative and qualitative analysis of fish oil will serve as a reference baseline for entrepreneurs and industrialists in future for the successful commercial production of fish oil by employing oil sardines.

  4. Combining garden therapy and supported employment - a method for preparing women on long-term sick leave for working life.

    Science.gov (United States)

    Lidén, Eva; Alstersjö, Karin; Gurné, Frida L; Fransson, Sandra; Bergbom, Ingegerd

    2016-06-01

    Women are overrepresented among the group people suffering from long-term illness. In addition to their illness, suffering long-term sick leave leads to economical restraints as well social distress. There are gaps in our understanding of the challenges these women face. There is also lack of knowledge about how these challenges can be effectively addressed in rehabilitation. This deficiency is problematic from an ethical, justice and a caring perspective. In this study, changes in health-related quality of life (HRQoL) among women on long-term sick leave were investigated during and after participating in a rehabilitation programme combining two validated methods, Garden Therapy and Supported Employment (SE). The study also discusses difficulties in realising research related to vulnerable under-privileged people. From a population of 329 women who had reported their interest to participate, 245 were randomised to the programme. Of these 144 accepted participation in the research project and of these 123 women accepted to answer the SF-36 questionnaire. The participants were between 21 and 62 years with poor physical and mental health. They had received public financial support from 10 years. The SF-36 measurement was carried out at baseline, after completion of Garden Therapy and after completion of SE. The results are based on data of respondents who participated at all the three occasions (n = 52). When comparing HRQoL baseline with the following occasions, the participants' General Health (GH), Vitality (VT), Social Functioning (SF) and mental health had improved significantly. The Four Leaf Clover (FLC) programme could be an appropriate method for reducing socially induced suffering. However, to conduct intervention studies where vulnerable persons are involved, it is off vital importance to consider whether the participants have the strength to complete the intervention. © 2015 Nordic College of Caring Science.

  5. Analysis 'in vivo' of the employ of the Er:YAG laser and conventional method to remove carious tissue

    International Nuclear Information System (INIS)

    Ribeiro, Rafael Cardoso

    2002-01-01

    The aim of this study was to evaluate the removal of carious tissue employing the use of Er:YAG laser in comparison with the conventional burr rotary instrument. The wavelength of this laser is 2,64 μm and have a good absorption by the water and hydroxyapatite present in dental hard tissue. For this purpose were selected 24 molar teeth with occlusal carious, which were divided in random in two groups. For enamel, the laser energy used was in the interval from 250 mJ to 400 mJ, and the frequency range from 2 Hz to 4 Hz; for the dentine the energy laser range was from 150 mJ to 200 mJ and the laser frequency was in the range from 2 Hz to 6 Hz. For the evaluation of the results was used a questionaire to critical evaluation of the professional and another one to evaluation of the patient. The results have shown that the Er:YAG laser is able to remove carious enamel and dentin, without cause crunch or fracture and the irradiated surface was creasy. The patients reported greatest comfort when the cavity preparation was done with the Er:YAG laser than the conventional burr and all the patients treated reported prefer to future treatments the use of the Er:YAG laser. In conclusion, for the critical evaluation of the professional the treatment with the Er:YAG laser is a safe and effective method, and for the critical evaluation of the patient the treatment is one alternative more comfortable than the conventional method to remove caries. (author)

  6. Digit-color synaesthesia only enhances memory for colors in a specific context: A new method of duration thresholds to measure serial recall.

    Science.gov (United States)

    Teichmann, A Lina; Nieuwenstein, Mark R; Rich, Anina N

    2017-08-01

    For digit-color synaesthetes, digits elicit vivid experiences of color that are highly consistent for each individual. The conscious experience of synaesthesia is typically unidirectional: Digits evoke colors but not vice versa. There is an ongoing debate about whether synaesthetes have a memory advantage over non-synaesthetes. One key question in this debate is whether synaesthetes have a general superiority or whether any benefit is specific to a certain type of material. Here, we focus on immediate serial recall and ask digit-color synaesthetes and controls to memorize digit and color sequences. We developed a sensitive staircase method manipulating presentation duration to measure participants' serial recall of both overlearned and novel sequences. Our results show that synaesthetes can activate digit information to enhance serial memory for color sequences. When color sequences corresponded to ascending or descending digit sequences, synaesthetes encoded these sequences at a faster rate than their non-synaesthetes counterparts and faster than non-structured color sequences. However, encoding color sequences is approximately 200 ms slower than encoding digit sequences directly, independent of group and condition, which shows that the translation process is time consuming. These results suggest memory advantages in synaesthesia require a modified dual-coding account, in which secondary (synaesthetically linked) information is useful only if it is more memorable than the primary information to be recalled. Our study further shows that duration thresholds are a sensitive method to measure subtle differences in serial recall performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Qualitative Evaluation of Digital Hand X-rays is Not a Reliable Method to Assess Bone Mineral Density

    Directory of Open Access Journals (Sweden)

    AndrewJ. Miller

    2017-01-01

    Full Text Available Object: The gold standard for evaluating bone mineral density is dual energy x-ray absorptiometry (DEXA.  Prior studies have shown poor reliability using analog wrist X-rays in diagnosing osteoporosis. Our goal was to investigate if there was improved diagnostic value to visual assessment of digital hand X-rays in osteoporosis screening. We hypothesized that similar to analog counterparts, digital hand X-rays have poor correlation and reliability in determining bone mineral density (BMD relative to DEXA.Methods: We prospectively evaluated female patients older than 65 years who presented to our hand clinic with digital hand and wrist X-rays as part of their evaluation over six months. Patients who had a fracture and were without DEXA scans within the past two years were excluded. Five fellowship-trained hand surgeons, blinded to DEXA T-scores, evaluated the x-rays over two assessments separated by four weeks and classified them as osteoporotic, osteopenic, or normal BMD.  Accuracy relative to DEXA T-score, interobserver and intraobserver rates were calculated.Results: Thirty four patients met the inclusion criteria and a total of 340 x-rays reviews were performed.  The assessments were correct in 169 cases (49% as compared to the DEXA T-scores. A mean weighted kappa coefficient of agreement between observers was 0.29 (range 0.02-0.41 reflecting a fair agreement. The first and second assessment for all five physicians was 0.46 (range 0.19-0.78 reflecting a moderate agreement.  Grouping osteoporosis and osteopenia together compared to normal, the accuracy, interobserver and intraobserver rates increased to 63%, 0.42 and 0.54 respectively.Conclusion: Abnormally low BMD is a common occurrence in patients treated for upper extremity disorders. There is poor accuracy relative to DEXA scan and only fair agreement in diagnosing osteoporosis using visual assessments of digital x-rays.

  8. 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.

  9. 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.

  10. Cultural Heritage Digitalization on Traditional Sundanese Music Instrument Using Augmented Reality Markerless Marker Method

    Directory of Open Access Journals (Sweden)

    Budi Arifitama

    2017-07-01

    Full Text Available Research into cultural heritage which implements augmented reality technology is limited. Most recent research on cultural heritage are limited on storing data and information in the form of databases, this creates a disadvantage for people who wants to see and feel at the same moment on actual cultural heritage objects. This paper, proposes a solution which could merge the existing cultural object with people using augmented reality technology. This technology would preserve traditional instrument in the form of 3D object which can be digitally protected. The result showed that the use of augmented reality on preserving cultural heritage would benefit people who try to protect their culture.

  11. The method for objective evaluation of the intensity of radial bone lesions in rheumatoid arthritis using digital image analysis

    International Nuclear Information System (INIS)

    Zielinski, K.W.; Krekora, K.

    2004-01-01

    The semiquantitative methods used in everyday diagnostic practice for scoring the intensity of bone lesions in rheumatoid arthritis are susceptible to a subjective error. The paper describes the original algorithm for an image analysis as a method for quantitative and objective evaluation of the intensity of radiological lesions in rheumatoid arthritis. 75 plain radiograms of the hand of patients diagnosed with rheumatoid arthritis, in various stages of bone pathology, were evaluated. The analysis focused on the signs of pathological rebuilding of the affected bone, especially in the distal epiphysis of the radial bone. The plain radiograms of the hand were digitally analysed based on the modified method, formerly used for quantitative assessment of bone trabeculation. The method allowed us to objectively verify various scoring systems of radiograms widely used in rheumatological diagnosis. (author)

  12. Method for the calculation of volumetric fraction of retained austenite through the software for analysis of digital images

    International Nuclear Information System (INIS)

    Lombardo, S.; Costa, F.H.; Hashimoto, T.M.; Pereira, M.S.; Abdalla, A.J.

    2010-01-01

    In order to calculate the volume fraction of the retained austenite in aeronautic multiphase steels, it was used a digital analysis software for image processing. The materials studied were steels AISI 43XX with carbon content between 30, 40 and 50%, heat treated by conventional quenching and isothermal cooling in bainitic and intercritical region, characterized by optical microscopy, etching by reagent Sodium Metabisulfite (10%) for 30 seconds, with forced drying. The results were compared with the methods of X-Ray Diffraction and Magnetic Saturation through photomicrographs, showing that with this technic it is possible to quantify the percentage of retained austenite in the martensitic matrix, in the different types of steels. (author)

  13. Cavity digital control testing system by Simulink step operation method for TESLA linear accelerator and free electron laser

    Science.gov (United States)

    Czarski, Tomasz; Romaniuk, Ryszard S.; Pozniak, Krzysztof T.; Simrock, Stefan

    2004-07-01

    The cavity control system for the TESLA -- TeV-Energy Superconducting Linear Accelerator project is initially introduced in this paper. The FPGA -- Field Programmable Gate Array technology has been implemented for digital controller stabilizing cavity field gradient. The cavity SIMULINK model has been applied to test the hardware controller. The step operation method has been developed for testing the FPGA device coupled to the SIMULINK model of the analog real plant. The FPGA signal processing has been verified according to the required algorithm of the reference MATLAB controller. Some experimental results have been presented for different cavity operational conditions.

  14. An Internet-Based Course And The Application Of Employment-Based Methods In Civil Engineering Projects

    NARCIS (Netherlands)

    de Boer, S.J.; van de Vis, Dimitri; van de Vis, Dimitri; Mosch, Lars P.J.; Taylor Perkins, F.

    2001-01-01

    The paper addresses the question of how educational activities in civil engineering in the Netherlands can contribute to the application of employment-based programs in developing countries. National policy makers and international donor representatives acknowledge the various advantages of

  15. Features of method of employments on aerobics with the use of exercises of sporting orientation. [Osobennosti metodiki zaniatij po aerobike s ispol'zovaniem uprazhnenij sportivnoj napravlennosti

    Directory of Open Access Journals (Sweden)

    Lulina N.V.

    2011-11-01

    Full Text Available The features of method of leadthrough of employments are considered on aerobics. 24 girls of the first course took part in an experiment. Directions are offered perfection of outside the time limit forms of employments. A basic orientation of employments is a capture from the different types of sport and increase of level of physical preparedness of girls motive actions. Is proposed method of employments on aerobics with the use of imitation exercises from the different types of sport. It is rotined that with imaginary objects in hands it is possible to execute different exercises: javelin-throwing or kernel, throws of ball etc. It is set that during a slow imitation individuality of loading is regulated the volitional capabilities of man. In this case protective reflexes do not allow to overstrain a muscle.

  16. Development and Validation of HPLC-DAD and UHPLC-DAD Methods for the Simultaneous Determination of Guanylhydrazone Derivatives Employing a Factorial Design.

    Science.gov (United States)

    Azevedo de Brito, Wanessa; Gomes Dantas, Monique; Andrade Nogueira, Fernando Henrique; Ferreira da Silva-Júnior, Edeildo; Xavier de Araújo-Júnior, João; Aquino, Thiago Mendonça de; Adélia Nogueira Ribeiro, Êurica; da Silva Solon, Lilian Grace; Soares Aragão, Cícero Flávio; Barreto Gomes, Ana Paula

    2017-08-30

    Guanylhydrazones are molecules with great pharmacological potential in various therapeutic areas, including antitumoral activity. Factorial design is an excellent tool in the optimization of a chromatographic method, because it is possible quickly change factors such as temperature, mobile phase composition, mobile phase pH, column length, among others to establish the optimal conditions of analysis. The aim of the present work was to develop and validate a HPLC and UHPLC methods for the simultaneous determination of guanylhydrazones with anticancer activity employing experimental design. Precise, exact, linear and robust HPLC and UHPLC methods were developed and validated for the simultaneous quantification of the guanylhydrazones LQM10, LQM14, and LQM17. The UHPLC method was more economic, with a four times less solvent consumption, and 20 times less injection volume, what allowed better column performance. Comparing the empirical approach employed in the HPLC method development to the DoE approach employed in the UHPLC method development, we can conclude that the factorial design made the method development faster, more practical and rational. This resulted in methods that can be employed in the analysis, evaluation and quality control of these new synthetic guanylhydrazones.

  17. Validation of Shape Context Based Image Registration Method Using Digital Image Correlation Measurement on a Rat Stomach

    DEFF Research Database (Denmark)

    Liao, Donghua; Wang, P; Zhao, Jingbo

    2014-01-01

    Recently we developed analysis for 3D visceral organ deformation by combining the shape context (SC) method with a full-field strain (strain distribution on a whole 3D surface) analysis for calculating distension-induced rat stomach deformation. The surface deformation detected by the SC method...... needs to be further verified by using a feature tracking measurement. Hence, the aim of this study was to verify the SC method-based calculation by using digital image correlation (DIC) measurement on a rat stomach. The rat stomach exposed to distension pressures 0.0, 0.2, 0.4, and 0.6 kPa were studied...... and the SC calculated correspondence surface was compared. Compared with DIC measurement, the SC calculated surface had errors from 5% to 23% at pressures from 0.2 to 0.6 kPa with different surface sample counts between the reference surface and the target surface. This indicates good qualitative...

  18. Field test comparison of an autocorrelation technique for determining grain size using a digital 'beachball' camera versus traditional methods

    Science.gov (United States)

    Barnard, P.L.; Rubin, D.M.; Harney, J.; Mustain, N.

    2007-01-01

    This extensive field test of an autocorrelation technique for determining grain size from digital images was conducted using a digital bed-sediment camera, or 'beachball' camera. Using 205 sediment samples and >1200 images from a variety of beaches on the west coast of the US, grain size ranging from sand to granules was measured from field samples using both the autocorrelation technique developed by Rubin [Rubin, D.M., 2004. A simple autocorrelation algorithm for determining grain size from digital images of sediment. Journal of Sedimentary Research, 74(1): 160-165.] and traditional methods (i.e. settling tube analysis, sieving, and point counts). To test the accuracy of the digital-image grain size algorithm, we compared results with manual point counts of an extensive image data set in the Santa Barbara littoral cell. Grain sizes calculated using the autocorrelation algorithm were highly correlated with the point counts of the same images (r2 = 0.93; n = 79) and had an error of only 1%. Comparisons of calculated grain sizes and grain sizes measured from grab samples demonstrated that the autocorrelation technique works well on high-energy dissipative beaches with well-sorted sediment such as in the Pacific Northwest (r2 ??? 0.92; n = 115). On less dissipative, more poorly sorted beaches such as Ocean Beach in San Francisco, results were not as good (r2 ??? 0.70; n = 67; within 3% accuracy). Because the algorithm works well compared with point counts of the same image, the poorer correlation with grab samples must be a result of actual spatial and vertical variability of sediment in the field; closer agreement between grain size in the images and grain size of grab samples can be achieved by increasing the sampling volume of the images (taking more images, distributed over a volume comparable to that of a grab sample). In all field tests the autocorrelation method was able to predict the mean and median grain size with ???96% accuracy, which is more than

  19. Higuchi’s Method applied to detection of changes in timbre of digital sound synthesis of string instruments with the functional transformation method

    Science.gov (United States)

    Kanjanapen, Manorth; Kunsombat, Cherdsak; Chiangga, Surasak

    2017-09-01

    The functional transformation method (FTM) is a powerful tool for detailed investigation of digital sound synthesis by the physical modeling method, the resulting sound or measured vibrational characteristics at discretized points on real instruments directly solves the underlying physical effect of partial differential equation (PDE). In this paper, we present the Higuchi’s method to examine the difference between the timbre of tone and estimate fractal dimension of musical signals which contains information about their geometrical structure that synthesizes by FTM. With the Higuchi’s method we obtain the whole process is not complicated, fast processing, with the ease of analysis without expertise in the physics or virtuoso musicians and the easiest way for the common people can judge that sounds similarly presented.

  20. [Method for evaluating the positional accuracy of a six-degrees-of-freedom radiotherapy couch using high definition digital cameras].

    Science.gov (United States)

    Takemura, Akihiro; Ueda, Shinichi; Noto, Kimiya; Kurata, Yuichi; Shoji, Saori

    2011-01-01

    In this study, we proposed and evaluated a positional accuracy assessment method with two high-resolution digital cameras for add-on six-degrees-of-freedom radiotherapy (6D) couches. Two high resolution digital cameras (D5000, Nikon Co.) were used in this accuracy assessment method. These cameras were placed on two orthogonal axes of a linear accelerator (LINAC) coordinate system and focused on the isocenter of the LINAC. Pictures of a needle that was fixed on the 6D couch were taken by the cameras during couch motions of translation and rotation of each axis. The coordinates of the needle in the pictures were obtained using manual measurement, and the coordinate error of the needle was calculated. The accuracy of a HexaPOD evo (Elekta AB, Sweden) was evaluated using this method. All of the mean values of the X, Y, and Z coordinate errors in the translation tests were within ±0.1 mm. However, the standard deviation of the Z coordinate errors in the Z translation test was 0.24 mm, which is higher than the others. In the X rotation test, we found that the X coordinate of the rotational origin of the 6D couch was shifted. We proposed an accuracy assessment method for a 6D couch. The method was able to evaluate the accuracy of the motion of only the 6D couch and revealed the deviation of the origin of the couch rotation. This accuracy assessment method is effective for evaluating add-on 6D couch positioning.

  1. Rethinking Communication: The Role of Digital Media from Bagozzi and Phillips’ Method

    Directory of Open Access Journals (Sweden)

    Maryalejandra Montiel

    2009-08-01

    Full Text Available The purpose of this paper is to make use of the holistic constructivism, proposed by Bagozzi & Phillips (1982, to provide structure to a methodological – theoretical body that would sustain the research named: “ Communication and Democracy: the role of cybermedia in the building of citizenship”. Its content encloses concepts about communication, digital media and democratization. Finally it elaborates a theoretical network where the theoretical, derived and empirical concepts exposed, as well as the relationships among them. The idea is to approach to accelerating and drastic changes of this 21st century, in view of the growing technological advances and the presence of global processes. The epicenter of these realities is the man and the construction of his world.

  2. A customizable multi-channel loudness compensation method based on WDRC for digital hearing aids

    Science.gov (United States)

    Hu, Jiebin; Wang, Mingjiang; Ma, Min

    2017-08-01

    Loudness compensation is the most significant signal processing algorithm in digital hearing aids at present. An algorithm of multi-channel loudness compensation for embedded system has been put forward in this paper. The number of channels is customizable in this algorithm. The algorithm can set different number and different width of channels for each patient based on frequency domain wide dynamic range compression. First, according to the requirement of patient to divide the frequency domain into multiple unequal frequency bands. And then calculate the gain of each channel according to the input-output curve of sound pressure level. Finally, the time-domain impulse response of gain is computed from Mel filter banks. It is used in conjunction with speech enhancement processing in hearing aids. Simulation results show that the algorithm can effectively enhance the loudness for different frequencies.

  3. Measurement methods updating for tandem-generator EGP-10K with using of digital technology

    Directory of Open Access Journals (Sweden)

    I. P. Dryapachenko

    2012-06-01

    Full Text Available During the last 10 years a number of fundamental and applied research at the electrostatic charge-exchange accelerator EGP-10K INR NAS with the proton and deuteron beams were performed. Currently, the program of optimization of the accelerator parameters, especially – the energy and intensity of the beam has being implemented. At the same time the possibilities of the transport and use of the accelerator beam through the creation of additional sections of beam tube and reaction chambers, as well as the possibilities of the measurements and data processing particularly, in the reconstructed measuring center of the previous single-stage accelerator EG-5, were improved. This paper presents the results of modernization of infrastructure of the experimental studies with the beams of the accelerator EGP-10K using the latest equipment and modern digital technique for beam diagnostics, registration of the reaction products and visualization of the obtained data.

  4. Validation of a method for measuring the volumetric breast density from digital mammograms

    International Nuclear Information System (INIS)

    Alonzo-Proulx, O; Shen, S Z; Yaffe, M J; Packard, N; Boone, J M; Al-Mayah, A; Brock, K K

    2010-01-01

    The purpose of this study was to evaluate the performance of an algorithm used to measure the volumetric breast density (VBD) from digital mammograms. The algorithm is based on the calibration of the detector signal versus the thickness and composition of breast-equivalent phantoms. The baseline error in the density from the algorithm was found to be 1.25 ± 2.3% VBD units (PVBD) when tested against a set of calibration phantoms, of thicknesses 3-8 cm, with compositions equivalent to fibroglandular content (breast density) between 0% and 100% and under x-ray beams between 26 kVp and 32 kVp with a Rh/Rh anode/filter. The algorithm was also tested against images from a dedicated breast computed tomography (CT) scanner acquired on 26 volunteers. The CT images were segmented into regions representing adipose, fibroglandular and skin tissues, and then deformed using a finite-element algorithm to simulate the effects of compression in mammography. The mean volume, VBD and thickness of the compressed breast for these deformed images were respectively 558 cm 3 , 23.6% and 62 mm. The displaced CT images were then used to generate simulated digital mammograms, considering the effects of the polychromatic x-ray spectrum, the primary and scattered energy transmitted through the breast, the anti-scatter grid and the detector efficiency. The simulated mammograms were analyzed with the VBD algorithm and compared with the deformed CT volumes. With the Rh/Rh anode filter, the root mean square difference between the VBD from CT and from the algorithm was 2.6 PVBD, and a linear regression between the two gave a slope of 0.992 with an intercept of -1.4 PVBD and a correlation with R 2 = 0.963. The results with the Mo/Mo and Mo/Rh anode/filter were similar.

  5. Validation of a method for measuring the volumetric breast density from digital mammograms

    Energy Technology Data Exchange (ETDEWEB)

    Alonzo-Proulx, O; Shen, S Z; Yaffe, M J [Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Packard, N; Boone, J M [UC Davis Medical Center, University of California-Davis, Sacramento, CA 95817 (United States); Al-Mayah, A; Brock, K K, E-mail: oliviera@sri.utoronto.c [University Health Network, University of Toronto, Toronto, Ontario M5G 2M9 (Canada)

    2010-06-07

    The purpose of this study was to evaluate the performance of an algorithm used to measure the volumetric breast density (VBD) from digital mammograms. The algorithm is based on the calibration of the detector signal versus the thickness and composition of breast-equivalent phantoms. The baseline error in the density from the algorithm was found to be 1.25 {+-} 2.3% VBD units (PVBD) when tested against a set of calibration phantoms, of thicknesses 3-8 cm, with compositions equivalent to fibroglandular content (breast density) between 0% and 100% and under x-ray beams between 26 kVp and 32 kVp with a Rh/Rh anode/filter. The algorithm was also tested against images from a dedicated breast computed tomography (CT) scanner acquired on 26 volunteers. The CT images were segmented into regions representing adipose, fibroglandular and skin tissues, and then deformed using a finite-element algorithm to simulate the effects of compression in mammography. The mean volume, VBD and thickness of the compressed breast for these deformed images were respectively 558 cm{sup 3}, 23.6% and 62 mm. The displaced CT images were then used to generate simulated digital mammograms, considering the effects of the polychromatic x-ray spectrum, the primary and scattered energy transmitted through the breast, the anti-scatter grid and the detector efficiency. The simulated mammograms were analyzed with the VBD algorithm and compared with the deformed CT volumes. With the Rh/Rh anode filter, the root mean square difference between the VBD from CT and from the algorithm was 2.6 PVBD, and a linear regression between the two gave a slope of 0.992 with an intercept of -1.4 PVBD and a correlation with R{sup 2} = 0.963. The results with the Mo/Mo and Mo/Rh anode/filter were similar.

  6. 3D documenatation of the petalaindera: digital heritage preservation methods using 3D laser scanner and photogrammetry

    Science.gov (United States)

    Sharif, Harlina Md; Hazumi, Hazman; Hafizuddin Meli, Rafiq

    2018-01-01

    3D imaging technologies have undergone massive revolution in recent years. Despite this rapid development, documentation of 3D cultural assets in Malaysia is still very much reliant upon conventional techniques such as measured drawings and manual photogrammetry. There is very little progress towards exploring new methods or advanced technologies to convert 3D cultural assets into 3D visual representation and visualization models that are easily accessible for information sharing. In recent years, however, the advent of computer vision (CV) algorithms make it possible to reconstruct 3D geometry of objects by using image sequences from digital cameras, which are then processed by web services and freeware applications. This paper presents a completed stage of an exploratory study that investigates the potentials of using CV automated image-based open-source software and web services to reconstruct and replicate cultural assets. By selecting an intricate wooden boat, Petalaindera, this study attempts to evaluate the efficiency of CV systems and compare it with the application of 3D laser scanning, which is known for its accuracy, efficiency and high cost. The final aim of this study is to compare the visual accuracy of 3D models generated by CV system, and 3D models produced by 3D scanning and manual photogrammetry for an intricate subject such as the Petalaindera. The final objective is to explore cost-effective methods that could provide fundamental guidelines on the best practice approach for digital heritage in Malaysia.

  7. Focus measure method based on the modulus of the gradient of the color planes for digital microscopy

    Science.gov (United States)

    Hurtado-Pérez, Román; Toxqui-Quitl, Carina; Padilla-Vivanco, Alfonso; Aguilar-Valdez, J. Félix; Ortega-Mendoza, Gabriel

    2018-02-01

    The modulus of the gradient of the color planes (MGC) is implemented to transform multichannel information to a grayscale image. This digital technique is used in two applications: (a) focus measurements during autofocusing (AF) process and (b) extending the depth of field (EDoF) by means of multifocus image fusion. In the first case, the MGC procedure is based on an edge detection technique and is implemented in over 15 focus metrics that are typically handled in digital microscopy. The MGC approach is tested on color images of histological sections for the selection of in-focus images. An appealing attribute of all the AF metrics working in the MGC space is their monotonic behavior even up to a magnification of 100×. An advantage of the MGC method is its computational simplicity and inherent parallelism. In the second application, a multifocus image fusion algorithm based on the MGC approach has been implemented on graphics processing units (GPUs). The resulting fused images are evaluated using a nonreference image quality metric. The proposed fusion method reveals a high-quality image independently of faulty illumination during the image acquisition. Finally, the three-dimensional visualization of the in-focus image is shown.

  8. Evaluation of a Digital Consultation and Self-Care Advice Tool in Primary Care: A Multi-Methods Study

    Directory of Open Access Journals (Sweden)

    Julie Cowie

    2018-05-01

    Full Text Available Digital services are often regarded as a solution to the growing demands on primary care services. Provision of a tool offering advice to support self-management as well as the ability to digitally consult with a General Practitioner (GP has the potential to alleviate some of the pressure on primary care. This paper reports on a Phase II, 6-month evaluation of eConsult, a web-based triage and consultation system that was piloted across 11 GP practices across Scotland. Through a multi-method approach the evaluation explored eConsult use across practices, exposing both barriers and facilitators to its adoption. Findings suggest that expectations that eConsult would offer an additional and alternative method of accessing GP services were largely met. However, there is less certainty that it has fulfilled expectations of promoting self-help. In addition, low uptake meant that evaluation of current effectiveness was difficult for practices to quantify. The presence of an eConsult champion(s within the practice was seen to be a significant factor in ensuring successful integration of the tool. A lack of patient and staff engagement, insufficient support and lack of protocols around processes were seen as barriers to its success.

  9. Age estimation by modified Demirjian's method (2004) and its applicability in Tibetan young adults: A digital panoramic study.

    Science.gov (United States)

    Bijjaragi, Shobha C; Sangle, Varsha A; Saraswathi, F K; Patil, Veerendra S; Ashwini Rani, S R; Bapure, Sunil K

    2015-01-01

    Estimation of the age is a procedure adopted by anthropologists, archeologists and forensic scientists. Different methods have been undertaken. However none of them meet the standards as Demirjian's method since 1973. Various researchers have applied this method, in both original and modified form (Chaillet and Demirjian in 2004) in different ethnic groups and the results obtained were not satisfactory. To determine the applicability and accuracy of modified Demirjian's method of dental age estimation (AE) in 8-18 year old Tibetan young adults to evaluate the interrelationship between dental and chronological age and the reliability between intra- and inter observer relationship. Clinical setting and computerized design. A total of 300 Tibetan young adults with an age range from 8 to 18 years were recruited in the study. Digital panoramic radiographs (DPRs) were evaluated as per the modified Demirjian's method (2004). Pearson correlation, paired t-test, linear regression analysis. Inter -and intraobserver reliability revealed a strong agreement. A positive and strong association was found between chronological age and estimated dental age (r = 0.839) with P < 0.01. Modified Demirjian method (2004) overestimated the age by 0.04 years (2.04 months)in Tibetan young adults. Results suggest that, the modified Demirjian method of AE is not suitable for Tibetan young adults. Further studies: With larger sample size and comparision with different methods of AE in a given population would be an interesting area for future research.

  10. PA12 Is digital storytelling ka pai for new zealand māori? using digital storytelling as a method to explore whānau end of life caregiving experiences: a pilot study.

    Science.gov (United States)

    Williams, Lisa; Moeke-Maxwell, Tess; Kothari, Shuchi; Pearson, Sarina; Gott, Merryn; Black, Stella; Frey, Rosemary; Wharemate, Rawiri; Hansen, Whio

    2015-04-01

    Māori regard stories as a preferred method for imparting knowledge through waiata (song), moteatea (poetry), kauwhau (moralistic tale), pakiwaitara (story) and purakau (myths). Storytelling is also an expression of tinorangatiratanga (self-determination); Māori have the right to manage their knowledge, which includes embodiment in forms transcending typical western formulations. Digital storytelling is a process by which 'ordinary people' create short autobiographical videos. It has found application in numerous disciplines including public health and has been used to articulatethe experiences of those often excluded from knowledge production. To explore the use of digital storytelling as a research method for learning about whānau (family) experiences providing end of life care for kaumātua (older people). Eight Māori and their nominated co-creators attended a three-day digital story telling workshop led by co-researchers Shuchi Kothari and Sarina Pearson. They were guided in the creation of first-person digital stories about caring for kaumātua. The videos were shared at a group screening, and participants completed questionnaires about the workshop and their videos. A Kaupapa Māori narrative analysis was applied to their stories to gain new perspectives on Māori end of life caregiving practices. (Kaupapa Maori research privileges Maori worldviews and indigenous knowledge systems.) Digital storytelling is an appropriate method as Māori is an oral/aural society. It allows Māori to share their stories with others, thus promoting community support at the end of life, befitting a public health approach. Digital storytelling can be a useful method for Māori to express their experiences providing end of life caregiving. © 2015, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. The suitability of visual taphonomic methods for digital photographs: An experimental approach with pig carcasses in a tropical climate.

    Science.gov (United States)

    Ribéreau-Gayon, Agathe; Rando, Carolyn; Morgan, Ruth M; Carter, David O

    2018-05-01

    In the context of increased scrutiny of the methods in forensic sciences, it is essential to ensure that the approaches used in forensic taphonomy to measure decomposition and estimate the postmortem interval are underpinned by robust evidence-based data. Digital photographs are an important source of documentation in forensic taphonomic investigations but the suitability of the current approaches for photographs, rather than real-time remains, is poorly studied which can undermine accurate forensic conclusions. The present study aimed to investigate the suitability of 2D colour digital photographs for evaluating decomposition of exposed human analogues (Sus scrofa domesticus) in a tropical savanna environment (Hawaii), using two published scoring methods; Megyesi et al., 2005 and Keough et al., 2017. It was found that there were significant differences between the real-time and photograph decomposition scores when the Megyesi et al. method was used. However, the Keough et al. method applied to photographs reflected real-time decomposition more closely and thus appears more suitable to evaluate pig decomposition from 2D photographs. The findings indicate that the type of scoring method used has a significant impact on the ability to accurately evaluate the decomposition of exposed pig carcasses from photographs. It was further identified that photographic taphonomic analysis can reach high inter-observer reproducibility. These novel findings are of significant importance for the forensic sciences as they highlight the potential for high quality photograph coverage to provide useful complementary information for the forensic taphonomic investigation. New recommendations to develop robust transparent approaches adapted to photographs in forensic taphonomy are suggested based on these findings. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Digital photography and transparency-based methods for measuring wound surface area.

    Science.gov (United States)

    Bhedi, Amul; Saxena, Atul K; Gadani, Ravi; Patel, Ritesh

    2013-04-01

    To compare and determine a credible method of measurement of wound surface area by linear, transparency, and photographic methods for monitoring progress of wound healing accurately and ascertaining whether these methods are significantly different. From April 2005 to December 2006, 40 patients (30 men, 5 women, 5 children) admitted to the surgical ward of Shree Sayaji General Hospital, Baroda, had clean as well as infected wound following trauma, debridement, pressure sore, venous ulcer, and incision and drainage. Wound surface areas were measured by these three methods (linear, transparency, and photographic methods) simultaneously on alternate days. The linear method is statistically and significantly different from transparency and photographic methods (P value transparency and photographic methods (P value >0.05). Photographic and transparency methods provided measurements of wound surface area with equivalent result and there was no statistically significant difference between these two methods.

  13. Employer Branding

    OpenAIRE

    Stroblová, Zuzana

    2017-01-01

    The aim of the Master Thesis is to describe how to build Employer Brand a company. It is based on the description of Employer Branding project of a particular company and the evaluation its process. The thesis is a case study and consists of theoretical and practical part. The theoretical part focuses on trends and changes in leadership approach, definition of Employer Branding and HR Marketing. The practical part deals with the brand building process itself, describes the outputs of the proj...

  14. Employer branding

    OpenAIRE

    Mičková, Kateřina

    2008-01-01

    The demand for qualified employees is higher then the offering, both in Czech republic and internationally. Demand for specific skills, in addition to a greater demand for workforce generally, is making employee recruitment and retention much more difficult and expensive. Employer Branding claims to be an answer to this new challenge. This international concept focuses on developing an "employer brand" - mental image of a company as an employer. To achieve this, it is necessary to demonstrate...

  15. The digital structural analysis of cadmium selenide crystals by a method of ion beam thinning for high resolution electron microscopy

    International Nuclear Information System (INIS)

    Kanaya, Koichi; Baba, Norio; Naka, Michiaki; Kitagawa, Yukihisa; Suzuki, Kunio

    1986-01-01

    A digital processing method using a scanning densitometer system for structural analysis of electron micrographs was successfully applied to a study of cadmium selenide crystals, which were prepared by an argon-ion beam thinning method. Based on Fourier techniques for structural analysis from a computer-generated diffractogram, it was demonstrated that when cadmium selenide crystals were sufficiently thin to display the higher order diffraction spots at a high resolution approaching the atomic level, they constitute an alternative hexagonal lattice of imperfect wurtzite phase from a superposition of individual harmonic images by the enhanced scattering amplitude and corrected phase. From the structural analysis data, a Fourier synthetic lattice image was reconstructed, representing the precise location and three-dimensional arrangement of each of the atoms in the unit cell. Extensively enhanced lattice defect images of dislocations and stacking faults were also derived and shown graphically. (author)

  16. Pulmonary arteriography by digital subtraction angiographic method in cyanotic heart disease with pulmonary stenosis or pulmonary atresia

    International Nuclear Information System (INIS)

    Kobayashi, Junjiro; Hirose, Hajime; Nakano, Susumu

    1985-01-01

    Pulmonary arteriography was performed by digital subtraction angiographic (DSA) method in 10 patients with cyanotic heart disease associated with pulmonary stenosis or pulmonary atresia. Ten patients consisted of five patients with tetralogy of Fallot, three with single ventricle and pulmonary stenosis, and two with pseudotruncus arteriosus. Hepato-clavicular position was taken in four patients. Pulmonary artery and its main branches were opacified and recognized clearly, and their diameter could be measured accurately with a small amount of contrast medium. There was a good correlation between the diameter of pulmonary artery measured by DSA and that measured by conventional pulmonary arteriography. DSA is a useful method for evaluating the size and the stenosis of pulmonary artery especially in small cyanotic infants. (author)

  17. The Expanding Digital Media Landscape of Qualitative and Decolonizing Research: Examining Collaborative Podcasting as a Research Method

    Directory of Open Access Journals (Sweden)

    Lindsay Day

    2017-12-01

    Full Text Available Technology of the twenty-first century has transformed our ability to create, modify, store, and share digital media and, in so doing, has presented new possibilities for how social science research can be conducted and mobilized. This paper introduces the use of collaborative podcasting as a research method of critical inquiry and knowledge mobilization. Using a case study, we describe the methodological process that our transdisciplinary team engaged in to create the Water Dialogues podcast, a collaborative initiative stemming from a larger research project examining approaches to implementing Indigenous and Western knowledge in water research and management. We situate collaborative podcasting within an expanding field of collaborative and participatory media practice in social research, and consider how the method may align with and support research within a decolonizing agenda.

  18. Multi-method and innovative approaches to researching the learning and social practices of young digital users

    DEFF Research Database (Denmark)

    Vittadini, Nicoletta; Carlo, Simone; Gilje, Øystein

    2014-01-01

    One of the most significant challenges in researching the social aspects of contemporary societies is to adapt the methodological approach to complex digital media environments. Learning processes take place in this complex environment, and they include formal and informal experiences (learning...... in school, home, and real-virtual communities), peer cultures and inter-generational connections, production and creation as relevant activities, and personal interests as a focal point. Methods used in the study of learning and the social practices of young people must take into account four key issues......: boundaries between online and offline experiences are blurring; young people act performatively, knowingly, or reflexively; and their activities cannot be understood through the use of a single method, but require the use of multiple tools of investigation. The article discusses three methodological issues...

  19. Multi-method and innovative approaches to researching the learning and social practices of young digital users

    DEFF Research Database (Denmark)

    Vittadini, Nicoletta; Carlo, Simone; Gilje, Øystein

    2012-01-01

    One of the most significant challenges in researching the social aspects of contemporary societies is to adapt the methodological approach to complex digital media environments. Learning processes take place in this complex environment, and they include formal and informal experiences (learning...... in school, home, and real-virtual communities), peer cultures and intergenerational connections, production and creation as relevant activities, and personal interests as a focal point. Methods used in the study of learning and the social practices of young people must take into account four key issues......: boundaries between online and offline experiences are blurring; young people act performatively; young people act knowingly or reflexively; and the activities of young people cannot be understood through the use of a single method but require the use of multiple tools of investigation. The article discusses...

  20. Researching Employment Relations: A Self-Reflexive Analysis of a Multi-Method, School-Based Project

    Science.gov (United States)

    McDonald, Paula; Graham, Tina

    2011-01-01

    Drawing on primary data and adjunct material, this article adopts a critical self-reflexive approach to a three-year, Australian Research Council-funded project that explored themes around "employment citizenship" for high school students in Queensland. The article addresses three overlapping areas that reflect some of the central…