An in fiber experimental approach to photonic quantum digital signatures that does not require quantum memory

NASA Astrophysics Data System (ADS)

Collins, Robert J.; Donaldon, Ross J.; Dunjko, Vedran; Wallden, Petros; Clarke, Patrick J.; Andersson, Erika; Jeffers, John; Buller, Gerald S.

2014-10-01

Classical digital signatures are commonly used in e-mail, electronic financial transactions and other forms of electronic communications to ensure that messages have not been tampered with in transit, and that messages are transferrable. The security of commonly used classical digital signature schemes relies on the computational difficulty of inverting certain mathematical functions. However, at present, there are no such one-way functions which have been proven to be hard to invert. With enough computational resources certain implementations of classical public key cryptosystems can be, and have been, broken with current technology. It is nevertheless possible to construct information-theoretically secure signature schemes, including quantum digital signature schemes. Quantum signature schemes can be made information theoretically secure based on the laws of quantum mechanics, while classical comparable protocols require additional resources such as secret communication and a trusted authority. Early demonstrations of quantum digital signatures required quantum memory, rendering them impractical at present. Our present implementation is based on a protocol that does not require quantum memory. It also uses the new technique of unambiguous quantum state elimination, Here we report experimental results for a test-bed system, recorded with a variety of different operating parameters, along with a discussion of aspects of the system security.

Complex Digital Visual Systems

ERIC Educational Resources Information Center

Sweeny, Robert W.

2013-01-01

This article identifies possibilities for data visualization as art educational research practice. The author presents an analysis of the relationship between works of art and digital visual culture, employing aspects of network analysis drawn from the work of Barabási, Newman, and Watts (2006) and Castells (1994). Describing complex network…

Repetitive element signature-based visualization, distance computation, and classification of 1766 microbial genomes.

PubMed

Lee, Kang-Hoon; Shin, Kyung-Seop; Lim, Debora; Kim, Woo-Chan; Chung, Byung Chang; Han, Gyu-Bum; Roh, Jeongkyu; Cho, Dong-Ho; Cho, Kiho

2015-07-01

The genomes of living organisms are populated with pleomorphic repetitive elements (REs) of varying densities. Our hypothesis that genomic RE landscapes are species/strain/individual-specific was implemented into the Genome Signature Imaging system to visualize and compute the RE-based signatures of any genome. Following the occurrence profiling of 5-nucleotide REs/words, the information from top-50 frequency words was transformed into a genome-specific signature and visualized as Genome Signature Images (GSIs), using a CMYK scheme. An algorithm for computing distances among GSIs was formulated using the GSIs' variables (word identity, frequency, and frequency order). The utility of the GSI-distance computation system was demonstrated with control genomes. GSI-based computation of genome-relatedness among 1766 microbes (117 archaea and 1649 bacteria) identified their clustering patterns; although the majority paralleled the established classification, some did not. The Genome Signature Imaging system, with its visualization and distance computation functions, enables genome-scale evolutionary studies involving numerous genomes with varying sizes. Copyright © 2015 Elsevier Inc. All rights reserved.

A Simple Model-Based Approach to Inferring and Visualizing Cancer Mutation Signatures

PubMed Central

Shiraishi, Yuichi; Tremmel, Georg; Miyano, Satoru; Stephens, Matthew

2015-01-01

Recent advances in sequencing technologies have enabled the production of massive amounts of data on somatic mutations from cancer genomes. These data have led to the detection of characteristic patterns of somatic mutations or “mutation signatures” at an unprecedented resolution, with the potential for new insights into the causes and mechanisms of tumorigenesis. Here we present new methods for modelling, identifying and visualizing such mutation signatures. Our methods greatly simplify mutation signature models compared with existing approaches, reducing the number of parameters by orders of magnitude even while increasing the contextual factors (e.g. the number of flanking bases) that are accounted for. This improves both sensitivity and robustness of inferred signatures. We also provide a new intuitive way to visualize the signatures, analogous to the use of sequence logos to visualize transcription factor binding sites. We illustrate our new method on somatic mutation data from urothelial carcinoma of the upper urinary tract, and a larger dataset from 30 diverse cancer types. The results illustrate several important features of our methods, including the ability of our new visualization tool to clearly highlight the key features of each signature, the improved robustness of signature inferences from small sample sizes, and more detailed inference of signature characteristics such as strand biases and sequence context effects at the base two positions 5′ to the mutated site. The overall framework of our work is based on probabilistic models that are closely connected with “mixed-membership models” which are widely used in population genetic admixture analysis, and in machine learning for document clustering. We argue that recognizing these relationships should help improve understanding of mutation signature extraction problems, and suggests ways to further improve the statistical methods. Our methods are implemented in an R package pmsignature (https

Implementation of Digital Signature Using Aes and Rsa Algorithms as a Security in Disposition System af Letter

NASA Astrophysics Data System (ADS)

Siregar, H.; Junaeti, E.; Hayatno, T.

2017-03-01

Activities correspondence is often used by agencies or companies, so that institutions or companies set up a special division to handle issues related to the letter management. Most of the distribution of letters using electronic media, then the letter should be kept confidential in order to avoid things that are not desirable. Techniques that can be done to meet the security aspect is by using cryptography or by giving a digital signature. The addition of asymmetric and symmetric algorithms, i.e. RSA and AES algorithms, on the digital signature had been done in this study to maintain data security. The RSA algorithm was used during the process of giving digital signature, while the AES algorithm was used during the process of encoding a message that will be sent to the receiver. Based on the research can be concluded that the additions of AES and RSA algorithms on the digital signature meet four objectives of cryptography: Secrecy, Data Integrity, Authentication and Non-repudiation.

Understanding Digital Note-Taking Practice for Visualization.

PubMed

Willett, Wesley; Goffin, Pascal; Isenberg, Petra

2015-05-13

We present results and design implications from a study of digital note-taking practice to examine how visualization can support revisitation, reflection, and collaboration around notes. As digital notebooks become common forms of external memory, keeping track of volumes of content is increasingly difficult. Information visualization tools can help give note-takers an overview of their content and allow them to explore diverse sets of notes, find and organize related content, and compare their notes with their collaborators. To ground the design of such tools, we conducted a detailed mixed-methods study of digital note-taking practice. We identify a variety of different editing, organization, and sharing methods used by digital note-takers, many of which result in notes becoming "lost in the pile''. These findings form the basis for our design considerations that examine how visualization can support the revisitation, organization, and sharing of digital notes.

Towards a Visual Quality Metric for Digital Video

NASA Technical Reports Server (NTRS)

Watson, Andrew B.

1998-01-01

The advent of widespread distribution of digital video creates a need for automated methods for evaluating visual quality of digital video. This is particularly so since most digital video is compressed using lossy methods, which involve the controlled introduction of potentially visible artifacts. Compounding the problem is the bursty nature of digital video, which requires adaptive bit allocation based on visual quality metrics. In previous work, we have developed visual quality metrics for evaluating, controlling, and optimizing the quality of compressed still images. These metrics incorporate simplified models of human visual sensitivity to spatial and chromatic visual signals. The challenge of video quality metrics is to extend these simplified models to temporal signals as well. In this presentation I will discuss a number of the issues that must be resolved in the design of effective video quality metrics. Among these are spatial, temporal, and chromatic sensitivity and their interactions, visual masking, and implementation complexity. I will also touch on the question of how to evaluate the performance of these metrics.

Automated Assessment of Visual Quality of Digital Video

NASA Technical Reports Server (NTRS)

Watson, Andrew B.; Ellis, Stephen R. (Technical Monitor)

1997-01-01

The advent of widespread distribution of digital video creates a need for automated methods for evaluating visual quality of digital video. This is particularly so since most digital video is compressed using lossy methods, which involve the controlled introduction of potentially visible artifacts. Compounding the problem is the bursty nature of digital video, which requires adaptive bit allocation based on visual quality metrics. In previous work, we have developed visual quality metrics for evaluating, controlling, and optimizing the quality of compressed still images[1-4]. These metrics incorporate simplified models of human visual sensitivity to spatial and chromatic visual signals. The challenge of video quality metrics is to extend these simplified models to temporal signals as well. In this presentation I will discuss a number of the issues that must be resolved in the design of effective video quality metrics. Among these are spatial, temporal, and chromatic sensitivity and their interactions, visual masking, and implementation complexity. I will also touch on the question of how to evaluate the performance of these metrics.

Experimental measurement-device-independent quantum digital signatures.

PubMed

Roberts, G L; Lucamarini, M; Yuan, Z L; Dynes, J F; Comandar, L C; Sharpe, A W; Shields, A J; Curty, M; Puthoor, I V; Andersson, E

2017-10-23

The development of quantum networks will be paramount towards practical and secure telecommunications. These networks will need to sign and distribute information between many parties with information-theoretic security, requiring both quantum digital signatures (QDS) and quantum key distribution (QKD). Here, we introduce and experimentally realise a quantum network architecture, where the nodes are fully connected using a minimum amount of physical links. The central node of the network can act either as a totally untrusted relay, connecting the end users via the recently introduced measurement-device-independent (MDI)-QKD, or as a trusted recipient directly communicating with the end users via QKD. Using this network, we perform a proof-of-principle demonstration of QDS mediated by MDI-QKD. For that, we devised an efficient protocol to distil multiple signatures from the same block of data, thus reducing the statistical fluctuations in the sample and greatly enhancing the final QDS rate in the finite-size scenario.

Basis for the implementation of digital signature in Argentine's health environment

NASA Astrophysics Data System (ADS)

Escobar, P. P.; Formica, M.

2007-11-01

The growth of telemedical applications and electronic transactions in health environments is paced by the constant technology evolution. This implies a big cultural change in traditional medicine and in hospital information systems' users which arrival is delayed, basically, by the lack of solid laws and a well defined role-based infrastructure. The use of digital signature as a mean of identification, authentication, confidentiality and non-repudiation is the most suitable tool for assuring the electronic transactions and patient's data protection. The implementation of a Public Key Infrastructure (PKI) in health environment allows for authentication, encryption and use of digital signature for assuring confidentiality and control of the movement of sensitive information. This work defines the minimum technological, legal and procedural basis for a successful PKI implementation and establishes the roles for the different actors in the chain of confidence in the public health environment of Argentine.

Deep Learning Predicts Correlation between a Functional Signature of Higher Visual Areas and Sparse Firing of Neurons.

PubMed

Zhuang, Chengxu; Wang, Yulong; Yamins, Daniel; Hu, Xiaolin

2017-01-01

Visual information in the visual cortex is processed in a hierarchical manner. Recent studies show that higher visual areas, such as V2, V3, and V4, respond more vigorously to images with naturalistic higher-order statistics than to images lacking them. This property is a functional signature of higher areas, as it is much weaker or even absent in the primary visual cortex (V1). However, the mechanism underlying this signature remains elusive. We studied this problem using computational models. In several typical hierarchical visual models including the AlexNet, VggNet, and SHMAX, this signature was found to be prominent in higher layers but much weaker in lower layers. By changing both the model structure and experimental settings, we found that the signature strongly correlated with sparse firing of units in higher layers but not with any other factors, including model structure, training algorithm (supervised or unsupervised), receptive field size, and property of training stimuli. The results suggest an important role of sparse neuronal activity underlying this special feature of higher visual areas.

Deep Learning Predicts Correlation between a Functional Signature of Higher Visual Areas and Sparse Firing of Neurons

PubMed Central

Zhuang, Chengxu; Wang, Yulong; Yamins, Daniel; Hu, Xiaolin

2017-01-01

Visual information in the visual cortex is processed in a hierarchical manner. Recent studies show that higher visual areas, such as V2, V3, and V4, respond more vigorously to images with naturalistic higher-order statistics than to images lacking them. This property is a functional signature of higher areas, as it is much weaker or even absent in the primary visual cortex (V1). However, the mechanism underlying this signature remains elusive. We studied this problem using computational models. In several typical hierarchical visual models including the AlexNet, VggNet, and SHMAX, this signature was found to be prominent in higher layers but much weaker in lower layers. By changing both the model structure and experimental settings, we found that the signature strongly correlated with sparse firing of units in higher layers but not with any other factors, including model structure, training algorithm (supervised or unsupervised), receptive field size, and property of training stimuli. The results suggest an important role of sparse neuronal activity underlying this special feature of higher visual areas. PMID:29163117

Experimental demonstration of quantum digital signatures over 43 dB channel loss using differential phase shift quantum key distribution.

PubMed

Collins, Robert J; Amiri, Ryan; Fujiwara, Mikio; Honjo, Toshimori; Shimizu, Kaoru; Tamaki, Kiyoshi; Takeoka, Masahiro; Sasaki, Masahide; Andersson, Erika; Buller, Gerald S

2017-06-12

Ensuring the integrity and transferability of digital messages is an important challenge in modern communications. Although purely mathematical approaches exist, they usually rely on the computational complexity of certain functions, in which case there is no guarantee of long-term security. Alternatively, quantum digital signatures offer security guaranteed by the physical laws of quantum mechanics. Prior experimental demonstrations of quantum digital signatures in optical fiber have typically been limited to operation over short distances and/or operated in a laboratory environment. Here we report the experimental transmission of quantum digital signatures over channel losses of up to 42.8 ± 1.2 dB in a link comprised of 90 km of installed fiber with additional optical attenuation introduced to simulate longer distances. The channel loss of 42.8 ± 1.2 dB corresponds to an equivalent distance of 134.2 ± 3.8 km and this represents the longest effective distance and highest channel loss that quantum digital signatures have been shown to operate over to date. Our theoretical model indicates that this represents close to the maximum possible channel attenuation for this quantum digital signature protocol, defined as the loss for which the signal rate is comparable to the dark count rate of the detectors.

Integration of today's digital state with tomorrow's visual environment

NASA Astrophysics Data System (ADS)

Fritsche, Dennis R.; Liu, Victor; Markandey, Vishal; Heimbuch, Scott

1996-03-01

New developments in visual communication technologies, and the increasingly digital nature of the industry infrastructure as a whole, are converging to enable new visual environments with an enhanced visual component in interaction, entertainment, and education. New applications and markets can be created, but this depends on the ability of the visual communications industry to provide market solutions that are cost effective and user friendly. Industry-wide cooperation in the development of integrated, open architecture applications enables the realization of such market solutions. This paper describes the work being done by Texas Instruments, in the development of its Digital Light ProcessingTM technology, to support the development of new visual communications technologies and applications.

A Fast lattice-based polynomial digital signature system for m-commerce

NASA Astrophysics Data System (ADS)

Wei, Xinzhou; Leung, Lin; Anshel, Michael

2003-01-01

The privacy and data integrity are not guaranteed in current wireless communications due to the security hole inside the Wireless Application Protocol (WAP) version 1.2 gateway. One of the remedies is to provide an end-to-end security in m-commerce by applying application level security on top of current WAP1.2. The traditional security technologies like RSA and ECC applied on enterprise's server are not practical for wireless devices because wireless devices have relatively weak computation power and limited memory compared with server. In this paper, we developed a lattice based polynomial digital signature system based on NTRU's Polynomial Authentication and Signature Scheme (PASS), which enabled the feasibility of applying high-level security on both server and wireless device sides.

Detecting and visualizing weak signatures in hyperspectral data

NASA Astrophysics Data System (ADS)

MacPherson, Duncan James

This thesis evaluates existing techniques for detecting weak spectral signatures from remotely sensed hyperspectral data. Algorithms are presented that successfully detect hard-to-find 'mystery' signatures in unknown cluttered backgrounds. The term 'mystery' is used to describe a scenario where the spectral target and background endmembers are unknown. Sub-Pixel analysis and background suppression are used to find deeply embedded signatures which can be less than 10% of the total signal strength. Existing 'mystery target' detection algorithms are derived and compared. Several techniques are shown to be superior both visually and quantitatively. Detection performance is evaluated using confidence metrics that are developed. A multiple algorithm approach is shown to improve detection confidence significantly. Although the research focuses on remote sensing applications, the algorithms presented can be applied to a wide variety of diverse fields such as medicine, law enforcement, manufacturing, earth science, food production, and astrophysics. The algorithms are shown to be general and can be applied to both the reflective and emissive parts of the electromagnetic spectrum. The application scope is a broad one and the final results open new opportunities for many specific applications including: land mine detection, pollution and hazardous waste detection, crop abundance calculations, volcanic activity monitoring, detecting diseases in food, automobile or airplane target recognition, cancer detection, mining operations, extracting galactic gas emissions, etc.

Visual Design Guidelines for Improving Learning from Dynamic and Interactive Digital Text

ERIC Educational Resources Information Center

Jin, Sung-Hee

2013-01-01

Despite the dynamic and interactive features of digital text, the visual design guidelines for digital text are similar to those for printed text. The purpose of this study was to develop visual design guidelines for improving learning from dynamic and interactive digital text and to validate them by controlled testing. Two structure design…

Assuring image authenticity within a data grid using lossless digital signature embedding and a HIPAA-compliant auditing system

NASA Astrophysics Data System (ADS)

Lee, Jasper C.; Ma, Kevin C.; Liu, Brent J.

2008-03-01

A Data Grid for medical images has been developed at the Image Processing and Informatics Laboratory, USC to provide distribution and fault-tolerant storage of medical imaging studies across Internet2 and public domain. Although back-up policies and grid certificates guarantee privacy and authenticity of grid-access-points, there still lacks a method to guarantee the sensitive DICOM images have not been altered or corrupted during transmission across a public domain. This paper takes steps toward achieving full image transfer security within the Data Grid by utilizing DICOM image authentication and a HIPAA-compliant auditing system. The 3-D lossless digital signature embedding procedure involves a private 64 byte signature that is embedded into each original DICOM image volume, whereby on the receiving end the signature can to be extracted and verified following the DICOM transmission. This digital signature method has also been developed at the IPILab. The HIPAA-Compliant Auditing System (H-CAS) is required to monitor embedding and verification events, and allows monitoring of other grid activity as well. The H-CAS system federates the logs of transmission and authentication events at each grid-access-point and stores it into a HIPAA-compliant database. The auditing toolkit is installed at the local grid-access-point and utilizes Syslog [1], a client-server standard for log messaging over an IP network, to send messages to the H-CAS centralized database. By integrating digital image signatures and centralized logging capabilities, DICOM image integrity within the Medical Imaging and Informatics Data Grid can be monitored and guaranteed without loss to any image quality.

wHospital: a web-based application with digital signature for drugs dispensing management.

PubMed

Rossi, Lorenzo; Margola, Lorenzo; Manzelli, Vacia; Bandera, Alessandra

2006-01-01

wHospital is the result of an information technology research project, based on the utilization of a web based application for managing the hospital drugs dispensing. Part of wHospital back bone and its key distinguishing characteristic is the adoption of the digital signature system,initially deployed by the Government of Lombardia, a Northern Italy Region, throughout the distribution of smart cards to all the healthcare and hospital staffs. The developed system is a web-based application with a proposed Health Records Digital Signature (HReDS) handshake to comply with the national law and with the Joint Commission International Standards. The prototype application, for a single hospital Operative Unit (OU), has focused on data and process management, related to drug therapy. Following a multi-faceted selection process, the Infective Disease OU of the Hospital in Busto Arsizio, Lombardia, was chosen for the development and prototype implementation. The project lead time, from user requirement analysis to training and deployment was approximately 8 months. This paper highlights the applied project methodology, the system architecture, and the achieved preliminary results.

The geometric signature: Quantifying landslide-terrain types from digital elevation models

USGS Publications Warehouse

Pike, R.J.

1988-01-01

Topography of various types and scales can be fingerprinted by computer analysis of altitude matrices (digital elevation models, or DEMs). The critical analytic tool is the geometric signature, a set of measures that describes topographic form well enough to distinguish among geomorphically disparate landscapes. Different surficial processes create topography with diagnostic forms that are recognizable in the field. The geometric signature abstracts those forms from contour maps or their DEMs and expresses them numerically. This multivariate characterization enables once-in-tractable problems to be addressed. The measures that constitute a geometric signature express different but complementary attributes of topographic form. Most parameters used here are statistical estimates of central tendency and dispersion for five major categories of terrain geometry; altitude, altitude variance spectrum, slope between slope reversals, and slope and its curvature at fixed slope lengths. As an experimental application of geometric signatures, two mapped terrain types associated with different processes of shallow landsliding in Marin County, California, were distinguished consistently by a 17-variable description of topography from 21??21 DEMs (30-m grid spacing). The small matrix is a statistical window that can be used to scan large DEMs by computer, thus potentially automating the mapping of contrasting terrain types. The two types in Marin County host either (1) slow slides: earth flows and slump-earth flows, or (2) rapid flows: debris avalanches and debris flows. The signature approach should adapt to terrain taxonomy and mapping in other areas, where conditions differ from those in Central California. ?? 1988 International Association for Mathematical Geology.

Radiogenomics analysis identifies correlations of digital mammography with clinical molecular signatures in breast cancer.

PubMed

Tamez-Peña, Jose-Gerardo; Rodriguez-Rojas, Juan-Andrés; Gomez-Rueda, Hugo; Celaya-Padilla, Jose-Maria; Rivera-Prieto, Roxana-Alicia; Palacios-Corona, Rebeca; Garza-Montemayor, Margarita; Cardona-Huerta, Servando; Treviño, Victor

2018-01-01

In breast cancer, well-known gene expression subtypes have been related to a specific clinical outcome. However, their impact on the breast tissue phenotype has been poorly studied. Here, we investigate the association of imaging data of tumors to gene expression signatures from 71 patients with breast cancer that underwent pre-treatment digital mammograms and tumor biopsies. From digital mammograms, a semi-automated radiogenomics analysis generated 1,078 features describing the shape, signal distribution, and texture of tumors along their contralateral image used as control. From tumor biopsy, we estimated the OncotypeDX and PAM50 recurrence scores using gene expression microarrays. Then, we used multivariate analysis under stringent cross-validation to train models predicting recurrence scores. Few univariate features reached Spearman correlation coefficients above 0.4. Nevertheless, multivariate analysis yielded significantly correlated models for both signatures (correlation of OncotypeDX = 0.49 ± 0.07 and PAM50 = 0.32 ± 0.10 in stringent cross-validation and OncotypeDX = 0.83 and PAM50 = 0.78 for a unique model). Equivalent models trained from the unaffected contralateral breast were not correlated suggesting that the image signatures were tumor-specific and that overfitting was not a considerable issue. We also noted that models were improved by combining clinical information (triple negative status and progesterone receptor). The models used mostly wavelets and fractal features suggesting their importance to capture tumor information. Our results suggest that molecular-based recurrence risk and breast cancer subtypes have observable radiographic phenotypes. To our knowledge, this is the first study associating mammographic information to gene expression recurrence signatures.

Visualizing Breath using Digital Holography

NASA Astrophysics Data System (ADS)

Hobson, P. R.; Reid, I. D.; Wilton, J. B.

2013-02-01

Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

Digital versus Traditional: Secondary Students with Visual Impairments' Perceptions of a Digital Algebra Textbook

ERIC Educational Resources Information Center

Bouck, Emily C.; Weng, Pei-Lin; Satsangi, Rajiv

2016-01-01

Introduction: Digital textbooks are increasingly marketed and used, yet little research examines this medium. Within the limited research, even less investigates the role of digital textbooks in mathematics--a challenging content area for many students, but especially for students with visual impairments. Methods: Through a qualitative analysis,…

Synthesis of optical polarization signatures of military aircraft

NASA Astrophysics Data System (ADS)

Egan, Walter G.; Duggin, Michael J.

2002-01-01

Focal plane wide band IR imagery will be compared with visual wide band focal plane digital imagery of a camouflaged B-52 bomber. Extreme enhancement is possible using digital polarized imagery. The experimental observations will be compared to theoretical calculations and modeling result of both specular and shadowed areas to allow extrapolations to the synthesis of the optical polarization signatures of other aircraft. The relationship of both the specular and the shadowed areas to surface structure, orientation, specularlity, roughness, shadowing and the complex index of refraction will be illustrated. The imagery was obtained in two plane-polarized directions. Many aircraft locations were measured as well as sky background.

European dental students' opinions about visual and digital tooth colour determination systems.

PubMed

Dozic, Alma; Kharbanda, Aron K; Kamell, Hassib; Brand, Henk S

2011-12-01

The aim of the study was to investigate students' opinion about visual and digital tooth colour determination education at different European dental schools. A cross-sectional web-based survey was created, containing nine dichotomous, multiple choice and 5-point Likert scale questions. The questionnaire was distributed amongst students of 40 European dental schools. Seven hundred and ninety-nine completed questionnaires from students of 15 dental schools were analysed statistically. Vitapan Classical and Vitapan 3D-Master are the most frequently used visual determination systems at European dental schools. Most students responded with "neutral" regarding whether they find it easy to identify the colour of teeth with a visual determination system (range 2.8-3.6). A minority of the dental students had received education in digital imaging systems (2-47%). The Easyshade was the most frequently mentioned digital system. The majority of the students who did not receive education on digital systems would like to see this topic added to the curriculum (77-100%). The dental students who had worked with both methods found it significantly easier to determine tooth colour with a digital system than with a visual system (mean score 3.5 ± 0.8 vs. 3.0 ± 0.8). Tooth colour determination programmes show a considerable variation across European dental schools. Based upon the outcomes of this study, students prefer digital imaging systems over visual systems, and like to have (more) education about digital tooth colour imaging. Copyright © 2011 Elsevier Ltd. All rights reserved.

Radiogenomics analysis identifies correlations of digital mammography with clinical molecular signatures in breast cancer

PubMed Central

Tamez-Peña, Jose-Gerardo; Rodriguez-Rojas, Juan-Andrés; Gomez-Rueda, Hugo; Celaya-Padilla, Jose-Maria; Rivera-Prieto, Roxana-Alicia; Palacios-Corona, Rebeca; Garza-Montemayor, Margarita; Cardona-Huerta, Servando

2018-01-01

In breast cancer, well-known gene expression subtypes have been related to a specific clinical outcome. However, their impact on the breast tissue phenotype has been poorly studied. Here, we investigate the association of imaging data of tumors to gene expression signatures from 71 patients with breast cancer that underwent pre-treatment digital mammograms and tumor biopsies. From digital mammograms, a semi-automated radiogenomics analysis generated 1,078 features describing the shape, signal distribution, and texture of tumors along their contralateral image used as control. From tumor biopsy, we estimated the OncotypeDX and PAM50 recurrence scores using gene expression microarrays. Then, we used multivariate analysis under stringent cross-validation to train models predicting recurrence scores. Few univariate features reached Spearman correlation coefficients above 0.4. Nevertheless, multivariate analysis yielded significantly correlated models for both signatures (correlation of OncotypeDX = 0.49 ± 0.07 and PAM50 = 0.32 ± 0.10 in stringent cross-validation and OncotypeDX = 0.83 and PAM50 = 0.78 for a unique model). Equivalent models trained from the unaffected contralateral breast were not correlated suggesting that the image signatures were tumor-specific and that overfitting was not a considerable issue. We also noted that models were improved by combining clinical information (triple negative status and progesterone receptor). The models used mostly wavelets and fractal features suggesting their importance to capture tumor information. Our results suggest that molecular-based recurrence risk and breast cancer subtypes have observable radiographic phenotypes. To our knowledge, this is the first study associating mammographic information to gene expression recurrence signatures. PMID:29596496

Electronic medical archives: a different approach to applying re-signing mechanisms to digital signatures.

PubMed

Chen, Tzer-Long; Lin, Frank Y S

2011-08-01

Electronic medical records can be defined as a digital format of the traditionally paper-based anamneses, which contains the history of a patient such as his somewhat illness, current health problems, and his chronic treatments. An electronic anamnesis is meant to make the patient's health information more conveniently accessible and transferable between different medical institutions and also easier to be kept quite a long time. Because of such transferability and accessibility of electronic anamneses, we can use less resource than before on storing the patients' medical information. This also means that medical care providers could save more funds on record-keeping and access a patient's medical background directly since shown on the computer screen more quickly and easily. Overall, the service quality has seemingly improved greatly. However, the usage of electronic anamneses involves in some concerned issues such as its related law declaration, and the security of the patient's confidential information. Because of these concerns, a secure medical networking scheme is taking into consideration. Nowadays, the administrators at the medical institutions are facing more challenges on monitoring computers and network systems, because of dramatic advances in this field. For instance, a trusted third party is authorized to access some medical records for a certain period of time. In regard to the security purpose, all the electronic medical records are embedded with both of the public-key infrastructure (PKI) cryptography and the digital signature technique so as to ensure the records well-protected. Since the signatures will be invalid due to the revocation or time expiration, the security of records under this premise would turn into vulnerable. Hence, we propose a re-signing scheme, whose purpose is to make a going-expired digital signature been resigned in time, in keeping with the premise of not conflicting with the laws, morals, and privacy while maintaining the

High speed digital holographic interferometry for hypersonic flow visualization

NASA Astrophysics Data System (ADS)

Hegde, G. M.; Jagdeesh, G.; Reddy, K. P. J.

2013-06-01

Optical imaging techniques have played a major role in understanding the flow dynamics of varieties of fluid flows, particularly in the study of hypersonic flows. Schlieren and shadowgraph techniques have been the flow diagnostic tools for the investigation of compressible flows since more than a century. However these techniques provide only the qualitative information about the flow field. Other optical techniques such as holographic interferometry and laser induced fluorescence (LIF) have been used extensively for extracting quantitative information about the high speed flows. In this paper we present the application of digital holographic interferometry (DHI) technique integrated with short duration hypersonic shock tunnel facility having 1 ms test time, for quantitative flow visualization. Dynamics of the flow fields in hypersonic/supersonic speeds around different test models is visualized with DHI using a high-speed digital camera (0.2 million fps). These visualization results are compared with schlieren visualization and CFD simulation results. Fringe analysis is carried out to estimate the density of the flow field.

Digital-Visual-Sensory-Design Anthropology: Ethnography, Imagination and Intervention

ERIC Educational Resources Information Center

Pink, Sarah

2014-01-01

In this article I outline how a digital-visual-sensory approach to anthropological ethnography might participate in the making of relationship between design and anthropology. While design anthropology is itself coming of age, the potential of its relationship with applied visual anthropology methodology and theory has not been considered in the…

Neural Signatures of Stimulus Features in Visual Working Memory—A Spatiotemporal Approach

PubMed Central

Jackson, Margaret C.; Klein, Christoph; Mohr, Harald; Shapiro, Kimron L.; Linden, David E. J.

2010-01-01

We examined the neural signatures of stimulus features in visual working memory (WM) by integrating functional magnetic resonance imaging (fMRI) and event-related potential data recorded during mental manipulation of colors, rotation angles, and color–angle conjunctions. The N200, negative slow wave, and P3b were modulated by the information content of WM, and an fMRI-constrained source model revealed a progression in neural activity from posterior visual areas to higher order areas in the ventral and dorsal processing streams. Color processing was associated with activity in inferior frontal gyrus during encoding and retrieval, whereas angle processing involved right parietal regions during the delay interval. WM for color–angle conjunctions did not involve any additional neural processes. The finding that different patterns of brain activity underlie WM for color and spatial information is consistent with ideas that the ventral/dorsal “what/where” segregation of perceptual processing influences WM organization. The absence of characteristic signatures of conjunction-related brain activity, which was generally intermediate between the 2 single conditions, suggests that conjunction judgments are based on the coordinated activity of these 2 streams. PMID:19429863

Noise Source Visualization Using a Digital Voice Recorder and Low-Cost Sensors

PubMed Central

Cho, Yong Thung

2018-01-01

Accurate sound visualization of noise sources is required for optimal noise control. Typically, noise measurement systems require microphones, an analog-digital converter, cables, a data acquisition system, etc., which may not be affordable for potential users. Also, many such systems are not highly portable and may not be convenient for travel. Handheld personal electronic devices such as smartphones and digital voice recorders with relatively lower costs and higher performance have become widely available recently. Even though such devices are highly portable, directly implementing them for noise measurement may lead to erroneous results since such equipment was originally designed for voice recording. In this study, external microphones were connected to a digital voice recorder to conduct measurements and the input received was processed for noise visualization. In this way, a low cost, compact sound visualization system was designed and introduced to visualize two actual noise sources for verification with different characteristics: an enclosed loud speaker and a small air compressor. Reasonable accuracy of noise visualization for these two sources was shown over a relatively wide frequency range. This very affordable and compact sound visualization system can be used for many actual noise visualization applications in addition to educational purposes. PMID:29614038

Issues and approaches for electronic document approval and transmittal using digital signatures and text authentication: Prototype documentation

NASA Astrophysics Data System (ADS)

Boling, M. E.

1989-09-01

Prototypes were assembled pursuant to recommendations made in report K/DSRD-96, Issues and Approaches for Electronic Document Approval and Transmittal Using Digital Signatures and Text Authentication, and to examine and discover the possibilities for integrating available hardware and software to provide cost effective systems for digital signatures and text authentication. These prototypes show that on a LAN, a multitasking, windowed, mouse/keyboard menu-driven interface can be assembled to provide easy and quick access to bit-mapped images of documents, electronic forms and electronic mail messages with a means to sign, encrypt, deliver, receive or retrieve and authenticate text and signatures. In addition they show that some of this same software may be used in a classified environment using host to terminal transactions to accomplish these same operations. Finally, a prototype was developed demonstrating that binary files may be signed electronically and sent by point to point communication and over ARPANET to remote locations where the authenticity of the code and signature may be verified. Related studies on the subject of electronic signatures and text authentication using public key encryption were done within the Department of Energy. These studies include timing studies of public key encryption software and hardware and testing of experimental user-generated host resident software for public key encryption. This software used commercially available command-line source code. These studies are responsive to an initiative within the Office of the Secretary of Defense (OSD) for the protection of unclassified but sensitive data. It is notable that these related studies are all built around the same commercially available public key encryption products from the private sector and that the software selection was made independently by each study group.

Low-cost digital dynamic visualization system

NASA Astrophysics Data System (ADS)

Asundi, Anand K.; Sajan, M. R.

1995-05-01

High speed photographic systems like the image rotation camera, the Cranz Schardin camera and the drum camera are typically used for recording and visualization of dynamic events in stress analysis, fluid mechanics, etc. All these systems are fairly expensive and generally not simple to use. Furthermore they are all based on photographic film recording systems requiring time consuming and tedious wet processing of the films. Currently digital cameras are replacing to certain extent the conventional cameras for static experiments. Recently, there is lot of interest in developing and modifying CCD architectures and recording arrangements for dynamic scene analysis. Herein we report the use of a CCD camera operating in the Time Delay and Integration (TDI) mode for digitally recording dynamic scenes. Applications in solid as well as fluid impact problems are presented.

A Hybrid Digital-Signature and Zero-Watermarking Approach for Authentication and Protection of Sensitive Electronic Documents

PubMed Central

Kabir, Muhammad N.; Alginahi, Yasser M.

2014-01-01

This paper addresses the problems and threats associated with verification of integrity, proof of authenticity, tamper detection, and copyright protection for digital-text content. Such issues were largely addressed in the literature for images, audio, and video, with only a few papers addressing the challenge of sensitive plain-text media under known constraints. Specifically, with text as the predominant online communication medium, it becomes crucial that techniques are deployed to protect such information. A number of digital-signature, hashing, and watermarking schemes have been proposed that essentially bind source data or embed invisible data in a cover media to achieve its goal. While many such complex schemes with resource redundancies are sufficient in offline and less-sensitive texts, this paper proposes a hybrid approach based on zero-watermarking and digital-signature-like manipulations for sensitive text documents in order to achieve content originality and integrity verification without physically modifying the cover text in anyway. The proposed algorithm was implemented and shown to be robust against undetected content modifications and is capable of confirming proof of originality whilst detecting and locating deliberate/nondeliberate tampering. Additionally, enhancements in resource utilisation and reduced redundancies were achieved in comparison to traditional encryption-based approaches. Finally, analysis and remarks are made about the current state of the art, and future research issues are discussed under the given constraints. PMID:25254247

Computer aided system for segmentation and visualization of microcalcifications in digital mammograms.

PubMed

Reljin, Branimir; Milosević, Zorica; Stojić, Tomislav; Reljin, Irini

2009-01-01

Two methods for segmentation and visualization of microcalcifications in digital or digitized mammograms are described. First method is based on modern mathematical morphology, while the second one uses the multifractal approach. In the first method, by using an appropriate combination of some morphological operations, high local contrast enhancement, followed by significant suppression of background tissue, irrespective of its radiology density, is obtained. By iterative procedure, this method highly emphasizes only small bright details, possible microcalcifications. In a multifractal approach, from initial mammogram image, a corresponding multifractal "images" are created, from which a radiologist has a freedom to change the level of segmentation. An appropriate user friendly computer aided visualization (CAV) system with embedded two methods is realized. The interactive approach enables the physician to control the level and the quality of segmentation. Suggested methods were tested through mammograms from MIAS database as a gold standard, and from clinical praxis, using digitized films and digital images from full field digital mammograph.

Digitization and Visualization of Greenhouse Tomato Plants in Indoor Environments

PubMed Central

Li, Dawei; Xu, Lihong; Tan, Chengxiang; Goodman, Erik D.; Fu, Daichang; Xin, Longjiao

2015-01-01

This paper is concerned with the digitization and visualization of potted greenhouse tomato plants in indoor environments. For the digitization, an inexpensive and efficient commercial stereo sensor—a Microsoft Kinect—is used to separate visual information about tomato plants from background. Based on the Kinect, a 4-step approach that can automatically detect and segment stems of tomato plants is proposed, including acquisition and preprocessing of image data, detection of stem segments, removing false detections and automatic segmentation of stem segments. Correctly segmented texture samples including stems and leaves are then stored in a texture database for further usage. Two types of tomato plants—the cherry tomato variety and the ordinary variety are studied in this paper. The stem detection accuracy (under a simulated greenhouse environment) for the cherry tomato variety is 98.4% at a true positive rate of 78.0%, whereas the detection accuracy for the ordinary variety is 94.5% at a true positive of 72.5%. In visualization, we combine L-system theory and digitized tomato organ texture data to build realistic 3D virtual tomato plant models that are capable of exhibiting various structures and poses in real time. In particular, we also simulate the growth process on virtual tomato plants by exerting controls on two L-systems via parameters concerning the age and the form of lateral branches. This research may provide useful visual cues for improving intelligent greenhouse control systems and meanwhile may facilitate research on artificial organisms. PMID:25675284

Digitization and visualization of greenhouse tomato plants in indoor environments.

PubMed

Li, Dawei; Xu, Lihong; Tan, Chengxiang; Goodman, Erik D; Fu, Daichang; Xin, Longjiao

2015-02-10

This paper is concerned with the digitization and visualization of potted greenhouse tomato plants in indoor environments. For the digitization, an inexpensive and efficient commercial stereo sensor-a Microsoft Kinect-is used to separate visual information about tomato plants from background. Based on the Kinect, a 4-step approach that can automatically detect and segment stems of tomato plants is proposed, including acquisition and preprocessing of image data, detection of stem segments, removing false detections and automatic segmentation of stem segments. Correctly segmented texture samples including stems and leaves are then stored in a texture database for further usage. Two types of tomato plants-the cherry tomato variety and the ordinary variety are studied in this paper. The stem detection accuracy (under a simulated greenhouse environment) for the cherry tomato variety is 98.4% at a true positive rate of 78.0%, whereas the detection accuracy for the ordinary variety is 94.5% at a true positive of 72.5%. In visualization, we combine L-system theory and digitized tomato organ texture data to build realistic 3D virtual tomato plant models that are capable of exhibiting various structures and poses in real time. In particular, we also simulate the growth process on virtual tomato plants by exerting controls on two L-systems via parameters concerning the age and the form of lateral branches. This research may provide useful visual cues for improving intelligent greenhouse control systems and meanwhile may facilitate research on artificial organisms.

Indoor Navigation by People with Visual Impairment Using a Digital Sign System

PubMed Central

Legge, Gordon E.; Beckmann, Paul J.; Tjan, Bosco S.; Havey, Gary; Kramer, Kevin; Rolkosky, David; Gage, Rachel; Chen, Muzi; Puchakayala, Sravan; Rangarajan, Aravindhan

2013-01-01

There is a need for adaptive technology to enhance indoor wayfinding by visually-impaired people. To address this need, we have developed and tested a Digital Sign System. The hardware and software consist of digitally-encoded signs widely distributed throughout a building, a handheld sign-reader based on an infrared camera, image-processing software, and a talking digital map running on a mobile device. Four groups of subjects—blind, low vision, blindfolded sighted, and normally sighted controls—were evaluated on three navigation tasks. The results demonstrate that the technology can be used reliably in retrieving information from the signs during active mobility, in finding nearby points of interest, and following routes in a building from a starting location to a destination. The visually impaired subjects accurately and independently completed the navigation tasks, but took substantially longer than normally sighted controls. This fully functional prototype system demonstrates the feasibility of technology enabling independent indoor navigation by people with visual impairment. PMID:24116156

Stochastic digital holography for visualizing inside strongly refracting transparent objects.

PubMed

Desse, Jean-Michel; Picart, Pascal

2015-01-01

This paper presents a digital holographic method to visualize and measure refractive index variations, convection currents, or thermal gradients, occurring inside a transparent and refracting object. The proof of principle is provided through the visualization of refractive index variation inside a lighting bulb. Comparison with transmission and reflection holography is also provided. A very good agreement is obtained, thus validating the proposed approach.

Visually lossless compression of digital hologram sequences

NASA Astrophysics Data System (ADS)

Darakis, Emmanouil; Kowiel, Marcin; Näsänen, Risto; Naughton, Thomas J.

2010-01-01

Digital hologram sequences have great potential for the recording of 3D scenes of moving macroscopic objects as their numerical reconstruction can yield a range of perspective views of the scene. Digital holograms inherently have large information content and lossless coding of holographic data is rather inefficient due to the speckled nature of the interference fringes they contain. Lossy coding of still holograms and hologram sequences has shown promising results. By definition, lossy compression introduces errors in the reconstruction. In all of the previous studies, numerical metrics were used to measure the compression error and through it, the coding quality. Digital hologram reconstructions are highly speckled and the speckle pattern is very sensitive to data changes. Hence, numerical quality metrics can be misleading. For example, for low compression ratios, a numerically significant coding error can have visually negligible effects. Yet, in several cases, it is of high interest to know how much lossy compression can be achieved, while maintaining the reconstruction quality at visually lossless levels. Using an experimental threshold estimation method, the staircase algorithm, we determined the highest compression ratio that was not perceptible to human observers for objects compressed with Dirac and MPEG-4 compression methods. This level of compression can be regarded as the point below which compression is perceptually lossless although physically the compression is lossy. It was found that up to 4 to 7.5 fold compression can be obtained with the above methods without any perceptible change in the appearance of video sequences.

Visual and digital comparative tooth colour assessment methods and atomic force microscopy surface roughness.

PubMed

Grundlingh, A A; Grossman, E S; Shrivastava, S; Witcomb, M J

2013-10-01

This study compared digital and visual colour tooth colour assessment methods in a sample of 99 teeth consisting of incisors, canines and pre-molars. The teeth were equally divided between Control, Ozicure Oxygen Activator bleach and Opalescence Quick bleach and subjected to three treatments. Colour readings were recorded at nine intervals by two assessment methods, VITA Easyshade and VITAPAN 3D MASTER TOOTH GUIDE, giving a total of 1782 colour readings. Descriptive and statistical analysis was undertaken using a GLM test for Analysis of Variance for a Fractional Design set at a significance of P < 0.05. Atomic force micros copy was used to examine treated ename surfaces and establish surface roughness. Visual tooth colour assessment showed significance for the independent variables of treatment, number of treatments, tooth type and the combination tooth type and treatment. Digital colour assessment indicated treatment and tooth type to be of significance in tooth colour change. Poor agreement was found between visual and digital colour assessment methods for Control and Ozicure Oxygen Activator treatments. Surface roughness values increased two-fold for Opalescence Quick specimens over the two other treatments, implying that increased light scattering improved digital colour reading. Both digital and visual colour matching methods should be used in tooth bleaching studies to complement each other and to compensate for deficiencies.

Visualization and analysis for multidimensional gene expressions signature of cigarette smoking

NASA Astrophysics Data System (ADS)

Wang, Changbo; Xiao, Zhao; Zhang, Tianlun; Cui, Jin; Pang, Chenming

2011-11-01

Biologists often use gene chip to get massive experimental data in the field of bioscience and chemical sciences. Facing a large amount of experimental data, researchers often need to find out a few interesting data or simple regulations. This paper presents a set of methods to visualize and analyze the data for gene expression signatures of people who smoke. We use the latest research data from National Center for Biotechnology Information. Totally, there are more than 400 thousand expressions data. Using these data, we can use parallel coordinates method to visualize the different gene expressions between smokers and nonsmokers and we can distinguish non-smokers, former smokers and current smokers by using the different colors. It can be easy to find out which gene is more important during the lung cancer angiogenesis in the smoking people. In another way, we can use a hierarchical model to visualize the inner relation of different genes. The location of the nodes shows different expression moment and the distance to the root shows the sequence of the expression. We can use the ring layout to represent all the nodes, and connect the different nodes which are related with color lines. Combined with the parallel coordinates method, the visualization result show the important genes and some inner relation obviously, which is useful for examination and prevention of lung cancer.

Display nonlinearity in digital image processing for visual communications

NASA Astrophysics Data System (ADS)

Peli, Eli

1992-11-01

The luminance emitted from a cathode ray tube (CRT) display is a nonlinear function (the gamma function) of the input video signal voltage. In most analog video systems, compensation for this nonlinear transfer function is implemented in the camera amplifiers. When CRT displays are used to present psychophysical stimuli in vision research, the specific display nonlinearity usually is measured and accounted for to ensure that the luminance of each pixel in the synthetic image property represents the intended value. However, when using digital image processing, the linear analog-to-digital converters store a digital image that is nonlinearly related to the displayed or recorded image. The effect of this nonlinear transformation on a variety of image-processing applications used in visual communications is described.

Display nonlinearity in digital image processing for visual communications

NASA Astrophysics Data System (ADS)

Peli, Eli

1991-11-01

The luminance emitted from a cathode ray tube, (CRT) display is a nonlinear function (the gamma function) of the input video signal voltage. In most analog video systems, compensation for this nonlinear transfer function is implemented in the camera amplifiers. When CRT displays are used to present psychophysical stimuli in vision research, the specific display nonlinearity usually is measured and accounted for to ensure that the luminance of each pixel in the synthetic image properly represents the intended value. However, when using digital image processing, the linear analog-to-digital converters store a digital image that is nonlinearly related to the displayed or recorded image. This paper describes the effect of this nonlinear transformation on a variety of image-processing applications used in visual communications.

Visual Literacy and the Digital Native: An Examination of the Millennial Learner

ERIC Educational Resources Information Center

Brumberger, Eva

2011-01-01

The so-called millennial learners who currently populate college classrooms are purportedly digital natives whose repeated exposure to a host of new technologies has allegedly resulted in enhanced skills in several areas, including those related to technology and visual communication. By extension, the argument has been made that digital natives…

Method and Apparatus for Evaluating the Visual Quality of Processed Digital Video Sequences

NASA Technical Reports Server (NTRS)

Watson, Andrew B. (Inventor)

2002-01-01

A Digital Video Quality (DVQ) apparatus and method that incorporate a model of human visual sensitivity to predict the visibility of artifacts. The DVQ method and apparatus are used for the evaluation of the visual quality of processed digital video sequences and for adaptively controlling the bit rate of the processed digital video sequences without compromising the visual quality. The DVQ apparatus minimizes the required amount of memory and computation. The input to the DVQ apparatus is a pair of color image sequences: an original (R) non-compressed sequence, and a processed (T) sequence. Both sequences (R) and (T) are sampled, cropped, and subjected to color transformations. The sequences are then subjected to blocking and discrete cosine transformation, and the results are transformed to local contrast. The next step is a time filtering operation which implements the human sensitivity to different time frequencies. The results are converted to threshold units by dividing each discrete cosine transform coefficient by its respective visual threshold. At the next stage the two sequences are subtracted to produce an error sequence. The error sequence is subjected to a contrast masking operation, which also depends upon the reference sequence (R). The masked errors can be pooled in various ways to illustrate the perceptual error over various dimensions, and the pooled error can be converted to a visual quality measure.

Visualizing along-strike change in deformation style using analog modeling and digital visualization software

NASA Astrophysics Data System (ADS)

Burberry, C. M.

2012-12-01

It is a well-known phenomenon that deformation style varies in space; both along the strike of a deformed belt and along the strike of individual structures within that belt. This variation in deformation style is traditionally visualized with a series of closely spaced 2D cross-sections. However, the use of 2D section lines implies plane strain along those lines, and the true 3D nature of the deformation is not necessarily captured. By using a combination of remotely sensed data, analog modeling of field datasets and this remote data, and numerical and digital visualization of the finished model, a 3D understanding and restoration of the deformation style within the region can be achieved. The workflow used for this study begins by considering the variation in deformation style which can be observed from satellite images and combining this data with traditional field data, in order to understand the deformation in the region under consideration. The conceptual model developed at this stage is then modeled using a sand and silicone modeling system, where the kinematics and dynamics of the deformation processes can be examined. A series of closely-spaced cross-sections, as well as 3D images of the deformation, are created from the analog model, and input into a digital visualization and modeling system for restoration. In this fashion, a valid 3D model is created where the internal structure of the deformed system can be visualized and mined for information. The region used in the study is the Sawtooth Range, Montana. The region forms part of the Montana Disturbed Belt in the Front Ranges of the Rocky Mountains, along strike from the Alberta Syncline in the Canadian Rocky Mountains. Interpretation of satellite data indicates that the deformation front structures include both folds and thrust structures. The thrust structures vary from hinterland-verging triangle zones to foreland-verging imbricate thrusts along strike, and the folds also vary in geometry along

Visual-area coding technique (VACT): optical parallel implementation of fuzzy logic and its visualization with the digital-halftoning process

NASA Astrophysics Data System (ADS)

Konishi, Tsuyoshi; Tanida, Jun; Ichioka, Yoshiki

1995-06-01

A novel technique, the visual-area coding technique (VACT), for the optical implementation of fuzzy logic with the capability of visualization of the results is presented. This technique is based on the microfont method and is considered to be an instance of digitized analog optical computing. Huge amounts of data can be processed in fuzzy logic with the VACT. In addition, real-time visualization of the processed result can be accomplished.

Digital to analog conversion and visual evaluation of Thematic Mapper data

USGS Publications Warehouse

McCord, James R.; Binnie, Douglas R.; Seevers, Paul M.

1985-01-01

As a part of the National Aeronautics and Space Administration Landsat D Image Data Quality Analysis Program, the Earth Resources Observation Systems Data Center (EDC) developed procedures to optimize the visual information content of Thematic Mapper data and evaluate the resulting photographic products by visual interpretation. A digital-to-analog transfer function was developed which would properly place the digital values on the most useable portion of a film response curve. Individual black-and-white transparencies generated using the resulting look-up tables were utilized in the production of color-composite images with varying band combinations. Four experienced photointerpreters ranked 2-cm-diameter (0. 75 inch) chips of selected image features of each band combination for ease of interpretability. A nonparametric rank-order test determined the significance of interpreter preference for the band combinations.

Digital to Analog Conversion and Visual Evaluation of Thematic Mapper Data

USGS Publications Warehouse

McCord, James R.; Binnie, Douglas R.; Seevers, Paul M.

1985-01-01

As a part of the National Aeronautics and Space Administration Landsat D Image Data Quality Analysis Program, the Earth Resources Observation Systems Data Center (EDC) developed procedures to optimize the visual information content of Thematic Mapper data and evaluate the resulting photographic products by visual interpretation. A digital-to-analog transfer function was developed which would properly place the digital values on the most useable portion of a film response curve. Individual black-and-white transparencies generated using the resulting look-up tables were utilized in the production of color-composite images with varying band combinations. Four experienced photointerpreters ranked 2-cm-diameter (0. 75 inch) chips of selected image features of each band combination for ease of interpretability. A nonparametric rank-order test determined the significance of interpreter preference for the band combinations.

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

PubMed

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.

Theoretical Characterizaiton of Visual Signatures

NASA Astrophysics Data System (ADS)

Kashinski, D. O.; Chase, G. M.; di Nallo, O. E.; Scales, A. N.; Vanderley, D. L.; Byrd, E. F. C.

2015-05-01

We are investigating the accuracy of theoretical models used to predict the visible, ultraviolet, and infrared spectra, as well as other properties, of product materials ejected from the muzzle of currently fielded systems. Recent advances in solid propellants has made the management of muzzle signature (flash) a principle issue in weapons development across the calibers. A priori prediction of the electromagnetic spectra of formulations will allow researchers to tailor blends that yield desired signatures and determine spectrographic detection ranges. Quantum chemistry methods at various levels of sophistication have been employed to optimize molecular geometries, compute unscaled vibrational frequencies, and determine the optical spectra of specific gas-phase species. Electronic excitations are being computed using Time Dependent Density Functional Theory (TD-DFT). A full statistical analysis and reliability assessment of computational results is currently underway. A comparison of theoretical results to experimental values found in the literature is used to assess any affects of functional choice and basis set on calculation accuracy. The status of this work will be presented at the conference. Work supported by the ARL, DoD HPCMP, and USMA.

Constructing Visually-Based Digital Conversations in EFL with VoiceThread

ERIC Educational Resources Information Center

Kent, David

2017-01-01

VoiceThread holds potential to provide students who rarely speak in class a means to create visually-based digital conversations. In light of this, pedagogical affordances of the tool are considered, along with efficacy behind VoiceThread development within English as a Foreign Language contexts. Instructional strategies, supported by examples,…

Real-time visualization and analysis of airflow field by use of digital holography

NASA Astrophysics Data System (ADS)

Di, Jianglei; Wu, Bingjing; Chen, Xin; Liu, Junjiang; Wang, Jun; Zhao, Jianlin

2013-04-01

The measurement and analysis of airflow field is very important in fluid dynamics. For airflow, smoke particles can be added to visually observe the turbulence phenomena by particle tracking technology, but the effect of smoke particles to follow the high speed airflow will reduce the measurement accuracy. In recent years, with the advantage of non-contact, nondestructive, fast and full-field measurement, digital holography has been widely applied in many fields, such as deformation and vibration analysis, particle characterization, refractive index measurement, and so on. In this paper, we present a method to measure the airflow field by use of digital holography. A small wind tunnel model made of acrylic glass is built to control the velocity and direction of airflow. Different shapes of samples such as aircraft wing and cylinder are placed in the wind tunnel model to produce different forms of flow field. With a Mach-Zehnder interferometer setup, a series of digital holograms carrying the information of airflow filed distributions in different states are recorded by CCD camera and corresponding holographic images are numerically reconstructed from the holograms by computer. Then we can conveniently obtain the velocity or pressure information of the airflow deduced from the quantitative phase information of holographic images and visually display the airflow filed and its evolution in the form of a movie. The theory and experiment results show that digital holography is a robust and feasible approach for real-time visualization and analysis of airflow field.

Using Digitized Handheld Space Shuttle Photography for Terrain Visualization

NASA Technical Reports Server (NTRS)

Eckardt, F. D.; Wilkinson, M. J.; Lulla, K. P.

2000-01-01

Digital terrain models are becoming increasingly available and are readily generated at a whole range of scales. However, the lack of realistic colour and tone in images of terrains remains a problem. Realistic colour and tone are very desirable attributes because they contribute significantly to a powerful visualization of landscapes, both for scientists (Kam's ref) and for the general public. But these attributes are generally still unavailable because few sensors, air- or space-borne, provide true colour, and even fewer do so at a realistic cost. The exception is the growing and accessible archive of US Space Shuttle photography which provides a wealth of potential data suited for more realistic visualization of landscapes.

[Digital signature: new prospects for the information of the cardiologic clinical card].

PubMed

Cervesato, E; Antonini-Canterin, F; Nicolosi, G L

2001-02-01

In the last few years, remarkable improvements have been made in computerized database systems used in cardiology. However, they will not easily lead to further relevant improvements unless the weaknesses and the gaps deriving from the obligation of forming and storing case sheets, according to law, are faced and resolved in an original way. This article covers the topic of the digital signature and how it could form the basis for a new powerful impulse to the process of informatization of cardiology records. The proposal of elaborating a totally computerized case sheet involves the need of rationalizing the flow of clinical information and of implementing a management system integrated with the hospital information system. The elimination of paper support will probably lead to an advantageous cycle that will involve the entire hospital, both clinically as well as administratively.

Digital cleaning and "dirt" layer visualization of an oil painting.

PubMed

Palomero, Cherry May T; Soriano, Maricor N

2011-10-10

We demonstrate a new digital cleaning technique which uses a neural network that is trained to learn the transformation from dirty to clean segments of a painting image. The inputs and outputs of the network are pixels belonging to dirty and clean segments found in Fernando Amorsolo's Malacañang by the River. After digital cleaning we visualize the painting's discoloration by assuming it to be a transmission filter superimposed on the clean painting. Using an RGB color-to-spectrum transformation to obtain the point-per-point spectra of the clean and dirty painting images, we calculate this "dirt" filter and render it for the whole image.

Image gathering and coding for digital restoration: Information efficiency and visual quality

NASA Technical Reports Server (NTRS)

Huck, Friedrich O.; John, Sarah; Mccormick, Judith A.; Narayanswamy, Ramkumar

1989-01-01

Image gathering and coding are commonly treated as tasks separate from each other and from the digital processing used to restore and enhance the images. The goal is to develop a method that allows us to assess quantitatively the combined performance of image gathering and coding for the digital restoration of images with high visual quality. Digital restoration is often interactive because visual quality depends on perceptual rather than mathematical considerations, and these considerations vary with the target, the application, and the observer. The approach is based on the theoretical treatment of image gathering as a communication channel (J. Opt. Soc. Am. A2, 1644(1985);5,285(1988). Initial results suggest that the practical upper limit of the information contained in the acquired image data range typically from approximately 2 to 4 binary information units (bifs) per sample, depending on the design of the image-gathering system. The associated information efficiency of the transmitted data (i.e., the ratio of information over data) ranges typically from approximately 0.3 to 0.5 bif per bit without coding to approximately 0.5 to 0.9 bif per bit with lossless predictive compression and Huffman coding. The visual quality that can be attained with interactive image restoration improves perceptibly as the available information increases to approximately 3 bifs per sample. However, the perceptual improvements that can be attained with further increases in information are very subtle and depend on the target and the desired enhancement.

Disaster relief through composite signatures

NASA Astrophysics Data System (ADS)

Hawley, Chadwick T.; Hyde, Brian; Carpenter, Tom; Nichols, Steve

2012-06-01

A composite signature is a group of signatures that are related in such a way to more completely or further define a target or operational endeavor at a higher fidelity. This paper builds on previous work developing innovative composite signatures associated with civil disasters, including physical, chemical and pattern/behavioral. For the composite signature approach to be successful it requires effective data fusion and visualization. This plays a key role in both preparedness and the response and recovery which are critical to saving lives. Visualization tools enhance the overall understanding of the crisis by pulling together and analyzing the data, and providing a clear and complete analysis of the information to the organizations/agencies dependant on it for a successful operation. An example of this, Freedom Web, is an easy-to-use data visualization and collaboration solution for use in homeland security, emergency preparedness, situational awareness, and event management. The solution provides a nationwide common operating picture for all levels of government through a web based, map interface. The tool was designed to be utilized by non-geospatial experts and is easily tailored to the specific needs of the users. Consisting of standard COTS and open source databases and a web server, users can view, edit, share, and highlight information easily and quickly through a standard internet browser.

VISUAL and SLOPE: perspective and quantitative representation of digital terrain models.

Treesearch

R.J. McGaughey; R.H. Twito

1988-01-01

Two computer programs to help timber-harvest planners evaluate terrain for logging operations are presented. The first program, VISUAL, produces three-dimensional perspectives of a digital terrain model. The second, SLOPE, produces map-scaled overlays delineating areas of equal slope, aspect, or elevation. Both programs help planners familiarize themselves with new...

A Web-Based Visualization and Animation Platform for Digital Logic Design

ERIC Educational Resources Information Center

Shoufan, Abdulhadi; Lu, Zheng; Huss, Sorin A.

2015-01-01

This paper presents a web-based education platform for the visualization and animation of the digital logic design process. This includes the design of combinatorial circuits using logic gates, multiplexers, decoders, and look-up-tables as well as the design of finite state machines. Various configurations of finite state machines can be selected…

Securing Digital Images Integrity using Artificial Neural Networks

NASA Astrophysics Data System (ADS)

Hajji, Tarik; Itahriouan, Zakaria; Ouazzani Jamil, Mohammed

2018-05-01

Digital image signature is a technique used to protect the image integrity. The application of this technique can serve several areas of imaging applied to smart cities. The objective of this work is to propose two methods to protect digital image integrity. We present a description of two approaches using artificial neural networks (ANN) to digitally sign an image. The first one is “Direct Signature without learning” and the second is “Direct Signature with learning”. This paper presents the theory of proposed approaches and an experimental study to test their effectiveness.

Signature Verification Using N-tuple Learning Machine.

PubMed

Maneechot, Thanin; Kitjaidure, Yuttana

2005-01-01

This research presents new algorithm for signature verification using N-tuple learning machine. The features are taken from handwritten signature on Digital Tablet (On-line). This research develops recognition algorithm using four features extraction, namely horizontal and vertical pen tip position(x-y position), pen tip pressure, and pen altitude angles. Verification uses N-tuple technique with Gaussian thresholding.

Digital Technology in the Visual Arts Classroom: An [un]Easy Partnership

ERIC Educational Resources Information Center

Wilks, Judith; Cutcher, Alexandra; Wilks, Susan

2012-01-01

This article scrutinizes the dichotomy of the uneasy and easy partnerships that exist between digital technology and visual arts education. The claim that by putting computers into schools "we have bought 'one half of a product'... we've bought the infrastructure and the equipment but we haven't bought the educational…

Identity-Based Verifiably Encrypted Signatures without Random Oracles

NASA Astrophysics Data System (ADS)

Zhang, Lei; Wu, Qianhong; Qin, Bo

Fair exchange protocol plays an important role in electronic commerce in the case of exchanging digital contracts. Verifiably encrypted signatures provide an optimistic solution to these scenarios with an off-line trusted third party. In this paper, we propose an identity-based verifiably encrypted signature scheme. The scheme is non-interactive to generate verifiably encrypted signatures and the resulting encrypted signature consists of only four group elements. Based on the computational Diffie-Hellman assumption, our scheme is proven secure without using random oracles. To the best of our knowledge, this is the first identity-based verifiably encrypted signature scheme provably secure in the standard model.

Visualization of permanent marks in progressive addition lenses by digital in-line holography

NASA Astrophysics Data System (ADS)

Perucho, Beatriz; Micó, Vicente

2013-04-01

A critical issue in the production of ophthalmic lenses is to guarantee the correct centering and alignment throughout the manufacturing and mounting processes. Aimed to that, progressive addition lenses (PALs) incorporate permanent marks at standardized locations at the lens. Those marks are engraved upon the surface and provide the model identification and addition power of the PAL, as well as to serve as locator marks to re-ink the removable marks again if necessary. Although the permanent marks should be visible by simple visual inspection, those marks are often faint and weak on new lenses providing low contrast, obscured by scratches on older lenses, and partially occluded and difficult to recognize on tinted or anti-reflection coated lenses. In this contribution, we present an extremely simple visualization system for permanent marks in PALs based on digital in-line holography. Light emitted by a superluminescent diode (SLD) is used to illuminate the PAL which is placed just before a digital (CCD) sensor. Thus, the CCD records an in-line hologram incoming from the diffracted wavefront provided by the PAL. As a result, it is possible to recover an in-focus image of the PAL inspected region by means of classical holographic tools applied in the digital domain. This numerical process involves digital recording of the in-line hologram, numerical back propagation to the PAL plane, and some digital processing to reduce noise and present a high quality final image. Preliminary experimental results are provided showing the applicability of the proposed method.

Visualized measurement of the acoustic levitation field based on digital holography with phase multiplication

NASA Astrophysics Data System (ADS)

Zheng, Puchao; Li, Enpu; Zhao, Jianlin; Di, Jianglei; Zhou, Wangmin; Wang, Hao; Zhang, Ruifeng

2009-11-01

By using digital holographic interferometory with phase multiplication, the visualized measurement of the acoustic levitation field (ALF) with single axis is carried out. The digital holograms of the ALF under different conditions are recorded by use of CCD. The corresponding digital holographic interferograms reflecting the sound pressure distribution and the interference phase distribution are obtained by numerical reconstruction and phase subtraction, which are consistent with the theoretical results. It indicates that the proposed digital holographic interferometory with phase multiplication can successfully double the fringe number of the interference phase patterns of the ALF and improve the measurement precision. Compared with the conventional optical holographic interferometory, digital holographic interferometory has the merits of quasi real-time, more exactitude and convenient operation, and it provides an effective way for studying the sound pressure distribution of the ALF.

Application of ultrasonic signature analysis for fatigue detection in complex structures

NASA Technical Reports Server (NTRS)

Zuckerwar, A. J.

1974-01-01

Ultrasonic signature analysis shows promise of being a singularly well-suited method for detecting fatigue in structures as complex as aircraft. The method employs instrumentation centered about a Fourier analyzer system, which features analog-to-digital conversion, digital data processing, and digital display of cross-correlation functions and cross-spectra. These features are essential to the analysis of ultrasonic signatures according to the procedure described here. In order to establish the feasibility of the method, the initial experiments were confined to simple plates with simulated and fatigue-induced defects respectively. In the first test the signature proved sensitive to the size of a small hole drilled into the plate. In the second test, performed on a series of fatigue-loaded plates, the signature proved capable of indicating both the initial appearance and subsequent growth of a fatigue crack. In view of these encouraging results it is concluded that the method has reached a sufficiently advanced stage of development to warrant application to small-scale structures or even actual aircraft.

Direct visualization of clay microfabric signatures driving organic matter preservation in fine-grained sediment

NASA Astrophysics Data System (ADS)

Curry, Kenneth J.; Bennett, Richard H.; Mayer, Lawrence M.; Curry, Ann; Abril, Maritza; Biesiot, Patricia M.; Hulbert, Matthew H.

2007-04-01

We employed direct visualization of organic matter (OM) sequestered by microfabric signatures in organo-clay systems to study mechanisms of OM protection. We studied polysaccharides, an abundant class of OM in marine sediments, associated with the nano- and microfabric of clay sediment using a novel application of transmission electron microscopy, histochemical staining (periodic acid-thiosemicarbazide-silver proteinate), and enzymatic digestion techniques. We used two experimental organo-clay sediment environments. First, laboratory-consolidated sediment with 10% chitin (w/w) added was probed for chitin before and after digestion with chitinase. Second, fecal pellets from the polychaete Heteromastus filiformis were used as a natural environment rich in clay and polysaccharides. Sections of this material were probed with silver proteinate for polysaccharides before and after digestion with a mixture of enzymes (amylase, cellulase, chitinase, dextranase, and pectinase). In both environments, chitin or other polysaccharides were found within pores, bridging clay domains, and attached to clay surfaces in undigested samples. Digested samples showed chitin or polysaccharides more closely associated with clay surfaces and in small pores. Our results imply protective roles for both sorption to clay surfaces and encapsulation within clay microfabric signatures.

Ballistic Signature Identification System Study

NASA Technical Reports Server (NTRS)

1976-01-01

The first phase of a research project directed toward development of a high speed automatic process to be used to match gun barrel signatures imparted to fired bullets was documented. An optical projection technique has been devised to produce and photograph a planar image of the entire signature, and the phototransparency produced is subjected to analysis using digital Fourier transform techniques. The success of this approach appears to be limited primarily by the accuracy of the photographic step since no significant processing limitations have been encountered.

Free-Space Quantum Signatures Using Heterodyne Measurements

NASA Astrophysics Data System (ADS)

Croal, Callum; Peuntinger, Christian; Heim, Bettina; Khan, Imran; Marquardt, Christoph; Leuchs, Gerd; Wallden, Petros; Andersson, Erika; Korolkova, Natalia

2016-09-01

Digital signatures guarantee the authorship of electronic communications. Currently used "classical" signature schemes rely on unproven computational assumptions for security, while quantum signatures rely only on the laws of quantum mechanics to sign a classical message. Previous quantum signature schemes have used unambiguous quantum measurements. Such measurements, however, sometimes give no result, reducing the efficiency of the protocol. Here, we instead use heterodyne detection, which always gives a result, although there is always some uncertainty. We experimentally demonstrate feasibility in a real environment by distributing signature states through a noisy 1.6 km free-space channel. Our results show that continuous-variable heterodyne detection improves the signature rate for this type of scheme and therefore represents an interesting direction in the search for practical quantum signature schemes. For transmission values ranging from 100% to 10%, but otherwise assuming an ideal implementation with no other imperfections, the signature length is shorter by a factor of 2 to 10. As compared with previous relevant experimental realizations, the signature length in this implementation is several orders of magnitude shorter.

Free-Space Quantum Signatures Using Heterodyne Measurements.

PubMed

Croal, Callum; Peuntinger, Christian; Heim, Bettina; Khan, Imran; Marquardt, Christoph; Leuchs, Gerd; Wallden, Petros; Andersson, Erika; Korolkova, Natalia

2016-09-02

Digital signatures guarantee the authorship of electronic communications. Currently used "classical" signature schemes rely on unproven computational assumptions for security, while quantum signatures rely only on the laws of quantum mechanics to sign a classical message. Previous quantum signature schemes have used unambiguous quantum measurements. Such measurements, however, sometimes give no result, reducing the efficiency of the protocol. Here, we instead use heterodyne detection, which always gives a result, although there is always some uncertainty. We experimentally demonstrate feasibility in a real environment by distributing signature states through a noisy 1.6 km free-space channel. Our results show that continuous-variable heterodyne detection improves the signature rate for this type of scheme and therefore represents an interesting direction in the search for practical quantum signature schemes. For transmission values ranging from 100% to 10%, but otherwise assuming an ideal implementation with no other imperfections, the signature length is shorter by a factor of 2 to 10. As compared with previous relevant experimental realizations, the signature length in this implementation is several orders of magnitude shorter.

Learning semantic and visual similarity for endomicroscopy video retrieval.

PubMed

Andre, Barbara; Vercauteren, Tom; Buchner, Anna M; Wallace, Michael B; Ayache, Nicholas

2012-06-01

Content-based image retrieval (CBIR) is a valuable computer vision technique which is increasingly being applied in the medical community for diagnosis support. However, traditional CBIR systems only deliver visual outputs, i.e., images having a similar appearance to the query, which is not directly interpretable by the physicians. Our objective is to provide a system for endomicroscopy video retrieval which delivers both visual and semantic outputs that are consistent with each other. In a previous study, we developed an adapted bag-of-visual-words method for endomicroscopy retrieval, called "Dense-Sift," that computes a visual signature for each video. In this paper, we present a novel approach to complement visual similarity learning with semantic knowledge extraction, in the field of in vivo endomicroscopy. We first leverage a semantic ground truth based on eight binary concepts, in order to transform these visual signatures into semantic signatures that reflect how much the presence of each semantic concept is expressed by the visual words describing the videos. Using cross-validation, we demonstrate that, in terms of semantic detection, our intuitive Fisher-based method transforming visual-word histograms into semantic estimations outperforms support vector machine (SVM) methods with statistical significance. In a second step, we propose to improve retrieval relevance by learning an adjusted similarity distance from a perceived similarity ground truth. As a result, our distance learning method allows to statistically improve the correlation with the perceived similarity. We also demonstrate that, in terms of perceived similarity, the recall performance of the semantic signatures is close to that of visual signatures and significantly better than those of several state-of-the-art CBIR methods. The semantic signatures are thus able to communicate high-level medical knowledge while being consistent with the low-level visual signatures and much shorter than them

Automatic removal of cosmic ray signatures in Deep Impact images

NASA Astrophysics Data System (ADS)

Ipatov, S. I.; A'Hearn, M. F.; Klaasen, K. P.

The results of recognition of cosmic ray (CR) signatures on single images made during the Deep Impact mission were analyzed for several codes written by several authors. For automatic removal of CR signatures on many images, we suggest using the code imgclean ( http://pdssbn.astro.umd.edu/volume/didoc_0001/document/calibration_software/dical_v5/) written by E. Deutsch as other codes considered do not work properly automatically with a large number of images and do not run to completion for some images; however, other codes can be better for analysis of certain specific images. Sometimes imgclean detects false CR signatures near the edge of a comet nucleus, and it often does not recognize all pixels of long CR signatures. Our code rmcr is the only code among those considered that allows one to work with raw images. For most visual images made during low solar activity at exposure time t > 4 s, the number of clusters of bright pixels on an image per second per sq. cm of CCD was about 2-4, both for dark and normal sky images. At high solar activity, it sometimes exceeded 10. The ratio of the number of CR signatures consisting of n pixels obtained at high solar activity to that at low solar activity was greater for greater n. The number of clusters detected as CR signatures on a single infrared image is by at least a factor of several greater than the actual number of CR signatures; the number of clusters based on analysis of two successive dark infrared frames is in agreement with an expected number of CR signatures. Some glitches of false CR signatures include bright pixels repeatedly present on different infrared images. Our interactive code imr allows a user to choose the regions on a considered image where glitches detected by imgclean as CR signatures are ignored. In other regions chosen by the user, the brightness of some pixels is replaced by the local median brightness if the brightness of these pixels is greater by some factor than the median brightness. The

Novel Perspectives on the Characterization of Species-Dependent Optical Signatures of Bacterial Colonies by Digital Holography.

PubMed

Buzalewicz, Igor; Kujawińska, Małgorzata; Krauze, Wojciech; Podbielska, Halina

2016-01-01

The use of light diffraction for the microbiological diagnosis of bacterial colonies was a significant breakthrough with widespread implications for the food industry and clinical practice. We previously confirmed that optical sensors for bacterial colony light diffraction can be used for bacterial identification. This paper is focused on the novel perspectives of this method based on digital in-line holography (DIH), which is able to reconstruct the amplitude and phase properties of examined objects, as well as the amplitude and phase patterns of the optical field scattered/diffracted by the bacterial colony in any chosen observation plane behind the object from single digital hologram. Analysis of the amplitude and phase patterns inside a colony revealed its unique optical properties, which are associated with the internal structure and geometry of the bacterial colony. Moreover, on a computational level, it is possible to select the desired scattered/diffracted pattern within the entire observation volume that exhibits the largest amount of unique, differentiating bacterial features. These properties distinguish this method from the already proposed sensing techniques based on light diffraction/scattering of bacterial colonies. The reconstructed diffraction patterns have a similar spatial distribution as the recorded Fresnel patterns, previously applied for bacterial identification with over 98% accuracy, but they are characterized by both intensity and phase distributions. Our results using digital holography provide new optical discriminators of bacterial species revealed in one single step in form of new optical signatures of bacterial colonies: digital holograms, reconstructed amplitude and phase patterns, as well as diffraction patterns from all observation space, which exhibit species-dependent features. To the best of our knowledge, this is the first report on bacterial colony analysis via digital holography and our study represents an innovative approach

Novel Perspectives on the Characterization of Species-Dependent Optical Signatures of Bacterial Colonies by Digital Holography

PubMed Central

Buzalewicz, Igor; Kujawińska, Małgorzata; Krauze, Wojciech; Podbielska, Halina

2016-01-01

The use of light diffraction for the microbiological diagnosis of bacterial colonies was a significant breakthrough with widespread implications for the food industry and clinical practice. We previously confirmed that optical sensors for bacterial colony light diffraction can be used for bacterial identification. This paper is focused on the novel perspectives of this method based on digital in-line holography (DIH), which is able to reconstruct the amplitude and phase properties of examined objects, as well as the amplitude and phase patterns of the optical field scattered/diffracted by the bacterial colony in any chosen observation plane behind the object from single digital hologram. Analysis of the amplitude and phase patterns inside a colony revealed its unique optical properties, which are associated with the internal structure and geometry of the bacterial colony. Moreover, on a computational level, it is possible to select the desired scattered/diffracted pattern within the entire observation volume that exhibits the largest amount of unique, differentiating bacterial features. These properties distinguish this method from the already proposed sensing techniques based on light diffraction/scattering of bacterial colonies. The reconstructed diffraction patterns have a similar spatial distribution as the recorded Fresnel patterns, previously applied for bacterial identification with over 98% accuracy, but they are characterized by both intensity and phase distributions. Our results using digital holography provide new optical discriminators of bacterial species revealed in one single step in form of new optical signatures of bacterial colonies: digital holograms, reconstructed amplitude and phase patterns, as well as diffraction patterns from all observation space, which exhibit species-dependent features. To the best of our knowledge, this is the first report on bacterial colony analysis via digital holography and our study represents an innovative approach

Perimetric Complexity of Binary Digital Images: Notes on Calculation and Relation to Visual Complexity

NASA Technical Reports Server (NTRS)

Watson, Andrew B.

2011-01-01

Perimetric complexity is a measure of the complexity of binary pictures. It is defined as the sum of inside and outside perimeters of the foreground, squared, divided by the foreground area, divided by 4p . Difficulties arise when this definition is applied to digital images composed of binary pixels. In this paper we identify these problems and propose solutions. Perimetric complexity is often used as a measure of visual complexity, in which case it should take into account the limited resolution of the visual system. We propose a measure of visual perimetric complexity that meets this requirement.

A Second Level Pictorial Turn? The Emergence of Digital Ekphrasis from The Visuality of New Media

ERIC Educational Resources Information Center

Shiel, Nina

2013-01-01

The increasing visuality of our culture was observed in 1994 by Mitchell, who coined the term "pictorial turn" to describe the interest in the visual taking place in culture and discourse (Mitchell, 1994). Since then, this process has increased further, particularly in all the areas of digital/new media. This chapter will consider this…

Theoretical Characterizaiton of Visual Signatures (Muzzle Flash)

NASA Astrophysics Data System (ADS)

Kashinski, D. O.; Scales, A. N.; Vanderley, D. L.; Chase, G. M.; di Nallo, O. E.; Byrd, E. F. C.

2014-05-01

We are investigating the accuracy of theoretical models used to predict the visible, ultraviolet and infrared spectra of product materials ejected from the muzzle of currently fielded systems. Recent advances in solid propellants has made the management of muzzle signature (flash) a principle issue in weapons development across the calibers. A priori prediction of the electromagnetic spectra of formulations will allow researchers to tailor blends that yield desired signatures and determine spectrographic detection ranges. We are currently employing quantum chemistry methods at various levels of sophistication to optimize molecular geometries, compute vibrational frequencies, and determine the optical spectra of specific gas-phase molecules and radicals of interest. Electronic excitations are being computed using Time Dependent Density Functional Theory (TD-DFT). A comparison of computational results to experimental values found in the literature is used to assess the affect of basis set and functional choice on calculation accuracy. The current status of this work will be presented at the conference. Work supported by the ARL, and USMA.

Image gathering and digital restoration for fidelity and visual quality

NASA Technical Reports Server (NTRS)

Huck, Friedrich O.; Alter-Gartenberg, Rachel; Rahman, Zia-Ur

1991-01-01

The fidelity and resolution of the traditional Wiener restorations given in the prevalent digital processing literature can be significantly improved when the transformations between the continuous and discrete representations in image gathering and display are accounted for. However, the visual quality of these improved restorations also is more sensitive to the defects caused by aliasing artifacts, colored noise, and ringing near sharp edges. In this paper, these visual defects are characterized, and methods for suppressing them are presented. It is demonstrated how the visual quality of fidelity-maximized images can be improved when (1) the image-gathering system is specifically designed to enhance the performance of the image-restoration algorithm, and (2) the Wiener filter is combined with interactive Gaussian smoothing, synthetic high edge enhancement, and nonlinear tone-scale transformation. The nonlinear transformation is used primarily to enhance the spatial details that are often obscurred when the normally wide dynamic range of natural radiance fields is compressed into the relatively narrow dynamic range of film and other displays.

Automatic cell identification and visualization using digital holographic microscopy with head mounted augmented reality devices.

PubMed

O'Connor, Timothy; Rawat, Siddharth; Markman, Adam; Javidi, Bahram

2018-03-01

We propose a compact imaging system that integrates an augmented reality head mounted device with digital holographic microscopy for automated cell identification and visualization. A shearing interferometer is used to produce holograms of biological cells, which are recorded using customized smart glasses containing an external camera. After image acquisition, segmentation is performed to isolate regions of interest containing biological cells in the field-of-view, followed by digital reconstruction of the cells, which is used to generate a three-dimensional (3D) pseudocolor optical path length profile. Morphological features are extracted from the cell's optical path length map, including mean optical path length, coefficient of variation, optical volume, projected area, projected area to optical volume ratio, cell skewness, and cell kurtosis. Classification is performed using the random forest classifier, support vector machines, and K-nearest neighbor, and the results are compared. Finally, the augmented reality device displays the cell's pseudocolor 3D rendering of its optical path length profile, extracted features, and the identified cell's type or class. The proposed system could allow a healthcare worker to quickly visualize cells using augmented reality smart glasses and extract the relevant information for rapid diagnosis. To the best of our knowledge, this is the first report on the integration of digital holographic microscopy with augmented reality devices for automated cell identification and visualization.

Holistic and Individualistic Evaluations of Digital Visual Art Portfolios: A Mixed Methods Study

ERIC Educational Resources Information Center

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…

Early ERP Signature of Hearing Impairment in Visual Rhyme Judgment

PubMed Central

Classon, Elisabet; Rudner, Mary; Johansson, Mikael; Rönnberg, Jerker

2013-01-01

Postlingually acquired hearing impairment (HI) is associated with changes in the representation of sound in semantic long-term memory. An indication of this is the lower performance on visual rhyme judgment tasks in conditions where phonological and orthographic cues mismatch, requiring high reliance on phonological representations. In this study, event-related potentials (ERPs) were used for the first time to investigate the neural correlates of phonological processing in visual rhyme judgments in participants with acquired HI and normal hearing (NH). Rhyme task word pairs rhymed or not and had matching or mismatching orthography. In addition, the inter-stimulus interval (ISI) was manipulated to be either long (800 ms) or short (50 ms). Long ISIs allow for engagement of explicit, top-down processes, while short ISIs limit the involvement of such mechanisms. We hypothesized lower behavioral performance and N400 and N2 deviations in HI in the mismatching rhyme judgment conditions, particularly in short ISI. However, the results showed a different pattern. As expected, behavioral performance in the mismatch conditions was lower in HI than in NH in short ISI, but ERPs did not differ across groups. In contrast, HI performed on a par with NH in long ISI. Further, HI, but not NH, showed an amplified N2-like response in the non-rhyming, orthographically mismatching condition in long ISI. This was also the rhyme condition in which participants in both groups benefited the most from the possibility to engage top-down processes afforded with the longer ISI. Taken together, these results indicate an early ERP signature of HI in this challenging phonological task, likely reflecting use of a compensatory strategy. This strategy is suggested to involve increased reliance on explicit mechanisms such as articulatory recoding and grapheme-to-phoneme conversion. PMID:23653613

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

PubMed

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.

In Internet-Based Visualization System Study about Breakthrough Applet Security Restrictions

NASA Astrophysics Data System (ADS)

Chen, Jie; Huang, Yan

In the process of realization Internet-based visualization system of the protein molecules, system needs to allow users to use the system to observe the molecular structure of the local computer, that is, customers can generate the three-dimensional graphics from PDB file on the client computer. This requires Applet access to local file, related to the Applet security restrictions question. In this paper include two realization methods: 1.Use such as signature tools, key management tools and Policy Editor tools provided by the JDK to digital signature and authentication for Java Applet, breakthrough certain security restrictions in the browser. 2. Through the use of Servlet agent implement indirect access data methods, breakthrough the traditional Java Virtual Machine sandbox model restriction of Applet ability. The two ways can break through the Applet's security restrictions, but each has its own strengths.

Driving without wings: The effect of different digital mirror locations on the visual behaviour, performance and opinions of drivers.

PubMed

Large, David R; Crundall, Elizabeth; Burnett, Gary; Harvey, Catherine; Konstantopoulos, Panos

2016-07-01

Drivers' awareness of the rearward road scene is critical when contemplating or executing lane-change manoeuvres, such as overtaking. Preliminary investigations have speculated on the use of rear-facing cameras to relay images to displays mounted inside the car to create 'digital mirrors'. These may overcome many of the limitations associated with traditional 'wing' and rear-view mirrors, yet will inevitably effect drivers' normal visual scanning behaviour, and may force them to consider the rearward road scene from an unfamiliar perspective that is incongruent with their mental model of the outside world. We describe a study conducted within a medium-fidelity simulator aiming to explore the visual behaviour, driving performance and opinions of drivers while using internally located digital mirrors during different overtaking manoeuvres. Using a generic UK motorway scenario, thirty-eight experienced drivers conducted overtaking manoeuvres using each of five different layouts of digital mirrors with varying degrees of 'real-world' mapping. The results showed reductions in decision time for lane changes and eyes-off road time while using the digital mirrors, when compared with baseline traditional reflective mirrors, suggesting that digital displays may enable drivers to more rapidly pick up the salient information from the rearward road scene. Subjectively, drivers preferred configurations that most closely matched existing mirror locations, where aspects of real-world mapping were largely preserved. The research highlights important human factors issues that require further investigation prior to further development/implementation of digital mirrors within vehicles. Future work should also aim to validate findings within real-world on-road environments whilst considering the effects of digital mirrors on other important visual behaviour characteristics, such as depth perception. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Improved visualization of intracranial vessels with intraoperative coregistration of rotational digital subtraction angiography and intraoperative 3D ultrasound.

PubMed

Podlesek, Dino; Meyer, Tobias; Morgenstern, Ute; Schackert, Gabriele; Kirsch, Matthias

2015-01-01

Ultrasound can visualize and update the vessel status in real time during cerebral vascular surgery. We studied the depiction of parent vessels and aneurysms with a high-resolution 3D intraoperative ultrasound imaging system during aneurysm clipping using rotational digital subtraction angiography as a reference. We analyzed 3D intraoperative ultrasound in 39 patients with cerebral aneurysms to visualize the aneurysm intraoperatively and the nearby vascular tree before and after clipping. Simultaneous coregistration of preoperative subtraction angiography data with 3D intraoperative ultrasound was performed to verify the anatomical assignment. Intraoperative ultrasound detected 35 of 43 aneurysms (81%) in 39 patients. Thirty-nine intraoperative ultrasound measurements were matched with rotational digital subtraction angiography and were successfully reconstructed during the procedure. In 7 patients, the aneurysm was partially visualized by 3D-ioUS or was not in field of view. Post-clipping intraoperative ultrasound was obtained in 26 and successfully reconstructed in 18 patients (69%) despite clip related artefacts. The overlap between 3D-ioUS aneurysm volume and preoperative rDSA aneurysm volume resulted in a mean accuracy of 0.71 (Dice coefficient). Intraoperative coregistration of 3D intraoperative ultrasound data with preoperative rotational digital subtraction angiography is possible with high accuracy. It allows the immediate visualization of vessels beyond the microscopic field, as well as parallel assessment of blood velocity, aneurysm and vascular tree configuration. Although spatial resolution is lower than for standard angiography, the method provides an excellent vascular overview, advantageous interpretation of 3D-ioUS and immediate intraoperative feedback of the vascular status. A prerequisite for understanding vascular intraoperative ultrasound is image quality and a successful match with preoperative rotational digital subtraction angiography.

Taking the world for a spin: teaching spatial and data visualization with a digital globe

NASA Astrophysics Data System (ADS)

Teplitzky, S.; Powell, S.

2016-12-01

In the summer of 2016, the Earth Sciences & Map Library at the University of California, Berkeley, purchased a Magic Planet digital globe in a collaboration between the library and the departments of Geography and Earth & Planetary Science. This 30" diameter 3D display supplements and expands the library's instruction and outreach activities in GIS, data visualization and modeling. Faculty and graduate students were surveyed regarding their interest in using the globe for teaching and research projects. Based on this feedback, librarians developed a basic training plan for using the globe in the classroom, as well as an assessment tool to rate the effectiveness of instruction with the digital globe. Student and faculty responses at the end of fall semester (2016) will be evaluated for future plans to increase the variety of data sets and animations available to view on the globe. Curriculum and guides for visualizing custom and interactive data sets will be developed and made available based on current researcher and student interests. We are excited about partnering with our departments and engaging our students in the possibilities of 3d visualization, and look forward to sharing lessons learned.

A Situated Practice of Ethics for Participatory Visual and Digital Methods in Public Health Research and Practice: A Focus on Digital Storytelling

PubMed Central

Hill, Amy L.; Flicker, Sarah

2014-01-01

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. PMID:23948015

Digital camera with apparatus for authentication of images produced from an image file

NASA Technical Reports Server (NTRS)

Friedman, Gary L. (Inventor)

1993-01-01

A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely based upon the private key that digital data encrypted with the private key by the processor may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating at any time the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match, since even one bit change in the image hash will cause the image hash to be totally different from the secure hash.

Digital Camera with Apparatus for Authentication of Images Produced from an Image File

NASA Technical Reports Server (NTRS)

Friedman, Gary L. (Inventor)

1996-01-01

A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely related to the private key that digital data encrypted with the private key may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The authenticating apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match. Other techniques to address time-honored methods of deception, such as attaching false captions or inducing forced perspectives, are included.

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

ERIC Educational Resources Information Center

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…

Digital image envelope: method and evaluation

NASA Astrophysics Data System (ADS)

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.

A copyright protection scheme for digital images based on shuffled singular value decomposition and visual cryptography.

PubMed

Devi, B Pushpa; Singh, Kh Manglem; Roy, Sudipta

2016-01-01

This paper proposes a new watermarking algorithm based on the shuffled singular value decomposition and the visual cryptography for copyright protection of digital images. It generates the ownership and identification shares of the image based on visual cryptography. It decomposes the image into low and high frequency sub-bands. The low frequency sub-band is further divided into blocks of same size after shuffling it and then the singular value decomposition is applied to each randomly selected block. Shares are generated by comparing one of the elements in the first column of the left orthogonal matrix with its corresponding element in the right orthogonal matrix of the singular value decomposition of the block of the low frequency sub-band. The experimental results show that the proposed scheme clearly verifies the copyright of the digital images, and is robust to withstand several image processing attacks. Comparison with the other related visual cryptography-based algorithms reveals that the proposed method gives better performance. The proposed method is especially resilient against the rotation attack.

Using digital photo technology to improve visualization of gastric lumen CT images

NASA Astrophysics Data System (ADS)

Pyrgioti, M.; Kyriakidis, A.; Chrysostomou, S.; Panaritis, V.

2006-12-01

In order to evaluate the gastric lumen CT images better, a new method is being applied to images using an Image Processing software. During a 12-month period, 69 patients with various gastric symptoms and 20 normal (as far as it concerns the upper gastrointestinal system) volunteers underwent computed tomography of the upper gastrointestinal system. Just before the examination the patients and the normal volunteers underwent preparation with 40 ml soda water and 10 ml gastrografin. All the CT images were digitized with an Olympus 3.2 Mpixel digital camera and further processed with an Image Processing software. The administration per os of gastrografin and soda water resulted in the distension of the stomach and consequently better visualization of all the anatomic parts. By using an Image Processing software in a PC, all the pathological and normal images of the stomach were better diagnostically estimated. We believe that the photo digital technology improves the diagnostic capacity not only of the CT image but also in MRI and probably many other imaging methods.

Clinical and cognitive correlates of visual hallucinations in dementia with Lewy bodies.

PubMed

Cagnin, Annachiara; Gnoato, Francesca; Jelcic, Nela; Favaretto, Silvia; Zarantonello, Giulia; Ermani, Mario; Dam, Mauro

2013-05-01

The presence of recurrent complex visual hallucinations (VHs) is a core feature of dementia with Lewy bodies (DLB). The aim of this study was to investigate which clinical and neuropsychological characteristics are associated with VHs and their predictive value over a 1 year follow-up. 81 DLB patients, 41 with (VH+) and 36 without (VH-) VHs, and 45 patients with Alzheimer's disease (AD), were enrolled. All participants underwent extensive neuropsychological testing. Visual-spatial and perceptual abilities were evaluated with the Visual and Object Space Perception (VOSP) battery. Fluctuations in attention, rapid eye movement sleep behaviour disorder (RBD) symptoms, extrapyramidal signs and behavioural disturbances were studied with dedicated clinical scales. The presence of VHs was associated with older age and later disease onset, but not with disease duration or with fluctuations, RBD or parkinsonism severity. Cognitive correlates of VHs were deficits in visual attention (digit cancellation: p<0.005) and executive functions (clock drawing: p<0.05; digit span forward: p<0.05) on a background of a slightly worse global cognitive performance (Mini-Mental State Examination: p=0.05). Visual-perceptual and visual-spatial deficits were significantly worse in DLB than in AD patients (VOSP subtests scores 1, 6, 7 and 8) but were not different in DLB VH+ and VH-, except for subtest 6. Poor performance in the visual attention task was an independent predictor of VHs. Impairment of visual-spatial and perceptual abilities in DLB represents a disease related cognitive signature, independent of the presence of VHs, for which it may represent a predisposing condition. Visual attention, instead, is the main cognitive determinant for the genesis of VHs.

Improved Visualization of Intracranial Vessels with Intraoperative Coregistration of Rotational Digital Subtraction Angiography and Intraoperative 3D Ultrasound

PubMed Central

Podlesek, Dino; Meyer, Tobias; Morgenstern, Ute; Schackert, Gabriele; Kirsch, Matthias

2015-01-01

Introduction Ultrasound can visualize and update the vessel status in real time during cerebral vascular surgery. We studied the depiction of parent vessels and aneurysms with a high-resolution 3D intraoperative ultrasound imaging system during aneurysm clipping using rotational digital subtraction angiography as a reference. Methods We analyzed 3D intraoperative ultrasound in 39 patients with cerebral aneurysms to visualize the aneurysm intraoperatively and the nearby vascular tree before and after clipping. Simultaneous coregistration of preoperative subtraction angiography data with 3D intraoperative ultrasound was performed to verify the anatomical assignment. Results Intraoperative ultrasound detected 35 of 43 aneurysms (81%) in 39 patients. Thirty-nine intraoperative ultrasound measurements were matched with rotational digital subtraction angiography and were successfully reconstructed during the procedure. In 7 patients, the aneurysm was partially visualized by 3D-ioUS or was not in field of view. Post-clipping intraoperative ultrasound was obtained in 26 and successfully reconstructed in 18 patients (69%) despite clip related artefacts. The overlap between 3D-ioUS aneurysm volume and preoperative rDSA aneurysm volume resulted in a mean accuracy of 0.71 (Dice coefficient). Conclusions Intraoperative coregistration of 3D intraoperative ultrasound data with preoperative rotational digital subtraction angiography is possible with high accuracy. It allows the immediate visualization of vessels beyond the microscopic field, as well as parallel assessment of blood velocity, aneurysm and vascular tree configuration. Although spatial resolution is lower than for standard angiography, the method provides an excellent vascular overview, advantageous interpretation of 3D-ioUS and immediate intraoperative feedback of the vascular status. A prerequisite for understanding vascular intraoperative ultrasound is image quality and a successful match with preoperative

Age discrimination among basalt flows using digitally enhanced LANDSAT imagery. [Saudi Arabia

NASA Technical Reports Server (NTRS)

Blodget, H. W.; Brown, G. F.

1984-01-01

Digitally enhanced LANDSAT MSS data were used to discriminate among basalt flows of historical to Tertiary age, at a test site in Northwestern Saudi Arabia. Spectral signatures compared favorably with a field-defined classification that permits discrimination among five groups of basalt flows on the basis of geomorphic criteria. Characteristics that contributed to age definition include: surface texture, weathering, color, drainage evolution, and khabrah development. The inherent gradation in the evolution of geomorphic parameters, however, makes visual extrapolation between areas subjective. Therefore, incorporation of spectrally-derived volcanic units into the mapping process should produce more quantitatively consistent age groupings.

Signature simulation of mixed materials

NASA Astrophysics Data System (ADS)

Carson, Tyler D.; Salvaggio, Carl

2015-05-01

Soil target signatures vary due to geometry, chemical composition, and scene radiometry. Although radiative transfer models and function-fit physical models may describe certain targets in limited depth, the ability to incorporate all three signature variables is difficult. This work describes a method to simulate the transient signatures of soil by first considering scene geometry synthetically created using 3D physics engines. Through the assignment of spectral data from the Nonconventional Exploitation Factors Data System (NEFDS), the synthetic scene is represented as a physical mixture of particles. Finally, first principles radiometry is modeled using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model. With DIRSIG, radiometric and sensing conditions were systematically manipulated to produce and record goniometric signatures. The implementation of this virtual goniometer allows users to examine how a target bidirectional reflectance distribution function (BRDF) will change with geometry, composition, and illumination direction. By using 3D computer graphics models, this process does not require geometric assumptions that are native to many radiative transfer models. It delivers a discrete method to circumnavigate the significant cost of time and treasure associated with hardware-based goniometric data collections.

Rapid Processing of Letters, Digits and Symbols: What Purely Visual-Attentional Deficit in Developmental Dyslexia?

ERIC Educational Resources Information Center

Ziegler, Johannes C.; Pech-Georgel, Catherine; Dufau, Stephane; Grainger, Jonathan

2010-01-01

Visual-attentional theories of dyslexia predict deficits for dyslexic children not only for the perception of letter strings but also for non-alphanumeric symbol strings. This prediction was tested in a two-alternative forced-choice paradigm with letters, digits, and symbols. Children with dyslexia showed significant deficits for letter and digit…

Learning about the scale of the solar system using digital planetarium visualizations

NASA Astrophysics Data System (ADS)

Yu, Ka Chun; Sahami, Kamran; Dove, James

2017-07-01

We studied the use of a digital planetarium for teaching relative distances and sizes in introductory undergraduate astronomy classes. Inspired in part by the classic short film The Powers of Ten and large physical scale models of the Solar System that can be explored on foot, we created lectures using virtual versions of these two pedagogical approaches for classes that saw either an immersive treatment in the planetarium or a non-immersive version in the regular classroom (with N = 973 students participating in total). Students who visited the planetarium had not only the greatest learning gains, but their performance increased with time, whereas students who saw the same visuals projected onto a flat display in their classroom showed less retention over time. The gains seen in the students who visited the planetarium reveal that this medium is a powerful tool for visualizing scale over multiple orders of magnitude. However the modest gains for the students in the regular classroom also show the utility of these visualization approaches for the broader category of classroom physics simulations.

[Digital administrative maps - a tool for visualization of epidemiological data].

PubMed

Niewiadomska, Ewa; Kowalska, Malgorzata; Czech, Elibieta; Skrzypek, Michal

2013-01-01

The aim of the study is to present the methods for visualization of epidemiological data using digital contour maps that take into account administrative division of Poland. The possibility of epidemiological data visualization in a geographical order, limited to the administrative level of the country, voivodeships and poviats (countics), are presented. They are crucial for the process of identifying and undertaking adequate prophylactic activities directed towards decreasing the risk and improving the population's health. This paper presents tools and techniques available in Geographic Information System ArcGIS and statistical software package R. The work includes our own data reflecting: 1) the values of specific mortality rates due to respiratory diseases, Poland, 2010, based on the Central Statistical Office data, using the R statistical software package; 2) the averaged registered incidence rates of sarcoidosis in 2006-2010 for the population aged 19+ in the Silesian voivodeship, using G(eographic Information System ArcGIS; and 3) the number of children with diagnosed respiratory diseases in the city of L.egnica in 2009, taking into account their place of residence, using layered maps in Geographic Information System ArcGIS. The tools presented and described in this paper make it possible to visualize the results of research, to increase attractiveness of courses for students, as well as to enhance the skills and competence of students and participants of courses.

Examples of challenges and opportunities in visual analysis in the digital humanities

NASA Astrophysics Data System (ADS)

Rushmeier, Holly; Pintus, Ruggero; Yang, Ying; Wong, Christiana; Li, David

2015-03-01

The massive digitization of books and manuscripts has converted millions of works that were once only physical into electronic documents. This conversion has made it possible for scholars to study large bodies of work, rather than just individual texts. This has offered new opportunities for scholarship in the humanities. Much previous work on digital collections has relied on optical character recognition and focused on the textual content of books. New work is emerging that is analyzing the visual layout and content of books and manuscripts. We present two different digital humanities projects in progress that present new opportunities for extracting data about the past, with new challenges for designing systems for scholars to interact with this data. The first project we consider is the layout and spectral content of thousands of pages from medieval manuscripts. We present the techniques used to study content variations in sets of similar manuscripts, and to study material variations that may indicate the location of manuscript production. The second project is the analysis of representations in the complete archive of Vogue magazine over 120 years. We present samples of applying computer vision techniques to understanding the changes in representation of women over time.

The forensic validity of visual analytics

NASA Astrophysics Data System (ADS)

Erbacher, Robert F.

2008-01-01

The wider use of visualization and visual analytics in wide ranging fields has led to the need for visual analytics capabilities to be legally admissible, especially when applied to digital forensics. This brings the need to consider legal implications when performing visual analytics, an issue not traditionally examined in visualization and visual analytics techniques and research. While digital data is generally admissible under the Federal Rules of Evidence [10][21], a comprehensive validation of the digital evidence is considered prudent. A comprehensive validation requires validation of the digital data under rules for authentication, hearsay, best evidence rule, and privilege. Additional issues with digital data arise when exploring digital data related to admissibility and the validity of what information was examined, to what extent, and whether the analysis process was sufficiently covered by a search warrant. For instance, a search warrant generally covers very narrow requirements as to what law enforcement is allowed to examine and acquire during an investigation. When searching a hard drive for child pornography, how admissible is evidence of an unrelated crime, i.e. drug dealing. This is further complicated by the concept of "in plain view". When performing an analysis of a hard drive what would be considered "in plain view" when analyzing a hard drive. The purpose of this paper is to discuss the issues of digital forensics and the related issues as they apply to visual analytics and identify how visual analytics techniques fit into the digital forensics analysis process, how visual analytics techniques can improve the legal admissibility of digital data, and identify what research is needed to further improve this process. The goal of this paper is to open up consideration of legal ramifications among the visualization community; the author is not a lawyer and the discussions are not meant to be inclusive of all differences in laws between states and

Visual and Statistical Analysis of Digital Elevation Models Generated Using Idw Interpolator with Varying Powers

NASA Astrophysics Data System (ADS)

Asal, F. F.

2012-07-01

Digital elevation data obtained from different Engineering Surveying techniques is utilized in generating Digital Elevation Model (DEM), which is employed in many Engineering and Environmental applications. This data is usually in discrete point format making it necessary to utilize an interpolation approach for the creation of DEM. Quality assessment of the DEM is a vital issue controlling its use in different applications; however this assessment relies heavily on statistical methods with neglecting the visual methods. The research applies visual analysis investigation on DEMs generated using IDW interpolator of varying powers in order to examine their potential in the assessment of the effects of the variation of the IDW power on the quality of the DEMs. Real elevation data has been collected from field using total station instrument in a corrugated terrain. DEMs have been generated from the data at a unified cell size using IDW interpolator with power values ranging from one to ten. Visual analysis has been undertaken using 2D and 3D views of the DEM; in addition, statistical analysis has been performed for assessment of the validity of the visual techniques in doing such analysis. Visual analysis has shown that smoothing of the DEM decreases with the increase in the power value till the power of four; however, increasing the power more than four does not leave noticeable changes on 2D and 3D views of the DEM. The statistical analysis has supported these results where the value of the Standard Deviation (SD) of the DEM has increased with increasing the power. More specifically, changing the power from one to two has produced 36% of the total increase (the increase in SD due to changing the power from one to ten) in SD and changing to the powers of three and four has given 60% and 75% respectively. This refers to decrease in DEM smoothing with the increase in the power of the IDW. The study also has shown that applying visual methods supported by statistical

Experiences of Students with Visual Impairments in Adoption of Digital Talking Textbooks: An Interpretative Phenomenological Analysis

ERIC Educational Resources Information Center

Hussin, Ahamad; Folkestad, James E.; Makela, Carole

2013-01-01

This study was conducted to explore the experiences of Malaysian secondary students with visual impairments in using digital talking textbooks (DTTs) to assist their learning. Data were obtained from individual in-depth interviews. An interpretative phenomenological analysis (IPA) was used to understand the findings and confirm the emergent…

Experiences of Students with Visual Impairments in Adoption of Digital Talking Textbooks: An Interpretative Phenomenological Analysis

ERIC Educational Resources Information Center

Hussin, Ahamad

2013-01-01

Assistive technology devices have become essential tools for students with visual impairments. In 2009, the Malaysian Ministry of Education introduced Digital Talking Textbooks (DTTs) for selected subjects to facilitate learning. The purpose of this qualitative study was to explore, describe, and interpret the experiences of students with visual…

Digital Image Access & Retrieval.

ERIC Educational Resources Information Center

Heidorn, P. Bryan, Ed.; Sandore, Beth, Ed.

Recent technological advances in computing and digital imaging technology have had immediate and permanent consequences for visual resource collections. Libraries are involved in organizing and managing large visual resource collections. The central challenges in working with digital image collections mirror those that libraries have sought to…

Accuracy and Feasibility of an Android-Based Digital Assessment Tool for Post Stroke Visual Disorders-The StrokeVision App.

PubMed

Quinn, Terence J; Livingstone, Iain; Weir, Alexander; Shaw, Robert; Breckenridge, Andrew; McAlpine, Christine; Tarbert, Claire M

2018-01-01

Visual impairment affects up to 70% of stroke survivors. We designed an app (StrokeVision) to facilitate screening for common post stroke visual issues (acuity, visual fields, and visual inattention). We sought to describe the test time, feasibility, acceptability, and accuracy of our app-based digital visual assessments against (a) current methods used for bedside screening and (b) gold standard measures. Patients were prospectively recruited from acute stroke settings. Index tests were app-based assessments of fields and inattention performed by a trained researcher. We compared against usual clinical screening practice of visual fields to confrontation, including inattention assessment (simultaneous stimuli). We also compared app to gold standard assessments of formal kinetic perimetry (Goldman or Octopus Visual Field Assessment); and pencil and paper-based tests of inattention (Albert's, Star Cancelation, and Line Bisection). Results of inattention and field tests were adjudicated by a specialist Neuro-ophthalmologist. All assessors were masked to each other's results. Participants and assessors graded acceptability using a bespoke scale that ranged from 0 (completely unacceptable) to 10 (perfect acceptability). Of 48 stroke survivors recruited, the complete battery of index and reference tests for fields was successfully completed in 45. Similar acceptability scores were observed for app-based [assessor median score 10 (IQR: 9-10); patient 9 (IQR: 8-10)] and traditional bedside testing [assessor 10 (IQR: 9-10); patient 10 (IQR: 9-10)]. Median test time was longer for app-based testing [combined time to completion of all digital tests 420 s (IQR: 390-588)] when compared with conventional bedside testing [70 s, (IQR: 40-70)], but shorter than gold standard testing [1,260 s, (IQR: 1005-1,620)]. Compared with gold standard assessments, usual screening practice demonstrated 79% sensitivity and 82% specificity for detection of a stroke-related field defect

Study of Dynamic Characteristics of Aeroelastic Systems Utilizing Randomdec Signatures

NASA Technical Reports Server (NTRS)

Chang, C. S.

1975-01-01

The feasibility of utilizing the random decrement method in conjunction with a signature analysis procedure to determine the dynamic characteristics of an aeroelastic system for the purpose of on-line prediction of potential on-set of flutter was examined. Digital computer programs were developed to simulate sampled response signals of a two-mode aeroelastic system. Simulated response data were used to test the random decrement method. A special curve-fit approach was developed for analyzing the resulting signatures. A number of numerical 'experiments' were conducted on the combined processes. The method is capable of determining frequency and damping values accurately from randomdec signatures of carefully selected lengths.

Kinematics of Signature Writing in Healthy Aging*

PubMed Central

Caligiuri, Michael P.; Kim, Chi; Landy, Kelly M.

2014-01-01

Forensic document examiners (FDE) called upon to distinguish a genuine from a forged signature of an elderly person are often required to consider the question of age-related deterioration and whether the available exemplars reliably capture the natural effects of aging of the original writer. An understanding of the statistical relationship between advanced age and handwriting movements can reduce the uncertainty that may exist in an examiner’s approach to questioned signatures formed by elderly writers. The primary purpose of this study was to systematically examine age-related changes in signature kinematics in healthy writers. Forty-two healthy subjects between the ages of 60–91 years participated in this study. Signatures were recorded using a digitizing tablet and commercial software was used to examine the temporal and spatial stroke kinematics and pen pressure. Results indicated that vertical stroke duration and dysfluency increased with age, whereas vertical stroke amplitude and velocity decreased with age. Pen pressure decreased with age. We found that a linear model characterized the best-fit relationship between advanced age and handwriting movement parameters for signature formation. Male writers exhibited stronger age effects than female writers, especially for pen pressure and stroke dysfluency. The present study contributes to an understanding of how advanced age alters signature formation in otherwise healthy adults. PMID:24673648

A malaria diagnostic tool based on computer vision screening and visualization of Plasmodium falciparum candidate areas in digitized blood smears.

PubMed

Linder, Nina; Turkki, Riku; Walliander, Margarita; Mårtensson, Andreas; Diwan, Vinod; Rahtu, Esa; Pietikäinen, Matti; Lundin, Mikael; Lundin, Johan

2014-01-01

Microscopy is the gold standard for diagnosis of malaria, however, manual evaluation of blood films is highly dependent on skilled personnel in a time-consuming, error-prone and repetitive process. In this study we propose a method using computer vision detection and visualization of only the diagnostically most relevant sample regions in digitized blood smears. Giemsa-stained thin blood films with P. falciparum ring-stage trophozoites (n = 27) and uninfected controls (n = 20) were digitally scanned with an oil immersion objective (0.1 µm/pixel) to capture approximately 50,000 erythrocytes per sample. Parasite candidate regions were identified based on color and object size, followed by extraction of image features (local binary patterns, local contrast and Scale-invariant feature transform descriptors) used as input to a support vector machine classifier. The classifier was trained on digital slides from ten patients and validated on six samples. The diagnostic accuracy was tested on 31 samples (19 infected and 12 controls). From each digitized area of a blood smear, a panel with the 128 most probable parasite candidate regions was generated. Two expert microscopists were asked to visually inspect the panel on a tablet computer and to judge whether the patient was infected with P. falciparum. The method achieved a diagnostic sensitivity and specificity of 95% and 100% as well as 90% and 100% for the two readers respectively using the diagnostic tool. Parasitemia was separately calculated by the automated system and the correlation coefficient between manual and automated parasitemia counts was 0.97. We developed a decision support system for detecting malaria parasites using a computer vision algorithm combined with visualization of sample areas with the highest probability of malaria infection. The system provides a novel method for blood smear screening with a significantly reduced need for visual examination and has a potential to increase the

Identification of crops in Central Arkansas using visual and infrared spectral reflectance signatures

NASA Technical Reports Server (NTRS)

1977-01-01

The spectral reflectance signatures of principle crops of central Arkansas were calibrated. Data were collected by conducting ground based reflectance signatures at well controlled test sites. Data collected were primarily for soybeans, therefore, additional measurements are essential to the acquisition of significant results.

iPixel: a visual content-based and semantic search engine for retrieving digitized mammograms by using collective intelligence.

PubMed

Alor-Hernández, Giner; Pérez-Gallardo, Yuliana; Posada-Gómez, Rubén; Cortes-Robles, Guillermo; Rodríguez-González, Alejandro; Aguilar-Laserre, Alberto A

2012-09-01

Nowadays, traditional search engines such as Google, Yahoo and Bing facilitate the retrieval of information in the format of images, but the results are not always useful for the users. This is mainly due to two problems: (1) the semantic keywords are not taken into consideration and (2) it is not always possible to establish a query using the image features. This issue has been covered in different domains in order to develop content-based image retrieval (CBIR) systems. The expert community has focussed their attention on the healthcare domain, where a lot of visual information for medical analysis is available. This paper provides a solution called iPixel Visual Search Engine, which involves semantics and content issues in order to search for digitized mammograms. iPixel offers the possibility of retrieving mammogram features using collective intelligence and implementing a CBIR algorithm. Our proposal compares not only features with similar semantic meaning, but also visual features. In this sense, the comparisons are made in different ways: by the number of regions per image, by maximum and minimum size of regions per image and by average intensity level of each region. iPixel Visual Search Engine supports the medical community in differential diagnoses related to the diseases of the breast. The iPixel Visual Search Engine has been validated by experts in the healthcare domain, such as radiologists, in addition to experts in digital image analysis.

Secure quantum signatures: a practical quantum technology (Conference Presentation)

NASA Astrophysics Data System (ADS)

Andersson, Erika

2016-10-01

Modern cryptography encompasses much more than encryption of secret messages. Signature schemes are widely used to guarantee that messages cannot be forged or tampered with, for example in e-mail, software updates and electronic commerce. Messages are also transferrable, which distinguishes digital signatures from message authentication. Transferability means that messages can be forwarded; in other words, that a sender is unlikely to be able to make one recipient accept a message which is subsequently rejected by another recipient if the message is forwarded. Similar to public-key encryption, the security of commonly used signature schemes relies on the assumed computational difficulty of problems such as finding discrete logarithms or factoring large primes. With quantum computers, such assumptions would no longer be valid. Partly for this reason, it is desirable to develop signature schemes with unconditional or information-theoretic security. Quantum signature schemes are one possible solution. Similar to quantum key distribution (QKD), their unconditional security relies only on the laws of quantum mechanics. Quantum signatures can be realized with the same system components as QKD, but are so far less investigated. This talk aims to provide an introduction to quantum signatures and to review theoretical and experimental progress so far.

The Effects of Visual Illustrations on Learners' Achievement and Interest in PDA- (Personal Digital Assistant) Based Learning

ERIC Educational Resources Information Center

Park, Sanghoon; Kim, Minjeong; Lee, Youngmin; Son, Chanhee; Lee, Miyoung

2005-01-01

PDAs (Personal Digital Assistants) have been used widely in educational settings. In this study, the visual illustration of a scientific text (cognitive-interest illustration, emotional-interest illustration, or no illustration) was manipulated to investigate its impact on student interest in instructional materials, achievement, and time spent on…

Changes in the Management of Information in Audio-Visual Archives following Digitization: Current and Future Outlook

ERIC Educational Resources Information Center

Caldera-Serrano, Jorge

2008-01-01

This article attempts to offer an overview of the current changes that are being experienced in the management of audio-visual documentation and those that can be forecast in the future as a result of the migration from analogue to digital information. For this purpose the documentary chain will be used as a basis to analyse individually the tasks…

[Constructing 3-dimensional colorized digital dental model assisted by digital photography].

PubMed

Ye, Hong-qiang; Liu, Yu-shu; Liu, Yun-song; Ning, Jing; Zhao, Yi-jiao; Zhou, Yong-sheng

2016-02-18

To explore a method of constructing universal 3-dimensional (3D) colorized digital dental model which can be displayed and edited in common 3D software (such as Geomagic series), in order to improve the visual effect of digital dental model in 3D software. The morphological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS), constructing 3D digital dental models. The 3D digital dental models were exported as STL files. Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD), five selected digital photographs of patients'teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views) to capture the color data. In Geomagic Studio 2013, after STL file of 3D digital dental model being imported, digital photographs were projected on 3D digital dental model with corresponding position and angle. The junctions of different photos were carefully trimmed to get continuous and natural color transitions. Then the 3D colorized digital dental model was constructed, which was exported as OBJ file or WRP file which was a special file for software of Geomagic series. For the purpose of evaluating the visual effect of the 3D colorized digital model, a rating scale on color simulation effect in views of patients'evaluation was used. Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded. The data were analyzed using McNemar-Bowker test in SPSS 20. Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application, the 3D colorized digital dental models, combined with 3D face images, were introduced into 3D smile design of aesthetic rehabilitation, which could improve the patients' cognition for the esthetic digital design and virtual prosthetic effect. Universal 3D colorized

Pedagogical Praxis Surrounding the Integration of Photography, Visual Literacy, Digital Literacy, and Educational Technology into Business Education Classrooms: A Focus Group Study

ERIC Educational Resources Information Center

Schlosser, Peter Allen

2010-01-01

This paper reports on an investigation into how Marketing and Business Education Teachers utilize and integrate educational technology into curriculum through the use of photography. The ontology of this visual, technological, and language interface is explored with an eye toward visual literacy, digital literacy, and pedagogical praxis, focusing…

Offline Signature Verification Using the Discrete Radon Transform and a Hidden Markov Model

NASA Astrophysics Data System (ADS)

Coetzer, J.; Herbst, B. M.; du Preez, J. A.

2004-12-01

We developed a system that automatically authenticates offline handwritten signatures using the discrete Radon transform (DRT) and a hidden Markov model (HMM). Given the robustness of our algorithm and the fact that only global features are considered, satisfactory results are obtained. Using a database of 924 signatures from 22 writers, our system achieves an equal error rate (EER) of 18% when only high-quality forgeries (skilled forgeries) are considered and an EER of 4.5% in the case of only casual forgeries. These signatures were originally captured offline. Using another database of 4800 signatures from 51 writers, our system achieves an EER of 12.2% when only skilled forgeries are considered. These signatures were originally captured online and then digitally converted into static signature images. These results compare well with the results of other algorithms that consider only global features.

Methyl-CpG island-associated genome signature tags

DOEpatents

Dunn, John J

2014-05-20

Disclosed is a method for analyzing the organismic complexity of a sample through analysis of the nucleic acid in the sample. In the disclosed method, through a series of steps, including digestion with a type II restriction enzyme, ligation of capture adapters and linkers and digestion with a type IIS restriction enzyme, genome signature tags are produced. The sequences of a statistically significant number of the signature tags are determined and the sequences are used to identify and quantify the organisms in the sample. Various embodiments of the invention described herein include methods for using single point genome signature tags to analyze the related families present in a sample, methods for analyzing sequences associated with hyper- and hypo-methylated CpG islands, methods for visualizing organismic complexity change in a sampling location over time and methods for generating the genome signature tag profile of a sample of fragmented DNA.

Polarimetric signature imaging of anisotropic bio-medical tissues

NASA Astrophysics Data System (ADS)

Wu, Stewart H.; Yang, De-Ming; Chiou, Arthur; Nee, Soe-Mie F.; Nee, Tsu-Wei

2010-02-01

Polarimetric imaging of Stokes vector (I, Q, U, V) can provide 4 independent signatures showing the linear and circular polarizations of biological tissues and cells. Using a recently developed Stokes digital imaging system, we measured the Stokes vector images of tissue samples from sections of rat livers containing normal portions and hematomas. The derived Mueller matrix elements can quantitatively provide multi-signature data of the bio-sample. This polarimetric optical technology is a new option of biosensing technology to inspect the structures of tissue samples, particularly for discriminating tumor and non-tumor biopsy. This technology is useful for critical disease discrimination and medical diagnostics applications.

Contextualising the topographic signature of historic mining, a scaling analysis

NASA Astrophysics Data System (ADS)

Reinhardt, Liam

2017-04-01

Mining is globally one of the most significant means by which humans alter landscapes; we do so through erosion (mining), transport, and deposition of extracted sediments (waste). The iconic Dartmoor mountain landscape of SW England ( 700km2) has experienced over 1000 years of shallow (Cu & Sn) mining that has left a pervasive imprint on the landscape. The availability of high resolution digital elevation models (<=1m) and aerial photographs @12.5 cm resolution) combined with historic records of mining activity and output make this an ideal location to investigate the topographic signature of mining. Conceptually I ask the question: how much (digital elevation model) smoothing is required to remove the human imprint from this landscape ? While we may have entered the Anthropocene other gravity driven process have imparted distinct scale-dependant signatures. How might the human signature differ from these processes and how pervasive is it at the landscape scale? Spatial scaling analysis (curvature & semi-variance) was used to quantify the topographic signature of historic mining and to determine how it differs to a) natural landforms such as bedrock tors; and b) the morphology of biological activity (e.g. peat formation). Other forms of historic activity such as peat cutting and quarrying were also investigated. The existence of 400 years of mine activity archives also makes it possible to distinguish between the imprint of differing forms of mine technology and their spatio-temporal signature. Interestingly the higher technology 19th C mines have left a much smaller topographic legacy than Medieval miners; though the former had a much greater impact in terms of heavy metal contamination.

The Integrity of Digital Information: Mechanics and Definitional Issues.

ERIC Educational Resources Information Center

Lynch, Clifford A.

1994-01-01

Considers issues regarding the migration of a system of literature into electronic formats. Highlights include integrity in an information distribution system; digest technology; tracings that permit detection of copied digital objects; verifying sources; digital signature technology and cryptography; electronic publishing; and intellectual…

Visual Literacy Skills of Students in College-Level Biology: Learning Outcomes Following Digital or Hand-Drawing Activities

ERIC Educational Resources Information Center

Bell, Justine C.

2014-01-01

To test the claim that digital learning tools enhance the acquisition of visual literacy in this generation of biology students, a learning intervention was carried out with 33 students enrolled in an introductory college biology course. This study compared learning outcomes following two types of learning tools: a traditional drawing activity, or…

A Prototype of Mathematical Treatment of Pen Pressure Data for Signature Verification.

PubMed

Li, Chi-Keung; Wong, Siu-Kay; Chim, Lai-Chu Joyce

2018-01-01

A prototype using simple mathematical treatment of the pen pressure data recorded by a digital pen movement recording device was derived. In this study, a total of 48 sets of signature and initial specimens were collected. Pearson's correlation coefficient was used to compare the data of the pen pressure patterns. From the 820 pair comparisons of the 48 sets of genuine signatures, a high degree of matching was found in which 95.4% (782 pairs) and 80% (656 pairs) had rPA > 0.7 and rPA > 0.8, respectively. In the comparison of the 23 forged signatures with their corresponding control signatures, 20 of them (89.2% of pairs) had rPA values < 0.6, showing a lower degree of matching when compared with the results of the genuine signatures. The prototype could be used as a complementary technique to improve the objectivity of signature examination and also has a good potential to be developed as a tool for automated signature identification. © 2017 American Academy of Forensic Sciences.

Extraction and analysis of signatures from the Gene Expression Omnibus by the crowd

PubMed Central

Wang, Zichen; Monteiro, Caroline D.; Jagodnik, Kathleen M.; Fernandez, Nicolas F.; Gundersen, Gregory W.; Rouillard, Andrew D.; Jenkins, Sherry L.; Feldmann, Axel S.; Hu, Kevin S.; McDermott, Michael G.; Duan, Qiaonan; Clark, Neil R.; Jones, Matthew R.; Kou, Yan; Goff, Troy; Woodland, Holly; Amaral, Fabio M R.; Szeto, Gregory L.; Fuchs, Oliver; Schüssler-Fiorenza Rose, Sophia M.; Sharma, Shvetank; Schwartz, Uwe; Bausela, Xabier Bengoetxea; Szymkiewicz, Maciej; Maroulis, Vasileios; Salykin, Anton; Barra, Carolina M.; Kruth, Candice D.; Bongio, Nicholas J.; Mathur, Vaibhav; Todoric, Radmila D; Rubin, Udi E.; Malatras, Apostolos; Fulp, Carl T.; Galindo, John A.; Motiejunaite, Ruta; Jüschke, Christoph; Dishuck, Philip C.; Lahl, Katharina; Jafari, Mohieddin; Aibar, Sara; Zaravinos, Apostolos; Steenhuizen, Linda H.; Allison, Lindsey R.; Gamallo, Pablo; de Andres Segura, Fernando; Dae Devlin, Tyler; Pérez-García, Vicente; Ma'ayan, Avi

2016-01-01

Gene expression data are accumulating exponentially in public repositories. Reanalysis and integration of themed collections from these studies may provide new insights, but requires further human curation. Here we report a crowdsourcing project to annotate and reanalyse a large number of gene expression profiles from Gene Expression Omnibus (GEO). Through a massive open online course on Coursera, over 70 participants from over 25 countries identify and annotate 2,460 single-gene perturbation signatures, 839 disease versus normal signatures, and 906 drug perturbation signatures. All these signatures are unique and are manually validated for quality. Global analysis of these signatures confirms known associations and identifies novel associations between genes, diseases and drugs. The manually curated signatures are used as a training set to develop classifiers for extracting similar signatures from the entire GEO repository. We develop a web portal to serve these signatures for query, download and visualization. PMID:27667448

Extraction and analysis of signatures from the Gene Expression Omnibus by the crowd.

PubMed

Wang, Zichen; Monteiro, Caroline D; Jagodnik, Kathleen M; Fernandez, Nicolas F; Gundersen, Gregory W; Rouillard, Andrew D; Jenkins, Sherry L; Feldmann, Axel S; Hu, Kevin S; McDermott, Michael G; Duan, Qiaonan; Clark, Neil R; Jones, Matthew R; Kou, Yan; Goff, Troy; Woodland, Holly; Amaral, Fabio M R; Szeto, Gregory L; Fuchs, Oliver; Schüssler-Fiorenza Rose, Sophia M; Sharma, Shvetank; Schwartz, Uwe; Bausela, Xabier Bengoetxea; Szymkiewicz, Maciej; Maroulis, Vasileios; Salykin, Anton; Barra, Carolina M; Kruth, Candice D; Bongio, Nicholas J; Mathur, Vaibhav; Todoric, Radmila D; Rubin, Udi E; Malatras, Apostolos; Fulp, Carl T; Galindo, John A; Motiejunaite, Ruta; Jüschke, Christoph; Dishuck, Philip C; Lahl, Katharina; Jafari, Mohieddin; Aibar, Sara; Zaravinos, Apostolos; Steenhuizen, Linda H; Allison, Lindsey R; Gamallo, Pablo; de Andres Segura, Fernando; Dae Devlin, Tyler; Pérez-García, Vicente; Ma'ayan, Avi

2016-09-26

Gene expression data are accumulating exponentially in public repositories. Reanalysis and integration of themed collections from these studies may provide new insights, but requires further human curation. Here we report a crowdsourcing project to annotate and reanalyse a large number of gene expression profiles from Gene Expression Omnibus (GEO). Through a massive open online course on Coursera, over 70 participants from over 25 countries identify and annotate 2,460 single-gene perturbation signatures, 839 disease versus normal signatures, and 906 drug perturbation signatures. All these signatures are unique and are manually validated for quality. Global analysis of these signatures confirms known associations and identifies novel associations between genes, diseases and drugs. The manually curated signatures are used as a training set to develop classifiers for extracting similar signatures from the entire GEO repository. We develop a web portal to serve these signatures for query, download and visualization.

Visualization of hyperspectral imagery

NASA Astrophysics Data System (ADS)

Hogervorst, Maarten A.; Bijl, Piet; Toet, Alexander

2007-04-01

We developed four new techniques to visualize hyper spectral image data for man-in-the-loop target detection. The methods respectively: (1) display the subsequent bands as a movie ("movie"), (2) map the data onto three channels and display these as a colour image ("colour"), (3) display the correlation between the pixel signatures and a known target signature ("match") and (4) display the output of a standard anomaly detector ("anomaly"). The movie technique requires no assumptions about the target signature and involves no information loss. The colour technique produces a single image that can be displayed in real-time. A disadvantage of this technique is loss of information. A display of the match between a target signature and pixels and can be interpreted easily and fast, but this technique relies on precise knowledge of the target signature. The anomaly detector signifies pixels with signatures that deviate from the (local) background. We performed a target detection experiment with human observers to determine their relative performance with the four techniques,. The results show that the "match" presentation yields the best performance, followed by "movie" and "anomaly", while performance with the "colour" presentation was the poorest. Each scheme has its advantages and disadvantages and is more or less suited for real-time and post-hoc processing. The rationale is that the final interpretation is best done by a human observer. In contrast to automatic target recognition systems, the interpretation of hyper spectral imagery by the human visual system is robust to noise and image transformations and requires a minimal number of assumptions (about signature of target and background, target shape etc.) When more knowledge about target and background is available this may be used to help the observer interpreting the data (aided target detection).

Authentication of digital video evidence

NASA Astrophysics Data System (ADS)

Beser, Nicholas D.; Duerr, Thomas E.; Staisiunas, Gregory P.

2003-11-01

In response to a requirement from the United States Postal Inspection Service, the Technical Support Working Group tasked The Johns Hopkins University Applied Physics Laboratory (JHU/APL) to develop a technique tha will ensure the authenticity, or integrity, of digital video (DV). Verifiable integrity is needed if DV evidence is to withstand a challenge to its admissibility in court on the grounds that it can be easily edited. Specifically, the verification technique must detect additions, deletions, or modifications to DV and satisfy the two-part criteria pertaining to scientific evidence as articulated in Daubert et al. v. Merrell Dow Pharmaceuticals Inc., 43 F3d (9th Circuit, 1995). JHU/APL has developed a prototype digital video authenticator (DVA) that generates digital signatures based on public key cryptography at the frame level of the DV. Signature generation and recording is accomplished at the same time as DV is recorded by the camcorder. Throughput supports the consumer-grade camcorder data rate of 25 Mbps. The DVA software is implemented on a commercial laptop computer, which is connected to a commercial digital camcorder via the IEEE-1394 serial interface. A security token provides agent identification and the interface to the public key infrastructure (PKI) that is needed for management of the public keys central to DV integrity verification.

Optical, analog and digital domain architectural considerations for visual communications

NASA Astrophysics Data System (ADS)

Metz, W. A.

2008-01-01

The end of the performance entitlement historically achieved by classic scaling of CMOS devices is within sight, driven ultimately by fundamental limits. Performance entitlements predicted by classic CMOS scaling have progressively failed to be realized in recent process generations due to excessive leakage, increasing interconnect delays and scaling of gate dielectrics. Prior to reaching fundamental limits, trends in technology, architecture and economics will pressure the industry to adopt new paradigms. A likely response is to repartition system functions away from digital implementations and into new architectures. Future architectures for visual communications will require extending the implementation into the optical and analog processing domains. The fundamental properties of these domains will in turn give rise to new architectural concepts. The limits of CMOS scaling and impact on architectures will be briefly reviewed. Alternative approaches in the optical, electronic and analog domains will then be examined for advantages, architectural impact and drawbacks.

Visual Memories Bypass Normalization.

PubMed

Bloem, Ilona M; Watanabe, Yurika L; Kibbe, Melissa M; Ling, Sam

2018-05-01

How distinct are visual memory representations from visual perception? Although evidence suggests that briefly remembered stimuli are represented within early visual cortices, the degree to which these memory traces resemble true visual representations remains something of a mystery. Here, we tested whether both visual memory and perception succumb to a seemingly ubiquitous neural computation: normalization. Observers were asked to remember the contrast of visual stimuli, which were pitted against each other to promote normalization either in perception or in visual memory. Our results revealed robust normalization between visual representations in perception, yet no signature of normalization occurring between working memory stores-neither between representations in memory nor between memory representations and visual inputs. These results provide unique insight into the nature of visual memory representations, illustrating that visual memory representations follow a different set of computational rules, bypassing normalization, a canonical visual computation.

Towards Trustable Digital Evidence with PKIDEV: PKI Based Digital Evidence Verification Model

NASA Astrophysics Data System (ADS)

Uzunay, Yusuf; Incebacak, Davut; Bicakci, Kemal

How to Capture and Preserve Digital Evidence Securely? For the investigation and prosecution of criminal activities that involve computers, digital evidence collected in the crime scene has a vital importance. On one side, it is a very challenging task for forensics professionals to collect them without any loss or damage. On the other, there is the second problem of providing the integrity and authenticity in order to achieve legal acceptance in a court of law. By conceiving digital evidence simply as one instance of digital data, it is evident that modern cryptography offers elegant solutions for this second problem. However, to our knowledge, there is not any previous work proposing a systematic model having a holistic view to address all the related security problems in this particular case of digital evidence verification. In this paper, we present PKIDEV (Public Key Infrastructure based Digital Evidence Verification model) as an integrated solution to provide security for the process of capturing and preserving digital evidence. PKIDEV employs, inter alia, cryptographic techniques like digital signatures and secure time-stamping as well as latest technologies such as GPS and EDGE. In our study, we also identify the problems public-key cryptography brings when it is applied to the verification of digital evidence.

21 CFR 1311.25 - Requirements for obtaining a CSOS digital certificate.

Code of Federal Regulations, 2013 CFR

2013-04-01

... public keys, the corresponding private key must be used to sign the certificate request. Verification of the signature using the public key in the request will serve as proof of possession of the private key. ... certification of the public digital signature key. After the request is approved, the Certification Authority...

21 CFR 1311.25 - Requirements for obtaining a CSOS digital certificate.

Code of Federal Regulations, 2012 CFR

2012-04-01

... public keys, the corresponding private key must be used to sign the certificate request. Verification of the signature using the public key in the request will serve as proof of possession of the private key. ... certification of the public digital signature key. After the request is approved, the Certification Authority...

21 CFR 1311.25 - Requirements for obtaining a CSOS digital certificate.

Code of Federal Regulations, 2014 CFR

2014-04-01

... public keys, the corresponding private key must be used to sign the certificate request. Verification of the signature using the public key in the request will serve as proof of possession of the private key. ... certification of the public digital signature key. After the request is approved, the Certification Authority...

The terrain signatures of administrative units: a tool for environmental assessment.

PubMed

Miliaresis, George Ch

2009-03-01

The quantification of knowledge related to the terrain and the landuse/landcover of administrative units in Southern Greece (Peloponnesus) is performed from the CGIAR-CSI SRTM digital elevation model and the CORINE landuse/landcover database. Each administrative unit is parametrically represented by a set of attributes related to its relief. Administrative units are classified on the basis of K-means cluster analysis in an attempt to see how they are organized into groups and cluster derived geometric signatures are defined. Finally each cluster is parametrically represented on the basis of the occurrence of the Corine landuse/landcover classes included and thus, landcover signatures are derived. The geometric and the landuse/landcover signatures revealed a terrain dependent landuse/landcover organization that was used in the assessment of the forest fires impact at moderate resolution scale.

Comparison of caries detection methods using varying numbers of intra-oral digital photographs with visual examination for epidemiology in children

PubMed Central

2013-01-01

Background This was a method comparison study. The aim of study was to compare caries information obtained from a full mouth visual examination using the method developed by the British Association for the Study of Community Dentistry (BASCD) for epidemiological surveys with caries data obtained from eight, six and four intra-oral digital photographs of index teeth in two groups of children aged 5 years and 10/11 years. Methods Five trained and calibrated examiners visually examined the whole mouth of 240 5-year-olds and 250 10-/11-year-olds using the BASCD method. The children also had intra-oral digital photographs taken of index teeth. The same 5 examiners assessed the intra-oral digital photographs (in groups of 8, 6 and 4 intra-oral photographs) for caries using the BASCD criteria; dmft/DMFT were used to compute Weighted Kappa Statistic as a measure of intra-examiner reliability and intra-class correlation coefficients as a measure of inter-examiner reliability for each method. A method comparison analysis was performed to determine the 95% limits of agreement for all five examiners, comparing the visual examination method with the photographic assessment method using 8, 6 and 4 intra-oral photographs. Results The intra-rater reliability for the visual examinations ranged from 0.81 to 0.94 in the 5-year-olds and 0.90 to 0.97 in the 10-/11-year-olds. Those for the photographic assessments in the 5-year-olds were for 8 intra-oral photographs, 0.86 to 0.94, for 6 intra-oral photographs, 0.85 to 0.98 and for 4 intra-oral photographs, 0.80 to 0.96; for the 10-/11-year-olds were for 8 intra-oral photographs 0.84 to 1.00, for 6 intra-oral photographs 0.82 to 1.00 and for 4 intra-oral photographs 0.72 to 0.98. The 95% limits of agreement were −1.997 to 1.967, -2.375 to 2.735 and −2.250 to 2.921 respectively for the 5-year-olds and −2.614 to 2.027, -2.179 to 3.887 and −2.594 to 2.163 respectively for the 10-/11-year-olds. Conclusions The photographic

Visual Memories Bypass Normalization

PubMed Central

Bloem, Ilona M.; Watanabe, Yurika L.; Kibbe, Melissa M.; Ling, Sam

2018-01-01

How distinct are visual memory representations from visual perception? Although evidence suggests that briefly remembered stimuli are represented within early visual cortices, the degree to which these memory traces resemble true visual representations remains something of a mystery. Here, we tested whether both visual memory and perception succumb to a seemingly ubiquitous neural computation: normalization. Observers were asked to remember the contrast of visual stimuli, which were pitted against each other to promote normalization either in perception or in visual memory. Our results revealed robust normalization between visual representations in perception, yet no signature of normalization occurring between working memory stores—neither between representations in memory nor between memory representations and visual inputs. These results provide unique insight into the nature of visual memory representations, illustrating that visual memory representations follow a different set of computational rules, bypassing normalization, a canonical visual computation. PMID:29596038

Mirage: a visible signature evaluation tool

NASA Astrophysics Data System (ADS)

Culpepper, Joanne B.; Meehan, Alaster J.; Shao, Q. T.; Richards, Noel

2017-10-01

This paper presents the Mirage visible signature evaluation tool, designed to provide a visible signature evaluation capability that will appropriately reflect the effect of scene content on the detectability of targets, providing a capability to assess visible signatures in the context of the environment. Mirage is based on a parametric evaluation of input images, assessing the value of a range of image metrics and combining them using the boosted decision tree machine learning method to produce target detectability estimates. It has been developed using experimental data from photosimulation experiments, where human observers search for vehicle targets in a variety of digital images. The images used for tool development are synthetic (computer generated) images, showing vehicles in many different scenes and exhibiting a wide variation in scene content. A preliminary validation has been performed using k-fold cross validation, where 90% of the image data set was used for training and 10% of the image data set was used for testing. The results of the k-fold validation from 200 independent tests show a prediction accuracy between Mirage predictions of detection probability and observed probability of detection of r(262) = 0:63, p < 0:0001 (Pearson correlation) and a MAE = 0:21 (mean absolute error).

Triage Visualization for Digital Media Exploitation

DTIC Science & Technology

2013-09-01

and responding to threats. Previous work includes NVisionIP [17], a network visualization 8 tool that processes Argus NetFlow [18] data. NVisionIP...2012.02.021 [17] K. Lakkaraju et al., “Nvisionip: netflow visualizations of system state for security situational awareness,” in Proceedings of the 2004 ACM

Digital Rocks Portal: Preservation, Sharing, Remote Visualization and Automated Analysis of Imaged Datasets

NASA Astrophysics Data System (ADS)

Prodanovic, M.; Esteva, M.; Ketcham, R. A.; Hanlon, M.; Pettengill, M.; Ranganath, A.; Venkatesh, A.

2016-12-01

Due to advances in imaging modalities such as X-ray microtomography and scattered electron microscopy, 2D and 3D imaged datasets of rock microstructure on nanometer to centimeter length scale allow investigation of nonlinear flow and mechanical phenomena using numerical approaches. This in turn produces various upscaled parameters required by subsurface flow and deformation simulators. However, a single research group typically specializes in an imaging modality and/or related modeling on a single length scale, and lack of data-sharing infrastructure makes it difficult to integrate different length scales. We developed a sustainable, open and easy-to-use repository called the Digital Rocks Portal (http://www.digitalrocksportal.org), that (1) organizes images and related experimental measurements of different porous materials, (2) improves access to them for a wider community of geosciences or engineering researchers not necessarily trained in computer science or data analysis. Our objective is to enable scientific inquiry and engineering decisions founded on a data-driven basis. We show how the data loaded in the portal can be documented, referenced in publications via digital object identifiers, visualize and linked to other repositories. We then show preliminary results on integrating remote parallel visualization and flow simulation workflow with the pore structures currently stored in the repository. We finally discuss the issues of collecting correct metadata, data discoverability and repository sustainability. This is the first repository for this particular data, but is part of the wider ecosystem of geoscience data and model cyber-infrastructure called "Earthcube" (http://earthcube.org/) sponsored by National Science Foundation. For data sustainability and continuous access, the portal is implemented within the reliable, 24/7 maintained High Performance Computing Infrastructure supported by the Texas Advanced Computing Center (TACC) at the University of

Authentication, Time-Stamping and Digital Signatures

NASA Technical Reports Server (NTRS)

Levine, Judah

1996-01-01

Time and frequency data are often transmitted over public packet-switched networks, and the use of this mode of distribution is likely to increase in the near future as high-speed logical circuits transmitted via networks replace point-to-point physical circuits. ALthough these networks have many technical advantages, they are susceptible to evesdropping, spoofing, and the alteration of messages enroute using techniques that are relatively simple to implement and quite difficult to detect. I will discuss a number of solutions to these problems, including the authentication mechanism used in the Network Time Protocol (NTP) and the more general technique of signing time-stamps using public key cryptography. This public key method can also be used to implement the digital analog of a Notary Public, and I will discuss how such a system could be realized on a public network such as the Internet.

eCTG: an automatic procedure to extract digital cardiotocographic signals from digital images.

PubMed

Sbrollini, Agnese; Agostinelli, Angela; Marcantoni, Ilaria; Morettini, Micaela; Burattini, Luca; Di Nardo, Francesco; Fioretti, Sandro; Burattini, Laura

2018-03-01

Cardiotocography (CTG), consisting in the simultaneous recording of fetal heart rate (FHR) and maternal uterine contractions (UC), is a popular clinical test to assess fetal health status. Typically, CTG machines provide paper reports that are visually interpreted by clinicians. Consequently, visual CTG interpretation depends on clinician's experience and has a poor reproducibility. The lack of databases containing digital CTG signals has limited number and importance of retrospective studies finalized to set up procedures for automatic CTG analysis that could contrast visual CTG interpretation subjectivity. In order to help overcoming this problem, this study proposes an electronic procedure, termed eCTG, to extract digital CTG signals from digital CTG images, possibly obtainable by scanning paper CTG reports. eCTG was specifically designed to extract digital CTG signals from digital CTG images. It includes four main steps: pre-processing, Otsu's global thresholding, signal extraction and signal calibration. Its validation was performed by means of the "CTU-UHB Intrapartum Cardiotocography Database" by Physionet, that contains digital signals of 552 CTG recordings. Using MATLAB, each signal was plotted and saved as a digital image that was then submitted to eCTG. Digital CTG signals extracted by eCTG were eventually compared to corresponding signals directly available in the database. Comparison occurred in terms of signal similarity (evaluated by the correlation coefficient ρ, and the mean signal error MSE) and clinical features (including FHR baseline and variability; number, amplitude and duration of tachycardia, bradycardia, acceleration and deceleration episodes; number of early, variable, late and prolonged decelerations; and UC number, amplitude, duration and period). The value of ρ between eCTG and reference signals was 0.85 (P < 10 -560 ) for FHR and 0.97 (P < 10 -560 ) for UC. On average, MSE value was 0.00 for both FHR and UC. No CTG feature

Visually testing the dynamic character of a blazed-angle adjustable grating by digital holographic microscopy.

PubMed

Qin, Chuan; Zhao, Jianlin; Di, Jianglei; Wang, Le; Yu, Yiting; Yuan, Weizheng

2009-02-10

We employed digital holographic microscopy to visually test microoptoelectromechanical systems (MOEMS). The sample is a blazed-angle adjustable grating. Considering the periodic structure of the sample, a local area unwrapping method based on a binary template was adopted to demodulate the fringes obtained by referring to a reference hologram. A series of holograms at different deformation states due to different drive voltages were captured to analyze the dynamic character of the MOEMS, and the uniformity of different microcantilever beams was also inspected. The results show this testing method is effective for a periodic structure.

Radiological assessment of breast density by visual classification (BI-RADS) compared to automated volumetric digital software (Quantra): implications for clinical practice.

PubMed

Regini, Elisa; Mariscotti, Giovanna; Durando, Manuela; Ghione, Gianluca; Luparia, Andrea; Campanino, Pier Paolo; Bianchi, Caterina Chiara; Bergamasco, Laura; Fonio, Paolo; Gandini, Giovanni

2014-10-01

This study was done to assess breast density on digital mammography and digital breast tomosynthesis according to the visual Breast Imaging Reporting and Data System (BI-RADS) classification, to compare visual assessment with Quantra software for automated density measurement, and to establish the role of the software in clinical practice. We analysed 200 digital mammograms performed in 2D and 3D modality, 100 of which positive for breast cancer and 100 negative. Radiological density was assessed with the BI-RADS classification; a Quantra density cut-off value was sought on the 2D images only to discriminate between BI-RADS categories 1-2 and BI-RADS 3-4. Breast density was correlated with age, use of hormone therapy, and increased risk of disease. The agreement between the 2D and 3D assessments of BI-RADS density was high (K 0.96). A cut-off value of 21% is that which allows us to best discriminate between BI-RADS categories 1-2 and 3-4. Breast density was negatively correlated to age (r = -0.44) and positively to use of hormone therapy (p = 0.0004). Quantra density was higher in breasts with cancer than in healthy breasts. There is no clear difference between the visual assessments of density on 2D and 3D images. Use of the automated system requires the adoption of a cut-off value (set at 21%) to effectively discriminate BI-RADS 1-2 and 3-4, and could be useful in clinical practice.

Symbol processing in the left angular gyrus: evidence from passive perception of digits.

PubMed

Price, Gavin R; Ansari, Daniel

2011-08-01

Arabic digits are one of the most ubiquitous symbol sets in the world. While there have been many investigations into the neural processing of the semantic information digits represent (e.g. through numerical comparison tasks), little is known about the neural mechanisms which support the processing of digits as visual symbols. To characterise the component neurocognitive mechanisms which underlie numerical cognition, it is essential to understand the processing of digits as a visual category, independent of numerical magnitude processing. The 'Triple Code Model' (Dehaene, 1992; Dehaene and Cohen, 1995) posits an asemantic visual code for processing Arabic digits in the ventral visual stream, yet there is currently little empirical evidence in support of this code. This outstanding question was addressed in the current functional Magnetic Resonance (fMRI) study by contrasting brain responses during the passive viewing of digits versus letters and novel symbols at short (50 ms) and long (500 ms) presentation times. The results of this study reveal increased activation for familiar symbols (digits and letters) relative to unfamiliar symbols (scrambled digits and letters) at long presentation durations in the left dorsal Angular gyrus (dAG). Furthermore, increased activation for Arabic digits was observed in the left ventral Angular gyrus (vAG) in comparison to letters, scrambled digits and scrambled letters at long presentation durations, but no digit specific activation in any region at short presentation durations. These results suggest an absence of a digit specific 'Visual Number Form Area' (VNFA) in the ventral visual cortex, and provide evidence for the role of the left ventral AG during the processing of digits in the absence of any explicit processing demands. We conclude that Arabic digit processing depends specifically on the left AG rather than a ventral visual stream VNFA. Copyright © 2011 Elsevier Inc. All rights reserved.

Dichotic and dichoptic digit perception in normal adults.

PubMed

Lawfield, Angela; McFarland, Dennis J; Cacace, Anthony T

2011-06-01

Verbally based dichotic-listening experiments and reproduction-mediated response-selection strategies have been used for over four decades to study perceptual/cognitive aspects of auditory information processing and make inferences about hemispheric asymmetries and language lateralization in the brain. Test procedures using dichotic digits have also been used to assess for disorders of auditory processing. However, with this application, limitations exist and paradigms need to be developed to improve specificity of the diagnosis. Use of matched tasks in multiple sensory modalities is a logical approach to address this issue. Herein, we use dichotic listening and dichoptic viewing of visually presented digits for making this comparison. To evaluate methodological issues involved in using matched tasks of dichotic listening and dichoptic viewing in normal adults. A multivariate assessment of the effects of modality (auditory vs. visual), digit-span length (1-3 pairs), response selection (recognition vs. reproduction), and ear/visual hemifield of presentation (left vs. right) on dichotic and dichoptic digit perception. Thirty adults (12 males, 18 females) ranging in age from 18 to 30 yr with normal hearing sensitivity and normal or corrected-to-normal visual acuity. A computerized, custom-designed program was used for all data collection and analysis. A four-way repeated measures analysis of variance (ANOVA) evaluated the effects of modality, digit-span length, response selection, and ear/visual field of presentation. The ANOVA revealed that performances on dichotic listening and dichoptic viewing tasks were dependent on complex interactions between modality, digit-span length, response selection, and ear/visual hemifield of presentation. Correlation analysis suggested a common effect on overall accuracy of performance but isolated only an auditory factor for a laterality index. The variables used in this experiment affected performances in the auditory modality to a

10 CFR 2.304 - Formal requirements for documents; signatures; acceptance for filing.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Management for NRC Adjudicatory Hearings § 2.304 Formal requirements for documents; signatures; acceptance... section, it may be struck. (1) An electronic document must be signed using a participant's or a... paragraph (d) of this section. (i) When signing an electronic document using a digital ID certificate, the...

10 CFR 2.304 - Formal requirements for documents; signatures; acceptance for filing.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Management for NRC Adjudicatory Hearings § 2.304 Formal requirements for documents; signatures; acceptance... section, it may be struck. (1) An electronic document must be signed using a participant's or a... paragraph (d) of this section. (i) When signing an electronic document using a digital ID certificate, the...

Investigating Mathematics through Digital Media: Cognitive Visual Perturbations

ERIC Educational Resources Information Center

Calder, Nigel

2011-01-01

How might investigating mathematical tasks through digital media influence students' learning trajectories, and hence their mathematical thinking? This article reports on elements of an ongoing study that examines how engaging mathematical phenomena through digital pedagogical media might influence understanding. As the students sought…

The spectrum of genomic signatures: from dinucleotides to chaos game representation.

PubMed

Wang, Yingwei; Hill, Kathleen; Singh, Shiva; Kari, Lila

2005-02-14

In the post genomic era, access to complete genome sequence data for numerous diverse species has opened multiple avenues for examining and comparing primary DNA sequence organization of entire genomes. Previously, the concept of a genomic signature was introduced with the observation of species-type specific Dinucleotide Relative Abundance Profiles (DRAPs); dinucleotides were identified as the subsequences with the greatest bias in representation in a majority of genomes. Herein, we demonstrate that DRAP is one particular genomic signature contained within a broader spectrum of signatures. Within this spectrum, an alternative genomic signature, Chaos Game Representation (CGR), provides a unique visualization of patterns in sequence organization. A genomic signature is associated with a particular integer order or subsequence length that represents a measure of the resolution or granularity in the analysis of primary DNA sequence organization. We quantitatively explore the organizational information provided by genomic signatures of different orders through different distance measures, including a novel Image Distance. The Image Distance and other existing distance measures are evaluated by comparing the phylogenetic trees they generate for 26 complete mitochondrial genomes from a diversity of species. The phylogenetic tree generated by the Image Distance is compatible with the known relatedness of species. Quantitative evaluation of the spectrum of genomic signatures may be used to ultimately gain insight into the determinants and biological relevance of the genome signatures.

Experimental Measurements of Sonic Boom Signatures Using a Continuous Data Acquisition Technique

NASA Technical Reports Server (NTRS)

Wilcox, Floyd J.; Elmiligui, Alaa A.

2013-01-01

A wind tunnel investigation was conducted in the Langley Unitary Plan Wind Tunnel to determine the effectiveness of a technique to measure aircraft sonic boom signatures using a single conical survey probe while continuously moving the model past the probe. Sonic boom signatures were obtained using both move-pause and continuous data acquisition methods for comparison. The test was conducted using a generic business jet model at a constant angle of attack and a single model-to-survey-probe separation distance. The sonic boom signatures were obtained at a Mach number of 2.0 and a unit Reynolds number of 2 million per foot. The test results showed that it is possible to obtain sonic boom signatures while continuously moving the model and that the time required to acquire the signature is at least 10 times faster than the move-pause method. Data plots are presented with a discussion of the results. No tabulated data or flow visualization photographs are included.

E-learning platform for automated testing of electronic circuits using signature analysis method

NASA Astrophysics Data System (ADS)

Gherghina, Cǎtǎlina; Bacivarov, Angelica; Bacivarov, Ioan C.; Petricǎ, Gabriel

2016-12-01

Dependability of electronic circuits can be ensured only through testing of circuit modules. This is done by generating test vectors and their application to the circuit. Testability should be viewed as a concerted effort to ensure maximum efficiency throughout the product life cycle, from conception and design stage, through production to repairs during products operating. In this paper, is presented the platform developed by authors for training for testability in electronics, in general and in using signature analysis method, in particular. The platform allows highlighting the two approaches in the field namely analog and digital signature of circuits. As a part of this e-learning platform, it has been developed a database for signatures of different electronic components meant to put into the spotlight different techniques implying fault detection, and from this there were also self-repairing techniques of the systems with this kind of components. An approach for realizing self-testing circuits based on MATLAB environment and using signature analysis method is proposed. This paper analyses the benefits of signature analysis method and simulates signature analyzer performance based on the use of pseudo-random sequences, too.

Educational Impact of Digital Visualization Tools on Digital Character Production Computer Science Courses

ERIC Educational Resources Information Center

van Langeveld, Mark Christensen

2009-01-01

Digital character production courses have traditionally been taught in art departments. The digital character production course at the University of Utah is centered, drawing uniformly from art and engineering disciplines. Its design has evolved to include a synergy of computer science, functional art and human anatomy. It gives students an…

Digital holography of intracellular dynamics to probe tissue physiology.

PubMed

Merrill, Daniel; An, Ran; Turek, John; Nolte, David D

2015-01-01

Digital holography provides improved capabilities for imaging through dense tissue. Using a short-coherence source, the digital hologram recorded from backscattered light performs laser ranging that maintains fidelity of information acquired from depths much greater than possible by traditional imaging techniques. Biodynamic imaging (BDI) is a developing technology for live-tissue imaging of up to a millimeter in depth that uses the hologram intensity fluctuations as label-free image contrast and can study tissue behavior in native microenvironments. In this paper BDI is used to investigate the change in adhesion-dependent tissue response in 3D cultures. The results show that increasing density of cellular adhesions slows motion inside tissue and alters the response to cytoskeletal drugs. A clear signature of membrane fluctuations was observed in mid-frequencies (0.1-1 Hz) and was enhanced by the application of cytochalasin-D that degrades the actin cortex inside the cell membrane. This enhancement feature is only observed in tissues that have formed adhesions, because cell pellets initially do not show this signature, but develop this signature only after incubation enables adhesions to form.

Interacting with Visual Poems through AR-Based Digital Artwork

ERIC Educational Resources Information Center

Lin, Hao-Chiang Koong; Hsieh, Min-Chai; Liu, Eric Zhi-Feng; Chuang, Tsung-Yen

2012-01-01

In this study, an AR-based digital artwork called "Mind Log" was designed and evaluated. The augmented reality technique was employed to create digital artwork that would present interactive poems. A digital poem was generated via the interplay between a video film and a text-based poem. This artwork was created following a rigorous design flow,…

Integrative Analysis of Disease Signatures Shows Inflammation Disrupts Juvenile Experience-Dependent Cortical Plasticity

PubMed Central

Smith, Milo R.; Burman, Poromendro

2016-01-01

Throughout childhood and adolescence, periods of heightened neuroplasticity are critical for the development of healthy brain function and behavior. Given the high prevalence of neurodevelopmental disorders, such as autism, identifying disruptors of developmental plasticity represents an essential step for developing strategies for prevention and intervention. Applying a novel computational approach that systematically assessed connections between 436 transcriptional signatures of disease and multiple signatures of neuroplasticity, we identified inflammation as a common pathological process central to a diverse set of diseases predicted to dysregulate plasticity signatures. We tested the hypothesis that inflammation disrupts developmental cortical plasticity in vivo using the mouse ocular dominance model of experience-dependent plasticity in primary visual cortex. We found that the administration of systemic lipopolysaccharide suppressed plasticity during juvenile critical period with accompanying transcriptional changes in a particular set of molecular regulators within primary visual cortex. These findings suggest that inflammation may have unrecognized adverse consequences on the postnatal developmental trajectory and indicate that treating inflammation may reduce the burden of neurodevelopmental disorders. PMID:28101530

Three-Year-Old Photographers: Educational and Parental Mediation as a Basis for Visual Literacy via Digital Photography in Early Childhood

ERIC Educational Resources Information Center

Friedman, Arielle

2016-01-01

The study examines two years of an educational program for children aged three to four, based on the use of digital cameras. It assesses the program's effects on the children and adults involved in the project, and explores how they help the youngsters acquire visual literacy. Operating under the assumption that formal curricula usually…

Spatiotemporal Visualization of Time-Series Satellite-Derived CO2 Flux Data Using Volume Rendering and Gpu-Based Interpolation on a Cloud-Driven Digital Earth

NASA Astrophysics Data System (ADS)

Wu, S.; Yan, Y.; Du, Z.; Zhang, F.; Liu, R.

2017-10-01

The ocean carbon cycle has a significant influence on global climate, and is commonly evaluated using time-series satellite-derived CO2 flux data. Location-aware and globe-based visualization is an important technique for analyzing and presenting the evolution of climate change. To achieve realistic simulation of the spatiotemporal dynamics of ocean carbon, a cloud-driven digital earth platform is developed to support the interactive analysis and display of multi-geospatial data, and an original visualization method based on our digital earth is proposed to demonstrate the spatiotemporal variations of carbon sinks and sources using time-series satellite data. Specifically, a volume rendering technique using half-angle slicing and particle system is implemented to dynamically display the released or absorbed CO2 gas. To enable location-aware visualization within the virtual globe, we present a 3D particlemapping algorithm to render particle-slicing textures onto geospace. In addition, a GPU-based interpolation framework using CUDA during real-time rendering is designed to obtain smooth effects in both spatial and temporal dimensions. To demonstrate the capabilities of the proposed method, a series of satellite data is applied to simulate the air-sea carbon cycle in the China Sea. The results show that the suggested strategies provide realistic simulation effects and acceptable interactive performance on the digital earth.

Eating with our eyes: From visual hunger to digital satiation.

PubMed

Spence, Charles; Okajima, Katsunori; Cheok, Adrian David; Petit, Olivia; Michel, Charles

2016-12-01

One of the brain's key roles is to facilitate foraging and feeding. It is presumably no coincidence, then, that the mouth is situated close to the brain in most animal species. However, the environments in which our brains evolved were far less plentiful in terms of the availability of food resources (i.e., nutriments) than is the case for those of us living in the Western world today. The growing obesity crisis is but one of the signs that humankind is not doing such a great job in terms of optimizing the contemporary food landscape. While the blame here is often put at the doors of the global food companies - offering addictive foods, designed to hit 'the bliss point' in terms of the pleasurable ingredients (sugar, salt, fat, etc.), and the ease of access to calorie-rich foods - we wonder whether there aren't other implicit cues in our environments that might be triggering hunger more often than is perhaps good for us. Here, we take a closer look at the potential role of vision; Specifically, we question the impact that our increasing exposure to images of desirable foods (what is often labelled 'food porn', or 'gastroporn') via digital interfaces might be having, and ask whether it might not inadvertently be exacerbating our desire for food (what we call 'visual hunger'). We review the growing body of cognitive neuroscience research demonstrating the profound effect that viewing such images can have on neural activity, physiological and psychological responses, and visual attention, especially in the 'hungry' brain. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Management of digital eye strain.

PubMed

Coles-Brennan, Chantal; Sulley, Anna; Young, Graeme

2018-05-23

Digital eye strain, an emerging public health issue, is a condition characterised by visual disturbance and/or ocular discomfort related to the use of digital devices and resulting from a range of stresses on the ocular environment. This review aims to provide an overview of the extensive literature on digital eye strain research with particular reference to the clinical management of symptoms. As many as 90 per cent of digital device users experience symptoms of digital eye strain. Many studies suggest that the following factors are associated with digital eye strain: uncorrected refractive error (including presbyopia), accommodative and vergence anomalies, altered blinking pattern (reduced rate and incomplete blinking), excessive exposure to intense light, closer working distance, and smaller font size. Since a symptom may be caused by one or more factors, a holistic approach should be adopted. The following management strategies have been suggested: (i) appropriate correction of refractive error, including astigmatism and presbyopia; (ii) management of vergence anomalies, with the aim of inducing or leaving a small amount of heterophoria (~1.5 Δ Exo); (iii) blinking exercise/training to maintain normal blinking pattern; (iv) use of lubricating eye drops (artificial tears) to help alleviate dry eye-related symptoms; (v) contact lenses with enhanced comfort, particularly at end-of-day and in challenging environments; (vi) prescription of colour filters in all vision correction options, especially blue light-absorbing filters; and (vii) management of accommodative anomalies. Prevention is the main strategy for management of digital eye strain, which involves: (i) ensuring an ergonomic work environment and practice (through patient education and the implementation of ergonomic workplace policies); and (ii) visual examination and eye care to treat visual disorders. Special consideration is needed for people at a high risk of digital eye strain, such as computer

Visual attention: Linking prefrontal sources to neuronal and behavioral correlates.

PubMed

Clark, Kelsey; Squire, Ryan Fox; Merrikhi, Yaser; Noudoost, Behrad

2015-09-01

Attention is a means of flexibly selecting and enhancing a subset of sensory input based on the current behavioral goals. Numerous signatures of attention have been identified throughout the brain, and now experimenters are seeking to determine which of these signatures are causally related to the behavioral benefits of attention, and the source of these modulations within the brain. Here, we review the neural signatures of attention throughout the brain, their theoretical benefits for visual processing, and their experimental correlations with behavioral performance. We discuss the importance of measuring cue benefits as a way to distinguish between impairments on an attention task, which may instead be visual or motor impairments, and true attentional deficits. We examine evidence for various areas proposed as sources of attentional modulation within the brain, with a focus on the prefrontal cortex. Lastly, we look at studies that aim to link sources of attention to its neuronal signatures elsewhere in the brain. Copyright © 2015. Published by Elsevier Ltd.

(abstract) Topographic Signatures in Geology

NASA Technical Reports Server (NTRS)

Farr, Tom G.; Evans, Diane L.

1996-01-01

Topographic information is required for many Earth Science investigations. For example, topography is an important element in regional and global geomorphic studies because it reflects the interplay between the climate-driven processes of erosion and the tectonic processes of uplift. A number of techniques have been developed to analyze digital topographic data, including Fourier texture analysis. A Fourier transform of the topography of an area allows the spatial frequency content of the topography to be analyzed. Band-pass filtering of the transform produces images representing the amplitude of different spatial wavelengths. These are then used in a multi-band classification to map units based on their spatial frequency content. The results using a radar image instead of digital topography showed good correspondence to a geologic map, however brightness variations in the image unrelated to topography caused errors. An additional benefit to the use of Fourier band-pass images for the classification is that the textural signatures of the units are quantative measures of the spatial characteristics of the units that may be used to map similar units in similar environments.

Testing the accuracy of timing reports in visual timing tasks with a consumer-grade digital camera.

PubMed

Smyth, Rachael E; Oram Cardy, Janis; Purcell, David

2017-06-01

This study tested the accuracy of a visual timing task using a readily available and relatively inexpensive consumer grade digital camera. A visual inspection time task was recorded using short high-speed video clips and the timing as reported by the task's program was compared to the timing as recorded in the video clips. Discrepancies in these two timing reports were investigated further and based on display refresh rate, a decision was made whether the discrepancy was large enough to affect the results as reported by the task. In this particular study, the errors in timing were not large enough to impact the results of the study. The procedure presented in this article offers an alternative method for performing a timing test, which uses readily available hardware and can be used to test the timing in any software program on any operating system and display.

Lung cancer signature biomarkers: tissue specific semantic similarity based clustering of digital differential display (DDD) data.

PubMed

Srivastava, Mousami; Khurana, Pankaj; Sugadev, Ragumani

2012-11-02

The tissue-specific Unigene Sets derived from more than one million expressed sequence tags (ESTs) in the NCBI, GenBank database offers a platform for identifying significantly and differentially expressed tissue-specific genes by in-silico methods. Digital differential display (DDD) rapidly creates transcription profiles based on EST comparisons and numerically calculates, as a fraction of the pool of ESTs, the relative sequence abundance of known and novel genes. However, the process of identifying the most likely tissue for a specific disease in which to search for candidate genes from the pool of differentially expressed genes remains difficult. Therefore, we have used 'Gene Ontology semantic similarity score' to measure the GO similarity between gene products of lung tissue-specific candidate genes from control (normal) and disease (cancer) sets. This semantic similarity score matrix based on hierarchical clustering represents in the form of a dendrogram. The dendrogram cluster stability was assessed by multiple bootstrapping. Multiple bootstrapping also computes a p-value for each cluster and corrects the bias of the bootstrap probability. Subsequent hierarchical clustering by the multiple bootstrapping method (α = 0.95) identified seven clusters. The comparative, as well as subtractive, approach revealed a set of 38 biomarkers comprising four distinct lung cancer signature biomarker clusters (panel 1-4). Further gene enrichment analysis of the four panels revealed that each panel represents a set of lung cancer linked metastasis diagnostic biomarkers (panel 1), chemotherapy/drug resistance biomarkers (panel 2), hypoxia regulated biomarkers (panel 3) and lung extra cellular matrix biomarkers (panel 4). Expression analysis reveals that hypoxia induced lung cancer related biomarkers (panel 3), HIF and its modulating proteins (TGM2, CSNK1A1, CTNNA1, NAMPT/Visfatin, TNFRSF1A, ETS1, SRC-1, FN1, APLP2, DMBT1/SAG, AIB1 and AZIN1) are significantly down regulated

Frequency-band signatures of visual responses to naturalistic input in ferret primary visual cortex during free viewing.

PubMed

Sellers, Kristin K; Bennett, Davis V; Fröhlich, Flavio

2015-02-19

Neuronal firing responses in visual cortex reflect the statistics of visual input and emerge from the interaction with endogenous network dynamics. Artificial visual stimuli presented to animals in which the network dynamics were constrained by anesthetic agents or trained behavioral tasks have provided fundamental understanding of how individual neurons in primary visual cortex respond to input. In contrast, very little is known about the mesoscale network dynamics and their relationship to microscopic spiking activity in the awake animal during free viewing of naturalistic visual input. To address this gap in knowledge, we recorded local field potential (LFP) and multiunit activity (MUA) simultaneously in all layers of primary visual cortex (V1) of awake, freely viewing ferrets presented with naturalistic visual input (nature movie clips). We found that naturalistic visual stimuli modulated the entire oscillation spectrum; low frequency oscillations were mostly suppressed whereas higher frequency oscillations were enhanced. In average across all cortical layers, stimulus-induced change in delta and alpha power negatively correlated with the MUA responses, whereas sensory-evoked increases in gamma power positively correlated with MUA responses. The time-course of the band-limited power in these frequency bands provided evidence for a model in which naturalistic visual input switched V1 between two distinct, endogenously present activity states defined by the power of low (delta, alpha) and high (gamma) frequency oscillatory activity. Therefore, the two mesoscale activity states delineated in this study may define the degree of engagement of the circuit with the processing of sensory input. Copyright © 2014 Elsevier B.V. All rights reserved.

Digital Images and Human Vision

NASA Technical Reports Server (NTRS)

Watson, Andrew B.; Null, Cynthia H. (Technical Monitor)

1997-01-01

Processing of digital images destined for visual consumption raises many interesting questions regarding human visual sensitivity. This talk will survey some of these questions, including some that have been answered and some that have not. There will be an emphasis upon visual masking, and a distinction will be drawn between masking due to contrast gain control processes, and due to processes such as hypothesis testing, pattern recognition, and visual search.

PathEdEx - Uncovering High-explanatory Visual Diagnostics Heuristics Using Digital Pathology and Multiscale Gaze Data.

PubMed

Shin, Dmitriy; Kovalenko, Mikhail; Ersoy, Ilker; Li, Yu; Doll, Donald; Shyu, Chi-Ren; Hammer, Richard

2017-01-01

Visual heuristics of pathology diagnosis is a largely unexplored area where reported studies only provided a qualitative insight into the subject. Uncovering and quantifying pathology visual and nonvisual diagnostic patterns have great potential to improve clinical outcomes and avoid diagnostic pitfalls. Here, we present PathEdEx, an informatics computational framework that incorporates whole-slide digital pathology imaging with multiscale gaze-tracking technology to create web-based interactive pathology educational atlases and to datamine visual and nonvisual diagnostic heuristics. We demonstrate the capabilities of PathEdEx for mining visual and nonvisual diagnostic heuristics using the first PathEdEx volume of a hematopathology atlas. We conducted a quantitative study on the time dynamics of zooming and panning operations utilized by experts and novices to come to the correct diagnosis. We then performed association rule mining to determine sets of diagnostic factors that consistently result in a correct diagnosis, and studied differences in diagnostic strategies across different levels of pathology expertise using Markov chain (MC) modeling and MC Monte Carlo simulations. To perform these studies, we translated raw gaze points to high-explanatory semantic labels that represent pathology diagnostic clues. Therefore, the outcome of these studies is readily transformed into narrative descriptors for direct use in pathology education and practice. PathEdEx framework can be used to capture best practices of pathology visual and nonvisual diagnostic heuristics that can be passed over to the next generation of pathologists and have potential to streamline implementation of precision diagnostics in precision medicine settings.

Critique and Process: Signature Pedagogies in the Graphic Design Classroom

ERIC Educational Resources Information Center

Motley, Phillip

2017-01-01

Like many disciplines in design and the visual fine arts, critique is a signature pedagogy in the graphic design classroom. It serves as both a formative and summative assessment while also giving students the opportunity to practice the habits of graphic design. Critiques help students become keen observers of relevant disciplinary criteria;…

Visualization-by-Sketching: An Artist's Interface for Creating Multivariate Time-Varying Data Visualizations.

PubMed

Schroeder, David; Keefe, Daniel F

2016-01-01

We present Visualization-by-Sketching, a direct-manipulation user interface for designing new data visualizations. The goals are twofold: First, make the process of creating real, animated, data-driven visualizations of complex information more accessible to artists, graphic designers, and other visual experts with traditional, non-technical training. Second, support and enhance the role of human creativity in visualization design, enabling visual experimentation and workflows similar to what is possible with traditional artistic media. The approach is to conceive of visualization design as a combination of processes that are already closely linked with visual creativity: sketching, digital painting, image editing, and reacting to exemplars. Rather than studying and tweaking low-level algorithms and their parameters, designers create new visualizations by painting directly on top of a digital data canvas, sketching data glyphs, and arranging and blending together multiple layers of animated 2D graphics. This requires new algorithms and techniques to interpret painterly user input relative to data "under" the canvas, balance artistic freedom with the need to produce accurate data visualizations, and interactively explore large (e.g., terabyte-sized) multivariate datasets. Results demonstrate a variety of multivariate data visualization techniques can be rapidly recreated using the interface. More importantly, results and feedback from artists support the potential for interfaces in this style to attract new, creative users to the challenging task of designing more effective data visualizations and to help these users stay "in the creative zone" as they work.

Effect of temperature on the visualization by digital color mapping of latent fingerprint deposits on metal.

PubMed

Peel, Alicia; Bond, John W

2014-03-01

Visualization of fingerprint deposits by digital color mapping of light reflected from the surface of heated brass, copper, aluminum, and tin has been investigated using Adobe® Photoshop®. Metals were heated to a range of temperatures (T) between 50°C and 500°C in 50°C intervals with enhancement being optimal when the metals are heated to 250°C, 350°C, 50°C, and 300°C, respectively, and the hue values adjusted to 247°, 245°, 5°, and 34°, respectively. Fingerprint visualization after color mapping was not degraded by subsequent washing of the metals and color mapping did not compromise the visibility of the fingerprint for all values of T. The optimum value of T for fingerprint visibility is significantly dependent of the standard reduction potential of the metal with Kendall’s Tau (τ) = 0.953 (p < 0.001). For brass, this correlation is obtained when considering the standard reduction potential of zinc rather than copper.

A digital future for the history of psychology?

PubMed

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).

Infrared Signature Modeling and Analysis of Aircraft Plume

NASA Astrophysics Data System (ADS)

Rao, Arvind G.

2011-09-01

In recent years, the survivability of an aircraft has been put to task more than ever before. One of the main reasons is the increase in the usage of Infrared (IR) guided Anti-Aircraft Missiles, especially due to the availability of Man Portable Air Defence System (MANPADS) with some terrorist groups. Thus, aircraft IR signatures are gaining more importance as compared to their radar, visual, acoustic, or any other signatures. The exhaust plume ejected from the aircraft is one of the important sources of IR signature in military aircraft that use low bypass turbofan engines for propulsion. The focus of the present work is modelling of spectral IR radiation emission from the exhaust jet of a typical military aircraft and to evaluate the aircraft susceptibility in terms of the aircraft lock-on range due to its plume emission, for a simple case against a typical Surface to Air Missile (SAM). The IR signature due to the aircraft plume is examined in a holistic manner. A comprehensive methodology of computing IR signatures and its affect on aircraft lock-on range is elaborated. Commercial CFD software has been used to predict the plume thermo-physical properties and subsequently an in-house developed code was used for evaluating the IR radiation emitted by the plume. The LOWTRAN code has been used for modeling the atmospheric IR characteristics. The results obtained from these models are in reasonable agreement with some available experimental data. The analysis carried out in this paper succinctly brings out the intricacy of the radiation emitted by various gaseous species in the plume and the role of atmospheric IR transmissivity in dictating the plume IR signature as perceived by an IR guided SAM.

High brightness, low coherence, digital holographic microscopy for 3D visualization of an in-vitro sandwiched biological sample.

PubMed

Abdelsalam, D G; Yasui, Takeshi

2017-05-01

We achieve practically a bright-field digital holographic microscopy (DHM) configuration free from coherent noise for three-dimensional (3D) visualization of an in-vitro sandwiched sarcomere sample. Visualization of such sandwiched samples by conventional atomic force microscope (AFM) is impossible, while visualization using DHM with long coherent lengths is challenging. The proposed configuration is comprised of an ultrashort pulse laser source and a Mach-Zehnder interferometer in transmission. Periodically poled lithium niobate (PPLN) crystal was used to convert the fundamental beam by second harmonic generation (SHG) to the generated beam fit to the CCD camera used. The experimental results show that the contrast of the reconstructed phase image is improved to a higher degree compared to a He-Ne laser based result. We attribute this improvement to two things: the feature of the femtosecond pulse light, which acts as a chopper for coherent noise suppression, and the fact that the variance of a coherent mode can be reduced by a factor of 9 due to low loss through a nonlinear medium.

Visualization of genome signatures of eukaryote genomes by batch-learning self-organizing map with a special emphasis on Drosophila genomes.

PubMed

Abe, Takashi; Hamano, Yuta; Ikemura, Toshimichi

2014-01-01

A strategy of evolutionary studies that can compare vast numbers of genome sequences is becoming increasingly important with the remarkable progress of high-throughput DNA sequencing methods. We previously established a sequence alignment-free clustering method "BLSOM" for di-, tri-, and tetranucleotide compositions in genome sequences, which can characterize sequence characteristics (genome signatures) of a wide range of species. In the present study, we generated BLSOMs for tetra- and pentanucleotide compositions in approximately one million sequence fragments derived from 101 eukaryotes, for which almost complete genome sequences were available. BLSOM recognized phylotype-specific characteristics (e.g., key combinations of oligonucleotide frequencies) in the genome sequences, permitting phylotype-specific clustering of the sequences without any information regarding the species. In our detailed examination of 12 Drosophila species, the correlation between their phylogenetic classification and the classification on the BLSOMs was observed to visualize oligonucleotides diagnostic for species-specific clustering.

Signatures support program

NASA Astrophysics Data System (ADS)

Hawley, Chadwick T.

2009-05-01

The Signatures Support Program (SSP) leverages the full spectrum of signature-related activities (collections, processing, development, storage, maintenance, and dissemination) within the Department of Defense (DOD), the intelligence community (IC), other Federal agencies, and civil institutions. The Enterprise encompasses acoustic, seismic, radio frequency, infrared, radar, nuclear radiation, and electro-optical signatures. The SSP serves the war fighter, the IC, and civil institutions by supporting military operations, intelligence operations, homeland defense, disaster relief, acquisitions, and research and development. Data centers host and maintain signature holdings, collectively forming the national signatures pool. The geographically distributed organizations are the authoritative sources and repositories for signature data; the centers are responsible for data content and quality. The SSP proactively engages DOD, IC, other Federal entities, academia, and industry to locate signatures for inclusion in the distributed national signatures pool and provides world-wide 24/7 access via the SSP application.

Real Traceable Signatures

NASA Astrophysics Data System (ADS)

Chow, Sherman S. M.

Traceable signature scheme extends a group signature scheme with an enhanced anonymity management mechanism. The group manager can compute a tracing trapdoor which enables anyone to test if a signature is signed by a given misbehaving user, while the only way to do so for group signatures requires revealing the signer of all signatures. Nevertheless, it is not tracing in a strict sense. For all existing schemes, T tracing agents need to recollect all N' signatures ever produced and perform RN' “checks” for R revoked users. This involves a high volume of transfer and computations. Increasing T increases the degree of parallelism for tracing but also the probability of “missing” some signatures in case some of the agents are dishonest.

Perceptibility curve test for digital radiographs before and after correction for attenuation and correction for attenuation and visual response.

PubMed

Li, G; Welander, U; Yoshiura, K; Shi, X-Q; McDavid, W D

2003-11-01

Two digital image processing methods, correction for X-ray attenuation and correction for attenuation and visual response, have been developed. The aim of the present study was to compare digital radiographs before and after correction for attenuation and correction for attenuation and visual response by means of a perceptibility curve test. Radiographs were exposed of an aluminium test object containing holes ranging from 0.03 mm to 0.30 mm with increments of 0.03 mm. Fourteen radiographs were exposed with the Dixi system (Planmeca Oy, Helsinki, Finland) and twelve radiographs were exposed with the F1 iOX system (Fimet Oy, Monninkylä, Finland) from low to high exposures covering the full exposure ranges of the systems. Radiographs obtained from the Dixi and F1 iOX systems were 12 bit and 8 bit images, respectively. Original radiographs were then processed for correction for attenuation and correction for attenuation and visual response. Thus, two series of radiographs were created. Ten viewers evaluated all the radiographs in the same random order under the same viewing conditions. The object detail having the lowest perceptible contrast was recorded for each observer. Perceptibility curves were plotted according to the mean of observer data. The perceptibility curves for processed radiographs obtained with the F1 iOX system are higher than those for originals in the exposure range up to the peak, where the curves are basically the same. For radiographs exposed with the Dixi system, perceptibility curves for processed radiographs are higher than those for originals for all exposures. Perceptibility curves show that for 8 bit radiographs obtained from the F1 iOX system, the contrast threshold was increased in processed radiographs up to the peak, while for 12 bit radiographs obtained with the Dixi system, the contrast threshold was increased in processed radiographs for all exposures. When comparisons were made between radiographs corrected for attenuation and

Digital Quantification of Goldmann Visual Fields (GVF) as a Means for Genotype-Phenotype Comparisons and Detection of Progression in Retinal Degenerations

PubMed Central

Zahid, Sarwar; Peeler, Crandall; Khan, Naheed; Davis, Joy; Mahmood, Mahdi; Heckenlively, John; Jayasundera, Thiran

2015-01-01

Purpose To develop a reliable and efficient digital method to quantify planimetric Goldmann visual field (GVF) data to monitor disease course and treatment responses in retinal degenerative diseases. Methods A novel method to digitally quantify GVF using Adobe Photoshop CS3 was developed for comparison to traditional digital planimetry (Placom 45C digital planimeter; EngineerSupply, Lynchburg, Virginia, USA). GVFs from 20 eyes from 10 patients with Stargardt disease were quantified to assess the difference between the two methods (a total of 230 measurements per method). This quantification approach was also applied to 13 patients with X-linked retinitis pigmentosa (XLRP) with mutations in RPGR. Results Overall, measurements using Adobe Photoshop were more rapidly performed than those using conventional planimetry. Photoshop measurements also exhibited less inter- and intra-observer variability. GVF areas for the I4e isopter in patients with the same mutation in RPGR who were nearby in age had similar qualitative and quantitative areas. Conclusions Quantification of GVF using Adobe Photoshop is quicker, more reliable, and less-user dependent than conventional digital planimetry. It will be a useful tool for both retrospective and prospective studies of disease course as well as for monitoring treatment response in clinical trials for retinal degenerative diseases. PMID:24664690

Digital quantification of Goldmann visual fields (GVFs) as a means for genotype-phenotype comparisons and detection of progression in retinal degenerations.

PubMed

Zahid, Sarwar; Peeler, Crandall; Khan, Naheed; Davis, Joy; Mahmood, Mahdi; Heckenlively, John R; Jayasundera, Thiran

2014-01-01

To develop a reliable and efficient digital method to quantify planimetric Goldmann visual field (GVF) data to monitor disease course and treatment responses in retinal degenerative diseases. A novel method to digitally quantify GVFs using Adobe Photoshop CS3 was developed for comparison to traditional digital planimetry (Placom 45C digital planimeter; Engineer Supply, Lynchburg, Virginia, USA). GVFs from 20 eyes from 10 patients with Stargardt disease were quantified to assess the difference between the two methods (a total of 230 measurements per method). This quantification approach was also applied to 13 patients with X-linked retinitis pigmentosa (XLRP) with mutations in RPGR. Overall, measurements using Adobe Photoshop were more rapidly performed than those using conventional planimetry. Photoshop measurements also exhibited less inter- and intraobserver variability. GVF areas for the I4e isopter in patients with the same mutation in RPGR who were nearby in age had similar qualitative and quantitative areas. Quantification of GVFs using Adobe Photoshop is quicker, more reliable, and less user dependent than conventional digital planimetry. It will be a useful tool for both retrospective and prospective studies of disease course as well as for monitoring treatment response in clinical trials for retinal degenerative diseases.

PathEdEx – Uncovering High-explanatory Visual Diagnostics Heuristics Using Digital Pathology and Multiscale Gaze Data

PubMed Central

Shin, Dmitriy; Kovalenko, Mikhail; Ersoy, Ilker; Li, Yu; Doll, Donald; Shyu, Chi-Ren; Hammer, Richard

2017-01-01

Background: Visual heuristics of pathology diagnosis is a largely unexplored area where reported studies only provided a qualitative insight into the subject. Uncovering and quantifying pathology visual and nonvisual diagnostic patterns have great potential to improve clinical outcomes and avoid diagnostic pitfalls. Methods: Here, we present PathEdEx, an informatics computational framework that incorporates whole-slide digital pathology imaging with multiscale gaze-tracking technology to create web-based interactive pathology educational atlases and to datamine visual and nonvisual diagnostic heuristics. Results: We demonstrate the capabilities of PathEdEx for mining visual and nonvisual diagnostic heuristics using the first PathEdEx volume of a hematopathology atlas. We conducted a quantitative study on the time dynamics of zooming and panning operations utilized by experts and novices to come to the correct diagnosis. We then performed association rule mining to determine sets of diagnostic factors that consistently result in a correct diagnosis, and studied differences in diagnostic strategies across different levels of pathology expertise using Markov chain (MC) modeling and MC Monte Carlo simulations. To perform these studies, we translated raw gaze points to high-explanatory semantic labels that represent pathology diagnostic clues. Therefore, the outcome of these studies is readily transformed into narrative descriptors for direct use in pathology education and practice. Conclusion: PathEdEx framework can be used to capture best practices of pathology visual and nonvisual diagnostic heuristics that can be passed over to the next generation of pathologists and have potential to streamline implementation of precision diagnostics in precision medicine settings. PMID:28828200

Shade matching assisted by digital photography and computer software.

PubMed

Schropp, Lars

2009-04-01

To evaluate the efficacy of digital photographs and graphic computer software for color matching compared to conventional visual matching. The shade of a tab from a shade guide (Vita 3D-Master Guide) placed in a phantom head was matched to a second guide of the same type by nine observers. This was done for twelve selected shade tabs (tests). The shade-matching procedure was performed visually in a simulated clinic environment and with digital photographs, and the time spent for both procedures was recorded. An alternative arrangement of the shade tabs was used in the digital photographs. In addition, a graphic software program was used for color analysis. Hue, chroma, and lightness values of the test tab and all tabs of the second guide were derived from the digital photographs. According to the CIE L*C*h* color system, the color differences between the test tab and tabs of the second guide were calculated. The shade guide tab that deviated least from the test tab was determined to be the match. Shade matching performance by means of graphic software was compared with the two visual methods and tested by Chi-square tests (alpha= 0.05). Eight of twelve test tabs (67%) were matched correctly by the computer software method. This was significantly better (p < 0.02) than the performance of the visual shade matching methods conducted in the simulated clinic (32% correct match) and with photographs (28% correct match). No correlation between time consumption for the visual shade matching methods and frequency of correct match was observed. Shade matching assisted by digital photographs and computer software was significantly more reliable than by conventional visual methods.

Supervised Multi-Authority Scheme with Blind Signature for IoT with Attribute Based Encryption

NASA Astrophysics Data System (ADS)

Nissenbaum, O. V.; Ponomarov, K. Y.; Zaharov, A. A.

2018-04-01

This article proposes a three-side cryptographic scheme for verifying device attributes with a Supervisor and a Certification Authority (CA) for attribute-based encryption. Two options are suggested: using a message authentication code and using a digital signature. The first version is suitable for networks with one CA, and the second one for networks with several CAs, including dynamic systems. Also, the addition of this scheme with a blind signature is proposed to preserve the confidentiality of the device attributes from the CA. The introduction gives a definition and a brief historical overview of attribute-based encryption (ABE), addresses the use of ABE in the Internet of Things.

Digital Rocks Portal: a Sustainable Platform for Data Management, Analysis and Remote Visualization of Volumetric Images of Porous Media

NASA Astrophysics Data System (ADS)

Prodanovic, M.; Esteva, M.; Ketcham, R. A.

2017-12-01

Nanometer to centimeter-scale imaging such as (focused ion beam) scattered electron microscopy, magnetic resonance imaging and X-ray (micro)tomography has since 1990s introduced 2D and 3D datasets of rock microstructure that allow investigation of nonlinear flow and mechanical phenomena on the length scales that are otherwise impervious to laboratory measurements. The numerical approaches that use such images produce various upscaled parameters required by subsurface flow and deformation simulators. All of this has revolutionized our knowledge about grain scale phenomena. However, a lack of data-sharing infrastructure among research groups makes it difficult to integrate different length scales. We have developed a sustainable, open and easy-to-use repository called the Digital Rocks Portal (https://www.digitalrocksportal.org), that (1) organizes images and related experimental measurements of different porous materials, (2) improves access to them for a wider community of engineering or geosciences researchers not necessarily trained in computer science or data analysis. Digital Rocks Portal (NSF EarthCube Grant 1541008) is the first repository for imaged porous microstructure data. It is implemented within the reliable, 24/7 maintained High Performance Computing Infrastructure supported by the Texas Advanced Computing Center (University of Texas at Austin). Long-term storage is provided through the University of Texas System Research Cyber-infrastructure initiative. We show how the data can be documented, referenced in publications via digital object identifiers (see Figure below for examples), visualized, searched for and linked to other repositories. We show recently implemented integration of the remote parallel visualization, bulk upload for large datasets as well as preliminary flow simulation workflow with the pore structures currently stored in the repository. We discuss the issues of collecting correct metadata, data discoverability and repository

Soil Science in the Digital Age

ERIC Educational Resources Information Center

High, Vance; VanHorn, Laura

2012-01-01

With the pervasiveness of digital technology, elementary students almost instinctively begin inquiry-based instruction with a bias. Visual information from digital devices competes with elementary science inquiry. To counteract this effect, teachers can use advance organizers. The advance organizer is a tool or a mental learning aid to help…

Quantifying radionuclide signatures from a γ-γ coincidence system.

PubMed

Britton, Richard; Jackson, Mark J; Davies, Ashley V

2015-11-01

A method for quantifying gamma coincidence signatures has been developed, and tested in conjunction with a high-efficiency multi-detector system to quickly identify trace amounts of radioactive material. The γ-γ system utilises fully digital electronics and list-mode acquisition to time-stamp each event, allowing coincidence matrices to be easily produced alongside typical 'singles' spectra. To quantify the coincidence signatures a software package has been developed to calculate efficiency and cascade summing corrected branching ratios. This utilises ENSDF records as an input, and can be fully automated, allowing the user to quickly and easily create/update a coincidence library that contains all possible γ and conversion electron cascades, associated cascade emission probabilities, and true-coincidence summing corrected γ cascade detection probabilities. It is also fully searchable by energy, nuclide, coincidence pair, γ multiplicity, cascade probability and half-life of the cascade. The probabilities calculated were tested using measurements performed on the γ-γ system, and found to provide accurate results for the nuclides investigated. Given the flexibility of the method, (it only relies on evaluated nuclear data, and accurate efficiency characterisations), the software can now be utilised for a variety of systems, quickly and easily calculating coincidence signature probabilities. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

The Visual Geophysical Exploration Environment: A Multi-dimensional Scientific Visualization

NASA Astrophysics Data System (ADS)

Pandya, R. E.; Domenico, B.; Murray, D.; Marlino, M. R.

2003-12-01

The Visual Geophysical Exploration Environment (VGEE) is an online learning environment designed to help undergraduate students understand fundamental Earth system science concepts. The guiding principle of the VGEE is the importance of hands-on interaction with scientific visualization and data. The VGEE consists of four elements: 1) an online, inquiry-based curriculum for guiding student exploration; 2) a suite of El Nino-related data sets adapted for student use; 3) a learner-centered interface to a scientific visualization tool; and 4) a set of concept models (interactive tools that help students understand fundamental scientific concepts). There are two key innovations featured in this interactive poster session. One is the integration of concept models and the visualization tool. Concept models are simple, interactive, Java-based illustrations of fundamental physical principles. We developed eight concept models and integrated them into the visualization tool to enable students to probe data. The ability to probe data using a concept model addresses the common problem of transfer: the difficulty students have in applying theoretical knowledge to everyday phenomenon. The other innovation is a visualization environment and data that are discoverable in digital libraries, and installed, configured, and used for investigations over the web. By collaborating with the Integrated Data Viewer developers, we were able to embed a web-launchable visualization tool and access to distributed data sets into the online curricula. The Thematic Real-time Environmental Data Distributed Services (THREDDS) project is working to provide catalogs of datasets that can be used in new VGEE curricula under development. By cataloging this curricula in the Digital Library for Earth System Education (DLESE), learners and educators can discover the data and visualization tool within a framework that guides their use.

Experiment research on infrared targets signature in mid and long IR spectral bands

NASA Astrophysics Data System (ADS)

Wang, Chensheng; Hong, Pu; Lei, Bo; Yue, Song; Zhang, Zhijie; Ren, Tingting

2013-09-01

Since the infrared imaging system has played a significant role in the military self-defense system and fire control system, the radiation signature of IR target becomes an important topic in IR imaging application technology. IR target signature can be applied in target identification, especially for small and dim targets, as well as the target IR thermal design. To research and analyze the targets IR signature systematically, a practical and experimental project is processed under different backgrounds and conditions. An infrared radiation acquisition system based on a MWIR cooled thermal imager and a LWIR cooled thermal imager is developed to capture the digital infrared images. Furthermore, some instruments are introduced to provide other parameters. According to the original image data and the related parameters in a certain scene, the IR signature of interested target scene can be calculated. Different background and targets are measured with this approach, and a comparison experiment analysis shall be presented in this paper as an example. This practical experiment has proved the validation of this research work, and it is useful in detection performance evaluation and further target identification research.

Digital Badges

ERIC Educational Resources Information Center

Frederiksen, Linda

2013-01-01

Unlike so much of the current vocabulary in education and technology that seems to stir more confusion than clarity, most public service librarians may already have a general idea about digital badges. As visual representations of individual accomplishments, competencies or skills that are awarded by groups, institutions, or organizations, they…

Deciphering protein signatures using color, morphological, and topological analysis of immunohistochemically stained human tissues

NASA Astrophysics Data System (ADS)

Zerhouni, Erwan; Prisacari, Bogdan; Zhong, Qing; Wild, Peter; Gabrani, Maria

2016-03-01

Images of tissue specimens enable evidence-based study of disease susceptibility and stratification. Moreover, staining technologies empower the evidencing of molecular expression patterns by multicolor visualization, thus enabling personalized disease treatment and prevention. However, translating molecular expression imaging into direct health benefits has been slow. Two major factors contribute to that. On the one hand, disease susceptibility and progression is a complex, multifactorial molecular process. Diseases, such as cancer, exhibit cellular heterogeneity, impeding the differentiation between diverse grades or types of cell formations. On the other hand, the relative quantification of the stained tissue selected features is ambiguous, tedious and time consuming, prone to clerical error, leading to intra- and inter-observer variability and low throughput. Image analysis of digital histopathology images is a fast-developing and exciting area of disease research that aims to address the above limitations. We have developed a computational framework that extracts unique signatures using color, morphological and topological information and allows the combination thereof. The integration of the above information enables diagnosis of disease with AUC as high as 0.97. Multiple staining show significant improvement with respect to most proteins, and an AUC as high as 0.99.

Digital Earth system based river basin data integration

NASA Astrophysics Data System (ADS)

Zhang, Xin; Li, Wanqing; Lin, Chao

2014-12-01

Digital Earth is an integrated approach to build scientific infrastructure. The Digital Earth systems provide a three-dimensional visualization and integration platform for river basin data which include the management data, in situ observation data, remote sensing observation data and model output data. This paper studies the Digital Earth system based river basin data integration technology. Firstly, the construction of the Digital Earth based three-dimensional river basin data integration environment is discussed. Then the river basin management data integration technology is presented which is realized by general database access interface, web service and ActiveX control. Thirdly, the in situ data stored in database tables as records integration is realized with three-dimensional model of the corresponding observation apparatus display in the Digital Earth system by a same ID code. In the next two parts, the remote sensing data and the model output data integration technologies are discussed in detail. The application in the Digital Zhang River basin System of China shows that the method can effectively improve the using efficiency and visualization effect of the data.

Panning artifacts in digital pathology images

NASA Astrophysics Data System (ADS)

Avanaki, Ali R. N.; Lanciault, Christian; Espig, Kathryn S.; Xthona, Albert; Kimpe, Tom R. L.

2017-03-01

In making a pathologic diagnosis, a pathologist uses cognitive processes: perception, attention, memory, and search (Pena and Andrade-Filho, 2009). Typically, this involves focus while panning from one region of a slide to another, using either a microscope in a traditional workflow or software program and display in a digital pathology workflow (DICOM Standard Committee, 2010). We theorize that during panning operation, the pathologist receives information important to diagnosis efficiency and/or correctness. As compared to an optical microscope, panning in a digital pathology image involves some visual artifacts due to the following: (i) the frame rate is finite; (ii) time varying visual signals are reconstructed using imperfect zero-order hold. Specifically, after pixel's digital drive is changed, it takes time for a pixel to emit the expected amount of light. Previous work suggests that 49% of navigation is conducted in low-power/overview with digital pathology (Molin et al., 2015), but the influence of display factors has not been measured. We conducted a reader study to establish a relationship between display frame rate, panel response time, and threshold panning speed (above which the artifacts become noticeable). Our results suggest visual tasks that involve tissue structure are more impacted by the simulated panning artifacts than those that only involve color (e.g., staining intensity estimation), and that the panning artifacts versus normalized panning speed has a peak behavior which is surprising and may change for a diagnostic task. This is work in progress and our final findings should be considered in designing future digital pathology systems.

Security analysis of boolean algebra based on Zhang-Wang digital signature scheme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Jinbin, E-mail: jbzheng518@163.com

2014-10-06

In 2005, Zhang and Wang proposed an improvement signature scheme without using one-way hash function and message redundancy. In this paper, we show that this scheme exits potential safety concerns through the analysis of boolean algebra, such as bitwise exclusive-or, and point out that mapping is not one to one between assembly instructions and machine code actually by means of the analysis of the result of the assembly program segment, and which possibly causes safety problems unknown to the software.

Information measures for terrain visualization

NASA Astrophysics Data System (ADS)

Bonaventura, Xavier; Sima, Aleksandra A.; Feixas, Miquel; Buckley, Simon J.; Sbert, Mateu; Howell, John A.

2017-02-01

Many quantitative and qualitative studies in geoscience research are based on digital elevation models (DEMs) and 3D surfaces to aid understanding of natural and anthropogenically-influenced topography. As well as their quantitative uses, the visual representation of DEMs can add valuable information for identifying and interpreting topographic features. However, choice of viewpoints and rendering styles may not always be intuitive, especially when terrain data are augmented with digital image texture. In this paper, an information-theoretic framework for object understanding is applied to terrain visualization and terrain view selection. From a visibility channel between a set of viewpoints and the component polygons of a 3D terrain model, we obtain three polygonal information measures. These measures are used to visualize the information associated with each polygon of the terrain model. In order to enhance the perception of the terrain's shape, we explore the effect of combining the calculated information measures with the supplementary digital image texture. From polygonal information, we also introduce a method to select a set of representative views of the terrain model. Finally, we evaluate the behaviour of the proposed techniques using example datasets. A publicly available framework for both the visualization and the view selection of a terrain has been created in order to provide the possibility to analyse any terrain model.

Designing a visualization system for hydrological data

NASA Astrophysics Data System (ADS)

Fuhrmann, Sven

2000-02-01

The field of hydrology is, as any other scientific field, strongly affected by a massive technological evolution. The spread of modern information and communication technology within the last three decades has led to an increased collection, availability and use of spatial and temporal digital hydrological data. In a two-year research period a working group in Muenster applied and developed methods for the visualization of digital hydrological data and the documentation of hydrological models. A low-cost multimedial, hydrological visualization system (HydroVIS) for the Weser river catchment was developed. The research group designed HydroVIS under freeware constraints and tried to show what kind of multimedia visualization techniques can be effectively used with a nonprofit hydrological visualization system. The system's visual components include features such as electronic maps, temporal and nontemporal cartographic animations, the display of geologic profiles, interactive diagrams and hypertext, including photographs and tables.

Color visual simulation applications at the Defense Mapping Agency

NASA Astrophysics Data System (ADS)

Simley, J. D.

1984-09-01

The Defense Mapping Agency (DMA) produces the Digital Landmass System data base to provide culture and terrain data in support of numerous aircraft simulators. In order to conduct data base and simulation quality control and requirements analysis, DMA has developed the Sensor Image Simulator which can rapidly generate visual and radar static scene digital simulations. The use of color in visual simulation allows the clear portrayal of both landcover and terrain data, whereas the initial black and white capabilities were restricted in this role and thus found limited use. Color visual simulation has many uses in analysis to help determine the applicability of current and prototype data structures to better meet user requirements. Color visual simulation is also significant in quality control since anomalies can be more easily detected in natural appearing forms of the data. The realism and efficiency possible with advanced processing and display technology, along with accurate data, make color visual simulation a highly effective medium in the presentation of geographic information. As a result, digital visual simulation is finding increased potential as a special purpose cartographic product. These applications are discussed and related simulation examples are presented.

Effectiveness of a Wedge Probe to Measure Sonic Boom Signatures in a Supersonic Wind Tunnel

NASA Technical Reports Server (NTRS)

Wilcox, Floyd J., Jr.; Elmiligui, Alaa A.

2013-01-01

A wind tunnel investigation was conducted in the Langley Unitary Plan Wind Tunnel (UPWT) to determine the effectiveness of a wedge probe to measure sonic boom pressure signatures compared to a slender conical probe. A generic business jet model at a constant angle of attack and at a single model to probe separation distance was used to generate a sonic boom signature. Pressure signature data were acquired with both the wedge probe and a slender conical probe for comparison. The test was conducted at a Mach number of 2.0 and a free-stream unit Reynolds number of 2 million per foot. The results showed that the wedge probe was not effective in measuring the sonic boom pressure signature of the aircraft model in the supersonic wind tunnel. Data plots and a discussion of the results are presented. No tabulated data or flow visualization photographs are included.

Evidence for signature whistles in Guiana dolphins (Sotalia guianensis) in Ilhéus, northeastern Brazil.

PubMed

Lima, Alice; Le Pendu, Yvonnick

2014-12-01

Signature whistles have been widely studied in bottlenose dolphins (Tursiops truncatus). A recent study suggested the occurrence of signature whistles in Guiana dolphins (Sotalia guianensis) but could not identify the whistlers. The objective of this study is to describe the whistle characteristics in the population of S. guianensis from Ilhéus and investigate the occurrence of signature whistles. Dolphins from 55 groups were photographed and sound emissions from 21 groups were recorded. The frequency parameters and duration of the 847 recorded whistles were similar to those recorded in 12 other populations, on an intermediate position of a latitudinal gradient. The visual classification method was applied to the spectrograms of 68 stereotyped potential signature whistles. Five out of 6 human judges agreed on the formation of 13 groups. The presence of the same individuals in different recording occasions of stereotyped whistles suggests that some whistle types are produced by specific individuals. The study is the first to use the photo-identification technique to identify Guiana dolphins emitting whistles and the results reinforce the hypothesis of signature whistles in this species.

Digital fabrication of multi-material biomedical objects.

PubMed

Cheung, H H; Choi, S H

2009-12-01

This paper describes a multi-material virtual prototyping (MMVP) system for modelling and digital fabrication of discrete and functionally graded multi-material objects for biomedical applications. The MMVP system consists of a DMMVP module, an FGMVP module and a virtual reality (VR) simulation module. The DMMVP module is used to model discrete multi-material (DMM) objects, while the FGMVP module is for functionally graded multi-material (FGM) objects. The VR simulation module integrates these two modules to perform digital fabrication of multi-material objects, which can be subsequently visualized and analysed in a virtual environment to optimize MMLM processes for fabrication of product prototypes. Using the MMVP system, two biomedical objects, including a DMM human spine and an FGM intervertebral disc spacer are modelled and digitally fabricated for visualization and analysis in a VR environment. These studies show that the MMVP system is a practical tool for modelling, visualization, and subsequent fabrication of biomedical objects of discrete and functionally graded multi-materials for biomedical applications. The system may be adapted to control MMLM machines with appropriate hardware for physical fabrication of biomedical objects.

Identification and Characteristics of Signature Whistles in Wild Bottlenose Dolphins (Tursiops truncatus) from Namibia

PubMed Central

Elwen, Simon Harvey; Nastasi, Aurora

2014-01-01

A signature whistle type is a learned, individually distinctive whistle type in a dolphin's acoustic repertoire that broadcasts the identity of the whistle owner. The acquisition and use of signature whistles indicates complex cognitive functioning that requires wider investigation in wild dolphin populations. Here we identify signature whistle types from a population of approximately 100 wild common bottlenose dolphins (Tursiops truncatus) inhabiting Walvis Bay, and describe signature whistle occurrence, acoustic parameters and temporal production. A catalogue of 43 repeatedly emitted whistle types (REWTs) was generated by analysing 79 hrs of acoustic recordings. From this, 28 signature whistle types were identified using a method based on the temporal patterns in whistle sequences. A visual classification task conducted by 5 naïve judges showed high levels of agreement in classification of whistles (Fleiss-Kappa statistic, κ = 0.848, Z = 55.3, P<0.001) and supported our categorisation. Signature whistle structure remained stable over time and location, with most types (82%) recorded in 2 or more years, and 4 identified at Walvis Bay and a second field site approximately 450 km away. Whistle acoustic parameters were consistent with those of signature whistles documented in Sarasota Bay (Florida, USA). We provide evidence of possible two-voice signature whistle production by a common bottlenose dolphin. Although signature whistle types have potential use as a marker for studying individual habitat use, we only identified approximately 28% of those from the Walvis Bay population, despite considerable recording effort. We found that signature whistle type diversity was higher in larger dolphin groups and groups with calves present. This is the first study describing signature whistles in a wild free-ranging T. truncatus population inhabiting African waters and it provides a baseline on which more in depth behavioural studies can be based. PMID:25203814

EO/IR scene generation open source initiative for real-time hardware-in-the-loop and all-digital simulation

NASA Astrophysics Data System (ADS)

Morris, Joseph W.; Lowry, Mac; Boren, Brett; Towers, James B.; Trimble, Darian E.; Bunfield, Dennis H.

2011-06-01

The US Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) and the Redstone Test Center (RTC) has formed the Scene Generation Development Center (SGDC) to support the Department of Defense (DoD) open source EO/IR Scene Generation initiative for real-time hardware-in-the-loop and all-digital simulation. Various branches of the DoD have invested significant resources in the development of advanced scene and target signature generation codes. The SGDC goal is to maintain unlimited government rights and controlled access to government open source scene generation and signature codes. In addition, the SGDC provides development support to a multi-service community of test and evaluation (T&E) users, developers, and integrators in a collaborative environment. The SGDC has leveraged the DoD Defense Information Systems Agency (DISA) ProjectForge (https://Project.Forge.mil) which provides a collaborative development and distribution environment for the DoD community. The SGDC will develop and maintain several codes for tactical and strategic simulation, such as the Joint Signature Image Generator (JSIG), the Multi-spectral Advanced Volumetric Real-time Imaging Compositor (MAVRIC), and Office of the Secretary of Defense (OSD) Test and Evaluation Science and Technology (T&E/S&T) thermal modeling and atmospherics packages, such as EOView, CHARM, and STAR. Other utility packages included are the ContinuumCore for real-time messaging and data management and IGStudio for run-time visualization and scenario generation.

Opportunities and challenges for digital morphology

PubMed Central

2010-01-01

Advances in digital data acquisition, analysis, and storage have revolutionized the work in many biological disciplines such as genomics, molecular phylogenetics, and structural biology, but have not yet found satisfactory acceptance in morphology. Improvements in non-invasive imaging and three-dimensional visualization techniques, however, permit high-throughput analyses also of whole biological specimens, including museum material. These developments pave the way towards a digital era in morphology. Using sea urchins (Echinodermata: Echinoidea), we provide examples illustrating the power of these techniques. However, remote visualization, the creation of a specialized database, and the implementation of standardized, world-wide accepted data deposition practices prior to publication are essential to cope with the foreseeable exponential increase in digital morphological data. Reviewers This article was reviewed by Marc D. Sutton (nominated by Stephan Beck), Gonzalo Giribet (nominated by Lutz Walter), and Lennart Olsson (nominated by Purificación López-García). PMID:20604956

Notions of Technology and Visual Literacy

ERIC Educational Resources Information Center

Stankiewicz, Mary Ann

2004-01-01

For many art educators, the word "technology" conjures up visions of overhead projectors and VCRs, video and digital cameras, computers equipped with graphic programs and presentation software, digital labs where images rendered in pixels replace the debris of charcoal dust and puddled paints. One forgets that visual literacy and technology have…

Fuzzy Intervals for Designing Structural Signature: An Application to Graphic Symbol Recognition

NASA Astrophysics Data System (ADS)

Luqman, Muhammad Muzzamil; Delalandre, Mathieu; Brouard, Thierry; Ramel, Jean-Yves; Lladós, Josep

The motivation behind our work is to present a new methodology for symbol recognition. The proposed method employs a structural approach for representing visual associations in symbols and a statistical classifier for recognition. We vectorize a graphic symbol, encode its topological and geometrical information by an attributed relational graph and compute a signature from this structural graph. We have addressed the sensitivity of structural representations to noise, by using data adapted fuzzy intervals. The joint probability distribution of signatures is encoded by a Bayesian network, which serves as a mechanism for pruning irrelevant features and choosing a subset of interesting features from structural signatures of underlying symbol set. The Bayesian network is deployed in a supervised learning scenario for recognizing query symbols. The method has been evaluated for robustness against degradations & deformations on pre-segmented 2D linear architectural & electronic symbols from GREC databases, and for its recognition abilities on symbols with context noise i.e. cropped symbols.

Design and application of BIM based digital sand table for construction management

NASA Astrophysics Data System (ADS)

Fuquan, JI; Jianqiang, LI; Weijia, LIU

2018-05-01

This paper explores the design and application of BIM based digital sand table for construction management. Aiming at the demands and features of construction management plan for bridge and tunnel engineering, the key functional features of digital sand table should include three-dimensional GIS, model navigation, virtual simulation, information layers, and data exchange, etc. That involving the technology of 3D visualization and 4D virtual simulation of BIM, breakdown structure of BIM model and project data, multi-dimensional information layers, and multi-source data acquisition and interaction. Totally, the digital sand table is a visual and virtual engineering information integrated terminal, under the unified data standard system. Also, the applications shall contain visual constructing scheme, virtual constructing schedule, and monitoring of construction, etc. Finally, the applicability of several basic software to the digital sand table is analyzed.

Theoretical Characterization of Visual Signatures and Calculation of Approximate Global Harmonic Frequency Scaling Factors

NASA Astrophysics Data System (ADS)

Kashinski, D. O.; Nelson, R. G.; Chase, G. M.; di Nallo, O. E.; Byrd, E. F. C.

2016-05-01

We are investigating the accuracy of theoretical models used to predict the visible, ultraviolet, and infrared spectra, as well as other properties, of product materials ejected from the muzzle of currently fielded systems. Recent advances in solid propellants has made the management of muzzle signature (flash) a principle issue in weapons development across the calibers. A priori prediction of the electromagnetic spectra of formulations will allow researchers to tailor blends that yield desired signatures and determine spectrographic detection ranges. Quantum chemistry methods at various levels of sophistication have been employed to optimize molecular geometries, compute unscaled harmonic frequencies, and determine the optical spectra of specific gas-phase species. Electronic excitations are being computed using Time Dependent Density Functional Theory (TD-DFT). Calculation of approximate global harmonic frequency scaling factors for specific DFT functionals is also in progress. A full statistical analysis and reliability assessment of computational results is currently underway. Work supported by the ARL, DoD-HPCMP, and USMA.

Design of an aid to visual inspection workstation

NASA Astrophysics Data System (ADS)

Tait, Robert; Harding, Kevin

2016-05-01

Visual Inspection is the most common means for inspecting manufactured parts for random defects such as pits, scratches, breaks, corrosion or general wear. The reason for the need for visual inspection is the very random nature of what might be a defect. Some defects may be very rare, being seen once or twice a year, but May still be critical to part performance. Because of this random and rare nature, even the most sophisticated image analysis programs have not been able to recognize all possible defects. Key to any future automation of inspection is obtaining good sample images of what might be a defect. However, most visual check take no images and consequently generate no digital data or historical record beyond a simple count. Any additional tool to captures such images must be able to do so without taking addition time. This paper outlines the design of a potential visual inspection station that would be compatible with current visual inspection methods, but afford the means for reliable digital imaging and in many cases augmented capabilities to assist the inspection. Considerations in this study included: resolution, depth of field, feature highlighting, and ease of digital capture, annotations and inspection augmentation for repeatable registration as well as operator assistance and training.

Direct modeling parameter signature analysis and failure mode prediction of physical systems using hybrid computer optimization

NASA Technical Reports Server (NTRS)

Drake, R. L.; Duvoisin, P. F.; Asthana, A.; Mather, T. W.

1971-01-01

High speed automated identification and design of dynamic systems, both linear and nonlinear, are discussed. Special emphasis is placed on developing hardware and techniques which are applicable to practical problems. The basic modeling experiment and new results are described. Using the improvements developed successful identification of several systems, including a physical example as well as simulated systems, was obtained. The advantages of parameter signature analysis over signal signature analysis in go-no go testing of operational systems were demonstrated. The feasibility of using these ideas in failure mode prediction in operating systems was also investigated. An improved digital controlled nonlinear function generator was developed, de-bugged, and completely documented.

Pose-oblivious shape signature.

PubMed

Gal, Ran; Shamir, Ariel; Cohen-Or, Daniel

2007-01-01

A 3D shape signature is a compact representation for some essence of a shape. Shape signatures are commonly utilized as a fast indexing mechanism for shape retrieval. Effective shape signatures capture some global geometric properties which are scale, translation, and rotation invariant. In this paper, we introduce an effective shape signature which is also pose-oblivious. This means that the signature is also insensitive to transformations which change the pose of a 3D shape such as skeletal articulations. Although some topology-based matching methods can be considered pose-oblivious as well, our new signature retains the simplicity and speed of signature indexing. Moreover, contrary to topology-based methods, the new signature is also insensitive to the topology change of the shape, allowing us to match similar shapes with different genus. Our shape signature is a 2D histogram which is a combination of the distribution of two scalar functions defined on the boundary surface of the 3D shape. The first is a definition of a novel function called the local-diameter function. This function measures the diameter of the 3D shape in the neighborhood of each vertex. The histogram of this function is an informative measure of the shape which is insensitive to pose changes. The second is the centricity function that measures the average geodesic distance from one vertex to all other vertices on the mesh. We evaluate and compare a number of methods for measuring the similarity between two signatures, and demonstrate the effectiveness of our pose-oblivious shape signature within a 3D search engine application for different databases containing hundreds of models.

Colour in digital pathology: a review.

PubMed

Clarke, Emily L; Treanor, Darren

2017-01-01

Colour is central to the practice of pathology because of the use of coloured histochemical and immunohistochemical stains to visualize tissue features. Our reliance upon histochemical stains and light microscopy has evolved alongside a wide variation in slide colour, with little investigation into the implications of colour variation. However, the introduction of the digital microscope and whole-slide imaging has highlighted the need for further understanding and control of colour. This is because the digitization process itself introduces further colour variation which may affect diagnosis, and image analysis algorithms often use colour or intensity measures to detect or measure tissue features. The US Food and Drug Administration have released recent guidance stating the need to develop a method of controlling colour reproduction throughout the digitization process in whole-slide imaging for primary diagnostic use. This comprehensive review introduces applied basic colour physics and colour interpretation by the human visual system, before discussing the importance of colour in pathology. The process of colour calibration and its application to pathology are also included, as well as a summary of the current guidelines and recommendations regarding colour in digital pathology. © 2016 John Wiley & Sons Ltd.

User-Driven Planning for Digital-Image Delivery

ERIC Educational Resources Information Center

Pisciotta, Henry; Halm, Michael J.; Dooris, Michael J.

2006-01-01

This article draws on two projects funded by the Andrew W. Mellon Foundation concerning the ways colleges and universities can support the legitimate sharing of digital learning resources for scholarly use. The 2001-03 Visual Image User Study (VIUS) assessed the scholarly needs of digital image users-faculty, staff, and students. That study led to…

Impact of Digital Tooth Preparation Evaluation Technology on Preclinical Dental Students' Technical and Self-Evaluation Skills.

PubMed

Gratton, David G; Kwon, So Ran; Blanchette, Derek; Aquilino, Steven A

2016-01-01

The aim of this study was to evaluate the effect of digital tooth preparation imaging and evaluation technology on dental students' technical abilities, self-evaluation skills, and the assessment of their simulated clinical work. A total of 80 second-year students at one U.S. dental school were assigned to one of three groups: control (n=40), E4D Compare (n=20), and Sirona prepCheck (n=20). Students in the control group were taught by traditional teaching methodologies, and the technology-assisted groups received both traditional training and supplementary feedback from the corresponding digital system. Three outcomes were measured: faculty technical score, self-evaluation score, and E4D Compare scores at 0.30 mm tolerance. Correlations were determined between the groups' scores from visual assessment and self-evaluation and between the visual assessment and digital scores. The results showed that the visual assessment and self-evaluation scores did not differ among groups (p>0.05). Overall, correlations between visual and digital assessment scores were modest though statistically significant (5% level of significance). These results suggest that the use of digital tooth preparation evaluation technology did not impact the students' prosthodontic technical and self-evaluation skills. Visual scores given by faculty and digital assessment scores correlated moderately in only two instances.

Digital Education Governance: Data Visualization, Predictive Analytics, and "Real-Time" Policy Instruments

ERIC Educational Resources Information Center

Williamson, Ben

2016-01-01

Educational institutions and governing practices are increasingly augmented with digital database technologies that function as new kinds of policy instruments. This article surveys and maps the landscape of digital policy instrumentation in education and provides two detailed case studies of new digital data systems. The Learning Curve is a…

Visual Communications And Image Processing

NASA Astrophysics Data System (ADS)

Hsing, T. Russell; Tzou, Kou-Hu

1989-07-01

This special issue on Visual Communications and Image Processing contains 14 papers that cover a wide spectrum in this fast growing area. For the past few decades, researchers and scientists have devoted their efforts to these fields. Through this long-lasting devotion, we witness today the growing popularity of low-bit-rate video as a convenient tool for visual communication. We also see the integration of high-quality video into broadband digital networks. Today, with more sophisticated processing, clearer and sharper pictures are being restored from blurring and noise. Also, thanks to the advances in digital image processing, even a PC-based system can be built to recognize highly complicated Chinese characters at the speed of 300 characters per minute. This special issue can be viewed as a milestone of visual communications and image processing on its journey to eternity. It presents some overviews on advanced topics as well as some new development in specific subjects.

Reading Digital with Low Vision

PubMed Central

Legge, Gordon E.

2017-01-01

Reading difficulty is a major consequence of vision loss for more than four million Americans with low vision. Difficulty in accessing print imposes obstacles to education, employment, social interaction and recreation. In recent years, research in vision science has made major strides in understanding the impact of low vision on reading, and the dependence of reading performance on text properties. The ongoing transition to the production and distribution of digital documents brings about new opportunities for people with visual impairment. Digital documents on computers and mobile devices permit customization of print size, spacing, font style, contrast polarity and page layout to optimize reading displays for people with low vision. As a result, we now have unprecedented opportunities to adapt text format to meet the needs of visually impaired readers. PMID:29242668

How digital design shapes political participation: A natural experiment with social information.

PubMed

Hale, Scott A; John, Peter; Margetts, Helen; Yasseri, Taha

2018-01-01

Political behaviour increasingly takes place on digital platforms, where people are presented with a range of social information-real-time feedback about the behaviour of peers and reference groups-which can stimulate (or depress) participation. This social information is hypothesized to impact the distribution of political activity, stimulating participation in mobilizations that are increasing in popularity, and depressing participation in those that appear to be less popular, leading to a non-normal distribution. Changes to these platforms can generate natural experiments allowing for an estimate of the impact of different kinds of social information on participation. This paper tests the hypothesis that social information shapes the distribution of political mobilizations by examining the introduction of trending information to the homepage of the UK government petition platform. The introduction of the trending feature did not increase the overall number of signatures per day, but the distribution of signatures across petitions changed significantly-the most popular petitions gained more signatures at the expense of those with fewer signatories. We further find significant differences between petitions trending at different ranks on the homepage. This evidence suggests that the ubiquity of trending information on digital platforms is introducing instability into political markets, as has been shown for cultural markets. As well as highlighting the importance of digital design in shaping political behaviour, the findings suggest that a non-negligible group of individuals visit the homepage of the site looking for petitions to sign, without having decided the issues they wish to support in advance. These 'aimless petitioners' are particularly susceptible to changes in social information.

A temporal comparison of forest cover using digital earth science data and visualization techniques

USGS Publications Warehouse

Jones, John W.

1993-01-01

Increased demands on forest resources and the recognition of old-growth forests as critical habitats and purifiers of the atmosphere have stimulated attention to forest harvest practices in the United States and worldwide. Visualization technology provides a means by which a history of forestry activities may be documented and presented to the public and decisionmakers. In this project, landsat multispectral scanner and thematic mapper images, acquired July 7, 1981, and July 8, 1991, respectively, were georeferenced, resampled, enhanced, and draped over U.S. Geological Survey 30-meter digital elevation models. These data then were used to create perspective views of portions of Mt. Hood Forest, Oregon. The "fly-by" animation (produced by rapidly displaying a sequence of these perspective views) conveys the forest cover change resulting from forest harvest activities over the 10-year period. This project shows the value of combining satellite data with base cartographic data and earth science information for use in public education and decision-making processes.

Laser-based volumetric flow visualization by digital color imaging of a spectrally coded volume.

PubMed

McGregor, T J; Spence, D J; Coutts, D W

2008-01-01

We present the framework for volumetric laser-based flow visualization instrumentation using a spectrally coded volume to achieve three-component three-dimensional particle velocimetry. By delivering light from a frequency doubled Nd:YAG laser with an optical fiber, we exploit stimulated Raman scattering within the fiber to generate a continuum spanning the visible spectrum from 500 to 850 nm. We shape and disperse the continuum light to illuminate a measurement volume of 20 x 10 x 4 mm(3), in which light sheets of differing spectral properties overlap to form an unambiguous color variation along the depth direction. Using a digital color camera we obtain images of particle fields in this volume. We extract the full spatial distribution of particles with depth inferred from particle color. This paper provides a proof of principle of this instrument, examining the spatial distribution of a static field and a spray field of water droplets ejected by the nozzle of an airbrush.

Evaluation of an Innovative Digital Assessment Tool in Dental Anatomy.

PubMed

Lam, Matt T; Kwon, So Ran; Qian, Fang; Denehy, Gerald E

2015-05-01

The E4D Compare software is an innovative tool that provides immediate feedback to students' projects and competencies. It should provide consistent scores even when different scanners are used which may have inherent subtle differences in calibration. This study aimed to evaluate potential discrepancies in evaluation using the E4D Compare software based on four different NEVO scanners in dental anatomy projects. Additionally, correlation between digital and visual scores was evaluated. Thirty-five projects of maxillary left central incisors were evaluated. Among these, thirty wax-ups were performed by four operators and five consisted of standard dentoform teeth. Five scores were obtained for each project: one from an instructor that visually graded the project and from four different NEVO scanners. A faculty involved in teaching the dental anatomy course blindly scored the 35 projects. One operator scanned all projects to four NEVO scanners (D4D Technologies, Richardson, TX, USA). The images were aligned to the gold standard, and tolerance set at 0.3 mm to generate a score. The score reflected percentage match between the project and the gold standard. One-way ANOVA with repeated measures was used to determine whether there was a significant difference in scores among the four NEVO scanners. Paired-sample t-test was used to detect any difference between visual scores and the average scores of the four NEVO scanners. Pearson's correlation test was used to assess the relationship between visual and average scores of NEVO scanners. There was no significant difference in mean scores among four different NEVO scanners [F(3, 102) = 2.27, p = 0.0852 one-way ANOVA with repeated measures]. Moreover, the data provided strong evidence that a significant difference existed between visual and digital scores (p = 0.0217; a paired - sample t-test). Mean visual scores were significantly lower than digital scores (72.4 vs 75.1). Pearson's correlation coefficient of 0.85 indicated

Unconditionally Secure Blind Signatures

NASA Astrophysics Data System (ADS)

Hara, Yuki; Seito, Takenobu; Shikata, Junji; Matsumoto, Tsutomu

The blind signature scheme introduced by Chaum allows a user to obtain a valid signature for a message from a signer such that the message is kept secret for the signer. Blind signature schemes have mainly been studied from a viewpoint of computational security so far. In this paper, we study blind signatures in unconditional setting. Specifically, we newly introduce a model of unconditionally secure blind signature schemes (USBS, for short). Also, we propose security notions and their formalization in our model. Finally, we propose a construction method for USBS that is provably secure in our security notions.

Two-dimensional analysis of palpebral opening in blepharoptosis: visual iris-pupil complex percentage by digital photography.

PubMed

Choi, Yeop; Eo, SuRak

2014-04-01

The vertical dimension of the palpebral fissure and the marginal reflex distance are conventionally used to assess the amount or degree of blepharoptosis, and levator function is assessed by measuring total upper lid excursion between the extremes of down-gaze and up-gaze. However, these are 1-dimensional measures obtained with a ruler, and the results obtained are dependent on examiner skill. Digital photographs were obtained of 692 patients before and after upper blepharoplasty. Visual iris-pupil complex percentage (VIP) was measured in the 1,305 eyes by digital calculation using Adobe Photoshop CS3 (Adobe Systems, Inc). Perioperative eye images in primary gaze were evaluated independently by 2 surgeons, 2 nurses, and a graphic designer, and after excluding 50 eyes which were nonconcordant and 29 eyes which revealed retracted upper lids, the remaining 1,305 eyes were classified into 4 major groups, that is, into excellent (n = 415), good (n = 435), subclinical (n = 270), and prominent ptosis (n = 185) groups. In addition, eyes were subdivided into 5 types according to the iris-pupil complex position within the palpebral fissure. Visual iris-pupil complex percentages were from 85% to 94% in the excellent, from 78% to 84% in the good, from 70% to 77% in the subclinical ptosis, and below 70% in the prominent ptosis group. Patients in the subclinical or prominent ptosis eye group required surgery for blepharoptosis. Iris-pupil complex relation to the palpebral opening was classified into 5 eye types, namely, standard (n = 961), scleral (n = 266), sinking (n = 151), retracted (n = 3), and fish (n = 3). The authors devised a new prospective measurement method for assessing blepharoptosis in a clinical setting. Graphical comparisons between the devised method of measuring VIP and mathematical estimations showed that the devised method is easier, more practical, and more precise for measuring degree of blepharoptosis from general population trends, and that VIP also

Visual Stereotypes and Virtual Pedagogical Agents

ERIC Educational Resources Information Center

Haake, Magnus; Gulz, Agneta

2008-01-01

The paper deals with the use of visual stereotypes in virtual pedagogical agents and its potential impact in digital learning environments. An analysis of the concept of visual stereotypes is followed by a discussion of affordances and drawbacks as to their use in the context of traditional media. Next, the paper explores whether virtual…

Variability of Grip Kinetics during Adult Signature Writing

PubMed Central

Ghali, Bassma; Thalanki Anantha, Nayanashri; Chan, Jennifer; Chau, Tom

2013-01-01

Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20) adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image) was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC) of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height) or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of % in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively. PMID:23658812

Variability of grip kinetics during adult signature writing.

PubMed

Ghali, Bassma; Thalanki Anantha, Nayanashri; Chan, Jennifer; Chau, Tom

2013-01-01

Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20) adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image) was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC) of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height) or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of 1.2±0.4% in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.

Factor models for cancer signatures

NASA Astrophysics Data System (ADS)

Kakushadze, Zura; Yu, Willie

2016-11-01

We present a novel method for extracting cancer signatures by applying statistical risk models (http://ssrn.com/abstract=2732453) from quantitative finance to cancer genome data. Using 1389 whole genome sequenced samples from 14 cancers, we identify an ;overall; mode of somatic mutational noise. We give a prescription for factoring out this noise and source code for fixing the number of signatures. We apply nonnegative matrix factorization (NMF) to genome data aggregated by cancer subtype and filtered using our method. The resultant signatures have substantially lower variability than those from unfiltered data. Also, the computational cost of signature extraction is cut by about a factor of 10. We find 3 novel cancer signatures, including a liver cancer dominant signature (96% contribution) and a renal cell carcinoma signature (70% contribution). Our method accelerates finding new cancer signatures and improves their overall stability. Reciprocally, the methods for extracting cancer signatures could have interesting applications in quantitative finance.

Computerized digital dermoscopy.

PubMed

Gewirtzman, A J; Braun, R P

2003-01-01

Within the past 15 years, dermoscopy has become a widely used non-invasive technique for physicians to better visualize pigmented lesions. Dermoscopy has helped trained physicians to better diagnose pigmented lesions. Now, the digital revolution is beginning to enhance standard dermoscopic procedures. Using digital dermoscopy, physicians are better able to document pigmented lesions for patient follow-up and to get second opinions, either through teledermoscopy with an expert colleague or by using computer-assisted diagnosis. As the market for digital dermoscopy products begins to grow, so do the number of decisions physicians need to make when choosing a system to fit their needs. The current market for digital dermoscopy includes two varieties of relatively simple and cheap attachments which can convert a consumer digital camera into a digital dermoscope. A coupling adapter acts as a fastener between the camera and an ordinary dermoscope, whereas a dermoscopy attachment includes the dermoscope optics and light source and can be attached directly to the camera. Other options for digital dermoscopy include complete dermoscopy systems that use a hand-held video camera linked directly to a computer. These systems differ from each other in whether or not they are calibrated as well as the quality of the camera and software interface. Another option in digital skin imaging involves spectral analysis rather than dermoscopy. This article serves as a guide to the current systems available and their capabilities.

Digital pathology in nephrology clinical trials, research, and pathology practice.

PubMed

Barisoni, Laura; Hodgin, Jeffrey B

2017-11-01

In this review, we will discuss (i) how the recent advancements in digital technology and computational engineering are currently applied to nephropathology in the setting of clinical research, trials, and practice; (ii) the benefits of the new digital environment; (iii) how recognizing its challenges provides opportunities for transformation; and (iv) nephropathology in the upcoming era of kidney precision and predictive medicine. Recent studies highlighted how new standardized protocols facilitate the harmonization of digital pathology database infrastructure and morphologic, morphometric, and computer-aided quantitative analyses. Digital pathology enables robust protocols for clinical trials and research, with the potential to identify previously underused or unrecognized clinically useful parameters. The integration of digital pathology with molecular signatures is leading the way to establishing clinically relevant morpho-omic taxonomies of renal diseases. The introduction of digital pathology in clinical research and trials, and the progressive implementation of the modern software ecosystem, opens opportunities for the development of new predictive diagnostic paradigms and computer-aided algorithms, transforming the practice of renal disease into a modern computational science.

Categorically Defined Targets Trigger Spatiotemporal Visual Attention

ERIC Educational Resources Information Center

Wyble, Brad; Bowman, Howard; Potter, Mary C.

2009-01-01

Transient attention to a visually salient cue enhances processing of a subsequent target in the same spatial location between 50 to 150 ms after cue onset (K. Nakayama & M. Mackeben, 1989). Do stimuli from a categorically defined target set, such as letters or digits, also generate transient attention? Participants reported digit targets among…

Optical spectral signatures of liquids by means of fiber optic technology for product and quality parameter identification

NASA Astrophysics Data System (ADS)

Mignani, A. G.; Ciaccheri, L.; Mencaglia, A. A.; Diaz-Herrera, N.; Garcia-Allende, P. B.; Ottevaere, H.; Thienpont, H.; Attilio, C.; Cimato, A.; Francalanci, S.; Paccagnini, A.; Pavone, F. S.

2009-01-01

Absorption spectroscopy in the wide 200-1700 nm spectral range is carried out by means of optical fiber instrumentation to achieve a digital mapping of liquids for the prediction of important quality parameters. Extra virgin olive oils from Italy and lubricant oils from turbines with different degrees of degradation were considered as "case studies". The spectral data were processed by means of multivariate analysis so as to obtain a correlation to quality parameters. In practice, the wide range absorption spectra were considered as an optical signature of the liquids from which to extract product quality information. The optical signatures of extra virgin olive oils were used to predict the content of the most important fatty acids. The optical signatures of lubricant oils were used to predict the concentration of the most important parameters for indicating the oil's degree of degradation, such as TAN, JOAP anti-wear index, and water content.

Data mining and visualization of average images in a digital hand atlas

NASA Astrophysics Data System (ADS)

Zhang, Aifeng; Gertych, Arkadiusz; Liu, Brent J.; Huang, H. K.

2005-04-01

We have collected a digital hand atlas containing digitized left hand radiographs of normally developed children grouped accordingly by age, sex, and race. A set of features stored in a database reflecting patient's stage of skeletal development has been calculated by automatic image processing procedures. This paper addresses a new concept, "average" image in the digital hand atlas. The "average" reference image in the digital atlas is selected for each of the groups of normal developed children with the best representative skeletal maturity based on bony features. A data mining procedure was designed and applied to find the average image through average feature vector matching. It also provides a temporary solution for the missing feature problem through polynomial regression. As more cases are added to the digital hand atlas, it can grow to provide clinicians accurate reference images to aid the bone age assessment process.

Digitized forensics: retaining a link between physical and digital crime scene traces using QR-codes

NASA Astrophysics Data System (ADS)

Hildebrandt, Mario; Kiltz, Stefan; Dittmann, Jana

2013-03-01

The digitization of physical traces from crime scenes in forensic investigations in effect creates a digital chain-of-custody and entrains the challenge of creating a link between the two or more representations of the same trace. In order to be forensically sound, especially the two security aspects of integrity and authenticity need to be maintained at all times. Especially the adherence to the authenticity using technical means proves to be a challenge at the boundary between the physical object and its digital representations. In this article we propose a new method of linking physical objects with its digital counterparts using two-dimensional bar codes and additional meta-data accompanying the acquired data for integration in the conventional documentation of collection of items of evidence (bagging and tagging process). Using the exemplary chosen QR-code as particular implementation of a bar code and a model of the forensic process, we also supply a means to integrate our suggested approach into forensically sound proceedings as described by Holder et al.1 We use the example of the digital dactyloscopy as a forensic discipline, where currently progress is being made by digitizing some of the processing steps. We show an exemplary demonstrator of the suggested approach using a smartphone as a mobile device for the verification of the physical trace to extend the chain-of-custody from the physical to the digital domain. Our evaluation of the demonstrator is performed towards the readability and the verification of its contents. We can read the bar code despite its limited size of 42 x 42 mm and rather large amount of embedded data using various devices. Furthermore, the QR-code's error correction features help to recover contents of damaged codes. Subsequently, our appended digital signature allows for detecting malicious manipulations of the embedded data.

Electronic Signature Policy

EPA Pesticide Factsheets

Establishes the United States Environmental Protection Agency's approach to adopting electronic signature technology and best practices to ensure electronic signatures applied to official Agency documents are legally valid and enforceable

Digitizing Patterns of Power - Cartographic Communication for Digital Humanities

NASA Astrophysics Data System (ADS)

Kriz, Karel; Pucher, Alexander; Breier, Markus

2018-05-01

The representation of space in medieval texts, the appropriation of land and the subsequent installation of new structures of power are central research topics of the project "Digitizing Patterns of Power" (DPP). The project focuses on three regional case studies: the Eastern Alps and the Morava-Thaya region, the historical region of Macedonia, and historical Southern Armenia. DPP is a multidisciplinary project, conducted by the Austrian Academy of Sciences the Institute for Medieval Research (IMAFO) in cooperation with the University of Vienna, Department of Geography and Regional Research. It is part of an initiative to promote digital humanities research in Austria. DPP brings together expertise from historical and archaeological research as well as cartography and geocommunication to explore medieval geographies. The communication of space, time and spatial interconnectivity is an essential aspect of DPP. By incorporating digital cartographic expertise, relevant facts can be depicted in a more effective visual form. Optimal cartographic visualization of base data as well as the historical and archaeological information in an interactive map-based online platform are important features. However, the multidisciplinary of the project presents the participants with various challenges. The different involved disciplines, among them cartography, archaeology and history each have their own approaches to relevant aspects of geography and geocommunication. This paper treats geocommunication characteristics and approaches to interactive mapping in a historical and archaeological context within a multidisciplinary project environment. The fundamental challenges of cartographic communication within DPP will be presented. Furthermore, recent results on the communication of historical topographic, as well as uncertain thematic content will be demonstrated.

An archaeal genomic signature

NASA Technical Reports Server (NTRS)

Graham, D. E.; Overbeek, R.; Olsen, G. J.; Woese, C. R.

2000-01-01

Comparisons of complete genome sequences allow the most objective and comprehensive descriptions possible of a lineage's evolution. This communication uses the completed genomes from four major euryarchaeal taxa to define a genomic signature for the Euryarchaeota and, by extension, the Archaea as a whole. The signature is defined in terms of the set of protein-encoding genes found in at least two diverse members of the euryarchaeal taxa that function uniquely within the Archaea; most signature proteins have no recognizable bacterial or eukaryal homologs. By this definition, 351 clusters of signature proteins have been identified. Functions of most proteins in this signature set are currently unknown. At least 70% of the clusters that contain proteins from all the euryarchaeal genomes also have crenarchaeal homologs. This conservative set, which appears refractory to horizontal gene transfer to the Bacteria or the Eukarya, would seem to reflect the significant innovations that were unique and fundamental to the archaeal "design fabric." Genomic protein signature analysis methods may be extended to characterize the evolution of any phylogenetically defined lineage. The complete set of protein clusters for the archaeal genomic signature is presented as supplementary material (see the PNAS web site, www.pnas.org).

Assessment of visual communication by information theory

NASA Astrophysics Data System (ADS)

Huck, Friedrich O.; Fales, Carl L.

1994-01-01

This assessment of visual communication integrates the optical design of the image-gathering device with the digital processing for image coding and restoration. Results show that informationally optimized image gathering ordinarily can be relied upon to maximize the information efficiency of decorrelated data and the visual quality of optimally restored images.

Visualizing the Diffusion of Digital Mammography in New York State.

PubMed

Boscoe, Francis P; Zhang, Xiuling

2017-04-01

Background: Digital mammography saw rapid adoption during the first decade of the 2000s. We were interested in identifying the times and locations where the technology was introduced within the state of New York as a way of illustrating the uneven introduction of this technology. Methods: Using a sample of Medicare claims data from the period 2004 to 2012 from women ages 65 and over without cancer, we calculated the percentage of mammograms that were digital by zip code of residence and illustrated them with a series of smoothed maps. Results: Maps for three of the years (2005, 2008, and 2011) show the conversion from almost no digital mammography to nearly all digital mammography. The 2008 map reveals sharp disparities between areas that had and had not yet adopted the technology. Socioeconomic differences explain some of this pattern. Conclusions: Geographic disparities in access to medical technology are underappreciated relative to other sources of disparities. Our method provides a way of measuring and communicating this phenomenon. Impact: Our method could be applied to illuminate current examples, where access to medical technology is highly uneven, such as 3D tomography and robotic surgery. Cancer Epidemiol Biomarkers Prev; 26(4); 490-4. ©2017 AACR See all the articles in this CEBP Focus section, "Geospatial Approaches to Cancer Control and Population Sciences." ©2017 American Association for Cancer Research.

1 CFR 18.7 - Signature.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 1 General Provisions 1 2010-01-01 2010-01-01 false Signature. 18.7 Section 18.7 General Provisions... PREPARATION AND TRANSMITTAL OF DOCUMENTS GENERALLY § 18.7 Signature. The original and each duplicate original... stamped beneath the signature. Initialed or impressed signatures will not be accepted. Documents submitted...

How digital design shapes political participation: A natural experiment with social information

PubMed Central

John, Peter; Margetts, Helen; Yasseri, Taha

2018-01-01

Political behaviour increasingly takes place on digital platforms, where people are presented with a range of social information—real-time feedback about the behaviour of peers and reference groups—which can stimulate (or depress) participation. This social information is hypothesized to impact the distribution of political activity, stimulating participation in mobilizations that are increasing in popularity, and depressing participation in those that appear to be less popular, leading to a non-normal distribution. Changes to these platforms can generate natural experiments allowing for an estimate of the impact of different kinds of social information on participation. This paper tests the hypothesis that social information shapes the distribution of political mobilizations by examining the introduction of trending information to the homepage of the UK government petition platform. The introduction of the trending feature did not increase the overall number of signatures per day, but the distribution of signatures across petitions changed significantly—the most popular petitions gained more signatures at the expense of those with fewer signatories. We further find significant differences between petitions trending at different ranks on the homepage. This evidence suggests that the ubiquity of trending information on digital platforms is introducing instability into political markets, as has been shown for cultural markets. As well as highlighting the importance of digital design in shaping political behaviour, the findings suggest that a non-negligible group of individuals visit the homepage of the site looking for petitions to sign, without having decided the issues they wish to support in advance. These ‘aimless petitioners’ are particularly susceptible to changes in social information. PMID:29702664

Spatial and Temporal Signatures of Flux Transfer Events in Global Simulations of Magnetopause Dynamics

NASA Technical Reports Server (NTRS)

Kuznetsova, Maria M.; Sibeck, David Gary; Hesse, Michael; Berrios, David; Rastaetter, Lutz; Toth, Gabor; Gombosi, Tamas I.

2011-01-01

Flux transfer events (FTEs) were originally identified by transient bipolar variations of the magnetic field component normal to the nominal magnetopause centered on enhancements in the total magnetic field strength. Recent Cluster and THEMIS multi-point measurements provided a wide range of signatures that are interpreted as evidence for FTE passage (e.g., crater FTE's, traveling magnetic erosion regions). We use the global magnetohydrodynamic (MHD) code BATS-R-US developed at the University of Michigan to model the global three-dimensional structure and temporal evolution of FTEs during multi-spacecraft magnetopause crossing events. Comparison of observed and simulated signatures and sensitivity analysis of the results to the probe location will be presented. We will demonstrate a variety of observable signatures in magnetic field profile that depend on space probe location with respect to the FTE passage. The global structure of FTEs will be illustrated using advanced visualization tools developed at the Community Coordinated Modeling Center

Steady-state signatures of visual perceptual load, multimodal distractor filtering, and neural competition.

PubMed

Parks, Nathan A; Hilimire, Matthew R; Corballis, Paul M

2011-05-01

The perceptual load theory of attention posits that attentional selection occurs early in processing when a task is perceptually demanding but occurs late in processing otherwise. We used a frequency-tagged steady-state evoked potential paradigm to investigate the modality specificity of perceptual load-induced distractor filtering and the nature of neural-competitive interactions between task and distractor stimuli. EEG data were recorded while participants monitored a stream of stimuli occurring in rapid serial visual presentation (RSVP) for the appearance of previously assigned targets. Perceptual load was manipulated by assigning targets that were identifiable by color alone (low load) or by the conjunction of color and orientation (high load). The RSVP task was performed alone and in the presence of task-irrelevant visual and auditory distractors. The RSVP stimuli, visual distractors, and auditory distractors were "tagged" by modulating each at a unique frequency (2.5, 8.5, and 40.0 Hz, respectively), which allowed each to be analyzed separately in the frequency domain. We report three important findings regarding the neural mechanisms of perceptual load. First, we replicated previous findings of within-modality distractor filtering and demonstrated a reduction in visual distractor signals with high perceptual load. Second, auditory steady-state distractor signals were unaffected by manipulations of visual perceptual load, consistent with the idea that perceptual load-induced distractor filtering is modality specific. Third, analysis of task-related signals revealed that visual distractors competed with task stimuli for representation and that increased perceptual load appeared to resolve this competition in favor of the task stimulus.

Visualization of JPEG Metadata

NASA Astrophysics Data System (ADS)

Malik Mohamad, Kamaruddin; Deris, Mustafa Mat

There are a lot of information embedded in JPEG image than just graphics. Visualization of its metadata would benefit digital forensic investigator to view embedded data including corrupted image where no graphics can be displayed in order to assist in evidence collection for cases such as child pornography or steganography. There are already available tools such as metadata readers, editors and extraction tools but mostly focusing on visualizing attribute information of JPEG Exif. However, none have been done to visualize metadata by consolidating markers summary, header structure, Huffman table and quantization table in a single program. In this paper, metadata visualization is done by developing a program that able to summarize all existing markers, header structure, Huffman table and quantization table in JPEG. The result shows that visualization of metadata helps viewing the hidden information within JPEG more easily.

Development of an automatic cow body condition scoring using body shape signature and Fourier descriptors.

PubMed

Bercovich, A; Edan, Y; Alchanatis, V; Moallem, U; Parmet, Y; Honig, H; Maltz, E; Antler, A; Halachmi, I

2013-01-01

Body condition evaluation is a common tool to assess energy reserves of dairy cows and to estimate their fatness or thinness. This study presents a computer-vision tool that automatically estimates cow's body condition score. Top-view images of 151 cows were collected on an Israeli research dairy farm using a digital still camera located at the entrance to the milking parlor. The cow's tailhead area and its contour were segmented and extracted automatically. Two types of features of the tailhead contour were extracted: (1) the angles and distances between 5 anatomical points; and (2) the cow signature, which is a 1-dimensional vector of the Euclidean distances from each point in the normalized tailhead contour to the shape center. Two methods were applied to describe the cow's signature and to reduce its dimension: (1) partial least squares regression, and (2) Fourier descriptors of the cow signature. Three prediction models were compared with manual scores of an expert. Results indicate that (1) it is possible to automatically extract and predict body condition from color images without any manual interference; and (2) Fourier descriptors of the cow's signature result in improved performance (R(2)=0.77). Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

a Novel Ship Detection Method for Large-Scale Optical Satellite Images Based on Visual Lbp Feature and Visual Attention Model

NASA Astrophysics Data System (ADS)

Haigang, Sui; Zhina, Song

2016-06-01

Reliably ship detection in optical satellite images has a wide application in both military and civil fields. However, this problem is very difficult in complex backgrounds, such as waves, clouds, and small islands. Aiming at these issues, this paper explores an automatic and robust model for ship detection in large-scale optical satellite images, which relies on detecting statistical signatures of ship targets, in terms of biologically-inspired visual features. This model first selects salient candidate regions across large-scale images by using a mechanism based on biologically-inspired visual features, combined with visual attention model with local binary pattern (CVLBP). Different from traditional studies, the proposed algorithm is high-speed and helpful to focus on the suspected ship areas avoiding the separation step of land and sea. Largearea images are cut into small image chips and analyzed in two complementary ways: Sparse saliency using visual attention model and detail signatures using LBP features, thus accordant with sparseness of ship distribution on images. Then these features are employed to classify each chip as containing ship targets or not, using a support vector machine (SVM). After getting the suspicious areas, there are still some false alarms such as microwaves and small ribbon clouds, thus simple shape and texture analysis are adopted to distinguish between ships and nonships in suspicious areas. Experimental results show the proposed method is insensitive to waves, clouds, illumination and ship size.

A method for automatically abstracting visual documents

NASA Technical Reports Server (NTRS)

Rorvig, Mark E.

1994-01-01

Visual documents--motion sequences on film, videotape, and digital recording--constitute a major source of information for the Space Agency, as well as all other government and private sector entities. This article describes a method for automatically selecting key frames from visual documents. These frames may in turn be used to represent the total image sequence of visual documents in visual libraries, hypermedia systems, and training algorithm reduces 51 minutes of video sequences to 134 frames; a reduction of information in the range of 700:1.

Simulating realistic predator signatures in quantitative fatty acid signature analysis

USGS Publications Warehouse

Bromaghin, Jeffrey F.

2015-01-01

Diet estimation is an important field within quantitative ecology, providing critical insights into many aspects of ecology and community dynamics. Quantitative fatty acid signature analysis (QFASA) is a prominent method of diet estimation, particularly for marine mammal and bird species. Investigators using QFASA commonly use computer simulation to evaluate statistical characteristics of diet estimators for the populations they study. Similar computer simulations have been used to explore and compare the performance of different variations of the original QFASA diet estimator. In both cases, computer simulations involve bootstrap sampling prey signature data to construct pseudo-predator signatures with known properties. However, bootstrap sample sizes have been selected arbitrarily and pseudo-predator signatures therefore may not have realistic properties. I develop an algorithm to objectively establish bootstrap sample sizes that generates pseudo-predator signatures with realistic properties, thereby enhancing the utility of computer simulation for assessing QFASA estimator performance. The algorithm also appears to be computationally efficient, resulting in bootstrap sample sizes that are smaller than those commonly used. I illustrate the algorithm with an example using data from Chukchi Sea polar bears (Ursus maritimus) and their marine mammal prey. The concepts underlying the approach may have value in other areas of quantitative ecology in which bootstrap samples are post-processed prior to their use.

Membrane connectivity estimated by digital image analysis of HER2 immunohistochemistry is concordant with visual scoring and fluorescence in situ hybridization results: algorithm evaluation on breast cancer tissue microarrays

PubMed Central

2011-01-01

Introduction The human epidermal growth factor receptor 2 (HER2) is an established biomarker for management of patients with breast cancer. While conventional testing of HER2 protein expression is based on semi-quantitative visual scoring of the immunohistochemistry (IHC) result, efforts to reduce inter-observer variation and to produce continuous estimates of the IHC data are potentiated by digital image analysis technologies. Methods HER2 IHC was performed on the tissue microarrays (TMAs) of 195 patients with an early ductal carcinoma of the breast. Digital images of the IHC slides were obtained by Aperio ScanScope GL Slide Scanner. Membrane connectivity algorithm (HER2-CONNECT™, Visiopharm) was used for digital image analysis (DA). A pathologist evaluated the images on the screen twice (visual evaluations: VE1 and VE2). HER2 fluorescence in situ hybridization (FISH) was performed on the corresponding sections of the TMAs. The agreement between the IHC HER2 scores, obtained by VE1, VE2, and DA was tested for individual TMA spots and patient's maximum TMA spot values (VE1max, VE2max, DAmax). The latter were compared with the FISH data. Correlation of the continuous variable of the membrane connectivity estimate with the FISH data was tested. Results The pathologist intra-observer agreement (VE1 and VE2) on HER2 IHC score was almost perfect: kappa 0.91 (by spot) and 0.88 (by patient). The agreement between visual evaluation and digital image analysis was almost perfect at the spot level (kappa 0.86 and 0.87, with VE1 and VE2 respectively) and at the patient level (kappa 0.80 and 0.86, with VE1max and VE2max, respectively). The DA was more accurate than VE in detection of FISH-positive patients by recruiting 3 or 2 additional FISH-positive patients to the IHC score 2+ category from the IHC 0/1+ category by VE1max or VE2max, respectively. The DA continuous variable of the membrane connectivity correlated with the FISH data (HER2 and CEP17 copy numbers, and HER2/CEP

Membrane connectivity estimated by digital image analysis of HER2 immunohistochemistry is concordant with visual scoring and fluorescence in situ hybridization results: algorithm evaluation on breast cancer tissue microarrays.

PubMed

Laurinaviciene, Aida; Dasevicius, Darius; Ostapenko, Valerijus; Jarmalaite, Sonata; Lazutka, Juozas; Laurinavicius, Arvydas

2011-09-23

The human epidermal growth factor receptor 2 (HER2) is an established biomarker for management of patients with breast cancer. While conventional testing of HER2 protein expression is based on semi-quantitative visual scoring of the immunohistochemistry (IHC) result, efforts to reduce inter-observer variation and to produce continuous estimates of the IHC data are potentiated by digital image analysis technologies. HER2 IHC was performed on the tissue microarrays (TMAs) of 195 patients with an early ductal carcinoma of the breast. Digital images of the IHC slides were obtained by Aperio ScanScope GL Slide Scanner. Membrane connectivity algorithm (HER2-CONNECT, Visiopharm) was used for digital image analysis (DA). A pathologist evaluated the images on the screen twice (visual evaluations: VE1 and VE2). HER2 fluorescence in situ hybridization (FISH) was performed on the corresponding sections of the TMAs. The agreement between the IHC HER2 scores, obtained by VE1, VE2, and DA was tested for individual TMA spots and patient's maximum TMA spot values (VE1max, VE2max, DAmax). The latter were compared with the FISH data. Correlation of the continuous variable of the membrane connectivity estimate with the FISH data was tested. The pathologist intra-observer agreement (VE1 and VE2) on HER2 IHC score was almost perfect: kappa 0.91 (by spot) and 0.88 (by patient). The agreement between visual evaluation and digital image analysis was almost perfect at the spot level (kappa 0.86 and 0.87, with VE1 and VE2 respectively) and at the patient level (kappa 0.80 and 0.86, with VE1max and VE2max, respectively). The DA was more accurate than VE in detection of FISH-positive patients by recruiting 3 or 2 additional FISH-positive patients to the IHC score 2+ category from the IHC 0/1+ category by VE1max or VE2max, respectively. The DA continuous variable of the membrane connectivity correlated with the FISH data (HER2 and CEP17 copy numbers, and HER2/CEP17 ratio). HER2 IHC digital

The effect of non-visual working memory load on top-down modulation of visual processing

PubMed Central

Rissman, Jesse; Gazzaley, Adam; D'Esposito, Mark

2009-01-01

While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of task-relevant and irrelevant visual representations. In our dual-task paradigm, each trial began with the auditory presentation of six random (high load) or sequentially-ordered (low load) digits. Next, two relevant visual stimuli (e.g., faces), presented amongst two temporally interspersed visual distractors (e.g., scenes), were to be encoded and maintained across a 7-sec delay interval, after which memory for the relevant images and digits was probed. When taxed by high load digit maintenance, participants exhibited impaired performance on the visual WM task and a selective failure to attenuate the neural processing of task-irrelevant scene stimuli. The over-processing of distractor scenes under high load was indexed by elevated encoding activity in a scene-selective region-of-interest relative to low load and passive viewing control conditions, as well as by improved long-term recognition memory for these items. In contrast, the load manipulation did not affect participants' ability to upregulate activity in this region when scenes were task-relevant. These results highlight the critical role of domain-general WM resources in the goal-directed regulation of distractor processing. Moreover, the consequences of increased WM load in young adults closely resemble the effects of cognitive aging on distractor filtering [Gazzaley et al., (2005) Nature Neuroscience 8, 1298-1300], suggesting the possibility of a common underlying mechanism. PMID:19397858

Five Guidelines for Selecting Hydrological Signatures

NASA Astrophysics Data System (ADS)

McMillan, H. K.; Westerberg, I.; Branger, F.

2017-12-01

Hydrological signatures are index values derived from observed or modeled series of hydrological data such as rainfall, flow or soil moisture. They are designed to extract relevant information about hydrological behavior, such as to identify dominant processes, and to determine the strength, speed and spatiotemporal variability of the rainfall-runoff response. Hydrological signatures play an important role in model evaluation. They allow us to test whether particular model structures or parameter sets accurately reproduce the runoff generation processes within the watershed of interest. Most modeling studies use a selection of different signatures to capture different aspects of the catchment response, for example evaluating overall flow distribution as well as high and low flow extremes and flow timing. Such studies often choose their own set of signatures, or may borrow subsets of signatures used in multiple other works. The link between signature values and hydrological processes is not always straightforward, leading to uncertainty and variability in hydrologists' signature choices. In this presentation, we aim to encourage a more rigorous approach to hydrological signature selection, which considers the ability of signatures to represent hydrological behavior and underlying processes for the catchment and application in question. To this end, we propose a set of guidelines for selecting hydrological signatures. We describe five criteria that any hydrological signature should conform to: Identifiability, Robustness, Consistency, Representativeness, and Discriminatory Power. We describe an example of the design process for a signature, assessing possible signature designs against the guidelines above. Due to their ubiquity, we chose a signature related to the Flow Duration Curve, selecting the FDC mid-section slope as a proposed signature to quantify catchment overall behavior and flashiness. We demonstrate how assessment against each guideline could be used to

Ideal Positions: 3D Sonography, Medical Visuality, Popular Culture.

PubMed

Seiber, Tim

2016-03-01

As digital technologies are integrated into medical environments, they continue to transform the experience of contemporary health care. Importantly, medicine is increasingly visual. In the history of sonography, visibility has played an important role in accessing fetal bodies for diagnostic and entertainment purposes. With the advent of three-dimensional (3D) rendering, sonography presents the fetus visually as already a child. The aesthetics of this process and the resulting imagery, made possible in digital networks, discloses important changes in the relationship between technology and biology, reproductive health and political debates, and biotechnology and culture.

Visualization and Image Analysis of Yeast Cells.

PubMed

Bagley, Steve

2016-01-01

When converting real-life data via visualization to numbers and then onto statistics the whole system needs to be considered so that conversion from the analogue to the digital is accurate and repeatable. Here we describe the points to consider when approaching yeast cell analysis visualization, processing, and analysis of a population by screening techniques.

Digital diagnosis of medical images

NASA Astrophysics Data System (ADS)

Heinonen, Tomi; Kuismin, Raimo; Jormalainen, Raimo; Dastidar, Prasun; Frey, Harry; Eskola, Hannu

2001-08-01

The popularity of digital imaging devices and PACS installations has increased during the last years. Still, images are analyzed and diagnosed using conventional techniques. Our research group begun to study the requirements for digital image diagnostic methods to be applied together with PACS systems. The research was focused on various image analysis procedures (e.g., segmentation, volumetry, 3D visualization, image fusion, anatomic atlas, etc.) that could be useful in medical diagnosis. We have developed Image Analysis software (www.medimag.net) to enable several image-processing applications in medical diagnosis, such as volumetry, multimodal visualization, and 3D visualizations. We have also developed a commercial scalable image archive system (ActaServer, supports DICOM) based on component technology (www.acta.fi), and several telemedicine applications. All the software and systems operate in NT environment and are in clinical use in several hospitals. The analysis software have been applied in clinical work and utilized in numerous patient cases (500 patients). This method has been used in the diagnosis, therapy and follow-up in various diseases of the central nervous system (CNS), respiratory system (RS) and human reproductive system (HRS). In many of these diseases e.g. Systemic Lupus Erythematosus (CNS), nasal airways diseases (RS) and ovarian tumors (HRS), these methods have been used for the first time in clinical work. According to our results, digital diagnosis improves diagnostic capabilities, and together with PACS installations it will become standard tool during the next decade by enabling more accurate diagnosis and patient follow-up.

Training system for digital mammographic diagnoses of breast cancer

NASA Astrophysics Data System (ADS)

Thomaz, R. L.; Nirschl Crozara, M. G.; Patrocinio, A. C.

2013-03-01

As the technology evolves, the analog mammography systems are being replaced by digital systems. The digital system uses video monitors as the display of mammographic images instead of the previously used screen-film and negatoscope for analog images. The change in the way of visualizing mammographic images may require a different approach for training the health care professionals in diagnosing the breast cancer with digital mammography. Thus, this paper presents a computational approach to train the health care professionals providing a smooth transition between analog and digital technology also training to use the advantages of digital image processing tools to diagnose the breast cancer. This computational approach consists of a software where is possible to open, process and diagnose a full mammogram case from a database, which has the digital images of each of the mammographic views. The software communicates with a gold standard digital mammogram cases database. This database contains the digital images in Tagged Image File Format (TIFF) and the respective diagnoses according to BI-RADSTM, these files are read by software and shown to the user as needed. There are also some digital image processing tools that can be used to provide better visualization of each single image. The software was built based on a minimalist and a user-friendly interface concept that might help in the smooth transition. It also has an interface for inputting diagnoses from the professional being trained, providing a result feedback. This system has been already completed, but hasn't been applied to any professional training yet.

[Visual perception and its disorders].

PubMed

Ruf-Bächtiger, L

1989-11-21

It's the brain and not the eye that decides what is perceived. In spite of this fact, quite a lot is known about the functioning of the eye and the first sections of the optic tract, but little about the actual process of perception. Examination of visual perception and its malfunctions relies therefore on certain hypotheses. Proceeding from the model of functional brain systems, variant functional domains of visual perception can be distinguished. Among the more important of these domains are: digit span, visual discrimination and figure-ground discrimination. Evaluation of these functional domains allows us to understand those children with disorders of visual perception better and to develop more effective treatment methods.

Hyperspectral signatures and WorldView-3 imagery of Indian River Lagoon and Banana River Estuarine water and bottom types

NASA Astrophysics Data System (ADS)

Bostater, Charles R.; Oney, Taylor S.; Rotkiske, Tyler; Aziz, Samin; Morrisette, Charles; Callahan, Kelby; Mcallister, Devin

2017-10-01

Hyperspectral signatures and imagery collected during the spring and summer of 2017 and 2016 are presented. Ground sampling distances (GSD) and pixel sizes were sampled from just over a meter to less than 4.0 mm. A pushbroom hyperspectral imager was used to calculate bidirectional reflectance factor (BRF) signatures. Hyperspectral signatures of different water types and bottom habitats such as submerged seagrasses, drift algae and algal bloom waters were scanned using a high spectral and digital resolution solid state spectrograph. WorldView-3 satellite imagery with minimal water wave sun glint effects was used to demonstrate the ability to detect bottom features using a derivative reflectance spectroscopy approach with the 1.3 m GSD multispectral satellite channels centered at the solar induced fluorescence band. The hyperspectral remote sensing data collected from the Banana River and Indian River Lagoon watersheds represents previously unknown signatures to be used in satellite and airborne remote sensing of water in turbid waters along the US Atlantic Ocean coastal region and the Florida littoral zone.

Producing Curious Affects: Visual Methodology as an Affecting and Conflictual Wunderkammer

ERIC Educational Resources Information Center

Staunaes, Dorthe; Kofoed, Jette

2015-01-01

Digital video cameras, smartphones, internet and iPads are increasingly used as visual research methods with the purpose of creating an affective corpus of data. Such visual methods are often combined with interviews or observations. Not only are visual methods part of the used research methods, the visual products are used as requisites in…

Visually enhanced CCTV digital surveillance utilizing Intranet and Internet.

PubMed

Ozaki, Nobuyuki

2002-07-01

This paper describes a solution for integrated plant supervision utilizing closed circuit television (CCTV) digital surveillance. Three basic requirements are first addressed as the platform of the system, with discussion on the suitable video compression. The system configuration is described in blocks. The system provides surveillance functionality: real-time monitoring, and process analysis functionality: a troubleshooting tool. This paper describes the formulation of practical performance design for determining various encoder parameters. It also introduces image processing techniques for enhancing the original CCTV digital image to lessen the burden on operators. Some screenshots are listed for the surveillance functionality. For the process analysis, an image searching filter supported by image processing techniques is explained with screenshots. Multimedia surveillance, which is the merger with process data surveillance, or the SCADA system, is also explained.

Digital Longitudinal Tomosynthesis

NASA Astrophysics Data System (ADS)

Rimkus, Daniel Steven

1985-12-01

The purpose of this dissertation was to investigate the clinical utility of digital longitudinal tomosynthesis in radiology. By acquiring a finite group of digital images during a longitudinal tomographic exposure, and processing these images, tomographic planes, other than the fulcrum plane, can be reconstructed. This process is now termed "tomosynthesis". A prototype system utilizing this technique was developed. Both phantom and patient studies were done with this system. The phantom studies were evaluated by subjective, visual criterion and by quantitative analysis of edge sharpness and noise in the reconstructions. Two groups of patients and one volunteer were studied. The first patient group consisted of 8 patients undergoing intravenous urography (IVU). These patients had digital tomography and film tomography of the abdomen. The second patient group consisted of 4 patients with lung cancer admitted to the hospital for laser resection of endobronchial tumor. These patients had mediastinal digital tomograms to evaluate the trachea and mainstem bronchi. The knee of one volunteer was imaged by film tomography and digital tomography. The results of the phantom studies showed that the digital reconstructions accurately produced images of the desired planes. The edge sharpness of the reconstructions approached that of the acquired images. Adequate reconstructions were achieved with as few as 5 images acquired during the exposure, with the quality of the reconstructions improving as the number of images acquired increased. The IVU patients' digital studies had less contrast and spatial resolution than the film tomograms. The single renal lesion visible on the film tomograms was also visible in the digital images. The digital mediastinal studies were felt by several radiologists to be superior to a standard chest xray in evaluating the airways. The digital images of the volunteer's knee showed many of the same anatomic features as the film tomogram, but the digital

Gestalt Perceptual Organization of Visual Stimuli Captures Attention Automatically: Electrophysiological Evidence

PubMed Central

Marini, Francesco; Marzi, Carlo A.

2016-01-01

The visual system leverages organizational regularities of perceptual elements to create meaningful representations of the world. One clear example of such function, which has been formalized in the Gestalt psychology principles, is the perceptual grouping of simple visual elements (e.g., lines and arcs) into unitary objects (e.g., forms and shapes). The present study sought to characterize automatic attentional capture and related cognitive processing of Gestalt-like visual stimuli at the psychophysiological level by using event-related potentials (ERPs). We measured ERPs during a simple visual reaction time task with bilateral presentations of physically matched elements with or without a Gestalt organization. Results showed that Gestalt (vs. non-Gestalt) stimuli are characterized by a larger N2pc together with enhanced ERP amplitudes of non-lateralized components (N1, N2, P3) starting around 150 ms post-stimulus onset. Thus, we conclude that Gestalt stimuli capture attention automatically and entail characteristic psychophysiological signatures at both early and late processing stages. Highlights We studied the neural signatures of the automatic processes of visual attention elicited by Gestalt stimuli. We found that a reliable early correlate of attentional capture turned out to be the N2pc component. Perceptual and cognitive processing of Gestalt stimuli is associated with larger N1, N2, and P3 PMID:27630555

Data Visualization and Animation Lab (DVAL) overview

NASA Technical Reports Server (NTRS)

Stacy, Kathy; Vonofenheim, Bill

1994-01-01

The general capabilities of the Langley Research Center Data Visualization and Animation Laboratory is described. These capabilities include digital image processing, 3-D interactive computer graphics, data visualization and analysis, video-rate acquisition and processing of video images, photo-realistic modeling and animation, video report generation, and color hardcopies. A specialized video image processing system is also discussed.

Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers.

PubMed

Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin

2017-01-01

Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation.

Impaired letter-string processing in developmental dyslexia: what visual-to-phonology code mapping disorder?

PubMed

Valdois, Sylviane; Lassus-Sangosse, Delphine; Lobier, Muriel

2012-05-01

Poor parallel letter-string processing in developmental dyslexia was taken as evidence of poor visual attention (VA) span, that is, a limitation of visual attentional resources that affects multi-character processing. However, the use of letter stimuli in oral report tasks was challenged on its capacity to highlight a VA span disorder. In particular, report of poor letter/digit-string processing but preserved symbol-string processing was viewed as evidence of poor visual-to-phonology code mapping, in line with the phonological theory of developmental dyslexia. We assessed here the visual-to-phonological-code mapping disorder hypothesis. In Experiment 1, letter-string, digit-string and colour-string processing was assessed to disentangle a phonological versus visual familiarity account of the letter/digit versus symbol dissociation. Against a visual-to-phonological-code mapping disorder but in support of a familiarity account, results showed poor letter/digit-string processing but preserved colour-string processing in dyslexic children. In Experiment 2, two tasks of letter-string report were used, one of which was performed simultaneously to a high-taxing phonological task. Results show that dyslexic children are similarly impaired in letter-string report whether a concurrent phonological task is simultaneously performed or not. Taken together, these results provide strong evidence against a phonological account of poor letter-string processing in developmental dyslexia. Copyright © 2012 John Wiley & Sons, Ltd.

Quantitative comparison and reproducibility of pathologist scoring and digital image analysis of estrogen receptor β2 immunohistochemistry in prostate cancer.

PubMed

Rizzardi, Anthony E; Zhang, Xiaotun; Vogel, Rachel Isaksson; Kolb, Suzanne; Geybels, Milan S; Leung, Yuet-Kin; Henriksen, Jonathan C; Ho, Shuk-Mei; Kwak, Julianna; Stanford, Janet L; Schmechel, Stephen C

2016-07-11

Digital image analysis offers advantages over traditional pathologist visual scoring of immunohistochemistry, although few studies examining the correlation and reproducibility of these methods have been performed in prostate cancer. We evaluated the correlation between digital image analysis (continuous variable data) and pathologist visual scoring (quasi-continuous variable data), reproducibility of each method, and association of digital image analysis methods with outcomes using prostate cancer tissue microarrays (TMAs) stained for estrogen receptor-β2 (ERβ2). Prostate cancer TMAs were digitized and evaluated by pathologist visual scoring versus digital image analysis for ERβ2 staining within tumor epithelium. Two independent analysis runs were performed to evaluate reproducibility. Image analysis data were evaluated for associations with recurrence-free survival and disease specific survival following radical prostatectomy. We observed weak/moderate Spearman correlation between digital image analysis and pathologist visual scores of tumor nuclei (Analysis Run A: 0.42, Analysis Run B: 0.41), and moderate/strong correlation between digital image analysis and pathologist visual scores of tumor cytoplasm (Analysis Run A: 0.70, Analysis Run B: 0.69). For the reproducibility analysis, there was high Spearman correlation between pathologist visual scores generated for individual TMA spots across Analysis Runs A and B (Nuclei: 0.84, Cytoplasm: 0.83), and very high correlation between digital image analysis for individual TMA spots across Analysis Runs A and B (Nuclei: 0.99, Cytoplasm: 0.99). Further, ERβ2 staining was significantly associated with increased risk of prostate cancer-specific mortality (PCSM) when quantified by cytoplasmic digital image analysis (HR 2.16, 95 % CI 1.02-4.57, p = 0.045), nuclear image analysis (HR 2.67, 95 % CI 1.20-5.96, p = 0.016), and total malignant epithelial area analysis (HR 5.10, 95 % CI 1.70-15.34, p = 0

Multicomponent analysis of a digital Trail Making Test.

PubMed

Fellows, Robert P; Dahmen, Jessamyn; Cook, Diane; Schmitter-Edgecombe, Maureen

2017-01-01

The purpose of the current study was to use a newly developed digital tablet-based variant of the TMT to isolate component cognitive processes underlying TMT performance. Similar to the paper-based trail making test, this digital variant consists of two conditions, Part A and Part B. However, this digital version automatically collects additional data to create component subtest scores to isolate cognitive abilities. Specifically, in addition to the total time to completion and number of errors, the digital Trail Making Test (dTMT) records several unique components including the number of pauses, pause duration, lifts, lift duration, time inside each circle, and time between circles. Participants were community-dwelling older adults who completed a neuropsychological evaluation including measures of processing speed, inhibitory control, visual working memory/sequencing, and set-switching. The abilities underlying TMT performance were assessed through regression analyses of component scores from the dTMT with traditional neuropsychological measures. Results revealed significant correlations between paper and digital variants of Part A (r s  = .541, p < .001) and paper and digital versions of Part B (r s  = .799, p < .001). Regression analyses with traditional neuropsychological measures revealed that Part A components were best predicted by speeded processing, while inhibitory control and visual/spatial sequencing were predictors of specific components of Part B. Exploratory analyses revealed that specific dTMT-B components were associated with a performance-based medication management task. Taken together, these results elucidate specific cognitive abilities underlying TMT performance, as well as the utility of isolating digital components.

Open data and digital morphology

PubMed Central

Davies, Thomas G.; Cunningham, John A.; Asher, Robert J.; Bates, Karl T.; Bengtson, Stefan; Benson, Roger B. J.; Boyer, Doug M.; Braga, José; Dong, Xi-Ping; Evans, Alistair R.; Friedman, Matt; Garwood, Russell J.; Goswami, Anjali; Hutchinson, John R.; Jeffery, Nathan S.; Lebrun, Renaud; Martínez-Pérez, Carlos; O'Higgins, Paul M.; Orliac, Maëva; Rowe, Timothy B.; Sánchez-Villagra, Marcelo R.; Shubin, Neil H.; Starck, J. Matthias; Stringer, Chris; Summers, Adam P.; Sutton, Mark D.; Walsh, Stig A.; Weisbecker, Vera; Witmer, Lawrence M.; Wroe, Stephen; Yin, Zongjun

2017-01-01

Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies that use, and in some cases are wholly reliant on, digital morphology. Here, we propose a set of recommendations for minimum standards and additional best practice for three-dimensional digital data publication, and review the issues around data storage, management and accessibility. PMID:28404779

Open data and digital morphology.

PubMed

Davies, Thomas G; Rahman, Imran A; Lautenschlager, Stephan; Cunningham, John A; Asher, Robert J; Barrett, Paul M; Bates, Karl T; Bengtson, Stefan; Benson, Roger B J; Boyer, Doug M; Braga, José; Bright, Jen A; Claessens, Leon P A M; Cox, Philip G; Dong, Xi-Ping; Evans, Alistair R; Falkingham, Peter L; Friedman, Matt; Garwood, Russell J; Goswami, Anjali; Hutchinson, John R; Jeffery, Nathan S; Johanson, Zerina; Lebrun, Renaud; Martínez-Pérez, Carlos; Marugán-Lobón, Jesús; O'Higgins, Paul M; Metscher, Brian; Orliac, Maëva; Rowe, Timothy B; Rücklin, Martin; Sánchez-Villagra, Marcelo R; Shubin, Neil H; Smith, Selena Y; Starck, J Matthias; Stringer, Chris; Summers, Adam P; Sutton, Mark D; Walsh, Stig A; Weisbecker, Vera; Witmer, Lawrence M; Wroe, Stephen; Yin, Zongjun; Rayfield, Emily J; Donoghue, Philip C J

2017-04-12

Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies that use, and in some cases are wholly reliant on, digital morphology. Here, we propose a set of recommendations for minimum standards and additional best practice for three-dimensional digital data publication, and review the issues around data storage, management and accessibility. © 2017 The Authors.

Ultra-Rapid serial visual presentation reveals dynamics of feedforward and feedback processes in the ventral visual pathway.

PubMed

Mohsenzadeh, Yalda; Qin, Sheng; Cichy, Radoslaw M; Pantazis, Dimitrios

2018-06-21

Human visual recognition activates a dense network of overlapping feedforward and recurrent neuronal processes, making it hard to disentangle processing in the feedforward from the feedback direction. Here, we used ultra-rapid serial visual presentation to suppress sustained activity that blurs the boundaries of processing steps, enabling us to resolve two distinct stages of processing with MEG multivariate pattern classification. The first processing stage was the rapid activation cascade of the bottom-up sweep, which terminated early as visual stimuli were presented at progressively faster rates. The second stage was the emergence of categorical information with peak latency that shifted later in time with progressively faster stimulus presentations, indexing time-consuming recurrent processing. Using MEG-fMRI fusion with representational similarity, we localized recurrent signals in early visual cortex. Together, our findings segregated an initial bottom-up sweep from subsequent feedback processing, and revealed the neural signature of increased recurrent processing demands for challenging viewing conditions. © 2018, Mohsenzadeh et al.

Uncertainty in hydrological signatures

NASA Astrophysics Data System (ADS)

McMillan, Hilary; Westerberg, Ida

2015-04-01

Information that summarises the hydrological behaviour or flow regime of a catchment is essential for comparing responses of different catchments to understand catchment organisation and similarity, and for many other modelling and water-management applications. Such information types derived as an index value from observed data are known as hydrological signatures, and can include descriptors of high flows (e.g. mean annual flood), low flows (e.g. mean annual low flow, recession shape), the flow variability, flow duration curve, and runoff ratio. Because the hydrological signatures are calculated from observed data such as rainfall and flow records, they are affected by uncertainty in those data. Subjective choices in the method used to calculate the signatures create a further source of uncertainty. Uncertainties in the signatures may affect our ability to compare different locations, to detect changes, or to compare future water resource management scenarios. The aim of this study was to contribute to the hydrological community's awareness and knowledge of data uncertainty in hydrological signatures, including typical sources, magnitude and methods for its assessment. We proposed a generally applicable method to calculate these uncertainties based on Monte Carlo sampling and demonstrated it for a variety of commonly used signatures. The study was made for two data rich catchments, the 50 km2 Mahurangi catchment in New Zealand and the 135 km2 Brue catchment in the UK. For rainfall data the uncertainty sources included point measurement uncertainty, the number of gauges used in calculation of the catchment spatial average, and uncertainties relating to lack of quality control. For flow data the uncertainty sources included uncertainties in stage/discharge measurement and in the approximation of the true stage-discharge relation by a rating curve. The resulting uncertainties were compared across the different signatures and catchments, to quantify uncertainty

Enhanced alpha-oscillations in visual cortex during anticipation of self-generated visual stimulation.

PubMed

Stenner, Max-Philipp; Bauer, Markus; Haggard, Patrick; Heinze, Hans-Jochen; Dolan, Ray

2014-11-01

The perceived intensity of sensory stimuli is reduced when these stimuli are caused by the observer's actions. This phenomenon is traditionally explained by forward models of sensory action-outcome, which arise from motor processing. Although these forward models critically predict anticipatory modulation of sensory neural processing, neurophysiological evidence for anticipatory modulation is sparse and has not been linked to perceptual data showing sensory attenuation. By combining a psychophysical task involving contrast discrimination with source-level time-frequency analysis of MEG data, we demonstrate that the amplitude of alpha-oscillations in visual cortex is enhanced before the onset of a visual stimulus when the identity and onset of the stimulus are controlled by participants' motor actions. Critically, this prestimulus enhancement of alpha-amplitude is paralleled by psychophysical judgments of a reduced contrast for this stimulus. We suggest that alpha-oscillations in visual cortex preceding self-generated visual stimulation are a likely neurophysiological signature of motor-induced sensory anticipation and mediate sensory attenuation. We discuss our results in relation to proposals that attribute generic inhibitory functions to alpha-oscillations in prioritizing and gating sensory information via top-down control.

Signatures of local adaptation along environmental gradients in a range-expanding damselfly (Ischnura elegans).

PubMed

Dudaniec, Rachael Y; Yong, Chuan Ji; Lancaster, Lesley T; Svensson, Erik I; Hansson, Bengt

2018-06-01

Insect distributions are shifting rapidly in response to climate change and are undergoing rapid evolutionary change. We investigate the molecular signatures underlying local adaptation in the range-expanding damselfly, Ischnura elegans. Using a landscape genomic approach combined with generalized dissimilarity modelling (GDM), we detect selection signatures on loci via allelic frequency change along environmental gradients. We analyse 13,612 single nucleotide polymorphisms (SNPs), derived from restriction site-associated DNA sequencing (RADseq), in 426 individuals from 25 sites spanning the I. elegans distribution in Sweden, including its expanding northern range edge. Environmental association analysis (EAA) and the magnitude of allele frequency change along the range expansion gradient revealed significant signatures of selection in relation to high maximum summer temperature, high mean annual precipitation and low wind speeds at the range edge. SNP annotations with significant signatures of selection revealed gene functions associated with ongoing range expansion, including heat shock proteins (HSP40 and HSP70), ion transport (V-ATPase) and visual processes (long-wavelength-sensitive opsin), which have implications for thermal stress response, salinity tolerance and mate discrimination, respectively. We also identified environmental thresholds where climate-mediated selection is likely to be strong, and indicate that I. elegans is rapidly adapting to the climatic environment during its ongoing range expansion. Our findings empirically validate an integrative approach for detecting spatially explicit signatures of local adaptation along environmental gradients. © 2018 John Wiley & Sons Ltd.

Visual Form Perception Can Be a Cognitive Correlate of Lower Level Math Categories for Teenagers

PubMed Central

Cui, Jiaxin; Zhang, Yiyun; Cheng, Dazhi; Li, Dawei; Zhou, Xinlin

2017-01-01

Numerous studies have assessed the cognitive correlates of performance in mathematics, but little research has been conducted to systematically examine the relations between visual perception as the starting point of visuospatial processing and typical mathematical performance. In the current study, we recruited 223 seventh graders to perform a visual form perception task (figure matching), numerosity comparison, digit comparison, exact computation, approximate computation, and curriculum-based mathematical achievement tests. Results showed that, after controlling for gender, age, and five general cognitive processes (choice reaction time, visual tracing, mental rotation, spatial working memory, and non-verbal matrices reasoning), visual form perception had unique contributions to numerosity comparison, digit comparison, and exact computation, but had no significant relation with approximate computation or curriculum-based mathematical achievement. These results suggest that visual form perception is an important independent cognitive correlate of lower level math categories, including the approximate number system, digit comparison, and exact computation. PMID:28824513

Information, entropy, and fidelity in visual communication

NASA Astrophysics Data System (ADS)

Huck, Friedrich O.; Fales, Carl L.; Alter-Gartenberg, Rachel; Rahman, Zia-ur

1992-10-01

This paper presents an assessment of visual communication that integrates the critical limiting factors of image gathering an display with the digital processing that is used to code and restore images. The approach focuses on two mathematical criteria, information and fidelity, and on their relationships to the entropy of the encoded data and to the visual quality of the restored image.

Information, entropy and fidelity in visual communication

NASA Technical Reports Server (NTRS)

Huck, Friedrich O.; Fales, Carl L.; Alter-Gartenberg, Rachel; Rahman, Zia-Ur

1992-01-01

This paper presents an assessment of visual communication that integrates the critical limiting factors of image gathering and display with the digital processing that is used to code and restore images. The approach focuses on two mathematical criteria, information and fidelity, and on their relationships to the entropy of the encoded data and to the visual quality of the restored image.

Use of digital photography for power plant retrofits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamba, J.J.

1995-09-01

One of the latest advancements in electronic tools for reducing engineering and drafting effort is the use of digital photography (DP) for retrofit and betterment projects at fossil and nuclear power plants. Sargent and Lundy (S and L) has effectively used digital photography for condition assessments, minor backfit repairs, thermo-lag fire wrap assessments and repairs, and other applications. Digital photography offers several benefits on these types of projects including eliminating the need for official repair drawings and providing station maintenance with a true 3-D visualization of the repair.

Display Device Color Management and Visual Surveillance of Vehicles

ERIC Educational Resources Information Center

Srivastava, Satyam

2011-01-01

Digital imaging has seen an enormous growth in the last decade. Today users have numerous choices in creating, accessing, and viewing digital image/video content. Color management is important to ensure consistent visual experience across imaging systems. This is typically achieved using color profiles. In this thesis we identify the limitations…

Construction of a VISUAL (VIdeo-SUpported Active Learning) Resource.

ERIC Educational Resources Information Center

Nicolson, Roderick I.; And Others

1994-01-01

Discussion of interactive video for educational purposes focuses on the development of a video-supported active learning (VISUAL) resource on voice disorders that used digitized video and an Apple Macintosh computer. User evaluations are reported, and potential applications for VISUAL resources are suggested. (Contains five references.) (LRW)

Visual Literacy for Libraries: A Practical, Standards­-Based Guide

ERIC Educational Resources Information Center

Brown, Nicole E.; Bussert, Kaila; Hattwig, Denise; Medaille, Ann

2016-01-01

The importance of images and visual media in today's culture is changing what it means to be literate in the 21st century. Digital technologies have made it possible for almost anyone to create and share visual media. Yet the pervasiveness of images and visual media does not necessarily mean that individuals are able to critically view, use, and…

Signature extension studies

NASA Technical Reports Server (NTRS)

Vincent, R. K.; Thomas, G. S.; Nalepka, R. F.

1974-01-01

The importance of specific spectral regions to signature extension is explored. In the recent past, the signature extension task was focused on the development of new techniques. Tested techniques are now used to investigate this spectral aspect of the large area survey. Sets of channels were sought which, for a given technique, were the least affected by several sources of variation over four data sets and yet provided good object class separation on each individual data set. Using sets of channels determined as part of this study, signature extension was accomplished between data sets collected over a six-day period and over a range of about 400 kilometers.

Intuitive color-based visualization of multimedia content as large graphs

NASA Astrophysics Data System (ADS)

Delest, Maylis; Don, Anthony; Benois-Pineau, Jenny

2004-06-01

Data visualization techniques are penetrating in various technological areas. In the field of multimedia such as information search and retrieval in multimedia archives, or digital media production and post-production, data visualization methodologies based on large graphs give an exciting alternative to conventional storyboard visualization. In this paper we develop a new approach to visualization of multimedia (video) documents based both on large graph clustering and preliminary video segmenting and indexing.

Visual pattern image sequence coding

NASA Technical Reports Server (NTRS)

Silsbee, Peter; Bovik, Alan C.; Chen, Dapang

1990-01-01

The visual pattern image coding (VPIC) configurable digital image-coding process is capable of coding with visual fidelity comparable to the best available techniques, at compressions which (at 30-40:1) exceed all other technologies. These capabilities are associated with unprecedented coding efficiencies; coding and decoding operations are entirely linear with respect to image size and entail a complexity that is 1-2 orders of magnitude faster than any previous high-compression technique. The visual pattern image sequence coding to which attention is presently given exploits all the advantages of the static VPIC in the reduction of information from an additional, temporal dimension, to achieve unprecedented image sequence coding performance.

Visual Simulation The Old Way

NASA Astrophysics Data System (ADS)

Gomes, Gary G.

1986-05-01

A cost effective and supportable color visual system has been developed to provide the necessary visual cues to United States Air Force B-52 bomber pilots training to become proficient at the task of inflight refueling. This camera model visual system approach is not suitable for all simulation applications, but provides a cost effective alternative to digital image generation systems when high fidelity of a single movable object is required. The system consists of a three axis gimballed KC-l35 tanker model, a range carriage mounted color augmented monochrome television camera, interface electronics, a color light valve projector and an infinity optics display system.

Visual working memory simultaneously guides facilitation and inhibition during visual search.

PubMed

Dube, Blaire; Basciano, April; Emrich, Stephen M; Al-Aidroos, Naseem

2016-07-01

During visual search, visual working memory (VWM) supports the guidance of attention in two ways: It stores the identity of the search target, facilitating the selection of matching stimuli in the search array, and it maintains a record of the distractors processed during search so that they can be inhibited. In two experiments, we investigated whether the full contents of VWM can be used to support both of these abilities simultaneously. In Experiment 1, participants completed a preview search task in which (a) a subset of search distractors appeared before the remainder of the search items, affording participants the opportunity to inhibit them, and (b) the search target varied from trial to trial, requiring the search target template to be maintained in VWM. We observed the established signature of VWM-based inhibition-reduced ability to ignore previewed distractors when the number of distractors exceeds VWM's capacity-suggesting that VWM can serve this role while also representing the target template. In Experiment 2, we replicated Experiment 1, but added to the search displays a singleton distractor that sometimes matched the color (a task-irrelevant feature) of the search target, to evaluate capture. We again observed the signature of VWM-based preview inhibition along with attentional capture by (and, thus, facilitation of) singletons matching the target template. These findings indicate that more than one VWM representation can bias attention at a time, and that these representations can separately affect selection through either facilitation or inhibition, placing constraints on existing models of the VWM-based guidance of attention.

Does the choice of display system influence perception and visibility of clinically relevant features in digital pathology images?

NASA Astrophysics Data System (ADS)

Kimpe, Tom; Rostang, Johan; Avanaki, Ali; Espig, Kathryn; Xthona, Albert; Cocuranu, Ioan; Parwani, Anil V.; Pantanowitz, Liron

2014-03-01

Digital pathology systems typically consist of a slide scanner, processing software, visualization software, and finally a workstation with display for visualization of the digital slide images. This paper studies whether digital pathology images can look different when presenting them on different display systems, and whether these visual differences can result in different perceived contrast of clinically relevant features. By analyzing a set of four digital pathology images of different subspecialties on three different display systems, it was concluded that pathology images look different when visualized on different display systems. The importance of these visual differences is elucidated when they are located in areas of the digital slide that contain clinically relevant features. Based on a calculation of dE2000 differences between background and clinically relevant features, it was clear that perceived contrast of clinically relevant features is influenced by the choice of display system. Furthermore, it seems that the specific calibration target chosen for the display system has an important effect on the perceived contrast of clinically relevant features. Preliminary results suggest that calibrating to DICOM GSDF calibration performed slightly worse than sRGB, while a new experimental calibration target CSDF performed better than both DICOM GSDF and sRGB. This result is promising as it suggests that further research work could lead to better definition of an optimized calibration target for digital pathology images resulting in a positive effect on clinical performance.

Low-cost computer classification of land cover in the Portland area, Oregon, by signature extension techniques

USGS Publications Warehouse

Gaydos, Leonard

1978-01-01

The cost of classifying 5,607 square kilometers (2,165 sq. mi.) in the Portland area was less than 8 cents per square kilometer ($0.0788, or $0.2041 per square mile). Besides saving in costs, this and other signature extension techniques may be useful in completing land use and land cover mapping in other large areas where multispectral and multitemporal Landsat data are available in digital form but other source materials are generally lacking.

Get a Grip: Substrate Orientation and Digital Grasping Pressures in Strepsirrhines.

PubMed

Congdon, Kimberly A; Ravosa, Matthew J

2016-01-01

Skeletal functional morphology in primates underlies many fossil interpretations. Understanding the functional correlates of arboreal grasping is central to identifying locomotor signatures in extinct primates. We tested 3 predictions linking substrate orientation and digital grasping pressures: (1) below-branch pressures are greater than above-branch and vertical-branch pressures; (2) there is no difference in pressure exerted across digits within autopods at any substrate orientation, and (3) there is no difference in pressure exerted between homologous digits across autopods at any substrate orientation. Adult males and females from 3 strepsirrhine species crossed an artificial arboreal substrate oriented for above-, below- and vertical-branch locomotion. We compared digital pressures within and across behaviors via ANOVA and Tukey's Honest Significant Difference test. Results show limited support for all predictions: below-branch pressures exceeded vertical-branch pressures and above-branch pressures for some digits and species (prediction 1), lateral digits often exerted greater pressures than medial digits (prediction 2), and pedal digits occasionally exerted greater pressures than manual digits during above-branch and vertical orientations but less often for below-branch locomotion (prediction 3). We observed functional variability across autopods, substrate and species that could underlie morphological variation within and across primates. Future work should consider the complexity of arboreality when inferring locomotor modes in fossils. © 2016 S. Karger AG, Basel.

Lesson 6: Signature Validation

EPA Pesticide Factsheets

Checklist items 13 through 17 are grouped under the Signature Validation Process, and represent CROMERR requirements that the system must satisfy as part of ensuring that electronic signatures it receives are valid.

21 CFR 11.50 - Signature manifestations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Signature manifestations. 11.50 Section 11.50 Food... RECORDS; ELECTRONIC SIGNATURES Electronic Records § 11.50 Signature manifestations. (a) Signed electronic...: (1) The printed name of the signer; (2) The date and time when the signature was executed; and (3...

The CommonGround Visual Paradigm for Biosurveillance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Livnat, Yarden; Jurrus, Elizabeth R.; Gundlapalli, Adi V.

2013-06-14

Biosurveillance is a critical area in the intelligence community for real-time detection of disease outbreaks. Identifying epidemics enables analysts to detect and monitor disease outbreaks that might be spread from natural causes or from possible biological warfare attacks. Containing these events and disseminating alerts requires the ability to rapidly find, classify and track harmful biological signatures. In this paper, we describe a novel visual paradigm to conduct biosurveillance using an Infectious Disease Weather Map. Our system provides a visual common ground in which users can view, explore and discover emerging concepts and correlations such as symptoms, syndromes, pathogens, and geographicmore » locations.« less

Visual business ecosystem intelligence: lessons from the field.

PubMed

Basole, Rahul C

2014-01-01

Macroscopic insight into business ecosystems is becoming increasingly important. With the emergence of new digital business data, opportunities exist to develop rich, interactive visual-analytics tools. Georgia Institute of Technology researchers have been developing and implementing visual business ecosystem intelligence tools in corporate settings. This article discusses the challenges they faced, the lessons learned, and opportunities for future research.

Quality of signatures. [spectral signatures of winter wheat grown in Texas

NASA Technical Reports Server (NTRS)

Kan, E. P. F.

1974-01-01

Three conclusions are drawn on the usability, inherent variations, and noise aspects of the spectral signatures processed from data collected by the Field Signature Acquisition System (FSAS). Conclusions are based on the spectral data collected from winter wheat of the 1972/73 season, grown at Texas A and M University, College Station, Texas.

Accessing and Visualizing scientific spatiotemporal data

NASA Technical Reports Server (NTRS)

Katz, Daniel S.; Bergou, Attila; Berriman, Bruce G.; Block, Gary L.; Collier, Jim; Curkendall, David W.; Good, John; Husman, Laura; Jacob, Joseph C.; Laity, Anastasia;

Examining live cell cultures during apoptosis by digital holographic phase imaging and Raman spectroscopy

NASA Astrophysics Data System (ADS)

Khmaladze, Alexander

2017-11-01

Cellular apoptosis is a unique, organized series of events, leading to programmed cell death. In this work, we present a combined digital holography/Raman spectroscopy technique to study live cell cultures during apoptosis. Digital holographic microscopy measurements of live cell cultures yield information about cell shape and volume, changes to which are indicative of alterations in cell cycle and initiation of cell death mechanisms. Raman spectroscopic measurements provide complementary information about cells, such as protein, lipid and nucleic acid content, and the spectral signatures associated with structural changes in molecules. Our work indicates that the chemical changes in proteins, which were detected by Raman measurements, preceded morphological changes, which were seen with digital holographic microscopy.

Heart energy signature spectrogram for cardiovascular diagnosis

PubMed Central

Kudriavtsev, Vladimir; Polyshchuk, Vladimir; Roy, Douglas L

2007-01-01

A new method and application is proposed to characterize intensity and pitch of human heart sounds and murmurs. Using recorded heart sounds from the library of one of the authors, a visual map of heart sound energy was established. Both normal and abnormal heart sound recordings were studied. Representation is based on Wigner-Ville joint time-frequency transformations. The proposed methodology separates acoustic contributions of cardiac events simultaneously in pitch, time and energy. The resolution accuracy is superior to any other existing spectrogram method. The characteristic energy signature of the innocent heart murmur in a child with the S3 sound is presented. It allows clear detection of S1, S2 and S3 sounds, S2 split, systolic murmur, and intensity of these components. The original signal, heart sound power change with time, time-averaged frequency, energy density spectra and instantaneous variations of power and frequency/pitch with time, are presented. These data allow full quantitative characterization of heart sounds and murmurs. High accuracy in both time and pitch resolution is demonstrated. Resulting visual images have self-referencing quality, whereby individual features and their changes become immediately obvious. PMID:17480232

7 CFR 97.155 - Signatures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Signatures. 97.155 Section 97.155 Agriculture... PLANT VARIETY AND PROTECTION Attorneys and Agents § 97.155 Signatures. Every document filed by an attorney or agent representing an applicant or party to a proceeding in the Office shall bear the signature...

21 CFR 11.70 - Signature/record linking.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Signature/record linking. 11.70 Section 11.70 Food... RECORDS; ELECTRONIC SIGNATURES Electronic Records § 11.70 Signature/record linking. Electronic signatures and handwritten signatures executed to electronic records shall be linked to their respective...

Beyond Words: An Enquiry into Children's Home Visual Communication Practices

ERIC Educational Resources Information Center

Yamada-Rice, Dylan

2010-01-01

This research focuses on young children's experiences of the visual mode embedded in new multimodal literacy practices. An enquiry was undertaken into the role of visual and digital images in a group of 11 four-year-olds' out-of-school lives. The children photographed their use of a range of primarily visual-based media at home, to produce a book…

Anatomical constraints on attention: Hemifield independence is a signature of multifocal spatial selection

PubMed Central

Alvarez, George A; Gill, Jonathan; Cavanagh, Patrick

2012-01-01

Previous studies have shown independent attentional selection of targets in the left and right visual hemifields during attentional tracking (Alvarez & Cavanagh, 2005) but not during a visual search (Luck, Hillyard, Mangun, & Gazzaniga, 1989). Here we tested whether multifocal spatial attention is the critical process that operates independently in the two hemifields. It is explicitly required in tracking (attend to a subset of object locations, suppress the others) but not in the standard visual search task (where all items are potential targets). We used a modified visual search task in which observers searched for a target within a subset of display items, where the subset was selected based on location (Experiments 1 and 3A) or based on a salient feature difference (Experiments 2 and 3B). The results show hemifield independence in this subset visual search task with location-based selection but not with feature-based selection; this effect cannot be explained by general difficulty (Experiment 4). Combined, these findings suggest that hemifield independence is a signature of multifocal spatial attention and highlight the need for cognitive and neural theories of attention to account for anatomical constraints on selection mechanisms. PMID:22637710

A digital ISO expansion technique for digital cameras

NASA Astrophysics Data System (ADS)

Yoo, Youngjin; Lee, Kangeui; Choe, Wonhee; Park, SungChan; Lee, Seong-Deok; Kim, Chang-Yong

2010-01-01

Market's demands of digital cameras for higher sensitivity capability under low-light conditions are remarkably increasing nowadays. The digital camera market is now a tough race for providing higher ISO capability. In this paper, we explore an approach for increasing maximum ISO capability of digital cameras without changing any structure of an image sensor or CFA. Our method is directly applied to the raw Bayer pattern CFA image to avoid non-linearity characteristics and noise amplification which are usually deteriorated after ISP (Image Signal Processor) of digital cameras. The proposed method fuses multiple short exposed images which are noisy, but less blurred. Our approach is designed to avoid the ghost artifact caused by hand-shaking and object motion. In order to achieve a desired ISO image quality, both low frequency chromatic noise and fine-grain noise that usually appear in high ISO images are removed and then we modify the different layers which are created by a two-scale non-linear decomposition of an image. Once our approach is performed on an input Bayer pattern CFA image, the resultant Bayer image is further processed by ISP to obtain a fully processed RGB image. The performance of our proposed approach is evaluated by comparing SNR (Signal to Noise Ratio), MTF50 (Modulation Transfer Function), color error ~E*ab and visual quality with reference images whose exposure times are properly extended into a variety of target sensitivity.

On the assessment of visual communication by information theory

NASA Technical Reports Server (NTRS)

Huck, Friedrich O.; Fales, Carl L.

1993-01-01

This assessment of visual communication integrates the optical design of the image-gathering device with the digital processing for image coding and restoration. Results show that informationally optimized image gathering ordinarily can be relied upon to maximize the information efficiency of decorrelated data and the visual quality of optimally restored images.

Novel signatures of cancer-associated fibroblasts.

PubMed

Bozóky, Benedek; Savchenko, Andrii; Csermely, Péter; Korcsmáros, Tamás; Dúl, Zoltán; Pontén, Fredrik; Székely, László; Klein, George

2013-07-15

Increasing evidence indicates the importance of the tumor microenvironment, in particular cancer-associated fibroblasts, in cancer development and progression. In our study, we developed a novel, visually based method to identify new immunohistochemical signatures of these fibroblasts. The method employed a protein list based on 759 protein products of genes identified by RNA profiling from our previous study, comparing fibroblasts with differential growth-modulating effect on human cancers cells, and their first neighbors in the human protein interactome. These 2,654 proteins were analyzed in the Human Protein Atlas online database by comparing their immunohistochemical expression patterns in normal versus tumor-associated fibroblasts. Twelve new proteins differentially expressed in cancer-associated fibroblasts were identified (DLG1, BHLHE40, ROCK2, RAB31, AZI2, PKM2, ARHGAP31, ARHGAP26, ITCH, EGLN1, RNF19A and PLOD2), four of them can be connected to the Rho kinase signaling pathway. They were further analyzed in several additional tumor stromata and revealed that the majority showed congruence among the different tumors. Many of them were also positive in normal myofibroblast-like cells. The new signatures can be useful in immunohistochemical analysis of different tumor stromata and may also give us an insight into the pathways activated in them in their true in vivo context. The method itself could be used for other similar analysis to identify proteins expressed in other cell types in tumors and their surrounding microenvironment. Copyright © 2013 UICC.

17 CFR 12.12 - Signature.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Signature. 12.12 Section 12.12... General Information and Preliminary Consideration of Pleadings § 12.12 Signature. (a) By whom. All... document on behalf of another person. (b) Effect. The signature on any document of any person acting either...

Visualizing curved spacetime

NASA Astrophysics Data System (ADS)

Jonsson, Rickard M.

2005-03-01

I present a way to visualize the concept of curved spacetime. The result is a curved surface with local coordinate systems (Minkowski systems) living on it, giving the local directions of space and time. Relative to these systems, special relativity holds. The method can be used to visualize gravitational time dilation, the horizon of black holes, and cosmological models. The idea underlying the illustrations is first to specify a field of timelike four-velocities uμ. Then, at every point, one performs a coordinate transformation to a local Minkowski system comoving with the given four-velocity. In the local system, the sign of the spatial part of the metric is flipped to create a new metric of Euclidean signature. The new positive definite metric, called the absolute metric, can be covariantly related to the original Lorentzian metric. For the special case of a two-dimensional original metric, the absolute metric may be embedded in three-dimensional Euclidean space as a curved surface.

A framework for interactive visualization of digital medical images.

PubMed

Koehring, Andrew; Foo, Jung Leng; Miyano, Go; Lobe, Thom; Winer, Eliot

2008-10-01

The visualization of medical images obtained from scanning techniques such as computed tomography and magnetic resonance imaging is a well-researched field. However, advanced tools and methods to manipulate these data for surgical planning and other tasks have not seen widespread use among medical professionals. Radiologists have begun using more advanced visualization packages on desktop computer systems, but most physicians continue to work with basic two-dimensional grayscale images or not work directly with the data at all. In addition, new display technologies that are in use in other fields have yet to be fully applied in medicine. It is our estimation that usability is the key aspect in keeping this new technology from being more widely used by the medical community at large. Therefore, we have a software and hardware framework that not only make use of advanced visualization techniques, but also feature powerful, yet simple-to-use, interfaces. A virtual reality system was created to display volume-rendered medical models in three dimensions. It was designed to run in many configurations, from a large cluster of machines powering a multiwalled display down to a single desktop computer. An augmented reality system was also created for, literally, hands-on interaction when viewing models of medical data. Last, a desktop application was designed to provide a simple visualization tool, which can be run on nearly any computer at a user's disposal. This research is directed toward improving the capabilities of medical professionals in the tasks of preoperative planning, surgical training, diagnostic assistance, and patient education.

Fine-grained temporal coding of visually-similar categories in the ventral visual pathway and prefrontal cortex

PubMed Central

Xu, Yang; D'Lauro, Christopher; Pyles, John A.; Kass, Robert E.; Tarr, Michael J.

2013-01-01

Humans are remarkably proficient at categorizing visually-similar objects. To better understand the cortical basis of this categorization process, we used magnetoencephalography (MEG) to record neural activity while participants learned–with feedback–to discriminate two highly-similar, novel visual categories. We hypothesized that although prefrontal regions would mediate early category learning, this role would diminish with increasing category familiarity and that regions within the ventral visual pathway would come to play a more prominent role in encoding category-relevant information as learning progressed. Early in learning we observed some degree of categorical discriminability and predictability in both prefrontal cortex and the ventral visual pathway. Predictability improved significantly above chance in the ventral visual pathway over the course of learning with the left inferior temporal and fusiform gyri showing the greatest improvement in predictability between 150 and 250 ms (M200) during category learning. In contrast, there was no comparable increase in discriminability in prefrontal cortex with the only significant post-learning effect being a decrease in predictability in the inferior frontal gyrus between 250 and 350 ms (M300). Thus, the ventral visual pathway appears to encode learned visual categories over the long term. At the same time these results add to our understanding of the cortical origins of previously reported signature temporal components associated with perceptual learning. PMID:24146656

Spectral features based tea garden extraction from digital orthophoto maps

NASA Astrophysics Data System (ADS)

Jamil, Akhtar; Bayram, Bulent; Kucuk, Turgay; Zafer Seker, Dursun

2018-05-01

The advancements in the photogrammetry and remote sensing technologies has made it possible to extract useful tangible information from data which plays a pivotal role in various application such as management and monitoring of forests and agricultural lands etc. This study aimed to evaluate the effectiveness of spectral signatures for extraction of tea gardens from 1 : 5000 scaled digital orthophoto maps obtained from Rize city in Turkey. First, the normalized difference vegetation index (NDVI) was derived from the input images to suppress the non-vegetation areas. NDVI values less than zero were discarded and the output images was normalized in the range 0-255. Individual pixels were then mapped into meaningful objects using global region growing technique. The resulting image was filtered and smoothed to reduce the impact of noise. Furthermore, geometrical constraints were applied to remove small objects (less than 500 pixels) followed by morphological opening operator to enhance the results. These objects served as building blocks for further image analysis. Finally, for the classification stage, a range of spectral values were empirically calculated for each band and applied on candidate objects to extract tea gardens. For accuracy assessment, we employed an area based similarity metric by overlapping obtained tea garden boundaries with the manually digitized tea garden boundaries created by experts of photogrammetry. The overall accuracy of the proposed method scored 89 % for tea gardens from 10 sample orthophoto maps. We concluded that exploiting the spectral signatures using object based analysis is an effective technique for extraction of dominant tree species from digital orthophoto maps.

System for objective assessment of image differences in digital cinema

NASA Astrophysics Data System (ADS)

Fliegel, Karel; Krasula, Lukáš; Páta, Petr; Myslík, Jiří; Pecák, Josef; Jícha, Marek

2014-09-01

There is high demand for quick digitization and subsequent image restoration of archived film records. Digitization is very urgent in many cases because various invaluable pieces of cultural heritage are stored on aging media. Only selected records can be reconstructed perfectly using painstaking manual or semi-automatic procedures. This paper aims to answer the question what are the quality requirements on the restoration process in order to obtain acceptably close visual perception of the digitally restored film in comparison to the original analog film copy. This knowledge is very important to preserve the original artistic intention of the movie producers. Subjective experiment with artificially distorted images has been conducted in order to answer the question what is the visual impact of common image distortions in digital cinema. Typical color and contrast distortions were introduced and test images were presented to viewers using digital projector. Based on the outcome of this subjective evaluation a system for objective assessment of image distortions has been developed and its performance tested. The system utilizes calibrated digital single-lens reflex camera and subsequent analysis of suitable features of images captured from the projection screen. The evaluation of captured image data has been optimized in order to obtain predicted differences between the reference and distorted images while achieving high correlation with the results of subjective assessment. The system can be used to objectively determine the difference between analog film and digital cinema images on the projection screen.

Digital image processing of vascular angiograms

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Beckenbach, E. S.; Blankenhorn, D. H.; Crawford, D. W.; Brooks, S. H.

1975-01-01

The paper discusses the estimation of the degree of atherosclerosis in the human femoral artery through the use of a digital image processing system for vascular angiograms. The film digitizer uses an electronic image dissector camera to scan the angiogram and convert the recorded optical density information into a numerical format. Another processing step involves locating the vessel edges from the digital image. The computer has been programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements are combined into an atherosclerosis index, which is found in a post-mortem study to correlate well with both visual and chemical estimates of atherosclerotic disease.

Digital implementation of a neural network for imaging

NASA Astrophysics Data System (ADS)

Wood, Richard; McGlashan, Alex; Yatulis, Jay; Mascher, Peter; Bruce, Ian

2012-10-01

This paper outlines the design and testing of a digital imaging system that utilizes an artificial neural network with unsupervised and supervised learning to convert streaming input (real time) image space into parameter space. The primary objective of this work is to investigate the effectiveness of using a neural network to significantly reduce the information density of streaming images so that objects can be readily identified by a limited set of primary parameters and act as an enhanced human machine interface (HMI). Many applications are envisioned including use in biomedical imaging, anomaly detection and as an assistive device for the visually impaired. A digital circuit was designed and tested using a Field Programmable Gate Array (FPGA) and an off the shelf digital camera. Our results indicate that the networks can be readily trained when subject to limited sets of objects such as the alphabet. We can also separate limited object sets with rotational and positional invariance. The results also show that limited visual fields form with only local connectivity.

EDITORIAL: Focus on Visualization in Physics FOCUS ON VISUALIZATION IN PHYSICS

NASA Astrophysics Data System (ADS)

Sanders, Barry C.; Senden, Tim; Springel, Volker

2008-12-01

Advances in physics are intimately connected with developments in a new technology, the telescope, precision clocks, even the computer all have heralded a shift in thinking. These landmark developments open new opportunities accelerating research and in turn new scientific directions. These technological drivers often correspond to new instruments, but equally might just as well flag a new mathematical tool, an algorithm or even means to visualize physics in a new way. Early on in this twenty-first century, scientific communities are just starting to explore the potential of digital visualization. Whether visualization is used to represent and communicate complex concepts, or to understand and interpret experimental data, or to visualize solutions to complex dynamical equations, the basic tools of visualization are shared in each of these applications and implementations. High-performance computing exemplifies the integration of visualization with leading research. Visualization is an indispensable tool for analyzing and interpreting complex three-dimensional dynamics as well as to diagnose numerical problems in intricate parallel calculation algorithms. The effectiveness of visualization arises by exploiting the unmatched capability of the human eye and visual cortex to process the large information content of images. In a brief glance, we recognize patterns or identify subtle features even in noisy data, something that is difficult or impossible to achieve with more traditional forms of data analysis. Importantly, visualizations guide the intuition of researchers and help to comprehend physical phenomena that lie far outside of direct experience. In fact, visualizations literally allow us to see what would otherwise remain completely invisible. For example, artificial imagery created to visualize the distribution of dark matter in the Universe has been instrumental to develop the notion of a cosmic web, and for helping to establish the current standard model of

The effects of extrinsic motivation on signature authorship opinions in forensic signature blind trials.

PubMed

Dewhurst, Tahnee N; Found, Bryan; Ballantyne, Kaye N; Rogers, Doug

2014-03-01

Expertise studies in forensic handwriting examination involve comparisons of Forensic Handwriting Examiners' (FHEs) opinions with lay-persons on blind tests. All published studies of this type have reported real and demonstrable skill differences between the specialist and lay groups. However, critics have proposed that any difference shown may be indicative of a lack of motivation on the part of lay participants, rather than a real difference in skill. It has been suggested that qualified FHEs would be inherently more motivated to succeed in blinded validation trials, as their professional reputations could be at risk, should they perform poorly on the task provided. Furthermore, critics suggest that lay-persons would be unlikely to be highly motivated to succeed, as they would have no fear of negative consequences should they perform badly. In an effort to investigate this concern, a blind signature trial was designed and administered to forty lay-persons. Participants were required to compare known (exemplar) signatures of an individual to questioned signatures and asked to express an opinion regarding whether the writer of the known signatures wrote each of the questioned signatures. The questioned signatures comprised a mixture of genuine, disguised and simulated signatures. The forty participants were divided into two separate groupings. Group 'A' were requested to complete the trial as directed and were advised that for each correct answer they would be financially rewarded, for each incorrect answer they would be financially penalized, and for each inconclusive opinion they would receive neither penalty nor reward. Group 'B' was requested to complete the trial as directed, with no mention of financial recompense or penalty. The results of this study do not support the proposition that motivation rather than skill difference is the source of the statistical difference in opinions between individuals' results in blinded signature proficiency trials. Crown

Processing of Visual Imagery by an Adaptive Model of the Visual System: Its Performance and its Significance. Final Report, June 1969-March 1970.

ERIC Educational Resources Information Center

Tallman, Oliver H.

A digital simulation of a model for the processing of visual images is derived from known aspects of the human visual system. The fundamental principle of computation suggested by a biological model is a transformation that distributes information contained in an input stimulus everywhere in a transform domain. Each sensory input contributes under…

Signature of Microbial Dysbiosis in Periodontitis.

PubMed

Meuric, Vincent; Le Gall-David, Sandrine; Boyer, Emile; Acuña-Amador, Luis; Martin, Bénédicte; Fong, Shao Bing; Barloy-Hubler, Frederique; Bonnaure-Mallet, Martine

2017-07-15

Periodontitis is driven by disproportionate host inflammatory immune responses induced by an imbalance in the composition of oral bacteria; this instigates microbial dysbiosis, along with failed resolution of the chronic destructive inflammation. The objectives of this study were to identify microbial signatures for health and chronic periodontitis at the genus level and to propose a model of dysbiosis, including the calculation of bacterial ratios. Published sequencing data obtained from several different studies (196 subgingival samples from patients with chronic periodontitis and 422 subgingival samples from healthy subjects) were pooled and subjected to a new microbiota analysis using the same Visualization and Analysis of Microbial Population Structures (VAMPS) pipeline, to identify microbiota specific to health and disease. Microbiota were visualized using CoNet and Cytoscape. Dysbiosis ratios, defined as the percentage of genera associated with disease relative to the percentage of genera associated with health, were calculated to distinguish disease from health. Correlations between the proposed dysbiosis ratio and the periodontal pocket depth were tested with a different set of data obtained from a recent study, to confirm the relevance of the ratio as a potential indicator of dysbiosis. Beta diversity showed significant clustering of periodontitis-associated microbiota, at the genus level, according to the clinical status and independent of the methods used. Specific genera ( Veillonella , Neisseria , Rothia , Corynebacterium , and Actinomyces ) were highly prevalent (>95%) in health, while other genera ( Eubacterium , Campylobacter , Treponema , and Tannerella ) were associated with chronic periodontitis. The calculation of dysbiosis ratios based on the relative abundance of the genera found in health versus periodontitis was tested. Nonperiodontitis samples were significantly identifiable by low ratios, compared to chronic periodontitis samples. When

Voluntary Enhancement of Neural Signatures of Affiliative Emotion Using fMRI Neurofeedback

PubMed Central

Moll, Jorge; Weingartner, Julie H.; Bado, Patricia; Basilio, Rodrigo; Sato, João R.; Melo, Bruno R.; Bramati, Ivanei E.; de Oliveira-Souza, Ricardo; Zahn, Roland

2014-01-01

In Ridley Scott’s film “Blade Runner”, empathy-detection devices are employed to measure affiliative emotions. Despite recent neurocomputational advances, it is unknown whether brain signatures of affiliative emotions, such as tenderness/affection, can be decoded and voluntarily modulated. Here, we employed multivariate voxel pattern analysis and real-time fMRI to address this question. We found that participants were able to use visual feedback based on decoded fMRI patterns as a neurofeedback signal to increase brain activation characteristic of tenderness/affection relative to pride, an equally complex control emotion. Such improvement was not observed in a control group performing the same fMRI task without neurofeedback. Furthermore, the neurofeedback-driven enhancement of tenderness/affection-related distributed patterns was associated with local fMRI responses in the septohypothalamic area and frontopolar cortex, regions previously implicated in affiliative emotion. This demonstrates that humans can voluntarily enhance brain signatures of tenderness/affection, unlocking new possibilities for promoting prosocial emotions and countering antisocial behavior. PMID:24847819

Designing Computer-Based Learning Contents: Influence of Digital Zoom on Attention

ERIC Educational Resources Information Center

Glaser, Manuela; Lengyel, Dominik; Toulouse, Catherine; Schwan, Stephan

2017-01-01

In the present study, we investigated the role of digital zoom as a tool for directing attention while looking at visual learning material. In particular, we analyzed whether minimal digital zoom functions similarly to a rhetorical device by cueing mental zooming of attention accordingly. Participants were presented either static film clips, film…

Comparing synthetic imagery with real imagery for visible signature analysis: human observer results

NASA Astrophysics Data System (ADS)

Culpepper, Joanne B.; Richards, Noel; Madden, Christopher S.; Winter, Neal; Wheaton, Vivienne C.

2017-10-01

Synthetic imagery could potentially enhance visible signature analysis by providing a wider range of target images in differing environmental conditions than would be feasible to collect in field trials. Achieving this requires a method for generating synthetic imagery that is both verified to be realistic and produces the same visible signature analysis results as real images. Is target detectability as measured by image metrics the same for real images and synthetic images of the same scene? Is target detectability as measured by human observer trials the same for real images and synthetic images of the same scene, and how realistic do the synthetic images need to be? In this paper we present the results of a small scale exploratory study on the second question: a photosimulation experiment conducted using digital photographs and synthetic images generated of the same scene. Two sets of synthetic images were created: a high fidelity set created using an image generation tool, E-on Vue, and a low fidelity set created using a gaming engine, Unity 3D. The target detection results obtained using digital photographs were compared with those obtained using the two sets of synthetic images. There was a moderate correlation between the high fidelity synthetic image set and the real images in both the probability of correct detection (Pd: PCC = 0.58, SCC = 0.57) and mean search time (MST: PCC = 0.63, SCC = 0.61). There was no correlation between the low fidelity synthetic image set and the real images for the Pd, but a moderate correlation for MST (PCC = 0.67, SCC = 0.55).

Secure Obfuscation for Encrypted Group Signatures

PubMed Central

Fan, Hongfei; Liu, Qin

2015-01-01

In recent years, group signature techniques are widely used in constructing privacy-preserving security schemes for various information systems. However, conventional techniques keep the schemes secure only in normal black-box attack contexts. In other words, these schemes suppose that (the implementation of) the group signature generation algorithm is running in a platform that is perfectly protected from various intrusions and attacks. As a complementary to existing studies, how to generate group signatures securely in a more austere security context, such as a white-box attack context, is studied in this paper. We use obfuscation as an approach to acquire a higher level of security. Concretely, we introduce a special group signature functionality-an encrypted group signature, and then provide an obfuscator for the proposed functionality. A series of new security notions for both the functionality and its obfuscator has been introduced. The most important one is the average-case secure virtual black-box property w.r.t. dependent oracles and restricted dependent oracles which captures the requirement of protecting the output of the proposed obfuscator against collision attacks from group members. The security notions fit for many other specialized obfuscators, such as obfuscators for identity-based signatures, threshold signatures and key-insulated signatures. Finally, the correctness and security of the proposed obfuscator have been proven. Thereby, the obfuscated encrypted group signature functionality can be applied to variants of privacy-preserving security schemes and enhance the security level of these schemes. PMID:26167686

Characterizing Resident Space Object Earthshine Signature Variability

NASA Astrophysics Data System (ADS)

Van Cor, Jared D.

?m]over a sample of ROIs. Further analysis using EPIC imagery found a total albedo difference of +0.03% and a cross correlation of 0.656. Also compared to EPIC imagery it was found our heterogeneous Earth model produced a reflected Earthshine radiance RMSE of +/-28 [watts/m. 2sr?m] incident on diffuse sphericalRSOs, specular spherical RSOs, and diffuse flat plate RSOs with an altitude of 1000km; this resulted in an apparent magnitude error of +/-0.28. Furthermore, it was found our heterogeneous Earthmodel produced a reflected Earthshine radiance RMSE of +/-68 [watts/m. 2sr?m] for specular flat plate RSOs withan altitude of 1000km; this resulted in an apparent magnitude error of +/-0.68. The Earth objects were used in a workflow with the Digital Imaging and Remote Sensing Image Generation (DIRSIG) tool to explore the impact of a range of characteristic RSO geometries, geographies, orientations, and materials on the signatures from an RSO due to Earthshine. An apparent magnitude was calculated and used to quantify RSO Earthshine signature variability; this is discussed in terms of the RMSE and maximum deviations of visible RSO Earthshine apparent magnitude signatures comparing the homogeneous Earth model to heterogeneous Earth model. The homogeneous diffuse Earth object was shown to approximate visible RSO Earthshine apparent magnitude signatures from spheres with a RMSE in reflected Earthshine apparent magnitude of +/-0.4 and a maximum apparent magnitude difference of 1.09 when compared to the heterogeneous Earth model. Similarly for diffuse flat plates, the visible RSO Earthshine apparent magnitude signature RMSE was shown to be +/-0.64, with a maximum apparent magnitude difference of 0.82. For specular flat plates, the visible RSO Earthshine apparent magnitude signature RMSE was shown to be +/-0.97 with maximum apparent magnitude difference of 2.26. This thesis explored only a portion of the parameter dependencies of Earth shine, but has enabled a preliminary understanding

Are forward and backward recall the same? A dual-task study of digit recall.

PubMed

St Clair-Thompson, Helen L; Allen, Richard J

2013-05-01

There is some debate surrounding the cognitive resources underlying backward digit recall. Some researchers consider it to differ from forward digit recall due to the involvement of executive control, while others suggest that backward recall involves visuospatial resources. Five experiments therefore investigated the role of executive-attentional and visuospatial resources in both forward and backward digit recall. In the first, participants completed visuospatial 0-back and 2-back tasks during the encoding of information to be remembered. The concurrent tasks did not differentially disrupt performance on backward digit recall, relative to forward digit recall. Experiment 2 shifted concurrent load to the recall phase instead and, in this case, revealed a larger effect of both tasks on backward recall, relative to forwards recall, suggesting that backward recall may draw on additional resources during the recall phase and that these resources are visuospatial in nature. Experiments 3 and 4 then further investigated the role of visual processes in forward and backward recall using dynamic visual noise (DVN). In Experiment 3, DVN was presented during encoding of information to be remembered and had no effect upon performance. However, in Experiment 4, it was presented during the recall phase, and the results provided evidence of a role for visual imagery in backward digit recall. These results were replicated in Experiment 5, in which the same list length was used for forward and backward recall tasks. The findings are discussed in terms of both theoretical and practical implications.

Optical/digital identification/verification system based on digital watermarking technology

NASA Astrophysics Data System (ADS)

Herrigel, Alexander; Voloshynovskiy, Sviatoslav V.; Hrytskiv, Zenon D.

2000-06-01

This paper presents a new approach for the secure integrity verification of driver licenses, passports or other analogue identification documents. The system embeds (detects) the reference number of the identification document with the DCT watermark technology in (from) the owner photo of the identification document holder. During verification the reference number is extracted and compared with the reference number printed in the identification document. The approach combines optical and digital image processing techniques. The detection system must be able to scan an analogue driver license or passport, convert the image of this document into a digital representation and then apply the watermark verification algorithm to check the payload of the embedded watermark. If the payload of the watermark is identical with the printed visual reference number of the issuer, the verification was successful and the passport or driver license has not been modified. This approach constitutes a new class of application for the watermark technology, which was originally targeted for the copyright protection of digital multimedia data. The presented approach substantially increases the security of the analogue identification documents applied in many European countries.

Visualization and interaction tools for aerial photograph mosaics

NASA Astrophysics Data System (ADS)

Fernandes, João Pedro; Fonseca, Alexandra; Pereira, Luís; Faria, Adriano; Figueira, Helder; Henriques, Inês; Garção, Rita; Câmara, António

1997-05-01

This paper describes the development of a digital spatial library based on mosaics of digital orthophotos, called Interactive Portugal, that will enable users both to retrieve geospatial information existing in the Portuguese National System for Geographic Information World Wide Web server, and to develop local databases connected to the main system. A set of navigation, interaction, and visualization tools are proposed and discussed. They include sketching, dynamic sketching, and navigation capabilities over the digital orthophotos mosaics. Main applications of this digital spatial library are pointed out and discussed, namely for education, professional, and tourism markets. Future developments are considered. These developments are related to user reactions, technological advancements, and projects that also aim at delivering and exploring digital imagery on the World Wide Web. Future capabilities for site selection and change detection are also considered.

Signature Verification Based on Handwritten Text Recognition

NASA Astrophysics Data System (ADS)

Viriri, Serestina; Tapamo, Jules-R.

Signatures continue to be an important biometric trait because it remains widely used primarily for authenticating the identity of human beings. This paper presents an efficient text-based directional signature recognition algorithm which verifies signatures, even when they are composed of special unconstrained cursive characters which are superimposed and embellished. This algorithm extends the character-based signature verification technique. The experiments carried out on the GPDS signature database and an additional database created from signatures captured using the ePadInk tablet, show that the approach is effective and efficient, with a positive verification rate of 94.95%.

Images in Language: Metaphors and Metamorphoses. Visual Learning. Volume 1

ERIC Educational Resources Information Center

Benedek, Andras, Ed.; Nyiri, Kristof, Ed.

2011-01-01

Learning and teaching are faced with radically new challenges in today's rapidly changing world and its deeply transformed communicational environment. We are living in an era of images. Contemporary visual technology--film, video, interactive digital media--is promoting but also demanding a new approach to education: the age of visual learning…

The role of visual spatial attention in adult developmental dyslexia.

PubMed

Collis, Nathan L; Kohnen, Saskia; Kinoshita, Sachiko

2013-01-01

The present study investigated the nature of visual spatial attention deficits in adults with developmental dyslexia, using a partial report task with five-letter, digit, and symbol strings. Participants responded by a manual key press to one of nine alternatives, which included other characters in the string, allowing an assessment of position errors as well as intrusion errors. The results showed that the dyslexic adults performed significantly worse than age-matched controls with letter and digit strings but not with symbol strings. Both groups produced W-shaped serial position functions with letter and digit strings. The dyslexics' deficits with letter string stimuli were limited to position errors, specifically at the string-interior positions 2 and 4. These errors correlated with letter transposition reading errors (e.g., reading slat as "salt"), but not with the Rapid Automatized Naming (RAN) task. Overall, these results suggest that the dyslexic adults have a visual spatial attention deficit; however, the deficit does not reflect a reduced span in visual-spatial attention, but a deficit in processing a string of letters in parallel, probably due to difficulty in the coding of letter position.

Symbol Sense Behavior in Digital Activities

ERIC Educational Resources Information Center

Bokhove, Christian; Drijvers, Paul

2010-01-01

The algebraic expertise that mathematics education is aiming for includes both procedural skills and conceptual understanding. To capture the latter, notions such as symbol sense, gestalt view and visual salience have been developed. We wonder if digital activities can be designed that not only require procedural algebraic skills, but also invite…

Real time gamma-ray signature identifier

DOEpatents

Rowland, Mark [Alamo, CA; Gosnell, Tom B [Moraga, CA; Ham, Cheryl [Livermore, CA; Perkins, Dwight [Livermore, CA; Wong, James [Dublin, CA

2012-05-15

A real time gamma-ray signature/source identification method and system using principal components analysis (PCA) for transforming and substantially reducing one or more comprehensive spectral libraries of nuclear materials types and configurations into a corresponding concise representation/signature(s) representing and indexing each individual predetermined spectrum in principal component (PC) space, wherein an unknown gamma-ray signature may be compared against the representative signature to find a match or at least characterize the unknown signature from among all the entries in the library with a single regression or simple projection into the PC space, so as to substantially reduce processing time and computing resources and enable real-time characterization and/or identification.

Toward a hyperspectral optical signature of extra virgin olive oil

NASA Astrophysics Data System (ADS)

Mignani, A. G.; Ciaccheri, L.; Thienpont, H.; Ottevaere, H.; Attilio, C.; Cimato, A.

2007-05-01

Italian extra virgin olive oils bearing labels of certified area of origin were considered. Their multispectral digital signature was measured by means of absorption spectroscopy in the 200-1700 nm spectral range. The instrumentation was a fiber optic-based, cheap, and compact device. The spectral data were processed by means of multivariate analysis and plotted on a 2D classification map. The map showed sharp clusters according to the geographical origin of the oils, thus demonstrating the potentials of UV-VIS-NIR spectroscopy for optical fingerprinting. Then, the spectral data were correlated to the content of the most important fatty acids. The good fitting achieved demonstrated that the optical fingerprinting can be used also for predicting nutritional and chemical parameters.

Multiplicative processes in visual cognition

NASA Astrophysics Data System (ADS)

Credidio, H. F.; Teixeira, E. N.; Reis, S. D. S.; Moreira, A. A.; Andrade, J. S.

2014-03-01

The Central Limit Theorem (CLT) is certainly one of the most important results in the field of statistics. The simple fact that the addition of many random variables can generate the same probability curve, elucidated the underlying process for a broad spectrum of natural systems, ranging from the statistical distribution of human heights to the distribution of measurement errors, to mention a few. An extension of the CLT can be applied to multiplicative processes, where a given measure is the result of the product of many random variables. The statistical signature of these processes is rather ubiquitous, appearing in a diverse range of natural phenomena, including the distributions of incomes, body weights, rainfall, and fragment sizes in a rock crushing process. Here we corroborate results from previous studies which indicate the presence of multiplicative processes in a particular type of visual cognition task, namely, the visual search for hidden objects. Precisely, our results from eye-tracking experiments show that the distribution of fixation times during visual search obeys a log-normal pattern, while the fixational radii of gyration follow a power-law behavior.

Visual Literacy: An Institutional Imperative

ERIC Educational Resources Information Center

Metros, Susan E.; Woolsey, Kristina

2006-01-01

Academics have a long history of claiming and defending the superiority of verbal over visual for representing knowledge. By dismissing imagery as mere decoration, they have upheld the sanctity of print for academic discourse. However, in the last decade, digital technologies have broken down the barriers between words and pictures, and many of…

Cross-disciplinary Undergraduate Research: A Case Study in Digital Mapping, western Ireland

NASA Astrophysics Data System (ADS)

Whitmeyer, S. J.; de Paor, D. G.; Nicoletti, J.; Rivera, M.; Santangelo, B.; Daniels, J.

2008-12-01

As digital mapping technology becomes ever more advanced, field geologists spend a greater proportion of time learning digital methods relative to analyzing rocks and structures. To explore potential solutions to the time commitment implicit in learning digital field methods, we paired James Madison University (JMU) geology majors (experienced in traditional field techniques) with Worcester Polytechnic Institute (WPI) engineering students (experienced in computer applications) during a four week summer mapping project in Connemara, western Ireland. The project consisted of approximately equal parts digital field mapping (directed by the geology students), and lab-based map assembly, evaluation and formatting for virtual 3D terrains (directed by the engineering students). Students collected geologic data in the field using ruggedized handheld computers (Trimble GeoExplorer® series) with ArcPAD® software. Lab work initially focused on building geologic maps in ArcGIS® from the digital field data and then progressed to developing Google Earth-based visualizations of field data and maps. Challenges included exporting GIS data, such as locations and attributes, to KML tags for viewing in Google Earth, which we accomplished using a Linux bash script written by one of our engineers - a task outside the comfort zone of the average geology major. We also attempted to expand the scope of Google Earth by using DEMs of present-day geologically-induced landforms as representative models for paleo-geographic reconstructions of the western Ireland field area. As our integrated approach to digital field work progressed, we found that our digital field mapping produced data at a faster rate than could be effectively managed during our allotted time for lab work. This likely reflected the more developed methodology for digital field data collection, as compared with our lab-based attempts to develop new methods for 3D visualization of geologic maps. However, this experiment in

Visual investigation on the heat dissipation process of a heat sink by using digital holographic interferometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Bingjing; Zhao, Jianlin, E-mail: jlzhao@nwpu.edu.cn; Wang, Jun

2013-11-21

We present a method for visually and quantitatively investigating the heat dissipation process of plate-fin heat sinks by using digital holographic interferometry. A series of phase change maps reflecting the temperature distribution and variation trend of the air field surrounding heat sink during the heat dissipation process are numerically reconstructed based on double-exposure holographic interferometry. According to the phase unwrapping algorithm and the derived relationship between temperature and phase change of the detection beam, the full-field temperature distributions are quantitatively obtained with a reasonably high measurement accuracy. And then the impact of heat sink's channel width on the heat dissipationmore » performance in the case of natural convection is analyzed. In addition, a comparison between simulation and experiment results is given to verify the reliability of this method. The experiment results certify the feasibility and validity of the presented method in full-field, dynamical, and quantitative measurement of the air field temperature distribution, which provides a basis for analyzing the heat dissipation performance of plate-fin heat sinks.« less

Methods and systems for detecting abnormal digital traffic

DOEpatents

Goranson, Craig A [Kennewick, WA; Burnette, John R [Kennewick, WA

2011-03-22

Aspects of the present invention encompass methods and systems for detecting abnormal digital traffic by assigning characterizations of network behaviors according to knowledge nodes and calculating a confidence value based on the characterizations from at least one knowledge node and on weighting factors associated with the knowledge nodes. The knowledge nodes include a characterization model based on prior network information. At least one of the knowledge nodes should not be based on fixed thresholds or signatures. The confidence value includes a quantification of the degree of confidence that the network behaviors constitute abnormal network traffic.

Extrahepatic Arteries Originating from Hepatic Arteries: Analysis Using CT During Hepatic Arteriography and Visualization on Digital Subtraction Angiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozaki, Kumi, E-mail: ozakik-rad@umin.org; Kobayashi, Satoshi; Matsui, Osamu

PurposeTo investigate the prevalence and site of origin of extrahepatic arteries originating from hepatic arteries on early phase CT during hepatic arteriography (CTHA) was accessed. Visualization of these elements on digital subtraction hepatic angiography (DSHA) was assessed using CTHA images as a gold standard.Materials and MethodsA total of 943 patients (mean age 66.9 ± 10.3 years; male/female, 619/324) underwent CTHA and DSHA. The prevalence and site of origin of extrahepatic arteries were accessed using CTHA and visualized using DSHA.ResultsIn 924 (98.0%) patients, a total of 1555 extrahepatic branches, representing eight types, were found to originate from hepatic arteries on CTHA. CTHA indicated themore » following extrahepatic branch prevalence rates: right gastric artery, 890 (94.4%); falciform artery, 386 (40.9%); accessory left gastric artery, 161 (17.1%); left inferior phrenic artery (IPA), 43 (4.6%); posterior superior pancreaticoduodenal artery, 33 (3.5%); dorsal pancreatic artery, 26 (2.8%); duodenal artery, 12 (1.3%); and right IPA, 4 (0.4%). In addition, 383 patients (40.6%) had at least one undetectable branch on DSHA. The sensitivity, specificity, and accuracy of visualization on DSHA were as follows: RGA, 80.0, 86.8, and 80.4%; falciform artery, 53.9, 97.7, and 80.0%; accessory LGA, 64.6, 98.6, and 92.3%; left IPA, 76.7, 99.8, and 98.7%; PSPDA, 100, 99.7, and 99.9%; dorsal pancreatic artery, 57.7, 100, and 98.8%; duodenal artery, 8.3, 99.9, and 98.7%; and right IPA, 0, 100, and 99.6%, respectively.ConclusionExtrahepatic arteries originating from hepatic arteries were frequently identified on CTHA images. These arteries were frequently overlooked on DSHA.« less

Visual words for lip-reading

NASA Astrophysics Data System (ADS)

Hassanat, Ahmad B. A.; Jassim, Sabah

2010-04-01

In this paper, the automatic lip reading problem is investigated, and an innovative approach to providing solutions to this problem has been proposed. This new VSR approach is dependent on the signature of the word itself, which is obtained from a hybrid feature extraction method dependent on geometric, appearance, and image transform features. The proposed VSR approach is termed "visual words". The visual words approach consists of two main parts, 1) Feature extraction/selection, and 2) Visual speech feature recognition. After localizing face and lips, several visual features for the lips where extracted. Such as the height and width of the mouth, mutual information and the quality measurement between the DWT of the current ROI and the DWT of the previous ROI, the ratio of vertical to horizontal features taken from DWT of ROI, The ratio of vertical edges to horizontal edges of ROI, the appearance of the tongue and the appearance of teeth. Each spoken word is represented by 8 signals, one of each feature. Those signals maintain the dynamic of the spoken word, which contains a good portion of information. The system is then trained on these features using the KNN and DTW. This approach has been evaluated using a large database for different people, and large experiment sets. The evaluation has proved the visual words efficiency, and shown that the VSR is a speaker dependent problem.

A main path domain map as digital library interface

NASA Astrophysics Data System (ADS)

Demaine, Jeffrey

2009-01-01

The shift to electronic publishing of scientific journals is an opportunity for the digital library to provide non-traditional ways of accessing the literature. One method is to use citation metadata drawn from a collection of electronic journals to generate maps of science. These maps visualize the communication patterns in the collection, giving the user an easy-tograsp view of the semantic structure underlying the scientific literature. For this visualization to be understandable the complexity of the citation network must be reduced through an algorithm. This paper describes the Citation Pathfinder application and its integration into a prototype digital library. This application generates small-scale citation networks that expand upon the search results of the digital library. These domain maps are linked to the collection, creating an interface that is based on the communication patterns in science. The Main Path Analysis technique is employed to simplify these networks into linear, sequential structures. By identifying patterns that characterize the evolution of the research field, Citation Pathfinder uses citations to give users a deeper understanding of the scientific literature.

Image manipulation: Fraudulence in digital dental records: Study and review

PubMed Central

Chowdhry, Aman; Sircar, Keya; Popli, Deepika Bablani; Tandon, Ankita

2014-01-01

Introduction: In present-day times, freely available software allows dentists to tweak their digital records as never before. But, there is a fine line between acceptable enhancements and scientific delinquency. Aims and Objective: To manipulate digital images (used in forensic dentistry) of casts, lip prints, and bite marks in order to highlight tampering techniques and methods of detecting and preventing manipulation of digital images. Materials and Methods: Digital image records of forensic data (casts, lip prints, and bite marks photographed using Samsung Techwin L77 digital camera) were manipulated using freely available software. Results: Fake digital images can be created either by merging two or more digital images, or by altering an existing image. Discussion and Conclusion: Retouched digital images can be used for fraudulent purposes in forensic investigations. However, tools are available to detect such digital frauds, which are extremely difficult to assess visually. Thus, all digital content should mandatorily have attached metadata and preferably watermarking in order to avert their malicious re-use. Also, computer alertness, especially about imaging software's, should be promoted among forensic odontologists/dental professionals. PMID:24696587

Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wong, S.T.C.

The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound,more » electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.« less

27 CFR 17.6 - Signature authority.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Signature authority. 17.6... PRODUCTS General Provisions § 17.6 Signature authority. No claim, bond, tax return, or other required... other proper notification of signature authority has been filed with the TTB office where the required...

7 CFR 718.9 - Signature requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Signature requirements. 718.9 Section 718.9... MULTIPLE PROGRAMS General Provisions § 718.9 Signature requirements. (a) When a program authorized by this chapter or Chapter XIV of this title requires the signature of a producer; landowner; landlord; or tenant...

Smile line assessment comparing quantitative measurement and visual estimation.

PubMed

Van der Geld, Pieter; Oosterveld, Paul; Schols, Jan; Kuijpers-Jagtman, Anne Marie

2011-02-01

Esthetic analysis of dynamic functions such as spontaneous smiling is feasible by using digital videography and computer measurement for lip line height and tooth display. Because quantitative measurements are time-consuming, digital videography and semiquantitative (visual) estimation according to a standard categorization are more practical for regular diagnostics. Our objective in this study was to compare 2 semiquantitative methods with quantitative measurements for reliability and agreement. The faces of 122 male participants were individually registered by using digital videography. Spontaneous and posed smiles were captured. On the records, maxillary lip line heights and tooth display were digitally measured on each tooth and also visually estimated according to 3-grade and 4-grade scales. Two raters were involved. An error analysis was performed. Reliability was established with kappa statistics. Interexaminer and intraexaminer reliability values were high, with median kappa values from 0.79 to 0.88. Agreement of the 3-grade scale estimation with quantitative measurement showed higher median kappa values (0.76) than the 4-grade scale estimation (0.66). Differentiating high and gummy smile lines (4-grade scale) resulted in greater inaccuracies. The estimation of a high, average, or low smile line for each tooth showed high reliability close to quantitative measurements. Smile line analysis can be performed reliably with a 3-grade scale (visual) semiquantitative estimation. For a more comprehensive diagnosis, additional measuring is proposed, especially in patients with disproportional gingival display. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Thermal signature characteristics of vehicle/terrain interaction disturbances: implications for battlefield vehicle classification.

PubMed

Eastes, John W; Mason, George L; Kusinger, Alan E

2004-05-01

Thermal emissivity spectra (8-14 microm) of track impressions/background were determined in conjunction with operation of six military vehicle types, T-72 and M1 Tanks, an M2 Bradley Fighting Vehicle, a 5-ton truck, a D7 tractor, and a High Mobility Multipurpose Wheeled Vehicle (HMMWV), over diverse soil surfaces to determine if vehicle type could be related to track thermal signatures. Results suggest soil compaction and fragmentation/pulverization are primary parameters affecting track signatures and that soil and vehicle/terrain-contact type determine which parameter dominates. Steel-tracked vehicles exert relatively low ground-contact pressure but tend to fragment/pulverize soil more so than do rubber-tired vehicles, which tend mainly to compact. In quartz-rich, lean clay soil tracked vehicles produced impressions with spectral contrast of the quartz reststrahlen features decreased from that of the background. At the same time, 5-ton truck tracks exhibited increased contrast on the same surface, suggesting that steel tracks fragmented soil while rubber tires mainly produced compaction. The structure of materials such as sand and moist clay-rich river sediment makes them less subject to further fragmentation/pulverization; thus, compaction was the main factor affecting signatures in these media, and both tracked and wheeled vehicles created impressions with increased spectral contrast on these surfaces. These results suggest that remotely sensed thermal signatures could differentiate tracked and wheeled vehicles on terrain in many areas of the world of strategic interest. Significant applications include distinguishing visually/spectrally identical lightweight decoys from actual threat vehicles.

Glove-based approach to online signature verification.

PubMed

Kamel, Nidal S; Sayeed, Shohel; Ellis, Grant A

2008-06-01

Utilizing the multiple degrees of freedom offered by the data glove for each finger and the hand, a novel on-line signature verification system using the Singular Value Decomposition (SVD) numerical tool for signature classification and verification is presented. The proposed technique is based on the Singular Value Decomposition in finding r singular vectors sensing the maximal energy of glove data matrix A, called principal subspace, so the effective dimensionality of A can be reduced. Having modeled the data glove signature through its r-principal subspace, signature authentication is performed by finding the angles between the different subspaces. A demonstration of the data glove is presented as an effective high-bandwidth data entry device for signature verification. This SVD-based signature verification technique is tested and its performance is shown to be able to recognize forgery signatures with a false acceptance rate of less than 1.2%.

All-digital radar architecture

NASA Astrophysics Data System (ADS)

Molchanov, Pavlo A.

2014-10-01

All digital radar architecture requires exclude mechanical scan system. The phase antenna array is necessarily large because the array elements must be co-located with very precise dimensions and will need high accuracy phase processing system for aggregate and distribute T/R modules data to/from antenna elements. Even phase array cannot provide wide field of view. New nature inspired all digital radar architecture proposed. The fly's eye consists of multiple angularly spaced sensors giving the fly simultaneously thee wide-area visual coverage it needs to detect and avoid the threats around him. Fly eye radar antenna array consist multiple directional antennas loose distributed along perimeter of ground vehicle or aircraft and coupled with receiving/transmitting front end modules connected by digital interface to central processor. Non-steering antenna array allows creating all-digital radar with extreme flexible architecture. Fly eye radar architecture provides wide possibility of digital modulation and different waveform generation. Simultaneous correlation and integration of thousands signals per second from each point of surveillance area allows not only detecting of low level signals ((low profile targets), but help to recognize and classify signals (targets) by using diversity signals, polarization modulation and intelligent processing. Proposed all digital radar architecture with distributed directional antenna array can provide a 3D space vector to the jammer by verification direction of arrival for signals sources and as result jam/spoof protection not only for radar systems, but for communication systems and any navigation constellation system, for both encrypted or unencrypted signals, for not limited number or close positioned jammers.

48 CFR 804.101 - Contracting officer's signature.

Code of Federal Regulations, 2010 CFR

2010-10-01

... signature. 804.101 Section 804.101 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS GENERAL ADMINISTRATIVE MATTERS Contract Execution 804.101 Contracting officer's signature. (a) If a... signature. ...

The trustworthy digital camera: Restoring credibility to the photographic image

NASA Technical Reports Server (NTRS)

Friedman, Gary L.

1994-01-01

The increasing sophistication of computers has made digital manipulation of photographic images, as well as other digitally-recorded artifacts such as audio and video, incredibly easy to perform and increasingly difficult to detect. Today, every picture appearing in newspapers and magazines has been digitally altered to some degree, with the severity varying from the trivial (cleaning up 'noise' and removing distracting backgrounds) to the point of deception (articles of clothing removed, heads attached to other people's bodies, and the complete rearrangement of city skylines). As the power, flexibility, and ubiquity of image-altering computers continues to increase, the well-known adage that 'the photography doesn't lie' will continue to become an anachronism. A solution to this problem comes from a concept called digital signatures, which incorporates modern cryptographic techniques to authenticate electronic mail messages. 'Authenticate' in this case means one can be sure that the message has not been altered, and that the sender's identity has not been forged. The technique can serve not only to authenticate images, but also to help the photographer retain and enforce copyright protection when the concept of 'electronic original' is no longer meaningful.

AdaBoost-based on-line signature verifier

NASA Astrophysics Data System (ADS)

Hongo, Yasunori; Muramatsu, Daigo; Matsumoto, Takashi

2005-03-01

Authentication of individuals is rapidly becoming an important issue. The authors previously proposed a Pen-input online signature verification algorithm. The algorithm considers a writer"s signature as a trajectory of pen position, pen pressure, pen azimuth, and pen altitude that evolve over time, so that it is dynamic and biometric. Many algorithms have been proposed and reported to achieve accuracy for on-line signature verification, but setting the threshold value for these algorithms is a problem. In this paper, we introduce a user-generic model generated by AdaBoost, which resolves this problem. When user- specific models (one model for each user) are used for signature verification problems, we need to generate the models using only genuine signatures. Forged signatures are not available because imposters do not give forged signatures for training in advance. However, we can make use of another's forged signature in addition to the genuine signatures for learning by introducing a user generic model. And Adaboost is a well-known classification algorithm, making final decisions depending on the sign of the output value. Therefore, it is not necessary to set the threshold value. A preliminary experiment is performed on a database consisting of data from 50 individuals. This set consists of western-alphabet-based signatures provide by a European research group. In this experiment, our algorithm gives an FRR of 1.88% and an FAR of 1.60%. Since no fine-tuning was done, this preliminary result looks very promising.

Temporal windows in visual processing: "prestimulus brain state" and "poststimulus phase reset" segregate visual transients on different temporal scales.

PubMed

Wutz, Andreas; Weisz, Nathan; Braun, Christoph; Melcher, David

2014-01-22

Dynamic vision requires both stability of the current perceptual representation and sensitivity to the accumulation of sensory evidence over time. Here we study the electrophysiological signatures of this intricate balance between temporal segregation and integration in vision. Within a forward masking paradigm with short and long stimulus onset asynchronies (SOA), we manipulated the temporal overlap of the visual persistence of two successive transients. Human observers enumerated the items presented in the second target display as a measure of the informational capacity read-out from this partly temporally integrated visual percept. We observed higher β-power immediately before mask display onset in incorrect trials, in which enumeration failed due to stronger integration of mask and target visual information. This effect was timescale specific, distinguishing between segregation and integration of visual transients that were distant in time (long SOA). Conversely, for short SOA trials, mask onset evoked a stronger visual response when mask and targets were correctly segregated in time. Examination of the target-related response profile revealed the importance of an evoked α-phase reset for the segregation of those rapid visual transients. Investigating this precise mapping of the temporal relationships of visual signals onto electrophysiological responses highlights how the stream of visual information is carved up into discrete temporal windows that mediate between segregated and integrated percepts. Fragmenting the stream of visual information provides a means to stabilize perceptual events within one instant in time.

Stromal signatures in endometrioid endometrial carcinomas.

PubMed

Espinosa, Iñigo; Catasus, Lluis; D' Angelo, Emanuela; Mozos, Ana; Pedrola, Nuria; Bértolo, Cristina; Ferrer, Irene; Zannoni, Gian Franco; West, Robert B; van de Rijn, Matt; Matias-Guiu, Xavier; Prat, Jaime

2014-04-01

The pattern of myometrial invasion in endometrioid endometrial carcinomas varies considerably; ie, from widely scattered glands and cell nests, often associated with a fibromyxoid stromal reaction (desmoplasia) and/or a lymphocytic infiltrate, to invasive glands with little or no stromal response. Recently, two distinct stromal signatures derived from a macrophage response (colony-stimulating factor 1, CSF1) and a fibroblastic response (desmoid-type fibromatosis, DTF) were identified in breast carcinomas and correlated with clinicopathologic features including outcome. In this study, we explored whether these stromal signatures also apply to endometrioid carcinomas and how their expression patterns correlated with morphologic changes. We studied the stromal signatures both by immunohistochemistry and in situ hybridization in 98 primary endometrioid carcinomas with (87 cases) and without (11 cases) myometrial invasion as well as in the corresponding regional lymph nodes metatases of 9 myoinvasive tumors. Desmoplasia correlated positively with the DTF expression signature. Likewise, mononuclear infiltrates were found in the stroma of tumors expressing CSF1. Twenty-four out of eighty-seven (27%) myoinvasive endometrioid carcinomas were positive for the macrophage signature and thirteen out of eighty-seven (15%) expressed the fibroblast signature. Eleven additional cases were positive for both DTF and CSF1 signatures (11/87; 13%). However, over half of the cases (39/87; 45%) and the majority of the non-myoinvasive tumors (8/11; 73%) failed to express any of the two stromal signatures. The macrophage response (CSF1) was associated with higher tumor grade, lymphovascular invasion, and PIK3CA mutations (P<0.05). There was a concordance in the expression of the CSF1 signature in the primary tumors and their corresponding lymph node metastases. This study is the first characterization of stromal signatures in endometrioid carcinomas. Our findings shed new light on the

Combinational Circuit Obfuscation Through Power Signature Manipulation

DTIC Science & Technology

2011-06-01

Algorithm produced by SID . . . . . . . . . . . . . . . . . . . . . . 80 Appendix B . Power Signature Estimation Results 2 . . . . . . . . . . 85 B .1 Power...Signature for c264 Circuit Variant per Algorithm produced by SPICE Simulation . . . . . . . . . . . . . . 85 B .2 Power Signature for c5355 and c499...Smart SSR selecting rear level components and gates with 1000 iterations . . . . . . . . . 84 B .1. Power Signature for c264 By Random Sequence

A novel genome signature based on inter-nucleotide distances profiles for visualization of metagenomic data

NASA Astrophysics Data System (ADS)

Xie, Xian-Hua; Yu, Zu-Guo; Ma, Yuan-Lin; Han, Guo-Sheng; Anh, Vo

2017-09-01

There has been a growing interest in visualization of metagenomic data. The present study focuses on the visualization of metagenomic data using inter-nucleotide distances profile. We first convert the fragment sequences into inter-nucleotide distances profiles. Then we analyze these profiles by principal component analysis. Finally the principal components are used to obtain the 2-D scattered plot according to their source of species. We name our method as inter-nucleotide distances profiles (INP) method. Our method is evaluated on three benchmark data sets used in previous published papers. Our results demonstrate that the INP method is good, alternative and efficient for visualization of metagenomic data.

Creativity in the Age of Technology: Measuring the Digital Creativity of Millennials

ERIC Educational Resources Information Center

Hoffmann, Jessica; Ivcevic, Zorana; Brackett, Marc

2016-01-01

Digital technology and its many uses form an emerging domain of creative expression for adolescents and young adults. To date, measures of self-reported creative behavior cover more traditional forms of creativity, including visual art, music, or writing, but do not include creativity in the digital domain. This article introduces a new measure,…

Applying Strategic Visualization(Registered Trademark) to Lunar and Planetary Mission Design

NASA Technical Reports Server (NTRS)

Frassanito, John R.; Cooke, D. R.

2002-01-01

NASA teams, such as the NASA Exploration Team (NEXT), utilize advanced computational visualization processes to develop mission designs and architectures for lunar and planetary missions. One such process, Strategic Visualization (trademark), is a tool used extensively to help mission designers visualize various design alternatives and present them to other participants of their team. The participants, which may include NASA, industry, and the academic community, are distributed within a virtual network. Consequently, computer animation and other digital techniques provide an efficient means to communicate top-level technical information among team members. Today,Strategic Visualization(trademark) is used extensively both in the mission design process within the technical community, and to communicate the value of space exploration to the general public. Movies and digital images have been generated and shown on nationally broadcast television and the Internet, as well as in magazines and digital media. In our presentation will show excerpts of a computer-generated animation depicting the reference Earth/Moon L1 Libration Point Gateway architecture. The Gateway serves as a staging corridor for human expeditions to the lunar poles and other surface locations. Also shown are crew transfer systems and current reference lunar excursion vehicles as well as the Human and robotic construction of an inflatable telescope array for deployment to the Sun/Earth Libration Point.

25 CFR 213.10 - Lessor's signature.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Lessor's signature. 213.10 Section 213.10 Indians BUREAU... MEMBERS OF FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING How to Acquire Leases § 213.10 Lessor's signature... thumbprint which shall be designated as “right” or “left” thumbmark. Such signatures must be witnessed by two...

Attack and improvements of fair quantum blind signature schemes

NASA Astrophysics Data System (ADS)

Zou, Xiangfu; Qiu, Daowen

2013-06-01

Blind signature schemes allow users to obtain the signature of a message while the signer learns neither the message nor the resulting signature. Therefore, blind signatures have been used to realize cryptographic protocols providing the anonymity of some participants, such as: secure electronic payment systems and electronic voting systems. A fair blind signature is a form of blind signature which the anonymity could be removed with the help of a trusted entity, when this is required for legal reasons. Recently, a fair quantum blind signature scheme was proposed and thought to be safe. In this paper, we first point out that there exists a new attack on fair quantum blind signature schemes. The attack shows that, if any sender has intercepted any valid signature, he (she) can counterfeit a valid signature for any message and can not be traced by the counterfeited blind signature. Then, we construct a fair quantum blind signature scheme by improved the existed one. The proposed fair quantum blind signature scheme can resist the preceding attack. Furthermore, we demonstrate the security of the proposed fair quantum blind signature scheme and compare it with the other one.

Spectral signature selection for mapping unvegetated soils

NASA Technical Reports Server (NTRS)

May, G. A.; Petersen, G. W.

1975-01-01

Airborne multispectral scanner data covering the wavelength interval from 0.40-2.60 microns were collected at an altitude of 1000 m above the terrain in southeastern Pennsylvania. Uniform training areas were selected within three sites from this flightline. Soil samples were collected from each site and a procedure developed to allow assignment of scan line and element number from the multispectral scanner data to each sampling location. These soil samples were analyzed on a spectrophotometer and laboratory spectral signatures were derived. After correcting for solar radiation and atmospheric attenuation, the laboratory signatures were compared to the spectral signatures derived from these same soils using multispectral scanner data. Both signatures were used in supervised and unsupervised classification routines. Computer-generated maps using the laboratory and multispectral scanner derived signatures resulted in maps that were similar to maps resulting from field surveys. Approximately 90% agreement was obtained between classification maps produced using multispectral scanner derived signatures and laboratory derived signatures.

Genome signature analysis of thermal virus metagenomes reveals Archaea and thermophilic signatures.

PubMed

Pride, David T; Schoenfeld, Thomas

2008-09-17

Metagenomic analysis provides a rich source of biological information for otherwise intractable viral communities. However, study of viral metagenomes has been hampered by its nearly complete reliance on BLAST algorithms for identification of DNA sequences. We sought to develop algorithms for examination of viral metagenomes to identify the origin of sequences independent of BLAST algorithms. We chose viral metagenomes obtained from two hot springs, Bear Paw and Octopus, in Yellowstone National Park, as they represent simple microbial populations where comparatively large contigs were obtained. Thermal spring metagenomes have high proportions of sequences without significant Genbank homology, which has hampered identification of viruses and their linkage with hosts. To analyze each metagenome, we developed a method to classify DNA fragments using genome signature-based phylogenetic classification (GSPC), where metagenomic fragments are compared to a database of oligonucleotide signatures for all previously sequenced Bacteria, Archaea, and viruses. From both Bear Paw and Octopus hot springs, each assembled contig had more similarity to other metagenome contigs than to any sequenced microbial genome based on GSPC analysis, suggesting a genome signature common to each of these extreme environments. While viral metagenomes from Bear Paw and Octopus share some similarity, the genome signatures from each locale are largely unique. GSPC using a microbial database predicts most of the Octopus metagenome has archaeal signatures, while bacterial signatures predominate in Bear Paw; a finding consistent with those of Genbank BLAST. When using a viral database, the majority of the Octopus metagenome is predicted to belong to archaeal virus Families Globuloviridae and Fuselloviridae, while none of the Bear Paw metagenome is predicted to belong to archaeal viruses. As expected, when microbial and viral databases are combined, each of the Octopus and Bear Paw metagenomic contigs

A Forest Landscape Visualization System

Treesearch

Tim McDonald; Bryce Stokes

1998-01-01

A forest landscape visualization system was developed and used in creating realistic images depicting how an area might appear if harvested. The system uses a ray-tracing renderer to draw model trees on a virtual landscape. The system includes components to create landscape surfaces from digital elevation data, populate/cut trees within (polygonal) areas, and convert...

Data sonification and sound visualization.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaper, H. G.; Tipei, S.; Wiebel, E.

1999-07-01

Sound can help us explore and analyze complex data sets in scientific computing. The authors describe a digital instrument for additive sound synthesis (Diass) and a program to visualize sounds in a virtual reality environment (M4Cave). Both are part of a comprehensive music composition environment that includes additional software for computer-assisted composition and automatic music notation.

Mapping the Space of Genomic Signatures

PubMed Central

Kari, Lila; Hill, Kathleen A.; Sayem, Abu S.; Karamichalis, Rallis; Bryans, Nathaniel; Davis, Katelyn; Dattani, Nikesh S.

2015-01-01

We propose a computational method to measure and visualize interrelationships among any number of DNA sequences allowing, for example, the examination of hundreds or thousands of complete mitochondrial genomes. An "image distance" is computed for each pair of graphical representations of DNA sequences, and the distances are visualized as a Molecular Distance Map: Each point on the map represents a DNA sequence, and the spatial proximity between any two points reflects the degree of structural similarity between the corresponding sequences. The graphical representation of DNA sequences utilized, Chaos Game Representation (CGR), is genome- and species-specific and can thus act as a genomic signature. Consequently, Molecular Distance Maps could inform species identification, taxonomic classifications and, to a certain extent, evolutionary history. The image distance employed, Structural Dissimilarity Index (DSSIM), implicitly compares the occurrences of oligomers of length up to k (herein k = 9) in DNA sequences. We computed DSSIM distances for more than 5 million pairs of complete mitochondrial genomes, and used Multi-Dimensional Scaling (MDS) to obtain Molecular Distance Maps that visually display the sequence relatedness in various subsets, at different taxonomic levels. This general-purpose method does not require DNA sequence alignment and can thus be used to compare similar or vastly different DNA sequences, genomic or computer-generated, of the same or different lengths. We illustrate potential uses of this approach by applying it to several taxonomic subsets: phylum Vertebrata, (super)kingdom Protista, classes Amphibia-Insecta-Mammalia, class Amphibia, and order Primates. This analysis of an extensive dataset confirms that the oligomer composition of full mtDNA sequences can be a source of taxonomic information. This method also correctly finds the mtDNA sequences most closely related to that of the anatomically modern human (the Neanderthal, the Denisovan

Too little, too late: reduced visual span and speed characterize pure alexia.

PubMed

Starrfelt, Randi; Habekost, Thomas; Leff, Alexander P

2009-12-01

Whether normal word reading includes a stage of visual processing selectively dedicated to word or letter recognition is highly debated. Characterizing pure alexia, a seemingly selective disorder of reading, has been central to this debate. Two main theories claim either that 1) Pure alexia is caused by damage to a reading specific brain region in the left fusiform gyrus or 2) Pure alexia results from a general visual impairment that may particularly affect simultaneous processing of multiple items. We tested these competing theories in 4 patients with pure alexia using sensitive psychophysical measures and mathematical modeling. Recognition of single letters and digits in the central visual field was impaired in all patients. Visual apprehension span was also reduced for both letters and digits in all patients. The only cortical region lesioned across all 4 patients was the left fusiform gyrus, indicating that this region subserves a function broader than letter or word identification. We suggest that a seemingly pure disorder of reading can arise due to a general reduction of visual speed and span, and explain why this has a disproportionate impact on word reading while recognition of other visual stimuli are less obviously affected.

Too Little, Too Late: Reduced Visual Span and Speed Characterize Pure Alexia

PubMed Central

Habekost, Thomas; Leff, Alexander P.

2009-01-01

Whether normal word reading includes a stage of visual processing selectively dedicated to word or letter recognition is highly debated. Characterizing pure alexia, a seemingly selective disorder of reading, has been central to this debate. Two main theories claim either that 1) Pure alexia is caused by damage to a reading specific brain region in the left fusiform gyrus or 2) Pure alexia results from a general visual impairment that may particularly affect simultaneous processing of multiple items. We tested these competing theories in 4 patients with pure alexia using sensitive psychophysical measures and mathematical modeling. Recognition of single letters and digits in the central visual field was impaired in all patients. Visual apprehension span was also reduced for both letters and digits in all patients. The only cortical region lesioned across all 4 patients was the left fusiform gyrus, indicating that this region subserves a function broader than letter or word identification. We suggest that a seemingly pure disorder of reading can arise due to a general reduction of visual speed and span, and explain why this has a disproportionate impact on word reading while recognition of other visual stimuli are less obviously affected. PMID:19366870

E-Readers and Visual Fatigue

PubMed Central

Benedetto, Simone; Drai-Zerbib, Véronique; Pedrotti, Marco; Tissier, Geoffrey; Baccino, Thierry

2013-01-01

The mass digitization of books is changing the way information is created, disseminated and displayed. Electronic book readers (e-readers) generally refer to two main display technologies: the electronic ink (E-ink) and the liquid crystal display (LCD). Both technologies have advantages and disadvantages, but the question whether one or the other triggers less visual fatigue is still open. The aim of the present research was to study the effects of the display technology on visual fatigue. To this end, participants performed a longitudinal study in which two last generation e-readers (LCD, E-ink) and paper book were tested in three different prolonged reading sessions separated by - on average - ten days. Results from both objective (Blinks per second) and subjective (Visual Fatigue Scale) measures suggested that reading on the LCD (Kindle Fire HD) triggers higher visual fatigue with respect to both the E-ink (Kindle Paperwhite) and the paper book. The absence of differences between E-ink and paper suggests that, concerning visual fatigue, the E-ink is indeed very similar to the paper. PMID:24386252

Stereoscopic applications for design visualization

NASA Astrophysics Data System (ADS)

Gilson, Kevin J.

2007-02-01

Advances in display technology and 3D design visualization applications have made real-time stereoscopic visualization of architectural and engineering projects a reality. Parsons Brinkerhoff (PB) is a transportation consulting firm that has used digital visualization tools from their inception and has helped pioneer the application of those tools to large scale infrastructure projects. PB is one of the first Architecture/Engineering/Construction (AEC) firms to implement a CAVE- an immersive presentation environment that includes stereoscopic rear-projection capability. The firm also employs a portable stereoscopic front-projection system, and shutter-glass systems for smaller groups. PB is using commercial real-time 3D applications in combination with traditional 3D modeling programs to visualize and present large AEC projects to planners, clients and decision makers in stereo. These presentations create more immersive and spatially realistic presentations of the proposed designs. This paper will present the basic display tools and applications, and the 3D modeling techniques PB is using to produce interactive stereoscopic content. The paper will discuss several architectural and engineering design visualizations we have produced.

Do You Hear What I See? Assessing Accessibility of Digital Commons and CONTENTdm

ERIC Educational Resources Information Center

Walker, Wendy; Keenan, Teressa

2015-01-01

This article discusses the accessibility of two content management systems, Berkeley Electronic Press's Digital Commons and OCLC's CONTENTdm, widely used in libraries to host institutional repository and digital collections content. Based on observations by a visually impaired student who used the JAWS screen reader to view the design and display…

Critical Perspectives on Youth Digital Media Production: "Voice" and Representation in Educational Contexts

ERIC Educational Resources Information Center

Dahya, Negin

2017-01-01

This paper offers a critical discussion on voice and representation in youth digital media production in educational settings. The paper builds on existing calls from digital media and visual studies scholars to approach youth-made media with greater attention to context in production practices. In this discussion, the author addresses the…

Is digital photography an accurate and precise method for measuring range of motion of the shoulder and elbow?

PubMed

Russo, Russell R; Burn, Matthew B; Ismaily, Sabir K; Gerrie, Brayden J; Han, Shuyang; Alexander, Jerry; Lenherr, Christopher; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

2018-03-01

Accurate measurements of shoulder and elbow motion are required for the management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. Using infrared motion capture analysis as the reference standard, shoulder flexion/abduction/internal rotation/external rotation and elbow flexion/extension were measured using visual estimation, goniometry, and digital photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard (motion capture analysis), while precision was defined by the proportion of measurements within the authors' definition of clinical significance (10° for all motions except for elbow extension where 5° was used). Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. Although statistically significant differences were found in measurement accuracy between the three techniques, none of these differences met the authors' definition of clinical significance. Precision of the measurements was significantly higher for both digital photography (shoulder abduction [93% vs. 74%, p < 0.001], shoulder internal rotation [97% vs. 83%, p = 0.001], and elbow flexion [93% vs. 65%, p < 0.001]) and goniometry (shoulder abduction [92% vs. 74%, p < 0.001] and shoulder internal rotation [94% vs. 83%, p = 0.008]) than visual estimation. Digital photography was more precise than goniometry for measurements of elbow flexion only [93% vs. 76%, p < 0.001]. There was no clinically significant difference in measurement accuracy between the three techniques for shoulder and elbow motion. Digital photography showed higher measurement precision compared to visual estimation for shoulder abduction, shoulder

From Newton to Gates--Digital Principia

ERIC Educational Resources Information Center

Beckwith, E. George; Cunniff, Daniel T.

2008-01-01

Computers are becoming the norm for teaching and learning. The Internet gives people ready access to text, visual and audio messages from around the world. For teachers, content is critical and the future dictates the need for major changes in the role of the teacher and learner. Today's digital tools and video games have proven to be well known…

The Speed of Serial Attention Shifts in Visual Search: Evidence from the N2pc Component.

PubMed

Grubert, Anna; Eimer, Martin

2016-02-01

Finding target objects among distractors in visual search display is often assumed to be based on sequential movements of attention between different objects. However, the speed of such serial attention shifts is still under dispute. We employed a search task that encouraged the successive allocation of attention to two target objects in the same search display and measured N2pc components to determine how fast attention moved between these objects. Each display contained one digit in a known color (fixed-color target) and another digit whose color changed unpredictably across trials (variable-color target) together with two gray distractor digits. Participants' task was to find the fixed-color digit and compare its numerical value with that of the variable-color digit. N2pc components to fixed-color targets preceded N2pc components to variable-color digits, demonstrating that these two targets were indeed selected in a fixed serial order. The N2pc to variable-color digits emerged approximately 60 msec after the N2pc to fixed-color digits, which shows that attention can be reallocated very rapidly between different target objects in the visual field. When search display durations were increased, thereby relaxing the temporal demands on serial selection, the two N2pc components to fixed-color and variable-color targets were elicited within 90 msec of each other. Results demonstrate that sequential shifts of attention between different target locations can operate very rapidly at speeds that are in line with the assumptions of serial selection models of visual search.

Acoustic/infrasonic rocket engine signatures

NASA Astrophysics Data System (ADS)

Tenney, Stephen M.; Noble, John M.; Whitaker, Rodney W.; ReVelle, Douglas O.

2003-09-01

Infrasonics offers the potential of long-range acoustic detection of explosions, missiles and even sounds created by manufacturing plants. The atmosphere attenuates acoustic energy above 20 Hz quite rapidly, but signals below 10 Hz can propagate to long ranges. Space shuttle launches have been detected infrasonically from over 1000 km away and the Concorde airliner from over 400 km. This technology is based on microphones designed to respond to frequencies from .1 to 300 Hz that can be operated outdoors for extended periods of time with out degrading their performance. The US Army Research Laboratory and Los Alamos National Laboratory have collected acoustic and infrasonic signatures of static engine testing of two missiles. Signatures were collected of a SCUD missile engine at Huntsville, AL and a Minuteman engine at Edwards AFB. The engines were fixed vertically in a test stand during the burn. We will show the typical time waveform signals of these static tests and spectrograms for each type. High resolution, 24-bit data were collected at 512 Hz and 16-bit acoustic data at 10 kHz. Edwards data were recorded at 250 Hz and 50 Hz using a Geotech Instruments 24 bit digitizer. Ranges from the test stand varied from 1 km to 5 km. Low level and upper level meteorological data was collected to provide full details of atmospheric propagation during the engine test. Infrasonic measurements were made with the Chaparral Physics Model 2 microphone with porous garden hose attached for wind noise suppression. A B&K microphone was used for high frequency acoustic measurements. Results show primarily a broadband signal with distinct initiation and completion points. There appear to be features present in the signals that would allow identification of missile type. At 5 km the acoustic/infrasonic signal was clearly present. Detection ranges for the types of missile signatures measured will be predicted based on atmospheric modeling. As part of an experiment conducted by ARL

Semantically transparent fingerprinting for right protection of digital cinema

NASA Astrophysics Data System (ADS)

Wu, Xiaolin

2003-06-01

Digital cinema, a new frontier and crown jewel of digital multimedia, has the potential of revolutionizing the science, engineering and business of movie production and distribution. The advantages of digital cinema technology over traditional analog technology are numerous and profound. But without effective and enforceable copyright protection measures, digital cinema can be more susceptible to widespread piracy, which can dampen or even prevent the commercial deployment of digital cinema. In this paper we propose a novel approach of fingerprinting each individual distribution copy of a digital movie for the purpose of tracing pirated copies back to their source. The proposed fingerprinting technique presents a fundamental departure from the traditional digital watermarking/fingerprinting techniques. Its novelty and uniqueness lie in a so-called semantic or subjective transparency property. The fingerprints are created by editing those visual and audio attributes that can be modified with semantic and subjective transparency to the audience. Semantically-transparent fingerprinting or watermarking is the most robust kind among all existing watermarking techniques, because it is content-based not sample-based, and semantically-recoverable not statistically-recoverable.

A New Approach to Threshold Attribute Based Signatures

DTIC Science & Technology

2011-01-01

Inspired by developments in attribute based encryption and signatures, there has recently been a spurtof progress in the direction of threshold ...attribute based signatures (t-ABS). In this work we propose anovel approach to construct threshold attribute based signatures inspired by ring signatures...Thresholdattribute based signatures, dened by a (t; n) threshold predicate, ensure that the signer holds atleastt out of a specied set of n attributes

Faceted Visualization of Three Dimensional Neuroanatomy By Combining Ontology with Faceted Search

PubMed Central

Veeraraghavan, Harini; Miller, James V.

2013-01-01

In this work, we present a faceted-search based approach for visualization of anatomy by combining a three dimensional digital atlas with an anatomy ontology. Specifically, our approach provides a drill-down search interface that exposes the relevant pieces of information (obtained by searching the ontology) for a user query. Hence, the user can produce visualizations starting with minimally specified queries. Furthermore, by automatically translating the user queries into the controlled terminology our approach eliminates the need for the user to use controlled terminology. We demonstrate the scalability of our approach using an abdominal atlas and the same ontology. We implemented our visualization tool on the opensource 3D Slicer software. We present results of our visualization approach by combining a modified Foundational Model of Anatomy (FMA) ontology with the Surgical Planning Laboratory (SPL) Brain 3D digital atlas, and geometric models specific to patients computed using the SPL brain tumor dataset. PMID:24006207

Faceted visualization of three dimensional neuroanatomy by combining ontology with faceted search.

PubMed

Veeraraghavan, Harini; Miller, James V

2014-04-01

In this work, we present a faceted-search based approach for visualization of anatomy by combining a three dimensional digital atlas with an anatomy ontology. Specifically, our approach provides a drill-down search interface that exposes the relevant pieces of information (obtained by searching the ontology) for a user query. Hence, the user can produce visualizations starting with minimally specified queries. Furthermore, by automatically translating the user queries into the controlled terminology our approach eliminates the need for the user to use controlled terminology. We demonstrate the scalability of our approach using an abdominal atlas and the same ontology. We implemented our visualization tool on the opensource 3D Slicer software. We present results of our visualization approach by combining a modified Foundational Model of Anatomy (FMA) ontology with the Surgical Planning Laboratory (SPL) Brain 3D digital atlas, and geometric models specific to patients computed using the SPL brain tumor dataset.

General Conversion for Obtaining Strongly Existentially Unforgeable Signatures

NASA Astrophysics Data System (ADS)

Teranishi, Isamu; Oyama, Takuro; Ogata, Wakaha

We say that a signature scheme is strongly existentially unforgeable (SEU) if no adversary, given message/signature pairs adaptively, can generate a signature on a new message or a new signature on a previously signed message. We propose a general and efficient conversion in the standard model that transforms a secure signature scheme to SEU signature scheme. In order to construct that conversion, we use a chameleon commitment scheme. Here a chameleon commitment scheme is a variant of commitment scheme such that one can change the committed value after publishing the commitment if one knows the secret key. We define the chosen message security notion for the chameleon commitment scheme, and show that the signature scheme transformed by our proposed conversion satisfies the SEU property if the chameleon commitment scheme is chosen message secure. By modifying the proposed conversion, we also give a general and efficient conversion in the random oracle model, that transforms a secure signature scheme into a SEU signature scheme. This second conversion also uses a chameleon commitment scheme but only requires the key only attack security for it.

A Secure and Efficient Threshold Group Signature Scheme

NASA Astrophysics Data System (ADS)

Zhang, Yansheng; Wang, Xueming; Qiu, Gege

The paper presents a secure and efficient threshold group signature scheme aiming at two problems of current threshold group signature schemes: conspiracy attack and inefficiency. Scheme proposed in this paper takes strategy of separating designed clerk who is responsible for collecting and authenticating each individual signature from group, the designed clerk don't participate in distribution of group secret key and has his own public key and private key, designed clerk needs to sign part information of threshold group signature after collecting signatures. Thus verifier has to verify signature of the group after validating signature of the designed clerk. This scheme is proved to be secure against conspiracy attack at last and is more efficient by comparing with other schemes.

Toward a digital camera to rival the human eye

NASA Astrophysics Data System (ADS)

Skorka, Orit; Joseph, Dileepan

2011-07-01

All things considered, electronic imaging systems do not rival the human visual system despite notable progress over 40 years since the invention of the CCD. This work presents a method that allows design engineers to evaluate the performance gap between a digital camera and the human eye. The method identifies limiting factors of the electronic systems by benchmarking against the human system. It considers power consumption, visual field, spatial resolution, temporal resolution, and properties related to signal and noise power. A figure of merit is defined as the performance gap of the weakest parameter. Experimental work done with observers and cadavers is reviewed to assess the parameters of the human eye, and assessment techniques are also covered for digital cameras. The method is applied to 24 modern image sensors of various types, where an ideal lens is assumed to complete a digital camera. Results indicate that dynamic range and dark limit are the most limiting factors. The substantial functional gap, from 1.6 to 4.5 orders of magnitude, between the human eye and digital cameras may arise from architectural differences between the human retina, arranged in a multiple-layer structure, and image sensors, mostly fabricated in planar technologies. Functionality of image sensors may be significantly improved by exploiting technologies that allow vertical stacking of active tiers.

Digital image analysis agrees with visual estimates of adult bone marrow trephine biopsy cellularity.

PubMed

Hagiya, A S; Etman, A; Siddiqi, I N; Cen, S; Matcuk, G R; Brynes, R K; Salama, M E

2018-04-01

Evaluation of cellularity is an essential component of bone marrow trephine biopsy examination. The standard practice is to report the results as visual estimates (VE). Digital image analysis (DIA) offers the promise of more objective measurements of cellularity. Adult bone marrow trephine biopsy sections were assessed for cellularity by VE. Sections were scanned using an Aperio AT2 Scanscope and analyzed using a Cytonuclear (version 1.4) algorithm on halo software. Intraclass correlation (ICC) was used to assess relatedness between VE and DIA, and between MRI and DIA for a separate subset of patients. Trephine biopsy sections from a subset of patients with bone marrow biopsies uninvolved by malignancy were assessed for age-related changes. Interobserver VE agreement was good to excellent. The ICC value was 0.81 for VE and DIA, and 0.50 for MRI and DIA. Linearity studies showed no statistically significant trend for age-related changes in cellularity in our cohort (r = -.29, P = .06). Agreement was good between VE and DIA. It may be possible to use DIA or VE to measure cellularity in the appropriate clinical scenario. The limited sample size precludes similar determinations for MRI calculations. Further studies examining healthy donors are necessary before making definitive conclusions regarding age and cellularity. © 2017 John Wiley & Sons Ltd.

47 CFR 54.680 - Validity of electronic signatures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 3 2013-10-01 2013-10-01 false Validity of electronic signatures. 54.680... Validity of electronic signatures. (a) For the purposes of this subpart, an electronic signature (defined by the Electronic Signatures in Global and National Commerce Act, as an electronic sound, symbol, or...

47 CFR 54.419 - Validity of electronic signatures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 3 2013-10-01 2013-10-01 false Validity of electronic signatures. 54.419... electronic signatures. (a) For the purposes of this subpart, an electronic signature, defined by the Electronic Signatures in Global and National Commerce Act, as an electronic sound, symbol, or process...

47 CFR 54.419 - Validity of electronic signatures.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 3 2012-10-01 2012-10-01 false Validity of electronic signatures. 54.419... electronic signatures. (a) For the purposes of this subpart, an electronic signature, defined by the Electronic Signatures in Global and National Commerce Act, as an electronic sound, symbol, or process...

47 CFR 54.680 - Validity of electronic signatures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 3 2014-10-01 2014-10-01 false Validity of electronic signatures. 54.680... Validity of electronic signatures. (a) For the purposes of this subpart, an electronic signature (defined by the Electronic Signatures in Global and National Commerce Act, as an electronic sound, symbol, or...

47 CFR 54.419 - Validity of electronic signatures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 3 2014-10-01 2014-10-01 false Validity of electronic signatures. 54.419... electronic signatures. (a) For the purposes of this subpart, an electronic signature, defined by the Electronic Signatures in Global and National Commerce Act, as an electronic sound, symbol, or process...

Neural correlates of context-dependent feature conjunction learning in visual search tasks.

PubMed

Reavis, Eric A; Frank, Sebastian M; Greenlee, Mark W; Tse, Peter U

2016-06-01

Many perceptual learning experiments show that repeated exposure to a basic visual feature such as a specific orientation or spatial frequency can modify perception of that feature, and that those perceptual changes are associated with changes in neural tuning early in visual processing. Such perceptual learning effects thus exert a bottom-up influence on subsequent stimulus processing, independent of task-demands or endogenous influences (e.g., volitional attention). However, it is unclear whether such bottom-up changes in perception can occur as more complex stimuli such as conjunctions of visual features are learned. It is not known whether changes in the efficiency with which people learn to process feature conjunctions in a task (e.g., visual search) reflect true bottom-up perceptual learning versus top-down, task-related learning (e.g., learning better control of endogenous attention). Here we show that feature conjunction learning in visual search leads to bottom-up changes in stimulus processing. First, using fMRI, we demonstrate that conjunction learning in visual search has a distinct neural signature: an increase in target-evoked activity relative to distractor-evoked activity (i.e., a relative increase in target salience). Second, we demonstrate that after learning, this neural signature is still evident even when participants passively view learned stimuli while performing an unrelated, attention-demanding task. This suggests that conjunction learning results in altered bottom-up perceptual processing of the learned conjunction stimuli (i.e., a perceptual change independent of the task). We further show that the acquired change in target-evoked activity is contextually dependent on the presence of distractors, suggesting that search array Gestalts are learned. Hum Brain Mapp 37:2319-2330, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

40 CFR 263.25 - Electronic manifest signatures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Electronic manifest signatures. 263.25 Section 263.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES... Recordkeeping § 263.25 Electronic manifest signatures. (a) Electronic manifest signatures shall meet the...

21 CFR 11.200 - Electronic signature components and controls.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Electronic signature components and controls. 11... SERVICES GENERAL ELECTRONIC RECORDS; ELECTRONIC SIGNATURES Electronic Signatures § 11.200 Electronic signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1...

Seismic signature analysis for discrimination of people from animals

NASA Astrophysics Data System (ADS)

Damarla, Thyagaraju; Mehmood, Asif; Sabatier, James M.

2013-05-01

Cadence analysis has been the main focus for discriminating between the seismic signatures of people and animals. However, cadence analysis fails when multiple targets are generating the signatures. We analyze the mechanism of human walking and the signature generated by a human walker, and compare it with the signature generated by a quadruped. We develop Fourier-based analysis to differentiate the human signatures from the animal signatures. We extract a set of basis vectors to represent the human and animal signatures using non-negative matrix factorization, and use them to separate and classify both the targets. Grazing animals such as deer, cows, etc., often produce sporadic signals as they move around from patch to patch of grass and one must characterize them so as to differentiate their signatures from signatures generated by a horse steadily walking along a path. These differences in the signatures are used in developing a robust algorithm to distinguish the signatures of animals from humans. The algorithm is tested on real data collected in a remote area.

Modeling, materials, and metrics: the three-m approach to FCS signature solutions

NASA Astrophysics Data System (ADS)

Gonda, Teresa G.; Thomas, David J.; Namburu, Raju; Edwards, Timothy

2002-08-01

There is a push in the Army to develop lighter vehicles that can get to remote parts of the world quickly. This objective force is not some new vehicle, but a whole new way of fighting wars. The Future Combat System (FCS), as it is called, has an extremely aggressive timeline and must rely on modeling and simulation to aid in defining the goals, optimizing the design and materials, and testing the performance of the various FCS systems concepts. While virtual prototyping for vehicles (both military and commercial) has been around as a concept for well over a decade and its use is promoted heavily in tours and in boardrooms, the actual application of virtual protoyping is often limited and when successful has been confined to specific physical engineering areas such as weight, space, stress, mobility, and ergonomics. If FCS is to succeed in its acquisition schedule, virtual prototyping will have to be relied on heavily and its application expanded. Signature management is an example of an area that would benefit greatly from virtual prototyping tools. However, there are several obstacles to achieving this goal. To rigorously analyze a vehicle's IR and visual signatures extensively in several different environments over different weather and seasonal conditions could result millions of potentially unique signatures to evaluate. In addition, there is no real agreement on what evaluate means or even what value is used to represent signature; Delta T( degree(s)C), Probability of Detection? What the user really wants to know is: how do I make my system survivable? This paper attempts to describe and then bound the problem and describe how the Army is attempting to deal with some of these issues in a holistic manner using SMART (Simulation and Modeling for Acquisition, Requirements, and Training) principles.

Blended Learning in the Visual Communications Classroom: Student Reflections on a Multimedia Course

ERIC Educational Resources Information Center

George-Palilonis, Jennifer; Filak, Vincent

2009-01-01

Advances in digital technology and a rapidly evolving media landscape continue to dramatically change teaching and learning. Among these changes is the emergence of multimedia teaching and learning tools, online degree programs, and hybrid classes that blend traditional and digital content delivery. At the same time, visual communication programs…

Narrative in Young Children's Digital Art-Making

ERIC Educational Resources Information Center

Sakr, Mona; Connelly, Vince; Wild, Mary

2016-01-01

Digital technologies have material and social properties that have the potential to create new opportunities for children's expressive arts practices. The presence and development of oral narratives in young children's visual art-making on paper has been noted in previous research, but little is known about the narratives children create when they…

The Importance of Hydrological Signature and Its Recurring Dynamics

NASA Astrophysics Data System (ADS)

Wendi, D.; Marwan, N.; Merz, B.

2017-12-01

Temporal changes in hydrology are known to be challenging to detect and attribute due to multiple drivers that include complex processes that are non-stationary and highly variable. These drivers, such as human-induced climate change, natural climate variability, implementation of flood defense, river training, and land use change, could impact variably on space-time scales and influence or mask each other. Besides, data depicting these drivers are often not available. One conventional approach of analyzing the change is based on discrete points of magnitude (e.g. the frequency of recurring extreme discharge) and often linearly quantified and hence do not reveal the potential change in the hydrological process. Moreover, discharge series are often subject to measurement errors, such as rating curve error especially in the case of flood peaks where observation are derived through extrapolation. In this study, the system dynamics inferred from the hydrological signature (i.e. the shape of hydrograph) is being emphasized. One example is to see if certain flood dynamics (instead of flood peak) in the recent years, had also occurred in the past (or rather extraordinary), and if so what is its recurring rate and if there had been a shift in its occurrence in time or seasonality (e.g. earlier snow melt dominant flood). The utilization of hydrological signature here is extended beyond those of classical hydrology such as base flow index, recession and rising limb slope, and time to peak. It is in fact all these characteristics combined i.e. from the start until the end of the hydrograph. Recurrence plot is used as a method to quantify and visualize the recurring hydrological signature through its phase space trajectories, and usually in the order of dimension above 2. Such phase space trajectories are constructed by embedding the time series into a series of variables (i.e. number of dimension) corresponding to the time delay. Since the method is rather novel in

Mutational Signatures in Cancer (MuSiCa): a web application to implement mutational signatures analysis in cancer samples.

PubMed

Díaz-Gay, Marcos; Vila-Casadesús, Maria; Franch-Expósito, Sebastià; Hernández-Illán, Eva; Lozano, Juan José; Castellví-Bel, Sergi

2018-06-14

Mutational signatures have been proved as a valuable pattern in somatic genomics, mainly regarding cancer, with a potential application as a biomarker in clinical practice. Up to now, several bioinformatic packages to address this topic have been developed in different languages/platforms. MutationalPatterns has arisen as the most efficient tool for the comparison with the signatures currently reported in the Catalogue of Somatic Mutations in Cancer (COSMIC) database. However, the analysis of mutational signatures is nowadays restricted to a small community of bioinformatic experts. In this work we present Mutational Signatures in Cancer (MuSiCa), a new web tool based on MutationalPatterns and built using the Shiny framework in R language. By means of a simple interface suited to non-specialized researchers, it provides a comprehensive analysis of the somatic mutational status of the supplied cancer samples. It permits characterizing the profile and burden of mutations, as well as quantifying COSMIC-reported mutational signatures. It also allows classifying samples according to the above signature contributions. MuSiCa is a helpful web application to characterize mutational signatures in cancer samples. It is accessible online at http://bioinfo.ciberehd.org/GPtoCRC/en/tools.html and source code is freely available at https://github.com/marcos-diazg/musica .

Genome signature analysis of thermal virus metagenomes reveals Archaea and thermophilic signatures

PubMed Central

Pride, David T; Schoenfeld, Thomas

2008-01-01

Background Metagenomic analysis provides a rich source of biological information for otherwise intractable viral communities. However, study of viral metagenomes has been hampered by its nearly complete reliance on BLAST algorithms for identification of DNA sequences. We sought to develop algorithms for examination of viral metagenomes to identify the origin of sequences independent of BLAST algorithms. We chose viral metagenomes obtained from two hot springs, Bear Paw and Octopus, in Yellowstone National Park, as they represent simple microbial populations where comparatively large contigs were obtained. Thermal spring metagenomes have high proportions of sequences without significant Genbank homology, which has hampered identification of viruses and their linkage with hosts. To analyze each metagenome, we developed a method to classify DNA fragments using genome signature-based phylogenetic classification (GSPC), where metagenomic fragments are compared to a database of oligonucleotide signatures for all previously sequenced Bacteria, Archaea, and viruses. Results From both Bear Paw and Octopus hot springs, each assembled contig had more similarity to other metagenome contigs than to any sequenced microbial genome based on GSPC analysis, suggesting a genome signature common to each of these extreme environments. While viral metagenomes from Bear Paw and Octopus share some similarity, the genome signatures from each locale are largely unique. GSPC using a microbial database predicts most of the Octopus metagenome has archaeal signatures, while bacterial signatures predominate in Bear Paw; a finding consistent with those of Genbank BLAST. When using a viral database, the majority of the Octopus metagenome is predicted to belong to archaeal virus Families Globuloviridae and Fuselloviridae, while none of the Bear Paw metagenome is predicted to belong to archaeal viruses. As expected, when microbial and viral databases are combined, each of the Octopus and Bear Paw

48 CFR 204.101 - Contracting officer's signature.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Contracting officer's signature. 204.101 Section 204.101 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS... officer's signature. Follow the procedures at PGI 204.101 for signature of contract documents. [71 FR 9268...

Generation of signature databases with fast codes

NASA Astrophysics Data System (ADS)

Bradford, Robert A.; Woodling, Arthur E.; Brazzell, James S.

1990-09-01

Using the FASTSIG signature code to generate optical signature databases for the Ground-based Surveillance and Traking System (GSTS) Program has improved the efficiency of the database generation process. The goal of the current GSTS database is to provide standardized, threat representative target signatures that can easily be used for acquisition and trk studies, discrimination algorithm development, and system simulations. Large databases, with as many as eight interpolalion parameters, are required to maintain the fidelity demands of discrimination and to generalize their application to other strateg systems. As the need increases for quick availability of long wave infrared (LWIR) target signatures for an evolving design4o-threat, FASTSIG has become a database generation alternative to using the industry standard OptiCal Signatures Code (OSC). FASTSIG, developed in 1985 to meet the unique strategic systems demands imposed by the discrimination function, has the significant advantage of being a faster running signature code than the OSC, typically requiring two percent of the cpu time. It uses analytical approximations to model axisymmetric targets, with the fidelity required for discrimination analysis. Access of the signature database is accomplished through use of the waveband integration and interpolation software, INTEG and SIGNAT. This paper gives details of this procedure as well as sample interpolated signatures and also covers sample verification by comparison to the OSC, in order to establish the fidelity of the FASTSIG generated database.

Discrimination of fungal infections on grape berries via spectral signatures

NASA Astrophysics Data System (ADS)

Molitor, Daniel; Griesser, Michaela; Schütz, Erich; Khuen, Marie-Therese; Schefbeck, Christa; Ronellenfitsch, Franz Kai; Schlerf, Martin; Beyer, Marco; Schoedl-Hummel, Katharina; Anhalt, Ulrike; Forneck, Astrid

2016-04-01

The fungal pathogens Botrytis cinerea and Penicillium expansum are causing economic damages on grapevine worldwide. Especially the simultaneous occurrence of both often results in off-flavours highly threatening wine quality. For the classification of grape quality as well as for the determination of targeted enological treatments, the knowledge of the level of fungal attack is of highest interest. However, visual assessment and pathogen discrimination are cost-intensive. Consequently, a pilot laboratory study aimed at (i) detecting differences in spectral signatures between grape berry lots with different levels of infected berries (B. cinerea and/or P. expansum) and (ii) detecting links between spectral signatures and biochemical as well as quantitative molecular markers for fungal attack. To this end, defined percentages (infection levels) of table grape berries were inoculated with fungal spore suspensions. Spectral measurements were taken using a FieldSpec 3 Max spectroradiometer (ASD Inc., Boulder/Colorado, USA) in regular intervals after inoculation. In addition, fungal attack was determined enzymatically) and quantitatively (real-time PCR). In addition, gluconic acid concentrations (as a potential markers for fungal attack) were determined photometrically. Results indicate that based on spectral signatures, a discrimination of P. expansum and B. cinerea infections as well as of different B. cinerea infection levels is possible. Real-time PCR analyses, detecting DNA levels of both fungi, showed yet a low detection level. Whereas the gluconic acid concentrations turned out to be specific for the two fungi tested (B. cinerea vs. P. expansum) and thus may serve as a differentiating biochemical marker. Correlation analyses between spectral measurements and biological data (gluconic acid concentrations, fungi DNA) as well as further common field and laboratory trials are targeted.

Digital image analysis techniques for fiber and soil mixtures.

DOT National Transportation Integrated Search

1999-05-01

The objective of image processing is to visually enhance, quantify, and/or statistically evaluate some aspect of an image not readily apparent in its original form. Processed digital image data can be analyzed in numerous ways. In order to summarize ...

Digital Microdroplet Ejection Technology-Based Heterogeneous Objects Prototyping

PubMed Central

Yang, Jiquan; Feng, Chunmei; Yang, Jianfei; Zhu, Liya; Guo, Aiqing

2016-01-01

An integrate fabrication framework is presented to build heterogeneous objects (HEO) using digital microdroplets injecting technology and rapid prototyping. The heterogeneous materials part design and manufacturing method in structure and material was used to change the traditional process. The net node method was used for digital modeling that can configure multimaterials in time. The relationship of material, color, and jetting nozzle was built. The main important contributions are to combine the structure, material, and visualization in one process and give the digital model for manufacture. From the given model, it is concluded that the method is effective for HEO. Using microdroplet rapid prototyping and the model given in the paper HEO could be gotten basically. The model could be used in 3D biomanufacturing. PMID:26981110

Digital Microdroplet Ejection Technology-Based Heterogeneous Objects Prototyping.

PubMed

Li, Na; Yang, Jiquan; Feng, Chunmei; Yang, Jianfei; Zhu, Liya; Guo, Aiqing

2016-01-01

An integrate fabrication framework is presented to build heterogeneous objects (HEO) using digital microdroplets injecting technology and rapid prototyping. The heterogeneous materials part design and manufacturing method in structure and material was used to change the traditional process. The net node method was used for digital modeling that can configure multimaterials in time. The relationship of material, color, and jetting nozzle was built. The main important contributions are to combine the structure, material, and visualization in one process and give the digital model for manufacture. From the given model, it is concluded that the method is effective for HEO. Using microdroplet rapid prototyping and the model given in the paper HEO could be gotten basically. The model could be used in 3D biomanufacturing.

In Situ 3D Monitoring of Geometric Signatures in the Powder-Bed-Fusion Additive Manufacturing Process via Vision Sensing Methods

PubMed Central

Li, Zhongwei; Liu, Xingjian; Wen, Shifeng; He, Piyao; Zhong, Kai; Wei, Qingsong; Shi, Yusheng; Liu, Sheng

2018-01-01

Lack of monitoring of the in situ process signatures is one of the challenges that has been restricting the improvement of Powder-Bed-Fusion Additive Manufacturing (PBF AM). Among various process signatures, the monitoring of the geometric signatures is of high importance. This paper presents the use of vision sensing methods as a non-destructive in situ 3D measurement technique to monitor two main categories of geometric signatures: 3D surface topography and 3D contour data of the fusion area. To increase the efficiency and accuracy, an enhanced phase measuring profilometry (EPMP) is proposed to monitor the 3D surface topography of the powder bed and the fusion area reliably and rapidly. A slice model assisted contour detection method is developed to extract the contours of fusion area. The performance of the techniques is demonstrated with some selected measurements. Experimental results indicate that the proposed method can reveal irregularities caused by various defects and inspect the contour accuracy and surface quality. It holds the potential to be a powerful in situ 3D monitoring tool for manufacturing process optimization, close-loop control, and data visualization. PMID:29649171

Can specific transcriptional regulators assemble a universal cancer signature?

NASA Astrophysics Data System (ADS)

Roy, Janine; Isik, Zerrin; Pilarsky, Christian; Schroeder, Michael

2013-10-01

Recently, there is a lot of interest in using biomarker signatures derived from gene expression data to predict cancer progression. We assembled signatures of 25 published datasets covering 13 types of cancers. How do these signatures compare with each other? On one hand signatures answering the same biological question should overlap, whereas signatures predicting different cancer types should differ. On the other hand, there could also be a Universal Cancer Signature that is predictive independently of the cancer type. Initially, we generate signatures for all datasets using classical approaches such as t-test and fold change and then, we explore signatures resulting from a network-based method, that applies the random surfer model of Google's PageRank algorithm. We show that the signatures as published by the authors and the signatures generated with classical methods do not overlap - not even for the same cancer type - whereas the network-based signatures strongly overlap. Selecting 10 out of 37 universal cancer genes gives the optimal prediction for all cancers thus taking a first step towards a Universal Cancer Signature. We furthermore analyze and discuss the involved genes in terms of the Hallmarks of cancer and in particular single out SP1, JUN/FOS and NFKB1 and examine their specific role in cancer progression.

25 CFR 82.7 - Notarization of petition signatures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Notarization of petition signatures. 82.7 Section 82.7... signatures. (a) Signatures to a petition must be authenticated in one of the following ways: (1) Through having each signer subscribe or acknowledge his/her signature before a notary public; (2) Through having...

Penn State's Visual Image User Study

ERIC Educational Resources Information Center

Pisciotta, Henry A.; Dooris, Michael J.; Frost, James; Halm, Michael

2005-01-01

The Visual Image User Study (VIUS), an extensive needs assessment project at Penn State University, describes academic users of pictures and their perceptions. These findings outline the potential market for digital images and list the likely determinates of whether or not a system will be used. They also explain some key user requirements for…

Linguistic Layering: Social Language Development in the Context of Multimodal Design and Digital Technologies

ERIC Educational Resources Information Center

Domingo, Myrrh

2012-01-01

In our contemporary society, digital texts circulate more readily and extend beyond page-bound formats to include interactive representations such as online newsprint with hyperlinks to audio and video files. This is to say that multimodality combined with digital technologies extends grammar to include voice, visual, and music, among other modes…

Built-in-test by signature inspection (bitsi)

DOEpatents

Bergeson, Gary C.; Morneau, Richard A.

1991-01-01

A system and method for fault detection for electronic circuits. A stimulus generator sends a signal to the input of the circuit under test. Signature inspection logic compares the resultant signal from test nodes on the circuit to an expected signal. If the signals do not match, the signature inspection logic sends a signal to the control logic for indication of fault detection in the circuit. A data input multiplexer between the test nodes of the circuit under test and the signature inspection logic can provide for identification of the specific node at fault by the signature inspection logic. Control logic responsive to the signature inspection logic conveys information about fault detection for use in determining the condition of the circuit. When used in conjunction with a system test controller, the built-in test by signature inspection system and method can be used to poll a plurality of circuits automatically and continuous for faults and record the results of such polling in the system test controller.

Intrusion detection using secure signatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, Trent Darnel; Haile, Jedediah

A method and device for intrusion detection using secure signatures comprising capturing network data. A search hash value, value employing at least one one-way function, is generated from the captured network data using a first hash function. The presence of a search hash value match in a secure signature table comprising search hash values and an encrypted rule is determined. After determining a search hash value match, a decryption key is generated from the captured network data using a second hash function, a hash function different form the first hash function. One or more of the encrypted rules of themore » secure signatures table having a hash value equal to the generated search hash value are then decrypted using the generated decryption key. The one or more decrypted secure signature rules are then processed for a match and one or more user notifications are deployed if a match is identified.« less

Current signature sensor

NASA Technical Reports Server (NTRS)

Perotti, Jose M. (Inventor); Lucena, Angel (Inventor); Ihlefeld, Curtis (Inventor); Burns, Bradley (Inventor); Bassignani, Karin E. (Inventor)

2005-01-01

A solenoid health monitoring system uses a signal conditioner and controller assembly in one embodiment that includes analog circuitry and a DSP controller. The analog circuitry provides signal conditioning to the low-level raw signal coming from a signal acquisition assembly. Software running in a DSP analyzes the incoming data (recorded current signature) and determines the state of the solenoid whether it is energized, de-energized, or in a transitioning state. In one embodiment, the software identifies key features in the current signature during the transition phase and is able to determine the health of the solenoid.

17 CFR 230.471 - Signatures to amendments.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Signatures to amendments. 230... RULES AND REGULATIONS, SECURITIES ACT OF 1933 Amendments; Withdrawals § 230.471 Signatures to amendments... signed, such document shall be manually signed, or signed using either typed signatures or duplicated or...

31 CFR 321.19 - Certification of signatures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Certification of signatures. 321.19... From Erroneous Payments § 321.19 Certification of signatures. The regulations in this subpart shall, to... signatures by an officer or designated employee of any financial institution authorized to certify requests...

40 CFR 262.25 - Electronic manifest signatures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Electronic manifest signatures. 262.25... (CONTINUED) STANDARDS APPLICABLE TO GENERATORS OF HAZARDOUS WASTE The Manifest § 262.25 Electronic manifest signatures. Electronic signature methods for the e-Manifest system shall: (a) Be a legally valid and...

17 CFR 201.65 - Identity and signature.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Identity and signature. 201.65... of 1934 § 201.65 Identity and signature. Applications pursuant to this subpart may omit the identity, mailing address, and signature of the applicant; provided, that such identity, mailing address and...

Evolutionary analysis of vision genes identifies potential drivers of visual differences between giraffe and okapi

PubMed Central

Agaba, Morris; Cavener, Douglas R.

2017-01-01

Background The capacity of visually oriented species to perceive and respond to visual signal is integral to their evolutionary success. Giraffes are closely related to okapi, but the two species have broad range of phenotypic differences including their visual capacities. Vision studies rank giraffe’s visual acuity higher than all other artiodactyls despite sharing similar vision ecological determinants with many of them. The extent to which the giraffe’s unique visual capacity and its difference with okapi is reflected by changes in their vision genes is not understood. Methods The recent availability of giraffe and okapi genomes provided opportunity to identify giraffe and okapi vision genes. Multiple strategies were employed to identify thirty-six candidate mammalian vision genes in giraffe and okapi genomes. Quantification of selection pressure was performed by a combination of branch-site tests of positive selection and clade models of selection divergence through comparing giraffe and okapi vision genes and orthologous sequences from other mammals. Results Signatures of selection were identified in key genes that could potentially underlie giraffe and okapi visual adaptations. Importantly, some genes that contribute to optical transparency of the eye and those that are critical in light signaling pathway were found to show signatures of adaptive evolution or selection divergence. Comparison between giraffe and other ruminants identifies significant selection divergence in CRYAA and OPN1LW. Significant selection divergence was identified in SAG while positive selection was detected in LUM when okapi is compared with ruminants and other mammals. Sequence analysis of OPN1LW showed that at least one of the sites known to affect spectral sensitivity of the red pigment is uniquely divergent between giraffe and other ruminants. Discussion By taking a systemic approach to gene function in vision, the results provide the first molecular clues associated with

Evolutionary analysis of vision genes identifies potential drivers of visual differences between giraffe and okapi.

PubMed

Ishengoma, Edson; Agaba, Morris; Cavener, Douglas R

2017-01-01

The capacity of visually oriented species to perceive and respond to visual signal is integral to their evolutionary success. Giraffes are closely related to okapi, but the two species have broad range of phenotypic differences including their visual capacities. Vision studies rank giraffe's visual acuity higher than all other artiodactyls despite sharing similar vision ecological determinants with many of them. The extent to which the giraffe's unique visual capacity and its difference with okapi is reflected by changes in their vision genes is not understood. The recent availability of giraffe and okapi genomes provided opportunity to identify giraffe and okapi vision genes. Multiple strategies were employed to identify thirty-six candidate mammalian vision genes in giraffe and okapi genomes. Quantification of selection pressure was performed by a combination of branch-site tests of positive selection and clade models of selection divergence through comparing giraffe and okapi vision genes and orthologous sequences from other mammals. Signatures of selection were identified in key genes that could potentially underlie giraffe and okapi visual adaptations. Importantly, some genes that contribute to optical transparency of the eye and those that are critical in light signaling pathway were found to show signatures of adaptive evolution or selection divergence. Comparison between giraffe and other ruminants identifies significant selection divergence in CRYAA and OPN1LW . Significant selection divergence was identified in SAG while positive selection was detected in LUM when okapi is compared with ruminants and other mammals. Sequence analysis of OPN1LW showed that at least one of the sites known to affect spectral sensitivity of the red pigment is uniquely divergent between giraffe and other ruminants. By taking a systemic approach to gene function in vision, the results provide the first molecular clues associated with giraffe and okapi vision adaptations. At

ESL and Digital Video Integration: Case Studies

ERIC Educational Resources Information Center

Li, J., Ed.; Gromik, N., Ed.; Edwards, N., Ed.

2013-01-01

It should come as no surprise that digital video technology is of particular interest to English language learners; students are drawn to its visual appeal and vibrant creative potential. The seven original case studies in this book demonstrate how video can be an effective and powerful tool to create fluid, fun, interactive, and collaborative…

Twenty-four signature genes predict the prognosis of oral squamous cell carcinoma with high accuracy and repeatability

PubMed Central

Gao, Jianyong; Tian, Gang; Han, Xu; Zhu, Qiang

2018-01-01

Oral squamous cell carcinoma (OSCC) is the sixth most common type cancer worldwide, with poor prognosis. The present study aimed to identify gene signatures that could classify OSCC and predict prognosis in different stages. A training data set (GSE41613) and two validation data sets (GSE42743 and GSE26549) were acquired from the online Gene Expression Omnibus database. In the training data set, patients were classified based on the tumor-node-metastasis staging system, and subsequently grouped into low stage (L) or high stage (H). Signature genes between L and H stages were selected by disparity index analysis, and classification was performed by the expression of these signature genes. The established classification was compared with the L and H classification, and fivefold cross validation was used to evaluate the stability. Enrichment analysis for the signature genes was implemented by the Database for Annotation, Visualization and Integration Discovery. Two validation data sets were used to determine the precise of classification. Survival analysis was conducted followed each classification using the package ‘survival’ in R software. A set of 24 signature genes was identified based on the classification model with the Fi value of 0.47, which was used to distinguish OSCC samples in two different stages. Overall survival of patients in the H stage was higher than those in the L stage. Signature genes were primarily enriched in ‘ether lipid metabolism’ pathway and biological processes such as ‘positive regulation of adaptive immune response’ and ‘apoptotic cell clearance’. The results provided a novel 24-gene set that may be used as biomarkers to predict OSCC prognosis with high accuracy, which may be used to determine an appropriate treatment program for patients with OSCC in addition to the traditional evaluation index. PMID:29257303

15 CFR 908.16 - Signature.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Signature. 908.16 Section 908.16 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) NATIONAL OCEANIC... SUBMITTING REPORTS ON WEATHER MODIFICATION ACTIVITIES § 908.16 Signature. All reports filed with the National...

Quantifying and Mapping the Digital Divide from an Internet Point of View

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cottrell, R.Les; /SLAC; Khan, Shahryar

2008-09-18

Quantitative knowledge of the magnitude, extent and trends of the Digital Divide are critical to understand and identify the regions most in need of help, to make rational decisions on how to address the problems and to make cases for executives, funding agencies and politicians. We report on a project (PingER) to measure the Digital Divide from the point of view of Internet performance. The PingER project has been measuring Internet performance since 1995 and with the increased emphasis on measuring and tracking the Digital Divide, it now covers over 700 hosts in over 150 countries that between them containmore » over 99% of the world's Internet connected population. In this paper we will describe the how PingER works, it deployment, the data analysis, and presentation. We also introduce a new PingER visualization tool (ViPER) that provides a more appealing interactive visualization of the PingER data and also works on mobile PDAs. We will also show results from PingER that illustrate the magnitude, extent and trends for the Digital Divide, and also compare PingER results with some human development and technology indices.« less

Neural signatures of co-occurring reading and mathematical difficulties.

PubMed

Skeide, Michael A; Evans, Tanya M; Mei, Edward Z; Abrams, Daniel A; Menon, Vinod

2018-06-19

Impaired abilities in multiple domains is common in children with learning difficulties. Co-occurrence of low reading and mathematical abilities (LRLM) appears in almost every second child with learning difficulties. However, little is known regarding the neural bases of this combination. Leveraging a unique and tightly controlled sample including children with LRLM, isolated low reading ability (LR), and isolated low mathematical ability (LM), we uncover a distinct neural signature in children with co-occurring low reading and mathematical abilities differentiable from LR and LM. Specifically, we show that LRLM is neuroanatomically distinct from both LR and LM based on reduced cortical folding of the right parahippocampal gyrus, a medial temporal lobe region implicated in visual associative learning. LRLM children were further distinguished from LR and LM by patterns of intrinsic functional connectivity between parahippocampal gyrus and brain circuitry underlying reading and numerical quantity processing. Our results critically inform cognitive and neural models of LRLM by implicating aberrations in both domain-specific and domain-general brain regions involved in reading and mathematics. More generally, our results provide the first evidence for distinct multimodal neural signatures associated with LRLM, and suggest that this population displays an independent phenotype of learning difficulty that cannot be explained simply as a combination of isolated low reading and mathematical abilities. © 2018 John Wiley & Sons Ltd.

A color-communication scheme for digital imagery

USGS Publications Warehouse

Acosta, Alex

1987-01-01

Color pictures generated from digital images are frequently used by geologists, foresters, range managers, and others. These color products are preferred over black and white pictures because the human eye is more sensitive to color differences than to various shades of gray. Color discrimination is a function of perception, and therefore colors in these color composites are generally described subjectively, which can lead to ambiguous color communication. Numerous color-coordinate systems are available that quantitively relate digital triplets representing amounts of red, free, and blue to the parameters of hue, saturation, and intensity perceived by the eye. Most of these systems implement a complex transformation of the primary colors to a color space that is hard to visualize, thus making it difficult to relate digital triplets to perception parameters. This paper presents a color-communcation scheme that relates colors on a color triangle to corresponding values of "hue" (H), "saturation" (S), and chromaticity coordinates (x,y,z). The scheme simplifies the relation between red, green, and blue (RGB) digital triplets and the color generated by these triplets. Some examples of the use of the color-communication scheme in digital image processing are presented.

29 CFR 102.116 - Signature of orders.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 2 2010-07-01 2010-07-01 false Signature of orders. 102.116 Section 102.116 Labor Regulations Relating to Labor NATIONAL LABOR RELATIONS BOARD RULES AND REGULATIONS, SERIES 8 Certification and Signature of Documents § 102.116 Signature of orders. The executive secretary or the associate executive...

ECDSA B-233 with Precomputation 1.0 Beta Version

DOE Office of Scientific and Technical Information (OSTI.GOV)

Draelos, Timothy; Schroeppel, Richard; Schoeneman, Barry

2009-12-11

This software, written in C, performs two functions: 1) the generation of digital signatures using ECDSA with the B-233 curve and a table of precomputed values, and 2) the generation and encryption of a table of precomputed values to support the generation of many digital signatures. The computationally expensive operations of ECDSA signature generation are precomputed, stored in a table, and protected with AES encryption. This allows digital signatures to be generated in low-power, computationally-constrained environments, such as are often found in non-proliferation monitoring applications. The encrypted, precomputed table and digital signature generation software are used to provide public keymore » data authentication for sensor data. When digital data is presented for signing, a set of values from the table is decrypted and used to generate an ECDSA digital signatureThis software, written in C, performs two functions: 1) the generation of digital signatures using ECDSA with the B-233 curve and a table of precomputed values, and 2) the generation and encryption of a table of precomputed values to support the generation of many digital signatures. The computationally expensive operations of ECDSA signature generation are precomputed, stored in a table, and protected with AES encryption. This allows digital signatures to be generated in low-power, computationally-constrained environments, such as are often found in non-proliferation monitoring applications. The encrypted, precomputed table and digital signature generation software are used to provide public key data authentication for sensor data. When digital data is presented for signing, a set of values from the table is decrypted and used to generate an ECDSA digital signature« less

The steady-state visual evoked potential in vision research: A review

PubMed Central

Norcia, Anthony M.; Appelbaum, L. Gregory; Ales, Justin M.; Cottereau, Benoit R.; Rossion, Bruno

2015-01-01

Periodic visual stimulation and analysis of the resulting steady-state visual evoked potentials were first introduced over 80 years ago as a means to study visual sensation and perception. From the first single-channel recording of responses to modulated light to the present use of sophisticated digital displays composed of complex visual stimuli and high-density recording arrays, steady-state methods have been applied in a broad range of scientific and applied settings.The purpose of this article is to describe the fundamental stimulation paradigms for steady-state visual evoked potentials and to illustrate these principles through research findings across a range of applications in vision science. PMID:26024451