WorldWideScience

Sample records for level-3 browse images

  1. Improved Software to Browse the Serial Medical Images for Learning.

    Science.gov (United States)

    Kwon, Koojoo; Chung, Min Suk; Park, Jin Seo; Shin, Byeong Seok; Chung, Beom Sun

    2017-07-01

    The thousands of serial images used for medical pedagogy cannot be included in a printed book; they also cannot be efficiently handled by ordinary image viewer software. The purpose of this study was to provide browsing software to grasp serial medical images efficiently. The primary function of the newly programmed software was to select images using 3 types of interfaces: buttons or a horizontal scroll bar, a vertical scroll bar, and a checkbox. The secondary function was to show the names of the structures that had been outlined on the images. To confirm the functions of the software, 3 different types of image data of cadavers (sectioned and outlined images, volume models of the stomach, and photos of the dissected knees) were inputted. The browsing software was downloadable for free from the homepage (anatomy.co.kr) and available off-line. The data sets provided could be replaced by any developers for their educational achievements. We anticipate that the software will contribute to medical education by allowing users to browse a variety of images. © 2017 The Korean Academy of Medical Sciences.

  2. Development of 3D browsing and interactive web system

    Science.gov (United States)

    Shi, Xiaonan; Fu, Jian; Jin, Chaolin

    2017-09-01

    In the current market, users need to download specific software or plug-ins to browse the 3D model, and browsing the system may be unstable, and it cannot be 3D model interaction issues In order to solve this problem, this paper presents a solution to the interactive browsing of the model in the server-side parsing model, and when the system is applied, the user only needs to input the system URL and upload the 3D model file to operate the browsing The server real-time parsing 3D model, the interactive response speed, these completely follows the user to walk the minimalist idea, and solves the current market block 3D content development question.

  3. Knowledge-based image data management - An expert front-end for the BROWSE facility

    Science.gov (United States)

    Stoms, David M.; Star, Jeffrey L.; Estes, John E.

    1988-01-01

    An intelligent user interface being added to the NASA-sponsored BROWSE testbed facility is described. BROWSE is a prototype system designed to explore issues involved in locating image data in distributed archives and displaying low-resolution versions of that imagery at a local terminal. For prototyping, the initial application is the remote sensing of forest and range land.

  4. Web tools for large-scale 3D biological images and atlases

    Directory of Open Access Journals (Sweden)

    Husz Zsolt L

    2012-06-01

    Full Text Available Abstract Background Large-scale volumetric biomedical image data of three or more dimensions are a significant challenge for distributed browsing and visualisation. Many images now exceed 10GB which for most users is too large to handle in terms of computer RAM and network bandwidth. This is aggravated when users need to access tens or hundreds of such images from an archive. Here we solve the problem for 2D section views through archive data delivering compressed tiled images enabling users to browse through very-large volume data in the context of a standard web-browser. The system provides an interactive visualisation for grey-level and colour 3D images including multiple image layers and spatial-data overlay. Results The standard Internet Imaging Protocol (IIP has been extended to enable arbitrary 2D sectioning of 3D data as well a multi-layered images and indexed overlays. The extended protocol is termed IIP3D and we have implemented a matching server to deliver the protocol and a series of Ajax/Javascript client codes that will run in an Internet browser. We have tested the server software on a low-cost linux-based server for image volumes up to 135GB and 64 simultaneous users. The section views are delivered with response times independent of scale and orientation. The exemplar client provided multi-layer image views with user-controlled colour-filtering and overlays. Conclusions Interactive browsing of arbitrary sections through large biomedical-image volumes is made possible by use of an extended internet protocol and efficient server-based image tiling. The tools open the possibility of enabling fast access to large image archives without the requirement of whole image download and client computers with very large memory configurations. The system was demonstrated using a range of medical and biomedical image data extending up to 135GB for a single image volume.

  5. Savanna browse production. 2: Prediction | Penderis | African ...

    African Journals Online (AJOL)

    Our study was initiated with the aim of modelling browse production rates of key savanna tree species in the northern Zululand region of KwaZulu-Natal, with the assumption that browse production equates to utilised browse biomass. Predictive models for the production of browse, at different game feeding levels, ...

  6. WeCurate: Designing for synchronised browsing and social negotiation

    OpenAIRE

    Hazelden, Katina; Yee-King, Matthew; d'Inverno, Mark; Confalonieri, Roberto; De Jonge, Dave; Amgoud, Leila; Osman, Nardine; Prade, Henri; Sierra, Carles

    2012-01-01

    WeCurate is a shared image browser for collaboratively curating a virtual exhibition from a cultural image archive. This paper is concerned with the evaluation and iteration of a prototype UI (User Interface) design to enable this community image browsing. In WeCurate, several remote users work together with autonomic agents to browse the archive and to select, through negotiation and voting, a set of images which are of the greatest interest to the group. The UI allows users to synchronize v...

  7. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 683 ... Issue, Title. Vol 54, No 1 (2006), Bovine tuberculosis survey in urban and peri urban dairy farms in coastal humid region of Tanga, Tanzania, Abstract. ES Swai, G Shirima, S Bwanga, W Moshy. Vol 60, No 3 (2012), Browsing capacity and nutritive value of indigenous browses in a tropical Coastal ...

  8. Mobile web browsing using the cloud

    CERN Document Server

    Zhao, Bo; Cao, Guohong

    2013-01-01

    This brief surveys existing techniques to address the problem of long delays and high power consumption for web browsing on smartphones, which can be due to the local computational limitation at the smartphone (e.g., running java scripts or flash objects) level. To address this issue, an architecture called Virtual-Machine based Proxy (VMP) is introduced, shifting the computing from smartphones to the VMP which may reside in the cloud. Mobile Web Browsing Using the Cloud illustrates the feasibility of deploying the proposed VMP system in 3G networks through a prototype using Xen virtual machin

  9. Android and iPhone Apps for Viewing Browse Plots from the Magnetospheric Imaging Instrument (MIMI) on Cassin

    Science.gov (United States)

    Vandegriff, J. D.; Kusterer, M. B.; Byun, S.; Steele, R. J.; Mitchell, D. G.

    2017-12-01

    We present a new mobile app for Android and an existing app for iPhone, both capable of viewing the numerous browse plots available for data collected by the MIMI suite on NASA's Cassini spacecraft. Both apps allow convenient mobile access to pre-made plots of data from various instruments on the suite, including daily, and monthly plots of particle intensities (line plots and spectrograms) from LEMMS, CHEMS and INCA. Also, the apps can show short movies made from sequences of INCA neutral atom images. Browsing the plots or movies is as simple as swiping to the left or right, and the app hides all access details needed to finding the images. Note that the app requires a data connection, since it locates and downloads the plot files live from various instrument team servers. We will demonstrate the current versions of both apps, which are available in Apple's App Store and the Google Play Store.

  10. Helioviewer.org: Browsing Very Large Image Archives Online Using JPEG 2000

    Science.gov (United States)

    Hughitt, V. K.; Ireland, J.; Mueller, D.; Dimitoglou, G.; Garcia Ortiz, J.; Schmidt, L.; Wamsler, B.; Beck, J.; Alexanderian, A.; Fleck, B.

    2009-12-01

    As the amount of solar data available to scientists continues to increase at faster and faster rates, it is important that there exist simple tools for navigating this data quickly with a minimal amount of effort. By combining heterogeneous solar physics datatypes such as full-disk images and coronagraphs, along with feature and event information, Helioviewer offers a simple and intuitive way to browse multiple datasets simultaneously. Images are stored in a repository using the JPEG 2000 format and tiled dynamically upon a client's request. By tiling images and serving only the portions of the image requested, it is possible for the client to work with very large images without having to fetch all of the data at once. In addition to a focus on intercommunication with other virtual observatories and browsers (VSO, HEK, etc), Helioviewer will offer a number of externally-available application programming interfaces (APIs) to enable easy third party use, adoption and extension. Recent efforts have resulted in increased performance, dynamic movie generation, and improved support for mobile web browsers. Future functionality will include: support for additional data-sources including RHESSI, SDO, STEREO, and TRACE, a navigable timeline of recorded solar events, social annotation, and basic client-side image processing.

  11. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 414 ... Journal Home > Advanced Search > Browse Title Index. Log in or ... of an algebraic function for the permutation of truth table columns, Abstract ... appraisal and productivity levels in selected Nigerian universities, Abstract.

  12. Exploring the Concept of Browsing from the Literature Analysis

    Directory of Open Access Journals (Sweden)

    Shan-Ju L. Chang

    1997-12-01

    Full Text Available Browsing as a concept and an activity appears to be a fundamental part of human information behavior, which takes place in diverse contexts in our daily life. At the theoretical level, research on browsing can extend and develop theories of human information behavior. Practically, there could be suggestions for better organization and representation of information and material displayed as well as for effective information seeking and retrieval. This thesis attempts to explore the browsing phenomenon as it appears in the library and information science literature and end-user computing literature. Topics included for discussion are the definitions of the browsing concept, potential consequences, topology and influential factors of browsing as being identified from the literature analysis.[Article content in Chinese

  13. Video Browsing on Handheld Devices

    Science.gov (United States)

    Hürst, Wolfgang

    Recent improvements in processing power, storage space, and video codec development enable users now to playback video on their handheld devices in a reasonable quality. However, given the form factor restrictions of such a mobile device, screen size still remains a natural limit and - as the term "handheld" implies - always will be a critical resource. This is not only true for video but any data that is processed on such devices. For this reason, developers have come up with new and innovative ways to deal with large documents in such limited scenarios. For example, if you look at the iPhone, innovative techniques such as flicking have been introduced to skim large lists of text (e.g. hundreds of entries in your music collection). Automatically adapting the zoom level to, for example, the width of table cells when double tapping on the screen enables reasonable browsing of web pages that have originally been designed for large, desktop PC sized screens. A multi touch interface allows you to easily zoom in and out of large text documents and images using two fingers. In the next section, we will illustrate that advanced techniques to browse large video files have been developed in the past years, as well. However, if you look at state-of-the-art video players on mobile devices, normally just simple, VCR like controls are supported (at least at the time of this writing) that only allow users to just start, stop, and pause video playback. If supported at all, browsing and navigation functionality is often restricted to simple skipping of chapters via two single buttons for backward and forward navigation and a small and thus not very sensitive timeline slider.

  14. African Journals Online: Browse by Country

    African Journals Online (AJOL)

    African Journals Online: Browse by Country. Home > African Journals Online: Browse by Country. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Browse By Category · Browse Alphabetically · Browse By Country · List All Titles · Free to read Titles This Journal is ...

  15. Browse Title Index

    African Journals Online (AJOL)

    Items 251 - 300 of 1260 ... Journal Home > Advanced Search > Browse Title Index ... Consumption of ammonia-nitrogen by aob in immobilized batch culture, Abstract PDF .... Vol 9, No 3S (2017): Special Issue, Design an automatic temperature ...

  16. The SSABLE system - Automated archive, catalog, browse and distribution of satellite data in near-real time

    Science.gov (United States)

    Simpson, James J.; Harkins, Daniel N.

    1993-01-01

    Historically, locating and browsing satellite data has been a cumbersome and expensive process. This has impeded the efficient and effective use of satellite data in the geosciences. SSABLE is a new interactive tool for the archive, browse, order, and distribution of satellite date based upon X Window, high bandwidth networks, and digital image rendering techniques. SSABLE provides for automatically constructing relational database queries to archived image datasets based on time, data, geographical location, and other selection criteria. SSABLE also provides a visual representation of the selected archived data for viewing on the user's X terminal. SSABLE is a near real-time system; for example, data are added to SSABLE's database within 10 min after capture. SSABLE is network and machine independent; it will run identically on any machine which satisfies the following three requirements: 1) has a bitmapped display (monochrome or greater); 2) is running the X Window system; and 3) is on a network directly reachable by the SSABLE system. SSABLE has been evaluated at over 100 international sites. Network response time in the United States and Canada varies between 4 and 7 s for browse image updates; reported transmission times to Europe and Australia typically are 20-25 s.

  17. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 1117 ... Journal Home > Advanced Search > Browse Title Index ... Vol 13, No 3 (2007):, an edu-ethical perspecitve on the nature of truth: case studies in elite ... 2009: September: Supplement, An empirical study of university ...

  18. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 1732 ... Journal Home > Advanced Search > Browse Title Index ... Vol 10, No 3 (2007), An Audit Of Perioperative Cardiac Arrest At ... Vol 11, No 4 (2008), An Audit Of Rejected Repeated X-ray Films As A Quality Assurance ...

  19. Browse Title Index

    African Journals Online (AJOL)

    Items 751 - 800 of 846 ... Journal Home > Advanced Search > Browse Title Index ... Vol 9, No 3S (2017): Special Issue, The effect of torrefaction on oil palm ... core competency skills of IRBM tax auditors towards their performance, Abstract PDF ... of exchange rates behavior in Malaysia by using NATREX model, Abstract PDF.

  20. Cooperative Mobile Web Browsing

    DEFF Research Database (Denmark)

    Perrucci, GP; Fitzek, FHP; Zhang, Qi

    2009-01-01

    This paper advocates a novel approach for mobile web browsing based on cooperation among wireless devices within close proximity operating in a cellular environment. In the actual state of the art, mobile phones can access the web using different cellular technologies. However, the supported data......-range links can then be used for cooperative mobile web browsing. By implementing the cooperative web browsing on commercial mobile phones, it will be shown that better performance is achieved in terms of increased data rate and therefore reduced access times, resulting in a significantly enhanced web...

  1. Semantic Identification Attacks on Web Browsing

    OpenAIRE

    Guha, Neel

    2016-01-01

    We introduce a Semantic Identification Attack, in which an adversary uses semantic signals about the pages visited in one browsing session to identify other browsing sessions launched by the same user. This attack allows an adver- sary to determine if two browsing sessions originate from the same user regardless of any measures taken by the user to disguise their browser or network. We use the MSNBC Anonymous Browsing data set, which contains a large set of user visits (labeled by category) t...

  2. Using Psychophysiological Sensors to Assess Mental Workload During Web Browsing.

    Science.gov (United States)

    Jimenez-Molina, Angel; Retamal, Cristian; Lira, Hernan

    2018-02-03

    Knowledge of the mental workload induced by a Web page is essential for improving users' browsing experience. However, continuously assessing the mental workload during a browsing task is challenging. To address this issue, this paper leverages the correlation between stimuli and physiological responses, which are measured with high-frequency, non-invasive psychophysiological sensors during very short span windows. An experiment was conducted to identify levels of mental workload through the analysis of pupil dilation measured by an eye-tracking sensor. In addition, a method was developed to classify mental workload by appropriately combining different signals (electrodermal activity (EDA), electrocardiogram, photoplethysmo-graphy (PPG), electroencephalogram (EEG), temperature and pupil dilation) obtained with non-invasive psychophysiological sensors. The results show that the Web browsing task involves four levels of mental workload. Also, by combining all the sensors, the efficiency of the classification reaches 93.7%.

  3. The Helioviewer Project: Browsing, Visualizing and Accessing Petabytes of Solar Data

    Science.gov (United States)

    Mueller, Daniel; Hughitt, V. K.; Langenberg, M.; Ireland, J.; Pagel, S.; Schmidt, L.; Garcia Ortiz, J. P.; Dimitoglou, G.; Fleck, B.

    2010-05-01

    After its successful launch, NASA's Solar Dynamics Observatory (SDO) will soon return more than 1 Terabyte worth of images per day. This unprecedented torrent of data will pose an entirely new set of challenges with respect to data access, data browsing and searching for interesting data while avoiding the proverbial search for "a needle in a haystack". In order to fully exploit SDO's wealth of data and connect it to data from other solar missions like SOHO, scientists need to be able to interactively browse and visualize many different data products spanning a large range of physical length and time scales. So far, all tools available to the scientific community either require downloading all potentially relevant data sets beforehand in their entirety or provide only movies with a fixed resolution and cadence. The Helioviewer project offers a solution to these challenges by providing a suite of tools that are based on the new JPEG 2000 compression standard and enable scientists and the general public alike to intuitively browse visualize and access petabytes of image data remotely: - JHelioviewer, a cross-platform application that offers movie streaming and real-time processing using the JPEG 2000 Interactive Protocol (JPIP) and OpenGL, as well as feature/event overlays. - helioviewer.org, a web-based image and feature/event browser. - Server-side services to stream movies of arbitrary spatial and temporal resolution in a region-of-interest and quality-progressive form, a JPEG 2000 image database and a feature/event server. All the services can be accessed through well-documented interfaces (APIs). - Code to convert images into JPEG 2000 format. This presentation will give an overview of the Helioviewer Project, illustrate new features and highlight the advantages of JPEG 2000 as a data format for solar physics that has the potential to revolutionize the way high-resolution image data are disseminated and analyzed.

  4. A Web Service for File-Level Access to Disk Images

    Directory of Open Access Journals (Sweden)

    Sunitha Misra

    2014-07-01

    Full Text Available Digital forensics tools have many potential applications in the curation of digital materials in libraries, archives and museums (LAMs. Open source digital forensics tools can help LAM professionals to extract digital contents from born-digital media and make more informed preservation decisions. Many of these tools have ways to display the metadata of the digital media, but few provide file-level access without having to mount the device or use complex command-line utilities. This paper describes a project to develop software that supports access to the contents of digital media without having to mount or download the entire image. The work examines two approaches in creating this tool: First, a graphical user interface running on a local machine. Second, a web-based application running in web browser. The project incorporates existing open source forensics tools and libraries including The Sleuth Kit and libewf along with the Flask web application framework and custom Python scripts to generate web pages supporting disk image browsing.

  5. Tolerance of an expanding subarctic shrub, Betula glandulosa, to simulated caribou browsing.

    Directory of Open Access Journals (Sweden)

    Emilie Champagne

    Full Text Available Densification of the shrub layer has been reported in many subarctic regions, raising questions about the implication for large herbivores and their resources. Shrubs can tolerate browsing and their level of tolerance could be affected by browsing and soils productivity, eventually modifying resource availability for the caribou. Our objective was to assess the compensatory growth potential of a subarctic shrub, Betula glandulosa Michx., in relation with caribou browsing and nutriment availability for the plants. We used a simulated browsing (0, 25 and 75% of available shoots and nitrogen-fertilisation (0 and 10 g m(-2 experiment to test two main hypotheses linking tolerance to resource availability, the Compensatory Continuum Hypothesis and the Growth Rate Hypothesis as well as the predictions from the Limiting Resource Model. We seek to explicitly integrate the relative browsing pressure in our predictions since the amount of tissues removed could affect the capacity of long-lived plants to compensate. Birches fully compensated for moderate browsing with an overall leaf biomass similar to unbrowsed birches but undercompensated under heavy browsing pressure. The main mechanism explaining compensation appears to be the conversion of short shoots into long shoots. The leaf area increased under heavy browsing pressure but only led to undercompensation. Fertilisation for two consecutive years did not influence the response of birch, thus we conclude that our results support the LRM hypothesis of equal tolerance under both high and low nitrogen availability. Our results highlight that the potential for compensatory growth in dwarf birch is surpassed under heavy browsing pressure independently of the fertilisation regime. In the context of the worldwide decline in caribou herds, the reduction in browsing pressure could act synergistically with global climate change to promote the current shrub expansion reported in subarctic regions.

  6. Sliders Versus Storyboards - Investigating Interaction Design for Mobile Video Browsing

    NARCIS (Netherlands)

    Hürst, Wolfgang|info:eu-repo/dai/nl/313710589; Hoet, Miklas

    2015-01-01

    We present a comparative study of two different interfaces for mobile video browsing on tablet devices following two basic concepts - storyboard designs representing a video’s content in a grid-like arrangement of static images extracted from the file, and slider interfaces enabling users to

  7. Secure e-mail and Web browsing

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    This is an entry-level 1.5-hour training course aimed to show how to detect and avoid typical security pitfalls encountered when e-mailing and browsing the Web. It is designed for non-technical users of Internet Explorer and Outlook. Register at CTA

  8. Search the Audio, Browse the Video—A Generic Paradigm for Video Collections

    Directory of Open Access Journals (Sweden)

    Efrat Alon

    2003-01-01

    Full Text Available The amount of digital video being shot, captured, and stored is growing at a rate faster than ever before. The large amount of stored video is not penetrable without efficient video indexing, retrieval, and browsing technology. Most prior work in the field can be roughly categorized into two classes. One class is based on image processing techniques, often called content-based image and video retrieval, in which video frames are indexed and searched for visual content. The other class is based on spoken document retrieval, which relies on automatic speech recognition and text queries. Both approaches have major limitations. In the first approach, semantic queries pose a great challenge, while the second, speech-based approach, does not support efficient video browsing. This paper describes a system where speech is used for efficient searching and visual data for efficient browsing, a combination that takes advantage of both approaches. A fully automatic indexing and retrieval system has been developed and tested. Automated speech recognition and phonetic speech indexing support text-to-speech queries. New browsable views are generated from the original video. A special synchronized browser allows instantaneous, context-preserving switching from one view to another. The system was successfully used to produce searchable-browsable video proceedings for three local conferences.

  9. 3D shape recovery from image focus using gray level co-occurrence matrix

    Science.gov (United States)

    Mahmood, Fahad; Munir, Umair; Mehmood, Fahad; Iqbal, Javaid

    2018-04-01

    Recovering a precise and accurate 3-D shape of the target object utilizing robust 3-D shape recovery algorithm is an ultimate objective of computer vision community. Focus measure algorithm plays an important role in this architecture which convert the color values of each pixel of the acquired 2-D image dataset into corresponding focus values. After convolving the focus measure filter with the input 2-D image dataset, a 3-D shape recovery approach is applied which will recover the depth map. In this document, we are concerned with proposing Gray Level Co-occurrence Matrix along with its statistical features for computing the focus information of the image dataset. The Gray Level Co-occurrence Matrix quantifies the texture present in the image using statistical features and then applies joint probability distributive function of the gray level pairs of the input image. Finally, we quantify the focus value of the input image using Gaussian Mixture Model. Due to its little computational complexity, sharp focus measure curve, robust to random noise sources and accuracy, it is considered as superior alternative to most of recently proposed 3-D shape recovery approaches. This algorithm is deeply investigated on real image sequences and synthetic image dataset. The efficiency of the proposed scheme is also compared with the state of art 3-D shape recovery approaches. Finally, by means of two global statistical measures, root mean square error and correlation, we claim that this approach -in spite of simplicity generates accurate results.

  10. Both gas chromatography and an electronic nose reflect chemical polymorphism of juniper shrubs browsed or avoided by sheep.

    Science.gov (United States)

    Markó, Gábor; Novák, Ildikó; Bernáth, Jeno; Altbäcker, Vilmos

    2011-07-01

    Chemical polymorphism may contribute to variation in browsing damage by mammalian herbivores. Earlier, we demonstrated that essential oil concentration in juniper, Juniperus communis, was negatively associated with herbivore browsing. The aim of the present study was to characterize the volatile chemical composition of browsed and non-browsed J. communis. By using either gas chromatography with flame ionization detection (GC-FID) or an electronic nose device, we could separate sheep-browsed or non-browsed juniper shrubs by their essential oil pattern and complex odor matrix. The main components of the essential oil from J. communis were monoterpenes. We distinguished three chemotypes, dominated either by α-pinene, sabinene, or δ-3-carene. Shrubs belonging to the α-pinene- or sabinene-dominated groups were browsed, whereas all individuals with the δ-3-carene chemotype were unused by the local herbivores. The electronic nose also separated the browsed and non-browsed shrubs indicating that their odor matrix could guide sheep browsing. Responses of sheep could integrate the post-ingestive effects of plant secondary metabolites with sensory experience that stems from odor-phytotoxin interactions. Chemotype diversity could increase the survival rate in the present population of J. communis as certain shrubs could benefit from relatively better chemical protection against the herbivores.

  11. Browsing Patterns of White-Tailed Deer Following Increased Timber Harvest and a Decline in Population Density

    Directory of Open Access Journals (Sweden)

    Shawn M. Crimmins

    2010-01-01

    Full Text Available We examined browsing patterns of white-tailed deer (Odocoileus virginianus on a site in the central Appalachians that experienced a substantial (>50% reduction in deer population density and an increase in the amount of timber harvest since 2001. We sampled woody browse in and immediately adjacent to 12 clearcuts ranging in age from 0–5 years postharvest in summer 2007. Clearcut-interior areas had higher woody browse abundance and browsing rates than clearcut-edge or mature forest areas. Woody browse abundance was slightly higher within individual clearcuts than in 2001 at higher population densities and lower timber harvest rates. Overall browsing rates declined from approximately 17% in 2001 to less than 5% during our study, suggesting that the combination of deer population control, and increasing the amount of timber harvest across the landscape can reduce herbivory to levels that may not impede growth and survival of forest vegetation.

  12. AN INTEGRATED APPROACH FOR LINKED DATA BROWSING

    Directory of Open Access Journals (Sweden)

    W. Beek

    2017-07-01

    Full Text Available The Netherlands' Cadastre, Land Registry and Mapping Agency – in short Kadaster – collects and registers administrative and spatial data on property and the rights involved. Currently, the Kadaster is publishing its geo-spatial data assets as Linked Open Data. The Kadaster manages hundreds of datasets that describe hundreds of millions of geospatial objects, including all Dutch buildings, roads, and forests. The Kadaster exposes this large collection of data to thousands of daily users that operate from within different contexts and that need to be supported in different use cases. Therefore, Kadaster must offer diverse, yet complementary, approaches for browsing and exploring the data it publishes. Specifically, it supports the following paradigms for browsing and exploring its data assets: hierarchical browsing, graph navigation, faceted browsing, and tabular browsing. These paradigms are useful for different tasks, cover different use cases, and are implemented by reusing and/or developing Open Source libraries and applications.

  13. The tissue micro-array data exchange specification: a web based experience browsing imported data

    Science.gov (United States)

    Nohle, David G; Hackman, Barbara A; Ayers, Leona W

    2005-01-01

    Background The AIDS and Cancer Specimen Resource (ACSR) is an HIV/AIDS tissue bank consortium sponsored by the National Cancer Institute (NCI) Division of Cancer Treatment and Diagnosis (DCTD). The ACSR offers to approved researchers HIV infected biologic samples and uninfected control tissues including tissue cores in micro-arrays (TMA) accompanied by de-identified clinical data. Researchers interested in the type and quality of TMA tissue cores and the associated clinical data need an efficient method for viewing available TMA materials. Because each of the tissue samples within a TMA has separate data including a core tissue digital image and clinical data, an organized, standard approach to producing, navigating and publishing such data is necessary. The Association for Pathology Informatics (API) extensible mark-up language (XML) TMA data exchange specification (TMA DES) proposed in April 2003 provides a common format for TMA data. Exporting TMA data into the proposed format offers an opportunity to implement the API TMA DES. Using our public BrowseTMA tool, we created a web site that organizes and cross references TMA lists, digital "virtual slide" images, TMA DES export data, linked legends and clinical details for researchers. Microsoft Excel® and Microsoft Word® are used to convert tabular clinical data and produce an XML file in the TMA DES format. The BrowseTMA tool contains Extensible Stylesheet Language Transformation (XSLT) scripts that convert XML data into Hyper-Text Mark-up Language (HTML) web pages with hyperlinks automatically added to allow rapid navigation. Results Block lists, virtual slide images, legends, clinical details and exports have been placed on the ACSR web site for 14 blocks with 1623 cores of 2.0, 1.0 and 0.6 mm sizes. Our virtual microscope can be used to view and annotate these TMA images. Researchers can readily navigate from TMA block lists to TMA legends and to clinical details for a selected tissue core. Exports for 11

  14. Personalization of XML Content Browsing Based on User Preferences

    Science.gov (United States)

    Encelle, Benoit; Baptiste-Jessel, Nadine; Sedes, Florence

    2009-01-01

    Personalization of user interfaces for browsing content is a key concept to ensure content accessibility. In this direction, we introduce concepts that result in the generation of personalized multimodal user interfaces for browsing XML content. User requirements concerning the browsing of a specific content type can be specified by means of…

  15. Anonymous Web Browsing and Hosting

    OpenAIRE

    MANOJ KUMAR; ANUJ RANI

    2013-01-01

    In today’s high tech environment every organization, individual computer users use internet for accessing web data. To maintain high confidentiality and security of the data secure web solutions are required. In this paper we described dedicated anonymous web browsing solutions which makes our browsing faster and secure. Web application which play important role for transferring our secret information including like email need more and more security concerns. This paper also describes that ho...

  16. Silvicultural Attempts to Induce Browse Resistance in Conifer Seedlings

    Directory of Open Access Journals (Sweden)

    Bruce A. Kimball

    2011-01-01

    Full Text Available A multiyear study was conducted to determine if soil amendment combined with topical application of elemental sulfur could be employed to reduce deer browse damage to four conifer species. Fertilizer and sulfur were applied to conifer seedlings at seven sites near Corvallis, OR. Growth and browse damage data were collected for all seedlings over a period of 17 months. Additionally, foliar concentrations of monoterpenes and simple carbohydrates were assessed in western redcedar (Thuja plicata seedlings over a period of three years. Fertilization and sulfur treatments had a moderate impact on growth and no influence on browse damage or the chemical responses. Over the course of the study, browse damage diminished while foliar monoterpene concentrations increased in redcedar. It appears that silvicultural manipulation via sulfur application and/or soil amendment cannot accelerate or alter the ontogenetical changes that may naturally defend seedlings against mammalian herbivores. In a brief trial with captive deer, redcedar browse resistance was influenced by seedling maturation, but not monoterpene content. Other maturation effects may yield significant browse protection to young seedlings.

  17. Private Web Browsing

    National Research Council Canada - National Science Library

    Syverson, Paul F; Reed, Michael G; Goldschlag, David M

    1997-01-01

    .... These are both kept confidential from network elements as well as external observers. Private Web browsing is achieved by unmodified Web browsers using anonymous connections by means of HTTP proxies...

  18. In vitro fermentation of browse species using goat rumen fluid in relation to browse polyphenol content and composition

    NARCIS (Netherlands)

    Mengistu, G.; Karonen, M.; Salminen, J.P.; Hendriks, W.H.; Pellikaan, W.F.

    2017-01-01

    The effect of browse species tannins (using polyethylene glycol, PEG 6000) on in vitro gas production (GP), methane (CH 4 ), ammonia (NH 3 ), volatile fatty acids (VFA) and in vitro organic matter digestibility (IVOMD) were studied. Approximately 0.5 g of air-dried A. etbaica, C. farinosa, C.

  19. In vitro fermentation of browse species using goat rumen fluid in relation to browse polyphenol content and composition

    NARCIS (Netherlands)

    Mengistu, G.; Karonen, M; Salminen, J-P; Hendriks, W. H.; Pellikaan, Wilbert F

    2017-01-01

    The effect of browse species tannins (using polyethylene glycol, PEG 6000) on in vitro gas production (GP), methane (CH4), ammonia (NH3), volatile fatty acids (VFA) and in vitro organic matter digestibility (IVOMD) were studied. Approximately 0.5 g of air-dried A. etbaica, C. farinosa, C. tomentosa,

  20. Estimating 3D Object Parameters from 2D Grey-Level Images

    NARCIS (Netherlands)

    Houkes, Z.

    2000-01-01

    This thesis describes a general framework for parameter estimation, which is suitable for computer vision applications. The approach described combines 3D modelling, animation and estimation tools to determine parameters of objects in a scene from 2D grey-level images. The animation tool predicts

  1. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 437 ... Journal Home > Advanced Search > Browse Title Index ... prospects and realistic strategies to its implementation in Nigeria\\'s Institute of ... and Communication Technology (ICT) in information dissemination, Abstract.

  2. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 100 of 346 ... Journal Home > Advanced Search > Browse Title Index ... and hygiene promotion services in Rungwe district, Tanzania, Abstract .... as seen in NIgerian teaching hospital: pattern and a simple classification, Abstract.

  3. Fermentation characteristics and nutrient composition of browses ...

    African Journals Online (AJOL)

    Browses are important sources of feed and are widely used for animal nutrition to enhance productivity. They are commonly ensiled with other forages such as maize (Zea mays). However, the fermentation pattern and chemical composition of browses, that are commonly used are largely unknown. Thus, a study was carried ...

  4. Heavy browsing affects the hydraulic capacity of Ceanothus rigidus (Rhamnaceae).

    Science.gov (United States)

    Pittermann, Jarmila; Lance, Jonathan; Poster, Lauren; Baer, Alex; Fox, Laurel R

    2014-07-01

    Defoliation by herbivores can reduce carbon assimilation, change plant water relations, and even shift the biotic structure of plant communities. In this study, we took advantage of a long-term deer exclosure experiment to examine the consequences of persistent deer herbivory on plant water relations and the xylem structure-function relationships in Ceanothus rigidus, a maritime chaparral shrub in coastal California. Browsed plants had thicker stems with many intertwined short distal twigs, and significantly higher sapwood-to-leaf area ratios than their non-browsed counterparts. Leaf area-specific hydraulic conductivity was similar in both browsed and non-browsed plants, but xylem area-specific conductivity was significantly lower in the browsed plants. Vessel diameters were equivalent in both plant groups, but the number of vessels on a transverse area basis was nearly 40% lower in the browsed plants, accounting for their lower transport efficiency. Mid-day in situ water potentials and losses of hydraulic conductivity due to embolism were similar in both groups of plants but stomatal conductance was higher in the browsed shrubs in the early part of the growing season. We discuss our findings in the context of whole-plant ecophysiology, and explore the consequences of herbivory on hormonal signals, wood anatomy, and xylem function.

  5. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 183 ... Journal Home > Advanced Search > Browse Title Index ... Vol 61 (2017), New interventions and sustainable solutions: .... Vol 35 (2011), Resurgence of tribal levies: Double taxation for the rural poor, Abstract PDF.

  6. Browse Title Index

    African Journals Online (AJOL)

    Items 901 - 950 of 1355 ... Journal of Applied Sciences and Environmental Management. ... Journal Home > Advanced Search > Browse Title Index .... Vol 22, No 2 (2018), Performance evaluation of a locally fabricated sawdust fired oven for ...

  7. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 465 ... Journal Home > Advanced Search > Browse Title Index ... and twinning data of an igbo kindred during the Nigerian Civil War, Abstract ... on laboratory estimations with special reference to clinical chemistry, Abstract.

  8. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 644 ... Journal Home > Advanced Search > Browse Title Index. Log in or ... Ethics review n international health research: quality assurance or bureaucratic nightmare? Details ... Audit of Management of Open Fractures, Details PDF.

  9. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 165 ... Journal Home > Advanced Search > Browse Title Index ... Vol 43 (2011), Assessment of the Learning Commons takeoff at the University of ... the archive of South Africa's Truth and Reconciliation Commission, Abstract.

  10. Simulated browsing affects leaf shedding phenology and litter quality of oak and birch saplings

    OpenAIRE

    Palacio, Sara; Hester, A. J.; Maestro Martínez, Melchor; Millard, P.

    2013-01-01

    Herbivore effects on leaf litter can have a strong impact on ecosystem nutrient cycling. Although such effects are well described for insect herbivory, research on the impacts of browsing by mammalian herbivores on leaf litter dynamics and nutrient cycling has been more limited, particularly at the level of the individual plant. Clipping treatments (66% shoot removal twice, plus unclipped) were applied to analyse the effect of browsing on the phenology (start date and pattern of leaf shedding...

  11. Nutritive value of browses as protein supplement(s) to poor quality roughages

    NARCIS (Netherlands)

    Kaitho, R.J.

    1997-01-01

    In tropical and subtropical regions, pasture grasses and cereal residues are frequently low in nutrients especially protein and therefore cannot support high levels of ruminant production. Many browse species are endowed with high levels of protein and hence suitable as supplements. The

  12. A Privacy Analysis of Google and Yandex Safe Browsing

    OpenAIRE

    Gerbet , Thomas; Kumar , Amrit; Lauradoux , Cédric

    2015-01-01

    Google and Yandex Safe Browsing are popular services included in many webbrowsers to prevent users from visiting phishing or malware website links. If Safe Browsing servicesprotect their users from losing private information, they also require that their servers receivebrowsing information on the very same users. In this paper, we present an analysis of Googleand Yandex Safe Browsing services from a privacy perspective. We quantify the privacy providedby these services by analyzing the possib...

  13. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 879 ... South African Journal of Higher Education. ... Browse Title Index ... in a USA school setting: Merging transition theory with a narrative approach, Abstract ... Citation analysis of theses and dissertations submitted at the ...

  14. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 130 ... Journal Home > Advanced Search > Browse Title Index. Log in or ... using the technological pedagogical content knowledge(TPACK) framework, Abstract PDF ... Tamara N. Hrin, Dušica D. Milenković, Mirjana D. Segedinac.

  15. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 278 ... Journal Home > Advanced Search > Browse Title Index ... drie paradigmas beskou: 'n eenheid, of 'n veelheid van perspektiewe? ... Vol 45, No 1 (2011), Genre pedagogy in the mediation of socially-situated literacies ...

  16. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 147 ... Journal Home > Advanced Search > Browse Title Index .... Library (TEEAL) Database among faculty members in Federal University, ... Vol 5, No 2 (2014), Effects of corporate culture on the implementation of automation in ...

  17. Browse Title Index

    African Journals Online (AJOL)

    Items 201 - 250 of 531 ... Journal Home > Advanced Search > Browse Title Index ... thermal conductivity and viscosity in a flat plate solar collector, Abstract PDF .... similarity method in unsteady two-dimensional MHD boundary layer on the body ...

  18. Browse Title Index

    African Journals Online (AJOL)

    Items 601 - 650 of 879 ... South African Journal of Higher Education. ... Browse Title Index .... The challenge of thesis supervision in an art university, Abstract ... No 2 (2004), Robert Sternberg's mental self-government theory and its contribution to ...

  19. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 736 ... Journal Home > Advanced Search > Browse Title Index ... Vol 5 (2008), A Contagious Malady: The Human Quest for Truth through Religion, Abstract ... A Study of Politeness Strategies Used by the National University of ...

  20. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 879 ... Journal Home > Advanced Search > Browse Title Index ... Vol 20, No 4 (2006), Assessing academic potential for university admission: ... Vol 16, No 2 (2002), Book Review: Rethinking truth by Higgs, P & Smith, J, Details.

  1. Browse Title Index

    African Journals Online (AJOL)

    Items 451 - 500 of 533 ... Journal Home > Advanced Search > Browse Title Index .... for past tense forms in Northern Sotho: verb stems with final 'm' and 'n', Abstract ... in an academic writing class: Implications for a dialogic pedagogy, Abstract.

  2. Browse Title Index

    African Journals Online (AJOL)

    Items 301 - 350 of 788 ... Journal Home > Advanced Search > Browse Title Index ... Vol 26, No 1 (2018), Gender differentials in the perception of .... Vol 25, No 1 (2017), Impact of total quality management on students' academic performance in ...

  3. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 194 ... Journal Home > Advanced Search > Browse Title Index ... Vol 14, No 1 (2000), A functional categoriality of adjectives in ... Vol 1, No 1 (1987), Alienation and affirmation: The humanistic vision of Bessie Head, Abstract PDF.

  4. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 294 ... Journal Home > Advanced Search > Browse Title Index. Log in or .... S Edwards, M Hlongwane, J Thwala, N Robinson ... Vol 16, No 1 (2017), Infancy of internet cafe: The substitute of ubuntu-padare pedagogy, Abstract.

  5. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 98 ... Journal Home > Advanced Search > Browse Title Index ... model for the continued professionalisation of student affairs in Africa, Abstract PDF ... Vol 2, No 2 (2014), Book Review: How College Affects Students, A Third decade ...

  6. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 76 ... Journal Home > Advanced Search > Browse Title Index ... Vol 4, No 1 (2011), Automation of AutoCAD for Detailing of Reinforced .... Vol 10, No 1 (2017), Housing data base for sustainable housing provision, Abstract PDF.

  7. Does browsing reduce shrub survival and vigor following summer fires?

    Science.gov (United States)

    Fulbright, Timothy E.; Dacy, Emily C.; Drawe, D. Lynn

    2011-01-01

    Periodic fire is widely hypothesized to limit woody plant encroachment in semiarid grasslands. In southern Texas, however, most of the woody plants that have invaded grasslands during the past two centuries are resistant to fire. We hypothesized that browsing by Odocoileus virginianus increases mortality of palatable shrubs and reduces vigor of shrubs following fire. We randomly selected ten pairs of each of three shrub species -Condalia hookeri, Acacia farnesiana, and Celtis ehrenbergiana - in each of three locations before prescribed burns during summer 2001. Following burns, we used a wire fence to protect one shrub of each pair from browsing. We estimated intensity of O. virginianus browsing and number and height of sprouts 4, 12, 20, 30, 38, and 47 weeks post-fire. We determined shrub height, survival, and biomass one year post-fire. Averaged across species, browsing intensity on unfenced shrubs was greater (LS Means, P 0.05) one year post-burn. Browsing by O. virginianus at the intensity in our study does not increase mortality or reduce vigor of C. hookeri, A. farnesiana, and Condalia ehrenbergiana producing new growth following destruction of aboveground tissues by a single fire compared to shrubs that are not browsed following fire.

  8. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 73 of 73 ... Journal Home > Advanced Search > Browse Title Index ... Vol 13 (2006), The ageing eye” functional changes from cradle to gray: A ... Vol 12 (2005), The evaluation of vision in children using monocular vision acuity and ...

  9. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 100 of 391 ... Journal Home > Advanced Search > Browse Title Index ... Efficacy of four Rodenticides on the Ghanaian Market, Abstract ... Vol 2, No 1 (2000):, Determination of some wear elements in used car engine oil and oil filter ...

  10. Browse Title Index

    African Journals Online (AJOL)

    Items 251 - 300 of 652 ... Journal Home > Advanced Search > Browse Title Index ... Vol 18, No 7 (2015), Introduction to virtual property: Lex virtualis ipsa ... Vol 17, No 1 (2014), Legal challenges relating to the commercial use of outer space, with ...

  11. Browse Title Index

    African Journals Online (AJOL)

    Items 551 - 600 of 879 ... Journal Home > Advanced Search > Browse Title Index ... A James, E Ralfe, L van Laren, N Ngcobo ... 1 (2011), Recognition of prior learning in promoting lifelong learning: A pedagogy of hope or a shattering of dreams?

  12. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 97 of 97 ... Journal Home > Advanced Search > Browse Title Index ... Vol 20, No 2 (2008), Research Note: Anthropometric data of the foot of ... Vol 26, No 1 (2014), Validation of the Automation Attitude Questionnaire for Airline Pilots ...

  13. A Web Browsing Behavior Recording System

    OpenAIRE

    Ohmura, Hayato; Kitasuka, Teruaki; Aritsugi, Masayoshi; オオムラ, ハヤト; キタスカ, テルアキ; アリツギ, マサヨシ; 大村, 勇人; 北須賀, 輝明; 有次, 正義

    2011-01-01

    In this paper, we introduce a Web browsing behavior recording system for research. Web browsing behavior data can help us to providesophisticated services for human activities, because the data must indicate characteristics ofWeb users.We discuss the necessity of the data with potential benefits, and develop a system for collecting the data as an add-on for Firefox. We also report some results of preliminary experiments to test its usefulness in analyses on human activities in this paper.

  14. INFLUENCE OF SEMIARID SUMMER BROWSING ON CHEMICAL

    Directory of Open Access Journals (Sweden)

    Claudia Puga

    2009-06-01

    Full Text Available A group (A of 20 female French Alpine goats (50 ± 5 Kg BW were fed on summer semiarid vegetation in Querétaro, México. Other group (B with similar characteristic was fed in full confinement with Lucerne hay and concentrate of cereals. Four kids of cheese were prepared: 1 browsed-raw (BR, 2 browsed-pasteurized (BP, 3 indoor-raw (IR and 4 indoor-pasteurized (IP; using 30 kg of milk per group, 15 kg each group were proceed in raw and 15 kg each were pasteurized. Moisture, energy, protein, ash, lipids, cholesterol, fatty acids profile and CLA were determined in the cheeses; the results were analyzed with a variance analysis in a 2x2 factorial arrangement. Energy, fat and ash did not affect for feeding system and heat treatment. Protein content was higher in IP cheese compared with BR and BP cheeses. BR cheese had a lowest cholesterol value in relation to BP, IR and IP cheeses. The browed cheeses had the highest concentration of CLA, EPA and DHA acids in relation to indoor cheeses. Pasteurization did not have effect in cheese quality. Browsing increased concentration of compounds with a beneficial effect on human health, factor that could add revenue to the small farmer’s income.

  15. Browse Title Index

    African Journals Online (AJOL)

    Items 601 - 650 of 788 ... Browse Title Index ... Issue, Title ... Vol 14, No 1 (2006), Social science research: a critique of quantitative and qualitative methods ... Vol 18, No 1 (2010), Stress among part-time business students: a study in a Ghanaian ...

  16. Perbandingan proxy pada linux dan windows untuk mempercepat browsing website

    Directory of Open Access Journals (Sweden)

    Dafwen Toresa

    2017-05-01

    Full Text Available AbstrakPada saat ini sangat banyak organisasi, baik pendidikan, pemerintahan,  maupun perusahaan swasta berusaha membatasi akses para pengguna ke internet dengan alasan bandwidth yang dimiliki mulai terasa lambat ketika para penggunanya mulai banyak yang melakukan browsing ke internet. Mempercepat akses browsing menjadi perhatian utama dengan memanfaatkan teknologi Proxy server. Penggunaan proxy server perlu mempertimbangkan sistem operasi pada server dan tool yang digunakan belum diketahui performansi terbaiknya pada sistem operasi apa.  Untuk itu dirasa perlu untuk menganalisis performan Proxy server pada sistem operasi berbeda yaitu Sistem Operasi Linux dengan tools Squid  dan Sistem Operasi Windows dengan tool Winroute. Kajian ini dilakukan untuk mengetahui perbandingan kecepatan browsing dari komputer pengguna (client. Browser yang digunakan di komputer pengguna adalah Mozilla Firefox. Penelitian ini menggunakan 2 komputer klien dengan pengujian masing-masingnya 5 kali pengujian pengaksesan/browsing web yang dituju melalui proxy server. Dari hasil pengujian yang dilakukan, diperoleh kesimpulan bahwa penerapan proxy server di sistem operasi linux dengan tools squid lebih cepat browsing dari klien menggunakan web browser yang sama dan komputer klien yang berbeda dari pada proxy server sistem operasi windows dengan tools winroute.  Kata kunci: Proxy, Bandwidth, Browsing, Squid, Winroute AbstractAt this time very many organizations, both education, government, and private companies try to limit the access of users to the internet on the grounds that the bandwidth owned began to feel slow when the users began to do a lot of browsing to the internet. Speed up browsing access is a major concern by utilizing Proxy server technology. The use of proxy servers need to consider the operating system on the server and the tool used is not yet known the best performance on what operating system. For that it is necessary to analyze Performance Proxy

  17. Research on Browsing Behavior in the Libraries: An Empirical Analysis of Consequences, Success and Influences

    Directory of Open Access Journals (Sweden)

    Shan-Ju L. Chang

    2000-12-01

    Full Text Available Browsing as an important part of human information behavior has been observed and investigated in the context of information seeking in the library in general and has assumed greater importance in human-machine interaction in particular. However, the nature and consequences of browsing are not well understood, and little is known of the success rate of such behavior.In this research, exploratory empirical case studies from three types of libraries were conducted, using questionnaires, observation logs, interviews, and computer search logs, to derive the empirical evidence to understand, from the user point of view, what are the consequences of browsing, what constitutes successful browsing, and what factors influence the extent of browsing. Content analysis and statistical analysis were conducted to analyze and synthesize the data. The research results show: (1 There are nine categories of the consequence of browsing, including accidental findings, modification of information need, found the desirable information, learning, feeling relaxation/recreational, information gathering, keeping updated, satisfying curiosity, and not finding what is needed. (2 Four factors that produce successful browsing: intention, the amount or quality of information, the utility of what is found, and help for solving problem or making judgment. (3 Three types of reasons for unsuccessful experience in browsing: not finding what one wanted, inadequate volume or quality of information, and not finding some things useful or interesting. (4 Three types of reasons for partial success: found the intended object but not happy with the quality or amount of information in it, not finding what one wanted but discovering new or potential useful information, not accomplish one purpose but achieve another one given multiple purposes. (5 The influential factors that affect the extent one engages in browsing include browser’s time, scheme of information organization, proximity to

  18. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 229 ... Browse Title Index ... Issue, Title. Vol 14, No 2 ... Vol 15, No 1 (2017), Qualitative and quantitative methods of suicide research in old age, Abstract PDF ... Vol 11, No 2 (2013), Simple Algorithm in the Management of Fetal ...

  19. Responses of herbage and browse production to six range management strategies.

    Science.gov (United States)

    H. Reed Sanderson; Thomas M. Quigley; Arthur R. Tiedemann

    1990-01-01

    From 1977 through 1986, herbage and browse production was sampled on 619 sites representing 10 ecosystems and 51 resource units on the Oregon Range Evaluation study area. We determined the effects of six range management strategies and cultural treatments on combined herbage and browse production. Mean herbage and browse production on the forest ecosystems was 145...

  20. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bjorn N. P. Paulsson

    2006-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to perform high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology has been hampered by the lack of acquisition technology necessary to record large volumes of high frequency, high signal-to-noise-ratio borehole seismic data. This project took aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array has removed the technical acquisition barrier for recording the data volumes necessary to do high resolution 3D VSP and 3D cross-well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that promise to take the gas industry to the next level in their quest for higher resolution images of deep and complex oil and gas reservoirs. Today only a fraction of the oil or gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of detailed compartmentalization of oil and gas reservoirs. In this project, we developed a 400 level 3C borehole seismic receiver array that allows for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. This new array has significantly increased the efficiency of recording large data volumes at sufficiently dense spatial sampling to resolve reservoir complexities. The receiver pods have been fabricated and tested to withstand high temperature (200 C/400 F) and high pressure (25,000 psi), so that they can operate in wells up to 7,620 meters (25,000 feet) deep. The receiver array is deployed on standard production or drill tubing. In combination with 3C surface seismic or 3C borehole seismic sources, the 400

  1. Browse silage as potential feed for captive wild ungulates in southern Africa: A review

    Directory of Open Access Journals (Sweden)

    Khanyisile R. Mbatha

    2018-03-01

    Full Text Available The objective of the review was to assess the potential of indigenous browse trees as sustainable feed supplement in the form of silage for captive wild ungulates. Several attempts to use silage as feed in zoos in temperate regions have been conducted with success. Information on silage from the indigenous browse trees preferred by wild ungulates in southern Africa is scanty. The use of silage from the browse trees is of interest as it has potential to reduce or replace expensive feed sources (pellets, fruits and farm produce currently offered in southern African zoos, game farms and reserves, especially during the cold-dry season. Considerable leaf biomass from the indigenous browse trees can be produced for silage making. High nutrient content and minerals from indigenous browsable trees are highly recognised. Indigenous browse trees have low water-soluble carbohydrates (WSC that render them undesirable for fermentation. Techniques such as wilting browse leaves, mixing cereal crops with browse leaves, and use of additives such as urea and enzymes have been studied extensively to increase WSC of silage from the indigenous browse trees. Anti-nutritional factors from the indigenous browse preferred by the wild ungulates have also been studied extensively. Indigenous browse silages are a potential feed resource for the captive wild ungulates. If the browse trees are used to make silage, they are likely to improve performance of wild ungulates in captivity, especially during the cold-dry season when browse is scarce. Research is needed to assess the feasibility of sustainable production and the effective use of silage from indigenous browse trees in southern Africa. Improving intake and nutrient utilisation and reducing the concentrations of anti-nutritional compounds in silage from the indigenous browse trees of southern Africa should be the focus for animal nutrition research that need further investigation. Keywords: Anti-nutritional factors

  2. Note Taking and Note Sharing While Browsing Campaign Information

    DEFF Research Database (Denmark)

    Robertson, Scott P.; Vatrapu, Ravi; Abraham, George

    2009-01-01

    Participants were observed while searching and browsing the internet for campaign information in a mock-voting situation in three online note-taking conditions: No Notes, Private Notes, and Shared Notes. Note taking significantly influenced the manner in which participants browsed for information...

  3. 3D change detection at street level using mobile laser scanning point clouds and terrestrial images

    Science.gov (United States)

    Qin, Rongjun; Gruen, Armin

    2014-04-01

    Automatic change detection and geo-database updating in the urban environment are difficult tasks. There has been much research on detecting changes with satellite and aerial images, but studies have rarely been performed at the street level, which is complex in its 3D geometry. Contemporary geo-databases include 3D street-level objects, which demand frequent data updating. Terrestrial images provides rich texture information for change detection, but the change detection with terrestrial images from different epochs sometimes faces problems with illumination changes, perspective distortions and unreliable 3D geometry caused by the lack of performance of automatic image matchers, while mobile laser scanning (MLS) data acquired from different epochs provides accurate 3D geometry for change detection, but is very expensive for periodical acquisition. This paper proposes a new method for change detection at street level by using combination of MLS point clouds and terrestrial images: the accurate but expensive MLS data acquired from an early epoch serves as the reference, and terrestrial images or photogrammetric images captured from an image-based mobile mapping system (MMS) at a later epoch are used to detect the geometrical changes between different epochs. The method will automatically mark the possible changes in each view, which provides a cost-efficient method for frequent data updating. The methodology is divided into several steps. In the first step, the point clouds are recorded by the MLS system and processed, with data cleaned and classified by semi-automatic means. In the second step, terrestrial images or mobile mapping images at a later epoch are taken and registered to the point cloud, and then point clouds are projected on each image by a weighted window based z-buffering method for view dependent 2D triangulation. In the next step, stereo pairs of the terrestrial images are rectified and re-projected between each other to check the geometrical

  4. Medical high-resolution image sharing and electronic whiteboard system: A pure-web-based system for accessing and discussing lossless original images in telemedicine.

    Science.gov (United States)

    Qiao, Liang; Li, Ying; Chen, Xin; Yang, Sheng; Gao, Peng; Liu, Hongjun; Feng, Zhengquan; Nian, Yongjian; Qiu, Mingguo

    2015-09-01

    There are various medical image sharing and electronic whiteboard systems available for diagnosis and discussion purposes. However, most of these systems ask clients to install special software tools or web plug-ins to support whiteboard discussion, special medical image format, and customized decoding algorithm of data transmission of HRIs (high-resolution images). This limits the accessibility of the software running on different devices and operating systems. In this paper, we propose a solution based on pure web pages for medical HRIs lossless sharing and e-whiteboard discussion, and have set up a medical HRI sharing and e-whiteboard system, which has four-layered design: (1) HRIs access layer: we improved an tile-pyramid model named unbalanced ratio pyramid structure (URPS), to rapidly share lossless HRIs and to adapt to the reading habits of users; (2) format conversion layer: we designed a format conversion engine (FCE) on server side to real time convert and cache DICOM tiles which clients requesting with window-level parameters, to make browsers compatible and keep response efficiency to server-client; (3) business logic layer: we built a XML behavior relationship storage structure to store and share users' behavior, to keep real time co-browsing and discussion between clients; (4) web-user-interface layer: AJAX technology and Raphael toolkit were used to combine HTML and JavaScript to build client RIA (rich Internet application), to meet clients' desktop-like interaction on any pure webpage. This system can be used to quickly browse lossless HRIs, and support discussing and co-browsing smoothly on any web browser in a diversified network environment. The proposal methods can provide a way to share HRIs safely, and may be used in the field of regional health, telemedicine and remote education at a low cost. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Are 3-D Movies Bad for Your Eyes?

    Medline Plus

    Full Text Available ... 3-D digital images. Find an Ophthalmologist Advanced Search Ask an Ophthalmologist Browse Answers Free Newsletter Get ophthalmologist-reviewed tips and information about eye health and preserving your vision. Privacy ...

  6. Simulating ungulate herbivory across forest landscapes: A browsing extension for LANDIS-II

    Science.gov (United States)

    DeJager, Nathan R.; Drohan, Patrick J.; Miranda, Brian M.; Sturtevant, Brian R.; Stout, Susan L.; Royo, Alejandro; Gustafson, Eric J.; Romanski, Mark C.

    2017-01-01

    Browsing ungulates alter forest productivity and vegetation succession through selective foraging on species that often dominate early succession. However, the long-term and large-scale effects of browsing on forest succession are not possible to project without the use of simulation models. To explore the effects of ungulates on succession in a spatially explicit manner, we developed a Browse Extension that simulates the effects of browsing ungulates on the growth and survival of plant species cohorts within the LANDIS-II spatially dynamic forest landscape simulation model framework. We demonstrate the capabilities of the new extension and explore the spatial effects of ungulates on forest composition and dynamics using two case studies. The first case study examined the long-term effects of persistently high white-tailed deer browsing rates in the northern hardwood forests of the Allegheny National Forest, USA. In the second case study, we incorporated a dynamic ungulate population model to simulate interactions between the moose population and boreal forest landscape of Isle Royale National Park, USA. In both model applications, browsing reduced total aboveground live biomass and caused shifts in forest composition. Simulations that included effects of browsing resulted in successional patterns that were more similar to those observed in the study regions compared to simulations that did not incorporate browsing effects. Further, model estimates of moose population density and available forage biomass were similar to previously published field estimates at Isle Royale and in other moose-boreal forest systems. Our simulations suggest that neglecting effects of browsing when modeling forest succession in ecosystems known to be influenced by ungulates may result in flawed predictions of aboveground biomass and tree species composition.

  7. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 985 ... Journal Home > Advanced Search > Browse Title Index ... Vol 17 (2010), Alternating Direction Implicit Finite Difference Time Domain Acoustic Wave Algorithm, Abstract. E Ikata .... Vol 17 (2010), Analytic derivation of the wave profile and phase speed of sixth order Stokes waves in deep water, Abstract.

  8. Woody browse production

    Science.gov (United States)

    Tom Crow; Forest Stearns

    1992-01-01

    Sugar maple has great potential as wildlife food, especially as good winter fare for deer in the northern Lake States. Deer will diligently seek out sugar maple browse in the hardwood forests along the edges of a winter yard or in isolated islands of upland forest within a yard.

  9. Simulating browse production and response of Acacia karroo to ...

    African Journals Online (AJOL)

    Even if it is possible to reduce stock in times of drought, this was shown to be of very little benefit. Keywords: acacia karroo; browse production; browsing; defoliation; drought; eastern cape; goats; growth; management; management strategy; model; number of camps; production; productivity; simulation model; south africa; ...

  10. Extracting 3D layout from a single image using global image structures.

    Science.gov (United States)

    Lou, Zhongyu; Gevers, Theo; Hu, Ninghang

    2015-10-01

    Extracting the pixel-level 3D layout from a single image is important for different applications, such as object localization, image, and video categorization. Traditionally, the 3D layout is derived by solving a pixel-level classification problem. However, the image-level 3D structure can be very beneficial for extracting pixel-level 3D layout since it implies the way how pixels in the image are organized. In this paper, we propose an approach that first predicts the global image structure, and then we use the global structure for fine-grained pixel-level 3D layout extraction. In particular, image features are extracted based on multiple layout templates. We then learn a discriminative model for classifying the global layout at the image-level. Using latent variables, we implicitly model the sublevel semantics of the image, which enrich the expressiveness of our model. After the image-level structure is obtained, it is used as the prior knowledge to infer pixel-wise 3D layout. Experiments show that the results of our model outperform the state-of-the-art methods by 11.7% for 3D structure classification. Moreover, we show that employing the 3D structure prior information yields accurate 3D scene layout segmentation.

  11. An Automatic Cloud Detection Method for ZY-3 Satellite

    Directory of Open Access Journals (Sweden)

    CHEN Zhenwei

    2015-03-01

    Full Text Available Automatic cloud detection for optical satellite remote sensing images is a significant step in the production system of satellite products. For the browse images cataloged by ZY-3 satellite, the tree discriminate structure is adopted to carry out cloud detection. The image was divided into sub-images and their features were extracted to perform classification between clouds and grounds. However, due to the high complexity of clouds and surfaces and the low resolution of browse images, the traditional classification algorithms based on image features are of great limitations. In view of the problem, a prior enhancement processing to original sub-images before classification was put forward in this paper to widen the texture difference between clouds and surfaces. Afterwards, with the secondary moment and first difference of the images, the feature vectors were extended in multi-scale space, and then the cloud proportion in the image was estimated through comprehensive analysis. The presented cloud detection algorithm has already been applied to the ZY-3 application system project, and the practical experiment results indicate that this algorithm is capable of promoting the accuracy of cloud detection significantly.

  12. Browsing the Internet: good-bye anonymity!

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Do you consider browsing the Internet to be your private business? When visiting random web-sites, how far do you assume you are anonymous? Would it matter to you that Google or Facebook can profile your browsing behaviour in order to better target you with advertisements? Did you notice that you already get targeted ads when you are logged on to Google or Facebook even if you are visiting completely different websites? If matters to you, note that browsing anonymously on the Internet is far from easy.   When you are connected to the Internet, you give away a variety of information: your PC’s IP address, some browser settings like language or screen size, and, probably, your login information. So how private is private? You might argue that your current IP address has been picked from a pool of addresses and therefore regularly changes, so it does not necessarily always pinpoint you. On the other hand, with the dawn of IPv6 there is no need any more for shared IP addresses as the...

  13. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 28 of 28 ... Vol 1, No 2 (2006), Cotton [Gossipium hirsutum] and maize [Zea mays] yield losses due to weeds in Muzarabani, Zimbabwe, Abstract PDF ... given forage and a tree browse legume as supplements to the conventional dairy concentrate and a basal diet of Katambora Rhodes (Chloris gayana) grass hay.

  14. Browse Title Index

    African Journals Online (AJOL)

    Items 201 - 250 of 661 ... Journal Home > Advanced Search > Browse Title Index. Log in or Register to get access to full text downloads. .... A El-Mahdy, B Bolduc, J Upadhyay, R Shoukr, A Khoury. Vol 19, No 1 (2013), Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy, Abstract PDF.

  15. Determining Dry Matter Degradability of Some Semi-Arid Browse ...

    African Journals Online (AJOL)

    acer

    ABSTRACT: The in vitro gas production of some semi-arid browse species were evaluated. The relationship between in ... between in vitro gas measured on incubation of browse leaves and that calculated from SCFA allows the prediction of SCFA from ... with concentrate feed (40% corn, 10% wheat offal, 10% palm kernel ...

  16. Browse Title Index

    African Journals Online (AJOL)

    Items 1 - 50 of 217 ... Browse Title Index. Journal Home > Advanced ... Vol 13, No 1 (2016), Access to specialized surgical care, Abstract PDF. H Saidi ... Vol 9, No 2 (2012), Clinical Assessment of the Palmaris Longus – Accuracy of common tests, Abstract PDF ... Vol 11, No 2 (2014), Clinical trials in Surgery, Abstract PDF.

  17. Product features and task effects on experienced richness, control and engagement in voicemail browsing

    NARCIS (Netherlands)

    Rozendaal, M.C.; Keyson, D.V.; De Ridder, H.

    2008-01-01

    A recent focus is on creating engaging user experiences with digital products and services such as voicemail. This study aims to design towards increased levels of engagement in voicemail browsing by using the ‘Richness, Control and Engagement’ (RC & E) framework. This framework explains the levels

  18. Product features and task effects on experienced richness, control and engagement in voicemail browsing

    NARCIS (Netherlands)

    Rozendaal, M.C.; Keyson, D.V.; Ridder, de H.

    2009-01-01

    A recent focus is on creating engaging user experiences with digital products and services such as voicemail. This study aims to design towards increased levels of engagement in voicemail browsing by using the ‘Richness, Control and Engagement’ (RC & E) framework. This framework explains the levels

  19. Browse Title Index

    African Journals Online (AJOL)

    Items 101 - 150 of 1215 ... Journal Home > Advanced Search > Browse Title Index. Log in or ... Vol 12, No 1 (2018), Analysis of the effects of frequent strikes on academic performance of students in universities in Nigeria: Edo State as a focal point, Abstract PDF ... Vol 6, No 1 (2012), Appraisal as a Determinant for Adequate ...

  20. Development of Northern White-Cedar Regeneration Following Partial Cutting, with and without Deer Browsing

    Directory of Open Access Journals (Sweden)

    Catherine Larouche

    2015-02-01

    Full Text Available Northern white-cedar (Thuja occidentalis L. is an important commercial species with a high wildlife value, both as a food source and habitat for many bird and mammal species. Concerns have been expressed about its decreasing abundance across its range, and especially in mixedwood stands, where it has to compete with several other species and can suffer from heavy browsing. In this study, we quantified the development of natural northern white-cedar seedlings and saplings under various partial cutting regimes, with and without white-tailed deer (Odocoileus virgianus Zimmerman browsing, in three selected sites in Quebec (Canada and in Maine (USA. Our data show that northern white-cedar regeneration was present in all studied stands, but that only a few stems were taller than 30 cm on the two sites with high densities of deer. In the absence of heavy browsing, stems reached a height of 30 cm in 11 years, and 130 cm in 28 years. Height growth of northern white-cedar regeneration increased with canopy light transmittance, while ground-level diameter increment increased after partial cutting. This suggests that partial cutting can be used in mixedwood stands to release natural northern white-cedar regeneration, but also that the recruitment of northern white-cedar seedlings to larger size classes constitutes a major challenge in stands subject to heavy deer browsing.

  1. Ungulate browsing maintains shrub diversity in the absence of episodic disturbance in seasonally-arid conifer forest.

    Directory of Open Access Journals (Sweden)

    Burak K Pekin

    Full Text Available Ungulates exert a strong influence on the composition and diversity of vegetation communities. However, little is known about how ungulate browsing pressure interacts with episodic disturbances such as fire and stand thinning. We assessed shrub responses to variable browsing pressure by cattle and elk in fuels treated (mechanical removal of fuels followed by prescribed burning and non-fuels treated forest sites in northeastern Oregon, US. Seven treatment paddocks were established at each site; three with cattle exclusion and low, moderate and high elk browsing pressure, three with elk exclusion and low, moderate and high cattle browsing pressure, and one with both cattle and elk exclusion. The height, cover and number of stems of each shrub species were recorded at multiple plots within each paddock at the time of establishment and six years later. Changes in shrub species composition over the six year period were explored using multivariate analyses. Generalized Linear Mixed Models were used to determine the effect of browsing pressure on the change in shrub diversity and evenness. Vegetation composition in un-browsed paddocks changed more strongly and in different trajectories than in browsed paddocks at sites that were not fuels treated. In fuels treated sites, changes in composition were minimal for un-browsed paddocks. Shrub diversity and evenness decreased strongly in un-browsed paddocks relative to paddocks with low, moderate and high browsing pressure at non-fuels treated sites, but not at fuels treated sites. These results suggest that in the combined absence of fire, mechanical thinning and ungulate browsing, shrub diversity is reduced due to increased dominance by certain shrub species which are otherwise suppressed by ungulates and/or fuels removal. Accordingly, ungulate browsing, even at low intensities, can be used to suppress dominant shrub species and maintain diversity in the absence of episodic disturbance events.

  2. Shape-based grey-level image interpolation

    International Nuclear Information System (INIS)

    Keh-Shih Chuang; Chun-Yuan Chen; Ching-Kai Yeh

    1999-01-01

    The three-dimensional (3D) object data obtained from a CT scanner usually have unequal sampling frequencies in the x-, y- and z-directions. Generally, the 3D data are first interpolated between slices to obtain isotropic resolution, reconstructed, then operated on using object extraction and display algorithms. The traditional grey-level interpolation introduces a layer of intermediate substance and is not suitable for objects that are very different from the opposite background. The shape-based interpolation method transfers a pixel location to a parameter related to the object shape and the interpolation is performed on that parameter. This process is able to achieve a better interpolation but its application is limited to binary images only. In this paper, we present an improved shape-based interpolation method for grey-level images. The new method uses a polygon to approximate the object shape and performs the interpolation using polygon vertices as references. The binary images representing the shape of the object were first generated via image segmentation on the source images. The target object binary image was then created using regular shape-based interpolation. The polygon enclosing the object for each slice can be generated from the shape of that slice. We determined the relative location in the source slices of each pixel inside the target polygon using the vertices of a polygon as the reference. The target slice grey-level was interpolated from the corresponding source image pixels. The image quality of this interpolation method is better and the mean squared difference is smaller than with traditional grey-level interpolation. (author)

  3. Web User Profiling Based on Browsing Behavior Analysis

    OpenAIRE

    Fan , Xiao-Xi; Chow , Kam-Pui; Xu , Fei

    2014-01-01

    Part 1: Internet Crime Investigations; International audience; Determining the source of criminal activity requires a reliable means to estimate a criminal’s identity. One way to do this is to use web browsing history to build a profile of an anonymous user. Since an individual’s web use is unique, matching the web use profile to known samples provides a means to identify an unknown user. This paper describes a model for web user profiling and identification. Two aspects of browsing behavior ...

  4. The UCL NASA 3D-RPIF Imaging Centre - a status report.

    Science.gov (United States)

    Muller, J.-P.; Grindrod, P.

    2013-09-01

    The NASA RPIF (Regional Planetary Imaging Facility) network of 9 US and 8 international centres were originally set-up in 1977 to "maintain photographic and digital data as well as mission documentation and cartographic data. Each facility's general holding contains images and maps of planets and their satellites taken by solar system exploration spacecraft. These planetary image facilities are open to the public. The facilities are primarily reference centers for browsing, studying, and selecting lunar and planetary photographic and cartographic materials. Experienced staff can assist scientists, educators, students, media, and the public in ordering materials for their own use." In parallel, the NASA Planetary Data System (PDS) and ESA Planetary Science Archive (PSA) were set-up to distribute digital data initially on media such as CDROM and DVD but now entirely online. The UK NASA RPIF was the first RPIF to be established outside of the US, in 1980. In [1], the 3D-RPIF is described. Some example products derived using this equipment are illustrated here. In parallel, at MSSL a large linux cluster and associated RAID_based system has been created to act as a mirror PDS Imaging node so that huge numbers of rover imagery (from MER & MSL to begin with) and very high resolution (large size) data is available to users of the RPIF and a variety of EU-FP7 projects based at UCL.

  5. Foliar Nutritional Quality Explains Patchy Browsing Damage Caused by an Invasive Mammal.

    Directory of Open Access Journals (Sweden)

    Hannah R Windley

    Full Text Available Introduced herbivores frequently inflict significant, yet patchy damage on native ecosystems through selective browsing. However, there are few instances where the underlying cause of this patchy damage has been revealed. We aimed to determine if the nutritional quality of foliage could predict the browsing preferences of an invasive mammalian herbivore, the common brushtail possum (Trichosurus vulpecula, in a temperate forest in New Zealand. We quantified the spatial and temporal variation in four key aspects of the foliar chemistry (total nitrogen, available nitrogen, in vitro dry matter digestibility and tannin effect of 275 trees representing five native tree species. Simultaneously, we assessed the severity of browsing damage caused by possums on those trees in order to relate selective browsing to foliar nutritional quality. We found significant spatial and temporal variation in nutritional quality among individuals of each tree species examined, as well as among tree species. There was a positive relationship between the available nitrogen concentration of foliage (a measure of in vitro digestible protein and the severity of damage caused by browsing by possums. This study highlights the importance of nutritional quality, specifically, the foliar available nitrogen concentration of individual trees, in predicting the impact of an invasive mammal. Revealing the underlying cause of patchy browsing by an invasive mammal provides new insights for conservation of native forests and targeted control of invasive herbivores in forest ecosystems.

  6. Reading Culture and Internet Browsing: A Shift of Paradigm among ...

    African Journals Online (AJOL)

    Four hypotheses were tested to confirm the average number of hours the participants devout to browsing on one hand and to reading on the other, identify gender difference in respondents' perception of the time they spend and what they use the time for and if their browsing indeed have any impact on their reading habit.

  7. Some sauropods raised their necks—evidence for high browsing in Euhelopus zdanskyi

    Science.gov (United States)

    Christian, Andreas

    2010-01-01

    A very long neck that is apparently suitable for feeding at great heights is a characteristic feature of most sauropod dinosaurs. Yet, it remains controversial whether any sauropods actually raised their necks high. Recently, strong physiological arguments have been put forward against the idea of high-browsing sauropods, because of the very high blood pressure that appears to be inevitable when the head is located several metres above the heart. For the sauropod Euhelopus zdanskyi, however, biomechanical evidence clearly indicates high browsing. Energy expenditure owing to high browsing is compared with energy costs for walking a distance. It is demonstrated for Euhelopus as well as for the much larger Brachiosaurus that despite an increase in the metabolic rate, high browsing was worthwhile for a sauropod if resources were far apart. PMID:20519198

  8. Some sauropods raised their necks--evidence for high browsing in Euhelopus zdanskyi.

    Science.gov (United States)

    Christian, Andreas

    2010-12-23

    A very long neck that is apparently suitable for feeding at great heights is a characteristic feature of most sauropod dinosaurs. Yet, it remains controversial whether any sauropods actually raised their necks high. Recently, strong physiological arguments have been put forward against the idea of high-browsing sauropods, because of the very high blood pressure that appears to be inevitable when the head is located several metres above the heart. For the sauropod Euhelopus zdanskyi, however, biomechanical evidence clearly indicates high browsing. Energy expenditure owing to high browsing is compared with energy costs for walking a distance. It is demonstrated for Euhelopus as well as for the much larger Brachiosaurus that despite an increase in the metabolic rate, high browsing was worthwhile for a sauropod if resources were far apart.

  9. IOOS Data Portals and Uniform On-line Browse Capabilities

    Science.gov (United States)

    Howard, M.; Currier, R. D.; Kobara, S.; Gayanilo, F.

    2015-12-01

    The Gulf of Mexico Coastal Ocean Observing System Regional Association (GCOOS-RA) is one of eleven Regional Associations organized under the NOAA-led U.S. Integrated Ocean Observing System (IOOS) Program Office. Each of the RAs operate standards-based regional data portals designed to aggregate near real-time and historical observed data and modeled outputs from distributed providers and to offer these and derived products in standardized ways to a diverse set of users. The RA's portals are based on the IOOS Data and Communications Plan which describes the functional elements needed for an interoperable system. One of these elements is called "Uniform On-line Browse" which is an informational service designed primarily to visualize the inventory of a portal. An on-line browse service supports the end user's need to discover what parameters are available, to learn the spatial and temporal extend of the holdings, and to examine the character of the data (e.g, variability, gappiness, etc). These pieces of information help the end user decide if the data are fit for his/her purpose and to construct valid data requests. Note that on-line browse is a distinctly different activity than data analysis because it seeks to yield knowledge about the inventory and not about what the data mean. "Uniform" on-line browse is a service that takes advantage of the standardization of the data portal's data access points. Most portals represent station locations on a map. This is a view of the data inventory but these plots are rarely generated by pulling data through the standards-based services offered to the end users but through methods only available to the portal programmers. This work will present results of Uniform On-line browse tools developed within GCOOS-RA and their applicability to other RA portals.

  10. Effect of tropical browse leaves supplementation on rumen enzymes of sheep and goats fed Dichanthium annulatum grass-based diets.

    Science.gov (United States)

    Singh, Sultan; Kundu, S S

    2010-08-01

    In a switch-over experiment, eight male animals, four each of sheep and goats of local breeds with mean body weight of 26. 8 +/- 2.0 and 30.0 +/- 2.1 kg, were fed Dichanthium annulatum (DA) grass and four browse species viz. Helictris isora, Securengia virosa, Leucaena leucocephala (LL) and Hardwickia binnata (HB) in four feeding trials to assess their supplementary effect on activity of rumen enzymes. The sheep and goats were offered DA grass with individual browse in 75:25 and 50:50 proportions, respectively, for more than 3 months during each feeding trial, and rumen liquor samples were collected twice at 0 and 4 h post feeding after 60 and 90 days of feeding. Glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and glutamate dehydrogenase (GDH) enzymes were determined in the bacteria and protozoa fractions of rumen liquor, while cellulase enzyme activity was measured in mixed rumen liquor. LL and HB had the highest and lowest contents of CP, while fibre contents were lower in early than later browse leaves. Supplementation of browse leaves significantly (P goats on all DA grass-browse-supplemented diets except DA-HB (42.8 units/mg protein), where activity was significantly (P Goat exhibited higher activities of GOT and GPT than sheep in both bacteria and protozoa fraction of rumen liquor, while cellulase activity was similar between the animal species on the grass-browse leaves diets. Results indicate that browse leaves supplementation affect the enzyme activities of sheep and goats rumen, while the goats rumen liquor had higher activities of GOT, GPT and GDH enzyme than sheep.

  11. Response of northern red oak, black walnut, and white ash seedlings to various levels of simulated summer deer browsing

    Science.gov (United States)

    Robert C. Morrissey; Douglass F. Jacobs; John R. Seifert

    2008-01-01

    Understanding the response of tree seedlings to browsing by white-tailed deer (Odocoileus virginianus Zimmerman) is critical to the management of high value hardwood plantations in the Central Hardwood Forest Region. One-year-old black walnut (Juglans nigra L.), northern red oak (Quercus rubra L.), and white ash...

  12. Interpretation of medical imaging data with a mobile application: a mobile digital imaging processing environment

    Directory of Open Access Journals (Sweden)

    Meng Kuan eLin

    2013-07-01

    Full Text Available Digital Imaging Processing (DIP requires data extraction and output from a visualization tool to be consistent. Data handling and transmission between the server and a user is a systematic process in service interpretation. The use of integrated medical services for management and viewing of imaging data in combination with a mobile visualization tool can be greatly facilitated by data analysis and interpretation. This paper presents an integrated mobile application and digital imaging processing service, called M-DIP. The objective of the system is to (1 automate the direct data tiling, conversion, pre-tiling of brain images from Medical Imaging NetCDF (MINC, Neuroimaging Informatics Technology Initiative (NIFTI to RAW formats; (2 speed up querying of imaging measurement; and (3 display high level of images with three dimensions in real world coordinates. In addition, M-DIP provides the ability to work on a mobile or tablet device without any software installation using web-based protocols. M-DIP implements three levels of architecture with a relational middle- layer database, a stand-alone DIP server and a mobile application logic middle level realizing user interpretation for direct querying and communication. This imaging software has the ability to display biological imaging data a multiple zoom levels and to increase its quality to meet users expectations. Interpretation of bioimaging data is facilitated by an interface analogous to online mapping services using real world coordinate browsing. This allows mobile devices to display multiple datasets simultaneously from a remote site. M-DIP can be used as a measurement repository that can be accessed by any network environment, such as a portable mobile or tablet device. In addition, this system and combination with mobile applications are establishing a virtualization tool in the neuroinformatics field to speed interpretation services.

  13. Interpretation of medical imaging data with a mobile application: a mobile digital imaging processing environment.

    Science.gov (United States)

    Lin, Meng Kuan; Nicolini, Oliver; Waxenegger, Harald; Galloway, Graham J; Ullmann, Jeremy F P; Janke, Andrew L

    2013-01-01

    Digital Imaging Processing (DIP) requires data extraction and output from a visualization tool to be consistent. Data handling and transmission between the server and a user is a systematic process in service interpretation. The use of integrated medical services for management and viewing of imaging data in combination with a mobile visualization tool can be greatly facilitated by data analysis and interpretation. This paper presents an integrated mobile application and DIP service, called M-DIP. The objective of the system is to (1) automate the direct data tiling, conversion, pre-tiling of brain images from Medical Imaging NetCDF (MINC), Neuroimaging Informatics Technology Initiative (NIFTI) to RAW formats; (2) speed up querying of imaging measurement; and (3) display high-level of images with three dimensions in real world coordinates. In addition, M-DIP provides the ability to work on a mobile or tablet device without any software installation using web-based protocols. M-DIP implements three levels of architecture with a relational middle-layer database, a stand-alone DIP server, and a mobile application logic middle level realizing user interpretation for direct querying and communication. This imaging software has the ability to display biological imaging data at multiple zoom levels and to increase its quality to meet users' expectations. Interpretation of bioimaging data is facilitated by an interface analogous to online mapping services using real world coordinate browsing. This allows mobile devices to display multiple datasets simultaneously from a remote site. M-DIP can be used as a measurement repository that can be accessed by any network environment, such as a portable mobile or tablet device. In addition, this system and combination with mobile applications are establishing a virtualization tool in the neuroinformatics field to speed interpretation services.

  14. JHelioviewer: Exploring Petabytes of Solar Images

    Science.gov (United States)

    Mueller, Daniel; Fleck, Bernhard; Dimitoglou, George; Garcia Ortiz, Juan Pablo; Schmidt, Ludwig; Hughitt, Keith; Ireland, Jack

    Space missions generate an ever-growing amount of data, as impressively highlighted by the Solar Dynamics Observatory's (SDO) expected return of 1.4 TByte/day. In order to fully ex-ploit their data, scientists need to be able to browse and visualize many different data products spanning a large range of physical length and time scales. So far, the tools available to the scientific community either require downloading all potentially relevant data sets beforehand in their entirety or provide only movies with a fixed resolution and cadence. For SDO, the former approach is prohibitive due to the shear data volume, while the latter does not do justice to the high resolution and cadence of the images. To address this challenge, we have developed JHelioviewer, a JPEG 2000-based visualization and discovery software for solar image data. JHelioviewer makes the vast amount of SDO images available to the worldwide community, lets users browse more than 14 years worth of images from the Solar and Heliospheric Observatory (SOHO) and facilitates browsing and analysis of complex time-dependent data sets from mul-tiple sources in general. The user interface for JHelioviewer is a multi-platform Java client that communicates with a remote server via the JPEG 2000 interactive protocol JPIP. The random code stream access of JPIP minimizes data transfer and can encapsulate metadata as well as multiple image channels in one data stream. This presentation will illustrate the features of JHelioviewer and highlight the advantages of JPEG 2000 as a new data compression standard.

  15. Review article: Vegetative growth, reproduction, browse production ...

    African Journals Online (AJOL)

    Vegetative growth, reproduction, browse production and response to tree clearing of ... water stress, soil nutrient availability, carbohydrate reserves, plant hormones, ... animal-plant interactions) of woody plants in various savanna ecosystems.

  16. Indexing, learning and content-based retrieval for special purpose image databases

    NARCIS (Netherlands)

    M.J. Huiskes (Mark); E.J. Pauwels (Eric)

    2005-01-01

    textabstractThis chapter deals with content-based image retrieval in special purpose image databases. As image data is amassed ever more effortlessly, building efficient systems for searching and browsing of image databases becomes increasingly urgent. We provide an overview of the current

  17. Willow Browse Survey 2016 : Biological Summary Report

    Data.gov (United States)

    Department of the Interior — Browse pressure by ungulate species, primarily elk, is known to have a negative impact on the health of willow stands. On Baca and Alamosa NWR’s, it has been noticed...

  18. Willow Browse Survey 2015 : Biological Summary Report

    Data.gov (United States)

    Department of the Interior — Browse pressure by ungulate species, primarily elk, is known to have a negative impact on the health of willow stands. On Baca and Alamosa NWR’s, it has been noticed...

  19. Voice-controlled Internet Browsing for Motor-handicapped Users

    DEFF Research Database (Denmark)

    Brøndsted, Tom; Aaskoven, Erik

    2006-01-01

    The public-funded project "Indtal" ("Speak-it") has succeeded in developing a Danish voice-controlled utility for internet browsing targeting motor-handicapped users having difficulties using a standard keyboard and/or a standard mouse. The system has been designed and implemented in collaboration...... with an advisory board of motor-handicapped (potential) end-users and underlies a number of a priori defined design criteria: learnability and memorability rather than naturalness, minimal need for maintenance after release, support for "all" web standards (not just HTML conforming to certain "recommendations......"), independency of the language on the websites being browsed, etc. These criteria have lead to a primarily message-driven system interacting with an existing browser on the end users' systems...

  20. Design and implement of system for browsing remote seismic waveform based on B/S schema

    International Nuclear Information System (INIS)

    Zheng Xuefeng; Shen Junyi; Wang Zhihai; Sun Peng; Jin Ping; Yan Feng

    2006-01-01

    Browsing remote seismic waveform based on B/S schema is of significance in modern seismic research and data service, and the technology should be improved urgently. This paper describes the basic plan, architecture and implement of system for browsing remote seismic waveform based on B/S schema. The problem to access, browse and edit the waveform data on serve from client only using browser has been solved. On this basis, the system has been established and been in use. (authors)

  1. Factors affecting ANKOM™ fiber analysis of forage and browse varying in condensed tannin concentration.

    Science.gov (United States)

    Terrill, Thomas H; Wolfe, Richard M; Muir, James P

    2010-12-01

    Browse species containing condensed tannins (CTs) are an important source of nutrition for grazing/browsing livestock and wildlife in many parts of the world, but information on fiber concentration and CT-fiber interactions for these plants is lacking. Ten forage or browse species with a range of CT concentrations were oven dried and freeze dried and then analyzed for ash-corrected neutral detergent fiber (NDFom) and corrected acid detergent fiber (ADFom) using separate samples (ADFSEP) and sequential NDF-ADF analysis (ADFSEQ) with the ANKOM™ fiber analysis system. The ADFSEP and ADFSEQ residues were then analyzed for nitrogen (N) concentration. Oven drying increased (P < 0.05) fiber concentrations with some species, but not with others. For high-CT forage and browse species, ADFSEP concentrations were greater (P < 0.05) than NDFom values and approximately double the ADFSEQ values. Nitrogen concentration was greater (P < 0.05) in ADFSEP than ADFSEQ residues, likely due to precipitation with CTs. Sequential NDF-ADF analysis gave more realistic values and appeared to remove most of the fiber residue contaminants in CT forage samples. Freeze drying samples with sequential NDF-ADF analysis is recommended in the ANKOM™ fiber analysis system with CT-containing forage and browse species. Copyright © 2010 Society of Chemical Industry.

  2. African Journals Online: Browse Alphabetically -- letter T

    African Journals Online (AJOL)

    Items 1 - 19 of 19 ... African Journals Online: Browse Alphabetically -- letter T ... and economic aspects of management and conservation of tropical flora and fauna. ... Les principaux thèmes qui y sont abordés recouvrent les axes de recherche ...

  3. Tile-Level Annotation of Satellite Images Using Multi-Level Max-Margin Discriminative Random Field

    Directory of Open Access Journals (Sweden)

    Hong Sun

    2013-05-01

    Full Text Available This paper proposes a multi-level max-margin discriminative analysis (M3DA framework, which takes both coarse and fine semantics into consideration, for the annotation of high-resolution satellite images. In order to generate more discriminative topic-level features, the M3DA uses the maximum entropy discrimination latent Dirichlet Allocation (MedLDA model. Moreover, for improving the spatial coherence of visual words neglected by M3DA, conditional random field (CRF is employed to optimize the soft label field composed of multiple label posteriors. The framework of M3DA enables one to combine word-level features (generated by support vector machines and topic-level features (generated by MedLDA via the bag-of-words representation. The experimental results on high-resolution satellite images have demonstrated that, using the proposed method can not only obtain suitable semantic interpretation, but also improve the annotation performance by taking into account the multi-level semantics and the contextual information.

  4. Browsing while reading: effects of instructional design and learners' prior knowledge

    Directory of Open Access Journals (Sweden)

    Theimo Müller-Kalthoff

    2006-12-01

    Full Text Available One of the key reasons that multimedia, and particularly hypertext systems, are gaining in importance is that they inspire hopes of optimizing learners' processes of knowledge construction. The present study is concerned with the respective influence of individual learner variables (i.e. particularly domain-specific prior knowledge on the use of different design attributes. Thirty-six university students worked through a hierarchically structured two-part hypertext about the psychology of memory under two experimental browsing conditions (reduced versus free browsing. Results show that deeper-level comprehension (i.e. structural knowledge was predicted by the interaction of experimental condition and prior knowledge, but that simply retaining facts was not. Participants with low prior knowledge performed better on the comprehension test if they had worked on the version with reduced access. Moreover, the version with reduced access helped to reduce feelings of disorientation. The measure of disorientation also appeared to be closely linked with the individual's computer experience, self-concept of computer ability and subject-related interest. The main implications for educational practice relate to the design of an adaptive multimedia and hypertext learning system and the successful learning with it.

  5. Vertebrate Herbivore Browsing on Neighboring Forage Species Increases the Growth and Dominance of Siberian Alder Across a Latitudinal Transect in Northern Alaska.

    Science.gov (United States)

    McNeill, E. M.; Ruess, R. W.

    2017-12-01

    Vertebrate herbivores strongly influence plant growth and architecture, biogeochemical cycling, and successional dynamics in boreal and arctic ecosystems. One of the most notable impacts of vertebrate herbivory is on the growth and spread of alder, a chemically-defended, N-fixing shrub whose distribution in the Alaskan arctic has expanded dramatically over the past 60 years. Although herbivore effects on thin-leaf alder are well described for interior Alaskan floodplains, no work has been conducted on the effects of herbivores on Siberian alder (Alnus viridis spp fruticosa), despite the increasing importance of this species to high latitude ecosystems. We characterized browsing by snowshoe hares, moose, and willow ptarmigan on dominant shrub species across topo-edaphic sequences within 5 ecoregions along a 600 km latitudinal transect extending from interior Alaska to the North Slope. Ptarmigan browsed wind-blown lowland and alpine sites devoid of trees in all regions; moose browsed predominantly willow species in hardwood and mixed forests and were absent north of the Brooks Range; snowshoe hares selected habitats and forage based on their local density and vulnerability to predators. Browsing intensity on Siberian alder was either undetectable or low, limited primarily to hare browsing on young ramets in the northern boreal forest where hare density relative to forage availability is highest. Overall, alder height growth was positively correlated with levels of herbivory on competing shrub species. Our data support the hypothesis that vertebrate herbivore browsing is indirectly augmenting the growth, dominance, and possible spread of Siberian alder throughout its northern Alaskan range. Given the potential high rates of N-fixation inputs by Siberian alder, we believe herbivores are also having strong indirect effects on biogeochemical cycling and possibly C storage in these landscapes.

  6. Non-visual Web Browsing: Beyond Web Accessibility.

    Science.gov (United States)

    Ramakrishnan, I V; Ashok, Vikas; Billah, Syed Masum

    2017-07-01

    People with vision impairments typically use screen readers to browse the Web. To facilitate non-visual browsing, web sites must be made accessible to screen readers, i.e., all the visible elements in the web site must be readable by the screen reader. But even if web sites are accessible, screen-reader users may not find them easy to use and/or easy to navigate. For example, they may not be able to locate the desired information without having to listen to a lot of irrelevant contents. These issues go beyond web accessibility and directly impact web usability. Several techniques have been reported in the accessibility literature for making the Web usable for screen reading. This paper is a review of these techniques. Interestingly, the review reveals that understanding the semantics of the web content is the overarching theme that drives these techniques for improving web usability.

  7. County-Level Population Economic Status and Medicare Imaging Resource Consumption.

    Science.gov (United States)

    Rosenkrantz, Andrew B; Hughes, Danny R; Prabhakar, Anand M; Duszak, Richard

    2017-06-01

    The aim of this study was to assess relationships between county-level variation in Medicare beneficiary imaging resource consumption and measures of population economic status. The 2013 CMS Geographic Variation Public Use File was used to identify county-level per capita Medicare fee-for-service imaging utilization and nationally standardized costs to the Medicare program. The County Health Rankings public data set was used to identify county-level measures of population economic status. Regional variation was assessed, and multivariate regressions were performed. Imaging events per 1,000 Medicare beneficiaries varied 1.8-fold (range, 2,723-4,843) at the state level and 5.3-fold (range, 1,228-6,455) at the county level. Per capita nationally standardized imaging costs to Medicare varied 4.2-fold (range, $84-$353) at the state level and 14.1-fold (range, $33-$471) at the county level. Within individual states, county-level utilization varied on average 2.0-fold (range, 1.1- to 3.1-fold), and costs varied 2.8-fold (range, 1.1- to 6.4-fold). For both large urban populations and small rural states, Medicare imaging resource consumption was heterogeneously variable at the county level. Adjusting for county-level gender, ethnicity, rural status, and population density, countywide unemployment rates showed strong independent positive associations with Medicare imaging events (β = 26.96) and costs (β = 4.37), whereas uninsured rates showed strong independent positive associations with Medicare imaging costs (β = 2.68). Medicare imaging utilization and costs both vary far more at the county than at the state level. Unfavorable measures of county-level population economic status in the non-Medicare population are independently associated with greater Medicare imaging resource consumption. Future efforts to optimize Medicare imaging use should consider the influence of local indigenous socioeconomic factors outside the scope of traditional beneficiary-focused policy

  8. The Criteria People Use in Relevance Decisions on Health Information: An Analysis of User Eye Movements When Browsing a Health Discussion Forum.

    Science.gov (United States)

    Pian, Wenjing; Khoo, Christopher Sg; Chang, Yun-Ke

    2016-06-20

    People are increasingly accessing health-related social media sites, such as health discussion forums, to post and read user-generated health information. It is important to know what criteria people use when deciding the relevance of information found on health social media websites, in different situations. The study attempted to identify the relevance criteria that people use when browsing a health discussion forum, in 3 types of use contexts: when seeking information for their own health issue, when seeking for other people's health issue, and when browsing without a particular health issue in mind. A total of 58 study participants were self-assigned to 1 of the 3 use contexts or information needs and were asked to browse a health discussion forum, HealthBoards.com. In the analysis, browsing a discussion forum was divided into 2 stages: scanning a set of post surrogates (mainly post titles) in the summary result screen and reading a detailed post content (including comments by other users). An eye tracker system was used to capture participants' eye movement behavior and the text they skim over and focus (ie, fixate) on during browsing. By analyzing the text that people's eyes fixated on, the types of health information used in the relevance judgment were determined. Post-experiment interviews elicited participants' comments on the relevance of the information and criteria used. It was found that participants seeking health information for their own health issue focused significantly more on the poster's symptoms, personal history of the disease, and description of the disease (P=.01, .001, and .02). Participants seeking for other people's health issue focused significantly more on cause of disease, disease terminology, and description of treatments and procedures (P=.01, .01, and .02). In contrast, participants browsing with no particular issue in mind focused significantly more on general health topics, hot topics, and rare health issues (P=.01, .01, and .01

  9. The Criteria People Use in Relevance Decisions on Health Information: An Analysis of User Eye Movements When Browsing a Health Discussion Forum

    Science.gov (United States)

    Khoo, Christopher SG; Chang, Yun-Ke

    2016-01-01

    Background People are increasingly accessing health-related social media sites, such as health discussion forums, to post and read user-generated health information. It is important to know what criteria people use when deciding the relevance of information found on health social media websites, in different situations. Objective The study attempted to identify the relevance criteria that people use when browsing a health discussion forum, in 3 types of use contexts: when seeking information for their own health issue, when seeking for other people’s health issue, and when browsing without a particular health issue in mind. Methods A total of 58 study participants were self-assigned to 1 of the 3 use contexts or information needs and were asked to browse a health discussion forum, HealthBoards.com. In the analysis, browsing a discussion forum was divided into 2 stages: scanning a set of post surrogates (mainly post titles) in the summary result screen and reading a detailed post content (including comments by other users). An eye tracker system was used to capture participants’ eye movement behavior and the text they skim over and focus (ie, fixate) on during browsing. By analyzing the text that people’s eyes fixated on, the types of health information used in the relevance judgment were determined. Post-experiment interviews elicited participants’ comments on the relevance of the information and criteria used. Results It was found that participants seeking health information for their own health issue focused significantly more on the poster’s symptoms, personal history of the disease, and description of the disease (P=.01, .001, and .02). Participants seeking for other people’s health issue focused significantly more on cause of disease, disease terminology, and description of treatments and procedures (P=.01, .01, and .02). In contrast, participants browsing with no particular issue in mind focused significantly more on general health topics, hot

  10. 3D-LSI technology for image sensor

    International Nuclear Information System (INIS)

    Motoyoshi, Makoto; Koyanagi, Mitsumasa

    2009-01-01

    Recently, the development of three-dimensional large-scale integration (3D-LSI) technologies has accelerated and has advanced from the research level or the limited production level to the investigation level, which might lead to mass production. By separating 3D-LSI technology into elementary technologies such as (1) through silicon via (TSV) formation, (2) bump formation, (3) wafer thinning, (4) chip/wafer alignment, and (5) chip/wafer stacking and reconstructing the entire process and structure, many methods to realize 3D-LSI devices can be developed. However, by considering a specific application, the supply chain of base wafers, and the purpose of 3D integration, a few suitable combinations can be identified. In this paper, we focus on the application of 3D-LSI technologies to image sensors. We describe the process and structure of the chip size package (CSP), developed on the basis of current and advanced 3D-LSI technologies, to be used in CMOS image sensors. Using the current LSI technologies, CSPs for 1.3 M, 2 M, and 5 M pixel CMOS image sensors were successfully fabricated without any performance degradation. 3D-LSI devices can be potentially employed in high-performance focal-plane-array image sensors. We propose a high-speed image sensor with an optical fill factor of 100% to be developed using next-generation 3D-LSI technology and fabricated using micro(μ)-bumps and micro(μ)-TSVs.

  11. Medical Applications of Remote Electronic Browsing.

    Science.gov (United States)

    Chadwick, Joseph

    The purposes of this study are to identify and define viable remote browsing techniques and the requirements for an interactive medical information system that would permit the use of such techniques. The main emphasis is in the areas of: (1) remote viewing of page material; and (2) remote interrogation of fact banks with question-answering…

  12. Building a SuAVE browse interface to R2R's Linked Data

    Science.gov (United States)

    Clark, D.; Stocks, K. I.; Arko, R. A.; Zaslavsky, I.; Whitenack, T.

    2017-12-01

    The Rolling Deck to Repository program (R2R) is creating and evaluating a new browse portal based on the SuAVE platform and the R2R linked data graph. R2R manages the underway sensor data collected by the fleet of US academic research vessels, and provides a discovery and access point to those data at its website, www.rvdata.us. R2R has a database-driven search interface, but seeks a more capable and extensible browse interface that could be built off of the substantial R2R linked data resources. R2R's Linked Data graph organizes its data holdings around key concepts (e.g. cruise, vessel, device type, operator, award, organization, publication), anchored by persistent identifiers where feasible. The "Survey Analysis via Visual Exploration" or SuAVE platform (suave.sdsc.edu) is a system for online publication, sharing, and analysis of images and metadata. It has been implemented as an interface to diverse data collections, but has not been driven off of linked data in the past. SuAVE supports several features of interest to R2R, including faceted searching, collaborative annotations, efficient subsetting, Google maps-like navigation over an image gallery, and several types of data analysis. Our initial SuAVE-based implementation was through a CSV export from the R2R PostGIS-enabled PostgreSQL database. This served to demonstrate the utility of SuAVE but was static and required reloading as R2R data holdings grew. We are now working to implement a SPARQL-based ("RDF Query Language") service that directly leverages the R2R Linked Data graph and offers the ability to subset and/or customize output.We will show examples of SuAVE faceted searches on R2R linked data concepts, and discuss our experience to date with this work in progress.

  13. Distance between images

    Science.gov (United States)

    Gualtieri, J. A.; Le Moigne, J.; Packer, C. V.

    1992-01-01

    Comparing two binary images and assigning a quantitative measure to this comparison finds its purpose in such tasks as image recognition, image compression, and image browsing. This quantitative measurement may be computed by utilizing the Hausdorff distance of the images represented as two-dimensional point sets. In this paper, we review two algorithms that have been proposed to compute this distance, and we present a parallel implementation of one of them on the MasPar parallel processor. We study their complexity and the results obtained by these algorithms for two different types of images: a set of displaced pairs of images of Gaussian densities, and a comparison of a Canny edge image with several edge images from a hierarchical region growing code.

  14. Deer browsing delays succession by altering aboveground vegetation and belowground seed banks.

    Directory of Open Access Journals (Sweden)

    Antonio DiTommaso

    Full Text Available Soil seed bank composition is important to the recovery of natural and semi-natural areas from disturbance and serves as a safeguard against environmental catastrophe. White-tailed deer (Odocoileus virginianus populations have increased dramatically in eastern North America over the past century and can have strong impacts on aboveground vegetation, but their impacts on seed bank dynamics are less known. To document the long-term effects of deer browsing on plant successional dynamics, we studied the impacts of deer on both aboveground vegetation and seed bank composition in plant communities following agricultural abandonment. In 2005, we established six 15 × 15 m fenced enclosures and paired open plots in recently followed agricultural fields near Ithaca, NY, USA. In late October of each of six years (2005-2010, we collected soil from each plot and conducted seed germination cycles in a greenhouse to document seed bank composition. These data were compared to measurements of aboveground plant cover (2005-2008 and tree density (2005-2012. The impacts of deer browsing on aboveground vegetation were severe and immediate, resulting in significantly more bare soil, reduced plant biomass, reduced recruitment of woody species, and relatively fewer native species. These impacts persisted throughout the experiment. The impacts of browsing were even stronger on seed bank dynamics. Browsing resulted in significantly decreased overall species richness (but higher diversity, reduced seed bank abundance, relatively more short-lived species (annuals and biennials, and fewer native species. Both seed bank richness and the relative abundance of annuals/biennials were mirrored in the aboveground vegetation. Thus, deer browsing has long-term and potentially reinforcing impacts on secondary succession, slowing succession by selectively consuming native perennials and woody species and favoring the persistence of short-lived, introduced species that continually

  15. Browsing software of the Visible Korean data used for teaching sectional anatomy.

    Science.gov (United States)

    Shin, Dong Sun; Chung, Min Suk; Park, Hyo Seok; Park, Jin Seo; Hwang, Sung Bae

    2011-01-01

    The interpretation of computed tomographs (CTs) and magnetic resonance images (MRIs) to diagnose clinical conditions requires basic knowledge of sectional anatomy. Sectional anatomy has traditionally been taught using sectioned cadavers, atlases, and/or computer software. The computer software commonly used for this subject is practical and efficient for students but could be more advanced. The objective of this research was to present browsing software developed from the Visible Korean images that can be used for teaching sectional anatomy. One thousand seven hundred and two sets of MRIs, CTs, and sectioned images (intervals, one millimeter) of a whole male cadaver were prepared. Over 900 structures in the sectioned images were outlined and then filled with different colors to elaborate each structure. Software was developed where four corresponding images could be displayed simultaneously; in addition, the structures in the image data could be readily recognized with the aid of the color-filled outlines. The software, distributed free of charge, could be a valuable tool to teach medical students. For example, sectional anatomy could be taught by showing the sectioned images with real color and high resolution. Students could then review the lecture by using the sectioned and color-filled images on their own computers. Students could also be evaluated using the same software. Furthermore, other investigators would be able to replace the images for more comprehensive sectional anatomy. Copyright © 2011 Wiley-Liss, Inc.

  16. MODIS Level-3 Standard Mapped Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  17. Ontology-based image navigation: exploring 3.0-T MR neurography of the brachial plexus using AIM and RadLex.

    Science.gov (United States)

    Wang, Kenneth C; Salunkhe, Aditya R; Morrison, James J; Lee, Pearlene P; Mejino, José L V; Detwiler, Landon T; Brinkley, James F; Siegel, Eliot L; Rubin, Daniel L; Carrino, John A

    2015-01-01

    Disorders of the peripheral nervous system have traditionally been evaluated using clinical history, physical examination, and electrodiagnostic testing. In selected cases, imaging modalities such as magnetic resonance (MR) neurography may help further localize or characterize abnormalities associated with peripheral neuropathies, and the clinical importance of such techniques is increasing. However, MR image interpretation with respect to peripheral nerve anatomy and disease often presents a diagnostic challenge because the relevant knowledge base remains relatively specialized. Using the radiology knowledge resource RadLex®, a series of RadLex queries, the Annotation and Image Markup standard for image annotation, and a Web services-based software architecture, the authors developed an application that allows ontology-assisted image navigation. The application provides an image browsing interface, allowing users to visually inspect the imaging appearance of anatomic structures. By interacting directly with the images, users can access additional structure-related information that is derived from RadLex (eg, muscle innervation, muscle attachment sites). These data also serve as conceptual links to navigate from one portion of the imaging atlas to another. With 3.0-T MR neurography of the brachial plexus as the initial area of interest, the resulting application provides support to radiologists in the image interpretation process by allowing efficient exploration of the MR imaging appearance of relevant nerve segments, muscles, bone structures, vascular landmarks, anatomic spaces, and entrapment sites, and the investigation of neuromuscular relationships. RSNA, 2015

  18. Browses (legume-legume mixture) as dry season feed ...

    African Journals Online (AJOL)

    Increasing competition between man and animals(monogasters, polygasters, microlivestock and wild/feral) for high quality feed(proteinaceous and carbonaceous concentrate) excessive pressure on land from urbanisation , hence the need of multipurpose browse-legumes (Leucaena leucocephala, Gliricidia sepium and ...

  19. Subband coding for image data archiving

    Science.gov (United States)

    Glover, Daniel; Kwatra, S. C.

    1993-01-01

    The use of subband coding on image data is discussed. An overview of subband coding is given. Advantages of subbanding for browsing and progressive resolution are presented. Implementations for lossless and lossy coding are discussed. Algorithm considerations and simple implementations of subband systems are given.

  20. apART: system for the acquisition, processing, archiving, and retrieval of digital images in an open, distributed imaging environment

    Science.gov (United States)

    Schneider, Uwe; Strack, Ruediger

    1992-04-01

    apART reflects the structure of an open, distributed environment. According to the general trend in the area of imaging, network-capable, general purpose workstations with capabilities of open system image communication and image input are used. Several heterogeneous components like CCD cameras, slide scanners, and image archives can be accessed. The system is driven by an object-oriented user interface where devices (image sources and destinations), operators (derived from a commercial image processing library), and images (of different data types) are managed and presented uniformly to the user. Browsing mechanisms are used to traverse devices, operators, and images. An audit trail mechanism is offered to record interactive operations on low-resolution image derivatives. These operations are processed off-line on the original image. Thus, the processing of extremely high-resolution raster images is possible, and the performance of resolution dependent operations is enhanced significantly during interaction. An object-oriented database system (APRIL), which can be browsed, is integrated into the system. Attribute retrieval is supported by the user interface. Other essential features of the system include: implementation on top of the X Window System (X11R4) and the OSF/Motif widget set; a SUN4 general purpose workstation, inclusive ethernet, magneto optical disc, etc., as the hardware platform for the user interface; complete graphical-interactive parametrization of all operators; support of different image interchange formats (GIF, TIFF, IIF, etc.); consideration of current IPI standard activities within ISO/IEC for further refinement and extensions.

  1. Classification and interdisciplinary browsing: the experience at the University of Pavia

    Directory of Open Access Journals (Sweden)

    Laura Pusterla

    2017-05-01

    Full Text Available The gradual adoption by the University of Pavia libraries of the classified shelving based on the Dewey Decimal Classification is presented. This has allowed developing the browsing interface  SciGator, which offers the possibility to browse through the subjects in the libraries and launch searches in the OPAC catalogue for documents shelved by their corresponding DDC classes or their local equivalents. SciGator also allows searching for documents indexed with their respective class or with a class linked to it in the network of class cross-references. The convenience and possible improvements of SciGator are discussed.

  2. Digital Radiology Image Learning Library

    International Nuclear Information System (INIS)

    Arenson, R.L.; Greenes, R.; Allman, R.; Swett, H.

    1989-01-01

    The Digital Radiology Image Learning Library (DRILL) is designed as an interactive teaching tool targeted to the radiologic community. The DRILL pilot comprises a comprehensive mammographic information base consisting of factual data in a relational database, an extensive knowledge base in semantic nets and high-resolution images. A flexible query module permits the user to browse and retrieve examination data, case discussions, and related images. Other applications, including expert systems, instructional programs, and skill building exercises, can be accessed through well-defined software constructs

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

  4. Evaluation of wild animals browsing preferences in forage resources

    Directory of Open Access Journals (Sweden)

    Giovanni Argenti

    2017-09-01

    Full Text Available Excessive presence of wild ungulates can produce negative effects on herbaceous crops or woody species, and to face this problem, habitat improvements are often performed to recreate suitable environments for a given animal species and to attract animals far from cultivated crops. A common example of these interventions is represented by grassland restoration and to evaluate the real animal preferences on restored forage resources a proper trial was established in a hilly area of Tuscany (central Italy, inside the historical Park of Pratolino, near Florence. The trial compared six different forage species or mixtures sown in plots: vegetal material was represented by two pure stands (Onobrychis viciifolia and Medicago sativa and four mixtures differing in number and kind of used species. Plots were utilised only by wild animals occurring in the area. Data collection consisted of botanical samples in each plot in different periods to obtain the percent presence of each species. At the same time, a visual estimation of animal intake on all occurring species was performed to obtain the browsing ratio of single species and overall defoliation rate for each species/mixture. Moreover, six camera traps were placed on the boundary of the experimental site to record videos of wild animals browsing in the area for identification of animals actually occurring on different plots and for comparison of these results with botanical data. Vegetation surveys permitted a proper evaluation of animals intake and of their feeding preferences. In general, sown species performed a major role in animal browsing, even if in some periods also a few native species (such as Plantago lanceolata or Cichorium intybus were utilised in a strong way, depending on vegetation context and existing biomass. Camera traps results permitted the identification of browsing animal species (mainly represented by roe deer and plots frequentation resulted to be highly related to animal

  5. A Storyboard-Based Interface for Mobile Video Browsing

    NARCIS (Netherlands)

    Hürst, Wolfgang|info:eu-repo/dai/nl/313710589; Hoet, Miklas; van de Werken, Rob

    2015-01-01

    We present an interface design for video browsing on mobile devices such as tablets that is based on storyboards and optimized with respect to content visualization and interaction design. In particular, we consider scientific results from our previous studies on mobile visualization (e.g., about

  6. Current and future trends in marine image annotation software

    Science.gov (United States)

    Gomes-Pereira, Jose Nuno; Auger, Vincent; Beisiegel, Kolja; Benjamin, Robert; Bergmann, Melanie; Bowden, David; Buhl-Mortensen, Pal; De Leo, Fabio C.; Dionísio, Gisela; Durden, Jennifer M.; Edwards, Luke; Friedman, Ariell; Greinert, Jens; Jacobsen-Stout, Nancy; Lerner, Steve; Leslie, Murray; Nattkemper, Tim W.; Sameoto, Jessica A.; Schoening, Timm; Schouten, Ronald; Seager, James; Singh, Hanumant; Soubigou, Olivier; Tojeira, Inês; van den Beld, Inge; Dias, Frederico; Tempera, Fernando; Santos, Ricardo S.

    2016-12-01

    Given the need to describe, analyze and index large quantities of marine imagery data for exploration and monitoring activities, a range of specialized image annotation tools have been developed worldwide. Image annotation - the process of transposing objects or events represented in a video or still image to the semantic level, may involve human interactions and computer-assisted solutions. Marine image annotation software (MIAS) have enabled over 500 publications to date. We review the functioning, application trends and developments, by comparing general and advanced features of 23 different tools utilized in underwater image analysis. MIAS requiring human input are basically a graphical user interface, with a video player or image browser that recognizes a specific time code or image code, allowing to log events in a time-stamped (and/or geo-referenced) manner. MIAS differ from similar software by the capability of integrating data associated to video collection, the most simple being the position coordinates of the video recording platform. MIAS have three main characteristics: annotating events in real time, posteriorly to annotation and interact with a database. These range from simple annotation interfaces, to full onboard data management systems, with a variety of toolboxes. Advanced packages allow to input and display data from multiple sensors or multiple annotators via intranet or internet. Posterior human-mediated annotation often include tools for data display and image analysis, e.g. length, area, image segmentation, point count; and in a few cases the possibility of browsing and editing previous dive logs or to analyze the annotations. The interaction with a database allows the automatic integration of annotations from different surveys, repeated annotation and collaborative annotation of shared datasets, browsing and querying of data. Progress in the field of automated annotation is mostly in post processing, for stable platforms or still images

  7. enhancing adaptive utilization of browse trees for improved livestock

    African Journals Online (AJOL)

    CHIBINGA

    21 tree browse species identified by the agro-pastoralists, 18 species were found to be important during droughts and 8 ..... Firewood, charcoal, timber, food, bee forage. 13. Mukuyu. Ficus sur. Fruits. Food. 14 ... Dombeya rotundifolia. Leaves.

  8. Growth patterns of deer-browse plants in southern forests

    Science.gov (United States)

    Lowell K. Halls; R. Alcaniz

    1972-01-01

    Among plants of 16 browse species common in east Texas, the combination that would furnish succulent green forage earliest in spring and latest in fall includes yellow jessamine, Alabama supplejack, yaupon, rusty blackhaw, and flowering dogwood.

  9. DOBBS: Towards a Comprehensive Dataset to Study the Browsing Behavior of Online Users

    OpenAIRE

    von der Weth, Christian; Hauswirth, Manfred

    2013-01-01

    The investigation of the browsing behavior of users provides useful information to optimize web site design, web browser design, search engines offerings, and online advertisement. This has been a topic of active research since the Web started and a large body of work exists. However, new online services as well as advances in Web and mobile technologies clearly changed the meaning behind "browsing the Web" and require a fresh look at the problem and research, specifically in respect to wheth...

  10. Ungulate browsing maintains shrub diversity in the absence of episodic disturbance in seasonally-arid conifer forest

    Science.gov (United States)

    Burak K. Pekin; Michael J. Wisdom; Bryan A. Endress; Bridgett J. Naylor; Catherine G. Parks

    2014-01-01

    Ungulates exert a strong influence on the composition and diversity of vegetation communities. However, little is known about how ungulate browsing pressure interacts with episodic disturbances such as fire and stand thinning. We assessed shrub responses to variable browsing pressure by cattle and elk in fuels treated (mechanical removal of fuels followed by prescribed...

  11. The Costs of Web Advertisements while Mobile Browsing

    NARCIS (Netherlands)

    van den Brande, Jeffrey; Pras, Aiko

    Tablet PCs, iPads and mobile phones all include facilities to browse the mobile Internet. The costs of mobile Internet access may become extraordinary, however, when the data limit is exceeded or when the user is roaming abroad without a roaming data plan. Since users may see advertisements as

  12. Analysing Parallel and Passive Web Browsing Behavior and its Effects on Website Metrics

    OpenAIRE

    von der Weth, Christian; Hauswirth, Manfred

    2014-01-01

    Getting deeper insights into the online browsing behavior of Web users has been a major research topic since the advent of the WWW. It provides useful information to optimize website design, Web browser design, search engines offerings, and online advertisement. We argue that new technologies and new services continue to have significant effects on the way how people browse the Web. For example, listening to music clips on YouTube or to a radio station on Last.fm does not require users to sit...

  13. Fluid-fluid level on MR image: significance in Musculoskeletal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hye Won; Lee, Kyung Won [Seoul Naitonal University, Seoul (Korea, Republic of). Coll. of Medicine; Song, Chi Sung [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Han, Sang Wook; Kang, Heung Sik [Seoul Naitonal University, Seoul (Korea, Republic of). Coll. of Medicine

    1998-01-01

    To evaluate the frequency, number and signal intensity of fluid-fluid levels of musculoskeletal diseases on MR images, and to determine the usefulness of this information for the differentiation of musculoskeletal diseases. MR images revealed fluid-fluid levels in the following diseases : giant cell tumor(6), telangiectatic osteosarcoma(4), aneurysmal bone cyst(3), synovial sarcoma(3), chondroblastoma(2), soft tissue tuberculous abscess(2), hematoma(2), hemangioma (1), neurilemmoma(1), metastasis(1), malignant fibrous histiocytoma(1), bursitis(1), pyogenic abscess(1), and epidermoid inclusion cyst(1). Fourteen benign tumors and ten malignant, three abscesses, and the epidermoid inclusion cyst showed only one fluid-fluid level in a unilocular cyst. On T1-weighted images, the signal intensities of fluid varied, but on T2-weighted images, superior layers were in most cases more hyperintense than inferior layers. Because fluid-fluid layers are a nonspecific finding, it is difficult to specifically diagnose each disease according to the number of fluid-fluid levels or signal intensity of fluid. In spite of the nonspecificity of fluid-fluid levels, they were frequently seen in cases of giant cell tumor, telangiectatic osteosarcoma, aneurysmal bone cycle, and synovial sarcoma. Nontumorous diseases such abscesses and hematomas also demonstrated this finding. (author). 11 refs., 1 tab., 4 figs.

  14. Fluid-fluid level on MR image: significance in Musculoskeletal diseases

    International Nuclear Information System (INIS)

    Chung, Hye Won; Lee, Kyung Won; Han, Sang Wook; Kang, Heung Sik

    1998-01-01

    To evaluate the frequency, number and signal intensity of fluid-fluid levels of musculoskeletal diseases on MR images, and to determine the usefulness of this information for the differentiation of musculoskeletal diseases. MR images revealed fluid-fluid levels in the following diseases : giant cell tumor(6), telangiectatic osteosarcoma(4), aneurysmal bone cyst(3), synovial sarcoma(3), chondroblastoma(2), soft tissue tuberculous abscess(2), hematoma(2), hemangioma (1), neurilemmoma(1), metastasis(1), malignant fibrous histiocytoma(1), bursitis(1), pyogenic abscess(1), and epidermoid inclusion cyst(1). Fourteen benign tumors and ten malignant, three abscesses, and the epidermoid inclusion cyst showed only one fluid-fluid level in a unilocular cyst. On T1-weighted images, the signal intensities of fluid varied, but on T2-weighted images, superior layers were in most cases more hyperintense than inferior layers. Because fluid-fluid layers are a nonspecific finding, it is difficult to specifically diagnose each disease according to the number of fluid-fluid levels or signal intensity of fluid. In spite of the nonspecificity of fluid-fluid levels, they were frequently seen in cases of giant cell tumor, telangiectatic osteosarcoma, aneurysmal bone cycle, and synovial sarcoma. Nontumorous diseases such abscesses and hematomas also demonstrated this finding. (author). 11 refs., 1 tab., 4 figs

  15. Federating resources of information systems: browsing interface (FRISBI)

    NARCIS (Netherlands)

    Malchanau, A.V.; van der Vet, P.E.; Roosendaal, Hans E.; de Bra, P.M.E.

    2003-01-01

    Designing the user interface of a federated system (what we call a browsing interface) must consider the knowledge gap that exists between desires of the users and the needs the systems are built to support. The concept of Habitable Interfaces aims to bridge the knowledge gap by providing kinds of

  16. Diagnostic reference levels in medical imaging

    International Nuclear Information System (INIS)

    Rosenstein, M.

    2001-01-01

    The paper proposes additional advice to national or local authorities and the clinical community on the application of diagnostic reference levels as a practical tool to manage radiation doses to patients in diagnostic radiology and nuclear medicine. A survey was made of the various approaches that have been taken by authoritative bodies to establish diagnostic reference levels for medical imaging tasks. There are a variety of ways to implement the idea of diagnostic reference levels, depending on the medical imaging task of interest, the national or local state of practice and the national or local preferences for technical implementation. The existing International Commission on Radiological Protection (ICRP) guidance is reviewed, the survey information is summarized, a set of unifying principles is espoused and a statement of additional advice that has been proposed to ICRP Committee 3 is presented. The proposed advice would meet a need for a unifying set of principles to provide a framework for diagnostic reference levels but would allow flexibility in their selection and use. While some illustrative examples are given, the proposed advice does not specify the specific quantities to be used, the numerical values to be set for the quantities or the technical details of how national or local authorities should implement diagnostic reference levels. (author)

  17. The Impact of Different Levels of Adaptive Iterative Dose Reduction 3D on Image Quality of 320-Row Coronary CT Angiography: A Clinical Trial.

    Directory of Open Access Journals (Sweden)

    Sarah Feger

    Full Text Available The aim of this study was the systematic image quality evaluation of coronary CT angiography (CTA, reconstructed with the 3 different levels of adaptive iterative dose reduction (AIDR 3D and compared to filtered back projection (FBP with quantum denoising software (QDS.Standard-dose CTA raw data of 30 patients with mean radiation dose of 3.2 ± 2.6 mSv were reconstructed using AIDR 3D mild, standard, strong and compared to FBP/QDS. Objective image quality comparison (signal, noise, signal-to-noise ratio (SNR, contrast-to-noise ratio (CNR, contour sharpness was performed using 21 measurement points per patient, including measurements in each coronary artery from proximal to distal.Objective image quality parameters improved with increasing levels of AIDR 3D. Noise was lowest in AIDR 3D strong (p ≤ 0.001 at 20/21 measurement points; compared with FBP/QDS. Signal and contour sharpness analysis showed no significant difference between the reconstruction algorithms for most measurement points. Best coronary SNR and CNR were achieved with AIDR 3D strong. No loss of SNR or CNR in distal segments was seen with AIDR 3D as compared to FBP.On standard-dose coronary CTA images, AIDR 3D strong showed higher objective image quality than FBP/QDS without reducing contour sharpness.Clinicaltrials.gov NCT00967876.

  18. SHRIMP (CRANGON-CRANGON L) BROWSING UPON SIPHON TIPS INHIBITS FEEDING AND GROWTH IN THE BIVALVE MACOMA-BALTHICA (L)

    NARCIS (Netherlands)

    KAMERMANS, P; HUITEMA, HJ

    1994-01-01

    The influence of siphon browsing on the feeding behaviour and growth of Macoma balthica, a deposit-feeding bivalve, was studied in three manipulative experiments. Browsing was simulated by removing part of the inhalant siphon with scissors, or studied by exposing the bivalves to shrimps (Crangon

  19. Communication and Reception in Teaching: The Age of Image "versus" the "Weight" of Words

    Science.gov (United States)

    Bradea, Adela

    2015-01-01

    Contemporary culture is mainly a culture of image. We get our information seeing. Examination of images is free, while reading is impelled by the necessity of browsing the whole text. The image seems more appropriate than the text when trying to communicate easy and quickly. The speech calls for articulated language, expressed through a symbolic…

  20. Storyboard-Based Video Browsing Using Color and Concept Indices

    NARCIS (Netherlands)

    Hürst, W.O.; Ip Vai Ching, Algernon; Schoeffmann, K.; Primus, Manfred J.

    2017-01-01

    We present an interface for interactive video browsing where users visually skim storyboard representations of the files in search for known items (known-item search tasks) and textually described subjects, objects, or events (ad-hoc search tasks). Individual segments of the video are represented as

  1. Nutritional composition and condensed tannin concentration changes as browse leaves become litter.

    Science.gov (United States)

    Acero, Amanda; Muir, James P; Wolfe, Richard M

    2010-12-01

    The role of condensed tannins (CT) in ruminant nutrition and health makes changes in leaf litter (LL) after abscission of interest. This study compared the effect of different drying methods of green leaves (GL) with that of natural drying of LL on CT, fibre, crude protein (CP) and phosphorus (P) concentrations in nine Texas browse species. Leaves harvested before autumn shedding were oven-dried (OD) or freeze-dried (FD). Where different (P Drying method changed total CT concentration in three species. Where different, fibre fraction concentrations were greater in LL than in GL, regardless of drying method. In some species, CP and P concentrations were lower in LL than in GL, but in five species they did not change (P > 0.05) from GL to LL, with CP concentrations ranging from 63 to 151 g kg(-1) in the latter. Browse LL had high nutritive value and CT concentrations, explaining why browsing ruminants utilise this feed resource. However, changes in nutrient and CT concentrations as leaves become litter in some species mean that information on one is not necessarily applicable to the other. Copyright © 2010 Society of Chemical Industry.

  2. How happy is your web browsing? A model to quantify satisfaction of an Internet user searching for desired information

    Science.gov (United States)

    Banerji, Anirban; Magarkar, Aniket

    2012-09-01

    We feel happy when web browsing operations provide us with necessary information; otherwise, we feel bitter. How to measure this happiness (or bitterness)? How does the profile of happiness grow and decay during the course of web browsing? We propose a probabilistic framework that models the evolution of user satisfaction, on top of his/her continuous frustration at not finding the required information. It is found that the cumulative satisfaction profile of a web-searching individual can be modeled effectively as the sum of a random number of random terms, where each term is a mutually independent random variable, originating from ‘memoryless’ Poisson flow. Evolution of satisfaction over the entire time interval of a user’s browsing was modeled using auto-correlation analysis. A utilitarian marker, a magnitude of greater than unity of which describes happy web-searching operations, and an empirical limit that connects user’s satisfaction with his frustration level-are proposed too. The presence of pertinent information in the very first page of a website and magnitude of the decay parameter of user satisfaction (frustration, irritation etc.) are found to be two key aspects that dominate the web user’s psychology. The proposed model employed different combinations of decay parameter, searching time and number of helpful websites. The obtained results are found to match the results from three real-life case studies.

  3. Browsing affects intra-ring carbon allocation in species with contrasting wood anatomy.

    Science.gov (United States)

    Palacio, S; Paterson, E; Sim, A; Hester, A J; Millard, P

    2011-02-01

    Current knowledge on tree carbon (C) allocation to wood is particularly scarce in plants subjected to disturbance factors, such as browsing, which affects forest regeneration worldwide and has an impact on the C balance of trees. Furthermore, quantifying the degree to which tree rings are formed from freshly assimilated vs. stored carbohydrates is highly relevant for our understanding of tree C allocation. We used (13)C labelling to quantify seasonal allocation of stored C to wood formation in two species with contrasting wood anatomy: Betula pubescens Ehrh. (diffuse-porous) and Quercus petraea [Matt.] Liebl. (ring-porous). Clipping treatments (66% shoot removal, and unclipped) were applied to analyse the effect of browsing on C allocation into tree rings, plus the effects on tree growth, architecture, ring width and non-structural carbohydrates (NSCs). The relative contribution of stored C to wood formation was greater in the ring-porous (55-70%) than in the diffuse-porous species (35-60%), although each species followed different seasonal trends. Clipping did not cause a significant depletion of C stores in either species. Nonetheless, a significant increase in the proportion of stored C allocated to earlywood growth was observed in clipped birches, and this could be explained through changes in tree architecture after clipping. The size of C pools across tree species seems to be important in determining the variability of seasonal C allocation patterns to wood and their sensibility to disturbances such as browsing. Our results indicate that the observed changes in C allocation to earlywood in birch were not related to variations in the amount or concentration of NSC stores, but to changes in the seasonal availability of recently assimilated C caused by modifications in tree architecture after browsing.

  4. Imaging the olfactory tract (Cranial Nerve no.1)

    International Nuclear Information System (INIS)

    Duprez, Thierry P.; Rombaux, Philippe

    2010-01-01

    This review paper browses pros and cons of the different radiological modalities for imaging the olfactory tract and highlights the potential benefits and limitation of more recent advances in MR and CT technology. A systematic pictorial overview of pathological conditions affecting olfactory sense is given. Techniques for collecting quantitative data on olfactory bulb volume and on olfactory sulcus depth are described. At last, insights into functional imaging of olfactory sense are shown.

  5. Making RDF Presentable - Integrated Global and Local Semantic Web Browsing

    NARCIS (Netherlands)

    L. Rutledge (Lloyd); J.R. van Ossenbruggen (Jacco); L. Hardman (Lynda)

    2005-01-01

    textabstractThis paper discusses generating document structure from annotated media repositories in a domain-independent manner. This approaches the vision of a universal RDF browser. We start by applying the search-and-browse paradigm established for the WWW to RDF presentation. Furthermore, this

  6. Making RDF presentable: integrated global and local semantic web browsing

    NARCIS (Netherlands)

    L. Rutledge (Lloyd); J.R. van Ossenbruggen (Jacco); L. Hardman (Lynda)

    2005-01-01

    textabstractThis paper discusses generating document structure from annotated media repositories in a domain-independent manner. This approaches the vision of a universal RDF browser. We start by applying the search-and-browse paradigm established for the WWW to RDF presentation. Furthermore, this

  7. DETECTING FORESTS DAMAGED BY PINE WILT DISEASE AT THE INDIVIDUAL TREE LEVEL USING AIRBORNE LASER DATA AND WORLDVIEW-2/3 IMAGES OVER TWO SEASONS

    Directory of Open Access Journals (Sweden)

    Y. Takenaka

    2017-10-01

    Full Text Available Pine wilt disease is caused by the pine wood nematode (Bursaphelenchus xylophilus and Japanese pine sawyer (Monochamus alternatus. This study attempted to detect damaged pine trees at different levels using a combination of airborne laser scanning (ALS data and high-resolution space-borne images. A canopy height model with a resolution of 50 cm derived from the ALS data was used for the delineation of tree crowns using the Individual Tree Detection method. Two pan-sharpened images were established using the ortho-rectified images. Next, we analyzed two kinds of intensity-hue-saturation (IHS images and 18 remote sensing indices (RSI derived from the pan-sharpened images. The mean and standard deviation of the 2 IHS images, 18 RSI, and 8 bands of the WV-2 and WV-3 images were extracted for each tree crown and were used to classify tree crowns using a support vector machine classifier. Individual tree crowns were assigned to one of nine classes: bare ground, Larix kaempferi, Cryptomeria japonica, Chamaecyparis obtusa, broadleaved trees, healthy pines, and damaged pines at slight, moderate, and heavy levels. The accuracy of the classifications using the WV-2 images ranged from 76.5 to 99.6 %, with an overall accuracy of 98.5 %. However, the accuracy of the classifications using the WV-3 images ranged from 40.4 to 95.4 %, with an overall accuracy of 72 %, which suggests poorer accuracy compared to those classes derived from the WV-2 images. This is because the WV-3 images were acquired in October 2016 from an area with low sun, at a low altitude.

  8. Browsing for Information on the Web and in the File System

    National Research Council Canada - National Science Library

    Seifert, Ethan; Stumpf, Simone; Herlocker, Jonathan; Wynn, Eleanor

    2007-01-01

    Browsing is one of the methods used for finding and refinding information on the web or in the file local system and there are opportunities to avoid this, particularly if that information is revisited frequently...

  9. Remote Sensing Forage Quality for Browsing Herbivores: A Case Study of Cutting Edge Koala Conservation

    Science.gov (United States)

    Youngentob, K. N.; Au, J.; Held, A. A.; Foley, W. J.; Possingham, H. P.

    2014-12-01

    Managing landscapes for conservation requires a capacity to measure habitat quality. Although multiple factors are often responsible for the distribution and abundance of herbivores, spatial variations in the quality and quantity of plant forage are known to be important for many species. While we cannot see the chemical complexity of landscapes with our naked-eye, advances in imaging spectroscopy are making it possible to assess the quality of forage on a landscape-scale. Much research in this area has focused on the ability to estimate foliar nitrogen (N), because N is believed to be a limiting nutrient for many leaf eating animals. However, the total quantity of foliar N does not necessarily reflect the amount of N that can be utilized by herbivores. Available nitrogen (AvailN) is an invitro measure of forage quality that integrates the influence of tannins and fibre on the amount of foliar N that is available for digestion by herbivores. This may be a more meaningful measure of forage quality than total N for the many herbivorous species that are sensitive to the effects of tannins. Our previous research has demonstrated that it is possible to estimate this integrated measure of foliar nutritional quality at an individual tree crown level across multiple tree species using imaging spectroscopy (HyMap). Here we present a case study of how this remote sensing data is being used to help inform landscape management and conservation decisions for an iconic Australian species, the koala (Phascolarctos cinereus). We review the methods involved in developing maps of integrated measures of foliar nutritional quality for browsing herbivores with airborne imaging spectroscopy data and discuss their applications for wildlife management.

  10. Making RDF presentable : integrated global and local semantic web browsing

    NARCIS (Netherlands)

    Rutledge, L.W.; Ossenbruggen, van J.R.; Hardman, H.L.

    2005-01-01

    This paper discusses generating document structure from annotated media repositories in a domain-independent manner. This approaches the vision of a universal RDF browser. We start by applying the search-and-browse paradigm established for the WWW to RDF presentation. Furthermore, this paper adds to

  11. Automatic extraction of soft tissues from 3D MRI head images using model driven analysis

    International Nuclear Information System (INIS)

    Jiang, Hao; Yamamoto, Shinji; Imao, Masanao.

    1995-01-01

    This paper presents an automatic extraction system (called TOPS-3D : Top Down Parallel Pattern Recognition System for 3D Images) of soft tissues from 3D MRI head images by using model driven analysis algorithm. As the construction of system TOPS we developed, two concepts have been considered in the design of system TOPS-3D. One is the system having a hierarchical structure of reasoning using model information in higher level, and the other is a parallel image processing structure used to extract plural candidate regions for a destination entity. The new points of system TOPS-3D are as follows. (1) The TOPS-3D is a three-dimensional image analysis system including 3D model construction and 3D image processing techniques. (2) A technique is proposed to increase connectivity between knowledge processing in higher level and image processing in lower level. The technique is realized by applying opening operation of mathematical morphology, in which a structural model function defined in higher level by knowledge representation is immediately used to the filter function of opening operation as image processing in lower level. The system TOPS-3D applied to 3D MRI head images consists of three levels. First and second levels are reasoning part, and third level is image processing part. In experiments, we applied 5 samples of 3D MRI head images with size 128 x 128 x 128 pixels to the system TOPS-3D to extract the regions of soft tissues such as cerebrum, cerebellum and brain stem. From the experimental results, the system is robust for variation of input data by using model information, and the position and shape of soft tissues are extracted corresponding to anatomical structure. (author)

  12. BOREAS Level-3a Landsat TM Imagery: Scaled At-sensor Radiance in BSQ Format

    Science.gov (United States)

    Nickerson, Jaime; Hall, Forrest G. (Editor); Knapp, David; Newcomer, Jeffrey A.; Cihlar, Josef

    2000-01-01

    For BOREAS, the level-3a Landsat TM data, along with the other remotely sensed images, were collected in order to provide spatially extensive information over the primary study areas. This information includes radiant energy, detailed land cover, and biophysical parameter maps such as FPAR and LAI. Although very similar in content to the level-3s Landsat TM products, the level-3a images were created to provide users with a more usable BSQ format and to provide information that permitted direct determination of per-pixel latitude and longitude coordinates. Geographically, the level-3a images cover the BOREAS NSA and SSA. Temporally, the images cover the period of 22-Jun-1984 to 30-Jul-1996. The images are available in binary, image-format files. With permission from CCRS and RSI, several of the full-resolution images are included on the BOREAS CD-ROM series. Due to copyright issues, the images not included on the CD-ROM may not be publicly available. See Sections 15 and 16 for information about how to acquire the data. Information about the images not on the CD-ROMs is provided in an inventory listing on the CD-ROMs.

  13. Design and development of a computer based simulator to support learning of radiographic image quality

    Energy Technology Data Exchange (ETDEWEB)

    Costaridou, L; Pitoura, T; Panayiotakis, G; Pallikarakis, N [Department of Medical Physics, School of Medicine, University of Patras, 265 00 Patras (Greece); Hatzis, K [Institute of Biomedical Technology, Ellinos Stratiotou 50A, 264 41 Patras (Greece)

    1994-12-31

    A training simulator has been developed to offer a structured and functional approach to radiographic imaging procedures and comprehensive understanding of interrelations between physical and technical input parameters of a radiographic imaging system and characteristics of image quality. The system addresses training needs of radiographers and radiology clinicians. The simulator is based on procedural simulation enhanced by a hypertextual model of information organization. It is supported by an image data base, which supplies and enriches the simulator. The simulation is controlled by a browsing facility which corresponds to several hierachical levels of use of the underlying multimodal data base, organized as imaging tasks. Representative tasks are : production of a single radiograph or production of functional sets of radiographs exhibiting parameter effects on image characteristics. System parameters such as patient positioning, focus to patient distance, magnification, field dimensions, focal spot size, tube voltage, tube current and exposure time are under user control. (authors). 7 refs, 2 figs.

  14. Design and development of a computer based simulator to support learning of radiographic image quality

    International Nuclear Information System (INIS)

    Costaridou, L.; Pitoura, T.; Panayiotakis, G.; Pallikarakis, N.; Hatzis, K.

    1994-01-01

    A training simulator has been developed to offer a structured and functional approach to radiographic imaging procedures and comprehensive understanding of interrelations between physical and technical input parameters of a radiographic imaging system and characteristics of image quality. The system addresses training needs of radiographers and radiology clinicians. The simulator is based on procedural simulation enhanced by a hypertextual model of information organization. It is supported by an image data base, which supplies and enriches the simulator. The simulation is controlled by a browsing facility which corresponds to several hierachical levels of use of the underlying multimodal data base, organized as imaging tasks. Representative tasks are : production of a single radiograph or production of functional sets of radiographs exhibiting parameter effects on image characteristics. System parameters such as patient positioning, focus to patient distance, magnification, field dimensions, focal spot size, tube voltage, tube current and exposure time are under user control. (authors)

  15. A Novel 2D Image Compression Algorithm Based on Two Levels DWT and DCT Transforms with Enhanced Minimize-Matrix-Size Algorithm for High Resolution Structured Light 3D Surface Reconstruction

    Science.gov (United States)

    Siddeq, M. M.; Rodrigues, M. A.

    2015-09-01

    Image compression techniques are widely used on 2D image 2D video 3D images and 3D video. There are many types of compression techniques and among the most popular are JPEG and JPEG2000. In this research, we introduce a new compression method based on applying a two level discrete cosine transform (DCT) and a two level discrete wavelet transform (DWT) in connection with novel compression steps for high-resolution images. The proposed image compression algorithm consists of four steps. (1) Transform an image by a two level DWT followed by a DCT to produce two matrices: DC- and AC-Matrix, or low and high frequency matrix, respectively, (2) apply a second level DCT on the DC-Matrix to generate two arrays, namely nonzero-array and zero-array, (3) apply the Minimize-Matrix-Size algorithm to the AC-Matrix and to the other high-frequencies generated by the second level DWT, (4) apply arithmetic coding to the output of previous steps. A novel decompression algorithm, Fast-Match-Search algorithm (FMS), is used to reconstruct all high-frequency matrices. The FMS-algorithm computes all compressed data probabilities by using a table of data, and then using a binary search algorithm for finding decompressed data inside the table. Thereafter, all decoded DC-values with the decoded AC-coefficients are combined in one matrix followed by inverse two levels DCT with two levels DWT. The technique is tested by compression and reconstruction of 3D surface patches. Additionally, this technique is compared with JPEG and JPEG2000 algorithm through 2D and 3D root-mean-square-error following reconstruction. The results demonstrate that the proposed compression method has better visual properties than JPEG and JPEG2000 and is able to more accurately reconstruct surface patches in 3D.

  16. MR imaging of the brachial plexus: comparison between 1.5-T and 3-T MR imaging: preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Tagliafico, Alberto; Neumaier, Carlo Emanuele; Calabrese, Massimo [National Institute for Cancer Research, Department of Radiology, Genova (Italy); Succio, Giulia; Serafini, Giovanni; Ghidara, Matteo [Santa Corona Hospital, Radiology Department, Savona (Italy); Martinoli, Carlo [Universita di Genova, Radiology Department, Genova (Italy)

    2011-06-15

    To compare 1.5-T and 3-T magnetic resonance (MR) imaging of the brachial plexus. Institutional review board approval and informed consent were obtained from 30 healthy volunteers and 30 consecutive patients with brachial plexus disturbances. MR was prospectively performed with comparable sequence parameters and coils with a 1.5-T and a 3-T system. Imaging protocols at both field strengths included T1-weighted turbo spin-echo (tSE) sequences and T2-weighed turbo spin-echo (tSE) sequences with fat saturation. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) between muscle and nerve were calculated for both field strengths. The visibility of brachial plexus nerve at various anatomic levels (roots, interscalene area, costoclavicular space, and axillary level) was analyzed with a four-point grading scale by two radiologists. MR imaging diagnoses and pathological findings were also compared qualitatively. SNR and CNRs were significantly higher on 3-T MR images than on 1.5-T MR images (Friedman test) for all sequences. Nerve visibility was significantly better on 3-T MR images than on 1.5-T MR images (paired sign test). Pathological findings (n = 30/30) were seen equally well with both field strengths. MR imaging diagnoses did not differ for the 1.5- and 3-T protocols. High-quality MR images of the brachial plexus can be obtained with 3-T MR imaging by using sequences similar to those used at 1.5-T MR imaging. In patients and healthy volunteers, the visibility of nerve trunks and cords at 3-T MR imaging appears to be superior to that at 1.5-T MR imaging. (orig.)

  17. Effect of feeding some evergreen tropical browse plant leaves on ...

    African Journals Online (AJOL)

    A feeding trial was conducted with thirty (30) weaner rabbits to investigate the nutritive potentials of some evergreen tropical browse plant leaves (Ficcus thoningii, Vitex doniana, Daniela oliveri, Sarcocephalus latifolia). Mixed breed rabbits were used and randomly assigned to five (5) treatments (T1 - T5). The rabbits in ...

  18. SuperPixel based mid-level image description for image recognition

    NARCIS (Netherlands)

    Tasli, H.E.; Sicre, R.; Gevers, T.

    2015-01-01

    This study proposes a mid-level feature descriptor and aims to validate improvement on image classification and retrieval tasks. In this paper, we propose a method to explore the conventional feature extraction techniques in the image classification pipeline from a different perspective where

  19. Semantics by levels: An example for an image language

    International Nuclear Information System (INIS)

    Fasciano, M.; Levialdi, S.; Tortora, G.

    1984-01-01

    Ambiguities in formal language constructs may decrease both the understanding and the coding efficiency of a program. Within an image language, two semantic levels have been detected, corresponding to the lower level (pixel-based) and to the higher level (image-based). Denotational semantics has been used to define both levels within PIXAL (an image language) in order to enable the reader to visualize a concrete application of the semantic levels and their implications in a programming environment. This paper presents the semantics of different levels of conceptualization in the abstract formal description of an image language. The disambiguation of the meaning of special purpose constructs that imply either the elementary (pixels) level or the high image (array) level is naturally obtained by means of such semantic clauses. Perhaps non Von architectures on which hierarchical computations may be performed could also benefit from the use of semantic clauses to explicit the different levels where such computations are executed

  20. The Philosophy behind a (Danish) Voice-controlled Interface to Internet Browsing for motor-handicapped

    DEFF Research Database (Denmark)

    Brøndsted, Tom

    2005-01-01

    The public-funded project "Indtal" ("Speak-it") has succeeded in developing a Danish voice-controlled utility for internet browsing targeting motor-handicapped users having difficulties using a standard keyboard and/or a standard mouse. The system underlies a number of a priori defined design cri...... with the unimodal oral mode, etc. These criteria have lead to a primarily message-driven system interacting with an existing browser on the end users' systems.......The public-funded project "Indtal" ("Speak-it") has succeeded in developing a Danish voice-controlled utility for internet browsing targeting motor-handicapped users having difficulties using a standard keyboard and/or a standard mouse. The system underlies a number of a priori defined design...

  1. A Study of Color Transformation on Website Images for the Color Blind

    OpenAIRE

    Siew-Li Ching; Maziani Sabudin

    2010-01-01

    In this paper, we study on color transformation method on website images for the color blind. The most common category of color blindness is red-green color blindness which is viewed as beige color. By transforming the colors of the images, the color blind can improve their color visibility. They can have a better view when browsing through the websites. To transform colors on the website images, we study on two algorithms which are the conversion techniques from RGB colo...

  2. Effects of fire and browsing on regeneration of blue oak

    Science.gov (United States)

    James W. Bartolome; Mitchel P. McClaran; Barbara H. Allen-Diaz; Jim Dunne; Lawrence D. Ford; Richard B. Standiford; Neil K. McDougald; Larry C. Forero

    2002-01-01

    Blue oaks (Quercus douglasii) are not regenerating well over much of California. The roles of fire and browsing in regeneration are probably significant, but poorly understood. We burned two foothill blue oak woodland sites which contained significant numbers of small trees between 40 and 70 cm tall, then compared height growth over 14 years among 48...

  3. SENTINEL-2 LEVEL 1 PRODUCTS AND IMAGE PROCESSING PERFORMANCES

    Directory of Open Access Journals (Sweden)

    S. J. Baillarin

    2012-07-01

    . The stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m and multi-temporal (better than 0.3 pixels cases. Then, the prototyped image processing techniques (both radiometric and geometric will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …. Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

  4. SENTINEL-2 Level 1 Products and Image Processing Performances

    Science.gov (United States)

    Baillarin, S. J.; Meygret, A.; Dechoz, C.; Petrucci, B.; Lacherade, S.; Tremas, T.; Isola, C.; Martimort, P.; Spoto, F.

    2012-07-01

    stringent image quality requirements are also described, in particular the geo-location accuracy for both absolute (better than 12.5 m) and multi-temporal (better than 0.3 pixels) cases. Then, the prototyped image processing techniques (both radiometric and geometric) will be addressed. The radiometric corrections will be first introduced. They consist mainly in dark signal and detector relative sensitivity correction, crosstalk correction and MTF restoration. Then, a special focus will be done on the geometric corrections. In particular the innovative method of automatic enhancement of the geometric physical model will be detailed. This method takes advantage of a Global Reference Image database, perfectly geo-referenced, to correct the physical geometric model of each image taken. The processing is based on an automatic image matching process which provides accurate ground control points between a given band of the image to refine and a reference image, allowing to dynamically calibrate the viewing model. The generation of the Global Reference Image database made of Sentinel-2 pre-calibrated mono-spectral images will be also addressed. In order to perform independent validation of the prototyping activity, an image simulator dedicated to Sentinel-2 has been set up. Thanks to this, a set of images have been simulated from various source images and combining different acquisition conditions and landscapes (mountains, deserts, cities …). Given disturbances have been also simulated so as to estimate the end to end performance of the processing chain. Finally, the radiometric and geometric performances obtained by the prototype will be presented. In particular, the geo-location performance of the level-1C products which widely fulfils the image quality requirements will be provided.

  5. Effects of intra-operative fluoroscopic 3D-imaging on peri-operative imaging strategy in calcaneal fracture surgery.

    Science.gov (United States)

    Beerekamp, M S H; Backes, M; Schep, N W L; Ubbink, D T; Luitse, J S; Schepers, T; Goslings, J C

    2017-12-01

    Previous studies demonstrated that intra-operative fluoroscopic 3D-imaging (3D-imaging) in calcaneal fracture surgery is promising to prevent revision surgery and save costs. However, these studies limited their focus to corrections performed after 3D-imaging, thereby neglecting corrections after intra-operative fluoroscopic 2D-imaging (2D-imaging). The aim of this study was to assess the effects of additional 3D-imaging on intra-operative corrections, peri-operative imaging used, and patient-relevant outcomes compared to 2D-imaging alone. In this before-after study, data of adult patients who underwent open reduction and internal fixation (ORIF) of a calcaneal fracture between 2000 and 2014 in our level-I Trauma center were collected. 3D-imaging (BV Pulsera with 3D-RX, Philips Healthcare, Best, The Netherlands) was available as of 2007 at the surgeons' discretion. Patient and fracture characteristics, peri-operative imaging, intra-operative corrections and patient-relevant outcomes were collected from the hospital databases. Patients in whom additional 3D-imaging was applied were compared to those undergoing 2D-imaging alone. A total of 231 patients were included of whom 107 (46%) were operated with the use of 3D-imaging. No significant differences were found in baseline characteristics. The median duration of surgery was significantly longer when using 3D-imaging (2:08 vs. 1:54 h; p = 0.002). Corrections after additional 3D-imaging were performed in 53% of the patients. However, significantly fewer corrections were made after 2D-imaging when 3D-imaging was available (Risk difference (RD) -15%; 95% Confidence interval (CI) -29 to -2). Peri-operative imaging, besides intra-operative 3D-imaging, and patient-relevant outcomes were similar between groups. Intra-operative 3D-imaging provides additional information resulting in additional corrections. Moreover, 3D-imaging probably changed the surgeons' attitude to rely more on 3D-imaging, hence a 15%-decrease of

  6. The transfer of fallout cesium-137 from browse to moose. Part 1

    International Nuclear Information System (INIS)

    Zach, R.; Mayoh, K.R.

    1982-09-01

    We are investigating the transfer of fallout cesium-137 from soil to browse to moose (Alces alces) to wolf (Canis lupis) to promote our understanding of the movement of radionuclides through natural food chains. The first part of this study is concerned with moose food habits. Early winter food habits of moose from Hecla Island and Manitoba Game Hunting Area 26 in south central and south eastern Manitoba were studied. In 86 rumen samples, 25 food types were identified. Three methods of food habit determination were used: (1) percentage occurrence of food types, (2) subjective abundance scores and (3) percentage dry weight. All three methods yielded very similar results

  7. A novel strategy to access high resolution DICOM medical images based on JPEG2000 interactive protocol

    Science.gov (United States)

    Tian, Yuan; Cai, Weihua; Sun, Jianyong; Zhang, Jianguo

    2008-03-01

    The demand for sharing medical information has kept rising. However, the transmission and displaying of high resolution medical images are limited if the network has a low transmission speed or the terminal devices have limited resources. In this paper, we present an approach based on JPEG2000 Interactive Protocol (JPIP) to browse high resolution medical images in an efficient way. We designed and implemented an interactive image communication system with client/server architecture and integrated it with Picture Archiving and Communication System (PACS). In our interactive image communication system, the JPIP server works as the middleware between clients and PACS servers. Both desktop clients and wireless mobile clients can browse high resolution images stored in PACS servers via accessing the JPIP server. The client can only make simple requests which identify the resolution, quality and region of interest and download selected portions of the JPEG2000 code-stream instead of downloading and decoding the entire code-stream. After receiving a request from a client, the JPIP server downloads the requested image from the PACS server and then responds the client by sending the appropriate code-stream. We also tested the performance of the JPIP server. The JPIP server runs stably and reliably under heavy load.

  8. A Novel Approach to Discovery and Image Access in the Petabyte Age

    Science.gov (United States)

    Mueller, D.; Dimitoglou, G.; Alexanderian, A.; Garcia Ortiz, J.; Schmidt, L.; Hughitt, V. K.; Ireland, J.; Fleck, B.

    2009-12-01

    Space missions generate an ever-growing amount of data, as impressively highlighted by the Solar Dynamics Observatory's expected data rate of 1.4 Terabyte per day. In order to fully exploit their data, scientists need to be able to browse and visualize many different data products spanning a large range of physical length and time scales. So far, the tools available to the scientific community either require downloading all potentially relevant data sets beforehand in their entirety or provide only movies with a fixed resolution and cadence. To facilitate browsing and analysis of complex time-dependent data sets from multiple sources, we are developing JHelioviewer, a JPEG 2000-based visualization and discovery infrastructure for image data. Currently focused on solar physics data, it can easily be adapted for use in other areas of space and earth sciences. Together with its web-based counterpart helioviewer.org, JHelioviewer offers intuitive ways to browse large amounts of heterogeneous data remotely and allows users to search related event data bases. The user interface for JHelioviewer is a multi-platform Java client that can both communicate with a remote server via the JPEG 2000 interactive protocol JPIP and open local data. The random code stream access of JPIP minimizes data transfer and can encapsulate meta data as well as multiple image channels in one data stream. This presentation will illustrate some of the features of JHelioviewer and the advantages of JPEG 2000 as a new data compression standard.

  9. Opportunities in Participatory Science and Citizen Science with MRO's High Resolution Imaging Science Experiment: A Virtual Science Team Experience

    Science.gov (United States)

    Gulick, Ginny

    2009-09-01

    We report on the accomplishments of the HiRISE EPO program over the last two and a half years of science operations. We have focused primarily on delivering high impact science opportunities through our various participatory science and citizen science websites. Uniquely, we have invited students from around the world to become virtual HiRISE team members by submitting target suggestions via our HiRISE Quest Image challenges using HiWeb the team's image suggestion facility web tools. When images are acquired, students analyze their returned images, write a report and work with a HiRISE team member to write a image caption for release on the HiRISE website (http://hirise.lpl.arizona.edu). Another E/PO highlight has been our citizen scientist effort, HiRISE Clickworkers (http://clickworkers.arc.nasa.gov/hirise). Clickworkers enlists volunteers to identify geologic features (e.g., dunes, craters, wind streaks, gullies, etc.) in the HiRISE images and help generate searchable image databases. In addition, the large image sizes and incredible spatial resolution of the HiRISE camera can tax the capabilities of the most capable computers, so we have also focused on enabling typical users to browse, pan and zoom the HiRISE images using our HiRISE online image viewer (http://marsoweb.nas.nasa.gov/HiRISE/hirise_images/). Our educational materials available on the HiRISE EPO web site (http://hirise.seti.org/epo) include an assortment of K through college level, standards-based activity books, a K through 3 coloring/story book, a middle school level comic book, and several interactive educational games, including Mars jigsaw puzzles, crosswords, word searches and flash cards.

  10. Quantitative 3-dimensional imaging of auxin and cytokinin levels in transgenic soybean and medicago truncatula roots via two-photon induced fluorescence imaging

    Science.gov (United States)

    Fisher, Jon; Gaillard, Paul; Nurmalasari, Ni Putu Dewi; Fellbaum, Carl; Subramaniam, Sen; Smith, Steve

    2018-02-01

    Industrial nitrogen fertilizers account for nearly 50% of the fossil fuel costs in modern agriculture and contribute to soil and water pollution. Therefore, significant interest exists in understanding and characterizing the efficiency of nitrogen fixation, and the biochemical signaling pathways which orchestrate the plant-microbial symbiosis through which plants fix nitrogen. Legume plant species exhibit a particularly efficient nitrogen uptake mechanism, using root nodules which house nitrogen-fixing rhizobial bacteria. While nodule development has been widely studied, there remain significant gaps in understanding the regulatory hormones' role in plant development. In this work, we produce 3-dimensional maps of auxin (AX) and cytokinin (CK) hormone concentrations within model plant root tips and nodules with respect to root architecture and cell type. Soybean and Medicago plants were transfected with a two-color fluorescent vector with AXsensitive green fluorescent protein (GFP) and CK-sensitive TdTomato (TdT). 3D images of soybean root nodules were captured using two-photon induced fluorescence microscopy. The resulting images were computationally analyzed using the localization code first developed by Weeks and later adapted by Kilfoil, and analyzed in the context of the root architecture. Statistical analysis of the resulting 3D hormone level maps reproduce-well the known roles of AX and CK in developing plant roots, and are the first quantitative description of these regulatory hormones tied to specific plant architecture. The analytical methods used, and the spatial distribution of these key regulatory hormones in plant roots, nodule primordia and root nodules, and their statistical interpretation are presented.

  11. The Use of QBIC Content-Based Image Retrieval System

    Directory of Open Access Journals (Sweden)

    Ching-Yi Wu

    2004-03-01

    Full Text Available The fast increase in digital images has caught increasing attention on the development of image retrieval technologies. Content-based image retrieval (CBIR has become an important approach in retrieving image data from a large collection. This article reports our results on the use and users study of a CBIR system. Thirty-eight students majored in art and design were invited to use the IBM’s OBIC (Query by Image Content system through the Internet. Data from their information needs, behaviors, and retrieval strategies were collected through an in-depth interview, observation, and self-described think-aloud process. Important conclusions are:(1)There are four types of information needs for image data: implicit, inspirational, ever-changing, and purposive. The types of needs may change during the retrieval process. (2)CBIR is suitable for the example-type query, text retrieval is suitable for the scenario-type query, and image browsing is suitable for the symbolic query. (3)Different from text retrieval, detailed description of the query condition may lead to retrieval failure more easily. (4)CBIR is suitable for the domain-specific image collection, not for the images on the Word-Wide Web.[Article content in Chinese

  12. TouchWB : Touch behavioral user authentication based on web browsing on smartphones

    DEFF Research Database (Denmark)

    Meng, Weizhi; Wang, Yu; Wong, Duncan S.

    2018-01-01

    browsing gestures. For evaluation, we implemented the scheme on Android phones and conducted a user study involving 48 participants. Experimental results demonstrated that our approach could reduce the touch behavioral deviation by nearly half and achieve an average error rate of about 2.4% by using...

  13. Foliar essential oils and deer browsing preference of Douglas-fir genotypes

    Science.gov (United States)

    M.A. Radwan

    1978-01-01

    Yield and composition of essential oils were compared in foliage of Douglas-fir. Five clones with different susceptibilities to deer browsing were used; foliage was collected during the dormant season. There were no qualitative differences among the oils of the different clones, but the oils differed quantitatively in all variables measured. Eight variables appeared...

  14. A Tool and Application Programming Interface for Browsing Historical Geostationary Satellite Data

    Science.gov (United States)

    Chee, T.; Nguyen, L.; Minnis, P.; Spangenberg, D.; Ayers, J.

    2013-12-01

    Providing access to information is a key concern for NASA Langley Research Center. We describe a tool and method that allows end users to easily browse and access information that is otherwise difficult to acquire and manipulate. The tool described has as its core the application-programming interface that is made available to the public. One goal of the tool is to provide a demonstration to end users so that they can use the enhanced imagery as an input into their own work flows. This project builds upon NASA Langley Cloud and Radiation Group's experience with making real-time and historical satellite imagery accessible and easily searchable. As we see the increasing use of virtual supply chains that provide additional value at each link there is value in making satellite imagery available through a simple access method as well as allowing users to browse and view that imagery as they need rather than in a manner most convenient for the data provider.

  15. Reconstruction of incomplete cell paths through a 3D-2D level set segmentation

    Science.gov (United States)

    Hariri, Maia; Wan, Justin W. L.

    2012-02-01

    Segmentation of fluorescent cell images has been a popular technique for tracking live cells. One challenge of segmenting cells from fluorescence microscopy is that cells in fluorescent images frequently disappear. When the images are stacked together to form a 3D image volume, the disappearance of the cells leads to broken cell paths. In this paper, we present a segmentation method that can reconstruct incomplete cell paths. The key idea of this model is to perform 2D segmentation in a 3D framework. The 2D segmentation captures the cells that appear in the image slices while the 3D segmentation connects the broken cell paths. The formulation is similar to the Chan-Vese level set segmentation which detects edges by comparing the intensity value at each voxel with the mean intensity values inside and outside of the level set surface. Our model, however, performs the comparison on each 2D slice with the means calculated by the 2D projected contour. The resulting effect is to segment the cells on each image slice. Unlike segmentation on each image frame individually, these 2D contours together form the 3D level set function. By enforcing minimum mean curvature on the level set surface, our segmentation model is able to extend the cell contours right before (and after) the cell disappears (and reappears) into the gaps, eventually connecting the broken paths. We will present segmentation results of C2C12 cells in fluorescent images to illustrate the effectiveness of our model qualitatively and quantitatively by different numerical examples.

  16. Advanced 3-D Ultrasound Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Morten Fischer

    The main purpose of the PhD project was to develop methods that increase the 3-D ultrasound imaging quality available for the medical personnel in the clinic. Acquiring a 3-D volume gives the medical doctor the freedom to investigate the measured anatomy in any slice desirable after the scan has...... been completed. This allows for precise measurements of organs dimensions and makes the scan more operator independent. Real-time 3-D ultrasound imaging is still not as widespread in use in the clinics as 2-D imaging. A limiting factor has traditionally been the low image quality achievable using...... a channel limited 2-D transducer array and the conventional 3-D beamforming technique, Parallel Beamforming. The first part of the scientific contributions demonstrate that 3-D synthetic aperture imaging achieves a better image quality than the Parallel Beamforming technique. Data were obtained using both...

  17. Multi-domain, higher order level set scheme for 3D image segmentation on the GPU

    DEFF Research Database (Denmark)

    Sharma, Ojaswa; Zhang, Qin; Anton, François

    2010-01-01

    to evaluate level set surfaces that are $C^2$ continuous, but are slow due to high computational burden. In this paper, we provide a higher order GPU based solver for fast and efficient segmentation of large volumetric images. We also extend the higher order method to multi-domain segmentation. Our streaming...

  18. Assessing human health risks from pesticide use in conventional and innovative cropping systems with the BROWSE model.

    Science.gov (United States)

    Lammoglia, Sabine-Karen; Kennedy, Marc C; Barriuso, Enrique; Alletto, Lionel; Justes, Eric; Munier-Jolain, Nicolas; Mamy, Laure

    2017-08-01

    Reducing the risks and impacts of pesticide use on human health and on the environment is one of the objectives of the European Commission Directive 2009/128/EC in the quest for a sustainable use of pesticides. This Directive, developed through European national plans such as Ecophyto plan in France, promotes the introduction of innovative cropping systems relying, for example, on integrated pest management. Risk assessment for human health of the overall pesticide use in these innovative systems is required before the introduction of those systems to avoid that an innovation becomes a new problem. The objectives of this work were to assess and to compare (1) the human exposure to pesticides used in conventional and innovative cropping systems designed to reduce pesticide needs, and (2) the corresponding risks for human health. Humans (operator and residents) exposure to pesticides and risks for human health were assessed for each pesticide with the BROWSE model. Then, a method was proposed to represent the overall risk due to all pesticides used in one system. This study considers 3 conventional and 9 associated innovative cropping systems, and 116 plant protection products containing 89 different active substances (i.e. pesticides). The modelling results obtained with BROWSE showed that innovative cropping systems such as low input or no herbicide systems would reduce the risk for human health in comparison to the corresponding conventional cropping systems. On the contrary, BROWSE showed that conservation tillage system would lead to unacceptable risks in the conditions of our study, because of a high number of pesticide applications, and especially of some herbicides. For residents, the dermal absorption was the main exposure route while ingestion was found to be negligible. For operators, inhalation was also a predominant route of exposure. In general, human exposure to pesticides and human health risks were found to be correlated to the treatment frequency

  19. The Auroral Planetary Imaging and Spectroscopy (APIS) service

    Science.gov (United States)

    Lamy, L.; Prangé, R.; Henry, F.; Le Sidaner, P.

    2015-06-01

    The Auroral Planetary Imaging and Spectroscopy (APIS) service, accessible online, provides an open and interactive access to processed auroral observations of the outer planets and their satellites. Such observations are of interest for a wide community at the interface between planetology, magnetospheric and heliospheric physics. APIS consists of (i) a high level database, built from planetary auroral observations acquired by the Hubble Space Telescope (HST) since 1997 with its mostly used Far-Ultraviolet spectro-imagers, (ii) a dedicated search interface aimed at browsing efficiently this database through relevant conditional search criteria and (iii) the ability to interactively work with the data online through plotting tools developed by the Virtual Observatory (VO) community, such as Aladin and Specview. This service is VO compliant and can therefore also been queried by external search tools of the VO community. The diversity of available data and the capability to sort them out by relevant physical criteria shall in particular facilitate statistical studies, on long-term scales and/or multi-instrumental multi-spectral combined analysis.

  20. Browse diversity and iron loading in captive sumatran rhinoceroses (Dicerorhinus sumatrensis): a comparison of sanctuary and zoological populations.

    Science.gov (United States)

    Candra, Dedi; Radcliffe, Robin W; Andriansyah; Khan, Mohammad; Tsu, I-Hsien; Paglia, Donald E

    2012-09-01

    Iron storage disease (ISD) is now recognized as a serious clinical disorder acquired by two species of browsing rhinoceroses, the African black (Diceros bicornis) and the Asian Sumatran (Dicerorhinus sumatrensis) rhinoceroses, when displaced from their natural habitats. The most complete knowledge of ISD comes from studies of the black rhinoceros, but the Asian species is also at risk. Sumatran rhinoceroses housed in traditional zoological settings outside of range countries have suffered significant morbidity and mortality potentially related to ISD induced by diet and/or other confinement conditions. With so few animals in captivity, very little information exists on iron loading in the Sumatran rhinoceros. To better characterize the problem, we retrospectively compared captive management conditions of Sumatran rhinoceroses housed under traditional zoological care with those in two native sanctuary environments. In general, zoo rhinoceroses are offered a paucity of plants and browse species compared with their sanctuary and wild counterparts managed in native rainforest habitats. Iron analyte levels and limited histopathologic observations in these populations suggest variable tendencies to overload iron, dependent upon differences in managed diet and individual food preferences. More detailed investigation of these markedly dissimilar ex situ populations is warranted to better understand the role of nutrition and other conditions affecting iron loading in browser rhinoceroses.

  1. Multimodal imaging of the human knee down to the cellular level

    Science.gov (United States)

    Schulz, G.; Götz, C.; Müller-Gerbl, M.; Zanette, I.; Zdora, M.-C.; Khimchenko, A.; Deyhle, H.; Thalmann, P.; Müller, B.

    2017-06-01

    Computed tomography reaches the best spatial resolution for the three-dimensional visualization of human tissues among the available nondestructive clinical imaging techniques. Nowadays, sub-millimeter voxel sizes are regularly obtained. Regarding investigations on true micrometer level, lab-based micro-CT (μCT) has become gold standard. The aim of the present study is firstly the hierarchical investigation of a human knee post mortem using hard X-ray μCT and secondly a multimodal imaging using absorption and phase contrast modes in order to investigate hard (bone) and soft (cartilage) tissues on the cellular level. After the visualization of the entire knee using a clinical CT, a hierarchical imaging study was performed using the lab-system nanotom® m. First, the entire knee was measured with a pixel length of 65 μm. The highest resolution with a pixel length of 3 μm could be achieved after extracting cylindrically shaped plugs from the femoral bones. For the visualization of the cartilage, grating-based phase contrast μCT (I13-2, Diamond Light Source) was performed. With an effective voxel size of 2.3 μm it was possible to visualize individual chondrocytes within the cartilage.

  2. 3D Virtual CH Interactive Information Systems for a smart web browsing experience for desktop PCs and mobile devices

    Directory of Open Access Journals (Sweden)

    A. Scianna

    2018-05-01

    Full Text Available Recently, the diffusion of knowledge on Cultural Heritage (CH has become an element of primary importance for its valorization. At the same time, the diffusion of surveys based on UAV Unmanned Aerial Vehicles (UAV technologies and new methods of photogrammetric reconstruction have opened new possibilities for 3D CH representation. Furthermore the recent development of faster and more stable internet connections leads people to increase the use of mobile devices. In the light of all this, the importance of the development of Virtual Reality (VR environments applied to CH is strategic for the diffusion of knowledge in a smart solution. In particular, the present work shows how, starting from a basic survey and the further photogrammetric reconstruction of a cultural good, is possible to built a 3D CH interactive information system useful for desktop and mobile devices. For this experimentation the Arab-Norman church of the Trinity of Delia (in Castelvetrano-Sicily-Italy has been adopted as case study. The survey operations have been carried out considering different rapid methods of acquisition (UAV camera, SLR camera and smartphone camera. The web platform to publish the 3D information has been built using HTML5 markup language and WebGL JavaScript libraries (Three.js libraries. This work presents the construction of a 3D navigation system for a web-browsing of a virtual CH environment, with the integration of first person controls and 3D popup links. This contribution adds a further step to enrich the possibilities of open-source technologies applied to the world of CH valorization on web.

  3. Complex adaptation-based LDR image rendering for 3D image reconstruction

    Science.gov (United States)

    Lee, Sung-Hak; Kwon, Hyuk-Ju; Sohng, Kyu-Ik

    2014-07-01

    A low-dynamic tone-compression technique is developed for realistic image rendering that can make three-dimensional (3D) images similar to realistic scenes by overcoming brightness dimming in the 3D display mode. The 3D surround provides varying conditions for image quality, illuminant adaptation, contrast, gamma, color, sharpness, and so on. In general, gain/offset adjustment, gamma compensation, and histogram equalization have performed well in contrast compression; however, as a result of signal saturation and clipping effects, image details are removed and information is lost on bright and dark areas. Thus, an enhanced image mapping technique is proposed based on space-varying image compression. The performance of contrast compression is enhanced with complex adaptation in a 3D viewing surround combining global and local adaptation. Evaluating local image rendering in view of tone and color expression, noise reduction, and edge compensation confirms that the proposed 3D image-mapping model can compensate for the loss of image quality in the 3D mode.

  4. Timber, Browse, and Herbage on Selected Loblolly-Shortleaf Pine-Hardwood Forest Stands

    Science.gov (United States)

    Gale L. Wolters; Alton Martin; Warren P. Clary

    1977-01-01

    A thorough vegetation inventory was made on loblolly-shortleaf pine-hardwood stands scheduled by forest industry for clearcutting, site preparation, and planting to pine in north central Louisiana and southern Arkansas. Overstory timber, on the average, contained about equal proportions of softwood and hardwood basal area. Browse plants ranged from 5,500 to over 70,...

  5. 3-D Imaging Using Row-Column-Addressed Arrays With Integrated Apodization

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Rasmussen, Morten Fischer; Bagge, Jan Peter

    2015-01-01

    Pa, and the sensitivity was 0.299 ± 0.090 V/Pa. The nearest neighbor crosstalk level was -23.9 ± 3.7 dB, while the transmit-to-receive-elements crosstalk level was -40.2 ± 3.5 dB. Imaging of a 0.3-mm-diameter steel wire using synthetic transmit focusing with 62 single-element emissions demonstrated axial and lateral...

  6. Level set segmentation of bovine corpora lutea in ex situ ovarian ultrasound images

    Directory of Open Access Journals (Sweden)

    Adams Gregg P

    2008-08-01

    Full Text Available Abstract Background The objective of this study was to investigate the viability of level set image segmentation methods for the detection of corpora lutea (corpus luteum, CL boundaries in ultrasonographic ovarian images. It was hypothesized that bovine CL boundaries could be located within 1–2 mm by a level set image segmentation methodology. Methods Level set methods embed a 2D contour in a 3D surface and evolve that surface over time according to an image-dependent speed function. A speed function suitable for segmentation of CL's in ovarian ultrasound images was developed. An initial contour was manually placed and contour evolution was allowed to proceed until the rate of change of the area was sufficiently small. The method was tested on ovarian ultrasonographic images (n = 8 obtained ex situ. A expert in ovarian ultrasound interpretation delineated CL boundaries manually to serve as a "ground truth". Accuracy of the level set segmentation algorithm was determined by comparing semi-automatically determined contours with ground truth contours using the mean absolute difference (MAD, root mean squared difference (RMSD, Hausdorff distance (HD, sensitivity, and specificity metrics. Results and discussion The mean MAD was 0.87 mm (sigma = 0.36 mm, RMSD was 1.1 mm (sigma = 0.47 mm, and HD was 3.4 mm (sigma = 2.0 mm indicating that, on average, boundaries were accurate within 1–2 mm, however, deviations in excess of 3 mm from the ground truth were observed indicating under- or over-expansion of the contour. Mean sensitivity and specificity were 0.814 (sigma = 0.171 and 0.990 (sigma = 0.00786, respectively, indicating that CLs were consistently undersegmented but rarely did the contour interior include pixels that were judged by the human expert not to be part of the CL. It was observed that in localities where gradient magnitudes within the CL were strong due to high contrast speckle, contour expansion stopped too early. Conclusion The

  7. Shape-based interpolation of multidimensional grey-level images

    International Nuclear Information System (INIS)

    Grevera, G.J.; Udupa, J.K.

    1996-01-01

    Shape-based interpolation as applied to binary images causes the interpolation process to be influenced by the shape of the object. It accomplishes this by first applying a distance transform to the data. This results in the creation of a grey-level data set in which the value at each point represents the minimum distance from that point to the surface of the object. (By convention, points inside the object are assigned positive values; points outside are assigned negative values.) This distance transformed data set is then interpolated using linear or higher-order interpolation and is then thresholded at a distance value of zero to produce the interpolated binary data set. In this paper, the authors describe a new method that extends shape-based interpolation to grey-level input data sets. This generalization consists of first lifting the n-dimensional (n-D) image data to represent it as a surface, or equivalently as a binary image, in an (n + 1)-dimensional [(n + 1)-D] space. The binary shape-based method is then applied to this image to create an (n + 1)-D binary interpolated image. Finally, this image is collapsed (inverse of lifting) to create the n-D interpolated grey-level data set. The authors have conducted several evaluation studies involving patient computed tomography (CT) and magnetic resonance (MR) data as well as mathematical phantoms. They all indicate that the new method produces more accurate results than commonly used grey-level linear interpolation methods, although at the cost of increased computation

  8. Acceptable levels of digital image compression in chest radiology

    International Nuclear Information System (INIS)

    Smith, I.

    2000-01-01

    The introduction of picture archival and communications systems (PACS) and teleradiology has prompted an examination of techniques that optimize the storage capacity and speed of digital storage and distribution networks. The general acceptance of the move to replace conventional screen-film capture with computed radiography (CR) is an indication that clinicians within the radiology community are willing to accept images that have been 'compressed'. The question to be answered, therefore, is what level of compression is acceptable. The purpose of the present study is to provide an assessment of the ability of a group of imaging professionals to determine whether an image has been compressed. To undertake this study a single mobile chest image, selected for the presence of some subtle pathology in the form of a number of septal lines in both costphrenic angles, was compressed to levels of 10:1, 20:1 and 30:1. These images were randomly ordered and shown to the observers for interpretation. Analysis of the responses indicates that in general it was not possible to distinguish the original image from its compressed counterparts. Furthermore, a preference appeared to be shown for images that have undergone low levels of compression. This preference can most likely be attributed to the 'de-noising' effect of the compression algorithm at low levels. Copyright (1999) Blackwell Science Pty. Ltd

  9. Breast Imaging: The Face of Imaging 3.0.

    Science.gov (United States)

    Mayo, Ray Cody; Parikh, Jay R

    2016-08-01

    In preparation for impending changes to the health care delivery and reimbursement models, the ACR has provided a roadmap for success via the Imaging 3.0 (®)platform. The authors illustrate how the field of breast imaging demonstrates the following Imaging 3.0 concepts: value, patient-centered care, clinical integration, structured reporting, outcome metrics, and radiology's role in the accountable care organization environment. Much of breast imaging's success may be adapted and adopted by other fields in radiology to ensure that all radiologists become more visible and provide the value sought by patients and payers. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  10. Proton therapy for prostate cancer treatment employing online image guidance and an action level threshold.

    Science.gov (United States)

    Vargas, Carlos; Falchook, Aaron; Indelicato, Daniel; Yeung, Anamaria; Henderson, Randall; Olivier, Kenneth; Keole, Sameer; Williams, Christopher; Li, Zuofeng; Palta, Jatinder

    2009-04-01

    The ability to determine the accuracy of the final prostate position within a determined action level threshold for image-guided proton therapy is unclear. Three thousand one hundred ten images for 20 consecutive patients treated in 1 of our 3 proton prostate protocols from February to May of 2007 were analyzed. Daily kV images and patient repositioning were performed employing an action-level threshold (ALT) of > or = 2.5 mm for each beam. Isocentric orthogonal x-rays were obtained, and prostate position was defined via 3 gold markers for each patient in the 3 axes. To achieve and confirm our action level threshold, an average of 2 x-rays sets (median 2; range, 0-4) was taken daily for each patient. Based on our ALT, we made no corrections in 8.7% (range, 0%-54%), 1 correction in 82% (41%-98%), and 2 to 3 corrections in 9% (0-27%). No patient needed 4 or more corrections. All patients were treated with a confirmed error of < 2.5 mm for every beam delivered. After all corrections, the mean and standard deviations were: anterior-posterior (z): 0.003 +/- 0.094 cm; superior-inferior (y): 0.028 +/- 0.073 cm; and right-left (x) -0.013 +/- 0.08 cm. It is feasible to limit all final prostate positions to less than 2.5 mm employing an action level image-guided radiation therapy (IGRT) process. The residual errors after corrections were very small.

  11. Browse species from Ethiopia: role in methane reduction and nematode control in goats

    NARCIS (Netherlands)

    Mengistu, Genet F.

    2017-01-01

    The aim of the research reported in this thesis was to evaluate browse species collected from Ethiopia for preference by goats, and for their in vitro anthelmintic and methane (CH4) reduction properties. During the conduct of the studies observations were made warranting a further aim,

  12. A segmentation and classification scheme for single tooth in MicroCT images based on 3D level set and k-means+.

    Science.gov (United States)

    Wang, Liansheng; Li, Shusheng; Chen, Rongzhen; Liu, Sze-Yu; Chen, Jyh-Cheng

    2017-04-01

    Accurate classification of different anatomical structures of teeth from medical images provides crucial information for the stress analysis in dentistry. Usually, the anatomical structures of teeth are manually labeled by experienced clinical doctors, which is time consuming. However, automatic segmentation and classification is a challenging task because the anatomical structures and surroundings of the tooth in medical images are rather complex. Therefore, in this paper, we propose an effective framework which is designed to segment the tooth with a Selective Binary and Gaussian Filtering Regularized Level Set (GFRLS) method improved by fully utilizing 3 dimensional (3D) information, and classify the tooth by employing unsupervised learning i.e., k-means++ method. In order to evaluate the proposed method, the experiments are conducted on the sufficient and extensive datasets of mandibular molars. The experimental results show that our method can achieve higher accuracy and robustness compared to other three clustering methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Efficient One-click Browsing of Large Trajectory Sets

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin

    2014-01-01

    presents a novel query type called sheaf, where users can browse trajectory data sets using a single mouse click. Sheaves are very versatile and can be used for location-based advertising, travel-time analysis, intersection analysis, and reachability analysis (isochrones). A novel in-memory trajectory...... index compresses the data by a factor of 12.4 and enables execution of sheaf queries in 40 ms. This is up to 2 orders of magnitude faster than existing work. We demonstrate the simplicity, versatility, and efficiency of sheaf queries using a real-world trajectory set consisting of 2.7 million...

  14. A Skyline Plugin for Pathway-Centric Data Browsing

    Energy Technology Data Exchange (ETDEWEB)

    Degan, Michael G.; Ryadinskiy, Lillian; Fujimoto, Grant M.; Wilkins, Christopher S.; Lichti, Cheryl F.; Payne, Samuel H.

    2016-08-16

    For targeted proteomics to be broadly adopted in biological laboratories as a routine experimental protocol, wet-bench biologists must be able to approach SRM assay design in the same way they approach biological experimental design. Most often, biological hypotheses are envisioned in a set of protein interactions, networks and pathways. We present a plugin for the popular Skyline tool that presents public mass spectrometry data in a pathway-centric view to assist users in browsing available data and determining how to design quantitative experiments. Selected proteins and their underlying mass spectra are imported to Skyline for further assay design (transition selection). The same plugin can be used for hypothesis-drive DIA data analysis, again utilizing the pathway view to help narrow down the set of proteins which will be investigated. The plugin is backed by the PNNL Biodiversity Library, a corpus of 3 million peptides from >100 organisms, and the draft human proteome. Users can upload personal data to the plugin to use the pathway navigation prior to importing their own data into Skyline.

  15. Fruiting of browse plants affected by pine site preparation in east Texas

    Science.gov (United States)

    John J. Stransky; Douglas Richardson

    1977-01-01

    Pine planting sites prepared by burning yielded 120 kg/ha of browse fruits the third growing season after site treatment. Control plots yielded 74, KG-bladed plots 57, and chopped plots 41 kg/ha. Blackberries, American beautyberry, sumac, Sebastian bush, muscadine grape, blueberries, and southern wax-myrtle were the principal species. Most fruit was available in summer...

  16. Phenotypic sex ratios of Atriplex canescens shrubs in relation to cattle browsing

    Science.gov (United States)

    Andres F. Cibils; David M. Swift; Richard H. Hart

    2001-01-01

    Previous studies conducted at our research site on the shortgrass steppe in Colorado showed that phenotypic sex ratios of tetraploid fourwing saltbush (Atriplex canescens Pursh [Nutt]) shrubs were less female biased in grazed pastures than in adjacent exclosures. The potential effects of cattle browsing on shrub sex ratios were studied both in the field and in a...

  17. Retrieval Architecture with Classified Query for Content Based Image Recognition

    Directory of Open Access Journals (Sweden)

    Rik Das

    2016-01-01

    Full Text Available The consumer behavior has been observed to be largely influenced by image data with increasing familiarity of smart phones and World Wide Web. Traditional technique of browsing through product varieties in the Internet with text keywords has been gradually replaced by the easy accessible image data. The importance of image data has portrayed a steady growth in application orientation for business domain with the advent of different image capturing devices and social media. The paper has described a methodology of feature extraction by image binarization technique for enhancing identification and retrieval of information using content based image recognition. The proposed algorithm was tested on two public datasets, namely, Wang dataset and Oliva and Torralba (OT-Scene dataset with 3688 images on the whole. It has outclassed the state-of-the-art techniques in performance measure and has shown statistical significance.

  18. Calibration and validation of the 14C-labelled polyethylene glycol-binding assay for tannins in tropical browse

    International Nuclear Information System (INIS)

    Mlambo, V.; Makkar, H.P.S.

    2005-01-01

    This study evaluates the radiolabelled polyethylene glycol (PEG)-binding procedure [Silanikove, N., Shinder, D., Gilboa, N., Eyal, M., Nitsan, Z., 1996. Polyethylene glycol-binding to plant samples as an assay for the biological effects of tannins: predicting the negative effects of tannins in Mediterranean browse on rumen degradation. J. Agric. Food Chem. 44, 3230-3234] for tannin analysis, using 27 tropical browse plants. In this method, the amount of PEG bound to a plant sample is assumed to be a reflection of its tannin content. The method was modified to exclude the use of non-tanniniferous substrate for estimating non-specific binding (NSB) in tannin-containing substrates. Non-specific binding values varied widely (0.4-2.8 mg PEG/100 mg DM tannin-free substrate) when the tannin-free substrate was changed from wheat straw to either rye grass or maize shoots. We therefore propose a modified radiolabelled PEG-binding method to estimate the level of PEG-binding (PEGb) to tannin-containing foliage without using tannin-free substrate to correct for non-specific binding. In this approach, incremental levels of each tanniniferous substrate were used to generate PEGb values. The resultant linear response was analysed and tannin activity was expressed as the slope of the response curve (PEGbSlope) observed for each substrate. The slope takes into account the non-specific binding in each substrate, thus PEGbSlope does not require correction for NSB using tannin-free samples. This approach improved the correlation between PEGb and the 125 I-labelled bovine serum albumin precipitation assay. Relationships between the modified PEG-binding assay and radiolabelled bovine serum albumin assay, in vitro tannin bioassay and colorimetric assays are presented. (author)

  19. Multimedia Pivot Tables for Multimedia Analytics on Image Collections

    OpenAIRE

    Worring, M.; Koelma, D.; Zahálka, J.

    2016-01-01

    We propose a multimedia analytics solution for getting insight into image collections by extending the powerful analytic capabilities of pivot tables, found in the ubiquitous spreadsheets, to multimedia. We formalize the concept of multimedia pivot tables and give design rules and methods for the multimodal summarization, structuring, and browsing of the collection based on these tables, all optimized to support an analyst in getting structural and conclusive insights. Our proposed solution p...

  20. Tipping solutions: emerging 3D nano-fabrication/ -imaging technologies

    Directory of Open Access Journals (Sweden)

    Seniutinas Gediminas

    2017-06-01

    Full Text Available The evolution of optical microscopy from an imaging technique into a tool for materials modification and fabrication is now being repeated with other characterization techniques, including scanning electron microscopy (SEM, focused ion beam (FIB milling/imaging, and atomic force microscopy (AFM. Fabrication and in situ imaging of materials undergoing a three-dimensional (3D nano-structuring within a 1−100 nm resolution window is required for future manufacturing of devices. This level of precision is critically in enabling the cross-over between different device platforms (e.g. from electronics to micro-/nano-fluidics and/or photonics within future devices that will be interfacing with biological and molecular systems in a 3D fashion. Prospective trends in electron, ion, and nano-tip based fabrication techniques are presented.

  1. Browsing and Querying in Online Documentation:A Study of User Interfaces and the Interaction Process

    DEFF Research Database (Denmark)

    Hertzum, Morten; Frøkjær, Erik

    1996-01-01

    A user interface study concerning the usage effectiveness of selected retrieval modes was conducted using an experimental text retrieval system, TeSS, giving access to online documentation of certain programming tools. Four modes of TeSS were compared: (1) browsing, (2) conventional boolean....... In the experiment the use of printed manuals is faster and provides answers of higher quality than any of the electronic modes. Therefore, claims about the effectiveness of computer-based text retrieval have to be wary in situations where printed manuals are manageable to the users. Among the modes of Te......SS, browsing is the fastest and the one causing fewest operational errors. On the same two variables, time and operational errors, the Venn diagram mode performs better than conventional boolean retrieval. The combined mode scores worst on the objective performance measures; nonetheless nearly all subjects...

  2. Atlas of PET/MR imaging in oncology

    International Nuclear Information System (INIS)

    Ratib, Osman; Schwaiger, Markus; Beyer, Thomas

    2013-01-01

    Numerous illustrated clinical cases in different oncology domains. Includes digital interactive software matching the cases in the book. Interactive version based on the latest web standard, HTML5, ensuring the widest compatibility. Edited by three international opinion leaders/imaging experts in the field. This new project on PET/MR imaging in oncology includes digital interactive software matching the cases in the book. The interactive version of the atlas is based on the latest web standard, HTML5, ensuring compatibility with any computer operating system as well as a dedicated version for Apple iPad and iPhone. The book opens with an introduction to the principles of hybrid imaging that pays particular attention to PET/MR imaging and standard PET/MR acquisition protocols. A wide range of illustrated clinical case reports are then presented. Each case study includes a short clinical history, findings, and teaching points, followed by illustrations, legends, and comments. The multimedia version of the book includes dynamic movies that allow the reader to browse through series of rotating 3D images (MIP or volume rendered), display blending between PET and MR, and dynamic visualization of 3D image volumes. The movies can be played either continuously or sequentially for better exploration of sets of images. The editors of this state-of-the-art publication are key opinion leaders in the field of multimodality imaging. Professor Osman Ratib (Geneva) and Professor Markus Schwaiger (Munich) were the first in Europe to initiate the clinical adoption of PET/MR imaging. Professor Thomas Beyer (Zurich) is an internationally renowned pioneering physicist in the field of hybrid imaging. Individual clinical cases presented in this book are co-authored by leading international radiologists and nuclear physicians experts in the use of PET and MRI.

  3. Atlas of PET/MR imaging in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Ratib, Osman [University Hospital of Geneva (Switzerland). Nuclear Medicine Division; Schwaiger, Markus [Technische Univ. Muenchen (Germany). Nuklearmedizinische Klinik und Poliklinik; Beyer, Thomas (eds.) [General Hospital Vienna (Austria). Center for Medical Physics and Biomedical Engineering

    2013-08-01

    Numerous illustrated clinical cases in different oncology domains. Includes digital interactive software matching the cases in the book. Interactive version based on the latest web standard, HTML5, ensuring the widest compatibility. Edited by three international opinion leaders/imaging experts in the field. This new project on PET/MR imaging in oncology includes digital interactive software matching the cases in the book. The interactive version of the atlas is based on the latest web standard, HTML5, ensuring compatibility with any computer operating system as well as a dedicated version for Apple iPad and iPhone. The book opens with an introduction to the principles of hybrid imaging that pays particular attention to PET/MR imaging and standard PET/MR acquisition protocols. A wide range of illustrated clinical case reports are then presented. Each case study includes a short clinical history, findings, and teaching points, followed by illustrations, legends, and comments. The multimedia version of the book includes dynamic movies that allow the reader to browse through series of rotating 3D images (MIP or volume rendered), display blending between PET and MR, and dynamic visualization of 3D image volumes. The movies can be played either continuously or sequentially for better exploration of sets of images. The editors of this state-of-the-art publication are key opinion leaders in the field of multimodality imaging. Professor Osman Ratib (Geneva) and Professor Markus Schwaiger (Munich) were the first in Europe to initiate the clinical adoption of PET/MR imaging. Professor Thomas Beyer (Zurich) is an internationally renowned pioneering physicist in the field of hybrid imaging. Individual clinical cases presented in this book are co-authored by leading international radiologists and nuclear physicians experts in the use of PET and MRI.

  4. Browsing the fusion data in a Google map way

    International Nuclear Information System (INIS)

    Song, Xianming; Pan, W.; Chen, L.; Song, Xiao; Pan, L.; Luo, C.; Zhang, G.

    2015-01-01

    Full text of publication follows. How to access the ITER data is still an open issue. Concepts from KSTAR(1), W7X(2), EAST(3), and DIIID(4) have been presented. In this paper, a new web application to browse the fusion data in a Google map way is demonstrated on HL-2A database. This dynamic and interactive web application can run in any popular browser(IE, safari, Firefox, Opera), by any hardware (smart phone, PC, ipad, Mac) and operating system (ios, android, windows, linux, Mac OS). No any plug-ins is needed. The details of the framework for this web application are presented. The framework consists of three layers. The front top client layer is developed by Jquery code. The middle layer, which plays a role of a bridge to connect the server and client is developed by PHP code. The behind server layer is developed by Matlab, which responses any command from the front top client, retrieves the data from the HL-2A database, analyses and processes the data, and finally, returns the data to the client in client's favorite way. The way to browse and retrieve the fusion data is well welcomed by many researchers who access fusion data from many other machines. This way may apply to other machines, and present useful idea to the way for accessing ITER data in the future. References: 1) Kim, E.N., Web-based (HTML5) Interactive Graphics for Fusion Research and Collaboration, O4-2, 8. IAEA Technical Meeting on Control, Data Acquisition and Remote Participation for Fusion Research. June 20-24,2011, San Francisco, CA; 2)Davis, W.M., Easy Web Interfaces to IDL Code for NSTX Data Analysis Progress on Standardization and Automation in Software Development on W7X, P2-1. 8. IAEA Technical Meeting on Control, Data Acquisition and Remote Participation for Fusion Research. June 20-24,2011, San Francisco, CA; 3) Yang, F., A Web Based MDSPLUS Data Analysis and Visualization System for EAST, P2-16. 8th IAEA Technical Meeting on Control, Data Acquisition and Remote Participation for

  5. Browse Title Index

    African Journals Online (AJOL)

    Items 351 - 400 of 879 ... Vol 21, No 4 (2007), Humanising education through technology: creating social presence in large classes, Abstract. F C Greyling, A Wentzel ... CL Brown, L Czerniewicz. Vol 23, No 5 (2009), Image and academic expectations of different levels of university students: A South African case, Abstract.

  6. Preparing diagnostic 3D images for image registration with planning CT images

    International Nuclear Information System (INIS)

    Tracton, Gregg S.; Miller, Elizabeth P.; Rosenman, Julian; Chang, Sha X.; Sailer, Scott; Boxwala, Azaz; Chaney, Edward L.

    1997-01-01

    Purpose: Pre-radiotherapy (pre-RT) tomographic images acquired for diagnostic purposes often contain important tumor and/or normal tissue information which is poorly defined or absent in planning CT images. Our two years of clinical experience has shown that computer-assisted 3D registration of pre-RT images with planning CT images often plays an indispensable role in accurate treatment volume definition. Often the only available format of the diagnostic images is film from which the original 3D digital data must be reconstructed. In addition, any digital data, whether reconstructed or not, must be put into a form suitable for incorporation into the treatment planning system. The purpose of this investigation was to identify all problems that must be overcome before this data is suitable for clinical use. Materials and Methods: In the past two years we have 3D-reconstructed 300 diagnostic images from film and digital sources. As a problem was discovered we built a software tool to correct it. In time we collected a large set of such tools and found that they must be applied in a specific order to achieve the correct reconstruction. Finally, a toolkit (ediScan) was built that made all these tools available in the proper manner via a pleasant yet efficient mouse-based user interface. Results: Problems we discovered included different magnifications, shifted display centers, non-parallel image planes, image planes not perpendicular to the long axis of the table-top (shearing), irregularly spaced scans, non contiguous scan volumes, multiple slices per film, different orientations for slice axes (e.g. left-right reversal), slices printed at window settings corresponding to tissues of interest for diagnostic purposes, and printing artifacts. We have learned that the specific steps to correct these problems, in order of application, are: Also, we found that fast feedback and large image capacity (at least 2000 x 2000 12-bit pixels) are essential for practical application

  7. Food Image Recognition via Superpixel Based Low-Level and Mid-Level Distance Coding for Smart Home Applications

    Directory of Open Access Journals (Sweden)

    Jiannan Zheng

    2017-05-01

    Full Text Available Food image recognition is a key enabler for many smart home applications such as smart kitchen and smart personal nutrition log. In order to improve living experience and life quality, smart home systems collect valuable insights of users’ preferences, nutrition intake and health conditions via accurate and robust food image recognition. In addition, efficiency is also a major concern since many smart home applications are deployed on mobile devices where high-end GPUs are not available. In this paper, we investigate compact and efficient food image recognition methods, namely low-level and mid-level approaches. Considering the real application scenario where only limited and noisy data are available, we first proposed a superpixel based Linear Distance Coding (LDC framework where distinctive low-level food image features are extracted to improve performance. On a challenging small food image dataset where only 12 training images are available per category, our framework has shown superior performance in both accuracy and robustness. In addition, to better model deformable food part distribution, we extend LDC’s feature-to-class distance idea and propose a mid-level superpixel food parts-to-class distance mining framework. The proposed framework show superior performance on a benchmark food image datasets compared to other low-level and mid-level approaches in the literature.

  8. Bi-level image compression with tree coding

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1996-01-01

    Presently, tree coders are the best bi-level image coders. The current ISO standard, JBIG, is a good example. By organising code length calculations properly a vast number of possible models (trees) can be investigated within reasonable time prior to generating code. Three general-purpose coders...... are constructed by this principle. A multi-pass free tree coding scheme produces superior compression results for all test images. A multi-pass fast free template coding scheme produces much better results than JBIG for difficult images, such as halftonings. Rissanen's algorithm `Context' is presented in a new...

  9. Mistletoes, their host plants and the effects of browsing by large mammals in Addo Elephant National Park

    Directory of Open Access Journals (Sweden)

    J.J. Midgley

    1991-09-01

    Full Text Available There are at least four plant hemiparasites [=mistletoes, viz. Viscaceae (3 species, Loranthaceae (1 species] within the Addo Elephant National Park. Highly selective utilisation of these plant parasites by large browsing animals has resulted in severe decline of these plants within the elephant enclosure. The parasites are often associated with spinescent host plants. We suggest this has less to do with escaping herbivory by large mammals and more to do with spinescent plants being optimum hosts because they are a richer nutritient source for plant parasites than most non-spinescent plants.

  10. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 189 of 189 ... Vol 3, No 2 (2002), Stability of Anthocyanin Sensitized TiO2 Photoelectrochemical ... Vol 12, No 1 (2012), Supervised color image segmentation, using LVQ ... Vol 3, No 1 (2002), The Fish and Fisheries of the Lower Volta ...

  11. Image accuracy and representational enhancement through low-level, multi-sensor integration techniques

    International Nuclear Information System (INIS)

    Baker, J.E.

    1993-05-01

    Multi-Sensor Integration (MSI) is the combining of data and information from more than one source in order to generate a more reliable and consistent representation of the environment. The need for MSI derives largely from basic ambiguities inherent in our current sensor imaging technologies. These ambiguities exist as long as the mapping from reality to image is not 1-to-1. That is, if different 44 realities'' lead to identical images, a single image cannot reveal the particular reality which was the truth. MSI techniques can be divided into three categories based on the relative information content of the original images with that of the desired representation: (1) ''detail enhancement,'' wherein the relative information content of the original images is less rich than the desired representation; (2) ''data enhancement,'' wherein the MSI techniques axe concerned with improving the accuracy of the data rather than either increasing or decreasing the level of detail; and (3) ''conceptual enhancement,'' wherein the image contains more detail than is desired, making it difficult to easily recognize objects of interest. In conceptual enhancement one must group pixels corresponding to the same conceptual object and thereby reduce the level of extraneous detail. This research focuses on data and conceptual enhancement algorithms. To be useful in many real-world applications, e.g., autonomous or teleoperated robotics, real-time feedback is critical. But, many MSI/image processing algorithms require significant processing time. This is especially true of feature extraction, object isolation, and object recognition algorithms due to their typical reliance on global or large neighborhood information. This research attempts to exploit the speed currently available in state-of-the-art digitizers and highly parallel processing systems by developing MSI algorithms based on pixel rather than global-level features

  12. Antelope bitterbrush reestablishment: a case study of plant size and browse protection effects.

    Science.gov (United States)

    G. Randy Johnson; Joel P. Okula

    2006-01-01

    After an intense stand-replacement fire in south-central Oregon, 1-y-old (1+0) bareroot seedlings of antelope bitterbrush (Purshia tridentata (Pursh) DC. [Rosaceae]) were outplanted over a 4-y period. Paired-plots were established to examine the benefits of protecting the plants from damage due to animal browsing with Vexar mesh tubing. In the first...

  13. Calibration and validation of the {sup 14}C-labelled polyethylene glycol-binding assay for tannins in tropical browse

    Energy Technology Data Exchange (ETDEWEB)

    Mlambo, V. [Animal Production Unit, FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf (Austria)]. E-mail: vmlambo@agric.uniswa.sz; Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division of Nuclear Techniques in Agriculture and Food, International Atomic Energy Agency, Vienna (Austria)

    2005-08-19

    This study evaluates the radiolabelled polyethylene glycol (PEG)-binding procedure [Silanikove, N., Shinder, D., Gilboa, N., Eyal, M., Nitsan, Z., 1996. Polyethylene glycol-binding to plant samples as an assay for the biological effects of tannins: predicting the negative effects of tannins in Mediterranean browse on rumen degradation. J. Agric. Food Chem. 44, 3230-3234] for tannin analysis, using 27 tropical browse plants. In this method, the amount of PEG bound to a plant sample is assumed to be a reflection of its tannin content. The method was modified to exclude the use of non-tanniniferous substrate for estimating non-specific binding (NSB) in tannin-containing substrates. Non-specific binding values varied widely (0.4-2.8 mg PEG/100 mg DM tannin-free substrate) when the tannin-free substrate was changed from wheat straw to either rye grass or maize shoots. We therefore propose a modified radiolabelled PEG-binding method to estimate the level of PEG-binding (PEGb) to tannin-containing foliage without using tannin-free substrate to correct for non-specific binding. In this approach, incremental levels of each tanniniferous substrate were used to generate PEGb values. The resultant linear response was analysed and tannin activity was expressed as the slope of the response curve (PEGbSlope) observed for each substrate. The slope takes into account the non-specific binding in each substrate, thus PEGbSlope does not require correction for NSB using tannin-free samples. This approach improved the correlation between PEGb and the {sup 125}I-labelled bovine serum albumin precipitation assay. Relationships between the modified PEG-binding assay and radiolabelled bovine serum albumin assay, in vitro tannin bioassay and colorimetric assays are presented. (author)

  14. Images crossing borders: image and workflow sharing on multiple levels.

    Science.gov (United States)

    Ross, Peeter; Pohjonen, Hanna

    2011-04-01

    Digitalisation of medical data makes it possible to share images and workflows between related parties. In addition to linear data flow where healthcare professionals or patients are the information carriers, a new type of matrix of many-to-many connections is emerging. Implementation of shared workflow brings challenges of interoperability and legal clarity. Sharing images or workflows can be implemented on different levels with different challenges: inside the organisation, between organisations, across country borders, or between healthcare institutions and citizens. Interoperability issues vary according to the level of sharing and are either technical or semantic, including language. Legal uncertainty increases when crossing national borders. Teleradiology is regulated by multiple European Union (EU) directives and legal documents, which makes interpretation of the legal system complex. To achieve wider use of eHealth and teleradiology several strategic documents were published recently by the EU. Despite EU activities, responsibility for organising, providing and funding healthcare systems remains with the Member States. Therefore, the implementation of new solutions requires strong co-operation between radiologists, societies of radiology, healthcare administrators, politicians and relevant EU authorities. The aim of this article is to describe different dimensions of image and workflow sharing and to analyse legal acts concerning teleradiology in the EU.

  15. Seasonal variations in diet selection of Nguni goats: effects of physical and chemical traits of browse

    CSIR Research Space (South Africa)

    Fomum, SW

    2015-05-01

    Full Text Available Goats select some browse species more than others, given options. Seasonal trends of diet selection of Nguni goats indexed by intake were investigated in cafeteria-style experiments. The relationships between diet selection and plant chemical...

  16. Image-guided regularization level set evolution for MR image segmentation and bias field correction.

    Science.gov (United States)

    Wang, Lingfeng; Pan, Chunhong

    2014-01-01

    Magnetic resonance (MR) image segmentation is a crucial step in surgical and treatment planning. In this paper, we propose a level-set-based segmentation method for MR images with intensity inhomogeneous problem. To tackle the initialization sensitivity problem, we propose a new image-guided regularization to restrict the level set function. The maximum a posteriori inference is adopted to unify segmentation and bias field correction within a single framework. Under this framework, both the contour prior and the bias field prior are fully used. As a result, the image intensity inhomogeneity can be well solved. Extensive experiments are provided to evaluate the proposed method, showing significant improvements in both segmentation and bias field correction accuracies as compared with other state-of-the-art approaches. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. MetaRNA-Seq: An Interactive Tool to Browse and Annotate Metadata from RNA-Seq Studies

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar

    2015-01-01

    Full Text Available The number of RNA-Seq studies has grown in recent years. The design of RNA-Seq studies varies from very simple (e.g., two-condition case-control to very complicated (e.g., time series involving multiple samples at each time point with separate drug treatments. Most of these publically available RNA-Seq studies are deposited in NCBI databases, but their metadata are scattered throughout four different databases: Sequence Read Archive (SRA, Biosample, Bioprojects, and Gene Expression Omnibus (GEO. Although the NCBI web interface is able to provide all of the metadata information, it often requires significant effort to retrieve study- or project-level information by traversing through multiple hyperlinks and going to another page. Moreover, project- and study-level metadata lack manual or automatic curation by categories, such as disease type, time series, case-control, or replicate type, which are vital to comprehending any RNA-Seq study. Here we describe “MetaRNA-Seq,” a new tool for interactively browsing, searching, and annotating RNA-Seq metadata with the capability of semiautomatic curation at the study level.

  18. 18F-FDG PET imaging of rheumatoid knee synovitis correlates with dynamic magnetic resonance and sonographic assessments as well as with the serum level of metalloproteinase-3

    International Nuclear Information System (INIS)

    Beckers, Catherine; Foidart, Jacqueline; Hustinx, Roland; Jeukens, Xavier; Marcelis, Stefaan; Ribbens, Clio; Andre, Beatrice; Leclercq, Philippe; Kaiser, Marie-Joelle; Malaise, Michel G.

    2006-01-01

    The aim of this study was to assess rheumatoid arthritis (RA) synovitis with positron emission tomography (PET) and 18 F-fluorodeoxyglucose ( 18 F-FDG) in comparison with dynamic magnetic resonance imaging (MRI) and ultrasonography (US). Sixteen knees in 16 patients with active RA were assessed with PET, MRI and US at baseline and 4 weeks after initiation of anti-TNF-α treatment. All studies were performed within 4 days. Visual and semi-quantitative (standardised uptake value, SUV) analyses of the synovial uptake of FDG were performed. The dynamic enhancement rate and the static enhancement were measured after i.v. gadolinium injection and the synovial thickness was measured in the medial, lateral patellar and suprapatellar recesses by US. Serum levels of C-reactive protein (CRP) and metalloproteinase-3 (MMP-3) were also measured. PET was positive in 69% of knees while MRI and US were positive in 69% and 75%. Positivity on one imaging technique was strongly associated with positivity on the other two. PET-positive knees exhibited significantly higher SUVs, higher MRI parameters and greater synovial thickness compared with PET-negative knees, whereas serum CRP and MMP-3 levels were not significantly different. SUVs were significantly correlated with all MRI parameters, with synovial thickness and with serum CRP and MMP-3 levels at baseline. Changes in SUVs after 4 weeks were also correlated with changes in MRI parameters and in serum CRP and MMP-3 levels, but not with changes in synovial thickness. (orig.)

  19. Automatic segmentation of MRI head images by 3-D region growing method which utilizes edge information

    International Nuclear Information System (INIS)

    Jiang, Hao; Suzuki, Hidetomo; Toriwaki, Jun-ichiro

    1991-01-01

    This paper presents a 3-D segmentation method that automatically extracts soft tissue from multi-sliced MRI head images. MRI produces a sequence of two-dimensional (2-D) images which contains three-dimensional (3-D) information of organs. To utilize such information we need effective algorithms to treat 3-D digital images and to extract organs and tissues of interest. We developed a method to extract the brain from MRI images which uses a region growing procedure and integrates information of uniformity of gray levels and information of the presence of edge segments in the local area around the pixel of interest. First we generate a kernel region which is a part of brain tissue by simple thresholding. Then we grow the region by means of a region growing algorithm under the control of 3-D edge existence to obtain the region of the brain. Our method is rather simple because it uses basic 3-D image processing techniques like spatial difference. It is robust for variation of gray levels inside a tissue since it also refers to the edge information in the process of region growing. Therefore, the method is flexible enough to be applicable to the segmentation of other images including soft tissues which have complicated shapes and fluctuation in gray levels. (author)

  20. Measurable realistic image-based 3D mapping

    Science.gov (United States)

    Liu, W.; Wang, J.; Wang, J. J.; Ding, W.; Almagbile, A.

    2011-12-01

    Maps with 3D visual models are becoming a remarkable feature of 3D map services. High-resolution image data is obtained for the construction of 3D visualized models.The3D map not only provides the capabilities of 3D measurements and knowledge mining, but also provides the virtual experienceof places of interest, such as demonstrated in the Google Earth. Applications of 3D maps are expanding into the areas of architecture, property management, and urban environment monitoring. However, the reconstruction of high quality 3D models is time consuming, and requires robust hardware and powerful software to handle the enormous amount of data. This is especially for automatic implementation of 3D models and the representation of complicated surfacesthat still need improvements with in the visualisation techniques. The shortcoming of 3D model-based maps is the limitation of detailed coverage since a user can only view and measure objects that are already modelled in the virtual environment. This paper proposes and demonstrates a 3D map concept that is realistic and image-based, that enables geometric measurements and geo-location services. Additionally, image-based 3D maps provide more detailed information of the real world than 3D model-based maps. The image-based 3D maps use geo-referenced stereo images or panoramic images. The geometric relationships between objects in the images can be resolved from the geometric model of stereo images. The panoramic function makes 3D maps more interactive with users but also creates an interesting immersive circumstance. Actually, unmeasurable image-based 3D maps already exist, such as Google street view, but only provide virtual experiences in terms of photos. The topographic and terrain attributes, such as shapes and heights though are omitted. This paper also discusses the potential for using a low cost land Mobile Mapping System (MMS) to implement realistic image 3D mapping, and evaluates the positioning accuracy that a measureable

  1. Mapping urban impervious surface using object-based image analysis with WorldView-3 satellite imagery

    Science.gov (United States)

    Iabchoon, Sanwit; Wongsai, Sangdao; Chankon, Kanoksuk

    2017-10-01

    Land use and land cover (LULC) data are important to monitor and assess environmental change. LULC classification using satellite images is a method widely used on a global and local scale. Especially, urban areas that have various LULC types are important components of the urban landscape and ecosystem. This study aims to classify urban LULC using WorldView-3 (WV-3) very high-spatial resolution satellite imagery and the object-based image analysis method. A decision rules set was applied to classify the WV-3 images in Kathu subdistrict, Phuket province, Thailand. The main steps were as follows: (1) the image was ortho-rectified with ground control points and using the digital elevation model, (2) multiscale image segmentation was applied to divide the image pixel level into image object level, (3) development of the decision ruleset for LULC classification using spectral bands, spectral indices, spatial and contextual information, and (4) accuracy assessment was computed using testing data, which sampled by statistical random sampling. The results show that seven LULC classes (water, vegetation, open space, road, residential, building, and bare soil) were successfully classified with overall classification accuracy of 94.14% and a kappa coefficient of 92.91%.

  2. 3D vector flow imaging

    DEFF Research Database (Denmark)

    Pihl, Michael Johannes

    The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... are (vx, vy, vz) = (-0.03, 95, 1.0) ± (9, 6, 1) cm/s compared with the expected (0, 96, 0) cm/s. Afterwards, 3D vector flow images from a cross-sectional plane of the vessel are presented. The out of plane velocities exhibit the expected 2D circular-symmetric parabolic shape. The experimental results...... verify that the 3D TO method estimates the complete 3D velocity vectors, and that the method is suitable for 3D vector flow imaging....

  3. The effect of drying and urea treatment on nutritional and anti-nutritional components of browses collected during wet and dry seasons

    Energy Technology Data Exchange (ETDEWEB)

    Vitti, D.M.S.S. [Centre for Nuclear Energy in Agriculture, University of Sao Paulo, Piracicaba, SP (Brazil)]. E-mail: dovitti@cena.usp.br; Nozella, E.F.; Abdalla, A.L.; Bueno, I.C.S.; Longo, C.; Cabral Filho, S.L.S.; Godoy, P.B. [Centre for Nuclear Energy in Agriculture, University of Sao Paulo, Piracicaba, SP (Brazil); Silva Filho, J.C. [Universidade Federal de Lavras, Lavras, MG (Brazil); Costa, C. [Faculdade de Medicina Veterinaria e Zootecnia, UNESP, Botucatu, SP (Brazil); Bueno, M.S. [Instituto de Zootecnia, Nova Odessa, SP (Brazil); Vieira, M.E.Q. [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil); Mueller-Harvey, I. [Agriculture Department, University of Reading, Reading (United Kingdom)

    2005-08-19

    Fibre, crude protein and tannin concentrations were measured in browse species from the semi-arid region of Northeast Brazil during the dry and wet seasons. The effects of oven-, sun- and shade-drying and of urea treatment were also determined. Crude protein (CP) content varied from 103 to 161 g/kg dry matter (DM) and the browses had similar CP content in the two seasons (during 2002) (102-161 and 107-153 g/kg DM in the wet and dry seasons, respectively). Total tannin concentrations ranged from 13 to 201 g/kg DM amongst the browses and were higher in the dry season. A 30-d treatment with urea reduced extractable tannins significantly (P < 0.05). The urea treatment was also most effective at reducing the in vitro effects of tannins compared to the other drying treatments. This was demonstrated by measuring the effect of polyethylene glycol (PEG) on gas production. Addition of PEG increased gas production of oven- (81.4%), sun- (78.5%) and shade-dried (76.7%) samples much more compared to urea treated samples (10.9%). (author)

  4. The effect of drying and urea treatment on nutritional and anti-nutritional components of browses collected during wet and dry seasons

    International Nuclear Information System (INIS)

    Vitti, D.M.S.S.; Nozella, E.F.; Abdalla, A.L.; Bueno, I.C.S.; Longo, C.; Cabral Filho, S.L.S.; Godoy, P.B.; Silva Filho, J.C.; Costa, C.; Bueno, M.S.; Vieira, M.E.Q.; Mueller-Harvey, I.

    2005-01-01

    Fibre, crude protein and tannin concentrations were measured in browse species from the semi-arid region of Northeast Brazil during the dry and wet seasons. The effects of oven-, sun- and shade-drying and of urea treatment were also determined. Crude protein (CP) content varied from 103 to 161 g/kg dry matter (DM) and the browses had similar CP content in the two seasons (during 2002) (102-161 and 107-153 g/kg DM in the wet and dry seasons, respectively). Total tannin concentrations ranged from 13 to 201 g/kg DM amongst the browses and were higher in the dry season. A 30-d treatment with urea reduced extractable tannins significantly (P < 0.05). The urea treatment was also most effective at reducing the in vitro effects of tannins compared to the other drying treatments. This was demonstrated by measuring the effect of polyethylene glycol (PEG) on gas production. Addition of PEG increased gas production of oven- (81.4%), sun- (78.5%) and shade-dried (76.7%) samples much more compared to urea treated samples (10.9%). (author)

  5. Influence of mineral nutrition on susceptibility and recovery of planted seedlings of ungulate browse

    Science.gov (United States)

    Owen T. Burney; Douglass F. Jacobs

    2010-01-01

    Efforts to minimize animal damage during reforestation in the Oregon Coast Range have had little success. Enhancing plant mineral nutrition via application of controlled-release fertilization at the time of planting may provide some relief from ungulate browse pressure due to increased height growth, but associated impacts on susceptibility of fertilized plants to...

  6. Evaluation of polynomial image deformation for matching of 3D- abdominal MR-images using anatomical landmarks and for atlas construction

    CERN Document Server

    Kimiaei, S; Jonsson, E; Crafoord, J; Maguire, G Q

    1999-01-01

    The aim of this study is to compare and evaluate the potential usability of linear and non-linear (polynomial) 3D-warping for constructing an atlas by matching abdominal MR-images from a number of different individuals using manually picked anatomical landmarks. The significance of this study lies in the fact that it illustrates the potential to use polynomial matching at a local or organ level. This is a necessary requirement for constructing an atlas and for fine intra-patient image matching and fusion. Finally 3D-image warping using anatomical landmark for inter-patient intra-modality image co-registration and fusion was found to be a very powerful and robust method. Additionally it can be used for intra-patient inter- modality image matching.

  7. Conceptual Web Users' Actions Prediction for Ontology-Based Browsing Recommendations

    Science.gov (United States)

    Robal, Tarmo; Kalja, Ahto

    The Internet consists of thousands of web sites with different kinds of structures. However, users are browsing the web according to their informational expectations towards the web site searched, having an implicit conceptual model of the domain in their minds. Nevertheless, people tend to repeat themselves and have partially shared conceptual views while surfing the web, finding some areas of web sites more interesting than others. Herein, we take advantage of the latter and provide a model and a study on predicting users' actions based on the web ontology concepts and their relations.

  8. 3D images and expert system

    International Nuclear Information System (INIS)

    Hasegawa, Jun-ichi

    1998-01-01

    This paper presents an expert system called 3D-IMPRESS for supporting applications of three dimensional (3D) image processing. This system can automatically construct a 3D image processing procedure based on a pictorial example of the goal given by a user. In the paper, to evaluate the performance of the system, it was applied to construction of procedures for extracting specific component figures from practical chest X-ray CT images. (author)

  9. A Symmetric Chaos-Based Image Cipher with an Improved Bit-Level Permutation Strategy

    Directory of Open Access Journals (Sweden)

    Chong Fu

    2014-02-01

    Full Text Available Very recently, several chaos-based image ciphers using a bit-level permutation have been suggested and shown promising results. Due to the diffusion effect introduced in the permutation stage, the workload of the time-consuming diffusion stage is reduced, and hence the performance of the cryptosystem is improved. In this paper, a symmetric chaos-based image cipher with a 3D cat map-based spatial bit-level permutation strategy is proposed. Compared with those recently proposed bit-level permutation methods, the diffusion effect of the new method is superior as the bits are shuffled among different bit-planes rather than within the same bit-plane. Moreover, the diffusion key stream extracted from hyperchaotic system is related to both the secret key and the plain image, which enhances the security against known/chosen plaintext attack. Extensive security analysis has been performed on the proposed scheme, including the most important ones like key space analysis, key sensitivity analysis, plaintext sensitivity analysis and various statistical analyses, which has demonstrated the satisfactory security of the proposed scheme

  10. Construction of Realistic Liver Phantoms from Patient Images using 3D Printer and Its Application in CT Image Quality Assessment.

    Science.gov (United States)

    Leng, Shuai; Yu, Lifeng; Vrieze, Thomas; Kuhlmann, Joel; Chen, Baiyu; McCollough, Cynthia H

    2015-01-01

    The purpose of this study is to use 3D printing techniques to construct a realistic liver phantom with heterogeneous background and anatomic structures from patient CT images, and to use the phantom to assess image quality with filtered backprojection and iterative reconstruction algorithms. Patient CT images were segmented into liver tissues, contrast-enhanced vessels, and liver lesions using commercial software, based on which stereolithography (STL) files were created and sent to a commercial 3D printer. A 3D liver phantom was printed after assigning different printing materials to each object to simulate appropriate attenuation of each segmented object. As high opacity materials are not available for the printer, we printed hollow vessels and filled them with iodine solutions of adjusted concentration to represent enhance levels in contrast-enhanced liver scans. The printed phantom was then placed in a 35×26 cm oblong-shaped water phantom and scanned repeatedly at 4 dose levels. Images were reconstructed using standard filtered backprojection and an iterative reconstruction algorithm with 3 different strength settings. Heterogeneous liver background were observed from the CT images and the difference in CT numbers between lesions and background were representative for low contrast lesions in liver CT studies. CT numbers in vessels filled with iodine solutions represented the enhancement of liver arteries and veins. Images were run through a Channelized Hotelling model observer with Garbor channels and ROC analysis was performed. The AUC values showed performance improvement using the iterative reconstruction algorithm and the amount of improvement increased with strength setting.

  11. 3D segmentation of scintigraphic images with validation on realistic GATE simulations

    International Nuclear Information System (INIS)

    Burg, Samuel

    2011-01-01

    The objective of this thesis was to propose a new 3D segmentation method for scintigraphic imaging. The first part of the work was to simulate 3D volumes with known ground truth in order to validate a segmentation method over other. Monte-Carlo simulations were performed using the GATE software (Geant4 Application for Emission Tomography). For this, we characterized and modeled the gamma camera 'γ Imager' Biospace"T"M by comparing each measurement from a simulated acquisition to his real equivalent. The 'low level' segmentation tool that we have developed is based on a modeling of the levels of the image by probabilistic mixtures. Parameters estimation is done by an SEM algorithm (Stochastic Expectation Maximization). The 3D volume segmentation is achieved by an ICM algorithm (Iterative Conditional Mode). We compared the segmentation based on Gaussian and Poisson mixtures to segmentation by thresholding on the simulated volumes. This showed the relevance of the segmentations obtained using probabilistic mixtures, especially those obtained with Poisson mixtures. Those one has been used to segment real "1"8FDG PET images of the brain and to compute descriptive statistics of the different tissues. In order to obtain a 'high level' segmentation method and find anatomical structures (necrotic part or active part of a tumor, for example), we proposed a process based on the point processes formalism. A feasibility study has yielded very encouraging results. (author) [fr

  12. The effect of base image window level selection on the dimensional measurement accuracy of resultant three-dimensional image displays

    International Nuclear Information System (INIS)

    Kurmis, A.P.; Hearn, T.C.; Reynolds, K.J.

    2003-01-01

    Purpose: The aim of this study was to determine the effect of base image window level selection on direct linear measurement of knee structures displayed using new magnetic resonance (MR)-based three-dimensional reconstructed computer imaging techniques. Methods: A prospective comparative study was performed using a series of three-dimensional knee images, generated from conventional MR imaging (MRI) sections. Thirty distinct anatomical structural features were identified within the image series of which repeated measurements were compared at 10 different window grey scale levels. Results: Statistical analysis demonstrated an excellent raw correlation between measurements and suggested no significant difference between measurements made at each of the 10 window level settings (P>0.05). Conclusions: The findings of this study suggest that unlike conventional MR or CT applications, grey scale window level selection at the time of imaging does not significantly affect the visual quality of resultant three-dimensional reconstructed images and hence the accuracy of subsequent direct linear measurement. The diagnostic potential of clinical progression from routine two-dimensional to advanced three-dimensional reconstructed imaging techniques may therefore be less likely to be degraded by inappropriate MR technician image windowing during the capturing of image series

  13. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, A.K.; Bow, W.J.; Strong, D.S. [and others

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  14. 3D composite image, 3D MRI, 3D SPECT, hydrocephalus

    International Nuclear Information System (INIS)

    Mito, T.; Shibata, I.; Sugo, N.; Takano, M.; Takahashi, H.

    2002-01-01

    The three-dimensional (3D)SPECT imaging technique we have studied and published for the past several years is an analytical tool that permits visual expression of the cerebral circulation profile in various cerebral diseases. The greatest drawback of SPECT is that the limitation on precision of spacial resolution makes intracranial localization impossible. In 3D SPECT imaging, intracranial volume and morphology may vary with the threshold established. To solve this problem, we have produced complimentarily combined SPECT and helical-CT 3D images by means of general-purpose visualization software for intracranial localization. In hydrocephalus, however, the key subject to be studied is the profile of cerebral circulation around the ventricles of the brain. This suggests that, for displaying the cerebral ventricles in three dimensions, CT is a difficult technique whereas MRI is more useful. For this reason, we attempted to establish the profile of cerebral circulation around the cerebral ventricles by the production of combined 3D images of SPECT and MRI. In patients who had shunt surgery for hydrocephalus, a difference between pre- and postoperative cerebral circulation profiles was assessed by a voxel distribution curve, 3D SPECT images, and combined 3D SPECT and MRI images. As the shunt system in this study, an Orbis-Sigma valve of the automatic cerebrospinal fluid volume adjustment type was used in place of the variable pressure type Medos valve currently in use, because this device requires frequent changes in pressure and a change in pressure may be detected after MRI procedure. The SPECT apparatus used was PRISM3000 of the three-detector type, and 123I-IMP was used as the radionuclide in a dose of 222 MBq. MRI data were collected with an MAGNEXa+2 with a magnetic flux density of 0.5 tesla under the following conditions: field echo; TR 50 msec; TE, 10 msec; flip, 30ueK; 1 NEX; FOV, 23 cm; 1-mm slices; and gapless. 3D images are produced on the workstation TITAN

  15. Web-Browsing Competencies of Pre-Service Adult Facilitators: Implications for Curriculum Transformation and Distance Learning

    Science.gov (United States)

    Theresa, Ofoegbu; Ugwu, Agboeze Matthias; Ihebuzoaju, Anyanwu Joy; Uche, Asogwa

    2013-01-01

    The study investigated the Web-browsing competencies of pre-service adult facilitators in the southeast geopolitical zone of Nigeria. Survey design was adopted for the study. The population consists of all pre-service adult facilitators in all the federal universities in the southeast geopolitical zone of Nigeria. Accidental sampling technique was…

  16. The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul; Lim, Tae Hwan; Kang, Weechang

    2002-01-01

    To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

  17. A new level set model for cell image segmentation

    Science.gov (United States)

    Ma, Jing-Feng; Hou, Kai; Bao, Shang-Lian; Chen, Chun

    2011-02-01

    In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing.

  18. Effect of blood glucose level on 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Tan Haibo; Lin Xiangtong; Guan Yihui; Zhao Jun; Zuo Chuantao; Hua Fengchun; Tang Wenying

    2008-01-01

    Objective: The aim of this study was to investigate the effect of blood glucose level on the image quality of 18 F-fluorodeoxyglucose (FDG) PET/CT imaging. Methods: Eighty patients referred to the authors' department for routine whole-body 18 F-FDG PET/CT check up were recruited into this study. The patients were classified into 9 groups according to their blood glucose level: normal group avg and SUV max ) of liver on different slices. SPSS 12.0 was used to analyse the data. Results: (1) There were significant differences among the 9 groups in image quality scores and image noises (all P avg and SUV max : 0.60 and 0.33, P<0.05). Conclusions: The higher the blood glucose level, the worse the image quality. When the blood glucose level is more than or equal to 12.0 mmol/L, the image quality will significantly degrade. (authors)

  19. Modeling And Simulation Of Multimedia Communication Networks

    Science.gov (United States)

    Vallee, Richard; Orozco-Barbosa, Luis; Georganas, Nicolas D.

    1989-05-01

    In this paper, we present a simulation study of a browsing system involving radiological image servers. The proposed IEEE 802.6 DQDB MAN standard is designated as the computer network to transfer radiological images from file servers to medical workstations, and to simultaneously support real time voice communications. Storage and transmission of original raster scanned images and images compressed according to pyramid data structures are considered. Different types of browsing as well as various image sizes and bit rates in the DQDB MAN are also compared. The elapsed time, measured from the time an image request is issued until the image is displayed on the monitor, is the parameter considered to evaluate the system performance. Simulation results show that image browsing can be supported by the DQDB MAN.

  20. MilxXplore: a web-based system to explore large imaging datasets.

    Science.gov (United States)

    Bourgeat, P; Dore, V; Villemagne, V L; Rowe, C C; Salvado, O; Fripp, J

    2013-01-01

    As large-scale medical imaging studies are becoming more common, there is an increasing reliance on automated software to extract quantitative information from these images. As the size of the cohorts keeps increasing with large studies, there is a also a need for tools that allow results from automated image processing and analysis to be presented in a way that enables fast and efficient quality checking, tagging and reporting on cases in which automatic processing failed or was problematic. MilxXplore is an open source visualization platform, which provides an interface to navigate and explore imaging data in a web browser, giving the end user the opportunity to perform quality control and reporting in a user friendly, collaborative and efficient way. Compared to existing software solutions that often provide an overview of the results at the subject's level, MilxXplore pools the results of individual subjects and time points together, allowing easy and efficient navigation and browsing through the different acquisitions of a subject over time, and comparing the results against the rest of the population. MilxXplore is fast, flexible and allows remote quality checks of processed imaging data, facilitating data sharing and collaboration across multiple locations, and can be easily integrated into a cloud computing pipeline. With the growing trend of open data and open science, such a tool will become increasingly important to share and publish results of imaging analysis.

  1. Automatic adjustment of display window (gray-level condition) for MR images using neural networks

    International Nuclear Information System (INIS)

    Ohhashi, Akinami; Nambu, Kyojiro.

    1992-01-01

    We have developed a system to automatically adjust the display window width and level (WWL) for MR images using neural networks. There were three main points in the development of our system as follows: 1) We defined an index for the clarity of a displayed image, and called 'EW'. EW is a quantitative measure of the clarity of an image displayed in a certain WWL, and can be derived from the difference between gray-level with the WWL adjusted by a human expert and with a certain WWL. 2) We extracted a group of six features from a gray-level histogram of a displayed image. We designed two neural networks which are able to learn the relationship between these features and the desired output (teaching signal), 'EQ', which is normalized to 0 to 1.0 from EW. Two neural networks were used to share the patterns to be learned; one learns a variety of patterns with less accuracy, and the other learns similar patterns with accuracy. Learning was performed using a back-propagation method. As a result, the neural networks after learning are able to provide a quantitative measure, 'Q', of the clarity of images displayed in the designated WWL. 3) Using the 'Hill climbing' method, we have been able to determine the best possible WWL for a displaying image. We have tested this technique for MR brain images. The results show that this system can adjust WWL comparable to that adjusted by a human expert for the majority of test images. The neural network is effective for the automatic adjustment of the display window for MR images. We are now studying the application of this method to MR images of another regions. (author)

  2. Texture Feature Analysis for Different Resolution Level of Kidney Ultrasound Images

    Science.gov (United States)

    Kairuddin, Wan Nur Hafsha Wan; Mahmud, Wan Mahani Hafizah Wan

    2017-08-01

    Image feature extraction is a technique to identify the characteristic of the image. The objective of this work is to discover the texture features that best describe a tissue characteristic of a healthy kidney from ultrasound (US) image. Three ultrasound machines that have different specifications are used in order to get a different quality (different resolution) of the image. Initially, the acquired images are pre-processed to de-noise the speckle to ensure the image preserve the pixels in a region of interest (ROI) for further extraction. Gaussian Low- pass Filter is chosen as the filtering method in this work. 150 of enhanced images then are segmented by creating a foreground and background of image where the mask is created to eliminate some unwanted intensity values. Statistical based texture features method is used namely Intensity Histogram (IH), Gray-Level Co-Occurance Matrix (GLCM) and Gray-level run-length matrix (GLRLM).This method is depends on the spatial distribution of intensity values or gray levels in the kidney region. By using One-Way ANOVA in SPSS, the result indicated that three features (Contrast, Difference Variance and Inverse Difference Moment Normalized) from GLCM are not statistically significant; this concludes that these three features describe a healthy kidney characteristics regardless of the ultrasound image quality.

  3. Accuracy of volume measurement using 3D ultrasound and development of CT-3D US image fusion algorithm for prostate cancer radiotherapy

    International Nuclear Information System (INIS)

    Baek, Jihye; Huh, Jangyoung; Hyun An, So; Oh, Yoonjin; Kim, Myungsoo; Kim, DongYoung; Chung, Kwangzoo; Cho, Sungho; Lee, Rena

    2013-01-01

    Purpose: To evaluate the accuracy of measuring volumes using three-dimensional ultrasound (3D US), and to verify the feasibility of the replacement of CT-MR fusion images with CT-3D US in radiotherapy treatment planning. Methods: Phantoms, consisting of water, contrast agent, and agarose, were manufactured. The volume was measured using 3D US, CT, and MR devices. A CT-3D US and MR-3D US image fusion software was developed using the Insight Toolkit library in order to acquire three-dimensional fusion images. The quality of the image fusion was evaluated using metric value and fusion images. Results: Volume measurement, using 3D US, shows a 2.8 ± 1.5% error, 4.4 ± 3.0% error for CT, and 3.1 ± 2.0% error for MR. The results imply that volume measurement using the 3D US devices has a similar accuracy level to that of CT and MR. Three-dimensional image fusion of CT-3D US and MR-3D US was successfully performed using phantom images. Moreover, MR-3D US image fusion was performed using human bladder images. Conclusions: 3D US could be used in the volume measurement of human bladders and prostates. CT-3D US image fusion could be used in monitoring the target position in each fraction of external beam radiation therapy. Moreover, the feasibility of replacing the CT-MR image fusion to the CT-3D US in radiotherapy treatment planning was verified.

  4. Comparative study between the radiopacity levels of high viscosity and of flowable composite resins, using digital imaging.

    Science.gov (United States)

    Arita, Emiko S; Silveira, Gilson P; Cortes, Arthur R; Brucoli, Henrique C

    2012-01-01

    The development of countless types and trends of high viscosite and flowable composite resins, with different physical and chemical properties applicable to their broad use in dental clinics calls for further studies regarding their radiopacity level. The aim of this study was to evaluate the radiopacity levels of high viscosity and the flowable composite resins, using digital imaging. 96 composite resin discs 5 mm in diameter and 3 mm thick were radiographed and analyzed. The image acquisition system used was the Digora® Phosphor Storage System and the images were analyzed with the Digora software for Windows. The exposure conditions were: 70 kVp, 8 mA, and 0.2 s. The focal distance was 40 cm. The image densities were obtained with the pixel values of the materials in the digital image. Most of the high viscosity composite resins presented higher radiopacity levels than the flowable composite resins, with statistically significant differences between the trends and groups analyzed (P composite resins, Tetric®Ceram presented the highest radiopacity levels and Glacier® presented the lowest. Among the flowable composite resins, Tetric®Flow presented the highest radiopacity levels and Wave® presented the lowest.

  5. 3D Texture Analysis in Renal Cell Carcinoma Tissue Image Grading

    Science.gov (United States)

    Cho, Nam-Hoon; Choi, Heung-Kook

    2014-01-01

    One of the most significant processes in cancer cell and tissue image analysis is the efficient extraction of features for grading purposes. This research applied two types of three-dimensional texture analysis methods to the extraction of feature values from renal cell carcinoma tissue images, and then evaluated the validity of the methods statistically through grade classification. First, we used a confocal laser scanning microscope to obtain image slices of four grades of renal cell carcinoma, which were then reconstructed into 3D volumes. Next, we extracted quantitative values using a 3D gray level cooccurrence matrix (GLCM) and a 3D wavelet based on two types of basis functions. To evaluate their validity, we predefined 6 different statistical classifiers and applied these to the extracted feature sets. In the grade classification results, 3D Haar wavelet texture features combined with principal component analysis showed the best discrimination results. Classification using 3D wavelet texture features was significantly better than 3D GLCM, suggesting that the former has potential for use in a computer-based grading system. PMID:25371701

  6. 3D Texture Analysis in Renal Cell Carcinoma Tissue Image Grading

    Directory of Open Access Journals (Sweden)

    Tae-Yun Kim

    2014-01-01

    Full Text Available One of the most significant processes in cancer cell and tissue image analysis is the efficient extraction of features for grading purposes. This research applied two types of three-dimensional texture analysis methods to the extraction of feature values from renal cell carcinoma tissue images, and then evaluated the validity of the methods statistically through grade classification. First, we used a confocal laser scanning microscope to obtain image slices of four grades of renal cell carcinoma, which were then reconstructed into 3D volumes. Next, we extracted quantitative values using a 3D gray level cooccurrence matrix (GLCM and a 3D wavelet based on two types of basis functions. To evaluate their validity, we predefined 6 different statistical classifiers and applied these to the extracted feature sets. In the grade classification results, 3D Haar wavelet texture features combined with principal component analysis showed the best discrimination results. Classification using 3D wavelet texture features was significantly better than 3D GLCM, suggesting that the former has potential for use in a computer-based grading system.

  7. The imaging 3.0 informatics scorecard.

    Science.gov (United States)

    Kohli, Marc; Dreyer, Keith J; Geis, J Raymond

    2015-04-01

    Imaging 3.0 is a radiology community initiative to empower radiologists to create and demonstrate value for their patients, referring physicians, and health systems. In image-guided health care, radiologists contribute to the entire health care process, well before and after the actual examination, and out to the point at which they guide clinical decisions and affect patient outcome. Because imaging is so pervasive, radiologists who adopt Imaging 3.0 concepts in their practice can help their health care systems provide consistently high-quality care at reduced cost. By doing this, radiologists become more valuable in the new health care setting. The authors describe how informatics is critical to embracing Imaging 3.0 and present a scorecard that can be used to gauge a radiology group's informatics resources and capabilities. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  8. The Algorithm Theoretical Basis Document for Level 1A Processing

    Science.gov (United States)

    Jester, Peggy L.; Hancock, David W., III

    2012-01-01

    The first process of the Geoscience Laser Altimeter System (GLAS) Science Algorithm Software converts the Level 0 data into the Level 1A Data Products. The Level 1A Data Products are the time ordered instrument data converted from counts to engineering units. This document defines the equations that convert the raw instrument data into engineering units. Required scale factors, bias values, and coefficients are defined in this document. Additionally, required quality assurance and browse products are defined in this document.

  9. Image quality assessment of LaBr3-based whole-body 3D PET scanners: a Monte Carlo evaluation

    International Nuclear Information System (INIS)

    Surti, S; Karp, J S; Muehllehner, G

    2004-01-01

    The main thrust for this work is the investigation and design of a whole-body PET scanner based on new lanthanum bromide scintillators. We use Monte Carlo simulations to generate data for a 3D PET scanner based on LaBr 3 detectors, and to assess the count-rate capability and the reconstructed image quality of phantoms with hot and cold spheres using contrast and noise parameters. Previously we have shown that LaBr 3 has very high light output, excellent energy resolution and fast timing properties which can lead to the design of a time-of-flight (TOF) whole-body PET camera. The data presented here illustrate the performance of LaBr 3 without the additional benefit of TOF information, although our intention is to develop a scanner with TOF measurement capability. The only drawbacks of LaBr 3 are the lower stopping power and photo-fraction which affect both sensitivity and spatial resolution. However, in 3D PET imaging where energy resolution is very important for reducing scattered coincidences in the reconstructed image, the image quality attained in a non-TOF LaBr 3 scanner can potentially equal or surpass that achieved with other high sensitivity scanners. Our results show that there is a gain in NEC arising from the reduced scatter and random fractions in a LaBr 3 scanner. The reconstructed image resolution is slightly worse than a high-Z scintillator, but at increased count-rates, reduced pulse pileup leads to an image resolution similar to that of LSO. Image quality simulations predict reduced contrast for small hot spheres compared to an LSO scanner, but improved noise characteristics at similar clinical activity levels

  10. Image quality enhancement in low-light-level ghost imaging using modified compressive sensing method

    Science.gov (United States)

    Shi, Xiaohui; Huang, Xianwei; Nan, Suqin; Li, Hengxing; Bai, Yanfeng; Fu, Xiquan

    2018-04-01

    Detector noise has a significantly negative impact on ghost imaging at low light levels, especially for existing recovery algorithm. Based on the characteristics of the additive detector noise, a method named modified compressive sensing ghost imaging is proposed to reduce the background imposed by the randomly distributed detector noise at signal path. Experimental results show that, with an appropriate choice of threshold value, modified compressive sensing ghost imaging algorithm can dramatically enhance the contrast-to-noise ratio of the object reconstruction significantly compared with traditional ghost imaging and compressive sensing ghost imaging methods. The relationship between the contrast-to-noise ratio of the reconstruction image and the intensity ratio (namely, the average signal intensity to average noise intensity ratio) for the three reconstruction algorithms are also discussed. This noise suppression imaging technique will have great applications in remote-sensing and security areas.

  11. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 100 of 2157 ... TS Brand, WJ Kritzinger, LC Hoffman, RM Gous ... Vol 10, No 2 (1980): Symposium, A marketing and promotion strategy for wool .... Vol 36, No 3 (2006), A preliminary study on the application of image analysis for the ...

  12. A new level set model for cell image segmentation

    International Nuclear Information System (INIS)

    Ma Jing-Feng; Chen Chun; Hou Kai; Bao Shang-Lian

    2011-01-01

    In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing. (cross-disciplinary physics and related areas of science and technology)

  13. Internet use, browsing, and the urban poor: implications for cancer control.

    Science.gov (United States)

    Viswanath, K; McCloud, Rachel; Minsky, Sara; Puleo, Elaine; Kontos, Emily; Bigman-Galimore, Cabral; Rudd, Rima; Emmons, Karen M

    2013-12-01

    Despite the growing penetration of the Internet, little is known about the usage and browsing patterns of those in poverty. We report on a randomized controlled trial that sheds light on the Internet use and browsing patterns among the urban poor. The data come from 312 participants in Boston, Massachusetts, from Click to Connect, a study that examined the impact of an intervention that provided computers, Internet, and training to people from lower socioeconomic position (SEP). Data were gathered through pre- and posttest surveys and Internet use tracking software that generated approximately 13 million network activity files and more than 5.5 million records. Internet use increased among intervention participants, with most of their time spent on social and participatory media sites or Internet portals. Differential patterns of use by gender and race/ethnicity were observed. Purposive searching for health information was low among all participants. Most of the visits to health-related sites were to local hospitals' sites suggesting the influence of possible preexisting relationships and trust. Social networking sites were frequently visited, with three sites enjoying similar popularity among all groups. Our data show that the availability of Internet can lead to significant increase in its use among low SEP groups. Low SEP members used the Internet for participation and engagement, but the sites visited differed by group. Harnessing the power of social networking sites and shareware sites may be a way to increase access to health information.

  14. Nonlaser-based 3D surface imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  15. Estimation of regional lung expansion via 3D image registration

    Science.gov (United States)

    Pan, Yan; Kumar, Dinesh; Hoffman, Eric A.; Christensen, Gary E.; McLennan, Geoffrey; Song, Joo Hyun; Ross, Alan; Simon, Brett A.; Reinhardt, Joseph M.

    2005-04-01

    A method is described to estimate regional lung expansion and related biomechanical parameters using multiple CT images of the lungs, acquired at different inflation levels. In this study, the lungs of two sheep were imaged utilizing a multi-detector row CT at different lung inflations in the prone and supine positions. Using the lung surfaces and the airway branch points for guidance, a 3D inverse consistent image registration procedure was used to match different lung volumes at each orientation. The registration was validated using a set of implanted metal markers. After registration, the Jacobian of the deformation field was computed to express regional expansion or contraction. The regional lung expansion at different pressures and different orientations are compared.

  16. Adaptive fringe-pattern projection for image saturation avoidance in 3D surface-shape measurement.

    Science.gov (United States)

    Li, Dong; Kofman, Jonathan

    2014-04-21

    In fringe-projection 3D surface-shape measurement, image saturation results in incorrect intensities in captured images of fringe patterns, leading to phase and measurement errors. An adaptive fringe-pattern projection (AFPP) method was developed to adapt the maximum input gray level in projected fringe patterns to the local reflectivity of an object surface being measured. The AFPP method demonstrated improved 3D measurement accuracy by avoiding image saturation in highly-reflective surface regions while maintaining high intensity modulation across the entire surface. The AFPP method can avoid image saturation and handle varying surface reflectivity, using only two prior rounds of fringe-pattern projection and image capture to generate the adapted fringe patterns.

  17. Imaging chemical reactions - 3D velocity mapping

    Science.gov (United States)

    Chichinin, A. I.; Gericke, K.-H.; Kauczok, S.; Maul, C.

    Visualising a collision between an atom or a molecule or a photodissociation (half-collision) of a molecule on a single particle and single quantum level is like watching the collision of billiard balls on a pool table: Molecular beams or monoenergetic photodissociation products provide the colliding reactants at controlled velocity before the reaction products velocity is imaged directly with an elaborate camera system, where one should keep in mind that velocity is, in general, a three-dimensional (3D) vectorial property which combines scattering angles and speed. If the processes under study have no cylindrical symmetry, then only this 3D product velocity vector contains the full information of the elementary process under study.

  18. Development of an omnidirectional gamma-ray imaging Compton camera for low-radiation-level environmental monitoring

    Science.gov (United States)

    Watanabe, Takara; Enomoto, Ryoji; Muraishi, Hiroshi; Katagiri, Hideaki; Kagaya, Mika; Fukushi, Masahiro; Kano, Daisuke; Satoh, Wataru; Takeda, Tohoru; Tanaka, Manobu M.; Tanaka, Souichi; Uchida, Tomohisa; Wada, Kiyoto; Wakamatsu, Ryo

    2018-02-01

    We have developed an omnidirectional gamma-ray imaging Compton camera for environmental monitoring at low levels of radiation. The camera consisted of only six CsI(Tl) scintillator cubes of 3.5 cm, each of which was readout by super-bialkali photo-multiplier tubes (PMTs). Our camera enables the visualization of the position of gamma-ray sources in all directions (∼4π sr) over a wide energy range between 300 and 1400 keV. The angular resolution (σ) was found to be ∼11°, which was realized using an image-sharpening technique. A high detection efficiency of 18 cps/(µSv/h) for 511 keV (1.6 cps/MBq at 1 m) was achieved, indicating the capability of this camera to visualize hotspots in areas with low-radiation-level contamination from the order of µSv/h to natural background levels. Our proposed technique can be easily used as a low-radiation-level imaging monitor in radiation control areas, such as medical and accelerator facilities.

  19. Low-level processing for real-time image analysis

    Science.gov (United States)

    Eskenazi, R.; Wilf, J. M.

    1979-01-01

    A system that detects object outlines in television images in real time is described. A high-speed pipeline processor transforms the raw image into an edge map and a microprocessor, which is integrated into the system, clusters the edges, and represents them as chain codes. Image statistics, useful for higher level tasks such as pattern recognition, are computed by the microprocessor. Peak intensity and peak gradient values are extracted within a programmable window and are used for iris and focus control. The algorithms implemented in hardware and the pipeline processor architecture are described. The strategy for partitioning functions in the pipeline was chosen to make the implementation modular. The microprocessor interface allows flexible and adaptive control of the feature extraction process. The software algorithms for clustering edge segments, creating chain codes, and computing image statistics are also discussed. A strategy for real time image analysis that uses this system is given.

  20. High-accuracy and real-time 3D positioning, tracking system for medical imaging applications based on 3D digital image correlation

    Science.gov (United States)

    Xue, Yuan; Cheng, Teng; Xu, Xiaohai; Gao, Zeren; Li, Qianqian; Liu, Xiaojing; Wang, Xing; Song, Rui; Ju, Xiangyang; Zhang, Qingchuan

    2017-01-01

    This paper presents a system for positioning markers and tracking the pose of a rigid object with 6 degrees of freedom in real-time using 3D digital image correlation, with two examples for medical imaging applications. Traditional DIC method was improved to meet the requirements of the real-time by simplifying the computations of integral pixel search. Experiments were carried out and the results indicated that the new method improved the computational efficiency by about 4-10 times in comparison with the traditional DIC method. The system was aimed for orthognathic surgery navigation in order to track the maxilla segment after LeFort I osteotomy. Experiments showed noise for the static point was at the level of 10-3 mm and the measurement accuracy was 0.009 mm. The system was demonstrated on skin surface shape evaluation of a hand for finger stretching exercises, which indicated a great potential on tracking muscle and skin movements.

  1. Rainbow Particle Imaging Velocimetry for Dense 3D Fluid Velocity Imaging

    KAUST Repository

    Xiong, Jinhui

    2017-04-11

    Despite significant recent progress, dense, time-resolved imaging of complex, non-stationary 3D flow velocities remains an elusive goal. In this work we tackle this problem by extending an established 2D method, Particle Imaging Velocimetry, to three dimensions by encoding depth into color. The encoding is achieved by illuminating the flow volume with a continuum of light planes (a “rainbow”), such that each depth corresponds to a specific wavelength of light. A diffractive component in the camera optics ensures that all planes are in focus simultaneously. For reconstruction, we derive an image formation model for recovering stationary 3D particle positions. 3D velocity estimation is achieved with a variant of 3D optical flow that accounts for both physical constraints as well as the rainbow image formation model. We evaluate our method with both simulations and an experimental prototype setup.

  2. Quantitative myocardial perfusion PET parametric imaging at the voxel-level

    International Nuclear Information System (INIS)

    Mohy-ud-Din, Hassan; Rahmim, Arman; Lodge, Martin A

    2015-01-01

    Quantitative myocardial perfusion (MP) PET has the potential to enhance detection of early stages of atherosclerosis or microvascular dysfunction, characterization of flow-limiting effects of coronary artery disease (CAD), and identification of balanced reduction of flow due to multivessel stenosis. We aim to enable quantitative MP-PET at the individual voxel level, which has the potential to allow enhanced visualization and quantification of myocardial blood flow (MBF) and flow reserve (MFR) as computed from uptake parametric images. This framework is especially challenging for the 82 Rb radiotracer. The short half-life enables fast serial imaging and high patient throughput; yet, the acquired dynamic PET images suffer from high noise-levels introducing large variability in uptake parametric images and, therefore, in the estimates of MBF and MFR. Robust estimation requires substantial post-smoothing of noisy data, degrading valuable functional information of physiological and pathological importance. We present a feasible and robust approach to generate parametric images at the voxel-level that substantially reduces noise without significant loss of spatial resolution. The proposed methodology, denoted physiological clustering, makes use of the functional similarity of voxels to penalize deviation of voxel kinetics from physiological partners. The results were validated using extensive simulations (with transmural and non-transmural perfusion defects) and clinical studies. Compared to post-smoothing, physiological clustering depicted enhanced quantitative noise versus bias performance as well as superior recovery of perfusion defects (as quantified by CNR) with minimal increase in bias. Overall, parametric images obtained from the proposed methodology were robust in the presence of high-noise levels as manifested in the voxel time-activity-curves. (paper)

  3. Selecting optimal monochromatic level with spectral CT imaging for improving imaging quality in hepatic venography

    International Nuclear Information System (INIS)

    Sun Jun; Luo Xianfu; Wang Shou'an; Wang Jun; Sun Jiquan; Wang Zhijun; Wu Jingtao

    2013-01-01

    Objective: To investigate the effect of spectral CT monochromatic images for improving imaging quality in hepatic venography. Methods: Thirty patients underwent spectral CT examination on a GE Discovery CT 750 HD scanner. During portal phase, 1.25 mm slice thickness polychromatic images and optimal monochromatic images were obtained, and volume rendering and maximum intensity projection were created to show the hepatic veins respectively. The overall imaging quality was evaluated on a five-point scale by two radiologists. Inter-observer agreement in subjective image quality grading was assessed by Kappa statistics. Paired-sample t test were used to compare hepatic vein attenuation, hepatic parenchyma attenuation, CT value difference between the hepatic vein and the liver parenchyma, image noise, vein-to-liver contrast-to-noise ratio (CNR), the image quality score of hepatic venography between the two image data sets. Results: The monochromatic images at 50 keV were found to demonstrate the best CNR for hepatic vein.The hepatic vein attenuation [(329 ± 47) HU], hepatic parenchyma attenuation [(178 ± 33) HU], CT value difference between the hepatic vein and the liver parenchyma [(151 ± 33) HU], image noise (17.33 ± 4.18), CNR (9.13 ± 2.65), the image quality score (4.2 ± 0.6) of optimal monochromatic images were significantly higher than those of polychromatic images [(149 ± 18) HU], [(107 ± 14) HU], [(43 ±11) HU], 12.55 ± 3.02, 3.53 ± 1.03, 3.1 ± 0.8 (t values were 24.79, 13.95, 18.85, 9.07, 13.25 and 12.04, respectively, P < 0.01). In the comparison of image quality, Kappa value was 0.81 with optimal monochromatic images and 0.69 with polychromatic images. Conclusion: Monochromatic images of spectral CT could improve CNR for displaying hepatic vein and improve the image quality compared to the conventional polychromatic images. (authors)

  4. On the limitations and optimisation of high-resolution 3D medical X-ray imaging systems

    International Nuclear Information System (INIS)

    Zhou Shuang; Brahme, Anders

    2011-01-01

    Based on a quantitative analysis of both attenuation and refractive properties of X-ray propagation in human body tissues and the introduction of a mathematical model for image quality analysis, some limitations and optimisation of high-resolution three-dimensional (3D) medical X-ray imaging techniques are studied. A comparison is made of conventional attenuation-based X-ray imaging methods with the phase-contrast X-ray imaging modalities that have been developed recently. The results indicate that it is theoretically possible through optimal design of the X-ray imaging system to achieve high spatial resolution (<100 μm) in 3D medical X-ray imaging of the human body at a clinically acceptable dose level (<10 mGy) by introducing a phase-contrast X-ray imaging technique.

  5. Lossless, Near-Lossless, and Refinement Coding of Bi-level Images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren Otto

    1997-01-01

    We present general and unified algorithms for lossy/lossless codingof bi-level images. The compression is realized by applying arithmetic coding to conditional probabilities. As in the current JBIG standard the conditioning may be specified by a template.For better compression, the more general....... Introducing only a small amount of loss in halftoned test images, compression is increased by up to a factor of four compared with JBIG. Lossy, lossless, and refinement decoding speed and lossless encoding speed are less than a factor of two slower than JBIG. The (de)coding method is proposed as part of JBIG......-2, an emerging international standard for lossless/lossy compression of bi-level images....

  6. Soft tissue segmentation and 3D display from computerized tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Fan, R.T.; Trivedi, S.S.; Fellingham, L.L.; Gamboa-Aldeco, A.; Hedgcock, M.W.

    1987-01-01

    Volume calculation and 3D display of human anatomy facilitate a physician's diagnosis, treatment, and evaluation. Accurate segmentation of soft tissue structures is a prerequisite for such volume calculations and 3D displays, but segmentation by hand-outlining structures is often tedious and time-consuming. In this paper, methods based on analysis of statistics of image gray level are applied to segmentation of soft tissue in medical images, with the goal of making segmentation automatic or semi-automatic. The resulting segmented images, volume calculations, and 3D displays are analyzed and compared with results based on physician-drawn outlines as well as actual volume measurements

  7. A Variational Level Set Model Combined with FCMS for Image Clustering Segmentation

    Directory of Open Access Journals (Sweden)

    Liming Tang

    2014-01-01

    Full Text Available The fuzzy C means clustering algorithm with spatial constraint (FCMS is effective for image segmentation. However, it lacks essential smoothing constraints to the cluster boundaries and enough robustness to the noise. Samson et al. proposed a variational level set model for image clustering segmentation, which can get the smooth cluster boundaries and closed cluster regions due to the use of level set scheme. However it is very sensitive to the noise since it is actually a hard C means clustering model. In this paper, based on Samson’s work, we propose a new variational level set model combined with FCMS for image clustering segmentation. Compared with FCMS clustering, the proposed model can get smooth cluster boundaries and closed cluster regions due to the use of level set scheme. In addition, a block-based energy is incorporated into the energy functional, which enables the proposed model to be more robust to the noise than FCMS clustering and Samson’s model. Some experiments on the synthetic and real images are performed to assess the performance of the proposed model. Compared with some classical image segmentation models, the proposed model has a better performance for the images contaminated by different noise levels.

  8. 3-D image reconstruction in radiology

    International Nuclear Information System (INIS)

    Grangeat, P.

    1999-01-01

    In this course, we present highlights on fully 3-D image reconstruction algorithms used in 3-D X-ray Computed Tomography (3-D-CT) and 3-D Rotational Radiography (3-D-RR). We first consider the case of spiral CT with a one-row detector. Starting from the 2-D fan-beam inversion formula for a circular trajectory, we introduce spiral CT 3-D image reconstruction algorithm using axial interpolation for each transverse slice. In order to improve the X-ray detection efficiency and to speed the acquisition process, the future is to use multi-row detectors associated with small angle cone-beam geometry. The generalization of the 2-D fan-beam image reconstruction algorithm to cone beam defined direct inversion formula referred as Feldkamp's algorithm for a circular trajectory and Wang's algorithm for a spiral trajectory. However, large area detectors does exist such as Radiological Image Intensifiers or in a near future solid state detectors. To get a larger zoom effect, it defines a cone-beam geometry associated with a large aperture angle. For this case, we introduce indirect image reconstruction algorithm by plane re-binning in the Radon domain. We will present some results from a prototype MORPHOMETER device using the RADON reconstruction software. Lastly, we consider the special case of 3-D Rotational Digital Subtraction Angiography with a restricted number of views. We introduce constraint optimization algorithm using quadratic, entropic or half-quadratic constraints. Generalized ART (Algebraic Reconstruction Technique) iterative reconstruction algorithm can be derived from the Bregman algorithm. We present reconstructed vascular trees from a prototype MORPHOMETER device. (author)

  9. Indium-111 labeled leukocyte images demonstrating a lung abscess with prominent fluid level

    International Nuclear Information System (INIS)

    Massie, J.D.; Winer-Muram, H.

    1986-01-01

    In-111 labeled leukocyte images show an abscess cavity with a fluid level on 24-hour upright images. Fluid levels, frequently seen on radiographs, are uncommon on nuclear images. This finding demonstrates rapid migration of labeled leukocytes into purulent abscess fluid

  10. Synergistic Instance-Level Subspace Alignment for Fine-Grained Sketch-Based Image Retrieval.

    Science.gov (United States)

    Li, Ke; Pang, Kaiyue; Song, Yi-Zhe; Hospedales, Timothy M; Xiang, Tao; Zhang, Honggang

    2017-08-25

    We study the problem of fine-grained sketch-based image retrieval. By performing instance-level (rather than category-level) retrieval, it embodies a timely and practical application, particularly with the ubiquitous availability of touchscreens. Three factors contribute to the challenging nature of the problem: (i) free-hand sketches are inherently abstract and iconic, making visual comparisons with photos difficult, (ii) sketches and photos are in two different visual domains, i.e. black and white lines vs. color pixels, and (iii) fine-grained distinctions are especially challenging when executed across domain and abstraction-level. To address these challenges, we propose to bridge the image-sketch gap both at the high-level via parts and attributes, as well as at the low-level, via introducing a new domain alignment method. More specifically, (i) we contribute a dataset with 304 photos and 912 sketches, where each sketch and image is annotated with its semantic parts and associated part-level attributes. With the help of this dataset, we investigate (ii) how strongly-supervised deformable part-based models can be learned that subsequently enable automatic detection of part-level attributes, and provide pose-aligned sketch-image comparisons. To reduce the sketch-image gap when comparing low-level features, we also (iii) propose a novel method for instance-level domain-alignment, that exploits both subspace and instance-level cues to better align the domains. Finally (iv) these are combined in a matching framework integrating aligned low-level features, mid-level geometric structure and high-level semantic attributes. Extensive experiments conducted on our new dataset demonstrate effectiveness of the proposed method.

  11. Extracting 3D Parametric Curves from 2D Images of Helical Objects.

    Science.gov (United States)

    Willcocks, Chris G; Jackson, Philip T G; Nelson, Carl J; Obara, Boguslaw

    2017-09-01

    Helical objects occur in medicine, biology, cosmetics, nanotechnology, and engineering. Extracting a 3D parametric curve from a 2D image of a helical object has many practical applications, in particular being able to extract metrics such as tortuosity, frequency, and pitch. We present a method that is able to straighten the image object and derive a robust 3D helical curve from peaks in the object boundary. The algorithm has a small number of stable parameters that require little tuning, and the curve is validated against both synthetic and real-world data. The results show that the extracted 3D curve comes within close Hausdorff distance to the ground truth, and has near identical tortuosity for helical objects with a circular profile. Parameter insensitivity and robustness against high levels of image noise are demonstrated thoroughly and quantitatively.

  12. Interactive browsing of 3D environment over the Internet

    Science.gov (United States)

    Zhang, Cha; Li, Jin

    2000-12-01

    In this paper, we describe a system for wandering in a realistic environment over the Internet. The environment is captured by the concentric mosaic, compressed via the reference block coder (RBC), and accessed and delivered over the Internet through the virtual media (Vmedia) access protocol. Capturing the environment through the concentric mosaic is easy. We mount a camera at the end of a level beam, and shoot images as the beam rotates. The huge dataset of the concentric mosaic is then compressed through the RBC, which is specifically designed for both high compression efficiency and just-in-time (JIT) rendering. Through the JIT rendering function, only a portion of the RBC bitstream is accessed, decoded and rendered for each virtual view. A multimedia communication protocol -- the Vmedia protocol, is then proposed to deliver the compressed concentric mosaic data over the Internet. Only the bitstream segments corresponding to the current view are streamed over the Internet. Moreover, the delivered bitstream segments are managed by a local Vmedia cache so that frequently used bitstream segments need not be streamed over the Internet repeatedly, and the Vmedia is able to handle a RBC bitstream larger than its memory capacity. A Vmedia concentric mosaic interactive browser is developed where the user can freely wander in a realistic environment, e.g., rotate around, walk forward/backward and sidestep, even under a tight bandwidth of 33.6 kbps.

  13. Storing, Browsing, Querying, and Sharing Data: the THREDDS Data Repository (TDR)

    Science.gov (United States)

    Wilson, A.; Lindholm, D.; Baltzer, T.

    2005-12-01

    The Unidata Internet Data Distribution (IDD) network delivers gigabytes of data per day in near real time to sites across the U.S. and beyond. The THREDDS Data Server (TDS) supports public browsing of metadata and data access via OPeNDAP enabled URLs for datasets such as these. With such large quantities of data, sites generally employ a simple data management policy, keeping the data for a relatively short term on the order of hours to perhaps a week or two. In order to save interesting data in longer term storage and make it available for sharing, a user must move the data herself. In this case the user is responsible for determining where space is available, executing the data movement, generating any desired metadata, and setting access control to enable sharing. This task sequence is generally based on execution of a sequence of low level operating system specific commands with significant user involvement. The LEAD (Linked Environments for Atmospheric Discovery) project is building a cyberinfrastructure to support research and education in mesoscale meteorology. LEAD orchestrations require large, robust, and reliable storage with speedy access to stage data and store both intermediate and final results. These requirements suggest storage solutions that involve distributed storage, replication, and interfacing to archival storage systems such as mass storage systems and tape or removable disks. LEAD requirements also include metadata generation and access in order to support querying. In support of both THREDDS and LEAD requirements, Unidata is designing and prototyping the THREDDS Data Repository (TDR), a framework for a modular data repository to support distributed data storage and retrieval using a variety of back end storage media and interchangeable software components. The TDR interface will provide high level abstractions for long term storage, controlled, fast and reliable access, and data movement capabilities via a variety of technologies such as

  14. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 346 ... Vol 5, No 3 (2008), Home Management Of Diarrhea Among Underfives In A Rural Community In Kenya: Household Perceptions And Practices, Abstract ... Vol 8, No 2 (2011), Influence of Percieved body Image on Nutrient Intake and Nutritional Health of Female Students of Moi University, Abstract.

  15. Coding of Depth Images for 3DTV

    DEFF Research Database (Denmark)

    Zamarin, Marco; Forchhammer, Søren

    In this short paper a brief overview of the topic of coding and compression of depth images for multi-view image and video coding is provided. Depth images represent a convenient way to describe distances in the 3D scene, useful for 3D video processing purposes. Standard approaches...... for the compression of depth images are described and compared against some recent specialized algorithms able to achieve higher compression performances. Future research directions close the paper....

  16. Communication and Reception in Teaching: The Age of Image Versus the „Weight” of Words

    Directory of Open Access Journals (Sweden)

    Bradea Adela

    2015-12-01

    Full Text Available Contemporary culture is mainly a culture of image. We get our information seeing. Examination of images is free, while reading is impelled by the necessity of browsing the whole text. The image seems more appropriate than the text when trying to communicate easy and quickly. The speech calls for articulated language, expressed through a symbolic set of oral or written codes that we must master. Understanding an image requires less work and fewer skills than reading a text. This paper aims to highlight how messages are perceived and received within the educational activities, through the two types of communication, iconic and logical-linguistic. The instrument used in conducting the research was represented by a questionnaire consisting from objective and subjective items, applied to students from high schools in Oradea. Besides these questionnaires, a key role in the study was played by the knowledge gained while observing lessons held by students of the University of Oradea within their teaching placement, as well as while supervising teachers from secondary educational institutions in the process of obtaining teacher certification level 1. The obtained results prove that the majority of investigated students prefer the combination of two types of communication in teaching.

  17. Comparing different maize supplementation strategies to improve resilience and resistance against gastrointestinal nematode infections in browsing goats.

    Science.gov (United States)

    Gárate-Gallardo, Leslie; Torres-Acosta, Juan Felipe de Jesús; Aguilar-Caballero, Armando Jacinto; Sandoval-Castro, Carlos Alfredo; Cámara-Sarmiento, Ramón; Canul-Ku, Hilda Lorena

    2015-01-01

    The effect of maize grain supplementation on the resilience and resistance of browsing Criollo goat kids against gastrointestinal nematodes was evaluated. Five-month-old kids (n = 42), raised worm-free, were allocated to five groups: infected + not supplemented (I-NS; n = 10), infected + maize supplement at 108 g/d (I-S108; n = 8), maize supplement at 1% of body weight (BW) (I-S1%; n = 8), maize supplement at 1.5% BW (I-S1.5%; n = 8), or infected + supplemented (maize supplement 1.5% BW) + moxidectin (0.2 mg/kg BW subcutaneously every 28 d) (T-S1.5%; n = 8). Kids browsed daily (7 h) in a tropical forest for 112 days during the rainy season. Kids were weighed weekly to adjust supplementary feeding. Hematocrit (Ht), hemoglobin (Hb), and eggs per gram of feces were determined fortnightly. On day 112, five goat kids were slaughtered per group to determine worm burdens. Kids of the I-S1.5% group showed similar body-weight change, Ht and Hb, compared to kids without gastrointestinal nematodes (T-S1.5%), as well as lower eggs per gram of feces and Trichostrongylus colubriformis worm burden compared to the I-NS group (P > 0.05). Thus, among the supplement levels tested, increasing maize supplementation at 1.5% BW of kids was the best strategy to improve their resilience and resistance against natural gastrointestinal nematode infections under the conditions of forage from the tropical forest. © L. Gárate-Gallardo et al., published by EDP Sciences, 2015.

  18. Jekyll or Hyde? Better browse securely

    CERN Multimedia

    Computer Security Team

    2013-01-01

    Surfing the web is like walking through London in 1886. Usually you meet nice Dr Jekyll, interact with him and everything is fine. But at other times, at night, you might encounter the malicious Mr Hyde. He just wants your money and your secrets, and wants to take advantage of you.   As in the novel by Stevenson, good and bad web pages can be very close together. Most web pages exist to provide information or a service. But one click away, one Google page down, there are malicious web pages that aim to steal your password, infect your computer, or lull you into disclosing personal information.    So remember: “STOP - THINK - CLICK!” should be the standard when browsing the Internet. If you are presented with a link that looks strange or contains gibberish (like http://211.268.156.277/.PayPal/cgi-bin/wbscrcmd_login.php), just ignore it! It is always better to type simple, comprehensible web addresses like “www.paypal.com” than...

  19. Teaching People and Machines to Enhance Images

    Science.gov (United States)

    Berthouzoz, Floraine Sara Martianne

    tutorials based on their command-level structure. Sites such as tutorialized.com or good-tutorials.com collect tens of thousands of photo manipulation tutorials. These collections typically contain many different tutorials for the same task. For example, there are many different tutorials that describe how to recolor the hair of a person in an image. Learners often want to compare these tutorials to understand the different ways a task can be done. They may also want to identify common strategies that are used across tutorials for a variety of tasks. However, the large number of tutorials in these collections and their inconsistent formats can make it difficult for users to systematically explore and compare them. Current tutorial collections do not exploit the underlying command-level structure of tutorials, and to explore the collection users have to either page through long lists of tutorial titles or perform keyword searches on the natural language tutorial text. We present a new browsing interface to help learners navigate, explore and compare collections of photo manipulation tutorials based on their command-level structure. Our browser indexes tutorials by their commands, identifies common strategies within the tutorial collection, and highlights the similarities and differences between sets of tutorials that execute the same task. User feedback suggests that our interface is easy to understand and use, and that users find command-level browsing to be useful for exploring large tutorial collections. They strongly preferred to explore tutorial collections with our browser over keyword search. Finally, we present a framework for generating content-adaptive macros (programs) that can transfer complex photo manipulation procedures to new target images. After learners master a photo manipulation procedure, they often repeatedly apply it to multiple images. For example, they might routinely apply the same vignetting effect to all their photographs. This process can be very

  20. Level set method for image segmentation based on moment competition

    Science.gov (United States)

    Min, Hai; Wang, Xiao-Feng; Huang, De-Shuang; Jin, Jing; Wang, Hong-Zhi; Li, Hai

    2015-05-01

    We propose a level set method for image segmentation which introduces the moment competition and weakly supervised information into the energy functional construction. Different from the region-based level set methods which use force competition, the moment competition is adopted to drive the contour evolution. Here, a so-called three-point labeling scheme is proposed to manually label three independent points (weakly supervised information) on the image. Then the intensity differences between the three points and the unlabeled pixels are used to construct the force arms for each image pixel. The corresponding force is generated from the global statistical information of a region-based method and weighted by the force arm. As a result, the moment can be constructed and incorporated into the energy functional to drive the evolving contour to approach the object boundary. In our method, the force arm can take full advantage of the three-point labeling scheme to constrain the moment competition. Additionally, the global statistical information and weakly supervised information are successfully integrated, which makes the proposed method more robust than traditional methods for initial contour placement and parameter setting. Experimental results with performance analysis also show the superiority of the proposed method on segmenting different types of complicated images, such as noisy images, three-phase images, images with intensity inhomogeneity, and texture images.

  1. An Information Foraging Analysis of Note Taking and Note Sharing While Browsing Campaign Information

    DEFF Research Database (Denmark)

    Vatrapu, Ravi; Robertson, Scott

    2010-01-01

    In this paper, we present an experimental study of political information foraging in the context of e-voting. Participants were observed while searching and browsing the internet for campaign information in a mock-voting situation in three online note-taking conditions: No Notes, Private Notes...... with lack of scent, low value perception, and value depletion of information. Implications for the voter centered design of e-voting portals are discussed....

  2. Toward accurate tooth segmentation from computed tomography images using a hybrid level set model

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Yangzhou; Zhao, Qunfei [Department of Automation, Shanghai Jiao Tong University, and Key Laboratory of System Control and Information Processing, Ministry of Education of China, Shanghai 200240 (China); Xia, Zeyang, E-mail: zy.xia@siat.ac.cn, E-mail: jing.xiong@siat.ac.cn; Hu, Ying [Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, and The Chinese University of Hong Kong, Shenzhen 518055 (China); Xiong, Jing, E-mail: zy.xia@siat.ac.cn, E-mail: jing.xiong@siat.ac.cn [Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 510855 (China); Zhang, Jianwei [TAMS, Department of Informatics, University of Hamburg, Hamburg 22527 (Germany)

    2015-01-15

    Purpose: A three-dimensional (3D) model of the teeth provides important information for orthodontic diagnosis and treatment planning. Tooth segmentation is an essential step in generating the 3D digital model from computed tomography (CT) images. The aim of this study is to develop an accurate and efficient tooth segmentation method from CT images. Methods: The 3D dental CT volumetric images are segmented slice by slice in a two-dimensional (2D) transverse plane. The 2D segmentation is composed of a manual initialization step and an automatic slice by slice segmentation step. In the manual initialization step, the user manually picks a starting slice and selects a seed point for each tooth in this slice. In the automatic slice segmentation step, a developed hybrid level set model is applied to segment tooth contours from each slice. Tooth contour propagation strategy is employed to initialize the level set function automatically. Cone beam CT (CBCT) images of two subjects were used to tune the parameters. Images of 16 additional subjects were used to validate the performance of the method. Volume overlap metrics and surface distance metrics were adopted to assess the segmentation accuracy quantitatively. The volume overlap metrics were volume difference (VD, mm{sup 3}) and Dice similarity coefficient (DSC, %). The surface distance metrics were average symmetric surface distance (ASSD, mm), RMS (root mean square) symmetric surface distance (RMSSSD, mm), and maximum symmetric surface distance (MSSD, mm). Computation time was recorded to assess the efficiency. The performance of the proposed method has been compared with two state-of-the-art methods. Results: For the tested CBCT images, the VD, DSC, ASSD, RMSSSD, and MSSD for the incisor were 38.16 ± 12.94 mm{sup 3}, 88.82 ± 2.14%, 0.29 ± 0.03 mm, 0.32 ± 0.08 mm, and 1.25 ± 0.58 mm, respectively; the VD, DSC, ASSD, RMSSSD, and MSSD for the canine were 49.12 ± 9.33 mm{sup 3}, 91.57 ± 0.82%, 0.27 ± 0.02 mm, 0

  3. Toward accurate tooth segmentation from computed tomography images using a hybrid level set model

    International Nuclear Information System (INIS)

    Gan, Yangzhou; Zhao, Qunfei; Xia, Zeyang; Hu, Ying; Xiong, Jing; Zhang, Jianwei

    2015-01-01

    Purpose: A three-dimensional (3D) model of the teeth provides important information for orthodontic diagnosis and treatment planning. Tooth segmentation is an essential step in generating the 3D digital model from computed tomography (CT) images. The aim of this study is to develop an accurate and efficient tooth segmentation method from CT images. Methods: The 3D dental CT volumetric images are segmented slice by slice in a two-dimensional (2D) transverse plane. The 2D segmentation is composed of a manual initialization step and an automatic slice by slice segmentation step. In the manual initialization step, the user manually picks a starting slice and selects a seed point for each tooth in this slice. In the automatic slice segmentation step, a developed hybrid level set model is applied to segment tooth contours from each slice. Tooth contour propagation strategy is employed to initialize the level set function automatically. Cone beam CT (CBCT) images of two subjects were used to tune the parameters. Images of 16 additional subjects were used to validate the performance of the method. Volume overlap metrics and surface distance metrics were adopted to assess the segmentation accuracy quantitatively. The volume overlap metrics were volume difference (VD, mm 3 ) and Dice similarity coefficient (DSC, %). The surface distance metrics were average symmetric surface distance (ASSD, mm), RMS (root mean square) symmetric surface distance (RMSSSD, mm), and maximum symmetric surface distance (MSSD, mm). Computation time was recorded to assess the efficiency. The performance of the proposed method has been compared with two state-of-the-art methods. Results: For the tested CBCT images, the VD, DSC, ASSD, RMSSSD, and MSSD for the incisor were 38.16 ± 12.94 mm 3 , 88.82 ± 2.14%, 0.29 ± 0.03 mm, 0.32 ± 0.08 mm, and 1.25 ± 0.58 mm, respectively; the VD, DSC, ASSD, RMSSSD, and MSSD for the canine were 49.12 ± 9.33 mm 3 , 91.57 ± 0.82%, 0.27 ± 0.02 mm, 0.28 ± 0.03 mm

  4. Browse Title Index

    African Journals Online (AJOL)

    Issue, Title. Vol 17 (2005), A. C. conduction behaviour in amorphous WO3/CEO2 thin film, Abstract. B Yagoubi, C A Hogarth, A Boukorrt. Vol 16 (2003), A lossless image compression algorithm using variable block size segmentation, Abstract. Z Brahimi, K A Saadi, N Baraka. Vol 15 (2003), Analysis method of wavelet ...

  5. Browse Title Index

    African Journals Online (AJOL)

    Vol 87, No 3 (2010), Optimisation of patient protection and image quality in ... Vol 81, No 1 (2004):, Oral habits among 7-10 year-old school children in Ibadan, Nigeria ... attitudes and practices of parents/guardians of pre-school children in Moshi, ... Vol 84, No 11 (2007), Osteoperosis - from hormonal replacement therapy to ...

  6. Combining low level features and visual attributes for VHR remote sensing image classification

    Science.gov (United States)

    Zhao, Fumin; Sun, Hao; Liu, Shuai; Zhou, Shilin

    2015-12-01

    Semantic classification of very high resolution (VHR) remote sensing images is of great importance for land use or land cover investigation. A large number of approaches exploiting different kinds of low level feature have been proposed in the literature. Engineers are often frustrated by their conclusions and a systematic assessment of various low level features for VHR remote sensing image classification is needed. In this work, we firstly perform an extensive evaluation of eight features including HOG, dense SIFT, SSIM, GIST, Geo color, LBP, Texton and Tiny images for classification of three public available datasets. Secondly, we propose to transfer ground level scene attributes to remote sensing images. Thirdly, we combine both low-level features and mid-level visual attributes to further improve the classification performance. Experimental results demonstrate that i) Dene SIFT and HOG features are more robust than other features for VHR scene image description. ii) Visual attribute competes with a combination of low level features. iii) Multiple feature combination achieves the best performance under different settings.

  7. SYNTACTIC COMPLEXITY IN THE READING MATERIALS OF ENGLISH FOR ACADEMIC PURPOSES LEVELS 1 – 3

    Directory of Open Access Journals (Sweden)

    Widdy Wijanti

    2017-10-01

    Full Text Available LLT Journal: A Journal on Language and Language Teaching Open Journal Systems LLT Journal ISSNs: e-ISSN: 2579-9533 (electronic p-ISSN: 1410-7201 (print User Username Password Remember me Journal Content Search Search Scope Browse By Issue By Author By Title Other Journals Font Size Make font size smaller Make font size default Make font size larger LLT Journal Barcode TOOLS FULL PAPER GUIDELINES Article Tools Print this article Indexing metadata How to cite item Email this article (Login required Email the author (Login required About The Author Widdy Wijanti Sampoerna University, Jakarta Indonesia OUR CONTACT LLT Journal English Language Education Sanata Dharma University Yogyakarta, Indonesia For more details, please visit: LLT Journal Contact Address Home About Login Register Search Current Archives Author Guidelines Editorial Team Focus and Scope Publication Ethics Author Index Originality Screening Indexing and Abstracting Review Process Article Processing Charges Article Submission Charges Publishing Rights Peer Reviewers Home > Vol 20, No 2 (2017 > Wijanti SYNTACTIC COMPLEXITY IN THE READING MATERIALS OF ENGLISH FOR ACADEMIC PURPOSES LEVELS 1 – 3 Widdy Wijanti Abstract In Indonesia, English is still considered as a foreign language and has become a crucial subject of study especially in the university level. For this reason, English for Academic Purposes has been conducted in the first year of college level for many years. Unfortunately, although many Asian countries including Indonesia have run the EAP course, the output is that there are still many Indonesian students who do not meet the vocabulary size and syntactic complexity that are expected while their learning process in the university. This results lower grades that they have in their assignments. Therefore, the recent study is aimed at evaluating the reading materials of EAP, especially in measuring the syntactic complexity containing in the texts as it is strongly believed in

  8. Intensity-based segmentation and visualization of cells in 3D microscopic images using the GPU

    Science.gov (United States)

    Kang, Mi-Sun; Lee, Jeong-Eom; Jeon, Woong-ki; Choi, Heung-Kook; Kim, Myoung-Hee

    2013-02-01

    3D microscopy images contain abundant astronomical data, rendering 3D microscopy image processing time-consuming and laborious on a central processing unit (CPU). To solve these problems, many people crop a region of interest (ROI) of the input image to a small size. Although this reduces cost and time, there are drawbacks at the image processing level, e.g., the selected ROI strongly depends on the user and there is a loss in original image information. To mitigate these problems, we developed a 3D microscopy image processing tool on a graphics processing unit (GPU). Our tool provides efficient and various automatic thresholding methods to achieve intensity-based segmentation of 3D microscopy images. Users can select the algorithm to be applied. Further, the image processing tool provides visualization of segmented volume data and can set the scale, transportation, etc. using a keyboard and mouse. However, the 3D objects visualized fast still need to be analyzed to obtain information for biologists. To analyze 3D microscopic images, we need quantitative data of the images. Therefore, we label the segmented 3D objects within all 3D microscopic images and obtain quantitative information on each labeled object. This information can use the classification feature. A user can select the object to be analyzed. Our tool allows the selected object to be displayed on a new window, and hence, more details of the object can be observed. Finally, we validate the effectiveness of our tool by comparing the CPU and GPU processing times by matching the specification and configuration.

  9. Metrological characterization of 3D imaging devices

    Science.gov (United States)

    Guidi, G.

    2013-04-01

    Manufacturers often express the performance of a 3D imaging device in various non-uniform ways for the lack of internationally recognized standard requirements for metrological parameters able to identify the capability of capturing a real scene. For this reason several national and international organizations in the last ten years have been developing protocols for verifying such performance. Ranging from VDI/VDE 2634, published by the Association of German Engineers and oriented to the world of mechanical 3D measurements (triangulation-based devices), to the ASTM technical committee E57, working also on laser systems based on direct range detection (TOF, Phase Shift, FM-CW, flash LADAR), this paper shows the state of the art about the characterization of active range devices, with special emphasis on measurement uncertainty, accuracy and resolution. Most of these protocols are based on special objects whose shape and size are certified with a known level of accuracy. By capturing the 3D shape of such objects with a range device, a comparison between the measured points and the theoretical shape they should represent is possible. The actual deviations can be directly analyzed or some derived parameters can be obtained (e.g. angles between planes, distances between barycenters of spheres rigidly connected, frequency domain parameters, etc.). This paper shows theoretical aspects and experimental results of some novel characterization methods applied to different categories of active 3D imaging devices based on both principles of triangulation and direct range detection.

  10. Combining semantic technologies with a content-based image retrieval system - Preliminary considerations

    Science.gov (United States)

    Chmiel, P.; Ganzha, M.; Jaworska, T.; Paprzycki, M.

    2017-10-01

    Nowadays, as a part of systematic growth of volume, and variety, of information that can be found on the Internet, we observe also dramatic increase in sizes of available image collections. There are many ways to help users browsing / selecting images of interest. One of popular approaches are Content-Based Image Retrieval (CBIR) systems, which allow users to search for images that match their interests, expressed in the form of images (query by example). However, we believe that image search and retrieval could take advantage of semantic technologies. We have decided to test this hypothesis. Specifically, on the basis of knowledge captured in the CBIR, we have developed a domain ontology of residential real estate (detached houses, in particular). This allows us to semantically represent each image (and its constitutive architectural elements) represented within the CBIR. The proposed ontology was extended to capture not only the elements resulting from image segmentation, but also "spatial relations" between them. As a result, a new approach to querying the image database (semantic querying) has materialized, thus extending capabilities of the developed system.

  11. Recent progress in low-level gamma imaging

    International Nuclear Information System (INIS)

    Mahe, C.; Girones, Ph.; Lamadie, F.; Le Goaller, C.

    2007-01-01

    The CEA's Aladin gamma imaging system has been operated successfully for several years in nuclear plants and during decommissioning projects with additional tools such as gamma spectrometry detectors and dose rate probes. The radiological information supplied by these devices is becoming increasingly useful for establishing robust and optimized decommissioning scenarios. Recent technical improvements allow this gamma imaging system to be operated in low-level applications and with shorter acquisition times suitable for decommissioning projects. The compact portable system can be used in places inaccessible to operators. It is quick and easy to implement, notably for onsite component characterization. Feasibility trials and in situ measurements were recently carried out under low-level conditions, mainly on waste packages and glove boxes for decommissioning projects. This paper describes recent low-level in situ applications. These characterization campaigns mainly concerned gamma emitters with γ energy < 700 keV. In many cases, the localization of hot spots by gamma camera was confirmed by additional measurements such as dose rate mapping and gamma spectrometry measurements. These complementary techniques associated with advanced calculation codes (MCNP, Mercure 6.2, Visiplan and Siren) offer a mobile and compact tool for specific assessment of waste packages and glove boxes. (authors)

  12. Software for 3D diagnostic image reconstruction and analysis

    International Nuclear Information System (INIS)

    Taton, G.; Rokita, E.; Sierzega, M.; Klek, S.; Kulig, J.; Urbanik, A.

    2005-01-01

    Recent advances in computer technologies have opened new frontiers in medical diagnostics. Interesting possibilities are the use of three-dimensional (3D) imaging and the combination of images from different modalities. Software prepared in our laboratories devoted to 3D image reconstruction and analysis from computed tomography and ultrasonography is presented. In developing our software it was assumed that it should be applicable in standard medical practice, i.e. it should work effectively with a PC. An additional feature is the possibility of combining 3D images from different modalities. The reconstruction and data processing can be conducted using a standard PC, so low investment costs result in the introduction of advanced and useful diagnostic possibilities. The program was tested on a PC using DICOM data from computed tomography and TIFF files obtained from a 3D ultrasound system. The results of the anthropomorphic phantom and patient data were taken into consideration. A new approach was used to achieve spatial correlation of two independently obtained 3D images. The method relies on the use of four pairs of markers within the regions under consideration. The user selects the markers manually and the computer calculates the transformations necessary for coupling the images. The main software feature is the possibility of 3D image reconstruction from a series of two-dimensional (2D) images. The reconstructed 3D image can be: (1) viewed with the most popular methods of 3D image viewing, (2) filtered and processed to improve image quality, (3) analyzed quantitatively (geometrical measurements), and (4) coupled with another, independently acquired 3D image. The reconstructed and processed 3D image can be stored at every stage of image processing. The overall software performance was good considering the relatively low costs of the hardware used and the huge data sets processed. The program can be freely used and tested (source code and program available at

  13. A novel image encryption algorithm based on a 3D chaotic map

    Science.gov (United States)

    Kanso, A.; Ghebleh, M.

    2012-07-01

    Recently [Solak E, Çokal C, Yildiz OT Biyikoǧlu T. Cryptanalysis of Fridrich's chaotic image encryption. Int J Bifur Chaos 2010;20:1405-1413] cryptanalyzed the chaotic image encryption algorithm of [Fridrich J. Symmetric ciphers based on two-dimensional chaotic maps. Int J Bifur Chaos 1998;8(6):1259-1284], which was considered a benchmark for measuring security of many image encryption algorithms. This attack can also be applied to other encryption algorithms that have a structure similar to Fridrich's algorithm, such as that of [Chen G, Mao Y, Chui, C. A symmetric image encryption scheme based on 3D chaotic cat maps. Chaos Soliton Fract 2004;21:749-761]. In this paper, we suggest a novel image encryption algorithm based on a three dimensional (3D) chaotic map that can defeat the aforementioned attack among other existing attacks. The design of the proposed algorithm is simple and efficient, and based on three phases which provide the necessary properties for a secure image encryption algorithm including the confusion and diffusion properties. In phase I, the image pixels are shuffled according to a search rule based on the 3D chaotic map. In phases II and III, 3D chaotic maps are used to scramble shuffled pixels through mixing and masking rules, respectively. Simulation results show that the suggested algorithm satisfies the required performance tests such as high level security, large key space and acceptable encryption speed. These characteristics make it a suitable candidate for use in cryptographic applications.

  14. Parallax barrier engineering for image quality improvement in an autostereoscopic 3D display.

    Science.gov (United States)

    Kim, Sung-Kyu; Yoon, Ki-Hyuk; Yoon, Seon Kyu; Ju, Heongkyu

    2015-05-18

    We present a image quality improvement in a parallax barrier (PB)-based multiview autostereoscopic 3D display system under a real-time tracking of positions of a viewer's eyes. The system presented exploits a parallax barrier engineered to offer significantly improved quality of three-dimensional images for a moving viewer without an eyewear under the dynamic eye tracking. The improved image quality includes enhanced uniformity of image brightness, reduced point crosstalk, and no pseudoscopic effects. We control the relative ratio between two parameters i.e., a pixel size and the aperture of a parallax barrier slit to improve uniformity of image brightness at a viewing zone. The eye tracking that monitors positions of a viewer's eyes enables pixel data control software to turn on only pixels for view images near the viewer's eyes (the other pixels turned off), thus reducing point crosstalk. The eye tracking combined software provides right images for the respective eyes, therefore producing no pseudoscopic effects at its zone boundaries. The viewing zone can be spanned over area larger than the central viewing zone offered by a conventional PB-based multiview autostereoscopic 3D display (no eye tracking). Our 3D display system also provides multiviews for motion parallax under eye tracking. More importantly, we demonstrate substantial reduction of point crosstalk of images at the viewing zone, its level being comparable to that of a commercialized eyewear-assisted 3D display system. The multiview autostereoscopic 3D display presented can greatly resolve the point crosstalk problem, which is one of the critical factors that make it difficult for previous technologies for a multiview autostereoscopic 3D display to replace an eyewear-assisted counterpart.

  15. Imaging system for creating 3D block-face cryo-images of whole mice

    Science.gov (United States)

    Roy, Debashish; Breen, Michael; Salvado, Olivier; Heinzel, Meredith; McKinley, Eliot; Wilson, David

    2006-03-01

    We developed a cryomicrotome/imaging system that provides high resolution, high sensitivity block-face images of whole mice or excised organs, and applied it to a variety of biological applications. With this cryo-imaging system, we sectioned cryo-preserved tissues at 2-40 μm thickness and acquired high resolution brightfield and fluorescence images with microscopic in-plane resolution (as good as 1.2 μm). Brightfield images of normal and pathological anatomy show exquisite detail, especially in the abdominal cavity. Multi-planar reformatting and 3D renderings allow one to interrogate 3D structures. In this report, we present brightfield images of mouse anatomy, as well as 3D renderings of organs. For BPK mice model of polycystic kidney disease, we compared brightfield cryo-images and kidney volumes to MRI. The color images provided greater contrast and resolution of cysts as compared to in vivo MRI. We note that color cryo-images are closer to what a researcher sees in dissection, making it easier for them to interpret image data. The combination of field of view, depth of field, ultra high resolution and color/fluorescence contrast enables cryo-image volumes to provide details that cannot be found through in vivo imaging or other ex vivo optical imaging approaches. We believe that this novel imaging system will have applications that include identification of mouse phenotypes, characterization of diseases like blood vessel disease, kidney disease, and cancer, assessment of drug and gene therapy delivery and efficacy and validation of other imaging modalities.

  16. A secure online image trading system for untrusted cloud environments.

    Science.gov (United States)

    Munadi, Khairul; Arnia, Fitri; Syaryadhi, Mohd; Fujiyoshi, Masaaki; Kiya, Hitoshi

    2015-01-01

    In conventional image trading systems, images are usually stored unprotected on a server, rendering them vulnerable to untrusted server providers and malicious intruders. This paper proposes a conceptual image trading framework that enables secure storage and retrieval over Internet services. The process involves three parties: an image publisher, a server provider, and an image buyer. The aim is to facilitate secure storage and retrieval of original images for commercial transactions, while preventing untrusted server providers and unauthorized users from gaining access to true contents. The framework exploits the Discrete Cosine Transform (DCT) coefficients and the moment invariants of images. Original images are visually protected in the DCT domain, and stored on a repository server. Small representation of the original images, called thumbnails, are generated and made publicly accessible for browsing. When a buyer is interested in a thumbnail, he/she sends a query to retrieve the visually protected image. The thumbnails and protected images are matched using the DC component of the DCT coefficients and the moment invariant feature. After the matching process, the server returns the corresponding protected image to the buyer. However, the image remains visually protected unless a key is granted. Our target application is the online market, where publishers sell their stock images over the Internet using public cloud servers.

  17. 3D Reconstruction of NMR Images

    Directory of Open Access Journals (Sweden)

    Peter Izak

    2007-01-01

    Full Text Available This paper introduces experiment of 3D reconstruction NMR images scanned from magnetic resonance device. There are described methods which can be used for 3D reconstruction magnetic resonance images in biomedical application. The main idea is based on marching cubes algorithm. For this task was chosen sophistication method by program Vision Assistant, which is a part of program LabVIEW.

  18. Knowledge-based low-level image analysis for computer vision systems

    Science.gov (United States)

    Dhawan, Atam P.; Baxi, Himanshu; Ranganath, M. V.

    1988-01-01

    Two algorithms for entry-level image analysis and preliminary segmentation are proposed which are flexible enough to incorporate local properties of the image. The first algorithm involves pyramid-based multiresolution processing and a strategy to define and use interlevel and intralevel link strengths. The second algorithm, which is designed for selected window processing, extracts regions adaptively using local histograms. The preliminary segmentation and a set of features are employed as the input to an efficient rule-based low-level analysis system, resulting in suboptimal meaningful segmentation.

  19. Mining dark information resources to develop new informatics capabilities to support science

    Science.gov (United States)

    Ramachandran, Rahul; Maskey, Manil; Bugbee, Kaylin

    2016-04-01

    Dark information resources are digital resources that organizations collect, process, and store for regular business or operational activities but fail to realize their potential for other purposes. The challenge for any organization is to recognize, identify and effectively exploit these dark information stores. Metadata catalogs at different data centers store dark information resources consisting of structured information, free form descriptions of data and browse images. These information resources are never fully exploited beyond a few fields used for search and discovery. For example, the NASA Earth science catalog holds greater than 6000 data collections, 127 million records for individual files and 67 million browse images. We believe that the information contained in the metadata catalogs and the browse images can be utilized beyond their original design intent to provide new data discovery and exploration pathways to support science and education communities. In this paper we present two research applications using information stored in the metadata catalog in a completely novel way. The first application is designing a data curation service. The objective of the data curation service is to augment the existing data search capabilities. Given a specific atmospheric phenomenon, the data curation service returns the user a ranked list of relevant data sets. Different fields in the metadata records including textual descriptions are mined. A specialized relevancy ranking algorithm has been developed that uses a "bag of words" to define phenomena along with an ensemble of known approaches such as the Jaccard Coefficient, Cosine Similarity and Zone ranking to rank the data sets. This approach is also extended to map from the data set level to data file variable level. The second application is focused on providing a service where a user can search and discover browse images containing specific phenomena from the vast catalog. This service will aid researchers

  20. Minimally invasive vascular imaging using 3D-CTA and 3D-MRA. Update

    International Nuclear Information System (INIS)

    Hayashi, Hiromitsu; Kawamata, Hiroshi; Takagi, Ryo; Amano, Yasuo; Wakabayashi, Hiroyuki; Ichikawa, Kazuo; Kumazaki, Tatsuo

    1998-01-01

    Conventional angiography is considered the standard of reference for diagnostic imaging of vascular diseases with respect to its temporal and spatial resolution. This procedure, however is invasive and repeated studies are difficult, and arterial complications are occasionally associated in catheter-based conventional angiography. Recent advances in diagnostic imaging have facilitated three-dimensional CT angiography (3D-CTA) using the volumetric acquisition capabilities inherent in spiral CT and three-dimensional MR angiography (3D-MRA) using the 3D gradient-echo sequence with a bolus injection of Gd-DTPA. These techniques can provide vascular images exceedingly similar to conventional angiograms within a short acquisition time. 3D-CTA and 3D-MRA are considered to be promising, minimally invasive methods for obtaining images of the vasculature, and alternatives to catheter angiography. This study reviews the current status of 3D-CTA and 3D-MRA, with emphasis on the clinical usefulness of three-dimensional diagnostic imaging for the evaluation of diverse vascular pathologies. (author)

  1. 3D widefield light microscope image reconstruction without dyes

    Science.gov (United States)

    Larkin, S.; Larson, J.; Holmes, C.; Vaicik, M.; Turturro, M.; Jurkevich, A.; Sinha, S.; Ezashi, T.; Papavasiliou, G.; Brey, E.; Holmes, T.

    2015-03-01

    3D image reconstruction using light microscope modalities without exogenous contrast agents is proposed and investigated as an approach to produce 3D images of biological samples for live imaging applications. Multimodality and multispectral imaging, used in concert with this 3D optical sectioning approach is also proposed as a way to further produce contrast that could be specific to components in the sample. The methods avoid usage of contrast agents. Contrast agents, such as fluorescent or absorbing dyes, can be toxic to cells or alter cell behavior. Current modes of producing 3D image sets from a light microscope, such as 3D deconvolution algorithms and confocal microscopy generally require contrast agents. Zernike phase contrast (ZPC), transmitted light brightfield (TLB), darkfield microscopy and others can produce contrast without dyes. Some of these modalities have not previously benefitted from 3D image reconstruction algorithms, however. The 3D image reconstruction algorithm is based on an underlying physical model of scattering potential, expressed as the sample's 3D absorption and phase quantities. The algorithm is based upon optimizing an objective function - the I-divergence - while solving for the 3D absorption and phase quantities. Unlike typical deconvolution algorithms, each microscope modality, such as ZPC or TLB, produces two output image sets instead of one. Contrast in the displayed image and 3D renderings is further enabled by treating the multispectral/multimodal data as a feature set in a mathematical formulation that uses the principal component method of statistics.

  2. Modeling of video traffic in packet networks, low rate video compression, and the development of a lossy+lossless image compression algorithm

    Science.gov (United States)

    Sayood, K.; Chen, Y. C.; Wang, X.

    1992-01-01

    During this reporting period we have worked on three somewhat different problems. These are modeling of video traffic in packet networks, low rate video compression, and the development of a lossy + lossless image compression algorithm, which might have some application in browsing algorithms. The lossy + lossless scheme is an extension of work previously done under this grant. It provides a simple technique for incorporating browsing capability. The low rate coding scheme is also a simple variation on the standard discrete cosine transform (DCT) coding approach. In spite of its simplicity, the approach provides surprisingly high quality reconstructions. The modeling approach is borrowed from the speech recognition literature, and seems to be promising in that it provides a simple way of obtaining an idea about the second order behavior of a particular coding scheme. Details about these are presented.

  3. Preliminary examples of 3D vector flow imaging

    DEFF Research Database (Denmark)

    Pihl, Michael Johannes; Stuart, Matthias Bo; Tomov, Borislav Gueorguiev

    2013-01-01

    This paper presents 3D vector flow images obtained using the 3D Transverse Oscillation (TO) method. The method employs a 2D transducer and estimates the three velocity components simultaneously, which is important for visualizing complex flow patterns. Data are acquired using the experimental ult...... as opposed to magnetic resonance imaging (MRI). The results demonstrate that the 3D TO method is capable of performing 3D vector flow imaging.......This paper presents 3D vector flow images obtained using the 3D Transverse Oscillation (TO) method. The method employs a 2D transducer and estimates the three velocity components simultaneously, which is important for visualizing complex flow patterns. Data are acquired using the experimental...... ultrasound scanner SARUS on a flow rig system with steady flow. The vessel of the flow-rig is centered at a depth of 30 mm, and the flow has an expected 2D circular-symmetric parabolic prole with a peak velocity of 1 m/s. Ten frames of 3D vector flow images are acquired in a cross-sectional plane orthogonal...

  4. IT infrastructure in the era of imaging 3.0.

    Science.gov (United States)

    McGinty, Geraldine B; Allen, Bibb; Geis, J Raymond; Wald, Christoph

    2014-12-01

    Imaging 3.0 is a blueprint for the future of radiology modeled after the description of Web 3.0 as "more connected, more open, and more intelligent." Imaging 3.0 involves radiologists' using their expertise to manage all aspects of imaging care to improve patient safety and outcomes and to deliver high-value care. IT tools are critical elements and drivers of success as radiologists embrace the concepts of Imaging 3.0. Organized radiology, specifically the ACR, is the natural convener and resource for the development of this Imaging 3.0 toolkit. The ACR's new Imaging 3.0 Informatics Committee is actively working to develop the informatics tools radiologists need to improve efficiency, deliver more value, and provide quantitative ways to demonstrate their value in new health care delivery and payment systems. This article takes each step of the process of delivering high-value Imaging 3.0 care and outlines the tools available as well as additional resources available to support practicing radiologists. From the moment when imaging is considered through the delivery of a meaningful and actionable report that is communicated to the referring clinician and, when appropriate, to the patient, Imaging 3.0 IT tools will enable radiologists to position themselves as vital constituents in cost-effective, high-value health care. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  5. Spatial correlations between browsing on balsam fir by white-tailed deer and the nutritional value of neighboring winter forage.

    Science.gov (United States)

    Champagne, Emilie; Moore, Ben D; Côté, Steeve D; Tremblay, Jean-Pierre

    2018-03-01

    Associational effects, that is, the influence of neighboring plants on herbivory suffered by a plant, are an outcome of forage selection. Although forage selection is a hierarchical process, few studies have investigated associational effects at multiple spatial scales. Because the nutritional quality of plants can be spatially structured, it might differently influence associational effects across multiple scales. Our objective was to determine the radius of influence of neighbor density and nutritional quality on balsam fir ( Abies balsamea ) herbivory by white-tailed deer ( Odocoileus virginianus ) in winter. We quantified browsing rates on fir and the density and quality of neighboring trees in a series of 10-year-old cutovers on Anticosti Island (Canada). We used cross-correlations to investigate relationships between browsing rates and the density and nutritional quality of neighboring trees at distances up to 1,000 m. Balsam fir and white spruce ( Picea glauca ) fiber content and dry matter in vitro true digestibility were correlated with fir browsing rate at the finest extra-patch scale (across distance of up to 50 m) and between cutover areas (300-400 m). These correlations suggest associational effects, that is, low nutritional quality of neighbors reduces the likelihood of fir herbivory (associational defense). Our results may indicate associational effects mediated by intraspecific variation in plant quality and suggest that these effects could occur at scales from tens to hundreds of meters. Understanding associational effects could inform strategies for restoration or conservation; for example, planting of fir among existing natural regeneration could be concentrated in areas of low nutritional quality.

  6. Lossless, Near-Lossless, and Refinement Coding of Bi-level Images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren Otto

    1999-01-01

    We present general and unified algorithms for lossy/lossless coding of bi-level images. The compression is realized by applying arithmetic coding to conditional probabilities. As in the current JBIG standard the conditioning may be specified by a template.For better compression, the more general...... to the specialized soft pattern matching techniques which work better for text. Template based refinement coding is applied for lossy-to-lossless refinement. Introducing only a small amount of loss in halftoned test images, compression is increased by up to a factor of four compared with JBIG. Lossy, lossless......, and refinement decoding speed and lossless encoding speed are less than a factor of two slower than JBIG. The (de)coding method is proposed as part of JBIG2, an emerging international standard for lossless/lossy compression of bi-level images....

  7. Social comparisons on social media: The impact of Facebook on young women’s body image concerns and mood

    OpenAIRE

    Fardouly, J.; Diedrichs, P. C.; Vartanian, L.; Halliwell, E.

    2015-01-01

    The present study experimentally investigated the effect of Facebook usage on women’s mood and body image, whether these effects differ from an online fashion magazine, and whether appearance comparison tendency moderates any of these effects. Female participants (n = 112) were randomly assigned to spend 10 minutes browsing their Facebook account, a magazine website, or an appearance-neutral control website before completing state measures of mood, body dissatisfaction, and appearance discrep...

  8. Contributions in compression of 3D medical images and 2D images; Contributions en compression d'images medicales 3D et d'images naturelles 2D

    Energy Technology Data Exchange (ETDEWEB)

    Gaudeau, Y

    2006-12-15

    The huge amounts of volumetric data generated by current medical imaging techniques in the context of an increasing demand for long term archiving solutions, as well as the rapid development of distant radiology make the use of compression inevitable. Indeed, if the medical community has sided until now with compression without losses, most of applications suffer from compression ratios which are too low with this kind of compression. In this context, compression with acceptable losses could be the most appropriate answer. So, we propose a new loss coding scheme based on 3D (3 dimensional) Wavelet Transform and Dead Zone Lattice Vector Quantization 3D (DZLVQ) for medical images. Our algorithm has been evaluated on several computerized tomography (CT) and magnetic resonance image volumes. The main contribution of this work is the design of a multidimensional dead zone which enables to take into account correlations between neighbouring elementary volumes. At high compression ratios, we show that it can out-perform visually and numerically the best existing methods. These promising results are confirmed on head CT by two medical patricians. The second contribution of this document assesses the effect with-loss image compression on CAD (Computer-Aided Decision) detection performance of solid lung nodules. This work on 120 significant lungs images shows that detection did not suffer until 48:1 compression and still was robust at 96:1. The last contribution consists in the complexity reduction of our compression scheme. The first allocation dedicated to 2D DZLVQ uses an exponential of the rate-distortion (R-D) functions. The second allocation for 2D and 3D medical images is based on block statistical model to estimate the R-D curves. These R-D models are based on the joint distribution of wavelet vectors using a multidimensional mixture of generalized Gaussian (MMGG) densities. (author)

  9. Construction of static 3D ultrasonography image by radiation beam tracking method from 1D array probe

    Energy Technology Data Exchange (ETDEWEB)

    Doh, Il; Kim, Yong Tae; Ahn, Bong Young [Center for Medical Metrology, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Kim, Kwang Youn [Meta biomed Co.,Ltd, Cheongju (Korea, Republic of)

    2015-04-15

    This paper describes the construction of a static 3D ultrasonography image by tracking the radiation beam position during the handy operation of a 1D array probe to enable point-of-care use. The theoretical model of the transformation from the translational and rotational information of the sensor mounted on the probe to the reference Cartesian coordinate system was given. The signal amplification and serial communication interface module was made using a commercially available sensor. A test phantom was also made using silicone putty in a donut shape. During the movement of the hand-held probe, B-mode movie and sensor signals were recorded. B-mode images were periodically selected from the movie, and the gray levels of the pixels for each image were converted to the gray levels of 3D voxels. 3D and 2D images of arbitrary cross-section of the B-mode type were also constructed from the voxel data, and agreed well with the shape of the test phantom.

  10. Store Image: Scale implementation Part 3

    Directory of Open Access Journals (Sweden)

    Ronel du Preez

    2008-10-01

    Full Text Available This paper is the final in the three-part series regarding store image. The purposes of this article are to (1 implement the developed scale to assess whether it illustrates acceptable psychometric properties of reliability and validity, (2 assess the model fit of the developed scale and (3 formulate recommendations for future research. Results indicated that the Apparel Store Image Scale (ASIS show acceptable reliability and model fit. A refined definition of store image was proposed together with a Final Model of Apparel Store Image. Recommendations for future research are made.

  11. Context-Aware Browsing for Hyper-Local News Data (CABHLND

    Directory of Open Access Journals (Sweden)

    Dr. Yousef Ibrahim Daradkeh

    2012-07-01

    Full Text Available This paper describes a new model for delivering hyper-local data to mobile subscribers. Our model uses any exiting or especially created Wi-Fi hot spot as presence sensor that can open access for some user-generated content. In our approach we can describe hyper local data as info snippets that are valid (relevant for mobile subscribers being at this moment nearby some Wi-Fi access point. And an appropriate mobile service (customized browser can discover that information to mobile users. Service builds on the fly dynamic web pages and lets mobile subscribers to browse hyper-local data only. As the possible use-cases we can mention for example delivering news and deals in malls, news feeds for office centers and campuses, Smart City projects, personal classifieds etc.

  12. A deep level set method for image segmentation

    OpenAIRE

    Tang, Min; Valipour, Sepehr; Zhang, Zichen Vincent; Cobzas, Dana; MartinJagersand

    2017-01-01

    This paper proposes a novel image segmentation approachthat integrates fully convolutional networks (FCNs) with a level setmodel. Compared with a FCN, the integrated method can incorporatesmoothing and prior information to achieve an accurate segmentation.Furthermore, different than using the level set model as a post-processingtool, we integrate it into the training phase to fine-tune the FCN. Thisallows the use of unlabeled data during training in a semi-supervisedsetting. Using two types o...

  13. Effect of glucose level on brain FDG-PET images

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Young; Lee, Yong Ki; Ahn, Sung Min [Dept. of Radiological Science, Gachon University, Seongnam (Korea, Republic of)

    2017-06-15

    In addition to tumors, normal tissues, such as the brain and myocardium can intake {sup 18}F-FDG, and the amount of {sup 18}F-FDG intake by normal tissues can be altered by the surrounding environment. Therefore, a process is necessary during which the contrasts of the tumor and normal tissues can be enhanced. Thus, this study examines the effects of glucose levels on FDG PET images of brain tissues, which features high glucose activity at all times, in small animals. Micro PET scan was performed on fourteen mice after injecting {sup 18}F-FDG. The images were compared in relation to fasting. The findings showed that the mean SUV value w as 0 .84 higher in fasted mice than in non-fasted mice. During observation, the images from non-fasted mice showed high accumulation in organs other than the brain with increased surrounding noise. In addition, compared to the non-fasted mice, the fasted mice showed higher early intake and curve increase. The findings of this study suggest that fasting is important in assessing brain functions in brain PET using {sup 18}F-FDG. Additional studies to investigate whether caffeine levels and other preprocessing items have an impact on the acquired images would contribute to reducing radiation exposure in patients.

  14. Effect of glucose level on brain FDG-PET images

    International Nuclear Information System (INIS)

    Kim, In Young; Lee, Yong Ki; Ahn, Sung Min

    2017-01-01

    In addition to tumors, normal tissues, such as the brain and myocardium can intake 18 F-FDG, and the amount of 18 F-FDG intake by normal tissues can be altered by the surrounding environment. Therefore, a process is necessary during which the contrasts of the tumor and normal tissues can be enhanced. Thus, this study examines the effects of glucose levels on FDG PET images of brain tissues, which features high glucose activity at all times, in small animals. Micro PET scan was performed on fourteen mice after injecting 18 F-FDG. The images were compared in relation to fasting. The findings showed that the mean SUV value w as 0 .84 higher in fasted mice than in non-fasted mice. During observation, the images from non-fasted mice showed high accumulation in organs other than the brain with increased surrounding noise. In addition, compared to the non-fasted mice, the fasted mice showed higher early intake and curve increase. The findings of this study suggest that fasting is important in assessing brain functions in brain PET using 18 F-FDG. Additional studies to investigate whether caffeine levels and other preprocessing items have an impact on the acquired images would contribute to reducing radiation exposure in patients

  15. 3D reconstruction based on light field images

    Science.gov (United States)

    Zhu, Dong; Wu, Chunhong; Liu, Yunluo; Fu, Dongmei

    2018-04-01

    This paper proposed a method of reconstructing three-dimensional (3D) scene from two light field images capture by Lytro illium. The work was carried out by first extracting the sub-aperture images from light field images and using the scale-invariant feature transform (SIFT) for feature registration on the selected sub-aperture images. Structure from motion (SFM) algorithm is further used on the registration completed sub-aperture images to reconstruct the three-dimensional scene. 3D sparse point cloud was obtained in the end. The method shows that the 3D reconstruction can be implemented by only two light field camera captures, rather than at least a dozen times captures by traditional cameras. This can effectively solve the time-consuming, laborious issues for 3D reconstruction based on traditional digital cameras, to achieve a more rapid, convenient and accurate reconstruction.

  16. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis.

    Science.gov (United States)

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-04-25

    Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM) techniques can further prevent the occurrence of false positives with conventional MRI, distinguish which are clinically relevant from levels of cauda equina and/or nerve root lesions based on MRI, and determine and reduce the decompression levels of lumbar spinal stenosis than MRI + NE, while ensuring or improving surgical outcomes. We compared the data between patients who underwent MRI + (PM or DTI) and patients who underwent conventional MRI + NE to determine levels of decompression for the treatment of lumbar spinal stenosis. Outcome measures were assessed at 2 weeks, 3 months, 6 months, and 12 months postoperatively. One hundred fourteen patients (59 in the control group, 54 in the experimental group) underwent decompression. The levels of decompression determined by MRI + (PM or DTI) in the experimental group were significantly less than that determined by MRI + NE in the control group (p = 0.000). The surgical time, blood loss, and surgical transfusion were significantly less in the experimental group (p = 0.001, p = 0.011, p = 0.001, respectively). There were no differences in improvement of the visual analog scale back and leg pain (VAS-BP, VAS-LP) scores and Oswestry Disability Index (ODI) scores at 2 weeks, 3 months, 6 months, and 12 months after operation between the experimental and control groups. MRI + (PM or DTI) showed clear benefits in determining decompression levels of lumbar spinal stenosis than MRI + NE. In patients with lumbar spinal

  17. Z-Index Parameterization for Volumetric CT Image Reconstruction via 3-D Dictionary Learning.

    Science.gov (United States)

    Bai, Ti; Yan, Hao; Jia, Xun; Jiang, Steve; Wang, Ge; Mou, Xuanqin

    2017-12-01

    Despite the rapid developments of X-ray cone-beam CT (CBCT), image noise still remains a major issue for the low dose CBCT. To suppress the noise effectively while retain the structures well for low dose CBCT image, in this paper, a sparse constraint based on the 3-D dictionary is incorporated into a regularized iterative reconstruction framework, defining the 3-D dictionary learning (3-DDL) method. In addition, by analyzing the sparsity level curve associated with different regularization parameters, a new adaptive parameter selection strategy is proposed to facilitate our 3-DDL method. To justify the proposed method, we first analyze the distributions of the representation coefficients associated with the 3-D dictionary and the conventional 2-D dictionary to compare their efficiencies in representing volumetric images. Then, multiple real data experiments are conducted for performance validation. Based on these results, we found: 1) the 3-D dictionary-based sparse coefficients have three orders narrower Laplacian distribution compared with the 2-D dictionary, suggesting the higher representation efficiencies of the 3-D dictionary; 2) the sparsity level curve demonstrates a clear Z-shape, and hence referred to as Z-curve, in this paper; 3) the parameter associated with the maximum curvature point of the Z-curve suggests a nice parameter choice, which could be adaptively located with the proposed Z-index parameterization (ZIP) method; 4) the proposed 3-DDL algorithm equipped with the ZIP method could deliver reconstructions with the lowest root mean squared errors and the highest structural similarity index compared with the competing methods; 5) similar noise performance as the regular dose FDK reconstruction regarding the standard deviation metric could be achieved with the proposed method using (1/2)/(1/4)/(1/8) dose level projections. The contrast-noise ratio is improved by ~2.5/3.5 times with respect to two different cases under the (1/8) dose level compared

  18. 3D nonrigid medical image registration using a new information theoretic measure

    Science.gov (United States)

    Li, Bicao; Yang, Guanyu; Coatrieux, Jean Louis; Li, Baosheng; Shu, Huazhong

    2015-11-01

    This work presents a novel method for the nonrigid registration of medical images based on the Arimoto entropy, a generalization of the Shannon entropy. The proposed method employed the Jensen-Arimoto divergence measure as a similarity metric to measure the statistical dependence between medical images. Free-form deformations were adopted as the transformation model and the Parzen window estimation was applied to compute the probability distributions. A penalty term is incorporated into the objective function to smooth the nonrigid transformation. The goal of registration is to optimize an objective function consisting of a dissimilarity term and a penalty term, which would be minimal when two deformed images are perfectly aligned using the limited memory BFGS optimization method, and thus to get the optimal geometric transformation. To validate the performance of the proposed method, experiments on both simulated 3D brain MR images and real 3D thoracic CT data sets were designed and performed on the open source elastix package. For the simulated experiments, the registration errors of 3D brain MR images with various magnitudes of known deformations and different levels of noise were measured. For the real data tests, four data sets of 4D thoracic CT from four patients were selected to assess the registration performance of the method, including ten 3D CT images for each 4D CT data covering an entire respiration cycle. These results were compared with the normalized cross correlation and the mutual information methods and show a slight but true improvement in registration accuracy.

  19. 3D nonrigid medical image registration using a new information theoretic measure

    International Nuclear Information System (INIS)

    Li, Bicao; Yang, Guanyu; Coatrieux, Jean Louis; Li, Baosheng; Shu, Huazhong

    2015-01-01

    This work presents a novel method for the nonrigid registration of medical images based on the Arimoto entropy, a generalization of the Shannon entropy. The proposed method employed the Jensen–Arimoto divergence measure as a similarity metric to measure the statistical dependence between medical images. Free-form deformations were adopted as the transformation model and the Parzen window estimation was applied to compute the probability distributions. A penalty term is incorporated into the objective function to smooth the nonrigid transformation. The goal of registration is to optimize an objective function consisting of a dissimilarity term and a penalty term, which would be minimal when two deformed images are perfectly aligned using the limited memory BFGS optimization method, and thus to get the optimal geometric transformation. To validate the performance of the proposed method, experiments on both simulated 3D brain MR images and real 3D thoracic CT data sets were designed and performed on the open source elastix package. For the simulated experiments, the registration errors of 3D brain MR images with various magnitudes of known deformations and different levels of noise were measured. For the real data tests, four data sets of 4D thoracic CT from four patients were selected to assess the registration performance of the method, including ten 3D CT images for each 4D CT data covering an entire respiration cycle. These results were compared with the normalized cross correlation and the mutual information methods and show a slight but true improvement in registration accuracy. (paper)

  20. Outdoor Urban Propagation Experiment of a Handset MIMO Antenna with a Human Phantom located in a Browsing Stance

    DEFF Research Database (Denmark)

    Yamamoto, Atsushi; Hayashi, Toshiteru; Ogawa, Koichi

    2007-01-01

    Outdoor radio propagation experiments are presented at 2.4 GHz, using a handset MIMO antenna with two monopoles and two planar inverted-F antennas (PIFAs), adjacent to a human phantom in browsing stance. The propagation test was performed in an urban area of a city, which resulted in non lineof...

  1. 3D Adaptive Virtual Exhibit for the University of Denver Digital Collections

    Directory of Open Access Journals (Sweden)

    Shea-Tinn Yeh

    2015-07-01

    Full Text Available While the gaming industry has taken the world by storm with its three-dimensional (3D user interfaces, current digital collection exhibits presented by museums, historical societies, and libraries are still limited to a two-dimensional (2D interface display. Why can’t digital collections take advantage of this 3D interface advancement? The prototype discussed in this paper presents to the visitor a 3D virtual exhibit containing a set of digital objects from the University of Denver Libraries’ digital image collections, giving visitors an immersive experience when viewing the collections. In particular, the interface is adaptive to the visitor’s browsing behaviors and alters the selection and display of the objects throughout the exhibit to encourage serendipitous discovery. Social media features were also integrated to allow visitors to share items of interest and to create a sense of virtual community.

  2. Denoising imaging polarimetry by adapted BM3D method.

    Science.gov (United States)

    Tibbs, Alexander B; Daly, Ilse M; Roberts, Nicholas W; Bull, David R

    2018-04-01

    In addition to the visual information contained in intensity and color, imaging polarimetry allows visual information to be extracted from the polarization of light. However, a major challenge of imaging polarimetry is image degradation due to noise. This paper investigates the mitigation of noise through denoising algorithms and compares existing denoising algorithms with a new method, based on BM3D (Block Matching 3D). This algorithm, Polarization-BM3D (PBM3D), gives visual quality superior to the state of the art across all images and noise standard deviations tested. We show that denoising polarization images using PBM3D allows the degree of polarization to be more accurately calculated by comparing it with spectral polarimetry measurements.

  3. [EYECUBE as 3D multimedia imaging in macular diagnostics].

    Science.gov (United States)

    Hassenstein, Andrea; Scholz, F; Richard, G

    2011-11-01

    In the new generation of EYECUBE devices, the angiography image and the OCT are included in a 3D illustration as an integration. Other diagnostic procedures such as autofluorescence and ICG can also be correlated to the OCT. The aim was to precisely classify various two-dimensional findings in relation to each other. The new generation of OCT devices enables imaging with a low incidence of motion artefacts with very good fundus image quality - and with that, permits a largely automatic classification. The feature enabling the integration of the EYECUBE was further developed with new software, so that not only the topographic image (red-free, autofluorescence) can be correlated to the Cirrus OCT, but also all other findings gathered within the same time frame can be correlated to each other. These were brightened and projected onto the cube surface in a defined interval. The imaging procedures can be selected in a menu toolbar. Topographic volumetry OCT images can be overlayed. The practical application of the new method was tested on patients with macular disorders. By lightening up the results from various diagnostic procedures, it is possible of late to directly compare pathologies to each other and to the OCT results. In all patients (n = 45 eyes) with good single-image quality, the automated integration into the EYECUBE was possible (to a great extent). The application is not dependent on a certain type of device used in the procedures performed. The increasing level of precision in imaging procedures and the handling of large data volumes has led to the possibility of examining each macular diagnostics procedure from the comparative perspective: imaging (photo) with perfusion (FLA, ICG) and morphology (OCT). The exclusion of motion artefacts and the reliable scan position in the course of the imaging process increases the informative value of OCT. © Georg Thieme Verlag KG Stuttgart · New York.

  4. The Establishment of the SAR images database System Based on Oracle and ArcSDE

    International Nuclear Information System (INIS)

    Zhou, Jijin; Li, Zhen; Chen, Quan; Tian, Bangsen

    2014-01-01

    Synthetic aperture radar is a kind of microwave imaging system, and has the advantages of multi-band, multi-polarization and multi-angle. At present, there is no SAR images database system based on typical features. For solving problems in interpretation and identification, a new SAR images database system of the typical features is urgent in the current development need. In this article, a SAR images database system based on Oracle and ArcSDE was constructed. The main works involving are as follows: (1) SAR image data was calibrated and corrected geometrically and geometrically. Besides, the fully polarimetric image was processed as the coherency matrix[T] to preserve the polarimetric information. (2) After analyzing multiple space borne SAR images, the metadata table was defined as: IMAGEID; Name of features; Latitude and Longitude; Sensor name; Range and Azimuth resolution etc. (3) Through the comparison between GeoRaster and ArcSDE, result showed ArcSDE is a more appropriate technology to store images in a central database. The System stores and manages multisource SAR image data well, reflects scattering, geometry, polarization, band and angle characteristics, and combines with analysis of the managed objects and service objects of the database as well as focuses on constructing SAR image system in the aspects of data browse and data retrieval. According the analysis of characteristics of SAR images such as scattering, polarization, incident angle and wave band information, different weights can be given to these characteristics. Then an interpreted tool is formed to provide an efficient platform for interpretation

  5. Magnetic resonance imaging evaluation after implantation of a titanium cervical disc prosthesis: a comparison of 1.5 and 3 Tesla magnet strength.

    Science.gov (United States)

    Sundseth, Jarle; Jacobsen, Eva A; Kolstad, Frode; Nygaard, Oystein P; Zwart, John A; Hol, Per K

    2013-10-01

    Cervical disc prostheses induce significant amount of artifact in magnetic resonance imaging which may complicate radiologic follow-up after surgery. The purpose of this study was to investigate as to what extent the artifact, induced by the frequently used Discover(®) cervical disc prosthesis, impedes interpretation of the MR images at operated and adjacent levels in 1.5 and 3 Tesla MR. Ten subsequent patients were investigated in both 1.5 and 3 Tesla MR with standard image sequences one year following anterior cervical discectomy with arthroplasty. Two neuroradiologists evaluated the images by consensus. Emphasis was made on signal changes in medulla at all levels and visualization of root canals at operated and adjacent levels. A "blur artifact ratio" was calculated and defined as the height of the artifact on T1 sagittal images related to the operated level. The artifacts induced in 1.5 and 3 Tesla MR were of entirely different character and evaluation of the spinal cord at operated level was impossible in both magnets. Artifacts also made the root canals difficult to assess at operated level and more pronounced in the 3 Tesla MR. At the adjacent levels however, the spinal cord and root canals were completely visualized in all patients. The "blur artifact" induced at operated level was also more pronounced in the 3 Tesla MR. The artifact induced by the Discover(®) titanium disc prosthesis in both 1.5 and 3 Tesla MR, makes interpretation of the spinal cord impossible and visualization of the root canals difficult at operated level. Adjusting the MR sequences to produce the least amount of artifact is important.

  6. Silhouette-based approach of 3D image reconstruction for automated image acquisition using robotic arm

    Science.gov (United States)

    Azhar, N.; Saad, W. H. M.; Manap, N. A.; Saad, N. M.; Syafeeza, A. R.

    2017-06-01

    This study presents the approach of 3D image reconstruction using an autonomous robotic arm for the image acquisition process. A low cost of the automated imaging platform is created using a pair of G15 servo motor connected in series to an Arduino UNO as a main microcontroller. Two sets of sequential images were obtained using different projection angle of the camera. The silhouette-based approach is used in this study for 3D reconstruction from the sequential images captured from several different angles of the object. Other than that, an analysis based on the effect of different number of sequential images on the accuracy of 3D model reconstruction was also carried out with a fixed projection angle of the camera. The effecting elements in the 3D reconstruction are discussed and the overall result of the analysis is concluded according to the prototype of imaging platform.

  7. Coupling News Sentiment with Web Browsing Data Improves Prediction of Intra-Day Price Dynamics.

    Science.gov (United States)

    Ranco, Gabriele; Bordino, Ilaria; Bormetti, Giacomo; Caldarelli, Guido; Lillo, Fabrizio; Treccani, Michele

    2016-01-01

    The new digital revolution of big data is deeply changing our capability of understanding society and forecasting the outcome of many social and economic systems. Unfortunately, information can be very heterogeneous in the importance, relevance, and surprise it conveys, affecting severely the predictive power of semantic and statistical methods. Here we show that the aggregation of web users' behavior can be elicited to overcome this problem in a hard to predict complex system, namely the financial market. Specifically, our in-sample analysis shows that the combined use of sentiment analysis of news and browsing activity of users of Yahoo! Finance greatly helps forecasting intra-day and daily price changes of a set of 100 highly capitalized US stocks traded in the period 2012-2013. Sentiment analysis or browsing activity when taken alone have very small or no predictive power. Conversely, when considering a news signal where in a given time interval we compute the average sentiment of the clicked news, weighted by the number of clicks, we show that for nearly 50% of the companies such signal Granger-causes hourly price returns. Our result indicates a "wisdom-of-the-crowd" effect that allows to exploit users' activity to identify and weigh properly the relevant and surprising news, enhancing considerably the forecasting power of the news sentiment.

  8. Coupling News Sentiment with Web Browsing Data Improves Prediction of Intra-Day Price Dynamics.

    Directory of Open Access Journals (Sweden)

    Gabriele Ranco

    Full Text Available The new digital revolution of big data is deeply changing our capability of understanding society and forecasting the outcome of many social and economic systems. Unfortunately, information can be very heterogeneous in the importance, relevance, and surprise it conveys, affecting severely the predictive power of semantic and statistical methods. Here we show that the aggregation of web users' behavior can be elicited to overcome this problem in a hard to predict complex system, namely the financial market. Specifically, our in-sample analysis shows that the combined use of sentiment analysis of news and browsing activity of users of Yahoo! Finance greatly helps forecasting intra-day and daily price changes of a set of 100 highly capitalized US stocks traded in the period 2012-2013. Sentiment analysis or browsing activity when taken alone have very small or no predictive power. Conversely, when considering a news signal where in a given time interval we compute the average sentiment of the clicked news, weighted by the number of clicks, we show that for nearly 50% of the companies such signal Granger-causes hourly price returns. Our result indicates a "wisdom-of-the-crowd" effect that allows to exploit users' activity to identify and weigh properly the relevant and surprising news, enhancing considerably the forecasting power of the news sentiment.

  9. Near-kHz 3D tracer-based LIF imaging of a co-flow jet using toluene

    International Nuclear Information System (INIS)

    Miller, V A; Troutman, V A; Hanson, R K

    2014-01-01

    This work demonstrates tracer-based, high-repetition-rate planar (15 kHz) and three-dimensional (940 Hz) laser-induced fluorescence imaging. An off-the-shelf, pulsed, frequency-quadrupled Nd:YAG laser at 266 nm is used as the excitation light source, and a high-frame-rate intensified relay optic with a slow P46 phosphor coupled to a CMOS camera is used to image the fluorescence. Four different tracers are investigated (3-pentanone, acetone, anisole, and toluene) and relative signal levels are measured in the potential core of a laminar co-flow jet. Resulting SNR values range from 6 to 44 for the different tracers, and relative signal levels and SNR for each tracer are provided as an engineering-basis for tracer-based imaging diagnostic design. It was found that signal levels from anisole (relative to toluene) are about ten times less than suggested by other literature, owing to uncertainty in the reported absorption cross sections. Using toluene as a tracer and a custom-made piezo-actuated steering optic to scan the laser sheet, 3D LIF imaging at 940 Hz is demonstrated by visualizing a co-flow jet mixing with ambient air. (paper)

  10. Low level cloud motion vectors from Kalpana-1 visible images

    Indian Academy of Sciences (India)

    . In this paper, an attempt has been made to retrieve low-level cloud motion vectors using Kalpana-1 visible (VIS) images at every half an hour. The VIS channel provides better detection of low level clouds, which remain obscure in thermal IR ...

  11. Research on Remote Sensing Image Classification Based on Feature Level Fusion

    Science.gov (United States)

    Yuan, L.; Zhu, G.

    2018-04-01

    Remote sensing image classification, as an important direction of remote sensing image processing and application, has been widely studied. However, in the process of existing classification algorithms, there still exists the phenomenon of misclassification and missing points, which leads to the final classification accuracy is not high. In this paper, we selected Sentinel-1A and Landsat8 OLI images as data sources, and propose a classification method based on feature level fusion. Compare three kind of feature level fusion algorithms (i.e., Gram-Schmidt spectral sharpening, Principal Component Analysis transform and Brovey transform), and then select the best fused image for the classification experimental. In the classification process, we choose four kinds of image classification algorithms (i.e. Minimum distance, Mahalanobis distance, Support Vector Machine and ISODATA) to do contrast experiment. We use overall classification precision and Kappa coefficient as the classification accuracy evaluation criteria, and the four classification results of fused image are analysed. The experimental results show that the fusion effect of Gram-Schmidt spectral sharpening is better than other methods. In four kinds of classification algorithms, the fused image has the best applicability to Support Vector Machine classification, the overall classification precision is 94.01 % and the Kappa coefficients is 0.91. The fused image with Sentinel-1A and Landsat8 OLI is not only have more spatial information and spectral texture characteristics, but also enhances the distinguishing features of the images. The proposed method is beneficial to improve the accuracy and stability of remote sensing image classification.

  12. 3D stereotaxis for epileptic foci through integrating MR imaging with neurological electrophysiology data

    International Nuclear Information System (INIS)

    Luo Min; Peng Chenglin; Wang Kang; Lei Wenyong; Luo Song; Wang Xiaolin; Wang Xuejian; Wu Ruoqiu; Wu Guofeng

    2005-01-01

    Objective: To improve the accuracy of the epilepsy diagnoses by integrating MR image from PACS with data from neurological electrophysiology. The integration is also very important for transmiting diagnostic information to 3D TPS of radiotherapy. Methods: The electroencephalogram was redisplayed by EEG workstation, while MR image was reconstructed by Brainvoyager software. 3D model of patient brain was built up by combining reconstructed images with electroencephalogram data in Base 2000. 30 epileptic patients (18 males and 12 females) with their age ranged from 12 to 54 years were confirmed by using the integrated MR images and the data from neurological electrophysiology and their 3D stereolocating. Results: The corresponding data in 3D model could show the real situation of patients' brain and visually locate the precise position of the focus. The suddessful rate of 3D guided operation was greatly improved, and the number of epileptic onset was markedly decreased. The epilepsy was stopped for 6 months in 8 of the 30 patients. Conclusion: The integration of MR image and information of neurological electrophysiology can improve the diagnostic level for epilepsy, and it is crucial for imp roving the successful rate of manipulations and the epilepsy analysis. (authors)

  13. MPEG-7 based video annotation and browsing

    Science.gov (United States)

    Hoeynck, Michael; Auweiler, Thorsten; Wellhausen, Jens

    2003-11-01

    The huge amount of multimedia data produced worldwide requires annotation in order to enable universal content access and to provide content-based search-and-retrieval functionalities. Since manual video annotation can be time consuming, automatic annotation systems are required. We review recent approaches to content-based indexing and annotation of videos for different kind of sports and describe our approach to automatic annotation of equestrian sports videos. We especially concentrate on MPEG-7 based feature extraction and content description, where we apply different visual descriptors for cut detection. Further, we extract the temporal positions of single obstacles on the course by analyzing MPEG-7 edge information. Having determined single shot positions as well as the visual highlights, the information is jointly stored with meta-textual information in an MPEG-7 description scheme. Based on this information, we generate content summaries which can be utilized in a user-interface in order to provide content-based access to the video stream, but further for media browsing on a streaming server.

  14. A novel hash based least significant bit (2-3-3) image steganography in spatial domain

    OpenAIRE

    Manjula, G. R.; Danti, Ajit

    2015-01-01

    This paper presents a novel 2-3-3 LSB insertion method. The image steganography takes the advantage of human eye limitation. It uses color image as cover media for embedding secret message.The important quality of a steganographic system is to be less distortive while increasing the size of the secret message. In this paper a method is proposed to embed a color secret image into a color cover image. A 2-3-3 LSB insertion method has been used for image steganography. Experimental results show ...

  15. Advanced Techniques in Web Intelligence-2 Web User Browsing Behaviour and Preference Analysis

    CERN Document Server

    Palade, Vasile; Jain, Lakhmi

    2013-01-01

    This research volume focuses on analyzing the web user browsing behaviour and preferences in traditional web-based environments, social  networks and web 2.0 applications,  by using advanced  techniques in data acquisition, data processing, pattern extraction and  cognitive science for modeling the human actions.  The book is directed to  graduate students, researchers/scientists and engineers  interested in updating their knowledge with the recent trends in web user analysis, for developing the next generation of web-based systems and applications.

  16. Two-Level Evaluation on Sensor Interoperability of Features in Fingerprint Image Segmentation

    Directory of Open Access Journals (Sweden)

    Ya-Shuo Li

    2012-03-01

    Full Text Available Features used in fingerprint segmentation significantly affect the segmentation performance. Various features exhibit different discriminating abilities on fingerprint images derived from different sensors. One feature which has better discriminating ability on images derived from a certain sensor may not adapt to segment images derived from other sensors. This degrades the segmentation performance. This paper empirically analyzes the sensor interoperability problem of segmentation feature, which refers to the feature’s ability to adapt to the raw fingerprints captured by different sensors. To address this issue, this paper presents a two-level feature evaluation method, including the first level feature evaluation based on segmentation error rate and the second level feature evaluation based on decision tree. The proposed method is performed on a number of fingerprint databases which are obtained from various sensors. Experimental results show that the proposed method can effectively evaluate the sensor interoperability of features, and the features with good evaluation results acquire better segmentation accuracies of images originating from different sensors.

  17. High-speed imaging at 3 tesla. A technical and clinical review with an emphasis on whole-brain 3D imaging

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Kawai, Hisashi; Fukatsu, Hiroshi; Ishigaki, Takeo; Komada, Tomomi

    2005-01-01

    Improvements to the inherently high specific-absorption rate (SAR) of high-speed imaging at 3T are necessary in order to render this method clinically feasible. Various efforts have been undertaken to improve the associated hardware and software. In this review, we focus on whole-brain isotropic 3D imaging with a turbo spin-echo sequence with variable flip-angle echo trains (3D-TSE-VFL) and present its technical and clinical features. This sequence can be used to acquire images of various contrasts including T 2 -weighted, fat-suppressed T 2 -weighted, fluid-attenuated inversion recovery (FLAIR), fat-suppressed FLAIR, and STIR (short tau inversion recovery). Various aspects of 3D-TSE-VFL are discussed, including CSF (cerebrospinal fluid) and metal artifacts, STIR contrast, small-part visualization other than brain, and the possibility of serial subtraction. Some images from clinical cases are presented. (author)

  18. Computed tomography imaging with the Adaptive Statistical Iterative Reconstruction (ASIR) algorithm: dependence of image quality on the blending level of reconstruction.

    Science.gov (United States)

    Barca, Patrizio; Giannelli, Marco; Fantacci, Maria Evelina; Caramella, Davide

    2018-06-01

    Computed tomography (CT) is a useful and widely employed imaging technique, which represents the largest source of population exposure to ionizing radiation in industrialized countries. Adaptive Statistical Iterative Reconstruction (ASIR) is an iterative reconstruction algorithm with the potential to allow reduction of radiation exposure while preserving diagnostic information. The aim of this phantom study was to assess the performance of ASIR, in terms of a number of image quality indices, when different reconstruction blending levels are employed. CT images of the Catphan-504 phantom were reconstructed using conventional filtered back-projection (FBP) and ASIR with reconstruction blending levels of 20, 40, 60, 80, and 100%. Noise, noise power spectrum (NPS), contrast-to-noise ratio (CNR) and modulation transfer function (MTF) were estimated for different scanning parameters and contrast objects. Noise decreased and CNR increased non-linearly up to 50 and 100%, respectively, with increasing blending level of reconstruction. Also, ASIR has proven to modify the NPS curve shape. The MTF of ASIR reconstructed images depended on tube load/contrast and decreased with increasing blending level of reconstruction. In particular, for low radiation exposure and low contrast acquisitions, ASIR showed lower performance than FBP, in terms of spatial resolution for all blending levels of reconstruction. CT image quality varies substantially with the blending level of reconstruction. ASIR has the potential to reduce noise whilst maintaining diagnostic information in low radiation exposure CT imaging. Given the opposite variation of CNR and spatial resolution with the blending level of reconstruction, it is recommended to use an optimal value of this parameter for each specific clinical application.

  19. Phenotypic feature quantification of patient derived 3D cancer spheroids in fluorescence microscopy image

    Science.gov (United States)

    Kang, Mi-Sun; Rhee, Seon-Min; Seo, Ji-Hyun; Kim, Myoung-Hee

    2017-03-01

    Patients' responses to a drug differ at the cellular level. Here, we present an image-based cell phenotypic feature quantification method for predicting the responses of patient-derived glioblastoma cells to a particular drug. We used high-content imaging to understand the features of patient-derived cancer cells. A 3D spheroid culture formation resembles the in vivo environment more closely than 2D adherent cultures do, and it allows for the observation of cellular aggregate characteristics. However, cell analysis at the individual level is more challenging. In this paper, we demonstrate image-based phenotypic screening of the nuclei of patient-derived cancer cells. We first stitched the images of each well of the 384-well plate with the same state. We then used intensity information to detect the colonies. The nuclear intensity and morphological characteristics were used for the segmentation of individual nuclei. Next, we calculated the position of each nucleus that is appeal of the spatial pattern of cells in the well environment. Finally, we compared the results obtained using 3D spheroid culture cells with those obtained using 2D adherent culture cells from the same patient being treated with the same drugs. This technique could be applied for image-based phenotypic screening of cells to determine the patient's response to the drug.

  20. 3D EIT image reconstruction with GREIT.

    Science.gov (United States)

    Grychtol, Bartłomiej; Müller, Beat; Adler, Andy

    2016-06-01

    Most applications of thoracic EIT use a single plane of electrodes on the chest from which a transverse image 'slice' is calculated. However, interpretation of EIT images is made difficult by the large region above and below the electrode plane to which EIT is sensitive. Volumetric EIT images using two (or more) electrode planes should help compensate, but are little used currently. The Graz consensus reconstruction algorithm for EIT (GREIT) has become popular in lung EIT. One shortcoming of the original formulation of GREIT is its restriction to reconstruction onto a 2D planar image. We present an extension of the GREIT algorithm to 3D and develop open-source tools to evaluate its performance as a function of the choice of stimulation and measurement pattern. Results show 3D GREIT using two electrode layers has significantly more uniform sensitivity profiles through the chest region. Overall, the advantages of 3D EIT are compelling.

  1. Level-set-based reconstruction algorithm for EIT lung images: first clinical results.

    Science.gov (United States)

    Rahmati, Peyman; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz; Adler, Andy

    2012-05-01

    We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure-volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM.

  2. Level-set-based reconstruction algorithm for EIT lung images: first clinical results

    International Nuclear Information System (INIS)

    Rahmati, Peyman; Adler, Andy; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz

    2012-01-01

    We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure–volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM. (paper)

  3. 2D vs. 3D imaging in laparoscopic surgery-results of a prospective randomized trial.

    Science.gov (United States)

    Buia, Alexander; Stockhausen, Florian; Filmann, Natalie; Hanisch, Ernst

    2017-12-01

    3D imaging is an upcoming technology in laparoscopic surgery, and recent studies have shown that the modern 3D technique is superior in an experimental setting. However, the first randomized controlled clinical trial in this context dates back to 1998 and showed no significant difference between 2D and 3D visualization using the first 3D generation technique, which is now more than 15 years old. Positive results measured in an experimental setting considering 3D imaging on surgical performance led us to initiate a randomized controlled pragmatic clinical trial to validate our findings in daily clinical routine. Standard laparoscopic operations (cholecystectomy, appendectomy) were preoperatively randomized to a 2D or 3D imaging system. We used a surgical comfort scale (Likert scale) and the Raw NASA Workload TLX for the subjective assessment of 2D and 3D imaging; the duration of surgery was also measured. The results of 3D imaging were statistically significant better than 2D imaging concerning the parameters "own felt safety" and "task efficiency"; the difficulty level of the procedures in the 2D and 3D groups did not differ. Overall, the Raw NASA Workload TLX showed no significance between the groups. 3D imaging could be a possible advantage in laparoscopic surgery. The results of our clinical trial show increased personal felt safety and efficiency of the surgeon using a 3D imaging system. Overall of the procedures, the findings assessed using Likert scales in terms of own felt safety and task efficiency were statistically significant for 3D imaging. The individually perceived workload assessed with the Raw NASA TLX shows no difference. Although these findings are subjective impressions of the performing surgeons without a clear benefit for 3D technology in clinical outcome, we think that these results show the capability that 3D laparoscopy can have a positive impact while performing laparoscopic procedures.

  4. Image-based RSA: Roentgen stereophotogrammetric analysis based on 2D-3D image registration.

    Science.gov (United States)

    de Bruin, P W; Kaptein, B L; Stoel, B C; Reiber, J H C; Rozing, P M; Valstar, E R

    2008-01-01

    Image-based Roentgen stereophotogrammetric analysis (IBRSA) integrates 2D-3D image registration and conventional RSA. Instead of radiopaque RSA bone markers, IBRSA uses 3D CT data, from which digitally reconstructed radiographs (DRRs) are generated. Using 2D-3D image registration, the 3D pose of the CT is iteratively adjusted such that the generated DRRs resemble the 2D RSA images as closely as possible, according to an image matching metric. Effectively, by registering all 2D follow-up moments to the same 3D CT, the CT volume functions as common ground. In two experiments, using RSA and using a micromanipulator as gold standard, IBRSA has been validated on cadaveric and sawbone scapula radiographs, and good matching results have been achieved. The accuracy was: |mu |RSA but higher than in vivo standard RSA. Because IBRSA does not require radiopaque markers, it adds functionality to the RSA method by opening new directions and possibilities for research, such as dynamic analyses using fluoroscopy on subjects without markers and computer navigation applications.

  5. Three-dimensional image technology in forensic anthropology: Assessing the validity of biological profiles derived from CT-3D images of the skeleton

    Science.gov (United States)

    Garcia de Leon Valenzuela, Maria Julia

    This project explores the reliability of building a biological profile for an unknown individual based on three-dimensional (3D) images of the individual's skeleton. 3D imaging technology has been widely researched for medical and engineering applications, and it is increasingly being used as a tool for anthropological inquiry. While the question of whether a biological profile can be derived from 3D images of a skeleton with the same accuracy as achieved when using dry bones has been explored, bigger sample sizes, a standardized scanning protocol and more interobserver error data are needed before 3D methods can become widely and confidently used in forensic anthropology. 3D images of Computed Tomography (CT) scans were obtained from 130 innominate bones from Boston University's skeletal collection (School of Medicine). For each bone, both 3D images and original bones were assessed using the Phenice and Suchey-Brooks methods. Statistical analysis was used to determine the agreement between 3D image assessment versus traditional assessment. A pool of six individuals with varying experience in the field of forensic anthropology scored a subsample (n = 20) to explore interobserver error. While a high agreement was found for age and sex estimation for specimens scored by the author, the interobserver study shows that observers found it difficult to apply standard methods to 3D images. Higher levels of experience did not result in higher agreement between observers, as would be expected. Thus, a need for training in 3D visualization before applying anthropological methods to 3D bones is suggested. Future research should explore interobserver error using a larger sample size in order to test the hypothesis that training in 3D visualization will result in a higher agreement between scores. The need for the development of a standard scanning protocol focusing on the optimization of 3D image resolution is highlighted. Applications for this research include the possibility

  6. 3D MODEL GENERATION USING OBLIQUE IMAGES ACQUIRED BY UAV

    Directory of Open Access Journals (Sweden)

    A. Lingua

    2017-07-01

    Full Text Available In recent years, many studies revealed the advantages of using airborne oblique images for obtaining improved 3D city models (including façades and building footprints. Here the acquisition and use of oblique images from a low cost and open source Unmanned Aerial Vehicle (UAV for the 3D high-level-of-detail reconstruction of historical architectures is evaluated. The critical issues of such acquisitions (flight planning strategies, ground control points distribution, etc. are described. Several problems should be considered in the flight planning: best approach to cover the whole object with the minimum time of flight; visibility of vertical structures; occlusions due to the context; acquisition of all the parts of the objects (the closest and the farthest with similar resolution; suitable camera inclination, and so on. In this paper a solution is proposed in order to acquire oblique images with one only flight. The data processing was realized using Structure-from-Motion-based approach for point cloud generation using dense image-matching algorithms implemented in an open source software. The achieved results are analysed considering some check points and some reference LiDAR data. The system was tested for surveying a historical architectonical complex: the “Sacro Mo nte di Varallo Sesia” in north-west of Italy. This study demonstrates that the use of oblique images acquired from a low cost UAV system and processed through an open source software is an effective methodology to survey cultural heritage, characterized by limited accessibility, need for detail and rapidity of the acquisition phase, and often reduced budgets.

  7. Effects of placement point of background music on shopping website.

    Science.gov (United States)

    Lai, Chien-Jung; Chiang, Chia-Chi

    2012-01-01

    Consumer on-line behaviors are more important than ever due to highly growth of on-line shopping. The purposes of this study were to design placement methods of background music for shopping website and examine the effect on browsers' emotional and cognitive response. Three placement points of background music during the browsing, i.e. 2 min., 4 min., and 6 min. from the start of browsing were considered for entry points. Both browsing without music (no music) and browsing with constant music volume (full music) were treated as control groups. Participants' emotional state, approach-avoidance behavior intention, and action to adjust music volume were collected. Results showed that participants had a higher level of pleasure, arousal and approach behavior intention for the three placement points than for no music and full music. Most of the participants for full music (5/6) adjusted the background music. Only 16.7% (3/18) participants for other levels turn off the background music. The results indicate that playing background music after the start of browsing is benefit for on-line shopping atmosphere. It is inappropriate to place background music at the start of browsing shopping website. The marketer must manipulated placement methods of background music for a web store carefully.

  8. 2D-3D image registration in diagnostic and interventional X-Ray imaging

    NARCIS (Netherlands)

    Bom, I.M.J. van der

    2010-01-01

    Clinical procedures that are conventionally guided by 2D x-ray imaging, may benefit from the additional spatial information provided by 3D image data. For instance, guidance of minimally invasive procedures with CT or MRI data provides 3D spatial information and visualization of structures that are

  9. Navigator-gated 3D blood oxygen level-dependent CMR at 3.0-T for detection of stress-induced myocardial ischemic reactions.

    Science.gov (United States)

    Jahnke, Cosima; Gebker, Rolf; Manka, Robert; Schnackenburg, Bernhard; Fleck, Eckart; Paetsch, Ingo

    2010-04-01

    This study determined the value of navigator-gated 3-dimensional blood oxygen level-dependent (BOLD) cardiac magnetic resonance (CMR) at 3.0-T for the detection of stress-induced myocardial ischemic reactions. Although BOLD CMR has been introduced for characterization of myocardial oxygenation status, previously reported CMR approaches suffered from a low signal-to-noise ratio and motion-related artifacts with impaired image quality and a limited diagnostic value in initial patient studies. Fifty patients with suspected or known coronary artery disease underwent CMR at 3.0-T followed by invasive X-ray angiography within 48 h. Three-dimensional BOLD images were acquired during free breathing with full coverage of the left ventricle in a short-axis orientation. The BOLD imaging was performed at rest and under adenosine stress, followed by stress and rest first-pass perfusion and delayed enhancement imaging. Quantitative coronary X-ray angiography (QCA) was used for coronary stenosis definition (diameter reduction > or =50%). The BOLD and first-pass perfusion images were semiquantitatively evaluated (for BOLD imaging, signal intensity differences between stress and rest [DeltaSI]; for perfusion imaging, myocardial perfusion reserve index [MPRI]). The image quality of BOLD CMR at rest and during adenosine stress was considered good to excellent in 90% and 84% of the patients, respectively. The DeltaSI measurements differed significantly between normal myocardium, myocardium supplied by a stenotic coronary artery, and infarcted myocardium (p exogenous contrast-enhancement studies. Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. EISCAT Aperture Synthesis Imaging (EASI _3D) for the EISCAT_3D Project

    Science.gov (United States)

    La Hoz, Cesar; Belyey, Vasyl

    2012-07-01

    Aperture Synthesis Imaging Radar (ASIR) is one of the technologies adopted by the EISCAT_3D project to endow it with imaging capabilities in 3-dimensions that includes sub-beam resolution. Complemented by pulse compression, it will provide 3-dimensional images of certain types of incoherent scatter radar targets resolved to about 100 metres at 100 km range, depending on the signal-to-noise ratio. This ability will open new research opportunities to map small structures associated with non-homogeneous, unstable processes such as aurora, summer and winter polar radar echoes (PMSE and PMWE), Natural Enhanced Ion Acoustic Lines (NEIALs), structures excited by HF ionospheric heating, meteors, space debris, and others. The underlying physico-mathematical principles of the technique are the same as the technique employed in radioastronomy to image stellar objects; both require sophisticated inversion techniques to obtain reliable images.

  11. Long-term in vivo imaging of multiple organs at the single cell level.

    Directory of Open Access Journals (Sweden)

    Benny J Chen

    Full Text Available Two-photon microscopy has enabled the study of individual cell behavior in live animals. Many organs and tissues cannot be studied, especially longitudinally, because they are located too deep, behind bony structures or too close to the lung and heart. Here we report a novel mouse model that allows long-term single cell imaging of many organs. A wide variety of live tissues were successfully engrafted in the pinna of the mouse ear. Many of these engrafted tissues maintained the normal tissue histology. Using the heart and thymus as models, we further demonstrated that the engrafted tissues functioned as would be expected. Combining two-photon microscopy with fluorescent tracers, we successfully visualized the engrafted tissues at the single cell level in live mice over several months. Four dimensional (three-dimensional (3D plus time information of individual cells was obtained from this imaging. This model makes long-term high resolution 4D imaging of multiple organs possible.

  12. Bit-level plane image encryption based on coupled map lattice with time-varying delay

    Science.gov (United States)

    Lv, Xiupin; Liao, Xiaofeng; Yang, Bo

    2018-04-01

    Most of the existing image encryption algorithms had two basic properties: confusion and diffusion in a pixel-level plane based on various chaotic systems. Actually, permutation in a pixel-level plane could not change the statistical characteristics of an image, and many of the existing color image encryption schemes utilized the same method to encrypt R, G and B components, which means that the three color components of a color image are processed three times independently. Additionally, dynamical performance of a single chaotic system degrades greatly with finite precisions in computer simulations. In this paper, a novel coupled map lattice with time-varying delay therefore is applied in color images bit-level plane encryption to solve the above issues. Spatiotemporal chaotic system with both much longer period in digitalization and much excellent performances in cryptography is recommended. Time-varying delay embedded in coupled map lattice enhances dynamical behaviors of the system. Bit-level plane image encryption algorithm has greatly reduced the statistical characteristics of an image through the scrambling processing. The R, G and B components cross and mix with one another, which reduces the correlation among the three components. Finally, simulations are carried out and all the experimental results illustrate that the proposed image encryption algorithm is highly secure, and at the same time, also demonstrates superior performance.

  13. PHOTOGRAMMETRIC 3D BUILDING RECONSTRUCTION FROM THERMAL IMAGES

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    E. Maset

    2017-08-01

    Full Text Available This paper addresses the problem of 3D building reconstruction from thermal infrared (TIR images. We show that a commercial Computer Vision software can be used to automatically orient sequences of TIR images taken from an Unmanned Aerial Vehicle (UAV and to generate 3D point clouds, without requiring any GNSS/INS data about position and attitude of the images nor camera calibration parameters. Moreover, we propose a procedure based on Iterative Closest Point (ICP algorithm to create a model that combines high resolution and geometric accuracy of RGB images with the thermal information deriving from TIR images. The process can be carried out entirely by the aforesaid software in a simple and efficient way.

  14. Contributions in compression of 3D medical images and 2D images; Contributions en compression d'images medicales 3D et d'images naturelles 2D

    Energy Technology Data Exchange (ETDEWEB)

    Gaudeau, Y

    2006-12-15

    The huge amounts of volumetric data generated by current medical imaging techniques in the context of an increasing demand for long term archiving solutions, as well as the rapid development of distant radiology make the use of compression inevitable. Indeed, if the medical community has sided until now with compression without losses, most of applications suffer from compression ratios which are too low with this kind of compression. In this context, compression with acceptable losses could be the most appropriate answer. So, we propose a new loss coding scheme based on 3D (3 dimensional) Wavelet Transform and Dead Zone Lattice Vector Quantization 3D (DZLVQ) for medical images. Our algorithm has been evaluated on several computerized tomography (CT) and magnetic resonance image volumes. The main contribution of this work is the design of a multidimensional dead zone which enables to take into account correlations between neighbouring elementary volumes. At high compression ratios, we show that it can out-perform visually and numerically the best existing methods. These promising results are confirmed on head CT by two medical patricians. The second contribution of this document assesses the effect with-loss image compression on CAD (Computer-Aided Decision) detection performance of solid lung nodules. This work on 120 significant lungs images shows that detection did not suffer until 48:1 compression and still was robust at 96:1. The last contribution consists in the complexity reduction of our compression scheme. The first allocation dedicated to 2D DZLVQ uses an exponential of the rate-distortion (R-D) functions. The second allocation for 2D and 3D medical images is based on block statistical model to estimate the R-D curves. These R-D models are based on the joint distribution of wavelet vectors using a multidimensional mixture of generalized Gaussian (MMGG) densities. (author)

  15. Training Methods for Image Noise Level Estimation on Wavelet Components

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    A. De Stefano

    2004-12-01

    Full Text Available The estimation of the standard deviation of noise contaminating an image is a fundamental step in wavelet-based noise reduction techniques. The method widely used is based on the mean absolute deviation (MAD. This model-based method assumes specific characteristics of the noise-contaminated image component. Three novel and alternative methods for estimating the noise standard deviation are proposed in this work and compared with the MAD method. Two of these methods rely on a preliminary training stage in order to extract parameters which are then used in the application stage. The sets used for training and testing, 13 and 5 images, respectively, are fully disjoint. The third method assumes specific statistical distributions for image and noise components. Results showed the prevalence of the training-based methods for the images and the range of noise levels considered.

  16. Seqcrawler: biological data indexing and browsing platform.

    Science.gov (United States)

    Sallou, Olivier; Bretaudeau, Anthony; Roult, Aurelien

    2012-07-24

    Seqcrawler takes its roots in software like SRS or Lucegene. It provides an indexing platform to ease the search of data and meta-data in biological banks and it can scale to face the current flow of data. While many biological bank search tools are available on the Internet, mainly provided by large organizations to search their data, there is a lack of free and open source solutions to browse one's own set of data with a flexible query system and able to scale from a single computer to a cloud system. A personal index platform will help labs and bioinformaticians to search their meta-data but also to build a larger information system with custom subsets of data. The software is scalable from a single computer to a cloud-based infrastructure. It has been successfully tested in a private cloud with 3 index shards (pieces of index) hosting ~400 millions of sequence information (whole GenBank, UniProt, PDB and others) for a total size of 600 GB in a fault tolerant architecture (high-availability). It has also been successfully integrated with software to add extra meta-data from blast results to enhance users' result analysis. Seqcrawler provides a complete open source search and store solution for labs or platforms needing to manage large amount of data/meta-data with a flexible and customizable web interface. All components (search engine, visualization and data storage), though independent, share a common and coherent data system that can be queried with a simple HTTP interface. The solution scales easily and can also provide a high availability infrastructure.

  17. Seqcrawler: biological data indexing and browsing platform

    Directory of Open Access Journals (Sweden)

    Sallou Olivier

    2012-07-01

    Full Text Available Abstract Background Seqcrawler takes its roots in software like SRS or Lucegene. It provides an indexing platform to ease the search of data and meta-data in biological banks and it can scale to face the current flow of data. While many biological bank search tools are available on the Internet, mainly provided by large organizations to search their data, there is a lack of free and open source solutions to browse one’s own set of data with a flexible query system and able to scale from a single computer to a cloud system. A personal index platform will help labs and bioinformaticians to search their meta-data but also to build a larger information system with custom subsets of data. Results The software is scalable from a single computer to a cloud-based infrastructure. It has been successfully tested in a private cloud with 3 index shards (pieces of index hosting ~400 millions of sequence information (whole GenBank, UniProt, PDB and others for a total size of 600 GB in a fault tolerant architecture (high-availability. It has also been successfully integrated with software to add extra meta-data from blast results to enhance users’ result analysis. Conclusions Seqcrawler provides a complete open source search and store solution for labs or platforms needing to manage large amount of data/meta-data with a flexible and customizable web interface. All components (search engine, visualization and data storage, though independent, share a common and coherent data system that can be queried with a simple HTTP interface. The solution scales easily and can also provide a high availability infrastructure.

  18. High speed display algorithm for 3D medical images using Multi Layer Range Image

    International Nuclear Information System (INIS)

    Ban, Hideyuki; Suzuki, Ryuuichi

    1993-01-01

    We propose high speed algorithm that display 3D voxel images obtained from medical imaging systems such as MRI. This algorithm convert voxel image data to 6 Multi Layer Range Image (MLRI) data, which is an augmentation of the range image data. To avoid the calculation for invisible voxels, the algorithm selects at most 3 MLRI data from 6 in accordance with the view direction. The proposed algorithm displays 256 x 256 x 256 voxel data within 0.6 seconds using 22 MIPS Workstation without a special hardware such as Graphics Engine. Real-time display will be possible on 100 MIPS class Workstation by our algorithm. (author)

  19. High performance 3D adaptive filtering for DSP based portable medical imaging systems

    Science.gov (United States)

    Bockenbach, Olivier; Ali, Murtaza; Wainwright, Ian; Nadeski, Mark

    2015-03-01

    Portable medical imaging devices have proven valuable for emergency medical services both in the field and hospital environments and are becoming more prevalent in clinical settings where the use of larger imaging machines is impractical. Despite their constraints on power, size and cost, portable imaging devices must still deliver high quality images. 3D adaptive filtering is one of the most advanced techniques aimed at noise reduction and feature enhancement, but is computationally very demanding and hence often cannot be run with sufficient performance on a portable platform. In recent years, advanced multicore digital signal processors (DSP) have been developed that attain high processing performance while maintaining low levels of power dissipation. These processors enable the implementation of complex algorithms on a portable platform. In this study, the performance of a 3D adaptive filtering algorithm on a DSP is investigated. The performance is assessed by filtering a volume of size 512x256x128 voxels sampled at a pace of 10 MVoxels/sec with an Ultrasound 3D probe. Relative performance and power is addressed between a reference PC (Quad Core CPU) and a TMS320C6678 DSP from Texas Instruments.

  20. Multi-stage 3D-2D registration for correction of anatomical deformation in image-guided spine surgery

    Science.gov (United States)

    Ketcha, M. D.; De Silva, T.; Uneri, A.; Jacobson, M. W.; Goerres, J.; Kleinszig, G.; Vogt, S.; Wolinsky, J.-P.; Siewerdsen, J. H.

    2017-06-01

    A multi-stage image-based 3D-2D registration method is presented that maps annotations in a 3D image (e.g. point labels annotating individual vertebrae in preoperative CT) to an intraoperative radiograph in which the patient has undergone non-rigid anatomical deformation due to changes in patient positioning or due to the intervention itself. The proposed method (termed msLevelCheck) extends a previous rigid registration solution (LevelCheck) to provide an accurate mapping of vertebral labels in the presence of spinal deformation. The method employs a multi-stage series of rigid 3D-2D registrations performed on sets of automatically determined and increasingly localized sub-images, with the final stage achieving a rigid mapping for each label to yield a locally rigid yet globally deformable solution. The method was evaluated first in a phantom study in which a CT image of the spine was acquired followed by a series of 7 mobile radiographs with increasing degree of deformation applied. Second, the method was validated using a clinical data set of patients exhibiting strong spinal deformation during thoracolumbar spine surgery. Registration accuracy was assessed using projection distance error (PDE) and failure rate (PDE  >  20 mm—i.e. label registered outside vertebra). The msLevelCheck method was able to register all vertebrae accurately for all cases of deformation in the phantom study, improving the maximum PDE of the rigid method from 22.4 mm to 3.9 mm. The clinical study demonstrated the feasibility of the approach in real patient data by accurately registering all vertebral labels in each case, eliminating all instances of failure encountered in the conventional rigid method. The multi-stage approach demonstrated accurate mapping of vertebral labels in the presence of strong spinal deformation. The msLevelCheck method maintains other advantageous aspects of the original LevelCheck method (e.g. compatibility with standard clinical workflow, large

  1. Evaluation of image quality and radiation dose by adaptive statistical iterative reconstruction technique level for chest CT examination.

    Science.gov (United States)

    Hong, Sun Suk; Lee, Jong-Woong; Seo, Jeong Beom; Jung, Jae-Eun; Choi, Jiwon; Kweon, Dae Cheol

    2013-12-01

    The purpose of this research is to determine the adaptive statistical iterative reconstruction (ASIR) level that enables optimal image quality and dose reduction in the chest computed tomography (CT) protocol with ASIR. A chest phantom with 0-50 % ASIR levels was scanned and then noise power spectrum (NPS), signal and noise and the degree of distortion of peak signal-to-noise ratio (PSNR) and the root-mean-square error (RMSE) were measured. In addition, the objectivity of the experiment was measured using the American College of Radiology (ACR) phantom. Moreover, on a qualitative basis, five lesions' resolution, latitude and distortion degree of chest phantom and their compiled statistics were evaluated. The NPS value decreased as the frequency increased. The lowest noise and deviation were at the 20 % ASIR level, mean 126.15 ± 22.21. As a result of the degree of distortion, signal-to-noise ratio and PSNR at 20 % ASIR level were at the highest value as 31.0 and 41.52. However, maximum absolute error and RMSE showed the lowest deviation value as 11.2 and 16. In the ACR phantom study, all ASIR levels were within acceptable allowance of guidelines. The 20 % ASIR level performed best in qualitative evaluation at five lesions of chest phantom as resolution score 4.3, latitude 3.47 and the degree of distortion 4.25. The 20 % ASIR level was proved to be the best in all experiments, noise, distortion evaluation using ImageJ and qualitative evaluation of five lesions of a chest phantom. Therefore, optimal images as well as reduce radiation dose would be acquired when 20 % ASIR level in thoracic CT is applied.

  2. Editorial: 3DIM-DS 2015: Optical image processing in the context of 3D imaging, metrology, and data security

    Science.gov (United States)

    Alfalou, Ayman

    2017-02-01

    Following the first International Symposium on 3D Imaging, Metrology, and Data Security (3DIM-DS) held in Shenzhen during september 2015, this special issue gathers a series of articles dealing with the main topics discussed during this symposium. These topics highlighted the importance of studying complex data treatment systems and intensive calculations designed for high dimensional imaging and metrology for which high image quality and high transmission speed become critical issues in a number of technological applications. A second purpose was to celebrate the International Year of Light by emphasizing the important role of optics in actual information processing systems.

  3. Wilderness ecology: the upland plant communities, woody browse production, and small mammals of two adjacent 33-year-old wildfire areas of northeastern Minnesota.

    Science.gov (United States)

    Lewis F. Ohmann; Charles T. Cushwa; Roger E. Lake; James R. Beer; Robert B. Brander

    1973-01-01

    In three parts, classifies the upland vegetation into four community types; describes the measurements of browse and gives yields by different species; and describes the relation of small mammal populations to vegetative community types.

  4. VERIFICATION OF 3D BUILDING MODELS USING MUTUAL INFORMATION IN AIRBORNE OBLIQUE IMAGES

    Directory of Open Access Journals (Sweden)

    A. P. Nyaruhuma

    2012-07-01

    Full Text Available This paper describes a method for automatic verification of 3D building models using airborne oblique images. The problem being tackled is identifying buildings that are demolished or changed since the models were constructed or identifying wrong models using the images. The models verified are of CityGML LOD2 or higher since their edges are expected to coincide with actual building edges. The verification approach is based on information theory. Corresponding variables between building models and oblique images are used for deriving mutual information for individual edges, faces or whole buildings, and combined for all perspective images available for the building. The wireframe model edges are projected to images and verified using low level image features – the image pixel gradient directions. A building part is only checked against images in which it may be visible. The method has been tested with models constructed using laser points against Pictometry images that are available for most cities of Europe and may be publically viewed in the so called Birds Eye view of the Microsoft Bing Maps. Results are that nearly all buildings are correctly categorised as existing or demolished. Because we now concentrate only on roofs we also used the method to test and compare results from nadir images. This comparison made clear that especially height errors in models can be more reliably detected in oblique images because of the tilted view. Besides overall building verification, results per individual edges can be used for improving the 3D building models.

  5. 3D surface reconstruction using optical flow for medical imaging

    International Nuclear Information System (INIS)

    Weng, Nan; Yang, Yee-Hong; Pierson, R.

    1996-01-01

    The recovery of a 3D model from a sequence of 2D images is very useful in medical image analysis. Image sequences obtained from the relative motion between the object and the camera or the scanner contain more 3D information than a single image. Methods to visualize the computed tomograms can be divided into two approaches: the surface rendering approach and the volume rendering approach. A new surface rendering method using optical flow is proposed. Optical flow is the apparent motion in the image plane produced by the projection of the real 3D motion onto 2D image. In this paper, the object remains stationary while the scanner undergoes translational motion. The 3D motion of an object can be recovered from the optical flow field using additional constraints. By extracting the surface information from 3D motion, it is possible to get an accurate 3D model of the object. Both synthetic and real image sequences have been used to illustrate the feasibility of the proposed method. The experimental results suggest that the proposed method is suitable for the reconstruction of 3D models from ultrasound medical images as well as other computed tomograms

  6. 3D Interpolation Method for CT Images of the Lung

    Directory of Open Access Journals (Sweden)

    Noriaki Asada

    2003-06-01

    Full Text Available A 3-D image can be reconstructed from numerous CT images of the lung. The procedure reconstructs a solid from multiple cross section images, which are collected during pulsation of the heart. Thus the motion of the heart is a special factor that must be taken into consideration during reconstruction. The lung exhibits a repeating transformation synchronized to the beating of the heart as an elastic body. There are discontinuities among neighboring CT images due to the beating of the heart, if no special techniques are used in taking CT images. The 3-D heart image is reconstructed from numerous CT images in which both the heart and the lung are taken. Although the outline shape of the reconstructed 3-D heart is quite unnatural, the envelope of the 3-D unnatural heart is fit to the shape of the standard heart. The envelopes of the lung in the CT images are calculated after the section images of the best fitting standard heart are located at the same positions of the CT images. Thus the CT images are geometrically transformed to the optimal CT images fitting best to the standard heart. Since correct transformation of images is required, an Area oriented interpolation method proposed by us is used for interpolation of transformed images. An attempt to reconstruct a 3-D lung image by a series of such operations without discontinuity is shown. Additionally, the same geometrical transformation method to the original projection images is proposed as a more advanced method.

  7. Simultaneous reconstruction, segmentation, and edge enhancement of relatively piecewise continuous images with intensity-level information

    International Nuclear Information System (INIS)

    Liang, Z.; Jaszczak, R.; Coleman, R.; Johnson, V.

    1991-01-01

    A multinomial image model is proposed which uses intensity-level information for reconstruction of contiguous image regions. The intensity-level information assumes that image intensities are relatively constant within contiguous regions over the image-pixel array and that intensity levels of these regions are determined either empirically or theoretically by information criteria. These conditions may be valid, for example, for cardiac blood-pool imaging, where the intensity levels (or radionuclide activities) of myocardium, blood-pool, and background regions are distinct and the activities within each region of muscle, blood, or background are relatively uniform. To test the model, a mathematical phantom over a 64x64 array was constructed. The phantom had three contiguous regions. Each region had a different intensity level. Measurements from the phantom were simulated using an emission-tomography geometry. Fifty projections were generated over 180 degree, with 64 equally spaced parallel rays per projection. Projection data were randomized to contain Poisson noise. Image reconstructions were performed using an iterative maximum a posteriori probability procedure. The contiguous regions corresponding to the three intensity levels were automatically segmented. Simultaneously, the edges of the regions were sharpened. Noise in the reconstructed images was significantly suppressed. Convergence of the iterative procedure to the phantom was observed. Compared with maximum likelihood and filtered-backprojection approaches, the results obtained using the maximum a posteriori probability with the intensity-level information demonstrated qualitative and quantitative improvement in localizing the regions of varying intensities

  8. Sketch-based 3D modeling by aligning outlines of an image

    Directory of Open Access Journals (Sweden)

    Chunxiao Li

    2016-07-01

    Full Text Available In this paper we present an efficient technique for sketch-based 3D modeling using automatically extracted image features. Creating a 3D model often requires a drawing of irregular shapes composed of curved lines as a starting point but it is difficult to hand-draw such lines without introducing awkward bumps and edges along the lines. We propose an automatic alignment of a user׳s hand-drawn sketch lines to the contour lines of an image, facilitating a considerable level of ease with which the user can carelessly continue sketching while the system intelligently snaps the sketch lines to a background image contour, no longer requiring the strenuous effort and stress of trying to make a perfect line during the modeling task. This interactive technique seamlessly combines the efficiency and perception of the human user with the accuracy of computational power, applied to the domain of 3D modeling where the utmost precision of on-screen drawing has been one of the hurdles of the task hitherto considered a job requiring a highly skilled and careful manipulation by the user. We provide several examples to demonstrate the accuracy and efficiency of the method with which complex shapes were achieved easily and quickly in the interactive outline drawing task.

  9. NaGdF4:Nd3+/Yb3+ Nanoparticles as Multimodal Imaging Agents

    Science.gov (United States)

    Pedraza, Francisco; Rightsell, Chris; Kumar, Ga; Giuliani, Jason; Monton, Car; Sardar, Dhiraj

    Medical imaging is a fundamental tool used for the diagnosis of numerous ailments. Each imaging modality has unique advantages; however, they possess intrinsic limitations. Some of which include low spatial resolution, sensitivity, penetration depth, and radiation damage. To circumvent this problem, the combination of imaging modalities, or multimodal imaging, has been proposed, such as Near Infrared Fluorescence imaging (NIRF) and Magnetic Resonance Imaging (MRI). Combining individual advantages, specificity and selectivity of NIRF with the deep penetration and high spatial resolution of MRI, it is possible to circumvent their shortcomings for a more robust imaging technique. In addition, both imaging modalities are very safe and minimally invasive. Fluorescent nanoparticles, such as NaGdF4:Nd3 +/Yb3 +, are excellent candidates for NIRF/MRI multimodal imaging. The dopants, Nd and Yb, absorb and emit within the biological window; where near infrared light is less attenuated by soft tissue. This results in less tissue damage and deeper tissue penetration making it a viable candidate in biological imaging. In addition, the inclusion of Gd results in paramagnetic properties, allowing their use as contrast agents in multimodal imaging. The work presented will include crystallographic results, as well as full optical and magnetic characterization to determine the nanoparticle's viability in multimodal imaging.

  10. Externally calibrated parallel imaging for 3D multispectral imaging near metallic implants using broadband ultrashort echo time imaging.

    Science.gov (United States)

    Wiens, Curtis N; Artz, Nathan S; Jang, Hyungseok; McMillan, Alan B; Reeder, Scott B

    2017-06-01

    To develop an externally calibrated parallel imaging technique for three-dimensional multispectral imaging (3D-MSI) in the presence of metallic implants. A fast, ultrashort echo time (UTE) calibration acquisition is proposed to enable externally calibrated parallel imaging techniques near metallic implants. The proposed calibration acquisition uses a broadband radiofrequency (RF) pulse to excite the off-resonance induced by the metallic implant, fully phase-encoded imaging to prevent in-plane distortions, and UTE to capture rapidly decaying signal. The performance of the externally calibrated parallel imaging reconstructions was assessed using phantoms and in vivo examples. Phantom and in vivo comparisons to self-calibrated parallel imaging acquisitions show that significant reductions in acquisition times can be achieved using externally calibrated parallel imaging with comparable image quality. Acquisition time reductions are particularly large for fully phase-encoded methods such as spectrally resolved fully phase-encoded three-dimensional (3D) fast spin-echo (SR-FPE), in which scan time reductions of up to 8 min were obtained. A fully phase-encoded acquisition with broadband excitation and UTE enabled externally calibrated parallel imaging for 3D-MSI, eliminating the need for repeated calibration regions at each frequency offset. Significant reductions in acquisition time can be achieved, particularly for fully phase-encoded methods like SR-FPE. Magn Reson Med 77:2303-2309, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  11. Image based 3D city modeling : Comparative study

    Directory of Open Access Journals (Sweden)

    S. P. Singh

    2014-06-01

    Full Text Available 3D city model is a digital representation of the Earth’s surface and it’s related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India. This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can’t do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good

  12. Two-level image authentication by two-step phase-shifting interferometry and compressive sensing

    Science.gov (United States)

    Zhang, Xue; Meng, Xiangfeng; Yin, Yongkai; Yang, Xiulun; Wang, Yurong; Li, Xianye; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

    2018-01-01

    A two-level image authentication method is proposed; the method is based on two-step phase-shifting interferometry, double random phase encoding, and compressive sensing (CS) theory, by which the certification image can be encoded into two interferograms. Through discrete wavelet transform (DWT), sparseness processing, Arnold transform, and data compression, two compressed signals can be generated and delivered to two different participants of the authentication system. Only the participant who possesses the first compressed signal attempts to pass the low-level authentication. The application of Orthogonal Match Pursuit CS algorithm reconstruction, inverse Arnold transform, inverse DWT, two-step phase-shifting wavefront reconstruction, and inverse Fresnel transform can result in the output of a remarkable peak in the central location of the nonlinear correlation coefficient distributions of the recovered image and the standard certification image. Then, the other participant, who possesses the second compressed signal, is authorized to carry out the high-level authentication. Therefore, both compressed signals are collected to reconstruct the original meaningful certification image with a high correlation coefficient. Theoretical analysis and numerical simulations verify the feasibility of the proposed method.

  13. Level set segmentation of medical images based on local region statistics and maximum a posteriori probability.

    Science.gov (United States)

    Cui, Wenchao; Wang, Yi; Lei, Tao; Fan, Yangyu; Feng, Yan

    2013-01-01

    This paper presents a variational level set method for simultaneous segmentation and bias field estimation of medical images with intensity inhomogeneity. In our model, the statistics of image intensities belonging to each different tissue in local regions are characterized by Gaussian distributions with different means and variances. According to maximum a posteriori probability (MAP) and Bayes' rule, we first derive a local objective function for image intensities in a neighborhood around each pixel. Then this local objective function is integrated with respect to the neighborhood center over the entire image domain to give a global criterion. In level set framework, this global criterion defines an energy in terms of the level set functions that represent a partition of the image domain and a bias field that accounts for the intensity inhomogeneity of the image. Therefore, image segmentation and bias field estimation are simultaneously achieved via a level set evolution process. Experimental results for synthetic and real images show desirable performances of our method.

  14. Effects of x-ray and CT image enhancements on the robustness and accuracy of a rigid 3D/2D image registration

    International Nuclear Information System (INIS)

    Kim, Jinkoo; Yin Fangfang; Zhao Yang; Kim, Jae Ho

    2005-01-01

    A rigid body three-dimensional/two-dimensional (3D/2D) registration method has been implemented using mutual information, gradient ascent, and 3D texturemap-based digitally reconstructed radiographs. Nine combinations of commonly used x-ray and computed tomography (CT) image enhancement methods, including window leveling, histogram equalization, and adaptive histogram equalization, were examined to assess their effects on accuracy and robustness of the registration method. From a set of experiments using an anthropomorphic chest phantom, we were able to draw several conclusions. First, the CT and x-ray preprocessing combination with the widest attraction range was the one that linearly stretched the histograms onto the entire display range on both CT and x-ray images. The average attraction ranges of this combination were 71.3 mm and 61.3 deg in the translation and rotation dimensions, respectively, and the average errors were 0.12 deg and 0.47 mm. Second, the combination of the CT image with tissue and bone information and the x-ray images with adaptive histogram equalization also showed subvoxel accuracy, especially the best in the translation dimensions. However, its attraction ranges were the smallest among the examined combinations (on average 36 mm and 19 deg). Last the bone-only information on the CT image did not show convergency property to the correct registration

  15. NASA's Global Imagery Browse Services - Technologies for Visualizing Earth Science Data

    Science.gov (United States)

    Cechini, M. F.; Boller, R. A.; Baynes, K.; Schmaltz, J. E.; Thompson, C. K.; Roberts, J. T.; Rodriguez, J.; Wong, M. M.; King, B. A.; King, J.; De Luca, A. P.; Pressley, N. N.

    2017-12-01

    For more than 20 years, the NASA Earth Observing System (EOS) has collected earth science data for thousands of scientific parameters now totaling nearly 15 Petabytes of data. In 2013, NASA's Global Imagery Browse Services (GIBS) formed its vision to "transform how end users interact and discover [EOS] data through visualizations." This vision included leveraging scientific and community best practices and standards to provide a scalable, compliant, and authoritative source for EOS earth science data visualizations. Since that time, GIBS has grown quickly and now services millions of daily requests for over 500 imagery layers representing hundreds of earth science parameters to a broad community of users. For many of these parameters, visualizations are available within hours of acquisition from the satellite. For others, visualizations are available for the entire mission of the satellite. The GIBS system is built upon the OnEarth and MRF open source software projects, which are provided by the GIBS team. This software facilitates standards-based access for compliance with existing GIS tools. The GIBS imagery layers are predominantly rasterized images represented in two-dimensional coordinate systems, though multiple projections are supported. The OnEarth software also supports the GIBS ingest pipeline to facilitate low latency updates to new or updated visualizations. This presentation will focus on the following topics: Overview of GIBS visualizations and user community Current benefits and limitations of the OnEarth and MRF software projects and related standards GIBS access methods and their in/compatibilities with existing GIS libraries and applications Considerations for visualization accuracy and understandability Future plans for more advanced visualization concepts including Vertical Profiles and Vector-Based Representations Future plans for Amazon Web Service support and deployments

  16. Contributions in compression of 3D medical images and 2D images

    International Nuclear Information System (INIS)

    Gaudeau, Y.

    2006-12-01

    The huge amounts of volumetric data generated by current medical imaging techniques in the context of an increasing demand for long term archiving solutions, as well as the rapid development of distant radiology make the use of compression inevitable. Indeed, if the medical community has sided until now with compression without losses, most of applications suffer from compression ratios which are too low with this kind of compression. In this context, compression with acceptable losses could be the most appropriate answer. So, we propose a new loss coding scheme based on 3D (3 dimensional) Wavelet Transform and Dead Zone Lattice Vector Quantization 3D (DZLVQ) for medical images. Our algorithm has been evaluated on several computerized tomography (CT) and magnetic resonance image volumes. The main contribution of this work is the design of a multidimensional dead zone which enables to take into account correlations between neighbouring elementary volumes. At high compression ratios, we show that it can out-perform visually and numerically the best existing methods. These promising results are confirmed on head CT by two medical patricians. The second contribution of this document assesses the effect with-loss image compression on CAD (Computer-Aided Decision) detection performance of solid lung nodules. This work on 120 significant lungs images shows that detection did not suffer until 48:1 compression and still was robust at 96:1. The last contribution consists in the complexity reduction of our compression scheme. The first allocation dedicated to 2D DZLVQ uses an exponential of the rate-distortion (R-D) functions. The second allocation for 2D and 3D medical images is based on block statistical model to estimate the R-D curves. These R-D models are based on the joint distribution of wavelet vectors using a multidimensional mixture of generalized Gaussian (MMGG) densities. (author)

  17. Mount St. Helens ash and mud: Chemical properties and effects on germination and establishment of trees and browse plants.

    Science.gov (United States)

    M.A. Radwan; Dan L. Campbell

    1981-01-01

    Chemical properties of ash and mud from the 1980 volcanic eruption of Mount St. Helens and their effect on germination and seedling production of selected plants were studied. The volcanic materials were low in some important nutrients and cation exchange capacity, and they adversely affected seedling production. Catsear, a preferred wildlife browse, and lodgepole pine...

  18. Real-time interpolation for true 3-dimensional ultrasound image volumes.

    Science.gov (United States)

    Ji, Songbai; Roberts, David W; Hartov, Alex; Paulsen, Keith D

    2011-02-01

    We compared trilinear interpolation to voxel nearest neighbor and distance-weighted algorithms for fast and accurate processing of true 3-dimensional ultrasound (3DUS) image volumes. In this study, the computational efficiency and interpolation accuracy of the 3 methods were compared on the basis of a simulated 3DUS image volume, 34 clinical 3DUS image volumes from 5 patients, and 2 experimental phantom image volumes. We show that trilinear interpolation improves interpolation accuracy over both the voxel nearest neighbor and distance-weighted algorithms yet achieves real-time computational performance that is comparable to the voxel nearest neighbor algrorithm (1-2 orders of magnitude faster than the distance-weighted algorithm) as well as the fastest pixel-based algorithms for processing tracked 2-dimensional ultrasound images (0.035 seconds per 2-dimesional cross-sectional image [76,800 pixels interpolated, or 0.46 ms/1000 pixels] and 1.05 seconds per full volume with a 1-mm(3) voxel size [4.6 million voxels interpolated, or 0.23 ms/1000 voxels]). On the basis of these results, trilinear interpolation is recommended as a fast and accurate interpolation method for rectilinear sampling of 3DUS image acquisitions, which is required to facilitate subsequent processing and display during operating room procedures such as image-guided neurosurgery.

  19. Educational outreach and impacts of white-tailed deer browse on native and invasive plants at the Crooked Creek Environmental Learning Center, Armstrong County, Pennsylvania

    Science.gov (United States)

    Lindsay, Lisa O.

    Overabundance of deer can assist the intrusion of invasive plants through browse, leading to homogenization of plant communities. Public attitudes towards native and invasive plant species and white-tailed deer browse related to personal experiences, can be changed through education focusing public awareness of ramifications of deer browse on native and invasive plants. I developed an interactive, interpretive Self-Guided Walking Tour brochure of the "You Can Trail" to provide an educational outreach program for visitors of Crooked Creek Environmental Learning Center that includes ecologically important native and invasive plants species from my investigation. This research study focuses on the overall abundance of native and invasive plant species once Odocoileus virginianus have been removed from the landscape during collection periods in June and September 2013 from exclosure and access plots that were maintained for seven years. Similarity of abundance were found in native and invasive abundance of forbs, bushes and percentage of ground cover. Differences included native bush volume being greater than invasive bush volume in the access plot in June with opposing results in the exclosure plot, being greater in invasive bush volume. However, in September, native and invasive bush volume was similar within the exclosure plot, while invasive bush volume decreased in the access plot. Invasive vines recorded in the June access plot were absent in the September collection period.

  20. Geophysical Imaging of Sea-level Proxies in Beach-Ridge Deposits

    Science.gov (United States)

    Nielsen, L.; Emerich Souza, P.; Meldgaard, A.; Bendixen, M.; Kroon, A.; Clemmensen, L. B.

    2017-12-01

    We show ground-penetrating radar (GPR) reflection data collected over modern and fossil beach deposits from different localities along coastlines in meso-tidal regimes of Greenland and micro-tidal regimes of Denmark. The acquired reflection GPR sections show several similar characteristics but also some differences. A similar characteristic is the presence of downlapping reflections, where the downlap point is interpreted to mark the transition from upper shoreface to beachface deposits and, thus, be a marker of a level close to or at sea-level at the time of deposition. Differences in grain size of the investigated beach ridge system result in different scattering characteristics of the acquired GPR data. These differences call for tailored, careful processing of the GPR data for optimal imaging of internal beach ridge architecture. We outline elements of the GPR data processing of particular importance for optimal imaging. Moreover, we discuss advantages and challenges related to using GPR-based proxies of sea-level as compared to other methods traditionally used for establishment of curves of past sea-level variation.

  1. Technical Note: Characterization of custom 3D printed multimodality imaging phantoms

    International Nuclear Information System (INIS)

    Bieniosek, Matthew F.; Lee, Brian J.; Levin, Craig S.

    2015-01-01

    Purpose: Imaging phantoms are important tools for researchers and technicians, but they can be costly and difficult to customize. Three dimensional (3D) printing is a widely available rapid prototyping technique that enables the fabrication of objects with 3D computer generated geometries. It is ideal for quickly producing customized, low cost, multimodal, reusable imaging phantoms. This work validates the use of 3D printed phantoms by comparing CT and PET scans of a 3D printed phantom and a commercial “Micro Deluxe” phantom. This report also presents results from a customized 3D printed PET/MRI phantom, and a customized high resolution imaging phantom with sub-mm features. Methods: CT and PET scans of a 3D printed phantom and a commercial Micro Deluxe (Data Spectrum Corporation, USA) phantom with 1.2, 1.6, 2.4, 3.2, 4.0, and 4.8 mm diameter hot rods were acquired. The measured PET and CT rod sizes, activities, and attenuation coefficients were compared. A PET/MRI scan of a custom 3D printed phantom with hot and cold rods was performed, with photon attenuation and normalization measurements performed with a separate 3D printed normalization phantom. X-ray transmission scans of a customized two level high resolution 3D printed phantom with sub-mm features were also performed. Results: Results show very good agreement between commercial and 3D printed micro deluxe phantoms with less than 3% difference in CT measured rod diameter, less than 5% difference in PET measured rod diameter, and a maximum of 6.2% difference in average rod activity from a 10 min, 333 kBq/ml (9 μCi/ml) Siemens Inveon (Siemens Healthcare, Germany) PET scan. In all cases, these differences were within the measurement uncertainties of our setups. PET/MRI scans successfully identified 3D printed hot and cold rods on PET and MRI modalities. X-ray projection images of a 3D printed high resolution phantom identified features as small as 350 μm wide. Conclusions: This work shows that 3D printed

  2. Technical Note: Characterization of custom 3D printed multimodality imaging phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Bieniosek, Matthew F. [Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, California 94305 (United States); Lee, Brian J. [Department of Mechanical Engineering, Stanford University, 440 Escondido Mall, Stanford, California 94305 (United States); Levin, Craig S., E-mail: cslevin@stanford.edu [Departments of Radiology, Physics, Bioengineering and Electrical Engineering, Stanford University, 300 Pasteur Dr., Stanford, California 94305-5128 (United States)

    2015-10-15

    Purpose: Imaging phantoms are important tools for researchers and technicians, but they can be costly and difficult to customize. Three dimensional (3D) printing is a widely available rapid prototyping technique that enables the fabrication of objects with 3D computer generated geometries. It is ideal for quickly producing customized, low cost, multimodal, reusable imaging phantoms. This work validates the use of 3D printed phantoms by comparing CT and PET scans of a 3D printed phantom and a commercial “Micro Deluxe” phantom. This report also presents results from a customized 3D printed PET/MRI phantom, and a customized high resolution imaging phantom with sub-mm features. Methods: CT and PET scans of a 3D printed phantom and a commercial Micro Deluxe (Data Spectrum Corporation, USA) phantom with 1.2, 1.6, 2.4, 3.2, 4.0, and 4.8 mm diameter hot rods were acquired. The measured PET and CT rod sizes, activities, and attenuation coefficients were compared. A PET/MRI scan of a custom 3D printed phantom with hot and cold rods was performed, with photon attenuation and normalization measurements performed with a separate 3D printed normalization phantom. X-ray transmission scans of a customized two level high resolution 3D printed phantom with sub-mm features were also performed. Results: Results show very good agreement between commercial and 3D printed micro deluxe phantoms with less than 3% difference in CT measured rod diameter, less than 5% difference in PET measured rod diameter, and a maximum of 6.2% difference in average rod activity from a 10 min, 333 kBq/ml (9 μCi/ml) Siemens Inveon (Siemens Healthcare, Germany) PET scan. In all cases, these differences were within the measurement uncertainties of our setups. PET/MRI scans successfully identified 3D printed hot and cold rods on PET and MRI modalities. X-ray projection images of a 3D printed high resolution phantom identified features as small as 350 μm wide. Conclusions: This work shows that 3D printed

  3. Technical Note: Characterization of custom 3D printed multimodality imaging phantoms.

    Science.gov (United States)

    Bieniosek, Matthew F; Lee, Brian J; Levin, Craig S

    2015-10-01

    Imaging phantoms are important tools for researchers and technicians, but they can be costly and difficult to customize. Three dimensional (3D) printing is a widely available rapid prototyping technique that enables the fabrication of objects with 3D computer generated geometries. It is ideal for quickly producing customized, low cost, multimodal, reusable imaging phantoms. This work validates the use of 3D printed phantoms by comparing CT and PET scans of a 3D printed phantom and a commercial "Micro Deluxe" phantom. This report also presents results from a customized 3D printed PET/MRI phantom, and a customized high resolution imaging phantom with sub-mm features. CT and PET scans of a 3D printed phantom and a commercial Micro Deluxe (Data Spectrum Corporation, USA) phantom with 1.2, 1.6, 2.4, 3.2, 4.0, and 4.8 mm diameter hot rods were acquired. The measured PET and CT rod sizes, activities, and attenuation coefficients were compared. A PET/MRI scan of a custom 3D printed phantom with hot and cold rods was performed, with photon attenuation and normalization measurements performed with a separate 3D printed normalization phantom. X-ray transmission scans of a customized two level high resolution 3D printed phantom with sub-mm features were also performed. Results show very good agreement between commercial and 3D printed micro deluxe phantoms with less than 3% difference in CT measured rod diameter, less than 5% difference in PET measured rod diameter, and a maximum of 6.2% difference in average rod activity from a 10 min, 333 kBq/ml (9 μCi/ml) Siemens Inveon (Siemens Healthcare, Germany) PET scan. In all cases, these differences were within the measurement uncertainties of our setups. PET/MRI scans successfully identified 3D printed hot and cold rods on PET and MRI modalities. X-ray projection images of a 3D printed high resolution phantom identified features as small as 350 μm wide. This work shows that 3D printed phantoms can be functionally equivalent to

  4. 3D Reconstruction of NMR Images by LabVIEW

    Directory of Open Access Journals (Sweden)

    Peter IZAK

    2007-01-01

    Full Text Available This paper introduces the experiment of 3D reconstruction NMR images via virtual instrumentation - LabVIEW. The main idea is based on marching cubes algorithm and image processing implemented by module of Vision assistant. The two dimensional images shot by the magnetic resonance device provide information about the surface properties of human body. There is implemented algorithm which can be used for 3D reconstruction of magnetic resonance images in biomedical application.

  5. Handbook of 3D machine vision optical metrology and imaging

    CERN Document Server

    Zhang, Song

    2013-01-01

    With the ongoing release of 3D movies and the emergence of 3D TVs, 3D imaging technologies have penetrated our daily lives. Yet choosing from the numerous 3D vision methods available can be frustrating for scientists and engineers, especially without a comprehensive resource to consult. Filling this gap, Handbook of 3D Machine Vision: Optical Metrology and Imaging gives an extensive, in-depth look at the most popular 3D imaging techniques. It focuses on noninvasive, noncontact optical methods (optical metrology and imaging). The handbook begins with the well-studied method of stereo vision and

  6. Direct Fourier imaging of distortions in LaAlO{sub 3} films

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, Christoph; Zegenhagen, Joerg [ESRF, Grenoble (France); Lee, Tien-Lin [Diamond Light Source Ltd, Didcot (United Kingdom); Aruta, Carmela [CNR-SPIN, Naples (Italy)

    2012-07-01

    The formation of a quasi-2dimensional electron gas at interface of SrTiO{sub 3} (STO) and LaAlO{sub 3} (LAO) attracted considerable attention in the recent years. The polar LAO layer was expected to cause the build-up of an electric potential. Distortions in the overlayer are discussed as one possible response of the system. The highly sensitive X-ray standing wave (XSW) imaging technique is well suited to study theses films because of its chemical and spacial resolution. LAO thin films below and above the critical thickness for conductivity were studied at the hard X-ray photo electron spectroscopy end station of ID32 at the ESRF. The XSW modulated core level photo electron yield was recorded for the five elements present in film and substrate for seven different Bragg reflections. Subsequent analysis provided for each reflection and element the amplitude and phase of one Fourier coefficient of the elemental atomic distribution function. The three dimensional real space image of the atomic distribution for each of the elements is reconstructed by direct Fourier inversion. The reconstructed 3D images obtained by this model free approach reveal significant atomic displacements.

  7. 3D Seismic Imaging using Marchenko Methods

    Science.gov (United States)

    Lomas, A.; Curtis, A.

    2017-12-01

    Marchenko methods are novel, data driven techniques that allow seismic wavefields from sources and receivers on the Earth's surface to be redatumed to construct wavefields with sources in the subsurface - including complex multiply-reflected waves, and without the need for a complex reference model. In turn, this allows subsurface images to be constructed at any such subsurface redatuming points (image or virtual receiver points). Such images are then free of artefacts from multiply-scattered waves that usually contaminate migrated seismic images. Marchenko algorithms require as input the same information as standard migration methods: the full reflection response from sources and receivers at the Earth's surface, and an estimate of the first arriving wave between the chosen image point and the surface. The latter can be calculated using a smooth velocity model estimated using standard methods. The algorithm iteratively calculates a signal that focuses at the image point to create a virtual source at that point, and this can be used to retrieve the signal between the virtual source and the surface. A feature of these methods is that the retrieved signals are naturally decomposed into up- and down-going components. That is, we obtain both the signal that initially propagated upwards from the virtual source and arrived at the surface, separated from the signal that initially propagated downwards. Figure (a) shows a 3D subsurface model with a variable density but a constant velocity (3000m/s). Along the surface of this model (z=0) in both the x and y directions are co-located sources and receivers at 20-meter intervals. The redatumed signal in figure (b) has been calculated using Marchenko methods from a virtual source (1200m, 500m and 400m) to the surface. For comparison the true solution is given in figure (c), and shows a good match when compared to figure (b). While these 2D redatuming and imaging methods are still in their infancy having first been developed in

  8. Image of а head of law-enforcement body on micro level (empirical experimentation

    Directory of Open Access Journals (Sweden)

    D. G. Perednya

    2016-01-01

    Full Text Available The article determines image of the head of law-enforcement body. Subjects and objects of image are described. Inhomogenuity of image is cleared up. Method of examination is shortly micro level described. It is talking about image, which is formed in mind of members of team of law-enforcement body, who are subordinated to object of image. State-of-the-art is illustrated, according to received data. Hypothesis about negative image of the head in mind of subordinates is disproved. It is shown contradiction of images in collective mind and social mind.

  9. Image processing on the image with pixel noise bits removed

    Science.gov (United States)

    Chuang, Keh-Shih; Wu, Christine

    1992-06-01

    Our previous studies used statistical methods to assess the noise level in digital images of various radiological modalities. We separated the pixel data into signal bits and noise bits and demonstrated visually that the removal of the noise bits does not affect the image quality. In this paper we apply image enhancement techniques on noise-bits-removed images and demonstrate that the removal of noise bits has no effect on the image property. The image processing techniques used are gray-level look up table transformation, Sobel edge detector, and 3-D surface display. Preliminary results show no noticeable difference between original image and noise bits removed image using look up table operation and Sobel edge enhancement. There is a slight enhancement of the slicing artifact in the 3-D surface display of the noise bits removed image.

  10. Intravital imaging of cardiac function at the single-cell level.

    Science.gov (United States)

    Aguirre, Aaron D; Vinegoni, Claudio; Sebas, Matt; Weissleder, Ralph

    2014-08-05

    Knowledge of cardiomyocyte biology is limited by the lack of methods to interrogate single-cell physiology in vivo. Here we show that contracting myocytes can indeed be imaged with optical microscopy at high temporal and spatial resolution in the beating murine heart, allowing visualization of individual sarcomeres and measurement of the single cardiomyocyte contractile cycle. Collectively, this has been enabled by efficient tissue stabilization, a prospective real-time cardiac gating approach, an image processing algorithm for motion-artifact-free imaging throughout the cardiac cycle, and a fluorescent membrane staining protocol. Quantification of cardiomyocyte contractile function in vivo opens many possibilities for investigating myocardial disease and therapeutic intervention at the cellular level.

  11. Rainbow particle imaging velocimetry for dense 3D fluid velocity imaging

    KAUST Repository

    Xiong, Jinhui

    2017-07-21

    Despite significant recent progress, dense, time-resolved imaging of complex, non-stationary 3D flow velocities remains an elusive goal. In this work we tackle this problem by extending an established 2D method, Particle Imaging Velocimetry, to three dimensions by encoding depth into color. The encoding is achieved by illuminating the flow volume with a continuum of light planes (a

  12. A Study of Light Level Effect on the Accuracy of Image Processing-based Tomato Grading

    Science.gov (United States)

    Prijatna, D.; Muhaemin, M.; Wulandari, R. P.; Herwanto, T.; Saukat, M.; Sugandi, W. K.

    2018-05-01

    Image processing method has been used in non-destructive tests of agricultural products. Compared to manual method, image processing method may produce more objective and consistent results. Image capturing box installed in currently used tomato grading machine (TEP-4) is equipped with four fluorescence lamps to illuminate the processed tomatoes. Since the performance of any lamp will decrease if its service time has exceeded its lifetime, it is predicted that this will affect tomato classification. The objective of this study was to determine the minimum light levels which affect classification accuracy. This study was conducted by varying light level from minimum and maximum on tomatoes in image capturing boxes and then investigates its effects on image characteristics. Research results showed that light intensity affects two variables which are important for classification, for example, area and color of captured image. Image processing program was able to determine correctly the weight and classification of tomatoes when light level was 30 lx to 140 lx.

  13. A color fusion method of infrared and low-light-level images based on visual perception

    Science.gov (United States)

    Han, Jing; Yan, Minmin; Zhang, Yi; Bai, Lianfa

    2014-11-01

    The color fusion images can be obtained through the fusion of infrared and low-light-level images, which will contain both the information of the two. The fusion images can help observers to understand the multichannel images comprehensively. However, simple fusion may lose the target information due to inconspicuous targets in long-distance infrared and low-light-level images; and if targets extraction is adopted blindly, the perception of the scene information will be affected seriously. To solve this problem, a new fusion method based on visual perception is proposed in this paper. The extraction of the visual targets ("what" information) and parallel processing mechanism are applied in traditional color fusion methods. The infrared and low-light-level color fusion images are achieved based on efficient typical targets learning. Experimental results show the effectiveness of the proposed method. The fusion images achieved by our algorithm can not only improve the detection rate of targets, but also get rich natural information of the scenes.

  14. Analysis of gene expression levels in individual bacterial cells without image segmentation.

    Science.gov (United States)

    Kwak, In Hae; Son, Minjun; Hagen, Stephen J

    2012-05-11

    Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Influence of Geomorphology on the Physiognomy of Colophospermum mopane and its Effect on Browsing in Central Namibia

    OpenAIRE

    TESHIROGI, Koki

    2010-01-01

    Colophospermum mopane is a characteristic tree species indigenous to Southern Africa, where it forms 'mopane vegetation.' Mopane plays an important role in livestock farming, and the physiognomy of mopane influences the availability of feed. This study clarified the relationship between the difference in mopane physiognomy and the browsing activity of goats with reference to geomorphology. The physiognomy of mopane corresponded to geomorphological characteristics of surface structures and soi...

  16. Advanced 3-D Ultrasound Imaging: 3-D Synthetic Aperture Imaging using Fully Addressed and Row-Column Addressed 2-D Transducer Arrays

    DEFF Research Database (Denmark)

    Bouzari, Hamed

    the important diagnostic information in a noninvasive manner. Diagnostic and therapeutic decisions often require accurate estimates of e.g., organ, cyst, or tumor volumes. 3-D ultrasound imaging can provide these measurements without relying on the geometrical assumptions and operator-dependent skills involved...... is one of the factors for the widespread use of ultrasound imaging. The high price tag on the high quality 3-D scanners is limiting their market share. Row-column addressing of 2-D transducer arrays is a low cost alternative to fully addressed 2-D arrays, for 3-D ultrasound imaging. Using row....... Based on a set of acoustical measurements the center frequency, bandwidth, surface pressure, sensitivity, and acoustical cross-talks were evaluated and discussed. The imaging quality assessments were carried out based on Field II simulations as well as phantom measurements. Moreover, an analysis...

  17. The evaluation of single-view and multi-view fusion 3D echocardiography using image-driven segmentation and tracking.

    Science.gov (United States)

    Rajpoot, Kashif; Grau, Vicente; Noble, J Alison; Becher, Harald; Szmigielski, Cezary

    2011-08-01

    Real-time 3D echocardiography (RT3DE) promises a more objective and complete cardiac functional analysis by dynamic 3D image acquisition. Despite several efforts towards automation of left ventricle (LV) segmentation and tracking, these remain challenging research problems due to the poor-quality nature of acquired images usually containing missing anatomical information, speckle noise, and limited field-of-view (FOV). Recently, multi-view fusion 3D echocardiography has been introduced as acquiring multiple conventional single-view RT3DE images with small probe movements and fusing them together after alignment. This concept of multi-view fusion helps to improve image quality and anatomical information and extends the FOV. We now take this work further by comparing single-view and multi-view fused images in a systematic study. In order to better illustrate the differences, this work evaluates image quality and information content of single-view and multi-view fused images using image-driven LV endocardial segmentation and tracking. The image-driven methods were utilized to fully exploit image quality and anatomical information present in the image, thus purposely not including any high-level constraints like prior shape or motion knowledge in the analysis approaches. Experiments show that multi-view fused images are better suited for LV segmentation and tracking, while relatively more failures and errors were observed on single-view images. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Multiple-aperture optical design for micro-level cameras using 3D-printing method

    Science.gov (United States)

    Peng, Wei-Jei; Hsu, Wei-Yao; Cheng, Yuan-Chieh; Lin, Wen-Lung; Yu, Zong-Ru; Chou, Hsiao-Yu; Chen, Fong-Zhi; Fu, Chien-Chung; Wu, Chong-Syuan; Huang, Chao-Tsung

    2018-02-01

    The design of the ultra miniaturized camera using 3D-printing technology directly printed on to the complementary metal-oxide semiconductor (CMOS) imaging sensor is presented in this paper. The 3D printed micro-optics is manufactured using the femtosecond two-photon direct laser writing, and the figure error which could achieve submicron accuracy is suitable for the optical system. Because the size of the micro-level camera is approximately several hundreds of micrometers, the resolution is reduced much and highly limited by the Nyquist frequency of the pixel pitch. For improving the reduced resolution, one single-lens can be replaced by multiple-aperture lenses with dissimilar field of view (FOV), and then stitching sub-images with different FOV can achieve a high resolution within the central region of the image. The reason is that the angular resolution of the lens with smaller FOV is higher than that with larger FOV, and then the angular resolution of the central area can be several times than that of the outer area after stitching. For the same image circle, the image quality of the central area of the multi-lens system is significantly superior to that of a single-lens. The foveated image using stitching FOV breaks the limitation of the resolution for the ultra miniaturized imaging system, and then it can be applied such as biomedical endoscopy, optical sensing, and machine vision, et al. In this study, the ultra miniaturized camera with multi-aperture optics is designed and simulated for the optimum optical performance.

  19. Local gray level S-curve transformation - A generalized contrast enhancement technique for medical images.

    Science.gov (United States)

    Gandhamal, Akash; Talbar, Sanjay; Gajre, Suhas; Hani, Ahmad Fadzil M; Kumar, Dileep

    2017-04-01

    Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A New Approach of an Intelligent E-Learning System Based on Learners' Skill Level and Learners' Success Rate

    Science.gov (United States)

    Mohamed, Hafidi; Lamia, Mahnane

    2015-01-01

    Learners usually meet cognitive overload and disorientation problems when using e-learning system. At present, most of the studies in e-learning either concentrate on the technological aspect or focus on adapting learner's interests or browsing behaviors, while, learner's skill level and learners' success rate is usually neglected. In this paper,…

  1. Robust boundary detection of left ventricles on ultrasound images using ASM-level set method.

    Science.gov (United States)

    Zhang, Yaonan; Gao, Yuan; Li, Hong; Teng, Yueyang; Kang, Yan

    2015-01-01

    Level set method has been widely used in medical image analysis, but it has difficulties when being used in the segmentation of left ventricular (LV) boundaries on echocardiography images because the boundaries are not very distinguish, and the signal-to-noise ratio of echocardiography images is not very high. In this paper, we introduce the Active Shape Model (ASM) into the traditional level set method to enforce shape constraints. It improves the accuracy of boundary detection and makes the evolution more efficient. The experiments conducted on the real cardiac ultrasound image sequences show a positive and promising result.

  2. Effect of Task-Correlated Physiological Fluctuations and Motion in 2D and 3D Echo-Planar Imaging in a Higher Cognitive Level fMRI Paradigm.

    Science.gov (United States)

    Ladstein, Jarle; Evensmoen, Hallvard R; Håberg, Asta K; Kristoffersen, Anders; Goa, Pål E

    2016-01-01

    To compare 2D and 3D echo-planar imaging (EPI) in a higher cognitive level fMRI paradigm. In particular, to study the link between the presence of task-correlated physiological fluctuations and motion and the fMRI contrast estimates from either 2D EPI or 3D EPI datasets, with and without adding nuisance regressors to the model. A signal model in the presence of partly task-correlated fluctuations is derived, and predictions for contrast estimates with and without nuisance regressors are made. Thirty-one healthy volunteers were scanned using 2D EPI and 3D EPI during a virtual environmental learning paradigm. In a subgroup of 7 subjects, heart rate and respiration were logged, and the correlation with the paradigm was evaluated. FMRI analysis was performed using models with and without nuisance regressors. Differences in the mean contrast estimates were investigated by analysis-of-variance using Subject, Sequence, Day, and Run as factors. The distributions of group level contrast estimates were compared. Partially task-correlated fluctuations in respiration, heart rate and motion were observed. Statistically significant differences were found in the mean contrast estimates between the 2D EPI and 3D EPI when using a model without nuisance regressors. The inclusion of nuisance regressors for cardiorespiratory effects and motion reduced the difference to a statistically non-significant level. Furthermore, the contrast estimate values shifted more when including nuisance regressors for 3D EPI compared to 2D EPI. The results are consistent with 3D EPI having a higher sensitivity to fluctuations compared to 2D EPI. In the presence partially task-correlated physiological fluctuations or motion, proper correction is necessary to get expectation correct contrast estimates when using 3D EPI. As such task-correlated physiological fluctuations or motion is difficult to avoid in paradigms exploring higher cognitive functions, 2D EPI seems to be the preferred choice for higher

  3. The preliminary results of the diagnosis of pituitary diseases using 13N-NH3 PET dynamic imaging

    International Nuclear Information System (INIS)

    Zhang Xiangsong; Chen Hongmei; Yang Huazhang; Tang Anwu; Qiao Suixian

    2002-01-01

    Objective: To preliminarily evaluate the value of 13 N-NH 3 PET dynamic imaging for the diagnosis of pituitary diseases. Methods: The 13 N-NH 3 PET dynamic imaging was performed on 2 patients with pituitary microadenoma and one patient with hypopituitarism, the diagnoses were confirmed by MRI, levels of relative endocrine hormones in blood and clinical presentations. Results: In 2 patients with pituitary microadenoma, the pituitaries were seen in 20 and 30 s after the internal carotid was seen in the dynamic PET images, the upper margins of pituitaries were convex, the heights were 1.75 cm and 1.62 cm, the standard uptake values (SUVs) of pituitaries were 3.96 and 3.28, and the radioactivity ratio of pituitary to thalamus were 1.58 and 1.27. In the patient with hypopituitarism, the pituitary was seen at 3 min after the image of the internal carotid, the image of pituitary was smaller than the normal ones (0.82 cm x 0.83 cm x 1.03 cm), the SUV of pituitary was 1.48, and the radioactivity ratio of pituitary to thalamus was 0.64. Conclusion: The 13 N-NH 3 PET dynamic imaging is useful in diagnosing pituitary microadenoma and hypopituitarism

  4. 3.0-T high-field magnetic resonance imaging of the female pelvis: preliminary experiences

    International Nuclear Information System (INIS)

    Morakkabati-Spitz, N.; Gieseke, J.; Kuhl, C.; Lutterbey, G.; Falkenhausen, M. von; Traeber, F.; Zivanovic, O.; Schild, H.H.

    2005-01-01

    The purpose of this study was to evaluate if 3.0 T allows for clinically useful pelvic magnetic resonance imaging, i.e. if familiar image quality and tissue contrast can be achieved at 3.0 T as compared with at 1.5 T. Adapting a 1.5-T protocol to the 3.0-T environment is subject to a variety of factors. In order to reduce the number of potential variables, we chose two cornerstones: the 3.0-T sequence should have similar spatial resolution and acquisition time; furthermore, the contrast parameters repetition time (TR) and echo time (TE) were kept identical. Based on this modified 3.0-T T2-weighted turbo spin-echo sequence (TR/TE 2,705/80 ms; 0.7 x 1.04 x 4 mm measured voxel size; field of view 360 mm; 4.03-min scan time) we performed an intraindividual study on 19 patients with the 1.5-T sequence as the standard of reference. Two radiologists analyzed the examinations in consensus with regard to tissue contrast (visualization of zonal anatomy of the uterus and/or delineation of pathologic findings) rated on a three-point scale (3 is 3.0 T better; 2 is 3.0 T equal; 1 is 3.0 T worse than 1.5 T). In addition, the signal difference between muscle and bone marrow was measured as a marker for tissue contrast. The analysis of the image quality comprised the level of the artifacts (rated on a five-point scale: 1 is no artifacts; 5 is nondiagnostic study), the visual signal-to-noise ratio (rated on a three-point scale) and detail delineation. Only minor artifacts were observed at both 1.5 and 3.0 T; the difference was not statistically significant. The visual signal-to-noise ratio and the delineation of image details were rated equal for 1.5 and 3.0 T. With regard to image contrast, both qualitative analysis as well as quantitative analysis revealed comparable image contrast for the 1.5- and 3.0-T protocols. Pathological findings were seen equally well with both field strengths. Clinically diagnostic pelvic studies of high image quality can be obtained using a 3.0-T scanner

  5. Analysis of gene expression levels in individual bacterial cells without image segmentation

    International Nuclear Information System (INIS)

    Kwak, In Hae; Son, Minjun; Hagen, Stephen J.

    2012-01-01

    Highlights: ► We present a method for extracting gene expression data from images of bacterial cells. ► The method does not employ cell segmentation and does not require high magnification. ► Fluorescence and phase contrast images of the cells are correlated through the physics of phase contrast. ► We demonstrate the method by characterizing noisy expression of comX in Streptococcus mutans. -- Abstract: Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly.

  6. Automated curved planar reformation of 3D spine images

    International Nuclear Information System (INIS)

    Vrtovec, Tomaz; Likar, Bostjan; Pernus, Franjo

    2005-01-01

    Traditional techniques for visualizing anatomical structures are based on planar cross-sections from volume images, such as images obtained by computed tomography (CT) or magnetic resonance imaging (MRI). However, planar cross-sections taken in the coordinate system of the 3D image often do not provide sufficient or qualitative enough diagnostic information, because planar cross-sections cannot follow curved anatomical structures (e.g. arteries, colon, spine, etc). Therefore, not all of the important details can be shown simultaneously in any planar cross-section. To overcome this problem, reformatted images in the coordinate system of the inspected structure must be created. This operation is usually referred to as curved planar reformation (CPR). In this paper we propose an automated method for CPR of 3D spine images, which is based on the image transformation from the standard image-based to a novel spine-based coordinate system. The axes of the proposed spine-based coordinate system are determined on the curve that represents the vertebral column, and the rotation of the vertebrae around the spine curve, both of which are described by polynomial models. The optimal polynomial parameters are obtained in an image analysis based optimization framework. The proposed method was qualitatively and quantitatively evaluated on five CT spine images. The method performed well on both normal and pathological cases and was consistent with manually obtained ground truth data. The proposed spine-based CPR benefits from reduced structural complexity in favour of improved feature perception of the spine. The reformatted images are diagnostically valuable and enable easier navigation, manipulation and orientation in 3D space. Moreover, reformatted images may prove useful for segmentation and other image analysis tasks

  7. Low-level contrast statistics of natural images can modulate the frequency of event-related potentials (ERP in humans

    Directory of Open Access Journals (Sweden)

    Masoud Ghodrati

    2016-12-01

    Full Text Available Humans are fast and accurate in categorizing complex natural images. It is, however, unclear what features of visual information are exploited by brain to perceive the images with such speed and accuracy. It has been shown that low-level contrast statistics of natural scenes can explain the variance of amplitude of event-related potentials (ERP in response to rapidly presented images. In this study, we investigated the effect of these statistics on frequency content of ERPs. We recorded ERPs from human subjects, while they viewed natural images each presented for 70 ms. Our results showed that Weibull contrast statistics, as a biologically plausible model, explained the variance of ERPs the best, compared to other image statistics that we assessed. Our time-frequency analysis revealed a significant correlation between these statistics and ERPs’ power within theta frequency band (~3-7 Hz. This is interesting, as theta band is believed to be involved in context updating and semantic encoding. This correlation became significant at ~110 ms after stimulus onset, and peaked at 138 ms. Our results show that not only the amplitude but also the frequency of neural responses can be modulated with low-level contrast statistics of natural images and highlights their potential role in scene perception.

  8. Dependence of the appearance-based perception of criminality, suggestibility, and trustworthiness on the level of pixelation of facial images.

    Science.gov (United States)

    Nurmoja, Merle; Eamets, Triin; Härma, Hanne-Loore; Bachmann, Talis

    2012-10-01

    While the dependence of face identification on the level of pixelation-transform of the images of faces has been well studied, similar research on face-based trait perception is underdeveloped. Because depiction formats used for hiding individual identity in visual media and evidential material recorded by surveillance cameras often consist of pixelized images, knowing the effects of pixelation on person perception has practical relevance. Here, the results of two experiments are presented showing the effect of facial image pixelation on the perception of criminality, trustworthiness, and suggestibility. It appears that individuals (N = 46, M age = 21.5 yr., SD = 3.1 for criminality ratings; N = 94, M age = 27.4 yr., SD = 10.1 for other ratings) have the ability to discriminate between facial cues ndicative of these perceived traits from the coarse level of image pixelation (10-12 pixels per face horizontally) and that the discriminability increases with a decrease in the coarseness of pixelation. Perceived criminality and trustworthiness appear to be better carried by the pixelized images than perceived suggestibility.

  9. Optical 3D watermark based digital image watermarking for telemedicine

    Science.gov (United States)

    Li, Xiao Wei; Kim, Seok Tae

    2013-12-01

    Region of interest (ROI) of a medical image is an area including important diagnostic information and must be stored without any distortion. This algorithm for application of watermarking technique for non-ROI of the medical image preserving ROI. The paper presents a 3D watermark based medical image watermarking scheme. In this paper, a 3D watermark object is first decomposed into 2D elemental image array (EIA) by a lenslet array, and then the 2D elemental image array data is embedded into the host image. The watermark extraction process is an inverse process of embedding. The extracted EIA through the computational integral imaging reconstruction (CIIR) technique, the 3D watermark can be reconstructed. Because the EIA is composed of a number of elemental images possesses their own perspectives of a 3D watermark object. Even though the embedded watermark data badly damaged, the 3D virtual watermark can be successfully reconstructed. Furthermore, using CAT with various rule number parameters, it is possible to get many channels for embedding. So our method can recover the weak point having only one transform plane in traditional watermarking methods. The effectiveness of the proposed watermarking scheme is demonstrated with the aid of experimental results.

  10. Simultaneous 3D–2D image registration and C-arm calibration: Application to endovascular image-guided interventions

    Energy Technology Data Exchange (ETDEWEB)

    Mitrović, Uroš [Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, Ljubljana 1000, Slovenia and Cosylab, Control System Laboratory, Teslova ulica 30, Ljubljana 1000 (Slovenia); Pernuš, Franjo [Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, Ljubljana 1000 (Slovenia); Likar, Boštjan; Špiclin, Žiga, E-mail: ziga.spiclin@fe.uni-lj.si [Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, Ljubljana 1000, Slovenia and Sensum, Computer Vision Systems, Tehnološki Park 21, Ljubljana 1000 (Slovenia)

    2015-11-15

    Purpose: Three-dimensional to two-dimensional (3D–2D) image registration is a key to fusion and simultaneous visualization of valuable information contained in 3D pre-interventional and 2D intra-interventional images with the final goal of image guidance of a procedure. In this paper, the authors focus on 3D–2D image registration within the context of intracranial endovascular image-guided interventions (EIGIs), where the 3D and 2D images are generally acquired with the same C-arm system. The accuracy and robustness of any 3D–2D registration method, to be used in a clinical setting, is influenced by (1) the method itself, (2) uncertainty of initial pose of the 3D image from which registration starts, (3) uncertainty of C-arm’s geometry and pose, and (4) the number of 2D intra-interventional images used for registration, which is generally one and at most two. The study of these influences requires rigorous and objective validation of any 3D–2D registration method against a highly accurate reference or “gold standard” registration, performed on clinical image datasets acquired in the context of the intervention. Methods: The registration process is split into two sequential, i.e., initial and final, registration stages. The initial stage is either machine-based or template matching. The latter aims to reduce possibly large in-plane translation errors by matching a projection of the 3D vessel model and 2D image. In the final registration stage, four state-of-the-art intrinsic image-based 3D–2D registration methods, which involve simultaneous refinement of rigid-body and C-arm parameters, are evaluated. For objective validation, the authors acquired an image database of 15 patients undergoing cerebral EIGI, for which accurate gold standard registrations were established by fiducial marker coregistration. Results: Based on target registration error, the obtained success rates of 3D to a single 2D image registration after initial machine-based and

  11. The findings and the role of axial CT imaging and 3D imaging of gastric lesion by spiral CT

    International Nuclear Information System (INIS)

    Lee, Dong Ho; Ko, Young Tae

    1996-01-01

    The purpose of this study is to assess the efficacy of axial CT imaging and 3D imaging by spiral CT in the detection and evaluation of gastric lesion. Seventy-seven patients with pathologically-proven gastric lesions underwent axial CT and 3D imaging by spiral CT. There were 49 cases of advanced gastric carcinoma(AGC), 21 of early gastric carcinoma (EGC), three of benign ulcers, three of leiomyomas, and one case of lymphoma. Spiral CT was performed with 3-mm collimation, 4.5mm/sec table feed, and 1-1.5-mm reconstruction interval after the ingestion of gas. 3D imaging was obtained using the SSD technique, and on analysis a grade was given(excellent, good, poor). Axial CT scan was performed with 5-mm collimation, 7mm/sec table feed, and 5-mm reconstruction interval after the ingestion of water. Among 49 cases of AGC, excellent 3D images were obtained in seven patients (14.3%), good 3D images in 30(61.2%), and poor 3D images in 12(24.5%). Among the 12 patients with poor images, the cancers were located at the pyloric antrum in eight cases, were AGC Borrmann type 4 in three cases, and EGC-mimicking lesion in one case. Using axial CT scan alone, Borrmann's classification based tumor morphology were accurately identified in 67.3% of cases, but using 3D imaging, the corresponding figure was 85.7%. In 33 cases receiving surgery, good correlation between axial CT scan and pathology occurred in 72.7% of T class, and 69.7% of N class. Among 21 cases of EGC, excellent 3D images were obtained in three patients (14.3%), good 3D images in 14 (66.7%), and poor 3D images in two (9.5%). The other two cases of EGC were not detected. By axial CT scan, no tumor was detected in four cases, and there were two doubtful cases. 3D images of three benign ulcers were excellent in one case and good in two. 3D images of three leiomyomas and one lymphoma were excellent. Combined axial CT imaging and 3D imaging by spiral CT has the potential to accurately diagnose gastric lesions other than AGC

  12. Impact of the Parameter Variation on the Image Blurring in 3 T Magnetic Resonance Imaging: A Phantom Study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Woo; Lee, Sang Hoon; Kim, Nam Kug; Cho, Kyung Sik; Lee, Jin Seong [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2013-04-15

    To evaluate the effects of the key imaging-parameter alterations on the four MR sequences in a phantom study. Magnetic resonance (MR) imaging was performed on a MR phantom with an 8-channel head coil by using a 3 T MR system. The images were obtained in the axial plane on four MR sequences [T1-weighted, T2-weighted, Proton-density, and 3 dimensional (3D) fast spin echo (FSE)] with controlled variations in the following key parameters: 1) echo train length (ETL), 2) repetition time (TR), and 3) echo time (TE). The image blurring was determined by the degree of the gradient angle; i.e., the blurring increased as the gradient angle decreases. The increasing ETL was observed to cause an increase in the image blurring on all pulse sequences with a statistical significance (p = 0.004) on the 3D FSE. Increasing the TR appeared to have no effect except a statistically significant decrease on the T1-weighted images (p = 0.011). Increasing TE showed no effect on the T1-weighted images (p = 0.932); however, it caused an increase of blurring on the proton density images (p = 0.016) as well as the T2-weighted images (p < 0.001), and a decrease on the 3D FSE (p = 0.001). To reduce the image blurring, short ETL and long TE for 3D FSE, long TR for T1-weighted images and short TE for proton-density and T2-weighted images should be applied.

  13. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera

    Directory of Open Access Journals (Sweden)

    Yufu Qu

    2018-01-01

    Full Text Available In order to reconstruct three-dimensional (3D structures from an image sequence captured by unmanned aerial vehicles’ camera (UAVs and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth–map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  14. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera.

    Science.gov (United States)

    Qu, Yufu; Huang, Jianyu; Zhang, Xuan

    2018-01-14

    In order to reconstruct three-dimensional (3D) structures from an image sequence captured by unmanned aerial vehicles' camera (UAVs) and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth-map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  15. Chemical composition and digestibility of some browse plant species collected from Algerian arid rangelands

    Energy Technology Data Exchange (ETDEWEB)

    Boufennara, S.; Lopez, S.; Boussebouna, H.; Bodas, R.; Bouazza, L.

    2012-11-01

    Many wild browse and bush species are undervalued mainly because of insufficient knowledge about their potential feeding value. The objective was to evaluate some nutritional attributes of various Algerian browse and shub species (Atriplex halimus, Artemisia campestris, Artemisia herba-alba, Astragalus gombiformis, Calobota saharae, Retama raetam, Stipagrostis pungens, Lygeum spartum and Stipa tenacissima). Chemical composition, phenols and tannins concentration, in vitro digestibility, in vitro gas production kinetics and in vitro bio-assay for assessment of tannins using buffered rumen fluid, and in situ disappearence of the edible parts of the plants (leaves, thin twigs and flowers) were determined. In general, protein content in dicotyledon species was always greater than in monocotyledon grasses, these showing higher neutral and acid detergent fibre and lower lignin contents than dicots. The tannin concentrations varied considerably between species, but in general the plants investigated in this study had low tannin contents (except for Artemisia spp. and S. tenacissima). Monocots showed lower in vitro and in situ digestibilities, fermentation rate, cumulative gas production and extent of degradation than dicot species. The plants were clustered by principal components analysis in two groups: poor-quality grasses and the most digestible dicot species. Chemical composition (neutral detergent fibre and protein) and digestibility were the main influential variables determining the ranking. In conclusion, A. halimus, A. campestris, A. herba-alba and A. gombiformis can be considered of greater nutritional value than the highly fibrous and low digestible grasses (S. pungens, L. spartum and S. tenacissima) that should be considered emergency roughages. (Author) 46 refs.

  16. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 100 of 109 ... Vol 4, No 1 (2004), HIV/AIDS Awareness Level of First Students of a ... Vol 3, No 1 (2003), Penile Cancer in North- Eastern Nigeria ... Vol 3, No 1 (2003), The Biochemical Composition of the Breast Milk of Nigerian Mothers.

  17. Pragmatic fully 3D image reconstruction for the MiCES mouse imaging PET scanner

    International Nuclear Information System (INIS)

    Lee, Kisung; Kinahan, Paul E; Fessler, Jeffrey A; Miyaoka, Robert S; Janes, Marie; Lewellen, Tom K

    2004-01-01

    We present a pragmatic approach to image reconstruction for data from the micro crystal elements system (MiCES) fully 3D mouse imaging positron emission tomography (PET) scanner under construction at the University of Washington. Our approach is modelled on fully 3D image reconstruction used in clinical PET scanners, which is based on Fourier rebinning (FORE) followed by 2D iterative image reconstruction using ordered-subsets expectation-maximization (OSEM). The use of iterative methods allows modelling of physical effects (e.g., statistical noise, detector blurring, attenuation, etc), while FORE accelerates the reconstruction process by reducing the fully 3D data to a stacked set of independent 2D sinograms. Previous investigations have indicated that non-stationary detector point-spread response effects, which are typically ignored for clinical imaging, significantly impact image quality for the MiCES scanner geometry. To model the effect of non-stationary detector blurring (DB) in the FORE+OSEM(DB) algorithm, we have added a factorized system matrix to the ASPIRE reconstruction library. Initial results indicate that the proposed approach produces an improvement in resolution without an undue increase in noise and without a significant increase in the computational burden. The impact on task performance, however, remains to be evaluated

  18. Guideline level-3 PSA

    International Nuclear Information System (INIS)

    Roelofsen, P.M.; Van der Steen, J.

    1993-09-01

    For several applications of radioactive materials calculations must be executed to determine the radiation risk for the population. A guideline for the risk calculation method of two main sources: nuclear power plants, and other intended and unintended activities with radioactive materials, is given. The standards, recommendations and regulations in this report concern mainly the analysis of the radiological (external) consequences of nuclear power plant accidents, classified as level-3 PSA (Probabilistic Safety Analysis). Level-3 PSA falls within the scales 5-7 of the International Nuclear Event Scale (INES). The standards, etc., focus on the risks for groups of people and the so-called maximum individual risk. In chapter two the standards and regulations are formulated for each part of level-3 PSA: the source term spectrum, atmospheric distribution and deposition, exposure to radiation doses and calculation of radiation doses, dose-response relationships, measures to reduce the effect of radiation doses, design basis accidents, and finally uncertainty analysis. In chapter four, modelled descriptions are given of the standards and regulations, which could or should be used in a calculation program in case of level-3 PSA. In chapter three the practical execution of a probabilistic consequences analysis, the collection of input data and the presentation of the results are dealt with. 2 figs., 14 tabs., 64 refs

  19. A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation.

    Science.gov (United States)

    Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

    2017-11-01

    Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi 3 + beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm 2 . The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

  20. A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation

    Science.gov (United States)

    Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

    2017-11-01

    Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi3+ beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm2. The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

  1. From medical imaging data to 3D printed anatomical models.

    Directory of Open Access Journals (Sweden)

    Thore M Bücking

    Full Text Available Anatomical models are important training and teaching tools in the clinical environment and are routinely used in medical imaging research. Advances in segmentation algorithms and increased availability of three-dimensional (3D printers have made it possible to create cost-efficient patient-specific models without expert knowledge. We introduce a general workflow that can be used to convert volumetric medical imaging data (as generated by Computer Tomography (CT to 3D printed physical models. This process is broken up into three steps: image segmentation, mesh refinement and 3D printing. To lower the barrier to entry and provide the best options when aiming to 3D print an anatomical model from medical images, we provide an overview of relevant free and open-source image segmentation tools as well as 3D printing technologies. We demonstrate the utility of this streamlined workflow by creating models of ribs, liver, and lung using a Fused Deposition Modelling 3D printer.

  2. MR imaging in epilepsy with use of 3D MP-RAGE

    International Nuclear Information System (INIS)

    Tanaka, Akio; Ohno, Sigeru; Sei, Tetsuro; Kanazawa, Susumu; Yasui, Koutaro; Kuroda, Masahiro; Hiraki, Yoshio; Oka, Eiji

    1996-01-01

    The patients were 40 males and 33 females; their ages ranged from 1 month to 39 years (mean: 15.7 years). The patients underwent MR imaging, including spin-echo T 1 -weighted, turbo spin-echo proton density/T 2 -weighted, and 3D magnetization-prepared rapid gradient-echo (3D MP-RAGE) images. These examinations disclosed 39 focal abnormalities. On visual evaluation, the boundary of abnormal gray matter in the neuronal migration disorder (NMD) cases was most clealy shown on 3D MP-RAGE images as compared to the other images. This is considered to be due to the higher spatial resolution and the better contrast of the 3D MP-RAGE images than those of the other techniques. The relative contrast difference between abnormal gray matter and the adjacent white matter was also assessed. The results revealed that the contrast differences on the 3D MP-RAGE images were larger than those on the other images; this was statistically significant. Although the sensitivity of 3D MP-RAGE for NMD was not specifically evaluated in this study, the possibility of this disorder, in cases suspected on other images, could be ruled out. Thus, it appears that the specificity with respect to NMD was at least increased with us of 3D MP-RAGE. 3D MP-RAGE also enabled us to build three-dimensional surface models that were helpful in understanding the three-dimensional anatomy. Furthermore. 3D MP-RAGE was considered to be the best technique for evaluating hippocampus atrophy in patients with MTS. On the other hand, the sensitivity in the signal change of the hippocampus was higher on T 2 -weighted images. In addition, demonstration of cortical tubers of tuberous sclerosis in neurocutaneous syndrome was superior on T 2 -weighted images than on 3D MP-RAGE images. (K.H.)

  3. Interaction between High-Level and Low-Level Image Analysis for Semantic Video Object Extraction

    Directory of Open Access Journals (Sweden)

    Andrea Cavallaro

    2004-06-01

    Full Text Available The task of extracting a semantic video object is split into two subproblems, namely, object segmentation and region segmentation. Object segmentation relies on a priori assumptions, whereas region segmentation is data-driven and can be solved in an automatic manner. These two subproblems are not mutually independent, and they can benefit from interactions with each other. In this paper, a framework for such interaction is formulated. This representation scheme based on region segmentation and semantic segmentation is compatible with the view that image analysis and scene understanding problems can be decomposed into low-level and high-level tasks. Low-level tasks pertain to region-oriented processing, whereas the high-level tasks are closely related to object-level processing. This approach emulates the human visual system: what one “sees” in a scene depends on the scene itself (region segmentation as well as on the cognitive task (semantic segmentation at hand. The higher-level segmentation results in a partition corresponding to semantic video objects. Semantic video objects do not usually have invariant physical properties and the definition depends on the application. Hence, the definition incorporates complex domain-specific knowledge and is not easy to generalize. For the specific implementation used in this paper, motion is used as a clue to semantic information. In this framework, an automatic algorithm is presented for computing the semantic partition based on color change detection. The change detection strategy is designed to be immune to the sensor noise and local illumination variations. The lower-level segmentation identifies the partition corresponding to perceptually uniform regions. These regions are derived by clustering in an N-dimensional feature space, composed of static as well as dynamic image attributes. We propose an interaction mechanism between the semantic and the region partitions which allows to

  4. Diagnosing and ranking retinopathy disease level using diabetic fundus image recuperation approach.

    Science.gov (United States)

    Somasundaram, K; Rajendran, P Alli

    2015-01-01

    Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED) and Optimally Adjusted Morphological Operator (OAMO) effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR) method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  5. AUTOMATED CELL SEGMENTATION WITH 3D FLUORESCENCE MICROSCOPY IMAGES.

    Science.gov (United States)

    Kong, Jun; Wang, Fusheng; Teodoro, George; Liang, Yanhui; Zhu, Yangyang; Tucker-Burden, Carol; Brat, Daniel J

    2015-04-01

    A large number of cell-oriented cancer investigations require an effective and reliable cell segmentation method on three dimensional (3D) fluorescence microscopic images for quantitative analysis of cell biological properties. In this paper, we present a fully automated cell segmentation method that can detect cells from 3D fluorescence microscopic images. Enlightened by fluorescence imaging techniques, we regulated the image gradient field by gradient vector flow (GVF) with interpolated and smoothed data volume, and grouped voxels based on gradient modes identified by tracking GVF field. Adaptive thresholding was then applied to voxels associated with the same gradient mode where voxel intensities were enhanced by a multiscale cell filter. We applied the method to a large volume of 3D fluorescence imaging data of human brain tumor cells with (1) small cell false detection and missing rates for individual cells; and (2) trivial over and under segmentation incidences for clustered cells. Additionally, the concordance of cell morphometry structure between automated and manual segmentation was encouraging. These results suggest a promising 3D cell segmentation method applicable to cancer studies.

  6. Browse Title Index

    African Journals Online (AJOL)

    Items 601 - 650 of 1329 ... Vol 20, No 3 (2016), Evaluation of the levels of phthalate ester plasticizers in surface water of Ethiope River System, Delta State, Nigeria, Abstract PDF. O Edjere, I.G. Asibor, S.E. Otolo. Vol 20, No 4 (2016), Evaluation of the levels of renal indices and blood pressure in Type 2 diabetes mellitus, ...

  7. Lossy/lossless coding of bi-level images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1997-01-01

    Summary form only given. We present improvements to a general type of lossless, lossy, and refinement coding of bi-level images (Martins and Forchhammer, 1996). Loss is introduced by flipping pixels. The pixels are coded using arithmetic coding of conditional probabilities obtained using a template...... as is known from JBIG and proposed in JBIG-2 (Martins and Forchhammer). Our new state-of-the-art results are obtained using the more general free tree instead of a template. Also we introduce multiple refinement template coding. The lossy algorithm is analogous to the greedy `rate...

  8. 3D quantitative phase imaging of neural networks using WDT

    Science.gov (United States)

    Kim, Taewoo; Liu, S. C.; Iyer, Raj; Gillette, Martha U.; Popescu, Gabriel

    2015-03-01

    White-light diffraction tomography (WDT) is a recently developed 3D imaging technique based on a quantitative phase imaging system called spatial light interference microscopy (SLIM). The technique has achieved a sub-micron resolution in all three directions with high sensitivity granted by the low-coherence of a white-light source. Demonstrations of the technique on single cell imaging have been presented previously; however, imaging on any larger sample, including a cluster of cells, has not been demonstrated using the technique. Neurons in an animal body form a highly complex and spatially organized 3D structure, which can be characterized by neuronal networks or circuits. Currently, the most common method of studying the 3D structure of neuron networks is by using a confocal fluorescence microscope, which requires fluorescence tagging with either transient membrane dyes or after fixation of the cells. Therefore, studies on neurons are often limited to samples that are chemically treated and/or dead. WDT presents a solution for imaging live neuron networks with a high spatial and temporal resolution, because it is a 3D imaging method that is label-free and non-invasive. Using this method, a mouse or rat hippocampal neuron culture and a mouse dorsal root ganglion (DRG) neuron culture have been imaged in order to see the extension of processes between the cells in 3D. Furthermore, the tomogram is compared with a confocal fluorescence image in order to investigate the 3D structure at synapses.

  9. Image acquisition and planimetry systems to develop wounding techniques in 3D wound model

    Directory of Open Access Journals (Sweden)

    Kiefer Ann-Kathrin

    2017-09-01

    Full Text Available Wound healing represents a complex biological repair process. Established 2D monolayers and wounding techniques investigate cell migration, but do not represent coordinated multi-cellular systems. We aim to use wound surface area measurements obtained from image acquisition and planimetry systems to establish our wounding technique and in vitro organotypic tissue. These systems will be used in our future wound healing treatment studies to assess the rate of wound closure in response to wound healing treatment with light therapy (photobiomodulation. The image acquisition and planimetry systems were developed, calibrated, and verified to measure wound surface area in vitro. The system consists of a recording system (Sony DSC HX60, 20.4 M Pixel, 1/2.3″ CMOS sensor and calibrated with 1mm scale paper. Macro photography with an optical zoom magnification of 2:1 achieves sufficient resolution to evaluate the 3mm wound size and healing growth. The camera system was leveled with an aluminum construction to ensure constant distance and orientation of the images. The JPG-format images were processed with a planimetry system in MATLAB. Edge detection enables definition of the wounded area. Wound area can be calculated with surface integrals. To separate the wounded area from the background, the image was filtered in several steps. Agar models, injured through several test persons with different levels of experience, were used as pilot data to test the planimetry software. These image acquisition and planimetry systems support the development of our wound healing research. The reproducibility of our wounding technique can be assessed by the variability in initial wound surface area. Also, wound healing treatment effects can be assessed by the change in rate of wound closure. These techniques represent the foundations of our wound model, wounding technique, and analysis systems in our ongoing studies in wound healing and therapy.

  10. Analysis of gene expression levels in individual bacterial cells without image segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, In Hae; Son, Minjun [Physics Department, University of Florida, P.O. Box 118440, Gainesville, FL 32611-8440 (United States); Hagen, Stephen J., E-mail: sjhagen@ufl.edu [Physics Department, University of Florida, P.O. Box 118440, Gainesville, FL 32611-8440 (United States)

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer We present a method for extracting gene expression data from images of bacterial cells. Black-Right-Pointing-Pointer The method does not employ cell segmentation and does not require high magnification. Black-Right-Pointing-Pointer Fluorescence and phase contrast images of the cells are correlated through the physics of phase contrast. Black-Right-Pointing-Pointer We demonstrate the method by characterizing noisy expression of comX in Streptococcus mutans. -- Abstract: Studies of stochasticity in gene expression typically make use of fluorescent protein reporters, which permit the measurement of expression levels within individual cells by fluorescence microscopy. Analysis of such microscopy images is almost invariably based on a segmentation algorithm, where the image of a cell or cluster is analyzed mathematically to delineate individual cell boundaries. However segmentation can be ineffective for studying bacterial cells or clusters, especially at lower magnification, where outlines of individual cells are poorly resolved. Here we demonstrate an alternative method for analyzing such images without segmentation. The method employs a comparison between the pixel brightness in phase contrast vs fluorescence microscopy images. By fitting the correlation between phase contrast and fluorescence intensity to a physical model, we obtain well-defined estimates for the different levels of gene expression that are present in the cell or cluster. The method reveals the boundaries of the individual cells, even if the source images lack the resolution to show these boundaries clearly.

  11. Reducing surgical levels by paraspinal mapping and diffusion tensor imaging techniques in lumbar spinal stenosis

    OpenAIRE

    Chen, Hua-Biao; Wan, Qi; Xu, Qi-Feng; Chen, Yi; Bai, Bo

    2016-01-01

    Background Correlating symptoms and physical examination findings with surgical levels based on common imaging results is not reliable. In patients who have no concordance between radiological and clinical symptoms, the surgical levels determined by conventional magnetic resonance imaging (MRI) and neurogenic examination (NE) may lead to a more extensive surgery and significant complications. We aimed to confirm that whether the use of diffusion tensor imaging (DTI) and paraspinal mapping (PM...

  12. Monitoring the fibrolytic potential of microbial ecosystems from domestic and wild ruminants browsing tanniferous forages

    Directory of Open Access Journals (Sweden)

    Nokwethemba Nqobile Philile Msimango

    2016-03-01

    Full Text Available Although the rumen microbiome has been reported to synthesize a rich source of symbiotic enzymes (exocellulase, endocellulase, hemicellulase and cellobiase, the digestion of tropical C4 grasses and browses by ruminants is still limited. Therefore, this study aimed to unveil potential fibrolytic microbial ecosystems from giraffe, kudu, impala and consortia (A1 [giraffe + kudu], A2 [giraffe + impala], A3 [kudu + impala], and A4 [giraffe + kudu + impala] browsing tanniferous plants, which can be used to improve forage utilization in domesticated goat. Crude protein enzyme extracts (CPZ from fresh faecal samples were precipitated by 60% ammonium sulphate and assayed for exocellulase, endocellulase and hemicellulase by incubating with crystalline cellulose, carboxymethyl cellulose and xylan at 38 °C with optimum pH of 5.5 to 6.5 for 1, 2, and 48 h, respectively. Enzyme specific activities were defined as μg of reducing sugar/mg CPZ. In vitro fermentation study was done by transferring 33 mL of fresh faecal inoculum into 67 mL of salivary buffer containing 1 g Acacia sieberiana and incubating for 72 h at 38 °C. Apparent degradability (APDeg, true degradability (TD, neutral detergent fibre degradability (NDFdeg, acid detergent fibre degradability (ADFdeg, microbial yield (MY, metabolizable energy (ME and total gas emitted (Gas were measured. Exocellulase activities were higher (P < 0.05 in all wild animals and consortia than those in goat except for A4. Minimal differences in hemicellulase activities (P < 0.05 were observed among goat and wild animals and consortia, while endocellulase activity was generally higher (P < 0.05 in goat than that in the rest of the systems. Apart from A3, TDeg, NDFdeg and ADFdeg were higher (P < 0.05 in all microbial ecosystems from wild animals and consortia than those in goat. Apparent degradability, MY and ME also varied (P < 0.05 among these systems. Giraffe, Kudu and A3 produced lower (P

  13. Species composition, elevation, and former management type affect browsing pressure on forest regeneration in the Tatra National Park

    Directory of Open Access Journals (Sweden)

    Bodziarczyk Jan

    2017-06-01

    Full Text Available Effects of ungulate pressure on the development of young generation of trees is one of the most important issues in ecology and forestry. Ungulate pressure influence on the development of natural regeneration has been also reported from several national parks. Our study on the effects of ungulate browsing on the young generation of trees was conducted on more than 500 sample plots controlled during one growing season.

  14. High-resolution MR imaging of the knee at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, M.; Nakai, T.; Ikeda, K.; Tang, G.Y.; Yoshioka, H.; Itai, Y. [Tsukuba Univ., Ibaraki (Japan). Dept. of Radiology

    2000-07-01

    In order to examine the practical feasibility of using a 3.0-T MR unit to obtain high-quality, high-resolution images of the knee joint, one human cadaveric and 5 porcine knees were imaged with the 3.0-T unit. Sets of T1-weighted spin echo images were obtained with in-plane resolution of 0.195x0.39 mm and an acquisition time of approximately 5 min. Two porcine knees were also imaged with the 1.0-T unit with an identical imaging protocol and the signal-to-noise (S/N) ratios were measured on images at 3 T and 1 T. The 3-T MR system provided detailed delineation of the knees. Deep layers of the medial collateral ligament and associated fine fibers beneath the medial and lateral collateral ligament were demarcated. We observed precise demonstration of the tibial attachment of the anterior cruciate ligament, irregularity of the meniscal free edge, and conjoint tendon formation together with the lateral collateral ligament and the biceps femoris tendon. Compared to the 1-T unit, the S/N ratio with the 3-T unit was increased by a factor of 1.39 to 1.72. Due to the potential advantage of obtaining detailed images, the 3-T MR system suggests a practical utility for fine demonstration of the knee morphology.

  15. High-resolution MR imaging of the knee at 3 T

    International Nuclear Information System (INIS)

    Niitsu, M.; Nakai, T.; Ikeda, K.; Tang, G.Y.; Yoshioka, H.; Itai, Y.

    2000-01-01

    In order to examine the practical feasibility of using a 3.0-T MR unit to obtain high-quality, high-resolution images of the knee joint, one human cadaveric and 5 porcine knees were imaged with the 3.0-T unit. Sets of T1-weighted spin echo images were obtained with in-plane resolution of 0.195x0.39 mm and an acquisition time of approximately 5 min. Two porcine knees were also imaged with the 1.0-T unit with an identical imaging protocol and the signal-to-noise (S/N) ratios were measured on images at 3 T and 1 T. The 3-T MR system provided detailed delineation of the knees. Deep layers of the medial collateral ligament and associated fine fibers beneath the medial and lateral collateral ligament were demarcated. We observed precise demonstration of the tibial attachment of the anterior cruciate ligament, irregularity of the meniscal free edge, and conjoint tendon formation together with the lateral collateral ligament and the biceps femoris tendon. Compared to the 1-T unit, the S/N ratio with the 3-T unit was increased by a factor of 1.39 to 1.72. Due to the potential advantage of obtaining detailed images, the 3-T MR system suggests a practical utility for fine demonstration of the knee morphology

  16. Automated tracking of lava lake level using thermal images at Kīlauea Volcano, Hawai’i

    Science.gov (United States)

    Patrick, Matthew R.; Swanson, Don; Orr, Tim R.

    2016-01-01

    Tracking the level of the lava lake in Halema‘uma‘u Crater, at the summit of Kīlauea Volcano, Hawai’i, is an essential part of monitoring the ongoing eruption and forecasting potentially hazardous changes in activity. We describe a simple automated image processing routine that analyzes continuously-acquired thermal images of the lava lake and measures lava level. The method uses three image segmentation approaches, based on edge detection, short-term change analysis, and composite temperature thresholding, to identify and track the lake margin in the images. These relative measurements from the images are periodically calibrated with laser rangefinder measurements to produce real-time estimates of lake elevation. Continuous, automated tracking of the lava level has been an important tool used by the U.S. Geological Survey’s Hawaiian Volcano Observatory since 2012 in real-time operational monitoring of the volcano and its hazard potential.

  17. The value of 3D T1-weighted gradient-echo MR imaging for evaluation of the appendix during pregnancy: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kyung Mi; Kim, Seong Hyun; Choi, Dongil; Lee, Soon Jin; Rhim, Hyunchul; Park, Min Jung (Depts. of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of)), email: kshyun@skku.edu

    2011-10-15

    Background The use of oral contrast has been essential for the identification of a normal appendix on MR imaging during pregnancy. However, stool could be used as a positive oral contrast as it is characterized by a relatively high signal on T1-weighted imaging, and 3D T1-weighted gradient-echo (T1W-GRE) MR imaging has been used to evaluate 3 mm diameter intestines in fetuses. Purpose To evaluate the added value of 3D T1W-GRE MR imaging in combination with T2-weighted imaging (T2WI) compared to T2WI alone for evaluating the appendix during pregnancy. Material and Methods Eighteen consecutive pregnant patients who were clinically suspected of having acute appendicitis underwent appendix MR imaging which included T2WI with or without spectral presaturation attenuated inversion-recovery (SPAIR) fat suppression, and 3D T1W-GRE with SPAIR fat suppression. Two radiologists reviewed the two image sets (the T2WI set and the combined set of T2WI and 3D T1W-GRE images). Pathologic and clinical results served as the reference standard. The differences in the degree of visibility of the appendix and confidence scale for diagnosing acute appendicitis between two image sets were compared by using the paired Wilcoxon signed rank test. Results For both reviewers, the degree of visibility of the appendix using the combined T2WI and 3D T1W-GRE images was significantly higher than using T2WI alone (P < 0.01), and the confidence levels for acute appendicitis using combined T2WI and 3D T1W-GRE images were significantly different from those using T2WI alone (P < 0.01). In the 13 patients with a normal appendix, both reviewers showed improved confidence levels for appendicitis using combined T2WI and 3D T1W-GRE images than T2WI alone. Conclusion Adding 3D T1W-GRE images to T2WI is helpful for identification of the appendix, as compared to T2WI alone in pregnant women without ingestion of oral contrast material. This may improve diagnostic confidence for acute appendicitis in pregnant

  18. 3D Printing Openable Imaging Phantom Design

    International Nuclear Information System (INIS)

    Kim, Myoung Keun; Won, Jun Hyeok; Lee, Seung Wook

    2017-01-01

    The purpose of this study is to design an openable phantom that can replace the internal measurement bar used for contrast comparison in order to increase the efficiency of manufacturing imaging phantom used in the medical industry and to improve convenience using 3D printer. Phantom concept design, 3D printing, and Image reconstruction were defined as the scope of the thesis. Also, we study metal artifact reduction with openable phantom. We have designed a Openable phantom using 3D printing, and have investigated metal artifact reduction after inserting a metallic material inside the phantom. The openable phantom can be adjusted at any time to suit the user's experiment and can be easily replaced and useful.

  19. 3D Point Cloud Reconstruction from Single Plenoptic Image

    Directory of Open Access Journals (Sweden)

    F. Murgia

    2016-06-01

    Full Text Available Novel plenoptic cameras sample the light field crossing the main camera lens. The information available in a plenoptic image must be processed, in order to create the depth map of the scene from a single camera shot. In this paper a novel algorithm, for the reconstruction of 3D point cloud of the scene from a single plenoptic image, taken with a consumer plenoptic camera, is proposed. Experimental analysis is conducted on several test images, and results are compared with state of the art methodologies. The results are very promising, as the quality of the 3D point cloud from plenoptic image, is comparable with the quality obtained with current non-plenoptic methodologies, that necessitate more than one image.

  20. Quantitative Image Feature Engine (QIFE): an Open-Source, Modular Engine for 3D Quantitative Feature Extraction from Volumetric Medical Images.

    Science.gov (United States)

    Echegaray, Sebastian; Bakr, Shaimaa; Rubin, Daniel L; Napel, Sandy

    2017-10-06

    The aim of this study was to develop an open-source, modular, locally run or server-based system for 3D radiomics feature computation that can be used on any computer system and included in existing workflows for understanding associations and building predictive models between image features and clinical data, such as survival. The QIFE exploits various levels of parallelization for use on multiprocessor systems. It consists of a managing framework and four stages: input, pre-processing, feature computation, and output. Each stage contains one or more swappable components, allowing run-time customization. We benchmarked the engine using various levels of parallelization on a cohort of CT scans presenting 108 lung tumors. Two versions of the QIFE have been released: (1) the open-source MATLAB code posted to Github, (2) a compiled version loaded in a Docker container, posted to DockerHub, which can be easily deployed on any computer. The QIFE processed 108 objects (tumors) in 2:12 (h/mm) using 1 core, and 1:04 (h/mm) hours using four cores with object-level parallelization. We developed the Quantitative Image Feature Engine (QIFE), an open-source feature-extraction framework that focuses on modularity, standards, parallelism, provenance, and integration. Researchers can easily integrate it with their existing segmentation and imaging workflows by creating input and output components that implement their existing interfaces. Computational efficiency can be improved by parallelizing execution at the cost of memory usage. Different parallelization levels provide different trade-offs, and the optimal setting will depend on the size and composition of the dataset to be processed.

  1. 4D reconstruction of the past: the image retrieval and 3D model construction pipeline

    Science.gov (United States)

    Hadjiprocopis, Andreas; Ioannides, Marinos; Wenzel, Konrad; Rothermel, Mathias; Johnsons, Paul S.; Fritsch, Dieter; Doulamis, Anastasios; Protopapadakis, Eftychios; Kyriakaki, Georgia; Makantasis, Kostas; Weinlinger, Guenther; Klein, Michael; Fellner, Dieter; Stork, Andre; Santos, Pedro

    2014-08-01

    One of the main characteristics of the Internet era we are living in, is the free and online availability of a huge amount of data. This data is of varied reliability and accuracy and exists in various forms and formats. Often, it is cross-referenced and linked to other data, forming a nexus of text, images, animation and audio enabled by hypertext and, recently, by the Web3.0 standard. Our main goal is to enable historians, architects, archaeolo- gists, urban planners and affiliated professionals to reconstruct views of historical monuments from thousands of images floating around the web. This paper aims to provide an update of our progress in designing and imple- menting a pipeline for searching, filtering and retrieving photographs from Open Access Image Repositories and social media sites and using these images to build accurate 3D models of archaeological monuments as well as enriching multimedia of cultural / archaeological interest with metadata and harvesting the end products to EU- ROPEANA. We provide details of how our implemented software searches and retrieves images of archaeological sites from Flickr and Picasa repositories as well as strategies on how to filter the results, on two levels; a) based on their built-in metadata including geo-location information and b) based on image processing and clustering techniques. We also describe our implementation of a Structure from Motion pipeline designed for producing 3D models using the large collection of 2D input images (>1000) retrieved from Internet Repositories.

  2. 3D IMAGING USING COHERENT SYNCHROTRON RADIATION

    Directory of Open Access Journals (Sweden)

    Peter Cloetens

    2011-05-01

    Full Text Available Three dimensional imaging is becoming a standard tool for medical, scientific and industrial applications. The use of modem synchrotron radiation sources for monochromatic beam micro-tomography provides several new features. Along with enhanced signal-to-noise ratio and improved spatial resolution, these include the possibility of quantitative measurements, the easy incorporation of special sample environment devices for in-situ experiments, and a simple implementation of phase imaging. These 3D approaches overcome some of the limitations of 2D measurements. They require new tools for image analysis.

  3. Variational Level Set Method for Two-Stage Image Segmentation Based on Morphological Gradients

    Directory of Open Access Journals (Sweden)

    Zemin Ren

    2014-01-01

    Full Text Available We use variational level set method and transition region extraction techniques to achieve image segmentation task. The proposed scheme is done by two steps. We first develop a novel algorithm to extract transition region based on the morphological gradient. After this, we integrate the transition region into a variational level set framework and develop a novel geometric active contour model, which include an external energy based on transition region and fractional order edge indicator function. The external energy is used to drive the zero level set toward the desired image features, such as object boundaries. Due to this external energy, the proposed model allows for more flexible initialization. The fractional order edge indicator function is incorporated into the length regularization term to diminish the influence of noise. Moreover, internal energy is added into the proposed model to penalize the deviation of the level set function from a signed distance function. The results evolution of the level set function is the gradient flow that minimizes the overall energy functional. The proposed model has been applied to both synthetic and real images with promising results.

  4. Image-Based 3D Face Modeling System

    Directory of Open Access Journals (Sweden)

    Vladimir Vezhnevets

    2005-08-01

    Full Text Available This paper describes an automatic system for 3D face modeling using frontal and profile images taken by an ordinary digital camera. The system consists of four subsystems including frontal feature detection, profile feature detection, shape deformation, and texture generation modules. The frontal and profile feature detection modules automatically extract the facial parts such as the eye, nose, mouth, and ear. The shape deformation module utilizes the detected features to deform the generic head mesh model such that the deformed model coincides with the detected features. A texture is created by combining the facial textures augmented from the input images and the synthesized texture and mapped onto the deformed generic head model. This paper provides a practical system for 3D face modeling, which is highly automated by aggregating, customizing, and optimizing a bunch of individual computer vision algorithms. The experimental results show a highly automated process of modeling, which is sufficiently robust to various imaging conditions. The whole model creation including all the optional manual corrections takes only 2∼3 minutes.

  5. 3D ultrasound imaging : Fast and cost-effective morphometry of musculoskeletal tissue

    NARCIS (Netherlands)

    Weide, Guido; Van Der Zwaard, Stephan; Huijing, Peter A.; Jaspers, Richard T.; Harlaar, Jaap

    2017-01-01

    The developmental goal of 3D ultrasound imaging (3DUS) is to engineer a modality to perform 3D morphological ultrasound analysis of human muscles. 3DUS images are constructed from calibrated freehand 2D B-mode ultrasound images, which are positioned into a voxel array. Ultrasound (US) imaging allows

  6. Development of 3-D Medical Image VIsualization System

    African Journals Online (AJOL)

    User

    uses standard 2-D medical imaging inputs and generates medical images of human body parts ... light wave from points on the 3-D object(s) in ... tools, and communication bandwidth cannot .... locations along the track that correspond with.

  7. Automatic Generation of Building Models with Levels of Detail 1-3

    Science.gov (United States)

    Nguatem, W.; Drauschke, M.; Mayer, H.

    2016-06-01

    We present a workflow for the automatic generation of building models with levels of detail (LOD) 1 to 3 according to the CityGML standard (Gröger et al., 2012). We start with orienting unsorted image sets employing (Mayer et al., 2012), we compute depth maps using semi-global matching (SGM) (Hirschmüller, 2008), and fuse these depth maps to reconstruct dense 3D point clouds (Kuhn et al., 2014). Based on planes segmented from these point clouds, we have developed a stochastic method for roof model selection (Nguatem et al., 2013) and window model selection (Nguatem et al., 2014). We demonstrate our workflow up to the export into CityGML.

  8. SOFTWARE FOR REGIONS OF INTEREST RETRIEVAL ON MEDICAL 3D IMAGES

    Directory of Open Access Journals (Sweden)

    G. G. Stromov

    2014-01-01

    Full Text Available Background. Implementation of software for areas of interest retrieval in 3D medical images is described in this article. It has been tested against large volume of model MRIs.Material and methods. We tested software against normal and pathological (severe multiple sclerosis model MRIs from tge BrainWeb resource. Technological stack is based on open-source cross-platform solutions. We implemented storage system on Maria DB (an open-sourced fork of MySQL with P/SQL extensions. Python 2.7 scripting was used for automatization of extract-transform-load operations. The computational core is written on Java 7 with Spring framework 3. MongoDB was used as a cache in the cluster of workstations. Maven 3 was chosen as a dependency manager and build system, the project is hosted at Github.Results. As testing on SSMU's LAN has showed, software has been developed is quite efficiently retrieves ROIs are matching for the morphological substratum on pathological MRIs.Conclusion. Automation of a diagnostic process using medical imaging allows to level down the subjective component in decision making and increase the availability of hi-tech medicine. Software has shown in the article is a complex solution for ROI retrieving and segmentation process on model medical images in full-automated mode.We would like to thank Robert Vincent for great help with consulting of usage the BrainWeb resource.

  9. Integrated optical 3D digital imaging based on DSP scheme

    Science.gov (United States)

    Wang, Xiaodong; Peng, Xiang; Gao, Bruce Z.

    2008-03-01

    We present a scheme of integrated optical 3-D digital imaging (IO3DI) based on digital signal processor (DSP), which can acquire range images independently without PC support. This scheme is based on a parallel hardware structure with aid of DSP and field programmable gate array (FPGA) to realize 3-D imaging. In this integrated scheme of 3-D imaging, the phase measurement profilometry is adopted. To realize the pipeline processing of the fringe projection, image acquisition and fringe pattern analysis, we present a multi-threads application program that is developed under the environment of DSP/BIOS RTOS (real-time operating system). Since RTOS provides a preemptive kernel and powerful configuration tool, with which we are able to achieve a real-time scheduling and synchronization. To accelerate automatic fringe analysis and phase unwrapping, we make use of the technique of software optimization. The proposed scheme can reach a performance of 39.5 f/s (frames per second), so it may well fit into real-time fringe-pattern analysis and can implement fast 3-D imaging. Experiment results are also presented to show the validity of proposed scheme.

  10. 3D FaceCam: a fast and accurate 3D facial imaging device for biometrics applications

    Science.gov (United States)

    Geng, Jason; Zhuang, Ping; May, Patrick; Yi, Steven; Tunnell, David

    2004-08-01

    Human faces are fundamentally three-dimensional (3D) objects, and each face has its unique 3D geometric profile. The 3D geometric features of a human face can be used, together with its 2D texture, for rapid and accurate face recognition purposes. Due to the lack of low-cost and robust 3D sensors and effective 3D facial recognition (FR) algorithms, almost all existing FR systems use 2D face images. Genex has developed 3D solutions that overcome the inherent problems in 2D while also addressing limitations in other 3D alternatives. One important aspect of our solution is a unique 3D camera (the 3D FaceCam) that combines multiple imaging sensors within a single compact device to provide instantaneous, ear-to-ear coverage of a human face. This 3D camera uses three high-resolution CCD sensors and a color encoded pattern projection system. The RGB color information from each pixel is used to compute the range data and generate an accurate 3D surface map. The imaging system uses no moving parts and combines multiple 3D views to provide detailed and complete 3D coverage of the entire face. Images are captured within a fraction of a second and full-frame 3D data is produced within a few seconds. This described method provides much better data coverage and accuracy in feature areas with sharp features or details (such as the nose and eyes). Using this 3D data, we have been able to demonstrate that a 3D approach can significantly improve the performance of facial recognition. We have conducted tests in which we have varied the lighting conditions and angle of image acquisition in the "field." These tests have shown that the matching results are significantly improved when enrolling a 3D image rather than a single 2D image. With its 3D solutions, Genex is working toward unlocking the promise of powerful 3D FR and transferring FR from a lab technology into a real-world biometric solution.

  11. An automated 3D reconstruction method of UAV images

    Science.gov (United States)

    Liu, Jun; Wang, He; Liu, Xiaoyang; Li, Feng; Sun, Guangtong; Song, Ping

    2015-10-01

    In this paper a novel fully automated 3D reconstruction approach based on low-altitude unmanned aerial vehicle system (UAVs) images will be presented, which does not require previous camera calibration or any other external prior knowledge. Dense 3D point clouds are generated by integrating orderly feature extraction, image matching, structure from motion (SfM) and multi-view stereo (MVS) algorithms, overcoming many of the cost, time limitations of rigorous photogrammetry techniques. An image topology analysis strategy is introduced to speed up large scene reconstruction by taking advantage of the flight-control data acquired by UAV. Image topology map can significantly reduce the running time of feature matching by limiting the combination of images. A high-resolution digital surface model of the study area is produced base on UAV point clouds by constructing the triangular irregular network. Experimental results show that the proposed approach is robust and feasible for automatic 3D reconstruction of low-altitude UAV images, and has great potential for the acquisition of spatial information at large scales mapping, especially suitable for rapid response and precise modelling in disaster emergency.

  12. Diagnosing and Ranking Retinopathy Disease Level Using Diabetic Fundus Image Recuperation Approach

    Directory of Open Access Journals (Sweden)

    K. Somasundaram

    2015-01-01

    Full Text Available Retinal fundus images are widely used in diagnosing different types of eye diseases. The existing methods such as Feature Based Macular Edema Detection (FMED and Optimally Adjusted Morphological Operator (OAMO effectively detected the presence of exudation in fundus images and identified the true positive ratio of exudates detection, respectively. These mechanically detected exudates did not include more detailed feature selection technique to the system for detection of diabetic retinopathy. To categorize the exudates, Diabetic Fundus Image Recuperation (DFIR method based on sliding window approach is developed in this work to select the features of optic cup in digital retinal fundus images. The DFIR feature selection uses collection of sliding windows with varying range to obtain the features based on the histogram value using Group Sparsity Nonoverlapping Function. Using support vector model in the second phase, the DFIR method based on Spiral Basis Function effectively ranks the diabetic retinopathy disease level. The ranking of disease level on each candidate set provides a much promising result for developing practically automated and assisted diabetic retinopathy diagnosis system. Experimental work on digital fundus images using the DFIR method performs research on the factors such as sensitivity, ranking efficiency, and feature selection time.

  13. Hands-on guide for 3D image creation for geological purposes

    Science.gov (United States)

    Frehner, Marcel; Tisato, Nicola

    2013-04-01

    Geological structures in outcrops or hand specimens are inherently three dimensional (3D), and therefore better understandable if viewed in 3D. While 3D models can easily be created, manipulated, and looked at from all sides on the computer screen (e.g., using photogrammetry or laser scanning data), 3D visualizations for publications or conference posters are much more challenging as they have to live in a 2D-world (i.e., on a sheet of paper). Perspective 2D visualizations of 3D models do not fully transmit the "feeling and depth of the third dimension" to the audience; but this feeling is desirable for a better examination and understanding in 3D of the structure under consideration. One of the very few possibilities to generate real 3D images, which work on a 2D display, is by using so-called stereoscopic images. Stereoscopic images are two images of the same object recorded from two slightly offset viewpoints. Special glasses and techniques have to be used to make sure that one image is seen only by one eye, and the other image is seen by the other eye, which together lead to the "3D effect". Geoscientists are often familiar with such 3D images. For example, geomorphologists traditionally view stereographic orthophotos by employing a mirror-steroscope. Nowadays, petroleum-geoscientists examine high-resolution 3D seismic data sets in special 3D visualization rooms. One of the methods for generating and viewing a stereoscopic image, which does not require a high-tech viewing device, is to create a so-called anaglyph. The principle is to overlay two images saturated in red and cyan, respectively. The two images are then viewed through red-cyan-stereoscopic glasses. This method is simple and cost-effective, but has some drawbacks in preserving colors accurately. A similar method is used in 3D movies, where polarized light or shuttering techniques are used to separate the left from the right image, which allows preserving the original colors. The advantage of red

  14. An improved level set method for brain MR images segmentation and bias correction.

    Science.gov (United States)

    Chen, Yunjie; Zhang, Jianwei; Macione, Jim

    2009-10-01

    Intensity inhomogeneities cause considerable difficulty in the quantitative analysis of magnetic resonance (MR) images. Thus, bias field estimation is a necessary step before quantitative analysis of MR data can be undertaken. This paper presents a variational level set approach to bias correction and segmentation for images with intensity inhomogeneities. Our method is based on an observation that intensities in a relatively small local region are separable, despite of the inseparability of the intensities in the whole image caused by the overall intensity inhomogeneity. We first define a localized K-means-type clustering objective function for image intensities in a neighborhood around each point. The cluster centers in this objective function have a multiplicative factor that estimates the bias within the neighborhood. The objective function is then integrated over the entire domain to define the data term into the level set framework. Our method is able to capture bias of quite general profiles. Moreover, it is robust to initialization, and thereby allows fully automated applications. The proposed method has been used for images of various modalities with promising results.

  15. JPEG2000 and dissemination of cultural heritage over the Internet.

    Science.gov (United States)

    Politou, Eugenia A; Pavlidis, George P; Chamzas, Christodoulos

    2004-03-01

    By applying the latest technologies in image compression for managing the storage of massive image data within cultural heritage databases and by exploiting the universality of the Internet we are now able not only to effectively digitize, record and preserve, but also to promote the dissemination of cultural heritage. In this work we present an application of the latest image compression standard JPEG2000 in managing and browsing image databases, focusing on the image transmission aspect rather than database management and indexing. We combine the technologies of JPEG2000 image compression with client-server socket connections and client browser plug-in, as to provide with an all-in-one package for remote browsing of JPEG2000 compressed image databases, suitable for the effective dissemination of cultural heritage.

  16. High-Resolution 3T MR Imaging of the Triangular Fibrocartilage Complex.

    Science.gov (United States)

    von Borstel, Donald; Wang, Michael; Small, Kirstin; Nozaki, Taiki; Yoshioka, Hiroshi

    2017-01-10

    This study is intended as a review of 3Tesla (T) magnetic resonance (MR) imaging of the triangular fibrocartilage complex (TFCC). The recent advances in MR imaging, which includes high field strength magnets, multi-channel coils, and isotropic 3-dimensional (3D) sequences have enabled the visualization of precise TFCC anatomy with high spatial and contrast resolution. In addition to the routine wrist protocol, there are specific techniques used to optimize 3T imaging of the wrist; including driven equilibrium sequence (DRIVE), parallel imaging, and 3D imaging. The coil choice for 3T imaging of the wrist depends on a number of variables, and the proper coil design selection is critical for high-resolution wrist imaging with high signal and contrast-to-noise ratio. The TFCC is a complex structure and is composed of the articular disc (disc proper), the triangular ligament, the dorsal and volar radioulnar ligaments, the meniscus homologue, the ulnar collateral ligament (UCL), the extensor carpi ulnaris (ECU) tendon sheath, and the ulnolunate and ulnotriquetral ligaments. The Palmer classification categorizes TFCC lesions as traumatic (type 1) or degenerative (type 2). In this review article, we present clinical high-resolution MR images of normal TFCC anatomy and TFCC injuries with this classification system.

  17. Hand Vein Images Enhancement Based on Local Gray-level Information Histogram

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2015-06-01

    Full Text Available Based on the Histogram equalization theory, this paper presents a novel concept of histogram to realize the contrast enhancement of hand vein images, avoiding the lost of topological vein structure or importing the fake vein information. Firstly, we propose the concept of gray-level information histogram, the fundamental characteristic of which is that the amplitudes of the components can objectively reflect the contribution of the gray levels and information to the representation of image information. Then, we propose the histogram equalization method that is composed of an automatic histogram separation module and an intensity transformation module, and the histogram separation module is a combination of the proposed prompt multiple threshold procedure and an optimum peak signal-to-noise (PSNR calculation to separate the histogram into small-scale detail, the use of the intensity transformation module can enhance the vein images with vein topological structure and gray information preservation for each generated sub-histogram. Experimental results show that the proposed method can achieve extremely good contrast enhancement effect.

  18. Improvement of temporal and dynamic subtraction images on abdominal CT using 3D global image matching and nonlinear image warping techniques

    International Nuclear Information System (INIS)

    Okumura, E; Sanada, S; Suzuki, M; Takemura, A; Matsui, O

    2007-01-01

    Accurate registration of the corresponding non-enhanced and arterial-phase CT images is necessary to create temporal and dynamic subtraction images for the enhancement of subtle abnormalities. However, respiratory movement causes misregistration at the periphery of the liver. To reduce these misregistration errors, we developed a temporal and dynamic subtraction technique to enhance small HCC by 3D global matching and nonlinear image warping techniques. The study population consisted of 21 patients with HCC. Using the 3D global matching and nonlinear image warping technique, we registered current and previous arterial-phase CT images or current non-enhanced and arterial-phase CT images obtained in the same position. The temporal subtraction image was obtained by subtracting the previous arterial-phase CT image from the warped current arterial-phase CT image. The dynamic subtraction image was obtained by the subtraction of the current non-enhanced CT image from the warped current arterial-phase CT image. The percentage of fair or superior temporal subtraction images increased from 52.4% to 95.2% using the new technique, while on the dynamic subtraction images, the percentage increased from 66.6% to 95.2%. The new subtraction technique may facilitate the diagnosis of subtle HCC based on the superior ability of these subtraction images to show nodular and/or ring enhancement

  19. Methodological development of topographic correction in 2D/3D ToF-SIMS images using AFM images

    Science.gov (United States)

    Jung, Seokwon; Lee, Nodo; Choi, Myungshin; Lee, Jungmin; Cho, Eunkyunng; Joo, Minho

    2018-02-01

    Time-of-flight secondary-ion mass spectrometry (ToF-SIMS) is an emerging technique that provides chemical information directly from the surface of electronic materials, e.g. OLED and solar cell. It is very versatile and highly sensitive mass spectrometric technique that provides surface molecular information with their lateral distribution as a two-dimensional (2D) molecular image. Extending the usefulness of ToF-SIMS, a 3D molecular image can be generated by acquiring multiple 2D images in a stack. These imaging techniques by ToF-SIMS provide an insight into understanding the complex structures of unknown composition in electronic material. However, one drawback in ToF-SIMS is not able to represent topographical information in 2D and 3D mapping images. To overcome this technical limitation, topographic information by ex-situ technique such as atomic force microscopy (AFM) has been combined with chemical information from SIMS that provides both chemical and physical information in one image. The key to combine two different images obtained from ToF-SIMS and AFM techniques is to develop the image processing algorithm, which performs resize and alignment by comparing the specific pixel information of each image. In this work, we present methodological development of the semiautomatic alignment and the 3D structure interpolation system for the combination of 2D/3D images obtained by ToF-SIMS and AFM measurements, which allows providing useful analytical information in a single representation.

  20. Comparison of modern 3D and 2D MR imaging sequences of the wrist at 3 Tesla

    International Nuclear Information System (INIS)

    Rehnitz, C.; Klaan, B.; Amarteifio, E.; Kauczor, H.U.; Weber, M.A.; Stillfried, F. von; Burkholder, I.

    2016-01-01

    To compare the image quality of modern 3 D and 2 D sequences for dedicated wrist imaging at 3 Tesla (T) MRI. At 3 T MRI, 18 patients (mean age: 36.2 years) with wrist pain and 16 healthy volunteers (mean age: 26.4 years) were examined using 2 D proton density-weighted fat-saturated (PDfs), isotropic 3 D TrueFISP, 3 D MEDIC, and 3 D PDfs SPACE sequences. Image quality was rated on a five-point scale (0 - 4) including overall image quality (OIQ), visibility of important structures (cartilage, ligaments, TFCC) and degree of artifacts. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) of cartilage/bone/muscle/fluid as well as the mean overall SNR/CNR were calculated using region-of-interest analysis. ANOVA, paired t-, and Wilcoxon-signed-rank tests were applied. The image quality of all tested sequences was superior to 3 D PDfs SPACE (p < 0.01). 3 D TrueFISP had the highest combined cartilage score (mean: 3.4) and performed better in cartilage comparisons against 3 D PDfs SPACE in both groups and 2 D PDfs in volunteers (p < 0.05). 3 D MEDIC performed better in 7 of 8 comparisons (p < 0.05) regarding ligaments and TFCC. 2 D PDfs provided constantly high scores. The mean overall SNR/CNR for 2 D PDfs, 3 D PDfs SPACE, 3 D TrueFISP, and 3 D MEDIC were 68/65, 32/27, 45/47, and 57/45, respectively. 2 D PDfs performed best in most SNR/CNR comparisons (p < 0.05) and 3 D MEDIC performed best within the 3 D sequences (p < 0.05). Except 3 D PDfs SPACE, all tested 3 D and 2 D sequences provided high image quality. 3 D TrueFISP was best for cartilage imaging, 3 D MEDIC for ligaments and TFCC and 2 D PDfs for general wrist imaging.

  1. Improved detection probability of low level light and infrared image fusion system

    Science.gov (United States)

    Luo, Yuxiang; Fu, Rongguo; Zhang, Junju; Wang, Wencong; Chang, Benkang

    2018-02-01

    Low level light(LLL) image contains rich information on environment details, but is easily affected by the weather. In the case of smoke, rain, cloud or fog, much target information will lose. Infrared image, which is from the radiation produced by the object itself, can be "active" to obtain the target information in the scene. However, the image contrast and resolution is bad, the ability of the acquisition of target details is very poor, and the imaging mode does not conform to the human visual habit. The fusion of LLL and infrared image can make up for the deficiency of each sensor and give play to the advantages of single sensor. At first, we show the hardware design of fusion circuit. Then, through the recognition probability calculation of the target(one person) and the background image(trees), we find that the trees detection probability of LLL image is higher than that of the infrared image, and the person detection probability of the infrared image is obviously higher than that of LLL image. The detection probability of fusion image for one person and trees is higher than that of single detector. Therefore, image fusion can significantly enlarge recognition probability and improve detection efficiency.

  2. Common crus aplasia: diagnosis by 3D volume rendering imaging using 3DFT-CISS sequence

    International Nuclear Information System (INIS)

    Kim, H.J.; Song, J.W.; Chon, K.-M.; Goh, E.-K.

    2004-01-01

    AIM: The purpose of this study was to evaluate the findings of three-dimensional (3D) volume rendering (VR) imaging in common crus aplasia (CCA) of the inner ear. MATERIALS AND METHODS: Using 3D VR imaging of temporal bone constructive interference in steady state (CISS) magnetic resonance (MR) images, we retrospectively reviewed seven inner ears of six children who were candidates for cochlear implants and who had been diagnosed with CCA. As controls, we used the same method to examine 402 inner ears of 201 patients who had no clinical symptoms or signs of sensorineural hearing loss. Temporal bone MR imaging (MRI) was performed with a 1.5 T MR machine using a CISS sequence, and VR of the inner ear was performed on a work station. Morphological image analysis was performed on rotation views of 3D VR images. RESULTS: In all seven cases, CCA was diagnosed by the absence of the common crus. The remaining superior semicircular canal (SCC) was normal in five and hypoplastic in two inner ears, while the posterior SCC was normal in all seven. One patient showed bilateral symmetrical CCA. Complicated combined anomalies were seen in the cochlea, vestibule and lateral SCC. CONCLUSION: 3D VR imaging findings with MR CISS sequence can directly diagnose CCA. This technique may be useful in delineating detailed anomalies of SCCs

  3. The preliminary study of the blood perfusion and ammonia metabolism of pituitary using dynamic 13N-NH3 PET imaging

    International Nuclear Information System (INIS)

    Zhang Xiangsong; Tang Anwu; Qiao Suixian; Chen Liguang; Luo Yaowu; Liu Bin; Xu Weiping

    2002-01-01

    Objective: To preliminarily study the blood perfusion and ammonia metabolism of pituitary using dynamic 13 N-NH 3 PET imaging. Methods: 13 N-NH 3 PET imaging was performed on 21 subjects without pituitary diseases, 6 of them underwent dynamic PET imaging, and 8 of them underwent brain MRI in addition to PET. PET images were registered with MRI. Results: The pituitary could be clearly seen in 13 N-NH 3 PET images, and being confirmed by PET/MRI image fusion. The size of pituitary was (1.07 +- 0.17) cm x (1.09 +- 0.15) cm x (1.14 +- 0.17) cm, the standard uptake value (SUV) was 3.84 +- 1.75, and the radioactivity ratio of pituitary to thalamus was 1.35 +- 0.63. Pituitary image was seen at 10 s after the internal carotid was seen in dynamic 13 N-NH 3 PET imaging. 13 N-NH 3 was retained in pituitary, and was hardly cleaned out within 20 min. The radioactivity ratio of pituitary to internal carotid was 0.75 +- 0.13 when the radioactivity of internal carotid was at its highest level. Conclusions: The blood flow and ammonia metabolism of pituitary can be observed with dynamic 13 N-NH 3 PET imaging. Ammonia is highly extracted by pituitary, and metabolized in pituitary cells

  4. AN IMAGE-BASED TECHNIQUE FOR 3D BUILDING RECONSTRUCTION USING MULTI-VIEW UAV IMAGES

    Directory of Open Access Journals (Sweden)

    F. Alidoost

    2015-12-01

    Full Text Available Nowadays, with the development of the urban areas, the automatic reconstruction of the buildings, as an important objects of the city complex structures, became a challenging topic in computer vision and photogrammetric researches. In this paper, the capability of multi-view Unmanned Aerial Vehicles (UAVs images is examined to provide a 3D model of complex building façades using an efficient image-based modelling workflow. The main steps of this work include: pose estimation, point cloud generation, and 3D modelling. After improving the initial values of interior and exterior parameters at first step, an efficient image matching technique such as Semi Global Matching (SGM is applied on UAV images and a dense point cloud is generated. Then, a mesh model of points is calculated using Delaunay 2.5D triangulation and refined to obtain an accurate model of building. Finally, a texture is assigned to mesh in order to create a realistic 3D model. The resulting model has provided enough details of building based on visual assessment.

  5. 3D dynamic pituitary MR imaging with CAIPIRINHA: Initial experience and comparison with 2D dynamic MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fushimi, Yasutaka, E-mail: yfushimi@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Okada, Tomohisa; Kanagaki, Mitsunori; Yamamoto, Akira; Kanda, Yumiko; Sakamoto, Ryo [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Hojo, Masato; Takahashi, Jun C.; Miyamoto, Susumu [Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Togashi, Kaori [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan)

    2014-10-15

    Objectives: To evaluate the validity of 3D dynamic pituitary MR imaging with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA), with special emphasis on demarcation of pituitary posterior lobe and stalk. Methods: Participants comprised 32 patients who underwent dynamic pituitary MR imaging due to pituitary or parasellar lesions. 3D dynamic MR with CAIPIRINHA was performed at 3 T with 20-s-interval, precontrast, 1st to 5th dynamic images. Normalized values and enhanced ratios (dynamic postcontrast image values divided by precontrast ones) were compared between 3D and 2D dynamic MR imaging for patients with visual identification of posterior lobe and stalk. Results: In 3D, stalk was identified in 29 patients and unidentified in 3, and posterior lobe was identified in 28 and unidentified in 4. In 2D, stalk was identified in 26 patients and unidentified in 6 patients, and posterior lobe was identified in 15 and unidentified in 17. Normalized values of pituitary posterior lobe and stalk were higher in 3D than 2D (P < 0.001). No significant difference in enhancement ratio was seen between 3D and 2D. Conclusions: 3D dynamic pituitary MR provided better identification and higher normalized values of pituitary posterior lobe and stalk than 2D.

  6. Segmentation of the lumen and media-adventitia boundaries of the common carotid artery from 3D ultrasound images

    Science.gov (United States)

    Ukwatta, E.; Awad, J.; Ward, A. D.; Samarabandu, J.; Krasinski, A.; Parraga, G.; Fenster, A.

    2011-03-01

    Three-dimensional ultrasound (3D US) vessel wall volume (VWV) measurements provide high measurement sensitivity and reproducibility for the monitoring and assessment of carotid atherosclerosis. In this paper, we describe a semiautomated approach based on the level set method to delineate the media-adventitia and lumen boundaries of the common carotid artery from 3D US images to support the computation of VWV. Due to the presence of plaque and US image artifacts, the carotid arteries are challenging to segment using image information alone. Our segmentation framework combines several image cues with domain knowledge and limited user interaction. Our method was evaluated with respect to manually outlined boundaries on 430 2D US images extracted from 3D US images of 30 patients who have carotid stenosis of 60% or more. The VWV given by our method differed from that given by manual segmentation by 6.7% +/- 5.0%. For the media-adventitia and lumen segmentations, respectively, our method yielded Dice coefficients of 95.2% +/- 1.6%, 94.3% +/- 2.6%, mean absolute distances of 0.3 +/- 0.1 mm, 0.2 +/- 0.1 mm, maximum absolute distances of 0.8 +/- 0.4 mm, 0.6 +/- 0.3 mm, and volume differences of 4.2% +/- 3.1%, 3.4% +/- 2.6%. The realization of a semi-automated segmentation method will accelerate the translation of 3D carotid US to clinical care for the rapid, non-invasive, and economical monitoring of atherosclerotic disease progression and regression during therapy.

  7. Reconstituted Three-Dimensional Interactive Imaging

    Science.gov (United States)

    Hamilton, Joseph; Foley, Theodore; Duncavage, Thomas; Mayes, Terrence

    2010-01-01

    A method combines two-dimensional images, enhancing the images as well as rendering a 3D, enhanced, interactive computer image or visual model. Any advanced compiler can be used in conjunction with any graphics library package for this method, which is intended to take digitized images and virtually stack them so that they can be interactively viewed as a set of slices. This innovation can take multiple image sources (film or digital) and create a "transparent" image with higher densities in the image being less transparent. The images are then stacked such that an apparent 3D object is created in virtual space for interactive review of the set of images. This innovation can be used with any application where 3D images are taken as slices of a larger object. These could include machines, materials for inspection, geological objects, or human scanning. Illuminous values were stacked into planes with different transparency levels of tissues. These transparency levels can use multiple energy levels, such as density of CT scans or radioactive density. A desktop computer with enough video memory to produce the image is capable of this work. The memory changes with the size and resolution of the desired images to be stacked and viewed.

  8. 3D imaging of nanomaterials by discrete tomography.

    Science.gov (United States)

    Batenburg, K J; Bals, S; Sijbers, J; Kübel, C; Midgley, P A; Hernandez, J C; Kaiser, U; Encina, E R; Coronado, E A; Van Tendeloo, G

    2009-05-01

    The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi(2) nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively.

  9. 3D imaging of nanomaterials by discrete tomography

    International Nuclear Information System (INIS)

    Batenburg, K.J.; Bals, S.; Sijbers, J.; Kuebel, C.; Midgley, P.A.; Hernandez, J.C.; Kaiser, U.; Encina, E.R.; Coronado, E.A.; Van Tendeloo, G.

    2009-01-01

    The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi 2 nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively.

  10. Flatbed-type 3D display systems using integral imaging method

    Science.gov (United States)

    Hirayama, Yuzo; Nagatani, Hiroyuki; Saishu, Tatsuo; Fukushima, Rieko; Taira, Kazuki

    2006-10-01

    We have developed prototypes of flatbed-type autostereoscopic display systems using one-dimensional integral imaging method. The integral imaging system reproduces light beams similar of those produced by a real object. Our display architecture is suitable for flatbed configurations because it has a large margin for viewing distance and angle and has continuous motion parallax. We have applied our technology to 15.4-inch displays. We realized horizontal resolution of 480 with 12 parallaxes due to adoption of mosaic pixel arrangement of the display panel. It allows viewers to see high quality autostereoscopic images. Viewing the display from angle allows the viewer to experience 3-D images that stand out several centimeters from the surface of the display. Mixed reality of virtual 3-D objects and real objects are also realized on a flatbed display. In seeking reproduction of natural 3-D images on the flatbed display, we developed proprietary software. The fast playback of the CG movie contents and real-time interaction are realized with the aid of a graphics card. Realization of the safety 3-D images to the human beings is very important. Therefore, we have measured the effects on the visual function and evaluated the biological effects. For example, the accommodation and convergence were measured at the same time. The various biological effects are also measured before and after the task of watching 3-D images. We have found that our displays show better results than those to a conventional stereoscopic display. The new technology opens up new areas of application for 3-D displays, including arcade games, e-learning, simulations of buildings and landscapes, and even 3-D menus in restaurants.

  11. Open source software for the analysis of corneal deformation parameters on the images from the Corvis tonometer.

    Science.gov (United States)

    Koprowski, Robert

    2015-04-11

    The software supplied with the Corvis tonometer (which is designed to measure intraocular pressure with the use of the air-puff method) is limited to providing basic numerical data. These data relate to the values of the measured intraocular pressure and, for example, applanation amplitudes. However, on the basis of a sequence of images obtained from the Corvis tonometer, it is possible to obtain much more information which is not available in its original software. This will be presented in this paper. The proposed software has been tested on 1400 images from the Corvis tonometer. The number of analysed 2D images (with a resolution of 200 × 576 pixels) in a sequence is arbitrary. However, in typical cases there are 140 images. The proposed software has been written in Matlab (Version 7.11.0.584, R2010b). The methods of image analysis and processing and in particular edge detection and the fast Fourier transform have been applied. The software allows for fully automatic (1) acquisition of 12 new parameters previously unavailable in the original software of the Corvis tonometer. It also enables off-line (2) manual and (3) automatic browsing of images in a sequence; 3D graph visualization of: (4) the corneal deformation and (5) eyeball response; 6) change of the colour palette; (7) filtration and (8) visualization of selected measured values on individual 2D images. In addition, the proposed software enables (9) to save the obtained results for further analysis and processing. The dedicated software described in this paper enables to obtain additional new features of corneal deformations during intraocular pressure measurement. The software can be applied in the diagnosis of corneal deformation vibrations, glaucoma diagnosis, evaluation of measurement repeatability and others. The software has no licensing restrictions and can be used both commercially and non-commercially without any limitations.

  12. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Science.gov (United States)

    Menzel, Claudia; Hayn-Leichsenring, Gregor U; Langner, Oliver; Wiese, Holger; Redies, Christoph

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power). Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1). We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3). Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  13. Multiple-point statistical simulation for hydrogeological models: 3-D training image development and conditioning strategies

    Science.gov (United States)

    Høyer, Anne-Sophie; Vignoli, Giulio; Mejer Hansen, Thomas; Thanh Vu, Le; Keefer, Donald A.; Jørgensen, Flemming

    2017-12-01

    Most studies on the application of geostatistical simulations based on multiple-point statistics (MPS) to hydrogeological modelling focus on relatively fine-scale models and concentrate on the estimation of facies-level structural uncertainty. Much less attention is paid to the use of input data and optimal construction of training images. For instance, even though the training image should capture a set of spatial geological characteristics to guide the simulations, the majority of the research still relies on 2-D or quasi-3-D training images. In the present study, we demonstrate a novel strategy for 3-D MPS modelling characterized by (i) realistic 3-D training images and (ii) an effective workflow for incorporating a diverse group of geological and geophysical data sets. The study covers an area of 2810 km2 in the southern part of Denmark. MPS simulations are performed on a subset of the geological succession (the lower to middle Miocene sediments) which is characterized by relatively uniform structures and dominated by sand and clay. The simulated domain is large and each of the geostatistical realizations contains approximately 45 million voxels with size 100 m × 100 m × 5 m. Data used for the modelling include water well logs, high-resolution seismic data, and a previously published 3-D geological model. We apply a series of different strategies for the simulations based on data quality, and develop a novel method to effectively create observed spatial trends. The training image is constructed as a relatively small 3-D voxel model covering an area of 90 km2. We use an iterative training image development strategy and find that even slight modifications in the training image create significant changes in simulations. Thus, this study shows how to include both the geological environment and the type and quality of input information in order to achieve optimal results from MPS modelling. We present a practical workflow to build the training image and

  14. 3D registration of surfaces for change detection in medical images

    Science.gov (United States)

    Fisher, Elizabeth; van der Stelt, Paul F.; Dunn, Stanley M.

    1997-04-01

    Spatial registration of data sets is essential for quantifying changes that take place over time in cases where the position of a patient with respect to the sensor has been altered. Changes within the region of interest can be problematic for automatic methods of registration. This research addresses the problem of automatic 3D registration of surfaces derived from serial, single-modality images for the purpose of quantifying changes over time. The registration algorithm utilizes motion-invariant, curvature- based geometric properties to derive an approximation to an initial rigid transformation to align two image sets. Following the initial registration, changed portions of the surface are detected and excluded before refining the transformation parameters. The performance of the algorithm was tested using simulation experiments. To quantitatively assess the registration, random noise at various levels, known rigid motion transformations, and analytically-defined volume changes were applied to the initial surface data acquired from models of teeth. These simulation experiments demonstrated that the calculated transformation parameters were accurate to within 1.2 percent of the total applied rotation and 2.9 percent of the total applied translation, even at the highest applied noise levels and simulated wear values.

  15. Aerial 3D display by use of a 3D-shaped screen with aerial imaging by retro-reflection (AIRR)

    Science.gov (United States)

    Kurokawa, Nao; Ito, Shusei; Yamamoto, Hirotsugu

    2017-06-01

    The purpose of this paper is to realize an aerial 3D display. We design optical system that employs a projector below a retro-reflector and a 3D-shaped screen. A floating 3D image is formed with aerial imaging by retro-reflection (AIRR). Our proposed system is composed of a 3D-shaped screen, a projector, a quarter-wave retarder, a retro-reflector, and a reflective polarizer. Because AIRR forms aerial images that are plane-symmetric of the light sources regarding the reflective polarizer, the shape of the 3D screen is inverted from a desired aerial 3D image. In order to expand viewing angle, the 3D-shaped screen is surrounded by a retro-reflector. In order to separate the aerial image from reflected lights on the retro- reflector surface, the retro-reflector is tilted by 30 degrees. A projector is located below the retro-reflector at the same height of the 3D-shaped screen. The optical axis of the projector is orthogonal to the 3D-shaped screen. Scattered light on the 3D-shaped screen forms the aerial 3D image. In order to demonstrate the proposed optical design, a corner-cube-shaped screen is used for the 3D-shaped screen. Thus, the aerial 3D image is a cube that is floating above the reflective polarizer. For example, an aerial green cube is formed by projecting a calculated image on the 3D-shaped screen. The green cube image is digitally inverted in depth by our developed software. Thus, we have succeeded in forming aerial 3D image with our designed optical system.

  16. Segmentation, Reconstruction, and Analysis of Blood Thrombus Formation in 3D 2-Photon Microscopy Images

    Directory of Open Access Journals (Sweden)

    Xu Zhiliang

    2010-01-01

    Full Text Available We study the problem of segmenting, reconstructing, and analyzing the structure growth of thrombi (clots in blood vessels in vivo based on 2-photon microscopic image data. First, we develop an algorithm for segmenting clots in 3D microscopic images based on density-based clustering and methods for dealing with imaging artifacts. Next, we apply the union-of-balls (or alpha-shape algorithm to reconstruct the boundary of clots in 3D. Finally, we perform experimental studies and analysis on the reconstructed clots and obtain quantitative data of thrombus growth and structures. We conduct experiments on laser-induced injuries in vessels of two types of mice (the wild type and the type with low levels of coagulation factor VII and analyze and compare the developing clot structures based on their reconstructed clots from image data. The results we obtain are of biomedical significance. Our quantitative analysis of the clot composition leads to better understanding of the thrombus development, and is valuable to the modeling and verification of computational simulation of thrombogenesis.

  17. The CDF level-3 trigger

    International Nuclear Information System (INIS)

    Devlin, T.

    1993-01-01

    The Collider Detector at Fermilab (CDF) has been operating at the Tevatron and collecting data on proton-antiproton interactions with collision rates above 250,000 Hz. Three levels of filtering select events for data logging at a rate of about 4 Hz. The Level 3 trigger provides most of the capabilities of the offline production programs for event reconstruction and physics analysis. The type of physics triggers, application of cuts, and combinations of logical requirements for event selection are controlled at run time by a trigger table using a syntax fully integrated with the Level 1 and Level 2 hardware triggers. The level 3 software operates in 48 RISC/UNIX processors (over 1000 mips) served by four 20-MByte/sec data buses for input, output and control. The system architecture, debugging, code validation, error reporting, analysis capabilities and performance will be described

  18. Principal component analysis-based imaging angle determination for 3D motion monitoring using single-slice on-board imaging.

    Science.gov (United States)

    Chen, Ting; Zhang, Miao; Jabbour, Salma; Wang, Hesheng; Barbee, David; Das, Indra J; Yue, Ning

    2018-04-10

    Through-plane motion introduces uncertainty in three-dimensional (3D) motion monitoring when using single-slice on-board imaging (OBI) modalities such as cine MRI. We propose a principal component analysis (PCA)-based framework to determine the optimal imaging plane to minimize the through-plane motion for single-slice imaging-based motion monitoring. Four-dimensional computed tomography (4DCT) images of eight thoracic cancer patients were retrospectively analyzed. The target volumes were manually delineated at different respiratory phases of 4DCT. We performed automated image registration to establish the 4D respiratory target motion trajectories for all patients. PCA was conducted using the motion information to define the three principal components of the respiratory motion trajectories. Two imaging planes were determined perpendicular to the second and third principal component, respectively, to avoid imaging with the primary principal component of the through-plane motion. Single-slice images were reconstructed from 4DCT in the PCA-derived orthogonal imaging planes and were compared against the traditional AP/Lateral image pairs on through-plane motion, residual error in motion monitoring, absolute motion amplitude error and the similarity between target segmentations at different phases. We evaluated the significance of the proposed motion monitoring improvement using paired t test analysis. The PCA-determined imaging planes had overall less through-plane motion compared against the AP/Lateral image pairs. For all patients, the average through-plane motion was 3.6 mm (range: 1.6-5.6 mm) for the AP view and 1.7 mm (range: 0.6-2.7 mm) for the Lateral view. With PCA optimization, the average through-plane motion was 2.5 mm (range: 1.3-3.9 mm) and 0.6 mm (range: 0.2-1.5 mm) for the two imaging planes, respectively. The absolute residual error of the reconstructed max-exhale-to-inhale motion averaged 0.7 mm (range: 0.4-1.3 mm, 95% CI: 0.4-1.1 mm) using

  19. Identifying FRBR Work-Level Data in MARC Bibliographic Records for Manifestations of Moving Images

    Directory of Open Access Journals (Sweden)

    Lynne Bisko

    2008-12-01

    Full Text Available The library metadata community is dealing with the challenge of implementing the conceptual model, Functional Requirements for Bibliographic Records (FRBR. In response, the Online Audiovisual Catalogers (OLAC created a task force to study the issues related to creating and using FRBR-based work-level records for moving images. This article presents one part of the task force's work: it looks at the feasibility of creating provisional FRBR work-level records for moving images by extracting data from existing manifestation-level bibliographic records. Using a sample of 941 MARC records, a subgroup of the task force conducted a pilot project to look at five characteristics of moving image works. Here they discuss their methodology; analysis; selected results for two elements, original date (year and director name; and conclude with some suggested changes to MARC coding and current cataloging policy.

  20. Dual functional NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ core-shell nanoparticles for cell temperature sensing and imaging

    Science.gov (United States)

    Shi, Zengliang; Duan, Yue; Zhu, Xingjun; Wang, Qiwei; Li, DongDong; Hu, Ke; Feng, Wei; Li, Fuyou; Xu, Chunxiang

    2018-03-01

    Lanthanide-doped up-conversion nanoparticles (UCNPs) provide a remote temperature sensing approach to monitoring biological microenvironments. In this research, the UCNPs of NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ with hexagonal (β)-phase were synthesized and applied in cell temperature sensing as well as imaging after surface modification with meso-2, 3-dimercaptosuccinic acid. In the core-shell UCNPs, Yb3+ ions were introduced as energy transfer media between sensitizers of Nd3+ and activators of Er3+ to improve Er3+emission and prevent their quenching behavior due to multiple energy levels of Nd3+. Under the excitations of 808 nm and 980 nm lasers, the NaYF4:Yb3+, Er3+@NaYF4:Yb3+, Nd3+ nanoparticles exhibited an efficient green band with two emission peaks at 525 nm and 545 nm, respectively, which originated from the transitions of 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 for Er3+ ions. We demonstrate that an occurrence of good logarithmic linearity exists between the intensity ratio of these two emission peaks and the reciprocal of the inside or outside temperature of NIH-3T3 cells. A better thermal stability is proved through temperature-dependent spectra with a heating-cooling cycle. The obtained viability of NIH-3T3 cells is greater than 90% after incubations of about 12 and 24 (h), and they possess a lower cytotoxicity of UCNPs. This work provides a method for monitoring the cell temperature and its living state from multiple dimensions including temperature response, cell images and visual up-conversion fluorescent color.